09 Jan, 2020
1 commit
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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
18 Apr, 2019
1 commit
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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
27 May, 2018
2 commits
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The __crc32_le() wrapper function is pointless. Just call crc32_le()
directly instead.Signed-off-by: Eric Biggers
Signed-off-by: Herbert Xu -
crc32-generic doesn't have a cra_alignmask set, which is desired as its
->update() works with any alignment. However, it incorrectly assumes
4-byte alignment in ->setkey() and when outputting the final digest.Fix this by using the unaligned access macros in those cases.
Signed-off-by: Eric Biggers
Signed-off-by: Herbert Xu
12 Jan, 2018
1 commit
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We need to consistently enforce that keyed hashes cannot be used without
setting the key. To do this we need a reliable way to determine whether
a given hash algorithm is keyed or not. AF_ALG currently does this by
checking for the presence of a ->setkey() method. However, this is
actually slightly broken because the CRC-32 algorithms implement
->setkey() but can also be used without a key. (The CRC-32 "key" is not
actually a cryptographic key but rather represents the initial state.
If not overridden, then a default initial state is used.)Prepare to fix this by introducing a flag CRYPTO_ALG_OPTIONAL_KEY which
indicates that the algorithm has a ->setkey() method, but it is not
required to be called. Then set it on all the CRC-32 algorithms.The same also applies to the Adler-32 implementation in Lustre.
Also, the cryptd and mcryptd templates have to pass through the flag
from their underlying algorithm.Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers
Signed-off-by: Herbert Xu
30 Jan, 2016
1 commit
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The generic crc32 implementation is currently called crc32. This
is a problem because it clashes with the lib implementation of crc32.This patch renames the crypto crc32 to crc32_generic so that it is
consistent with crc32c. An alias for the driver is also added.Signed-off-by: Herbert Xu
