kernel/linux.git/crypto/xts.c, branch v6.12.80

crypto: xts - Only add ecb if it is not already there

2025-06-19T13:31:30+00:00

[ Upstream commit 270b6f13454cb7f2f7058c50df64df409c5dcf55 ] Only add ecb to the cipher name if it isn't already ecb. Also use memcmp instead of strncmp since these strings are all stored in an array of length CRYPTO_MAX_ALG_NAME. Fixes: f1c131b45410 ("crypto: xts - Convert to skcipher") Signed-off-by: Herbert Xu Signed-off-by: Sasha Levin

crypto: xts - use 'spawn' for underlying single-block cipher

2023-10-20T05:39:25+00:00

Since commit adad556efcdd ("crypto: api - Fix built-in testing dependency failures"), the following warning appears when booting an x86_64 kernel that is configured with CONFIG_CRYPTO_MANAGER_EXTRA_TESTS=y and CONFIG_CRYPTO_AES_NI_INTEL=y, even when CONFIG_CRYPTO_XTS=y and CONFIG_CRYPTO_AES=y: alg: skcipher: skipping comparison tests for xts-aes-aesni because xts(ecb(aes-generic)) is unavailable This is caused by an issue in the xts template where it allocates an "aes" single-block cipher without declaring a dependency on it via the crypto_spawn mechanism. This issue was exposed by the above commit because it reversed the order that the algorithms are tested in. Specifically, when "xts(ecb(aes-generic))" is instantiated and tested during the comparison tests for "xts-aes-aesni", the "xts" template allocates an "aes" crypto_cipher for encrypting tweaks. This resolves to "aes-aesni". (Getting "aes-aesni" instead of "aes-generic" here is a bit weird, but it's apparently intended.) Due to the above-mentioned commit, the testing of "aes-aesni", and the finalization of its registration, now happens at this point instead of before. At the end of that, crypto_remove_spawns() unregisters all algorithm instances that depend on a lower-priority "aes" implementation such as "aes-generic" but that do not depend on "aes-aesni". However, because "xts" does not use the crypto_spawn mechanism for its "aes", its dependency on "aes-aesni" is not recognized by crypto_remove_spawns(). Thus, crypto_remove_spawns() unexpectedly unregisters "xts(ecb(aes-generic))". Fix this issue by making the "xts" template use the crypto_spawn mechanism for its "aes" dependency, like what other templates do. Note, this fix could be applied as far back as commit f1c131b45410 ("crypto: xts - Convert to skcipher"). However, the issue only got exposed by the much more recent changes to how the crypto API runs the self-tests, so there should be no need to backport this to very old kernels. Also, an alternative fix would be to flip the list iteration order in crypto_start_tests() to restore the original testing order. I'm thinking we should do that too, since the original order seems more natural, but it shouldn't be relied on for correctness. Fixes: adad556efcdd ("crypto: api - Fix built-in testing dependency failures") Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu

crypto: xts - Only access common skcipher fields on spawn

2023-10-13T10:27:27+00:00

As skcipher spawns may be of the type lskcipher, only the common fields may be accessed. This was already the case but use the correct helpers to make this more obvious. Signed-off-by: Herbert Xu

crypto: lrw,xts - Replace strlcpy with strscpy

2023-07-14T08:23:14+00:00

strlcpy() reads the entire source buffer first. This read may exceed the destination size limit. This is both inefficient and can lead to linear read overflows if a source string is not NUL-terminated [1]. In an effort to remove strlcpy() completely [2], replace strlcpy() here with strscpy(). Direct replacement is safe here since return value of -errno is used to check for truncation instead of sizeof(dest). [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy [2] https://github.com/KSPP/linux/issues/89 Signed-off-by: Azeem Shaikh Reviewed-by: Kees Cook Signed-off-by: Herbert Xu

crypto: api - Use data directly in completion function

2023-02-13T10:35:14+00:00

This patch does the final flag day conversion of all completion functions which are now all contained in the Crypto API. Signed-off-by: Herbert Xu

crypto: xts - Handle EBUSY correctly

2023-01-27T10:58:09+00:00

As it is xts only handles the special return value of EINPROGRESS, which means that in all other cases it will free data related to the request. However, as the caller of xts may specify MAY_BACKLOG, we also need to expect EBUSY and treat it in the same way. Otherwise backlogged requests will trigger a use-after-free. Fixes: 8083b1bf8163 ("crypto: xts - add support for ciphertext stealing") Signed-off-by: Herbert Xu Acked-by: Ard Biesheuvel Signed-off-by: Herbert Xu

crypto: xts - Add softdep on ecb

2022-02-18T05:21:08+00:00

The xts module needs ecb to be present as it's meant to work on top of ecb. This patch adds a softdep so ecb can be included automatically into the initramfs. Reported-by: rftc Signed-off-by: Herbert Xu

crypto: remove cipher routines from public crypto API

2021-01-02T21:41:35+00:00

The cipher routines in the crypto API are mostly intended for templates implementing skcipher modes generically in software, and shouldn't be used outside of the crypto subsystem. So move the prototypes and all related definitions to a new header file under include/crypto/internal. Also, let's use the new module namespace feature to move the symbol exports into a new namespace CRYPTO_INTERNAL. Signed-off-by: Ard Biesheuvel Acked-by: Eric Biggers Signed-off-by: Herbert Xu

crypto: xts - Replace memcpy() invocation with simple assignment

2020-07-31T08:09:00+00:00

Colin reports that the memcpy() call in xts_cts_final() trigggers a "Overlapping buffer in memory copy" warning in Coverity, which is a false postive, given that tail is guaranteed to be smaller than or equal to the distance between source and destination. However, given that any additional bytes that we copy will be ignored anyway, we can simply copy XTS_BLOCK_SIZE unconditionally, which means we can use struct assignment of the array members instead, which is likely to be more efficient as well. Addresses-Coverity: ("Overlapping buffer in memory copy") Fixes: 8083b1bf8163 ("crypto: xts - add support for ciphertext stealing") Reported-by: Colin Ian King Signed-off-by: Ard Biesheuvel Signed-off-by: Herbert Xu

crypto: xts - prefix function and struct names with "xts"

2020-07-16T11:49:13+00:00

Overly-generic names can cause problems like naming collisions, confusing crash reports, and reduced grep-ability. E.g. see commit d099ea6e6fde ("crypto - Avoid free() namespace collision"). Clean this up for the xts template by prefixing the names with "xts_". (I didn't use "crypto_xts_" instead because that seems overkill.) Also constify the tfm context in a couple places, and make xts_free_instance() use the instance context structure so that it doesn't just assume the crypto_skcipher_spawn is at the beginning. Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu