diff --git a/ChangeLog.d/8825.txt b/ChangeLog.d/8825.txt
new file mode 100644
index 0000000..914bd08
--- /dev/null
+++ b/ChangeLog.d/8825.txt
@@ -0,0 +1,6 @@
+Features
+   * mbedtls_psa_get_random() is always available as soon as
+     MBEDTLS_PSA_CRYPTO_CLIENT is enabled at build time and psa_crypto_init() is
+     called at runtime. This together with MBEDTLS_PSA_RANDOM_STATE can be
+     used as random number generator function (f_rng) and context (p_rng) in
+     legacy functions.
diff --git a/ChangeLog.d/use_exp_mod_core.txt b/ChangeLog.d/use_exp_mod_core.txt
new file mode 100644
index 0000000..8f7193a
--- /dev/null
+++ b/ChangeLog.d/use_exp_mod_core.txt
@@ -0,0 +1,6 @@
+Changes
+   * mbedtls_mpi_exp_mod and code that uses it, notably RSA and DHM operations,
+     have changed their speed/memory compromise as part of a proactive security
+     improvement. The new default value of MBEDTLS_MPI_WINDOW_SIZE roughly
+     preserves the current speed, at the expense of increasing memory
+     consumption.
diff --git a/include/mbedtls/bignum.h b/include/mbedtls/bignum.h
index 931e06d..71d7b97 100644
--- a/include/mbedtls/bignum.h
+++ b/include/mbedtls/bignum.h
@@ -51,15 +51,15 @@
 
 #if !defined(MBEDTLS_MPI_WINDOW_SIZE)
 /*
- * Maximum window size used for modular exponentiation. Default: 2
+ * Maximum window size used for modular exponentiation. Default: 3
  * Minimum value: 1. Maximum value: 6.
  *
  * Result is an array of ( 2 ** MBEDTLS_MPI_WINDOW_SIZE ) MPIs used
- * for the sliding window calculation. (So 64 by default)
+ * for the sliding window calculation. (So 8 by default)
  *
  * Reduction in size, reduces speed.
  */
-#define MBEDTLS_MPI_WINDOW_SIZE                           2        /**< Maximum window size used. */
+#define MBEDTLS_MPI_WINDOW_SIZE                           3        /**< Maximum window size used. */
 #endif /* !MBEDTLS_MPI_WINDOW_SIZE */
 
 #if !defined(MBEDTLS_MPI_MAX_SIZE)
diff --git a/include/mbedtls/psa_util.h b/include/mbedtls/psa_util.h
index 984f031..c78cc23 100644
--- a/include/mbedtls/psa_util.h
+++ b/include/mbedtls/psa_util.h
@@ -21,44 +21,24 @@
  * otherwise error codes would be unknown in test_suite_psa_crypto_util.data.*/
 #include <mbedtls/asn1write.h>
 
-#if defined(MBEDTLS_PSA_CRYPTO_C)
-
-/* Expose whatever RNG the PSA subsystem uses to applications using the
- * mbedtls_xxx API. The declarations and definitions here need to be
- * consistent with the implementation in library/psa_crypto_random_impl.h.
- * See that file for implementation documentation. */
-
-
-/* The type of a `f_rng` random generator function that many library functions
- * take.
- *
- * This type name is not part of the Mbed TLS stable API. It may be renamed
- * or moved without warning.
- */
-typedef int mbedtls_f_rng_t(void *p_rng, unsigned char *output, size_t output_size);
-
-#if defined(MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG)
+#if defined(MBEDTLS_PSA_CRYPTO_CLIENT)
 
 /** The random generator function for the PSA subsystem.
  *
  * This function is suitable as the `f_rng` random generator function
- * parameter of many `mbedtls_xxx` functions. Use #MBEDTLS_PSA_RANDOM_STATE
- * to obtain the \p p_rng parameter.
+ * parameter of many `mbedtls_xxx` functions.
  *
  * The implementation of this function depends on the configuration of the
  * library.
  *
- * \note Depending on the configuration, this may be a function or
- *       a pointer to a function.
- *
  * \note This function may only be used if the PSA crypto subsystem is active.
  *       This means that you must call psa_crypto_init() before any call to
  *       this function, and you must not call this function after calling
  *       mbedtls_psa_crypto_free().
  *
- * \param p_rng         The random generator context. This must be
- *                      #MBEDTLS_PSA_RANDOM_STATE. No other state is
- *                      supported.
+ * \param p_rng         This parameter is only kept for backward compatibility
+ *                      reasons with legacy `f_rng` functions and it's ignored.
+ *                      Set to #MBEDTLS_PSA_RANDOM_STATE or NULL.
  * \param output        The buffer to fill. It must have room for
  *                      \c output_size bytes.
  * \param output_size   The number of bytes to write to \p output.
@@ -80,32 +60,11 @@
 
 /** The random generator state for the PSA subsystem.
  *
- * This macro expands to an expression which is suitable as the `p_rng`
- * random generator state parameter of many `mbedtls_xxx` functions.
- * It must be used in combination with the random generator function
- * mbedtls_psa_get_random().
- *
- * The implementation of this macro depends on the configuration of the
- * library. Do not make any assumption on its nature.
+ * This macro always expands to NULL because the `p_rng` parameter is unused
+ * in mbedtls_psa_get_random(), but it's kept for interface's backward
+ * compatibility.
  */
-#define MBEDTLS_PSA_RANDOM_STATE NULL
-
-#else /* !defined(MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG) */
-
-#if defined(MBEDTLS_CTR_DRBG_C)
-#include "mbedtls/ctr_drbg.h"
-typedef mbedtls_ctr_drbg_context mbedtls_psa_drbg_context_t;
-static mbedtls_f_rng_t *const mbedtls_psa_get_random = mbedtls_ctr_drbg_random;
-#elif defined(MBEDTLS_HMAC_DRBG_C)
-#include "mbedtls/hmac_drbg.h"
-typedef mbedtls_hmac_drbg_context mbedtls_psa_drbg_context_t;
-static mbedtls_f_rng_t *const mbedtls_psa_get_random = mbedtls_hmac_drbg_random;
-#endif
-extern mbedtls_psa_drbg_context_t *const mbedtls_psa_random_state;
-
-#define MBEDTLS_PSA_RANDOM_STATE mbedtls_psa_random_state
-
-#endif /* !defined(MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG) */
+#define MBEDTLS_PSA_RANDOM_STATE    NULL
 
 /** \defgroup psa_tls_helpers TLS helper functions
  * @{
@@ -180,7 +139,7 @@
 {
     return (mbedtls_md_type_t) (psa_alg & PSA_ALG_HASH_MASK);
 }
-#endif /* MBEDTLS_PSA_CRYPTO_C */
+#endif /* MBEDTLS_PSA_CRYPTO_CLIENT */
 
 #if defined(MBEDTLS_PSA_UTIL_HAVE_ECDSA)
 
diff --git a/include/mbedtls/ssl.h b/include/mbedtls/ssl.h
index 78395d2..9a66663 100644
--- a/include/mbedtls/ssl.h
+++ b/include/mbedtls/ssl.h
@@ -1859,7 +1859,8 @@
                                                          *   within a single datagram.  */
 #endif /* MBEDTLS_SSL_PROTO_DTLS */
 
-#if defined(MBEDTLS_SSL_EARLY_DATA) && defined(MBEDTLS_SSL_SRV_C)
+#if defined(MBEDTLS_SSL_EARLY_DATA)
+#if defined(MBEDTLS_SSL_SRV_C)
     /*
      * One of:
      * MBEDTLS_SSL_EARLY_DATA_NO_DISCARD
@@ -1868,6 +1869,8 @@
      */
     uint8_t MBEDTLS_PRIVATE(discard_early_data_record);
 #endif
+    uint32_t MBEDTLS_PRIVATE(total_early_data_size); /*!< Number of received/written early data bytes */
+#endif /* MBEDTLS_SSL_EARLY_DATA */
 
     /*
      * Record layer (outgoing data)
diff --git a/library/bignum.c b/library/bignum.c
index d3d72ab..eecdf1e 100644
--- a/library/bignum.c
+++ b/library/bignum.c
@@ -37,6 +37,19 @@
 
 #include "mbedtls/platform.h"
 
+
+
+/*
+ * Conditionally select an MPI sign in constant time.
+ * (MPI sign is the field s in mbedtls_mpi. It is unsigned short and only 1 and -1 are valid
+ * values.)
+ */
+static inline signed short mbedtls_ct_mpi_sign_if(mbedtls_ct_condition_t cond,
+                                                  signed short sign1, signed short sign2)
+{
+    return (signed short) mbedtls_ct_uint_if(cond, sign1 + 1, sign2 + 1) - 1;
+}
+
 /*
  * Compare signed values in constant time
  */
@@ -112,7 +125,7 @@
     {
         mbedtls_ct_condition_t do_assign = mbedtls_ct_bool(assign);
 
-        X->s = (int) mbedtls_ct_uint_if(do_assign, Y->s, X->s);
+        X->s = mbedtls_ct_mpi_sign_if(do_assign, Y->s, X->s);
 
         mbedtls_mpi_core_cond_assign(X->p, Y->p, Y->n, do_assign);
 
@@ -149,8 +162,8 @@
     MBEDTLS_MPI_CHK(mbedtls_mpi_grow(Y, X->n));
 
     s = X->s;
-    X->s = (int) mbedtls_ct_uint_if(do_swap, Y->s, X->s);
-    Y->s = (int) mbedtls_ct_uint_if(do_swap, s, Y->s);
+    X->s = mbedtls_ct_mpi_sign_if(do_swap, Y->s, X->s);
+    Y->s = mbedtls_ct_mpi_sign_if(do_swap, s, Y->s);
 
     mbedtls_mpi_core_cond_swap(X->p, Y->p, X->n, do_swap);
 
@@ -288,8 +301,7 @@
  * This function is not constant-time. Leading zeros in Y may be removed.
  *
  * Ensure that X does not shrink. This is not guaranteed by the public API,
- * but some code in the bignum module relies on this property, for example
- * in mbedtls_mpi_exp_mod().
+ * but some code in the bignum module might still rely on this property.
  */
 int mbedtls_mpi_copy(mbedtls_mpi *X, const mbedtls_mpi *Y)
 {
@@ -1598,98 +1610,11 @@
     return 0;
 }
 
-static void mpi_montg_init(mbedtls_mpi_uint *mm, const mbedtls_mpi *N)
-{
-    *mm = mbedtls_mpi_core_montmul_init(N->p);
-}
-
-/** Montgomery multiplication: A = A * B * R^-1 mod N  (HAC 14.36)
- *
- * \param[in,out]   A   One of the numbers to multiply.
- *                      It must have at least as many limbs as N
- *                      (A->n >= N->n), and any limbs beyond n are ignored.
- *                      On successful completion, A contains the result of
- *                      the multiplication A * B * R^-1 mod N where
- *                      R = (2^ciL)^n.
- * \param[in]       B   One of the numbers to multiply.
- *                      It must be nonzero and must not have more limbs than N
- *                      (B->n <= N->n).
- * \param[in]       N   The modulus. \p N must be odd.
- * \param           mm  The value calculated by `mpi_montg_init(&mm, N)`.
- *                      This is -N^-1 mod 2^ciL.
- * \param[in,out]   T   A bignum for temporary storage.
- *                      It must be at least twice the limb size of N plus 1
- *                      (T->n >= 2 * N->n + 1).
- *                      Its initial content is unused and
- *                      its final content is indeterminate.
- *                      It does not get reallocated.
- */
-static void mpi_montmul(mbedtls_mpi *A, const mbedtls_mpi *B,
-                        const mbedtls_mpi *N, mbedtls_mpi_uint mm,
-                        mbedtls_mpi *T)
-{
-    mbedtls_mpi_core_montmul(A->p, A->p, B->p, B->n, N->p, N->n, mm, T->p);
-}
-
-/*
- * Montgomery reduction: A = A * R^-1 mod N
- *
- * See mpi_montmul() regarding constraints and guarantees on the parameters.
- */
-static void mpi_montred(mbedtls_mpi *A, const mbedtls_mpi *N,
-                        mbedtls_mpi_uint mm, mbedtls_mpi *T)
-{
-    mbedtls_mpi_uint z = 1;
-    mbedtls_mpi U;
-    U.n = 1;
-    U.s = 1;
-    U.p = &z;
-
-    mpi_montmul(A, &U, N, mm, T);
-}
-
-/**
- * Select an MPI from a table without leaking the index.
- *
- * This is functionally equivalent to mbedtls_mpi_copy(R, T[idx]) except it
- * reads the entire table in order to avoid leaking the value of idx to an
- * attacker able to observe memory access patterns.
- *
- * \param[out] R        Where to write the selected MPI.
- * \param[in] T         The table to read from.
- * \param[in] T_size    The number of elements in the table.
- * \param[in] idx       The index of the element to select;
- *                      this must satisfy 0 <= idx < T_size.
- *
- * \return \c 0 on success, or a negative error code.
- */
-static int mpi_select(mbedtls_mpi *R, const mbedtls_mpi *T, size_t T_size, size_t idx)
-{
-    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
-
-    for (size_t i = 0; i < T_size; i++) {
-        MBEDTLS_MPI_CHK(mbedtls_mpi_safe_cond_assign(R, &T[i],
-                                                     (unsigned char) mbedtls_ct_uint_eq(i, idx)));
-    }
-cleanup:
-    return ret;
-}
-
-/*
- * Sliding-window exponentiation: X = A^E mod N  (HAC 14.85)
- */
 int mbedtls_mpi_exp_mod(mbedtls_mpi *X, const mbedtls_mpi *A,
                         const mbedtls_mpi *E, const mbedtls_mpi *N,
                         mbedtls_mpi *prec_RR)
 {
     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
-    size_t window_bitsize;
-    size_t i, j, nblimbs;
-    size_t bufsize, nbits;
-    size_t exponent_bits_in_window = 0;
-    mbedtls_mpi_uint ei, mm, state;
-    mbedtls_mpi RR, T, W[(size_t) 1 << MBEDTLS_MPI_WINDOW_SIZE], WW, Apos;
-    int neg;
 
     if (mbedtls_mpi_cmp_int(N, 0) <= 0 || (N->p[0] & 1) == 0) {
         return MBEDTLS_ERR_MPI_BAD_INPUT_DATA;
@@ -1705,261 +1630,86 @@
     }
 
     /*
-     * Init temps and window size
+     * Ensure that the exponent that we are passing to the core is not NULL.
      */
-    mpi_montg_init(&mm, N);
-    mbedtls_mpi_init(&RR); mbedtls_mpi_init(&T);
-    mbedtls_mpi_init(&Apos);
-    mbedtls_mpi_init(&WW);
-    memset(W, 0, sizeof(W));
-
-    i = mbedtls_mpi_bitlen(E);
-
-    window_bitsize = (i > 671) ? 6 : (i > 239) ? 5 :
-                     (i >  79) ? 4 : (i >  23) ? 3 : 1;
-
-#if (MBEDTLS_MPI_WINDOW_SIZE < 6)
-    if (window_bitsize > MBEDTLS_MPI_WINDOW_SIZE) {
-        window_bitsize = MBEDTLS_MPI_WINDOW_SIZE;
+    if (E->n == 0) {
+        ret = mbedtls_mpi_lset(X, 1);
+        return ret;
     }
-#endif
-
-    const size_t w_table_used_size = (size_t) 1 << window_bitsize;
 
     /*
-     * This function is not constant-trace: its memory accesses depend on the
-     * exponent value. To defend against timing attacks, callers (such as RSA
-     * and DHM) should use exponent blinding. However this is not enough if the
-     * adversary can find the exponent in a single trace, so this function
-     * takes extra precautions against adversaries who can observe memory
-     * access patterns.
-     *
-     * This function performs a series of multiplications by table elements and
-     * squarings, and we want the prevent the adversary from finding out which
-     * table element was used, and from distinguishing between multiplications
-     * and squarings. Firstly, when multiplying by an element of the window
-     * W[i], we do a constant-trace table lookup to obfuscate i. This leaves
-     * squarings as having a different memory access patterns from other
-     * multiplications. So secondly, we put the accumulator in the table as
-     * well, and also do a constant-trace table lookup to multiply by the
-     * accumulator which is W[x_index].
-     *
-     * This way, all multiplications take the form of a lookup-and-multiply.
-     * The number of lookup-and-multiply operations inside each iteration of
-     * the main loop still depends on the bits of the exponent, but since the
-     * other operations in the loop don't have an easily recognizable memory
-     * trace, an adversary is unlikely to be able to observe the exact
-     * patterns.
-     *
-     * An adversary may still be able to recover the exponent if they can
-     * observe both memory accesses and branches. However, branch prediction
-     * exploitation typically requires many traces of execution over the same
-     * data, which is defeated by randomized blinding.
+     * Allocate working memory for mbedtls_mpi_core_exp_mod()
      */
-    const size_t x_index = 0;
-    mbedtls_mpi_init(&W[x_index]);
-
-    j = N->n + 1;
-    /* All W[i] including the accumulator must have at least N->n limbs for
-     * the mpi_montmul() and mpi_montred() calls later. Here we ensure that
-     * W[1] and the accumulator W[x_index] are large enough. later we'll grow
-     * other W[i] to the same length. They must not be shrunk midway through
-     * this function!
-     */
-    MBEDTLS_MPI_CHK(mbedtls_mpi_grow(&W[x_index], j));
-    MBEDTLS_MPI_CHK(mbedtls_mpi_grow(&W[1],  j));
-    MBEDTLS_MPI_CHK(mbedtls_mpi_grow(&T, j * 2));
-
-    /*
-     * Compensate for negative A (and correct at the end)
-     */
-    neg = (A->s == -1);
-    if (neg) {
-        MBEDTLS_MPI_CHK(mbedtls_mpi_copy(&Apos, A));
-        Apos.s = 1;
-        A = &Apos;
+    size_t T_limbs = mbedtls_mpi_core_exp_mod_working_limbs(N->n, E->n);
+    mbedtls_mpi_uint *T = (mbedtls_mpi_uint *) mbedtls_calloc(T_limbs, sizeof(mbedtls_mpi_uint));
+    if (T == NULL) {
+        return MBEDTLS_ERR_MPI_ALLOC_FAILED;
     }
 
+    mbedtls_mpi RR;
+    mbedtls_mpi_init(&RR);
+
     /*
      * If 1st call, pre-compute R^2 mod N
      */
     if (prec_RR == NULL || prec_RR->p == NULL) {
-        MBEDTLS_MPI_CHK(mbedtls_mpi_lset(&RR, 1));
-        MBEDTLS_MPI_CHK(mbedtls_mpi_shift_l(&RR, N->n * 2 * biL));
-        MBEDTLS_MPI_CHK(mbedtls_mpi_mod_mpi(&RR, &RR, N));
+        MBEDTLS_MPI_CHK(mbedtls_mpi_core_get_mont_r2_unsafe(&RR, N));
 
         if (prec_RR != NULL) {
-            memcpy(prec_RR, &RR, sizeof(mbedtls_mpi));
+            *prec_RR = RR;
         }
     } else {
-        memcpy(&RR, prec_RR, sizeof(mbedtls_mpi));
+        MBEDTLS_MPI_CHK(mbedtls_mpi_grow(prec_RR, N->n));
+        RR = *prec_RR;
     }
 
     /*
-     * W[1] = A * R^2 * R^-1 mod N = A * R mod N
+     * To preserve constness we need to make a copy of A. Using X for this to
+     * save memory.
      */
-    if (mbedtls_mpi_cmp_mpi(A, N) >= 0) {
-        MBEDTLS_MPI_CHK(mbedtls_mpi_mod_mpi(&W[1], A, N));
-        /* This should be a no-op because W[1] is already that large before
-         * mbedtls_mpi_mod_mpi(), but it's necessary to avoid an overflow
-         * in mpi_montmul() below, so let's make sure. */
-        MBEDTLS_MPI_CHK(mbedtls_mpi_grow(&W[1], N->n + 1));
-    } else {
-        MBEDTLS_MPI_CHK(mbedtls_mpi_copy(&W[1], A));
-    }
-
-    /* Note that this is safe because W[1] always has at least N->n limbs
-     * (it grew above and was preserved by mbedtls_mpi_copy()). */
-    mpi_montmul(&W[1], &RR, N, mm, &T);
+    MBEDTLS_MPI_CHK(mbedtls_mpi_copy(X, A));
 
     /*
-     * W[x_index] = R^2 * R^-1 mod N = R mod N
+     * Compensate for negative A (and correct at the end).
      */
-    MBEDTLS_MPI_CHK(mbedtls_mpi_copy(&W[x_index], &RR));
-    mpi_montred(&W[x_index], N, mm, &T);
-
-
-    if (window_bitsize > 1) {
-        /*
-         * W[i] = W[1] ^ i
-         *
-         * The first bit of the sliding window is always 1 and therefore we
-         * only need to store the second half of the table.
-         *
-         * (There are two special elements in the table: W[0] for the
-         * accumulator/result and W[1] for A in Montgomery form. Both of these
-         * are already set at this point.)
-         */
-        j = w_table_used_size / 2;
-
-        MBEDTLS_MPI_CHK(mbedtls_mpi_grow(&W[j], N->n + 1));
-        MBEDTLS_MPI_CHK(mbedtls_mpi_copy(&W[j], &W[1]));
-
-        for (i = 0; i < window_bitsize - 1; i++) {
-            mpi_montmul(&W[j], &W[j], N, mm, &T);
-        }
-
-        /*
-         * W[i] = W[i - 1] * W[1]
-         */
-        for (i = j + 1; i < w_table_used_size; i++) {
-            MBEDTLS_MPI_CHK(mbedtls_mpi_grow(&W[i], N->n + 1));
-            MBEDTLS_MPI_CHK(mbedtls_mpi_copy(&W[i], &W[i - 1]));
-
-            mpi_montmul(&W[i], &W[1], N, mm, &T);
-        }
-    }
-
-    nblimbs = E->n;
-    bufsize = 0;
-    nbits   = 0;
-    state   = 0;
-
-    while (1) {
-        if (bufsize == 0) {
-            if (nblimbs == 0) {
-                break;
-            }
-
-            nblimbs--;
-
-            bufsize = sizeof(mbedtls_mpi_uint) << 3;
-        }
-
-        bufsize--;
-
-        ei = (E->p[nblimbs] >> bufsize) & 1;
-
-        /*
-         * skip leading 0s
-         */
-        if (ei == 0 && state == 0) {
-            continue;
-        }
-
-        if (ei == 0 && state == 1) {
-            /*
-             * out of window, square W[x_index]
-             */
-            MBEDTLS_MPI_CHK(mpi_select(&WW, W, w_table_used_size, x_index));
-            mpi_montmul(&W[x_index], &WW, N, mm, &T);
-            continue;
-        }
-
-        /*
-         * add ei to current window
-         */
-        state = 2;
-
-        nbits++;
-        exponent_bits_in_window |= (ei << (window_bitsize - nbits));
-
-        if (nbits == window_bitsize) {
-            /*
-             * W[x_index] = W[x_index]^window_bitsize R^-1 mod N
-             */
-            for (i = 0; i < window_bitsize; i++) {
-                MBEDTLS_MPI_CHK(mpi_select(&WW, W, w_table_used_size,
-                                           x_index));
-                mpi_montmul(&W[x_index], &WW, N, mm, &T);
-            }
-
-            /*
-             * W[x_index] = W[x_index] * W[exponent_bits_in_window] R^-1 mod N
-             */
-            MBEDTLS_MPI_CHK(mpi_select(&WW, W, w_table_used_size,
-                                       exponent_bits_in_window));
-            mpi_montmul(&W[x_index], &WW, N, mm, &T);
-
-            state--;
-            nbits = 0;
-            exponent_bits_in_window = 0;
-        }
-    }
+    X->s = 1;
 
     /*
-     * process the remaining bits
+     * Make sure that X is in a form that is safe for consumption by
+     * the core functions.
+     *
+     * - The core functions will not touch the limbs of X above N->n. The
+     *   result will be correct if those limbs are 0, which the mod call
+     *   ensures.
+     * - Also, X must have at least as many limbs as N for the calls to the
+     *   core functions.
      */
-    for (i = 0; i < nbits; i++) {
-        MBEDTLS_MPI_CHK(mpi_select(&WW, W, w_table_used_size, x_index));
-        mpi_montmul(&W[x_index], &WW, N, mm, &T);
-
-        exponent_bits_in_window <<= 1;
-
-        if ((exponent_bits_in_window & ((size_t) 1 << window_bitsize)) != 0) {
-            MBEDTLS_MPI_CHK(mpi_select(&WW, W, w_table_used_size, 1));
-            mpi_montmul(&W[x_index], &WW, N, mm, &T);
-        }
+    if (mbedtls_mpi_cmp_mpi(X, N) >= 0) {
+        MBEDTLS_MPI_CHK(mbedtls_mpi_mod_mpi(X, X, N));
     }
+    MBEDTLS_MPI_CHK(mbedtls_mpi_grow(X, N->n));
 
     /*
-     * W[x_index] = A^E * R * R^-1 mod N = A^E mod N
+     * Convert to and from Montgomery around mbedtls_mpi_core_exp_mod().
      */
-    mpi_montred(&W[x_index], N, mm, &T);
-
-    if (neg && E->n != 0 && (E->p[0] & 1) != 0) {
-        W[x_index].s = -1;
-        MBEDTLS_MPI_CHK(mbedtls_mpi_add_mpi(&W[x_index], N, &W[x_index]));
-    }
+    mbedtls_mpi_uint mm = mbedtls_mpi_core_montmul_init(N->p);
+    mbedtls_mpi_core_to_mont_rep(X->p, X->p, N->p, N->n, mm, RR.p, T);
+    mbedtls_mpi_core_exp_mod(X->p, X->p, N->p, N->n, E->p, E->n, RR.p, T);
+    mbedtls_mpi_core_from_mont_rep(X->p, X->p, N->p, N->n, mm, T);
 
     /*
-     * Load the result in the output variable.
+     * Correct for negative A.
      */
-    MBEDTLS_MPI_CHK(mbedtls_mpi_copy(X, &W[x_index]));
+    if (A->s == -1 && (E->p[0] & 1) != 0) {
+        mbedtls_ct_condition_t is_x_non_zero = mbedtls_mpi_core_check_zero_ct(X->p, X->n);
+        X->s = mbedtls_ct_mpi_sign_if(is_x_non_zero, -1, 1);
+
+        MBEDTLS_MPI_CHK(mbedtls_mpi_add_mpi(X, N, X));
+    }
 
 cleanup:
 
-    /* The first bit of the sliding window is always 1 and therefore the first
-     * half of the table was unused. */
-    for (i = w_table_used_size/2; i < w_table_used_size; i++) {
-        mbedtls_mpi_free(&W[i]);
-    }
-
-    mbedtls_mpi_free(&W[x_index]);
-    mbedtls_mpi_free(&W[1]);
-    mbedtls_mpi_free(&T);
-    mbedtls_mpi_free(&Apos);
-    mbedtls_mpi_free(&WW);
+    mbedtls_mpi_zeroize_and_free(T, T_limbs);
 
     if (prec_RR == NULL || prec_RR->p == NULL) {
         mbedtls_mpi_free(&RR);
diff --git a/library/bignum_core.c b/library/bignum_core.c
index dfed60d..1a3e0b9 100644
--- a/library/bignum_core.c
+++ b/library/bignum_core.c
@@ -856,16 +856,17 @@
     return c;
 }
 
-mbedtls_mpi_uint mbedtls_mpi_core_check_zero_ct(const mbedtls_mpi_uint *A,
-                                                size_t limbs)
+mbedtls_ct_condition_t mbedtls_mpi_core_check_zero_ct(const mbedtls_mpi_uint *A,
+                                                      size_t limbs)
 {
+    volatile const mbedtls_mpi_uint *force_read_A = A;
     mbedtls_mpi_uint bits = 0;
 
     for (size_t i = 0; i < limbs; i++) {
-        bits |= A[i];
+        bits |= force_read_A[i];
     }
 
-    return bits;
+    return mbedtls_ct_bool(bits);
 }
 
 void mbedtls_mpi_core_to_mont_rep(mbedtls_mpi_uint *X,
diff --git a/library/bignum_core.h b/library/bignum_core.h
index b56be0a..92c8d47 100644
--- a/library/bignum_core.h
+++ b/library/bignum_core.h
@@ -662,11 +662,11 @@
  * \param[in] A   The MPI to test.
  * \param limbs   Number of limbs in \p A.
  *
- * \return        0 if `A == 0`
- *                non-0 (may be any value) if `A != 0`.
+ * \return        MBEDTLS_CT_FALSE if `A == 0`
+ *                MBEDTLS_CT_TRUE  if `A != 0`.
  */
-mbedtls_mpi_uint mbedtls_mpi_core_check_zero_ct(const mbedtls_mpi_uint *A,
-                                                size_t limbs);
+mbedtls_ct_condition_t mbedtls_mpi_core_check_zero_ct(const mbedtls_mpi_uint *A,
+                                                      size_t limbs);
 
 /**
  * \brief          Returns the number of limbs of working memory required for
diff --git a/library/psa_crypto.c b/library/psa_crypto.c
index 3c2b6a0..ec9d115 100644
--- a/library/psa_crypto.c
+++ b/library/psa_crypto.c
@@ -101,11 +101,6 @@
 
 static psa_global_data_t global_data;
 
-#if !defined(MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG)
-mbedtls_psa_drbg_context_t *const mbedtls_psa_random_state =
-    &global_data.rng.drbg;
-#endif
-
 #define GUARD_MODULE_INITIALIZED        \
     if (global_data.initialized == 0)  \
     return PSA_ERROR_BAD_STATE;
@@ -1106,6 +1101,17 @@
      * fully destroyed. */
     PSA_THREADING_CHK_GOTO_EXIT(mbedtls_mutex_lock(
                                     &mbedtls_threading_key_slot_mutex));
+
+    if (slot->state == PSA_SLOT_PENDING_DELETION) {
+        /* Another thread has destroyed the key between us locking the slot
+         * and us gaining the mutex. Unregister from the slot,
+         * and report that the key does not exist. */
+        status = psa_unregister_read(slot);
+
+        PSA_THREADING_CHK_RET(mbedtls_mutex_unlock(
+                                  &mbedtls_threading_key_slot_mutex));
+        return (status == PSA_SUCCESS) ? PSA_ERROR_INVALID_HANDLE : status;
+    }
 #endif
     /* Set the key slot containing the key description's state to
      * PENDING_DELETION. This stops new operations from registering
@@ -1115,10 +1121,10 @@
      * If the key is persistent, we can now delete the copy of the key
      * from memory. If the key is opaque, we require the driver to
      * deal with the deletion. */
-    status = psa_key_slot_state_transition(slot, PSA_SLOT_FULL,
-                                           PSA_SLOT_PENDING_DELETION);
+    overall_status = psa_key_slot_state_transition(slot, PSA_SLOT_FULL,
+                                                   PSA_SLOT_PENDING_DELETION);
 
-    if (status != PSA_SUCCESS) {
+    if (overall_status != PSA_SUCCESS) {
         goto exit;
     }
 
@@ -6940,7 +6946,7 @@
                                                size_t peer_key_length)
 {
     psa_status_t status;
-    uint8_t shared_secret[PSA_RAW_KEY_AGREEMENT_OUTPUT_MAX_SIZE];
+    uint8_t shared_secret[PSA_RAW_KEY_AGREEMENT_OUTPUT_MAX_SIZE] = { 0 };
     size_t shared_secret_length = 0;
     psa_algorithm_t ka_alg = PSA_ALG_KEY_AGREEMENT_GET_BASE(operation->alg);
 
@@ -7103,7 +7109,7 @@
                                MBEDTLS_ENTROPY_SOURCE_STRONG);
 #endif
 
-    mbedtls_psa_drbg_init(MBEDTLS_PSA_RANDOM_STATE);
+    mbedtls_psa_drbg_init(&rng->drbg);
 #endif /* MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG */
 }
 
@@ -7114,7 +7120,7 @@
 #if defined(MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG)
     memset(rng, 0, sizeof(*rng));
 #else /* MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG */
-    mbedtls_psa_drbg_free(MBEDTLS_PSA_RANDOM_STATE);
+    mbedtls_psa_drbg_free(&rng->drbg);
     rng->entropy_free(&rng->entropy);
 #endif /* MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG */
 }
@@ -7129,7 +7135,7 @@
     return PSA_SUCCESS;
 #else /* MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG */
     const unsigned char drbg_seed[] = "PSA";
-    int ret = mbedtls_psa_drbg_seed(&rng->entropy,
+    int ret = mbedtls_psa_drbg_seed(&rng->drbg, &rng->entropy,
                                     drbg_seed, sizeof(drbg_seed) - 1);
     return mbedtls_to_psa_error(ret);
 #endif /* MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG */
@@ -7159,12 +7165,16 @@
 #else /* MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG */
 
     while (output_size > 0) {
+        int ret = MBEDTLS_ERR_PLATFORM_FEATURE_UNSUPPORTED;
         size_t request_size =
             (output_size > MBEDTLS_PSA_RANDOM_MAX_REQUEST ?
              MBEDTLS_PSA_RANDOM_MAX_REQUEST :
              output_size);
-        int ret = mbedtls_psa_get_random(MBEDTLS_PSA_RANDOM_STATE,
-                                         output, request_size);
+#if defined(MBEDTLS_CTR_DRBG_C)
+        ret = mbedtls_ctr_drbg_random(&global_data.rng.drbg, output, request_size);
+#elif defined(MBEDTLS_HMAC_DRBG_C)
+        ret = mbedtls_hmac_drbg_random(&global_data.rng.drbg, output, request_size);
+#endif /* !MBEDTLS_CTR_DRBG_C && !MBEDTLS_HMAC_DRBG_C */
         if (ret != 0) {
             return mbedtls_to_psa_error(ret);
         }
@@ -7175,39 +7185,6 @@
 #endif /* MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG */
 }
 
-/* Wrapper function allowing the classic API to use the PSA RNG.
- *
- * `mbedtls_psa_get_random(MBEDTLS_PSA_RANDOM_STATE, ...)` calls
- * `psa_generate_random(...)`. The state parameter is ignored since the
- * PSA API doesn't support passing an explicit state.
- *
- * In the non-external case, psa_generate_random() calls an
- * `mbedtls_xxx_drbg_random` function which has exactly the same signature
- * and semantics as mbedtls_psa_get_random(). As an optimization,
- * instead of doing this back-and-forth between the PSA API and the
- * classic API, psa_crypto_random_impl.h defines `mbedtls_psa_get_random`
- * as a constant function pointer to `mbedtls_xxx_drbg_random`.
- */
-#if defined(MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG)
-int mbedtls_psa_get_random(void *p_rng,
-                           unsigned char *output,
-                           size_t output_size)
-{
-    /* This function takes a pointer to the RNG state because that's what
-     * classic mbedtls functions using an RNG expect. The PSA RNG manages
-     * its own state internally and doesn't let the caller access that state.
-     * So we just ignore the state parameter, and in practice we'll pass
-     * NULL. */
-    (void) p_rng;
-    psa_status_t status = psa_generate_random(output, output_size);
-    if (status == PSA_SUCCESS) {
-        return 0;
-    } else {
-        return MBEDTLS_ERR_ENTROPY_SOURCE_FAILED;
-    }
-}
-#endif /* MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG */
-
 #if defined(MBEDTLS_PSA_INJECT_ENTROPY)
 psa_status_t mbedtls_psa_inject_entropy(const uint8_t *seed,
                                         size_t seed_size)
diff --git a/library/psa_crypto_random_impl.h b/library/psa_crypto_random_impl.h
index 64b8949..533fb2e 100644
--- a/library/psa_crypto_random_impl.h
+++ b/library/psa_crypto_random_impl.h
@@ -1,14 +1,6 @@
 /** \file psa_crypto_random_impl.h
  *
  * \brief PSA crypto random generator implementation abstraction.
- *
- * The definitions here need to be consistent with the declarations
- * in include/psa_util_internal.h. This file contains some redundant
- * declarations to increase the chance that a compiler will detect
- * inconsistencies if one file is changed without updating the other,
- * but not all potential inconsistencies can be enforced, so make sure
- * to check the public declarations and contracts in
- * include/psa_util_internal.h if you modify this file.
  */
 /*
  *  Copyright The Mbed TLS Contributors
@@ -22,22 +14,12 @@
 
 #if defined(MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG)
 
-#include <string.h>
-#include <mbedtls/entropy.h> // only for error codes
-#include <psa/crypto.h>
-
 typedef mbedtls_psa_external_random_context_t mbedtls_psa_random_context_t;
 
-/* Trivial wrapper around psa_generate_random(). */
-int mbedtls_psa_get_random(void *p_rng,
-                           unsigned char *output,
-                           size_t output_size);
-
-/* The PSA RNG API doesn't need any externally maintained state. */
-#define MBEDTLS_PSA_RANDOM_STATE NULL
-
 #else /* MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG */
 
+#include "mbedtls/entropy.h"
+
 /* Choose a DRBG based on configuration and availability */
 #if defined(MBEDTLS_PSA_HMAC_DRBG_MD_TYPE)
 
@@ -67,11 +49,37 @@
 #error "No hash algorithm available for HMAC_DBRG."
 #endif
 
-#else
+#else /* !MBEDTLS_PSA_HMAC_DRBG_MD_TYPE && !MBEDTLS_CTR_DRBG_C && !MBEDTLS_HMAC_DRBG_C*/
+
 #error "No DRBG module available for the psa_crypto module."
+
+#endif /* !MBEDTLS_PSA_HMAC_DRBG_MD_TYPE && !MBEDTLS_CTR_DRBG_C && !MBEDTLS_HMAC_DRBG_C*/
+
+#if defined(MBEDTLS_CTR_DRBG_C)
+#include "mbedtls/ctr_drbg.h"
+#elif defined(MBEDTLS_HMAC_DRBG_C)
+#include "mbedtls/hmac_drbg.h"
+#endif /* !MBEDTLS_CTR_DRBG_C && !MBEDTLS_HMAC_DRBG_C */
+
+/* The maximum number of bytes that mbedtls_psa_get_random() is expected to return. */
+#if defined(MBEDTLS_CTR_DRBG_C)
+#define MBEDTLS_PSA_RANDOM_MAX_REQUEST MBEDTLS_CTR_DRBG_MAX_REQUEST
+#elif defined(MBEDTLS_HMAC_DRBG_C)
+#define MBEDTLS_PSA_RANDOM_MAX_REQUEST MBEDTLS_HMAC_DRBG_MAX_REQUEST
 #endif
 
-#include "mbedtls/entropy.h"
+#if defined(MBEDTLS_CTR_DRBG_C)
+typedef mbedtls_ctr_drbg_context            mbedtls_psa_drbg_context_t;
+#elif defined(MBEDTLS_HMAC_DRBG_C)
+typedef mbedtls_hmac_drbg_context           mbedtls_psa_drbg_context_t;
+#endif /* !MBEDTLS_CTR_DRBG_C && !MBEDTLS_HMAC_DRBG_C */
+
+typedef struct {
+    void (* entropy_init)(mbedtls_entropy_context *ctx);
+    void (* entropy_free)(mbedtls_entropy_context *ctx);
+    mbedtls_entropy_context entropy;
+    mbedtls_psa_drbg_context_t drbg;
+} mbedtls_psa_random_context_t;
 
 /** Initialize the PSA DRBG.
  *
@@ -99,63 +107,6 @@
 #endif
 }
 
-/** The type of the PSA random generator context.
- *
- * The random generator context is composed of an entropy context and
- * a DRBG context.
- */
-typedef struct {
-    void (* entropy_init)(mbedtls_entropy_context *ctx);
-    void (* entropy_free)(mbedtls_entropy_context *ctx);
-    mbedtls_entropy_context entropy;
-    mbedtls_psa_drbg_context_t drbg;
-} mbedtls_psa_random_context_t;
-
-/* Defined in include/psa_util_internal.h so that it's visible to
- * application code. The declaration here is redundant, but included
- * as a safety net to make it more likely that a future change that
- * accidentally causes the implementation to diverge from the interface
- * will be noticed. */
-/* Do not include the declaration under MSVC because it doesn't accept it
- * ("error C2370: 'mbedtls_psa_get_random' : redefinition; different storage class").
- * Observed with Visual Studio 2013. A known bug apparently:
- * https://stackoverflow.com/questions/8146541/duplicate-external-static-declarations-not-allowed-in-visual-studio
- */
-#if !defined(_MSC_VER)
-static mbedtls_f_rng_t *const mbedtls_psa_get_random;
-#endif
-
-/** The maximum number of bytes that mbedtls_psa_get_random() is expected to
- * return.
- */
-#if defined(MBEDTLS_CTR_DRBG_C)
-#define MBEDTLS_PSA_RANDOM_MAX_REQUEST MBEDTLS_CTR_DRBG_MAX_REQUEST
-#elif defined(MBEDTLS_HMAC_DRBG_C)
-#define MBEDTLS_PSA_RANDOM_MAX_REQUEST MBEDTLS_HMAC_DRBG_MAX_REQUEST
-#endif
-
-/** A pointer to the PSA DRBG state.
- *
- * This variable is only intended to be used through the macro
- * #MBEDTLS_PSA_RANDOM_STATE.
- */
-/* psa_crypto.c sets this variable to a pointer to the DRBG state in the
- * global PSA crypto state. */
-/* The type `mbedtls_psa_drbg_context_t` is defined in
- * include/psa_util_internal.h so that `mbedtls_psa_random_state` can be
- * declared there and be visible to application code. */
-extern mbedtls_psa_drbg_context_t *const mbedtls_psa_random_state;
-
-/** A pointer to the PSA DRBG state.
- *
- * This macro expands to an expression that is suitable as the \c p_rng
- * parameter to pass to mbedtls_psa_get_random().
- *
- * This macro exists in all configurations where the psa_crypto module is
- * enabled. Its expansion depends on the configuration.
- */
-#define MBEDTLS_PSA_RANDOM_STATE mbedtls_psa_random_state
-
 /** Seed the PSA DRBG.
  *
  * \param entropy       An entropy context to read the seed from.
@@ -167,23 +118,15 @@
  * \return              \c 0 on success.
  * \return              An Mbed TLS error code (\c MBEDTLS_ERR_xxx) on failure.
  */
-static inline int mbedtls_psa_drbg_seed(
-    mbedtls_entropy_context *entropy,
-    const unsigned char *custom, size_t len)
+static inline int mbedtls_psa_drbg_seed(mbedtls_psa_drbg_context_t *drbg_ctx,
+                                        mbedtls_entropy_context *entropy,
+                                        const unsigned char *custom, size_t len)
 {
 #if defined(MBEDTLS_CTR_DRBG_C)
-    return mbedtls_ctr_drbg_seed(MBEDTLS_PSA_RANDOM_STATE,
-                                 mbedtls_entropy_func,
-                                 entropy,
-                                 custom, len);
+    return mbedtls_ctr_drbg_seed(drbg_ctx, mbedtls_entropy_func, entropy, custom, len);
 #elif defined(MBEDTLS_HMAC_DRBG_C)
-    const mbedtls_md_info_t *md_info =
-        mbedtls_md_info_from_type(MBEDTLS_PSA_HMAC_DRBG_MD_TYPE);
-    return mbedtls_hmac_drbg_seed(MBEDTLS_PSA_RANDOM_STATE,
-                                  md_info,
-                                  mbedtls_entropy_func,
-                                  entropy,
-                                  custom, len);
+    const mbedtls_md_info_t *md_info = mbedtls_md_info_from_type(MBEDTLS_PSA_HMAC_DRBG_MD_TYPE);
+    return mbedtls_hmac_drbg_seed(drbg_ctx, md_info, mbedtls_entropy_func, entropy, custom, len);
 #endif
 }
 
diff --git a/library/psa_util.c b/library/psa_util.c
index 125b173..4ccc5b0 100644
--- a/library/psa_util.c
+++ b/library/psa_util.c
@@ -18,7 +18,7 @@
 
 #include "psa_util_internal.h"
 
-#if defined(MBEDTLS_PSA_CRYPTO_C)
+#if defined(MBEDTLS_PSA_CRYPTO_CLIENT)
 
 #include <psa/crypto.h>
 
@@ -46,6 +46,7 @@
 #if defined(MBEDTLS_BLOCK_CIPHER_SOME_PSA)
 #include <mbedtls/cipher.h>
 #endif
+#include <mbedtls/entropy.h>
 
 /* PSA_SUCCESS is kept at the top of each error table since
  * it's the most common status when everything functions properly. */
@@ -338,7 +339,31 @@
 }
 #endif /* PSA_WANT_KEY_TYPE_ECC_PUBLIC_KEY */
 
-#endif /* MBEDTLS_PSA_CRYPTO_C */
+/* Wrapper function allowing the classic API to use the PSA RNG.
+ *
+ * `mbedtls_psa_get_random(MBEDTLS_PSA_RANDOM_STATE, ...)` calls
+ * `psa_generate_random(...)`. The state parameter is ignored since the
+ * PSA API doesn't support passing an explicit state.
+ */
+int mbedtls_psa_get_random(void *p_rng,
+                           unsigned char *output,
+                           size_t output_size)
+{
+    /* This function takes a pointer to the RNG state because that's what
+     * classic mbedtls functions using an RNG expect. The PSA RNG manages
+     * its own state internally and doesn't let the caller access that state.
+     * So we just ignore the state parameter, and in practice we'll pass
+     * NULL. */
+    (void) p_rng;
+    psa_status_t status = psa_generate_random(output, output_size);
+    if (status == PSA_SUCCESS) {
+        return 0;
+    } else {
+        return MBEDTLS_ERR_ENTROPY_SOURCE_FAILED;
+    }
+}
+
+#endif /* MBEDTLS_PSA_CRYPTO_CLIENT */
 
 #if defined(MBEDTLS_PSA_UTIL_HAVE_ECDSA)
 
diff --git a/library/psa_util_internal.h b/library/psa_util_internal.h
index 3e62d5f..70a08a0 100644
--- a/library/psa_util_internal.h
+++ b/library/psa_util_internal.h
@@ -16,7 +16,7 @@
 
 #include "psa/crypto.h"
 
-#if defined(MBEDTLS_PSA_CRYPTO_C)
+#if defined(MBEDTLS_PSA_CRYPTO_CLIENT)
 
 /*************************************************************************
  * FFDH
@@ -96,5 +96,5 @@
                           sizeof(error_list)/sizeof(error_list[0]),   \
                           fallback_f)
 
-#endif /* MBEDTLS_PSA_CRYPTO_C */
+#endif /* MBEDTLS_PSA_CRYPTO_CLIENT */
 #endif /* MBEDTLS_PSA_UTIL_INTERNAL_H */
diff --git a/library/ssl_client.c b/library/ssl_client.c
index 6d988a8..8892acf 100644
--- a/library/ssl_client.c
+++ b/library/ssl_client.c
@@ -765,11 +765,6 @@
           MBEDTLS_SSL_SESSION_TICKETS &&
           MBEDTLS_HAVE_TIME */
 
-    if (ssl->conf->f_rng == NULL) {
-        MBEDTLS_SSL_DEBUG_MSG(1, ("no RNG provided"));
-        return MBEDTLS_ERR_SSL_NO_RNG;
-    }
-
     /* Bet on the highest configured version if we are not in a TLS 1.2
      * renegotiation or session resumption.
      */
diff --git a/library/ssl_misc.h b/library/ssl_misc.h
index d8844fc..883b988 100644
--- a/library/ssl_misc.h
+++ b/library/ssl_misc.h
@@ -2150,6 +2150,9 @@
                                            unsigned char *buf,
                                            const unsigned char *end,
                                            size_t *out_len);
+
+int mbedtls_ssl_tls13_check_early_data_len(mbedtls_ssl_context *ssl,
+                                           size_t early_data_len);
 #endif /* MBEDTLS_SSL_EARLY_DATA */
 
 #endif /* MBEDTLS_SSL_PROTO_TLS1_3 */
diff --git a/library/ssl_msg.c b/library/ssl_msg.c
index 2a6d434..0c71157 100644
--- a/library/ssl_msg.c
+++ b/library/ssl_msg.c
@@ -4005,7 +4005,11 @@
                  MBEDTLS_SSL_EARLY_DATA_TRY_TO_DEPROTECT_AND_DISCARD)) {
                 MBEDTLS_SSL_DEBUG_MSG(
                     3, ("EarlyData: deprotect and discard app data records."));
-                /* TODO: Add max_early_data_size check here, see issue 6347 */
+
+                ret = mbedtls_ssl_tls13_check_early_data_len(ssl, rec->data_len);
+                if (ret != 0) {
+                    return ret;
+                }
                 ret = MBEDTLS_ERR_SSL_CONTINUE_PROCESSING;
             }
 #endif /* MBEDTLS_SSL_EARLY_DATA && MBEDTLS_SSL_SRV_C */
@@ -4129,9 +4133,15 @@
      */
     if (ssl->discard_early_data_record == MBEDTLS_SSL_EARLY_DATA_DISCARD) {
         if (rec->type == MBEDTLS_SSL_MSG_APPLICATION_DATA) {
+
+            ret = mbedtls_ssl_tls13_check_early_data_len(ssl, rec->data_len);
+            if (ret != 0) {
+                return ret;
+            }
+
             MBEDTLS_SSL_DEBUG_MSG(
                 3, ("EarlyData: Ignore application message before 2nd ClientHello"));
-            /* TODO: Add max_early_data_size check here, see issue 6347 */
+
             return MBEDTLS_ERR_SSL_CONTINUE_PROCESSING;
         } else if (rec->type == MBEDTLS_SSL_MSG_HANDSHAKE) {
             ssl->discard_early_data_record = MBEDTLS_SSL_EARLY_DATA_NO_DISCARD;
diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index b09db1e..1bfd180 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -1101,6 +1101,7 @@
 #if defined(MBEDTLS_SSL_SRV_C)
     ssl->discard_early_data_record = MBEDTLS_SSL_EARLY_DATA_NO_DISCARD;
 #endif
+    ssl->total_early_data_size = 0;
 #endif /* MBEDTLS_SSL_EARLY_DATA */
 
     /* Initialize structures */
@@ -1361,6 +1362,11 @@
     }
 #endif /* MBEDTLS_SSL_PROTO_TLS1_3 */
 
+    if (ssl->conf->f_rng == NULL) {
+        MBEDTLS_SSL_DEBUG_MSG(1, ("no RNG provided"));
+        return MBEDTLS_ERR_SSL_NO_RNG;
+    }
+
     /* Space for further checks */
 
     return 0;
diff --git a/library/ssl_tls12_server.c b/library/ssl_tls12_server.c
index 5bee188..b49a8ae 100644
--- a/library/ssl_tls12_server.c
+++ b/library/ssl_tls12_server.c
@@ -2178,11 +2178,6 @@
     }
 #endif /* MBEDTLS_SSL_DTLS_HELLO_VERIFY */
 
-    if (ssl->conf->f_rng == NULL) {
-        MBEDTLS_SSL_DEBUG_MSG(1, ("no RNG provided"));
-        return MBEDTLS_ERR_SSL_NO_RNG;
-    }
-
     /*
      *     0  .   0   handshake type
      *     1  .   3   handshake length
diff --git a/library/ssl_tls13_generic.c b/library/ssl_tls13_generic.c
index bc73704..d448a05 100644
--- a/library/ssl_tls13_generic.c
+++ b/library/ssl_tls13_generic.c
@@ -1454,6 +1454,54 @@
 
     return 0;
 }
+
+#if defined(MBEDTLS_SSL_SRV_C)
+int mbedtls_ssl_tls13_check_early_data_len(mbedtls_ssl_context *ssl,
+                                           size_t early_data_len)
+{
+    /*
+     * This function should be called only while an handshake is in progress
+     * and thus a session under negotiation. Add a sanity check to detect a
+     * misuse.
+     */
+    if (ssl->session_negotiate == NULL) {
+        return MBEDTLS_ERR_SSL_INTERNAL_ERROR;
+    }
+
+    /* RFC 8446 section 4.6.1
+     *
+     * A server receiving more than max_early_data_size bytes of 0-RTT data
+     * SHOULD terminate the connection with an "unexpected_message" alert.
+     * Note that if it is still possible to send early_data_len bytes of early
+     * data, it means that early_data_len is smaller than max_early_data_size
+     * (type uint32_t) and can fit in an uint32_t. We use this further
+     * down.
+     */
+    if (early_data_len >
+        (ssl->session_negotiate->max_early_data_size -
+         ssl->total_early_data_size)) {
+
+        MBEDTLS_SSL_DEBUG_MSG(
+            2, ("EarlyData: Too much early data received, %u + %" MBEDTLS_PRINTF_SIZET " > %u",
+                ssl->total_early_data_size, early_data_len,
+                ssl->session_negotiate->max_early_data_size));
+
+        MBEDTLS_SSL_PEND_FATAL_ALERT(
+            MBEDTLS_SSL_ALERT_MSG_UNEXPECTED_MESSAGE,
+            MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE);
+        return MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE;
+    }
+
+    /*
+     * early_data_len has been checked to be less than max_early_data_size
+     * that is uint32_t. Its cast to an uint32_t below is thus safe. We need
+     * the cast to appease some compilers.
+     */
+    ssl->total_early_data_size += (uint32_t) early_data_len;
+
+    return 0;
+}
+#endif /* MBEDTLS_SSL_SRV_C */
 #endif /* MBEDTLS_SSL_EARLY_DATA */
 
 /* Reset SSL context and update hash for handling HRR.
diff --git a/library/ssl_tls13_server.c b/library/ssl_tls13_server.c
index 3a968aa..887c5c6 100644
--- a/library/ssl_tls13_server.c
+++ b/library/ssl_tls13_server.c
@@ -39,6 +39,63 @@
     return ciphersuite_info;
 }
 
+static void ssl_tls13_select_ciphersuite(
+    mbedtls_ssl_context *ssl,
+    const unsigned char *cipher_suites,
+    const unsigned char *cipher_suites_end,
+    int psk_ciphersuite_id,
+    psa_algorithm_t psk_hash_alg,
+    const mbedtls_ssl_ciphersuite_t **selected_ciphersuite_info)
+{
+    *selected_ciphersuite_info = NULL;
+
+    /*
+     * In a compliant ClientHello the byte-length of the list of ciphersuites
+     * is even and this function relies on this fact. This should have been
+     * checked in the main ClientHello parsing function. Double check here.
+     */
+    if ((cipher_suites_end - cipher_suites) & 1) {
+        return;
+    }
+
+    for (const unsigned char *p = cipher_suites;
+         p < cipher_suites_end; p += 2) {
+        /*
+         * "cipher_suites_end - p is even" is an invariant of the loop. As
+         * cipher_suites_end - p > 0, we have cipher_suites_end - p >= 2 and it
+         * is thus safe to read two bytes.
+         */
+        uint16_t id = MBEDTLS_GET_UINT16_BE(p, 0);
+
+        const mbedtls_ssl_ciphersuite_t *info =
+            ssl_tls13_validate_peer_ciphersuite(ssl, id);
+        if (info == NULL) {
+            continue;
+        }
+
+        /*
+         * If a valid PSK ciphersuite identifier has been passed in, we want
+         * an exact match.
+         */
+        if (psk_ciphersuite_id != 0) {
+            if (id != psk_ciphersuite_id) {
+                continue;
+            }
+        } else if (psk_hash_alg != PSA_ALG_NONE) {
+            if (mbedtls_md_psa_alg_from_type((mbedtls_md_type_t) info->mac) !=
+                psk_hash_alg) {
+                continue;
+            }
+        }
+
+        *selected_ciphersuite_info = info;
+        return;
+    }
+
+    MBEDTLS_SSL_DEBUG_MSG(2, ("No matched ciphersuite, psk_ciphersuite_id=%x, psk_hash_alg=%x",
+                              (unsigned) psk_ciphersuite_id, psk_hash_alg));
+}
+
 #if defined(MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_SOME_PSK_ENABLED)
 /* From RFC 8446:
  *
@@ -90,8 +147,30 @@
     return 0;
 }
 
-#define SSL_TLS1_3_OFFERED_PSK_NOT_MATCH   1
-#define SSL_TLS1_3_OFFERED_PSK_MATCH       0
+/*
+ * Non-error return values of
+ * ssl_tls13_offered_psks_check_identity_match_ticket() and
+ * ssl_tls13_offered_psks_check_identity_match(). They are positive to
+ * not collide with error codes that are negative. Zero
+ * (SSL_TLS1_3_PSK_IDENTITY_MATCH) in case of success as it may be propagated
+ * up by the callers of this function as a generic success condition.
+ *
+ * The return value SSL_TLS1_3_PSK_IDENTITY_MATCH_BUT_PSK_NOT_USABLE means
+ * that the pre-shared-key identity matches that of a ticket or an externally-
+ * provisioned pre-shared-key. We have thus been able to retrieve the
+ * attributes of the pre-shared-key but at least one of them does not meet
+ * some criteria and the pre-shared-key cannot be used. For example, a ticket
+ * is expired or its version is not TLS 1.3. Note eventually that the return
+ * value SSL_TLS1_3_PSK_IDENTITY_MATCH_BUT_PSK_NOT_USABLE does not have
+ * anything to do with binder check. A binder check is done only when a
+ * suitable pre-shared-key has been selected and only for that selected
+ * pre-shared-key: if the binder check fails, we fail the handshake and we do
+ * not try to find another pre-shared-key for which the binder check would
+ * succeed as recommended by the specification.
+ */
+#define SSL_TLS1_3_PSK_IDENTITY_DOES_NOT_MATCH 2
+#define SSL_TLS1_3_PSK_IDENTITY_MATCH_BUT_PSK_NOT_USABLE 1
+#define SSL_TLS1_3_PSK_IDENTITY_MATCH 0
 
 #if defined(MBEDTLS_SSL_SESSION_TICKETS)
 MBEDTLS_CHECK_RETURN_CRITICAL
@@ -109,7 +188,6 @@
 {
     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
     unsigned char *ticket_buffer;
-    unsigned int key_exchanges;
 #if defined(MBEDTLS_HAVE_TIME)
     mbedtls_ms_time_t now;
     mbedtls_ms_time_t server_age;
@@ -123,7 +201,7 @@
 
     /* Ticket parser is not configured, Skip */
     if (ssl->conf->f_ticket_parse == NULL || identity_len == 0) {
-        return 0;
+        return SSL_TLS1_3_PSK_IDENTITY_DOES_NOT_MATCH;
     }
 
     /* We create a copy of the encrypted ticket since the ticket parsing
@@ -133,63 +211,51 @@
      */
     ticket_buffer = mbedtls_calloc(1, identity_len);
     if (ticket_buffer == NULL) {
-        MBEDTLS_SSL_DEBUG_MSG(1, ("buffer too small"));
         return MBEDTLS_ERR_SSL_ALLOC_FAILED;
     }
     memcpy(ticket_buffer, identity, identity_len);
 
-    if ((ret = ssl->conf->f_ticket_parse(ssl->conf->p_ticket,
-                                         session,
-                                         ticket_buffer, identity_len)) != 0) {
-        if (ret == MBEDTLS_ERR_SSL_INVALID_MAC) {
-            MBEDTLS_SSL_DEBUG_MSG(3, ("ticket is not authentic"));
-        } else if (ret == MBEDTLS_ERR_SSL_SESSION_TICKET_EXPIRED) {
+    ret = ssl->conf->f_ticket_parse(ssl->conf->p_ticket,
+                                    session,
+                                    ticket_buffer, identity_len);
+    switch (ret) {
+        case 0:
+            ret = SSL_TLS1_3_PSK_IDENTITY_MATCH;
+            break;
+
+        case MBEDTLS_ERR_SSL_SESSION_TICKET_EXPIRED:
             MBEDTLS_SSL_DEBUG_MSG(3, ("ticket is expired"));
-        } else {
+            ret = SSL_TLS1_3_PSK_IDENTITY_MATCH_BUT_PSK_NOT_USABLE;
+            break;
+
+        case MBEDTLS_ERR_SSL_INVALID_MAC:
+            MBEDTLS_SSL_DEBUG_MSG(3, ("ticket is not authentic"));
+            ret = SSL_TLS1_3_PSK_IDENTITY_DOES_NOT_MATCH;
+            break;
+
+        default:
             MBEDTLS_SSL_DEBUG_RET(1, "ticket_parse", ret);
-        }
+            ret = SSL_TLS1_3_PSK_IDENTITY_DOES_NOT_MATCH;
     }
 
     /* We delete the temporary buffer */
     mbedtls_free(ticket_buffer);
 
-    if (ret == 0 && session->tls_version != MBEDTLS_SSL_VERSION_TLS1_3) {
-        MBEDTLS_SSL_DEBUG_MSG(3, ("Ticket TLS version is not 1.3."));
-        /* TODO: Define new return value for this case. */
-        ret = MBEDTLS_ERR_SSL_BAD_PROTOCOL_VERSION;
-    }
-
-    if (ret != 0) {
+    if (ret != SSL_TLS1_3_PSK_IDENTITY_MATCH) {
         goto exit;
     }
 
-    /* RFC 8446 section 4.2.9
-     *
-     * Servers SHOULD NOT send NewSessionTicket with tickets that are not
-     * compatible with the advertised modes; however, if a server does so,
-     * the impact will just be that the client's attempts at resumption fail.
-     *
-     * We regard the ticket with incompatible key exchange modes as not match.
+    /*
+     * The identity matches that of a ticket. Now check that it has suitable
+     * attributes and bet it will not be the case.
      */
-    ret = MBEDTLS_ERR_ERROR_GENERIC_ERROR;
-    MBEDTLS_SSL_PRINT_TICKET_FLAGS(4, session->ticket_flags);
+    ret = SSL_TLS1_3_PSK_IDENTITY_MATCH_BUT_PSK_NOT_USABLE;
 
-    key_exchanges = 0;
-    if (mbedtls_ssl_tls13_session_ticket_allow_psk_ephemeral(session) &&
-        ssl_tls13_key_exchange_is_psk_ephemeral_available(ssl)) {
-        key_exchanges |= MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL;
-    }
-    if (mbedtls_ssl_tls13_session_ticket_allow_psk(session) &&
-        ssl_tls13_key_exchange_is_psk_available(ssl)) {
-        key_exchanges |= MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK;
-    }
-
-    if (key_exchanges == 0) {
-        MBEDTLS_SSL_DEBUG_MSG(3, ("No suitable key exchange mode"));
+    if (session->tls_version != MBEDTLS_SSL_VERSION_TLS1_3) {
+        MBEDTLS_SSL_DEBUG_MSG(3, ("Ticket TLS version is not 1.3."));
         goto exit;
     }
 
-    ret = MBEDTLS_ERR_SSL_SESSION_TICKET_EXPIRED;
 #if defined(MBEDTLS_HAVE_TIME)
     now = mbedtls_ms_time();
 
@@ -242,13 +308,15 @@
                 age_diff));
         goto exit;
     }
-
-    ret = 0;
-
 #endif /* MBEDTLS_HAVE_TIME */
 
+    /*
+     * All good, we have found a suitable ticket.
+     */
+    ret = SSL_TLS1_3_PSK_IDENTITY_MATCH;
+
 exit:
-    if (ret != 0) {
+    if (ret != SSL_TLS1_3_PSK_IDENTITY_MATCH) {
         mbedtls_ssl_session_free(session);
     }
 
@@ -273,13 +341,11 @@
     *psk_type = MBEDTLS_SSL_TLS1_3_PSK_EXTERNAL;
 
     MBEDTLS_SSL_DEBUG_BUF(4, "identity", identity, identity_len);
-    ssl->handshake->resume = 0;
 
 #if defined(MBEDTLS_SSL_SESSION_TICKETS)
-    if (ssl_tls13_offered_psks_check_identity_match_ticket(
-            ssl, identity, identity_len, obfuscated_ticket_age,
-            session) == SSL_TLS1_3_OFFERED_PSK_MATCH) {
-        ssl->handshake->resume = 1;
+    ret = ssl_tls13_offered_psks_check_identity_match_ticket(
+        ssl, identity, identity_len, obfuscated_ticket_age, session);
+    if (ret == SSL_TLS1_3_PSK_IDENTITY_MATCH) {
         *psk_type = MBEDTLS_SSL_TLS1_3_PSK_RESUMPTION;
         ret = mbedtls_ssl_set_hs_psk(ssl,
                                      session->resumption_key,
@@ -294,7 +360,9 @@
                               session->resumption_key_len);
         MBEDTLS_SSL_DEBUG_MSG(4, ("ticket: obfuscated_ticket_age: %u",
                                   (unsigned) obfuscated_ticket_age));
-        return SSL_TLS1_3_OFFERED_PSK_MATCH;
+        return SSL_TLS1_3_PSK_IDENTITY_MATCH;
+    } else if (ret == SSL_TLS1_3_PSK_IDENTITY_MATCH_BUT_PSK_NOT_USABLE) {
+        return SSL_TLS1_3_PSK_IDENTITY_MATCH_BUT_PSK_NOT_USABLE;
     }
 #endif /* MBEDTLS_SSL_SESSION_TICKETS */
 
@@ -302,9 +370,9 @@
     if (ssl->conf->f_psk != NULL) {
         if (ssl->conf->f_psk(
                 ssl->conf->p_psk, ssl, identity, identity_len) == 0) {
-            return SSL_TLS1_3_OFFERED_PSK_MATCH;
+            return SSL_TLS1_3_PSK_IDENTITY_MATCH;
         }
-        return SSL_TLS1_3_OFFERED_PSK_NOT_MATCH;
+        return SSL_TLS1_3_PSK_IDENTITY_DOES_NOT_MATCH;
     }
 
     MBEDTLS_SSL_DEBUG_BUF(5, "identity", identity, identity_len);
@@ -318,12 +386,20 @@
             MBEDTLS_SSL_DEBUG_RET(1, "mbedtls_ssl_set_hs_psk", ret);
             return ret;
         }
-        return SSL_TLS1_3_OFFERED_PSK_MATCH;
+        return SSL_TLS1_3_PSK_IDENTITY_MATCH;
     }
 
-    return SSL_TLS1_3_OFFERED_PSK_NOT_MATCH;
+    return SSL_TLS1_3_PSK_IDENTITY_DOES_NOT_MATCH;
 }
 
+/*
+ * Non-error return values of ssl_tls13_offered_psks_check_binder_match().
+ * They are positive to not collide with error codes that are negative. Zero
+ * (SSL_TLS1_3_BINDER_MATCH) in case of success as it may be propagated up
+ * by the callers of this function as a generic success condition.
+ */
+#define SSL_TLS1_3_BINDER_DOES_NOT_MATCH 1
+#define SSL_TLS1_3_BINDER_MATCH 0
 MBEDTLS_CHECK_RETURN_CRITICAL
 static int ssl_tls13_offered_psks_check_binder_match(
     mbedtls_ssl_context *ssl,
@@ -368,100 +444,16 @@
     MBEDTLS_SSL_DEBUG_BUF(3, "psk binder ( received ): ", binder, binder_len);
 
     if (mbedtls_ct_memcmp(server_computed_binder, binder, binder_len) == 0) {
-        return SSL_TLS1_3_OFFERED_PSK_MATCH;
+        return SSL_TLS1_3_BINDER_MATCH;
     }
 
     mbedtls_platform_zeroize(server_computed_binder,
                              sizeof(server_computed_binder));
-    return SSL_TLS1_3_OFFERED_PSK_NOT_MATCH;
-}
-
-MBEDTLS_CHECK_RETURN_CRITICAL
-static int ssl_tls13_select_ciphersuite_for_psk(
-    mbedtls_ssl_context *ssl,
-    const unsigned char *cipher_suites,
-    const unsigned char *cipher_suites_end,
-    uint16_t *selected_ciphersuite,
-    const mbedtls_ssl_ciphersuite_t **selected_ciphersuite_info)
-{
-    psa_algorithm_t psk_hash_alg = PSA_ALG_SHA_256;
-
-    *selected_ciphersuite = 0;
-    *selected_ciphersuite_info = NULL;
-
-    /* RFC 8446, page 55.
-     *
-     * For externally established PSKs, the Hash algorithm MUST be set when the
-     * PSK is established or default to SHA-256 if no such algorithm is defined.
-     *
-     */
-
-    /*
-     * Search for a matching ciphersuite
-     */
-    for (const unsigned char *p = cipher_suites;
-         p < cipher_suites_end; p += 2) {
-        uint16_t cipher_suite;
-        const mbedtls_ssl_ciphersuite_t *ciphersuite_info;
-
-        cipher_suite = MBEDTLS_GET_UINT16_BE(p, 0);
-        ciphersuite_info = ssl_tls13_validate_peer_ciphersuite(ssl,
-                                                               cipher_suite);
-        if (ciphersuite_info == NULL) {
-            continue;
-        }
-
-        /* MAC of selected ciphersuite MUST be same with PSK binder if exist.
-         * Otherwise, client should reject.
-         */
-        if (psk_hash_alg ==
-            mbedtls_md_psa_alg_from_type((mbedtls_md_type_t) ciphersuite_info->mac)) {
-            *selected_ciphersuite = cipher_suite;
-            *selected_ciphersuite_info = ciphersuite_info;
-            return 0;
-        }
-    }
-    MBEDTLS_SSL_DEBUG_MSG(2, ("No matched ciphersuite"));
-    return MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE;
+    return SSL_TLS1_3_BINDER_DOES_NOT_MATCH;
 }
 
 #if defined(MBEDTLS_SSL_SESSION_TICKETS)
 MBEDTLS_CHECK_RETURN_CRITICAL
-static int ssl_tls13_select_ciphersuite_for_resumption(
-    mbedtls_ssl_context *ssl,
-    const unsigned char *cipher_suites,
-    const unsigned char *cipher_suites_end,
-    mbedtls_ssl_session *session,
-    uint16_t *selected_ciphersuite,
-    const mbedtls_ssl_ciphersuite_t **selected_ciphersuite_info)
-{
-
-    *selected_ciphersuite = 0;
-    *selected_ciphersuite_info = NULL;
-    for (const unsigned char *p = cipher_suites; p < cipher_suites_end; p += 2) {
-        uint16_t cipher_suite = MBEDTLS_GET_UINT16_BE(p, 0);
-        const mbedtls_ssl_ciphersuite_t *ciphersuite_info;
-
-        if (cipher_suite != session->ciphersuite) {
-            continue;
-        }
-
-        ciphersuite_info = ssl_tls13_validate_peer_ciphersuite(ssl,
-                                                               cipher_suite);
-        if (ciphersuite_info == NULL) {
-            continue;
-        }
-
-        *selected_ciphersuite = cipher_suite;
-        *selected_ciphersuite_info = ciphersuite_info;
-
-        return 0;
-    }
-
-    return MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE;
-}
-
-MBEDTLS_CHECK_RETURN_CRITICAL
 static int ssl_tls13_session_copy_ticket(mbedtls_ssl_session *dst,
                                          const mbedtls_ssl_session *src)
 {
@@ -481,6 +473,13 @@
 }
 #endif /* MBEDTLS_SSL_SESSION_TICKETS */
 
+struct psk_attributes {
+    int type;
+    int key_exchange_mode;
+    const mbedtls_ssl_ciphersuite_t *ciphersuite_info;
+};
+#define PSK_ATTRIBUTES_INIT { 0, 0, NULL }
+
 /* Parser for pre_shared_key extension in client hello
  *    struct {
  *        opaque identity<1..2^16-1>;
@@ -507,7 +506,8 @@
     const unsigned char *pre_shared_key_ext,
     const unsigned char *pre_shared_key_ext_end,
     const unsigned char *ciphersuites,
-    const unsigned char *ciphersuites_end)
+    const unsigned char *ciphersuites_end,
+    struct psk_attributes *psk)
 {
     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
     const unsigned char *identities = pre_shared_key_ext;
@@ -558,9 +558,10 @@
         uint32_t obfuscated_ticket_age;
         const unsigned char *binder;
         size_t binder_len;
-        int psk_type;
-        uint16_t cipher_suite;
-        const mbedtls_ssl_ciphersuite_t *ciphersuite_info;
+        int psk_ciphersuite_id;
+        psa_algorithm_t psk_hash_alg;
+        int allowed_key_exchange_modes;
+
 #if defined(MBEDTLS_SSL_SESSION_TICKETS)
         mbedtls_ssl_session session;
         mbedtls_ssl_session_init(&session);
@@ -586,47 +587,74 @@
 
         ret = ssl_tls13_offered_psks_check_identity_match(
             ssl, identity, identity_len, obfuscated_ticket_age,
-            &psk_type, &session);
-        if (ret != SSL_TLS1_3_OFFERED_PSK_MATCH) {
+            &psk->type, &session);
+        if (ret != SSL_TLS1_3_PSK_IDENTITY_MATCH) {
             continue;
         }
 
         MBEDTLS_SSL_DEBUG_MSG(4, ("found matched identity"));
-        switch (psk_type) {
+
+        switch (psk->type) {
             case MBEDTLS_SSL_TLS1_3_PSK_EXTERNAL:
-                ret = ssl_tls13_select_ciphersuite_for_psk(
-                    ssl, ciphersuites, ciphersuites_end,
-                    &cipher_suite, &ciphersuite_info);
+                psk_ciphersuite_id = 0;
+                psk_hash_alg = PSA_ALG_SHA_256;
+                allowed_key_exchange_modes =
+                    MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_ALL;
                 break;
-            case MBEDTLS_SSL_TLS1_3_PSK_RESUMPTION:
 #if defined(MBEDTLS_SSL_SESSION_TICKETS)
-                ret = ssl_tls13_select_ciphersuite_for_resumption(
-                    ssl, ciphersuites, ciphersuites_end, &session,
-                    &cipher_suite, &ciphersuite_info);
-                if (ret != 0) {
-                    mbedtls_ssl_session_free(&session);
-                }
-#else
-                ret = MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE;
-#endif
+            case MBEDTLS_SSL_TLS1_3_PSK_RESUMPTION:
+                psk_ciphersuite_id = session.ciphersuite;
+                psk_hash_alg = PSA_ALG_NONE;
+                ssl->session_negotiate->ticket_flags = session.ticket_flags;
+                allowed_key_exchange_modes =
+                    session.ticket_flags &
+                    MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_ALL;
                 break;
+#endif
             default:
                 return MBEDTLS_ERR_SSL_INTERNAL_ERROR;
         }
-        if (ret != 0) {
-            /* See below, no cipher_suite available, abort handshake */
+
+        psk->key_exchange_mode = MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_NONE;
+
+        if ((allowed_key_exchange_modes &
+             MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL) &&
+            ssl_tls13_key_exchange_is_psk_ephemeral_available(ssl)) {
+            psk->key_exchange_mode = MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL;
+        } else if ((allowed_key_exchange_modes &
+                    MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK) &&
+                   ssl_tls13_key_exchange_is_psk_available(ssl)) {
+            psk->key_exchange_mode = MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK;
+        }
+
+        if (psk->key_exchange_mode == MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_NONE) {
+            MBEDTLS_SSL_DEBUG_MSG(3, ("No suitable PSK key exchange mode"));
+            continue;
+        }
+
+        ssl_tls13_select_ciphersuite(ssl, ciphersuites, ciphersuites_end,
+                                     psk_ciphersuite_id, psk_hash_alg,
+                                     &psk->ciphersuite_info);
+
+        if (psk->ciphersuite_info == NULL) {
+#if defined(MBEDTLS_SSL_SESSION_TICKETS)
+            mbedtls_ssl_session_free(&session);
+#endif
+            /*
+             * We consider finding a ciphersuite suitable for the PSK as part
+             * of the validation of its binder. Thus if we do not find one, we
+             * abort the handshake with a decrypt_error alert.
+             */
             MBEDTLS_SSL_PEND_FATAL_ALERT(
                 MBEDTLS_SSL_ALERT_MSG_DECRYPT_ERROR,
                 MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE);
-            MBEDTLS_SSL_DEBUG_RET(
-                2, "ssl_tls13_select_ciphersuite", ret);
-            return ret;
+            return MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE;
         }
 
         ret = ssl_tls13_offered_psks_check_binder_match(
-            ssl, binder, binder_len, psk_type,
-            mbedtls_md_psa_alg_from_type((mbedtls_md_type_t) ciphersuite_info->mac));
-        if (ret != SSL_TLS1_3_OFFERED_PSK_MATCH) {
+            ssl, binder, binder_len, psk->type,
+            mbedtls_md_psa_alg_from_type((mbedtls_md_type_t) psk->ciphersuite_info->mac));
+        if (ret != SSL_TLS1_3_BINDER_MATCH) {
             /* For security reasons, the handshake should be aborted when we
              * fail to validate a binder value. See RFC 8446 section 4.2.11.2
              * and appendix E.6. */
@@ -644,13 +672,8 @@
 
         matched_identity = identity_id;
 
-        /* Update handshake parameters */
-        ssl->handshake->ciphersuite_info = ciphersuite_info;
-        ssl->session_negotiate->ciphersuite = cipher_suite;
-        MBEDTLS_SSL_DEBUG_MSG(2, ("overwrite ciphersuite: %04x - %s",
-                                  cipher_suite, ciphersuite_info->name));
 #if defined(MBEDTLS_SSL_SESSION_TICKETS)
-        if (psk_type == MBEDTLS_SSL_TLS1_3_PSK_RESUMPTION) {
+        if (psk->type == MBEDTLS_SSL_TLS1_3_PSK_RESUMPTION) {
             ret = ssl_tls13_session_copy_ticket(ssl->session_negotiate,
                                                 &session);
             mbedtls_ssl_session_free(&session);
@@ -676,7 +699,7 @@
         return ret;
     }
     if (matched_identity == -1) {
-        MBEDTLS_SSL_DEBUG_MSG(3, ("No matched PSK or ticket."));
+        MBEDTLS_SSL_DEBUG_MSG(3, ("No usable PSK or ticket."));
         return MBEDTLS_ERR_SSL_UNKNOWN_IDENTITY;
     }
 
@@ -1003,21 +1026,29 @@
 
 #if defined(MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_SOME_PSK_ENABLED)
 MBEDTLS_CHECK_RETURN_CRITICAL
-static int ssl_tls13_ticket_is_kex_mode_permitted(mbedtls_ssl_context *ssl,
-                                                  unsigned int kex_mode)
+static int ssl_tls13_key_exchange_is_psk_available(mbedtls_ssl_context *ssl)
 {
-#if defined(MBEDTLS_SSL_SESSION_TICKETS)
-    if (ssl->handshake->resume) {
-        if (!mbedtls_ssl_tls13_session_ticket_has_flags(
-                ssl->session_negotiate, kex_mode)) {
-            return 0;
-        }
-    }
+#if defined(MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_ENABLED)
+    return mbedtls_ssl_conf_tls13_is_psk_enabled(ssl) &&
+           mbedtls_ssl_tls13_is_psk_supported(ssl) &&
+           ssl_tls13_client_hello_has_exts_for_psk_key_exchange(ssl);
 #else
     ((void) ssl);
-    ((void) kex_mode);
+    return 0;
 #endif
-    return 1;
+}
+
+MBEDTLS_CHECK_RETURN_CRITICAL
+static int ssl_tls13_key_exchange_is_psk_ephemeral_available(mbedtls_ssl_context *ssl)
+{
+#if defined(MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL_ENABLED)
+    return mbedtls_ssl_conf_tls13_is_psk_ephemeral_enabled(ssl) &&
+           mbedtls_ssl_tls13_is_psk_ephemeral_supported(ssl) &&
+           ssl_tls13_client_hello_has_exts_for_psk_ephemeral_key_exchange(ssl);
+#else
+    ((void) ssl);
+    return 0;
+#endif
 }
 #endif /* MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_SOME_PSK_ENABLED */
 
@@ -1033,83 +1064,6 @@
 #endif
 }
 
-MBEDTLS_CHECK_RETURN_CRITICAL
-static int ssl_tls13_key_exchange_is_psk_available(mbedtls_ssl_context *ssl)
-{
-#if defined(MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_ENABLED)
-    return ssl_tls13_ticket_is_kex_mode_permitted(
-        ssl, MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK) &&
-           mbedtls_ssl_conf_tls13_is_psk_enabled(ssl) &&
-           mbedtls_ssl_tls13_is_psk_supported(ssl) &&
-           ssl_tls13_client_hello_has_exts_for_psk_key_exchange(ssl);
-#else
-    ((void) ssl);
-    return 0;
-#endif
-}
-
-MBEDTLS_CHECK_RETURN_CRITICAL
-static int ssl_tls13_key_exchange_is_psk_ephemeral_available(mbedtls_ssl_context *ssl)
-{
-#if defined(MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL_ENABLED)
-    return ssl_tls13_ticket_is_kex_mode_permitted(
-        ssl, MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL) &&
-           mbedtls_ssl_conf_tls13_is_psk_ephemeral_enabled(ssl) &&
-           mbedtls_ssl_tls13_is_psk_ephemeral_supported(ssl) &&
-           ssl_tls13_client_hello_has_exts_for_psk_ephemeral_key_exchange(ssl);
-#else
-    ((void) ssl);
-    return 0;
-#endif
-}
-
-static int ssl_tls13_determine_key_exchange_mode(mbedtls_ssl_context *ssl)
-{
-    /*
-     * Determine the key exchange algorithm to use.
-     * There are three types of key exchanges supported in TLS 1.3:
-     * - (EC)DH with ECDSA,
-     * - (EC)DH with PSK,
-     * - plain PSK.
-     *
-     * The PSK-based key exchanges may additionally be used with 0-RTT.
-     *
-     * Our built-in order of preference is
-     *  1 ) (EC)DHE-PSK Mode ( psk_ephemeral )
-     *  2 ) Certificate Mode ( ephemeral )
-     *  3 ) Plain PSK Mode ( psk )
-     */
-
-    ssl->handshake->key_exchange_mode =
-        MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_NONE;
-
-    if (ssl_tls13_key_exchange_is_psk_ephemeral_available(ssl)) {
-        ssl->handshake->key_exchange_mode =
-            MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL;
-        MBEDTLS_SSL_DEBUG_MSG(2, ("key exchange mode: psk_ephemeral"));
-    } else
-    if (ssl_tls13_key_exchange_is_ephemeral_available(ssl)) {
-        ssl->handshake->key_exchange_mode =
-            MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL;
-        MBEDTLS_SSL_DEBUG_MSG(2, ("key exchange mode: ephemeral"));
-    } else
-    if (ssl_tls13_key_exchange_is_psk_available(ssl)) {
-        ssl->handshake->key_exchange_mode =
-            MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK;
-        MBEDTLS_SSL_DEBUG_MSG(2, ("key exchange mode: psk"));
-    } else {
-        MBEDTLS_SSL_DEBUG_MSG(
-            1,
-            ("ClientHello message misses mandatory extensions."));
-        MBEDTLS_SSL_PEND_FATAL_ALERT(MBEDTLS_SSL_ALERT_MSG_MISSING_EXTENSION,
-                                     MBEDTLS_ERR_SSL_ILLEGAL_PARAMETER);
-        return MBEDTLS_ERR_SSL_ILLEGAL_PARAMETER;
-    }
-
-    return 0;
-
-}
-
 #if defined(MBEDTLS_X509_CRT_PARSE_C) && \
     defined(MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL_ENABLED)
 
@@ -1301,6 +1255,8 @@
     int no_usable_share_for_key_agreement = 0;
 
 #if defined(MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_SOME_PSK_ENABLED)
+    int got_psk = 0;
+    struct psk_attributes psk = PSK_ATTRIBUTES_INIT;
     const unsigned char *pre_shared_key_ext = NULL;
     const unsigned char *pre_shared_key_ext_end = NULL;
 #endif
@@ -1464,37 +1420,20 @@
      */
     MBEDTLS_SSL_DEBUG_BUF(3, "client hello, list of cipher suites",
                           cipher_suites, cipher_suites_len);
-    for (const unsigned char *cipher_suites_p = cipher_suites;
-         cipher_suites_p < cipher_suites_end; cipher_suites_p += 2) {
-        uint16_t cipher_suite;
-        const mbedtls_ssl_ciphersuite_t *ciphersuite_info;
 
-        /*
-         * "cipher_suites_end - cipher_suites_p is even" is an invariant of the
-         * loop. As cipher_suites_end - cipher_suites_p > 0, we have
-         * cipher_suites_end - cipher_suites_p >= 2 and it is thus safe to read
-         * two bytes.
-         */
-        cipher_suite = MBEDTLS_GET_UINT16_BE(cipher_suites_p, 0);
-        ciphersuite_info = ssl_tls13_validate_peer_ciphersuite(
-            ssl, cipher_suite);
-        if (ciphersuite_info == NULL) {
-            continue;
-        }
-
-        ssl->session_negotiate->ciphersuite = cipher_suite;
-        handshake->ciphersuite_info = ciphersuite_info;
-        MBEDTLS_SSL_DEBUG_MSG(2, ("selected ciphersuite: %04x - %s",
-                                  cipher_suite,
-                                  ciphersuite_info->name));
-        break;
-    }
+    ssl_tls13_select_ciphersuite(ssl, cipher_suites, cipher_suites_end,
+                                 0, PSA_ALG_NONE, &handshake->ciphersuite_info);
 
     if (handshake->ciphersuite_info == NULL) {
         MBEDTLS_SSL_PEND_FATAL_ALERT(MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE,
                                      MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE);
         return MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE;
     }
+    ssl->session_negotiate->ciphersuite = handshake->ciphersuite_info->id;
+
+    MBEDTLS_SSL_DEBUG_MSG(2, ("selected ciphersuite: %04x - %s",
+                              ((unsigned) handshake->ciphersuite_info->id),
+                              handshake->ciphersuite_info->name));
 
     /* ...
      * opaque legacy_compression_methods<1..2^8-1>;
@@ -1734,10 +1673,11 @@
     /* Update checksum with either
      * - The entire content of the CH message, if no PSK extension is present
      * - The content up to but excluding the PSK extension, if present.
+     * Always parse the pre-shared-key extension when present in the
+     * ClientHello even if some pre-requisites for PSK key exchange modes are
+     * not met. That way we always validate the syntax of the extension.
      */
-    /* If we've settled on a PSK-based exchange, parse PSK identity ext */
-    if (ssl_tls13_key_exchange_is_psk_available(ssl) ||
-        ssl_tls13_key_exchange_is_psk_ephemeral_available(ssl)) {
+    if (handshake->received_extensions & MBEDTLS_SSL_EXT_MASK(PRE_SHARED_KEY)) {
         ret = handshake->update_checksum(ssl, buf,
                                          pre_shared_key_ext - buf);
         if (0 != ret) {
@@ -1748,10 +1688,11 @@
                                                  pre_shared_key_ext,
                                                  pre_shared_key_ext_end,
                                                  cipher_suites,
-                                                 cipher_suites_end);
-        if (ret == MBEDTLS_ERR_SSL_UNKNOWN_IDENTITY) {
-            handshake->received_extensions &= ~MBEDTLS_SSL_EXT_MASK(PRE_SHARED_KEY);
-        } else if (ret != 0) {
+                                                 cipher_suites_end,
+                                                 &psk);
+        if (ret == 0) {
+            got_psk = 1;
+        } else if (ret != MBEDTLS_ERR_SSL_UNKNOWN_IDENTITY) {
             MBEDTLS_SSL_DEBUG_RET(
                 1, "ssl_tls13_parse_pre_shared_key_ext", ret);
             return ret;
@@ -1766,12 +1707,68 @@
         }
     }
 
-    ret = ssl_tls13_determine_key_exchange_mode(ssl);
-    if (ret < 0) {
-        return ret;
+    /*
+     * Determine the key exchange algorithm to use.
+     * There are three types of key exchanges supported in TLS 1.3:
+     * - (EC)DH with ECDSA,
+     * - (EC)DH with PSK,
+     * - plain PSK.
+     *
+     * The PSK-based key exchanges may additionally be used with 0-RTT.
+     *
+     * Our built-in order of preference is
+     *  1 ) (EC)DHE-PSK Mode ( psk_ephemeral )
+     *  2 ) Certificate Mode ( ephemeral )
+     *  3 ) Plain PSK Mode ( psk )
+     */
+#if defined(MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_SOME_PSK_ENABLED)
+    if (got_psk && (psk.key_exchange_mode ==
+                    MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL)) {
+        handshake->key_exchange_mode =
+            MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL;
+        MBEDTLS_SSL_DEBUG_MSG(2, ("key exchange mode: psk_ephemeral"));
+
+    } else
+#endif
+    if (ssl_tls13_key_exchange_is_ephemeral_available(ssl)) {
+        handshake->key_exchange_mode =
+            MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL;
+        MBEDTLS_SSL_DEBUG_MSG(2, ("key exchange mode: ephemeral"));
+
+    }
+#if defined(MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_SOME_PSK_ENABLED)
+    else if (got_psk && (psk.key_exchange_mode ==
+                         MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK)) {
+        handshake->key_exchange_mode = MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK;
+        MBEDTLS_SSL_DEBUG_MSG(2, ("key exchange mode: psk"));
+    }
+#endif
+    else {
+        MBEDTLS_SSL_DEBUG_MSG(
+            1,
+            ("ClientHello message misses mandatory extensions."));
+        MBEDTLS_SSL_PEND_FATAL_ALERT(MBEDTLS_SSL_ALERT_MSG_MISSING_EXTENSION,
+                                     MBEDTLS_ERR_SSL_ILLEGAL_PARAMETER);
+        return MBEDTLS_ERR_SSL_ILLEGAL_PARAMETER;
     }
 
-    if (ssl->handshake->key_exchange_mode !=
+#if defined(MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_SOME_PSK_ENABLED)
+    if (handshake->key_exchange_mode &
+        MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_ALL) {
+        handshake->ciphersuite_info = psk.ciphersuite_info;
+        ssl->session_negotiate->ciphersuite = psk.ciphersuite_info->id;
+
+        MBEDTLS_SSL_DEBUG_MSG(2, ("Select PSK ciphersuite: %04x - %s",
+                                  ((unsigned) psk.ciphersuite_info->id),
+                                  psk.ciphersuite_info->name));
+
+        if (psk.type == MBEDTLS_SSL_TLS1_3_PSK_RESUMPTION) {
+            handshake->resume = 1;
+        }
+    }
+#endif
+
+    if (handshake->key_exchange_mode !=
         MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK) {
         hrr_required = (no_usable_share_for_key_agreement != 0);
     }
@@ -1973,10 +1970,6 @@
     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
     unsigned char *server_randbytes =
         ssl->handshake->randbytes + MBEDTLS_CLIENT_HELLO_RANDOM_LEN;
-    if (ssl->conf->f_rng == NULL) {
-        MBEDTLS_SSL_DEBUG_MSG(1, ("no RNG provided"));
-        return MBEDTLS_ERR_SSL_NO_RNG;
-    }
 
     if ((ret = ssl->conf->f_rng(ssl->conf->p_rng, server_randbytes,
                                 MBEDTLS_SERVER_HELLO_RANDOM_LEN)) != 0) {
@@ -2913,17 +2906,14 @@
     }
 
     if (ssl->in_msgtype == MBEDTLS_SSL_MSG_APPLICATION_DATA) {
-        MBEDTLS_SSL_DEBUG_MSG(3, ("Received early data"));
-        /* RFC 8446 section 4.6.1
-         *
-         * A server receiving more than max_early_data_size bytes of 0-RTT data
-         * SHOULD terminate the connection with an "unexpected_message" alert.
-         *
-         * TODO: Add received data size check here.
-         */
         if (ssl->in_offt == NULL) {
+            MBEDTLS_SSL_DEBUG_MSG(3, ("Received early data"));
             /* Set the reading pointer */
             ssl->in_offt = ssl->in_msg;
+            ret = mbedtls_ssl_tls13_check_early_data_len(ssl, ssl->in_msglen);
+            if (ret != 0) {
+                return ret;
+            }
         }
         return SSL_GOT_EARLY_DATA;
     }
@@ -3141,6 +3131,7 @@
         ssl->conf->max_early_data_size > 0) {
         mbedtls_ssl_tls13_session_set_ticket_flags(
             session, MBEDTLS_SSL_TLS1_3_TICKET_ALLOW_EARLY_DATA);
+        session->max_early_data_size = ssl->conf->max_early_data_size;
     }
 #endif /* MBEDTLS_SSL_EARLY_DATA */
 
diff --git a/tests/include/test/ssl_helpers.h b/tests/include/test/ssl_helpers.h
index 5b071f7..335386b 100644
--- a/tests/include/test/ssl_helpers.h
+++ b/tests/include/test/ssl_helpers.h
@@ -114,6 +114,7 @@
     void (*cli_log_fun)(void *, int, const char *, int, const char *);
     int resize_buffers;
     int early_data;
+    int max_early_data_size;
 #if defined(MBEDTLS_SSL_CACHE_C)
     mbedtls_ssl_cache_context *cache;
 #endif
@@ -196,6 +197,13 @@
 #endif /* MBEDTLS_SSL_HANDSHAKE_WITH_CERT_ENABLED */
 
 /*
+ * Random number generator aimed for TLS unitary tests. Its main purpose is to
+ * simplify the set-up of a random number generator for TLS
+ * unitary tests: no need to set up a good entropy source for example.
+ */
+int mbedtls_test_random(void *p_rng, unsigned char *output, size_t output_len);
+
+/*
  * This function can be passed to mbedtls to receive output logs from it. In
  * this case, it will count the instances of a mbedtls_test_ssl_log_pattern
  * in the received logged messages.
diff --git a/tests/opt-testcases/tls13-kex-modes.sh b/tests/opt-testcases/tls13-kex-modes.sh
index 4581bc5..49f06e0 100755
--- a/tests/opt-testcases/tls13-kex-modes.sh
+++ b/tests/opt-testcases/tls13-kex-modes.sh
@@ -23,7 +23,7 @@
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -s "Found PSK KEX MODE" \
             -s "Pre shared key found" \
-            -S "No matched PSK or ticket" \
+            -S "No usable PSK or ticket" \
             -s "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
             -S "key exchange mode: ephemeral"
@@ -41,7 +41,7 @@
             -s "found pre_shared_key extension" \
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -s "Found PSK KEX MODE" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
             -S "key exchange mode: ephemeral"
@@ -78,7 +78,7 @@
             -S "Found PSK_EPHEMERAL KEX MODE" \
             -s "Found PSK KEX MODE" \
             -s "Pre shared key found" \
-            -S "No matched PSK or ticket" \
+            -S "No usable PSK or ticket" \
             -s "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
             -S "key exchange mode: ephemeral"
@@ -96,7 +96,7 @@
             -s "found pre_shared_key extension" \
             -S "Found PSK_EPHEMERAL KEX MODE" \
             -s "Found PSK KEX MODE" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
             -S "key exchange mode: ephemeral"
@@ -133,7 +133,7 @@
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -S "Found PSK KEX MODE" \
             -s "Pre shared key found" \
-            -S "No matched PSK or ticket" \
+            -S "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -s "key exchange mode: psk_ephemeral"  \
             -S "key exchange mode: ephemeral"
@@ -151,7 +151,7 @@
             -s "found pre_shared_key extension" \
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -S "Found PSK KEX MODE" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
             -S "key exchange mode: ephemeral"
@@ -188,7 +188,7 @@
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -s "Found PSK KEX MODE" \
             -s "Pre shared key found" \
-            -S "No matched PSK or ticket" \
+            -S "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -s "key exchange mode: psk_ephemeral"  \
             -S "key exchange mode: ephemeral"
@@ -206,7 +206,7 @@
             -s "found pre_shared_key extension" \
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -s "Found PSK KEX MODE" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
             -S "key exchange mode: ephemeral"
@@ -261,7 +261,7 @@
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -S "Found PSK KEX MODE" \
             -s "Pre shared key found" \
-            -S "No matched PSK or ticket" \
+            -S "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -s "key exchange mode: psk_ephemeral"  \
             -S "key exchange mode: ephemeral"
@@ -280,7 +280,7 @@
             -s "found pre_shared_key extension" \
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -S "Found PSK KEX MODE" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
             -S "key exchange mode: ephemeral"
@@ -319,7 +319,7 @@
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -s "Found PSK KEX MODE" \
             -s "Pre shared key found" \
-            -S "No matched PSK or ticket" \
+            -S "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -s "key exchange mode: psk_ephemeral"  \
             -S "key exchange mode: ephemeral"
@@ -338,7 +338,7 @@
             -s "found pre_shared_key extension" \
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -s "Found PSK KEX MODE" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
             -S "key exchange mode: ephemeral"
@@ -377,7 +377,7 @@
             -S "Found PSK_EPHEMERAL KEX MODE" \
             -s "Found PSK KEX MODE" \
             -s "Pre shared key found" \
-            -S "No matched PSK or ticket" \
+            -S "No usable PSK or ticket" \
             -s "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
             -S "key exchange mode: ephemeral"
@@ -396,7 +396,7 @@
             -s "found pre_shared_key extension" \
             -S "Found PSK_EPHEMERAL KEX MODE" \
             -s "Found PSK KEX MODE" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
             -S "key exchange mode: ephemeral"
@@ -435,7 +435,7 @@
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -S "Found PSK KEX MODE" \
             -s "Pre shared key found" \
-            -S "No matched PSK or ticket" \
+            -S "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -s "key exchange mode: psk_ephemeral"  \
             -S "key exchange mode: ephemeral"
@@ -454,7 +454,7 @@
             -s "found pre_shared_key extension" \
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -S "Found PSK KEX MODE" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
             -s "key exchange mode: ephemeral"
@@ -493,7 +493,7 @@
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -s "Found PSK KEX MODE" \
             -s "Pre shared key found" \
-            -S "No matched PSK or ticket" \
+            -S "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -s "key exchange mode: psk_ephemeral"  \
             -S "key exchange mode: ephemeral"
@@ -512,7 +512,7 @@
             -s "found pre_shared_key extension" \
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -s "Found PSK KEX MODE" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
             -s "key exchange mode: ephemeral"
@@ -550,8 +550,9 @@
             -s "found pre_shared_key extension" \
             -S "Found PSK_EPHEMERAL KEX MODE" \
             -s "Found PSK KEX MODE" \
+            -s "No suitable PSK key exchange mode" \
             -S "Pre shared key found" \
-            -S "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
             -s "key exchange mode: ephemeral"
@@ -572,7 +573,7 @@
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -S "Found PSK KEX MODE" \
             -s "Pre shared key found" \
-            -S "No matched PSK or ticket" \
+            -S "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -s "key exchange mode: psk_ephemeral"  \
             -S "key exchange mode: ephemeral"
@@ -592,7 +593,7 @@
             -s "found pre_shared_key extension" \
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -S "Found PSK KEX MODE" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
             -s "key exchange mode: ephemeral"
@@ -633,7 +634,7 @@
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -s "Found PSK KEX MODE" \
             -s "Pre shared key found" \
-            -S "No matched PSK or ticket" \
+            -S "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -s "key exchange mode: psk_ephemeral"  \
             -S "key exchange mode: ephemeral"
@@ -653,7 +654,7 @@
             -s "found pre_shared_key extension" \
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -s "Found PSK KEX MODE" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
             -s "key exchange mode: ephemeral"
@@ -694,7 +695,7 @@
             -S "Found PSK_EPHEMERAL KEX MODE" \
             -s "Found PSK KEX MODE" \
             -s "Pre shared key found" \
-            -S "No matched PSK or ticket" \
+            -S "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
             -s "key exchange mode: ephemeral"
@@ -733,8 +734,9 @@
             -s "found pre_shared_key extension" \
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -S "Found PSK KEX MODE" \
+            -s "No suitable PSK key exchange mode" \
             -S "Pre shared key found" \
-            -S "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
             -s "key exchange mode: ephemeral"
@@ -754,7 +756,7 @@
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -s "Found PSK KEX MODE" \
             -s "Pre shared key found" \
-            -S "No matched PSK or ticket" \
+            -S "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
             -s "key exchange mode: ephemeral"
@@ -793,7 +795,7 @@
             -S "Found PSK_EPHEMERAL KEX MODE" \
             -s "Found PSK KEX MODE" \
             -s "Pre shared key found" \
-            -S "No matched PSK or ticket" \
+            -S "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
             -s "key exchange mode: ephemeral"
@@ -921,7 +923,7 @@
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -s "Found PSK KEX MODE" \
             -s "Pre shared key found" \
-            -S "No matched PSK or ticket" \
+            -S "No usable PSK or ticket" \
             -s "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
             -S "key exchange mode: ephemeral"
@@ -938,7 +940,7 @@
             -s "found pre_shared_key extension" \
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -s "Found PSK KEX MODE" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
             -S "key exchange mode: ephemeral"
@@ -973,7 +975,7 @@
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -S "Found PSK KEX MODE" \
             -s "Pre shared key found" \
-            -S "No matched PSK or ticket" \
+            -S "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -s "key exchange mode: psk_ephemeral"  \
             -S "key exchange mode: ephemeral"
@@ -990,7 +992,7 @@
             -s "found pre_shared_key extension" \
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -S "Found PSK KEX MODE" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
             -S "key exchange mode: ephemeral"
@@ -1025,7 +1027,7 @@
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -s "Found PSK KEX MODE" \
             -s "Pre shared key found" \
-            -S "No matched PSK or ticket" \
+            -S "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -s "key exchange mode: psk_ephemeral"  \
             -S "key exchange mode: ephemeral"
@@ -1042,7 +1044,7 @@
             -s "found pre_shared_key extension" \
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -s "Found PSK KEX MODE" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
             -S "key exchange mode: ephemeral"
@@ -1078,7 +1080,7 @@
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -S "Found PSK KEX MODE" \
             -s "Pre shared key found" \
-            -S "No matched PSK or ticket" \
+            -S "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -s "key exchange mode: psk_ephemeral"  \
             -S "key exchange mode: ephemeral"
@@ -1096,7 +1098,7 @@
             -s "found pre_shared_key extension" \
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -S "Found PSK KEX MODE" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
             -S "key exchange mode: ephemeral"
@@ -1133,7 +1135,7 @@
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -s "Found PSK KEX MODE" \
             -s "Pre shared key found" \
-            -S "No matched PSK or ticket" \
+            -S "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -s "key exchange mode: psk_ephemeral"  \
             -S "key exchange mode: ephemeral"
@@ -1151,7 +1153,7 @@
             -s "found pre_shared_key extension" \
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -s "Found PSK KEX MODE" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
             -S "key exchange mode: ephemeral"
@@ -1188,7 +1190,7 @@
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -S "Found PSK KEX MODE" \
             -s "Pre shared key found" \
-            -S "No matched PSK or ticket" \
+            -S "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -s "key exchange mode: psk_ephemeral"  \
             -S "key exchange mode: ephemeral"
@@ -1206,7 +1208,7 @@
             -s "found pre_shared_key extension" \
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -S "Found PSK KEX MODE" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
             -s "key exchange mode: ephemeral"
@@ -1243,7 +1245,7 @@
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -s "Found PSK KEX MODE" \
             -s "Pre shared key found" \
-            -S "No matched PSK or ticket" \
+            -S "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -s "key exchange mode: psk_ephemeral"  \
             -S "key exchange mode: ephemeral"
@@ -1261,7 +1263,7 @@
             -s "found pre_shared_key extension" \
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -s "Found PSK KEX MODE" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
             -s "key exchange mode: ephemeral"
@@ -1299,7 +1301,7 @@
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -S "Found PSK KEX MODE" \
             -s "Pre shared key found" \
-            -S "No matched PSK or ticket" \
+            -S "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -s "key exchange mode: psk_ephemeral"  \
             -S "key exchange mode: ephemeral"
@@ -1318,7 +1320,7 @@
             -s "found pre_shared_key extension" \
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -S "Found PSK KEX MODE" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
             -s "key exchange mode: ephemeral"
@@ -1357,7 +1359,7 @@
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -s "Found PSK KEX MODE" \
             -s "Pre shared key found" \
-            -S "No matched PSK or ticket" \
+            -S "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -s "key exchange mode: psk_ephemeral"  \
             -S "key exchange mode: ephemeral"
@@ -1376,7 +1378,7 @@
             -s "found pre_shared_key extension" \
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -s "Found PSK KEX MODE" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
             -s "key exchange mode: ephemeral"
@@ -1413,8 +1415,9 @@
             -s "found pre_shared_key extension" \
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -S "Found PSK KEX MODE" \
+            -s "No suitable PSK key exchange mode" \
             -S "Pre shared key found" \
-            -S "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
             -s "key exchange mode: ephemeral"
@@ -1433,7 +1436,7 @@
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -s "Found PSK KEX MODE" \
             -s "Pre shared key found" \
-            -S "No matched PSK or ticket" \
+            -S "No usable PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
             -s "key exchange mode: ephemeral"
@@ -1580,7 +1583,7 @@
             -c "client hello, adding pre_shared_key extension, omitting PSK binder list" \
             -c "client hello, adding psk_key_exchange_modes extension" \
             -c "client hello, adding PSK binder list" \
-            -s "No matched PSK or ticket"
+            -s "No usable PSK or ticket"
 
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3
 requires_config_enabled MBEDTLS_SSL_SRV_C
@@ -1665,7 +1668,7 @@
             -c "client hello, adding pre_shared_key extension, omitting PSK binder list" \
             -c "client hello, adding psk_key_exchange_modes extension" \
             -c "client hello, adding PSK binder list" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -s "ClientHello message misses mandatory extensions."
 
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3
@@ -1711,7 +1714,7 @@
             -c "client hello, adding pre_shared_key extension, omitting PSK binder list" \
             -c "client hello, adding psk_key_exchange_modes extension" \
             -c "client hello, adding PSK binder list" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -s "ClientHello message misses mandatory extensions."
 
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3
@@ -1769,7 +1772,7 @@
             -c "client hello, adding pre_shared_key extension, omitting PSK binder list" \
             -c "client hello, adding psk_key_exchange_modes extension" \
             -c "client hello, adding PSK binder list" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -s "ClientHello message misses mandatory extensions."
 
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3
@@ -1827,7 +1830,7 @@
             -c "client hello, adding pre_shared_key extension, omitting PSK binder list" \
             -c "client hello, adding psk_key_exchange_modes extension" \
             -c "client hello, adding PSK binder list" \
-            -s "No matched PSK or ticket"
+            -s "No usable PSK or ticket"
 
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3
 requires_config_enabled MBEDTLS_SSL_SRV_C
@@ -1870,7 +1873,7 @@
             -c "client hello, adding pre_shared_key extension, omitting PSK binder list" \
             -c "client hello, adding psk_key_exchange_modes extension" \
             -c "client hello, adding PSK binder list" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -s "ClientHello message misses mandatory extensions."
 
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3
@@ -1916,7 +1919,7 @@
             -c "client hello, adding pre_shared_key extension, omitting PSK binder list" \
             -c "client hello, adding psk_key_exchange_modes extension" \
             -c "client hello, adding PSK binder list" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
 
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3
 requires_config_enabled MBEDTLS_SSL_SRV_C
@@ -2047,7 +2050,7 @@
             -c "client hello, adding pre_shared_key extension, omitting PSK binder list" \
             -c "client hello, adding psk_key_exchange_modes extension" \
             -c "client hello, adding PSK binder list" \
-            -s "No matched PSK or ticket"
+            -s "No usable PSK or ticket"
 
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3
 requires_config_enabled MBEDTLS_SSL_SRV_C
@@ -2106,7 +2109,7 @@
             -c "client hello, adding pre_shared_key extension, omitting PSK binder list" \
             -c "client hello, adding psk_key_exchange_modes extension" \
             -c "client hello, adding PSK binder list" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -s "key exchange mode: ephemeral"
 
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3
@@ -2152,7 +2155,7 @@
             -c "client hello, adding pre_shared_key extension, omitting PSK binder list" \
             -c "client hello, adding psk_key_exchange_modes extension" \
             -c "client hello, adding PSK binder list" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -s "ClientHello message misses mandatory extensions."
 
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3
@@ -2199,7 +2202,7 @@
             -c "client hello, adding pre_shared_key extension, omitting PSK binder list" \
             -c "client hello, adding psk_key_exchange_modes extension" \
             -c "client hello, adding PSK binder list" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -s "key exchange mode: ephemeral"
 
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3
@@ -2288,7 +2291,7 @@
             -c "client hello, adding pre_shared_key extension, omitting PSK binder list" \
             -c "client hello, adding psk_key_exchange_modes extension" \
             -c "client hello, adding PSK binder list" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -s "ClientHello message misses mandatory extensions."
 
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3
@@ -2348,7 +2351,7 @@
             -c "client hello, adding pre_shared_key extension, omitting PSK binder list" \
             -c "client hello, adding psk_key_exchange_modes extension" \
             -c "client hello, adding PSK binder list" \
-            -s "No matched PSK or ticket"
+            -s "No usable PSK or ticket"
 
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3
 requires_config_enabled MBEDTLS_SSL_SRV_C
@@ -2392,7 +2395,7 @@
             -c "client hello, adding pre_shared_key extension, omitting PSK binder list" \
             -c "client hello, adding psk_key_exchange_modes extension" \
             -c "client hello, adding PSK binder list" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -s "ClientHello message misses mandatory extensions."
 
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3
@@ -2438,7 +2441,7 @@
             -c "client hello, adding pre_shared_key extension, omitting PSK binder list" \
             -c "client hello, adding psk_key_exchange_modes extension" \
             -c "client hello, adding PSK binder list" \
-            -s "No matched PSK or ticket"
+            -s "No usable PSK or ticket"
 
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3
 requires_config_enabled MBEDTLS_SSL_SRV_C
@@ -2485,7 +2488,7 @@
             -c "client hello, adding pre_shared_key extension, omitting PSK binder list" \
             -c "client hello, adding psk_key_exchange_modes extension" \
             -c "client hello, adding PSK binder list" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -s "ClientHello message misses mandatory extensions."
 
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3
@@ -2532,7 +2535,7 @@
             -c "client hello, adding pre_shared_key extension, omitting PSK binder list" \
             -c "client hello, adding psk_key_exchange_modes extension" \
             -c "client hello, adding PSK binder list" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -s "ClientHello message misses mandatory extensions."
 
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3
@@ -2595,7 +2598,7 @@
             -c "client hello, adding pre_shared_key extension, omitting PSK binder list" \
             -c "client hello, adding psk_key_exchange_modes extension" \
             -c "client hello, adding PSK binder list" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -c "Selected key exchange mode: ephemeral" \
             -c "HTTP/1.0 200 OK"
 
@@ -2643,7 +2646,7 @@
             -c "client hello, adding pre_shared_key extension, omitting PSK binder list" \
             -c "client hello, adding psk_key_exchange_modes extension" \
             -c "client hello, adding PSK binder list" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -s "ClientHello message misses mandatory extensions."
 
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3
@@ -2690,7 +2693,7 @@
             -c "client hello, adding pre_shared_key extension, omitting PSK binder list" \
             -c "client hello, adding psk_key_exchange_modes extension" \
             -c "client hello, adding PSK binder list" \
-            -s "No matched PSK or ticket" \
+            -s "No usable PSK or ticket" \
             -s "key exchange mode: ephemeral"
 
 requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3
diff --git a/tests/opt-testcases/tls13-misc.sh b/tests/opt-testcases/tls13-misc.sh
index ad062dc..066fa3f 100755
--- a/tests/opt-testcases/tls13-misc.sh
+++ b/tests/opt-testcases/tls13-misc.sh
@@ -353,8 +353,8 @@
          -s "key exchange mode: ephemeral" \
          -S "key exchange mode: psk_ephemeral" \
          -S "key exchange mode: psk$" \
-         -s "No suitable key exchange mode" \
-         -s "No matched PSK or ticket"
+         -s "No suitable PSK key exchange mode" \
+         -s "No usable PSK or ticket"
 
 requires_all_configs_enabled MBEDTLS_SSL_SESSION_TICKETS \
                              MBEDTLS_SSL_SRV_C MBEDTLS_SSL_CLI_C MBEDTLS_DEBUG_C \
@@ -365,7 +365,7 @@
          "$P_CLI debug_level=4 tls13_kex_modes=psk_or_ephemeral reconnect=1" \
          0 \
          -c "Pre-configured PSK number = 1" \
-         -S "No suitable key exchange mode" \
+         -S "No suitable PSK key exchange mode" \
          -s "found matched identity"
 
 requires_all_configs_enabled MBEDTLS_SSL_SESSION_TICKETS \
@@ -381,8 +381,8 @@
          -s "key exchange mode: ephemeral" \
          -S "key exchange mode: psk_ephemeral" \
          -S "key exchange mode: psk$" \
-         -s "No suitable key exchange mode" \
-         -s "No matched PSK or ticket"
+         -s "No suitable PSK key exchange mode" \
+         -s "No usable PSK or ticket"
 
 requires_all_configs_enabled MBEDTLS_SSL_SESSION_TICKETS \
                              MBEDTLS_SSL_SRV_C MBEDTLS_SSL_CLI_C MBEDTLS_DEBUG_C \
@@ -393,7 +393,7 @@
          "$P_CLI debug_level=4 tls13_kex_modes=psk_or_ephemeral reconnect=1" \
          0 \
          -c "Pre-configured PSK number = 1" \
-         -S "No suitable key exchange mode" \
+         -S "No suitable PSK key exchange mode" \
          -s "found matched identity"
 
 requires_all_configs_enabled MBEDTLS_SSL_SESSION_TICKETS \
@@ -409,8 +409,8 @@
          -s "key exchange mode: ephemeral" \
          -S "key exchange mode: psk_ephemeral" \
          -S "key exchange mode: psk$" \
-         -s "No suitable key exchange mode" \
-         -s "No matched PSK or ticket"
+         -s "No suitable PSK key exchange mode" \
+         -s "No usable PSK or ticket"
 
 requires_all_configs_enabled MBEDTLS_SSL_SESSION_TICKETS \
                              MBEDTLS_SSL_SRV_C MBEDTLS_SSL_CLI_C MBEDTLS_DEBUG_C \
@@ -425,8 +425,8 @@
          -s "key exchange mode: ephemeral" \
          -S "key exchange mode: psk_ephemeral" \
          -S "key exchange mode: psk$" \
-         -s "No suitable key exchange mode" \
-         -s "No matched PSK or ticket"
+         -s "No suitable PSK key exchange mode" \
+         -s "No usable PSK or ticket"
 
 requires_all_configs_enabled MBEDTLS_SSL_SESSION_TICKETS \
                              MBEDTLS_SSL_SRV_C MBEDTLS_SSL_CLI_C MBEDTLS_DEBUG_C \
@@ -437,7 +437,7 @@
          "$P_CLI debug_level=4 tls13_kex_modes=ephemeral_all reconnect=1" \
          0 \
          -c "Pre-configured PSK number = 1" \
-         -S "No suitable key exchange mode" \
+         -S "No suitable PSK key exchange mode" \
          -s "found matched identity" \
          -s "key exchange mode: psk_ephemeral"
 
@@ -450,7 +450,7 @@
          "$P_CLI debug_level=4 tls13_kex_modes=ephemeral_all reconnect=1" \
          0 \
          -c "Pre-configured PSK number = 1" \
-         -S "No suitable key exchange mode" \
+         -S "No suitable PSK key exchange mode" \
          -s "found matched identity" \
          -s "key exchange mode: psk_ephemeral"
 
@@ -468,8 +468,8 @@
          -s "key exchange mode: ephemeral" \
          -S "key exchange mode: psk_ephemeral" \
          -S "key exchange mode: psk$" \
-         -s "No suitable key exchange mode" \
-         -s "No matched PSK or ticket"
+         -s "No suitable PSK key exchange mode" \
+         -s "No usable PSK or ticket"
 
 requires_all_configs_enabled MBEDTLS_SSL_SESSION_TICKETS \
                              MBEDTLS_SSL_SRV_C MBEDTLS_SSL_CLI_C MBEDTLS_DEBUG_C \
@@ -481,7 +481,7 @@
          "$P_CLI debug_level=4 tls13_kex_modes=all reconnect=1" \
          0 \
          -c "Pre-configured PSK number = 1" \
-         -S "No suitable key exchange mode" \
+         -S "No suitable PSK key exchange mode" \
          -s "found matched identity"
 
 requires_all_configs_enabled MBEDTLS_SSL_SESSION_TICKETS \
@@ -494,7 +494,7 @@
          "$P_CLI debug_level=4 tls13_kex_modes=all reconnect=1" \
          0 \
          -c "Pre-configured PSK number = 1" \
-         -S "No suitable key exchange mode" \
+         -S "No suitable PSK key exchange mode" \
          -s "found matched identity" \
          -s "key exchange mode: psk_ephemeral"
 
@@ -508,7 +508,7 @@
          "$P_CLI debug_level=4 tls13_kex_modes=all reconnect=1" \
          0 \
          -c "Pre-configured PSK number = 1" \
-         -S "No suitable key exchange mode" \
+         -S "No suitable PSK key exchange mode" \
          -s "found matched identity" \
          -s "key exchange mode: psk_ephemeral"
 
@@ -535,3 +535,18 @@
          -s "$( tail -1 $EARLY_DATA_INPUT )"                                \
          -s "200 early data bytes read"                                     \
          -s "106 early data bytes read"
+
+requires_all_configs_enabled MBEDTLS_SSL_EARLY_DATA MBEDTLS_SSL_SESSION_TICKETS \
+                             MBEDTLS_SSL_CLI_C MBEDTLS_SSL_SRV_C \
+                             MBEDTLS_DEBUG_C MBEDTLS_HAVE_TIME \
+                             MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_ENABLED \
+                             MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL_ENABLED
+run_test "TLS 1.3 m->m: Ephemeral over PSK kex with early data enabled" \
+         "$P_SRV force_version=tls13 debug_level=4 max_early_data_size=1024" \
+         "$P_CLI debug_level=4 early_data=1 tls13_kex_modes=psk_or_ephemeral reco_mode=1 reconnect=1" \
+         0 \
+         -s "key exchange mode: ephemeral" \
+         -S "key exchange mode: psk" \
+         -s "found matched identity" \
+         -s "EarlyData: rejected, not a session resumption" \
+         -C "EncryptedExtensions: early_data(42) extension exists."
diff --git a/tests/src/psa_crypto_stubs.c b/tests/src/psa_crypto_stubs.c
new file mode 100644
index 0000000..f3ca850
--- /dev/null
+++ b/tests/src/psa_crypto_stubs.c
@@ -0,0 +1,25 @@
+/** \file psa_crypto_stubs.c
+ *
+ * \brief Stub functions when MBEDTLS_PSA_CRYPTO_CLIENT is enabled but
+ *        MBEDTLS_PSA_CRYPTO_C is disabled.
+ */
+
+/*
+ *  Copyright The Mbed TLS Contributors
+ *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
+ */
+
+#include <psa/crypto.h>
+
+#if defined(MBEDTLS_PSA_CRYPTO_CLIENT) && !defined(MBEDTLS_PSA_CRYPTO_C)
+
+psa_status_t psa_generate_random(uint8_t *output,
+                                 size_t output_size)
+{
+    (void) output;
+    (void) output_size;
+
+    return PSA_ERROR_COMMUNICATION_FAILURE;
+}
+
+#endif /* MBEDTLS_PSA_CRYPTO_CLIENT && !MBEDTLS_PSA_CRYPTO_C */
diff --git a/tests/src/test_helpers/ssl_helpers.c b/tests/src/test_helpers/ssl_helpers.c
index 5d4cb1c..56e03f1 100644
--- a/tests/src/test_helpers/ssl_helpers.c
+++ b/tests/src/test_helpers/ssl_helpers.c
@@ -12,9 +12,7 @@
 #include "mbedtls/psa_util.h"
 
 #if defined(MBEDTLS_SSL_TLS_C)
-#if defined(MBEDTLS_SSL_HANDSHAKE_WITH_CERT_ENABLED)
-static int rng_seed = 0xBEEF;
-static int rng_get(void *p_rng, unsigned char *output, size_t output_len)
+int mbedtls_test_random(void *p_rng, unsigned char *output, size_t output_len)
 {
     (void) p_rng;
     for (size_t i = 0; i < output_len; i++) {
@@ -23,7 +21,6 @@
 
     return 0;
 }
-#endif
 
 void mbedtls_test_ssl_log_analyzer(void *ctx, int level,
                                    const char *file, int line,
@@ -46,6 +43,8 @@
     mbedtls_test_handshake_test_options *opts)
 {
 #if defined(MBEDTLS_SSL_HANDSHAKE_WITH_CERT_ENABLED)
+    static int rng_seed = 0xBEEF;
+
     srand(rng_seed);
     rng_seed += 0xD0;
 #endif
@@ -68,6 +67,7 @@
     opts->legacy_renegotiation = MBEDTLS_SSL_LEGACY_NO_RENEGOTIATION;
     opts->resize_buffers = 1;
     opts->early_data = MBEDTLS_SSL_EARLY_DATA_DISABLED;
+    opts->max_early_data_size = -1;
 #if defined(MBEDTLS_SSL_CACHE_C)
     TEST_CALLOC(opts->cache, 1);
     mbedtls_ssl_cache_init(opts->cache);
@@ -755,7 +755,7 @@
 
     mbedtls_ssl_init(&(ep->ssl));
     mbedtls_ssl_config_init(&(ep->conf));
-    mbedtls_ssl_conf_rng(&(ep->conf), rng_get, NULL);
+    mbedtls_ssl_conf_rng(&(ep->conf), mbedtls_test_random, NULL);
 
     TEST_ASSERT(mbedtls_ssl_conf_get_user_data_p(&ep->conf) == NULL);
     TEST_EQUAL(mbedtls_ssl_conf_get_user_data_n(&ep->conf), 0);
@@ -826,6 +826,13 @@
 
 #if defined(MBEDTLS_SSL_EARLY_DATA)
     mbedtls_ssl_conf_early_data(&(ep->conf), options->early_data);
+#if defined(MBEDTLS_SSL_SRV_C)
+    if (endpoint_type == MBEDTLS_SSL_IS_SERVER &&
+        (options->max_early_data_size >= 0)) {
+        mbedtls_ssl_conf_max_early_data_size(&(ep->conf),
+                                             options->max_early_data_size);
+    }
+#endif
 #endif
 
 #if defined(MBEDTLS_SSL_CACHE_C) && defined(MBEDTLS_SSL_SRV_C)
diff --git a/tests/suites/test_suite_bignum.function b/tests/suites/test_suite_bignum.function
index 50be2d2..f3a64e1 100644
--- a/tests/suites/test_suite_bignum.function
+++ b/tests/suites/test_suite_bignum.function
@@ -966,6 +966,45 @@
 /* END_CASE */
 
 /* BEGIN_CASE */
+void mpi_exp_mod_min_RR(char *input_A, char *input_E,
+                        char *input_N, char *input_X,
+                        int exp_result)
+{
+    mbedtls_mpi A, E, N, RR, Z, X;
+    int res;
+    mbedtls_mpi_init(&A); mbedtls_mpi_init(&E); mbedtls_mpi_init(&N);
+    mbedtls_mpi_init(&RR); mbedtls_mpi_init(&Z); mbedtls_mpi_init(&X);
+
+    TEST_EQUAL(mbedtls_test_read_mpi(&A, input_A), 0);
+    TEST_EQUAL(mbedtls_test_read_mpi(&E, input_E), 0);
+    TEST_EQUAL(mbedtls_test_read_mpi(&N, input_N), 0);
+    TEST_EQUAL(mbedtls_test_read_mpi(&X, input_X), 0);
+
+    TEST_EQUAL(mbedtls_mpi_core_get_mont_r2_unsafe(&RR, &N), 0);
+    TEST_EQUAL(mbedtls_mpi_shrink(&RR, 0), 0);
+    /* The objective of this test is to check that exp_mod defends
+     * against a smaller RR. */
+    TEST_LE_U(RR.n, N.n - 1);
+
+    res = mbedtls_mpi_exp_mod(&Z, &A, &E, &N, &RR);
+    /* We know that exp_mod internally needs RR to be as large as N.
+     * Validate that it is the case now, otherwise there was probably
+     * a buffer overread. */
+    TEST_EQUAL(RR.n, N.n);
+
+    TEST_EQUAL(res, exp_result);
+    if (res == 0) {
+        TEST_EQUAL(sign_is_valid(&Z), 1);
+        TEST_EQUAL(mbedtls_mpi_cmp_mpi(&Z, &X), 0);
+    }
+
+exit:
+    mbedtls_mpi_free(&A); mbedtls_mpi_free(&E); mbedtls_mpi_free(&N);
+    mbedtls_mpi_free(&RR); mbedtls_mpi_free(&Z); mbedtls_mpi_free(&X);
+}
+/* END_CASE */
+
+/* BEGIN_CASE */
 void mpi_exp_mod(char *input_A, char *input_E,
                  char *input_N, char *input_X,
                  int exp_result)
diff --git a/tests/suites/test_suite_bignum.misc.data b/tests/suites/test_suite_bignum.misc.data
index c53e42a..eb55dbe 100644
--- a/tests/suites/test_suite_bignum.misc.data
+++ b/tests/suites/test_suite_bignum.misc.data
@@ -1362,6 +1362,9 @@
 Test mbedtls_mpi_exp_mod: 10 ^ 0 (1 limb) mod 9
 mpi_exp_mod:"0a":"00":"09":"1":0
 
+Test mbedtls_mpi_exp_mod: -3 ^ 3 mod 27
+mpi_exp_mod:"-3":"3":"1b":"1b":0
+
 Test mbedtls_mpi_exp_mod: MAX_SIZE exponent
 mpi_exp_mod_size:2:MBEDTLS_MPI_MAX_SIZE:10:"":0
 
@@ -1391,6 +1394,14 @@
 depends_on:MPI_MAX_BITS_LARGER_THAN_792
 mpi_exp_mod:"-9f13012cd92aa72fb86ac8879d2fde4f7fd661aaae43a00971f081cc60ca277059d5c37e89652e2af2585d281d66ef6a9d38a117e9608e9e7574cd142dc55278838a2161dd56db9470d4c1da2d5df15a908ee2eb886aaa890f23be16de59386663a12f1afbb325431a3e835e3fd89b98b96a6f77382f458ef9a37e1f84a03045c8676ab55291a94c2228ea15448ee96b626b998":"40a54d1b9e86789f06d9607fb158672d64867665c73ee9abb545fc7a785634b354c7bae5b962ce8040cf45f2c1f3d3659b2ee5ede17534c8fc2ec85c815e8df1fe7048d12c90ee31b88a68a081f17f0d8ce5f4030521e9400083bcea73a429031d4ca7949c2000d597088e0c39a6014d8bf962b73bb2e8083bd0390a4e00b9b3":"eeaf0ab9adb38dd69c33f80afa8fc5e86072618775ff3c0b9ea2314c9c256576d674df7496ea81d3383b4813d692c6e0e0d5d8e250b98be48e495c1d6089dad15dc7d7b46154d6b6ce8ef4ad69b15d4982559b297bcf1885c529f566660e57ec68edbc3c05726cc02fd4cbf4976eaa9afd5138fe8376435b9fc61d2fc0eb06e3":"21acc7199e1b90f9b4844ffe12c19f00ec548c5d32b21c647d48b6015d8eb9ec9db05b4f3d44db4227a2b5659c1a7cceb9d5fa8fa60376047953ce7397d90aaeb7465e14e820734f84aa52ad0fc66701bcbb991d57715806a11531268e1e83dd48288c72b424a6287e9ce4e5cc4db0dd67614aecc23b0124a5776d36e5c89483":0
 
+Test mbedtls_mpi_exp_mod (N.n=3, RR.n=1 on 32 bit)
+depends_on:MBEDTLS_HAVE_INT32
+mpi_exp_mod_min_RR:"10":"2":"10000000100000001":"100":0
+
+Test mbedtls_mpi_exp_mod (N.n=3, RR.n=1 on 64 bit)
+depends_on:MBEDTLS_HAVE_INT64
+mpi_exp_mod_min_RR:"10":"2":"100000000000000010000000000000001":"100":0
+
 Base test GCD #1
 mpi_gcd:"2b5":"261":"15"
 
diff --git a/tests/suites/test_suite_debug.function b/tests/suites/test_suite_debug.function
index eeefc95..70e7bad 100644
--- a/tests/suites/test_suite_debug.function
+++ b/tests/suites/test_suite_debug.function
@@ -2,6 +2,7 @@
 #include "debug_internal.h"
 #include "string.h"
 #include "mbedtls/pk.h"
+#include <test/ssl_helpers.h>
 
 struct buffer_data {
     char buf[2000];
@@ -65,11 +66,12 @@
     memset(buffer.buf, 0, 2000);
     buffer.ptr = buffer.buf;
 
-    mbedtls_ssl_config_defaults(&conf,
-                                MBEDTLS_SSL_IS_CLIENT,
-                                MBEDTLS_SSL_TRANSPORT_STREAM,
-                                MBEDTLS_SSL_PRESET_DEFAULT);
-
+    TEST_EQUAL(mbedtls_ssl_config_defaults(&conf,
+                                           MBEDTLS_SSL_IS_CLIENT,
+                                           MBEDTLS_SSL_TRANSPORT_STREAM,
+                                           MBEDTLS_SSL_PRESET_DEFAULT),
+               0);
+    mbedtls_ssl_conf_rng(&conf, mbedtls_test_random, NULL);
     mbedtls_ssl_conf_dbg(&conf, string_debug, &buffer);
 
     TEST_ASSERT(mbedtls_ssl_setup(&ssl, &conf) == 0);
@@ -103,11 +105,12 @@
     memset(buffer.buf, 0, 2000);
     buffer.ptr = buffer.buf;
 
-    mbedtls_ssl_config_defaults(&conf,
-                                MBEDTLS_SSL_IS_CLIENT,
-                                MBEDTLS_SSL_TRANSPORT_STREAM,
-                                MBEDTLS_SSL_PRESET_DEFAULT);
-
+    TEST_EQUAL(mbedtls_ssl_config_defaults(&conf,
+                                           MBEDTLS_SSL_IS_CLIENT,
+                                           MBEDTLS_SSL_TRANSPORT_STREAM,
+                                           MBEDTLS_SSL_PRESET_DEFAULT),
+               0);
+    mbedtls_ssl_conf_rng(&conf, mbedtls_test_random, NULL);
     mbedtls_ssl_conf_dbg(&conf, string_debug, &buffer);
 
     TEST_ASSERT(mbedtls_ssl_setup(&ssl, &conf) == 0);
@@ -138,11 +141,12 @@
     memset(buffer.buf, 0, 2000);
     buffer.ptr = buffer.buf;
 
-    mbedtls_ssl_config_defaults(&conf,
-                                MBEDTLS_SSL_IS_CLIENT,
-                                MBEDTLS_SSL_TRANSPORT_STREAM,
-                                MBEDTLS_SSL_PRESET_DEFAULT);
-
+    TEST_EQUAL(mbedtls_ssl_config_defaults(&conf,
+                                           MBEDTLS_SSL_IS_CLIENT,
+                                           MBEDTLS_SSL_TRANSPORT_STREAM,
+                                           MBEDTLS_SSL_PRESET_DEFAULT),
+               0);
+    mbedtls_ssl_conf_rng(&conf, mbedtls_test_random, NULL);
     mbedtls_ssl_conf_dbg(&conf, string_debug, &buffer);
 
     TEST_ASSERT(mbedtls_ssl_setup(&ssl, &conf) == 0);
@@ -175,11 +179,12 @@
     memset(buffer.buf, 0, 2000);
     buffer.ptr = buffer.buf;
 
-    mbedtls_ssl_config_defaults(&conf,
-                                MBEDTLS_SSL_IS_CLIENT,
-                                MBEDTLS_SSL_TRANSPORT_STREAM,
-                                MBEDTLS_SSL_PRESET_DEFAULT);
-
+    TEST_EQUAL(mbedtls_ssl_config_defaults(&conf,
+                                           MBEDTLS_SSL_IS_CLIENT,
+                                           MBEDTLS_SSL_TRANSPORT_STREAM,
+                                           MBEDTLS_SSL_PRESET_DEFAULT),
+               0);
+    mbedtls_ssl_conf_rng(&conf, mbedtls_test_random, NULL);
     mbedtls_ssl_conf_dbg(&conf, string_debug, &buffer);
 
     TEST_ASSERT(mbedtls_ssl_setup(&ssl, &conf) == 0);
@@ -214,11 +219,12 @@
     memset(buffer.buf, 0, 2000);
     buffer.ptr = buffer.buf;
 
-    mbedtls_ssl_config_defaults(&conf,
-                                MBEDTLS_SSL_IS_CLIENT,
-                                MBEDTLS_SSL_TRANSPORT_STREAM,
-                                MBEDTLS_SSL_PRESET_DEFAULT);
-
+    TEST_EQUAL(mbedtls_ssl_config_defaults(&conf,
+                                           MBEDTLS_SSL_IS_CLIENT,
+                                           MBEDTLS_SSL_TRANSPORT_STREAM,
+                                           MBEDTLS_SSL_PRESET_DEFAULT),
+               0);
+    mbedtls_ssl_conf_rng(&conf, mbedtls_test_random, NULL);
     mbedtls_ssl_conf_dbg(&conf, string_debug, &buffer);
 
     TEST_ASSERT(mbedtls_ssl_setup(&ssl, &conf) == 0);
diff --git a/tests/suites/test_suite_ssl.data b/tests/suites/test_suite_ssl.data
index 385682a..c0c816c 100644
--- a/tests/suites/test_suite_ssl.data
+++ b/tests/suites/test_suite_ssl.data
@@ -3309,3 +3309,39 @@
 
 TLS 1.3 write early data, hello retry request
 tls13_write_early_data:TEST_EARLY_DATA_HRR
+
+TLS 1.3 srv, max early data size, dflt, wsz=96
+tls13_srv_max_early_data_size:TEST_EARLY_DATA_ACCEPTED:-1:96
+
+TLS 1.3 srv, max early data size, dflt, wsz=128
+tls13_srv_max_early_data_size:TEST_EARLY_DATA_ACCEPTED:-1:128
+
+TLS 1.3 srv, max early data size, 3, wsz=2
+tls13_srv_max_early_data_size:TEST_EARLY_DATA_ACCEPTED:3:2
+
+TLS 1.3 srv, max early data size, 3, wsz=3
+tls13_srv_max_early_data_size:TEST_EARLY_DATA_ACCEPTED:3:3
+
+TLS 1.3 srv, max early data size, 98, wsz=23
+tls13_srv_max_early_data_size:TEST_EARLY_DATA_ACCEPTED:98:23
+
+TLS 1.3 srv, max early data size, 98, wsz=49
+tls13_srv_max_early_data_size:TEST_EARLY_DATA_ACCEPTED:98:49
+
+TLS 1.3 srv, max early data size, server rejects, dflt, wsz=128
+tls13_srv_max_early_data_size:TEST_EARLY_DATA_SERVER_REJECTS:-1:128
+
+TLS 1.3 srv, max early data size, server rejects, 3, wsz=3
+tls13_srv_max_early_data_size:TEST_EARLY_DATA_SERVER_REJECTS:3:3
+
+TLS 1.3 srv, max early data size, server rejects, 98, wsz=49
+tls13_srv_max_early_data_size:TEST_EARLY_DATA_SERVER_REJECTS:98:49
+
+TLS 1.3 srv, max early data size, HRR, dflt, wsz=128
+tls13_srv_max_early_data_size:TEST_EARLY_DATA_HRR:-1:128
+
+TLS 1.3 srv, max early data size, HRR, 3, wsz=3
+tls13_srv_max_early_data_size:TEST_EARLY_DATA_HRR:3:3
+
+TLS 1.3 srv, max early data size, HRR, 98, wsz=49
+tls13_srv_max_early_data_size:TEST_EARLY_DATA_HRR:97:0
diff --git a/tests/suites/test_suite_ssl.function b/tests/suites/test_suite_ssl.function
index d327828..6e95817 100644
--- a/tests/suites/test_suite_ssl.function
+++ b/tests/suites/test_suite_ssl.function
@@ -18,6 +18,47 @@
 #define TEST_EARLY_DATA_SERVER_REJECTS 2
 #define TEST_EARLY_DATA_HRR 3
 
+#if (!defined(MBEDTLS_SSL_PROTO_TLS1_2)) && \
+    defined(MBEDTLS_SSL_EARLY_DATA) && defined(MBEDTLS_SSL_CLI_C) && \
+    defined(MBEDTLS_SSL_SRV_C) && defined(MBEDTLS_DEBUG_C) && \
+    defined(MBEDTLS_TEST_AT_LEAST_ONE_TLS1_3_CIPHERSUITE) && \
+    defined(MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL_ENABLED) && \
+    defined(MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL_ENABLED) && \
+    defined(MBEDTLS_MD_CAN_SHA256) && \
+    defined(MBEDTLS_ECP_HAVE_SECP256R1) && defined(MBEDTLS_ECP_HAVE_SECP384R1) && \
+    defined(MBEDTLS_PK_CAN_ECDSA_VERIFY) && defined(MBEDTLS_SSL_SESSION_TICKETS)
+/*
+ * Test function to write early data for negative tests where
+ * mbedtls_ssl_write_early_data() cannot be used.
+ */
+static int write_early_data(mbedtls_ssl_context *ssl,
+                            unsigned char *buf, size_t len)
+{
+    int ret = mbedtls_ssl_get_max_out_record_payload(ssl);
+
+    TEST_ASSERT(ret > 0);
+    TEST_LE_U(len, (size_t) ret);
+
+    ret = mbedtls_ssl_flush_output(ssl);
+    TEST_EQUAL(ret, 0);
+    TEST_EQUAL(ssl->out_left, 0);
+
+    ssl->out_msglen = len;
+    ssl->out_msgtype = MBEDTLS_SSL_MSG_APPLICATION_DATA;
+    if (len > 0) {
+        memcpy(ssl->out_msg, buf, len);
+    }
+
+    ret = mbedtls_ssl_write_record(ssl, 1);
+    TEST_EQUAL(ret, 0);
+
+    ret = len;
+
+exit:
+    return ret;
+}
+#endif
+
 /* END_HEADER */
 
 /* BEGIN_DEPENDENCIES
@@ -1131,6 +1172,8 @@
                                             MBEDTLS_SSL_IS_CLIENT,
                                             MBEDTLS_SSL_TRANSPORT_DATAGRAM,
                                             MBEDTLS_SSL_PRESET_DEFAULT) == 0);
+    mbedtls_ssl_conf_rng(&conf, mbedtls_test_random, NULL);
+
     TEST_ASSERT(mbedtls_ssl_setup(&ssl, &conf) == 0);
 
     /* Read previous record numbers */
@@ -2879,6 +2922,7 @@
     mbedtls_ssl_conf_transport(&conf, transport);
     mbedtls_ssl_conf_min_tls_version(&conf, min_tls_version);
     mbedtls_ssl_conf_max_tls_version(&conf, max_tls_version);
+    mbedtls_ssl_conf_rng(&conf, mbedtls_test_random, NULL);
 
     TEST_ASSERT(mbedtls_ssl_setup(&ssl, &conf) == expected_ssl_setup_result);
     TEST_EQUAL(mbedtls_ssl_conf_get_endpoint(
@@ -2920,6 +2964,8 @@
     mbedtls_ssl_init(&ssl);
     MD_OR_USE_PSA_INIT();
 
+    mbedtls_ssl_conf_rng(&conf, mbedtls_test_random, NULL);
+
     TEST_ASSERT(mbedtls_ssl_setup(&ssl, &conf) == 0);
 
     TEST_ASSERT(ssl.handshake != NULL && ssl.handshake->group_list != NULL);
@@ -2951,6 +2997,7 @@
     mbedtls_ssl_config conf;
     mbedtls_ssl_config_init(&conf);
 
+    mbedtls_ssl_conf_rng(&conf, mbedtls_test_random, NULL);
     mbedtls_ssl_conf_max_tls_version(&conf, MBEDTLS_SSL_VERSION_TLS1_2);
     mbedtls_ssl_conf_min_tls_version(&conf, MBEDTLS_SSL_VERSION_TLS1_2);
 
@@ -3059,6 +3106,7 @@
                                            MBEDTLS_SSL_TRANSPORT_DATAGRAM,
                                            MBEDTLS_SSL_PRESET_DEFAULT),
                0);
+    mbedtls_ssl_conf_rng(&conf, mbedtls_test_random, NULL);
 
     TEST_EQUAL(mbedtls_ssl_setup(&ssl, &conf), 0);
     TEST_EQUAL(mbedtls_ssl_check_dtls_clihlo_cookie(&ssl, ssl.cli_id,
@@ -3113,6 +3161,7 @@
                                             MBEDTLS_SSL_TRANSPORT_STREAM,
                                             MBEDTLS_SSL_PRESET_DEFAULT)
                 == 0);
+    mbedtls_ssl_conf_rng(&conf, mbedtls_test_random, NULL);
 
     TEST_ASSERT(mbedtls_ssl_setup(&ssl, &conf) == 0);
 
@@ -3371,6 +3420,7 @@
                                            MBEDTLS_SSL_IS_CLIENT,
                                            MBEDTLS_SSL_TRANSPORT_STREAM,
                                            MBEDTLS_SSL_PRESET_DEFAULT), 0);
+    mbedtls_ssl_conf_rng(&conf, mbedtls_test_random, NULL);
 
     TEST_EQUAL(mbedtls_ssl_setup(&ssl, &conf), 0);
 
@@ -4159,6 +4209,10 @@
             break;
 
         case TEST_EARLY_DATA_HRR:
+            /*
+             * Remove server support for the group negotiated in
+             * mbedtls_test_get_tls13_ticket() forcing a HelloRetryRequest.
+             */
             server_options.group_list = group_list + 1;
             break;
 
@@ -4448,3 +4502,259 @@
     PSA_DONE();
 }
 /* END_CASE */
+
+/*
+ * The !MBEDTLS_SSL_PROTO_TLS1_2 dependency of tls13_early_data() below is
+ * a temporary workaround to not run the test in Windows-2013 where there is
+ * an issue with mbedtls_vsnprintf().
+ */
+/* BEGIN_CASE depends_on:!MBEDTLS_SSL_PROTO_TLS1_2:MBEDTLS_SSL_EARLY_DATA:MBEDTLS_SSL_CLI_C:MBEDTLS_SSL_SRV_C:MBEDTLS_DEBUG_C:MBEDTLS_TEST_AT_LEAST_ONE_TLS1_3_CIPHERSUITE:MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL_ENABLED:MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL_ENABLED:MBEDTLS_MD_CAN_SHA256:MBEDTLS_ECP_HAVE_SECP256R1:MBEDTLS_ECP_HAVE_SECP384R1:MBEDTLS_PK_CAN_ECDSA_VERIFY:MBEDTLS_SSL_SESSION_TICKETS */
+void tls13_srv_max_early_data_size(int scenario, int max_early_data_size_arg, int write_size_arg)
+{
+    int ret = -1;
+    mbedtls_test_ssl_endpoint client_ep, server_ep;
+    mbedtls_test_handshake_test_options client_options;
+    mbedtls_test_handshake_test_options server_options;
+    mbedtls_ssl_session saved_session;
+    mbedtls_test_ssl_log_pattern server_pattern = { NULL, 0 };
+    uint16_t group_list[3] = {
+        MBEDTLS_SSL_IANA_TLS_GROUP_SECP256R1,
+        MBEDTLS_SSL_IANA_TLS_GROUP_SECP384R1,
+        MBEDTLS_SSL_IANA_TLS_GROUP_NONE
+    };
+    char pattern[128];
+    unsigned char *buf_write = NULL;
+    uint32_t write_size = (uint32_t) write_size_arg;
+    unsigned char *buf_read = NULL;
+    uint32_t read_size;
+    uint32_t expanded_early_data_chunk_size = 0;
+    uint32_t written_early_data_size = 0;
+    uint32_t max_early_data_size;
+
+    mbedtls_platform_zeroize(&client_ep, sizeof(client_ep));
+    mbedtls_platform_zeroize(&server_ep, sizeof(server_ep));
+    mbedtls_test_init_handshake_options(&client_options);
+    mbedtls_test_init_handshake_options(&server_options);
+    mbedtls_ssl_session_init(&saved_session);
+    PSA_INIT();
+
+    TEST_CALLOC(buf_write, write_size);
+
+    /*
+     * Allocate a smaller buffer for early data reading to exercise the reading
+     * of data in one record in multiple calls.
+     */
+    read_size = (write_size / 2) + 1;
+    TEST_CALLOC(buf_read, read_size);
+
+    /*
+     * Run first handshake to get a ticket from the server.
+     */
+
+    client_options.pk_alg = MBEDTLS_PK_ECDSA;
+    client_options.group_list = group_list;
+    client_options.early_data = MBEDTLS_SSL_EARLY_DATA_ENABLED;
+    server_options.pk_alg = MBEDTLS_PK_ECDSA;
+    server_options.group_list = group_list;
+    server_options.early_data = MBEDTLS_SSL_EARLY_DATA_ENABLED;
+    server_options.max_early_data_size = max_early_data_size_arg;
+
+    ret = mbedtls_test_get_tls13_ticket(&client_options, &server_options,
+                                        &saved_session);
+    TEST_EQUAL(ret, 0);
+
+    /*
+     * Prepare for handshake with the ticket.
+     */
+    server_options.srv_log_fun = mbedtls_test_ssl_log_analyzer;
+    server_options.srv_log_obj = &server_pattern;
+    server_pattern.pattern = pattern;
+
+    switch (scenario) {
+        case TEST_EARLY_DATA_ACCEPTED:
+            break;
+
+        case TEST_EARLY_DATA_SERVER_REJECTS:
+            server_options.early_data = MBEDTLS_SSL_EARLY_DATA_DISABLED;
+            ret = mbedtls_snprintf(pattern, sizeof(pattern),
+                                   "EarlyData: deprotect and discard app data records.");
+            TEST_ASSERT(ret < (int) sizeof(pattern));
+            mbedtls_debug_set_threshold(3);
+            break;
+
+        case TEST_EARLY_DATA_HRR:
+            /*
+             * Remove server support for the group negotiated in
+             * mbedtls_test_get_tls13_ticket() forcing an HelloRetryRequest.
+             */
+            server_options.group_list = group_list + 1;
+            ret = mbedtls_snprintf(
+                pattern, sizeof(pattern),
+                "EarlyData: Ignore application message before 2nd ClientHello");
+            TEST_ASSERT(ret < (int) sizeof(pattern));
+            mbedtls_debug_set_threshold(3);
+            break;
+
+        default:
+            TEST_FAIL("Unknown scenario.");
+    }
+
+    ret = mbedtls_test_ssl_endpoint_init(&client_ep, MBEDTLS_SSL_IS_CLIENT,
+                                         &client_options, NULL, NULL, NULL);
+    TEST_EQUAL(ret, 0);
+
+    ret = mbedtls_test_ssl_endpoint_init(&server_ep, MBEDTLS_SSL_IS_SERVER,
+                                         &server_options, NULL, NULL, NULL);
+    TEST_EQUAL(ret, 0);
+
+    mbedtls_ssl_conf_session_tickets_cb(&server_ep.conf,
+                                        mbedtls_test_ticket_write,
+                                        mbedtls_test_ticket_parse,
+                                        NULL);
+
+    ret = mbedtls_test_mock_socket_connect(&(client_ep.socket),
+                                           &(server_ep.socket), 1024);
+    TEST_EQUAL(ret, 0);
+
+    max_early_data_size = saved_session.max_early_data_size;
+
+    ret = mbedtls_ssl_set_session(&(client_ep.ssl), &saved_session);
+    TEST_EQUAL(ret, 0);
+
+    /*
+     * Start an handshake based on the ticket up to the point where early data
+     * can be sent from client side. Then send in a loop as much early data as
+     * possible without going over the maximum permitted size for the ticket.
+     * Finally, do a last writting to go past that maximum permitted size and
+     * check that we detect it.
+     */
+    TEST_EQUAL(mbedtls_test_move_handshake_to_state(
+                   &(client_ep.ssl), &(server_ep.ssl),
+                   MBEDTLS_SSL_SERVER_HELLO), 0);
+
+    TEST_ASSERT(client_ep.ssl.early_data_status !=
+                MBEDTLS_SSL_EARLY_DATA_STATUS_NOT_SENT);
+
+    ret = mbedtls_ssl_handshake(&(server_ep.ssl));
+    TEST_EQUAL(ret, MBEDTLS_ERR_SSL_WANT_READ);
+
+    /*
+     * Write and if possible read as much as possible chunks of write_size
+     * bytes data without getting over the max_early_data_size limit.
+     */
+    do {
+        uint32_t read_early_data_size = 0;
+
+        /*
+         * The contents of the early data are not very important, write a
+         * pattern that varies byte-by-byte and is different for every chunk of
+         * early data.
+         */
+        if ((written_early_data_size + write_size) > max_early_data_size) {
+            break;
+        }
+
+        /*
+         * If the server rejected early data, base the determination of when
+         * to stop the loop on the expanded size (padding and encryption
+         * expansion) of early data on server side and the number of early data
+         * received so far by the server (multiple of the expanded size).
+         */
+        if ((expanded_early_data_chunk_size != 0) &&
+            ((server_ep.ssl.total_early_data_size +
+              expanded_early_data_chunk_size) > max_early_data_size)) {
+            break;
+        }
+
+        for (size_t i = 0; i < write_size; i++) {
+            buf_write[i] = (unsigned char) (written_early_data_size + i);
+        }
+
+        ret = write_early_data(&(client_ep.ssl), buf_write, write_size);
+        TEST_EQUAL(ret, write_size);
+        written_early_data_size += write_size;
+
+        switch (scenario) {
+            case TEST_EARLY_DATA_ACCEPTED:
+                while (read_early_data_size < write_size) {
+                    ret = mbedtls_ssl_handshake(&(server_ep.ssl));
+                    TEST_EQUAL(ret, MBEDTLS_ERR_SSL_RECEIVED_EARLY_DATA);
+
+                    ret = mbedtls_ssl_read_early_data(&(server_ep.ssl),
+                                                      buf_read, read_size);
+                    TEST_ASSERT(ret > 0);
+
+                    TEST_MEMORY_COMPARE(buf_read, ret,
+                                        buf_write + read_early_data_size, ret);
+                    read_early_data_size += ret;
+
+                    TEST_EQUAL(server_ep.ssl.total_early_data_size,
+                               written_early_data_size);
+                }
+                break;
+
+            case TEST_EARLY_DATA_SERVER_REJECTS: /* Intentional fallthrough */
+            case TEST_EARLY_DATA_HRR:
+                ret = mbedtls_ssl_handshake(&(server_ep.ssl));
+                /*
+                 * In this write loop we try to always stay below the
+                 * max_early_data_size limit but if max_early_data_size is very
+                 * small we may exceed the max_early_data_size limit on the
+                 * first write. In TEST_EARLY_DATA_SERVER_REJECTS/
+                 * TEST_EARLY_DATA_HRR scenario, this is for sure the case if
+                 * max_early_data_size is smaller than the smallest possible
+                 * inner content/protected record. Take into account this
+                 * possibility here but only for max_early_data_size values
+                 * that are close to write_size. Below, '1' is for the inner
+                 * type byte and '16' is to take into account some AEAD
+                 * expansion (tag, ...).
+                 */
+                if (ret == MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE) {
+                    if (scenario == TEST_EARLY_DATA_SERVER_REJECTS) {
+                        TEST_LE_U(max_early_data_size,
+                                  write_size + 1 +
+                                  MBEDTLS_SSL_CID_TLS1_3_PADDING_GRANULARITY);
+                    } else {
+                        TEST_LE_U(max_early_data_size,
+                                  write_size + 1 + 16 +
+                                  MBEDTLS_SSL_CID_TLS1_3_PADDING_GRANULARITY);
+                    }
+                    goto exit;
+                }
+
+                TEST_ASSERT(ret == MBEDTLS_ERR_SSL_WANT_READ);
+
+                TEST_EQUAL(server_pattern.counter, 1);
+                server_pattern.counter = 0;
+                if (expanded_early_data_chunk_size == 0) {
+                    expanded_early_data_chunk_size = server_ep.ssl.total_early_data_size;
+                }
+                break;
+        }
+        TEST_LE_U(server_ep.ssl.total_early_data_size, max_early_data_size);
+    } while (1);
+
+    mbedtls_debug_set_threshold(3);
+    ret = write_early_data(&(client_ep.ssl), buf_write, write_size);
+    TEST_EQUAL(ret, write_size);
+
+    ret = mbedtls_snprintf(pattern, sizeof(pattern),
+                           "EarlyData: Too much early data received");
+    TEST_ASSERT(ret < (int) sizeof(pattern));
+
+    ret = mbedtls_ssl_handshake(&(server_ep.ssl));
+    TEST_EQUAL(ret, MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE);
+    TEST_EQUAL(server_pattern.counter, 1);
+
+exit:
+    mbedtls_test_ssl_endpoint_free(&client_ep, NULL);
+    mbedtls_test_ssl_endpoint_free(&server_ep, NULL);
+    mbedtls_test_free_handshake_options(&client_options);
+    mbedtls_test_free_handshake_options(&server_options);
+    mbedtls_ssl_session_free(&saved_session);
+    mbedtls_free(buf_write);
+    mbedtls_free(buf_read);
+    mbedtls_debug_set_threshold(0);
+    PSA_DONE();
+}
+/* END_CASE */