tcp: rate limit the sending of all RST segmentsHEADmain

Also rate limit the sending of RST segments in the following cases:
* when receiving data on a closed socket.
* when a socket can not be created at the end of the handshake and
  the sysctl-variable net.inet.tcp.syncache.rst_on_sock_fail is 1.
* when an ACK segment is received in SYN SENT state and it does not
  acknowledge the SYN segment.
After this change, there is no need anymore to provide a rstreason
to tcp_dropwithreset(), since it is always BANDLIM_TCP_RST.
This will be a follow-up commit, since it will change the code in a
couple of places, but will not change the functionality.

Reviewed by:		rrs, Nick Banks, Peter Lei
MFC after:		1 week
Sponsored by:		Netflix, Inc.
Differential Revision:	https://reviews.freebsd.org/D51815

0 files changed, 0 insertions, 0 deletions