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2019-01-18netfilter: conntrack: remove l4proto init and get_net callbacksFlorian Westphal1-20/+4
Those were needed we still had modular trackers. As we don't have those anymore, prefer direct calls and remove all the (un)register infrastructure associated with this. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18netfilter: conntrack: unify sysctl handlingFlorian Westphal1-35/+1
Due to historical reasons, all l4 trackers register their own sysctls. This leads to copy&pasted boilerplate code, that does exactly same thing, just with different data structure. Place all of this in a single file. This allows to remove the various ctl_table pointers from the ct_netns structure and reduces overall code size. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18netfilter: conntrack: handle builtin l4proto packet functions via direct callsFlorian Westphal1-12/+10
The l4 protocol trackers are invoked via indirect call: l4proto->packet(). With one exception (gre), all l4trackers are builtin, so we can make .packet optional and use a direct call for most protocols. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-12-21netfilter: conntrack: udp: set stream timeout to 2 minutesFlorian Westphal1-1/+1
We have no explicit signal when a UDP stream has terminated, peers just stop sending. For suspected stream connections a timeout of two minutes is sane to keep NAT mapping alive a while longer. It matches tcp conntracks 'timewait' default timeout value. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-12-21netfilter: conntrack: udp: only extend timeout to stream mode after 2sFlorian Westphal1-3/+13
Currently DNS resolvers that send both A and AAAA queries from same source port can trigger stream mode prematurely, which results in non-early-evictable conntrack entry for three minutes, even though DNS requests are done in a few milliseconds. Add a two second grace period where we continue to use the ordinary 30-second default timeout. Its enough for DNS request/response traffic, even if two request/reply packets are involved. ASSURED is still set, else conntrack (and thus a possible NAT mapping ...) gets zapped too in case conntrack table runs full. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-11-03netfilter: conntrack: add nf_{tcp,udp,sctp,icmp,dccp,icmpv6,generic}_pernet()Pablo Neira Ayuso1-8/+3
Expose these functions to access conntrack protocol tracker netns area, nfnetlink_cttimeout needs this. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-09-20netfilter: conntrack: remove l3->l4 mapping informationFlorian Westphal1-60/+2
l4 protocols are demuxed by l3num, l4num pair. However, almost all l4 trackers are l3 agnostic. Only exceptions are: - gre, icmp (ipv4 only) - icmpv6 (ipv6 only) This commit gets rid of the l3 mapping, l4 trackers can now be looked up by their IPPROTO_XXX value alone, which gets rid of the additional l3 indirection. For icmp, ipcmp6 and gre, add a check on state->pf and return -NF_ACCEPT in case we're asked to track e.g. icmpv6-in-ipv4, this seems more fitting than using the generic tracker. Additionally we can kill the 2nd l4proto definitions that were needed for v4/v6 split -- they are now the same so we can use single l4proto struct for each protocol, rather than two. The EXPORT_SYMBOLs can be removed as all these object files are part of nf_conntrack with no external references. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-09-20netfilter: conntrack: remove unused proto arg from netns init functionsFlorian Westphal1-1/+1
Its unused, next patch will remove l4proto->l3proto number to simplify l4 protocol demuxer lookup. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-09-20netfilter: conntrack: deconstify packet callback skb pointerFlorian Westphal1-53/+84
Only two protocols need the ->error() function: icmp and icmpv6. This is because icmp error mssages might be RELATED to an existing connection (e.g. PMTUD, port unreachable and the like), and their ->error() handlers do this. The error callback is already optional, so remove it for udp and call them from ->packet() instead. As the error() callback can call checksum functions that write to skb->csum*, the const qualifier has to be removed as well. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-09-20netfilter: conntrack: remove the l4proto->new() functionFlorian Westphal1-11/+0
->new() gets invoked after ->error() and before ->packet() if a conntrack lookup has found no result for the tuple. We can fold it into ->packet() -- the packet() implementations can check if the conntrack is confirmed (new) or not (already in hash). If its unconfirmed, the conntrack isn't in the hash yet so current skb created a new conntrack entry. Only relevant side effect -- if packet() doesn't return NF_ACCEPT but -NF_ACCEPT (or drop), while the conntrack was just created, then the newly allocated conntrack is freed right away, rather than not created in the first place. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-09-20netfilter: conntrack: pass nf_hook_state to packet and error handlersFlorian Westphal1-25/+29
nf_hook_state contains all the hook meta-information: netns, protocol family, hook location, and so on. Instead of only passing selected information, pass a pointer to entire structure. This will allow to merge the error and the packet handlers and remove the ->new() function in followup patches. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-09-11netfilter: conntrack: timeout interface depend on CONFIG_NF_CONNTRACK_TIMEOUTPablo Neira Ayuso1-10/+10
Now that cttimeout support for nft_ct is in place, these should depend on CONFIG_NF_CONNTRACK_TIMEOUT otherwise we can crash when dumping the policy if this option is not enabled. [ 71.600121] BUG: unable to handle kernel NULL pointer dereference at 0000000000000000 [...] [ 71.600141] CPU: 3 PID: 7612 Comm: nft Not tainted 4.18.0+ #246 [...] [ 71.600188] Call Trace: [ 71.600201] ? nft_ct_timeout_obj_dump+0xc6/0xf0 [nft_ct] Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-08-23netfilter: conntrack: remove duplicated include from nf_conntrack_proto_udp.cYue Haibing1-1/+0
Remove duplicated include. Fixes: c779e849608a ("netfilter: conntrack: remove get_timeout() indirection") Signed-off-by: Yue Haibing <yuehaibing@huawei.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-07-16netfilter: conntrack: remove get_timeout() indirectionFlorian Westphal1-7/+13
Not needed, we can have the l4trackers fetch it themselvs. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-07-16netfilter: conntrack: avoid l4proto pkt_to_tuple callsFlorian Westphal1-23/+0
Handle common protocols (udp, tcp, ..), in the core and only do the call if needed by the l4proto tracker. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-07-16netfilter: conntrack: avoid calls to l4proto invert_tupleFlorian Westphal1-12/+0
Handle the common cases (tcp, udp, etc). in the core and only do the indirect call for the protocols that need it (GRE for instance). Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-01-08netfilter: conntrack: timeouts can be constFlorian Westphal1-1/+1
Nowadays this is just the default template that is used when setting up the net namespace, so nothing writes to these locations. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-01-08netfilter: conntrack: l4 protocol trackers can be constFlorian Westphal1-4/+4
previous patches removed all writes to these structs so we can now mark them as const. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-10-24netfilter: conntrack: remove pf argument from l4 packet functionsFlorian Westphal1-1/+0
not needed/used anymore. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-10-24netfilter: conntrack: add and use nf_l4proto_log_invalidFlorian Westphal1-21/+19
We currently pass down the l4 protocol to the conntrack ->packet() function, but the only user of this is the debug info decision. Same information can be derived from struct nf_conn. As a first step, add and use a new log function for this, similar to nf_ct_helper_log(). Add __cold annotation -- invalid packets should be infrequent so gcc can consider all call paths that lead to such a function as unlikely. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-09-04netfilter: remove unused hooknum arg from packet functionsFlorian Westphal1-1/+0
tested with allmodconfig build. Signed-off-by: Florian Westphal <fw@strlen.de>
2017-08-24netfilter: conntrack: place print_tuple in procfs partFlorian Westphal1-13/+0
CONFIG_NF_CONNTRACK_PROCFS is deprecated, no need to use a function pointer in the trackers for this. Place the printf formatting in the one place that uses it. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-08-24netfilter: conntrack: remove protocol name from l4proto structFlorian Westphal1-4/+0
no need to waste storage for something that is only needed in one place and can be deduced from protocol number. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-02-02netfilter: conntrack: no need to pass ctinfo to error handlerFlorian Westphal1-2/+1
It is never accessed for reading and the only places that write to it are the icmp(6) handlers, which also set skb->nfct (and skb->nfctinfo). The conntrack core specifically checks for attached skb->nfct after ->error() invocation and returns early in this case. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-01-03netfilter: merge udp and udplite conntrack helpersFlorian Westphal1-0/+123
udplite was copied from udp, they are virtually 100% identical. This adds udplite tracker to udp instead, removes udplite module, and then makes the udplite tracker builtin. udplite will then simply re-use udp timeout settings. It makes little sense to add separate sysctls, nowadays we have fine-grained timeout policy support via the CT target. old: text data bss dec hex filename 1633 672 0 2305 901 nf_conntrack_proto_udp.o 1756 672 0 2428 97c nf_conntrack_proto_udplite.o 69526 17937 268 87731 156b3 nf_conntrack.ko new: text data bss dec hex filename 2442 1184 0 3626 e2a nf_conntrack_proto_udp.o 68565 17721 268 86554 1521a nf_conntrack.ko Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-13netfilter: remove ip_conntrack* sysctl compat codePablo Neira Ayuso1-48/+1
This backward compatibility has been around for more than ten years, since Yasuyuki Kozakai introduced IPv6 in conntrack. These days, we have alternate /proc/net/nf_conntrack* entries, the ctnetlink interface and the conntrack utility got adopted by many people in the user community according to what I observed on the netfilter user mailing list. So let's get rid of this. Note that nf_conntrack_htable_size and unsigned int nf_conntrack_max do not need to be exported as symbol anymore. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-12netfilter: conntrack: Only need first 4 bytes to get l4proto portsGao Feng1-2/+2
We only need first 4 bytes instead of 8 bytes to get the ports of tcp/udp/dccp/sctp/udplite in their pkt_to_tuple function. Signed-off-by: Gao Feng <fgao@ikuai8.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-05-05netfilter: conntrack: introduce clash resolution on insertion racePablo Neira Ayuso1-0/+2
This patch introduces nf_ct_resolve_clash() to resolve race condition on conntrack insertions. This is particularly a problem for connection-less protocols such as UDP, with no initial handshake. Two or more packets may race to insert the entry resulting in packet drops. Another problematic scenario are packets enqueued to userspace via NFQUEUE after the raw table, that make it easier to trigger this race. To resolve this, the idea is to reset the conntrack entry to the one that won race. Packet and bytes counters are also merged. The 'insert_failed' stats still accounts for this situation, after this patch, the drop counter is bumped whenever we drop packets, so we can watch for unresolved clashes. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-09-18netfilter: nf_conntrack: Add a struct net parameter to l4_pkt_to_tupleEric W. Biederman1-0/+1
As gre does not have the srckey in the packet gre_pkt_to_tuple needs to perform a lookup in it's per network namespace tables. Pass in the proper network namespace to all pkt_to_tuple implementations to ensure gre (and any similar protocols) can get this right. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-11-05netfilter: Convert print_tuple functions to return voidJoe Perches1-5/+5
Since adding a new function to seq_file (seq_has_overflowed()) there isn't any value for functions called from seq_show to return anything. Remove the int returns of the various print_tuple/<foo>_print_tuple functions. Link: http://lkml.kernel.org/p/f2e8cf8df433a197daa62cbaf124c900c708edc7.1412031505.git.joe@perches.com Cc: Pablo Neira Ayuso <pablo@netfilter.org> Cc: Patrick McHardy <kaber@trash.net> Cc: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu> Cc: netfilter-devel@vger.kernel.org Cc: coreteam@netfilter.org Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-04-18netfilter: add my copyright statementsPatrick McHardy1-0/+1
Add copyright statements to all netfilter files which have had significant changes done by myself in the past. Some notes: - nf_conntrack_ecache.c was incorrectly attributed to Rusty and Netfilter Core Team when it got split out of nf_conntrack_core.c. The copyrights even state a date which lies six years before it was written. It was written in 2005 by Harald and myself. - net/ipv{4,6}/netfilter.c, net/netfitler/nf_queue.c were missing copyright statements. I've added the copyright statement from net/netfilter/core.c, where this code originated - for nf_conntrack_proto_tcp.c I've also added Jozsef, since I didn't want it to give the wrong impression Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-04-05netfilter: nf_log: prepare net namespace support for loggersGao feng1-3/+3
This patch adds netns support to nf_log and it prepares netns support for existing loggers. It is composed of four major changes. 1) nf_log_register has been split to two functions: nf_log_register and nf_log_set. The new nf_log_register is used to globally register the nf_logger and nf_log_set is used for enabling pernet support from nf_loggers. Per netns is not yet complete after this patch, it comes in separate follow up patches. 2) Add net as a parameter of nf_log_bind_pf. Per netns is not yet complete after this patch, it only allows to bind the nf_logger to the protocol family from init_net and it skips other cases. 3) Adapt all nf_log_packet callers to pass netns as parameter. After this patch, this function only works for init_net. 4) Make the sysctl net/netfilter/nf_log pernet. Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-07-04netfilter: nf_conntrack: generalize nf_ct_l4proto_netPablo Neira Ayuso1-0/+7
This patch generalizes nf_ct_l4proto_net by splitting it into chunks and moving the corresponding protocol part to where it really belongs to. To clarify, note that we follow two different approaches to support per-net depending if it's built-in or run-time loadable protocol tracker. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Acked-by: Gao feng <gaofeng@cn.fujitsu.com>
2012-06-27netfilter: nf_ct_udp: merge udpv[4,6]_net_init into udp_net_initGao feng1-42/+23
Merge udpv4_net_init and udpv6_net_init into udp_net_init to remove redundant code now that we have the u_int16_t proto parameter. And use nf_proto_net.users to identify if it's the first time we use the nf_proto_net, in that case, we initialize it. Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-27netfilter: nf_conntrack: prepare l4proto->init_net cleanupGao feng1-2/+2
l4proto->init contain quite redundant code. We can simplify this by adding a new parameter l3proto. This patch prepares that code simplification. Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-11netfilter: nf_ct_tcp, udp: fix compilation with sysctl disabledPablo Neira Ayuso1-1/+1
This patch fixes the compilation of the TCP and UDP trackers with sysctl compilation disabled: net/netfilter/nf_conntrack_proto_udp.c: In function ‘udp_init_net_data’: net/netfilter/nf_conntrack_proto_udp.c:279:13: error: ‘struct nf_proto_net’ has no member named ‘user’ net/netfilter/nf_conntrack_proto_tcp.c:1606:9: error: ‘struct nf_proto_net’ has no member named ‘user’ net/netfilter/nf_conntrack_proto_tcp.c:1643:9: error: ‘struct nf_proto_net’ has no member named ‘user’ Reported-by: Fengguang Wu <wfg@linux.intel.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-07netfilter: nf_conntrack: add namespace support for cttimeoutGao feng1-3/+5
This patch adds namespace support for cttimeout. Acked-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-07netfilter: nf_conntrack: remove now unused sysctl for nf_conntrack_l[3|4]protoPablo Neira Ayuso1-15/+0
Since the sysctl data for l[3|4]proto now resides in pernet nf_proto_net. We can now remove this unused fields from struct nf_contrack_l[3,4]proto. Acked-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-07netfilter: nf_ct_udp: add namespace supportGao feng1-11/+89
This patch adds namespace support for UDP protocol tracker. Acked-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-04-01nf_conntrack_proto_udp{,lite}: Stop using NLA_PUT*().David S. Miller1-4/+5
These macros contain a hidden goto, and are thus extremely error prone and make code hard to audit. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-03-07netfilter: add cttimeout infrastructure for fine timeout tuningPablo Neira Ayuso1-0/+64
This patch adds the infrastructure to add fine timeout tuning over nfnetlink. Now you can use the NFNL_SUBSYS_CTNETLINK_TIMEOUT subsystem to create/delete/dump timeout objects that contain some specific timeout policy for one flow. The follow up patches will allow you attach timeout policy object to conntrack via the CT target and the conntrack extension infrastructure. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-03-07netfilter: nf_conntrack: pass timeout array to l4->new and l4->packetPablo Neira Ayuso1-4/+12
This patch defines a new interface for l4 protocol trackers: unsigned int *(*get_timeouts)(struct net *net); that is used to return the array of unsigned int that contains the timeouts that will be applied for this flow. This is passed to the l4proto->new(...) and l4proto->packet(...) functions to specify the timeout policy. This interface allows per-net global timeout configuration (although only DCCP supports this by now) and it will allow custom custom timeout configuration by means of follow-up patches. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-03-07netfilter: nf_ct_udp[lite]: convert UDP[lite] timeouts to arrayPablo Neira Ayuso1-10/+20
Use one array to store the UDP timeouts instead of two variables. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2011-12-16net:netfilter: use IS_ENABLEDIgor Maravić1-2/+2
Use IS_ENABLED(CONFIG_FOO) instead of defined(CONFIG_FOO) || defined (CONFIG_FOO_MODULE) Signed-off-by: Igor Maravić <igorm@etf.rs> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-02-15netfilter: nf_conntrack: pass template to l4proto ->error() handlerPatrick McHardy1-2/+2
The error handlers might need the template to get the conntrack zone introduced in the next patches to perform a conntrack lookup. Signed-off-by: Patrick McHardy <kaber@trash.net>
2010-02-03netfilter: nf_conntrack: split up IPCT_STATUS eventPatrick McHardy1-1/+1
Split up the IPCT_STATUS event into an IPCT_REPLY event, which is generated when the IPS_SEEN_REPLY bit is set, and an IPCT_ASSURED event, which is generated when the IPS_ASSURED bit is set. In combination with a following patch to support selective event delivery, this can be used for "sparse" conntrack replication: start replicating the conntrack entry after it reached the ASSURED state and that way it's SYN-flood resistant. Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-11-12sysctl net: Remove unused binary sysctl codeEric W. Biederman1-6/+2
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>
2009-03-25netfilter: nf_conntrack: calculate per-protocol nlattr sizeHolger Eitzenberger1-0/+2
Signed-off-by: Holger Eitzenberger <holger@eitzenberger.org> Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-03-16netfilter: remove IPvX specific parts from nf_conntrack_l4proto.hChristoph Paasch1-0/+2
Moving the structure definitions to the corresponding IPvX specific header files. Signed-off-by: Patrick McHardy <kaber@trash.net>
2008-11-03net: '&' reduxAlexey Dobriyan1-4/+4
I want to compile out proc_* and sysctl_* handlers totally and stub them to NULL depending on config options, however usage of & will prevent this, since taking adress of NULL pointer will break compilation. So, drop & in front of every ->proc_handler and every ->strategy handler, it was never needed in fact. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>