linux/net
Gerrit Renker ddab05568e dccp: Clean up slow-path input processing
This patch rearranges the order of statements of the slow-path input processing
(i.e. any other state than OPEN), to resolve the following issues.

 1. Dependencies: the order of statements now better matches RFC 4340, 8.5, i.e.
    step 7 is before step 9 (previously 9 was before 7), and parsing options in
    step 8 (which can consume resources) now comes after step 7.
 2. Bug-fix: in state CLOSED, there should not be any sequence number checking
    or option processing. This is why the test for CLOSED has been moved after
    the test for LISTEN.
 3. As before sequence number checks are omitted if in state LISTEN/REQUEST, due
    to the note underneath the table in RFC 4340, 7.5.3.
 4. Packets are now passed on to Ack Vector / CCID processing only after
    - step 7  (receive unexpected packets), 
    - step 9  (receive Reset),
    - step 13 (receive CloseReq),
    - step 14 (receive Close)
    and only if the state is PARTOPEN. This simplifies CCID processing:
    - in LISTEN/CLOSED the CCIDs are non-existent;
    - in RESPOND/REQUEST the CCIDs have not yet been negotiated;
    - in CLOSEREQ and active-CLOSING the node has already closed this socket;
    - in passive-CLOSING the client is waiting for its Reset.
    In the last case, RFC 4340, 8.3 leaves it open to ignore further incoming
    data, which is the approach taken here.

As a result of (3), CCID processing is now indeed confined to OPEN/PARTOPEN
states, i.e. congestion control is performed only on the flow of data packets. 

This avoids pathological cases of doing congestion control on those messages
which set up and terminate the connection. 

I have done a few checks to see if this creates a problem in other parts of
the code. This seems not to be the case; even if there were one, it would be
better to fix it than to perform congestion control on Close/Request/Response
messages. Similarly for Ack Vectors (as they depend on the negotiated CCID).

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-09-04 07:45:39 +02:00
..
9p flag parameters: socket and socketpair 2008-07-24 10:47:27 -07:00
802 list_for_each_rcu must die: networking 2008-07-25 10:53:27 -07:00
8021q netdev: Handle ->addr_list_lock just like ->_xmit_lock for lockdep. 2008-07-22 14:16:42 -07:00
appletalk net: convert BUG_TRAP to generic WARN_ON 2008-07-25 21:43:18 -07:00
atm atm: fix const assignment/discard warnings in the ATM networking driver 2008-07-30 16:31:46 -07:00
ax25 AX.25: Fix sysctl registration if !CONFIG_AX25_DAMA_SLAVE 2008-08-05 18:46:57 -07:00
bluetooth [Bluetooth] Consolidate maintainers information 2008-08-18 13:23:53 +02:00
bridge bridge: show offload settings 2008-08-15 19:51:07 -07:00
can netns: Use net_eq() to compare net-namespaces for optimization. 2008-07-19 22:34:43 -07:00
core pkt_sched: Prevent livelock in TX queue running. 2008-08-19 04:00:36 -07:00
dccp dccp: Clean up slow-path input processing 2008-09-04 07:45:39 +02:00
decnet netns: Use net_eq() to compare net-namespaces for optimization. 2008-07-19 22:34:43 -07:00
econet netns: Use net_eq() to compare net-namespaces for optimization. 2008-07-19 22:34:43 -07:00
ethernet [NET]: Return more appropriate error from eth_validate_addr(). 2008-04-13 22:45:40 -07:00
ieee80211 wext: Emit event stream entries correctly when compat. 2008-06-16 18:50:49 -07:00
ipv4 tcp/dccp: Consolidate common code for RFC 3390 conversion 2008-09-04 07:45:39 +02:00
ipv6 ipv6: When we droped a packet, we should return NET_RX_DROP instead of 0 2008-08-29 14:27:51 -07:00
ipx netns: Use net_eq() to compare net-namespaces for optimization. 2008-07-19 22:34:43 -07:00
irda Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6 2008-07-20 17:43:29 -07:00
iucv Merge branch 'linus' into cpus4096-for-linus 2008-07-21 17:19:50 +02:00
key net: convert BUG_TRAP to generic WARN_ON 2008-07-25 21:43:18 -07:00
lapb
llc netns: Use net_eq() to compare net-namespaces for optimization. 2008-07-19 22:34:43 -07:00
mac80211 mac80211: Fix debugfs union misuse and pointer corruption 2008-09-02 17:39:50 -04:00
netfilter netfilter: ctnetlink: sleepable allocation with spin lock bh 2008-08-18 21:31:46 -07:00
netlabel netns: Use net_eq() to compare net-namespaces for optimization. 2008-07-19 22:34:43 -07:00
netlink net: convert BUG_TRAP to generic WARN_ON 2008-07-25 21:43:18 -07:00
netrom netdev: Handle ->addr_list_lock just like ->_xmit_lock for lockdep. 2008-07-22 14:16:42 -07:00
packet net: convert BUG_TRAP to generic WARN_ON 2008-07-25 21:43:18 -07:00
rfkill net: rfkill: add missing line break 2008-08-26 20:06:31 -04:00
rose netdev: Handle ->addr_list_lock just like ->_xmit_lock for lockdep. 2008-07-22 14:16:42 -07:00
rxrpc net/rxrpc: Use an IS_ERR test rather than a NULL test 2008-08-13 02:40:48 -07:00
sched pkt_sched: Fix locking of qdisc_root with qdisc_root_sleeping_lock() 2008-08-29 14:27:52 -07:00
sctp sctp: fix random memory dereference with SCTP_HMAC_IDENT option. 2008-08-27 16:09:49 -07:00
sunrpc Merge branch 'linus' into cpus4096 2008-07-28 21:14:43 +02:00
tipc tipc: Don't use structure names which easily globally conflict. 2008-09-02 23:38:32 -07:00
unix Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 2008-07-26 20:23:44 -07:00
wanrouter wanmain.c doesn't need syncppp.h 2008-07-23 23:00:36 +02:00
wireless net/wireless/Kconfig: clarify the description for CONFIG_WIRELESS_EXT_SYSFS 2008-09-02 15:03:19 -04:00
x25 netns: Use net_eq() to compare net-namespaces for optimization. 2008-07-19 22:34:43 -07:00
xfrm ipsec: Fix deadlock in xfrm_state management. 2008-09-02 20:14:15 -07:00
compat.c flag parameters: paccept 2008-07-24 10:47:27 -07:00
Kconfig net: Make "networking" one-click deselectable. 2008-07-30 03:27:53 -07:00
Makefile vlan: uninline __vlan_hwaccel_rx 2008-07-08 03:23:36 -07:00
nonet.c
socket.c SL*B: drop kmem cache argument from constructor 2008-07-26 12:00:07 -07:00
sysctl_net.c missing bits of net-namespace / sysctl 2008-07-27 09:45:34 -07:00
TUNABLE