TCP MD5 and socket accept

[Stephen Hemminger <shemminger@vyatta.com>]

It looks like the child socket on accept doesn't inherit the MD5 mappings
from the listening socket.  This leads to the situation where the data
after the initial SYN, ACK gets a MD5 mismatch until the child socket
is updated with setsockopt.

My question was this an intentional part of the initial design?

What will break if tcp_create_openreq_child was fixed to copy md5_info if
present?

This all comes about because right now using Quagga a Linux to Linux
works with TCP MD5. But a Linux to Cisco connection fails if using
TCP MD5.