Module Name:	src
Committed By:	christos
Date:		Tue Jul 19 17:00:02 UTC 2005

Modified Files:
	src/sys/netinet: ip_icmp.c tcp_input.c tcp_output.c tcp_subr.c
	    tcp_timer.c tcp_var.h

Log Message:
Implement PMTU checks from:

        http://www.gont.com.ar/drafts/icmp-attacks-against-tcp.html

1. Don't act on ICMP-need-frag immediately if adhoc checks on the
advertised MTU fail. The MTU update is delayed until a TCP retransmit
happens.
2. Ignore ICMP Source Quench messages meant for TCP connections.

From OpenBSD.


To generate a diff of this commit:
cvs rdiff -r1.92 -r1.93 src/sys/netinet/ip_icmp.c
cvs rdiff -r1.230 -r1.231 src/sys/netinet/tcp_input.c
cvs rdiff -r1.136 -r1.137 src/sys/netinet/tcp_output.c
cvs rdiff -r1.191 -r1.192 src/sys/netinet/tcp_subr.c
cvs rdiff -r1.71 -r1.72 src/sys/netinet/tcp_timer.c
cvs rdiff -r1.126 -r1.127 src/sys/netinet/tcp_var.h

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.