crypto: shash - Require all algorithms to support export/import

This patch provides a default export/import function for all
shash algorithms.  It simply copies the descriptor context as
is done by sha1_generic.

This in essence means that all existing shash algorithms now
support export/import.  This is something that will be depended
upon in implementations such as hmac.  Therefore all new shash
and ahash implementations must support export/import.

For those that cannot obtain a partial result, padlock-sha's
fallback model should be used so that a partial result is always
available.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Herbert Xu 2009-07-22 12:37:06 +08:00
parent 9fadfd1adf
commit f592682f9f

View File

@ -183,14 +183,16 @@ int crypto_shash_digest(struct shash_desc *desc, const u8 *data,
}
EXPORT_SYMBOL_GPL(crypto_shash_digest);
static int shash_no_export(struct shash_desc *desc, void *out)
static int shash_default_export(struct shash_desc *desc, void *out)
{
return -ENOSYS;
memcpy(out, shash_desc_ctx(desc), crypto_shash_descsize(desc->tfm));
return 0;
}
static int shash_no_import(struct shash_desc *desc, const void *in)
static int shash_default_import(struct shash_desc *desc, const void *in)
{
return -ENOSYS;
memcpy(shash_desc_ctx(desc), in, crypto_shash_descsize(desc->tfm));
return 0;
}
static int shash_async_setkey(struct crypto_ahash *tfm, const u8 *key,
@ -563,10 +565,11 @@ static int shash_prepare_alg(struct shash_alg *alg)
alg->finup = shash_finup_unaligned;
if (!alg->digest)
alg->digest = shash_digest_unaligned;
if (!alg->import)
alg->import = shash_no_import;
if (!alg->export)
alg->export = shash_no_export;
if (!alg->export) {
alg->export = shash_default_export;
alg->import = shash_default_import;
alg->statesize = alg->descsize;
}
if (!alg->setkey)
alg->setkey = shash_no_setkey;