Add client-side support for ECDH key exchanges

This commit is contained in:
Manuel Pégourié-Gonnard 2013-12-11 17:45:46 +01:00
parent cdff3cfda3
commit d18cc57962
2 changed files with 97 additions and 18 deletions

View file

@ -1113,6 +1113,29 @@ static int ssl_parse_server_dh_params( ssl_context *ssl, unsigned char **p,
#endif /* POLARSSL_KEY_EXCHANGE_DHE_RSA_ENABLED || #endif /* POLARSSL_KEY_EXCHANGE_DHE_RSA_ENABLED ||
POLARSSL_KEY_EXCHANGE_DHE_PSK_ENABLED */ POLARSSL_KEY_EXCHANGE_DHE_PSK_ENABLED */
#if defined(POLARSSL_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \
defined(POLARSSL_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) || \
defined(POLARSSL_KEY_EXCHANGE_ECDHE_PSK_ENABLED) || \
defined(POLARSSL_KEY_EXCHANGE_ECDH_RSA_ENABLED) || \
defined(POLARSSL_KEY_EXCHANGE_ECDH_ECDSA_ENABLED)
static int ssl_check_server_ecdh_params( const ssl_context *ssl )
{
SSL_DEBUG_MSG( 2, ( "ECDH curve size: %d",
(int) ssl->handshake->ecdh_ctx.grp.nbits ) );
if( ssl->handshake->ecdh_ctx.grp.nbits < 163 ||
ssl->handshake->ecdh_ctx.grp.nbits > 521 )
{
return( -1 );
}
SSL_DEBUG_ECP( 3, "ECDH: Qp", &ssl->handshake->ecdh_ctx.Qp );
return( 0 );
}
#endif
#if defined(POLARSSL_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \ #if defined(POLARSSL_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \
defined(POLARSSL_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) || \ defined(POLARSSL_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) || \
defined(POLARSSL_KEY_EXCHANGE_ECDHE_PSK_ENABLED) defined(POLARSSL_KEY_EXCHANGE_ECDHE_PSK_ENABLED)
@ -1137,18 +1160,12 @@ static int ssl_parse_server_ecdh_params( ssl_context *ssl,
return( ret ); return( ret );
} }
SSL_DEBUG_MSG( 2, ( "ECDH curve size: %d", if( ssl_check_server_ecdh_params( ssl ) != 0 )
(int) ssl->handshake->ecdh_ctx.grp.nbits ) );
if( ssl->handshake->ecdh_ctx.grp.nbits < 163 ||
ssl->handshake->ecdh_ctx.grp.nbits > 521 )
{ {
SSL_DEBUG_MSG( 1, ( "bad server key exchange message (ECDH length)" ) ); SSL_DEBUG_MSG( 1, ( "bad server key exchange message (ECDH length)" ) );
return( POLARSSL_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE ); return( POLARSSL_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE );
} }
SSL_DEBUG_ECP( 3, "ECDH: Qp", &ssl->handshake->ecdh_ctx.Qp );
return( ret ); return( ret );
} }
#endif /* POLARSSL_KEY_EXCHANGE_ECDHE_RSA_ENABLED || #endif /* POLARSSL_KEY_EXCHANGE_ECDHE_RSA_ENABLED ||
@ -1307,6 +1324,41 @@ static int ssl_parse_signature_algorithm( ssl_context *ssl,
POLARSSL_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED */ POLARSSL_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED */
#endif /* POLARSSL_SSL_PROTO_TLS1_2 */ #endif /* POLARSSL_SSL_PROTO_TLS1_2 */
#if defined(POLARSSL_KEY_EXCHANGE_ECDH_RSA_ENABLED) || \
defined(POLARSSL_KEY_EXCHANGE_ECDH_ECDSA_ENABLED)
static int ssl_get_ecdh_params_from_cert( ssl_context *ssl )
{
int ret;
const ecp_keypair *peer_key;
if( ! pk_can_do( &ssl->session_negotiate->peer_cert->pk,
POLARSSL_PK_ECKEY ) )
{
SSL_DEBUG_MSG( 1, ( "server key not ECDH capable" ) );
return( POLARSSL_ERR_SSL_PK_TYPE_MISMATCH );
}
peer_key = pk_ec( ssl->session_negotiate->peer_cert->pk );
if( ( ret = ecdh_get_params( &ssl->handshake->ecdh_ctx, peer_key,
POLARSSL_ECDH_THEIRS ) ) != 0 )
{
SSL_DEBUG_RET( 1, ( "ecdh_get_params" ), ret );
return( ret );
}
if( ssl_check_server_ecdh_params( ssl ) != 0 )
{
SSL_DEBUG_MSG( 1, ( "bad server certificate (ECDH length)" ) );
return( POLARSSL_ERR_SSL_BAD_HS_CERTIFICATE );
}
return( ret );
}
#endif /* POLARSSL_KEY_EXCHANGE_ECDH_RSA_ENABLED) ||
POLARSSL_KEY_EXCHANGE_ECDH_ECDSA_ENABLED */
static int ssl_parse_server_key_exchange( ssl_context *ssl ) static int ssl_parse_server_key_exchange( ssl_context *ssl )
{ {
int ret; int ret;
@ -1335,6 +1387,21 @@ static int ssl_parse_server_key_exchange( ssl_context *ssl )
((void) end); ((void) end);
#endif #endif
#if defined(POLARSSL_KEY_EXCHANGE_ECDH_RSA_ENABLED) || \
defined(POLARSSL_KEY_EXCHANGE_ECDH_ECDSA_ENABLED)
if( ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_ECDH_RSA ||
ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_ECDH_ECDSA )
{
ssl_get_ecdh_params_from_cert( ssl );
SSL_DEBUG_MSG( 2, ( "<= skip parse server key exchange" ) );
ssl->state++;
return( 0 );
}
((void) p);
((void) end);
#endif
if( ( ret = ssl_read_record( ssl ) ) != 0 ) if( ( ret = ssl_read_record( ssl ) ) != 0 )
{ {
SSL_DEBUG_RET( 1, "ssl_read_record", ret ); SSL_DEBUG_RET( 1, "ssl_read_record", ret );
@ -1852,9 +1919,13 @@ static int ssl_write_client_key_exchange( ssl_context *ssl )
else else
#endif /* POLARSSL_KEY_EXCHANGE_DHE_RSA_ENABLED */ #endif /* POLARSSL_KEY_EXCHANGE_DHE_RSA_ENABLED */
#if defined(POLARSSL_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \ #if defined(POLARSSL_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \
defined(POLARSSL_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) defined(POLARSSL_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) || \
defined(POLARSSL_KEY_EXCHANGE_ECDH_RSA_ENABLED) || \
defined(POLARSSL_KEY_EXCHANGE_ECDH_ECDSA_ENABLED)
if( ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_ECDHE_RSA || if( ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_ECDHE_RSA ||
ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_ECDHE_ECDSA ) ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_ECDHE_ECDSA ||
ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_ECDH_RSA ||
ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_ECDH_ECDSA )
{ {
/* /*
* ECDH key exchange -- send client public value * ECDH key exchange -- send client public value
@ -1887,7 +1958,9 @@ static int ssl_write_client_key_exchange( ssl_context *ssl )
} }
else else
#endif /* POLARSSL_KEY_EXCHANGE_ECDHE_RSA_ENABLED || #endif /* POLARSSL_KEY_EXCHANGE_ECDHE_RSA_ENABLED ||
POLARSSL_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED */ POLARSSL_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED ||
POLARSSL_KEY_EXCHANGE_ECDH_RSA_ENABLED ||
POLARSSL_KEY_EXCHANGE_ECDH_ECDSA_ENABLED */
#if defined(POLARSSL_KEY_EXCHANGE__SOME__PSK_ENABLED) #if defined(POLARSSL_KEY_EXCHANGE__SOME__PSK_ENABLED)
if( ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_PSK || if( ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_PSK ||
ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_RSA_PSK || ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_RSA_PSK ||

View file

@ -2316,11 +2316,13 @@ int ssl_send_alert_message( ssl_context *ssl,
/* /*
* Handshake functions * Handshake functions
*/ */
#if !defined(POLARSSL_KEY_EXCHANGE_RSA_ENABLED) && \ #if !defined(POLARSSL_KEY_EXCHANGE_RSA_ENABLED) && \
!defined(POLARSSL_KEY_EXCHANGE_RSA_PSK_ENABLED) && \ !defined(POLARSSL_KEY_EXCHANGE_RSA_PSK_ENABLED) && \
!defined(POLARSSL_KEY_EXCHANGE_DHE_RSA_ENABLED) && \ !defined(POLARSSL_KEY_EXCHANGE_DHE_RSA_ENABLED) && \
!defined(POLARSSL_KEY_EXCHANGE_ECDHE_RSA_ENABLED) && \ !defined(POLARSSL_KEY_EXCHANGE_ECDHE_RSA_ENABLED) && \
!defined(POLARSSL_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) !defined(POLARSSL_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) && \
!defined(POLARSSL_KEY_EXCHANGE_ECDH_RSA_ENABLED) && \
!defined(POLARSSL_KEY_EXCHANGE_ECDH_ECDSA_ENABLED)
int ssl_write_certificate( ssl_context *ssl ) int ssl_write_certificate( ssl_context *ssl )
{ {
int ret = POLARSSL_ERR_SSL_FEATURE_UNAVAILABLE; int ret = POLARSSL_ERR_SSL_FEATURE_UNAVAILABLE;
@ -2649,9 +2651,13 @@ int ssl_parse_certificate( ssl_context *ssl )
return( ret ); return( ret );
} }
#endif /* !POLARSSL_KEY_EXCHANGE_RSA_ENABLED && #endif /* !POLARSSL_KEY_EXCHANGE_RSA_ENABLED
!POLARSSL_KEY_EXCHANGE_DHE_RSA_ENABLED && !POLARSSL_KEY_EXCHANGE_RSA_PSK_ENABLED
!POLARSSL_KEY_EXCHANGE_ECDHE_RSA_ENABLED */ !POLARSSL_KEY_EXCHANGE_DHE_RSA_ENABLED
!POLARSSL_KEY_EXCHANGE_ECDHE_RSA_ENABLED
!POLARSSL_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED
!POLARSSL_KEY_EXCHANGE_ECDH_RSA_ENABLED
!POLARSSL_KEY_EXCHANGE_ECDH_ECDSA_ENABLED */
int ssl_write_change_cipher_spec( ssl_context *ssl ) int ssl_write_change_cipher_spec( ssl_context *ssl )
{ {