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2025-07-14lib/crypto: sha2: Add hmac_sha*_init_usingrawkey()Eric Biggers
While the HMAC library functions support both incremental and one-shot computation and both prepared and raw keys, the combination of raw key + incremental was missing. It turns out that several potential users of the HMAC library functions (tpm2-sessions.c, smb2transport.c, trusted_tpm1.c) want exactly that. Therefore, add the missing functions hmac_sha*_init_usingrawkey(). Implement them in an optimized way that directly initializes the HMAC context without a separate key preparation step. Reimplement the one-shot raw key functions hmac_sha*_usingrawkey() on top of the new functions, which makes them a bit more efficient. Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20250711215844.41715-1-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@kernel.org>
2025-07-04lib/crypto: sha256: Sync sha256_update() with sha512_update()Eric Biggers
The BLOCK_HASH_UPDATE_BLOCKS macro is difficult to read. For now, let's just write the update explicitly in the straightforward way, mirroring sha512_update(). It's possible that we'll bring back a macro for this later, but it needs to be properly justified and hopefully a bit more readable. Acked-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20250630160645.3198-14-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@kernel.org>
2025-07-04lib/crypto: sha256: Consolidate into single moduleEric Biggers
Consolidate the CPU-based SHA-256 code into a single module, following what I did with SHA-512: - Each arch now provides a header file lib/crypto/$(SRCARCH)/sha256.h, replacing lib/crypto/$(SRCARCH)/sha256.c. The header defines sha256_blocks() and optionally sha256_mod_init_arch(). It is included by lib/crypto/sha256.c, and thus the code gets built into the single libsha256 module, with proper inlining and dead code elimination. - sha256_blocks_generic() is moved from lib/crypto/sha256-generic.c into lib/crypto/sha256.c. It's now a static function marked with __maybe_unused, so the compiler automatically eliminates it in any cases where it's not used. - Whether arch-optimized SHA-256 is buildable is now controlled centrally by lib/crypto/Kconfig instead of by lib/crypto/$(SRCARCH)/Kconfig. The conditions for enabling it remain the same as before, and it remains enabled by default. - Any additional arch-specific translation units for the optimized SHA-256 code (such as assembly files) are now compiled by lib/crypto/Makefile instead of lib/crypto/$(SRCARCH)/Makefile. Acked-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20250630160645.3198-13-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@kernel.org>
2025-07-04lib/crypto: sha256: Add HMAC-SHA224 and HMAC-SHA256 supportEric Biggers
Since HMAC support is commonly needed and is fairly simple, include it as a first-class citizen of the SHA-256 library. The API supports both incremental and one-shot computation, and either preparing the key ahead of time or just using a raw key. The implementation is much more streamlined than crypto/hmac.c. I've kept it consistent with the HMAC-SHA384 and HMAC-SHA512 code as much as possible. Testing of these functions will be via sha224_kunit and sha256_kunit, added by a later commit. Acked-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20250630160645.3198-9-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@kernel.org>
2025-07-04lib/crypto: sha256: Make library API use strongly-typed contextsEric Biggers
Currently the SHA-224 and SHA-256 library functions can be mixed arbitrarily, even in ways that are incorrect, for example using sha224_init() and sha256_final(). This is because they operate on the same structure, sha256_state. Introduce stronger typing, as I did for SHA-384 and SHA-512. Also as I did for SHA-384 and SHA-512, use the names *_ctx instead of *_state. The *_ctx names have the following small benefits: - They're shorter. - They avoid an ambiguity with the compression function state. - They're consistent with the well-known OpenSSL API. - Users usually name the variable 'sctx' anyway, which suggests that *_ctx would be the more natural name for the actual struct. Therefore: update the SHA-224 and SHA-256 APIs, implementation, and calling code accordingly. In the new structs, also strongly-type the compression function state. Acked-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20250630160645.3198-7-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@kernel.org>
2025-07-04lib/crypto: sha256: Add sha224() and sha224_update()Eric Biggers
Add a one-shot SHA-224 computation function sha224(), for consistency with sha256(), sha384(), and sha512() which all already exist. Similarly, add sha224_update(). While for now it's identical to sha256_update(), omitting it makes the API harder to use since users have to "know" which functions are the same between SHA-224 and SHA-256. Also, this is a prerequisite for using different context types for each. Acked-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20250630160645.3198-6-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@kernel.org>
2025-07-04lib/crypto: sha256: Reorder some codeEric Biggers
First, move the declarations of sha224_init/update/final to be just above the corresponding SHA-256 code, matching the order that I used for SHA-384 and SHA-512. In sha2.h, the end result is that SHA-224, SHA-256, SHA-384, and SHA-512 are all in the logical order. Second, move sha224_block_init() and sha256_block_init() to be just below crypto_sha256_state. In later changes, these functions as well as struct crypto_sha256_state will no longer be used by the library functions. They'll remain just for some legacy offload drivers. This gets them into a logical place in the file for that. No code changes other than reordering. Acked-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20250630160645.3198-4-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@kernel.org>
2025-06-30lib/crypto: Explicitly include <linux/export.h>Eric Biggers
Fix build warnings with W=1 that started appearing after commit a934a57a42f6 ("scripts/misc-check: check missing #include <linux/export.h> when W=1"). While at it, also sort the include lists alphabetically. (Keep asm/irqflags.h last, as otherwise it doesn't build on alpha.) This handles all of lib/crypto/, but not arch/*/lib/crypto/. The exports in arch/*/lib/crypto/ will go away when the code is properly integrated into lib/crypto/ as planned. Link: https://lore.kernel.org/r/20250613184814.50173-1-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@kernel.org>
2025-05-05crypto: lib/sha256 - Use generic block helperHerbert Xu
Use the BLOCK_HASH_UPDATE_BLOCKS helper instead of duplicating partial block handling. Also remove the unused lib/sha256 force-generic interface. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2025-05-05crypto: lib/sha256 - Add helpers for block-based shashHerbert Xu
Add an internal sha256_finup helper and move the finalisation code from __sha256_final into it. Also add sha256_choose_blocks and CRYPTO_ARCH_HAVE_LIB_SHA256_SIMD so that the Crypto API can use the SIMD block function unconditionally. The Crypto API must not be used in hard IRQs and there is no reason to have a fallback path for hardirqs. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2025-05-05crypto: lib/sha256 - improve function prototypesEric Biggers
Follow best practices by changing the length parameters to size_t and explicitly specifying the length of the output digest arrays. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2025-05-05crypto: sha256 - support arch-optimized lib and expose through shashEric Biggers
As has been done for various other algorithms, rework the design of the SHA-256 library to support arch-optimized implementations, and make crypto/sha256.c expose both generic and arch-optimized shash algorithms that wrap the library functions. This allows users of the SHA-256 library functions to take advantage of the arch-optimized code, and this makes it much simpler to integrate SHA-256 for each architecture. Note that sha256_base.h is not used in the new design. It will be removed once all the architecture-specific code has been updated. Move the generic block function into its own module to avoid a circular dependency from libsha256.ko => sha256-$ARCH.ko => libsha256.ko. Signed-off-by: Eric Biggers <ebiggers@google.com> Add export and import functions to maintain existing export format. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2025-04-23crypto: sha256_base - Remove partial block helpersHerbert Xu
Now that all sha256_base users have been converted to use the API partial block handling, remove the partial block helpers. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2025-04-23crypto: riscv/sha256 - Use API partial block handlingHerbert Xu
Use the Crypto API partial block handling. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2024-10-02move asm/unaligned.h to linux/unaligned.hAl Viro
asm/unaligned.h is always an include of asm-generic/unaligned.h; might as well move that thing to linux/unaligned.h and include that - there's nothing arch-specific in that header. auto-generated by the following: for i in `git grep -l -w asm/unaligned.h`; do sed -i -e "s/asm\/unaligned.h/linux\/unaligned.h/" $i done for i in `git grep -l -w asm-generic/unaligned.h`; do sed -i -e "s/asm-generic\/unaligned.h/linux\/unaligned.h/" $i done git mv include/asm-generic/unaligned.h include/linux/unaligned.h git mv tools/include/asm-generic/unaligned.h tools/include/linux/unaligned.h sed -i -e "/unaligned.h/d" include/asm-generic/Kbuild sed -i -e "s/__ASM_GENERIC/__LINUX/" include/linux/unaligned.h tools/include/linux/unaligned.h
2024-06-21crypto: lib - add missing MODULE_DESCRIPTION() macrosJeff Johnson
With ARCH=arm, make allmodconfig && make W=1 C=1 reports: WARNING: modpost: missing MODULE_DESCRIPTION() in lib/crypto/libsha256.o Add the missing invocation of the MODULE_DESCRIPTION() macro to all files which have a MODULE_LICENSE(). This includes sha1.c and utils.c which, although they did not produce a warning with the arm allmodconfig configuration, may cause this warning with other configurations. Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2023-05-19crypto: lib/sha256 - Use generic code from sha256_baseHerbert Xu
Instead of duplicating the sha256 block processing code, reuse the common code from crypto/sha256_base.h. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2023-05-19crypto: lib/sha256 - Remove redundant and unused sha224_updateHerbert Xu
The function sha224_update is exactly the same as sha256_update. Moreover it's not even used in the kernel so it can be removed. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-11-20crypto: sha - split sha.h into sha1.h and sha2.hEric Biggers
Currently <crypto/sha.h> contains declarations for both SHA-1 and SHA-2, and <crypto/sha3.h> contains declarations for SHA-3. This organization is inconsistent, but more importantly SHA-1 is no longer considered to be cryptographically secure. So to the extent possible, SHA-1 shouldn't be grouped together with any of the other SHA versions, and usage of it should be phased out. Therefore, split <crypto/sha.h> into two headers <crypto/sha1.h> and <crypto/sha2.h>, and make everyone explicitly specify whether they want the declarations for SHA-1, SHA-2, or both. This avoids making the SHA-1 declarations visible to files that don't want anything to do with SHA-1. It also prepares for potentially moving sha1.h into a new insecure/ or dangerous/ directory. Signed-off-by: Eric Biggers <ebiggers@google.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-10-30crypto: lib/sha256 - Unroll LOAD and BLEND loopsArvind Sankar
Unrolling the LOAD and BLEND loops improves performance by ~8% on x86_64 (tested on Broadwell Xeon) while not increasing code size too much. Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Reviewed-by: Eric Biggers <ebiggers@google.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-10-30crypto: lib/sha256 - Unroll SHA256 loop 8 times intead of 64Arvind Sankar
This reduces code size substantially (on x86_64 with gcc-10 the size of sha256_update() goes from 7593 bytes to 1952 bytes including the new SHA256_K array), and on x86 is slightly faster than the full unroll (tested on Broadwell Xeon). Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Reviewed-by: Eric Biggers <ebiggers@google.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-10-30crypto: lib/sha256 - Clear W[] in sha256_update() instead of sha256_transform()Arvind Sankar
The temporary W[] array is currently zeroed out once every call to sha256_transform(), i.e. once every 64 bytes of input data. Moving it to sha256_update() instead so that it is cleared only once per update can save about 2-3% of the total time taken to compute the digest, with a reasonable memset() implementation, and considerably more (~20%) with a bad one (eg the x86 purgatory currently uses a memset() coded in C). Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Reviewed-by: Eric Biggers <ebiggers@google.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-10-30crypto: lib/sha256 - Don't clear temporary variablesArvind Sankar
The assignments to clear a through h and t1/t2 are optimized out by the compiler because they are unused after the assignments. Clearing individual scalar variables is unlikely to be useful, as they may have been assigned to registers, and even if stack spilling was required, there may be compiler-generated temporaries that are impossible to clear in any case. So drop the clearing of a through h and t1/t2. Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Reviewed-by: Eric Biggers <ebiggers@google.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-10-30crypto: lib/sha256 - Use memzero_explicit() for clearing stateArvind Sankar
Without the barrier_data() inside memzero_explicit(), the compiler may optimize away the state-clearing if it can tell that the state is not used afterwards. At least in lib/crypto/sha256.c:__sha256_final(), the function can get inlined into sha256(), in which case the memset is optimized away. Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Reviewed-by: Eric Biggers <ebiggers@google.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-07-16crypto: lib/sha256 - add sha256() functionEric Biggers
Add a function sha256() which computes a SHA-256 digest in one step, combining sha256_init() + sha256_update() + sha256_final(). This is similar to how we also have blake2s(). Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Tested-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-05-08crypto: lib/sha256 - return voidEric Biggers
The SHA-256 / SHA-224 library functions can't fail, so remove the useless return value. Also long as the declarations are being changed anyway, also fix some parameter names in the declarations to match the definitions. Signed-off-by: Eric Biggers <ebiggers@google.com> Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-09-05crypto: sha256 - Remove sha256/224_init code duplicationHans de Goede
lib/crypto/sha256.c and include/crypto/sha256_base.h define 99% identical functions to init a sha256_state struct for sha224 or sha256 use. This commit moves the functions from lib/crypto/sha256.c to include/crypto/sha.h (making them static inline) and makes the sha224/256_base_init static inline functions from include/crypto/sha256_base.h wrappers around the now also static inline include/crypto/sha.h functions. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-09-05crypto: sha256 - Merge crypto/sha256.h into crypto/sha.hHans de Goede
The generic sha256 implementation from lib/crypto/sha256.c uses data structs defined in crypto/sha.h, so lets move the function prototypes there too. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-08-30crypto: sha256 - Add missing MODULE_LICENSE() to lib/crypto/sha256.cHans de Goede
lib/crypto/sha256.c / lib/crypto/libsha256.o may end up being a module, so it needs a MODULE_LICENSE() line, add this. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-08-22crypto: sha256 - Add sha224 support to sha256 library codeHans de Goede
Add sha224 support to the lib/crypto/sha256 library code. This will allow us to replace both the sha256 and sha224 parts of crypto/sha256_generic.c when we remove the code duplication in further patches in this series. Suggested-by: Eric Biggers <ebiggers@kernel.org> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-08-22crypto: sha256 - Make lib/crypto/sha256.c suitable for generic useHans de Goede
Before this commit lib/crypto/sha256.c has only been used in the s390 and x86 purgatory code, make it suitable for generic use: * Export interesting symbols * Add -D__DISABLE_EXPORTS to CFLAGS_sha256.o for purgatory builds to avoid the exports for the purgatory builds * Add to lib/crypto/Makefile and crypto/Kconfig Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-08-22crypto: sha256 - Use get/put_unaligned_be32 to get input, memzero_explicitHans de Goede
Use get/put_unaligned_be32 in lib/crypto/sha256.c to load / store data so that it can be used with unaligned buffers too, making it more generic. And use memzero_explicit for better clearing of sensitive data. Note unlike other patches in this series this commit actually makes functional changes to the sha256 code as used by the purgatory code. This fully aligns the lib/crypto/sha256.c sha256 implementation with the one from crypto/sha256_generic.c allowing us to remove the latter in further patches in this series. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-08-22crypto: sha256 - Move lib/sha256.c to lib/cryptoHans de Goede
Generic crypto implementations belong under lib/crypto not directly in lib, likewise the header should be in include/crypto, not include/linux. Note that the code in lib/crypto/sha256.c is not yet available for generic use after this commit, it is still only used by the s390 and x86 purgatory code. Making it suitable for generic use is done in further patches in this series. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>