tinyCrypt: Initial commit towards ECDHE support

This commit is a first step towards using uECC for ECDH
during TLS handshakes.
This commit is contained in:
Jarno Lamsa 2019-04-04 18:32:56 +03:00 committed by Hanno Becker
parent 36ae758798
commit e12aafbdc7
4 changed files with 155 additions and 21 deletions

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@ -53,6 +53,11 @@
#include "ecjpake.h" #include "ecjpake.h"
#endif #endif
#if defined(MBEDTLS_USE_TINYCRYPT)
#include "tinycrypt/ecc.h"
#include "tinycrypt/ecc_dh.h"
#endif
#if ( defined(__ARMCC_VERSION) || defined(_MSC_VER) ) && \ #if ( defined(__ARMCC_VERSION) || defined(_MSC_VER) ) && \
!defined(inline) && !defined(__cplusplus) !defined(inline) && !defined(__cplusplus)
#define inline __inline #define inline __inline
@ -381,10 +386,17 @@ struct mbedtls_ssl_handshake_params
size_t ecjpake_cache_len; /*!< Length of cached data */ size_t ecjpake_cache_len; /*!< Length of cached data */
#endif #endif
#endif /* MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */ #endif /* MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */
#if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \ #if defined(MBEDTLS_ECDH_C) || \
defined(MBEDTLS_ECDSA_C) || \
defined(MBEDTLS_USE_TINYCRYPT) || \
defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
uint16_t curve_tls_id; /*!< TLS ID of EC for ECDHE. */ uint16_t curve_tls_id; /*!< TLS ID of EC for ECDHE. */
#endif #endif
#if defined(MBEDTLS_USE_TINYCRYPT)
uint8_t ecdh_privkey[NUM_ECC_BYTES];
uint8_t ecdh_ownpubkey[2*NUM_ECC_BYTES];
uint8_t ecdh_peerkey[2*NUM_ECC_BYTES];
#endif /* MBEDTLS_USE_TINYCRYPT */
#if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED) #if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED)
unsigned char *psk; /*!< PSK from the callback */ unsigned char *psk; /*!< PSK from the callback */
size_t psk_len; /*!< Length of PSK from callback */ size_t psk_len; /*!< Length of PSK from callback */
@ -890,6 +902,10 @@ int mbedtls_ssl_handle_message_type( mbedtls_ssl_context *ssl );
int mbedtls_ssl_prepare_handshake_record( mbedtls_ssl_context *ssl ); int mbedtls_ssl_prepare_handshake_record( mbedtls_ssl_context *ssl );
void mbedtls_ssl_update_handshake_status( mbedtls_ssl_context *ssl ); void mbedtls_ssl_update_handshake_status( mbedtls_ssl_context *ssl );
#if defined(MBEDTLS_USE_TINYCRYPT)
int mbetls_uecc_rng_wrapper( uint8_t *dest, unsigned int size );
#endif
/** /**
* \brief Update record layer * \brief Update record layer
* *

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@ -250,7 +250,9 @@ static void ssl_write_signature_algorithms_ext( mbedtls_ssl_context *ssl,
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 && #endif /* MBEDTLS_SSL_PROTO_TLS1_2 &&
MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED */ MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED */
#if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \ #if defined(MBEDTLS_ECDH_C) || \
defined(MBEDTLS_ECDSA_C) || \
defined(MBEDTLS_USE_TINYCRYPT) || \
defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
static size_t ssl_get_ec_curve_list_length( mbedtls_ssl_context *ssl ) static size_t ssl_get_ec_curve_list_length( mbedtls_ssl_context *ssl )
{ {
@ -332,7 +334,7 @@ static void ssl_write_supported_point_formats_ext( mbedtls_ssl_context *ssl,
*olen = 6; *olen = 6;
} }
#endif /* MBEDTLS_ECDH_C || MBEDTLS_ECDSA_C || #endif /* MBEDTLS_ECDH_C || MBEDTLS_ECDSA_C || MBEDTLS_USE_TINYCRYPT ||
MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */ MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) #if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
@ -1073,7 +1075,9 @@ static int ssl_write_client_hello( mbedtls_ssl_context *ssl )
ext_len += olen; ext_len += olen;
#endif #endif
#if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \ #if defined(MBEDTLS_ECDH_C) || \
defined(MBEDTLS_ECDSA_C) || \
defined(MBEDTLS_USE_TINYCRYPT) || \
defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
if( uses_ec ) if( uses_ec )
{ {
@ -1374,8 +1378,10 @@ static int ssl_parse_session_ticket_ext( mbedtls_ssl_context *ssl,
} }
#endif /* MBEDTLS_SSL_SESSION_TICKETS */ #endif /* MBEDTLS_SSL_SESSION_TICKETS */
#if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \ #if defined(MBEDTLS_ECDH_C) || \
defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) defined(MBEDTLS_ECDSA_C) || \
defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) || \
defined(MBEDTLS_USE_TINYCRYPT)
static int ssl_parse_supported_point_formats_ext( mbedtls_ssl_context *ssl, static int ssl_parse_supported_point_formats_ext( mbedtls_ssl_context *ssl,
const unsigned char *buf, const unsigned char *buf,
size_t len ) size_t len )
@ -1417,7 +1423,7 @@ static int ssl_parse_supported_point_formats_ext( mbedtls_ssl_context *ssl,
MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE ); MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE );
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO ); return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
} }
#endif /* MBEDTLS_ECDH_C || MBEDTLS_ECDSA_C || #endif /* MBEDTLS_ECDH_C || MBEDTLS_ECDSA_C || MBEDTLS_USE_TINYCRYPT ||
MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */ MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) #if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
@ -3521,10 +3527,42 @@ static int ssl_out_client_key_exchange_write( mbedtls_ssl_context *ssl,
} }
else else
#endif /* MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED */ #endif /* MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \ #if defined(MBEDTLS_USE_TINYCRYPT)
defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) || \ if( mbedtls_ssl_suite_get_key_exchange( ciphersuite_info )
defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED) || \ == MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA)
defined(MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED) {
const struct uECC_Curve_t * uecc_curve = uECC_secp256r1();
uECC_set_rng( &mbetls_uecc_rng_wrapper );
if( !uECC_make_key( ssl->handshake->ecdh_ownpubkey,
ssl->handshake->ecdh_privkey,
uecc_curve ) )
{
return( MBEDTLS_ERR_SSL_HW_ACCEL_FAILED );
}
if( !uECC_shared_secret( ssl->handshake->ecdh_peerkey,
ssl->handshake->ecdh_privkey,
ssl->handshake->premaster,
uecc_curve ) )
{
return( MBEDTLS_ERR_SSL_HW_ACCEL_FAILED );
}
/* TODO: Write the client share. */
((void) p);
((void) end);
((void) ret);
((void) n);
mbedtls_platform_zeroize( ssl->handshake->ecdh_privkey, NUM_ECC_BYTES );
}
else
#elif defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED)
if( mbedtls_ssl_suite_get_key_exchange( ciphersuite_info ) if( mbedtls_ssl_suite_get_key_exchange( ciphersuite_info )
== MBEDTLS_KEY_EXCHANGE_ECDHE_RSA || == MBEDTLS_KEY_EXCHANGE_ECDHE_RSA ||
mbedtls_ssl_suite_get_key_exchange( ciphersuite_info ) mbedtls_ssl_suite_get_key_exchange( ciphersuite_info )

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@ -276,7 +276,9 @@ static int ssl_parse_signature_algorithms_ext( mbedtls_ssl_context *ssl,
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 && #endif /* MBEDTLS_SSL_PROTO_TLS1_2 &&
MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED */ MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED */
#if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \ #if defined(MBEDTLS_ECDH_C) || \
defined(MBEDTLS_ECDSA_C) || \
defined(MBEDTLS_USE_TINYCRYPT) || \
defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
static int ssl_parse_supported_elliptic_curves( mbedtls_ssl_context *ssl, static int ssl_parse_supported_elliptic_curves( mbedtls_ssl_context *ssl,
const unsigned char *buf, size_t len, const unsigned char *buf, size_t len,
@ -364,7 +366,7 @@ static int ssl_parse_supported_point_formats( mbedtls_ssl_context *ssl,
return( 0 ); return( 0 );
} }
#endif /* MBEDTLS_ECDH_C || MBEDTLS_ECDSA_C || #endif /* MBEDTLS_ECDH_C || MBEDTLS_ECDSA_C || MBEDTLS_USE_TINYCRYPT
MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */ MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) #if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
@ -972,7 +974,8 @@ static int ssl_ciphersuite_is_match( mbedtls_ssl_context *ssl,
} }
#endif #endif
#if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) #if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \
defined(MBEDTLS_USE_TINYCRYPT)
if( mbedtls_ssl_ciphersuite_uses_ec( suite_info ) && if( mbedtls_ssl_ciphersuite_uses_ec( suite_info ) &&
ssl->handshake->curve_tls_id == 0 ) ssl->handshake->curve_tls_id == 0 )
{ {
@ -1922,8 +1925,10 @@ read_record_header:
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 && #endif /* MBEDTLS_SSL_PROTO_TLS1_2 &&
MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED */ MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED */
#if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \ #if defined(MBEDTLS_ECDH_C) || \
defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) defined(MBEDTLS_ECDSA_C) || \
defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) || \
defined(MBEDTLS_USE_TINYCRYPT)
case MBEDTLS_TLS_EXT_SUPPORTED_ELLIPTIC_CURVES: case MBEDTLS_TLS_EXT_SUPPORTED_ELLIPTIC_CURVES:
MBEDTLS_SSL_DEBUG_MSG( 3, ( "found supported elliptic curves extension" ) ); MBEDTLS_SSL_DEBUG_MSG( 3, ( "found supported elliptic curves extension" ) );
@ -1944,7 +1949,8 @@ read_record_header:
return( ret ); return( ret );
break; break;
#endif /* MBEDTLS_ECDH_C || MBEDTLS_ECDSA_C || #endif /* MBEDTLS_ECDH_C || MBEDTLS_ECDSA_C ||
MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */ MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED ||
MBEDTLS_USE_TINYCRYPT */
#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) #if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
case MBEDTLS_TLS_EXT_ECJPAKE_KKPP: case MBEDTLS_TLS_EXT_ECJPAKE_KKPP:
@ -2539,7 +2545,8 @@ static void ssl_write_max_fragment_length_ext( mbedtls_ssl_context *ssl,
#endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */ #endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */
#if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \ #if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \
defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) || \
defined(MBEDTLS_USE_TINYCRYPT)
static void ssl_write_supported_point_formats_ext( mbedtls_ssl_context *ssl, static void ssl_write_supported_point_formats_ext( mbedtls_ssl_context *ssl,
unsigned char *buf, unsigned char *buf,
size_t *olen ) size_t *olen )
@ -2936,7 +2943,8 @@ static int ssl_write_server_hello( mbedtls_ssl_context *ssl )
#endif #endif
#if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \ #if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \
defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) || \
defined(MBEDTLS_USE_TINYCRYPT)
if ( mbedtls_ssl_ciphersuite_uses_ec( if ( mbedtls_ssl_ciphersuite_uses_ec(
mbedtls_ssl_ciphersuite_from_id( mbedtls_ssl_ciphersuite_from_id(
mbedtls_ssl_session_get_ciphersuite( ssl->session_negotiate ) ) ) ) mbedtls_ssl_session_get_ciphersuite( ssl->session_negotiate ) ) ) )
@ -3243,6 +3251,9 @@ static int ssl_prepare_server_key_exchange( mbedtls_ssl_context *ssl,
unsigned char *dig_signed = NULL; unsigned char *dig_signed = NULL;
#endif /* MBEDTLS_KEY_EXCHANGE__WITH_SERVER_SIGNATURE__ENABLED */ #endif /* MBEDTLS_KEY_EXCHANGE__WITH_SERVER_SIGNATURE__ENABLED */
#endif /* MBEDTLS_KEY_EXCHANGE__SOME_PFS__ENABLED */ #endif /* MBEDTLS_KEY_EXCHANGE__SOME_PFS__ENABLED */
#if defined(MBEDTLS_USE_TINYCRYPT)
const struct uECC_Curve_t * uecc_curve = uECC_secp256r1();
#endif
(void) ciphersuite_info; /* unused in some configurations */ (void) ciphersuite_info; /* unused in some configurations */
#if !defined(MBEDTLS_KEY_EXCHANGE__WITH_SERVER_SIGNATURE__ENABLED) #if !defined(MBEDTLS_KEY_EXCHANGE__WITH_SERVER_SIGNATURE__ENABLED)
@ -3290,8 +3301,10 @@ static int ssl_prepare_server_key_exchange( mbedtls_ssl_context *ssl,
**/ **/
#if defined(MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED) || \ #if defined(MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED) defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED)
if( mbedtls_ssl_suite_get_key_exchange( ciphersuite_info ) == MBEDTLS_KEY_EXCHANGE_DHE_PSK || if( mbedtls_ssl_suite_get_key_exchange( ciphersuite_info ) ==
mbedtls_ssl_suite_get_key_exchange( ciphersuite_info ) == MBEDTLS_KEY_EXCHANGE_ECDHE_PSK ) MBEDTLS_KEY_EXCHANGE_DHE_PSK ||
mbedtls_ssl_suite_get_key_exchange( ciphersuite_info ) ==
MBEDTLS_KEY_EXCHANGE_ECDHE_PSK )
{ {
ssl->out_msg[ssl->out_msglen++] = 0x00; ssl->out_msg[ssl->out_msglen++] = 0x00;
ssl->out_msg[ssl->out_msglen++] = 0x00; ssl->out_msg[ssl->out_msglen++] = 0x00;
@ -3369,6 +3382,43 @@ static int ssl_prepare_server_key_exchange( mbedtls_ssl_context *ssl,
* ECPoint public; * ECPoint public;
* } ServerECDHParams; * } ServerECDHParams;
*/ */
#if defined(MBEDTLS_USE_TINYCRYPT)
uECC_set_rng( &mbetls_uecc_rng_wrapper );
if( ssl->handshake->curve_tls_id != 23 )
return( MBEDTLS_ERR_SSL_NO_CIPHER_CHOSEN );
if( !uECC_make_key( ssl->handshake->ecdh_ownpubkey,
ssl->handshake->ecdh_privkey,
uecc_curve ) )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "Key creation failed" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
/*
* First byte is curve_type, always named_curve
*/
ssl->out_msg[ssl->out_msglen++] = MBEDTLS_ECP_TLS_NAMED_CURVE;
/*
* Next two bytes are the namedcurve value
*/
ssl->out_msg[ssl->out_msglen++] = ssl->handshake->curve_tls_id >> 8;
ssl->out_msg[ssl->out_msglen++] = ssl->handshake->curve_tls_id & 0xFF;
/* Write the public key length */
ssl->out_msg[ssl->out_msglen++] = 2*NUM_ECC_BYTES;
memcpy( &ssl->out_msg[ssl->out_msglen],
ssl->handshake->ecdh_ownpubkey,
2*NUM_ECC_BYTES );
ssl->out_msglen += 2*NUM_ECC_BYTES;
#else /* MBEDTLS_USE_TINYCRYPT */
const mbedtls_ecp_curve_info *curve = const mbedtls_ecp_curve_info *curve =
mbedtls_ecp_curve_info_from_tls_id( ssl->handshake->curve_tls_id ); mbedtls_ecp_curve_info_from_tls_id( ssl->handshake->curve_tls_id );
int ret; int ret;
@ -3407,6 +3457,9 @@ static int ssl_prepare_server_key_exchange( mbedtls_ssl_context *ssl,
MBEDTLS_SSL_DEBUG_ECDH( 3, &ssl->handshake->ecdh_ctx, MBEDTLS_SSL_DEBUG_ECDH( 3, &ssl->handshake->ecdh_ctx,
MBEDTLS_DEBUG_ECDH_Q ); MBEDTLS_DEBUG_ECDH_Q );
#endif /* MBEDTLS_USE_TINYCRYPT */
} }
#endif /* MBEDTLS_KEY_EXCHANGE__SOME__ECDHE_ENABLED */ #endif /* MBEDTLS_KEY_EXCHANGE__SOME__ECDHE_ENABLED */
@ -4140,6 +4193,26 @@ static int ssl_in_client_key_exchange_parse( mbedtls_ssl_context *ssl,
} }
else else
#endif /* MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED */ #endif /* MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED */
#if defined(MBEDTLS_USE_TINYCRYPT)
if( mbedtls_ssl_suite_get_key_exchange( ciphersuite_info )
== MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA ||
mbedtls_ssl_suite_get_key_exchange( ciphersuite_info )
== MBEDTLS_KEY_EXCHANGE_ECDHE_RSA )
{
const struct uECC_Curve_t * uecc_curve = uECC_secp256r1();
/* TODO: Parse the client's key share. */
if( !uECC_shared_secret( ssl->handshake->ecdh_peerkey,
ssl->handshake->ecdh_privkey,
ssl->handshake->premaster,
uecc_curve ) )
{
return( MBEDTLS_ERR_SSL_HW_ACCEL_FAILED );
}
}
else
#endif
#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \ #if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) || \ defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED) || \ defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED) || \

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@ -12165,6 +12165,13 @@ unsigned char mbedtls_ssl_hash_from_md_alg( int md )
} }
} }
#if defined(MBEDTLS_USE_TINYCRYPT)
int mbetls_uecc_rng_wrapper( uint8_t *dest, unsigned int size )
{
return( mbedtls_ssl_conf_rng_func( NULL, dest, size ) );
}
#endif /* MBEDTLS_USE_TINYCRYPT */
#if defined(MBEDTLS_ECP_C) #if defined(MBEDTLS_ECP_C)
/* /*
* Check if a curve proposed by the peer is in our list. * Check if a curve proposed by the peer is in our list.