Compute record expansion at the right time

Depends on the current transform, which might change when retransmitting a
flight containing a Finished message, so compute it only after the transform
is swapped.
This commit is contained in:
Manuel Pégourié-Gonnard 2018-08-20 11:56:14 +02:00
parent 4532329397
commit a1071a58a3

View file

@ -2845,20 +2845,8 @@ int mbedtls_ssl_resend( mbedtls_ssl_context *ssl )
*/
int mbedtls_ssl_flight_transmit( mbedtls_ssl_context *ssl )
{
const int ret_payload = mbedtls_ssl_get_max_out_record_payload( ssl );
const size_t max_record_payload = (size_t) ret_payload;
/* DTLS handshake headers are 12 bytes */
const size_t max_hs_fragment_len = max_record_payload - 12;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> mbedtls_ssl_flight_transmit" ) );
if( ret_payload < 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_get_max_out_record_payload",
ret_payload );
return( ret_payload );
}
if( ssl->handshake->retransmit_state != MBEDTLS_SSL_RETRANS_SENDING )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "initialise flight transmission" ) );
@ -2895,6 +2883,10 @@ int mbedtls_ssl_flight_transmit( mbedtls_ssl_context *ssl )
}
else
{
const int ret_payload = mbedtls_ssl_get_max_out_record_payload( ssl );
const size_t max_record_payload = (size_t) ret_payload;
/* DTLS handshake headers are 12 bytes */
const size_t max_hs_fragment_len = max_record_payload - 12;
const unsigned char * const p = ssl->handshake->cur_msg_p;
const size_t hs_len = cur->len - 12;
const size_t frag_off = p - ( cur->p + 12 );
@ -2902,6 +2894,13 @@ int mbedtls_ssl_flight_transmit( mbedtls_ssl_context *ssl )
const size_t frag_len = rem_len > max_hs_fragment_len
? max_hs_fragment_len : rem_len;
if( ret_payload < 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_get_max_out_record_payload",
ret_payload );
return( ret_payload );
}
if( frag_off == 0 && frag_len != hs_len )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "fragmenting handshake message (%u > %u)",