Commit 773d2b99 authored by Eric Biggers's avatar Eric Biggers
Browse files

lib/crypto: sha256: Sync sha256_update() with sha512_update() 



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: default avatarArd Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20250630160645.3198-14-ebiggers@kernel.org


Signed-off-by: default avatarEric Biggers <ebiggers@kernel.org>
parent e96cb950

lib/crypto/sha256.c

+25 −3
Original line number Diff line number Diff line
@@ -10,7 +10,6 @@ 
 */



#include <crypto/hmac.h>

#include <crypto/internal/blockhash.h>

#include <crypto/sha2.h>

#include <linux/export.h>

#include <linux/kernel.h>
@@ -180,8 +179,31 @@ void __sha256_update(struct __sha256_ctx *ctx, const u8 *data, size_t len) 
	size_t partial = ctx->bytecount % SHA256_BLOCK_SIZE;



	ctx->bytecount += len;

	BLOCK_HASH_UPDATE_BLOCKS(sha256_blocks, &ctx->state, data, len,

				 SHA256_BLOCK_SIZE, ctx->buf, partial);



	if (partial + len >= SHA256_BLOCK_SIZE) {

		size_t nblocks;



		if (partial) {

			size_t l = SHA256_BLOCK_SIZE - partial;



			memcpy(&ctx->buf[partial], data, l);

			data += l;

			len -= l;



			sha256_blocks(&ctx->state, ctx->buf, 1);

		}



		nblocks = len / SHA256_BLOCK_SIZE;

		len %= SHA256_BLOCK_SIZE;



		if (nblocks) {

			sha256_blocks(&ctx->state, data, nblocks);

			data += nblocks * SHA256_BLOCK_SIZE;

		}

		partial = 0;

	}

	if (len)

		memcpy(&ctx->buf[partial], data, len);

}

EXPORT_SYMBOL(__sha256_update);