Fix bugs in ECDHE_PSK key exchange

This commit is contained in:
Manuel Pégourié-Gonnard 2013-10-14 12:00:45 +02:00
parent 225d6aa786
commit b59d699a65
2 changed files with 34 additions and 56 deletions

View file

@ -1908,6 +1908,7 @@ static int ssl_write_client_key_exchange( ssl_context *ssl )
if( ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_ECDHE_PSK )
{
unsigned char *p = ssl->handshake->premaster;
size_t zlen;
/*
* ECDHE_PSK key exchange: RFC 5489, section 2
@ -1922,14 +1923,14 @@ static int ssl_write_client_key_exchange( ssl_context *ssl )
return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
i = 4;
n = ssl->psk_identity_len;
ssl->out_msg[4] = (unsigned char)( n >> 8 );
ssl->out_msg[5] = (unsigned char)( n );
ssl->out_msg[i++] = (unsigned char)( ssl->psk_identity_len >> 8 );
ssl->out_msg[i++] = (unsigned char)( ssl->psk_identity_len );
memcpy( ssl->out_msg + 6, ssl->psk_identity, ssl->psk_identity_len );
memcpy( ssl->out_msg + i, ssl->psk_identity, ssl->psk_identity_len );
i += ssl->psk_identity_len;
ret = ecdh_make_public( &ssl->handshake->ecdh_ctx, &n,
&ssl->out_msg[8 + ssl->psk_identity_len], 512,
&ssl->out_msg[i], 1000,
ssl->f_rng, ssl->p_rng );
if( ret != 0 )
{
@ -1937,9 +1938,6 @@ static int ssl_write_client_key_exchange( ssl_context *ssl )
return( ret );
}
ssl->out_msg[6 + ssl->psk_identity_len] = (unsigned char)( n >> 8 );
ssl->out_msg[7 + ssl->psk_identity_len] = (unsigned char)( n );
SSL_DEBUG_ECP( 3, "ECDH: Q", &ssl->handshake->ecdh_ctx.Q );
/*
@ -1949,7 +1947,7 @@ static int ssl_write_client_key_exchange( ssl_context *ssl )
* };
* with "other_secret" containing Z from ECDH
*/
if( ( ret = ecdh_calc_secret( &ssl->handshake->ecdh_ctx, &n,
if( ( ret = ecdh_calc_secret( &ssl->handshake->ecdh_ctx, &zlen,
p + 2, POLARSSL_MPI_MAX_SIZE,
ssl->f_rng, ssl->p_rng ) ) != 0 )
{
@ -1957,9 +1955,9 @@ static int ssl_write_client_key_exchange( ssl_context *ssl )
return( ret );
}
*(p++) = (unsigned char)( n >> 8 );
*(p++) = (unsigned char)( n );
p += n;
*(p++) = (unsigned char)( zlen >> 8 );
*(p++) = (unsigned char)( zlen );
p += zlen;
SSL_DEBUG_MPI( 3, "ECDH: z", &ssl->handshake->ecdh_ctx.z );
@ -1968,8 +1966,7 @@ static int ssl_write_client_key_exchange( ssl_context *ssl )
memcpy( p, ssl->psk, ssl->psk_len );
p += ssl->psk_len;
ssl->handshake->pmslen = 4 + n + ssl->psk_len;
n = ssl->handshake->pmslen;
ssl->handshake->pmslen = p - ssl->handshake->premaster;
}
else
#endif /* POLARSSL_KEY_EXCHANGE_ECDHE_PSK_ENABLED */

View file

@ -2287,41 +2287,6 @@ static int ssl_parse_client_dh_public( ssl_context *ssl, unsigned char **p,
#endif /* POLARSSL_KEY_EXCHANGE_DHE_RSA_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)
static int ssl_parse_client_ecdh_public( ssl_context *ssl )
{
int ret;
size_t n;
/*
* Receive client public key and calculate premaster
*/
n = ssl->in_msg[3];
if( n < 1 || n > mpi_size( &ssl->handshake->ecdh_ctx.grp.P ) * 2 + 2 ||
n + 4 != ssl->in_hslen )
{
SSL_DEBUG_MSG( 1, ( "bad client key exchange message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE );
}
if( ( ret = ecdh_read_public( &ssl->handshake->ecdh_ctx,
ssl->in_msg + 4, n ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ecdh_read_public", ret );
return( POLARSSL_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE_RP );
}
SSL_DEBUG_ECP( 3, "ECDH: Qp ", &ssl->handshake->ecdh_ctx.Qp );
return( ret );
}
#endif /* POLARSSL_KEY_EXCHANGE_ECDHE_RSA_ENABLED ||
POLARSSL_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED ||
POLARSSL_KEY_EXCHANGE_ECDHE_PSK_ENABLED */
#if defined(POLARSSL_KEY_EXCHANGE_RSA_ENABLED)
static int ssl_parse_encrypted_pms_secret( ssl_context *ssl )
{
@ -2522,12 +2487,24 @@ static int ssl_parse_client_key_exchange( ssl_context *ssl )
if( ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_ECDHE_RSA ||
ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_ECDHE_ECDSA )
{
if( ( ret = ssl_parse_client_ecdh_public( ssl ) ) != 0 )
size_t n = ssl->in_msg[3];
if( n < 1 || n > mpi_size( &ssl->handshake->ecdh_ctx.grp.P ) * 2 + 2 ||
n + 4 != ssl->in_hslen )
{
SSL_DEBUG_RET( 1, ( "ssl_parse_client_ecdh_public" ), ret );
return( ret );
SSL_DEBUG_MSG( 1, ( "bad client key exchange message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE );
}
if( ( ret = ecdh_read_public( &ssl->handshake->ecdh_ctx,
ssl->in_msg + 4, n ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ecdh_read_public", ret );
return( POLARSSL_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE_RP );
}
SSL_DEBUG_ECP( 3, "ECDH: Qp ", &ssl->handshake->ecdh_ctx.Qp );
if( ( ret = ecdh_calc_secret( &ssl->handshake->ecdh_ctx,
&ssl->handshake->pmslen,
ssl->handshake->premaster,
@ -2629,12 +2606,16 @@ static int ssl_parse_client_key_exchange( ssl_context *ssl )
SSL_DEBUG_RET( 1, ( "ssl_parse_client_psk_identity" ), ret );
return( ret );
}
if( ( ret = ssl_parse_client_ecdh_public( ssl ) ) != 0 )
if( ( ret = ecdh_read_public( &ssl->handshake->ecdh_ctx,
p, end - p ) ) != 0 )
{
SSL_DEBUG_RET( 1, ( "ssl_parse_client_ecdh_public" ), ret );
return( ret );
SSL_DEBUG_RET( 1, "ecdh_read_public", ret );
return( POLARSSL_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE_RP );
}
SSL_DEBUG_ECP( 3, "ECDH: Qp ", &ssl->handshake->ecdh_ctx.Qp );
// Set up the premaster secret
//
p = ssl->handshake->premaster;
@ -2668,7 +2649,7 @@ static int ssl_parse_client_key_exchange( ssl_context *ssl )
{
if( ( ret = ssl_parse_encrypted_pms_secret( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, ( "ssl_parse_client_ecdh_public" ), ret );
SSL_DEBUG_RET( 1, ( "ssl_parse_parse_ecrypted_pms_secret" ), ret );
return( ret );
}
}