kernel/linux.git/crypto/authenc.c, branch v6.1.168

crypto: authenc - Fix sleep in atomic context in decrypt_tail

2022-01-31T00:21:44+00:00

The function crypto_authenc_decrypt_tail discards its flags argument and always relies on the flags from the original request when starting its sub-request. This is clearly wrong as it may cause the SLEEPABLE flag to be set when it shouldn't. Fixes: 92d95ba91772 ("crypto: authenc - Convert to new AEAD interface") Reported-by: Corentin Labbe Signed-off-by: Herbert Xu Tested-by: Corentin Labbe Signed-off-by: Herbert Xu

crypto: algapi - use common mechanism for inheriting flags

2020-07-16T11:49:08+00:00

The flag CRYPTO_ALG_ASYNC is "inherited" in the sense that when a template is instantiated, the template will have CRYPTO_ALG_ASYNC set if any of the algorithms it uses has CRYPTO_ALG_ASYNC set. We'd like to add a second flag (CRYPTO_ALG_ALLOCATES_MEMORY) that gets "inherited" in the same way. This is difficult because the handling of CRYPTO_ALG_ASYNC is hardcoded everywhere. Address this by: - Add CRYPTO_ALG_INHERITED_FLAGS, which contains the set of flags that have these inheritance semantics. - Add crypto_algt_inherited_mask(), for use by template ->create() methods. It returns any of these flags that the user asked to be unset and thus must be passed in the 'mask' to crypto_grab_*(). - Also modify crypto_check_attr_type() to handle computing the 'mask' so that most templates can just use this. - Make crypto_grab_*() propagate these flags to the template instance being created so that templates don't have to do this themselves. Make crypto/simd.c propagate these flags too, since it "wraps" another algorithm, similar to a template. Based on a patch by Mikulas Patocka (https://lore.kernel.org/r/alpine.LRH.2.02.2006301414580.30526@file01.intranet.prod.int.rdu2.redhat.com). Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu

crypto: authenc - use crypto_grab_ahash() and simplify error paths

2020-01-09T03:30:55+00:00

Make the authenc template use the new function crypto_grab_ahash() to initialize its ahash spawn. This is needed to make all spawns be initialized in a consistent way. Also simplify the error handling by taking advantage of crypto_drop_*() now accepting (as a no-op) spawns that haven't been initialized yet, and by taking advantage of crypto_grab_*() now handling ERR_PTR() names. Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu

crypto: skcipher - pass instance to crypto_grab_skcipher()

2020-01-09T03:30:54+00:00

Initializing a crypto_skcipher_spawn currently requires: 1. Set spawn->base.inst to point to the instance. 2. Call crypto_grab_skcipher(). But there's no reason for these steps to be separate, and in fact this unneeded complication has caused at least one bug, the one fixed by commit 6db43410179b ("crypto: adiantum - initialize crypto_spawn::inst") So just make crypto_grab_skcipher() take the instance as an argument. To keep the function calls from getting too unwieldy due to this extra argument, also introduce a 'mask' variable into the affected places which weren't already using one. Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu

crypto: remove propagation of CRYPTO_TFM_RES_* flags

2020-01-09T03:30:53+00:00

The CRYPTO_TFM_RES_* flags were apparently meant as a way to make the ->setkey() functions provide more information about errors. But these flags weren't actually being used or tested, and in many cases they weren't being set correctly anyway. So they've now been removed. Also, if someone ever actually needs to start better distinguishing ->setkey() errors (which is somewhat unlikely, as this has been unneeded for a long time), we'd be much better off just defining different return values, like -EINVAL if the key is invalid for the algorithm vs. -EKEYREJECTED if the key was rejected by a policy like "no weak keys". That would be much simpler, less error-prone, and easier to test. So just remove CRYPTO_TFM_RES_MASK and all the unneeded logic that propagates these flags around. Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu

crypto: remove CRYPTO_TFM_RES_BAD_KEY_LEN

2020-01-09T03:30:53+00:00

The CRYPTO_TFM_RES_BAD_KEY_LEN flag was apparently meant as a way to make the ->setkey() functions provide more information about errors. However, no one actually checks for this flag, which makes it pointless. Also, many algorithms fail to set this flag when given a bad length key. Reviewing just the generic implementations, this is the case for aes-fixed-time, cbcmac, echainiv, nhpoly1305, pcrypt, rfc3686, rfc4309, rfc7539, rfc7539esp, salsa20, seqiv, and xcbc. But there are probably many more in arch/*/crypto/ and drivers/crypto/. Some algorithms can even set this flag when the key is the correct length. For example, authenc and authencesn set it when the key payload is malformed in any way (not just a bad length), the atmel-sha and ccree drivers can set it if a memory allocation fails, and the chelsio driver sets it for bad auth tag lengths, not just bad key lengths. So even if someone actually wanted to start checking this flag (which seems unlikely, since it's been unused for a long time), there would be a lot of work needed to get it working correctly. But it would probably be much better to go back to the drawing board and just define different return values, like -EINVAL if the key is invalid for the algorithm vs. -EKEYREJECTED if the key was rejected by a policy like "no weak keys". That would be much simpler, less error-prone, and easier to test. So just remove this flag. Signed-off-by: Eric Biggers Reviewed-by: Horia Geantă Signed-off-by: Herbert Xu

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

2019-05-30T18:26:32+00:00

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 Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman

crypto: run initcalls for generic implementations earlier

2019-04-18T14:15:03+00:00

Use subsys_initcall for registration of all templates and generic algorithm implementations, rather than module_init. Then change cryptomgr to use arch_initcall, to place it before the subsys_initcalls. This is needed so that when both a generic and optimized implementation of an algorithm are built into the kernel (not loadable modules), the generic implementation is registered before the optimized one. Otherwise, the self-tests for the optimized implementation are unable to allocate the generic implementation for the new comparison fuzz tests. Note that on arm, a side effect of this change is that self-tests for generic implementations may run before the unaligned access handler has been installed. So, unaligned accesses will crash the kernel. This is arguably a good thing as it makes it easier to detect that type of bug. Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu

crypto: authenc - fix parsing key with misaligned rta_len

2019-01-10T13:37:31+00:00

Keys for "authenc" AEADs are formatted as an rtattr containing a 4-byte 'enckeylen', followed by an authentication key and an encryption key. crypto_authenc_extractkeys() parses the key to find the inner keys. However, it fails to consider the case where the rtattr's payload is longer than 4 bytes but not 4-byte aligned, and where the key ends before the next 4-byte aligned boundary. In this case, 'keylen -= RTA_ALIGN(rta->rta_len);' underflows to a value near UINT_MAX. This causes a buffer overread and crash during crypto_ahash_setkey(). Fix it by restricting the rtattr payload to the expected size. Reproducer using AF_ALG: #include #include #include int main() { int fd; struct sockaddr_alg addr = { .salg_type = "aead", .salg_name = "authenc(hmac(sha256),cbc(aes))", }; struct { struct rtattr attr; __be32 enckeylen; char keys[1]; } __attribute__((packed)) key = { .attr.rta_len = sizeof(key), .attr.rta_type = 1 /* CRYPTO_AUTHENC_KEYA_PARAM */, }; fd = socket(AF_ALG, SOCK_SEQPACKET, 0); bind(fd, (void *)&addr, sizeof(addr)); setsockopt(fd, SOL_ALG, ALG_SET_KEY, &key, sizeof(key)); } It caused: BUG: unable to handle kernel paging request at ffff88007ffdc000 PGD 2e01067 P4D 2e01067 PUD 2e04067 PMD 2e05067 PTE 0 Oops: 0000 [#1] SMP CPU: 0 PID: 883 Comm: authenc Not tainted 4.20.0-rc1-00108-g00c9fe37a7f27 #13 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-20181126_142135-anatol 04/01/2014 RIP: 0010:sha256_ni_transform+0xb3/0x330 arch/x86/crypto/sha256_ni_asm.S:155 [...] Call Trace: sha256_ni_finup+0x10/0x20 arch/x86/crypto/sha256_ssse3_glue.c:321 crypto_shash_finup+0x1a/0x30 crypto/shash.c:178 shash_digest_unaligned+0x45/0x60 crypto/shash.c:186 crypto_shash_digest+0x24/0x40 crypto/shash.c:202 hmac_setkey+0x135/0x1e0 crypto/hmac.c:66 crypto_shash_setkey+0x2b/0xb0 crypto/shash.c:66 shash_async_setkey+0x10/0x20 crypto/shash.c:223 crypto_ahash_setkey+0x2d/0xa0 crypto/ahash.c:202 crypto_authenc_setkey+0x68/0x100 crypto/authenc.c:96 crypto_aead_setkey+0x2a/0xc0 crypto/aead.c:62 aead_setkey+0xc/0x10 crypto/algif_aead.c:526 alg_setkey crypto/af_alg.c:223 [inline] alg_setsockopt+0xfe/0x130 crypto/af_alg.c:256 __sys_setsockopt+0x6d/0xd0 net/socket.c:1902 __do_sys_setsockopt net/socket.c:1913 [inline] __se_sys_setsockopt net/socket.c:1910 [inline] __x64_sys_setsockopt+0x1f/0x30 net/socket.c:1910 do_syscall_64+0x4a/0x180 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Fixes: e236d4a89a2f ("[CRYPTO] authenc: Move enckeylen into key itself") Cc: # v2.6.25+ Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu

crypto: null - Remove VLA usage of skcipher

2018-09-28T04:46:08+00:00

In the quest to remove all stack VLA usage from the kernel[1], this replaces struct crypto_skcipher and SKCIPHER_REQUEST_ON_STACK() usage with struct crypto_sync_skcipher and SYNC_SKCIPHER_REQUEST_ON_STACK(), which uses a fixed stack size. [1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com Signed-off-by: Kees Cook Signed-off-by: Herbert Xu