linux/net/dccp
David S. Miller 81aded2467 ipv6: Handle PMTU in ICMP error handlers.
One tricky issue on the ipv6 side vs. ipv4 is that the ICMP callouts
to handle the error pass the 32-bit info cookie in network byte order
whereas ipv4 passes it around in host byte order.

Like the ipv4 side, we have two helper functions.  One for when we
have a socket context and one for when we do not.

ip6ip6 tunnels are not handled here, because they handle PMTU events
by essentially relaying another ICMP packet-too-big message back to
the original sender.

This patch allows us to get rid of rt6_do_pmtu_disc().  It handles all
kinds of situations that simply cannot happen when we do the PMTU
update directly using a fully resolved route.

In fact, the "plen == 128" check in ip6_rt_update_pmtu() can very
likely be removed or changed into a BUG_ON() check.  We should never
have a prefixed ipv6 route when we get there.

Another piece of strange history here is that TCP and DCCP, unlike in
ipv4, never invoke the update_pmtu() method from their ICMP error
handlers.  This is incredibly astonishing since this is the context
where we have the most accurate context in which to make a PMTU
update, namely we have a fully connected socket and associated cached
socket route.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-15 14:54:11 -07:00
..
ccids net: cleanup unsigned to unsigned int 2012-04-15 12:44:40 -04:00
ackvec.c net: Add export.h for EXPORT_SYMBOL/THIS_MODULE to non-modules 2011-10-31 19:30:30 -04:00
ackvec.h dccp ccid-2: Separate option parsing from CCID processing 2010-11-15 07:12:01 +01:00
ccid.c dccp: cosmetics of info message 2011-07-04 12:37:13 -06:00
ccid.h dccp: Return-value convention of hc_tx_send_packet() 2010-10-28 10:27:00 -07:00
dccp.h net: cleanup unsigned to unsigned int 2012-04-15 12:44:40 -04:00
diag.c inet_diag: Rename inet_diag_req into inet_diag_req_v2 2012-01-11 12:56:06 -08:00
feat.c net: fix assignment of 0/1 to bool variables. 2011-12-19 22:27:29 -05:00
feat.h dccp: support for the exchange of NN options in established state 1/2 2011-08-01 07:52:34 -06:00
input.c net: cleanup unsigned to unsigned int 2012-04-15 12:44:40 -04:00
ipv4.c inet: makes syn_ack_timeout mandatory 2012-04-14 15:24:26 -04:00
ipv6.c ipv6: Handle PMTU in ICMP error handlers. 2012-06-15 14:54:11 -07:00
ipv6.h Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
Kconfig Docs/Kconfig: Update: osdl.org -> linuxfoundation.org 2010-11-15 23:50:13 +01:00
Makefile dccp: Policy-based packet dequeueing infrastructure 2010-12-07 13:47:12 +01:00
minisocks.c dccp: fix bug in sequence number validation during connection setup 2012-03-03 09:02:52 -07:00
options.c net: fix assignment of 0/1 to bool variables. 2011-12-19 22:27:29 -05:00
output.c dccp: fix bug in sequence number validation during connection setup 2012-03-03 09:02:52 -07:00
probe.c dccp: Fix compile warning in probe code. 2011-12-01 14:45:49 -05:00
proto.c net: include/net/sock.h cleanup 2012-05-17 04:50:21 -04:00
qpolicy.c dccp qpolicy: Parameter checking of cmsg qpolicy parameters 2010-12-07 13:47:12 +01:00
sysctl.c net: Convert all sysctl registrations to register_net_sysctl 2012-04-20 21:22:30 -04:00
timer.c net: Add export.h for EXPORT_SYMBOL/THIS_MODULE to non-modules 2011-10-31 19:30:30 -04:00