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* crypto: remove CONFIG_CRYPTO_STATSEric Biggers2024-04-021-50/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove support for the "Crypto usage statistics" feature (CONFIG_CRYPTO_STATS). This feature does not appear to have ever been used, and it is harmful because it significantly reduces performance and is a large maintenance burden. Covering each of these points in detail: 1. Feature is not being used Since these generic crypto statistics are only readable using netlink, it's fairly straightforward to look for programs that use them. I'm unable to find any evidence that any such programs exist. For example, Debian Code Search returns no hits except the kernel header and kernel code itself and translations of the kernel header: https://codesearch.debian.net/search?q=CRYPTOCFGA_STAT&literal=1&perpkg=1 The patch series that added this feature in 2018 (https://lore.kernel.org/linux-crypto/1537351855-16618-1-git-send-email-clabbe@baylibre.com/) said "The goal is to have an ifconfig for crypto device." This doesn't appear to have happened. It's not clear that there is real demand for crypto statistics. Just because the kernel provides other types of statistics such as I/O and networking statistics and some people find those useful does not mean that crypto statistics are useful too. Further evidence that programs are not using CONFIG_CRYPTO_STATS is that it was able to be disabled in RHEL and Fedora as a bug fix (https://gitlab.com/redhat/centos-stream/src/kernel/centos-stream-9/-/merge_requests/2947). Even further evidence comes from the fact that there are and have been bugs in how the stats work, but they were never reported. For example, before Linux v6.7 hash stats were double-counted in most cases. There has also never been any documentation for this feature, so it might be hard to use even if someone wanted to. 2. CONFIG_CRYPTO_STATS significantly reduces performance Enabling CONFIG_CRYPTO_STATS significantly reduces the performance of the crypto API, even if no program ever retrieves the statistics. This primarily affects systems with a large number of CPUs. For example, https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2039576 reported that Lustre client encryption performance improved from 21.7GB/s to 48.2GB/s by disabling CONFIG_CRYPTO_STATS. It can be argued that this means that CONFIG_CRYPTO_STATS should be optimized with per-cpu counters similar to many of the networking counters. But no one has done this in 5+ years. This is consistent with the fact that the feature appears to be unused, so there seems to be little interest in improving it as opposed to just disabling it. It can be argued that because CONFIG_CRYPTO_STATS is off by default, performance doesn't matter. But Linux distros tend to error on the side of enabling options. The option is enabled in Ubuntu and Arch Linux, and until recently was enabled in RHEL and Fedora (see above). So, even just having the option available is harmful to users. 3. CONFIG_CRYPTO_STATS is a large maintenance burden There are over 1000 lines of code associated with CONFIG_CRYPTO_STATS, spread among 32 files. It significantly complicates much of the implementation of the crypto API. After the initial submission, many fixes and refactorings have consumed effort of multiple people to keep this feature "working". We should be spending this effort elsewhere. Acked-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Corentin Labbe <clabbe@baylibre.com> Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: rng - Count error stats differentlyHerbert Xu2023-03-141-8/+57
| | | | | | | | | | | | | | | | Move all stat code specific to rng into the rng code. While we're at it, change the stats so that bytes and counts are always incremented even in case of error. This allows the reference counting to be removed as we can now increment the counters prior to the operation. After the operation we simply increase the error count if necessary. This is safe as errors can only occur synchronously (or rather, the existing code already ignored asynchronous errors which are only visible to the callback function). Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: api - check for ERR pointers in crypto_destroy_tfm()Ard Biesheuvel2021-03-121-0/+2
| | | | | | | | | | | | | | | Given that crypto_alloc_tfm() may return ERR pointers, and to avoid crashes on obscure error paths where such pointers are presented to crypto_destroy_tfm() (such as [0]), add an ERR_PTR check there before dereferencing the second argument as a struct crypto_tfm pointer. [0] https://lore.kernel.org/linux-crypto/000000000000de949705bc59e0f6@google.com/ Reported-by: syzbot+12cf5fbfdeba210a89dd@syzkaller.appspotmail.com Reviewed-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152Thomas Gleixner2019-05-301-6/+1
| | | | | | | | | | | | | | | | | | | | | Based on 1 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 as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* crypto: user - fix use_after_free of struct xxx_requestCorentin Labbe2018-12-071-24/+3
| | | | | | | | | | | | | All crypto_stats functions use the struct xxx_request for feeding stats, but in some case this structure could already be freed. For fixing this, the needed parameters (len and alg) will be stored before the request being executed. Fixes: cac5818c25d0 ("crypto: user - Implement a generic crypto statistics") Reported-by: syzbot <syzbot+6939a606a5305e9e9799@syzkaller.appspotmail.com> Signed-off-by: Corentin Labbe <clabbe@baylibre.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: user - convert all stats from u32 to u64Corentin Labbe2018-12-071-4/+4
| | | | | | | | | All the 32-bit fields need to be 64-bit. In some cases, UINT32_MAX crypto operations can be done in seconds. Reported-by: Eric Biggers <ebiggers@kernel.org> Signed-off-by: Corentin Labbe <clabbe@baylibre.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: user - Implement a generic crypto statisticsCorentin Labbe2018-09-281-1/+28
| | | | | | | | This patch implement a generic way to get statistics about all crypto usages. Signed-off-by: Corentin Labbe <clabbe@baylibre.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: doc - Fix typo in crypto-API.xmlMasanari Iida2015-06-041-1/+1
| | | | | | | | | | This patch fix some typos found in crypto-API.xml. It is because the file is generated from comments in sources, so I had to fix typo in sources. Signed-off-by: Masanari Iida <standby24x7@gmail.com> Acked-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: rng - Remove old low-level rng interfaceHerbert Xu2015-04-221-7/+3
| | | | | | | Now that all rng implementations have switched over to the new interface, we can remove the old low-level interface. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: rng - Add crypto_rng_set_entropyHerbert Xu2015-04-221-0/+4
| | | | | | | | This patch adds the function crypto_rng_set_entropy. It is only meant to be used by testmgr when testing RNG implementations by providing fixed entropy data in order to verify test vectors. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: rng - Convert low-level crypto_rng to new styleHerbert Xu2015-04-221-2/+40
| | | | | | | | | | | This patch converts the low-level crypto_rng interface to the "new" style. This allows existing implementations to be converted over one- by-one. Once that is complete we can then remove the old rng interface. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: rng - Mark crypto_rng_reset seed as constHerbert Xu2015-04-221-6/+3
| | | | | | | | | There is no reason why crypto_rng_reset should modify the seed so this patch marks it as const. Since our algorithms don't export a const seed function yet we have to go through some contortions for now. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: rng - Introduce crypto_rng_generateHerbert Xu2015-04-211-2/+25
| | | | | | | | | This patch adds the new top-level function crypto_rng_generate which generates random numbers with additional input. It also extends the mid-level rng_gen_random function to take additional data as input. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: rng - Convert crypto_rng to new style crypto_typeHerbert Xu2015-04-211-22/+10
| | | | | | | | | | | | | This patch converts the top-level crypto_rng to the "new" style. It was the last algorithm type added before we switched over to the new way of doing things exemplified by shash. All users will automatically switch over to the new interface. Note that this patch does not touch the low-level interface to rng implementations. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: rng - RNGs must return 0 in success caseStephan Mueller2015-03-091-2/+1
| | | | | | | | | | | | Change the RNGs to always return 0 in success case. This patch ensures that seqiv.c works with RNGs other than krng. seqiv expects that any return code other than 0 is an error. Without the patch, rfc4106(gcm(aes)) will not work when using a DRBG or an ANSI X9.31 RNG. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: doc - RNG API documentationStephan Mueller2014-11-131-0/+80
| | | | | | | | The API function calls exported by the kernel crypto API for RNGs to be used by consumers are documented. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: rng - RNG interface and implementationNeil Horman2008-08-291-0/+75
This patch adds a random number generator interface as well as a cryptographic pseudo-random number generator based on AES. It is meant to be used in cases where a deterministic CPRNG is required. One of the first applications will be as an input in the IPsec IV generation process. Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>