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path: root/net/netfilter/nf_conntrack_ecache.c
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2009-11-12sysctl net: Remove unused binary sysctl codeEric W. Biederman1-2/+0
Now that sys_sysctl is a compatiblity wrapper around /proc/sys all sysctl strategy routines, and all ctl_name and strategy entries in the sysctl tables are unused, and can be revmoed. In addition neigh_sysctl_register has been modified to no longer take a strategy argument and it's callers have been modified not to pass one. Cc: "David Miller" <davem@davemloft.net> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> Cc: netdev@vger.kernel.org Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2009-06-13netfilter: conntrack: optional reliable conntrack event deliveryPablo Neira Ayuso1-2/+26
This patch improves ctnetlink event reliability if one broadcast listener has set the NETLINK_BROADCAST_ERROR socket option. The logic is the following: if an event delivery fails, we keep the undelivered events in the missed event cache. Once the next packet arrives, we add the new events (if any) to the missed events in the cache and we try a new delivery, and so on. Thus, if ctnetlink fails to deliver an event, we try to deliver them once we see a new packet. Therefore, we may lose state transitions but the userspace process gets in sync at some point. At worst case, if no events were delivered to userspace, we make sure that destroy events are successfully delivered. Basically, if ctnetlink fails to deliver the destroy event, we remove the conntrack entry from the hashes and we insert them in the dying list, which contains inactive entries. Then, the conntrack timer is added with an extra grace timeout of random32() % 15 seconds to trigger the event again (this grace timeout is tunable via /proc). The use of a limited random timeout value allows distributing the "destroy" resends, thus, avoiding accumulating lots "destroy" events at the same time. Event delivery may re-order but we can identify them by means of the tuple plus the conntrack ID. The maximum number of conntrack entries (active or inactive) is still handled by nf_conntrack_max. Thus, we may start dropping packets at some point if we accumulate a lot of inactive conntrack entries that did not successfully report the destroy event to userspace. During my stress tests consisting of setting a very small buffer of 2048 bytes for conntrackd and the NETLINK_BROADCAST_ERROR socket flag, and generating lots of very small connections, I noticed very few destroy entries on the fly waiting to be resend. A simple way to test this patch consist of creating a lot of entries, set a very small Netlink buffer in conntrackd (+ a patch which is not in the git tree to set the BROADCAST_ERROR flag) and invoke `conntrack -F'. For expectations, no changes are introduced in this patch. Currently, event delivery is only done for new expectations (no events from expectation expiration, removal and confirmation). In that case, they need a per-expectation event cache to implement the same idea that is exposed in this patch. This patch can be useful to provide reliable flow-accouting. We still have to add a new conntrack extension to store the creation and destroy time. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-06-13netfilter: conntrack: move event caching to conntrack extension infrastructurePablo Neira Ayuso1-68/+117
This patch reworks the per-cpu event caching to use the conntrack extension infrastructure. The main drawback is that we consume more memory per conntrack if event delivery is enabled. This patch is required by the reliable event delivery that follows to this patch. BTW, this patch allows you to enable/disable event delivery via /proc/sys/net/netfilter/nf_conntrack_events in runtime, although you can still disable event caching as compilation option. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-06-03netfilter: conntrack: replace notify chain by function pointerPablo Neira Ayuso1-16/+67
This patch removes the notify chain infrastructure and replace it by a simple function pointer. This issue has been mentioned in the mailing list several times: the use of the notify chain adds too much overhead for something that is only used by ctnetlink. This patch also changes nfnetlink_send(). It seems that gfp_any() returns GFP_KERNEL for user-context request, like those via ctnetlink, inside the RCU read-side section which is not valid. Using GFP_KERNEL is also evil since netlink may schedule(), this leads to "scheduling while atomic" bug reports. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2008-11-18netfilter: ctnetlink: deliver events for conntracks changed from userspacePablo Neira Ayuso1-3/+11
As for now, the creation and update of conntracks via ctnetlink do not propagate an event to userspace. This can result in inconsistent situations if several userspace processes modify the connection tracking table by means of ctnetlink at the same time. Specifically, using the conntrack command line tool and conntrackd at the same time can trigger unconsistencies. This patch also modifies the event cache infrastructure to pass the process PID and the ECHO flag to nfnetlink_send() to report back to userspace if the process that triggered the change needs so. Based on a suggestion from Patrick McHardy. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Patrick McHardy <kaber@trash.net>
2008-10-08netfilter: netns nf_conntrack: per-netns event cacheAlexey Dobriyan1-7/+19
Heh, last minute proof-reading of this patch made me think, that this is actually unneeded, simply because "ct" pointers will be different for different conntracks in different netns, just like they are different in one netns. Not so sure anymore. [Patrick: pointers will be different, flushing can only be done while inactive though and thus it needs to be per netns] Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Patrick McHardy <kaber@trash.net>
2007-07-10[NETFILTER]: nf_conntrack_expect: function naming unificationPatrick McHardy1-8/+8
Currently there is a wild mix of nf_conntrack_expect_, nf_ct_exp_, expect_, exp_, ... Consistently use nf_ct_ as prefix for exported functions. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[NETFILTER]: nf_conntrack: uninline notifier registration functionsPatrick McHardy1-0/+23
Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02[NETFILTER]: nf_conntrack: fix header inclusions for helpersYasuyuki Kozakai1-4/+0
Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02[NETFILTER]: nf_conntrack: EXPORT_SYMBOL cleanupPatrick McHardy1-0/+6
- move EXPORT_SYMBOL next to exported symbol - use EXPORT_SYMBOL_GPL since this is what the original code used Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02[NETFILTER]: nf_conntrack: rename struct nf_conntrack_protocolMartin Josefsson1-1/+1
Rename 'struct nf_conntrack_protocol' to 'struct nf_conntrack_l4proto' in order to help distinguish it from 'struct nf_conntrack_l3proto'. It gets rather confusing with 'nf_conntrack_protocol'. Signed-off-by: Martin Josefsson <gandalf@wlug.westbo.se> Signed-off-by: Patrick McHardy <kaber@trash.net>
2006-12-02[NETFILTER]: nf_conntrack: split out the event cacheMartin Josefsson1-0/+91
This patch splits out the event cache into its own file nf_conntrack_ecache.c Signed-off-by: Martin Josefsson <gandalf@wlug.westbo.se> Signed-off-by: Patrick McHardy <kaber@trash.net>