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author | Eric Biggers <ebiggers@google.com> | 2018-11-16 17:26:21 -0800 |
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committer | Herbert Xu <herbert@gondor.apana.org.au> | 2018-11-20 14:26:55 +0800 |
commit | 1ca1b917940c24ca3d1f490118c5474168622953 (patch) | |
tree | 26cde5a85d0792a8dd709a6f5316f76af8801a35 /crypto/chacha20poly1305.c | |
parent | de61d7ae5d3789dcba3749a418f76613fbee8414 (diff) | |
download | lwn-1ca1b917940c24ca3d1f490118c5474168622953.tar.gz lwn-1ca1b917940c24ca3d1f490118c5474168622953.zip |
crypto: chacha20-generic - refactor to allow varying number of rounds
In preparation for adding XChaCha12 support, rename/refactor
chacha20-generic to support different numbers of rounds. The
justification for needing XChaCha12 support is explained in more detail
in the patch "crypto: chacha - add XChaCha12 support".
The only difference between ChaCha{8,12,20} are the number of rounds
itself; all other parts of the algorithm are the same. Therefore,
remove the "20" from all definitions, structures, functions, files, etc.
that will be shared by all ChaCha versions.
Also make ->setkey() store the round count in the chacha_ctx (previously
chacha20_ctx). The generic code then passes the round count through to
chacha_block(). There will be a ->setkey() function for each explicitly
allowed round count; the encrypt/decrypt functions will be the same. I
decided not to do it the opposite way (same ->setkey() function for all
round counts, with different encrypt/decrypt functions) because that
would have required more boilerplate code in architecture-specific
implementations of ChaCha and XChaCha.
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Martin Willi <martin@strongswan.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'crypto/chacha20poly1305.c')
-rw-r--r-- | crypto/chacha20poly1305.c | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/crypto/chacha20poly1305.c b/crypto/chacha20poly1305.c index f9dd5453046a..fef11446ab1b 100644 --- a/crypto/chacha20poly1305.c +++ b/crypto/chacha20poly1305.c @@ -13,7 +13,7 @@ #include <crypto/internal/hash.h> #include <crypto/internal/skcipher.h> #include <crypto/scatterwalk.h> -#include <crypto/chacha20.h> +#include <crypto/chacha.h> #include <crypto/poly1305.h> #include <linux/err.h> #include <linux/init.h> @@ -49,7 +49,7 @@ struct poly_req { }; struct chacha_req { - u8 iv[CHACHA20_IV_SIZE]; + u8 iv[CHACHA_IV_SIZE]; struct scatterlist src[1]; struct skcipher_request req; /* must be last member */ }; @@ -89,7 +89,7 @@ static void chacha_iv(u8 *iv, struct aead_request *req, u32 icb) memcpy(iv, &leicb, sizeof(leicb)); memcpy(iv + sizeof(leicb), ctx->salt, ctx->saltlen); memcpy(iv + sizeof(leicb) + ctx->saltlen, req->iv, - CHACHA20_IV_SIZE - sizeof(leicb) - ctx->saltlen); + CHACHA_IV_SIZE - sizeof(leicb) - ctx->saltlen); } static int poly_verify_tag(struct aead_request *req) @@ -492,7 +492,7 @@ static int chachapoly_setkey(struct crypto_aead *aead, const u8 *key, struct chachapoly_ctx *ctx = crypto_aead_ctx(aead); int err; - if (keylen != ctx->saltlen + CHACHA20_KEY_SIZE) + if (keylen != ctx->saltlen + CHACHA_KEY_SIZE) return -EINVAL; keylen -= ctx->saltlen; @@ -637,7 +637,7 @@ static int chachapoly_create(struct crypto_template *tmpl, struct rtattr **tb, err = -EINVAL; /* Need 16-byte IV size, including Initial Block Counter value */ - if (crypto_skcipher_alg_ivsize(chacha) != CHACHA20_IV_SIZE) + if (crypto_skcipher_alg_ivsize(chacha) != CHACHA_IV_SIZE) goto out_drop_chacha; /* Not a stream cipher? */ if (chacha->base.cra_blocksize != 1) |