linux-dev/include/linux/netfilter_bridge, branch linus/master

netfilter: ebtables: allow use of ebt_do_table as hookfn

2021-10-14T21:06:53Z

This is possible now that the xt_table structure is passed via *priv. Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso

netfilter: ebtables: do not hook tables by default

2021-08-02T09:40:45Z

If any of these modules is loaded, hooks get registered in all netns: Before: 'unshare -n nft list hooks' shows: family bridge hook prerouting { -2147483648 ebt_broute -0000000300 ebt_nat_hook } family bridge hook input { -0000000200 ebt_filter_hook } family bridge hook forward { -0000000200 ebt_filter_hook } family bridge hook output { +0000000100 ebt_nat_hook +0000000200 ebt_filter_hook } family bridge hook postrouting { +0000000300 ebt_nat_hook } This adds 'template 'tables' for ebtables. Each ebtable_foo registers the table as a template, with an init function that gets called once the first get/setsockopt call is made. ebtables core then searches the (per netns) list of tables. If no table is found, it searches the list of templates instead. If a template entry exists, the init function is called which will enable the table and register the hooks (so packets are diverted to the table). If no entry is found in the template list, request_module is called. After this, hook registration is delayed until the 'ebtables' (set/getsockopt) request is made for a given table and will only happen in the specific namespace. Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso

netfilter: ebtables: remove the 3 ebtables pointers from struct net

2021-04-26T01:20:07Z

ebtables stores the table internal data (what gets passed to the ebt_do_table() interpreter) in struct net. nftables keeps the internal interpreter format in pernet lists and passes it via the netfilter core infrastructure (priv pointer). Do the same for ebtables: the nf_hook_ops are duplicated via kmemdup, then the ops->priv pointer is set to the table that is being registered. After that, the netfilter core passes this table info to the hookfn. This allows to remove the pointers from struct net. Same pattern can be applied to ip/ip6/arptables. Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso

netfilter: bridge: add pre_exit hooks for ebtable unregistration

2021-04-10T19:16:54Z

Just like ip/ip6/arptables, the hooks have to be removed, then synchronize_rcu() has to be called to make sure no more packets are being processed before the ruleset data is released. Place the hook unregistration in the pre_exit hook, then call the new ebtables pre_exit function from there. Years ago, when first netns support got added for netfilter+ebtables, this used an older (now removed) netfilter hook unregister API, that did a unconditional synchronize_rcu(). Now that all is done with call_rcu, ebtable_{filter,nat,broute} pernet exit handlers may free the ebtable ruleset while packets are still in flight. This can only happens on module removal, not during netns exit. The new function expects the table name, not the table struct. This is because upcoming patch set (targeting -next) will remove all net->xt.{nat,filter,broute}_table instances, this makes it necessary to avoid external references to those member variables. The existing APIs will be converted, so follow the upcoming scheme of passing name + hook type instead. Fixes: aee12a0a3727e ("ebtables: remove nf_hook_register usage") Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso

netfilter: Replace zero-length array with flexible-array member

2020-03-15T14:20:16Z

The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] Lastly, fix checkpatch.pl warning WARNING: __aligned(size) is preferred over __attribute__((aligned(size))) in net/bridge/netfilter/ebtables.c This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva Signed-off-by: Pablo Neira Ayuso

netfilter: remove CONFIG_NETFILTER checks from headers.

2019-09-13T10:47:36Z

`struct nf_hook_ops`, `struct nf_hook_state` and the `nf_hookfn` function typedef appear in function and struct declarations and definitions in a number of netfilter headers. The structs and typedef themselves are defined by linux/netfilter.h but only when CONFIG_NETFILTER is enabled. Define them unconditionally and add forward declarations in order to remove CONFIG_NETFILTER conditionals from the other headers. Signed-off-by: Jeremy Sowden Signed-off-by: Pablo Neira Ayuso

netfilter: inline xt_hashlimit, ebt_802_3 and xt_physdev headers

2019-09-13T10:32:48Z

Three netfilter headers are only included once. Inline their contents at those sites and remove them. Signed-off-by: Jeremy Sowden Signed-off-by: Pablo Neira Ayuso

netfilter: add missing IS_ENABLED(CONFIG_NETFILTER) checks to some header-files.

2019-08-13T10:15:18Z

linux/netfilter.h defines a number of struct and inline function definitions which are only available is CONFIG_NETFILTER is enabled. These structs and functions are used in declarations and definitions in other header-files. Added preprocessor checks to make sure these headers will compile if CONFIG_NETFILTER is disabled. Signed-off-by: Jeremy Sowden Signed-off-by: Pablo Neira Ayuso

netfilter: ebtables: remove EBT_MATCH and EBT_NOMATCH

2018-04-24T08:29:16Z

EBT_MATCH and EBT_NOMATCH are used to change return value. match functions(ebt_xxx.c) return false when received frame is not matched and returns true when received frame is matched. but, EBT_MATCH_ITERATE understands oppositely. so, to change return value, EBT_MATCH and EBT_NOMATCH are used. but, we can use operation '!' simply. Signed-off-by: Taehee Yoo Signed-off-by: Pablo Neira Ayuso

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02T10:10:55Z

Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman