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2020-07-16crypto: algapi - use common mechanism for inheriting flagsEric Biggers1-2/+3
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 <mpatocka@redhat.com> (https://lore.kernel.org/r/alpine.LRH.2.02.2006301414580.30526@file01.intranet.prod.int.rdu2.redhat.com). Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-01-09crypto: shash - convert shash_free_instance() to new styleEric Biggers1-2/+3
Convert shash_free_instance() and its users to the new way of freeing instances, where a ->free() method is installed to the instance struct itself. This replaces the weakly-typed method crypto_template::free(). This will allow removing support for the old way of freeing instances. Also give shash_free_instance() a more descriptive name to reflect that it's only for instances with a single spawn, not for any instance. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-01-09crypto: cipher - make crypto_spawn_cipher() take a crypto_cipher_spawnEric Biggers1-1/+1
Now that all users of single-block cipher spawns have been converted to use 'struct crypto_cipher_spawn' rather than the less specifically typed 'struct crypto_spawn', make crypto_spawn_cipher() take a pointer to a 'struct crypto_cipher_spawn' rather than a 'struct crypto_spawn'. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-01-09crypto: vmac - use crypto_grab_cipher() and simplify error pathsEric Biggers1-18/+15
Make the vmac64 template use the new function crypto_grab_cipher() to initialize its cipher spawn. This is needed to make all spawns be initialized in a consistent way. This required making vmac_create() allocate the instance directly rather than use shash_alloc_instance(). 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 <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-01-09crypto: remove CRYPTO_TFM_RES_BAD_KEY_LENEric Biggers1-3/+1
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 <ebiggers@google.com> Reviewed-by: Horia Geantă <horia.geanta@nxp.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-04-18crypto: run initcalls for generic implementations earlierEric Biggers1-1/+1
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 <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-07-01crypto: vmac - remove insecure version with hardcoded nonceEric Biggers1-77/+7
Remove the original version of the VMAC template that had the nonce hardcoded to 0 and produced a digest with the wrong endianness. I'm unsure whether this had users or not (there are no explicit in-kernel references to it), but given that the hardcoded nonce made it wildly insecure unless a unique key was used for each message, let's try removing it and see if anyone complains. Leave the new "vmac64" template that requires the nonce to be explicitly specified as the first 16 bytes of data and uses the correct endianness for the digest. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-07-01crypto: vmac - add nonced version with big endian digestEric Biggers1-18/+112
Currently the VMAC template uses a "nonce" hardcoded to 0, which makes it insecure unless a unique key is set for every message. Also, the endianness of the final digest is wrong: the implementation uses little endian, but the VMAC specification has it as big endian, as do other VMAC implementations such as the one in Crypto++. Add a new VMAC template where the nonce is passed as the first 16 bytes of data (similar to what is done for Poly1305's nonce), and the digest is big endian. Call it "vmac64", since the old name of simply "vmac" didn't clarify whether the implementation is of VMAC-64 or of VMAC-128 (which produce 64-bit and 128-bit digests respectively); so we fix the naming ambiguity too. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-07-01crypto: vmac - separate tfm and request contextEric Biggers1-227/+181
syzbot reported a crash in vmac_final() when multiple threads concurrently use the same "vmac(aes)" transform through AF_ALG. The bug is pretty fundamental: the VMAC template doesn't separate per-request state from per-tfm (per-key) state like the other hash algorithms do, but rather stores it all in the tfm context. That's wrong. Also, vmac_final() incorrectly zeroes most of the state including the derived keys and cached pseudorandom pad. Therefore, only the first VMAC invocation with a given key calculates the correct digest. Fix these bugs by splitting the per-tfm state from the per-request state and using the proper init/update/final sequencing for requests. Reproducer for the crash: #include <linux/if_alg.h> #include <sys/socket.h> #include <unistd.h> int main() { int fd; struct sockaddr_alg addr = { .salg_type = "hash", .salg_name = "vmac(aes)", }; char buf[256] = { 0 }; fd = socket(AF_ALG, SOCK_SEQPACKET, 0); bind(fd, (void *)&addr, sizeof(addr)); setsockopt(fd, SOL_ALG, ALG_SET_KEY, buf, 16); fork(); fd = accept(fd, NULL, NULL); for (;;) write(fd, buf, 256); } The immediate cause of the crash is that vmac_ctx_t.partial_size exceeds VMAC_NHBYTES, causing vmac_final() to memset() a negative length. Reported-by: syzbot+264bca3a6e8d645550d3@syzkaller.appspotmail.com Fixes: f1939f7c5645 ("crypto: vmac - New hash algorithm for intel_txt support") Cc: <stable@vger.kernel.org> # v2.6.32+ Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-07-01crypto: vmac - require a block cipher with 128-bit block sizeEric Biggers1-0/+4
The VMAC template assumes the block cipher has a 128-bit block size, but it failed to check for that. Thus it was possible to instantiate it using a 64-bit block size cipher, e.g. "vmac(cast5)", causing uninitialized memory to be used. Add the needed check when instantiating the template. Fixes: f1939f7c5645 ("crypto: vmac - New hash algorithm for intel_txt support") Cc: <stable@vger.kernel.org> # v2.6.32+ Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-11-26crypto: include crypto- module prefix in templateKees Cook1-0/+1
This adds the module loading prefix "crypto-" to the template lookup as well. For example, attempting to load 'vfat(blowfish)' via AF_ALG now correctly includes the "crypto-" prefix at every level, correctly rejecting "vfat": net-pf-38 algif-hash crypto-vfat(blowfish) crypto-vfat(blowfish)-all crypto-vfat Reported-by: Mathias Krause <minipli@googlemail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Mathias Krause <minipli@googlemail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-10-17crypto: memzero_explicit - make sure to clear out sensitive dataDaniel Borkmann1-1/+1
Recently, in commit 13aa93c70e71 ("random: add and use memzero_explicit() for clearing data"), we have found that GCC may optimize some memset() cases away when it detects a stack variable is not being used anymore and going out of scope. This can happen, for example, in cases when we are clearing out sensitive information such as keying material or any e.g. intermediate results from crypto computations, etc. With the help of Coccinelle, we can figure out and fix such occurences in the crypto subsytem as well. Julia Lawall provided the following Coccinelle program: @@ type T; identifier x; @@ T x; ... when exists when any -memset +memzero_explicit (&x, -0, ...) ... when != x when strict @@ type T; identifier x; @@ T x[...]; ... when exists when any -memset +memzero_explicit (x, -0, ...) ... when != x when strict Therefore, make use of the drop-in replacement memzero_explicit() for exactly such cases instead of using memset(). Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Cc: Julia Lawall <julia.lawall@lip6.fr> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Theodore Ts'o <tytso@mit.edu> Cc: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2012-10-15crypto: vmac - Make VMAC work when blocks aren't alignedSalman Qazi1-4/+43
VMAC implementation, as it is, does not work with blocks that are not multiples of 128-bytes. Furthermore, this is a problem when using the implementation on scatterlists, even when the complete plain text is 128-byte multiple, as the pieces that get passed to vmac_update can be pretty much any size. I also added test cases for unaligned blocks. Signed-off-by: Salman Qazi <sqazi@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2012-09-07crypto: crypto_user - fix sparse warnings (symbol was not declared, should ↵Jussi Kivilinna1-5/+5
be static?) Fix "symbol 'x' was not declared. Should it be static?" sparse warnings. Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2011-10-31crypto: add module.h to those files that are explicitly using itPaul Gortmaker1-0/+1
Part of the include cleanups means that the implicit inclusion of module.h via device.h is going away. So fix things up in advance. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-03-31Fix common misspellingsLucas De Marchi1-1/+1
Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2010-03-18crypto: vmac - Fix big-endian supportShane Wang1-39/+36
This patch is to fix the vmac algorithm, add more test cases for vmac, and fix the test failure on some big endian system like s390. Signed-off-by: Shane Wang <shane.wang@intel.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2009-09-02crypto: vmac - New hash algorithm for intel_txt supportShane Wang1-0/+678
This patch adds VMAC (a fast MAC) support into crypto framework. Signed-off-by: Shane Wang <shane.wang@intel.com> Signed-off-by: Joseph Cihula <joseph.cihula@intel.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>