Import mbedtls-2.27.0
Imports Mbed TLS 2.27.0 from https://github.com/ARMmbed/mbedtls.git
commit f71e28780841 ("Merge pull request #843 from
paul-elliott-arm/mbedtls-2.27.0rc0-pr") (tag mbedtls-2.27.0, v2.27.0).
Files that are not needed are removed.
cd lib/libmbedtls
rm -rf mbedtls
cp -R path/to/mbedtls-2.27.0/mbedtls .
cd mbedtls
rm CMakeLists.txt DartConfiguration.tcl Makefile
rm .gitignore .travis.yml .pylintrc .globalrc .mypy.ini BRANCHES.md
rm include/.gitignore include/CMakeLists.txt library/.gitignore
rm library/CMakeLists.txt library/Makefile
rm -rf .git .github doxygen configs programs scripts tests visualc yotta
rm -rf 3rdparty ChangeLog.d docs
rm -rf include/mbedtls/config_psa.h include/psa
rm library/psa_* library/mps_*
cd ..
git add mbedtls
This is a complete overwrite of previous code so earlier changes in the
previous branch import/mbedtls-2.22.0 will be added on top of this commit.
Signed-off-by: Jerome Forissier <jerome@forissier.org>
diff --git a/lib/libmbedtls/mbedtls/library/ecp.c b/lib/libmbedtls/mbedtls/library/ecp.c
index ff86b0f..ca49f99 100644
--- a/lib/libmbedtls/mbedtls/library/ecp.c
+++ b/lib/libmbedtls/mbedtls/library/ecp.c
@@ -1,8 +1,8 @@
-// SPDX-License-Identifier: Apache-2.0
/*
* Elliptic curves over GF(p): generic functions
*
- * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
+ * Copyright The Mbed TLS Contributors
+ * SPDX-License-Identifier: Apache-2.0
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may
* not use this file except in compliance with the License.
@@ -15,8 +15,6 @@
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
- *
- * This file is part of mbed TLS (https://tls.mbed.org)
*/
/*
@@ -41,11 +39,7 @@
* <http://eprint.iacr.org/2004/342.pdf>
*/
-#if !defined(MBEDTLS_CONFIG_FILE)
-#include "mbedtls/config.h"
-#else
-#include MBEDTLS_CONFIG_FILE
-#endif
+#include "common.h"
/**
* \brief Function level alternative implementation.
@@ -82,6 +76,9 @@
#include "mbedtls/threading.h"
#include "mbedtls/platform_util.h"
#include "mbedtls/error.h"
+#include "mbedtls/bn_mul.h"
+
+#include "ecp_invasive.h"
#include <string.h>
@@ -105,6 +102,16 @@
#include "mbedtls/ecp_internal.h"
+#if !defined(MBEDTLS_ECP_NO_INTERNAL_RNG)
+#if defined(MBEDTLS_HMAC_DRBG_C)
+#include "mbedtls/hmac_drbg.h"
+#elif defined(MBEDTLS_CTR_DRBG_C)
+#include "mbedtls/ctr_drbg.h"
+#else
+#error "Invalid configuration detected. Include check_config.h to ensure that the configuration is valid."
+#endif
+#endif /* MBEDTLS_ECP_NO_INTERNAL_RNG */
+
#if ( defined(__ARMCC_VERSION) || defined(_MSC_VER) ) && \
!defined(inline) && !defined(__cplusplus)
#define inline __inline
@@ -118,6 +125,144 @@
static unsigned long add_count, dbl_count, mul_count;
#endif
+#if !defined(MBEDTLS_ECP_NO_INTERNAL_RNG)
+/*
+ * Currently ecp_mul() takes a RNG function as an argument, used for
+ * side-channel protection, but it can be NULL. The initial reasoning was
+ * that people will pass non-NULL RNG when they care about side-channels, but
+ * unfortunately we have some APIs that call ecp_mul() with a NULL RNG, with
+ * no opportunity for the user to do anything about it.
+ *
+ * The obvious strategies for addressing that include:
+ * - change those APIs so that they take RNG arguments;
+ * - require a global RNG to be available to all crypto modules.
+ *
+ * Unfortunately those would break compatibility. So what we do instead is
+ * have our own internal DRBG instance, seeded from the secret scalar.
+ *
+ * The following is a light-weight abstraction layer for doing that with
+ * HMAC_DRBG (first choice) or CTR_DRBG.
+ */
+
+#if defined(MBEDTLS_HMAC_DRBG_C)
+
+/* DRBG context type */
+typedef mbedtls_hmac_drbg_context ecp_drbg_context;
+
+/* DRBG context init */
+static inline void ecp_drbg_init( ecp_drbg_context *ctx )
+{
+ mbedtls_hmac_drbg_init( ctx );
+}
+
+/* DRBG context free */
+static inline void ecp_drbg_free( ecp_drbg_context *ctx )
+{
+ mbedtls_hmac_drbg_free( ctx );
+}
+
+/* DRBG function */
+static inline int ecp_drbg_random( void *p_rng,
+ unsigned char *output, size_t output_len )
+{
+ return( mbedtls_hmac_drbg_random( p_rng, output, output_len ) );
+}
+
+/* DRBG context seeding */
+static int ecp_drbg_seed( ecp_drbg_context *ctx,
+ const mbedtls_mpi *secret, size_t secret_len )
+{
+ int ret;
+ unsigned char secret_bytes[MBEDTLS_ECP_MAX_BYTES];
+ /* The list starts with strong hashes */
+ const mbedtls_md_type_t md_type = mbedtls_md_list()[0];
+ const mbedtls_md_info_t *md_info = mbedtls_md_info_from_type( md_type );
+
+ if( secret_len > MBEDTLS_ECP_MAX_BYTES )
+ {
+ ret = MBEDTLS_ERR_ECP_RANDOM_FAILED;
+ goto cleanup;
+ }
+
+ MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( secret,
+ secret_bytes, secret_len ) );
+
+ ret = mbedtls_hmac_drbg_seed_buf( ctx, md_info, secret_bytes, secret_len );
+
+cleanup:
+ mbedtls_platform_zeroize( secret_bytes, secret_len );
+
+ return( ret );
+}
+
+#elif defined(MBEDTLS_CTR_DRBG_C)
+
+/* DRBG context type */
+typedef mbedtls_ctr_drbg_context ecp_drbg_context;
+
+/* DRBG context init */
+static inline void ecp_drbg_init( ecp_drbg_context *ctx )
+{
+ mbedtls_ctr_drbg_init( ctx );
+}
+
+/* DRBG context free */
+static inline void ecp_drbg_free( ecp_drbg_context *ctx )
+{
+ mbedtls_ctr_drbg_free( ctx );
+}
+
+/* DRBG function */
+static inline int ecp_drbg_random( void *p_rng,
+ unsigned char *output, size_t output_len )
+{
+ return( mbedtls_ctr_drbg_random( p_rng, output, output_len ) );
+}
+
+/*
+ * Since CTR_DRBG doesn't have a seed_buf() function the way HMAC_DRBG does,
+ * we need to pass an entropy function when seeding. So we use a dummy
+ * function for that, and pass the actual entropy as customisation string.
+ * (During seeding of CTR_DRBG the entropy input and customisation string are
+ * concatenated before being used to update the secret state.)
+ */
+static int ecp_ctr_drbg_null_entropy(void *ctx, unsigned char *out, size_t len)
+{
+ (void) ctx;
+ memset( out, 0, len );
+ return( 0 );
+}
+
+/* DRBG context seeding */
+static int ecp_drbg_seed( ecp_drbg_context *ctx,
+ const mbedtls_mpi *secret, size_t secret_len )
+{
+ int ret;
+ unsigned char secret_bytes[MBEDTLS_ECP_MAX_BYTES];
+
+ if( secret_len > MBEDTLS_ECP_MAX_BYTES )
+ {
+ ret = MBEDTLS_ERR_ECP_RANDOM_FAILED;
+ goto cleanup;
+ }
+
+ MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( secret,
+ secret_bytes, secret_len ) );
+
+ ret = mbedtls_ctr_drbg_seed( ctx, ecp_ctr_drbg_null_entropy, NULL,
+ secret_bytes, secret_len );
+
+cleanup:
+ mbedtls_platform_zeroize( secret_bytes, secret_len );
+
+ return( ret );
+}
+
+#else
+#error "Invalid configuration detected. Include check_config.h to ensure that the configuration is valid."
+#endif /* DRBG modules */
+#endif /* MBEDTLS_ECP_NO_INTERNAL_RNG */
+
#if defined(MBEDTLS_ECP_RESTARTABLE)
/*
* Maximum number of "basic operations" to be done in a row.
@@ -165,6 +310,10 @@
ecp_rsm_comb_core, /* ecp_mul_comb_core() */
ecp_rsm_final_norm, /* do the final normalization */
} state;
+#if !defined(MBEDTLS_ECP_NO_INTERNAL_RNG)
+ ecp_drbg_context drbg_ctx;
+ unsigned char drbg_seeded;
+#endif
};
/*
@@ -177,6 +326,10 @@
ctx->T = NULL;
ctx->T_size = 0;
ctx->state = ecp_rsm_init;
+#if !defined(MBEDTLS_ECP_NO_INTERNAL_RNG)
+ ecp_drbg_init( &ctx->drbg_ctx );
+ ctx->drbg_seeded = 0;
+#endif
}
/*
@@ -198,6 +351,10 @@
mbedtls_free( ctx->T );
}
+#if !defined(MBEDTLS_ECP_NO_INTERNAL_RNG)
+ ecp_drbg_free( &ctx->drbg_ctx );
+#endif
+
ecp_restart_rsm_init( ctx );
}
@@ -345,26 +502,6 @@
#endif /* MBEDTLS_ECP_RESTARTABLE */
-#if defined(MBEDTLS_ECP_DP_SECP192R1_ENABLED) || \
- defined(MBEDTLS_ECP_DP_SECP224R1_ENABLED) || \
- defined(MBEDTLS_ECP_DP_SECP256R1_ENABLED) || \
- defined(MBEDTLS_ECP_DP_SECP384R1_ENABLED) || \
- defined(MBEDTLS_ECP_DP_SECP521R1_ENABLED) || \
- defined(MBEDTLS_ECP_DP_BP256R1_ENABLED) || \
- defined(MBEDTLS_ECP_DP_BP384R1_ENABLED) || \
- defined(MBEDTLS_ECP_DP_BP512R1_ENABLED) || \
- defined(MBEDTLS_ECP_DP_SECP192K1_ENABLED) || \
- defined(MBEDTLS_ECP_DP_SECP224K1_ENABLED) || \
- defined(MBEDTLS_ECP_DP_SECP256K1_ENABLED) || \
- defined(MBEDTLS_ECP_DP_SM2_ENABLED)
-#define ECP_SHORTWEIERSTRASS
-#endif
-
-#if defined(MBEDTLS_ECP_DP_CURVE25519_ENABLED) || \
- defined(MBEDTLS_ECP_DP_CURVE448_ENABLED)
-#define ECP_MONTGOMERY
-#endif
-
/*
* List of supported curves:
* - internal ID
@@ -412,12 +549,11 @@
#if defined(MBEDTLS_ECP_DP_SECP192K1_ENABLED)
{ MBEDTLS_ECP_DP_SECP192K1, 18, 192, "secp192k1" },
#endif
-#if defined(MBEDTLS_ECP_DP_CURVE25519_ENABLED) && defined(MBEDTLS_ECDH_VARIANT_EVEREST_ENABLED)
+#if defined(MBEDTLS_ECP_DP_CURVE25519_ENABLED)
{ MBEDTLS_ECP_DP_CURVE25519, 29, 256, "x25519" },
#endif
-#if defined(MBEDTLS_ECP_DP_SM2_ENABLED)
- /* https://tools.ietf.org/id/draft-yang-tls-tls13-sm-suites-05.html */
- { MBEDTLS_ECP_DP_SM2, 41, 256, "sm2" },
+#if defined(MBEDTLS_ECP_DP_CURVE448_ENABLED)
+ { MBEDTLS_ECP_DP_CURVE448, 30, 448, "x448" },
#endif
{ MBEDTLS_ECP_DP_NONE, 0, 0, NULL },
};
@@ -746,7 +882,8 @@
plen = mbedtls_mpi_size( &grp->P );
-#if defined(ECP_MONTGOMERY)
+#if defined(MBEDTLS_ECP_MONTGOMERY_ENABLED)
+ (void) format; /* Montgomery curves always use the same point format */
if( mbedtls_ecp_get_type( grp ) == MBEDTLS_ECP_TYPE_MONTGOMERY )
{
*olen = plen;
@@ -756,7 +893,7 @@
MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary_le( &P->X, buf, plen ) );
}
#endif
-#if defined(ECP_SHORTWEIERSTRASS)
+#if defined(MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED)
if( mbedtls_ecp_get_type( grp ) == MBEDTLS_ECP_TYPE_SHORT_WEIERSTRASS )
{
/*
@@ -819,7 +956,7 @@
plen = mbedtls_mpi_size( &grp->P );
-#if defined(ECP_MONTGOMERY)
+#if defined(MBEDTLS_ECP_MONTGOMERY_ENABLED)
if( mbedtls_ecp_get_type( grp ) == MBEDTLS_ECP_TYPE_MONTGOMERY )
{
if( plen != ilen )
@@ -835,7 +972,7 @@
MBEDTLS_MPI_CHK( mbedtls_mpi_lset( &pt->Z, 1 ) );
}
#endif
-#if defined(ECP_SHORTWEIERSTRASS)
+#if defined(MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED)
if( mbedtls_ecp_get_type( grp ) == MBEDTLS_ECP_TYPE_SHORT_WEIERSTRASS )
{
if( buf[0] == 0x00 )
@@ -1109,6 +1246,13 @@
while( (N).s < 0 && mbedtls_mpi_cmp_int( &(N), 0 ) != 0 ) \
MBEDTLS_MPI_CHK( mbedtls_mpi_add_mpi( &(N), &(N), &grp->P ) )
+#if ( defined(MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED) && \
+ !( defined(MBEDTLS_ECP_NO_FALLBACK) && \
+ defined(MBEDTLS_ECP_DOUBLE_JAC_ALT) && \
+ defined(MBEDTLS_ECP_ADD_MIXED_ALT) ) ) || \
+ ( defined(MBEDTLS_ECP_MONTGOMERY_ENABLED) && \
+ !( defined(MBEDTLS_ECP_NO_FALLBACK) && \
+ defined(MBEDTLS_ECP_DOUBLE_ADD_MXZ_ALT) ) )
static inline int mbedtls_mpi_sub_mod( const mbedtls_ecp_group *grp,
mbedtls_mpi *X,
const mbedtls_mpi *A,
@@ -1120,6 +1264,7 @@
cleanup:
return( ret );
}
+#endif /* All functions referencing mbedtls_mpi_sub_mod() are alt-implemented without fallback */
/*
* Reduce a mbedtls_mpi mod p in-place, to use after mbedtls_mpi_add_mpi and mbedtls_mpi_mul_int.
@@ -1142,6 +1287,10 @@
return( ret );
}
+#if defined(MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED) && \
+ !( defined(MBEDTLS_ECP_NO_FALLBACK) && \
+ defined(MBEDTLS_ECP_DOUBLE_JAC_ALT) && \
+ defined(MBEDTLS_ECP_ADD_MIXED_ALT) )
static inline int mbedtls_mpi_shift_l_mod( const mbedtls_ecp_group *grp,
mbedtls_mpi *X,
size_t count )
@@ -1152,8 +1301,9 @@
cleanup:
return( ret );
}
+#endif /* All functions referencing mbedtls_mpi_shift_l_mod() are alt-implemented without fallback */
-#if defined(ECP_SHORTWEIERSTRASS)
+#if defined(MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED)
/*
* For curves in short Weierstrass form, we do all the internal operations in
* Jacobian coordinates.
@@ -1168,9 +1318,6 @@
*/
static int ecp_normalize_jac( const mbedtls_ecp_group *grp, mbedtls_ecp_point *pt )
{
- int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
- mbedtls_mpi Zi, ZZi;
-
if( mbedtls_mpi_cmp_int( &pt->Z, 0 ) == 0 )
return( 0 );
@@ -1179,6 +1326,11 @@
return( mbedtls_internal_ecp_normalize_jac( grp, pt ) );
#endif /* MBEDTLS_ECP_NORMALIZE_JAC_ALT */
+#if defined(MBEDTLS_ECP_NO_FALLBACK) && defined(MBEDTLS_ECP_NORMALIZE_JAC_ALT)
+ return( MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE );
+#else
+ int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+ mbedtls_mpi Zi, ZZi;
mbedtls_mpi_init( &Zi ); mbedtls_mpi_init( &ZZi );
/*
@@ -1204,6 +1356,7 @@
mbedtls_mpi_free( &Zi ); mbedtls_mpi_free( &ZZi );
return( ret );
+#endif /* !defined(MBEDTLS_ECP_NO_FALLBACK) || !defined(MBEDTLS_ECP_NORMALIZE_JAC_ALT) */
}
/*
@@ -1220,10 +1373,6 @@
static int ecp_normalize_jac_many( const mbedtls_ecp_group *grp,
mbedtls_ecp_point *T[], size_t T_size )
{
- int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
- size_t i;
- mbedtls_mpi *c, u, Zi, ZZi;
-
if( T_size < 2 )
return( ecp_normalize_jac( grp, *T ) );
@@ -1232,6 +1381,13 @@
return( mbedtls_internal_ecp_normalize_jac_many( grp, T, T_size ) );
#endif
+#if defined(MBEDTLS_ECP_NO_FALLBACK) && defined(MBEDTLS_ECP_NORMALIZE_JAC_MANY_ALT)
+ return( MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE );
+#else
+ int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+ size_t i;
+ mbedtls_mpi *c, u, Zi, ZZi;
+
if( ( c = mbedtls_calloc( T_size, sizeof( mbedtls_mpi ) ) ) == NULL )
return( MBEDTLS_ERR_ECP_ALLOC_FAILED );
@@ -1299,6 +1455,7 @@
mbedtls_free( c );
return( ret );
+#endif /* !defined(MBEDTLS_ECP_NO_FALLBACK) || !defined(MBEDTLS_ECP_NORMALIZE_JAC_MANY_ALT) */
}
/*
@@ -1343,9 +1500,6 @@
static int ecp_double_jac( const mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
const mbedtls_ecp_point *P )
{
- int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
- mbedtls_mpi M, S, T, U;
-
#if defined(MBEDTLS_SELF_TEST)
dbl_count++;
#endif
@@ -1355,6 +1509,12 @@
return( mbedtls_internal_ecp_double_jac( grp, R, P ) );
#endif /* MBEDTLS_ECP_DOUBLE_JAC_ALT */
+#if defined(MBEDTLS_ECP_NO_FALLBACK) && defined(MBEDTLS_ECP_DOUBLE_JAC_ALT)
+ return( MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE );
+#else
+ int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+ mbedtls_mpi M, S, T, U;
+
mbedtls_mpi_init( &M ); mbedtls_mpi_init( &S ); mbedtls_mpi_init( &T ); mbedtls_mpi_init( &U );
/* Special case for A = -3 */
@@ -1416,6 +1576,7 @@
mbedtls_mpi_free( &M ); mbedtls_mpi_free( &S ); mbedtls_mpi_free( &T ); mbedtls_mpi_free( &U );
return( ret );
+#endif /* !defined(MBEDTLS_ECP_NO_FALLBACK) || !defined(MBEDTLS_ECP_DOUBLE_JAC_ALT) */
}
/*
@@ -1439,9 +1600,6 @@
static int ecp_add_mixed( const mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
const mbedtls_ecp_point *P, const mbedtls_ecp_point *Q )
{
- int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
- mbedtls_mpi T1, T2, T3, T4, X, Y, Z;
-
#if defined(MBEDTLS_SELF_TEST)
add_count++;
#endif
@@ -1451,6 +1609,12 @@
return( mbedtls_internal_ecp_add_mixed( grp, R, P, Q ) );
#endif /* MBEDTLS_ECP_ADD_MIXED_ALT */
+#if defined(MBEDTLS_ECP_NO_FALLBACK) && defined(MBEDTLS_ECP_ADD_MIXED_ALT)
+ return( MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE );
+#else
+ int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+ mbedtls_mpi T1, T2, T3, T4, X, Y, Z;
+
/*
* Trivial cases: P == 0 or Q == 0 (case 1)
*/
@@ -1515,6 +1679,7 @@
mbedtls_mpi_free( &X ); mbedtls_mpi_free( &Y ); mbedtls_mpi_free( &Z );
return( ret );
+#endif /* !defined(MBEDTLS_ECP_NO_FALLBACK) || !defined(MBEDTLS_ECP_ADD_MIXED_ALT) */
}
/*
@@ -1527,31 +1692,21 @@
static int ecp_randomize_jac( const mbedtls_ecp_group *grp, mbedtls_ecp_point *pt,
int (*f_rng)(void *, unsigned char *, size_t), void *p_rng )
{
- int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
- mbedtls_mpi l, ll;
- size_t p_size;
- int count = 0;
-
#if defined(MBEDTLS_ECP_RANDOMIZE_JAC_ALT)
if( mbedtls_internal_ecp_grp_capable( grp ) )
return( mbedtls_internal_ecp_randomize_jac( grp, pt, f_rng, p_rng ) );
#endif /* MBEDTLS_ECP_RANDOMIZE_JAC_ALT */
- p_size = ( grp->pbits + 7 ) / 8;
+#if defined(MBEDTLS_ECP_NO_FALLBACK) && defined(MBEDTLS_ECP_RANDOMIZE_JAC_ALT)
+ return( MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE );
+#else
+ int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+ mbedtls_mpi l, ll;
+
mbedtls_mpi_init( &l ); mbedtls_mpi_init( &ll );
/* Generate l such that 1 < l < p */
- do
- {
- MBEDTLS_MPI_CHK( mbedtls_mpi_fill_random( &l, p_size, f_rng, p_rng ) );
-
- while( mbedtls_mpi_cmp_mpi( &l, &grp->P ) >= 0 )
- MBEDTLS_MPI_CHK( mbedtls_mpi_shift_r( &l, 1 ) );
-
- if( count++ > 10 )
- return( MBEDTLS_ERR_ECP_RANDOM_FAILED );
- }
- while( mbedtls_mpi_cmp_int( &l, 1 ) <= 0 );
+ MBEDTLS_MPI_CHK( mbedtls_mpi_random( &l, 2, &grp->P, f_rng, p_rng ) );
/* Z = l * Z */
MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mod( grp, &pt->Z, &pt->Z, &l ) );
@@ -1567,7 +1722,10 @@
cleanup:
mbedtls_mpi_free( &l ); mbedtls_mpi_free( &ll );
+ if( ret == MBEDTLS_ERR_MPI_NOT_ACCEPTABLE )
+ ret = MBEDTLS_ERR_ECP_RANDOM_FAILED;
return( ret );
+#endif /* !defined(MBEDTLS_ECP_NO_FALLBACK) || !defined(MBEDTLS_ECP_RANDOMIZE_JAC_ALT) */
}
/*
@@ -1899,7 +2057,9 @@
i = d;
MBEDTLS_MPI_CHK( ecp_select_comb( grp, R, T, T_size, x[i] ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_lset( &R->Z, 1 ) );
+#if defined(MBEDTLS_ECP_NO_INTERNAL_RNG)
if( f_rng != 0 )
+#endif
MBEDTLS_MPI_CHK( ecp_randomize_jac( grp, R, f_rng, p_rng ) );
}
@@ -2020,6 +2180,7 @@
rs_ctx->rsm->state = ecp_rsm_final_norm;
final_norm:
+ MBEDTLS_ECP_BUDGET( MBEDTLS_ECP_OPS_INV );
#endif
/*
* Knowledge of the jacobian coordinates may leak the last few bits of the
@@ -2032,10 +2193,11 @@
*
* Avoid the leak by randomizing coordinates before we normalize them.
*/
+#if defined(MBEDTLS_ECP_NO_INTERNAL_RNG)
if( f_rng != 0 )
+#endif
MBEDTLS_MPI_CHK( ecp_randomize_jac( grp, RR, f_rng, p_rng ) );
- MBEDTLS_ECP_BUDGET( MBEDTLS_ECP_OPS_INV );
MBEDTLS_MPI_CHK( ecp_normalize_jac( grp, RR ) );
#if defined(MBEDTLS_ECP_RESTARTABLE)
@@ -2106,11 +2268,44 @@
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
unsigned char w, p_eq_g, i;
size_t d;
- unsigned char T_size, T_ok;
- mbedtls_ecp_point *T;
+ unsigned char T_size = 0, T_ok = 0;
+ mbedtls_ecp_point *T = NULL;
+#if !defined(MBEDTLS_ECP_NO_INTERNAL_RNG)
+ ecp_drbg_context drbg_ctx;
+
+ ecp_drbg_init( &drbg_ctx );
+#endif
ECP_RS_ENTER( rsm );
+#if !defined(MBEDTLS_ECP_NO_INTERNAL_RNG)
+ if( f_rng == NULL )
+ {
+ /* Adjust pointers */
+ f_rng = &ecp_drbg_random;
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+ if( rs_ctx != NULL && rs_ctx->rsm != NULL )
+ p_rng = &rs_ctx->rsm->drbg_ctx;
+ else
+#endif
+ p_rng = &drbg_ctx;
+
+ /* Initialize internal DRBG if necessary */
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+ if( rs_ctx == NULL || rs_ctx->rsm == NULL ||
+ rs_ctx->rsm->drbg_seeded == 0 )
+#endif
+ {
+ const size_t m_len = ( grp->nbits + 7 ) / 8;
+ MBEDTLS_MPI_CHK( ecp_drbg_seed( p_rng, m, m_len ) );
+ }
+#if defined(MBEDTLS_ECP_RESTARTABLE)
+ if( rs_ctx != NULL && rs_ctx->rsm != NULL )
+ rs_ctx->rsm->drbg_seeded = 1;
+#endif
+ }
+#endif /* !MBEDTLS_ECP_NO_INTERNAL_RNG */
+
/* Is P the base point ? */
#if MBEDTLS_ECP_FIXED_POINT_OPTIM == 1
p_eq_g = ( mbedtls_mpi_cmp_mpi( &P->Y, &grp->G.Y ) == 0 &&
@@ -2182,6 +2377,10 @@
cleanup:
+#if !defined(MBEDTLS_ECP_NO_INTERNAL_RNG)
+ ecp_drbg_free( &drbg_ctx );
+#endif
+
/* does T belong to the group? */
if( T == grp->T )
T = NULL;
@@ -2218,9 +2417,9 @@
return( ret );
}
-#endif /* ECP_SHORTWEIERSTRASS */
+#endif /* MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED */
-#if defined(ECP_MONTGOMERY)
+#if defined(MBEDTLS_ECP_MONTGOMERY_ENABLED)
/*
* For Montgomery curves, we do all the internal arithmetic in projective
* coordinates. Import/export of points uses only the x coordinates, which is
@@ -2235,19 +2434,22 @@
*/
static int ecp_normalize_mxz( const mbedtls_ecp_group *grp, mbedtls_ecp_point *P )
{
- int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
-
#if defined(MBEDTLS_ECP_NORMALIZE_MXZ_ALT)
if( mbedtls_internal_ecp_grp_capable( grp ) )
return( mbedtls_internal_ecp_normalize_mxz( grp, P ) );
#endif /* MBEDTLS_ECP_NORMALIZE_MXZ_ALT */
+#if defined(MBEDTLS_ECP_NO_FALLBACK) && defined(MBEDTLS_ECP_NORMALIZE_MXZ_ALT)
+ return( MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE );
+#else
+ int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
MBEDTLS_MPI_CHK( mbedtls_mpi_inv_mod( &P->Z, &P->Z, &grp->P ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mod( grp, &P->X, &P->X, &P->Z ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_lset( &P->Z, 1 ) );
cleanup:
return( ret );
+#endif /* !defined(MBEDTLS_ECP_NO_FALLBACK) || !defined(MBEDTLS_ECP_NORMALIZE_MXZ_ALT) */
}
/*
@@ -2261,31 +2463,20 @@
static int ecp_randomize_mxz( const mbedtls_ecp_group *grp, mbedtls_ecp_point *P,
int (*f_rng)(void *, unsigned char *, size_t), void *p_rng )
{
- int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
- mbedtls_mpi l;
- size_t p_size;
- int count = 0;
-
#if defined(MBEDTLS_ECP_RANDOMIZE_MXZ_ALT)
if( mbedtls_internal_ecp_grp_capable( grp ) )
- return( mbedtls_internal_ecp_randomize_mxz( grp, P, f_rng, p_rng );
+ return( mbedtls_internal_ecp_randomize_mxz( grp, P, f_rng, p_rng ) );
#endif /* MBEDTLS_ECP_RANDOMIZE_MXZ_ALT */
- p_size = ( grp->pbits + 7 ) / 8;
+#if defined(MBEDTLS_ECP_NO_FALLBACK) && defined(MBEDTLS_ECP_RANDOMIZE_MXZ_ALT)
+ return( MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE );
+#else
+ int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+ mbedtls_mpi l;
mbedtls_mpi_init( &l );
/* Generate l such that 1 < l < p */
- do
- {
- MBEDTLS_MPI_CHK( mbedtls_mpi_fill_random( &l, p_size, f_rng, p_rng ) );
-
- while( mbedtls_mpi_cmp_mpi( &l, &grp->P ) >= 0 )
- MBEDTLS_MPI_CHK( mbedtls_mpi_shift_r( &l, 1 ) );
-
- if( count++ > 10 )
- return( MBEDTLS_ERR_ECP_RANDOM_FAILED );
- }
- while( mbedtls_mpi_cmp_int( &l, 1 ) <= 0 );
+ MBEDTLS_MPI_CHK( mbedtls_mpi_random( &l, 2, &grp->P, f_rng, p_rng ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mod( grp, &P->X, &P->X, &l ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mod( grp, &P->Z, &P->Z, &l ) );
@@ -2293,7 +2484,10 @@
cleanup:
mbedtls_mpi_free( &l );
+ if( ret == MBEDTLS_ERR_MPI_NOT_ACCEPTABLE )
+ ret = MBEDTLS_ERR_ECP_RANDOM_FAILED;
return( ret );
+#endif /* !defined(MBEDTLS_ECP_NO_FALLBACK) || !defined(MBEDTLS_ECP_RANDOMIZE_MXZ_ALT) */
}
/*
@@ -2316,14 +2510,17 @@
const mbedtls_ecp_point *P, const mbedtls_ecp_point *Q,
const mbedtls_mpi *d )
{
- int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
- mbedtls_mpi A, AA, B, BB, E, C, D, DA, CB;
-
#if defined(MBEDTLS_ECP_DOUBLE_ADD_MXZ_ALT)
if( mbedtls_internal_ecp_grp_capable( grp ) )
return( mbedtls_internal_ecp_double_add_mxz( grp, R, S, P, Q, d ) );
#endif /* MBEDTLS_ECP_DOUBLE_ADD_MXZ_ALT */
+#if defined(MBEDTLS_ECP_NO_FALLBACK) && defined(MBEDTLS_ECP_DOUBLE_ADD_MXZ_ALT)
+ return( MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE );
+#else
+ int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+ mbedtls_mpi A, AA, B, BB, E, C, D, DA, CB;
+
mbedtls_mpi_init( &A ); mbedtls_mpi_init( &AA ); mbedtls_mpi_init( &B );
mbedtls_mpi_init( &BB ); mbedtls_mpi_init( &E ); mbedtls_mpi_init( &C );
mbedtls_mpi_init( &D ); mbedtls_mpi_init( &DA ); mbedtls_mpi_init( &CB );
@@ -2337,7 +2534,7 @@
MBEDTLS_MPI_CHK( mbedtls_mpi_sub_mod( grp, &D, &Q->X, &Q->Z ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mod( grp, &DA, &D, &A ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mod( grp, &CB, &C, &B ) );
- MBEDTLS_MPI_CHK( mbedtls_mpi_add_mpi( &S->X, &DA, &CB ) ); MOD_MUL( S->X );
+ MBEDTLS_MPI_CHK( mbedtls_mpi_add_mod( grp, &S->X, &DA, &CB ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mod( grp, &S->X, &S->X, &S->X ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_sub_mod( grp, &S->Z, &DA, &CB ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mod( grp, &S->Z, &S->Z, &S->Z ) );
@@ -2353,6 +2550,7 @@
mbedtls_mpi_free( &D ); mbedtls_mpi_free( &DA ); mbedtls_mpi_free( &CB );
return( ret );
+#endif /* !defined(MBEDTLS_ECP_NO_FALLBACK) || !defined(MBEDTLS_ECP_DOUBLE_ADD_MXZ_ALT) */
}
/*
@@ -2369,9 +2567,23 @@
unsigned char b;
mbedtls_ecp_point RP;
mbedtls_mpi PX;
+#if !defined(MBEDTLS_ECP_NO_INTERNAL_RNG)
+ ecp_drbg_context drbg_ctx;
+ ecp_drbg_init( &drbg_ctx );
+#endif
mbedtls_ecp_point_init( &RP ); mbedtls_mpi_init( &PX );
+#if !defined(MBEDTLS_ECP_NO_INTERNAL_RNG)
+ if( f_rng == NULL )
+ {
+ const size_t m_len = ( grp->nbits + 7 ) / 8;
+ MBEDTLS_MPI_CHK( ecp_drbg_seed( &drbg_ctx, m, m_len ) );
+ f_rng = &ecp_drbg_random;
+ p_rng = &drbg_ctx;
+ }
+#endif /* !MBEDTLS_ECP_NO_INTERNAL_RNG */
+
/* Save PX and read from P before writing to R, in case P == R */
MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &PX, &P->X ) );
MBEDTLS_MPI_CHK( mbedtls_ecp_copy( &RP, P ) );
@@ -2385,7 +2597,9 @@
MOD_ADD( RP.X );
/* Randomize coordinates of the starting point */
+#if defined(MBEDTLS_ECP_NO_INTERNAL_RNG)
if( f_rng != NULL )
+#endif
MBEDTLS_MPI_CHK( ecp_randomize_mxz( grp, &RP, f_rng, p_rng ) );
/* Loop invariant: R = result so far, RP = R + P */
@@ -2418,18 +2632,24 @@
*
* Avoid the leak by randomizing coordinates before we normalize them.
*/
+#if defined(MBEDTLS_ECP_NO_INTERNAL_RNG)
if( f_rng != NULL )
+#endif
MBEDTLS_MPI_CHK( ecp_randomize_mxz( grp, R, f_rng, p_rng ) );
MBEDTLS_MPI_CHK( ecp_normalize_mxz( grp, R ) );
cleanup:
+#if !defined(MBEDTLS_ECP_NO_INTERNAL_RNG)
+ ecp_drbg_free( &drbg_ctx );
+#endif
+
mbedtls_ecp_point_free( &RP ); mbedtls_mpi_free( &PX );
return( ret );
}
-#endif /* ECP_MONTGOMERY */
+#endif /* MBEDTLS_ECP_MONTGOMERY_ENABLED */
/*
* Restartable multiplication R = m * P
@@ -2452,6 +2672,8 @@
/* reset ops count for this call if top-level */
if( rs_ctx != NULL && rs_ctx->depth++ == 0 )
rs_ctx->ops_done = 0;
+#else
+ (void) rs_ctx;
#endif
#if defined(MBEDTLS_ECP_INTERNAL_ALT)
@@ -2473,11 +2695,11 @@
}
ret = MBEDTLS_ERR_ECP_BAD_INPUT_DATA;
-#if defined(ECP_MONTGOMERY)
+#if defined(MBEDTLS_ECP_MONTGOMERY_ENABLED)
if( mbedtls_ecp_get_type( grp ) == MBEDTLS_ECP_TYPE_MONTGOMERY )
MBEDTLS_MPI_CHK( ecp_mul_mxz( grp, R, m, P, f_rng, p_rng ) );
#endif
-#if defined(ECP_SHORTWEIERSTRASS)
+#if defined(MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED)
if( mbedtls_ecp_get_type( grp ) == MBEDTLS_ECP_TYPE_SHORT_WEIERSTRASS )
MBEDTLS_MPI_CHK( ecp_mul_comb( grp, R, m, P, f_rng, p_rng, rs_ctx ) );
#endif
@@ -2511,7 +2733,7 @@
return( mbedtls_ecp_mul_restartable( grp, R, m, P, f_rng, p_rng, NULL ) );
}
-#if defined(ECP_SHORTWEIERSTRASS)
+#if defined(MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED)
/*
* Check that an affine point is valid as a public key,
* short weierstrass curves (SEC1 3.2.3.1)
@@ -2559,10 +2781,11 @@
return( ret );
}
-#endif /* ECP_SHORTWEIERSTRASS */
+#endif /* MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED */
+#if defined(MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED)
/*
- * R = m * P with shortcuts for m == 1 and m == -1
+ * R = m * P with shortcuts for m == 0, m == 1 and m == -1
* NOT constant-time - ONLY for short Weierstrass!
*/
static int mbedtls_ecp_mul_shortcuts( mbedtls_ecp_group *grp,
@@ -2573,7 +2796,11 @@
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
- if( mbedtls_mpi_cmp_int( m, 1 ) == 0 )
+ if( mbedtls_mpi_cmp_int( m, 0 ) == 0 )
+ {
+ MBEDTLS_MPI_CHK( mbedtls_ecp_set_zero( R ) );
+ }
+ else if( mbedtls_mpi_cmp_int( m, 1 ) == 0 )
{
MBEDTLS_MPI_CHK( mbedtls_ecp_copy( R, P ) );
}
@@ -2706,8 +2933,100 @@
ECP_VALIDATE_RET( Q != NULL );
return( mbedtls_ecp_muladd_restartable( grp, R, m, P, n, Q, NULL ) );
}
+#endif /* MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED */
-#if defined(ECP_MONTGOMERY)
+#if defined(MBEDTLS_ECP_MONTGOMERY_ENABLED)
+#if defined(MBEDTLS_ECP_DP_CURVE25519_ENABLED)
+#define ECP_MPI_INIT(s, n, p) {s, (n), (mbedtls_mpi_uint *)(p)}
+#define ECP_MPI_INIT_ARRAY(x) \
+ ECP_MPI_INIT(1, sizeof(x) / sizeof(mbedtls_mpi_uint), x)
+/*
+ * Constants for the two points other than 0, 1, -1 (mod p) in
+ * https://cr.yp.to/ecdh.html#validate
+ * See ecp_check_pubkey_x25519().
+ */
+static const mbedtls_mpi_uint x25519_bad_point_1[] = {
+ MBEDTLS_BYTES_TO_T_UINT_8( 0xe0, 0xeb, 0x7a, 0x7c, 0x3b, 0x41, 0xb8, 0xae ),
+ MBEDTLS_BYTES_TO_T_UINT_8( 0x16, 0x56, 0xe3, 0xfa, 0xf1, 0x9f, 0xc4, 0x6a ),
+ MBEDTLS_BYTES_TO_T_UINT_8( 0xda, 0x09, 0x8d, 0xeb, 0x9c, 0x32, 0xb1, 0xfd ),
+ MBEDTLS_BYTES_TO_T_UINT_8( 0x86, 0x62, 0x05, 0x16, 0x5f, 0x49, 0xb8, 0x00 ),
+};
+static const mbedtls_mpi_uint x25519_bad_point_2[] = {
+ MBEDTLS_BYTES_TO_T_UINT_8( 0x5f, 0x9c, 0x95, 0xbc, 0xa3, 0x50, 0x8c, 0x24 ),
+ MBEDTLS_BYTES_TO_T_UINT_8( 0xb1, 0xd0, 0xb1, 0x55, 0x9c, 0x83, 0xef, 0x5b ),
+ MBEDTLS_BYTES_TO_T_UINT_8( 0x04, 0x44, 0x5c, 0xc4, 0x58, 0x1c, 0x8e, 0x86 ),
+ MBEDTLS_BYTES_TO_T_UINT_8( 0xd8, 0x22, 0x4e, 0xdd, 0xd0, 0x9f, 0x11, 0x57 ),
+};
+static const mbedtls_mpi ecp_x25519_bad_point_1 = ECP_MPI_INIT_ARRAY(
+ x25519_bad_point_1 );
+static const mbedtls_mpi ecp_x25519_bad_point_2 = ECP_MPI_INIT_ARRAY(
+ x25519_bad_point_2 );
+#endif /* MBEDTLS_ECP_DP_CURVE25519_ENABLED */
+
+/*
+ * Check that the input point is not one of the low-order points.
+ * This is recommended by the "May the Fourth" paper:
+ * https://eprint.iacr.org/2017/806.pdf
+ * Those points are never sent by an honest peer.
+ */
+static int ecp_check_bad_points_mx( const mbedtls_mpi *X, const mbedtls_mpi *P,
+ const mbedtls_ecp_group_id grp_id )
+{
+ int ret;
+ mbedtls_mpi XmP;
+
+ mbedtls_mpi_init( &XmP );
+
+ /* Reduce X mod P so that we only need to check values less than P.
+ * We know X < 2^256 so we can proceed by subtraction. */
+ MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &XmP, X ) );
+ while( mbedtls_mpi_cmp_mpi( &XmP, P ) >= 0 )
+ MBEDTLS_MPI_CHK( mbedtls_mpi_sub_mpi( &XmP, &XmP, P ) );
+
+ /* Check against the known bad values that are less than P. For Curve448
+ * these are 0, 1 and -1. For Curve25519 we check the values less than P
+ * from the following list: https://cr.yp.to/ecdh.html#validate */
+ if( mbedtls_mpi_cmp_int( &XmP, 1 ) <= 0 ) /* takes care of 0 and 1 */
+ {
+ ret = MBEDTLS_ERR_ECP_INVALID_KEY;
+ goto cleanup;
+ }
+
+#if defined(MBEDTLS_ECP_DP_CURVE25519_ENABLED)
+ if( grp_id == MBEDTLS_ECP_DP_CURVE25519 )
+ {
+ if( mbedtls_mpi_cmp_mpi( &XmP, &ecp_x25519_bad_point_1 ) == 0 )
+ {
+ ret = MBEDTLS_ERR_ECP_INVALID_KEY;
+ goto cleanup;
+ }
+
+ if( mbedtls_mpi_cmp_mpi( &XmP, &ecp_x25519_bad_point_2 ) == 0 )
+ {
+ ret = MBEDTLS_ERR_ECP_INVALID_KEY;
+ goto cleanup;
+ }
+ }
+#else
+ (void) grp_id;
+#endif
+
+ /* Final check: check if XmP + 1 is P (final because it changes XmP!) */
+ MBEDTLS_MPI_CHK( mbedtls_mpi_add_int( &XmP, &XmP, 1 ) );
+ if( mbedtls_mpi_cmp_mpi( &XmP, P ) == 0 )
+ {
+ ret = MBEDTLS_ERR_ECP_INVALID_KEY;
+ goto cleanup;
+ }
+
+ ret = 0;
+
+cleanup:
+ mbedtls_mpi_free( &XmP );
+
+ return( ret );
+}
+
/*
* Check validity of a public key for Montgomery curves with x-only schemes
*/
@@ -2719,9 +3038,15 @@
if( mbedtls_mpi_size( &pt->X ) > ( grp->nbits + 7 ) / 8 )
return( MBEDTLS_ERR_ECP_INVALID_KEY );
- return( 0 );
+ /* Implicit in all standards (as they don't consider negative numbers):
+ * X must be non-negative. This is normally ensured by the way it's
+ * encoded for transmission, but let's be extra sure. */
+ if( mbedtls_mpi_cmp_int( &pt->X, 0 ) < 0 )
+ return( MBEDTLS_ERR_ECP_INVALID_KEY );
+
+ return( ecp_check_bad_points_mx( &pt->X, &grp->P, grp->id ) );
}
-#endif /* ECP_MONTGOMERY */
+#endif /* MBEDTLS_ECP_MONTGOMERY_ENABLED */
/*
* Check that a point is valid as a public key
@@ -2736,11 +3061,11 @@
if( mbedtls_mpi_cmp_int( &pt->Z, 1 ) != 0 )
return( MBEDTLS_ERR_ECP_INVALID_KEY );
-#if defined(ECP_MONTGOMERY)
+#if defined(MBEDTLS_ECP_MONTGOMERY_ENABLED)
if( mbedtls_ecp_get_type( grp ) == MBEDTLS_ECP_TYPE_MONTGOMERY )
return( ecp_check_pubkey_mx( grp, pt ) );
#endif
-#if defined(ECP_SHORTWEIERSTRASS)
+#if defined(MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED)
if( mbedtls_ecp_get_type( grp ) == MBEDTLS_ECP_TYPE_SHORT_WEIERSTRASS )
return( ecp_check_pubkey_sw( grp, pt ) );
#endif
@@ -2756,7 +3081,7 @@
ECP_VALIDATE_RET( grp != NULL );
ECP_VALIDATE_RET( d != NULL );
-#if defined(ECP_MONTGOMERY)
+#if defined(MBEDTLS_ECP_MONTGOMERY_ENABLED)
if( mbedtls_ecp_get_type( grp ) == MBEDTLS_ECP_TYPE_MONTGOMERY )
{
/* see RFC 7748 sec. 5 para. 5 */
@@ -2771,8 +3096,8 @@
return( 0 );
}
-#endif /* ECP_MONTGOMERY */
-#if defined(ECP_SHORTWEIERSTRASS)
+#endif /* MBEDTLS_ECP_MONTGOMERY_ENABLED */
+#if defined(MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED)
if( mbedtls_ecp_get_type( grp ) == MBEDTLS_ECP_TYPE_SHORT_WEIERSTRASS )
{
/* see SEC1 3.2 */
@@ -2782,11 +3107,61 @@
else
return( 0 );
}
-#endif /* ECP_SHORTWEIERSTRASS */
+#endif /* MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED */
return( MBEDTLS_ERR_ECP_BAD_INPUT_DATA );
}
+#if defined(MBEDTLS_ECP_MONTGOMERY_ENABLED)
+MBEDTLS_STATIC_TESTABLE
+int mbedtls_ecp_gen_privkey_mx( size_t high_bit,
+ mbedtls_mpi *d,
+ int (*f_rng)(void *, unsigned char *, size_t),
+ void *p_rng )
+{
+ int ret = MBEDTLS_ERR_ECP_BAD_INPUT_DATA;
+ size_t n_random_bytes = high_bit / 8 + 1;
+
+ /* [Curve25519] page 5 */
+ /* Generate a (high_bit+1)-bit random number by generating just enough
+ * random bytes, then shifting out extra bits from the top (necessary
+ * when (high_bit+1) is not a multiple of 8). */
+ MBEDTLS_MPI_CHK( mbedtls_mpi_fill_random( d, n_random_bytes,
+ f_rng, p_rng ) );
+ MBEDTLS_MPI_CHK( mbedtls_mpi_shift_r( d, 8 * n_random_bytes - high_bit - 1 ) );
+
+ MBEDTLS_MPI_CHK( mbedtls_mpi_set_bit( d, high_bit, 1 ) );
+
+ /* Make sure the last two bits are unset for Curve448, three bits for
+ Curve25519 */
+ MBEDTLS_MPI_CHK( mbedtls_mpi_set_bit( d, 0, 0 ) );
+ MBEDTLS_MPI_CHK( mbedtls_mpi_set_bit( d, 1, 0 ) );
+ if( high_bit == 254 )
+ {
+ MBEDTLS_MPI_CHK( mbedtls_mpi_set_bit( d, 2, 0 ) );
+ }
+
+cleanup:
+ return( ret );
+}
+#endif /* MBEDTLS_ECP_MONTGOMERY_ENABLED */
+
+#if defined(MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED)
+static int mbedtls_ecp_gen_privkey_sw(
+ const mbedtls_mpi *N, mbedtls_mpi *d,
+ int (*f_rng)(void *, unsigned char *, size_t), void *p_rng )
+{
+ int ret = mbedtls_mpi_random( d, 1, N, f_rng, p_rng );
+ switch( ret )
+ {
+ case MBEDTLS_ERR_MPI_NOT_ACCEPTABLE:
+ return( MBEDTLS_ERR_ECP_RANDOM_FAILED );
+ default:
+ return( ret );
+ }
+}
+#endif /* MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED */
+
/*
* Generate a private key
*/
@@ -2795,86 +3170,21 @@
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng )
{
- int ret = MBEDTLS_ERR_ECP_BAD_INPUT_DATA;
- size_t n_size;
-
ECP_VALIDATE_RET( grp != NULL );
ECP_VALIDATE_RET( d != NULL );
ECP_VALIDATE_RET( f_rng != NULL );
- n_size = ( grp->nbits + 7 ) / 8;
-
-#if defined(ECP_MONTGOMERY)
+#if defined(MBEDTLS_ECP_MONTGOMERY_ENABLED)
if( mbedtls_ecp_get_type( grp ) == MBEDTLS_ECP_TYPE_MONTGOMERY )
- {
- /* [M225] page 5 */
- size_t b;
+ return( mbedtls_ecp_gen_privkey_mx( grp->nbits, d, f_rng, p_rng ) );
+#endif /* MBEDTLS_ECP_MONTGOMERY_ENABLED */
- do {
- MBEDTLS_MPI_CHK( mbedtls_mpi_fill_random( d, n_size, f_rng, p_rng ) );
- } while( mbedtls_mpi_bitlen( d ) == 0);
-
- /* Make sure the most significant bit is nbits */
- b = mbedtls_mpi_bitlen( d ) - 1; /* mbedtls_mpi_bitlen is one-based */
- if( b > grp->nbits )
- MBEDTLS_MPI_CHK( mbedtls_mpi_shift_r( d, b - grp->nbits ) );
- else
- MBEDTLS_MPI_CHK( mbedtls_mpi_set_bit( d, grp->nbits, 1 ) );
-
- /* Make sure the last two bits are unset for Curve448, three bits for
- Curve25519 */
- MBEDTLS_MPI_CHK( mbedtls_mpi_set_bit( d, 0, 0 ) );
- MBEDTLS_MPI_CHK( mbedtls_mpi_set_bit( d, 1, 0 ) );
- if( grp->nbits == 254 )
- {
- MBEDTLS_MPI_CHK( mbedtls_mpi_set_bit( d, 2, 0 ) );
- }
- }
-#endif /* ECP_MONTGOMERY */
-
-#if defined(ECP_SHORTWEIERSTRASS)
+#if defined(MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED)
if( mbedtls_ecp_get_type( grp ) == MBEDTLS_ECP_TYPE_SHORT_WEIERSTRASS )
- {
- /* SEC1 3.2.1: Generate d such that 1 <= n < N */
- int count = 0;
- unsigned cmp = 0;
+ return( mbedtls_ecp_gen_privkey_sw( &grp->N, d, f_rng, p_rng ) );
+#endif /* MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED */
- /*
- * Match the procedure given in RFC 6979 (deterministic ECDSA):
- * - use the same byte ordering;
- * - keep the leftmost nbits bits of the generated octet string;
- * - try until result is in the desired range.
- * This also avoids any biais, which is especially important for ECDSA.
- */
- do
- {
- MBEDTLS_MPI_CHK( mbedtls_mpi_fill_random( d, n_size, f_rng, p_rng ) );
- MBEDTLS_MPI_CHK( mbedtls_mpi_shift_r( d, 8 * n_size - grp->nbits ) );
-
- /*
- * Each try has at worst a probability 1/2 of failing (the msb has
- * a probability 1/2 of being 0, and then the result will be < N),
- * so after 30 tries failure probability is a most 2**(-30).
- *
- * For most curves, 1 try is enough with overwhelming probability,
- * since N starts with a lot of 1s in binary, but some curves
- * such as secp224k1 are actually very close to the worst case.
- */
- if( ++count > 30 )
- return( MBEDTLS_ERR_ECP_RANDOM_FAILED );
-
- ret = mbedtls_mpi_lt_mpi_ct( d, &grp->N, &cmp );
- if( ret != 0 )
- {
- goto cleanup;
- }
- }
- while( mbedtls_mpi_cmp_int( d, 1 ) < 0 || cmp != 1 );
- }
-#endif /* ECP_SHORTWEIERSTRASS */
-
-cleanup:
- return( ret );
+ return( MBEDTLS_ERR_ECP_BAD_INPUT_DATA );
}
/*
@@ -2949,7 +3259,7 @@
ret = MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE;
-#if defined(ECP_MONTGOMERY)
+#if defined(MBEDTLS_ECP_MONTGOMERY_ENABLED)
if( mbedtls_ecp_get_type( &key->grp ) == MBEDTLS_ECP_TYPE_MONTGOMERY )
{
/*
@@ -2984,7 +3294,7 @@
}
#endif
-#if defined(ECP_SHORTWEIERSTRASS)
+#if defined(MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED)
if( mbedtls_ecp_get_type( &key->grp ) == MBEDTLS_ECP_TYPE_SHORT_WEIERSTRASS )
{
MBEDTLS_MPI_CHK( mbedtls_mpi_read_binary( &key->d, buf, buflen ) );
@@ -3002,6 +3312,45 @@
}
/*
+ * Write a private key.
+ */
+int mbedtls_ecp_write_key( mbedtls_ecp_keypair *key,
+ unsigned char *buf, size_t buflen )
+{
+ int ret = MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE;
+
+ ECP_VALIDATE_RET( key != NULL );
+ ECP_VALIDATE_RET( buf != NULL );
+
+#if defined(MBEDTLS_ECP_MONTGOMERY_ENABLED)
+ if( mbedtls_ecp_get_type( &key->grp ) == MBEDTLS_ECP_TYPE_MONTGOMERY )
+ {
+ if( key->grp.id == MBEDTLS_ECP_DP_CURVE25519 )
+ {
+ if( buflen < ECP_CURVE25519_KEY_SIZE )
+ return MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL;
+
+ MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary_le( &key->d, buf, buflen ) );
+ }
+ else
+ ret = MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE;
+ }
+
+#endif
+#if defined(MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED)
+ if( mbedtls_ecp_get_type( &key->grp ) == MBEDTLS_ECP_TYPE_SHORT_WEIERSTRASS )
+ {
+ MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( &key->d, buf, buflen ) );
+ }
+
+#endif
+cleanup:
+
+ return( ret );
+}
+
+
+/*
* Check a public-private key pair
*/
int mbedtls_ecp_check_pub_priv( const mbedtls_ecp_keypair *pub, const mbedtls_ecp_keypair *prv )
@@ -3047,33 +3396,141 @@
#if defined(MBEDTLS_SELF_TEST)
+/* Adjust the exponent to be a valid private point for the specified curve.
+ * This is sometimes necessary because we use a single set of exponents
+ * for all curves but the validity of values depends on the curve. */
+static int self_test_adjust_exponent( const mbedtls_ecp_group *grp,
+ mbedtls_mpi *m )
+{
+ int ret = 0;
+ switch( grp->id )
+ {
+ /* If Curve25519 is available, then that's what we use for the
+ * Montgomery test, so we don't need the adjustment code. */
+#if ! defined(MBEDTLS_ECP_DP_CURVE25519_ENABLED)
+#if defined(MBEDTLS_ECP_DP_CURVE448_ENABLED)
+ case MBEDTLS_ECP_DP_CURVE448:
+ /* Move highest bit from 254 to N-1. Setting bit N-1 is
+ * necessary to enforce the highest-bit-set constraint. */
+ MBEDTLS_MPI_CHK( mbedtls_mpi_set_bit( m, 254, 0 ) );
+ MBEDTLS_MPI_CHK( mbedtls_mpi_set_bit( m, grp->nbits, 1 ) );
+ /* Copy second-highest bit from 253 to N-2. This is not
+ * necessary but improves the test variety a bit. */
+ MBEDTLS_MPI_CHK(
+ mbedtls_mpi_set_bit( m, grp->nbits - 1,
+ mbedtls_mpi_get_bit( m, 253 ) ) );
+ break;
+#endif
+#endif /* ! defined(MBEDTLS_ECP_DP_CURVE25519_ENABLED) */
+ default:
+ /* Non-Montgomery curves and Curve25519 need no adjustment. */
+ (void) grp;
+ (void) m;
+ goto cleanup;
+ }
+cleanup:
+ return( ret );
+}
+
+/* Calculate R = m.P for each m in exponents. Check that the number of
+ * basic operations doesn't depend on the value of m. */
+static int self_test_point( int verbose,
+ mbedtls_ecp_group *grp,
+ mbedtls_ecp_point *R,
+ mbedtls_mpi *m,
+ const mbedtls_ecp_point *P,
+ const char *const *exponents,
+ size_t n_exponents )
+{
+ int ret = 0;
+ size_t i = 0;
+ unsigned long add_c_prev, dbl_c_prev, mul_c_prev;
+ add_count = 0;
+ dbl_count = 0;
+ mul_count = 0;
+
+ MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( m, 16, exponents[0] ) );
+ MBEDTLS_MPI_CHK( self_test_adjust_exponent( grp, m ) );
+ MBEDTLS_MPI_CHK( mbedtls_ecp_mul( grp, R, m, P, NULL, NULL ) );
+
+ for( i = 1; i < n_exponents; i++ )
+ {
+ add_c_prev = add_count;
+ dbl_c_prev = dbl_count;
+ mul_c_prev = mul_count;
+ add_count = 0;
+ dbl_count = 0;
+ mul_count = 0;
+
+ MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( m, 16, exponents[i] ) );
+ MBEDTLS_MPI_CHK( self_test_adjust_exponent( grp, m ) );
+ MBEDTLS_MPI_CHK( mbedtls_ecp_mul( grp, R, m, P, NULL, NULL ) );
+
+ if( add_count != add_c_prev ||
+ dbl_count != dbl_c_prev ||
+ mul_count != mul_c_prev )
+ {
+ ret = 1;
+ break;
+ }
+ }
+
+cleanup:
+ if( verbose != 0 )
+ {
+ if( ret != 0 )
+ mbedtls_printf( "failed (%u)\n", (unsigned int) i );
+ else
+ mbedtls_printf( "passed\n" );
+ }
+ return( ret );
+}
+
/*
* Checkup routine
*/
int mbedtls_ecp_self_test( int verbose )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
- size_t i;
mbedtls_ecp_group grp;
mbedtls_ecp_point R, P;
mbedtls_mpi m;
- unsigned long add_c_prev, dbl_c_prev, mul_c_prev;
- /* exponents especially adapted for secp192r1 */
- const char *exponents[] =
+
+#if defined(MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED)
+ /* Exponents especially adapted for secp192k1, which has the lowest
+ * order n of all supported curves (secp192r1 is in a slightly larger
+ * field but the order of its base point is slightly smaller). */
+ const char *sw_exponents[] =
{
"000000000000000000000000000000000000000000000001", /* one */
- "FFFFFFFFFFFFFFFFFFFFFFFF99DEF836146BC9B1B4D22830", /* N - 1 */
+ "FFFFFFFFFFFFFFFFFFFFFFFE26F2FC170F69466A74DEFD8C", /* n - 1 */
"5EA6F389A38B8BC81E767753B15AA5569E1782E30ABE7D25", /* random */
"400000000000000000000000000000000000000000000000", /* one and zeros */
"7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", /* all ones */
"555555555555555555555555555555555555555555555555", /* 101010... */
};
+#endif /* MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED */
+#if defined(MBEDTLS_ECP_MONTGOMERY_ENABLED)
+ const char *m_exponents[] =
+ {
+ /* Valid private values for Curve25519. In a build with Curve448
+ * but not Curve25519, they will be adjusted in
+ * self_test_adjust_exponent(). */
+ "4000000000000000000000000000000000000000000000000000000000000000",
+ "5C3C3C3C3C3C3C3C3C3C3C3C3C3C3C3C3C3C3C3C3C3C3C3C3C3C3C3C3C3C3C30",
+ "5715ECCE24583F7A7023C24164390586842E816D7280A49EF6DF4EAE6B280BF8",
+ "41A2B017516F6D254E1F002BCCBADD54BE30F8CEC737A0E912B4963B6BA74460",
+ "5555555555555555555555555555555555555555555555555555555555555550",
+ "7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF8",
+ };
+#endif /* MBEDTLS_ECP_MONTGOMERY_ENABLED */
mbedtls_ecp_group_init( &grp );
mbedtls_ecp_point_init( &R );
mbedtls_ecp_point_init( &P );
mbedtls_mpi_init( &m );
+#if defined(MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED)
/* Use secp192r1 if available, or any available curve */
#if defined(MBEDTLS_ECP_DP_SECP192R1_ENABLED)
MBEDTLS_MPI_CHK( mbedtls_ecp_group_load( &grp, MBEDTLS_ECP_DP_SECP192R1 ) );
@@ -3082,86 +3539,53 @@
#endif
if( verbose != 0 )
- mbedtls_printf( " ECP test #1 (constant op_count, base point G): " );
-
+ mbedtls_printf( " ECP SW test #1 (constant op_count, base point G): " );
/* Do a dummy multiplication first to trigger precomputation */
MBEDTLS_MPI_CHK( mbedtls_mpi_lset( &m, 2 ) );
MBEDTLS_MPI_CHK( mbedtls_ecp_mul( &grp, &P, &m, &grp.G, NULL, NULL ) );
-
- add_count = 0;
- dbl_count = 0;
- mul_count = 0;
- MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &m, 16, exponents[0] ) );
- MBEDTLS_MPI_CHK( mbedtls_ecp_mul( &grp, &R, &m, &grp.G, NULL, NULL ) );
-
- for( i = 1; i < sizeof( exponents ) / sizeof( exponents[0] ); i++ )
- {
- add_c_prev = add_count;
- dbl_c_prev = dbl_count;
- mul_c_prev = mul_count;
- add_count = 0;
- dbl_count = 0;
- mul_count = 0;
-
- MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &m, 16, exponents[i] ) );
- MBEDTLS_MPI_CHK( mbedtls_ecp_mul( &grp, &R, &m, &grp.G, NULL, NULL ) );
-
- if( add_count != add_c_prev ||
- dbl_count != dbl_c_prev ||
- mul_count != mul_c_prev )
- {
- if( verbose != 0 )
- mbedtls_printf( "failed (%u)\n", (unsigned int) i );
-
- ret = 1;
- goto cleanup;
- }
- }
+ ret = self_test_point( verbose,
+ &grp, &R, &m, &grp.G,
+ sw_exponents,
+ sizeof( sw_exponents ) / sizeof( sw_exponents[0] ));
+ if( ret != 0 )
+ goto cleanup;
if( verbose != 0 )
- mbedtls_printf( "passed\n" );
-
- if( verbose != 0 )
- mbedtls_printf( " ECP test #2 (constant op_count, other point): " );
+ mbedtls_printf( " ECP SW test #2 (constant op_count, other point): " );
/* We computed P = 2G last time, use it */
+ ret = self_test_point( verbose,
+ &grp, &R, &m, &P,
+ sw_exponents,
+ sizeof( sw_exponents ) / sizeof( sw_exponents[0] ));
+ if( ret != 0 )
+ goto cleanup;
- add_count = 0;
- dbl_count = 0;
- mul_count = 0;
- MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &m, 16, exponents[0] ) );
- MBEDTLS_MPI_CHK( mbedtls_ecp_mul( &grp, &R, &m, &P, NULL, NULL ) );
+ mbedtls_ecp_group_free( &grp );
+ mbedtls_ecp_point_free( &R );
+#endif /* MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED */
- for( i = 1; i < sizeof( exponents ) / sizeof( exponents[0] ); i++ )
- {
- add_c_prev = add_count;
- dbl_c_prev = dbl_count;
- mul_c_prev = mul_count;
- add_count = 0;
- dbl_count = 0;
- mul_count = 0;
-
- MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &m, 16, exponents[i] ) );
- MBEDTLS_MPI_CHK( mbedtls_ecp_mul( &grp, &R, &m, &P, NULL, NULL ) );
-
- if( add_count != add_c_prev ||
- dbl_count != dbl_c_prev ||
- mul_count != mul_c_prev )
- {
- if( verbose != 0 )
- mbedtls_printf( "failed (%u)\n", (unsigned int) i );
-
- ret = 1;
- goto cleanup;
- }
- }
-
+#if defined(MBEDTLS_ECP_MONTGOMERY_ENABLED)
if( verbose != 0 )
- mbedtls_printf( "passed\n" );
+ mbedtls_printf( " ECP Montgomery test (constant op_count): " );
+#if defined(MBEDTLS_ECP_DP_CURVE25519_ENABLED)
+ MBEDTLS_MPI_CHK( mbedtls_ecp_group_load( &grp, MBEDTLS_ECP_DP_CURVE25519 ) );
+#elif defined(MBEDTLS_ECP_DP_CURVE448_ENABLED)
+ MBEDTLS_MPI_CHK( mbedtls_ecp_group_load( &grp, MBEDTLS_ECP_DP_CURVE448 ) );
+#else
+#error "MBEDTLS_ECP_MONTGOMERY_ENABLED is defined, but no curve is supported for self-test"
+#endif
+ ret = self_test_point( verbose,
+ &grp, &R, &m, &grp.G,
+ m_exponents,
+ sizeof( m_exponents ) / sizeof( m_exponents[0] ));
+ if( ret != 0 )
+ goto cleanup;
+#endif /* MBEDTLS_ECP_MONTGOMERY_ENABLED */
cleanup:
if( ret < 0 && verbose != 0 )
- mbedtls_printf( "Unexpected error, return code = %08X\n", ret );
+ mbedtls_printf( "Unexpected error, return code = %08X\n", (unsigned int) ret );
mbedtls_ecp_group_free( &grp );
mbedtls_ecp_point_free( &R );