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| author |  brian m. carlson <sandals@crustytoothpaste.net> | 2018-11-14 04:09:36 +0000 |
|---|---|---|
| committer |  Junio C Hamano <gitster@pobox.com> | 2018-11-14 16:54:53 +0900 |
| commit | 13eeedb5d17ca3539600b6618d103b652ecc8ab0 (patch) | |
| tree | 4b4dd03dafa7c67d234c8f6da3e49c4a80234f76 /sha256/block/sha256.h | |
| parent | commit-graph: convert to using the_hash_algo (diff) | |
| download | tgif-13eeedb5d17ca3539600b6618d103b652ecc8ab0.tar.xz | |
Add a base implementation of SHA-256 support
SHA-1 is weak and we need to transition to a new hash function. For
some time, we have referred to this new function as NewHash. Recently,
we decided to pick SHA-256 as NewHash. The reasons behind the choice of
SHA-256 are outlined in the thread starting at [1] and in the commit
history for the hash function transition document.
Add a basic implementation of SHA-256 based off libtomcrypt, which is in
the public domain. Optimize it and restructure it to meet our coding
standards. Pull in the update and final functions from the SHA-1 block
implementation, as we know these function correctly with all compilers.
This implementation is slower than SHA-1, but more performant
implementations will be introduced in future commits.
Wire up SHA-256 in the list of hash algorithms, and add a test that the
algorithm works correctly.
Note that with this patch, it is still not possible to switch to using
SHA-256 in Git. Additional patches are needed to prepare the code to
handle a larger hash algorithm and further test fixes are needed.
[1] https://public-inbox.org/git/20180609224913.GC38834@genre.crustytoothpaste.net/
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Diffstat (limited to 'sha256/block/sha256.h')
| -rw-r--r-- | sha256/block/sha256.h | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/sha256/block/sha256.h b/sha256/block/sha256.h new file mode 100644 index 0000000000..5099d6421d --- /dev/null +++ b/sha256/block/sha256.h @@ -0,0 +1,24 @@ +#ifndef SHA256_BLOCK_SHA256_H +#define SHA256_BLOCK_SHA256_H + +#define blk_SHA256_BLKSIZE 64 + +struct blk_SHA256_CTX { + uint32_t state[8]; + uint64_t size; + uint32_t offset; + uint8_t buf[blk_SHA256_BLKSIZE]; +}; + +typedef struct blk_SHA256_CTX blk_SHA256_CTX; + +void blk_SHA256_Init(blk_SHA256_CTX *ctx); +void blk_SHA256_Update(blk_SHA256_CTX *ctx, const void *data, size_t len); +void blk_SHA256_Final(unsigned char *digest, blk_SHA256_CTX *ctx); + +#define platform_SHA256_CTX blk_SHA256_CTX +#define platform_SHA256_Init blk_SHA256_Init +#define platform_SHA256_Update blk_SHA256_Update +#define platform_SHA256_Final blk_SHA256_Final + +#endif |