On 5/10/23 23:33, Herbert Xu wrote:
Ross Philipson <ross.philipson@xxxxxxxxxx> wrote:+static void __sha_transform(u32 *digest, const char *data) +{ + u32 ws[SHA1_WORKSPACE_WORDS]; + + sha1_transform(digest, data, ws); + + memzero_explicit(ws, sizeof(ws)); +} + +void early_sha1_init(struct sha1_state *sctx) +{ + sha1_init(sctx->state); + sctx->count = 0; +} + +void early_sha1_update(struct sha1_state *sctx, + const u8 *data, + unsigned int len) +{ + unsigned int partial = sctx->count % SHA1_BLOCK_SIZE; + + sctx->count += len; + + if (likely((partial + len) >= SHA1_BLOCK_SIZE)) { + int blocks; + + if (partial) { + int p = SHA1_BLOCK_SIZE - partial; + + memcpy(sctx->buffer + partial, data, p); + data += p; + len -= p; + + __sha_transform(sctx->state, sctx->buffer); + } + + blocks = len / SHA1_BLOCK_SIZE; + len %= SHA1_BLOCK_SIZE; + + if (blocks) { + while (blocks--) { + __sha_transform(sctx->state, data); + data += SHA1_BLOCK_SIZE; + } + } + partial = 0; + } + + if (len) + memcpy(sctx->buffer + partial, data, len); +} + +void early_sha1_final(struct sha1_state *sctx, u8 *out) +{ + const int bit_offset = SHA1_BLOCK_SIZE - sizeof(__be64); + unsigned int partial = sctx->count % SHA1_BLOCK_SIZE; + __be64 *bits = (__be64 *)(sctx->buffer + bit_offset); + __be32 *digest = (__be32 *)out; + int i; + + sctx->buffer[partial++] = 0x80; + if (partial > bit_offset) { + memset(sctx->buffer + partial, 0x0, SHA1_BLOCK_SIZE - partial); + partial = 0; + + __sha_transform(sctx->state, sctx->buffer); + } + + memset(sctx->buffer + partial, 0x0, bit_offset - partial); + *bits = cpu_to_be64(sctx->count << 3); + __sha_transform(sctx->state, sctx->buffer); + + for (i = 0; i < SHA1_DIGEST_SIZE / sizeof(__be32); i++) + put_unaligned_be32(sctx->state[i], digest++); + + *sctx = (struct sha1_state){}; +}If we're going to add SHA1 then this should go into lib/crypto just like SHA2.
As mentioned before, this patch mimicked an early version for SHA2. We were remiss in not keeping it aligned with how the SHA2 evolved. I will take a closer look, but these wrappers may be able to go away and be reduced to just an include as SHA2 does these days.
v/r, dps
