/*
* Flush any data not yet written
*/
int ssl_flush_output(ssl_context * ssl)
{
int ret;
uint8_t *buf;
SSL_DEBUG_MSG(2, ("=> flush output"));
while (ssl->out_left > 0) {
SSL_DEBUG_MSG(2, ("message length: %d, out_left: %d",
5 + ssl->out_msglen, ssl->out_left));
buf = ssl->out_hdr + 5 + ssl->out_msglen - ssl->out_left;
ret = ssl->f_send(ssl->p_send, buf, ssl->out_left);
SSL_DEBUG_RET(2, "ssl->f_send", ret);
if (ret <= 0)
return (ret);
ssl->out_left -= ret;
}
SSL_DEBUG_MSG(2, ("<= flush output"));
return (0);
}
/*
* Fill the input message buffer
*/
int ssl_fetch_input(ssl_context * ssl, size_t nb_want)
{
int ret;
size_t len;
SSL_DEBUG_MSG(2, ("=> fetch input"));
while (ssl->in_left < nb_want) {
len = nb_want - ssl->in_left;
ret = ssl->f_recv(ssl->p_recv, ssl->in_hdr + ssl->in_left, len);
SSL_DEBUG_MSG(2, ("in_left: %d, nb_want: %d",
ssl->in_left, nb_want));
SSL_DEBUG_RET(2, "ssl->f_recv", ret);
if (ret < 0)
return (ret);
ssl->in_left += ret;
}
SSL_DEBUG_MSG(2, ("<= fetch input"));
return (0);
}
static int ssl_write_server_hello( ssl_context *ssl )
{
time_t t;
int ret, n;
size_t ext_len = 0;
unsigned char *buf, *p;
SSL_DEBUG_MSG( 2, ( "=> write server hello" ) );
/*
* 0 . 0 handshake type
* 1 . 3 handshake length
* 4 . 5 protocol version
* 6 . 9 UNIX time()
* 10 . 37 random bytes
*/
buf = ssl->out_msg;
p = buf + 4;
*p++ = (unsigned char) ssl->major_ver;
*p++ = (unsigned char) ssl->minor_ver;
SSL_DEBUG_MSG( 3, ( "server hello, chosen version: [%d:%d]",
buf[4], buf[5] ) );
t = time( NULL );
*p++ = (unsigned char)( t >> 24 );
*p++ = (unsigned char)( t >> 16 );
*p++ = (unsigned char)( t >> 8 );
*p++ = (unsigned char)( t );
SSL_DEBUG_MSG( 3, ( "server hello, current time: %lu", t ) );
if( ( ret = ssl->f_rng( ssl->p_rng, p, 28 ) ) != 0 )
return( ret );
p += 28;
memcpy( ssl->handshake->randbytes + 32, buf + 6, 32 );
SSL_DEBUG_BUF( 3, "server hello, random bytes", buf + 6, 32 );
/*
* 38 . 38 session id length
* 39 . 38+n session id
* 39+n . 40+n chosen ciphersuite
* 41+n . 41+n chosen compression alg.
*/
ssl->session_negotiate->length = n = 32;
*p++ = (unsigned char) ssl->session_negotiate->length;
if( ssl->renegotiation != SSL_INITIAL_HANDSHAKE ||
ssl->f_get_cache == NULL ||
ssl->f_get_cache( ssl->p_get_cache, ssl->session_negotiate ) != 0 )
{
/*
* Not found, create a new session id
*/
ssl->handshake->resume = 0;
ssl->state++;
if( ( ret = ssl->f_rng( ssl->p_rng, ssl->session_negotiate->id,
n ) ) != 0 )
return( ret );
}
else
{
/*
* Found a matching session, resuming it
*/
ssl->handshake->resume = 1;
ssl->state = SSL_SERVER_CHANGE_CIPHER_SPEC;
if( ( ret = ssl_derive_keys( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_derive_keys", ret );
return( ret );
}
}
memcpy( p, ssl->session_negotiate->id, ssl->session_negotiate->length );
p += ssl->session_negotiate->length;
SSL_DEBUG_MSG( 3, ( "server hello, session id len.: %d", n ) );
SSL_DEBUG_BUF( 3, "server hello, session id", buf + 39, n );
SSL_DEBUG_MSG( 3, ( "%s session has been resumed",
ssl->handshake->resume ? "a" : "no" ) );
*p++ = (unsigned char)( ssl->session_negotiate->ciphersuite >> 8 );
*p++ = (unsigned char)( ssl->session_negotiate->ciphersuite );
*p++ = (unsigned char)( ssl->session_negotiate->compression );
SSL_DEBUG_MSG( 3, ( "server hello, chosen ciphersuite: %d",
ssl->session_negotiate->ciphersuite ) );
SSL_DEBUG_MSG( 3, ( "server hello, compress alg.: %d",
ssl->session_negotiate->compression ) );
if( ssl->secure_renegotiation == SSL_SECURE_RENEGOTIATION )
{
SSL_DEBUG_MSG( 3, ( "server hello, prepping for secure renegotiation extension" ) );
ext_len += 5 + ssl->verify_data_len * 2;
SSL_DEBUG_MSG( 3, ( "server hello, total extension length: %d",
ext_len ) );
*p++ = (unsigned char)( ( ext_len >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( ext_len ) & 0xFF );
/*
* Secure renegotiation
*/
SSL_DEBUG_MSG( 3, ( "client hello, secure renegotiation extension" ) );
*p++ = (unsigned char)( ( TLS_EXT_RENEGOTIATION_INFO >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( TLS_EXT_RENEGOTIATION_INFO ) & 0xFF );
*p++ = 0x00;
*p++ = ( ssl->verify_data_len * 2 + 1 ) & 0xFF;
*p++ = ssl->verify_data_len * 2 & 0xFF;
memcpy( p, ssl->peer_verify_data, ssl->verify_data_len );
p += ssl->verify_data_len;
memcpy( p, ssl->own_verify_data, ssl->verify_data_len );
p += ssl->verify_data_len;
}
static int ssl_parse_client_hello( ssl_context *ssl )
{
int ret;
unsigned int i, j;
size_t n;
unsigned int ciph_len, sess_len;
unsigned int comp_len;
unsigned int ext_len = 0;
unsigned char *buf, *p, *ext;
int renegotiation_info_seen = 0;
int handshake_failure = 0;
SSL_DEBUG_MSG( 2, ( "=> parse client hello" ) );
if( ssl->renegotiation == SSL_INITIAL_HANDSHAKE &&
( ret = ssl_fetch_input( ssl, 5 ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_fetch_input", ret );
return( ret );
}
buf = ssl->in_hdr;
#if defined(POLARSSL_SSL_SRV_SUPPORT_SSLV2_CLIENT_HELLO)
if( ( buf[0] & 0x80 ) != 0 )
return ssl_parse_client_hello_v2( ssl );
#endif
SSL_DEBUG_BUF( 4, "record header", buf, 5 );
SSL_DEBUG_MSG( 3, ( "client hello v3, message type: %d",
buf[0] ) );
SSL_DEBUG_MSG( 3, ( "client hello v3, message len.: %d",
( buf[3] << 8 ) | buf[4] ) );
SSL_DEBUG_MSG( 3, ( "client hello v3, protocol ver: [%d:%d]",
buf[1], buf[2] ) );
/*
* SSLv3 Client Hello
*
* Record layer:
* 0 . 0 message type
* 1 . 2 protocol version
* 3 . 4 message length
*/
if( buf[0] != SSL_MSG_HANDSHAKE ||
buf[1] != SSL_MAJOR_VERSION_3 )
{
SSL_DEBUG_MSG( 1, ( "bad client hello message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_CLIENT_HELLO );
}
n = ( buf[3] << 8 ) | buf[4];
if( n < 45 || n > 512 )
{
SSL_DEBUG_MSG( 1, ( "bad client hello message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_CLIENT_HELLO );
}
if( ssl->renegotiation == SSL_INITIAL_HANDSHAKE &&
( ret = ssl_fetch_input( ssl, 5 + n ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_fetch_input", ret );
return( ret );
}
buf = ssl->in_msg;
if( !ssl->renegotiation )
n = ssl->in_left - 5;
else
n = ssl->in_msglen;
ssl->handshake->update_checksum( ssl, buf, n );
/*
* SSL layer:
* 0 . 0 handshake type
* 1 . 3 handshake length
* 4 . 5 protocol version
* 6 . 9 UNIX time()
* 10 . 37 random bytes
* 38 . 38 session id length
* 39 . 38+x session id
* 39+x . 40+x ciphersuitelist length
* 41+x . .. ciphersuitelist
* .. . .. compression alg.
* .. . .. extensions
*/
SSL_DEBUG_BUF( 4, "record contents", buf, n );
SSL_DEBUG_MSG( 3, ( "client hello v3, handshake type: %d",
buf[0] ) );
SSL_DEBUG_MSG( 3, ( "client hello v3, handshake len.: %d",
( buf[1] << 16 ) | ( buf[2] << 8 ) | buf[3] ) );
SSL_DEBUG_MSG( 3, ( "client hello v3, max. version: [%d:%d]",
buf[4], buf[5] ) );
/*
* Check the handshake type and protocol version
*/
if( buf[0] != SSL_HS_CLIENT_HELLO ||
buf[4] != SSL_MAJOR_VERSION_3 )
{
SSL_DEBUG_MSG( 1, ( "bad client hello message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_CLIENT_HELLO );
}
ssl->major_ver = SSL_MAJOR_VERSION_3;
ssl->minor_ver = ( buf[5] <= SSL_MINOR_VERSION_3 )
? buf[5] : SSL_MINOR_VERSION_3;
if( ssl->minor_ver < ssl->min_minor_ver )
{
SSL_DEBUG_MSG( 1, ( "client only supports ssl smaller than minimum"
" [%d:%d] < [%d:%d]", ssl->major_ver, ssl->minor_ver,
ssl->min_major_ver, ssl->min_minor_ver ) );
ssl_send_alert_message( ssl, SSL_ALERT_LEVEL_FATAL,
SSL_ALERT_MSG_PROTOCOL_VERSION );
return( POLARSSL_ERR_SSL_BAD_HS_PROTOCOL_VERSION );
}
ssl->max_major_ver = buf[4];
ssl->max_minor_ver = buf[5];
memcpy( ssl->handshake->randbytes, buf + 6, 32 );
/*
* Check the handshake message length
*/
if( buf[1] != 0 || n != (unsigned int) 4 + ( ( buf[2] << 8 ) | buf[3] ) )
{
SSL_DEBUG_MSG( 1, ( "bad client hello message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_CLIENT_HELLO );
}
/*
* Check the session length
*/
sess_len = buf[38];
if( sess_len > 32 )
{
SSL_DEBUG_MSG( 1, ( "bad client hello message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_CLIENT_HELLO );
}
ssl->session_negotiate->length = sess_len;
memset( ssl->session_negotiate->id, 0,
sizeof( ssl->session_negotiate->id ) );
memcpy( ssl->session_negotiate->id, buf + 39,
ssl->session_negotiate->length );
/*
* Check the ciphersuitelist length
*/
ciph_len = ( buf[39 + sess_len] << 8 )
| ( buf[40 + sess_len] );
if( ciph_len < 2 || ciph_len > 256 || ( ciph_len % 2 ) != 0 )
{
SSL_DEBUG_MSG( 1, ( "bad client hello message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_CLIENT_HELLO );
}
/*
* Check the compression algorithms length
*/
comp_len = buf[41 + sess_len + ciph_len];
if( comp_len < 1 || comp_len > 16 )
{
SSL_DEBUG_MSG( 1, ( "bad client hello message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_CLIENT_HELLO );
}
/*
* Check the extension length
*/
if( n > 42 + sess_len + ciph_len + comp_len )
{
ext_len = ( buf[42 + sess_len + ciph_len + comp_len] << 8 )
| ( buf[43 + sess_len + ciph_len + comp_len] );
if( ( ext_len > 0 && ext_len < 4 ) ||
n != 44 + sess_len + ciph_len + comp_len + ext_len )
{
SSL_DEBUG_MSG( 1, ( "bad client hello message" ) );
SSL_DEBUG_BUF( 3, "Ext", buf + 44 + sess_len + ciph_len + comp_len, ext_len);
return( POLARSSL_ERR_SSL_BAD_HS_CLIENT_HELLO );
}
}
ssl->session_negotiate->compression = SSL_COMPRESS_NULL;
#if defined(POLARSSL_ZLIB_SUPPORT)
for( i = 0; i < comp_len; ++i )
{
if( buf[42 + sess_len + ciph_len + i] == SSL_COMPRESS_DEFLATE )
{
ssl->session_negotiate->compression = SSL_COMPRESS_DEFLATE;
break;
}
}
#endif
SSL_DEBUG_BUF( 3, "client hello, random bytes",
buf + 6, 32 );
SSL_DEBUG_BUF( 3, "client hello, session id",
buf + 38, sess_len );
SSL_DEBUG_BUF( 3, "client hello, ciphersuitelist",
buf + 41 + sess_len, ciph_len );
SSL_DEBUG_BUF( 3, "client hello, compression",
buf + 42 + sess_len + ciph_len, comp_len );
/*
* Check for TLS_EMPTY_RENEGOTIATION_INFO_SCSV
*/
for( i = 0, p = buf + 41 + sess_len; i < ciph_len; i += 2, p += 2 )
{
if( p[0] == 0 && p[1] == SSL_EMPTY_RENEGOTIATION_INFO )
{
SSL_DEBUG_MSG( 3, ( "received TLS_EMPTY_RENEGOTIATION_INFO " ) );
if( ssl->renegotiation == SSL_RENEGOTIATION )
{
SSL_DEBUG_MSG( 1, ( "received RENEGOTIATION SCSV during renegotiation" ) );
if( ( ret = ssl_send_fatal_handshake_failure( ssl ) ) != 0 )
return( ret );
return( POLARSSL_ERR_SSL_BAD_HS_CLIENT_HELLO );
}
ssl->secure_renegotiation = SSL_SECURE_RENEGOTIATION;
break;
}
}
/*
* Search for a matching ciphersuite
*/
for( i = 0; ssl->ciphersuites[ssl->minor_ver][i] != 0; i++ )
{
for( j = 0, p = buf + 41 + sess_len; j < ciph_len;
j += 2, p += 2 )
{
if( p[0] == 0 && p[1] == ssl->ciphersuites[ssl->minor_ver][i] &&
ssl_get_ciphersuite_min_version( p[1] ) <= ssl->minor_ver )
goto have_ciphersuite;
}
}
SSL_DEBUG_MSG( 1, ( "got no ciphersuites in common" ) );
return( POLARSSL_ERR_SSL_NO_CIPHER_CHOSEN );
have_ciphersuite:
ssl->session_negotiate->ciphersuite = ssl->ciphersuites[ssl->minor_ver][i];
ssl_optimize_checksum( ssl, ssl->session_negotiate->ciphersuite );
ext = buf + 44 + sess_len + ciph_len + comp_len;
while( ext_len )
{
unsigned int ext_id = ( ( ext[0] << 8 )
| ( ext[1] ) );
unsigned int ext_size = ( ( ext[2] << 8 )
| ( ext[3] ) );
if( ext_size + 4 > ext_len )
{
SSL_DEBUG_MSG( 1, ( "bad client hello message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_CLIENT_HELLO );
}
switch( ext_id )
{
case TLS_EXT_SERVERNAME:
SSL_DEBUG_MSG( 3, ( "found ServerName extension" ) );
if( ssl->f_sni == NULL )
break;
ret = ssl_parse_servername_ext( ssl, ext + 4, ext_size );
if( ret != 0 )
return( ret );
break;
case TLS_EXT_RENEGOTIATION_INFO:
SSL_DEBUG_MSG( 3, ( "found renegotiation extension" ) );
renegotiation_info_seen = 1;
ret = ssl_parse_renegotiation_info( ssl, ext + 4, ext_size );
if( ret != 0 )
return( ret );
break;
case TLS_EXT_SIG_ALG:
SSL_DEBUG_MSG( 3, ( "found signature_algorithms extension" ) );
if( ssl->renegotiation == SSL_RENEGOTIATION )
break;
ret = ssl_parse_signature_algorithms_ext( ssl, ext + 4, ext_size );
if( ret != 0 )
return( ret );
break;
default:
SSL_DEBUG_MSG( 3, ( "unknown extension found: %d (ignoring)",
ext_id ) );
}
ext_len -= 4 + ext_size;
ext += 4 + ext_size;
if( ext_len > 0 && ext_len < 4 )
{
SSL_DEBUG_MSG( 1, ( "bad client hello message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_CLIENT_HELLO );
}
}
/*
* Renegotiation security checks
*/
if( ssl->secure_renegotiation == SSL_LEGACY_RENEGOTIATION &&
ssl->allow_legacy_renegotiation == SSL_LEGACY_BREAK_HANDSHAKE )
{
SSL_DEBUG_MSG( 1, ( "legacy renegotiation, breaking off handshake" ) );
handshake_failure = 1;
}
else if( ssl->renegotiation == SSL_RENEGOTIATION &&
ssl->secure_renegotiation == SSL_SECURE_RENEGOTIATION &&
renegotiation_info_seen == 0 )
{
SSL_DEBUG_MSG( 1, ( "renegotiation_info extension missing (secure)" ) );
handshake_failure = 1;
}
else if( ssl->renegotiation == SSL_RENEGOTIATION &&
ssl->secure_renegotiation == SSL_LEGACY_RENEGOTIATION &&
ssl->allow_legacy_renegotiation == SSL_LEGACY_NO_RENEGOTIATION )
{
SSL_DEBUG_MSG( 1, ( "legacy renegotiation not allowed" ) );
handshake_failure = 1;
}
else if( ssl->renegotiation == SSL_RENEGOTIATION &&
ssl->secure_renegotiation == SSL_LEGACY_RENEGOTIATION &&
renegotiation_info_seen == 1 )
{
SSL_DEBUG_MSG( 1, ( "renegotiation_info extension present (legacy)" ) );
handshake_failure = 1;
}
if( handshake_failure == 1 )
{
if( ( ret = ssl_send_fatal_handshake_failure( ssl ) ) != 0 )
return( ret );
return( POLARSSL_ERR_SSL_BAD_HS_CLIENT_HELLO );
}
ssl->in_left = 0;
ssl->state++;
SSL_DEBUG_MSG( 2, ( "<= parse client hello" ) );
return( 0 );
}
static int ssl_parse_client_hello_v2( ssl_context *ssl )
{
int ret;
unsigned int i, j;
size_t n;
unsigned int ciph_len, sess_len, chal_len;
unsigned char *buf, *p;
SSL_DEBUG_MSG( 2, ( "=> parse client hello v2" ) );
if( ssl->renegotiation != SSL_INITIAL_HANDSHAKE )
{
SSL_DEBUG_MSG( 1, ( "client hello v2 illegal for renegotiation" ) );
if( ( ret = ssl_send_fatal_handshake_failure( ssl ) ) != 0 )
return( ret );
return( POLARSSL_ERR_SSL_BAD_HS_CLIENT_HELLO );
}
buf = ssl->in_hdr;
SSL_DEBUG_BUF( 4, "record header", buf, 5 );
SSL_DEBUG_MSG( 3, ( "client hello v2, message type: %d",
buf[2] ) );
SSL_DEBUG_MSG( 3, ( "client hello v2, message len.: %d",
( ( buf[0] & 0x7F ) << 8 ) | buf[1] ) );
SSL_DEBUG_MSG( 3, ( "client hello v2, max. version: [%d:%d]",
buf[3], buf[4] ) );
/*
* SSLv2 Client Hello
*
* Record layer:
* 0 . 1 message length
*
* SSL layer:
* 2 . 2 message type
* 3 . 4 protocol version
*/
if( buf[2] != SSL_HS_CLIENT_HELLO ||
buf[3] != SSL_MAJOR_VERSION_3 )
{
SSL_DEBUG_MSG( 1, ( "bad client hello message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_CLIENT_HELLO );
}
n = ( ( buf[0] << 8 ) | buf[1] ) & 0x7FFF;
if( n < 17 || n > 512 )
{
SSL_DEBUG_MSG( 1, ( "bad client hello message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_CLIENT_HELLO );
}
ssl->major_ver = SSL_MAJOR_VERSION_3;
ssl->minor_ver = ( buf[4] <= SSL_MINOR_VERSION_3 )
? buf[4] : SSL_MINOR_VERSION_3;
if( ssl->minor_ver < ssl->min_minor_ver )
{
SSL_DEBUG_MSG( 1, ( "client only supports ssl smaller than minimum"
" [%d:%d] < [%d:%d]", ssl->major_ver, ssl->minor_ver,
ssl->min_major_ver, ssl->min_minor_ver ) );
ssl_send_alert_message( ssl, SSL_ALERT_LEVEL_FATAL,
SSL_ALERT_MSG_PROTOCOL_VERSION );
return( POLARSSL_ERR_SSL_BAD_HS_PROTOCOL_VERSION );
}
ssl->max_major_ver = buf[3];
ssl->max_minor_ver = buf[4];
if( ( ret = ssl_fetch_input( ssl, 2 + n ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_fetch_input", ret );
return( ret );
}
ssl->handshake->update_checksum( ssl, buf + 2, n );
buf = ssl->in_msg;
n = ssl->in_left - 5;
/*
* 0 . 1 ciphersuitelist length
* 2 . 3 session id length
* 4 . 5 challenge length
* 6 . .. ciphersuitelist
* .. . .. session id
* .. . .. challenge
*/
SSL_DEBUG_BUF( 4, "record contents", buf, n );
ciph_len = ( buf[0] << 8 ) | buf[1];
sess_len = ( buf[2] << 8 ) | buf[3];
chal_len = ( buf[4] << 8 ) | buf[5];
SSL_DEBUG_MSG( 3, ( "ciph_len: %d, sess_len: %d, chal_len: %d",
ciph_len, sess_len, chal_len ) );
/*
* Make sure each parameter length is valid
*/
if( ciph_len < 3 || ( ciph_len % 3 ) != 0 )
{
SSL_DEBUG_MSG( 1, ( "bad client hello message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_CLIENT_HELLO );
}
if( sess_len > 32 )
{
SSL_DEBUG_MSG( 1, ( "bad client hello message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_CLIENT_HELLO );
}
if( chal_len < 8 || chal_len > 32 )
{
SSL_DEBUG_MSG( 1, ( "bad client hello message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_CLIENT_HELLO );
}
if( n != 6 + ciph_len + sess_len + chal_len )
{
SSL_DEBUG_MSG( 1, ( "bad client hello message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_CLIENT_HELLO );
}
SSL_DEBUG_BUF( 3, "client hello, ciphersuitelist",
buf + 6, ciph_len );
SSL_DEBUG_BUF( 3, "client hello, session id",
buf + 6 + ciph_len, sess_len );
SSL_DEBUG_BUF( 3, "client hello, challenge",
buf + 6 + ciph_len + sess_len, chal_len );
p = buf + 6 + ciph_len;
ssl->session_negotiate->length = sess_len;
memset( ssl->session_negotiate->id, 0, sizeof( ssl->session_negotiate->id ) );
memcpy( ssl->session_negotiate->id, p, ssl->session_negotiate->length );
p += sess_len;
memset( ssl->handshake->randbytes, 0, 64 );
memcpy( ssl->handshake->randbytes + 32 - chal_len, p, chal_len );
/*
* Check for TLS_EMPTY_RENEGOTIATION_INFO_SCSV
*/
for( i = 0, p = buf + 6; i < ciph_len; i += 3, p += 3 )
{
if( p[0] == 0 && p[1] == 0 && p[2] == SSL_EMPTY_RENEGOTIATION_INFO )
{
SSL_DEBUG_MSG( 3, ( "received TLS_EMPTY_RENEGOTIATION_INFO " ) );
if( ssl->renegotiation == SSL_RENEGOTIATION )
{
SSL_DEBUG_MSG( 1, ( "received RENEGOTIATION SCSV during renegotiation" ) );
if( ( ret = ssl_send_fatal_handshake_failure( ssl ) ) != 0 )
return( ret );
return( POLARSSL_ERR_SSL_BAD_HS_CLIENT_HELLO );
}
ssl->secure_renegotiation = SSL_SECURE_RENEGOTIATION;
break;
}
}
for( i = 0; ssl->ciphersuites[ssl->minor_ver][i] != 0; i++ )
{
for( j = 0, p = buf + 6; j < ciph_len; j += 3, p += 3 )
{
if( p[0] == 0 &&
p[1] == 0 &&
p[2] == ssl->ciphersuites[ssl->minor_ver][i] )
goto have_ciphersuite_v2;
}
}
SSL_DEBUG_MSG( 1, ( "got no ciphersuites in common" ) );
return( POLARSSL_ERR_SSL_NO_CIPHER_CHOSEN );
have_ciphersuite_v2:
ssl->session_negotiate->ciphersuite = ssl->ciphersuites[ssl->minor_ver][i];
ssl_optimize_checksum( ssl, ssl->session_negotiate->ciphersuite );
/*
* SSLv2 Client Hello relevant renegotiation security checks
*/
if( ssl->secure_renegotiation == SSL_LEGACY_RENEGOTIATION &&
ssl->allow_legacy_renegotiation == SSL_LEGACY_BREAK_HANDSHAKE )
{
SSL_DEBUG_MSG( 1, ( "legacy renegotiation, breaking off handshake" ) );
if( ( ret = ssl_send_fatal_handshake_failure( ssl ) ) != 0 )
return( ret );
return( POLARSSL_ERR_SSL_BAD_HS_CLIENT_HELLO );
}
ssl->in_left = 0;
ssl->state++;
SSL_DEBUG_MSG( 2, ( "<= parse client hello v2" ) );
return( 0 );
}