Commit f03f8096 authored Nov 12, 2019 by David Sterba Committed by Alistair Delva Oct 23, 2021

UPSTREAM: crypto: blake2b - simplify key init



The keyed init writes the key bytes to the input buffer and does an
update. We can do that in two ways: fill the buffer and update
immediatelly. This is what current blake2b_init_key does. Any other
following _update or _final will continue from the updated state.

The other way is to write the key and set the number of bytes to process
at the next _update or _final, lazy evaluation. Which leads to the the
simplified code in this patch.

Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

(cherry picked from commit e87e484d60b0da8302b45f27fe32af1cea02c8d2)
Bug: 178411248
Change-Id: I90652bb41d252af9503d5976ce32b93e2610debf
Signed-off-by: Eric Biggers <ebiggers@google.com>

parent fdb0b246

crypto/blake2b_generic.c

+6 −8

Original line number	Diff line number	Diff line
		@@ -85,8 +85,6 @@ static const u8 blake2b_sigma[12][16] = {
		{ 14, 10, 4, 8, 9, 15, 13, 6, 1, 12, 0, 2, 11, 7, 5, 3 }
		};

		static void blake2b_update(struct blake2b_state S, const void pin, size_t inlen);

		static void blake2b_set_lastnode(struct blake2b_state *S)
		{
		S->f[1] = (u64)-1;
		@@ -235,12 +233,12 @@ static int blake2b_init(struct shash_desc *desc)
		state->h[0] ^= 0x01010000 \| mctx->keylen << 8 \| digestsize;

		if (mctx->keylen) {
		u8 block[BLAKE2B_BLOCKBYTES];

		memset(block, 0, BLAKE2B_BLOCKBYTES);
		memcpy(block, mctx->key, mctx->keylen);
		blake2b_update(state, block, BLAKE2B_BLOCKBYTES);
		memzero_explicit(block, BLAKE2B_BLOCKBYTES);
		/*
		* Prefill the buffer with the key, next call to _update or
		* _final will process it
		*/
		memcpy(state->buf, mctx->key, mctx->keylen);
		state->buflen = BLAKE2B_BLOCKBYTES;
		}
		return 0;
		}