Rebase and address review comments
Signed-off-by: Xiaofei Bai <xiaofei.bai@arm.com>
diff --git a/library/ssl_tls13_generic.c b/library/ssl_tls13_generic.c
index aeefdc7..2f4d04e 100644
--- a/library/ssl_tls13_generic.c
+++ b/library/ssl_tls13_generic.c
@@ -136,90 +136,6 @@
}
#if defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED)
-
-/*
- * mbedtls_ssl_tls13_write_sig_alg_ext( )
- *
- * enum {
- * ....
- * ecdsa_secp256r1_sha256( 0x0403 ),
- * ecdsa_secp384r1_sha384( 0x0503 ),
- * ecdsa_secp521r1_sha512( 0x0603 ),
- * ....
- * } SignatureScheme;
- *
- * struct {
- * SignatureScheme supported_signature_algorithms<2..2^16-2>;
- * } SignatureSchemeList;
- *
- * Only if we handle at least one key exchange that needs signatures.
- */
-int mbedtls_ssl_tls13_write_sig_alg_ext( mbedtls_ssl_context *ssl,
- unsigned char *buf,
- unsigned char *end,
- size_t *out_len )
-{
- unsigned char *p = buf;
- unsigned char *supported_sig_alg; /* Start of supported_signature_algorithms */
- size_t supported_sig_alg_len = 0; /* Length of supported_signature_algorithms */
-
- *out_len = 0;
-
- /* Skip the extension on the client if all allowed key exchanges
- * are PSK-based. */
-#if defined(MBEDTLS_SSL_CLI_C)
- if( ssl->conf->endpoint == MBEDTLS_SSL_IS_CLIENT &&
- !mbedtls_ssl_conf_tls13_some_ephemeral_enabled( ssl ) )
- {
- return( 0 );
- }
-#endif /* MBEDTLS_SSL_CLI_C */
-
- MBEDTLS_SSL_DEBUG_MSG( 3, ( "adding signature_algorithms extension" ) );
-
- /* Check if we have space for header and length field:
- * - extension_type (2 bytes)
- * - extension_data_length (2 bytes)
- * - supported_signature_algorithms_length (2 bytes)
- */
- MBEDTLS_SSL_CHK_BUF_PTR( p, end, 6 );
- p += 6;
-
- /*
- * Write supported_signature_algorithms
- */
- supported_sig_alg = p;
- for( const uint16_t *sig_alg = ssl->conf->tls13_sig_algs;
- *sig_alg != MBEDTLS_TLS1_3_SIG_NONE; sig_alg++ )
- {
- MBEDTLS_SSL_CHK_BUF_PTR( p, end, 2 );
- MBEDTLS_PUT_UINT16_BE( *sig_alg, p, 0 );
- p += 2;
- MBEDTLS_SSL_DEBUG_MSG( 3, ( "signature scheme [%x]", *sig_alg ) );
- }
-
- /* Length of supported_signature_algorithms */
- supported_sig_alg_len = p - supported_sig_alg;
- if( supported_sig_alg_len == 0 )
- {
- MBEDTLS_SSL_DEBUG_MSG( 1, ( "No signature algorithms defined." ) );
- return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
- }
-
- /* Write extension_type */
- MBEDTLS_PUT_UINT16_BE( MBEDTLS_TLS_EXT_SIG_ALG, buf, 0 );
- /* Write extension_data_length */
- MBEDTLS_PUT_UINT16_BE( supported_sig_alg_len + 2, buf, 2 );
- /* Write length of supported_signature_algorithms */
- MBEDTLS_PUT_UINT16_BE( supported_sig_alg_len, buf, 4 );
-
- /* Output the total length of signature algorithms extension. */
- *out_len = p - buf;
-
- ssl->handshake->extensions_present |= MBEDTLS_SSL_EXT_SIG_ALG;
- return( 0 );
-}
-
/* mbedtls_ssl_tls13_parse_sig_alg_ext()
*
* enum {
@@ -239,34 +155,37 @@
const unsigned char *end )
{
const unsigned char *p = buf;
- const uint16_t *sig_alg;
- unsigned int signature_scheme; /* store received signature algorithm scheme */
+ size_t sig_algs_len = 0;
+ uint16_t *sig_algs;
+ const unsigned char *sig_algs_end;
+ uint16_t sig_alg;
uint32_t common_idx = 0; /* iterate through received signature schemes list */
/* skip 2 bytes of signature algorithms length */
MBEDTLS_SSL_CHK_BUF_READ_PTR( p, end, 2 );
+ sig_algs_len = MBEDTLS_GET_UINT16_BE( p, 0 );
p += 2;
- memset( ssl->handshake->sig_algs, 0, sizeof( ssl->handshake->sig_algs ) );
+ sig_algs = mbedtls_calloc( MBEDTLS_SIG_ALGS_SIZE, sizeof( uint16_t ) );
+ if( sig_algs == NULL )
+ return( MBEDTLS_ERR_SSL_ALLOC_FAILED );
- while( p < end && common_idx + 1 < MBEDTLS_PK_SIGNATURE_MAX_SIZE )
+ MBEDTLS_SSL_CHK_BUF_READ_PTR( p, end, sig_algs_len );
+ sig_algs_end = p + sig_algs_len;
+ while( p < sig_algs_end && common_idx + 1 < MBEDTLS_SIG_ALGS_SIZE )
{
- MBEDTLS_SSL_CHK_BUF_READ_PTR( p, end, 2 );
- signature_scheme = MBEDTLS_GET_UINT16_BE( p, 0 );
+ MBEDTLS_SSL_CHK_BUF_READ_PTR( p, sig_algs_end, 2 );
+ sig_alg = MBEDTLS_GET_UINT16_BE( p, 0 );
p += 2;
MBEDTLS_SSL_DEBUG_MSG( 4, ( "received signature algorithm: 0x%x",
- signature_scheme ) );
+ sig_alg ) );
- for( sig_alg = ssl->conf->tls13_sig_algs;
- *sig_alg != MBEDTLS_TLS1_3_SIG_NONE; sig_alg++ )
+ if( mbedtls_ssl_sig_alg_is_offered( ssl, sig_alg ) &&
+ mbedtls_ssl_sig_alg_is_supported( ssl, sig_alg ) )
{
- if( *sig_alg == signature_scheme )
- {
- ssl->handshake->sig_algs[common_idx] = signature_scheme;
- common_idx++;
- break;
- }
+ sig_algs[common_idx] = sig_alg;
+ common_idx += 1;
}
}
/* Check that we consumed all the message. */
@@ -276,6 +195,7 @@
( "Signature algorithms extension length misaligned" ) );
MBEDTLS_SSL_PEND_FATAL_ALERT( MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR,
MBEDTLS_ERR_SSL_DECODE_ERROR );
+ mbedtls_free( sig_algs );
return( MBEDTLS_ERR_SSL_DECODE_ERROR );
}
@@ -284,11 +204,13 @@
MBEDTLS_SSL_DEBUG_MSG( 3, ( "no signature algorithm in common" ) );
MBEDTLS_SSL_PEND_FATAL_ALERT( MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE,
MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE );
+ mbedtls_free( sig_algs );
return( MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE );
}
- ssl->handshake->sig_algs[common_idx] = MBEDTLS_TLS1_3_SIG_NONE;
-
+ sig_algs[common_idx] = MBEDTLS_TLS1_3_SIG_NONE;
+ ssl->handshake->sig_algs = sig_algs;
+ ssl->handshake->sig_algs_heap_allocated = 1;
return( 0 );
}