diff options
Diffstat (limited to 'thirdparty/mbedtls/library/ssl_tls.c')
| -rw-r--r-- | thirdparty/mbedtls/library/ssl_tls.c | 493 |
1 files changed, 273 insertions, 220 deletions
diff --git a/thirdparty/mbedtls/library/ssl_tls.c b/thirdparty/mbedtls/library/ssl_tls.c index 236e52d767..e8e0cd854b 100644 --- a/thirdparty/mbedtls/library/ssl_tls.c +++ b/thirdparty/mbedtls/library/ssl_tls.c @@ -46,6 +46,7 @@ #include "mbedtls/debug.h" #include "mbedtls/ssl.h" #include "mbedtls/ssl_internal.h" +#include "mbedtls/platform_util.h" #include <string.h> @@ -53,11 +54,6 @@ #include "mbedtls/oid.h" #endif -/* Implementation that should never be optimized out by the compiler */ -static void mbedtls_zeroize( void *v, size_t n ) { - volatile unsigned char *p = v; while( n-- ) *p++ = 0; -} - /* Length of the "epoch" field in the record header */ static inline size_t ssl_ep_len( const mbedtls_ssl_context *ssl ) { @@ -269,8 +265,8 @@ exit: mbedtls_md5_free( &md5 ); mbedtls_sha1_free( &sha1 ); - mbedtls_zeroize( padding, sizeof( padding ) ); - mbedtls_zeroize( sha1sum, sizeof( sha1sum ) ); + mbedtls_platform_zeroize( padding, sizeof( padding ) ); + mbedtls_platform_zeroize( sha1sum, sizeof( sha1sum ) ); return( ret ); } @@ -367,8 +363,8 @@ static int tls1_prf( const unsigned char *secret, size_t slen, mbedtls_md_free( &md_ctx ); - mbedtls_zeroize( tmp, sizeof( tmp ) ); - mbedtls_zeroize( h_i, sizeof( h_i ) ); + mbedtls_platform_zeroize( tmp, sizeof( tmp ) ); + mbedtls_platform_zeroize( h_i, sizeof( h_i ) ); return( 0 ); } @@ -432,8 +428,8 @@ static int tls_prf_generic( mbedtls_md_type_t md_type, mbedtls_md_free( &md_ctx ); - mbedtls_zeroize( tmp, sizeof( tmp ) ); - mbedtls_zeroize( h_i, sizeof( h_i ) ); + mbedtls_platform_zeroize( tmp, sizeof( tmp ) ); + mbedtls_platform_zeroize( h_i, sizeof( h_i ) ); return( 0 ); } @@ -642,7 +638,8 @@ int mbedtls_ssl_derive_keys( mbedtls_ssl_context *ssl ) return( ret ); } - mbedtls_zeroize( handshake->premaster, sizeof(handshake->premaster) ); + mbedtls_platform_zeroize( handshake->premaster, + sizeof(handshake->premaster) ); } else MBEDTLS_SSL_DEBUG_MSG( 3, ( "no premaster (session resumed)" ) ); @@ -653,7 +650,7 @@ int mbedtls_ssl_derive_keys( mbedtls_ssl_context *ssl ) memcpy( tmp, handshake->randbytes, 64 ); memcpy( handshake->randbytes, tmp + 32, 32 ); memcpy( handshake->randbytes + 32, tmp, 32 ); - mbedtls_zeroize( tmp, sizeof( tmp ) ); + mbedtls_platform_zeroize( tmp, sizeof( tmp ) ); /* * SSLv3: @@ -681,7 +678,8 @@ int mbedtls_ssl_derive_keys( mbedtls_ssl_context *ssl ) MBEDTLS_SSL_DEBUG_BUF( 4, "random bytes", handshake->randbytes, 64 ); MBEDTLS_SSL_DEBUG_BUF( 4, "key block", keyblk, 256 ); - mbedtls_zeroize( handshake->randbytes, sizeof( handshake->randbytes ) ); + mbedtls_platform_zeroize( handshake->randbytes, + sizeof( handshake->randbytes ) ); /* * Determine the appropriate key, IV and MAC length. @@ -855,8 +853,13 @@ int mbedtls_ssl_derive_keys( mbedtls_ssl_context *ssl ) defined(MBEDTLS_SSL_PROTO_TLS1_2) if( ssl->minor_ver >= MBEDTLS_SSL_MINOR_VERSION_1 ) { - mbedtls_md_hmac_starts( &transform->md_ctx_enc, mac_enc, mac_key_len ); - mbedtls_md_hmac_starts( &transform->md_ctx_dec, mac_dec, mac_key_len ); + /* For HMAC-based ciphersuites, initialize the HMAC transforms. + For AEAD-based ciphersuites, there is nothing to do here. */ + if( mac_key_len != 0 ) + { + mbedtls_md_hmac_starts( &transform->md_ctx_enc, mac_enc, mac_key_len ); + mbedtls_md_hmac_starts( &transform->md_ctx_dec, mac_dec, mac_key_len ); + } } else #endif @@ -943,7 +946,7 @@ int mbedtls_ssl_derive_keys( mbedtls_ssl_context *ssl ) } #endif /* MBEDTLS_CIPHER_MODE_CBC */ - mbedtls_zeroize( keyblk, sizeof( keyblk ) ); + mbedtls_platform_zeroize( keyblk, sizeof( keyblk ) ); #if defined(MBEDTLS_ZLIB_SUPPORT) // Initialize compression @@ -1269,7 +1272,7 @@ static void ssl_mac( mbedtls_md_context_t *md_ctx, #if defined(MBEDTLS_ARC4_C) || defined(MBEDTLS_CIPHER_NULL_CIPHER) || \ ( defined(MBEDTLS_CIPHER_MODE_CBC) && \ - ( defined(MBEDTLS_AES_C) || defined(MBEDTLS_CAMELLIA_C) ) ) + ( defined(MBEDTLS_AES_C) || defined(MBEDTLS_CAMELLIA_C) || defined(MBEDTLS_ARIA_C)) ) #define SSL_SOME_MODES_USE_MAC #endif @@ -1470,7 +1473,7 @@ static int ssl_encrypt_buf( mbedtls_ssl_context *ssl ) else #endif /* MBEDTLS_GCM_C || MBEDTLS_CCM_C */ #if defined(MBEDTLS_CIPHER_MODE_CBC) && \ - ( defined(MBEDTLS_AES_C) || defined(MBEDTLS_CAMELLIA_C) ) + ( defined(MBEDTLS_AES_C) || defined(MBEDTLS_CAMELLIA_C) || defined(MBEDTLS_ARIA_C) ) if( mode == MBEDTLS_MODE_CBC ) { int ret; @@ -1586,7 +1589,7 @@ static int ssl_encrypt_buf( mbedtls_ssl_context *ssl ) } else #endif /* MBEDTLS_CIPHER_MODE_CBC && - ( MBEDTLS_AES_C || MBEDTLS_CAMELLIA_C ) */ + ( MBEDTLS_AES_C || MBEDTLS_CAMELLIA_C || MBEDTLS_ARIA_C ) */ { MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) ); return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); @@ -1730,7 +1733,7 @@ static int ssl_decrypt_buf( mbedtls_ssl_context *ssl ) else #endif /* MBEDTLS_GCM_C || MBEDTLS_CCM_C */ #if defined(MBEDTLS_CIPHER_MODE_CBC) && \ - ( defined(MBEDTLS_AES_C) || defined(MBEDTLS_CAMELLIA_C) ) + ( defined(MBEDTLS_AES_C) || defined(MBEDTLS_CAMELLIA_C) || defined(MBEDTLS_ARIA_C) ) if( mode == MBEDTLS_MODE_CBC ) { /* @@ -1942,7 +1945,7 @@ static int ssl_decrypt_buf( mbedtls_ssl_context *ssl ) } else #endif /* MBEDTLS_CIPHER_MODE_CBC && - ( MBEDTLS_AES_C || MBEDTLS_CAMELLIA_C ) */ + ( MBEDTLS_AES_C || MBEDTLS_CAMELLIA_C || MBEDTLS_ARIA_C ) */ { MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) ); return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); @@ -2103,6 +2106,7 @@ static int ssl_compress_buf( mbedtls_ssl_context *ssl ) { int ret; unsigned char *msg_post = ssl->out_msg; + ptrdiff_t bytes_written = ssl->out_msg - ssl->out_buf; size_t len_pre = ssl->out_msglen; unsigned char *msg_pre = ssl->compress_buf; @@ -2122,7 +2126,7 @@ static int ssl_compress_buf( mbedtls_ssl_context *ssl ) ssl->transform_out->ctx_deflate.next_in = msg_pre; ssl->transform_out->ctx_deflate.avail_in = len_pre; ssl->transform_out->ctx_deflate.next_out = msg_post; - ssl->transform_out->ctx_deflate.avail_out = MBEDTLS_SSL_BUFFER_LEN; + ssl->transform_out->ctx_deflate.avail_out = MBEDTLS_SSL_BUFFER_LEN - bytes_written; ret = deflate( &ssl->transform_out->ctx_deflate, Z_SYNC_FLUSH ); if( ret != Z_OK ) @@ -2132,7 +2136,7 @@ static int ssl_compress_buf( mbedtls_ssl_context *ssl ) } ssl->out_msglen = MBEDTLS_SSL_BUFFER_LEN - - ssl->transform_out->ctx_deflate.avail_out; + ssl->transform_out->ctx_deflate.avail_out - bytes_written; MBEDTLS_SSL_DEBUG_MSG( 3, ( "after compression: msglen = %d, ", ssl->out_msglen ) ); @@ -2149,6 +2153,7 @@ static int ssl_decompress_buf( mbedtls_ssl_context *ssl ) { int ret; unsigned char *msg_post = ssl->in_msg; + ptrdiff_t header_bytes = ssl->in_msg - ssl->in_buf; size_t len_pre = ssl->in_msglen; unsigned char *msg_pre = ssl->compress_buf; @@ -2168,7 +2173,8 @@ static int ssl_decompress_buf( mbedtls_ssl_context *ssl ) ssl->transform_in->ctx_inflate.next_in = msg_pre; ssl->transform_in->ctx_inflate.avail_in = len_pre; ssl->transform_in->ctx_inflate.next_out = msg_post; - ssl->transform_in->ctx_inflate.avail_out = MBEDTLS_SSL_MAX_CONTENT_LEN; + ssl->transform_in->ctx_inflate.avail_out = MBEDTLS_SSL_BUFFER_LEN - + header_bytes; ret = inflate( &ssl->transform_in->ctx_inflate, Z_SYNC_FLUSH ); if( ret != Z_OK ) @@ -2177,8 +2183,8 @@ static int ssl_decompress_buf( mbedtls_ssl_context *ssl ) return( MBEDTLS_ERR_SSL_COMPRESSION_FAILED ); } - ssl->in_msglen = MBEDTLS_SSL_MAX_CONTENT_LEN - - ssl->transform_in->ctx_inflate.avail_out; + ssl->in_msglen = MBEDTLS_SSL_BUFFER_LEN - + ssl->transform_in->ctx_inflate.avail_out - header_bytes; MBEDTLS_SSL_DEBUG_MSG( 3, ( "after decompression: msglen = %d, ", ssl->in_msglen ) ); @@ -2332,7 +2338,10 @@ int mbedtls_ssl_fetch_input( mbedtls_ssl_context *ssl, size_t nb_want ) * that will end up being dropped. */ if( ssl_check_timer( ssl ) != 0 ) + { + MBEDTLS_SSL_DEBUG_MSG( 2, ( "timer has expired" ) ); ret = MBEDTLS_ERR_SSL_TIMEOUT; + } else { len = MBEDTLS_SSL_BUFFER_LEN - ( ssl->in_hdr - ssl->in_buf ); @@ -2434,6 +2443,14 @@ int mbedtls_ssl_fetch_input( mbedtls_ssl_context *ssl, size_t nb_want ) if( ret < 0 ) return( ret ); + if ( (size_t)ret > len || ( INT_MAX > SIZE_MAX && ret > SIZE_MAX ) ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, + ( "f_recv returned %d bytes but only %lu were requested", + ret, (unsigned long)len ) ); + return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); + } + ssl->in_left += ret; } } @@ -2481,6 +2498,14 @@ int mbedtls_ssl_flush_output( mbedtls_ssl_context *ssl ) if( ret <= 0 ) return( ret ); + if( (size_t)ret > ssl->out_left || ( INT_MAX > SIZE_MAX && ret > SIZE_MAX ) ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, + ( "f_send returned %d bytes but only %lu bytes were sent", + ret, (unsigned long)ssl->out_left ) ); + return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); + } + ssl->out_left -= ret; } @@ -3064,7 +3089,7 @@ static int ssl_reassemble_dtls_handshake( mbedtls_ssl_context *ssl ) if( ssl_bitmask_check( bitmask, msg_len ) != 0 ) { MBEDTLS_SSL_DEBUG_MSG( 2, ( "message is not complete yet" ) ); - return( MBEDTLS_ERR_SSL_WANT_READ ); + return( MBEDTLS_ERR_SSL_CONTINUE_PROCESSING ); } MBEDTLS_SSL_DEBUG_MSG( 2, ( "handshake message completed" ) ); @@ -3141,9 +3166,11 @@ int mbedtls_ssl_prepare_handshake_record( mbedtls_ssl_context *ssl ) int ret; unsigned int recv_msg_seq = ( ssl->in_msg[4] << 8 ) | ssl->in_msg[5]; - /* ssl->handshake is NULL when receiving ClientHello for renego */ if( ssl->handshake != NULL && - recv_msg_seq != ssl->handshake->in_msg_seq ) + ( ( ssl->state != MBEDTLS_SSL_HANDSHAKE_OVER && + recv_msg_seq != ssl->handshake->in_msg_seq ) || + ( ssl->state == MBEDTLS_SSL_HANDSHAKE_OVER && + ssl->in_msg[0] != MBEDTLS_SSL_HS_CLIENT_HELLO ) ) ) { /* Retransmit only on last message from previous flight, to avoid * too many retransmissions. @@ -3170,7 +3197,7 @@ int mbedtls_ssl_prepare_handshake_record( mbedtls_ssl_context *ssl ) ssl->handshake->in_msg_seq ) ); } - return( MBEDTLS_ERR_SSL_WANT_READ ); + return( MBEDTLS_ERR_SSL_CONTINUE_PROCESSING ); } /* Wait until message completion to increment in_msg_seq */ @@ -3573,81 +3600,23 @@ static int ssl_parse_record_header( mbedtls_ssl_context *ssl ) return( MBEDTLS_ERR_SSL_INVALID_RECORD ); } - /* Check length against bounds of the current transform and version */ - if( ssl->transform_in == NULL ) - { - if( ssl->in_msglen < 1 || - ssl->in_msglen > MBEDTLS_SSL_MAX_CONTENT_LEN ) - { - MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad message length" ) ); - return( MBEDTLS_ERR_SSL_INVALID_RECORD ); - } - } - else - { - if( ssl->in_msglen < ssl->transform_in->minlen ) - { - MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad message length" ) ); - return( MBEDTLS_ERR_SSL_INVALID_RECORD ); - } - -#if defined(MBEDTLS_SSL_PROTO_SSL3) - if( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 && - ssl->in_msglen > ssl->transform_in->minlen + MBEDTLS_SSL_MAX_CONTENT_LEN ) - { - MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad message length" ) ); - return( MBEDTLS_ERR_SSL_INVALID_RECORD ); - } -#endif -#if defined(MBEDTLS_SSL_PROTO_TLS1) || defined(MBEDTLS_SSL_PROTO_TLS1_1) || \ - defined(MBEDTLS_SSL_PROTO_TLS1_2) - /* - * TLS encrypted messages can have up to 256 bytes of padding - */ - if( ssl->minor_ver >= MBEDTLS_SSL_MINOR_VERSION_1 && - ssl->in_msglen > ssl->transform_in->minlen + - MBEDTLS_SSL_MAX_CONTENT_LEN + 256 ) - { - MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad message length" ) ); - return( MBEDTLS_ERR_SSL_INVALID_RECORD ); - } -#endif - } - /* - * DTLS-related tests done last, because most of them may result in - * silently dropping the record (but not the whole datagram), and we only - * want to consider that after ensuring that the "basic" fields (type, - * version, length) are sane. + * DTLS-related tests. + * Check epoch before checking length constraint because + * the latter varies with the epoch. E.g., if a ChangeCipherSpec + * message gets duplicated before the corresponding Finished message, + * the second ChangeCipherSpec should be discarded because it belongs + * to an old epoch, but not because its length is shorter than + * the minimum record length for packets using the new record transform. + * Note that these two kinds of failures are handled differently, + * as an unexpected record is silently skipped but an invalid + * record leads to the entire datagram being dropped. */ #if defined(MBEDTLS_SSL_PROTO_DTLS) if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM ) { unsigned int rec_epoch = ( ssl->in_ctr[0] << 8 ) | ssl->in_ctr[1]; - /* Drop unexpected ChangeCipherSpec messages */ - if( ssl->in_msgtype == MBEDTLS_SSL_MSG_CHANGE_CIPHER_SPEC && - ssl->state != MBEDTLS_SSL_CLIENT_CHANGE_CIPHER_SPEC && - ssl->state != MBEDTLS_SSL_SERVER_CHANGE_CIPHER_SPEC ) - { - MBEDTLS_SSL_DEBUG_MSG( 1, ( "dropping unexpected ChangeCipherSpec" ) ); - return( MBEDTLS_ERR_SSL_UNEXPECTED_RECORD ); - } - - /* Drop unexpected ApplicationData records, - * except at the beginning of renegotiations */ - if( ssl->in_msgtype == MBEDTLS_SSL_MSG_APPLICATION_DATA && - ssl->state != MBEDTLS_SSL_HANDSHAKE_OVER -#if defined(MBEDTLS_SSL_RENEGOTIATION) - && ! ( ssl->renego_status == MBEDTLS_SSL_RENEGOTIATION_IN_PROGRESS && - ssl->state == MBEDTLS_SSL_SERVER_HELLO ) -#endif - ) - { - MBEDTLS_SSL_DEBUG_MSG( 1, ( "dropping unexpected ApplicationData" ) ); - return( MBEDTLS_ERR_SSL_UNEXPECTED_RECORD ); - } - /* Check epoch (and sequence number) with DTLS */ if( rec_epoch != ssl->in_epoch ) { @@ -3687,9 +3656,74 @@ static int ssl_parse_record_header( mbedtls_ssl_context *ssl ) return( MBEDTLS_ERR_SSL_UNEXPECTED_RECORD ); } #endif + + /* Drop unexpected ChangeCipherSpec messages */ + if( ssl->in_msgtype == MBEDTLS_SSL_MSG_CHANGE_CIPHER_SPEC && + ssl->state != MBEDTLS_SSL_CLIENT_CHANGE_CIPHER_SPEC && + ssl->state != MBEDTLS_SSL_SERVER_CHANGE_CIPHER_SPEC ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "dropping unexpected ChangeCipherSpec" ) ); + return( MBEDTLS_ERR_SSL_UNEXPECTED_RECORD ); + } + + /* Drop unexpected ApplicationData records, + * except at the beginning of renegotiations */ + if( ssl->in_msgtype == MBEDTLS_SSL_MSG_APPLICATION_DATA && + ssl->state != MBEDTLS_SSL_HANDSHAKE_OVER +#if defined(MBEDTLS_SSL_RENEGOTIATION) + && ! ( ssl->renego_status == MBEDTLS_SSL_RENEGOTIATION_IN_PROGRESS && + ssl->state == MBEDTLS_SSL_SERVER_HELLO ) +#endif + ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "dropping unexpected ApplicationData" ) ); + return( MBEDTLS_ERR_SSL_UNEXPECTED_RECORD ); + } } #endif /* MBEDTLS_SSL_PROTO_DTLS */ + + /* Check length against bounds of the current transform and version */ + if( ssl->transform_in == NULL ) + { + if( ssl->in_msglen < 1 || + ssl->in_msglen > MBEDTLS_SSL_MAX_CONTENT_LEN ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad message length" ) ); + return( MBEDTLS_ERR_SSL_INVALID_RECORD ); + } + } + else + { + if( ssl->in_msglen < ssl->transform_in->minlen ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad message length" ) ); + return( MBEDTLS_ERR_SSL_INVALID_RECORD ); + } + +#if defined(MBEDTLS_SSL_PROTO_SSL3) + if( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 && + ssl->in_msglen > ssl->transform_in->minlen + MBEDTLS_SSL_MAX_CONTENT_LEN ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad message length" ) ); + return( MBEDTLS_ERR_SSL_INVALID_RECORD ); + } +#endif +#if defined(MBEDTLS_SSL_PROTO_TLS1) || defined(MBEDTLS_SSL_PROTO_TLS1_1) || \ + defined(MBEDTLS_SSL_PROTO_TLS1_2) + /* + * TLS encrypted messages can have up to 256 bytes of padding + */ + if( ssl->minor_ver >= MBEDTLS_SSL_MINOR_VERSION_1 && + ssl->in_msglen > ssl->transform_in->minlen + + MBEDTLS_SSL_MAX_CONTENT_LEN + 256 ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad message length" ) ); + return( MBEDTLS_ERR_SSL_INVALID_RECORD ); + } +#endif + } + return( 0 ); } @@ -3778,7 +3812,10 @@ int mbedtls_ssl_read_record( mbedtls_ssl_context *ssl ) { do { - if( ( ret = mbedtls_ssl_read_record_layer( ssl ) ) != 0 ) + do ret = mbedtls_ssl_read_record_layer( ssl ); + while( ret == MBEDTLS_ERR_SSL_CONTINUE_PROCESSING ); + + if( ret != 0 ) { MBEDTLS_SSL_DEBUG_RET( 1, ( "mbedtls_ssl_read_record_layer" ), ret ); return( ret ); @@ -3786,11 +3823,12 @@ int mbedtls_ssl_read_record( mbedtls_ssl_context *ssl ) ret = mbedtls_ssl_handle_message_type( ssl ); - } while( MBEDTLS_ERR_SSL_NON_FATAL == ret ); + } while( MBEDTLS_ERR_SSL_NON_FATAL == ret || + MBEDTLS_ERR_SSL_CONTINUE_PROCESSING == ret ); if( 0 != ret ) { - MBEDTLS_SSL_DEBUG_RET( 1, ( "mbedtls_ssl_read_record_layer" ), ret ); + MBEDTLS_SSL_DEBUG_RET( 1, ( "mbedtls_ssl_handle_message_type" ), ret ); return( ret ); } @@ -3828,11 +3866,6 @@ int mbedtls_ssl_read_record_layer( mbedtls_ssl_context *ssl ) * (2) Alert messages: * Consume whole record content, in_msglen = 0. * - * NOTE: This needs to be fixed, since like for - * handshake messages it is allowed to have - * multiple alerts witin a single record. - * Internal reference IOTSSL-1321. - * * (3) Change cipher spec: * Consume whole record content, in_msglen = 0. * @@ -3860,12 +3893,12 @@ int mbedtls_ssl_read_record_layer( mbedtls_ssl_context *ssl ) */ /* Notes: - * (1) in_hslen is *NOT* necessarily the size of the + * (1) in_hslen is not necessarily the size of the * current handshake content: If DTLS handshake * fragmentation is used, that's the fragment * size instead. Using the total handshake message - * size here is FAULTY and should be changed at - * some point. Internal reference IOTSSL-1414. + * size here is faulty and should be changed at + * some point. * (2) While it doesn't seem to cause problems, one * has to be very careful not to assume that in_hslen * is always <= in_msglen in a sensible communication. @@ -3916,12 +3949,6 @@ int mbedtls_ssl_read_record_layer( mbedtls_ssl_context *ssl ) return( 0 ); } - /* Need to fetch a new record */ - -#if defined(MBEDTLS_SSL_PROTO_DTLS) -read_record_header: -#endif - /* Current record either fully processed or to be discarded. */ if( ( ret = mbedtls_ssl_fetch_input( ssl, mbedtls_ssl_hdr_len( ssl ) ) ) != 0 ) @@ -3956,7 +3983,7 @@ read_record_header: } /* Get next record */ - goto read_record_header; + return( MBEDTLS_ERR_SSL_CONTINUE_PROCESSING ); } #endif return( ret ); @@ -3975,7 +4002,13 @@ read_record_header: /* Done reading this record, get ready for the next one */ #if defined(MBEDTLS_SSL_PROTO_DTLS) if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM ) + { ssl->next_record_offset = ssl->in_msglen + mbedtls_ssl_hdr_len( ssl ); + if( ssl->next_record_offset < ssl->in_left ) + { + MBEDTLS_SSL_DEBUG_MSG( 3, ( "more than one record within datagram" ) ); + } + } else #endif ssl->in_left = 0; @@ -4022,7 +4055,7 @@ read_record_header: ssl->in_left = 0; MBEDTLS_SSL_DEBUG_MSG( 1, ( "discarding invalid record (mac)" ) ); - goto read_record_header; + return( MBEDTLS_ERR_SSL_CONTINUE_PROCESSING ); } return( ret ); @@ -4043,46 +4076,6 @@ read_record_header: } } - /* - * When we sent the last flight of the handshake, we MUST respond to a - * retransmit of the peer's previous flight with a retransmit. (In - * practice, only the Finished message will make it, other messages - * including CCS use the old transform so they're dropped as invalid.) - * - * If the record we received is not a handshake message, however, it - * means the peer received our last flight so we can clean up - * handshake info. - * - * This check needs to be done before prepare_handshake() due to an edge - * case: if the client immediately requests renegotiation, this - * finishes the current handshake first, avoiding the new ClientHello - * being mistaken for an ancient message in the current handshake. - */ -#if defined(MBEDTLS_SSL_PROTO_DTLS) - if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM && - ssl->handshake != NULL && - ssl->state == MBEDTLS_SSL_HANDSHAKE_OVER ) - { - if( ssl->in_msgtype == MBEDTLS_SSL_MSG_HANDSHAKE && - ssl->in_msg[0] == MBEDTLS_SSL_HS_FINISHED ) - { - MBEDTLS_SSL_DEBUG_MSG( 2, ( "received retransmit of last flight" ) ); - - if( ( ret = mbedtls_ssl_resend( ssl ) ) != 0 ) - { - MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_resend", ret ); - return( ret ); - } - - return( MBEDTLS_ERR_SSL_WANT_READ ); - } - else - { - ssl_handshake_wrapup_free_hs_transform( ssl ); - } - } -#endif - return( 0 ); } @@ -4127,7 +4120,7 @@ int mbedtls_ssl_handle_message_type( mbedtls_ssl_context *ssl ) if( ssl->in_msg[0] == MBEDTLS_SSL_ALERT_LEVEL_WARNING && ssl->in_msg[1] == MBEDTLS_SSL_ALERT_MSG_NO_RENEGOTIATION ) { - MBEDTLS_SSL_DEBUG_MSG( 2, ( "is a SSLv3 no_cert" ) ); + MBEDTLS_SSL_DEBUG_MSG( 2, ( "is a SSLv3 no renegotiation alert" ) ); /* Will be handled when trying to parse ServerHello */ return( 0 ); } @@ -4149,6 +4142,15 @@ int mbedtls_ssl_handle_message_type( mbedtls_ssl_context *ssl ) return MBEDTLS_ERR_SSL_NON_FATAL; } +#if defined(MBEDTLS_SSL_PROTO_DTLS) + if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM && + ssl->handshake != NULL && + ssl->state == MBEDTLS_SSL_HANDSHAKE_OVER ) + { + ssl_handshake_wrapup_free_hs_transform( ssl ); + } +#endif + return( 0 ); } @@ -5026,9 +5028,9 @@ static void ssl_calc_finished_ssl( mbedtls_md5_free( &md5 ); mbedtls_sha1_free( &sha1 ); - mbedtls_zeroize( padbuf, sizeof( padbuf ) ); - mbedtls_zeroize( md5sum, sizeof( md5sum ) ); - mbedtls_zeroize( sha1sum, sizeof( sha1sum ) ); + mbedtls_platform_zeroize( padbuf, sizeof( padbuf ) ); + mbedtls_platform_zeroize( md5sum, sizeof( md5sum ) ); + mbedtls_platform_zeroize( sha1sum, sizeof( sha1sum ) ); MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= calc finished" ) ); } @@ -5087,7 +5089,7 @@ static void ssl_calc_finished_tls( mbedtls_md5_free( &md5 ); mbedtls_sha1_free( &sha1 ); - mbedtls_zeroize( padbuf, sizeof( padbuf ) ); + mbedtls_platform_zeroize( padbuf, sizeof( padbuf ) ); MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= calc finished" ) ); } @@ -5137,7 +5139,7 @@ static void ssl_calc_finished_tls_sha256( mbedtls_sha256_free( &sha256 ); - mbedtls_zeroize( padbuf, sizeof( padbuf ) ); + mbedtls_platform_zeroize( padbuf, sizeof( padbuf ) ); MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= calc finished" ) ); } @@ -5186,7 +5188,7 @@ static void ssl_calc_finished_tls_sha384( mbedtls_sha512_free( &sha512 ); - mbedtls_zeroize( padbuf, sizeof( padbuf ) ); + mbedtls_platform_zeroize( padbuf, sizeof( padbuf ) ); MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= calc finished" ) ); } @@ -6105,7 +6107,7 @@ int mbedtls_ssl_conf_psk( mbedtls_ssl_config *conf, if( conf->psk != NULL ) { - mbedtls_zeroize( conf->psk, conf->psk_len ); + mbedtls_platform_zeroize( conf->psk, conf->psk_len ); mbedtls_free( conf->psk ); conf->psk = NULL; @@ -6148,7 +6150,8 @@ int mbedtls_ssl_set_hs_psk( mbedtls_ssl_context *ssl, if( ssl->handshake->psk != NULL ) { - mbedtls_zeroize( ssl->handshake->psk, ssl->handshake->psk_len ); + mbedtls_platform_zeroize( ssl->handshake->psk, + ssl->handshake->psk_len ); mbedtls_free( ssl->handshake->psk ); ssl->handshake->psk_len = 0; } @@ -6278,7 +6281,7 @@ int mbedtls_ssl_set_hostname( mbedtls_ssl_context *ssl, const char *hostname ) if( ssl->hostname != NULL ) { - mbedtls_zeroize( ssl->hostname, strlen( ssl->hostname ) ); + mbedtls_platform_zeroize( ssl->hostname, strlen( ssl->hostname ) ); mbedtls_free( ssl->hostname ); } @@ -6485,6 +6488,61 @@ size_t mbedtls_ssl_get_bytes_avail( const mbedtls_ssl_context *ssl ) return( ssl->in_offt == NULL ? 0 : ssl->in_msglen ); } +int mbedtls_ssl_check_pending( const mbedtls_ssl_context *ssl ) +{ + /* + * Case A: We're currently holding back + * a message for further processing. + */ + + if( ssl->keep_current_message == 1 ) + { + MBEDTLS_SSL_DEBUG_MSG( 3, ( "ssl_check_pending: record held back for processing" ) ); + return( 1 ); + } + + /* + * Case B: Further records are pending in the current datagram. + */ + +#if defined(MBEDTLS_SSL_PROTO_DTLS) + if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM && + ssl->in_left > ssl->next_record_offset ) + { + MBEDTLS_SSL_DEBUG_MSG( 3, ( "ssl_check_pending: more records within current datagram" ) ); + return( 1 ); + } +#endif /* MBEDTLS_SSL_PROTO_DTLS */ + + /* + * Case C: A handshake message is being processed. + */ + + if( ssl->in_hslen > 0 && ssl->in_hslen < ssl->in_msglen ) + { + MBEDTLS_SSL_DEBUG_MSG( 3, ( "ssl_check_pending: more handshake messages within current record" ) ); + return( 1 ); + } + + /* + * Case D: An application data message is being processed + */ + if( ssl->in_offt != NULL ) + { + MBEDTLS_SSL_DEBUG_MSG( 3, ( "ssl_check_pending: application data record is being processed" ) ); + return( 1 ); + } + + /* + * In all other cases, the rest of the message can be dropped. + * As in ssl_read_record_layer, this needs to be adapted if + * we implement support for multiple alerts in single records. + */ + + MBEDTLS_SSL_DEBUG_MSG( 3, ( "ssl_check_pending: nothing pending" ) ); + return( 0 ); +} + uint32_t mbedtls_ssl_get_verify_result( const mbedtls_ssl_context *ssl ) { if( ssl->session != NULL ) @@ -6892,42 +6950,8 @@ int mbedtls_ssl_read( mbedtls_ssl_context *ssl, unsigned char *buf, size_t len ) } } - /* - * TODO - * - * The logic should be streamlined here: - * - * Instead of - * - * - Manually checking whether ssl->in_offt is NULL - * - Fetching a new record if yes - * - Setting ssl->in_offt if one finds an application record - * - Resetting keep_current_message after handling the application data - * - * one should - * - * - Adapt read_record to set ssl->in_offt automatically - * when a new application data record is processed. - * - Always call mbedtls_ssl_read_record here. - * - * This way, the logic of ssl_read would be much clearer: - * - * (1) Always call record layer and see what kind of record is on - * and have it ready for consumption (in particular, in_offt - * properly set for application data records). - * (2) If it's application data (either freshly fetched - * or something already being partially processed), - * serve the read request from it. - * (3) If it's something different from application data, - * handle it accordingly, e.g. potentially start a - * renegotiation. - * - * This will also remove the need to manually reset - * ssl->keep_current_message = 0 below. - * - */ - - if( ssl->in_offt == NULL ) + /* Loop as long as no application data record is available */ + while( ssl->in_offt == NULL ) { /* Start timer if not already running */ if( ssl->f_get_timer != NULL && @@ -6981,7 +7005,9 @@ int mbedtls_ssl_read( mbedtls_ssl_context *ssl, unsigned char *buf, size_t len ) /* With DTLS, drop the packet (probably from last handshake) */ #if defined(MBEDTLS_SSL_PROTO_DTLS) if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM ) - return( MBEDTLS_ERR_SSL_WANT_READ ); + { + continue; + } #endif return( MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE ); } @@ -6996,7 +7022,9 @@ int mbedtls_ssl_read( mbedtls_ssl_context *ssl, unsigned char *buf, size_t len ) /* With DTLS, drop the packet (probably from last handshake) */ #if defined(MBEDTLS_SSL_PROTO_DTLS) if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM ) - return( MBEDTLS_ERR_SSL_WANT_READ ); + { + continue; + } #endif return( MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE ); } @@ -7069,7 +7097,25 @@ int mbedtls_ssl_read( mbedtls_ssl_context *ssl, unsigned char *buf, size_t len ) } } - return( MBEDTLS_ERR_SSL_WANT_READ ); + /* At this point, we don't know whether the renegotiation has been + * completed or not. The cases to consider are the following: + * 1) The renegotiation is complete. In this case, no new record + * has been read yet. + * 2) The renegotiation is incomplete because the client received + * an application data record while awaiting the ServerHello. + * 3) The renegotiation is incomplete because the client received + * a non-handshake, non-application data message while awaiting + * the ServerHello. + * In each of these case, looping will be the proper action: + * - For 1), the next iteration will read a new record and check + * if it's application data. + * - For 2), the loop condition isn't satisfied as application data + * is present, hence continue is the same as break + * - For 3), the loop condition is satisfied and read_record + * will re-deliver the message that was held back by the client + * when expecting the ServerHello. + */ + continue; } #if defined(MBEDTLS_SSL_RENEGOTIATION) else if( ssl->renego_status == MBEDTLS_SSL_RENEGOTIATION_PENDING ) @@ -7324,7 +7370,7 @@ void mbedtls_ssl_transform_free( mbedtls_ssl_transform *transform ) mbedtls_md_free( &transform->md_ctx_enc ); mbedtls_md_free( &transform->md_ctx_dec ); - mbedtls_zeroize( transform, sizeof( mbedtls_ssl_transform ) ); + mbedtls_platform_zeroize( transform, sizeof( mbedtls_ssl_transform ) ); } #if defined(MBEDTLS_X509_CRT_PARSE_C) @@ -7384,7 +7430,7 @@ void mbedtls_ssl_handshake_free( mbedtls_ssl_handshake_params *handshake ) #if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED) if( handshake->psk != NULL ) { - mbedtls_zeroize( handshake->psk, handshake->psk_len ); + mbedtls_platform_zeroize( handshake->psk, handshake->psk_len ); mbedtls_free( handshake->psk ); } #endif @@ -7414,7 +7460,8 @@ void mbedtls_ssl_handshake_free( mbedtls_ssl_handshake_params *handshake ) ssl_flight_free( handshake->flight ); #endif - mbedtls_zeroize( handshake, sizeof( mbedtls_ssl_handshake_params ) ); + mbedtls_platform_zeroize( handshake, + sizeof( mbedtls_ssl_handshake_params ) ); } void mbedtls_ssl_session_free( mbedtls_ssl_session *session ) @@ -7434,7 +7481,7 @@ void mbedtls_ssl_session_free( mbedtls_ssl_session *session ) mbedtls_free( session->ticket ); #endif - mbedtls_zeroize( session, sizeof( mbedtls_ssl_session ) ); + mbedtls_platform_zeroize( session, sizeof( mbedtls_ssl_session ) ); } /* @@ -7449,20 +7496,20 @@ void mbedtls_ssl_free( mbedtls_ssl_context *ssl ) if( ssl->out_buf != NULL ) { - mbedtls_zeroize( ssl->out_buf, MBEDTLS_SSL_BUFFER_LEN ); + mbedtls_platform_zeroize( ssl->out_buf, MBEDTLS_SSL_BUFFER_LEN ); mbedtls_free( ssl->out_buf ); } if( ssl->in_buf != NULL ) { - mbedtls_zeroize( ssl->in_buf, MBEDTLS_SSL_BUFFER_LEN ); + mbedtls_platform_zeroize( ssl->in_buf, MBEDTLS_SSL_BUFFER_LEN ); mbedtls_free( ssl->in_buf ); } #if defined(MBEDTLS_ZLIB_SUPPORT) if( ssl->compress_buf != NULL ) { - mbedtls_zeroize( ssl->compress_buf, MBEDTLS_SSL_BUFFER_LEN ); + mbedtls_platform_zeroize( ssl->compress_buf, MBEDTLS_SSL_BUFFER_LEN ); mbedtls_free( ssl->compress_buf ); } #endif @@ -7493,7 +7540,7 @@ void mbedtls_ssl_free( mbedtls_ssl_context *ssl ) #if defined(MBEDTLS_X509_CRT_PARSE_C) if( ssl->hostname != NULL ) { - mbedtls_zeroize( ssl->hostname, strlen( ssl->hostname ) ); + mbedtls_platform_zeroize( ssl->hostname, strlen( ssl->hostname ) ); mbedtls_free( ssl->hostname ); } #endif @@ -7513,7 +7560,7 @@ void mbedtls_ssl_free( mbedtls_ssl_context *ssl ) MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= free" ) ); /* Actually clear after last debug message */ - mbedtls_zeroize( ssl, sizeof( mbedtls_ssl_context ) ); + mbedtls_platform_zeroize( ssl, sizeof( mbedtls_ssl_context ) ); } /* @@ -7740,11 +7787,17 @@ void mbedtls_ssl_config_free( mbedtls_ssl_config *conf ) #if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED) if( conf->psk != NULL ) { - mbedtls_zeroize( conf->psk, conf->psk_len ); - mbedtls_zeroize( conf->psk_identity, conf->psk_identity_len ); + mbedtls_platform_zeroize( conf->psk, conf->psk_len ); mbedtls_free( conf->psk ); - mbedtls_free( conf->psk_identity ); + conf->psk = NULL; conf->psk_len = 0; + } + + if( conf->psk_identity != NULL ) + { + mbedtls_platform_zeroize( conf->psk_identity, conf->psk_identity_len ); + mbedtls_free( conf->psk_identity ); + conf->psk_identity = NULL; conf->psk_identity_len = 0; } #endif @@ -7753,7 +7806,7 @@ void mbedtls_ssl_config_free( mbedtls_ssl_config *conf ) ssl_key_cert_free( conf->key_cert ); #endif - mbedtls_zeroize( conf, sizeof( mbedtls_ssl_config ) ); + mbedtls_platform_zeroize( conf, sizeof( mbedtls_ssl_config ) ); } #if defined(MBEDTLS_PK_C) && \ |