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2022-11-17sctp: move SCTP_PAD4 and SCTP_TRUNC4 to linux/sctp.hXin Long1-1/+0
Move these two macros from net/sctp/sctp.h to linux/sctp.h, so that it will be enough to include only linux/sctp.h in nft_exthdr.c and xt_sctp.c. It should not include "net/sctp/sctp.h" if a module does not have a dependence on SCTP module. Signed-off-by: Xin Long <lucien.xin@gmail.com> Reviewed-by: Saeed Mahameed <saeed@kernel.org> Link: https://lore.kernel.org/r/ef6468a687f36da06f575c2131cd4612f6b7be88.1668526821.git.lucien.xin@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-15netfilter: nf_tables: Extend nft_expr_ops::dump callback parametersPhil Sutter1-3/+6
Add a 'reset' flag just like with nft_object_ops::dump. This will be useful to reset "anonymous stateful objects", e.g. simple rule counters. No functional change intended. Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-07-11netfilter: nf_tables: use correct integer typesFlorian Westphal1-5/+5
Sparse tool complains about mixing of different endianess types, so use the correct ones. Add type casts where needed. objdiff shows no changes except in nft_tunnel (type is changed). Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-03-20netfilter: nft_exthdr: add reduce supportFlorian Westphal1-0/+33
Check if we can elide the load. Cancel if the new candidate isn't identical to previous store. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-02-10Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-1/+1
No conflicts. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-04netfilter: exthdr: add support for tcp option removalFlorian Westphal1-1/+95
This allows to replace a tcp option with nop padding to selectively disable a particular tcp option. Optstrip mode is chosen when userspace passes the exthdr expression with neither a source nor a destination register attribute. This is identical to xtables TCPOPTSTRIP extension. The only difference is that TCPOPTSTRIP allows to pass in a bitmap of options to remove rather than a single number. Unlike TCPOPTSTRIP this expression can be used multiple times in the same rule to get the same effect. We could add a new nested attribute later on in case there is a use case for single-expression-multi-remove. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-02-04netfilter: nft_payload: don't allow th access for fragmentsFlorian Westphal1-1/+1
Loads relative to ->thoff naturally expect that this points to the transport header, but this is only true if pkt->fragoff == 0. This has little effect for rulesets with connection tracking/nat because these enable ip defra. For other rulesets this prevents false matches. Fixes: 96518518cc41 ("netfilter: add nftables") Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-12-08netfilter: nft_exthdr: break evaluation if setting TCP option failsPablo Neira Ayuso1-4/+7
Break rule evaluation on malformed TCP options. Fixes: 99d1712bc41c ("netfilter: exthdr: tcp option set support") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-06-29Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-0/+3
Trivial conflict in net/netfilter/nf_tables_api.c. Duplicate fix in tools/testing/selftests/net/devlink_port_split.py - take the net-next version. skmsg, and L4 bpf - keep the bpf code but remove the flags and err params. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-06-16netfilter: nft_extdhr: Drop pointless check of tprot_setPhil Sutter1-1/+1
Pablo says, tprot_set is only there to detect if tprot was set to IPPROTO_IP as that evaluates to zero. Therefore, code asserting a different value in tprot does not need to check tprot_set. Fixes: 935b7f6430188 ("netfilter: nft_exthdr: add TCP option matching") Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-06-16netfilter: nft_exthdr: Search chunks in SCTP packets onlyPhil Sutter1-1/+4
Since user space does not generate a payload dependency, plain sctp chunk matches cause searching in non-SCTP packets, too. Avoid this potential mis-interpretation of packet data by checking pkt->tprot. Fixes: 133dc203d77df ("netfilter: nft_exthdr: Support SCTP chunks") Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-06-16netfilter: nft_exthdr: check for IPv6 packet before further processingPablo Neira Ayuso1-0/+3
ipv6_find_hdr() does not validate that this is an IPv6 packet. Add a sanity check for calling ipv6_find_hdr() to make sure an IPv6 packet is passed for parsing. Fixes: 96518518cc41 ("netfilter: add nftables") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-06-09netfilter: nft_exthdr: Fix for unsafe packet data readPhil Sutter1-1/+3
While iterating through an SCTP packet's chunks, skb_header_pointer() is called for the minimum expected chunk header size. If (that part of) the skbuff is non-linear, the following memcpy() may read data past temporary buffer '_sch'. Use skb_copy_bits() instead which does the right thing in this situation. Fixes: 133dc203d77df ("netfilter: nft_exthdr: Support SCTP chunks") Suggested-by: Florian Westphal <fw@strlen.de> Signed-off-by: Phil Sutter <phil@nwl.cc> Reviewed-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-05-29netfilter: nf_tables: add and use nft_thoff helperFlorian Westphal1-4/+4
This allows to change storage placement later on without changing readers. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-05-28netfilter: nft_exthdr: Support SCTP chunksPhil Sutter1-0/+51
Chunks are SCTP header extensions similar in implementation to IPv6 extension headers or TCP options. Reusing exthdr expression to find and extract field values from them is therefore pretty straightforward. For now, this supports extracting data from chunks at a fixed offset (and length) only - chunks themselves are an extensible data structure; in order to make all fields available, a nested extension search is needed. Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-01-27netfilter: nftables: add nft_parse_register_store() and use itPablo Neira Ayuso1-4/+4
This new function combines the netlink register attribute parser and the store validation function. This update requires to replace: enum nft_registers dreg:8; in many of the expression private areas otherwise compiler complains with: error: cannot take address of bit-field ‘dreg’ when passing the register field as reference. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-01-27netfilter: nftables: add nft_parse_register_load() and use itPablo Neira Ayuso1-3/+3
This new function combines the netlink register attribute parser and the load validation function. This update requires to replace: enum nft_registers sreg:8; in many of the expression private areas otherwise compiler complains with: error: cannot take address of bit-field ‘sreg’ when passing the register field as reference. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-08-10netfilter: nf_tables: nft_exthdr: the presence return value should be ↵Stephen Suryaputra1-2/+2
little-endian On big-endian machine, the returned register data when the exthdr is present is not being compared correctly because little-endian is assumed. The function nft_cmp_fast_mask(), called by nft_cmp_fast_eval() and nft_cmp_fast_init(), calls cpu_to_le32(). The following dump also shows that little endian is assumed: $ nft --debug=netlink add rule ip recordroute forward ip option rr exists counter ip [ exthdr load ipv4 1b @ 7 + 0 present => reg 1 ] [ cmp eq reg 1 0x01000000 ] [ counter pkts 0 bytes 0 ] Lastly, debug print in nft_cmp_fast_init() and nft_cmp_fast_eval() when RR option exists in the packet shows that the comparison fails because the assumption: nft_cmp_fast_init:189 priv->sreg=4 desc.len=8 mask=0xff000000 data.data[0]=0x10003e0 nft_cmp_fast_eval:57 regs->data[priv->sreg=4]=0x1 mask=0xff000000 priv->data=0x1000000 v2: use nft_reg_store8() instead (Florian Westphal). Also to avoid the warnings reported by kernel test robot. Fixes: dbb5281a1f84 ("netfilter: nf_tables: add support for matching IPv4 options") Fixes: c078ca3b0c5b ("netfilter: nft_exthdr: Add support for existence check") Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-03-30netfilter: nft_exthdr: fix endianness of tcp option castSergey Marinkevich1-5/+3
I got a problem on MIPS with Big-Endian is turned on: every time when NF trying to change TCP MSS it returns because of new.v16 was greater than old.v16. But real MSS was 1460 and my rule was like this: add rule table chain tcp option maxseg size set 1400 And 1400 is lesser that 1460, not greater. Later I founded that main causer is cast from u32 to __be16. Debugging: In example MSS = 1400(HEX: 0x578). Here is representation of each byte like it is in memory by addresses from left to right(e.g. [0x0 0x1 0x2 0x3]). LE — Little-Endian system, BE — Big-Endian, left column is type. LE BE u32: [78 05 00 00] [00 00 05 78] As you can see, u32 representation will be casted to u16 from different half of 4-byte address range. But actually nf_tables uses registers and store data of various size. Actually TCP MSS stored in 2 bytes. But registers are still u32 in definition: struct nft_regs { union { u32 data[20]; struct nft_verdict verdict; }; }; So, access like regs->data[priv->sreg] exactly u32. So, according to table presents above, per-byte representation of stored TCP MSS in register will be: LE BE (u32)regs->data[]: [78 05 00 00] [05 78 00 00] ^^ ^^ We see that register uses just half of u32 and other 2 bytes may be used for some another data. But in nft_exthdr_tcp_set_eval() it casted just like u32 -> __be16: new.v16 = src But u32 overfill __be16, so it get 2 low bytes. For clarity draw one more table(<xx xx> means that bytes will be used for cast). LE BE u32: [<78 05> 00 00] [00 00 <05 78>] (u32)regs->data[]: [<78 05> 00 00] [05 78 <00 00>] As you can see, for Little-Endian nothing changes, but for Big-endian we take the wrong half. In my case there is some other data instead of zeros, so new MSS was wrongly greater. For shooting this bug I used solution for ports ranges. Applying of this patch does not affect Little-Endian systems. Signed-off-by: Sergey Marinkevich <sergey.marinkevich@eltex-co.ru> Acked-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-06-25Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextPablo Neira Ayuso1-4/+1
Resolve conflict between d2912cb15bdd ("treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500") removing the GPL disclaimer and fe03d4745675 ("Update my email address") which updates Jozsef Kadlecsik's email. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-06-22Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-4/+1
Minor SPDX change conflict. Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-21netfilter: nf_tables: add support for matching IPv4 optionsStephen Suryaputra1-0/+133
This is the kernel change for the overall changes with this description: Add capability to have rules matching IPv4 options. This is developed mainly to support dropping of IP packets with loose and/or strict source route route options. Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500Thomas Gleixner1-4/+1
Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-31netfilter: nf_tables: prefer skb_ensure_writableFlorian Westphal1-1/+2
.. so skb_make_writable can be removed. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-04-27netfilter: nf_tables: merge exthdr expression into nft coreFlorian Westphal1-21/+2
before: text data bss dec hex filename 5056 844 0 5900 170c net/netfilter/nft_exthdr.ko 102456 2316 401 105173 19ad5 net/netfilter/nf_tables.ko after: 106410 2392 401 109203 1aa93 net/netfilter/nf_tables.ko Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-12-11netfilter: exthdr: add missign attributes to policyFlorian Westphal1-0/+2
Add missing netlink attribute policy. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-08-28netfilter: fix a few (harmless) sparse warningsFlorian Westphal1-1/+1
net/netfilter/nft_payload.c:187:18: warning: incorrect type in return expression (expected bool got restricted __sum16 [usertype] check) net/netfilter/nft_exthdr.c:222:14: warning: cast to restricted __be32 net/netfilter/nft_rt.c:49:23: warning: incorrect type in assignment (different base types expected unsigned int got restricted __be32) net/netfilter/nft_rt.c:70:25: warning: symbol 'nft_rt_policy' was not declared. Should it be static? Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-08-19netfilter: exthdr: tcp option set supportFlorian Westphal1-2/+162
This allows setting 2 and 4 byte quantities in the tcp option space. Main purpose is to allow native replacement for xt_TCPMSS to work around pmtu blackholes. Writes to kind and len are now allowed at the moment, it does not seem useful to do this as it causes corruption of the tcp option space. We can always lift this restriction later if a use-case appears. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-08-19netfilter: exthdr: split netlink dump functionFlorian Westphal1-5/+11
so eval and uncoming eval_set versions can reuse a common helper. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-08-19netfilter: exthdr: factor out tcp option accessFlorian Westphal1-12/+21
Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-07netfilter: Remove exceptional & on function nameArushi Singhal1-1/+1
Remove & from function pointers to conform to the style found elsewhere in the file. Done using the following semantic patch // <smpl> @r@ identifier f; @@ f(...) { ... } @@ identifier r.f; @@ - &f + f // </smpl> Signed-off-by: Arushi Singhal <arushisinghal19971997@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-03-06netfilter: nft_exthdr: Allow checking TCP option presence, tooPhil Sutter1-3/+10
Honor NFT_EXTHDR_F_PRESENT flag so we check if the TCP option is present. Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-02-08netfilter: nft_exthdr: add TCP option matchingManuel Messner1-13/+106
This patch implements the kernel side of the TCP option patch. Signed-off-by: Manuel Messner <mm@skelett.io> Reviewed-by: Florian Westphal <fw@strlen.de> Acked-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-02-08netfilter: nft_exthdr: Add support for existence checkPhil Sutter1-2/+20
If NFT_EXTHDR_F_PRESENT is set, exthdr will not copy any header field data into *dest, but instead set it to 1 if the header is found and 0 otherwise. Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-10-17netfilter: nft_exthdr: fix error handling in nft_exthdr_init()Dan Carpenter1-1/+2
"err" needs to be signed for the error handling to work. Fixes: 36b701fae12a ('netfilter: nf_tables: validate maximum value of u32 netlink attributes') Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-09-23netfilter: nf_tables: validate maximum value of u32 netlink attributesLaura Garcia Liebana1-5/+7
Fetch value and validate u32 netlink attribute. This validation is usually required when the u32 netlink attributes are being stored in a field whose size is smaller. This patch revisits 4da449ae1df9 ("netfilter: nft_exthdr: Add size check on u8 nft_exthdr attributes"). Fixes: 96518518cc41 ("netfilter: add nftables") Suggested-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Laura Garcia Liebana <nevola@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-10netfilter: nft_exthdr: Add size check on u8 nft_exthdr attributesLaura Garcia Liebana1-2/+9
Fix the direct assignment of offset and length attributes included in nft_exthdr structure from u32 data to u8. Signed-off-by: Laura Garcia Liebana <nevola@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-04-13netfilter: nf_tables: switch registers to 32 bit addressingPatrick McHardy1-1/+2
Switch the nf_tables registers from 128 bit addressing to 32 bit addressing to support so called concatenations, where multiple values can be concatenated over multiple registers for O(1) exact matches of multiple dimensions using sets. The old register values are mapped to areas of 128 bits for compatibility. When dumping register numbers, values are expressed using the old values if they refer to the beginning of a 128 bit area for compatibility. To support concatenations, register loads of less than a full 32 bit value need to be padded. This mainly affects the payload and exthdr expressions, which both unconditionally zero the last word before copying the data. Userspace fully passes the testsuite using both old and new register addressing. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-04-13netfilter: nf_tables: add register parsing/dumping helpersPatrick McHardy1-2/+2
Add helper functions to parse and dump register values in netlink attributes. These helpers will later be changed to take care of translation between the old 128 bit and the new 32 bit register numbers. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-04-13netfilter: nf_tables: convert expressions to u32 register pointersPatrick McHardy1-2/+2
Simple conversion to use u32 pointers to the beginning of the registers to keep follow up patches smaller. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-04-13netfilter: nf_tables: get rid of NFT_REG_VERDICT usagePatrick McHardy1-3/+3
Replace the array of registers passed to expressions by a struct nft_regs, containing the verdict as a seperate member, which aliases to the NFT_REG_VERDICT register. This is needed to seperate the verdict from the data registers completely, so their size can be changed. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-04-13netfilter: nf_tables: kill nft_validate_output_register()Patrick McHardy1-5/+1
All users of nft_validate_register_store() first invoke nft_validate_output_register(). There is in fact no use for using it on its own, so simplify the code by folding the functionality into nft_validate_register_store() and kill it. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-04-13netfilter: nf_tables: rename nft_validate_data_load()Patrick McHardy1-2/+2
The existing name is ambiguous, data is loaded as well when we read from a register. Rename to nft_validate_register_store() for clarity and consistency with the upcoming patch to introduce its counterpart, nft_validate_register_load(). Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-04-13netfilter: nf_tables: validate len in nft_validate_data_load()Patrick McHardy1-4/+2
For values spanning multiple registers, we need to validate that enough space is available from the destination register onwards. Add a len argument to nft_validate_data_load() and consolidate the existing length validations in preparation of that. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-12-20netfilter: nft_exthdr: call ipv6_find_hdr() with explicitly initialized offsetDaniel Borkmann1-1/+1
In nft's nft_exthdr_eval() routine we process IPv6 extension header through invoking ipv6_find_hdr(), but we call it with an uninitialized offset variable that contains some stack value. In ipv6_find_hdr() we then test if the value of offset != 0 and call skb_header_pointer() on that offset in order to map struct ipv6hdr into it. Fix it up by initializing offset to 0 as it was probably intended to be. Fixes: 96518518cc41 ("netfilter: add nftables") Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Cc: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-10-14netfilter: nf_tables: expression ops overloadingPatrick McHardy1-5/+11
Split the expression ops into two parts and support overloading of the runtime expression ops based on the requested function through a ->select_ops() callback. This can be used to provide optimized implementations, for instance for loading small aligned amounts of data from the packet or inlining frequently used operations into the main evaluation loop. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-10-14netfilter: add nftablesPatrick McHardy1-0/+127
This patch adds nftables which is the intended successor of iptables. This packet filtering framework reuses the existing netfilter hooks, the connection tracking system, the NAT subsystem, the transparent proxying engine, the logging infrastructure and the userspace packet queueing facilities. In a nutshell, nftables provides a pseudo-state machine with 4 general purpose registers of 128 bits and 1 specific purpose register to store verdicts. This pseudo-machine comes with an extensible instruction set, a.k.a. "expressions" in the nftables jargon. The expressions included in this patch provide the basic functionality, they are: * bitwise: to perform bitwise operations. * byteorder: to change from host/network endianess. * cmp: to compare data with the content of the registers. * counter: to enable counters on rules. * ct: to store conntrack keys into register. * exthdr: to match IPv6 extension headers. * immediate: to load data into registers. * limit: to limit matching based on packet rate. * log: to log packets. * meta: to match metainformation that usually comes with the skbuff. * nat: to perform Network Address Translation. * payload: to fetch data from the packet payload and store it into registers. * reject (IPv4 only): to explicitly close connection, eg. TCP RST. Using this instruction-set, the userspace utility 'nft' can transform the rules expressed in human-readable text representation (using a new syntax, inspired by tcpdump) to nftables bytecode. nftables also inherits the table, chain and rule objects from iptables, but in a more configurable way, and it also includes the original datatype-agnostic set infrastructure with mapping support. This set infrastructure is enhanced in the follow up patch (netfilter: nf_tables: add netlink set API). This patch includes the following components: * the netlink API: net/netfilter/nf_tables_api.c and include/uapi/netfilter/nf_tables.h * the packet filter core: net/netfilter/nf_tables_core.c * the expressions (described above): net/netfilter/nft_*.c * the filter tables: arp, IPv4, IPv6 and bridge: net/ipv4/netfilter/nf_tables_ipv4.c net/ipv6/netfilter/nf_tables_ipv6.c net/ipv4/netfilter/nf_tables_arp.c net/bridge/netfilter/nf_tables_bridge.c * the NAT table (IPv4 only): net/ipv4/netfilter/nf_table_nat_ipv4.c * the route table (similar to mangle): net/ipv4/netfilter/nf_table_route_ipv4.c net/ipv6/netfilter/nf_table_route_ipv6.c * internal definitions under: include/net/netfilter/nf_tables.h include/net/netfilter/nf_tables_core.h * It also includes an skeleton expression: net/netfilter/nft_expr_template.c and the preliminary implementation of the meta target net/netfilter/nft_meta_target.c It also includes a change in struct nf_hook_ops to add a new pointer to store private data to the hook, that is used to store the rule list per chain. This patch is based on the patch from Patrick McHardy, plus merged accumulated cleanups, fixes and small enhancements to the nftables code that has been done since 2009, which are: From Patrick McHardy: * nf_tables: adjust netlink handler function signatures * nf_tables: only retry table lookup after successful table module load * nf_tables: fix event notification echo and avoid unnecessary messages * nft_ct: add l3proto support * nf_tables: pass expression context to nft_validate_data_load() * nf_tables: remove redundant definition * nft_ct: fix maxattr initialization * nf_tables: fix invalid event type in nf_tables_getrule() * nf_tables: simplify nft_data_init() usage * nf_tables: build in more core modules * nf_tables: fix double lookup expression unregistation * nf_tables: move expression initialization to nf_tables_core.c * nf_tables: build in payload module * nf_tables: use NFPROTO constants * nf_tables: rename pid variables to portid * nf_tables: save 48 bits per rule * nf_tables: introduce chain rename * nf_tables: check for duplicate names on chain rename * nf_tables: remove ability to specify handles for new rules * nf_tables: return error for rule change request * nf_tables: return error for NLM_F_REPLACE without rule handle * nf_tables: include NLM_F_APPEND/NLM_F_REPLACE flags in rule notification * nf_tables: fix NLM_F_MULTI usage in netlink notifications * nf_tables: include NLM_F_APPEND in rule dumps From Pablo Neira Ayuso: * nf_tables: fix stack overflow in nf_tables_newrule * nf_tables: nft_ct: fix compilation warning * nf_tables: nft_ct: fix crash with invalid packets * nft_log: group and qthreshold are 2^16 * nf_tables: nft_meta: fix socket uid,gid handling * nft_counter: allow to restore counters * nf_tables: fix module autoload * nf_tables: allow to remove all rules placed in one chain * nf_tables: use 64-bits rule handle instead of 16-bits * nf_tables: fix chain after rule deletion * nf_tables: improve deletion performance * nf_tables: add missing code in route chain type * nf_tables: rise maximum number of expressions from 12 to 128 * nf_tables: don't delete table if in use * nf_tables: fix basechain release From Tomasz Bursztyka: * nf_tables: Add support for changing users chain's name * nf_tables: Change chain's name to be fixed sized * nf_tables: Add support for replacing a rule by another one * nf_tables: Update uapi nftables netlink header documentation From Florian Westphal: * nft_log: group is u16, snaplen u32 From Phil Oester: * nf_tables: operational limit match Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>