crypto: arm64/gcm - disentangle ghash and gcm setkey() routines

The remaining ghash implementation does not support aggregation, and so
there is no point in including the precomputed powers of H in the key
struct. So move that into the GCM setkey routine, and get rid of the
shared sub-routine entirely.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Ard Biesheuvel 2020-06-29 09:39:22 +02:00 committed by Herbert Xu
parent 37b6aab68f
commit 94fe4501cd

View File

@ -184,29 +184,6 @@ static void ghash_reflect(u64 h[], const be128 *k)
h[1] ^= 0xc200000000000000UL;
}
static int __ghash_setkey(struct ghash_key *key,
const u8 *inkey, unsigned int keylen)
{
be128 h;
/* needed for the fallback */
memcpy(&key->k, inkey, GHASH_BLOCK_SIZE);
ghash_reflect(key->h, &key->k);
h = key->k;
gf128mul_lle(&h, &key->k);
ghash_reflect(key->h2, &h);
gf128mul_lle(&h, &key->k);
ghash_reflect(key->h3, &h);
gf128mul_lle(&h, &key->k);
ghash_reflect(key->h4, &h);
return 0;
}
static int ghash_setkey(struct crypto_shash *tfm,
const u8 *inkey, unsigned int keylen)
{
@ -215,7 +192,11 @@ static int ghash_setkey(struct crypto_shash *tfm,
if (keylen != GHASH_BLOCK_SIZE)
return -EINVAL;
return __ghash_setkey(key, inkey, keylen);
/* needed for the fallback */
memcpy(&key->k, inkey, GHASH_BLOCK_SIZE);
ghash_reflect(key->h, &key->k);
return 0;
}
static struct shash_alg ghash_alg = {
@ -251,6 +232,7 @@ static int gcm_setkey(struct crypto_aead *tfm, const u8 *inkey,
{
struct gcm_aes_ctx *ctx = crypto_aead_ctx(tfm);
u8 key[GHASH_BLOCK_SIZE];
be128 h;
int ret;
ret = aes_expandkey(&ctx->aes_key, inkey, keylen);
@ -259,7 +241,22 @@ static int gcm_setkey(struct crypto_aead *tfm, const u8 *inkey,
aes_encrypt(&ctx->aes_key, key, (u8[AES_BLOCK_SIZE]){});
return __ghash_setkey(&ctx->ghash_key, key, sizeof(be128));
/* needed for the fallback */
memcpy(&ctx->ghash_key.k, key, GHASH_BLOCK_SIZE);
ghash_reflect(ctx->ghash_key.h, &ctx->ghash_key.k);
h = ctx->ghash_key.k;
gf128mul_lle(&h, &ctx->ghash_key.k);
ghash_reflect(ctx->ghash_key.h2, &h);
gf128mul_lle(&h, &ctx->ghash_key.k);
ghash_reflect(ctx->ghash_key.h3, &h);
gf128mul_lle(&h, &ctx->ghash_key.k);
ghash_reflect(ctx->ghash_key.h4, &h);
return 0;
}
static int gcm_setauthsize(struct crypto_aead *tfm, unsigned int authsize)