No memmove: ssl_parse_server_hello()

This commit is contained in:
Manuel Pégourié-Gonnard 2014-09-10 21:23:41 +02:00 committed by Paul Bakker
parent 069eb79043
commit 0b3400dafa

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@ -1032,13 +1032,6 @@ static int ssl_parse_server_hello( ssl_context *ssl )
SSL_DEBUG_MSG( 2, ( "=> parse server hello" ) );
/*
* 0 . 0 handshake type
* 1 . 3 handshake length
* 4 . 5 protocol version
* 6 . 9 UNIX time()
* 10 . 37 random bytes
*/
buf = ssl->in_msg;
if( ( ret = ssl_read_record( ssl ) ) != 0 )
@ -1088,18 +1081,29 @@ static int ssl_parse_server_hello( ssl_context *ssl )
}
#endif /* POLARSSL_SSL_PROTO_DTLS */
ssl_hs_rm_dtls_hdr( ssl );
if( ssl->in_hslen < 42 ||
if( ssl->in_hslen < 38 + ssl_hs_hdr_len( ssl ) ||
buf[0] != SSL_HS_SERVER_HELLO )
{
SSL_DEBUG_MSG( 1, ( "bad server hello message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_SERVER_HELLO );
}
SSL_DEBUG_BUF( 3, "server hello, version", buf + 4, 2 );
/*
* 0 . 1 server_version
* 2 . 33 random (maybe including 4 bytes of Unix time)
* 34 . 34 session_id length = n
* 35 . 34+n session_id
* 35+n . 36+n cipher_suite
* 37+n . 37+n compression_method
*
* 38+n . 39+n extensions length (optional)
* 40+n . .. extensions
*/
buf += ssl_hs_hdr_len( ssl );
SSL_DEBUG_BUF( 3, "server hello, version", buf + 0, 2 );
ssl_read_version( &ssl->major_ver, &ssl->minor_ver,
ssl->transport, buf + 4 );
ssl->transport, buf + 0 );
if( ssl->major_ver < ssl->min_major_ver ||
ssl->minor_ver < ssl->min_minor_ver ||
@ -1119,18 +1123,18 @@ static int ssl_parse_server_hello( ssl_context *ssl )
}
#if defined(POLARSSL_DEBUG_C)
t = ( (uint32_t) buf[6] << 24 )
| ( (uint32_t) buf[7] << 16 )
| ( (uint32_t) buf[8] << 8 )
| ( (uint32_t) buf[9] );
t = ( (uint32_t) buf[2] << 24 )
| ( (uint32_t) buf[3] << 16 )
| ( (uint32_t) buf[4] << 8 )
| ( (uint32_t) buf[5] );
SSL_DEBUG_MSG( 3, ( "server hello, current time: %lu", t ) );
#endif
memcpy( ssl->handshake->randbytes + 32, buf + 6, 32 );
memcpy( ssl->handshake->randbytes + 32, buf + 2, 32 );
n = buf[38];
n = buf[34];
SSL_DEBUG_BUF( 3, "server hello, random bytes", buf + 6, 32 );
SSL_DEBUG_BUF( 3, "server hello, random bytes", buf + 2, 32 );
if( n > 32 )
{
@ -1138,27 +1142,19 @@ static int ssl_parse_server_hello( ssl_context *ssl )
return( POLARSSL_ERR_SSL_BAD_HS_SERVER_HELLO );
}
/*
* 38 . 38 session id length
* 39 . 38+n session id
* 39+n . 40+n chosen ciphersuite
* 41+n . 41+n chosen compression alg.
* 42+n . 43+n extensions length
* 44+n . 44+n+m extensions
*/
if( ssl->in_hslen > 43 + n )
if( ssl->in_hslen > 39 + n )
{
ext_len = ( ( buf[42 + n] << 8 )
| ( buf[43 + n] ) );
ext_len = ( ( buf[38 + n] << 8 )
| ( buf[39 + n] ) );
if( ( ext_len > 0 && ext_len < 4 ) ||
ssl->in_hslen != 44 + n + ext_len )
ssl->in_hslen != ssl_hs_hdr_len( ssl ) + 40 + n + ext_len )
{
SSL_DEBUG_MSG( 1, ( "bad server hello message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_SERVER_HELLO );
}
}
else if( ssl->in_hslen == 42 + n )
else if( ssl->in_hslen == 38 + n )
{
ext_len = 0;
}
@ -1169,12 +1165,12 @@ static int ssl_parse_server_hello( ssl_context *ssl )
}
/* ciphersuite (used later) */
i = ( buf[39 + n] << 8 ) | buf[40 + n];
i = ( buf[35 + n] << 8 ) | buf[36 + n];
/*
* Read and check compression
*/
comp = buf[41 + n];
comp = buf[37 + n];
#if defined(POLARSSL_ZLIB_SUPPORT)
accept_comp = 1;
@ -1209,7 +1205,7 @@ static int ssl_parse_server_hello( ssl_context *ssl )
ssl_optimize_checksum( ssl, ssl->transform_negotiate->ciphersuite_info );
SSL_DEBUG_MSG( 3, ( "server hello, session id len.: %d", n ) );
SSL_DEBUG_BUF( 3, "server hello, session id", buf + 39, n );
SSL_DEBUG_BUF( 3, "server hello, session id", buf + 35, n );
/*
* Check if the session can be resumed
@ -1219,7 +1215,7 @@ static int ssl_parse_server_hello( ssl_context *ssl )
ssl->session_negotiate->ciphersuite != i ||
ssl->session_negotiate->compression != comp ||
ssl->session_negotiate->length != n ||
memcmp( ssl->session_negotiate->id, buf + 39, n ) != 0 )
memcmp( ssl->session_negotiate->id, buf + 35, n ) != 0 )
{
ssl->state++;
ssl->handshake->resume = 0;
@ -1229,7 +1225,7 @@ static int ssl_parse_server_hello( ssl_context *ssl )
ssl->session_negotiate->ciphersuite = i;
ssl->session_negotiate->compression = comp;
ssl->session_negotiate->length = n;
memcpy( ssl->session_negotiate->id, buf + 39, n );
memcpy( ssl->session_negotiate->id, buf + 35, n );
}
else
{
@ -1246,7 +1242,7 @@ static int ssl_parse_server_hello( ssl_context *ssl )
ssl->handshake->resume ? "a" : "no" ) );
SSL_DEBUG_MSG( 3, ( "server hello, chosen ciphersuite: %d", i ) );
SSL_DEBUG_MSG( 3, ( "server hello, compress alg.: %d", buf[41 + n] ) );
SSL_DEBUG_MSG( 3, ( "server hello, compress alg.: %d", buf[37 + n] ) );
i = 0;
while( 1 )
@ -1275,7 +1271,7 @@ static int ssl_parse_server_hello( ssl_context *ssl )
}
ssl->session_negotiate->compression = comp;
ext = buf + 44 + n;
ext = buf + 40 + n;
SSL_DEBUG_MSG( 2, ( "server hello, total extension length: %d", ext_len ) );