On 26/09/2019 06:42, ratheesh kannoth wrote: > Hi list, > > i am trying to understand write sequence number and read sequence > number. Setup is simple client server with tls v1.2. > > when i made write sequence number to 0 (ssl/t1_enc.c --> > s->s2->write_sequence to 0). i commented out all increment operate on > write_sequence number. But s->s2->read_sequence number is unmodified. I assume you are using OpenSSL 1.0.2? s->s2 has nothing to do with TLSv1.2. That's for SSLv2 and has been removed from later versions. In 1.0.2 you need to be looking at s->s3->write_sequence and s->s3->write_sequence. It's changed location in later releases. Matt > > But there is no issue in transmission. Could any one guide me to find > the sequence number used in write direction, is stored where ? > > > -Ratheesh >