diff --git a/ChangeLog b/ChangeLog
index 4fbdb3d..aca6e0f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,15 @@
 mbed TLS ChangeLog (Sorted per branch, date)
 
+= mbed TLS x.x.x branch released xxxx-xx-xx
+
+Features
+   * Add support for restartable ECC operations, enabled by
+     MBEDTLS_ECP_RESTARTABLE (disabled by default) at compile time and
+     mbedtls_ecp_set_max_ops() at runtime, using new xxx_restartable functions
+     in ECP, ECDSA, PK and X509 (CRL not supported yet), and using existing
+     functions in ECDH and SSL (currently only implemented client-side, for
+     ECDHE-ECDSA ciphersuites with TLS 1.2, including client authentication).
+
 = mbed TLS 2.10.0 branch released 2018-06-06
 
 Features
diff --git a/include/mbedtls/config.h b/include/mbedtls/config.h
index ae10a4d..f13b28a 100644
--- a/include/mbedtls/config.h
+++ b/include/mbedtls/config.h
@@ -629,6 +629,23 @@
 #define MBEDTLS_ECP_NIST_OPTIM
 
 /**
+ * \def MBEDTLS_ECP_RESTARTABLE
+ *
+ * Enable "non-blocking" ECC operations that can return early and be resumed.
+ *
+ * This enables \c mbedtls_ecp_set_max_ops() and allows various functions
+ * to return \c MBEDTLS_ERR_ECP_IN_PROGRESS when needed, and then be called
+ * again later with the same arguments in order to further progress and
+ * eventually complete the operation, see \c mbedtls_ecp_set_max_ops().
+ *
+ * This is useful in non-threaded environments if you want to avoid blocking
+ * for too long on ECC (hence, X509 or SSL/TLS) operations.
+ *
+ * Uncomment this macro to enable restartable ECC computations.
+ */
+//#define MBEDTLS_ECP_RESTARTABLE
+
+/**
  * \def MBEDTLS_ECDSA_DETERMINISTIC
  *
  * Enable deterministic ECDSA (RFC 6979).
diff --git a/include/mbedtls/ecdh.h b/include/mbedtls/ecdh.h
index 5fdf55a..f6e6702 100644
--- a/include/mbedtls/ecdh.h
+++ b/include/mbedtls/ecdh.h
@@ -50,6 +50,10 @@
 } mbedtls_ecdh_side;
 
 /**
+ *
+ * \warning         Performing multiple operations concurrently on the same
+ *                  ECDSA context is not supported; objects of this type
+ *                  should not be shared between multiple threads.
  * \brief           The ECDH context structure.
  */
 typedef struct
@@ -63,6 +67,10 @@
     mbedtls_ecp_point Vi;    /*!< The blinding value. */
     mbedtls_ecp_point Vf;    /*!< The unblinding value. */
     mbedtls_mpi _d;          /*!< The previous \p d. */
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    int restart_enabled;        /*!< The flag for restartable mode. */
+    mbedtls_ecp_restart_ctx rs; /*!< The restart context for EC computations. */
+#endif
 }
 mbedtls_ecdh_context;
 
@@ -85,7 +93,8 @@
  * \return          \c 0 on success.
  * \return          An \c MBEDTLS_ERR_ECP_XXX or
  *                  \c MBEDTLS_MPI_XXX error code on failure.
- *
+ * \return          #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of
+ *                  operations was reached: see \c mbedtls_ecp_set_max_ops().
  */
 int mbedtls_ecdh_gen_public( mbedtls_ecp_group *grp, mbedtls_mpi *d, mbedtls_ecp_point *Q,
                      int (*f_rng)(void *, unsigned char *, size_t),
@@ -114,6 +123,8 @@
  * \return          \c 0 on success.
  * \return          An \c MBEDTLS_ERR_ECP_XXX or
  *                  \c MBEDTLS_MPI_XXX error code on failure.
+ * \return          #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of
+ *                  operations was reached: see \c mbedtls_ecp_set_max_ops().
  */
 int mbedtls_ecdh_compute_shared( mbedtls_ecp_group *grp, mbedtls_mpi *z,
                          const mbedtls_ecp_point *Q, const mbedtls_mpi *d,
@@ -156,6 +167,8 @@
  *
  * \return          \c 0 on success.
  * \return          An \c MBEDTLS_ERR_ECP_XXX error code on failure.
+ * \return          #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of
+ *                  operations was reached: see \c mbedtls_ecp_set_max_ops().
  */
 int mbedtls_ecdh_make_params( mbedtls_ecdh_context *ctx, size_t *olen,
                       unsigned char *buf, size_t blen,
@@ -198,6 +211,8 @@
  *
  * \return          \c 0 on success.
  * \return          An \c MBEDTLS_ERR_ECP_XXX error code on failure.
+ * \return          #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of
+ *                  operations was reached: see \c mbedtls_ecp_set_max_ops().
  *
  */
 int mbedtls_ecdh_get_params( mbedtls_ecdh_context *ctx, const mbedtls_ecp_keypair *key,
@@ -221,6 +236,8 @@
  *
  * \return          \c 0 on success.
  * \return          An \c MBEDTLS_ERR_ECP_XXX error code on failure.
+ * \return          #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of
+ *                  operations was reached: see \c mbedtls_ecp_set_max_ops().
  */
 int mbedtls_ecdh_make_public( mbedtls_ecdh_context *ctx, size_t *olen,
                       unsigned char *buf, size_t blen,
@@ -267,12 +284,30 @@
  *
  * \return          \c 0 on success.
  * \return          An \c MBEDTLS_ERR_ECP_XXX error code on failure.
+ * \return          #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of
+ *                  operations was reached: see \c mbedtls_ecp_set_max_ops().
  */
 int mbedtls_ecdh_calc_secret( mbedtls_ecdh_context *ctx, size_t *olen,
                       unsigned char *buf, size_t blen,
                       int (*f_rng)(void *, unsigned char *, size_t),
                       void *p_rng );
 
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+/**
+ * \brief           This function enables restartable EC computations for this
+ *                  context.  (Default: disabled.)
+ *
+ * \see             \c mbedtls_ecp_set_max_ops()
+ *
+ * \note            It is not possible to safely disable restartable
+ *                  computations once enabled, except by free-ing the context,
+ *                  which cancels possible in-progress operations.
+ *
+ * \param ctx       The ECDH context.
+ */
+void mbedtls_ecdh_enable_restart( mbedtls_ecdh_context *ctx );
+#endif /* MBEDTLS_ECP_RESTARTABLE */
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/include/mbedtls/ecdsa.h b/include/mbedtls/ecdsa.h
index ce1a03d..710fdb9 100644
--- a/include/mbedtls/ecdsa.h
+++ b/include/mbedtls/ecdsa.h
@@ -55,16 +55,65 @@
 /** The maximal size of an ECDSA signature in Bytes. */
 #define MBEDTLS_ECDSA_MAX_LEN  ( 3 + 2 * ( 3 + MBEDTLS_ECP_MAX_BYTES ) )
 
-/**
- * \brief           The ECDSA context structure.
- */
-typedef mbedtls_ecp_keypair mbedtls_ecdsa_context;
-
 #ifdef __cplusplus
 extern "C" {
 #endif
 
 /**
+ * \brief           The ECDSA context structure.
+ *
+ * \warning         Performing multiple operations concurrently on the same
+ *                  ECDSA context is not supported; objects of this type
+ *                  should not be shared between multiple threads.
+ */
+typedef mbedtls_ecp_keypair mbedtls_ecdsa_context;
+
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+
+/**
+ * \brief           Internal restart context for ecdsa_verify()
+ *
+ * \note            Opaque struct
+ */
+typedef struct mbedtls_ecdsa_restart_ver mbedtls_ecdsa_restart_ver_ctx;
+
+/**
+ * \brief           Internal restart context for ecdsa_sign()
+ *
+ * \note            Opaque struct, defined in ecdsa.c
+ */
+typedef struct mbedtls_ecdsa_restart_sig mbedtls_ecdsa_restart_sig_ctx;
+
+#if defined(MBEDTLS_ECDSA_DETERMINISTIC)
+/**
+ * \brief           Internal restart context for ecdsa_sign_det()
+ *
+ * \note            Opaque struct, defined in ecdsa.c
+ */
+typedef struct mbedtls_ecdsa_restart_det mbedtls_ecdsa_restart_det_ctx;
+#endif
+
+/**
+ * \brief           General context for resuming ECDSA operations
+ */
+typedef struct
+{
+    mbedtls_ecp_restart_ctx ecp;        /*!<  base context (admin+ecp info) */
+    mbedtls_ecdsa_restart_ver_ctx *ver; /*!<  ecdsa_verify() sub-context    */
+    mbedtls_ecdsa_restart_sig_ctx *sig; /*!<  ecdsa_sign() sub-context      */
+#if defined(MBEDTLS_ECDSA_DETERMINISTIC)
+    mbedtls_ecdsa_restart_det_ctx *det; /*!<  ecdsa_sign_det() sub-context  */
+#endif
+} mbedtls_ecdsa_restart_ctx;
+
+#else /* MBEDTLS_ECP_RESTARTABLE */
+
+/* Now we can declare functions that take a pointer to that */
+typedef void mbedtls_ecdsa_restart_ctx;
+
+#endif /* MBEDTLS_ECP_RESTARTABLE */
+
+/**
  * \brief           This function computes the ECDSA signature of a
  *                  previously-hashed message.
  *
@@ -205,6 +254,40 @@
                            int (*f_rng)(void *, unsigned char *, size_t),
                            void *p_rng );
 
+/**
+ * \brief           This function computes the ECDSA signature and writes it
+ *                  to a buffer, in a restartable way.
+ *
+ * \see             \c mbedtls_ecdsa_write_signature()
+ *
+ * \note            This function is like \c mbedtls_ecdsa_write_signature()
+ *                  but it can return early and restart according to the limit
+ *                  set with \c mbedtls_ecp_set_max_ops() to reduce blocking.
+ *
+ * \param ctx       The ECDSA context.
+ * \param md_alg    The message digest that was used to hash the message.
+ * \param hash      The message hash.
+ * \param hlen      The length of the hash.
+ * \param sig       The buffer that holds the signature.
+ * \param slen      The length of the signature written.
+ * \param f_rng     The RNG function.
+ * \param p_rng     The RNG context.
+ * \param rs_ctx    The restart context.
+ *
+ * \return          \c 0 on success.
+ * \return          An \c MBEDTLS_ERR_ECP_XXX, \c MBEDTLS_ERR_MPI_XXX or
+ *                  \c MBEDTLS_ERR_ASN1_XXX error code on failure.
+ * \return          #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of
+ *                  operations was reached: see \c mbedtls_ecp_set_max_ops().
+ */
+int mbedtls_ecdsa_write_signature_restartable( mbedtls_ecdsa_context *ctx,
+                           mbedtls_md_type_t md_alg,
+                           const unsigned char *hash, size_t hlen,
+                           unsigned char *sig, size_t *slen,
+                           int (*f_rng)(void *, unsigned char *, size_t),
+                           void *p_rng,
+                           mbedtls_ecdsa_restart_ctx *rs_ctx );
+
 #if defined(MBEDTLS_ECDSA_DETERMINISTIC)
 #if ! defined(MBEDTLS_DEPRECATED_REMOVED)
 #if defined(MBEDTLS_DEPRECATED_WARNING)
@@ -289,6 +372,37 @@
                           const unsigned char *sig, size_t slen );
 
 /**
+ * \brief           This function reads and verifies an ECDSA signature,
+ *                  in a restartable way.
+ *
+ * \see             \c mbedtls_ecdsa_read_signature()
+ *
+ * \note            This function is like \c mbedtls_ecdsa_read_signature()
+ *                  but it can return early and restart according to the limit
+ *                  set with \c mbedtls_ecp_set_max_ops() to reduce blocking.
+ *
+ * \param ctx       The ECDSA context.
+ * \param hash      The message hash.
+ * \param hlen      The size of the hash.
+ * \param sig       The signature to read and verify.
+ * \param slen      The size of \p sig.
+ * \param rs_ctx    The restart context
+ *
+ * \return          \c 0 on success.
+ * \return          #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if signature is invalid.
+ * \return          #MBEDTLS_ERR_ECP_SIG_LEN_MISMATCH if there is a valid
+ *                  signature in \p sig, but its length is less than \p siglen.
+ * \return          An \c MBEDTLS_ERR_ECP_XXX or \c MBEDTLS_ERR_MPI_XXX
+ *                  error code on failure for any other reason.
+ * \return          #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of
+ *                  operations was reached: see \c mbedtls_ecp_set_max_ops().
+ */
+int mbedtls_ecdsa_read_signature_restartable( mbedtls_ecdsa_context *ctx,
+                          const unsigned char *hash, size_t hlen,
+                          const unsigned char *sig, size_t slen,
+                          mbedtls_ecdsa_restart_ctx *rs_ctx );
+
+/**
  * \brief          This function generates an ECDSA keypair on the given curve.
  *
  * \see            ecp.h
@@ -332,6 +446,18 @@
  */
 void mbedtls_ecdsa_free( mbedtls_ecdsa_context *ctx );
 
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+/**
+ * \brief           Initialize a restart context
+ */
+void mbedtls_ecdsa_restart_init( mbedtls_ecdsa_restart_ctx *ctx );
+
+/**
+ * \brief           Free the components of a restart context
+ */
+void mbedtls_ecdsa_restart_free( mbedtls_ecdsa_restart_ctx *ctx );
+#endif /* MBEDTLS_ECP_RESTARTABLE */
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/include/mbedtls/ecp.h b/include/mbedtls/ecp.h
index 3a40798..465d750 100644
--- a/include/mbedtls/ecp.h
+++ b/include/mbedtls/ecp.h
@@ -50,6 +50,7 @@
 #define MBEDTLS_ERR_ECP_INVALID_KEY                       -0x4C80  /**< Invalid private or public key. */
 #define MBEDTLS_ERR_ECP_SIG_LEN_MISMATCH                  -0x4C00  /**< The buffer contains a valid signature followed by more data. */
 #define MBEDTLS_ERR_ECP_HW_ACCEL_FAILED                   -0x4B80  /**< The ECP hardware accelerator failed. */
+#define MBEDTLS_ERR_ECP_IN_PROGRESS                       -0x4B00  /**< Operation in progress, try again with the same parameters. */
 
 #ifdef __cplusplus
 extern "C" {
@@ -181,6 +182,68 @@
 }
 mbedtls_ecp_group;
 
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+
+/**
+ * \brief           Internal restart context for multiplication
+ *
+ * \note            Opaque struct
+ */
+typedef struct mbedtls_ecp_restart_mul mbedtls_ecp_restart_mul_ctx;
+
+/**
+ * \brief           Internal restart context for ecp_muladd()
+ *
+ * \note            Opaque struct
+ */
+typedef struct mbedtls_ecp_restart_muladd mbedtls_ecp_restart_muladd_ctx;
+
+/**
+ * \brief           General context for resuming ECC operations
+ */
+typedef struct
+{
+    unsigned ops_done;                  /*!<  current ops count             */
+    unsigned depth;                     /*!<  call depth (0 = top-level)    */
+    mbedtls_ecp_restart_mul_ctx *rsm;   /*!<  ecp_mul_comb() sub-context    */
+    mbedtls_ecp_restart_muladd_ctx *ma; /*!<  ecp_muladd() sub-context      */
+} mbedtls_ecp_restart_ctx;
+
+/*
+ * Operation counts for restartable functions
+ */
+#define MBEDTLS_ECP_OPS_CHK   3 /*!< basic ops count for ecp_check_pubkey()  */
+#define MBEDTLS_ECP_OPS_DBL   8 /*!< basic ops count for ecp_double_jac()    */
+#define MBEDTLS_ECP_OPS_ADD  11 /*!< basic ops count for see ecp_add_mixed() */
+#define MBEDTLS_ECP_OPS_INV 120 /*!< empirical equivalent for mpi_mod_inv()  */
+
+/**
+ * \brief           Internal; for restartable functions in other modules.
+ *                  Check and update basic ops budget.
+ *
+ * \param grp       Group structure
+ * \param rs_ctx    Restart context
+ * \param ops       Number of basic ops to do
+ *
+ * \return          0 is doing 'ops' basic ops is still allowed,
+ *                  MBEDTLS_ERR_ECP_IN_PROGRESS otherwise.
+ */
+int mbedtls_ecp_check_budget( const mbedtls_ecp_group *grp,
+                              mbedtls_ecp_restart_ctx *rs_ctx,
+                              unsigned ops );
+
+/* Utility macro for checking and updating ops budget */
+#define MBEDTLS_ECP_BUDGET( ops )   MBEDTLS_MPI_CHK( mbedtls_ecp_check_budget( grp, rs_ctx, ops ) );
+
+#else /* MBEDTLS_ECP_RESTARTABLE */
+
+#define MBEDTLS_ECP_BUDGET( ops )   /* no-op; for compatibility */
+
+/* We want to declare restartable versions of existing functions anyway */
+typedef void mbedtls_ecp_restart_ctx;
+
+#endif /* MBEDTLS_ECP_RESTARTABLE */
+
 /**
  * \name SECTION: Module settings
  *
@@ -270,6 +333,65 @@
  */
 #define MBEDTLS_ECP_TLS_NAMED_CURVE    3   /**< The named_curve of ECCurveType. */
 
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+/**
+ * \brief           Set the maximum number of basic operations done in a row.
+ *
+ *                  If more operations are needed to complete a computation,
+ *                  MBEDTLS_ERR_ECP_IN_PROGRESS will be returned by the
+ *                  function performing the computation. It is then the
+ *                  caller's responsibility to either call again with the same
+ *                  parameters until it returns 0 or an error code; or to free
+ *                  the restart context if the operation is to be aborted.
+ *
+ *                  It is strictly required that all input parameters and the
+ *                  restart context be the same on successive calls for the
+ *                  same operation, but output parameters need not be the
+ *                  same; they must not be used until the function finally
+ *                  returns 0.
+ *
+ *                  This only affects functions that accept a pointer to a
+ *                  \c mbedtls_ecp_restart_ctx as an argument, and only works
+ *                  if that pointer valid (in particular, not NULL).
+ *
+ * \param max_ops   Maximum number of basic operations done in a row.
+ *                  Default: 0 (unlimited).
+ *                  Lower (non-zero) values mean ECC functions will block for
+ *                  a lesser maximum amount of time.
+ *
+ * \note            A "basic operation" is defined as a rough equivalent of a
+ *                  multiplication in GF(p) for the NIST P-256 curve.
+ *                  As an indication, with default settings, a scalar
+ *                  multiplication (full run of \c mbedtls_ecp_mul()) is:
+ *                  - about 3300 basic operations for P-256
+ *                  - about 9400 basic operations for P-384
+ *
+ * \note            Very low values are not always respected: sometimes
+ *                  functions need to block for a minimum number of
+ *                  operations, and will do so even if max_ops is set to a
+ *                  lower value.  That minimum depends on the curve size, and
+ *                  can be made lower by decreasing the value of
+ *                  \c MBEDTLS_ECP_WINDOW_SIZE.  As an indication, here is the
+ *                  lowest effective value for various curves and values of
+ *                  that parameter (w for short):
+ *                          w=6     w=5     w=4     w=3     w=2
+ *                  P-256   208     208     160     136     124
+ *                  P-384   682     416     320     272     248
+ *                  P-521  1364     832     640     544     496
+ *
+ * \note            This setting is currently ignored by Curve25519
+ */
+void mbedtls_ecp_set_max_ops( unsigned max_ops );
+
+/**
+ * \brief           Check if restart is enabled (max_ops != 0)
+ *
+ * \return          0 if max_ops == 0 (restart disabled)
+ *                  1 otherwise (restart enabled)
+ */
+int mbedtls_ecp_restart_enabled( void );
+#endif /* MBEDTLS_ECP_RESTARTABLE */
+
 /**
  * \brief           This function retrieves the information defined in
  *                  mbedtls_ecp_curve_info() for all supported curves in order
@@ -366,6 +488,18 @@
  */
 void mbedtls_ecp_keypair_free( mbedtls_ecp_keypair *key );
 
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+/**
+ * \brief           Initialize a restart context
+ */
+void mbedtls_ecp_restart_init( mbedtls_ecp_restart_ctx *ctx );
+
+/**
+ * \brief           Free the components of a restart context
+ */
+void mbedtls_ecp_restart_free( mbedtls_ecp_restart_ctx *ctx );
+#endif /* MBEDTLS_ECP_RESTARTABLE */
+
 /**
  * \brief           This function copies the contents of point \p Q into
  *                  point \p P.
@@ -598,6 +732,33 @@
              int (*f_rng)(void *, unsigned char *, size_t), void *p_rng );
 
 /**
+ * \brief           This function performs multiplication of a point by
+ *                  an integer: \p R = \p m * \p P in a restartable way.
+ *
+ *                  \c mbedtls_ecp_mul()
+ *
+ * \note            This function does the same as \c mbedtls_ecp_mul(), but
+ *                  it can return early and restart according to the limit set
+ *                  with \c mbedtls_ecp_set_max_ops() to reduce blocking.
+ *
+ * \param grp       The ECP group.
+ * \param R         The destination point.
+ * \param m         The integer by which to multiply.
+ * \param P         The point to multiply.
+ * \param f_rng     The RNG function.
+ * \param p_rng     The RNG context.
+ * \param rs_ctx    The restart context.
+ *
+ * \return          See \c mbedtls_ecp_mul(), or
+ *                  MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of
+ *                  operations was reached: see \c mbedtls_ecp_set_max_ops().
+ */
+int mbedtls_ecp_mul_restartable( mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
+             const mbedtls_mpi *m, const mbedtls_ecp_point *P,
+             int (*f_rng)(void *, unsigned char *, size_t), void *p_rng,
+             mbedtls_ecp_restart_ctx *rs_ctx );
+
+/**
  * \brief           This function performs multiplication and addition of two
  *                  points by integers: \p R = \p m * \p P + \p n * \p Q
  *
@@ -624,6 +785,39 @@
              const mbedtls_mpi *n, const mbedtls_ecp_point *Q );
 
 /**
+ * \brief           This function performs multiplication and addition of two
+ *                  points by integers: \p R = \p m * \p P + \p n * \p Q in a
+ *                  reastartable way.
+ *
+ * \see             \c mbedtls_ecp_muladd()
+ *
+ * \note            This function works the same as \c mbedtls_ecp_muladd(),
+ *                  but it can return early and restart according to the limit
+ *                  set with \c mbedtls_ecp_set_max_ops() to reduce blocking.
+ *
+ * \param grp       The ECP group.
+ * \param R         The destination point.
+ * \param m         The integer by which to multiply \p P.
+ * \param P         The point to multiply by \p m.
+ * \param n         The integer by which to multiply \p Q.
+ * \param Q         The point to be multiplied by \p n.
+ * \param rs_ctx    The restart context.
+ *
+ * \return          \c 0 on success.
+ * \return          #MBEDTLS_ERR_ECP_INVALID_KEY if \p m or \p n are not
+ *                  valid private keys, or \p P or \p Q are not valid public
+ *                  keys.
+ * \return          #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure.
+ * \return          #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of
+ *                  operations was reached: see \c mbedtls_ecp_set_max_ops().
+ */
+int mbedtls_ecp_muladd_restartable(
+             mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
+             const mbedtls_mpi *m, const mbedtls_ecp_point *P,
+             const mbedtls_mpi *n, const mbedtls_ecp_point *Q,
+             mbedtls_ecp_restart_ctx *rs_ctx );
+
+/**
  * \brief           This function checks that a point is a valid public key
  *                  on this curve.
  *
@@ -666,6 +860,23 @@
 int mbedtls_ecp_check_privkey( const mbedtls_ecp_group *grp, const mbedtls_mpi *d );
 
 /**
+ * \brief           This function generates a private key.
+ *
+ * \param grp       The ECP group.
+ * \param d         The Destination MPI (secret part).
+ * \param f_rng     The RNG function.
+ * \param p_rng     The RNG parameter.
+ *
+ * \return          \c 0 on success.
+ * \return          An \c MBEDTLS_ERR_ECP_XXX or \c MBEDTLS_MPI_XXX error code
+ *                  on failure.
+ */
+int mbedtls_ecp_gen_privkey( const mbedtls_ecp_group *grp,
+                     mbedtls_mpi *d,
+                     int (*f_rng)(void *, unsigned char *, size_t),
+                     void *p_rng );
+
+/**
  * \brief           This function generates a keypair with a configurable base
  *                  point.
  *
diff --git a/include/mbedtls/error.h b/include/mbedtls/error.h
index a17f8d8..22895e1 100644
--- a/include/mbedtls/error.h
+++ b/include/mbedtls/error.h
@@ -87,7 +87,7 @@
  * DHM       3   11
  * PK        3   15 (Started from top)
  * RSA       4   11
- * ECP       4   9 (Started from top)
+ * ECP       4   10 (Started from top)
  * MD        5   5
  * CIPHER    6   8
  * SSL       6   17 (Started from top)
diff --git a/include/mbedtls/pk.h b/include/mbedtls/pk.h
index ee06b2f..d597393 100644
--- a/include/mbedtls/pk.h
+++ b/include/mbedtls/pk.h
@@ -131,6 +131,20 @@
     void *                      pk_ctx;  /**< Underlying public key context  */
 } mbedtls_pk_context;
 
+#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
+/**
+ * \brief           Context for resuming operations
+ */
+typedef struct
+{
+    const mbedtls_pk_info_t *   pk_info; /**< Public key informations        */
+    void *                      rs_ctx;  /**< Underlying restart context     */
+} mbedtls_pk_restart_ctx;
+#else /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
+/* Now we can declare functions that take a pointer to that */
+typedef void mbedtls_pk_restart_ctx;
+#endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
+
 #if defined(MBEDTLS_RSA_C)
 /**
  * Quick access to an RSA context inside a PK context.
@@ -190,6 +204,18 @@
  */
 void mbedtls_pk_free( mbedtls_pk_context *ctx );
 
+#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
+/**
+ * \brief           Initialize a restart context
+ */
+void mbedtls_pk_restart_init( mbedtls_pk_restart_ctx *ctx );
+
+/**
+ * \brief           Free the components of a restart context
+ */
+void mbedtls_pk_restart_free( mbedtls_pk_restart_ctx *ctx );
+#endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
+
 /**
  * \brief           Initialize a PK context with the information given
  *                  and allocates the type-specific PK subcontext.
@@ -287,6 +313,32 @@
                const unsigned char *sig, size_t sig_len );
 
 /**
+ * \brief           Restartable version of \c mbedtls_pk_verify()
+ *
+ * \note            Performs the same job as \c mbedtls_pk_verify(), but can
+ *                  return early and restart according to the limit set with
+ *                  \c mbedtls_ecp_set_max_ops() to reduce blocking for ECC
+ *                  operations. For RSA, same as \c mbedtls_pk_verify().
+ *
+ * \param ctx       PK context to use
+ * \param md_alg    Hash algorithm used (see notes)
+ * \param hash      Hash of the message to sign
+ * \param hash_len  Hash length or 0 (see notes)
+ * \param sig       Signature to verify
+ * \param sig_len   Signature length
+ * \param rs_ctx    Restart context (NULL to disable restart)
+ *
+ * \return          See \c mbedtls_pk_verify(), or
+ *                  MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of
+ *                  operations was reached: see \c mbedtls_ecp_set_max_ops().
+ */
+int mbedtls_pk_verify_restartable( mbedtls_pk_context *ctx,
+               mbedtls_md_type_t md_alg,
+               const unsigned char *hash, size_t hash_len,
+               const unsigned char *sig, size_t sig_len,
+               mbedtls_pk_restart_ctx *rs_ctx );
+
+/**
  * \brief           Verify signature, with options.
  *                  (Includes verification of the padding depending on type.)
  *
@@ -350,6 +402,35 @@
              int (*f_rng)(void *, unsigned char *, size_t), void *p_rng );
 
 /**
+ * \brief           Restartable version of \c mbedtls_pk_sign()
+ *
+ * \note            Performs the same job as \c mbedtls_pk_sign(), but can
+ *                  return early and restart according to the limit set with
+ *                  \c mbedtls_ecp_set_max_ops() to reduce blocking for ECC
+ *                  operations. For RSA, same as \c mbedtls_pk_sign().
+ *
+ * \param ctx       PK context to use - must hold a private key
+ * \param md_alg    Hash algorithm used (see notes)
+ * \param hash      Hash of the message to sign
+ * \param hash_len  Hash length or 0 (see notes)
+ * \param sig       Place to write the signature
+ * \param sig_len   Number of bytes written
+ * \param f_rng     RNG function
+ * \param p_rng     RNG parameter
+ * \param rs_ctx    Restart context (NULL to disable restart)
+ *
+ * \return          See \c mbedtls_pk_sign(), or
+ *                  MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of
+ *                  operations was reached: see \c mbedtls_ecp_set_max_ops().
+ */
+int mbedtls_pk_sign_restartable( mbedtls_pk_context *ctx,
+             mbedtls_md_type_t md_alg,
+             const unsigned char *hash, size_t hash_len,
+             unsigned char *sig, size_t *sig_len,
+             int (*f_rng)(void *, unsigned char *, size_t), void *p_rng,
+             mbedtls_pk_restart_ctx *rs_ctx );
+
+/**
  * \brief           Decrypt message (including padding if relevant).
  *
  * \param ctx       PK context to use - must hold a private key
diff --git a/include/mbedtls/pk_internal.h b/include/mbedtls/pk_internal.h
index 3dae0fc..48b7a5f 100644
--- a/include/mbedtls/pk_internal.h
+++ b/include/mbedtls/pk_internal.h
@@ -59,6 +59,21 @@
                       int (*f_rng)(void *, unsigned char *, size_t),
                       void *p_rng );
 
+#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
+    /** Verify signature (restartable) */
+    int (*verify_rs_func)( void *ctx, mbedtls_md_type_t md_alg,
+                           const unsigned char *hash, size_t hash_len,
+                           const unsigned char *sig, size_t sig_len,
+                           void *rs_ctx );
+
+    /** Make signature (restartable) */
+    int (*sign_rs_func)( void *ctx, mbedtls_md_type_t md_alg,
+                         const unsigned char *hash, size_t hash_len,
+                         unsigned char *sig, size_t *sig_len,
+                         int (*f_rng)(void *, unsigned char *, size_t),
+                         void *p_rng, void *rs_ctx );
+#endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
+
     /** Decrypt message */
     int (*decrypt_func)( void *ctx, const unsigned char *input, size_t ilen,
                          unsigned char *output, size_t *olen, size_t osize,
@@ -80,6 +95,14 @@
     /** Free the given context */
     void (*ctx_free_func)( void *ctx );
 
+#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
+    /** Allocate the restart context */
+    void * (*rs_alloc_func)( void );
+
+    /** Free the restart context */
+    void (*rs_free_func)( void *rs_ctx );
+#endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
+
     /** Interface with the debug module */
     void (*debug_func)( const void *ctx, mbedtls_pk_debug_item *items );
 
diff --git a/include/mbedtls/ssl_internal.h b/include/mbedtls/ssl_internal.h
index 60b431a..6f8bebe 100644
--- a/include/mbedtls/ssl_internal.h
+++ b/include/mbedtls/ssl_internal.h
@@ -93,6 +93,14 @@
 #endif /* MBEDTLS_SSL_PROTO_TLS1_1 */
 #endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
 
+/* Shorthand for restartable ECC */
+#if defined(MBEDTLS_ECP_RESTARTABLE) && \
+    defined(MBEDTLS_SSL_CLI_C) && \
+    defined(MBEDTLS_SSL_PROTO_TLS1_2) && \
+    defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED)
+#define MBEDTLS_SSL__ECP_RESTARTABLE
+#endif
+
 #define MBEDTLS_SSL_INITIAL_HANDSHAKE           0
 #define MBEDTLS_SSL_RENEGOTIATION_IN_PROGRESS   1   /* In progress */
 #define MBEDTLS_SSL_RENEGOTIATION_DONE          2   /* Done or aborted */
@@ -243,6 +251,18 @@
     mbedtls_x509_crl *sni_ca_crl;       /*!< trusted CAs CRLs from SNI      */
 #endif /* MBEDTLS_SSL_SERVER_NAME_INDICATION */
 #endif /* MBEDTLS_X509_CRT_PARSE_C */
+#if defined(MBEDTLS_SSL__ECP_RESTARTABLE)
+    int ecrs_enabled;                   /*!< Handshake supports EC restart? */
+    mbedtls_x509_crt_restart_ctx ecrs_ctx;  /*!< restart context            */
+    enum { /* this complements ssl->state with info on intra-state operations */
+        ssl_ecrs_none = 0,              /*!< nothing going on (yet)         */
+        ssl_ecrs_crt_verify,            /*!< Certificate: crt_verify()      */
+        ssl_ecrs_ske_start_processing,  /*!< ServerKeyExchange: step 1      */
+        ssl_ecrs_ske_ecdh_calc_secret,  /*!< ServerKeyExchange: ECDH step 2 */
+        ssl_ecrs_crt_vrfy_sign,         /*!< CertificateVerify: pk_sign()   */
+    } ecrs_state;                       /*!< current (or last) operation    */
+    size_t ecrs_n;                      /*!< place for saving a length      */
+#endif
 #if defined(MBEDTLS_SSL_PROTO_DTLS)
     unsigned int out_msg_seq;           /*!<  Outgoing handshake sequence number */
     unsigned int in_msg_seq;            /*!<  Incoming handshake sequence number */
diff --git a/include/mbedtls/x509_crt.h b/include/mbedtls/x509_crt.h
index ac23cff..1c3007d 100644
--- a/include/mbedtls/x509_crt.h
+++ b/include/mbedtls/x509_crt.h
@@ -143,6 +143,63 @@
 }
 mbedtls_x509write_cert;
 
+/**
+ * Item in a verification chain: cert and flags for it
+ */
+typedef struct {
+    mbedtls_x509_crt *crt;
+    uint32_t flags;
+} mbedtls_x509_crt_verify_chain_item;
+
+/**
+ * Max size of verification chain: end-entity + intermediates + trusted root
+ */
+#define MBEDTLS_X509_MAX_VERIFY_CHAIN_SIZE  ( MBEDTLS_X509_MAX_INTERMEDIATE_CA + 2 )
+
+/**
+ * Verification chain as built by \c mbedtls_crt_verify_chain()
+ */
+typedef struct
+{
+    mbedtls_x509_crt_verify_chain_item items[MBEDTLS_X509_MAX_VERIFY_CHAIN_SIZE];
+    unsigned len;
+} mbedtls_x509_crt_verify_chain;
+
+#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
+
+/**
+ * \brief       Context for resuming X.509 verify operations
+ */
+typedef struct
+{
+    /* for check_signature() */
+    mbedtls_pk_restart_ctx pk;
+
+    /* for find_parent_in() */
+    mbedtls_x509_crt *parent; /* non-null iff parent_in in progress */
+    mbedtls_x509_crt *fallback_parent;
+    int fallback_sign_good;
+
+    /* for find_parent() */
+    int parent_is_trusted; /* -1 if find_parent is not in progress */
+
+    /* for verify_chain() */
+    enum {
+        x509_crt_rs_none,
+        x509_crt_rs_find_parent,
+    } in_progress;  /* none if no operation is in progress */
+    int self_cnt;
+    mbedtls_x509_crt_verify_chain ver_chain;
+
+} mbedtls_x509_crt_restart_ctx;
+
+#else /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
+
+/* Now we can declare functions that take a pointer to that */
+typedef void mbedtls_x509_crt_restart_ctx;
+
+#endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
+
 #if defined(MBEDTLS_X509_CRT_PARSE_C)
 /**
  * Default security profile. Should provide a good balance between security
@@ -353,6 +410,37 @@
                      int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
                      void *p_vrfy );
 
+/**
+ * \brief          Restartable version of \c mbedtls_crt_verify_with_profile()
+ *
+ * \note           Performs the same job as \c mbedtls_crt_verify_with_profile()
+ *                 but can return early and restart according to the limit
+ *                 set with \c mbedtls_ecp_set_max_ops() to reduce blocking.
+ *
+ * \param crt      a certificate (chain) to be verified
+ * \param trust_ca the list of trusted CAs
+ * \param ca_crl   the list of CRLs for trusted CAs
+ * \param profile  security profile for verification
+ * \param cn       expected Common Name (can be set to
+ *                 NULL if the CN must not be verified)
+ * \param flags    result of the verification
+ * \param f_vrfy   verification function
+ * \param p_vrfy   verification parameter
+ * \param rs_ctx   restart context
+ *
+ * \return         See \c mbedtls_crt_verify_with_profile(), or
+ *                 MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of
+ *                 operations was reached: see \c mbedtls_ecp_set_max_ops().
+ */
+int mbedtls_x509_crt_verify_restartable( mbedtls_x509_crt *crt,
+                     mbedtls_x509_crt *trust_ca,
+                     mbedtls_x509_crl *ca_crl,
+                     const mbedtls_x509_crt_profile *profile,
+                     const char *cn, uint32_t *flags,
+                     int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
+                     void *p_vrfy,
+                     mbedtls_x509_crt_restart_ctx *rs_ctx );
+
 #if defined(MBEDTLS_X509_CHECK_KEY_USAGE)
 /**
  * \brief          Check usage of certificate against keyUsage extension.
@@ -424,6 +512,18 @@
  * \param crt      Certificate chain to free
  */
 void mbedtls_x509_crt_free( mbedtls_x509_crt *crt );
+
+#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
+/**
+ * \brief           Initialize a restart context
+ */
+void mbedtls_x509_crt_restart_init( mbedtls_x509_crt_restart_ctx *ctx );
+
+/**
+ * \brief           Free the components of a restart context
+ */
+void mbedtls_x509_crt_restart_free( mbedtls_x509_crt_restart_ctx *ctx );
+#endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
 #endif /* MBEDTLS_X509_CRT_PARSE_C */
 
 /* \} name */
diff --git a/library/ecdh.c b/library/ecdh.c
index 61380b6..a118de5 100644
--- a/library/ecdh.c
+++ b/library/ecdh.c
@@ -40,13 +40,37 @@
 
 #if !defined(MBEDTLS_ECDH_GEN_PUBLIC_ALT)
 /*
- * Generate public key: simple wrapper around mbedtls_ecp_gen_keypair
+ * Generate public key (restartable version)
+ */
+static int ecdh_gen_public_restartable( mbedtls_ecp_group *grp,
+                    mbedtls_mpi *d, mbedtls_ecp_point *Q,
+                    int (*f_rng)(void *, unsigned char *, size_t),
+                    void *p_rng,
+                    mbedtls_ecp_restart_ctx *rs_ctx )
+{
+    int ret;
+
+    /* If multiplication is in progress, we already generated a privkey */
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    if( rs_ctx == NULL || rs_ctx->rsm == NULL )
+#endif
+        MBEDTLS_MPI_CHK( mbedtls_ecp_gen_privkey( grp, d, f_rng, p_rng ) );
+
+    MBEDTLS_MPI_CHK( mbedtls_ecp_mul_restartable( grp, Q, d, &grp->G,
+                                                  f_rng, p_rng, rs_ctx ) );
+
+cleanup:
+    return( ret );
+}
+
+/*
+ * Generate public key
  */
 int mbedtls_ecdh_gen_public( mbedtls_ecp_group *grp, mbedtls_mpi *d, mbedtls_ecp_point *Q,
                      int (*f_rng)(void *, unsigned char *, size_t),
                      void *p_rng )
 {
-    return mbedtls_ecp_gen_keypair( grp, d, Q, f_rng, p_rng );
+    return( ecdh_gen_public_restartable( grp, d, Q, f_rng, p_rng, NULL ) );
 }
 #endif /* MBEDTLS_ECDH_GEN_PUBLIC_ALT */
 
@@ -54,22 +78,20 @@
 /*
  * Compute shared secret (SEC1 3.3.1)
  */
-int mbedtls_ecdh_compute_shared( mbedtls_ecp_group *grp, mbedtls_mpi *z,
+static int ecdh_compute_shared_restartable( mbedtls_ecp_group *grp,
+                         mbedtls_mpi *z,
                          const mbedtls_ecp_point *Q, const mbedtls_mpi *d,
                          int (*f_rng)(void *, unsigned char *, size_t),
-                         void *p_rng )
+                         void *p_rng,
+                         mbedtls_ecp_restart_ctx *rs_ctx )
 {
     int ret;
     mbedtls_ecp_point P;
 
     mbedtls_ecp_point_init( &P );
 
-    /*
-     * Make sure Q is a valid pubkey before using it
-     */
-    MBEDTLS_MPI_CHK( mbedtls_ecp_check_pubkey( grp, Q ) );
-
-    MBEDTLS_MPI_CHK( mbedtls_ecp_mul( grp, &P, d, Q, f_rng, p_rng ) );
+    MBEDTLS_MPI_CHK( mbedtls_ecp_mul_restartable( grp, &P, d, Q,
+                                                  f_rng, p_rng, rs_ctx ) );
 
     if( mbedtls_ecp_is_zero( &P ) )
     {
@@ -87,11 +109,36 @@
 #endif /* MBEDTLS_ECDH_COMPUTE_SHARED_ALT */
 
 /*
+ * Compute shared secret (SEC1 3.3.1)
+ */
+int mbedtls_ecdh_compute_shared( mbedtls_ecp_group *grp, mbedtls_mpi *z,
+                         const mbedtls_ecp_point *Q, const mbedtls_mpi *d,
+                         int (*f_rng)(void *, unsigned char *, size_t),
+                         void *p_rng )
+{
+    return( ecdh_compute_shared_restartable( grp, z, Q, d,
+                                             f_rng, p_rng, NULL ) );
+}
+
+/*
  * Initialize context
  */
 void mbedtls_ecdh_init( mbedtls_ecdh_context *ctx )
 {
-    memset( ctx, 0, sizeof( mbedtls_ecdh_context ) );
+    mbedtls_ecp_group_init( &ctx->grp );
+    mbedtls_mpi_init( &ctx->d  );
+    mbedtls_ecp_point_init( &ctx->Q   );
+    mbedtls_ecp_point_init( &ctx->Qp  );
+    mbedtls_mpi_init( &ctx->z  );
+    ctx->point_format = MBEDTLS_ECP_PF_UNCOMPRESSED;
+    mbedtls_ecp_point_init( &ctx->Vi  );
+    mbedtls_ecp_point_init( &ctx->Vf  );
+    mbedtls_mpi_init( &ctx->_d );
+
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    ctx->restart_enabled = 0;
+    mbedtls_ecp_restart_init( &ctx->rs );
+#endif
 }
 
 /*
@@ -103,15 +150,31 @@
         return;
 
     mbedtls_ecp_group_free( &ctx->grp );
+    mbedtls_mpi_free( &ctx->d  );
     mbedtls_ecp_point_free( &ctx->Q   );
     mbedtls_ecp_point_free( &ctx->Qp  );
+    mbedtls_mpi_free( &ctx->z  );
     mbedtls_ecp_point_free( &ctx->Vi  );
     mbedtls_ecp_point_free( &ctx->Vf  );
-    mbedtls_mpi_free( &ctx->d  );
-    mbedtls_mpi_free( &ctx->z  );
     mbedtls_mpi_free( &ctx->_d );
+
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    mbedtls_ecp_restart_free( &ctx->rs );
+#endif
+
+    mbedtls_ecdh_init( ctx );
 }
 
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+/*
+ * Enable restartable operations for context
+ */
+void mbedtls_ecdh_enable_restart( mbedtls_ecdh_context *ctx )
+{
+    ctx->restart_enabled = 1;
+}
+#endif
+
 /*
  * Setup and write the ServerKeyExhange parameters (RFC 4492)
  *      struct {
@@ -126,12 +189,18 @@
 {
     int ret;
     size_t grp_len, pt_len;
+    mbedtls_ecp_restart_ctx *rs_ctx = NULL;
 
     if( ctx == NULL || ctx->grp.pbits == 0 )
         return( MBEDTLS_ERR_ECP_BAD_INPUT_DATA );
 
-    if( ( ret = mbedtls_ecdh_gen_public( &ctx->grp, &ctx->d, &ctx->Q, f_rng, p_rng ) )
-                != 0 )
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    if( ctx->restart_enabled )
+        rs_ctx = &ctx->rs;
+#endif
+
+    if( ( ret = ecdh_gen_public_restartable( &ctx->grp, &ctx->d, &ctx->Q,
+                    f_rng, p_rng, rs_ctx ) ) != 0 )
         return( ret );
 
     if( ( ret = mbedtls_ecp_tls_write_group( &ctx->grp, &grp_len, buf, blen ) )
@@ -206,12 +275,18 @@
                       void *p_rng )
 {
     int ret;
+    mbedtls_ecp_restart_ctx *rs_ctx = NULL;
 
     if( ctx == NULL || ctx->grp.pbits == 0 )
         return( MBEDTLS_ERR_ECP_BAD_INPUT_DATA );
 
-    if( ( ret = mbedtls_ecdh_gen_public( &ctx->grp, &ctx->d, &ctx->Q, f_rng, p_rng ) )
-                != 0 )
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    if( ctx->restart_enabled )
+        rs_ctx = &ctx->rs;
+#endif
+
+    if( ( ret = ecdh_gen_public_restartable( &ctx->grp, &ctx->d, &ctx->Q,
+                    f_rng, p_rng, rs_ctx ) ) != 0 )
         return( ret );
 
     return mbedtls_ecp_tls_write_point( &ctx->grp, &ctx->Q, ctx->point_format,
@@ -248,12 +323,18 @@
                       void *p_rng )
 {
     int ret;
+    mbedtls_ecp_restart_ctx *rs_ctx = NULL;
 
-    if( ctx == NULL )
+    if( ctx == NULL || ctx->grp.pbits == 0 )
         return( MBEDTLS_ERR_ECP_BAD_INPUT_DATA );
 
-    if( ( ret = mbedtls_ecdh_compute_shared( &ctx->grp, &ctx->z, &ctx->Qp, &ctx->d,
-                                     f_rng, p_rng ) ) != 0 )
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    if( ctx->restart_enabled )
+        rs_ctx = &ctx->rs;
+#endif
+
+    if( ( ret = ecdh_compute_shared_restartable( &ctx->grp,
+                    &ctx->z, &ctx->Qp, &ctx->d, f_rng, p_rng, rs_ctx ) ) != 0 )
     {
         return( ret );
     }
diff --git a/library/ecdsa.c b/library/ecdsa.c
index 17a88bd..663433c 100644
--- a/library/ecdsa.c
+++ b/library/ecdsa.c
@@ -42,6 +42,180 @@
 #include "mbedtls/hmac_drbg.h"
 #endif
 
+#if defined(MBEDTLS_PLATFORM_C)
+#include "mbedtls/platform.h"
+#else
+#include <stdlib.h>
+#define mbedtls_calloc    calloc
+#define mbedtls_free       free
+#endif
+
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+
+/*
+ * Sub-context for ecdsa_verify()
+ */
+struct mbedtls_ecdsa_restart_ver
+{
+    mbedtls_mpi u1, u2;     /* intermediate values  */
+    enum {                  /* what to do next?     */
+        ecdsa_ver_init = 0, /* getting started      */
+        ecdsa_ver_muladd,   /* muladd step          */
+    } state;
+};
+
+/*
+ * Init verify restart sub-context
+ */
+static void ecdsa_restart_ver_init( mbedtls_ecdsa_restart_ver_ctx *ctx )
+{
+    mbedtls_mpi_init( &ctx->u1 );
+    mbedtls_mpi_init( &ctx->u2 );
+    ctx->state = ecdsa_ver_init;
+}
+
+/*
+ * Free the components of a verify restart sub-context
+ */
+static void ecdsa_restart_ver_free( mbedtls_ecdsa_restart_ver_ctx *ctx )
+{
+    if( ctx == NULL )
+        return;
+
+    mbedtls_mpi_free( &ctx->u1 );
+    mbedtls_mpi_free( &ctx->u2 );
+
+    ecdsa_restart_ver_init( ctx );
+}
+
+/*
+ * Sub-context for ecdsa_sign()
+ */
+struct mbedtls_ecdsa_restart_sig
+{
+    int sign_tries;
+    int key_tries;
+    mbedtls_mpi k;          /* per-signature random */
+    mbedtls_mpi r;          /* r value              */
+    enum {                  /* what to do next?     */
+        ecdsa_sig_init = 0, /* getting started      */
+        ecdsa_sig_mul,      /* doing ecp_mul()      */
+        ecdsa_sig_modn,     /* mod N computations   */
+    } state;
+};
+
+/*
+ * Init verify sign sub-context
+ */
+static void ecdsa_restart_sig_init( mbedtls_ecdsa_restart_sig_ctx *ctx )
+{
+    ctx->sign_tries = 0;
+    ctx->key_tries = 0;
+    mbedtls_mpi_init( &ctx->k );
+    mbedtls_mpi_init( &ctx->r );
+    ctx->state = ecdsa_sig_init;
+}
+
+/*
+ * Free the components of a sign restart sub-context
+ */
+static void ecdsa_restart_sig_free( mbedtls_ecdsa_restart_sig_ctx *ctx )
+{
+    if( ctx == NULL )
+        return;
+
+    mbedtls_mpi_free( &ctx->k );
+    mbedtls_mpi_free( &ctx->r );
+
+    ecdsa_restart_sig_init( ctx );
+}
+
+#if defined(MBEDTLS_ECDSA_DETERMINISTIC)
+/*
+ * Sub-context for ecdsa_sign_det()
+ */
+struct mbedtls_ecdsa_restart_det
+{
+    mbedtls_hmac_drbg_context rng_ctx;  /* DRBG state   */
+    enum {                      /* what to do next?     */
+        ecdsa_det_init = 0,     /* getting started      */
+        ecdsa_det_sign,         /* make signature       */
+    } state;
+};
+
+/*
+ * Init verify sign_det sub-context
+ */
+static void ecdsa_restart_det_init( mbedtls_ecdsa_restart_det_ctx *ctx )
+{
+    mbedtls_hmac_drbg_init( &ctx->rng_ctx );
+    ctx->state = ecdsa_det_init;
+}
+
+/*
+ * Free the components of a sign_det restart sub-context
+ */
+static void ecdsa_restart_det_free( mbedtls_ecdsa_restart_det_ctx *ctx )
+{
+    if( ctx == NULL )
+        return;
+
+    mbedtls_hmac_drbg_free( &ctx->rng_ctx );
+
+    ecdsa_restart_det_init( ctx );
+}
+#endif /* MBEDTLS_ECDSA_DETERMINISTIC */
+
+#define ECDSA_RS_ECP    &rs_ctx->ecp
+
+/* Utility macro for checking and updating ops budget */
+#define ECDSA_BUDGET( ops )   \
+    MBEDTLS_MPI_CHK( mbedtls_ecp_check_budget( grp, &rs_ctx->ecp, ops ) );
+
+/* Call this when entering a function that needs its own sub-context */
+#define ECDSA_RS_ENTER( SUB )   do {                                 \
+    /* reset ops count for this call if top-level */                 \
+    if( rs_ctx != NULL && rs_ctx->ecp.depth++ == 0 )                 \
+        rs_ctx->ecp.ops_done = 0;                                    \
+                                                                     \
+    /* set up our own sub-context if needed */                       \
+    if( mbedtls_ecp_restart_enabled() &&                             \
+        rs_ctx != NULL && rs_ctx->SUB == NULL )                      \
+    {                                                                \
+        rs_ctx->SUB = mbedtls_calloc( 1, sizeof( *rs_ctx->SUB ) );   \
+        if( rs_ctx->SUB == NULL )                                    \
+            return( MBEDTLS_ERR_ECP_ALLOC_FAILED );                  \
+                                                                     \
+        ecdsa_restart_## SUB ##_init( rs_ctx->SUB );                 \
+    }                                                                \
+} while( 0 )
+
+/* Call this when leaving a function that needs its own sub-context */
+#define ECDSA_RS_LEAVE( SUB )   do {                                 \
+    /* clear our sub-context when not in progress (done or error) */ \
+    if( rs_ctx != NULL && rs_ctx->SUB != NULL &&                     \
+        ret != MBEDTLS_ERR_ECP_IN_PROGRESS )                         \
+    {                                                                \
+        ecdsa_restart_## SUB ##_free( rs_ctx->SUB );                 \
+        mbedtls_free( rs_ctx->SUB );                                 \
+        rs_ctx->SUB = NULL;                                          \
+    }                                                                \
+                                                                     \
+    if( rs_ctx != NULL )                                             \
+        rs_ctx->ecp.depth--;                                         \
+} while( 0 )
+
+#else /* MBEDTLS_ECP_RESTARTABLE */
+
+#define ECDSA_RS_ECP    NULL
+
+#define ECDSA_BUDGET( ops )   /* no-op; for compatibility */
+
+#define ECDSA_RS_ENTER( SUB )   (void) rs_ctx
+#define ECDSA_RS_LEAVE( SUB )   (void) rs_ctx
+
+#endif /* MBEDTLS_ECP_RESTARTABLE */
+
 /*
  * Derive a suitable integer for group grp from a buffer of length len
  * SEC1 4.1.3 step 5 aka SEC1 4.1.4 step 3
@@ -70,13 +244,17 @@
  * Compute ECDSA signature of a hashed message (SEC1 4.1.3)
  * Obviously, compared to SEC1 4.1.3, we skip step 4 (hash message)
  */
-int mbedtls_ecdsa_sign( mbedtls_ecp_group *grp, mbedtls_mpi *r, mbedtls_mpi *s,
+static int ecdsa_sign_restartable( mbedtls_ecp_group *grp,
+                mbedtls_mpi *r, mbedtls_mpi *s,
                 const mbedtls_mpi *d, const unsigned char *buf, size_t blen,
-                int (*f_rng)(void *, unsigned char *, size_t), void *p_rng )
+                int (*f_rng)(void *, unsigned char *, size_t), void *p_rng,
+                mbedtls_ecdsa_restart_ctx *rs_ctx )
 {
-    int ret, key_tries, sign_tries, blind_tries;
+    int ret, key_tries, sign_tries;
+    int *p_sign_tries = &sign_tries, *p_key_tries = &key_tries;
     mbedtls_ecp_point R;
     mbedtls_mpi k, e, t;
+    mbedtls_mpi *pk = &k, *pr = r;
 
     /* Fail cleanly on curves such as Curve25519 that can't be used for ECDSA */
     if( grp->N.p == NULL )
@@ -89,26 +267,72 @@
     mbedtls_ecp_point_init( &R );
     mbedtls_mpi_init( &k ); mbedtls_mpi_init( &e ); mbedtls_mpi_init( &t );
 
-    sign_tries = 0;
+    ECDSA_RS_ENTER( sig );
+
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    if( rs_ctx != NULL && rs_ctx->sig != NULL )
+    {
+        /* redirect to our context */
+        p_sign_tries = &rs_ctx->sig->sign_tries;
+        p_key_tries = &rs_ctx->sig->key_tries;
+        pk = &rs_ctx->sig->k;
+        pr = &rs_ctx->sig->r;
+
+        /* jump to current step */
+        if( rs_ctx->sig->state == ecdsa_sig_mul )
+            goto mul;
+        if( rs_ctx->sig->state == ecdsa_sig_modn )
+            goto modn;
+    }
+#endif /* MBEDTLS_ECP_RESTARTABLE */
+
+    *p_sign_tries = 0;
     do
     {
+        if( *p_sign_tries++ > 10 )
+        {
+            ret = MBEDTLS_ERR_ECP_RANDOM_FAILED;
+            goto cleanup;
+        }
+
         /*
          * Steps 1-3: generate a suitable ephemeral keypair
          * and set r = xR mod n
          */
-        key_tries = 0;
+        *p_key_tries = 0;
         do
         {
-            MBEDTLS_MPI_CHK( mbedtls_ecp_gen_keypair( grp, &k, &R, f_rng, p_rng ) );
-            MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( r, &R.X, &grp->N ) );
-
-            if( key_tries++ > 10 )
+            if( *p_key_tries++ > 10 )
             {
                 ret = MBEDTLS_ERR_ECP_RANDOM_FAILED;
                 goto cleanup;
             }
+
+            MBEDTLS_MPI_CHK( mbedtls_ecp_gen_privkey( grp, pk, f_rng, p_rng ) );
+
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+            if( rs_ctx != NULL && rs_ctx->sig != NULL )
+                rs_ctx->sig->state = ecdsa_sig_mul;
+
+mul:
+#endif
+            MBEDTLS_MPI_CHK( mbedtls_ecp_mul_restartable( grp, &R, pk, &grp->G,
+                                                  f_rng, p_rng, ECDSA_RS_ECP ) );
+            MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( pr, &R.X, &grp->N ) );
         }
-        while( mbedtls_mpi_cmp_int( r, 0 ) == 0 );
+        while( mbedtls_mpi_cmp_int( pr, 0 ) == 0 );
+
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+        if( rs_ctx != NULL && rs_ctx->sig != NULL )
+            rs_ctx->sig->state = ecdsa_sig_modn;
+
+modn:
+#endif
+        /*
+         * Accounting for everything up to the end of the loop
+         * (step 6, but checking now avoids saving e and t)
+         */
+        ECDSA_BUDGET( MBEDTLS_ECP_OPS_INV + 4 );
 
         /*
          * Step 5: derive MPI from hashed message
@@ -119,57 +343,60 @@
          * Generate a random value to blind inv_mod in next step,
          * avoiding a potential timing leak.
          */
-        blind_tries = 0;
-        do
-        {
-            size_t n_size = ( grp->nbits + 7 ) / 8;
-            MBEDTLS_MPI_CHK( mbedtls_mpi_fill_random( &t, n_size, f_rng, p_rng ) );
-            MBEDTLS_MPI_CHK( mbedtls_mpi_shift_r( &t, 8 * n_size - grp->nbits ) );
-
-            /* See mbedtls_ecp_gen_keypair() */
-            if( ++blind_tries > 30 )
-                return( MBEDTLS_ERR_ECP_RANDOM_FAILED );
-        }
-        while( mbedtls_mpi_cmp_int( &t, 1 ) < 0 ||
-               mbedtls_mpi_cmp_mpi( &t, &grp->N ) >= 0 );
+        MBEDTLS_MPI_CHK( mbedtls_ecp_gen_privkey( grp, &t, f_rng, p_rng ) );
 
         /*
          * Step 6: compute s = (e + r * d) / k = t (e + rd) / (kt) mod n
          */
-        MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( s, r, d ) );
+        MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( s, pr, d ) );
         MBEDTLS_MPI_CHK( mbedtls_mpi_add_mpi( &e, &e, s ) );
         MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &e, &e, &t ) );
-        MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &k, &k, &t ) );
-        MBEDTLS_MPI_CHK( mbedtls_mpi_inv_mod( s, &k, &grp->N ) );
+        MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( pk, pk, &t ) );
+        MBEDTLS_MPI_CHK( mbedtls_mpi_inv_mod( s, pk, &grp->N ) );
         MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( s, s, &e ) );
         MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( s, s, &grp->N ) );
-
-        if( sign_tries++ > 10 )
-        {
-            ret = MBEDTLS_ERR_ECP_RANDOM_FAILED;
-            goto cleanup;
-        }
     }
     while( mbedtls_mpi_cmp_int( s, 0 ) == 0 );
 
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    if( rs_ctx != NULL && rs_ctx->sig != NULL )
+        mbedtls_mpi_copy( r, pr );
+#endif
+
 cleanup:
     mbedtls_ecp_point_free( &R );
     mbedtls_mpi_free( &k ); mbedtls_mpi_free( &e ); mbedtls_mpi_free( &t );
 
+    ECDSA_RS_LEAVE( sig );
+
     return( ret );
 }
 #endif /* MBEDTLS_ECDSA_SIGN_ALT */
 
+/*
+ * Compute ECDSA signature of a hashed message
+ */
+int mbedtls_ecdsa_sign( mbedtls_ecp_group *grp, mbedtls_mpi *r, mbedtls_mpi *s,
+                const mbedtls_mpi *d, const unsigned char *buf, size_t blen,
+                int (*f_rng)(void *, unsigned char *, size_t), void *p_rng )
+{
+    return( ecdsa_sign_restartable( grp, r, s, d, buf, blen,
+                                    f_rng, p_rng, NULL ) );
+}
+
 #if defined(MBEDTLS_ECDSA_DETERMINISTIC)
 /*
  * Deterministic signature wrapper
  */
-int mbedtls_ecdsa_sign_det( mbedtls_ecp_group *grp, mbedtls_mpi *r, mbedtls_mpi *s,
+static int ecdsa_sign_det_restartable( mbedtls_ecp_group *grp,
+                    mbedtls_mpi *r, mbedtls_mpi *s,
                     const mbedtls_mpi *d, const unsigned char *buf, size_t blen,
-                    mbedtls_md_type_t md_alg )
+                    mbedtls_md_type_t md_alg,
+                    mbedtls_ecdsa_restart_ctx *rs_ctx )
 {
     int ret;
     mbedtls_hmac_drbg_context rng_ctx;
+    mbedtls_hmac_drbg_context *p_rng = &rng_ctx;
     unsigned char data[2 * MBEDTLS_ECP_MAX_BYTES];
     size_t grp_len = ( grp->nbits + 7 ) / 8;
     const mbedtls_md_info_t *md_info;
@@ -181,21 +408,53 @@
     mbedtls_mpi_init( &h );
     mbedtls_hmac_drbg_init( &rng_ctx );
 
+    ECDSA_RS_ENTER( det );
+
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    if( rs_ctx != NULL && rs_ctx->det != NULL )
+    {
+        /* redirect to our context */
+        p_rng = &rs_ctx->det->rng_ctx;
+
+        /* jump to current step */
+        if( rs_ctx->det->state == ecdsa_det_sign )
+            goto sign;
+    }
+#endif /* MBEDTLS_ECP_RESTARTABLE */
+
     /* Use private key and message hash (reduced) to initialize HMAC_DRBG */
     MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( d, data, grp_len ) );
     MBEDTLS_MPI_CHK( derive_mpi( grp, &h, buf, blen ) );
     MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( &h, data + grp_len, grp_len ) );
-    mbedtls_hmac_drbg_seed_buf( &rng_ctx, md_info, data, 2 * grp_len );
+    mbedtls_hmac_drbg_seed_buf( p_rng, md_info, data, 2 * grp_len );
 
-    ret = mbedtls_ecdsa_sign( grp, r, s, d, buf, blen,
-                      mbedtls_hmac_drbg_random, &rng_ctx );
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    if( rs_ctx != NULL && rs_ctx->det != NULL )
+        rs_ctx->det->state = ecdsa_det_sign;
+
+sign:
+#endif
+    ret = ecdsa_sign_restartable( grp, r, s, d, buf, blen,
+                      mbedtls_hmac_drbg_random, p_rng, rs_ctx );
 
 cleanup:
     mbedtls_hmac_drbg_free( &rng_ctx );
     mbedtls_mpi_free( &h );
 
+    ECDSA_RS_LEAVE( det );
+
     return( ret );
 }
+
+/*
+ * Deterministic signature wrapper
+ */
+int mbedtls_ecdsa_sign_det( mbedtls_ecp_group *grp, mbedtls_mpi *r, mbedtls_mpi *s,
+                    const mbedtls_mpi *d, const unsigned char *buf, size_t blen,
+                    mbedtls_md_type_t md_alg )
+{
+    return( ecdsa_sign_det_restartable( grp, r, s, d, buf, blen, md_alg, NULL ) );
+}
 #endif /* MBEDTLS_ECDSA_DETERMINISTIC */
 
 #if !defined(MBEDTLS_ECDSA_VERIFY_ALT)
@@ -203,21 +462,40 @@
  * Verify ECDSA signature of hashed message (SEC1 4.1.4)
  * Obviously, compared to SEC1 4.1.3, we skip step 2 (hash message)
  */
-int mbedtls_ecdsa_verify( mbedtls_ecp_group *grp,
-                  const unsigned char *buf, size_t blen,
-                  const mbedtls_ecp_point *Q, const mbedtls_mpi *r, const mbedtls_mpi *s)
+static int ecdsa_verify_restartable( mbedtls_ecp_group *grp,
+                                     const unsigned char *buf, size_t blen,
+                                     const mbedtls_ecp_point *Q,
+                                     const mbedtls_mpi *r, const mbedtls_mpi *s,
+                                     mbedtls_ecdsa_restart_ctx *rs_ctx )
 {
     int ret;
     mbedtls_mpi e, s_inv, u1, u2;
     mbedtls_ecp_point R;
+    mbedtls_mpi *pu1 = &u1, *pu2 = &u2;
 
     mbedtls_ecp_point_init( &R );
-    mbedtls_mpi_init( &e ); mbedtls_mpi_init( &s_inv ); mbedtls_mpi_init( &u1 ); mbedtls_mpi_init( &u2 );
+    mbedtls_mpi_init( &e ); mbedtls_mpi_init( &s_inv );
+    mbedtls_mpi_init( &u1 ); mbedtls_mpi_init( &u2 );
 
     /* Fail cleanly on curves such as Curve25519 that can't be used for ECDSA */
     if( grp->N.p == NULL )
         return( MBEDTLS_ERR_ECP_BAD_INPUT_DATA );
 
+    ECDSA_RS_ENTER( ver );
+
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    if( rs_ctx != NULL && rs_ctx->ver != NULL )
+    {
+        /* redirect to our context */
+        pu1 = &rs_ctx->ver->u1;
+        pu2 = &rs_ctx->ver->u2;
+
+        /* jump to current step */
+        if( rs_ctx->ver->state == ecdsa_ver_muladd )
+            goto muladd;
+    }
+#endif /* MBEDTLS_ECP_RESTARTABLE */
+
     /*
      * Step 1: make sure r and s are in range 1..n-1
      */
@@ -229,11 +507,6 @@
     }
 
     /*
-     * Additional precaution: make sure Q is valid
-     */
-    MBEDTLS_MPI_CHK( mbedtls_ecp_check_pubkey( grp, Q ) );
-
-    /*
      * Step 3: derive MPI from hashed message
      */
     MBEDTLS_MPI_CHK( derive_mpi( grp, &e, buf, blen ) );
@@ -241,21 +514,27 @@
     /*
      * Step 4: u1 = e / s mod n, u2 = r / s mod n
      */
+    ECDSA_BUDGET( MBEDTLS_ECP_OPS_CHK + MBEDTLS_ECP_OPS_INV + 2 );
+
     MBEDTLS_MPI_CHK( mbedtls_mpi_inv_mod( &s_inv, s, &grp->N ) );
 
-    MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &u1, &e, &s_inv ) );
-    MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &u1, &u1, &grp->N ) );
+    MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( pu1, &e, &s_inv ) );
+    MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( pu1, pu1, &grp->N ) );
 
-    MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &u2, r, &s_inv ) );
-    MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &u2, &u2, &grp->N ) );
+    MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( pu2, r, &s_inv ) );
+    MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( pu2, pu2, &grp->N ) );
 
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    if( rs_ctx != NULL && rs_ctx->ver != NULL )
+        rs_ctx->ver->state = ecdsa_ver_muladd;
+
+muladd:
+#endif
     /*
      * Step 5: R = u1 G + u2 Q
-     *
-     * Since we're not using any secret data, no need to pass a RNG to
-     * mbedtls_ecp_mul() for countermesures.
      */
-    MBEDTLS_MPI_CHK( mbedtls_ecp_muladd( grp, &R, &u1, &grp->G, &u2, Q ) );
+    MBEDTLS_MPI_CHK( mbedtls_ecp_muladd_restartable( grp,
+                     &R, pu1, &grp->G, pu2, Q, ECDSA_RS_ECP ) );
 
     if( mbedtls_ecp_is_zero( &R ) )
     {
@@ -280,13 +559,26 @@
 
 cleanup:
     mbedtls_ecp_point_free( &R );
-    mbedtls_mpi_free( &e ); mbedtls_mpi_free( &s_inv ); mbedtls_mpi_free( &u1 ); mbedtls_mpi_free( &u2 );
+    mbedtls_mpi_free( &e ); mbedtls_mpi_free( &s_inv );
+    mbedtls_mpi_free( &u1 ); mbedtls_mpi_free( &u2 );
+
+    ECDSA_RS_LEAVE( ver );
 
     return( ret );
 }
 #endif /* MBEDTLS_ECDSA_VERIFY_ALT */
 
 /*
+ * Verify ECDSA signature of hashed message
+ */
+int mbedtls_ecdsa_verify( mbedtls_ecp_group *grp,
+                  const unsigned char *buf, size_t blen,
+                  const mbedtls_ecp_point *Q, const mbedtls_mpi *r, const mbedtls_mpi *s)
+{
+    return( ecdsa_verify_restartable( grp, buf, blen, Q, r, s, NULL ) );
+}
+
+/*
  * Convert a signature (given by context) to ASN.1
  */
 static int ecdsa_signature_to_asn1( const mbedtls_mpi *r, const mbedtls_mpi *s,
@@ -313,11 +605,13 @@
 /*
  * Compute and write signature
  */
-int mbedtls_ecdsa_write_signature( mbedtls_ecdsa_context *ctx, mbedtls_md_type_t md_alg,
+int mbedtls_ecdsa_write_signature_restartable( mbedtls_ecdsa_context *ctx,
+                           mbedtls_md_type_t md_alg,
                            const unsigned char *hash, size_t hlen,
                            unsigned char *sig, size_t *slen,
                            int (*f_rng)(void *, unsigned char *, size_t),
-                           void *p_rng )
+                           void *p_rng,
+                           mbedtls_ecdsa_restart_ctx *rs_ctx )
 {
     int ret;
     mbedtls_mpi r, s;
@@ -329,13 +623,13 @@
     (void) f_rng;
     (void) p_rng;
 
-    MBEDTLS_MPI_CHK( mbedtls_ecdsa_sign_det( &ctx->grp, &r, &s, &ctx->d,
-                             hash, hlen, md_alg ) );
+    MBEDTLS_MPI_CHK( ecdsa_sign_det_restartable( &ctx->grp, &r, &s, &ctx->d,
+                             hash, hlen, md_alg, rs_ctx ) );
 #else
     (void) md_alg;
 
-    MBEDTLS_MPI_CHK( mbedtls_ecdsa_sign( &ctx->grp, &r, &s, &ctx->d,
-                         hash, hlen, f_rng, p_rng ) );
+    MBEDTLS_MPI_CHK( ecdsa_sign_restartable( &ctx->grp, &r, &s, &ctx->d,
+                         hash, hlen, f_rng, p_rng, rs_ctx ) );
 #endif
 
     MBEDTLS_MPI_CHK( ecdsa_signature_to_asn1( &r, &s, sig, slen ) );
@@ -347,6 +641,19 @@
     return( ret );
 }
 
+/*
+ * Compute and write signature
+ */
+int mbedtls_ecdsa_write_signature( mbedtls_ecdsa_context *ctx, mbedtls_md_type_t md_alg,
+                           const unsigned char *hash, size_t hlen,
+                           unsigned char *sig, size_t *slen,
+                           int (*f_rng)(void *, unsigned char *, size_t),
+                           void *p_rng )
+{
+    return( mbedtls_ecdsa_write_signature_restartable(
+                ctx, md_alg, hash, hlen, sig, slen, f_rng, p_rng, NULL ) );
+}
+
 #if ! defined(MBEDTLS_DEPRECATED_REMOVED) && \
     defined(MBEDTLS_ECDSA_DETERMINISTIC)
 int mbedtls_ecdsa_write_signature_det( mbedtls_ecdsa_context *ctx,
@@ -366,6 +673,18 @@
                           const unsigned char *hash, size_t hlen,
                           const unsigned char *sig, size_t slen )
 {
+    return( mbedtls_ecdsa_read_signature_restartable(
+                ctx, hash, hlen, sig, slen, NULL ) );
+}
+
+/*
+ * Restartable read and check signature
+ */
+int mbedtls_ecdsa_read_signature_restartable( mbedtls_ecdsa_context *ctx,
+                          const unsigned char *hash, size_t hlen,
+                          const unsigned char *sig, size_t slen,
+                          mbedtls_ecdsa_restart_ctx *rs_ctx )
+{
     int ret;
     unsigned char *p = (unsigned char *) sig;
     const unsigned char *end = sig + slen;
@@ -396,8 +715,8 @@
         goto cleanup;
     }
 
-    if( ( ret = mbedtls_ecdsa_verify( &ctx->grp, hash, hlen,
-                              &ctx->Q, &r, &s ) ) != 0 )
+    if( ( ret = ecdsa_verify_restartable( &ctx->grp, hash, hlen,
+                              &ctx->Q, &r, &s, rs_ctx ) ) != 0 )
         goto cleanup;
 
     /* At this point we know that the buffer starts with a valid signature.
@@ -458,4 +777,42 @@
     mbedtls_ecp_keypair_free( ctx );
 }
 
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+/*
+ * Initialize a restart context
+ */
+void mbedtls_ecdsa_restart_init( mbedtls_ecdsa_restart_ctx *ctx )
+{
+    mbedtls_ecp_restart_init( &ctx->ecp );
+
+    ctx->ver = NULL;
+    ctx->sig = NULL;
+#if defined(MBEDTLS_ECDSA_DETERMINISTIC)
+    ctx->det = NULL;
+#endif
+}
+
+/*
+ * Free the components of a restart context
+ */
+void mbedtls_ecdsa_restart_free( mbedtls_ecdsa_restart_ctx *ctx )
+{
+    mbedtls_ecp_restart_free( &ctx->ecp );
+
+    ecdsa_restart_ver_free( ctx->ver );
+    mbedtls_free( ctx->ver );
+    ctx->ver = NULL;
+
+    ecdsa_restart_sig_free( ctx->sig );
+    mbedtls_free( ctx->sig );
+    ctx->sig = NULL;
+
+#if defined(MBEDTLS_ECDSA_DETERMINISTIC)
+    ecdsa_restart_det_free( ctx->det );
+    mbedtls_free( ctx->det );
+    ctx->det = NULL;
+#endif
+}
+#endif /* MBEDTLS_ECP_RESTARTABLE */
+
 #endif /* MBEDTLS_ECDSA_C */
diff --git a/library/ecp.c b/library/ecp.c
index 41db3fb..52d6d9c 100644
--- a/library/ecp.c
+++ b/library/ecp.c
@@ -82,6 +82,223 @@
 static unsigned long add_count, dbl_count, mul_count;
 #endif
 
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+/*
+ * Maximum number of "basic operations" to be done in a row.
+ *
+ * Default value 0 means that ECC operations will not yield.
+ * Note that regardless of the value of ecp_max_ops, always at
+ * least one step is performed before yielding.
+ *
+ * Setting ecp_max_ops=1 can be suitable for testing purposes
+ * as it will interrupt computation at all possible points.
+ */
+static unsigned ecp_max_ops = 0;
+
+/*
+ * Set ecp_max_ops
+ */
+void mbedtls_ecp_set_max_ops( unsigned max_ops )
+{
+    ecp_max_ops = max_ops;
+}
+
+/*
+ * Check if restart is enabled
+ */
+int mbedtls_ecp_restart_enabled( void )
+{
+    return( ecp_max_ops != 0 );
+}
+
+/*
+ * Restart sub-context for ecp_mul_comb()
+ */
+struct mbedtls_ecp_restart_mul
+{
+    mbedtls_ecp_point R;    /* current intermediate result                  */
+    size_t i;               /* current index in various loops, 0 outside    */
+    mbedtls_ecp_point *T;   /* table for precomputed points                 */
+    unsigned char T_size;   /* number of points in table T                  */
+    enum {                  /* what were we doing last time we returned?    */
+        ecp_rsm_init = 0,       /* nothing so far, dummy initial state      */
+        ecp_rsm_pre_dbl,        /* precompute 2^n multiples                 */
+        ecp_rsm_pre_norm_dbl,   /* normalize precomputed 2^n multiples      */
+        ecp_rsm_pre_add,        /* precompute remaining points by adding    */
+        ecp_rsm_pre_norm_add,   /* normalize all precomputed points         */
+        ecp_rsm_comb_core,      /* ecp_mul_comb_core()                      */
+        ecp_rsm_final_norm,     /* do the final normalization               */
+    } state;
+};
+
+/*
+ * Init restart_mul sub-context
+ */
+static void ecp_restart_rsm_init( mbedtls_ecp_restart_mul_ctx *ctx )
+{
+    mbedtls_ecp_point_init( &ctx->R );
+    ctx->i = 0;
+    ctx->T = NULL;
+    ctx->T_size = 0;
+    ctx->state = ecp_rsm_init;
+}
+
+/*
+ * Free the components of a restart_mul sub-context
+ */
+static void ecp_restart_rsm_free( mbedtls_ecp_restart_mul_ctx *ctx )
+{
+    unsigned char i;
+
+    if( ctx == NULL )
+        return;
+
+    mbedtls_ecp_point_free( &ctx->R );
+
+    if( ctx->T != NULL )
+    {
+        for( i = 0; i < ctx->T_size; i++ )
+            mbedtls_ecp_point_free( ctx->T + i );
+        mbedtls_free( ctx->T );
+    }
+
+    ecp_restart_rsm_init( ctx );
+}
+
+/*
+ * Restart context for ecp_muladd()
+ */
+struct mbedtls_ecp_restart_muladd
+{
+    mbedtls_ecp_point mP;       /* mP value                             */
+    mbedtls_ecp_point R;        /* R intermediate result                */
+    enum {                      /* what should we do next?              */
+        ecp_rsma_mul1 = 0,      /* first multiplication                 */
+        ecp_rsma_mul2,          /* second multiplication                */
+        ecp_rsma_add,           /* addition                             */
+        ecp_rsma_norm,          /* normalization                        */
+    } state;
+};
+
+/*
+ * Init restart_muladd sub-context
+ */
+static void ecp_restart_ma_init( mbedtls_ecp_restart_muladd_ctx *ctx )
+{
+    mbedtls_ecp_point_init( &ctx->mP );
+    mbedtls_ecp_point_init( &ctx->R );
+    ctx->state = ecp_rsma_mul1;
+}
+
+/*
+ * Free the components of a restart_muladd sub-context
+ */
+static void ecp_restart_ma_free( mbedtls_ecp_restart_muladd_ctx *ctx )
+{
+    if( ctx == NULL )
+        return;
+
+    mbedtls_ecp_point_free( &ctx->mP );
+    mbedtls_ecp_point_free( &ctx->R );
+
+    ecp_restart_ma_init( ctx );
+}
+
+/*
+ * Initialize a restart context
+ */
+void mbedtls_ecp_restart_init( mbedtls_ecp_restart_ctx *ctx )
+{
+    ctx->ops_done = 0;
+    ctx->depth = 0;
+    ctx->rsm = NULL;
+    ctx->ma = NULL;
+}
+
+/*
+ * Free the components of a restart context
+ */
+void mbedtls_ecp_restart_free( mbedtls_ecp_restart_ctx *ctx )
+{
+    if( ctx == NULL )
+        return;
+
+    ecp_restart_rsm_free( ctx->rsm );
+    mbedtls_free( ctx->rsm );
+
+    ecp_restart_ma_free( ctx->ma );
+    mbedtls_free( ctx->ma );
+
+    mbedtls_ecp_restart_init( ctx );
+}
+
+/*
+ * Check if we can do the next step
+ */
+int mbedtls_ecp_check_budget( const mbedtls_ecp_group *grp,
+                              mbedtls_ecp_restart_ctx *rs_ctx,
+                              unsigned ops )
+{
+    if( rs_ctx != NULL && ecp_max_ops != 0 )
+    {
+        /* scale depending on curve size: the chosen reference is 256-bit,
+         * and multiplication is quadratic. Round to the closest integer. */
+        if( grp->pbits >= 512 )
+            ops *= 4;
+        else if( grp->pbits >= 384 )
+            ops *= 2;
+
+        /* avoid infinite loops: always allow first step */
+        if( rs_ctx->ops_done != 0 && rs_ctx->ops_done + ops > ecp_max_ops )
+            return( MBEDTLS_ERR_ECP_IN_PROGRESS );
+
+        /* update running count */
+        rs_ctx->ops_done += ops;
+    }
+
+    return( 0 );
+}
+
+/* Call this when entering a function that needs its own sub-context */
+#define ECP_RS_ENTER( SUB )   do {                                 \
+    /* reset ops count for this call if top-level */                 \
+    if( rs_ctx != NULL && rs_ctx->depth++ == 0 )                 \
+        rs_ctx->ops_done = 0;                                    \
+                                                                     \
+    /* set up our own sub-context if needed */                       \
+    if( mbedtls_ecp_restart_enabled() &&                             \
+        rs_ctx != NULL && rs_ctx->SUB == NULL )                      \
+    {                                                                \
+        rs_ctx->SUB = mbedtls_calloc( 1, sizeof( *rs_ctx->SUB ) );   \
+        if( rs_ctx->SUB == NULL )                                    \
+            return( MBEDTLS_ERR_ECP_ALLOC_FAILED );                  \
+                                                                     \
+        ecp_restart_## SUB ##_init( rs_ctx->SUB );                 \
+    }                                                                \
+} while( 0 )
+
+/* Call this when leaving a function that needs its own sub-context */
+#define ECP_RS_LEAVE( SUB )   do {                                 \
+    /* clear our sub-context when not in progress (done or error) */ \
+    if( rs_ctx != NULL && rs_ctx->SUB != NULL &&                     \
+        ret != MBEDTLS_ERR_ECP_IN_PROGRESS )                         \
+    {                                                                \
+        ecp_restart_## SUB ##_free( rs_ctx->SUB );                 \
+        mbedtls_free( rs_ctx->SUB );                                 \
+        rs_ctx->SUB = NULL;                                          \
+    }                                                                \
+                                                                     \
+    if( rs_ctx != NULL )                                             \
+        rs_ctx->depth--;                                         \
+} while( 0 )
+
+#else /* MBEDTLS_ECP_RESTARTABLE */
+
+#define ECP_RS_ENTER( sub )     (void) rs_ctx;
+#define ECP_RS_LEAVE( sub )     (void) rs_ctx;
+
+#endif /* MBEDTLS_ECP_RESTARTABLE */
+
 #if defined(MBEDTLS_ECP_DP_SECP192R1_ENABLED) ||   \
     defined(MBEDTLS_ECP_DP_SECP224R1_ENABLED) ||   \
     defined(MBEDTLS_ECP_DP_SECP256R1_ENABLED) ||   \
@@ -289,7 +506,21 @@
     if( grp == NULL )
         return;
 
-    memset( grp, 0, sizeof( mbedtls_ecp_group ) );
+    grp->id = 0;
+    mbedtls_mpi_init( &grp->P );
+    mbedtls_mpi_init( &grp->A );
+    mbedtls_mpi_init( &grp->B );
+    mbedtls_ecp_point_init( &grp->G );
+    mbedtls_mpi_init( &grp->N );
+    grp->pbits = 0;
+    grp->nbits = 0;
+    grp->h = 0;
+    grp->modp = NULL;
+    grp->t_pre = NULL;
+    grp->t_post = NULL;
+    grp->t_data = NULL;
+    grp->T = NULL;
+    grp->T_size = 0;
 }
 
 /*
@@ -752,11 +983,10 @@
         return( 0 );
 
 #if defined(MBEDTLS_ECP_NORMALIZE_JAC_ALT)
-    if ( mbedtls_internal_ecp_grp_capable( grp ) )
-    {
-        return mbedtls_internal_ecp_normalize_jac( grp, pt );
-    }
+    if( mbedtls_internal_ecp_grp_capable( grp ) )
+        return( mbedtls_internal_ecp_normalize_jac( grp, pt ) );
 #endif /* MBEDTLS_ECP_NORMALIZE_JAC_ALT */
+
     mbedtls_mpi_init( &Zi ); mbedtls_mpi_init( &ZZi );
 
     /*
@@ -796,32 +1026,33 @@
  * Cost: 1N(t) := 1I + (6t - 3)M + 1S
  */
 static int ecp_normalize_jac_many( const mbedtls_ecp_group *grp,
-                                   mbedtls_ecp_point *T[], size_t t_len )
+                                   mbedtls_ecp_point *T[], size_t T_size )
 {
     int ret;
     size_t i;
     mbedtls_mpi *c, u, Zi, ZZi;
 
-    if( t_len < 2 )
+    if( T_size < 2 )
         return( ecp_normalize_jac( grp, *T ) );
 
 #if defined(MBEDTLS_ECP_NORMALIZE_JAC_MANY_ALT)
-    if ( mbedtls_internal_ecp_grp_capable( grp ) )
-    {
-        return mbedtls_internal_ecp_normalize_jac_many(grp, T, t_len);
-    }
+    if( mbedtls_internal_ecp_grp_capable( grp ) )
+        return( mbedtls_internal_ecp_normalize_jac_many( grp, T, T_size ) );
 #endif
 
-    if( ( c = mbedtls_calloc( t_len, sizeof( mbedtls_mpi ) ) ) == NULL )
+    if( ( c = mbedtls_calloc( T_size, sizeof( mbedtls_mpi ) ) ) == NULL )
         return( MBEDTLS_ERR_ECP_ALLOC_FAILED );
 
+    for( i = 0; i < T_size; i++ )
+        mbedtls_mpi_init( &c[i] );
+
     mbedtls_mpi_init( &u ); mbedtls_mpi_init( &Zi ); mbedtls_mpi_init( &ZZi );
 
     /*
      * c[i] = Z_0 * ... * Z_i
      */
     MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &c[0], &T[0]->Z ) );
-    for( i = 1; i < t_len; i++ )
+    for( i = 1; i < T_size; i++ )
     {
         MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &c[i], &c[i-1], &T[i]->Z ) );
         MOD_MUL( c[i] );
@@ -830,9 +1061,9 @@
     /*
      * u = 1 / (Z_0 * ... * Z_n) mod P
      */
-    MBEDTLS_MPI_CHK( mbedtls_mpi_inv_mod( &u, &c[t_len-1], &grp->P ) );
+    MBEDTLS_MPI_CHK( mbedtls_mpi_inv_mod( &u, &c[T_size-1], &grp->P ) );
 
-    for( i = t_len - 1; ; i-- )
+    for( i = T_size - 1; ; i-- )
     {
         /*
          * Zi = 1 / Z_i mod p
@@ -872,7 +1103,7 @@
 cleanup:
 
     mbedtls_mpi_free( &u ); mbedtls_mpi_free( &Zi ); mbedtls_mpi_free( &ZZi );
-    for( i = 0; i < t_len; i++ )
+    for( i = 0; i < T_size; i++ )
         mbedtls_mpi_free( &c[i] );
     mbedtls_free( c );
 
@@ -929,10 +1160,8 @@
 #endif
 
 #if defined(MBEDTLS_ECP_DOUBLE_JAC_ALT)
-    if ( mbedtls_internal_ecp_grp_capable( grp ) )
-    {
-        return mbedtls_internal_ecp_double_jac( grp, R, P );
-    }
+    if( mbedtls_internal_ecp_grp_capable( grp ) )
+        return( mbedtls_internal_ecp_double_jac( grp, R, P ) );
 #endif /* MBEDTLS_ECP_DOUBLE_JAC_ALT */
 
     mbedtls_mpi_init( &M ); mbedtls_mpi_init( &S ); mbedtls_mpi_init( &T ); mbedtls_mpi_init( &U );
@@ -1027,10 +1256,8 @@
 #endif
 
 #if defined(MBEDTLS_ECP_ADD_MIXED_ALT)
-    if ( mbedtls_internal_ecp_grp_capable( grp ) )
-    {
-        return mbedtls_internal_ecp_add_mixed( grp, R, P, Q );
-    }
+    if( mbedtls_internal_ecp_grp_capable( grp ) )
+        return( mbedtls_internal_ecp_add_mixed( grp, R, P, Q ) );
 #endif /* MBEDTLS_ECP_ADD_MIXED_ALT */
 
     /*
@@ -1114,10 +1341,8 @@
     int count = 0;
 
 #if defined(MBEDTLS_ECP_RANDOMIZE_JAC_ALT)
-    if ( mbedtls_internal_ecp_grp_capable( grp ) )
-    {
-        return mbedtls_internal_ecp_randomize_jac( grp, pt, f_rng, p_rng );
-    }
+    if( mbedtls_internal_ecp_grp_capable( grp ) )
+        return( mbedtls_internal_ecp_randomize_jac( grp, pt, f_rng, p_rng ) );
 #endif /* MBEDTLS_ECP_RANDOMIZE_JAC_ALT */
 
     p_size = ( grp->pbits + 7 ) / 8;
@@ -1173,11 +1398,38 @@
  * modified version that provides resistance to SPA by avoiding zero
  * digits in the representation as in [3]. We modify the method further by
  * requiring that all K_i be odd, which has the small cost that our
- * representation uses one more K_i, due to carries.
+ * representation uses one more K_i, due to carries, but saves on the size of
+ * the precomputed table.
  *
- * Also, for the sake of compactness, only the seven low-order bits of x[i]
- * are used to represent K_i, and the msb of x[i] encodes the the sign (s_i in
- * the paper): it is set if and only if if s_i == -1;
+ * Summary of the comb method and its modifications:
+ *
+ * - The goal is to compute m*P for some w*d-bit integer m.
+ *
+ * - The basic comb method splits m into the w-bit integers
+ *   x[0] .. x[d-1] where x[i] consists of the bits in m whose
+ *   index has residue i modulo d, and computes m * P as
+ *   S[x[0]] + 2 * S[x[1]] + .. + 2^(d-1) S[x[d-1]], where
+ *   S[i_{w-1} .. i_0] := i_{w-1} 2^{(w-1)d} P + ... + i_1 2^d P + i_0 P.
+ *
+ * - If it happens that, say, x[i+1]=0 (=> S[x[i+1]]=0), one can replace the sum by
+ *    .. + 2^{i-1} S[x[i-1]] - 2^i S[x[i]] + 2^{i+1} S[x[i]] + 2^{i+2} S[x[i+2]] ..,
+ *   thereby successively converting it into a form where all summands
+ *   are nonzero, at the cost of negative summands. This is the basic idea of [3].
+ *
+ * - More generally, even if x[i+1] != 0, we can first transform the sum as
+ *   .. - 2^i S[x[i]] + 2^{i+1} ( S[x[i]] + S[x[i+1]] ) + 2^{i+2} S[x[i+2]] ..,
+ *   and then replace S[x[i]] + S[x[i+1]] = S[x[i] ^ x[i+1]] + 2 S[x[i] & x[i+1]].
+ *   Performing and iterating this procedure for those x[i] that are even
+ *   (keeping track of carry), we can transform the original sum into one of the form
+ *   S[x'[0]] +- 2 S[x'[1]] +- .. +- 2^{d-1} S[x'[d-1]] + 2^d S[x'[d]]
+ *   with all x'[i] odd. It is therefore only necessary to know S at odd indices,
+ *   which is why we are only computing half of it in the first place in
+ *   ecp_precompute_comb and accessing it with index abs(i) / 2 in ecp_select_comb.
+ *
+ * - For the sake of compactness, only the seven low-order bits of x[i]
+ *   are used to represent its absolute value (K_i in the paper), and the msb
+ *   of x[i] encodes the the sign (s_i in the paper): it is set if and only if
+ *   if s_i == -1;
  *
  * Calling conventions:
  * - x is an array of size d + 1
@@ -1186,8 +1438,8 @@
  * - m is the MPI, expected to be odd and such that bitlength(m) <= w * d
  *   (the result will be incorrect if these assumptions are not satisfied)
  */
-static void ecp_comb_fixed( unsigned char x[], size_t d,
-                            unsigned char w, const mbedtls_mpi *m )
+static void ecp_comb_recode_core( unsigned char x[], size_t d,
+                                  unsigned char w, const mbedtls_mpi *m )
 {
     size_t i, j;
     unsigned char c, cc, adjust;
@@ -1217,70 +1469,184 @@
 }
 
 /*
- * Precompute points for the comb method
+ * Precompute points for the adapted comb method
  *
- * If i = i_{w-1} ... i_1 is the binary representation of i, then
- * T[i] = i_{w-1} 2^{(w-1)d} P + ... + i_1 2^d P + P
+ * Assumption: T must be able to hold 2^{w - 1} elements.
  *
- * T must be able to hold 2^{w - 1} elements
+ * Operation: If i = i_{w-1} ... i_1 is the binary representation of i,
+ *            sets T[i] = i_{w-1} 2^{(w-1)d} P + ... + i_1 2^d P + P.
  *
  * Cost: d(w-1) D + (2^{w-1} - 1) A + 1 N(w-1) + 1 N(2^{w-1} - 1)
+ *
+ * Note: Even comb values (those where P would be omitted from the
+ *       sum defining T[i] above) are not needed in our adaption
+ *       the the comb method. See ecp_comb_recode_core().
+ *
+ * This function currently works in four steps:
+ * (1) [dbl]      Computation of intermediate T[i] for 2-powers values of i
+ * (2) [norm_dbl] Normalization of coordinates of these T[i]
+ * (3) [add]      Computation of all T[i]
+ * (4) [norm_add] Normalization of all T[i]
+ *
+ * Step 1 can be interrupted but not the others; together with the final
+ * coordinate normalization they are the largest steps done at once, depending
+ * on the window size. Here are operation counts for P-256:
+ *
+ * step     (2)     (3)     (4)
+ * w = 5    142     165     208
+ * w = 4    136      77     160
+ * w = 3    130      33     136
+ * w = 2    124      11     124
+ *
+ * So if ECC operations are blocking for too long even with a low max_ops
+ * value, it's useful to set MBEDTLS_ECP_WINDOW_SIZE to a lower value in order
+ * to minimize maximum blocking time.
  */
 static int ecp_precompute_comb( const mbedtls_ecp_group *grp,
                                 mbedtls_ecp_point T[], const mbedtls_ecp_point *P,
-                                unsigned char w, size_t d )
+                                unsigned char w, size_t d,
+                                mbedtls_ecp_restart_ctx *rs_ctx )
 {
     int ret;
-    unsigned char i, k;
-    size_t j;
+    unsigned char i;
+    size_t j = 0;
+    const unsigned char T_size = 1U << ( w - 1 );
     mbedtls_ecp_point *cur, *TT[COMB_MAX_PRE - 1];
 
+#if !defined(MBEDTLS_ECP_RESTARTABLE)
+    (void) rs_ctx;
+#endif
+
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    if( rs_ctx != NULL && rs_ctx->rsm != NULL )
+    {
+        if( rs_ctx->rsm->state == ecp_rsm_pre_dbl )
+            goto dbl;
+        if( rs_ctx->rsm->state == ecp_rsm_pre_norm_dbl )
+            goto norm_dbl;
+        if( rs_ctx->rsm->state == ecp_rsm_pre_add )
+            goto add;
+        if( rs_ctx->rsm->state == ecp_rsm_pre_norm_add )
+            goto norm_add;
+    }
+#endif
+
     /*
      * Set T[0] = P and
      * T[2^{l-1}] = 2^{dl} P for l = 1 .. w-1 (this is not the final value)
      */
-    MBEDTLS_MPI_CHK( mbedtls_ecp_copy( &T[0], P ) );
-
-    k = 0;
-    for( i = 1; i < ( 1U << ( w - 1 ) ); i <<= 1 )
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    if( rs_ctx != NULL && rs_ctx->rsm != NULL )
     {
-        cur = T + i;
-        MBEDTLS_MPI_CHK( mbedtls_ecp_copy( cur, T + ( i >> 1 ) ) );
-        for( j = 0; j < d; j++ )
-            MBEDTLS_MPI_CHK( ecp_double_jac( grp, cur, cur ) );
+        rs_ctx->rsm->state = ecp_rsm_pre_dbl;
 
-        TT[k++] = cur;
+        /* initial state for the loop */
+        rs_ctx->rsm->i = 0;
     }
 
-    MBEDTLS_MPI_CHK( ecp_normalize_jac_many( grp, TT, k ) );
+dbl:
+#endif
+
+    MBEDTLS_MPI_CHK( mbedtls_ecp_copy( &T[0], P ) );
+
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    if( rs_ctx != NULL && rs_ctx->rsm != NULL && rs_ctx->rsm->i != 0 )
+        j = rs_ctx->rsm->i;
+    else
+#endif
+        j = 0;
+
+    for( ; j < d * ( w - 1 ); j++ )
+    {
+        MBEDTLS_ECP_BUDGET( MBEDTLS_ECP_OPS_DBL );
+
+        i = 1U << ( j / d );
+        cur = T + i;
+
+        if( j % d == 0 )
+            MBEDTLS_MPI_CHK( mbedtls_ecp_copy( cur, T + ( i >> 1 ) ) );
+
+        MBEDTLS_MPI_CHK( ecp_double_jac( grp, cur, cur ) );
+    }
+
+    /*
+     * Normalize current elements in T. As T has holes,
+     * use an auxiliary array of pointers to elements in T.
+     */
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    if( rs_ctx != NULL && rs_ctx->rsm != NULL )
+        rs_ctx->rsm->state = ecp_rsm_pre_norm_dbl;
+
+norm_dbl:
+#endif
+
+    j = 0;
+    for( i = 1; i < T_size; i <<= 1 )
+        TT[j++] = T + i;
+
+    MBEDTLS_ECP_BUDGET( MBEDTLS_ECP_OPS_INV + 6 * j - 2 );
+
+    MBEDTLS_MPI_CHK( ecp_normalize_jac_many( grp, TT, j ) );
 
     /*
      * Compute the remaining ones using the minimal number of additions
      * Be careful to update T[2^l] only after using it!
      */
-    k = 0;
-    for( i = 1; i < ( 1U << ( w - 1 ) ); i <<= 1 )
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    if( rs_ctx != NULL && rs_ctx->rsm != NULL )
+        rs_ctx->rsm->state = ecp_rsm_pre_add;
+
+add:
+#endif
+
+    MBEDTLS_ECP_BUDGET( ( T_size - 1 ) * MBEDTLS_ECP_OPS_ADD );
+
+    for( i = 1; i < T_size; i <<= 1 )
     {
         j = i;
         while( j-- )
-        {
             MBEDTLS_MPI_CHK( ecp_add_mixed( grp, &T[i + j], &T[j], &T[i] ) );
-            TT[k++] = &T[i + j];
-        }
     }
 
-    MBEDTLS_MPI_CHK( ecp_normalize_jac_many( grp, TT, k ) );
+    /*
+     * Normalize final elements in T. Even though there are no holes now,
+     * we still need the auxiliary array for homogeneity with last time.
+     * Also, skip T[0] which is already normalised, being a copy of P.
+     */
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    if( rs_ctx != NULL && rs_ctx->rsm != NULL )
+        rs_ctx->rsm->state = ecp_rsm_pre_norm_add;
+
+norm_add:
+#endif
+
+    for( j = 0; j + 1 < T_size; j++ )
+        TT[j] = T + j + 1;
+
+    MBEDTLS_ECP_BUDGET( MBEDTLS_ECP_OPS_INV + 6 * j - 2 );
+
+    MBEDTLS_MPI_CHK( ecp_normalize_jac_many( grp, TT, j ) );
 
 cleanup:
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    if( rs_ctx != NULL && rs_ctx->rsm != NULL &&
+        ret == MBEDTLS_ERR_ECP_IN_PROGRESS )
+    {
+        if( rs_ctx->rsm->state == ecp_rsm_pre_dbl )
+            rs_ctx->rsm->i = j;
+    }
+#endif
 
     return( ret );
 }
 
 /*
  * Select precomputed point: R = sign(i) * T[ abs(i) / 2 ]
+ *
+ * See ecp_comb_recode_core() for background
  */
 static int ecp_select_comb( const mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
-                            const mbedtls_ecp_point T[], unsigned char t_len,
+                            const mbedtls_ecp_point T[], unsigned char T_size,
                             unsigned char i )
 {
     int ret;
@@ -1290,7 +1656,7 @@
     ii =  ( i & 0x7Fu ) >> 1;
 
     /* Read the whole table to thwart cache-based timing attacks */
-    for( j = 0; j < t_len; j++ )
+    for( j = 0; j < T_size; j++ )
     {
         MBEDTLS_MPI_CHK( mbedtls_mpi_safe_cond_assign( &R->X, &T[j].X, j == ii ) );
         MBEDTLS_MPI_CHK( mbedtls_mpi_safe_cond_assign( &R->Y, &T[j].Y, j == ii ) );
@@ -1310,10 +1676,11 @@
  * Cost: d A + d D + 1 R
  */
 static int ecp_mul_comb_core( const mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
-                              const mbedtls_ecp_point T[], unsigned char t_len,
+                              const mbedtls_ecp_point T[], unsigned char T_size,
                               const unsigned char x[], size_t d,
                               int (*f_rng)(void *, unsigned char *, size_t),
-                              void *p_rng )
+                              void *p_rng,
+                              mbedtls_ecp_restart_ctx *rs_ctx )
 {
     int ret;
     mbedtls_ecp_point Txi;
@@ -1321,17 +1688,40 @@
 
     mbedtls_ecp_point_init( &Txi );
 
-    /* Start with a non-zero point and randomize its coordinates */
-    i = d;
-    MBEDTLS_MPI_CHK( ecp_select_comb( grp, R, T, t_len, x[i] ) );
-    MBEDTLS_MPI_CHK( mbedtls_mpi_lset( &R->Z, 1 ) );
-    if( f_rng != 0 )
-        MBEDTLS_MPI_CHK( ecp_randomize_jac( grp, R, f_rng, p_rng ) );
+#if !defined(MBEDTLS_ECP_RESTARTABLE)
+    (void) rs_ctx;
+#endif
+
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    if( rs_ctx != NULL && rs_ctx->rsm != NULL &&
+        rs_ctx->rsm->state != ecp_rsm_comb_core )
+    {
+        rs_ctx->rsm->i = 0;
+        rs_ctx->rsm->state = ecp_rsm_comb_core;
+    }
+
+    /* new 'if' instead of nested for the sake of the 'else' branch */
+    if( rs_ctx != NULL && rs_ctx->rsm != NULL && rs_ctx->rsm->i != 0 )
+    {
+        /* restore current index (R already pointing to rs_ctx->rsm->R) */
+        i = rs_ctx->rsm->i;
+    }
+    else
+#endif
+    {
+        /* Start with a non-zero point and randomize its coordinates */
+        i = d;
+        MBEDTLS_MPI_CHK( ecp_select_comb( grp, R, T, T_size, x[i] ) );
+        MBEDTLS_MPI_CHK( mbedtls_mpi_lset( &R->Z, 1 ) );
+        if( f_rng != 0 )
+            MBEDTLS_MPI_CHK( ecp_randomize_jac( grp, R, f_rng, p_rng ) );
+    }
 
     while( i-- != 0 )
     {
+        MBEDTLS_ECP_BUDGET( MBEDTLS_ECP_OPS_DBL + MBEDTLS_ECP_OPS_ADD );
         MBEDTLS_MPI_CHK( ecp_double_jac( grp, R, R ) );
-        MBEDTLS_MPI_CHK( ecp_select_comb( grp, &Txi, T, t_len, x[i] ) );
+        MBEDTLS_MPI_CHK( ecp_select_comb( grp, &Txi, T, T_size, x[i] ) );
         MBEDTLS_MPI_CHK( ecp_add_mixed( grp, R, R, &Txi ) );
     }
 
@@ -1339,32 +1729,131 @@
 
     mbedtls_ecp_point_free( &Txi );
 
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    if( rs_ctx != NULL && rs_ctx->rsm != NULL &&
+        ret == MBEDTLS_ERR_ECP_IN_PROGRESS )
+    {
+        /* was decreased before actually doing it */
+        rs_ctx->rsm->i = i + 1;
+        /* no need to save R, already pointing to rs_ctx->rsm->R */
+    }
+#endif
+
     return( ret );
 }
 
 /*
- * Multiplication using the comb method,
- * for curves in short Weierstrass form
+ * Recode the scalar to get constant-time comb multiplication
+ *
+ * As the actual scalar recoding needs an odd scalar as a starting point,
+ * this wrapper ensures that by replacing m by N - m if necessary, and
+ * informs the caller that the result of multiplication will be negated.
+ *
+ * This works because we only support large prime order for Short Weierstrass
+ * curves, so N is always odd hence either m or N - m is.
+ *
+ * See ecp_comb_recode_core() for background.
  */
-static int ecp_mul_comb( mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
-                         const mbedtls_mpi *m, const mbedtls_ecp_point *P,
-                         int (*f_rng)(void *, unsigned char *, size_t),
-                         void *p_rng )
+static int ecp_comb_recode_scalar( const mbedtls_ecp_group *grp,
+                                   const mbedtls_mpi *m,
+                                   unsigned char k[COMB_MAX_D + 1],
+                                   size_t d,
+                                   unsigned char w,
+                                   unsigned char *parity_trick )
 {
     int ret;
-    unsigned char w, m_is_odd, p_eq_g, pre_len, i;
-    size_t d;
-    unsigned char k[COMB_MAX_D + 1];
-    mbedtls_ecp_point *T;
     mbedtls_mpi M, mm;
 
     mbedtls_mpi_init( &M );
     mbedtls_mpi_init( &mm );
 
-    /* we need N to be odd to trnaform m in an odd number, check now */
+    /* N is always odd (see above), just make extra sure */
     if( mbedtls_mpi_get_bit( &grp->N, 0 ) != 1 )
         return( MBEDTLS_ERR_ECP_BAD_INPUT_DATA );
 
+    /* do we need the parity trick? */
+    *parity_trick = ( mbedtls_mpi_get_bit( m, 0 ) == 0 );
+
+    /* execute parity fix in constant time */
+    MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &M, m ) );
+    MBEDTLS_MPI_CHK( mbedtls_mpi_sub_mpi( &mm, &grp->N, m ) );
+    MBEDTLS_MPI_CHK( mbedtls_mpi_safe_cond_assign( &M, &mm, *parity_trick ) );
+
+    /* actual scalar recoding */
+    ecp_comb_recode_core( k, d, w, &M );
+
+cleanup:
+    mbedtls_mpi_free( &mm );
+    mbedtls_mpi_free( &M );
+
+    return( ret );
+}
+
+/*
+ * Perform comb multiplication (for short Weierstrass curves)
+ * once the auxiliary table has been pre-computed.
+ *
+ * Scalar recoding may use a parity trick that makes us compute -m * P,
+ * if that is the case we'll need to recover m * P at the end.
+ */
+static int ecp_mul_comb_after_precomp( const mbedtls_ecp_group *grp,
+                                mbedtls_ecp_point *R,
+                                const mbedtls_mpi *m,
+                                const mbedtls_ecp_point *T,
+                                unsigned char T_size,
+                                unsigned char w,
+                                size_t d,
+                                int (*f_rng)(void *, unsigned char *, size_t),
+                                void *p_rng,
+                                mbedtls_ecp_restart_ctx *rs_ctx )
+{
+    int ret;
+    unsigned char parity_trick;
+    unsigned char k[COMB_MAX_D + 1];
+    mbedtls_ecp_point *RR = R;
+
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    if( rs_ctx != NULL && rs_ctx->rsm != NULL )
+    {
+        RR = &rs_ctx->rsm->R;
+
+        if( rs_ctx->rsm->state == ecp_rsm_final_norm )
+            goto final_norm;
+    }
+#endif
+
+    MBEDTLS_MPI_CHK( ecp_comb_recode_scalar( grp, m, k, d, w,
+                                            &parity_trick ) );
+    MBEDTLS_MPI_CHK( ecp_mul_comb_core( grp, RR, T, T_size, k, d,
+                                        f_rng, p_rng, rs_ctx ) );
+    MBEDTLS_MPI_CHK( ecp_safe_invert_jac( grp, RR, parity_trick ) );
+
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    if( rs_ctx != NULL && rs_ctx->rsm != NULL )
+        rs_ctx->rsm->state = ecp_rsm_final_norm;
+
+final_norm:
+#endif
+    MBEDTLS_ECP_BUDGET( MBEDTLS_ECP_OPS_INV );
+    MBEDTLS_MPI_CHK( ecp_normalize_jac( grp, RR ) );
+
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    if( rs_ctx != NULL && rs_ctx->rsm != NULL )
+        MBEDTLS_MPI_CHK( mbedtls_ecp_copy( R, RR ) );
+#endif
+
+cleanup:
+    return( ret );
+}
+
+/*
+ * Pick window size based on curve size and whether we optimize for base point
+ */
+static unsigned char ecp_pick_window_size( const mbedtls_ecp_group *grp,
+                                           unsigned char p_eq_g )
+{
+    unsigned char w;
+
     /*
      * Minimize the number of multiplications, that is minimize
      * 10 * d * w + 18 * 2^(w-1) + 11 * d + 7 * w, with d = ceil( nbits / w )
@@ -1377,14 +1866,8 @@
      * Just adding one avoids upping the cost of the first mul too much,
      * and the memory cost too.
      */
-#if MBEDTLS_ECP_FIXED_POINT_OPTIM == 1
-    p_eq_g = ( mbedtls_mpi_cmp_mpi( &P->Y, &grp->G.Y ) == 0 &&
-               mbedtls_mpi_cmp_mpi( &P->X, &grp->G.X ) == 0 );
     if( p_eq_g )
         w++;
-#else
-    p_eq_g = 0;
-#endif
 
     /*
      * Make sure w is within bounds.
@@ -1395,70 +1878,139 @@
     if( w >= grp->nbits )
         w = 2;
 
-    /* Other sizes that depend on w */
-    pre_len = 1U << ( w - 1 );
+    return( w );
+}
+
+/*
+ * Multiplication using the comb method - for curves in short Weierstrass form
+ *
+ * This function is mainly responsible for administrative work:
+ * - managing the restart context if enabled
+ * - managing the table of precomputed points (passed between the below two
+ *   functions): allocation, computation, ownership tranfer, freeing.
+ *
+ * It delegates the actual arithmetic work to:
+ *      ecp_precompute_comb() and ecp_mul_comb_with_precomp()
+ *
+ * See comments on ecp_comb_recode_core() regarding the computation strategy.
+ */
+static int ecp_mul_comb( mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
+                         const mbedtls_mpi *m, const mbedtls_ecp_point *P,
+                         int (*f_rng)(void *, unsigned char *, size_t),
+                         void *p_rng,
+                         mbedtls_ecp_restart_ctx *rs_ctx )
+{
+    int ret;
+    unsigned char w, p_eq_g, i;
+    size_t d;
+    unsigned char T_size, T_ok;
+    mbedtls_ecp_point *T;
+
+    ECP_RS_ENTER( rsm );
+
+    /* Is P the base point ? */
+#if MBEDTLS_ECP_FIXED_POINT_OPTIM == 1
+    p_eq_g = ( mbedtls_mpi_cmp_mpi( &P->Y, &grp->G.Y ) == 0 &&
+               mbedtls_mpi_cmp_mpi( &P->X, &grp->G.X ) == 0 );
+#else
+    p_eq_g = 0;
+#endif
+
+    /* Pick window size and deduce related sizes */
+    w = ecp_pick_window_size( grp, p_eq_g );
+    T_size = 1U << ( w - 1 );
     d = ( grp->nbits + w - 1 ) / w;
 
-    /*
-     * Prepare precomputed points: if P == G we want to
-     * use grp->T if already initialized, or initialize it.
-     */
-    T = p_eq_g ? grp->T : NULL;
-
-    if( T == NULL )
+    /* Pre-computed table: do we have it already for the base point? */
+    if( p_eq_g && grp->T != NULL )
     {
-        T = mbedtls_calloc( pre_len, sizeof( mbedtls_ecp_point ) );
+        /* second pointer to the same table, will be deleted on exit */
+        T = grp->T;
+        T_ok = 1;
+    }
+    else
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    /* Pre-computed table: do we have one in progress? complete? */
+    if( rs_ctx != NULL && rs_ctx->rsm != NULL && rs_ctx->rsm->T != NULL )
+    {
+        /* transfer ownership of T from rsm to local function */
+        T = rs_ctx->rsm->T;
+        rs_ctx->rsm->T = NULL;
+        rs_ctx->rsm->T_size = 0;
+
+        T_ok = rs_ctx->rsm->state >= ecp_rsm_comb_core;
+    }
+    else
+#endif
+    /* Allocate table if we didn't have any */
+    {
+        T = mbedtls_calloc( T_size, sizeof( mbedtls_ecp_point ) );
         if( T == NULL )
         {
             ret = MBEDTLS_ERR_ECP_ALLOC_FAILED;
             goto cleanup;
         }
 
-        MBEDTLS_MPI_CHK( ecp_precompute_comb( grp, T, P, w, d ) );
+        for( i = 0; i < T_size; i++ )
+            mbedtls_ecp_point_init( &T[i] );
+
+        T_ok = 0;
+    }
+
+    /* Compute table (or finish computing it) if not done already */
+    if( !T_ok )
+    {
+        MBEDTLS_MPI_CHK( ecp_precompute_comb( grp, T, P, w, d, rs_ctx ) );
 
         if( p_eq_g )
         {
+            /* almost transfer ownership of T to the group, but keep a copy of
+             * the pointer to use for caling the next function more easily */
             grp->T = T;
-            grp->T_size = pre_len;
+            grp->T_size = T_size;
         }
     }
 
-    /*
-     * Make sure M is odd (M = m or M = N - m, since N is odd)
-     * using the fact that m * P = - (N - m) * P
-     */
-    m_is_odd = ( mbedtls_mpi_get_bit( m, 0 ) == 1 );
-    MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &M, m ) );
-    MBEDTLS_MPI_CHK( mbedtls_mpi_sub_mpi( &mm, &grp->N, m ) );
-    MBEDTLS_MPI_CHK( mbedtls_mpi_safe_cond_assign( &M, &mm, ! m_is_odd ) );
-
-    /*
-     * Go for comb multiplication, R = M * P
-     */
-    ecp_comb_fixed( k, d, w, &M );
-    MBEDTLS_MPI_CHK( ecp_mul_comb_core( grp, R, T, pre_len, k, d, f_rng, p_rng ) );
-
-    /*
-     * Now get m * P from M * P and normalize it
-     */
-    MBEDTLS_MPI_CHK( ecp_safe_invert_jac( grp, R, ! m_is_odd ) );
-    MBEDTLS_MPI_CHK( ecp_normalize_jac( grp, R ) );
+    /* Actual comb multiplication using precomputed points */
+    MBEDTLS_MPI_CHK( ecp_mul_comb_after_precomp( grp, R, m,
+                                                 T, T_size, w, d,
+                                                 f_rng, p_rng, rs_ctx ) );
 
 cleanup:
 
-    if( T != NULL && ! p_eq_g )
+    /* does T belong to the group? */
+    if( T == grp->T )
+        T = NULL;
+
+    /* does T belong to the restart context? */
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    if( rs_ctx != NULL && rs_ctx->rsm != NULL && ret == MBEDTLS_ERR_ECP_IN_PROGRESS && T != NULL )
     {
-        for( i = 0; i < pre_len; i++ )
+        /* transfer ownership of T from local function to rsm */
+        rs_ctx->rsm->T_size = T_size;
+        rs_ctx->rsm->T = T;
+        T = NULL;
+    }
+#endif
+
+    /* did T belong to us? then let's destroy it! */
+    if( T != NULL )
+    {
+        for( i = 0; i < T_size; i++ )
             mbedtls_ecp_point_free( &T[i] );
         mbedtls_free( T );
     }
 
-    mbedtls_mpi_free( &M );
-    mbedtls_mpi_free( &mm );
-
+    /* don't free R while in progress in case R == P */
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    if( ret != MBEDTLS_ERR_ECP_IN_PROGRESS )
+#endif
+    /* prevent caller from using invalid value */
     if( ret != 0 )
         mbedtls_ecp_point_free( R );
 
+    ECP_RS_LEAVE( rsm );
+
     return( ret );
 }
 
@@ -1482,10 +2034,8 @@
     int ret;
 
 #if defined(MBEDTLS_ECP_NORMALIZE_MXZ_ALT)
-    if ( mbedtls_internal_ecp_grp_capable( grp ) )
-    {
-        return mbedtls_internal_ecp_normalize_mxz( grp, P );
-    }
+    if( mbedtls_internal_ecp_grp_capable( grp ) )
+        return( mbedtls_internal_ecp_normalize_mxz( grp, P ) );
 #endif /* MBEDTLS_ECP_NORMALIZE_MXZ_ALT */
 
     MBEDTLS_MPI_CHK( mbedtls_mpi_inv_mod( &P->Z, &P->Z, &grp->P ) );
@@ -1513,10 +2063,8 @@
     int count = 0;
 
 #if defined(MBEDTLS_ECP_RANDOMIZE_MXZ_ALT)
-    if ( mbedtls_internal_ecp_grp_capable( grp ) )
-    {
-        return mbedtls_internal_ecp_randomize_mxz( grp, P, f_rng, p_rng );
-    }
+    if( mbedtls_internal_ecp_grp_capable( grp ) )
+        return( mbedtls_internal_ecp_randomize_mxz( grp, P, f_rng, p_rng );
 #endif /* MBEDTLS_ECP_RANDOMIZE_MXZ_ALT */
 
     p_size = ( grp->pbits + 7 ) / 8;
@@ -1568,10 +2116,8 @@
     mbedtls_mpi A, AA, B, BB, E, C, D, DA, CB;
 
 #if defined(MBEDTLS_ECP_DOUBLE_ADD_MXZ_ALT)
-    if ( mbedtls_internal_ecp_grp_capable( grp ) )
-    {
-        return mbedtls_internal_ecp_double_add_mxz( grp, R, S, P, Q, d );
-    }
+    if( mbedtls_internal_ecp_grp_capable( grp ) )
+        return( mbedtls_internal_ecp_double_add_mxz( grp, R, S, P, Q, d ) );
 #endif /* MBEDTLS_ECP_DOUBLE_ADD_MXZ_ALT */
 
     mbedtls_mpi_init( &A ); mbedtls_mpi_init( &AA ); mbedtls_mpi_init( &B );
@@ -1668,54 +2214,77 @@
 #endif /* ECP_MONTGOMERY */
 
 /*
- * Multiplication R = m * P
+ * Restartable multiplication R = m * P
  */
-int mbedtls_ecp_mul( mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
+int mbedtls_ecp_mul_restartable( mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
              const mbedtls_mpi *m, const mbedtls_ecp_point *P,
-             int (*f_rng)(void *, unsigned char *, size_t), void *p_rng )
+             int (*f_rng)(void *, unsigned char *, size_t), void *p_rng,
+             mbedtls_ecp_restart_ctx *rs_ctx )
 {
     int ret = MBEDTLS_ERR_ECP_BAD_INPUT_DATA;
 #if defined(MBEDTLS_ECP_INTERNAL_ALT)
     char is_grp_capable = 0;
 #endif
 
-    /* Common sanity checks */
-    if( mbedtls_mpi_cmp_int( &P->Z, 1 ) != 0 )
-        return( MBEDTLS_ERR_ECP_BAD_INPUT_DATA );
-
-    if( ( ret = mbedtls_ecp_check_privkey( grp, m ) ) != 0 ||
-        ( ret = mbedtls_ecp_check_pubkey( grp, P ) ) != 0 )
-        return( ret );
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    /* reset ops count for this call if top-level */
+    if( rs_ctx != NULL && rs_ctx->depth++ == 0 )
+        rs_ctx->ops_done = 0;
+#endif
 
 #if defined(MBEDTLS_ECP_INTERNAL_ALT)
-    if ( is_grp_capable = mbedtls_internal_ecp_grp_capable( grp )  )
-    {
+    if( ( is_grp_capable = mbedtls_internal_ecp_grp_capable( grp ) ) )
         MBEDTLS_MPI_CHK( mbedtls_internal_ecp_init( grp ) );
+#endif /* MBEDTLS_ECP_INTERNAL_ALT */
+
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    /* skip argument check when restarting */
+    if( rs_ctx == NULL || rs_ctx->rsm == NULL )
+#endif
+    {
+        /* check_privkey is free */
+        MBEDTLS_ECP_BUDGET( MBEDTLS_ECP_OPS_CHK );
+
+        /* Common sanity checks */
+        MBEDTLS_MPI_CHK( mbedtls_ecp_check_privkey( grp, m ) );
+        MBEDTLS_MPI_CHK( mbedtls_ecp_check_pubkey( grp, P ) );
     }
 
-#endif /* MBEDTLS_ECP_INTERNAL_ALT */
+    ret = MBEDTLS_ERR_ECP_BAD_INPUT_DATA;
 #if defined(ECP_MONTGOMERY)
     if( ecp_get_type( grp ) == ECP_TYPE_MONTGOMERY )
-        ret = ecp_mul_mxz( grp, R, m, P, f_rng, p_rng );
-
+        MBEDTLS_MPI_CHK( ecp_mul_mxz( grp, R, m, P, f_rng, p_rng ) );
 #endif
 #if defined(ECP_SHORTWEIERSTRASS)
     if( ecp_get_type( grp ) == ECP_TYPE_SHORT_WEIERSTRASS )
-        ret = ecp_mul_comb( grp, R, m, P, f_rng, p_rng );
-
+        MBEDTLS_MPI_CHK( ecp_mul_comb( grp, R, m, P, f_rng, p_rng, rs_ctx ) );
 #endif
-#if defined(MBEDTLS_ECP_INTERNAL_ALT)
+
 cleanup:
 
-    if ( is_grp_capable )
-    {
+#if defined(MBEDTLS_ECP_INTERNAL_ALT)
+    if( is_grp_capable )
         mbedtls_internal_ecp_free( grp );
-    }
-
 #endif /* MBEDTLS_ECP_INTERNAL_ALT */
+
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    if( rs_ctx != NULL )
+        rs_ctx->depth--;
+#endif
+
     return( ret );
 }
 
+/*
+ * Multiplication R = m * P
+ */
+int mbedtls_ecp_mul( mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
+             const mbedtls_mpi *m, const mbedtls_ecp_point *P,
+             int (*f_rng)(void *, unsigned char *, size_t), void *p_rng )
+{
+    return( mbedtls_ecp_mul_restartable( grp, R, m, P, f_rng, p_rng, NULL ) );
+}
+
 #if defined(ECP_SHORTWEIERSTRASS)
 /*
  * Check that an affine point is valid as a public key,
@@ -1773,7 +2342,8 @@
 static int mbedtls_ecp_mul_shortcuts( mbedtls_ecp_group *grp,
                                       mbedtls_ecp_point *R,
                                       const mbedtls_mpi *m,
-                                      const mbedtls_ecp_point *P )
+                                      const mbedtls_ecp_point *P,
+                                      mbedtls_ecp_restart_ctx *rs_ctx )
 {
     int ret;
 
@@ -1789,7 +2359,8 @@
     }
     else
     {
-        MBEDTLS_MPI_CHK( mbedtls_ecp_mul( grp, R, m, P, NULL, NULL ) );
+        MBEDTLS_MPI_CHK( mbedtls_ecp_mul_restartable( grp, R, m, P,
+                                                      NULL, NULL, rs_ctx ) );
     }
 
 cleanup:
@@ -1797,6 +2368,96 @@
 }
 
 /*
+ * Restartable linear combination
+ * NOT constant-time
+ */
+int mbedtls_ecp_muladd_restartable(
+             mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
+             const mbedtls_mpi *m, const mbedtls_ecp_point *P,
+             const mbedtls_mpi *n, const mbedtls_ecp_point *Q,
+             mbedtls_ecp_restart_ctx *rs_ctx )
+{
+    int ret;
+    mbedtls_ecp_point mP;
+    mbedtls_ecp_point *pmP = &mP;
+    mbedtls_ecp_point *pR = R;
+#if defined(MBEDTLS_ECP_INTERNAL_ALT)
+    char is_grp_capable = 0;
+#endif
+
+    if( ecp_get_type( grp ) != ECP_TYPE_SHORT_WEIERSTRASS )
+        return( MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE );
+
+    mbedtls_ecp_point_init( &mP );
+
+#if defined(MBEDTLS_ECP_INTERNAL_ALT)
+    if( ( is_grp_capable = mbedtls_internal_ecp_grp_capable( grp ) ) )
+        MBEDTLS_MPI_CHK( mbedtls_internal_ecp_init( grp ) );
+#endif /* MBEDTLS_ECP_INTERNAL_ALT */
+
+    ECP_RS_ENTER( ma );
+
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    if( rs_ctx != NULL && rs_ctx->ma != NULL )
+    {
+        /* redirect intermediate results to restart context */
+        pmP = &rs_ctx->ma->mP;
+        pR  = &rs_ctx->ma->R;
+
+        /* jump to next operation */
+        if( rs_ctx->ma->state == ecp_rsma_mul2 )
+            goto mul2;
+        if( rs_ctx->ma->state == ecp_rsma_add )
+            goto add;
+        if( rs_ctx->ma->state == ecp_rsma_norm )
+            goto norm;
+    }
+#endif /* MBEDTLS_ECP_RESTARTABLE */
+
+    MBEDTLS_MPI_CHK( mbedtls_ecp_mul_shortcuts( grp, pmP, m, P, rs_ctx ) );
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    if( rs_ctx != NULL && rs_ctx->ma != NULL )
+        rs_ctx->ma->state = ecp_rsma_mul2;
+
+mul2:
+#endif
+    MBEDTLS_MPI_CHK( mbedtls_ecp_mul_shortcuts( grp, pR,  n, Q, rs_ctx ) );
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    if( rs_ctx != NULL && rs_ctx->ma != NULL )
+        rs_ctx->ma->state = ecp_rsma_add;
+
+add:
+#endif
+    MBEDTLS_ECP_BUDGET( MBEDTLS_ECP_OPS_ADD );
+    MBEDTLS_MPI_CHK( ecp_add_mixed( grp, pR, pmP, pR ) );
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    if( rs_ctx != NULL && rs_ctx->ma != NULL )
+        rs_ctx->ma->state = ecp_rsma_norm;
+
+norm:
+#endif
+    MBEDTLS_ECP_BUDGET( MBEDTLS_ECP_OPS_INV );
+    MBEDTLS_MPI_CHK( ecp_normalize_jac( grp, pR ) );
+
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    if( rs_ctx != NULL && rs_ctx->ma != NULL )
+        MBEDTLS_MPI_CHK( mbedtls_ecp_copy( R, pR ) );
+#endif
+
+cleanup:
+#if defined(MBEDTLS_ECP_INTERNAL_ALT)
+    if( is_grp_capable )
+        mbedtls_internal_ecp_free( grp );
+#endif /* MBEDTLS_ECP_INTERNAL_ALT */
+
+    mbedtls_ecp_point_free( &mP );
+
+    ECP_RS_LEAVE( ma );
+
+    return( ret );
+}
+
+/*
  * Linear combination
  * NOT constant-time
  */
@@ -1804,45 +2465,9 @@
              const mbedtls_mpi *m, const mbedtls_ecp_point *P,
              const mbedtls_mpi *n, const mbedtls_ecp_point *Q )
 {
-    int ret;
-    mbedtls_ecp_point mP;
-#if defined(MBEDTLS_ECP_INTERNAL_ALT)
-    char is_grp_capable = 0;
-#endif
-
-    if( ecp_get_type( grp ) != ECP_TYPE_SHORT_WEIERSTRASS )
-        return( MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE );
-
-    mbedtls_ecp_point_init( &mP );
-
-    MBEDTLS_MPI_CHK( mbedtls_ecp_mul_shortcuts( grp, &mP, m, P ) );
-    MBEDTLS_MPI_CHK( mbedtls_ecp_mul_shortcuts( grp, R,   n, Q ) );
-
-#if defined(MBEDTLS_ECP_INTERNAL_ALT)
-    if (  is_grp_capable = mbedtls_internal_ecp_grp_capable( grp )  )
-    {
-        MBEDTLS_MPI_CHK( mbedtls_internal_ecp_init( grp ) );
-    }
-
-#endif /* MBEDTLS_ECP_INTERNAL_ALT */
-    MBEDTLS_MPI_CHK( ecp_add_mixed( grp, R, &mP, R ) );
-    MBEDTLS_MPI_CHK( ecp_normalize_jac( grp, R ) );
-
-cleanup:
-
-#if defined(MBEDTLS_ECP_INTERNAL_ALT)
-    if ( is_grp_capable )
-    {
-        mbedtls_internal_ecp_free( grp );
-    }
-
-#endif /* MBEDTLS_ECP_INTERNAL_ALT */
-    mbedtls_ecp_point_free( &mP );
-
-    return( ret );
+    return( mbedtls_ecp_muladd_restartable( grp, R, m, P, n, Q, NULL ) );
 }
 
-
 #if defined(ECP_MONTGOMERY)
 /*
  * Check validity of a public key for Montgomery curves with x-only schemes
@@ -1917,15 +2542,14 @@
 }
 
 /*
- * Generate a keypair with configurable base point
+ * Generate a private key
  */
-int mbedtls_ecp_gen_keypair_base( mbedtls_ecp_group *grp,
-                     const mbedtls_ecp_point *G,
-                     mbedtls_mpi *d, mbedtls_ecp_point *Q,
+int mbedtls_ecp_gen_privkey( const mbedtls_ecp_group *grp,
+                     mbedtls_mpi *d,
                      int (*f_rng)(void *, unsigned char *, size_t),
                      void *p_rng )
 {
-    int ret;
+    int ret = MBEDTLS_ERR_ECP_BAD_INPUT_DATA;
     size_t n_size = ( grp->nbits + 7 ) / 8;
 
 #if defined(ECP_MONTGOMERY)
@@ -1954,8 +2578,8 @@
             MBEDTLS_MPI_CHK( mbedtls_mpi_set_bit( d, 2, 0 ) );
         }
     }
-    else
 #endif /* ECP_MONTGOMERY */
+
 #if defined(ECP_SHORTWEIERSTRASS)
     if( ecp_get_type( grp ) == ECP_TYPE_SHORT_WEIERSTRASS )
     {
@@ -1989,15 +2613,28 @@
         while( mbedtls_mpi_cmp_int( d, 1 ) < 0 ||
                mbedtls_mpi_cmp_mpi( d, &grp->N ) >= 0 );
     }
-    else
 #endif /* ECP_SHORTWEIERSTRASS */
-        return( MBEDTLS_ERR_ECP_BAD_INPUT_DATA );
 
 cleanup:
-    if( ret != 0 )
-        return( ret );
+    return( ret );
+}
 
-    return( mbedtls_ecp_mul( grp, Q, d, G, f_rng, p_rng ) );
+/*
+ * Generate a keypair with configurable base point
+ */
+int mbedtls_ecp_gen_keypair_base( mbedtls_ecp_group *grp,
+                     const mbedtls_ecp_point *G,
+                     mbedtls_mpi *d, mbedtls_ecp_point *Q,
+                     int (*f_rng)(void *, unsigned char *, size_t),
+                     void *p_rng )
+{
+    int ret;
+
+    MBEDTLS_MPI_CHK( mbedtls_ecp_gen_privkey( grp, d, f_rng, p_rng ) );
+    MBEDTLS_MPI_CHK( mbedtls_ecp_mul( grp, Q, d, G, f_rng, p_rng ) );
+
+cleanup:
+    return( ret );
 }
 
 /*
diff --git a/library/error.c b/library/error.c
index 8818054..a2de275 100644
--- a/library/error.c
+++ b/library/error.c
@@ -273,6 +273,8 @@
             mbedtls_snprintf( buf, buflen, "ECP - The buffer contains a valid signature followed by more data" );
         if( use_ret == -(MBEDTLS_ERR_ECP_HW_ACCEL_FAILED) )
             mbedtls_snprintf( buf, buflen, "ECP - The ECP hardware accelerator failed" );
+        if( use_ret == -(MBEDTLS_ERR_ECP_IN_PROGRESS) )
+            mbedtls_snprintf( buf, buflen, "ECP - Operation in progress, try again with the same parameters" );
 #endif /* MBEDTLS_ECP_C */
 
 #if defined(MBEDTLS_MD_C)
diff --git a/library/pk.c b/library/pk.c
index f05b139..c793fd8 100644
--- a/library/pk.c
+++ b/library/pk.c
@@ -69,6 +69,34 @@
     mbedtls_platform_zeroize( ctx, sizeof( mbedtls_pk_context ) );
 }
 
+#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
+/*
+ * Initialize a restart context
+ */
+void mbedtls_pk_restart_init( mbedtls_pk_restart_ctx *ctx )
+{
+    ctx->pk_info = NULL;
+    ctx->rs_ctx = NULL;
+}
+
+/*
+ * Free the components of a restart context
+ */
+void mbedtls_pk_restart_free( mbedtls_pk_restart_ctx *ctx )
+{
+    if( ctx == NULL || ctx->pk_info == NULL ||
+        ctx->pk_info->rs_free_func == NULL )
+    {
+        return;
+    }
+
+    ctx->pk_info->rs_free_func( ctx->rs_ctx );
+
+    ctx->pk_info = NULL;
+    ctx->rs_ctx = NULL;
+}
+#endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
+
 /*
  * Get pk_info structure from type
  */
@@ -171,6 +199,73 @@
     return( 0 );
 }
 
+#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
+/*
+ * Helper to set up a restart context if needed
+ */
+static int pk_restart_setup( mbedtls_pk_restart_ctx *ctx,
+                               const mbedtls_pk_info_t *info )
+{
+    /* Don't do anything it already set up */
+    if( ctx->pk_info != NULL )
+        return( 0 );
+
+    /* Should never happen when we're called */
+    if( info->rs_alloc_func == NULL || info->rs_free_func == NULL )
+        return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
+
+    if( ( ctx->rs_ctx = info->rs_alloc_func() ) == NULL )
+        return( MBEDTLS_ERR_PK_ALLOC_FAILED );
+
+    ctx->pk_info = info;
+
+    return( 0 );
+}
+#endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
+
+/*
+ * Verify a signature (restartable)
+ */
+int mbedtls_pk_verify_restartable( mbedtls_pk_context *ctx,
+               mbedtls_md_type_t md_alg,
+               const unsigned char *hash, size_t hash_len,
+               const unsigned char *sig, size_t sig_len,
+               mbedtls_pk_restart_ctx *rs_ctx )
+{
+    if( ctx == NULL || ctx->pk_info == NULL ||
+        pk_hashlen_helper( md_alg, &hash_len ) != 0 )
+        return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
+
+#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
+    /* optimization: use non-restartable version if restart disabled */
+    if( rs_ctx != NULL &&
+        mbedtls_ecp_restart_enabled() &&
+        ctx->pk_info->verify_rs_func != NULL )
+    {
+        int ret;
+
+        if( ( ret = pk_restart_setup( rs_ctx, ctx->pk_info ) ) != 0 )
+            return( ret );
+
+        ret = ctx->pk_info->verify_rs_func( ctx->pk_ctx,
+                   md_alg, hash, hash_len, sig, sig_len, rs_ctx->rs_ctx );
+
+        if( ret != MBEDTLS_ERR_ECP_IN_PROGRESS )
+            mbedtls_pk_restart_free( rs_ctx );
+
+        return( ret );
+    }
+#else /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
+    (void) rs_ctx;
+#endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
+
+    if( ctx->pk_info->verify_func == NULL )
+        return( MBEDTLS_ERR_PK_TYPE_MISMATCH );
+
+    return( ctx->pk_info->verify_func( ctx->pk_ctx, md_alg, hash, hash_len,
+                                       sig, sig_len ) );
+}
+
 /*
  * Verify a signature
  */
@@ -178,15 +273,8 @@
                const unsigned char *hash, size_t hash_len,
                const unsigned char *sig, size_t sig_len )
 {
-    if( ctx == NULL || ctx->pk_info == NULL ||
-        pk_hashlen_helper( md_alg, &hash_len ) != 0 )
-        return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
-
-    if( ctx->pk_info->verify_func == NULL )
-        return( MBEDTLS_ERR_PK_TYPE_MISMATCH );
-
-    return( ctx->pk_info->verify_func( ctx->pk_ctx, md_alg, hash, hash_len,
-                                       sig, sig_len ) );
+    return( mbedtls_pk_verify_restartable( ctx, md_alg, hash, hash_len,
+                                           sig, sig_len, NULL ) );
 }
 
 /*
@@ -248,6 +336,50 @@
 }
 
 /*
+ * Make a signature (restartable)
+ */
+int mbedtls_pk_sign_restartable( mbedtls_pk_context *ctx,
+             mbedtls_md_type_t md_alg,
+             const unsigned char *hash, size_t hash_len,
+             unsigned char *sig, size_t *sig_len,
+             int (*f_rng)(void *, unsigned char *, size_t), void *p_rng,
+             mbedtls_pk_restart_ctx *rs_ctx )
+{
+    if( ctx == NULL || ctx->pk_info == NULL ||
+        pk_hashlen_helper( md_alg, &hash_len ) != 0 )
+        return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
+
+#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
+    /* optimization: use non-restartable version if restart disabled */
+    if( rs_ctx != NULL &&
+        mbedtls_ecp_restart_enabled() &&
+        ctx->pk_info->sign_rs_func != NULL )
+    {
+        int ret;
+
+        if( ( ret = pk_restart_setup( rs_ctx, ctx->pk_info ) ) != 0 )
+            return( ret );
+
+        ret = ctx->pk_info->sign_rs_func( ctx->pk_ctx, md_alg,
+                hash, hash_len, sig, sig_len, f_rng, p_rng, rs_ctx->rs_ctx );
+
+        if( ret != MBEDTLS_ERR_ECP_IN_PROGRESS )
+            mbedtls_pk_restart_free( rs_ctx );
+
+        return( ret );
+    }
+#else /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
+    (void) rs_ctx;
+#endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
+
+    if( ctx->pk_info->sign_func == NULL )
+        return( MBEDTLS_ERR_PK_TYPE_MISMATCH );
+
+    return( ctx->pk_info->sign_func( ctx->pk_ctx, md_alg, hash, hash_len,
+                                     sig, sig_len, f_rng, p_rng ) );
+}
+
+/*
  * Make a signature
  */
 int mbedtls_pk_sign( mbedtls_pk_context *ctx, mbedtls_md_type_t md_alg,
@@ -255,15 +387,8 @@
              unsigned char *sig, size_t *sig_len,
              int (*f_rng)(void *, unsigned char *, size_t), void *p_rng )
 {
-    if( ctx == NULL || ctx->pk_info == NULL ||
-        pk_hashlen_helper( md_alg, &hash_len ) != 0 )
-        return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
-
-    if( ctx->pk_info->sign_func == NULL )
-        return( MBEDTLS_ERR_PK_TYPE_MISMATCH );
-
-    return( ctx->pk_info->sign_func( ctx->pk_ctx, md_alg, hash, hash_len,
-                                     sig, sig_len, f_rng, p_rng ) );
+    return( mbedtls_pk_sign_restartable( ctx, md_alg, hash, hash_len,
+                                         sig, sig_len, f_rng, p_rng, NULL ) );
 }
 
 /*
diff --git a/library/pk_wrap.c b/library/pk_wrap.c
index 2c7d2d7..cb08eba 100644
--- a/library/pk_wrap.c
+++ b/library/pk_wrap.c
@@ -190,11 +190,19 @@
     rsa_can_do,
     rsa_verify_wrap,
     rsa_sign_wrap,
+#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
+    NULL,
+    NULL,
+#endif
     rsa_decrypt_wrap,
     rsa_encrypt_wrap,
     rsa_check_pair_wrap,
     rsa_alloc_wrap,
     rsa_free_wrap,
+#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
+    NULL,
+    NULL,
+#endif
     rsa_debug,
 };
 #endif /* MBEDTLS_RSA_C */
@@ -262,6 +270,110 @@
     return( ret );
 }
 
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+/* Forward declarations */
+static int ecdsa_verify_rs_wrap( void *ctx, mbedtls_md_type_t md_alg,
+                       const unsigned char *hash, size_t hash_len,
+                       const unsigned char *sig, size_t sig_len,
+                       void *rs_ctx );
+
+static int ecdsa_sign_rs_wrap( void *ctx, mbedtls_md_type_t md_alg,
+                   const unsigned char *hash, size_t hash_len,
+                   unsigned char *sig, size_t *sig_len,
+                   int (*f_rng)(void *, unsigned char *, size_t), void *p_rng,
+                   void *rs_ctx );
+
+/*
+ * Restart context for ECDSA operations with ECKEY context
+ *
+ * We need to store an actual ECDSA context, as we need to pass the same to
+ * the underlying ecdsa function, so we can't create it on the fly every time.
+ */
+typedef struct
+{
+    mbedtls_ecdsa_restart_ctx ecdsa_rs;
+    mbedtls_ecdsa_context ecdsa_ctx;
+} eckey_restart_ctx;
+
+static void *eckey_rs_alloc( void )
+{
+    eckey_restart_ctx *rs_ctx;
+
+    void *ctx = mbedtls_calloc( 1, sizeof( eckey_restart_ctx ) );
+
+    if( ctx != NULL )
+    {
+        rs_ctx = ctx;
+        mbedtls_ecdsa_restart_init( &rs_ctx->ecdsa_rs );
+        mbedtls_ecdsa_init( &rs_ctx->ecdsa_ctx );
+    }
+
+    return( ctx );
+}
+
+static void eckey_rs_free( void *ctx )
+{
+    eckey_restart_ctx *rs_ctx;
+
+    if( ctx == NULL)
+        return;
+
+    rs_ctx = ctx;
+    mbedtls_ecdsa_restart_free( &rs_ctx->ecdsa_rs );
+    mbedtls_ecdsa_free( &rs_ctx->ecdsa_ctx );
+
+    mbedtls_free( ctx );
+}
+
+static int eckey_verify_rs_wrap( void *ctx, mbedtls_md_type_t md_alg,
+                       const unsigned char *hash, size_t hash_len,
+                       const unsigned char *sig, size_t sig_len,
+                       void *rs_ctx )
+{
+    int ret;
+    eckey_restart_ctx *rs = rs_ctx;
+
+    /* Should never happen */
+    if( rs == NULL )
+        return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
+
+    /* set up our own sub-context if needed */
+    if( rs->ecdsa_ctx.grp.pbits == 0 )
+        MBEDTLS_MPI_CHK( mbedtls_ecdsa_from_keypair( &rs->ecdsa_ctx, ctx ) );
+
+    MBEDTLS_MPI_CHK( ecdsa_verify_rs_wrap( &rs->ecdsa_ctx,
+                                           md_alg, hash, hash_len,
+                                           sig, sig_len, &rs->ecdsa_rs ) );
+
+cleanup:
+    return( ret );
+}
+
+static int eckey_sign_rs_wrap( void *ctx, mbedtls_md_type_t md_alg,
+                   const unsigned char *hash, size_t hash_len,
+                   unsigned char *sig, size_t *sig_len,
+                   int (*f_rng)(void *, unsigned char *, size_t), void *p_rng,
+                       void *rs_ctx )
+{
+    int ret;
+    eckey_restart_ctx *rs = rs_ctx;
+
+    /* Should never happen */
+    if( rs == NULL )
+        return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
+
+    /* set up our own sub-context if needed */
+    if( rs->ecdsa_ctx.grp.pbits == 0 )
+        MBEDTLS_MPI_CHK( mbedtls_ecdsa_from_keypair( &rs->ecdsa_ctx, ctx ) );
+
+    MBEDTLS_MPI_CHK( ecdsa_sign_rs_wrap( &rs->ecdsa_ctx, md_alg,
+                                         hash, hash_len, sig, sig_len,
+                                         f_rng, p_rng, &rs->ecdsa_rs ) );
+
+cleanup:
+    return( ret );
+}
+#endif /* MBEDTLS_ECP_RESTARTABLE */
 #endif /* MBEDTLS_ECDSA_C */
 
 static int eckey_check_pair( const void *pub, const void *prv )
@@ -301,15 +413,23 @@
 #if defined(MBEDTLS_ECDSA_C)
     eckey_verify_wrap,
     eckey_sign_wrap,
-#else
-    NULL,
-    NULL,
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    eckey_verify_rs_wrap,
+    eckey_sign_rs_wrap,
 #endif
+#else /* MBEDTLS_ECDSA_C */
+    NULL,
+    NULL,
+#endif /* MBEDTLS_ECDSA_C */
     NULL,
     NULL,
     eckey_check_pair,
     eckey_alloc_wrap,
     eckey_free_wrap,
+#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
+    eckey_rs_alloc,
+    eckey_rs_free,
+#endif
     eckey_debug,
 };
 
@@ -329,11 +449,19 @@
     eckeydh_can_do,
     NULL,
     NULL,
+#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
+    NULL,
+    NULL,
+#endif
     NULL,
     NULL,
     eckey_check_pair,
     eckey_alloc_wrap,       /* Same underlying key structure */
     eckey_free_wrap,        /* Same underlying key structure */
+#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
+    NULL,
+    NULL,
+#endif
     eckey_debug,            /* Same underlying key structure */
 };
 #endif /* MBEDTLS_ECP_C */
@@ -369,6 +497,40 @@
                 md_alg, hash, hash_len, sig, sig_len, f_rng, p_rng ) );
 }
 
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+static int ecdsa_verify_rs_wrap( void *ctx, mbedtls_md_type_t md_alg,
+                       const unsigned char *hash, size_t hash_len,
+                       const unsigned char *sig, size_t sig_len,
+                       void *rs_ctx )
+{
+    int ret;
+    ((void) md_alg);
+
+    ret = mbedtls_ecdsa_read_signature_restartable(
+            (mbedtls_ecdsa_context *) ctx,
+            hash, hash_len, sig, sig_len,
+            (mbedtls_ecdsa_restart_ctx *) rs_ctx );
+
+    if( ret == MBEDTLS_ERR_ECP_SIG_LEN_MISMATCH )
+        return( MBEDTLS_ERR_PK_SIG_LEN_MISMATCH );
+
+    return( ret );
+}
+
+static int ecdsa_sign_rs_wrap( void *ctx, mbedtls_md_type_t md_alg,
+                   const unsigned char *hash, size_t hash_len,
+                   unsigned char *sig, size_t *sig_len,
+                   int (*f_rng)(void *, unsigned char *, size_t), void *p_rng,
+                   void *rs_ctx )
+{
+    return( mbedtls_ecdsa_write_signature_restartable(
+                (mbedtls_ecdsa_context *) ctx,
+                md_alg, hash, hash_len, sig, sig_len, f_rng, p_rng,
+                (mbedtls_ecdsa_restart_ctx *) rs_ctx ) );
+
+}
+#endif /* MBEDTLS_ECP_RESTARTABLE */
+
 static void *ecdsa_alloc_wrap( void )
 {
     void *ctx = mbedtls_calloc( 1, sizeof( mbedtls_ecdsa_context ) );
@@ -385,6 +547,24 @@
     mbedtls_free( ctx );
 }
 
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+static void *ecdsa_rs_alloc( void )
+{
+    void *ctx = mbedtls_calloc( 1, sizeof( mbedtls_ecdsa_restart_ctx ) );
+
+    if( ctx != NULL )
+        mbedtls_ecdsa_restart_init( ctx );
+
+    return( ctx );
+}
+
+static void ecdsa_rs_free( void *ctx )
+{
+    mbedtls_ecdsa_restart_free( ctx );
+    mbedtls_free( ctx );
+}
+#endif /* MBEDTLS_ECP_RESTARTABLE */
+
 const mbedtls_pk_info_t mbedtls_ecdsa_info = {
     MBEDTLS_PK_ECDSA,
     "ECDSA",
@@ -392,11 +572,19 @@
     ecdsa_can_do,
     ecdsa_verify_wrap,
     ecdsa_sign_wrap,
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    ecdsa_verify_rs_wrap,
+    ecdsa_sign_rs_wrap,
+#endif
     NULL,
     NULL,
     eckey_check_pair,   /* Compatible key structures */
     ecdsa_alloc_wrap,
     ecdsa_free_wrap,
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    ecdsa_rs_alloc,
+    ecdsa_rs_free,
+#endif
     eckey_debug,        /* Compatible key structures */
 };
 #endif /* MBEDTLS_ECDSA_C */
@@ -506,6 +694,10 @@
     rsa_alt_can_do,
     NULL,
     rsa_alt_sign_wrap,
+#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
+    NULL,
+    NULL,
+#endif
     rsa_alt_decrypt_wrap,
     NULL,
 #if defined(MBEDTLS_RSA_C)
@@ -515,6 +707,10 @@
 #endif
     rsa_alt_alloc_wrap,
     rsa_alt_free_wrap,
+#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
+    NULL,
+    NULL,
+#endif
     NULL,
 };
 
diff --git a/library/ssl_cli.c b/library/ssl_cli.c
index 7455e99..7a6ffe0 100644
--- a/library/ssl_cli.c
+++ b/library/ssl_cli.c
@@ -1742,6 +1742,14 @@
 
     MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, chosen ciphersuite: %s", suite_info->name ) );
 
+#if defined(MBEDTLS_SSL__ECP_RESTARTABLE)
+    if( suite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA &&
+        ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_3 )
+    {
+        ssl->handshake->ecrs_enabled = 1;
+    }
+#endif
+
     if( comp != MBEDTLS_SSL_COMPRESS_NULL
 #if defined(MBEDTLS_ZLIB_SUPPORT)
         && comp != MBEDTLS_SSL_COMPRESS_DEFLATE
@@ -2328,6 +2336,14 @@
 #endif /* MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED ||
           MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED */
 
+#if defined(MBEDTLS_SSL__ECP_RESTARTABLE)
+    if( ssl->handshake->ecrs_enabled &&
+        ssl->handshake->ecrs_state == ssl_ecrs_ske_start_processing )
+    {
+        goto start_processing;
+    }
+#endif
+
     if( ( ret = mbedtls_ssl_read_record( ssl ) ) != 0 )
     {
         MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_read_record", ret );
@@ -2365,6 +2381,12 @@
         return( MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE );
     }
 
+#if defined(MBEDTLS_SSL__ECP_RESTARTABLE)
+    if( ssl->handshake->ecrs_enabled )
+        ssl->handshake->ecrs_state = ssl_ecrs_ske_start_processing;
+
+start_processing:
+#endif
     p   = ssl->in_msg + mbedtls_ssl_hs_hdr_len( ssl );
     end = ssl->in_msg + ssl->in_hslen;
     MBEDTLS_SSL_DEBUG_BUF( 3,   "server key exchange", p, end - p );
@@ -2457,6 +2479,7 @@
         mbedtls_pk_type_t pk_alg = MBEDTLS_PK_NONE;
         unsigned char *params = ssl->in_msg + mbedtls_ssl_hs_hdr_len( ssl );
         size_t params_len = p - params;
+        void *rs_ctx = NULL;
 
         /*
          * Handle the digitally-signed structure
@@ -2581,11 +2604,20 @@
             return( MBEDTLS_ERR_SSL_PK_TYPE_MISMATCH );
         }
 
-        if( ( ret = mbedtls_pk_verify( &ssl->session_negotiate->peer_cert->pk,
-                               md_alg, hash, hashlen, p, sig_len ) ) != 0 )
+#if defined(MBEDTLS_SSL__ECP_RESTARTABLE)
+        if( ssl->handshake->ecrs_enabled )
+            rs_ctx = &ssl->handshake->ecrs_ctx.pk;
+#endif
+
+        if( ( ret = mbedtls_pk_verify_restartable(
+                        &ssl->session_negotiate->peer_cert->pk,
+                        md_alg, hash, hashlen, p, sig_len, rs_ctx ) ) != 0 )
         {
-            mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
-                                            MBEDTLS_SSL_ALERT_MSG_DECRYPT_ERROR );
+#if defined(MBEDTLS_SSL__ECP_RESTARTABLE)
+            if( ret != MBEDTLS_ERR_ECP_IN_PROGRESS )
+#endif
+                mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
+                                                MBEDTLS_SSL_ALERT_MSG_DECRYPT_ERROR );
             MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_pk_verify", ret );
             return( ret );
         }
@@ -2884,6 +2916,16 @@
          */
         i = 4;
 
+#if defined(MBEDTLS_SSL__ECP_RESTARTABLE)
+        if( ssl->handshake->ecrs_enabled )
+        {
+            if( ssl->handshake->ecrs_state == ssl_ecrs_ske_ecdh_calc_secret )
+                goto ecdh_calc_secret;
+
+            mbedtls_ecdh_enable_restart( &ssl->handshake->ecdh_ctx );
+        }
+#endif
+
         ret = mbedtls_ecdh_make_public( &ssl->handshake->ecdh_ctx,
                                 &n,
                                 &ssl->out_msg[i], 1000,
@@ -2896,6 +2938,17 @@
 
         MBEDTLS_SSL_DEBUG_ECP( 3, "ECDH: Q", &ssl->handshake->ecdh_ctx.Q );
 
+#if defined(MBEDTLS_SSL__ECP_RESTARTABLE)
+        if( ssl->handshake->ecrs_enabled )
+        {
+            ssl->handshake->ecrs_n = n;
+            ssl->handshake->ecrs_state = ssl_ecrs_ske_ecdh_calc_secret;
+        }
+
+ecdh_calc_secret:
+        if( ssl->handshake->ecrs_enabled )
+            n = ssl->handshake->ecrs_n;
+#endif
         if( ( ret = mbedtls_ecdh_calc_secret( &ssl->handshake->ecdh_ctx,
                                       &ssl->handshake->pmslen,
                                        ssl->handshake->premaster,
@@ -3121,9 +3174,18 @@
     unsigned char *hash_start = hash;
     mbedtls_md_type_t md_alg = MBEDTLS_MD_NONE;
     unsigned int hashlen;
+    void *rs_ctx = NULL;
 
     MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> write certificate verify" ) );
 
+#if defined(MBEDTLS_SSL__ECP_RESTARTABLE)
+    if( ssl->handshake->ecrs_enabled &&
+        ssl->handshake->ecrs_state == ssl_ecrs_crt_vrfy_sign )
+    {
+        goto sign;
+    }
+#endif
+
     if( ( ret = mbedtls_ssl_derive_keys( ssl ) ) != 0 )
     {
         MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_derive_keys", ret );
@@ -3155,8 +3217,15 @@
     }
 
     /*
-     * Make an RSA signature of the handshake digests
+     * Make a signature of the handshake digests
      */
+#if defined(MBEDTLS_SSL__ECP_RESTARTABLE)
+    if( ssl->handshake->ecrs_enabled )
+        ssl->handshake->ecrs_state = ssl_ecrs_crt_vrfy_sign;
+
+sign:
+#endif
+
     ssl->handshake->calc_verify( ssl, hash );
 
 #if defined(MBEDTLS_SSL_PROTO_SSL3) || defined(MBEDTLS_SSL_PROTO_TLS1) || \
@@ -3233,9 +3302,15 @@
         return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
     }
 
-    if( ( ret = mbedtls_pk_sign( mbedtls_ssl_own_key( ssl ), md_alg, hash_start, hashlen,
+#if defined(MBEDTLS_SSL__ECP_RESTARTABLE)
+    if( ssl->handshake->ecrs_enabled )
+        rs_ctx = &ssl->handshake->ecrs_ctx.pk;
+#endif
+
+    if( ( ret = mbedtls_pk_sign_restartable( mbedtls_ssl_own_key( ssl ),
+                         md_alg, hash_start, hashlen,
                          ssl->out_msg + 6 + offset, &n,
-                         ssl->conf->f_rng, ssl->conf->p_rng ) ) != 0 )
+                         ssl->conf->f_rng, ssl->conf->p_rng, rs_ctx ) ) != 0 )
     {
         MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_pk_sign", ret );
         return( ret );
@@ -3249,7 +3324,6 @@
     ssl->out_msg[0]  = MBEDTLS_SSL_HS_CERTIFICATE_VERIFY;
 
     ssl->state++;
-
     if( ( ret = mbedtls_ssl_write_record( ssl ) ) != 0 )
     {
         MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_write_record", ret );
diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index e8e0cd8..8364eb8 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -4365,60 +4365,16 @@
     return( ret );
 }
 
-int mbedtls_ssl_parse_certificate( mbedtls_ssl_context *ssl )
+/*
+ * Once the certificate message is read, parse it into a cert chain and
+ * perform basic checks, but leave actual verification to the caller
+ */
+static int ssl_parse_certificate_chain( mbedtls_ssl_context *ssl )
 {
-    int ret = MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE;
+    int ret;
     size_t i, n;
-    const mbedtls_ssl_ciphersuite_t *ciphersuite_info = ssl->transform_negotiate->ciphersuite_info;
-    int authmode = ssl->conf->authmode;
     uint8_t alert;
 
-    MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> parse certificate" ) );
-
-    if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_PSK ||
-        ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_DHE_PSK ||
-        ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_PSK ||
-        ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECJPAKE )
-    {
-        MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip parse certificate" ) );
-        ssl->state++;
-        return( 0 );
-    }
-
-#if defined(MBEDTLS_SSL_SRV_C)
-    if( ssl->conf->endpoint == MBEDTLS_SSL_IS_SERVER &&
-        ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_RSA_PSK )
-    {
-        MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip parse certificate" ) );
-        ssl->state++;
-        return( 0 );
-    }
-
-#if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
-    if( ssl->handshake->sni_authmode != MBEDTLS_SSL_VERIFY_UNSET )
-        authmode = ssl->handshake->sni_authmode;
-#endif
-
-    if( ssl->conf->endpoint == MBEDTLS_SSL_IS_SERVER &&
-        authmode == MBEDTLS_SSL_VERIFY_NONE )
-    {
-        ssl->session_negotiate->verify_result = MBEDTLS_X509_BADCERT_SKIP_VERIFY;
-        MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip parse certificate" ) );
-        ssl->state++;
-        return( 0 );
-    }
-#endif
-
-    if( ( ret = mbedtls_ssl_read_record( ssl ) ) != 0 )
-    {
-        /* mbedtls_ssl_read_record may have sent an alert already. We
-           let it decide whether to alert. */
-        MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_read_record", ret );
-        return( ret );
-    }
-
-    ssl->state++;
-
 #if defined(MBEDTLS_SSL_SRV_C)
 #if defined(MBEDTLS_SSL_PROTO_SSL3)
     /*
@@ -4438,10 +4394,7 @@
                one. The client should know what's going on, so we
                don't send an alert. */
             ssl->session_negotiate->verify_result = MBEDTLS_X509_BADCERT_MISSING;
-            if( authmode == MBEDTLS_SSL_VERIFY_OPTIONAL )
-                return( 0 );
-            else
-                return( MBEDTLS_ERR_SSL_NO_CLIENT_CERTIFICATE );
+            return( MBEDTLS_ERR_SSL_NO_CLIENT_CERTIFICATE );
         }
     }
 #endif /* MBEDTLS_SSL_PROTO_SSL3 */
@@ -4462,10 +4415,7 @@
                one. The client should know what's going on, so we
                don't send an alert. */
             ssl->session_negotiate->verify_result = MBEDTLS_X509_BADCERT_MISSING;
-            if( authmode == MBEDTLS_SSL_VERIFY_OPTIONAL )
-                return( 0 );
-            else
-                return( MBEDTLS_ERR_SSL_NO_CLIENT_CERTIFICATE );
+            return( MBEDTLS_ERR_SSL_NO_CLIENT_CERTIFICATE );
         }
     }
 #endif /* MBEDTLS_SSL_PROTO_TLS1 || MBEDTLS_SSL_PROTO_TLS1_1 || \
@@ -4609,6 +4559,94 @@
     }
 #endif /* MBEDTLS_SSL_RENEGOTIATION && MBEDTLS_SSL_CLI_C */
 
+    return( 0 );
+}
+
+int mbedtls_ssl_parse_certificate( mbedtls_ssl_context *ssl )
+{
+    int ret;
+    const mbedtls_ssl_ciphersuite_t * const ciphersuite_info =
+          ssl->transform_negotiate->ciphersuite_info;
+#if defined(MBEDTLS_SSL_SRV_C) && defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
+    const int authmode = ssl->handshake->sni_authmode != MBEDTLS_SSL_VERIFY_UNSET
+                       ? ssl->handshake->sni_authmode
+                       : ssl->conf->authmode;
+#else
+    const int authmode = ssl->conf->authmode;
+#endif
+    void *rs_ctx = NULL;
+
+    MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> parse certificate" ) );
+
+    if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_PSK ||
+        ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_DHE_PSK ||
+        ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_PSK ||
+        ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECJPAKE )
+    {
+        MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip parse certificate" ) );
+        ssl->state++;
+        return( 0 );
+    }
+
+#if defined(MBEDTLS_SSL_SRV_C)
+    if( ssl->conf->endpoint == MBEDTLS_SSL_IS_SERVER &&
+        ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_RSA_PSK )
+    {
+        MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip parse certificate" ) );
+        ssl->state++;
+        return( 0 );
+    }
+
+    if( ssl->conf->endpoint == MBEDTLS_SSL_IS_SERVER &&
+        authmode == MBEDTLS_SSL_VERIFY_NONE )
+    {
+        ssl->session_negotiate->verify_result = MBEDTLS_X509_BADCERT_SKIP_VERIFY;
+        MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip parse certificate" ) );
+
+        ssl->state++;
+        return( 0 );
+    }
+#endif
+
+#if defined(MBEDTLS_SSL__ECP_RESTARTABLE)
+    if( ssl->handshake->ecrs_enabled &&
+        ssl->handshake->ecrs_state == ssl_ecrs_crt_verify )
+    {
+        goto crt_verify;
+    }
+#endif
+
+    if( ( ret = mbedtls_ssl_read_record( ssl ) ) != 0 )
+    {
+        /* mbedtls_ssl_read_record may have sent an alert already. We
+           let it decide whether to alert. */
+        MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_read_record", ret );
+        return( ret );
+    }
+
+    if( ( ret = ssl_parse_certificate_chain( ssl ) ) != 0 )
+    {
+#if defined(MBEDTLS_SSL_SRV_C)
+        if( ret == MBEDTLS_ERR_SSL_NO_CLIENT_CERTIFICATE &&
+            authmode == MBEDTLS_SSL_VERIFY_OPTIONAL )
+        {
+            ret = 0;
+        }
+#endif
+
+        ssl->state++;
+        return( ret );
+    }
+
+#if defined(MBEDTLS_SSL__ECP_RESTARTABLE)
+    if( ssl->handshake->ecrs_enabled)
+        ssl->handshake->ecrs_state = ssl_ecrs_crt_verify;
+
+crt_verify:
+    if( ssl->handshake->ecrs_enabled)
+        rs_ctx = &ssl->handshake->ecrs_ctx;
+#endif
+
     if( authmode != MBEDTLS_SSL_VERIFY_NONE )
     {
         mbedtls_x509_crt *ca_chain;
@@ -4630,19 +4668,24 @@
         /*
          * Main check: verify certificate
          */
-        ret = mbedtls_x509_crt_verify_with_profile(
+        ret = mbedtls_x509_crt_verify_restartable(
                                 ssl->session_negotiate->peer_cert,
                                 ca_chain, ca_crl,
                                 ssl->conf->cert_profile,
                                 ssl->hostname,
                                &ssl->session_negotiate->verify_result,
-                                ssl->conf->f_vrfy, ssl->conf->p_vrfy );
+                                ssl->conf->f_vrfy, ssl->conf->p_vrfy, rs_ctx );
 
         if( ret != 0 )
         {
             MBEDTLS_SSL_DEBUG_RET( 1, "x509_verify_cert", ret );
         }
 
+#if defined(MBEDTLS_SSL__ECP_RESTARTABLE)
+        if( ret == MBEDTLS_ERR_ECP_IN_PROGRESS )
+            return( ret );
+#endif
+
         /*
          * Secondary checks: always done, but change 'ret' only if it was 0
          */
@@ -4695,6 +4738,8 @@
 
         if( ret != 0 )
         {
+            uint8_t alert;
+
             /* The certificate may have been rejected for several reasons.
                Pick one and send the corresponding alert. Which alert to send
                may be a subject of debate in some cases. */
@@ -4737,6 +4782,8 @@
 #endif /* MBEDTLS_DEBUG_C */
     }
 
+    ssl->state++;
+
     MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= parse certificate" ) );
 
     return( ret );
@@ -5528,6 +5575,10 @@
 #endif
 #endif
 
+#if defined(MBEDTLS_SSL__ECP_RESTARTABLE)
+    mbedtls_x509_crt_restart_init( &handshake->ecrs_ctx );
+#endif
+
 #if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
     handshake->sni_authmode = MBEDTLS_SSL_VERIFY_UNSET;
 #endif
@@ -7454,6 +7505,10 @@
     }
 #endif /* MBEDTLS_X509_CRT_PARSE_C && MBEDTLS_SSL_SERVER_NAME_INDICATION */
 
+#if defined(MBEDTLS_SSL__ECP_RESTARTABLE)
+    mbedtls_x509_crt_restart_free( &handshake->ecrs_ctx );
+#endif
+
 #if defined(MBEDTLS_SSL_PROTO_DTLS)
     mbedtls_free( handshake->verify_cookie );
     mbedtls_free( handshake->hs_msg );
diff --git a/library/version_features.c b/library/version_features.c
index e8e448f..02a4643 100644
--- a/library/version_features.c
+++ b/library/version_features.c
@@ -318,6 +318,9 @@
 #if defined(MBEDTLS_ECP_NIST_OPTIM)
     "MBEDTLS_ECP_NIST_OPTIM",
 #endif /* MBEDTLS_ECP_NIST_OPTIM */
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    "MBEDTLS_ECP_RESTARTABLE",
+#endif /* MBEDTLS_ECP_RESTARTABLE */
 #if defined(MBEDTLS_ECDSA_DETERMINISTIC)
     "MBEDTLS_ECDSA_DETERMINISTIC",
 #endif /* MBEDTLS_ECDSA_DETERMINISTIC */
diff --git a/library/x509_crt.c b/library/x509_crt.c
index 290c1eb..4022cee 100644
--- a/library/x509_crt.c
+++ b/library/x509_crt.c
@@ -219,6 +219,23 @@
 }
 
 /*
+ * Reset (init or clear) a verify_chain
+ */
+static void x509_crt_verify_chain_reset(
+    mbedtls_x509_crt_verify_chain *ver_chain )
+{
+    size_t i;
+
+    for( i = 0; i < MBEDTLS_X509_MAX_VERIFY_CHAIN_SIZE; i++ )
+    {
+        ver_chain->items[i].crt = NULL;
+        ver_chain->items[i].flags = -1;
+    }
+
+    ver_chain->len = 0;
+}
+
+/*
  *  Version  ::=  INTEGER  {  v1(0), v2(1), v3(2)  }
  */
 static int x509_get_version( unsigned char **p,
@@ -1868,7 +1885,8 @@
  * Check the signature of a certificate by its parent
  */
 static int x509_crt_check_signature( const mbedtls_x509_crt *child,
-                                     mbedtls_x509_crt *parent )
+                                     mbedtls_x509_crt *parent,
+                                     mbedtls_x509_crt_restart_ctx *rs_ctx )
 {
     const mbedtls_md_info_t *md_info;
     unsigned char hash[MBEDTLS_MD_MAX_SIZE];
@@ -1880,14 +1898,24 @@
         return( -1 );
     }
 
-    if( mbedtls_pk_verify_ext( child->sig_pk, child->sig_opts, &parent->pk,
-                child->sig_md, hash, mbedtls_md_get_size( md_info ),
-                child->sig.p, child->sig.len ) != 0 )
-    {
+    /* Skip expensive computation on obvious mismatch */
+    if( ! mbedtls_pk_can_do( &parent->pk, child->sig_pk ) )
         return( -1 );
-    }
 
-    return( 0 );
+#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
+    if( rs_ctx != NULL && child->sig_pk == MBEDTLS_PK_ECDSA )
+    {
+        return( mbedtls_pk_verify_restartable( &parent->pk,
+                    child->sig_md, hash, mbedtls_md_get_size( md_info ),
+                    child->sig.p, child->sig.len, &rs_ctx->pk ) );
+    }
+#else
+    (void) rs_ctx;
+#endif
+
+    return( mbedtls_pk_verify_ext( child->sig_pk, child->sig_opts, &parent->pk,
+                child->sig_md, hash, mbedtls_md_get_size( md_info ),
+                child->sig.p, child->sig.len ) );
 }
 
 /*
@@ -1934,6 +1962,7 @@
  *  1. subject name matches child's issuer
  *  2. if necessary, the CA bit is set and key usage allows signing certs
  *  3. for trusted roots, the signature is correct
+ *     (for intermediates, the signature is checked and the result reported)
  *  4. pathlen constraints are satisfied
  *
  * If there's a suitable candidate which is also time-valid, return the first
@@ -1956,23 +1985,54 @@
  * Arguments:
  *  - [in] child: certificate for which we're looking for a parent
  *  - [in] candidates: chained list of potential parents
+ *  - [out] r_parent: parent found (or NULL)
+ *  - [out] r_signature_is_good: 1 if child signature by parent is valid, or 0
  *  - [in] top: 1 if candidates consists of trusted roots, ie we're at the top
  *         of the chain, 0 otherwise
  *  - [in] path_cnt: number of intermediates seen so far
  *  - [in] self_cnt: number of self-signed intermediates seen so far
  *         (will never be greater than path_cnt)
+ *  - [in-out] rs_ctx: context for restarting operations
  *
  * Return value:
- *  - the first suitable parent found (see above regarding time-validity)
- *  - NULL if no suitable parent was found
+ *  - 0 on success
+ *  - MBEDTLS_ERR_ECP_IN_PROGRESS otherwise
  */
-static mbedtls_x509_crt *x509_crt_find_parent_in( mbedtls_x509_crt *child,
-                                                  mbedtls_x509_crt *candidates,
-                                                  int top,
-                                                  size_t path_cnt,
-                                                  size_t self_cnt )
+static int x509_crt_find_parent_in(
+                        mbedtls_x509_crt *child,
+                        mbedtls_x509_crt *candidates,
+                        mbedtls_x509_crt **r_parent,
+                        int *r_signature_is_good,
+                        int top,
+                        unsigned path_cnt,
+                        unsigned self_cnt,
+                        mbedtls_x509_crt_restart_ctx *rs_ctx )
 {
-    mbedtls_x509_crt *parent, *badtime_parent = NULL;
+    int ret;
+    mbedtls_x509_crt *parent, *fallback_parent;
+    int signature_is_good, fallback_sign_good;
+
+#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
+    /* did we have something in progress? */
+    if( rs_ctx != NULL && rs_ctx->parent != NULL )
+    {
+        /* restore saved state */
+        parent = rs_ctx->parent;
+        fallback_parent = rs_ctx->fallback_parent;
+        fallback_sign_good = rs_ctx->fallback_sign_good;
+
+        /* clear saved state */
+        rs_ctx->parent = NULL;
+        rs_ctx->fallback_parent = NULL;
+        rs_ctx->fallback_sign_good = 0;
+
+        /* resume where we left */
+        goto check_signature;
+    }
+#endif
+
+    fallback_parent = NULL;
+    fallback_sign_good = 0;
 
     for( parent = candidates; parent != NULL; parent = parent->next )
     {
@@ -1988,17 +2048,38 @@
         }
 
         /* Signature */
-        if( top && x509_crt_check_signature( child, parent ) != 0 )
+#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
+check_signature:
+#endif
+        ret = x509_crt_check_signature( child, parent, rs_ctx );
+
+#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
+        if( rs_ctx != NULL && ret == MBEDTLS_ERR_ECP_IN_PROGRESS )
         {
-            continue;
+            /* save state */
+            rs_ctx->parent = parent;
+            rs_ctx->fallback_parent = fallback_parent;
+            rs_ctx->fallback_sign_good = fallback_sign_good;
+
+            return( ret );
         }
+#else
+        (void) ret;
+#endif
+
+        signature_is_good = ret == 0;
+        if( top && ! signature_is_good )
+            continue;
 
         /* optional time check */
         if( mbedtls_x509_time_is_past( &parent->valid_to ) ||
             mbedtls_x509_time_is_future( &parent->valid_from ) )
         {
-            if( badtime_parent == NULL )
-                badtime_parent = parent;
+            if( fallback_parent == NULL )
+            {
+                fallback_parent = parent;
+                fallback_sign_good = signature_is_good;
+            }
 
             continue;
         }
@@ -2006,10 +2087,18 @@
         break;
     }
 
-    if( parent == NULL )
-        parent = badtime_parent;
+    if( parent != NULL )
+    {
+        *r_parent = parent;
+        *r_signature_is_good = signature_is_good;
+    }
+    else
+    {
+        *r_parent = fallback_parent;
+        *r_signature_is_good = fallback_sign_good;
+    }
 
-    return( parent );
+    return( 0 );
 }
 
 /*
@@ -2021,34 +2110,78 @@
  * Arguments:
  *  - [in] child: certificate for which we're looking for a parent, followed
  *         by a chain of possible intermediates
- *  - [in] trust_ca: locally trusted CAs
- *  - [out] 1 if parent was found in trust_ca, 0 if found in provided chain
- *  - [in] path_cnt: number of intermediates seen so far
- *  - [in] self_cnt: number of self-signed intermediates seen so far
+ *  - [in] trust_ca: list of locally trusted certificates
+ *  - [out] parent: parent found (or NULL)
+ *  - [out] parent_is_trusted: 1 if returned `parent` is trusted, or 0
+ *  - [out] signature_is_good: 1 if child signature by parent is valid, or 0
+ *  - [in] path_cnt: number of links in the chain so far (EE -> ... -> child)
+ *  - [in] self_cnt: number of self-signed certs in the chain so far
  *         (will always be no greater than path_cnt)
+ *  - [in-out] rs_ctx: context for restarting operations
  *
  * Return value:
- *  - the first suitable parent found (see find_parent_in() for "suitable")
- *  - NULL if no suitable parent was found
+ *  - 0 on success
+ *  - MBEDTLS_ERR_ECP_IN_PROGRESS otherwise
  */
-static mbedtls_x509_crt *x509_crt_find_parent( mbedtls_x509_crt *child,
-                                               mbedtls_x509_crt *trust_ca,
-                                               int *parent_is_trusted,
-                                               size_t path_cnt,
-                                               size_t self_cnt )
+static int x509_crt_find_parent(
+                        mbedtls_x509_crt *child,
+                        mbedtls_x509_crt *trust_ca,
+                        mbedtls_x509_crt **parent,
+                        int *parent_is_trusted,
+                        int *signature_is_good,
+                        unsigned path_cnt,
+                        unsigned self_cnt,
+                        mbedtls_x509_crt_restart_ctx *rs_ctx )
 {
-    mbedtls_x509_crt *parent;
+    int ret;
+    mbedtls_x509_crt *search_list;
 
-    /* Look for a parent in trusted CAs */
     *parent_is_trusted = 1;
-    parent = x509_crt_find_parent_in( child, trust_ca, 1, path_cnt, self_cnt );
 
-    if( parent != NULL )
-        return( parent );
+#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
+    /* restore then clear saved state if we have some stored */
+    if( rs_ctx != NULL && rs_ctx->parent_is_trusted != -1 )
+    {
+        *parent_is_trusted = rs_ctx->parent_is_trusted;
+        rs_ctx->parent_is_trusted = -1;
+    }
+#endif
 
-    /* Look for a parent upwards the chain */
-    *parent_is_trusted = 0;
-    return( x509_crt_find_parent_in( child, child->next, 0, path_cnt, self_cnt ) );
+    while( 1 ) {
+        search_list = *parent_is_trusted ? trust_ca : child->next;
+
+        ret = x509_crt_find_parent_in( child, search_list,
+                                       parent, signature_is_good,
+                                       *parent_is_trusted,
+                                       path_cnt, self_cnt, rs_ctx );
+
+#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
+        if( rs_ctx != NULL && ret == MBEDTLS_ERR_ECP_IN_PROGRESS )
+        {
+            /* save state */
+            rs_ctx->parent_is_trusted = *parent_is_trusted;
+            return( ret );
+        }
+#else
+        (void) ret;
+#endif
+
+        /* stop here if found or already in second iteration */
+        if( *parent != NULL || *parent_is_trusted == 0 )
+            break;
+
+        /* prepare second iteration */
+        *parent_is_trusted = 0;
+    }
+
+    /* extra precaution against mistakes in the caller */
+    if( parent == NULL )
+    {
+        parent_is_trusted = 0;
+        signature_is_good = 0;
+    }
+
+    return( 0 );
 }
 
 /*
@@ -2097,11 +2230,24 @@
  * - EE, Ci1, ..., Ciq cannot be continued with a trusted root
  *   -> return that chain with NOT_TRUSTED set on Ciq
  *
+ * Tests for (aspects of) this function should include at least:
+ * - trusted EE
+ * - EE -> trusted root
+ * - EE -> intermedate CA -> trusted root
+ * - if relevant: EE untrusted
+ * - if relevant: EE -> intermediate, untrusted
+ * with the aspect under test checked at each relevant level (EE, int, root).
+ * For some aspects longer chains are required, but usually length 2 is
+ * enough (but length 1 is not in general).
+ *
  * Arguments:
  *  - [in] crt: the cert list EE, C1, ..., Cn
  *  - [in] trust_ca: the trusted list R1, ..., Rp
  *  - [in] ca_crl, profile: as in verify_with_profile()
- *  - [out] ver_chain, chain_len: the built and verified chain
+ *  - [out] ver_chain: the built and verified chain
+ *      Only valid when return value is 0, may contain garbage otherwise!
+ *      Restart note: need not be the same when calling again to resume.
+ *  - [in-out] rs_ctx: context for restarting operations
  *
  * Return value:
  *  - non-zero if the chain could not be fully built and examined
@@ -2113,24 +2259,50 @@
                 mbedtls_x509_crt *trust_ca,
                 mbedtls_x509_crl *ca_crl,
                 const mbedtls_x509_crt_profile *profile,
-                x509_crt_verify_chain_item ver_chain[X509_MAX_VERIFY_CHAIN_SIZE],
-                size_t *chain_len )
+                mbedtls_x509_crt_verify_chain *ver_chain,
+                mbedtls_x509_crt_restart_ctx *rs_ctx )
 {
+    /* Don't initialize any of those variables here, so that the compiler can
+     * catch potential issues with jumping ahead when restarting */
+    int ret;
     uint32_t *flags;
+    mbedtls_x509_crt_verify_chain_item *cur;
     mbedtls_x509_crt *child;
     mbedtls_x509_crt *parent;
-    int parent_is_trusted = 0;
-    int child_is_trusted = 0;
-    size_t self_cnt = 0;
+    int parent_is_trusted;
+    int child_is_trusted;
+    int signature_is_good;
+    unsigned self_cnt;
+
+#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
+    /* resume if we had an operation in progress */
+    if( rs_ctx != NULL && rs_ctx->in_progress == x509_crt_rs_find_parent )
+    {
+        /* restore saved state */
+        *ver_chain = rs_ctx->ver_chain; /* struct copy */
+        self_cnt = rs_ctx->self_cnt;
+
+        /* restore derived state */
+        cur = &ver_chain->items[ver_chain->len - 1];
+        child = cur->crt;
+        flags = &cur->flags;
+
+        goto find_parent;
+    }
+#endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
 
     child = crt;
-    *chain_len = 0;
+    self_cnt = 0;
+    parent_is_trusted = 0;
+    child_is_trusted = 0;
 
     while( 1 ) {
         /* Add certificate to the verification chain */
-        ver_chain[*chain_len].crt = child;
-        flags = &ver_chain[*chain_len].flags;
-        ++*chain_len;
+        cur = &ver_chain->items[ver_chain->len];
+        cur->crt = child;
+        cur->flags = 0;
+        ver_chain->len++;
+        flags = &cur->flags;
 
         /* Check time-validity (all certificates) */
         if( mbedtls_x509_time_is_past( &child->valid_to ) )
@@ -2151,15 +2323,33 @@
             *flags |= MBEDTLS_X509_BADCERT_BAD_PK;
 
         /* Special case: EE certs that are locally trusted */
-        if( *chain_len == 1 &&
+        if( ver_chain->len == 1 &&
             x509_crt_check_ee_locally_trusted( child, trust_ca ) == 0 )
         {
             return( 0 );
         }
 
+#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
+find_parent:
+#endif
         /* Look for a parent in trusted CAs or up the chain */
-        parent = x509_crt_find_parent( child, trust_ca, &parent_is_trusted,
-                                       *chain_len - 1, self_cnt );
+        ret = x509_crt_find_parent( child, trust_ca, &parent,
+                                       &parent_is_trusted, &signature_is_good,
+                                       ver_chain->len - 1, self_cnt, rs_ctx );
+
+#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
+        if( rs_ctx != NULL && ret == MBEDTLS_ERR_ECP_IN_PROGRESS )
+        {
+            /* save state */
+            rs_ctx->in_progress = x509_crt_rs_find_parent;
+            rs_ctx->self_cnt = self_cnt;
+            rs_ctx->ver_chain = *ver_chain; /* struct copy */
+
+            return( ret );
+        }
+#else
+        (void) ret;
+#endif
 
         /* No parent? We're done here */
         if( parent == NULL )
@@ -2171,7 +2361,7 @@
         /* Count intermediate self-issued (not necessarily self-signed) certs.
          * These can occur with some strategies for key rollover, see [SIRO],
          * and should be excluded from max_pathlen checks. */
-        if( *chain_len != 1 &&
+        if( ver_chain->len != 1 &&
             x509_name_cmp( &child->issuer, &child->subject ) == 0 )
         {
             self_cnt++;
@@ -2180,14 +2370,14 @@
         /* path_cnt is 0 for the first intermediate CA,
          * and if parent is trusted it's not an intermediate CA */
         if( ! parent_is_trusted &&
-            *chain_len > MBEDTLS_X509_MAX_INTERMEDIATE_CA )
+            ver_chain->len > MBEDTLS_X509_MAX_INTERMEDIATE_CA )
         {
             /* return immediately to avoid overflow the chain array */
             return( MBEDTLS_ERR_X509_FATAL_ERROR );
         }
 
-        /* if parent is trusted, the signature was checked by find_parent() */
-        if( ! parent_is_trusted && x509_crt_check_signature( child, parent ) != 0 )
+        /* signature was checked while searching parent */
+        if( ! signature_is_good )
             *flags |= MBEDTLS_X509_BADCERT_NOT_TRUSTED;
 
         /* check size of signing key */
@@ -2205,6 +2395,7 @@
         child = parent;
         parent = NULL;
         child_is_trusted = parent_is_trusted;
+        signature_is_good = 0;
     }
 }
 
@@ -2273,21 +2464,22 @@
  */
 static int x509_crt_merge_flags_with_cb(
            uint32_t *flags,
-           x509_crt_verify_chain_item ver_chain[X509_MAX_VERIFY_CHAIN_SIZE],
-           size_t chain_len,
+           const mbedtls_x509_crt_verify_chain *ver_chain,
            int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
            void *p_vrfy )
 {
     int ret;
-    size_t i;
+    unsigned i;
     uint32_t cur_flags;
+    const mbedtls_x509_crt_verify_chain_item *cur;
 
-    for( i = chain_len; i != 0; --i )
+    for( i = ver_chain->len; i != 0; --i )
     {
-        cur_flags = ver_chain[i-1].flags;
+        cur = &ver_chain->items[i-1];
+        cur_flags = cur->flags;
 
         if( NULL != f_vrfy )
-            if( ( ret = f_vrfy( p_vrfy, ver_chain[i-1].crt, (int) i-1, &cur_flags ) ) != 0 )
+            if( ( ret = f_vrfy( p_vrfy, cur->crt, (int) i-1, &cur_flags ) ) != 0 )
                 return( ret );
 
         *flags |= cur_flags;
@@ -2297,7 +2489,7 @@
 }
 
 /*
- * Verify the certificate validity
+ * Verify the certificate validity (default profile, not restartable)
  */
 int mbedtls_x509_crt_verify( mbedtls_x509_crt *crt,
                      mbedtls_x509_crt *trust_ca,
@@ -2306,19 +2498,13 @@
                      int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
                      void *p_vrfy )
 {
-    return( mbedtls_x509_crt_verify_with_profile( crt, trust_ca, ca_crl,
-                &mbedtls_x509_crt_profile_default, cn, flags, f_vrfy, p_vrfy ) );
+    return( mbedtls_x509_crt_verify_restartable( crt, trust_ca, ca_crl,
+                &mbedtls_x509_crt_profile_default, cn, flags,
+                f_vrfy, p_vrfy, NULL ) );
 }
 
 /*
- * Verify the certificate validity, with profile
- *
- * This function:
- *  - checks the requested CN (if any)
- *  - checks the type and size of the EE cert's key,
- *    as that isn't done as part of chain building/verification currently
- *  - builds and verifies the chain
- *  - then calls the callback and merges the flags
+ * Verify the certificate validity (user-chosen profile, not restartable)
  */
 int mbedtls_x509_crt_verify_with_profile( mbedtls_x509_crt *crt,
                      mbedtls_x509_crt *trust_ca,
@@ -2328,15 +2514,37 @@
                      int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
                      void *p_vrfy )
 {
+    return( mbedtls_x509_crt_verify_restartable( crt, trust_ca, ca_crl,
+                profile, cn, flags, f_vrfy, p_vrfy, NULL ) );
+}
+
+/*
+ * Verify the certificate validity, with profile, restartable version
+ *
+ * This function:
+ *  - checks the requested CN (if any)
+ *  - checks the type and size of the EE cert's key,
+ *    as that isn't done as part of chain building/verification currently
+ *  - builds and verifies the chain
+ *  - then calls the callback and merges the flags
+ */
+int mbedtls_x509_crt_verify_restartable( mbedtls_x509_crt *crt,
+                     mbedtls_x509_crt *trust_ca,
+                     mbedtls_x509_crl *ca_crl,
+                     const mbedtls_x509_crt_profile *profile,
+                     const char *cn, uint32_t *flags,
+                     int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
+                     void *p_vrfy,
+                     mbedtls_x509_crt_restart_ctx *rs_ctx )
+{
     int ret;
     mbedtls_pk_type_t pk_type;
-    x509_crt_verify_chain_item ver_chain[X509_MAX_VERIFY_CHAIN_SIZE];
-    size_t chain_len;
-    uint32_t *ee_flags = &ver_chain[0].flags;
+    mbedtls_x509_crt_verify_chain ver_chain;
+    uint32_t ee_flags;
 
     *flags = 0;
-    memset( ver_chain, 0, sizeof( ver_chain ) );
-    chain_len = 0;
+    ee_flags = 0;
+    x509_crt_verify_chain_reset( &ver_chain );
 
     if( profile == NULL )
     {
@@ -2346,28 +2554,36 @@
 
     /* check name if requested */
     if( cn != NULL )
-        x509_crt_verify_name( crt, cn, ee_flags );
+        x509_crt_verify_name( crt, cn, &ee_flags );
 
     /* Check the type and size of the key */
     pk_type = mbedtls_pk_get_type( &crt->pk );
 
     if( x509_profile_check_pk_alg( profile, pk_type ) != 0 )
-        *ee_flags |= MBEDTLS_X509_BADCERT_BAD_PK;
+        ee_flags |= MBEDTLS_X509_BADCERT_BAD_PK;
 
     if( x509_profile_check_key( profile, &crt->pk ) != 0 )
-        *ee_flags |= MBEDTLS_X509_BADCERT_BAD_KEY;
+        ee_flags |= MBEDTLS_X509_BADCERT_BAD_KEY;
 
     /* Check the chain */
     ret = x509_crt_verify_chain( crt, trust_ca, ca_crl, profile,
-                                 ver_chain, &chain_len );
+                                 &ver_chain, rs_ctx );
+
     if( ret != 0 )
         goto exit;
 
+    /* Merge end-entity flags */
+    ver_chain.items[0].flags |= ee_flags;
+
     /* Build final flags, calling callback on the way if any */
-    ret = x509_crt_merge_flags_with_cb( flags,
-                                        ver_chain, chain_len, f_vrfy, p_vrfy );
+    ret = x509_crt_merge_flags_with_cb( flags, &ver_chain, f_vrfy, p_vrfy );
 
 exit:
+#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
+    if( rs_ctx != NULL && ret != MBEDTLS_ERR_ECP_IN_PROGRESS )
+        mbedtls_x509_crt_restart_free( rs_ctx );
+#endif
+
     /* prevent misuse of the vrfy callback - VERIFY_FAILED would be ignored by
      * the SSL module for authmode optional, but non-zero return from the
      * callback means a fatal error so it shouldn't be ignored */
@@ -2478,4 +2694,37 @@
     while( cert_cur != NULL );
 }
 
+#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
+/*
+ * Initialize a restart context
+ */
+void mbedtls_x509_crt_restart_init( mbedtls_x509_crt_restart_ctx *ctx )
+{
+    mbedtls_pk_restart_init( &ctx->pk );
+
+    ctx->parent = NULL;
+    ctx->fallback_parent = NULL;
+    ctx->fallback_sign_good = 0;
+
+    ctx->parent_is_trusted = -1;
+
+    ctx->in_progress = x509_crt_rs_none;
+    ctx->self_cnt = 0;
+    x509_crt_verify_chain_reset( &ctx->ver_chain );
+}
+
+/*
+ * Free the components of a restart context
+ */
+void mbedtls_x509_crt_restart_free( mbedtls_x509_crt_restart_ctx *ctx )
+{
+    if( ctx == NULL )
+        return;
+
+    mbedtls_pk_restart_free( &ctx->pk );
+
+    mbedtls_x509_crt_restart_init( ctx );
+}
+#endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
+
 #endif /* MBEDTLS_X509_CRT_PARSE_C */
diff --git a/programs/ssl/ssl_client2.c b/programs/ssl/ssl_client2.c
index 5d8969d..b11bedd 100644
--- a/programs/ssl/ssl_client2.c
+++ b/programs/ssl/ssl_client2.c
@@ -83,6 +83,7 @@
 #define DFL_PSK                 ""
 #define DFL_PSK_IDENTITY        "Client_identity"
 #define DFL_ECJPAKE_PW          NULL
+#define DFL_EC_MAX_OPS          -1
 #define DFL_FORCE_CIPHER        0
 #define DFL_RENEGOTIATION       MBEDTLS_SSL_RENEGOTIATION_DISABLED
 #define DFL_ALLOW_LEGACY        -2
@@ -239,6 +240,13 @@
 #define USAGE_ECJPAKE ""
 #endif
 
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+#define USAGE_ECRESTART \
+    "    ec_max_ops=%%s       default: library default (restart disabled)\n"
+#else
+#define USAGE_ECRESTART ""
+#endif
+
 #define USAGE \
     "\n usage: ssl_client2 param=<>...\n"                   \
     "\n acceptable parameters:\n"                           \
@@ -264,6 +272,7 @@
     "\n"                                                    \
     USAGE_PSK                                               \
     USAGE_ECJPAKE                                           \
+    USAGE_ECRESTART                                         \
     "\n"                                                    \
     "    allow_legacy=%%d     default: (library default: no)\n"   \
     USAGE_RENEGO                                            \
@@ -317,6 +326,7 @@
     const char *psk;            /* the pre-shared key                       */
     const char *psk_identity;   /* the pre-shared key identity              */
     const char *ecjpake_pw;     /* the EC J-PAKE password                   */
+    int ec_max_ops;             /* EC consecutive operations limit          */
     int force_ciphersuite[2];   /* protocol/ciphersuite to use, or all      */
     int renegotiation;          /* enable / disable renegotiation           */
     int allow_legacy;           /* allow legacy renegotiation               */
@@ -590,6 +600,7 @@
     opt.psk                 = DFL_PSK;
     opt.psk_identity        = DFL_PSK_IDENTITY;
     opt.ecjpake_pw          = DFL_ECJPAKE_PW;
+    opt.ec_max_ops          = DFL_EC_MAX_OPS;
     opt.force_ciphersuite[0]= DFL_FORCE_CIPHER;
     opt.renegotiation       = DFL_RENEGOTIATION;
     opt.allow_legacy        = DFL_ALLOW_LEGACY;
@@ -689,6 +700,8 @@
             opt.psk_identity = q;
         else if( strcmp( p, "ecjpake_pw" ) == 0 )
             opt.ecjpake_pw = q;
+        else if( strcmp( p, "ec_max_ops" ) == 0 )
+            opt.ec_max_ops = atoi( q );
         else if( strcmp( p, "force_ciphersuite" ) == 0 )
         {
             opt.force_ciphersuite[0] = mbedtls_ssl_get_ciphersuite_id( q );
@@ -1486,6 +1499,11 @@
                                             mbedtls_timing_get_delay );
 #endif
 
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+    if( opt.ec_max_ops != DFL_EC_MAX_OPS )
+        mbedtls_ecp_set_max_ops( opt.ec_max_ops );
+#endif
+
     mbedtls_printf( " ok\n" );
 
     /*
@@ -1497,7 +1515,8 @@
     while( ( ret = mbedtls_ssl_handshake( &ssl ) ) != 0 )
     {
         if( ret != MBEDTLS_ERR_SSL_WANT_READ &&
-            ret != MBEDTLS_ERR_SSL_WANT_WRITE )
+            ret != MBEDTLS_ERR_SSL_WANT_WRITE &&
+            ret != MBEDTLS_ERR_ECP_IN_PROGRESS )
         {
             mbedtls_printf( " failed\n  ! mbedtls_ssl_handshake returned -0x%x\n",
                             -ret );
@@ -1513,6 +1532,11 @@
             goto exit;
         }
 
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+            if( ret == MBEDTLS_ERR_ECP_IN_PROGRESS )
+                continue;
+#endif
+
         /* For event-driven IO, wait for socket to become available */
         if( opt.event == 1 /* level triggered IO */ )
         {
@@ -1605,7 +1629,8 @@
         while( ( ret = mbedtls_ssl_renegotiate( &ssl ) ) != 0 )
         {
             if( ret != MBEDTLS_ERR_SSL_WANT_READ &&
-                ret != MBEDTLS_ERR_SSL_WANT_WRITE )
+                ret != MBEDTLS_ERR_SSL_WANT_WRITE &&
+                ret != MBEDTLS_ERR_ECP_IN_PROGRESS )
             {
                 mbedtls_printf( " failed\n  ! mbedtls_ssl_renegotiate returned %d\n\n",
                                 ret );
@@ -1669,7 +1694,8 @@
                                               len - written ) ) <= 0 )
             {
                 if( ret != MBEDTLS_ERR_SSL_WANT_READ &&
-                    ret != MBEDTLS_ERR_SSL_WANT_WRITE )
+                    ret != MBEDTLS_ERR_SSL_WANT_WRITE &&
+                    ret != MBEDTLS_ERR_ECP_IN_PROGRESS )
                 {
                     mbedtls_printf( " failed\n  ! mbedtls_ssl_write returned -0x%x\n\n",
                                     -ret );
@@ -1694,6 +1720,11 @@
         {
             ret = mbedtls_ssl_write( &ssl, buf, len );
 
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+            if( ret == MBEDTLS_ERR_ECP_IN_PROGRESS )
+                continue;
+#endif
+
             if( ret != MBEDTLS_ERR_SSL_WANT_READ &&
                 ret != MBEDTLS_ERR_SSL_WANT_WRITE )
                 break;
@@ -1747,6 +1778,11 @@
             memset( buf, 0, sizeof( buf ) );
             ret = mbedtls_ssl_read( &ssl, buf, len );
 
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+            if( ret == MBEDTLS_ERR_ECP_IN_PROGRESS )
+                continue;
+#endif
+
             if( ret == MBEDTLS_ERR_SSL_WANT_READ ||
                 ret == MBEDTLS_ERR_SSL_WANT_WRITE )
             {
@@ -1807,6 +1843,11 @@
         {
             ret = mbedtls_ssl_read( &ssl, buf, len );
 
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+            if( ret == MBEDTLS_ERR_ECP_IN_PROGRESS )
+                continue;
+#endif
+
             if( ret != MBEDTLS_ERR_SSL_WANT_READ &&
                 ret != MBEDTLS_ERR_SSL_WANT_WRITE )
                 break;
@@ -1869,7 +1910,8 @@
         while( ( ret = mbedtls_ssl_handshake( &ssl ) ) != 0 )
         {
             if( ret != MBEDTLS_ERR_SSL_WANT_READ &&
-                ret != MBEDTLS_ERR_SSL_WANT_WRITE )
+                ret != MBEDTLS_ERR_SSL_WANT_WRITE &&
+                ret != MBEDTLS_ERR_ECP_IN_PROGRESS )
             {
                 mbedtls_printf( " failed\n  ! mbedtls_ssl_handshake returned -0x%x\n\n",
                                 -ret );
@@ -1967,7 +2009,8 @@
         while( ( ret = mbedtls_ssl_handshake( &ssl ) ) != 0 )
         {
             if( ret != MBEDTLS_ERR_SSL_WANT_READ &&
-                ret != MBEDTLS_ERR_SSL_WANT_WRITE )
+                ret != MBEDTLS_ERR_SSL_WANT_WRITE &&
+                ret != MBEDTLS_ERR_ECP_IN_PROGRESS )
             {
                 mbedtls_printf( " failed\n  ! mbedtls_ssl_handshake returned -0x%x\n\n",
                                 -ret );
diff --git a/tests/data_files/Makefile b/tests/data_files/Makefile
index 4a24352..df2c034 100644
--- a/tests/data_files/Makefile
+++ b/tests/data_files/Makefile
@@ -113,7 +113,7 @@
 	$(FAKETIME) -f +3653d $(OPENSSL) x509 -req -extfile $(cli_crt_extensions_file) -extensions cli-rsa -CA $(test_ca_int_rsa1) -CAkey test-int-ca.key -set_serial 16 -days 3653 -sha256 -in server7.csr | cat - $(test_ca_int_rsa1) > $@
 all_final += server7-future.crt
 server7-badsign.crt: server7.crt $(test_ca_int_rsa1)
-	{ head -n-2 server7.crt; tail -n-2 server7.crt | sed -e '1s/0\(=*\)$$/_\1/' -e '1s/[^_=]\(=*\)$$/0\1/' -e '1s/_/1/'; cat test-int-ca.crt; } > server7-badsign.crt
+	{ head -n-2 $<; tail -n-2 $< | sed -e '1s/0\(=*\)$$/_\1/' -e '1s/[^_=]\(=*\)$$/0\1/' -e '1s/_/1/'; cat $(test_ca_int_rsa1); } > $@
 all_final += server7-badsign.crt
 server7_int-ca-exp.crt: server7.crt test-int-ca-exp.crt
 	cat server7.crt test-int-ca-exp.crt > $@
@@ -128,6 +128,19 @@
 	$(FAKETIME) '2015-09-01 14:08:43' $(OPENSSL) req -x509 -new -subj "/C=UK/O=mbed TLS/CN=mbed TLS Test intermediate CA 3" -set_serial 77 -config $(test_ca_config_file) -extensions noext_ca -days 3650 -sha256 -key $< -out $@
 all_final += server5-ss-forgeca.crt
 
+server10-badsign.crt: server10.crt
+	{ head -n-2 $<; tail -n-2 $< | sed -e '1s/0\(=*\)$$/_\1/' -e '1s/[^_=]\(=*\)$$/0\1/' -e '1s/_/1/'; } > $@
+all_final += server10-badsign.crt
+server10-bs_int3.pem: server10-badsign.crt test-int-ca3.crt
+	cat server10-badsign.crt test-int-ca3.crt > $@
+all_final += server10-bs_int3.pem
+test-int-ca3-badsign.crt: test-int-ca3.crt
+	{ head -n-2 $<; tail -n-2 $< | sed -e '1s/0\(=*\)$$/_\1/' -e '1s/[^_=]\(=*\)$$/0\1/' -e '1s/_/1/'; } > $@
+all_final += test-int-ca3-badsign.crt
+server10_int3-bs.pem: server10.crt test-int-ca3-badsign.crt
+	cat server10.crt test-int-ca3-badsign.crt > $@
+all_final += server10-bs_int3-bs.pem
+
 rsa_pkcs1_2048_public.pem: server8.key
 	$(OPENSSL)  rsa -in $< -outform PEM -RSAPublicKey_out -out $@
 all_final += rsa_pkcs1_2048_public.pem
diff --git a/tests/data_files/Readme-x509.txt b/tests/data_files/Readme-x509.txt
index b56346a..6f54ed0 100644
--- a/tests/data_files/Readme-x509.txt
+++ b/tests/data_files/Readme-x509.txt
@@ -16,11 +16,13 @@
 Two intermediate CAs are signed by them:
 - test-int-ca.crt "C=NL, O=PolarSSL, CN=PolarSSL Test Intermediate CA"
   uses RSA-4096, signed by test-ca2
+    - test-int-ca-exp.crt is a copy that is expired
 - test-int-ca2.crt "C=NL, O=PolarSSL, CN=PolarSSL Test Intermediate EC CA"
-  uses an EC key with NIST P-256, signed by test-ca
+  uses an EC key with NIST P-384, signed by test-ca
 
 A third intermediate CA is signed by test-int-ca2.crt:
 - test-int-ca3.crt "C=UK, O=mbed TLS, CN=mbed TLS Test intermediate CA 3"
+  uses an EC key with NIST P-256, signed by test-int-ca2
 
 Finally, other CAs for specific purposes:
 - enco-ca-prstr.pem: has its CN encoded as a printable string, but child cert
@@ -65,21 +67,41 @@
 - server2*.crt: 1 R L: misc
 - server3.crt: 1 E L: EC cert signed by RSA CA
 - server4.crt: 2 R L: RSA cert signed by EC CA
-- server5*.crt: 2* E L: misc *(except server5-selfsigned)
+- server5*.crt: 2* E L: misc *(except -selfsigned and -ss-*)
     -sha*: hashes
-    -eku*: extendeKeyUsage (cli/srv = www client/server, cs = codesign, etc)
-    -ku*: keyUsage (ds = signatures, ke/ka = key exchange/agreement)
+    .eku*: extendeKeyUsage (cli/srv = www client/server, cs = codesign, etc)
+    .ku*: keyUsage (ds = signatures, ke/ka = key exchange/agreement)
+    .req*: CSR, not certificate
+    -der*: trailing bytes in der (?)
+    -badsign.crt: S5 with corrupted signature
+    -expired.crt: S5 with "not after" date in the past
+    -future.crt: S5 with "not before" date in the future
+    -selfsigned.crt: Self-signed cert with S5 key
+    -ss-expired.crt: Self-signed cert with S5 key, expired
+    -ss-forgeca.crt: Copy of test-int-ca3 self-signed with S5 key
 - server6-ss-child.crt: O E: "child" of non-CA server5-selfsigned
 - server6.crt, server6.pem: 2 E L C: revoked
-- server7*.crt: I1 E L P1*: EC signed by RSA signed by EC
-    *P1 except 7.crt, P2 _int-ca_ca2.crt
-    *_space: with PEM error(s)
-    _spurious: has spurious cert in its chain (S7 + I2 + I1)
+- server7.crt: I1 E L P1(usually): EC signed by RSA signed by EC
+    -badsign.crt: S7 with corrupted signature + I1
+    -expired.crt: S7 with "not after" date in the past + I1
+    -future.crt: S7 with "not before" date in the future + I1
+    _int-ca-exp.crt: S7 + expired I1
+    _int-ca.crt: S7 + I1
+    _int-ca_ca2.crt: S7 + I1 + 2
+    _all_space.crt: S7 + I1 both with misplaced spaces (invalid PEM)
+    _pem_space.crt: S7 with misplace space (invalid PEM) + I1
+    _trailing_space.crt: S7 + I1 both with trainling space (valid PEM)
+    _spurious_int-ca.crt: S7 + I2(spurious) + I1
 - server8*.crt: I2 R L: RSA signed by EC signed by RSA (P1 for _int-ca2)
 - server9*.crt: 1 R C* L P1*: signed using RSASSA-PSS
     *CRL for: 9.crt, -badsign, -with-ca (P1)
-- server10*.crt: I3 E L P2/P3
-    _spurious: S10 + I3 + I1(spurious) + I2
+- server10.crt: I3 E L
+    -badsign.crt: S10 with corrupted signature
+    -bs_int3.pem: S10-badsign + I3
+    _int3-bs.pem: S10 + I3-badsign
+    _int3_int-ca2.crt: S10 + I3 + I2
+    _int3_int-ca2_ca.crt: S10 + I3 + I2 + 1
+    _int3_spurious_int-ca2.crt: S10 + I3 + I1(spurious) + I2
 
 Certificate revocation lists
 ----------------------------
diff --git a/tests/data_files/server10-badsign.crt b/tests/data_files/server10-badsign.crt
new file mode 100644
index 0000000..eca171f
--- /dev/null
+++ b/tests/data_files/server10-badsign.crt
@@ -0,0 +1,10 @@
+-----BEGIN CERTIFICATE-----
+MIIBWjCCAQCgAwIBAgIBSzAKBggqhkjOPQQDAjBKMQswCQYDVQQGEwJVSzERMA8G
+A1UEChMIbWJlZCBUTFMxKDAmBgNVBAMTH21iZWQgVExTIFRlc3QgaW50ZXJtZWRp
+YXRlIENBIDMwHhcNMTUwOTAxMTM0NzU1WhcNMjUwODI5MTM0NzU1WjAUMRIwEAYD
+VQQDEwlsb2NhbGhvc3QwWTATBgcqhkjOPQIBBggqhkjOPQMBBwNCAAQcbffp2qXq
+oZyychmoCRxzrd4Vu96m47NPBehtEC46aTeXgDnBdf++znABrAtfXBRNQz8ARIeY
+Bmskr22rlKjyow0wCzAJBgNVHRMEAjAAMAoGCCqGSM49BAMCA0gAMEUCIQDLc+Io
+rg8VxEbCgVv8iH+kOIEn9MjhpvKzvwUoV+6rjQIgZU/RXAyc1a+H2+soGfNEIOBQ
+AzO3pJx7WJAApZuBX10=
+-----END CERTIFICATE-----
diff --git a/tests/data_files/server10-bs_int3.pem b/tests/data_files/server10-bs_int3.pem
new file mode 100644
index 0000000..b84cee7
--- /dev/null
+++ b/tests/data_files/server10-bs_int3.pem
@@ -0,0 +1,22 @@
+-----BEGIN CERTIFICATE-----
+MIIBWjCCAQCgAwIBAgIBSzAKBggqhkjOPQQDAjBKMQswCQYDVQQGEwJVSzERMA8G
+A1UEChMIbWJlZCBUTFMxKDAmBgNVBAMTH21iZWQgVExTIFRlc3QgaW50ZXJtZWRp
+YXRlIENBIDMwHhcNMTUwOTAxMTM0NzU1WhcNMjUwODI5MTM0NzU1WjAUMRIwEAYD
+VQQDEwlsb2NhbGhvc3QwWTATBgcqhkjOPQIBBggqhkjOPQMBBwNCAAQcbffp2qXq
+oZyychmoCRxzrd4Vu96m47NPBehtEC46aTeXgDnBdf++znABrAtfXBRNQz8ARIeY
+Bmskr22rlKjyow0wCzAJBgNVHRMEAjAAMAoGCCqGSM49BAMCA0gAMEUCIQDLc+Io
+rg8VxEbCgVv8iH+kOIEn9MjhpvKzvwUoV+6rjQIgZU/RXAyc1a+H2+soGfNEIOBQ
+AzO3pJx7WJAApZuBX10=
+-----END CERTIFICATE-----
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----
diff --git a/tests/data_files/server10.crt b/tests/data_files/server10.crt
new file mode 100644
index 0000000..96a4040
--- /dev/null
+++ b/tests/data_files/server10.crt
@@ -0,0 +1,10 @@
+-----BEGIN CERTIFICATE-----
+MIIBWjCCAQCgAwIBAgIBSzAKBggqhkjOPQQDAjBKMQswCQYDVQQGEwJVSzERMA8G
+A1UEChMIbWJlZCBUTFMxKDAmBgNVBAMTH21iZWQgVExTIFRlc3QgaW50ZXJtZWRp
+YXRlIENBIDMwHhcNMTUwOTAxMTM0NzU1WhcNMjUwODI5MTM0NzU1WjAUMRIwEAYD
+VQQDEwlsb2NhbGhvc3QwWTATBgcqhkjOPQIBBggqhkjOPQMBBwNCAAQcbffp2qXq
+oZyychmoCRxzrd4Vu96m47NPBehtEC46aTeXgDnBdf++znABrAtfXBRNQz8ARIeY
+Bmskr22rlKjyow0wCzAJBgNVHRMEAjAAMAoGCCqGSM49BAMCA0gAMEUCIQDLc+Io
+rg8VxEbCgVv8iH+kOIEn9MjhpvKzvwUoV+6rjQIgZU/RXAyc1a+H2+soGfNEIOBQ
+AzO3pJx7WJAApZuBX1Q=
+-----END CERTIFICATE-----
diff --git a/tests/data_files/server10_int3-bs.pem b/tests/data_files/server10_int3-bs.pem
new file mode 100644
index 0000000..a9e0615
--- /dev/null
+++ b/tests/data_files/server10_int3-bs.pem
@@ -0,0 +1,22 @@
+-----BEGIN CERTIFICATE-----
+MIIBWjCCAQCgAwIBAgIBSzAKBggqhkjOPQQDAjBKMQswCQYDVQQGEwJVSzERMA8G
+A1UEChMIbWJlZCBUTFMxKDAmBgNVBAMTH21iZWQgVExTIFRlc3QgaW50ZXJtZWRp
+YXRlIENBIDMwHhcNMTUwOTAxMTM0NzU1WhcNMjUwODI5MTM0NzU1WjAUMRIwEAYD
+VQQDEwlsb2NhbGhvc3QwWTATBgcqhkjOPQIBBggqhkjOPQMBBwNCAAQcbffp2qXq
+oZyychmoCRxzrd4Vu96m47NPBehtEC46aTeXgDnBdf++znABrAtfXBRNQz8ARIeY
+Bmskr22rlKjyow0wCzAJBgNVHRMEAjAAMAoGCCqGSM49BAMCA0gAMEUCIQDLc+Io
+rg8VxEbCgVv8iH+kOIEn9MjhpvKzvwUoV+6rjQIgZU/RXAyc1a+H2+soGfNEIOBQ
+AzO3pJx7WJAApZuBX1Q=
+-----END CERTIFICATE-----
+-----BEGIN CERTIFICATE-----
+MIIBtDCCATqgAwIBAgIBTTAKBggqhkjOPQQDAjBLMQswCQYDVQQGEwJOTDERMA8G
+A1UEChMIUG9sYXJTU0wxKTAnBgNVBAMTIFBvbGFyU1NMIFRlc3QgSW50ZXJtZWRp
+YXRlIEVDIENBMB4XDTE1MDkwMTE0MDg0M1oXDTI1MDgyOTE0MDg0M1owSjELMAkG
+A1UEBhMCVUsxETAPBgNVBAoTCG1iZWQgVExTMSgwJgYDVQQDEx9tYmVkIFRMUyBU
+ZXN0IGludGVybWVkaWF0ZSBDQSAzMFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAE
+732fWHLNPMPsP1U1ibXvb55erlEVMlpXBGsj+KYwVqU1XCmW9Z9hhP7X/5js/DX9
+2J/utoHyjUtVpQOzdTrbsaMQMA4wDAYDVR0TBAUwAwEB/zAKBggqhkjOPQQDAgNo
+ADBlAjAJRxbGRas3NBmk9MnGWXg7PT1xnRELHRWWIvfLdVQt06l1/xFg3ZuPdQdt
+Qh7CK80CMQD7wa1o1a8qyDKBfLN636uKmKGga0E+vYXBeFCy9oARBangGCB0B2vt
+pz590JvGWf0=
+-----END CERTIFICATE-----
diff --git a/tests/data_files/test-int-ca3-badsign.crt b/tests/data_files/test-int-ca3-badsign.crt
new file mode 100644
index 0000000..2087056
--- /dev/null
+++ b/tests/data_files/test-int-ca3-badsign.crt
@@ -0,0 +1,12 @@
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----
diff --git a/tests/ssl-opt.sh b/tests/ssl-opt.sh
index c4a10a2..d90c12e 100755
--- a/tests/ssl-opt.sh
+++ b/tests/ssl-opt.sh
@@ -4067,6 +4067,141 @@
             -c "16384 bytes written in 1 fragments" \
             -s "Read from client: 16384 bytes read"
 
+# Tests for restartable ECC
+
+requires_config_enabled MBEDTLS_ECP_RESTARTABLE
+run_test    "EC restart: TLS, default" \
+            "$P_SRV auth_mode=required" \
+            "$P_CLI force_ciphersuite=TLS-ECDHE-ECDSA-WITH-AES-128-GCM-SHA256 \
+             key_file=data_files/server5.key crt_file=data_files/server5.crt  \
+             debug_level=1" \
+            0 \
+            -C "x509_verify_cert.*4b80" \
+            -C "mbedtls_pk_verify.*4b80" \
+            -C "mbedtls_ecdh_make_public.*4b80" \
+            -C "mbedtls_pk_sign.*4b80"
+
+requires_config_enabled MBEDTLS_ECP_RESTARTABLE
+run_test    "EC restart: TLS, max_ops=0" \
+            "$P_SRV auth_mode=required" \
+            "$P_CLI force_ciphersuite=TLS-ECDHE-ECDSA-WITH-AES-128-GCM-SHA256 \
+             key_file=data_files/server5.key crt_file=data_files/server5.crt  \
+             debug_level=1 ec_max_ops=0" \
+            0 \
+            -C "x509_verify_cert.*4b80" \
+            -C "mbedtls_pk_verify.*4b80" \
+            -C "mbedtls_ecdh_make_public.*4b80" \
+            -C "mbedtls_pk_sign.*4b80"
+
+requires_config_enabled MBEDTLS_ECP_RESTARTABLE
+run_test    "EC restart: TLS, max_ops=65535" \
+            "$P_SRV auth_mode=required" \
+            "$P_CLI force_ciphersuite=TLS-ECDHE-ECDSA-WITH-AES-128-GCM-SHA256 \
+             key_file=data_files/server5.key crt_file=data_files/server5.crt  \
+             debug_level=1 ec_max_ops=65535" \
+            0 \
+            -C "x509_verify_cert.*4b80" \
+            -C "mbedtls_pk_verify.*4b80" \
+            -C "mbedtls_ecdh_make_public.*4b80" \
+            -C "mbedtls_pk_sign.*4b80"
+
+requires_config_enabled MBEDTLS_ECP_RESTARTABLE
+run_test    "EC restart: TLS, max_ops=1000" \
+            "$P_SRV auth_mode=required" \
+            "$P_CLI force_ciphersuite=TLS-ECDHE-ECDSA-WITH-AES-128-GCM-SHA256 \
+             key_file=data_files/server5.key crt_file=data_files/server5.crt  \
+             debug_level=1 ec_max_ops=1000" \
+            0 \
+            -c "x509_verify_cert.*4b80" \
+            -c "mbedtls_pk_verify.*4b80" \
+            -c "mbedtls_ecdh_make_public.*4b80" \
+            -c "mbedtls_pk_sign.*4b80"
+
+requires_config_enabled MBEDTLS_ECP_RESTARTABLE
+run_test    "EC restart: TLS, max_ops=1000, badsign" \
+            "$P_SRV auth_mode=required \
+             crt_file=data_files/server5-badsign.crt \
+             key_file=data_files/server5.key" \
+            "$P_CLI force_ciphersuite=TLS-ECDHE-ECDSA-WITH-AES-128-GCM-SHA256 \
+             key_file=data_files/server5.key crt_file=data_files/server5.crt  \
+             debug_level=1 ec_max_ops=1000" \
+            1 \
+            -c "x509_verify_cert.*4b80" \
+            -C "mbedtls_pk_verify.*4b80" \
+            -C "mbedtls_ecdh_make_public.*4b80" \
+            -C "mbedtls_pk_sign.*4b80" \
+            -c "! The certificate is not correctly signed by the trusted CA" \
+            -c "! mbedtls_ssl_handshake returned" \
+            -c "X509 - Certificate verification failed"
+
+requires_config_enabled MBEDTLS_ECP_RESTARTABLE
+run_test    "EC restart: TLS, max_ops=1000, auth_mode=optional badsign" \
+            "$P_SRV auth_mode=required \
+             crt_file=data_files/server5-badsign.crt \
+             key_file=data_files/server5.key" \
+            "$P_CLI force_ciphersuite=TLS-ECDHE-ECDSA-WITH-AES-128-GCM-SHA256 \
+             key_file=data_files/server5.key crt_file=data_files/server5.crt  \
+             debug_level=1 ec_max_ops=1000 auth_mode=optional" \
+            0 \
+            -c "x509_verify_cert.*4b80" \
+            -c "mbedtls_pk_verify.*4b80" \
+            -c "mbedtls_ecdh_make_public.*4b80" \
+            -c "mbedtls_pk_sign.*4b80" \
+            -c "! The certificate is not correctly signed by the trusted CA" \
+            -C "! mbedtls_ssl_handshake returned" \
+            -C "X509 - Certificate verification failed"
+
+requires_config_enabled MBEDTLS_ECP_RESTARTABLE
+run_test    "EC restart: TLS, max_ops=1000, auth_mode=none badsign" \
+            "$P_SRV auth_mode=required \
+             crt_file=data_files/server5-badsign.crt \
+             key_file=data_files/server5.key" \
+            "$P_CLI force_ciphersuite=TLS-ECDHE-ECDSA-WITH-AES-128-GCM-SHA256 \
+             key_file=data_files/server5.key crt_file=data_files/server5.crt  \
+             debug_level=1 ec_max_ops=1000 auth_mode=none" \
+            0 \
+            -C "x509_verify_cert.*4b80" \
+            -c "mbedtls_pk_verify.*4b80" \
+            -c "mbedtls_ecdh_make_public.*4b80" \
+            -c "mbedtls_pk_sign.*4b80" \
+            -C "! The certificate is not correctly signed by the trusted CA" \
+            -C "! mbedtls_ssl_handshake returned" \
+            -C "X509 - Certificate verification failed"
+
+requires_config_enabled MBEDTLS_ECP_RESTARTABLE
+run_test    "EC restart: DTLS, max_ops=1000" \
+            "$P_SRV auth_mode=required dtls=1" \
+            "$P_CLI force_ciphersuite=TLS-ECDHE-ECDSA-WITH-AES-128-GCM-SHA256 \
+             key_file=data_files/server5.key crt_file=data_files/server5.crt  \
+             dtls=1 debug_level=1 ec_max_ops=1000" \
+            0 \
+            -c "x509_verify_cert.*4b80" \
+            -c "mbedtls_pk_verify.*4b80" \
+            -c "mbedtls_ecdh_make_public.*4b80" \
+            -c "mbedtls_pk_sign.*4b80"
+
+requires_config_enabled MBEDTLS_ECP_RESTARTABLE
+run_test    "EC restart: TLS, max_ops=1000 no client auth" \
+            "$P_SRV" \
+            "$P_CLI force_ciphersuite=TLS-ECDHE-ECDSA-WITH-AES-128-GCM-SHA256 \
+             debug_level=1 ec_max_ops=1000" \
+            0 \
+            -c "x509_verify_cert.*4b80" \
+            -c "mbedtls_pk_verify.*4b80" \
+            -c "mbedtls_ecdh_make_public.*4b80" \
+            -C "mbedtls_pk_sign.*4b80"
+
+requires_config_enabled MBEDTLS_ECP_RESTARTABLE
+run_test    "EC restart: TLS, max_ops=1000, ECDHE-PSK" \
+            "$P_SRV psk=abc123" \
+            "$P_CLI force_ciphersuite=TLS-ECDHE-PSK-WITH-AES-128-CBC-SHA256 \
+             psk=abc123 debug_level=1 ec_max_ops=1000" \
+            0 \
+            -C "x509_verify_cert.*4b80" \
+            -C "mbedtls_pk_verify.*4b80" \
+            -C "mbedtls_ecdh_make_public.*4b80" \
+            -C "mbedtls_pk_sign.*4b80"
+
 # Tests for DTLS HelloVerifyRequest
 
 run_test    "DTLS cookie: enabled" \
diff --git a/tests/suites/test_suite_ecdh.data b/tests/suites/test_suite_ecdh.data
index f7119de..0165a7e 100644
--- a/tests/suites/test_suite_ecdh.data
+++ b/tests/suites/test_suite_ecdh.data
@@ -37,3 +37,35 @@
 ECDH exchange #2
 depends_on:MBEDTLS_ECP_DP_SECP521R1_ENABLED
 ecdh_exchange:MBEDTLS_ECP_DP_SECP521R1
+
+ECDH restartable rfc 5903 p256 restart enabled max_ops=0 (disabled)
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecdh_restart:MBEDTLS_ECP_DP_SECP256R1:"C88F01F510D9AC3F70A292DAA2316DE544E9AAB8AFE84049C62A9C57862D1433":"C6EF9C5D78AE012A011164ACB397CE2088685D8F06BF9BE0B283AB46476BEE53":"D6840F6B42F6EDAFD13116E0E12565202FEF8E9ECE7DCE03812464D04B9442DE":1:0:0:0
+
+ECDH restartable rfc 5903 p256 restart enabled max_ops=1
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecdh_restart:MBEDTLS_ECP_DP_SECP256R1:"C88F01F510D9AC3F70A292DAA2316DE544E9AAB8AFE84049C62A9C57862D1433":"C6EF9C5D78AE012A011164ACB397CE2088685D8F06BF9BE0B283AB46476BEE53":"D6840F6B42F6EDAFD13116E0E12565202FEF8E9ECE7DCE03812464D04B9442DE":1:1:1:10000
+
+ECDH restartable rfc 5903 p256 restart enabled max_ops=10000
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecdh_restart:MBEDTLS_ECP_DP_SECP256R1:"C88F01F510D9AC3F70A292DAA2316DE544E9AAB8AFE84049C62A9C57862D1433":"C6EF9C5D78AE012A011164ACB397CE2088685D8F06BF9BE0B283AB46476BEE53":"D6840F6B42F6EDAFD13116E0E12565202FEF8E9ECE7DCE03812464D04B9442DE":1:10000:0:0
+
+ECDH restartable rfc 5903 p256 restart enabled max_ops=250
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecdh_restart:MBEDTLS_ECP_DP_SECP256R1:"C88F01F510D9AC3F70A292DAA2316DE544E9AAB8AFE84049C62A9C57862D1433":"C6EF9C5D78AE012A011164ACB397CE2088685D8F06BF9BE0B283AB46476BEE53":"D6840F6B42F6EDAFD13116E0E12565202FEF8E9ECE7DCE03812464D04B9442DE":1:250:2:32
+
+ECDH restartable rfc 5903 p256 restart disabled max_ops=0 (disabled)
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecdh_restart:MBEDTLS_ECP_DP_SECP256R1:"C88F01F510D9AC3F70A292DAA2316DE544E9AAB8AFE84049C62A9C57862D1433":"C6EF9C5D78AE012A011164ACB397CE2088685D8F06BF9BE0B283AB46476BEE53":"D6840F6B42F6EDAFD13116E0E12565202FEF8E9ECE7DCE03812464D04B9442DE":0:0:0:0
+
+ECDH restartable rfc 5903 p256 restart disabled max_ops=1
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecdh_restart:MBEDTLS_ECP_DP_SECP256R1:"C88F01F510D9AC3F70A292DAA2316DE544E9AAB8AFE84049C62A9C57862D1433":"C6EF9C5D78AE012A011164ACB397CE2088685D8F06BF9BE0B283AB46476BEE53":"D6840F6B42F6EDAFD13116E0E12565202FEF8E9ECE7DCE03812464D04B9442DE":0:1:0:0
+
+ECDH restartable rfc 5903 p256 restart disabled max_ops=10000
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecdh_restart:MBEDTLS_ECP_DP_SECP256R1:"C88F01F510D9AC3F70A292DAA2316DE544E9AAB8AFE84049C62A9C57862D1433":"C6EF9C5D78AE012A011164ACB397CE2088685D8F06BF9BE0B283AB46476BEE53":"D6840F6B42F6EDAFD13116E0E12565202FEF8E9ECE7DCE03812464D04B9442DE":0:10000:0:0
+
+ECDH restartable rfc 5903 p256 restart disabled max_ops=250
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecdh_restart:MBEDTLS_ECP_DP_SECP256R1:"C88F01F510D9AC3F70A292DAA2316DE544E9AAB8AFE84049C62A9C57862D1433":"C6EF9C5D78AE012A011164ACB397CE2088685D8F06BF9BE0B283AB46476BEE53":"D6840F6B42F6EDAFD13116E0E12565202FEF8E9ECE7DCE03812464D04B9442DE":0:250:0:0
diff --git a/tests/suites/test_suite_ecdh.function b/tests/suites/test_suite_ecdh.function
index 4c6a97b..05e61e4 100644
--- a/tests/suites/test_suite_ecdh.function
+++ b/tests/suites/test_suite_ecdh.function
@@ -158,3 +158,120 @@
     mbedtls_ecdh_free( &cli );
 }
 /* END_CASE */
+
+/* BEGIN_CASE depends_on:MBEDTLS_ECP_RESTARTABLE */
+void ecdh_restart( int id, char *dA_str, char *dB_str, char *z_str,
+                   int enable, int max_ops, int min_restart, int max_restart )
+{
+    int ret;
+    mbedtls_ecdh_context srv, cli;
+    unsigned char buf[1000];
+    const unsigned char *vbuf;
+    size_t len;
+    unsigned char z[MBEDTLS_ECP_MAX_BYTES];
+    size_t z_len;
+    unsigned char rnd_buf_A[MBEDTLS_ECP_MAX_BYTES];
+    unsigned char rnd_buf_B[MBEDTLS_ECP_MAX_BYTES];
+    rnd_buf_info rnd_info_A, rnd_info_B;
+    int cnt_restart;
+
+    mbedtls_ecdh_init( &srv );
+    mbedtls_ecdh_init( &cli );
+
+    z_len = unhexify( z, z_str );
+
+    rnd_info_A.buf = rnd_buf_A;
+    rnd_info_A.length = unhexify( rnd_buf_A, dA_str );
+
+    rnd_info_B.buf = rnd_buf_B;
+    rnd_info_B.length = unhexify( rnd_buf_B, dB_str );
+
+    TEST_ASSERT( mbedtls_ecp_group_load( &srv.grp, id ) == 0 );
+
+    /* otherwise we would have to fix the random buffer,
+     * as in ecdh_primitive_test_vec */
+    TEST_ASSERT( srv.grp.nbits % 8 == 0 );
+
+    /* set up restart parameters */
+    mbedtls_ecp_set_max_ops( max_ops );
+
+    if( enable)
+    {
+        mbedtls_ecdh_enable_restart( &srv );
+        mbedtls_ecdh_enable_restart( &cli );
+    }
+
+    /* server writes its paramaters */
+    memset( buf, 0x00, sizeof( buf ) );
+    len = 0;
+
+    cnt_restart = 0;
+    do {
+        ret = mbedtls_ecdh_make_params( &srv, &len, buf, sizeof( buf ),
+                                        rnd_buffer_rand, &rnd_info_A );
+    } while( ret == MBEDTLS_ERR_ECP_IN_PROGRESS && ++cnt_restart );
+
+    TEST_ASSERT( ret == 0 );
+    TEST_ASSERT( cnt_restart >= min_restart );
+    TEST_ASSERT( cnt_restart <= max_restart );
+
+    /* client read server params */
+    vbuf = buf;
+    TEST_ASSERT( mbedtls_ecdh_read_params( &cli, &vbuf, buf + len ) == 0 );
+
+    /* client writes its key share */
+    memset( buf, 0x00, sizeof( buf ) );
+    len = 0;
+
+    cnt_restart = 0;
+    do {
+        ret = mbedtls_ecdh_make_public( &cli, &len, buf, sizeof( buf ),
+                                        rnd_buffer_rand, &rnd_info_B );
+    } while( ret == MBEDTLS_ERR_ECP_IN_PROGRESS && ++cnt_restart );
+
+    TEST_ASSERT( ret == 0 );
+    TEST_ASSERT( cnt_restart >= min_restart );
+    TEST_ASSERT( cnt_restart <= max_restart );
+
+    /* server reads client key share */
+    TEST_ASSERT( mbedtls_ecdh_read_public( &srv, buf, len ) == 0 );
+
+    /* server computes shared secret */
+    memset( buf, 0, sizeof( buf ) );
+    len = 0;
+
+    cnt_restart = 0;
+    do {
+        ret = mbedtls_ecdh_calc_secret( &srv, &len, buf, sizeof( buf ),
+                                              NULL, NULL );
+    } while( ret == MBEDTLS_ERR_ECP_IN_PROGRESS && ++cnt_restart );
+
+    TEST_ASSERT( ret == 0 );
+    TEST_ASSERT( cnt_restart >= min_restart );
+    TEST_ASSERT( cnt_restart <= max_restart );
+
+    TEST_ASSERT( len == z_len );
+    TEST_ASSERT( memcmp( buf, z, len ) == 0 );
+
+    /* client computes shared secret */
+    memset( buf, 0, sizeof( buf ) );
+    len = 0;
+
+    cnt_restart = 0;
+    do {
+        ret = mbedtls_ecdh_calc_secret( &cli, &len, buf, sizeof( buf ),
+                                              NULL, NULL );
+    } while( ret == MBEDTLS_ERR_ECP_IN_PROGRESS && ++cnt_restart );
+
+    TEST_ASSERT( ret == 0 );
+    TEST_ASSERT( cnt_restart >= min_restart );
+    TEST_ASSERT( cnt_restart <= max_restart );
+
+    TEST_ASSERT( len == z_len );
+    TEST_ASSERT( memcmp( buf, z, len ) == 0 );
+
+exit:
+    mbedtls_ecdh_free( &srv );
+    mbedtls_ecdh_free( &cli );
+}
+/* END_CASE */
diff --git a/tests/suites/test_suite_ecdsa.data b/tests/suites/test_suite_ecdsa.data
index 19c51d3..7e6ec6c 100644
--- a/tests/suites/test_suite_ecdsa.data
+++ b/tests/suites/test_suite_ecdsa.data
@@ -50,7 +50,7 @@
 depends_on:MBEDTLS_ECP_DP_SECP521R1_ENABLED
 ecdsa_write_read_random:MBEDTLS_ECP_DP_SECP521R1
 
-ECDSA deterministic test vector rfc 6979 p192 mbedtls_sha1
+ECDSA deterministic test vector rfc 6979 p192 sha1
 depends_on:MBEDTLS_ECP_DP_SECP192R1_ENABLED:MBEDTLS_SHA1_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP192R1:"6FAB034934E4C0FC9AE67F5B5659A9D7D1FEFD187EE09FD4":MBEDTLS_MD_SHA1:"sample":"98C6BD12B23EAF5E2A2045132086BE3EB8EBD62ABF6698FF":"57A22B07DEA9530F8DE9471B1DC6624472E8E2844BC25B64"
 
@@ -58,7 +58,7 @@
 depends_on:MBEDTLS_ECP_DP_SECP192R1_ENABLED:MBEDTLS_SHA256_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP192R1:"6FAB034934E4C0FC9AE67F5B5659A9D7D1FEFD187EE09FD4":MBEDTLS_MD_SHA224:"sample":"A1F00DAD97AEEC91C95585F36200C65F3C01812AA60378F5":"E07EC1304C7C6C9DEBBE980B9692668F81D4DE7922A0F97A"
 
-ECDSA deterministic test vector rfc 6979 p192 mbedtls_sha256
+ECDSA deterministic test vector rfc 6979 p192 sha256
 depends_on:MBEDTLS_ECP_DP_SECP192R1_ENABLED:MBEDTLS_SHA256_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP192R1:"6FAB034934E4C0FC9AE67F5B5659A9D7D1FEFD187EE09FD4":MBEDTLS_MD_SHA256:"sample":"4B0B8CE98A92866A2820E20AA6B75B56382E0F9BFD5ECB55":"CCDB006926EA9565CBADC840829D8C384E06DE1F1E381B85"
 
@@ -66,11 +66,11 @@
 depends_on:MBEDTLS_ECP_DP_SECP192R1_ENABLED:MBEDTLS_SHA512_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP192R1:"6FAB034934E4C0FC9AE67F5B5659A9D7D1FEFD187EE09FD4":MBEDTLS_MD_SHA384:"sample":"DA63BF0B9ABCF948FBB1E9167F136145F7A20426DCC287D5":"C3AA2C960972BD7A2003A57E1C4C77F0578F8AE95E31EC5E"
 
-ECDSA deterministic test vector rfc 6979 p192 mbedtls_sha512
+ECDSA deterministic test vector rfc 6979 p192 sha512
 depends_on:MBEDTLS_ECP_DP_SECP192R1_ENABLED:MBEDTLS_SHA512_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP192R1:"6FAB034934E4C0FC9AE67F5B5659A9D7D1FEFD187EE09FD4":MBEDTLS_MD_SHA512:"sample":"4D60C5AB1996BD848343B31C00850205E2EA6922DAC2E4B8":"3F6E837448F027A1BF4B34E796E32A811CBB4050908D8F67"
 
-ECDSA deterministic test vector rfc 6979 p192 mbedtls_sha1
+ECDSA deterministic test vector rfc 6979 p192 sha1
 depends_on:MBEDTLS_ECP_DP_SECP192R1_ENABLED:MBEDTLS_SHA1_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP192R1:"6FAB034934E4C0FC9AE67F5B5659A9D7D1FEFD187EE09FD4":MBEDTLS_MD_SHA1:"test":"0F2141A0EBBC44D2E1AF90A50EBCFCE5E197B3B7D4DE036D":"EB18BC9E1F3D7387500CB99CF5F7C157070A8961E38700B7"
 
@@ -78,7 +78,7 @@
 depends_on:MBEDTLS_ECP_DP_SECP192R1_ENABLED:MBEDTLS_SHA256_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP192R1:"6FAB034934E4C0FC9AE67F5B5659A9D7D1FEFD187EE09FD4":MBEDTLS_MD_SHA224:"test":"6945A1C1D1B2206B8145548F633BB61CEF04891BAF26ED34":"B7FB7FDFC339C0B9BD61A9F5A8EAF9BE58FC5CBA2CB15293"
 
-ECDSA deterministic test vector rfc 6979 p192 mbedtls_sha256
+ECDSA deterministic test vector rfc 6979 p192 sha256
 depends_on:MBEDTLS_ECP_DP_SECP192R1_ENABLED:MBEDTLS_SHA256_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP192R1:"6FAB034934E4C0FC9AE67F5B5659A9D7D1FEFD187EE09FD4":MBEDTLS_MD_SHA256:"test":"3A718BD8B4926C3B52EE6BBE67EF79B18CB6EB62B1AD97AE":"5662E6848A4A19B1F1AE2F72ACD4B8BBE50F1EAC65D9124F"
 
@@ -86,11 +86,11 @@
 depends_on:MBEDTLS_ECP_DP_SECP192R1_ENABLED:MBEDTLS_SHA512_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP192R1:"6FAB034934E4C0FC9AE67F5B5659A9D7D1FEFD187EE09FD4":MBEDTLS_MD_SHA384:"test":"B234B60B4DB75A733E19280A7A6034BD6B1EE88AF5332367":"7994090B2D59BB782BE57E74A44C9A1C700413F8ABEFE77A"
 
-ECDSA deterministic test vector rfc 6979 p192 mbedtls_sha512
+ECDSA deterministic test vector rfc 6979 p192 sha512
 depends_on:MBEDTLS_ECP_DP_SECP192R1_ENABLED:MBEDTLS_SHA512_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP192R1:"6FAB034934E4C0FC9AE67F5B5659A9D7D1FEFD187EE09FD4":MBEDTLS_MD_SHA512:"test":"FE4F4AE86A58B6507946715934FE2D8FF9D95B6B098FE739":"74CF5605C98FBA0E1EF34D4B5A1577A7DCF59457CAE52290"
 
-ECDSA deterministic test vector rfc 6979 p224 mbedtls_sha1
+ECDSA deterministic test vector rfc 6979 p224 sha1
 depends_on:MBEDTLS_ECP_DP_SECP224R1_ENABLED:MBEDTLS_SHA1_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP224R1:"F220266E1105BFE3083E03EC7A3A654651F45E37167E88600BF257C1":MBEDTLS_MD_SHA1:"sample":"22226F9D40A96E19C4A301CE5B74B115303C0F3A4FD30FC257FB57AC":"66D1CDD83E3AF75605DD6E2FEFF196D30AA7ED7A2EDF7AF475403D69"
 
@@ -98,7 +98,7 @@
 depends_on:MBEDTLS_ECP_DP_SECP224R1_ENABLED:MBEDTLS_SHA256_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP224R1:"F220266E1105BFE3083E03EC7A3A654651F45E37167E88600BF257C1":MBEDTLS_MD_SHA224:"sample":"1CDFE6662DDE1E4A1EC4CDEDF6A1F5A2FB7FBD9145C12113E6ABFD3E":"A6694FD7718A21053F225D3F46197CA699D45006C06F871808F43EBC"
 
-ECDSA deterministic test vector rfc 6979 p224 mbedtls_sha256
+ECDSA deterministic test vector rfc 6979 p224 sha256
 depends_on:MBEDTLS_ECP_DP_SECP224R1_ENABLED:MBEDTLS_SHA256_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP224R1:"F220266E1105BFE3083E03EC7A3A654651F45E37167E88600BF257C1":MBEDTLS_MD_SHA256:"sample":"61AA3DA010E8E8406C656BC477A7A7189895E7E840CDFE8FF42307BA":"BC814050DAB5D23770879494F9E0A680DC1AF7161991BDE692B10101"
 
@@ -106,11 +106,11 @@
 depends_on:MBEDTLS_ECP_DP_SECP224R1_ENABLED:MBEDTLS_SHA512_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP224R1:"F220266E1105BFE3083E03EC7A3A654651F45E37167E88600BF257C1":MBEDTLS_MD_SHA384:"sample":"0B115E5E36F0F9EC81F1325A5952878D745E19D7BB3EABFABA77E953":"830F34CCDFE826CCFDC81EB4129772E20E122348A2BBD889A1B1AF1D"
 
-ECDSA deterministic test vector rfc 6979 p224 mbedtls_sha512
+ECDSA deterministic test vector rfc 6979 p224 sha512
 depends_on:MBEDTLS_ECP_DP_SECP224R1_ENABLED:MBEDTLS_SHA512_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP224R1:"F220266E1105BFE3083E03EC7A3A654651F45E37167E88600BF257C1":MBEDTLS_MD_SHA512:"sample":"074BD1D979D5F32BF958DDC61E4FB4872ADCAFEB2256497CDAC30397":"A4CECA196C3D5A1FF31027B33185DC8EE43F288B21AB342E5D8EB084"
 
-ECDSA deterministic test vector rfc 6979 p224 mbedtls_sha1
+ECDSA deterministic test vector rfc 6979 p224 sha1
 depends_on:MBEDTLS_ECP_DP_SECP224R1_ENABLED:MBEDTLS_SHA1_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP224R1:"F220266E1105BFE3083E03EC7A3A654651F45E37167E88600BF257C1":MBEDTLS_MD_SHA1:"test":"DEAA646EC2AF2EA8AD53ED66B2E2DDAA49A12EFD8356561451F3E21C":"95987796F6CF2062AB8135271DE56AE55366C045F6D9593F53787BD2"
 
@@ -118,7 +118,7 @@
 depends_on:MBEDTLS_ECP_DP_SECP224R1_ENABLED:MBEDTLS_SHA256_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP224R1:"F220266E1105BFE3083E03EC7A3A654651F45E37167E88600BF257C1":MBEDTLS_MD_SHA224:"test":"C441CE8E261DED634E4CF84910E4C5D1D22C5CF3B732BB204DBEF019":"902F42847A63BDC5F6046ADA114953120F99442D76510150F372A3F4"
 
-ECDSA deterministic test vector rfc 6979 p224 mbedtls_sha256
+ECDSA deterministic test vector rfc 6979 p224 sha256
 depends_on:MBEDTLS_ECP_DP_SECP224R1_ENABLED:MBEDTLS_SHA256_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP224R1:"F220266E1105BFE3083E03EC7A3A654651F45E37167E88600BF257C1":MBEDTLS_MD_SHA256:"test":"AD04DDE87B84747A243A631EA47A1BA6D1FAA059149AD2440DE6FBA6":"178D49B1AE90E3D8B629BE3DB5683915F4E8C99FDF6E666CF37ADCFD"
 
@@ -126,11 +126,11 @@
 depends_on:MBEDTLS_ECP_DP_SECP224R1_ENABLED:MBEDTLS_SHA512_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP224R1:"F220266E1105BFE3083E03EC7A3A654651F45E37167E88600BF257C1":MBEDTLS_MD_SHA384:"test":"389B92682E399B26518A95506B52C03BC9379A9DADF3391A21FB0EA4":"414A718ED3249FF6DBC5B50C27F71F01F070944DA22AB1F78F559AAB"
 
-ECDSA deterministic test vector rfc 6979 p224 mbedtls_sha512
+ECDSA deterministic test vector rfc 6979 p224 sha512
 depends_on:MBEDTLS_ECP_DP_SECP224R1_ENABLED:MBEDTLS_SHA512_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP224R1:"F220266E1105BFE3083E03EC7A3A654651F45E37167E88600BF257C1":MBEDTLS_MD_SHA512:"test":"049F050477C5ADD858CAC56208394B5A55BAEBBE887FDF765047C17C":"077EB13E7005929CEFA3CD0403C7CDCC077ADF4E44F3C41B2F60ECFF"
 
-ECDSA deterministic test vector rfc 6979 p256 mbedtls_sha1
+ECDSA deterministic test vector rfc 6979 p256 sha1
 depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_SHA1_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP256R1:"C9AFA9D845BA75166B5C215767B1D6934E50C3DB36E89B127B8A622B120F6721":MBEDTLS_MD_SHA1:"sample":"61340C88C3AAEBEB4F6D667F672CA9759A6CCAA9FA8811313039EE4A35471D32":"6D7F147DAC089441BB2E2FE8F7A3FA264B9C475098FDCF6E00D7C996E1B8B7EB"
 
@@ -138,7 +138,7 @@
 depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_SHA256_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP256R1:"C9AFA9D845BA75166B5C215767B1D6934E50C3DB36E89B127B8A622B120F6721":MBEDTLS_MD_SHA224:"sample":"53B2FFF5D1752B2C689DF257C04C40A587FABABB3F6FC2702F1343AF7CA9AA3F":"B9AFB64FDC03DC1A131C7D2386D11E349F070AA432A4ACC918BEA988BF75C74C"
 
-ECDSA deterministic test vector rfc 6979 p256 mbedtls_sha256
+ECDSA deterministic test vector rfc 6979 p256 sha256
 depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_SHA256_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP256R1:"C9AFA9D845BA75166B5C215767B1D6934E50C3DB36E89B127B8A622B120F6721":MBEDTLS_MD_SHA256:"sample":"EFD48B2AACB6A8FD1140DD9CD45E81D69D2C877B56AAF991C34D0EA84EAF3716":"F7CB1C942D657C41D436C7A1B6E29F65F3E900DBB9AFF4064DC4AB2F843ACDA8"
 
@@ -146,11 +146,11 @@
 depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_SHA512_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP256R1:"C9AFA9D845BA75166B5C215767B1D6934E50C3DB36E89B127B8A622B120F6721":MBEDTLS_MD_SHA384:"sample":"0EAFEA039B20E9B42309FB1D89E213057CBF973DC0CFC8F129EDDDC800EF7719":"4861F0491E6998B9455193E34E7B0D284DDD7149A74B95B9261F13ABDE940954"
 
-ECDSA deterministic test vector rfc 6979 p256 mbedtls_sha512
+ECDSA deterministic test vector rfc 6979 p256 sha512
 depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_SHA512_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP256R1:"C9AFA9D845BA75166B5C215767B1D6934E50C3DB36E89B127B8A622B120F6721":MBEDTLS_MD_SHA512:"sample":"8496A60B5E9B47C825488827E0495B0E3FA109EC4568FD3F8D1097678EB97F00":"2362AB1ADBE2B8ADF9CB9EDAB740EA6049C028114F2460F96554F61FAE3302FE"
 
-ECDSA deterministic test vector rfc 6979 p256 mbedtls_sha1
+ECDSA deterministic test vector rfc 6979 p256 sha1
 depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_SHA1_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP256R1:"C9AFA9D845BA75166B5C215767B1D6934E50C3DB36E89B127B8A622B120F6721":MBEDTLS_MD_SHA1:"test":"0CBCC86FD6ABD1D99E703E1EC50069EE5C0B4BA4B9AC60E409E8EC5910D81A89":"01B9D7B73DFAA60D5651EC4591A0136F87653E0FD780C3B1BC872FFDEAE479B1"
 
@@ -158,7 +158,7 @@
 depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_SHA256_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP256R1:"C9AFA9D845BA75166B5C215767B1D6934E50C3DB36E89B127B8A622B120F6721":MBEDTLS_MD_SHA224:"test":"C37EDB6F0AE79D47C3C27E962FA269BB4F441770357E114EE511F662EC34A692":"C820053A05791E521FCAAD6042D40AEA1D6B1A540138558F47D0719800E18F2D"
 
-ECDSA deterministic test vector rfc 6979 p256 mbedtls_sha256
+ECDSA deterministic test vector rfc 6979 p256 sha256
 depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_SHA256_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP256R1:"C9AFA9D845BA75166B5C215767B1D6934E50C3DB36E89B127B8A622B120F6721":MBEDTLS_MD_SHA256:"test":"F1ABB023518351CD71D881567B1EA663ED3EFCF6C5132B354F28D3B0B7D38367":"019F4113742A2B14BD25926B49C649155F267E60D3814B4C0CC84250E46F0083"
 
@@ -166,11 +166,11 @@
 depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_SHA512_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP256R1:"C9AFA9D845BA75166B5C215767B1D6934E50C3DB36E89B127B8A622B120F6721":MBEDTLS_MD_SHA384:"test":"83910E8B48BB0C74244EBDF7F07A1C5413D61472BD941EF3920E623FBCCEBEB6":"8DDBEC54CF8CD5874883841D712142A56A8D0F218F5003CB0296B6B509619F2C"
 
-ECDSA deterministic test vector rfc 6979 p256 mbedtls_sha512
+ECDSA deterministic test vector rfc 6979 p256 sha512
 depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_SHA512_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP256R1:"C9AFA9D845BA75166B5C215767B1D6934E50C3DB36E89B127B8A622B120F6721":MBEDTLS_MD_SHA512:"test":"461D93F31B6540894788FD206C07CFA0CC35F46FA3C91816FFF1040AD1581A04":"39AF9F15DE0DB8D97E72719C74820D304CE5226E32DEDAE67519E840D1194E55"
 
-ECDSA deterministic test vector rfc 6979 p384 mbedtls_sha1
+ECDSA deterministic test vector rfc 6979 p384 sha1
 depends_on:MBEDTLS_ECP_DP_SECP384R1_ENABLED:MBEDTLS_SHA1_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP384R1:"6B9D3DAD2E1B8C1C05B19875B6659F4DE23C3B667BF297BA9AA47740787137D896D5724E4C70A825F872C9EA60D2EDF5":MBEDTLS_MD_SHA1:"sample":"EC748D839243D6FBEF4FC5C4859A7DFFD7F3ABDDF72014540C16D73309834FA37B9BA002899F6FDA3A4A9386790D4EB2":"A3BCFA947BEEF4732BF247AC17F71676CB31A847B9FF0CBC9C9ED4C1A5B3FACF26F49CA031D4857570CCB5CA4424A443"
 
@@ -178,7 +178,7 @@
 depends_on:MBEDTLS_ECP_DP_SECP384R1_ENABLED:MBEDTLS_SHA256_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP384R1:"6B9D3DAD2E1B8C1C05B19875B6659F4DE23C3B667BF297BA9AA47740787137D896D5724E4C70A825F872C9EA60D2EDF5":MBEDTLS_MD_SHA224:"sample":"42356E76B55A6D9B4631C865445DBE54E056D3B3431766D0509244793C3F9366450F76EE3DE43F5A125333A6BE060122":"9DA0C81787064021E78DF658F2FBB0B042BF304665DB721F077A4298B095E4834C082C03D83028EFBF93A3C23940CA8D"
 
-ECDSA deterministic test vector rfc 6979 p384 mbedtls_sha256
+ECDSA deterministic test vector rfc 6979 p384 sha256
 depends_on:MBEDTLS_ECP_DP_SECP384R1_ENABLED:MBEDTLS_SHA256_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP384R1:"6B9D3DAD2E1B8C1C05B19875B6659F4DE23C3B667BF297BA9AA47740787137D896D5724E4C70A825F872C9EA60D2EDF5":MBEDTLS_MD_SHA256:"sample":"21B13D1E013C7FA1392D03C5F99AF8B30C570C6F98D4EA8E354B63A21D3DAA33BDE1E888E63355D92FA2B3C36D8FB2CD":"F3AA443FB107745BF4BD77CB3891674632068A10CA67E3D45DB2266FA7D1FEEBEFDC63ECCD1AC42EC0CB8668A4FA0AB0"
 
@@ -186,11 +186,11 @@
 depends_on:MBEDTLS_ECP_DP_SECP384R1_ENABLED:MBEDTLS_SHA512_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP384R1:"6B9D3DAD2E1B8C1C05B19875B6659F4DE23C3B667BF297BA9AA47740787137D896D5724E4C70A825F872C9EA60D2EDF5":MBEDTLS_MD_SHA384:"sample":"94EDBB92A5ECB8AAD4736E56C691916B3F88140666CE9FA73D64C4EA95AD133C81A648152E44ACF96E36DD1E80FABE46":"99EF4AEB15F178CEA1FE40DB2603138F130E740A19624526203B6351D0A3A94FA329C145786E679E7B82C71A38628AC8"
 
-ECDSA deterministic test vector rfc 6979 p384 mbedtls_sha512
+ECDSA deterministic test vector rfc 6979 p384 sha512
 depends_on:MBEDTLS_ECP_DP_SECP384R1_ENABLED:MBEDTLS_SHA512_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP384R1:"6B9D3DAD2E1B8C1C05B19875B6659F4DE23C3B667BF297BA9AA47740787137D896D5724E4C70A825F872C9EA60D2EDF5":MBEDTLS_MD_SHA512:"sample":"ED0959D5880AB2D869AE7F6C2915C6D60F96507F9CB3E047C0046861DA4A799CFE30F35CC900056D7C99CD7882433709":"512C8CCEEE3890A84058CE1E22DBC2198F42323CE8ACA9135329F03C068E5112DC7CC3EF3446DEFCEB01A45C2667FDD5"
 
-ECDSA deterministic test vector rfc 6979 p384 mbedtls_sha1
+ECDSA deterministic test vector rfc 6979 p384 sha1
 depends_on:MBEDTLS_ECP_DP_SECP384R1_ENABLED:MBEDTLS_SHA1_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP384R1:"6B9D3DAD2E1B8C1C05B19875B6659F4DE23C3B667BF297BA9AA47740787137D896D5724E4C70A825F872C9EA60D2EDF5":MBEDTLS_MD_SHA1:"test":"4BC35D3A50EF4E30576F58CD96CE6BF638025EE624004A1F7789A8B8E43D0678ACD9D29876DAF46638645F7F404B11C7":"D5A6326C494ED3FF614703878961C0FDE7B2C278F9A65FD8C4B7186201A2991695BA1C84541327E966FA7B50F7382282"
 
@@ -198,7 +198,7 @@
 depends_on:MBEDTLS_ECP_DP_SECP384R1_ENABLED:MBEDTLS_SHA256_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP384R1:"6B9D3DAD2E1B8C1C05B19875B6659F4DE23C3B667BF297BA9AA47740787137D896D5724E4C70A825F872C9EA60D2EDF5":MBEDTLS_MD_SHA224:"test":"E8C9D0B6EA72A0E7837FEA1D14A1A9557F29FAA45D3E7EE888FC5BF954B5E62464A9A817C47FF78B8C11066B24080E72":"07041D4A7A0379AC7232FF72E6F77B6DDB8F09B16CCE0EC3286B2BD43FA8C6141C53EA5ABEF0D8231077A04540A96B66"
 
-ECDSA deterministic test vector rfc 6979 p384 mbedtls_sha256
+ECDSA deterministic test vector rfc 6979 p384 sha256
 depends_on:MBEDTLS_ECP_DP_SECP384R1_ENABLED:MBEDTLS_SHA256_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP384R1:"6B9D3DAD2E1B8C1C05B19875B6659F4DE23C3B667BF297BA9AA47740787137D896D5724E4C70A825F872C9EA60D2EDF5":MBEDTLS_MD_SHA256:"test":"6D6DEFAC9AB64DABAFE36C6BF510352A4CC27001263638E5B16D9BB51D451559F918EEDAF2293BE5B475CC8F0188636B":"2D46F3BECBCC523D5F1A1256BF0C9B024D879BA9E838144C8BA6BAEB4B53B47D51AB373F9845C0514EEFB14024787265"
 
@@ -206,11 +206,11 @@
 depends_on:MBEDTLS_ECP_DP_SECP384R1_ENABLED:MBEDTLS_SHA512_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP384R1:"6B9D3DAD2E1B8C1C05B19875B6659F4DE23C3B667BF297BA9AA47740787137D896D5724E4C70A825F872C9EA60D2EDF5":MBEDTLS_MD_SHA384:"test":"8203B63D3C853E8D77227FB377BCF7B7B772E97892A80F36AB775D509D7A5FEB0542A7F0812998DA8F1DD3CA3CF023DB":"DDD0760448D42D8A43AF45AF836FCE4DE8BE06B485E9B61B827C2F13173923E06A739F040649A667BF3B828246BAA5A5"
 
-ECDSA deterministic test vector rfc 6979 p384 mbedtls_sha512
+ECDSA deterministic test vector rfc 6979 p384 sha512
 depends_on:MBEDTLS_ECP_DP_SECP384R1_ENABLED:MBEDTLS_SHA512_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP384R1:"6B9D3DAD2E1B8C1C05B19875B6659F4DE23C3B667BF297BA9AA47740787137D896D5724E4C70A825F872C9EA60D2EDF5":MBEDTLS_MD_SHA512:"test":"A0D5D090C9980FAF3C2CE57B7AE951D31977DD11C775D314AF55F76C676447D06FB6495CD21B4B6E340FC236584FB277":"976984E59B4C77B0E8E4460DCA3D9F20E07B9BB1F63BEEFAF576F6B2E8B224634A2092CD3792E0159AD9CEE37659C736"
 
-ECDSA deterministic test vector rfc 6979 p521 mbedtls_sha1
+ECDSA deterministic test vector rfc 6979 p521 sha1
 depends_on:MBEDTLS_ECP_DP_SECP521R1_ENABLED:MBEDTLS_SHA1_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP521R1:"0FAD06DAA62BA3B25D2FB40133DA757205DE67F5BB0018FEE8C86E1B68C7E75CAA896EB32F1F47C70855836A6D16FCC1466F6D8FBEC67DB89EC0C08B0E996B83538":MBEDTLS_MD_SHA1:"sample":"0343B6EC45728975EA5CBA6659BBB6062A5FF89EEA58BE3C80B619F322C87910FE092F7D45BB0F8EEE01ED3F20BABEC079D202AE677B243AB40B5431D497C55D75D":"0E7B0E675A9B24413D448B8CC119D2BF7B2D2DF032741C096634D6D65D0DBE3D5694625FB9E8104D3B842C1B0E2D0B98BEA19341E8676AEF66AE4EBA3D5475D5D16"
 
@@ -218,7 +218,7 @@
 depends_on:MBEDTLS_ECP_DP_SECP521R1_ENABLED:MBEDTLS_SHA256_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP521R1:"0FAD06DAA62BA3B25D2FB40133DA757205DE67F5BB0018FEE8C86E1B68C7E75CAA896EB32F1F47C70855836A6D16FCC1466F6D8FBEC67DB89EC0C08B0E996B83538":MBEDTLS_MD_SHA224:"sample":"1776331CFCDF927D666E032E00CF776187BC9FDD8E69D0DABB4109FFE1B5E2A30715F4CC923A4A5E94D2503E9ACFED92857B7F31D7152E0F8C00C15FF3D87E2ED2E":"050CB5265417FE2320BBB5A122B8E1A32BD699089851128E360E620A30C7E17BA41A666AF126CE100E5799B153B60528D5300D08489CA9178FB610A2006C254B41F"
 
-ECDSA deterministic test vector rfc 6979 p521 mbedtls_sha256
+ECDSA deterministic test vector rfc 6979 p521 sha256
 depends_on:MBEDTLS_ECP_DP_SECP521R1_ENABLED:MBEDTLS_SHA256_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP521R1:"0FAD06DAA62BA3B25D2FB40133DA757205DE67F5BB0018FEE8C86E1B68C7E75CAA896EB32F1F47C70855836A6D16FCC1466F6D8FBEC67DB89EC0C08B0E996B83538":MBEDTLS_MD_SHA256:"sample":"1511BB4D675114FE266FC4372B87682BAECC01D3CC62CF2303C92B3526012659D16876E25C7C1E57648F23B73564D67F61C6F14D527D54972810421E7D87589E1A7":"04A171143A83163D6DF460AAF61522695F207A58B95C0644D87E52AA1A347916E4F7A72930B1BC06DBE22CE3F58264AFD23704CBB63B29B931F7DE6C9D949A7ECFC"
 
@@ -226,11 +226,11 @@
 depends_on:MBEDTLS_ECP_DP_SECP521R1_ENABLED:MBEDTLS_SHA512_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP521R1:"0FAD06DAA62BA3B25D2FB40133DA757205DE67F5BB0018FEE8C86E1B68C7E75CAA896EB32F1F47C70855836A6D16FCC1466F6D8FBEC67DB89EC0C08B0E996B83538":MBEDTLS_MD_SHA384:"sample":"1EA842A0E17D2DE4F92C15315C63DDF72685C18195C2BB95E572B9C5136CA4B4B576AD712A52BE9730627D16054BA40CC0B8D3FF035B12AE75168397F5D50C67451":"1F21A3CEE066E1961025FB048BD5FE2B7924D0CD797BABE0A83B66F1E35EEAF5FDE143FA85DC394A7DEE766523393784484BDF3E00114A1C857CDE1AA203DB65D61"
 
-ECDSA deterministic test vector rfc 6979 p521 mbedtls_sha512
+ECDSA deterministic test vector rfc 6979 p521 sha512
 depends_on:MBEDTLS_ECP_DP_SECP521R1_ENABLED:MBEDTLS_SHA512_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP521R1:"0FAD06DAA62BA3B25D2FB40133DA757205DE67F5BB0018FEE8C86E1B68C7E75CAA896EB32F1F47C70855836A6D16FCC1466F6D8FBEC67DB89EC0C08B0E996B83538":MBEDTLS_MD_SHA512:"sample":"0C328FAFCBD79DD77850370C46325D987CB525569FB63C5D3BC53950E6D4C5F174E25A1EE9017B5D450606ADD152B534931D7D4E8455CC91F9B15BF05EC36E377FA":"0617CCE7CF5064806C467F678D3B4080D6F1CC50AF26CA209417308281B68AF282623EAA63E5B5C0723D8B8C37FF0777B1A20F8CCB1DCCC43997F1EE0E44DA4A67A"
 
-ECDSA deterministic test vector rfc 6979 p521 mbedtls_sha1
+ECDSA deterministic test vector rfc 6979 p521 sha1
 depends_on:MBEDTLS_ECP_DP_SECP521R1_ENABLED:MBEDTLS_SHA1_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP521R1:"0FAD06DAA62BA3B25D2FB40133DA757205DE67F5BB0018FEE8C86E1B68C7E75CAA896EB32F1F47C70855836A6D16FCC1466F6D8FBEC67DB89EC0C08B0E996B83538":MBEDTLS_MD_SHA1:"test":"13BAD9F29ABE20DE37EBEB823C252CA0F63361284015A3BF430A46AAA80B87B0693F0694BD88AFE4E661FC33B094CD3B7963BED5A727ED8BD6A3A202ABE009D0367":"1E9BB81FF7944CA409AD138DBBEE228E1AFCC0C890FC78EC8604639CB0DBDC90F717A99EAD9D272855D00162EE9527567DD6A92CBD629805C0445282BBC916797FF"
 
@@ -238,7 +238,7 @@
 depends_on:MBEDTLS_ECP_DP_SECP521R1_ENABLED:MBEDTLS_SHA256_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP521R1:"0FAD06DAA62BA3B25D2FB40133DA757205DE67F5BB0018FEE8C86E1B68C7E75CAA896EB32F1F47C70855836A6D16FCC1466F6D8FBEC67DB89EC0C08B0E996B83538":MBEDTLS_MD_SHA224:"test":"1C7ED902E123E6815546065A2C4AF977B22AA8EADDB68B2C1110E7EA44D42086BFE4A34B67DDC0E17E96536E358219B23A706C6A6E16BA77B65E1C595D43CAE17FB":"177336676304FCB343CE028B38E7B4FBA76C1C1B277DA18CAD2A8478B2A9A9F5BEC0F3BA04F35DB3E4263569EC6AADE8C92746E4C82F8299AE1B8F1739F8FD519A4"
 
-ECDSA deterministic test vector rfc 6979 p521 mbedtls_sha256
+ECDSA deterministic test vector rfc 6979 p521 sha256
 depends_on:MBEDTLS_ECP_DP_SECP521R1_ENABLED:MBEDTLS_SHA256_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP521R1:"0FAD06DAA62BA3B25D2FB40133DA757205DE67F5BB0018FEE8C86E1B68C7E75CAA896EB32F1F47C70855836A6D16FCC1466F6D8FBEC67DB89EC0C08B0E996B83538":MBEDTLS_MD_SHA256:"test":"00E871C4A14F993C6C7369501900C4BC1E9C7B0B4BA44E04868B30B41D8071042EB28C4C250411D0CE08CD197E4188EA4876F279F90B3D8D74A3C76E6F1E4656AA8":"0CD52DBAA33B063C3A6CD8058A1FB0A46A4754B034FCC644766CA14DA8CA5CA9FDE00E88C1AD60CCBA759025299079D7A427EC3CC5B619BFBC828E7769BCD694E86"
 
@@ -246,10 +246,42 @@
 depends_on:MBEDTLS_ECP_DP_SECP521R1_ENABLED:MBEDTLS_SHA512_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP521R1:"0FAD06DAA62BA3B25D2FB40133DA757205DE67F5BB0018FEE8C86E1B68C7E75CAA896EB32F1F47C70855836A6D16FCC1466F6D8FBEC67DB89EC0C08B0E996B83538":MBEDTLS_MD_SHA384:"test":"14BEE21A18B6D8B3C93FAB08D43E739707953244FDBE924FA926D76669E7AC8C89DF62ED8975C2D8397A65A49DCC09F6B0AC62272741924D479354D74FF6075578C":"133330865C067A0EAF72362A65E2D7BC4E461E8C8995C3B6226A21BD1AA78F0ED94FE536A0DCA35534F0CD1510C41525D163FE9D74D134881E35141ED5E8E95B979"
 
-ECDSA deterministic test vector rfc 6979 p521 mbedtls_sha512
+ECDSA deterministic test vector rfc 6979 p521 sha512
 depends_on:MBEDTLS_ECP_DP_SECP521R1_ENABLED:MBEDTLS_SHA512_C
 ecdsa_det_test_vectors:MBEDTLS_ECP_DP_SECP521R1:"0FAD06DAA62BA3B25D2FB40133DA757205DE67F5BB0018FEE8C86E1B68C7E75CAA896EB32F1F47C70855836A6D16FCC1466F6D8FBEC67DB89EC0C08B0E996B83538":MBEDTLS_MD_SHA512:"test":"13E99020ABF5CEE7525D16B69B229652AB6BDF2AFFCAEF38773B4B7D08725F10CDB93482FDCC54EDCEE91ECA4166B2A7C6265EF0CE2BD7051B7CEF945BABD47EE6D":"1FBD0013C674AA79CB39849527916CE301C66EA7CE8B80682786AD60F98F7E78A19CA69EFF5C57400E3B3A0AD66CE0978214D13BAF4E9AC60752F7B155E2DE4DCE3"
 
+ECDSA restartable read-verify: max_ops=0 (disabled)
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecdsa_read_restart:MBEDTLS_ECP_DP_SECP256R1:"04e8f573412a810c5f81ecd2d251bb94387e72f28af70dced90ebe75725c97a6428231069c2b1ef78509a22c59044319f6ed3cb750dfe64c2a282b35967a458ad6":"dee9d4d8b0e40a034602d6e638197998060f6e9f353ae1d10c94cd56476d3c92":"304502210098a5a1392abe29e4b0a4da3fefe9af0f8c32e5b839ab52ba6a05da9c3b7edd0f0220596f0e195ae1e58c1e53e9e7f0f030b274348a8c11232101778d89c4943f5ad2":0:0:0
+
+ECDSA restartable read-verify: max_ops=1
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecdsa_read_restart:MBEDTLS_ECP_DP_SECP256R1:"04e8f573412a810c5f81ecd2d251bb94387e72f28af70dced90ebe75725c97a6428231069c2b1ef78509a22c59044319f6ed3cb750dfe64c2a282b35967a458ad6":"dee9d4d8b0e40a034602d6e638197998060f6e9f353ae1d10c94cd56476d3c92":"304502210098a5a1392abe29e4b0a4da3fefe9af0f8c32e5b839ab52ba6a05da9c3b7edd0f0220596f0e195ae1e58c1e53e9e7f0f030b274348a8c11232101778d89c4943f5ad2":1:42:10000
+
+ECDSA restartable read-verify: max_ops=10000
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecdsa_read_restart:MBEDTLS_ECP_DP_SECP256R1:"04e8f573412a810c5f81ecd2d251bb94387e72f28af70dced90ebe75725c97a6428231069c2b1ef78509a22c59044319f6ed3cb750dfe64c2a282b35967a458ad6":"dee9d4d8b0e40a034602d6e638197998060f6e9f353ae1d10c94cd56476d3c92":"304502210098a5a1392abe29e4b0a4da3fefe9af0f8c32e5b839ab52ba6a05da9c3b7edd0f0220596f0e195ae1e58c1e53e9e7f0f030b274348a8c11232101778d89c4943f5ad2":10000:0:0
+
+ECDSA restartable read-verify: max_ops=250
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecdsa_read_restart:MBEDTLS_ECP_DP_SECP256R1:"04e8f573412a810c5f81ecd2d251bb94387e72f28af70dced90ebe75725c97a6428231069c2b1ef78509a22c59044319f6ed3cb750dfe64c2a282b35967a458ad6":"dee9d4d8b0e40a034602d6e638197998060f6e9f353ae1d10c94cd56476d3c92":"304502210098a5a1392abe29e4b0a4da3fefe9af0f8c32e5b839ab52ba6a05da9c3b7edd0f0220596f0e195ae1e58c1e53e9e7f0f030b274348a8c11232101778d89c4943f5ad2":250:4:64
+
+ECDSA restartable sign-write: secp256r1 max_ops=0 (disabled)
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_SHA256_C
+ecdsa_write_restart:MBEDTLS_ECP_DP_SECP256R1:"C9AFA9D845BA75166B5C215767B1D6934E50C3DB36E89B127B8A622B120F6721":MBEDTLS_MD_SHA256:"test":"3045022100f1abb023518351cd71d881567b1ea663ed3efcf6c5132b354f28d3b0b7d383670220019f4113742a2b14bd25926b49c649155f267e60d3814b4c0cc84250e46f0083":0:0:0
+
+ECDSA restartable sign-write: secp256r1 restart max_ops=1
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_SHA256_C
+ecdsa_write_restart:MBEDTLS_ECP_DP_SECP256R1:"C9AFA9D845BA75166B5C215767B1D6934E50C3DB36E89B127B8A622B120F6721":MBEDTLS_MD_SHA256:"test":"3045022100f1abb023518351cd71d881567b1ea663ed3efcf6c5132b354f28d3b0b7d383670220019f4113742a2b14bd25926b49c649155f267e60d3814b4c0cc84250e46f0083":1:1:10000
+
+ECDSA restartable sign-write: secp256r1 restart max_ops=10000
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_SHA256_C
+ecdsa_write_restart:MBEDTLS_ECP_DP_SECP256R1:"C9AFA9D845BA75166B5C215767B1D6934E50C3DB36E89B127B8A622B120F6721":MBEDTLS_MD_SHA256:"test":"3045022100f1abb023518351cd71d881567b1ea663ed3efcf6c5132b354f28d3b0b7d383670220019f4113742a2b14bd25926b49c649155f267e60d3814b4c0cc84250e46f0083":10000:0:0
+
+ECDSA restartable sign-write: secp256r1 restart max_ops=250
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_SHA256_C
+ecdsa_write_restart:MBEDTLS_ECP_DP_SECP256R1:"C9AFA9D845BA75166B5C215767B1D6934E50C3DB36E89B127B8A622B120F6721":MBEDTLS_MD_SHA256:"test":"3045022100f1abb023518351cd71d881567b1ea663ed3efcf6c5132b354f28d3b0b7d383670220019f4113742a2b14bd25926b49c649155f267e60d3814b4c0cc84250e46f0083":250:2:32
+
 ECDSA zero private parameter p192
 depends_on:MBEDTLS_ECP_DP_SECP192R1_ENABLED
 ecdsa_prim_test_vectors:MBEDTLS_ECP_DP_SECP192R1:"0":"2442A5CC0ECD015FA3CA31DC8E2BBC70BF42D60CBCA20085":"6FC98BD7E50211A4A27102FA3549DF79EBCB4BF246B80945":"9E56F509196784D963D1C0A401510EE7ADA3DCC5DEE04B15":"BA7816BF8F01CFEA414140DE5DAE2223B00361A396177A9C":"98C6BD12B23EAF5E2A2045132086BE3EB8EBD62ABF6698FF":"57A22B07DEA9530F8DE9471B1DC6624472E8E2844BC25B64":MBEDTLS_ERR_ECP_INVALID_KEY
diff --git a/tests/suites/test_suite_ecdsa.function b/tests/suites/test_suite_ecdsa.function
index b730953..4e4ee6d 100644
--- a/tests/suites/test_suite_ecdsa.function
+++ b/tests/suites/test_suite_ecdsa.function
@@ -90,6 +90,16 @@
         TEST_ASSERT( mbedtls_ecdsa_verify( &grp, hash, hlen, &Q, &r_check, &s_check ) == 0 );
     }
 
+    TEST_ASSERT( mbedtls_mpi_sub_int( &r, &r, 1 ) == 0 );
+    TEST_ASSERT( mbedtls_mpi_add_int( &s, &s, 1 ) == 0 );
+
+    TEST_ASSERT( mbedtls_ecdsa_verify( &grp, hash, hlen,
+                 &Q, &r, &s_check ) == MBEDTLS_ERR_ECP_VERIFY_FAILED );
+    TEST_ASSERT( mbedtls_ecdsa_verify( &grp, hash, hlen,
+                 &Q, &r_check, &s ) == MBEDTLS_ERR_ECP_VERIFY_FAILED );
+    TEST_ASSERT( mbedtls_ecdsa_verify( &grp, hash, hlen,
+                 &grp.G, &r_check, &s_check ) == MBEDTLS_ERR_ECP_VERIFY_FAILED );
+
 exit:
     mbedtls_ecp_group_free( &grp );
     mbedtls_ecp_point_free( &Q );
@@ -181,13 +191,13 @@
     /* try modifying r */
     sig[10]++;
     TEST_ASSERT( mbedtls_ecdsa_read_signature( &ctx, hash, sizeof( hash ),
-                 sig, sig_len ) != 0 );
+                 sig, sig_len ) == MBEDTLS_ERR_ECP_VERIFY_FAILED );
     sig[10]--;
 
     /* try modifying s */
     sig[sig_len - 1]++;
     TEST_ASSERT( mbedtls_ecdsa_read_signature( &ctx, hash, sizeof( hash ),
-                 sig, sig_len ) != 0 );
+                 sig, sig_len ) == MBEDTLS_ERR_ECP_VERIFY_FAILED );
     sig[sig_len - 1]--;
 
 exit:
@@ -195,3 +205,130 @@
 }
 /* END_CASE */
 
+/* BEGIN_CASE depends_on:MBEDTLS_ECP_RESTARTABLE */
+void ecdsa_read_restart( int id, char *k_str, char *h_str, char *s_str,
+                         int max_ops, int min_restart, int max_restart )
+{
+    mbedtls_ecdsa_context ctx;
+    mbedtls_ecdsa_restart_ctx rs_ctx;
+    unsigned char hash[64];
+    unsigned char sig[200];
+    unsigned char pk[65];
+    size_t sig_len, hash_len, pk_len;
+    int ret, cnt_restart;
+
+    mbedtls_ecdsa_init( &ctx );
+    mbedtls_ecdsa_restart_init( &rs_ctx );
+
+    hash_len = unhexify(hash, h_str);
+    sig_len = unhexify(sig, s_str);
+    pk_len = unhexify(pk, k_str);
+
+    TEST_ASSERT( mbedtls_ecp_group_load( &ctx.grp, id ) == 0 );
+    TEST_ASSERT( mbedtls_ecp_point_read_binary( &ctx.grp, &ctx.Q, pk, pk_len ) == 0 );
+
+    mbedtls_ecp_set_max_ops( max_ops );
+
+    cnt_restart = 0;
+    do {
+        ret = mbedtls_ecdsa_read_signature_restartable( &ctx,
+                            hash, hash_len, sig, sig_len, &rs_ctx );
+    } while( ret == MBEDTLS_ERR_ECP_IN_PROGRESS && ++cnt_restart );
+
+    TEST_ASSERT( ret == 0 );
+    TEST_ASSERT( cnt_restart >= min_restart );
+    TEST_ASSERT( cnt_restart <= max_restart );
+
+    /* try modifying r */
+    sig[10]++;
+    do {
+        ret = mbedtls_ecdsa_read_signature_restartable( &ctx,
+                            hash, hash_len, sig, sig_len, &rs_ctx );
+    } while( ret == MBEDTLS_ERR_ECP_IN_PROGRESS );
+    TEST_ASSERT( ret == MBEDTLS_ERR_ECP_VERIFY_FAILED );
+    sig[10]--;
+
+    /* try modifying s */
+    sig[sig_len - 1]++;
+    do {
+        ret = mbedtls_ecdsa_read_signature_restartable( &ctx,
+                            hash, hash_len, sig, sig_len, &rs_ctx );
+    } while( ret == MBEDTLS_ERR_ECP_IN_PROGRESS );
+    TEST_ASSERT( ret == MBEDTLS_ERR_ECP_VERIFY_FAILED );
+    sig[sig_len - 1]--;
+
+    /* Do we leak memory when aborting an operation?
+     * This test only makes sense when we actually restart */
+    if( min_restart > 0 )
+    {
+        ret = mbedtls_ecdsa_read_signature_restartable( &ctx,
+                            hash, hash_len, sig, sig_len, &rs_ctx );
+        TEST_ASSERT( ret == MBEDTLS_ERR_ECP_IN_PROGRESS );
+    }
+
+exit:
+    mbedtls_ecdsa_free( &ctx );
+    mbedtls_ecdsa_restart_free( &rs_ctx );
+}
+/* END_CASE */
+
+/* BEGIN_CASE depends_on:MBEDTLS_ECP_RESTARTABLE:MBEDTLS_ECDSA_DETERMINISTIC */
+void ecdsa_write_restart( int id, char *d_str, int md_alg,
+                          char *msg, char *sig_str,
+                          int max_ops, int min_restart, int max_restart )
+{
+    int ret, cnt_restart;
+    mbedtls_ecdsa_restart_ctx rs_ctx;
+    mbedtls_ecdsa_context ctx;
+    unsigned char hash[MBEDTLS_MD_MAX_SIZE];
+    unsigned char sig[MBEDTLS_ECDSA_MAX_LEN];
+    unsigned char sig_check[MBEDTLS_ECDSA_MAX_LEN];
+    size_t hlen, slen, slen_check;
+    const mbedtls_md_info_t *md_info;
+
+    mbedtls_ecdsa_restart_init( &rs_ctx );
+    mbedtls_ecdsa_init( &ctx );
+    memset( hash, 0, sizeof( hash ) );
+    memset( sig, 0, sizeof( sig ) );
+    memset( sig_check, 0, sizeof( sig_check ) );
+
+    TEST_ASSERT( mbedtls_ecp_group_load( &ctx.grp, id ) == 0 );
+    TEST_ASSERT( mbedtls_mpi_read_string( &ctx.d, 16, d_str ) == 0 );
+    slen_check = unhexify( sig_check, sig_str );
+
+    md_info = mbedtls_md_info_from_type( md_alg );
+    TEST_ASSERT( md_info != NULL );
+
+    hlen = mbedtls_md_get_size( md_info );
+    mbedtls_md( md_info, (const unsigned char *) msg, strlen( msg ), hash );
+
+    mbedtls_ecp_set_max_ops( max_ops );
+
+    slen = sizeof( sig );
+    cnt_restart = 0;
+    do {
+        ret = mbedtls_ecdsa_write_signature_restartable( &ctx,
+                md_alg, hash, hlen, sig, &slen, NULL, NULL, &rs_ctx );
+    } while( ret == MBEDTLS_ERR_ECP_IN_PROGRESS && ++cnt_restart );
+
+    TEST_ASSERT( ret == 0 );
+    TEST_ASSERT( slen == slen_check );
+    TEST_ASSERT( memcmp( sig, sig_check, slen ) == 0 );
+
+    TEST_ASSERT( cnt_restart >= min_restart );
+    TEST_ASSERT( cnt_restart <= max_restart );
+
+    /* Do we leak memory when aborting an operation?
+     * This test only makes sense when we actually restart */
+    if( min_restart > 0 )
+    {
+        ret = mbedtls_ecdsa_write_signature_restartable( &ctx,
+                md_alg, hash, hlen, sig, &slen, NULL, NULL, &rs_ctx );
+        TEST_ASSERT( ret == MBEDTLS_ERR_ECP_IN_PROGRESS );
+    }
+
+exit:
+    mbedtls_ecdsa_restart_free( &rs_ctx );
+    mbedtls_ecdsa_free( &ctx );
+}
+/* END_CASE */
diff --git a/tests/suites/test_suite_ecp.data b/tests/suites/test_suite_ecp.data
index 8e9d9fa..b3f992d 100644
--- a/tests/suites/test_suite_ecp.data
+++ b/tests/suites/test_suite_ecp.data
@@ -348,3 +348,35 @@
 
 ECP selftest
 ecp_selftest:
+
+ECP restartable mul secp256r1 max_ops=0 (disabled)
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecp_test_vect_restart:MBEDTLS_ECP_DP_SECP256R1:"814264145F2F56F2E96A8E337A1284993FAF432A5ABCE59E867B7291D507A3AF":"2AF502F3BE8952F2C9B5A8D4160D09E97165BE50BC42AE4A5E8D3B4BA83AEB15":"EB0FAF4CA986C4D38681A0F9872D79D56795BD4BFF6E6DE3C0F5015ECE5EFD85":"2CE1788EC197E096DB95A200CC0AB26A19CE6BCCAD562B8EEE1B593761CF7F41":"DD0F5396219D1EA393310412D19A08F1F5811E9DC8EC8EEA7F80D21C820C2788":"0357DCCD4C804D0D8D33AA42B848834AA5605F9AB0D37239A115BBB647936F50":0:0:0
+
+ECP restartable mul secp256r1 max_ops=1
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecp_test_vect_restart:MBEDTLS_ECP_DP_SECP256R1:"814264145F2F56F2E96A8E337A1284993FAF432A5ABCE59E867B7291D507A3AF":"2AF502F3BE8952F2C9B5A8D4160D09E97165BE50BC42AE4A5E8D3B4BA83AEB15":"EB0FAF4CA986C4D38681A0F9872D79D56795BD4BFF6E6DE3C0F5015ECE5EFD85":"2CE1788EC197E096DB95A200CC0AB26A19CE6BCCAD562B8EEE1B593761CF7F41":"DD0F5396219D1EA393310412D19A08F1F5811E9DC8EC8EEA7F80D21C820C2788":"0357DCCD4C804D0D8D33AA42B848834AA5605F9AB0D37239A115BBB647936F50":1:1:5000
+
+ECP restartable mul secp256r1 max_ops=10000
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecp_test_vect_restart:MBEDTLS_ECP_DP_SECP256R1:"814264145F2F56F2E96A8E337A1284993FAF432A5ABCE59E867B7291D507A3AF":"2AF502F3BE8952F2C9B5A8D4160D09E97165BE50BC42AE4A5E8D3B4BA83AEB15":"EB0FAF4CA986C4D38681A0F9872D79D56795BD4BFF6E6DE3C0F5015ECE5EFD85":"2CE1788EC197E096DB95A200CC0AB26A19CE6BCCAD562B8EEE1B593761CF7F41":"DD0F5396219D1EA393310412D19A08F1F5811E9DC8EC8EEA7F80D21C820C2788":"0357DCCD4C804D0D8D33AA42B848834AA5605F9AB0D37239A115BBB647936F50":10000:0:0
+
+ECP restartable mul secp256r1 max_ops=250
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecp_test_vect_restart:MBEDTLS_ECP_DP_SECP256R1:"814264145F2F56F2E96A8E337A1284993FAF432A5ABCE59E867B7291D507A3AF":"2AF502F3BE8952F2C9B5A8D4160D09E97165BE50BC42AE4A5E8D3B4BA83AEB15":"EB0FAF4CA986C4D38681A0F9872D79D56795BD4BFF6E6DE3C0F5015ECE5EFD85":"2CE1788EC197E096DB95A200CC0AB26A19CE6BCCAD562B8EEE1B593761CF7F41":"DD0F5396219D1EA393310412D19A08F1F5811E9DC8EC8EEA7F80D21C820C2788":"0357DCCD4C804D0D8D33AA42B848834AA5605F9AB0D37239A115BBB647936F50":250:2:32
+
+ECP restartable muladd secp256r1 max_ops=0 (disabled)
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecp_muladd_restart:MBEDTLS_ECP_DP_SECP256R1:"CB28E0999B9C7715FD0A80D8E47A77079716CBBF917DD72E97566EA1C066957C":"2B57C0235FB7489768D058FF4911C20FDBE71E3699D91339AFBB903EE17255DC":"C3875E57C85038A0D60370A87505200DC8317C8C534948BEA6559C7C18E6D4CE":"3B4E49C4FDBFC006FF993C81A50EAE221149076D6EC09DDD9FB3B787F85B6483":"2442A5CC0ECD015FA3CA31DC8E2BBC70BF42D60CBCA20085E0822CB04235E970":"6FC98BD7E50211A4A27102FA3549DF79EBCB4BF246B80945CDDFE7D509BBFD7D":0:0:0
+
+ECP restartable muladd secp256r1 max_ops=1
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecp_muladd_restart:MBEDTLS_ECP_DP_SECP256R1:"CB28E0999B9C7715FD0A80D8E47A77079716CBBF917DD72E97566EA1C066957C":"2B57C0235FB7489768D058FF4911C20FDBE71E3699D91339AFBB903EE17255DC":"C3875E57C85038A0D60370A87505200DC8317C8C534948BEA6559C7C18E6D4CE":"3B4E49C4FDBFC006FF993C81A50EAE221149076D6EC09DDD9FB3B787F85B6483":"2442A5CC0ECD015FA3CA31DC8E2BBC70BF42D60CBCA20085E0822CB04235E970":"6FC98BD7E50211A4A27102FA3549DF79EBCB4BF246B80945CDDFE7D509BBFD7D":1:1:10000
+
+ECP restartable muladd secp256r1 max_ops=10000
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecp_muladd_restart:MBEDTLS_ECP_DP_SECP256R1:"CB28E0999B9C7715FD0A80D8E47A77079716CBBF917DD72E97566EA1C066957C":"2B57C0235FB7489768D058FF4911C20FDBE71E3699D91339AFBB903EE17255DC":"C3875E57C85038A0D60370A87505200DC8317C8C534948BEA6559C7C18E6D4CE":"3B4E49C4FDBFC006FF993C81A50EAE221149076D6EC09DDD9FB3B787F85B6483":"2442A5CC0ECD015FA3CA31DC8E2BBC70BF42D60CBCA20085E0822CB04235E970":"6FC98BD7E50211A4A27102FA3549DF79EBCB4BF246B80945CDDFE7D509BBFD7D":10000:0:0
+
+ECP restartable muladd secp256r1 max_ops=250
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecp_muladd_restart:MBEDTLS_ECP_DP_SECP256R1:"CB28E0999B9C7715FD0A80D8E47A77079716CBBF917DD72E97566EA1C066957C":"2B57C0235FB7489768D058FF4911C20FDBE71E3699D91339AFBB903EE17255DC":"C3875E57C85038A0D60370A87505200DC8317C8C534948BEA6559C7C18E6D4CE":"3B4E49C4FDBFC006FF993C81A50EAE221149076D6EC09DDD9FB3B787F85B6483":"2442A5CC0ECD015FA3CA31DC8E2BBC70BF42D60CBCA20085E0822CB04235E970":"6FC98BD7E50211A4A27102FA3549DF79EBCB4BF246B80945CDDFE7D509BBFD7D":250:4:64
diff --git a/tests/suites/test_suite_ecp.function b/tests/suites/test_suite_ecp.function
index 99780c0..c60d0d3 100644
--- a/tests/suites/test_suite_ecp.function
+++ b/tests/suites/test_suite_ecp.function
@@ -51,6 +51,167 @@
 }
 /* END_CASE */
 
+/* BEGIN_CASE depends_on:MBEDTLS_ECP_RESTARTABLE */
+void ecp_test_vect_restart( int id,
+                            char *dA_str, char *xA_str, char *yA_str,
+                            char *dB_str,  char *xZ_str, char *yZ_str,
+                            int max_ops, int min_restarts, int max_restarts )
+{
+    /*
+     * Test for early restart. Based on test vectors like ecp_test_vect(),
+     * but for the sake of simplicity only does half of each side. It's
+     * important to test both base point and random point, though, as memory
+     * management is different in each case.
+     *
+     * Don't try using too precise bounds for restarts as the exact number
+     * will depend on settings such as MBEDTLS_ECP_FIXED_POINT_OPTIM and
+     * MBEDTLS_ECP_WINDOW_SIZE, as well as implementation details that may
+     * change in the future. A factor 2 is a minimum safety margin.
+     *
+     * For reference, with mbed TLS 2.4 and default settings, for P-256:
+     * - Random point mult:     ~3250M
+     * - Cold base point mult:  ~3300M
+     * - Hot base point mult:   ~1100M
+     * With MBEDTLS_ECP_WINDOW_SIZE set to 2 (minimum):
+     * - Random point mult:     ~3850M
+     */
+    mbedtls_ecp_restart_ctx ctx;
+    mbedtls_ecp_group grp;
+    mbedtls_ecp_point R;
+    mbedtls_mpi dA, xA, yA, dB, xZ, yZ;
+    int cnt_restarts;
+    int ret;
+
+    mbedtls_ecp_restart_init( &ctx );
+    mbedtls_ecp_group_init( &grp ); mbedtls_ecp_point_init( &R );
+    mbedtls_mpi_init( &dA ); mbedtls_mpi_init( &xA ); mbedtls_mpi_init( &yA );
+    mbedtls_mpi_init( &dB ); mbedtls_mpi_init( &xZ ); mbedtls_mpi_init( &yZ );
+
+    TEST_ASSERT( mbedtls_ecp_group_load( &grp, id ) == 0 );
+
+    TEST_ASSERT( mbedtls_mpi_read_string( &dA, 16, dA_str ) == 0 );
+    TEST_ASSERT( mbedtls_mpi_read_string( &xA, 16, xA_str ) == 0 );
+    TEST_ASSERT( mbedtls_mpi_read_string( &yA, 16, yA_str ) == 0 );
+
+    TEST_ASSERT( mbedtls_mpi_read_string( &dB, 16, dB_str ) == 0 );
+    TEST_ASSERT( mbedtls_mpi_read_string( &xZ, 16, xZ_str ) == 0 );
+    TEST_ASSERT( mbedtls_mpi_read_string( &yZ, 16, yZ_str ) == 0 );
+
+    mbedtls_ecp_set_max_ops( (unsigned) max_ops );
+
+    /* Base point case */
+    cnt_restarts = 0;
+    do {
+        ret = mbedtls_ecp_mul_restartable( &grp, &R, &dA, &grp.G, NULL, NULL, &ctx );
+    } while( ret == MBEDTLS_ERR_ECP_IN_PROGRESS && ++cnt_restarts );
+
+    TEST_ASSERT( ret == 0 );
+    TEST_ASSERT( mbedtls_mpi_cmp_mpi( &R.X, &xA ) == 0 );
+    TEST_ASSERT( mbedtls_mpi_cmp_mpi( &R.Y, &yA ) == 0 );
+
+    TEST_ASSERT( cnt_restarts >= min_restarts );
+    TEST_ASSERT( cnt_restarts <= max_restarts );
+
+    /* Non-base point case */
+    cnt_restarts = 0;
+    do {
+        ret = mbedtls_ecp_mul_restartable( &grp, &R, &dB, &R, NULL, NULL, &ctx );
+    } while( ret == MBEDTLS_ERR_ECP_IN_PROGRESS && ++cnt_restarts );
+
+    TEST_ASSERT( ret == 0 );
+    TEST_ASSERT( mbedtls_mpi_cmp_mpi( &R.X, &xZ ) == 0 );
+    TEST_ASSERT( mbedtls_mpi_cmp_mpi( &R.Y, &yZ ) == 0 );
+
+    TEST_ASSERT( cnt_restarts >= min_restarts );
+    TEST_ASSERT( cnt_restarts <= max_restarts );
+
+    /* Do we leak memory when aborting an operation?
+     * This test only makes sense when we actually restart */
+    if( min_restarts > 0 )
+    {
+        ret = mbedtls_ecp_mul_restartable( &grp, &R, &dB, &R, NULL, NULL, &ctx );
+        TEST_ASSERT( ret == MBEDTLS_ERR_ECP_IN_PROGRESS );
+    }
+
+exit:
+    mbedtls_ecp_restart_free( &ctx );
+    mbedtls_ecp_group_free( &grp ); mbedtls_ecp_point_free( &R );
+    mbedtls_mpi_free( &dA ); mbedtls_mpi_free( &xA ); mbedtls_mpi_free( &yA );
+    mbedtls_mpi_free( &dB ); mbedtls_mpi_free( &xZ ); mbedtls_mpi_free( &yZ );
+}
+/* END_CASE */
+
+/* BEGIN_CASE depends_on:MBEDTLS_ECP_RESTARTABLE */
+void ecp_muladd_restart( int id, char *xR_str, char *yR_str,
+                         char *u1_str, char *u2_str,
+                         char *xQ_str, char *yQ_str,
+                         int max_ops, int min_restarts, int max_restarts )
+{
+    /*
+     * Compute R = u1 * G + u2 * Q
+     * (test vectors mostly taken from ECDSA intermediate results)
+     *
+     * See comments at the top of ecp_test_vect_restart()
+     */
+    mbedtls_ecp_restart_ctx ctx;
+    mbedtls_ecp_group grp;
+    mbedtls_ecp_point R, Q;
+    mbedtls_mpi u1, u2, xR, yR;
+    int cnt_restarts;
+    int ret;
+
+    mbedtls_ecp_restart_init( &ctx );
+    mbedtls_ecp_group_init( &grp );
+    mbedtls_ecp_point_init( &R );
+    mbedtls_ecp_point_init( &Q );
+    mbedtls_mpi_init( &u1 ); mbedtls_mpi_init( &u2 );
+    mbedtls_mpi_init( &xR ); mbedtls_mpi_init( &yR );
+
+    TEST_ASSERT( mbedtls_ecp_group_load( &grp, id ) == 0 );
+
+    TEST_ASSERT( mbedtls_mpi_read_string( &u1, 16, u1_str ) == 0 );
+    TEST_ASSERT( mbedtls_mpi_read_string( &u2, 16, u2_str ) == 0 );
+    TEST_ASSERT( mbedtls_mpi_read_string( &xR, 16, xR_str ) == 0 );
+    TEST_ASSERT( mbedtls_mpi_read_string( &yR, 16, yR_str ) == 0 );
+
+    TEST_ASSERT( mbedtls_mpi_read_string( &Q.X, 16, xQ_str ) == 0 );
+    TEST_ASSERT( mbedtls_mpi_read_string( &Q.Y, 16, yQ_str ) == 0 );
+    TEST_ASSERT( mbedtls_mpi_lset( &Q.Z, 1 ) == 0 );
+
+    mbedtls_ecp_set_max_ops( (unsigned) max_ops );
+
+    cnt_restarts = 0;
+    do {
+        ret = mbedtls_ecp_muladd_restartable( &grp, &R,
+                                              &u1, &grp.G, &u2, &Q, &ctx );
+    } while( ret == MBEDTLS_ERR_ECP_IN_PROGRESS && ++cnt_restarts );
+
+    TEST_ASSERT( ret == 0 );
+    TEST_ASSERT( mbedtls_mpi_cmp_mpi( &R.X, &xR ) == 0 );
+    TEST_ASSERT( mbedtls_mpi_cmp_mpi( &R.Y, &yR ) == 0 );
+
+    TEST_ASSERT( cnt_restarts >= min_restarts );
+    TEST_ASSERT( cnt_restarts <= max_restarts );
+
+    /* Do we leak memory when aborting an operation?
+     * This test only makes sense when we actually restart */
+    if( min_restarts > 0 )
+    {
+        ret = mbedtls_ecp_muladd_restartable( &grp, &R,
+                                              &u1, &grp.G, &u2, &Q, &ctx );
+        TEST_ASSERT( ret == MBEDTLS_ERR_ECP_IN_PROGRESS );
+    }
+
+exit:
+    mbedtls_ecp_restart_free( &ctx );
+    mbedtls_ecp_group_free( &grp );
+    mbedtls_ecp_point_free( &R );
+    mbedtls_ecp_point_free( &Q );
+    mbedtls_mpi_free( &u1 ); mbedtls_mpi_free( &u2 );
+    mbedtls_mpi_free( &xR ); mbedtls_mpi_free( &yR );
+}
+/* END_CASE */
+
 /* BEGIN_CASE */
 void ecp_test_vect( int id, char *dA_str, char *xA_str, char *yA_str,
                     char *dB_str, char *xB_str, char *yB_str, char *xZ_str,
diff --git a/tests/suites/test_suite_pk.data b/tests/suites/test_suite_pk.data
index a066bd9..478cde7 100644
--- a/tests/suites/test_suite_pk.data
+++ b/tests/suites/test_suite_pk.data
@@ -153,3 +153,35 @@
 RSA hash_len overflow (size_t vs unsigned int)
 depends_on:MBEDTLS_RSA_C:MBEDTLS_HAVE_INT64
 pk_rsa_overflow:
+
+ECDSA restartable sign/verify: ECDSA, max_ops=0 (disabled)
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_SHA256_C
+pk_sign_verify_restart:MBEDTLS_PK_ECDSA:MBEDTLS_ECP_DP_SECP256R1:"C9AFA9D845BA75166B5C215767B1D6934E50C3DB36E89B127B8A622B120F6721":"60FED4BA255A9D31C961EB74C6356D68C049B8923B61FA6CE669622E60F29FB6":"7903FE1008B8BC99A41AE9E95628BC64F2F1B20C2D7E9F5177A3C294D4462299":MBEDTLS_MD_SHA256:"test":"3045022100f1abb023518351cd71d881567b1ea663ed3efcf6c5132b354f28d3b0b7d383670220019f4113742a2b14bd25926b49c649155f267e60d3814b4c0cc84250e46f0083":0:0:0
+
+ECDSA restartable sign/verify: ECKEY, max_ops=0 (disabled)
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_SHA256_C
+pk_sign_verify_restart:MBEDTLS_PK_ECKEY:MBEDTLS_ECP_DP_SECP256R1:"C9AFA9D845BA75166B5C215767B1D6934E50C3DB36E89B127B8A622B120F6721":"60FED4BA255A9D31C961EB74C6356D68C049B8923B61FA6CE669622E60F29FB6":"7903FE1008B8BC99A41AE9E95628BC64F2F1B20C2D7E9F5177A3C294D4462299":MBEDTLS_MD_SHA256:"test":"3045022100f1abb023518351cd71d881567b1ea663ed3efcf6c5132b354f28d3b0b7d383670220019f4113742a2b14bd25926b49c649155f267e60d3814b4c0cc84250e46f0083":0:0:0
+
+ECDSA restartable sign/verify: ECDSA, max_ops=1
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_SHA256_C
+pk_sign_verify_restart:MBEDTLS_PK_ECDSA:MBEDTLS_ECP_DP_SECP256R1:"C9AFA9D845BA75166B5C215767B1D6934E50C3DB36E89B127B8A622B120F6721":"60FED4BA255A9D31C961EB74C6356D68C049B8923B61FA6CE669622E60F29FB6":"7903FE1008B8BC99A41AE9E95628BC64F2F1B20C2D7E9F5177A3C294D4462299":MBEDTLS_MD_SHA256:"test":"3045022100f1abb023518351cd71d881567b1ea663ed3efcf6c5132b354f28d3b0b7d383670220019f4113742a2b14bd25926b49c649155f267e60d3814b4c0cc84250e46f0083":1:1:10000
+
+ECDSA restartable sign/verify: ECKEY, max_ops=1
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_SHA256_C
+pk_sign_verify_restart:MBEDTLS_PK_ECKEY:MBEDTLS_ECP_DP_SECP256R1:"C9AFA9D845BA75166B5C215767B1D6934E50C3DB36E89B127B8A622B120F6721":"60FED4BA255A9D31C961EB74C6356D68C049B8923B61FA6CE669622E60F29FB6":"7903FE1008B8BC99A41AE9E95628BC64F2F1B20C2D7E9F5177A3C294D4462299":MBEDTLS_MD_SHA256:"test":"3045022100f1abb023518351cd71d881567b1ea663ed3efcf6c5132b354f28d3b0b7d383670220019f4113742a2b14bd25926b49c649155f267e60d3814b4c0cc84250e46f0083":1:1:10000
+
+ECDSA restartable sign/verify: ECDSA, max_ops=10000
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_SHA256_C
+pk_sign_verify_restart:MBEDTLS_PK_ECDSA:MBEDTLS_ECP_DP_SECP256R1:"C9AFA9D845BA75166B5C215767B1D6934E50C3DB36E89B127B8A622B120F6721":"60FED4BA255A9D31C961EB74C6356D68C049B8923B61FA6CE669622E60F29FB6":"7903FE1008B8BC99A41AE9E95628BC64F2F1B20C2D7E9F5177A3C294D4462299":MBEDTLS_MD_SHA256:"test":"3045022100f1abb023518351cd71d881567b1ea663ed3efcf6c5132b354f28d3b0b7d383670220019f4113742a2b14bd25926b49c649155f267e60d3814b4c0cc84250e46f0083":10000:0:0
+
+ECDSA restartable sign/verify: ECKEY, max_ops=10000
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_SHA256_C
+pk_sign_verify_restart:MBEDTLS_PK_ECKEY:MBEDTLS_ECP_DP_SECP256R1:"C9AFA9D845BA75166B5C215767B1D6934E50C3DB36E89B127B8A622B120F6721":"60FED4BA255A9D31C961EB74C6356D68C049B8923B61FA6CE669622E60F29FB6":"7903FE1008B8BC99A41AE9E95628BC64F2F1B20C2D7E9F5177A3C294D4462299":MBEDTLS_MD_SHA256:"test":"3045022100f1abb023518351cd71d881567b1ea663ed3efcf6c5132b354f28d3b0b7d383670220019f4113742a2b14bd25926b49c649155f267e60d3814b4c0cc84250e46f0083":10000:0:0
+
+ECDSA restartable sign/verify: ECDSA, max_ops=250
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_SHA256_C
+pk_sign_verify_restart:MBEDTLS_PK_ECDSA:MBEDTLS_ECP_DP_SECP256R1:"C9AFA9D845BA75166B5C215767B1D6934E50C3DB36E89B127B8A622B120F6721":"60FED4BA255A9D31C961EB74C6356D68C049B8923B61FA6CE669622E60F29FB6":"7903FE1008B8BC99A41AE9E95628BC64F2F1B20C2D7E9F5177A3C294D4462299":MBEDTLS_MD_SHA256:"test":"3045022100f1abb023518351cd71d881567b1ea663ed3efcf6c5132b354f28d3b0b7d383670220019f4113742a2b14bd25926b49c649155f267e60d3814b4c0cc84250e46f0083":250:2:64
+
+ECDSA restartable sign/verify: ECKEY, max_ops=250
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_SHA256_C
+pk_sign_verify_restart:MBEDTLS_PK_ECKEY:MBEDTLS_ECP_DP_SECP256R1:"C9AFA9D845BA75166B5C215767B1D6934E50C3DB36E89B127B8A622B120F6721":"60FED4BA255A9D31C961EB74C6356D68C049B8923B61FA6CE669622E60F29FB6":"7903FE1008B8BC99A41AE9E95628BC64F2F1B20C2D7E9F5177A3C294D4462299":MBEDTLS_MD_SHA256:"test":"3045022100f1abb023518351cd71d881567b1ea663ed3efcf6c5132b354f28d3b0b7d383670220019f4113742a2b14bd25926b49c649155f267e60d3814b4c0cc84250e46f0083":250:2:64
diff --git a/tests/suites/test_suite_pk.function b/tests/suites/test_suite_pk.function
index c0c987d..a215836 100644
--- a/tests/suites/test_suite_pk.function
+++ b/tests/suites/test_suite_pk.function
@@ -131,6 +131,14 @@
     mbedtls_rsa_context *rsa;
     mbedtls_pk_context pk;
     int msg_len;
+    mbedtls_pk_restart_ctx *rs_ctx = NULL;
+#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
+    mbedtls_pk_restart_ctx ctx;
+
+    rs_ctx = &ctx;
+    mbedtls_pk_restart_init( rs_ctx );
+    mbedtls_ecp_set_max_ops( 42 );
+#endif
 
     mbedtls_pk_init( &pk );
 
@@ -154,7 +162,13 @@
     TEST_ASSERT( mbedtls_pk_verify( &pk, digest, hash_result, 0,
                             result_str, mbedtls_pk_get_len( &pk ) ) == result );
 
+    TEST_ASSERT( mbedtls_pk_verify_restartable( &pk, digest, hash_result, 0,
+                    result_str, mbedtls_pk_get_len( &pk ), rs_ctx ) == result );
+
 exit:
+#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
+    mbedtls_pk_restart_free( rs_ctx );
+#endif
     mbedtls_pk_free( &pk );
 }
 /* END_CASE */
@@ -257,12 +271,122 @@
 }
 /* END_CASE */
 
+/* BEGIN_CASE depends_on:MBEDTLS_ECP_RESTARTABLE:MBEDTLS_ECDSA_C:MBEDTLS_ECDSA_DETERMINISTIC */
+void pk_sign_verify_restart( int pk_type, int grp_id, char *d_str,
+                              char *QX_str, char *QY_str,
+                              int md_alg, char *msg, char *sig_str,
+                              int max_ops, int min_restart, int max_restart )
+{
+    int ret, cnt_restart;
+    mbedtls_pk_restart_ctx rs_ctx;
+    mbedtls_pk_context prv, pub;
+    unsigned char hash[MBEDTLS_MD_MAX_SIZE];
+    unsigned char sig[MBEDTLS_ECDSA_MAX_LEN];
+    unsigned char sig_check[MBEDTLS_ECDSA_MAX_LEN];
+    size_t hlen, slen, slen_check;
+    const mbedtls_md_info_t *md_info;
+
+    mbedtls_pk_restart_init( &rs_ctx );
+    mbedtls_pk_init( &prv );
+    mbedtls_pk_init( &pub );
+    memset( hash, 0, sizeof( hash ) );
+    memset( sig, 0, sizeof( sig ) );
+    memset( sig_check, 0, sizeof( sig_check ) );
+
+    TEST_ASSERT( mbedtls_pk_setup( &prv, mbedtls_pk_info_from_type( pk_type ) ) == 0 );
+    TEST_ASSERT( mbedtls_ecp_group_load( &mbedtls_pk_ec( prv )->grp, grp_id ) == 0 );
+    TEST_ASSERT( mbedtls_mpi_read_string( &mbedtls_pk_ec( prv )->d, 16, d_str ) == 0 );
+
+    TEST_ASSERT( mbedtls_pk_setup( &pub, mbedtls_pk_info_from_type( pk_type ) ) == 0 );
+    TEST_ASSERT( mbedtls_ecp_group_load( &mbedtls_pk_ec( pub )->grp, grp_id ) == 0 );
+    TEST_ASSERT( mbedtls_ecp_point_read_string( &mbedtls_pk_ec( pub )->Q, 16, QX_str, QY_str ) == 0 );
+
+    slen_check = unhexify( sig_check, sig_str );
+
+    md_info = mbedtls_md_info_from_type( md_alg );
+    TEST_ASSERT( md_info != NULL );
+
+    hlen = mbedtls_md_get_size( md_info );
+    mbedtls_md( md_info, (const unsigned char *) msg, strlen( msg ), hash );
+
+    mbedtls_ecp_set_max_ops( max_ops );
+
+    slen = sizeof( sig );
+    cnt_restart = 0;
+    do {
+        ret = mbedtls_pk_sign_restartable( &prv, md_alg, hash, hlen,
+                                            sig, &slen, NULL, NULL, &rs_ctx );
+    } while( ret == MBEDTLS_ERR_ECP_IN_PROGRESS && ++cnt_restart );
+
+    TEST_ASSERT( ret == 0 );
+    TEST_ASSERT( slen == slen_check );
+    TEST_ASSERT( memcmp( sig, sig_check, slen ) == 0 );
+
+    TEST_ASSERT( cnt_restart >= min_restart );
+    TEST_ASSERT( cnt_restart <= max_restart );
+
+    cnt_restart = 0;
+    do {
+        ret = mbedtls_pk_verify_restartable( &pub, md_alg,
+                                 hash, hlen, sig, slen, &rs_ctx );
+    } while( ret == MBEDTLS_ERR_ECP_IN_PROGRESS && ++cnt_restart );
+
+    TEST_ASSERT( ret == 0 );
+    TEST_ASSERT( cnt_restart >= min_restart );
+    TEST_ASSERT( cnt_restart <= max_restart );
+
+    hash[0]++;
+    do {
+        ret = mbedtls_pk_verify_restartable( &pub, md_alg,
+                                 hash, hlen, sig, slen, &rs_ctx );
+    } while( ret == MBEDTLS_ERR_ECP_IN_PROGRESS );
+    TEST_ASSERT( ret != 0 );
+    hash[0]--;
+
+    sig[0]++;
+    do {
+        ret = mbedtls_pk_verify_restartable( &pub, md_alg,
+                                 hash, hlen, sig, slen, &rs_ctx );
+    } while( ret == MBEDTLS_ERR_ECP_IN_PROGRESS );
+    TEST_ASSERT( ret != 0 );
+    sig[0]--;
+
+    /* Do we leak memory when aborting? try verify then sign
+     * This test only makes sense when we actually restart */
+    if( min_restart > 0 )
+    {
+        ret = mbedtls_pk_verify_restartable( &pub, md_alg,
+                                 hash, hlen, sig, slen, &rs_ctx );
+        TEST_ASSERT( ret == MBEDTLS_ERR_ECP_IN_PROGRESS );
+        mbedtls_pk_restart_free( &rs_ctx );
+
+        slen = sizeof( sig );
+        ret = mbedtls_pk_sign_restartable( &prv, md_alg, hash, hlen,
+                                            sig, &slen, NULL, NULL, &rs_ctx );
+        TEST_ASSERT( ret == MBEDTLS_ERR_ECP_IN_PROGRESS );
+    }
+
+exit:
+    mbedtls_pk_restart_free( &rs_ctx );
+    mbedtls_pk_free( &prv );
+    mbedtls_pk_free( &pub );
+}
+/* END_CASE */
+
 /* BEGIN_CASE depends_on:MBEDTLS_SHA256_C */
 void pk_sign_verify( int type, int sign_ret, int verify_ret )
 {
     mbedtls_pk_context pk;
     unsigned char hash[50], sig[5000];
     size_t sig_len;
+    void *rs_ctx = NULL;
+#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
+    mbedtls_pk_restart_ctx ctx;
+
+    rs_ctx = &ctx;
+    mbedtls_pk_restart_init( rs_ctx );
+    mbedtls_ecp_set_max_ops( 42000 );
+#endif
 
     mbedtls_pk_init( &pk );
 
@@ -272,13 +396,49 @@
     TEST_ASSERT( mbedtls_pk_setup( &pk, mbedtls_pk_info_from_type( type ) ) == 0 );
     TEST_ASSERT( pk_genkey( &pk ) == 0 );
 
-    TEST_ASSERT( mbedtls_pk_sign( &pk, MBEDTLS_MD_SHA256, hash, sizeof hash,
-                          sig, &sig_len, rnd_std_rand, NULL ) == sign_ret );
+    TEST_ASSERT( mbedtls_pk_sign_restartable( &pk, MBEDTLS_MD_SHA256,
+                 hash, sizeof hash, sig, &sig_len,
+                 rnd_std_rand, NULL, rs_ctx ) == sign_ret );
 
     TEST_ASSERT( mbedtls_pk_verify( &pk, MBEDTLS_MD_SHA256,
                             hash, sizeof hash, sig, sig_len ) == verify_ret );
 
+    if( verify_ret == 0 )
+    {
+        hash[0]++;
+        TEST_ASSERT( mbedtls_pk_verify( &pk, MBEDTLS_MD_SHA256,
+                                hash, sizeof hash, sig, sig_len ) != 0 );
+        hash[0]--;
+
+        sig[0]++;
+        TEST_ASSERT( mbedtls_pk_verify( &pk, MBEDTLS_MD_SHA256,
+                                hash, sizeof hash, sig, sig_len ) != 0 );
+        sig[0]--;
+    }
+
+    TEST_ASSERT( mbedtls_pk_sign( &pk, MBEDTLS_MD_SHA256, hash, sizeof hash,
+                          sig, &sig_len, rnd_std_rand, NULL ) == sign_ret );
+
+    TEST_ASSERT( mbedtls_pk_verify_restartable( &pk, MBEDTLS_MD_SHA256,
+                 hash, sizeof hash, sig, sig_len, rs_ctx ) == verify_ret );
+
+    if( verify_ret == 0 )
+    {
+        hash[0]++;
+        TEST_ASSERT( mbedtls_pk_verify_restartable( &pk, MBEDTLS_MD_SHA256,
+                     hash, sizeof hash, sig, sig_len, rs_ctx ) != 0 );
+        hash[0]--;
+
+        sig[0]++;
+        TEST_ASSERT( mbedtls_pk_verify_restartable( &pk, MBEDTLS_MD_SHA256,
+                     hash, sizeof hash, sig, sig_len, rs_ctx ) != 0 );
+        sig[0]--;
+    }
+
 exit:
+#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
+    mbedtls_pk_restart_free( rs_ctx );
+#endif
     mbedtls_pk_free( &pk );
 }
 /* END_CASE */
diff --git a/tests/suites/test_suite_x509parse.data b/tests/suites/test_suite_x509parse.data
index 406cf59..80e49d2 100644
--- a/tests/suites/test_suite_x509parse.data
+++ b/tests/suites/test_suite_x509parse.data
@@ -1877,3 +1877,91 @@
 X509 Get time (Generalized Time invalid leap year not multiple of 4, 100 or 400)
 depends_on:MBEDTLS_X509_USE_C
 x509_get_time:MBEDTLS_ASN1_GENERALIZED_TIME:"19910229000000Z":MBEDTLS_ERR_X509_INVALID_DATE:0:0:0:0:0:0
+
+X509 cert verify restart: trusted EE, max_ops=0 (disabled)
+depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_ECDSA_C:MBEDTLS_SHA256_C:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+x509_verify_restart:"data_files/server5-selfsigned.crt":"data_files/server5-selfsigned.crt":0:0:0:0:0
+
+X509 cert verify restart: trusted EE, max_ops=1
+depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_ECDSA_C:MBEDTLS_SHA256_C:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+x509_verify_restart:"data_files/server5-selfsigned.crt":"data_files/server5-selfsigned.crt":0:0:1:0:0
+
+X509 cert verify restart: no intermediate, max_ops=0 (disabled)
+depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_ECDSA_C:MBEDTLS_SHA256_C:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_ECP_DP_SECP384R1_ENABLED
+x509_verify_restart:"data_files/server5.crt":"data_files/test-ca2.crt":0:0:0:0:0
+
+X509 cert verify restart: no intermediate, max_ops=1
+depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_ECDSA_C:MBEDTLS_SHA256_C:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_ECP_DP_SECP384R1_ENABLED
+x509_verify_restart:"data_files/server5.crt":"data_files/test-ca2.crt":0:0:1:100:10000
+
+X509 cert verify restart: no intermediate, max_ops=40000
+depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_ECDSA_C:MBEDTLS_SHA256_C:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_ECP_DP_SECP384R1_ENABLED
+x509_verify_restart:"data_files/server5.crt":"data_files/test-ca2.crt":0:0:40000:0:0
+
+X509 cert verify restart: no intermediate, max_ops=500
+depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_ECDSA_C:MBEDTLS_SHA256_C:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_ECP_DP_SECP384R1_ENABLED
+x509_verify_restart:"data_files/server5.crt":"data_files/test-ca2.crt":0:0:500:20:80
+
+X509 cert verify restart: no intermediate, badsign, max_ops=0 (disabled)
+depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_ECDSA_C:MBEDTLS_SHA256_C:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_ECP_DP_SECP384R1_ENABLED
+x509_verify_restart:"data_files/server5-badsign.crt":"data_files/test-ca2.crt":MBEDTLS_ERR_X509_CERT_VERIFY_FAILED:MBEDTLS_X509_BADCERT_NOT_TRUSTED:0:0:0
+
+X509 cert verify restart: no intermediate, badsign, max_ops=1
+depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_ECDSA_C:MBEDTLS_SHA256_C:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_ECP_DP_SECP384R1_ENABLED
+x509_verify_restart:"data_files/server5-badsign.crt":"data_files/test-ca2.crt":MBEDTLS_ERR_X509_CERT_VERIFY_FAILED:MBEDTLS_X509_BADCERT_NOT_TRUSTED:1:100:10000
+
+X509 cert verify restart: no intermediate, badsign, max_ops=40000
+depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_ECDSA_C:MBEDTLS_SHA256_C:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_ECP_DP_SECP384R1_ENABLED
+x509_verify_restart:"data_files/server5-badsign.crt":"data_files/test-ca2.crt":MBEDTLS_ERR_X509_CERT_VERIFY_FAILED:MBEDTLS_X509_BADCERT_NOT_TRUSTED:40000:0:0
+
+X509 cert verify restart: no intermediate, badsign, max_ops=500
+depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_ECDSA_C:MBEDTLS_SHA256_C:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_ECP_DP_SECP384R1_ENABLED
+x509_verify_restart:"data_files/server5-badsign.crt":"data_files/test-ca2.crt":MBEDTLS_ERR_X509_CERT_VERIFY_FAILED:MBEDTLS_X509_BADCERT_NOT_TRUSTED:500:20:80
+
+X509 cert verify restart: one int, max_ops=0 (disabled)
+depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_ECDSA_C:MBEDTLS_SHA256_C:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_ECP_DP_SECP384R1_ENABLED:MBEDTLS_RSA_C
+x509_verify_restart:"data_files/server10_int3_int-ca2.crt":"data_files/test-int-ca2.crt":0:0:0:0:0
+
+X509 cert verify restart: one int, max_ops=1
+depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_ECDSA_C:MBEDTLS_SHA256_C:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_ECP_DP_SECP384R1_ENABLED:MBEDTLS_RSA_C
+x509_verify_restart:"data_files/server10_int3_int-ca2.crt":"data_files/test-int-ca2.crt":0:0:1:100:10000
+
+X509 cert verify restart: one int, max_ops=30000
+depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_ECDSA_C:MBEDTLS_SHA256_C:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_ECP_DP_SECP384R1_ENABLED:MBEDTLS_RSA_C
+x509_verify_restart:"data_files/server10_int3_int-ca2.crt":"data_files/test-int-ca2.crt":0:0:30000:0:0
+
+X509 cert verify restart: one int, max_ops=500
+depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_ECDSA_C:MBEDTLS_SHA256_C:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_ECP_DP_SECP384R1_ENABLED:MBEDTLS_RSA_C
+x509_verify_restart:"data_files/server10_int3_int-ca2.crt":"data_files/test-int-ca2.crt":0:0:500:25:100
+
+X509 cert verify restart: one int, EE badsign, max_ops=0 (disabled)
+depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_ECDSA_C:MBEDTLS_SHA256_C:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_ECP_DP_SECP384R1_ENABLED:MBEDTLS_RSA_C
+x509_verify_restart:"data_files/server10-bs_int3.pem":"data_files/test-int-ca2.crt":MBEDTLS_ERR_X509_CERT_VERIFY_FAILED:MBEDTLS_X509_BADCERT_NOT_TRUSTED:0:0:0
+
+X509 cert verify restart: one int, EE badsign, max_ops=1
+depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_ECDSA_C:MBEDTLS_SHA256_C:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_ECP_DP_SECP384R1_ENABLED:MBEDTLS_RSA_C
+x509_verify_restart:"data_files/server10-bs_int3.pem":"data_files/test-int-ca2.crt":MBEDTLS_ERR_X509_CERT_VERIFY_FAILED:MBEDTLS_X509_BADCERT_NOT_TRUSTED:1:100:10000
+
+X509 cert verify restart: one int, EE badsign, max_ops=30000
+depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_ECDSA_C:MBEDTLS_SHA256_C:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_ECP_DP_SECP384R1_ENABLED:MBEDTLS_RSA_C
+x509_verify_restart:"data_files/server10-bs_int3.pem":"data_files/test-int-ca2.crt":MBEDTLS_ERR_X509_CERT_VERIFY_FAILED:MBEDTLS_X509_BADCERT_NOT_TRUSTED:30000:0:0
+
+X509 cert verify restart: one int, EE badsign, max_ops=500
+depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_ECDSA_C:MBEDTLS_SHA256_C:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_ECP_DP_SECP384R1_ENABLED:MBEDTLS_RSA_C
+x509_verify_restart:"data_files/server10-bs_int3.pem":"data_files/test-int-ca2.crt":MBEDTLS_ERR_X509_CERT_VERIFY_FAILED:MBEDTLS_X509_BADCERT_NOT_TRUSTED:500:25:100
+
+X509 cert verify restart: one int, int badsign, max_ops=0 (disabled)
+depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_ECDSA_C:MBEDTLS_SHA256_C:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_ECP_DP_SECP384R1_ENABLED:MBEDTLS_RSA_C
+x509_verify_restart:"data_files/server10_int3-bs.pem":"data_files/test-int-ca2.crt":MBEDTLS_ERR_X509_CERT_VERIFY_FAILED:MBEDTLS_X509_BADCERT_NOT_TRUSTED:0:0:0
+
+X509 cert verify restart: one int, int badsign, max_ops=1
+depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_ECDSA_C:MBEDTLS_SHA256_C:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_ECP_DP_SECP384R1_ENABLED:MBEDTLS_RSA_C
+x509_verify_restart:"data_files/server10_int3-bs.pem":"data_files/test-int-ca2.crt":MBEDTLS_ERR_X509_CERT_VERIFY_FAILED:MBEDTLS_X509_BADCERT_NOT_TRUSTED:1:100:10000
+
+X509 cert verify restart: one int, int badsign, max_ops=30000
+depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_ECDSA_C:MBEDTLS_SHA256_C:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_ECP_DP_SECP384R1_ENABLED:MBEDTLS_RSA_C
+x509_verify_restart:"data_files/server10_int3-bs.pem":"data_files/test-int-ca2.crt":MBEDTLS_ERR_X509_CERT_VERIFY_FAILED:MBEDTLS_X509_BADCERT_NOT_TRUSTED:30000:0:0
+
+X509 cert verify restart: one int, int badsign, max_ops=500
+depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_ECDSA_C:MBEDTLS_SHA256_C:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_ECP_DP_SECP384R1_ENABLED:MBEDTLS_RSA_C
+x509_verify_restart:"data_files/server10_int3-bs.pem":"data_files/test-int-ca2.crt":MBEDTLS_ERR_X509_CERT_VERIFY_FAILED:MBEDTLS_X509_BADCERT_NOT_TRUSTED:500:25:100
diff --git a/tests/suites/test_suite_x509parse.function b/tests/suites/test_suite_x509parse.function
index 06f0108..c19bce8 100644
--- a/tests/suites/test_suite_x509parse.function
+++ b/tests/suites/test_suite_x509parse.function
@@ -261,6 +261,62 @@
 }
 /* END_CASE */
 
+/* BEGIN_CASE depends_on:MBEDTLS_FS_IO:MBEDTLS_X509_CRT_PARSE_C:MBEDTLS_X509_CRL_PARSE_C:MBEDTLS_ECP_RESTARTABLE:MBEDTLS_ECDSA_C */
+void x509_verify_restart( char *crt_file, char *ca_file,
+                          int result, int flags_result,
+                          int max_ops, int min_restart, int max_restart )
+{
+    int ret, cnt_restart;
+    mbedtls_x509_crt_restart_ctx rs_ctx;
+    mbedtls_x509_crt crt;
+    mbedtls_x509_crt ca;
+    uint32_t flags = 0;
+
+    /*
+     * See comments on ecp_test_vect_restart() for op count precision.
+     *
+     * For reference, with mbed TLS 2.6 and default settings:
+     * - ecdsa_verify() for P-256:  ~  6700
+     * - ecdsa_verify() for P-384:  ~ 18800
+     * - x509_verify() for server5 -> test-ca2:             ~ 18800
+     * - x509_verify() for server10 -> int-ca3 -> int-ca2:  ~ 25500
+     */
+
+    mbedtls_x509_crt_restart_init( &rs_ctx );
+    mbedtls_x509_crt_init( &crt );
+    mbedtls_x509_crt_init( &ca );
+
+    TEST_ASSERT( mbedtls_x509_crt_parse_file( &crt, crt_file ) == 0 );
+    TEST_ASSERT( mbedtls_x509_crt_parse_file( &ca, ca_file ) == 0 );
+
+    mbedtls_ecp_set_max_ops( max_ops );
+
+    cnt_restart = 0;
+    do {
+        ret = mbedtls_x509_crt_verify_restartable( &crt, &ca, NULL,
+                &mbedtls_x509_crt_profile_default, NULL, &flags,
+                NULL, NULL, &rs_ctx );
+    } while( ret == MBEDTLS_ERR_ECP_IN_PROGRESS && ++cnt_restart );
+
+    TEST_ASSERT( ret == result );
+    TEST_ASSERT( flags == (uint32_t) flags_result );
+
+    TEST_ASSERT( cnt_restart >= min_restart );
+    TEST_ASSERT( cnt_restart <= max_restart );
+
+    /* Do we leak memory when aborting? */
+    ret = mbedtls_x509_crt_verify_restartable( &crt, &ca, NULL,
+            &mbedtls_x509_crt_profile_default, NULL, &flags,
+            NULL, NULL, &rs_ctx );
+    TEST_ASSERT( ret == result || ret == MBEDTLS_ERR_ECP_IN_PROGRESS );
+
+exit:
+    mbedtls_x509_crt_restart_free( &rs_ctx );
+    mbedtls_x509_crt_free( &crt );
+    mbedtls_x509_crt_free( &ca );
+}
+/* END_CASE */
+
 /* BEGIN_CASE depends_on:MBEDTLS_FS_IO:MBEDTLS_X509_CRT_PARSE_C:MBEDTLS_X509_CRL_PARSE_C */
 void x509_verify( char *crt_file, char *ca_file, char *crl_file,
                   char *cn_name_str, int result, int flags_result,