Refactor ciphersuite selection for version > 2

This commit is contained in:
Manuel Pégourié-Gonnard 2013-11-30 17:46:04 +01:00
parent a8239a4490
commit 59b81d73b4

View file

@ -974,6 +974,59 @@ static int ssl_pick_cert( ssl_context *ssl,
}
#endif /* POLARSSL_X509_CRT_PARSE_C */
/*
* Check if a given ciphersuite is suitable for use with our config/keys/etc
* Sets ciphersuite_info only if the suite matches.
*/
static int ssl_ciphersuite_match( ssl_context *ssl, int suite_id,
const ssl_ciphersuite_t **ciphersuite_info )
{
const ssl_ciphersuite_t *suite_info;
suite_info = ssl_ciphersuite_from_id( suite_id );
if( suite_info == NULL )
{
SSL_DEBUG_MSG( 1, ( "ciphersuite info for %04x not found", suite_id ) );
return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
}
if( suite_info->min_minor_ver > ssl->minor_ver ||
suite_info->max_minor_ver < ssl->minor_ver )
return( 0 );
#if defined(POLARSSL_ECDH_C) || defined(POLARSSL_ECDSA_C)
if( ssl_ciphersuite_uses_ec( suite_info ) &&
( ssl->handshake->curves == NULL ||
ssl->handshake->curves[0] == NULL ) )
return( 0 );
#endif
#if defined(POLARSSL_KEY_EXCHANGE__SOME__PSK_ENABLED)
/* If the ciphersuite requires a pre-shared key and we don't
* have one, skip it now rather than failing later */
if( ssl_ciphersuite_uses_psk( suite_info ) &&
ssl->f_psk == NULL &&
( ssl->psk == NULL || ssl->psk_identity == NULL ||
ssl->psk_identity_len == 0 || ssl->psk_len == 0 ) )
return( 0 );
#endif
#if defined(POLARSSL_X509_CRT_PARSE_C)
/*
* Final check: if ciphersuite requires us to have a
* certificate/key of a particular type:
* - select the appropriate certificate if we have one, or
* - try the next ciphersuite if we don't
* This must be done last since we modify the key_cert list.
*/
if( ssl_pick_cert( ssl, suite_info ) != 0 )
return( 0 );
#endif
*ciphersuite_info = suite_info;
return( 0 );
}
static int ssl_parse_client_hello( ssl_context *ssl )
{
int ret;
@ -1372,6 +1425,7 @@ static int ssl_parse_client_hello( ssl_context *ssl )
* and certificate from the SNI callback triggered by the SNI extension.)
*/
ciphersuites = ssl->ciphersuite_list[ssl->minor_ver];
ciphersuite_info = NULL;
for( i = 0; ciphersuites[i] != 0; i++ )
{
for( j = 0, p = buf + 41 + sess_len; j < ciph_len;
@ -1380,49 +1434,12 @@ static int ssl_parse_client_hello( ssl_context *ssl )
if( p[0] == ( ( ciphersuites[i] >> 8 ) & 0xFF ) &&
p[1] == ( ( ciphersuites[i] ) & 0xFF ) )
{
ciphersuite_info = ssl_ciphersuite_from_id( ciphersuites[i] );
if( ( ret = ssl_ciphersuite_match( ssl, ciphersuites[i],
&ciphersuite_info ) ) != 0 )
return( ret );
if( ciphersuite_info == NULL )
{
SSL_DEBUG_MSG( 1, ( "ciphersuite info for %04x not found",
ciphersuites[i] ) );
return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
}
if( ciphersuite_info->min_minor_ver > ssl->minor_ver ||
ciphersuite_info->max_minor_ver < ssl->minor_ver )
continue;
#if defined(POLARSSL_ECDH_C) || defined(POLARSSL_ECDSA_C)
if( ssl_ciphersuite_uses_ec( ciphersuite_info ) &&
( ssl->handshake->curves == NULL ||
ssl->handshake->curves[0] == NULL ) )
continue;
#endif
#if defined(POLARSSL_KEY_EXCHANGE__SOME__PSK_ENABLED)
/* If the ciphersuite requires a pre-shared key and we don't
* have one, skip it now rather than failing later */
if( ssl_ciphersuite_uses_psk( ciphersuite_info ) &&
ssl->f_psk == NULL &&
( ssl->psk == NULL || ssl->psk_identity == NULL ||
ssl->psk_identity_len == 0 || ssl->psk_len == 0 ) )
continue;
#endif
#if defined(POLARSSL_X509_CRT_PARSE_C)
/*
* Final check: if ciphersuite requires us to have a
* certificate/key of a particular type:
* - select the appropriate certificate if we have one, or
* - try the next ciphersuite if we don't
* This must be done last since we modify the key_cert list.
*/
if( ssl_pick_cert( ssl, ciphersuite_info ) != 0 )
continue;
#endif
goto have_ciphersuite;
if( ciphersuite_info != NULL )
goto have_ciphersuite;
}
}
}