From: Eric Biggers <ebiggers@xxxxxxxxxx>
For an shash algorithm that doesn't implement ->digest, currently
crypto_shash_digest() with aligned input makes 5 indirect calls: 1 to
shash_digest_unaligned(), 1 to ->init, 2 to ->update ('alignmask + 1'
bytes, then the rest), then 1 to ->final. This is true even if the
algorithm implements ->finup. This is caused by an unnecessary fallback
to code meant to handle unaligned inputs. In fact,
crypto_shash_digest() already does the needed alignment check earlier.
Therefore, optimize the number of indirect calls for aligned inputs to 3
when the algorithm implements ->finup. It remains at 5 when the
algorithm implements neither ->finup nor ->digest.
Similarly, for an shash algorithm that doesn't implement ->finup,
currently crypto_shash_finup() with aligned input makes 4 indirect
calls: 1 to shash_finup_unaligned(), 2 to ->update, and
1 to ->final. Optimize this to 3 calls.
Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>
---
crypto/shash.c | 22 ++++++++++++++++++++--
1 file changed, 20 insertions(+), 2 deletions(-)
diff --git a/crypto/shash.c b/crypto/shash.c
index 1fadb6b59bdcc..d99dc2f94c65f 100644
--- a/crypto/shash.c
+++ b/crypto/shash.c
@@ -184,20 +184,29 @@ int crypto_shash_final(struct shash_desc *desc, u8 *out)
}
EXPORT_SYMBOL_GPL(crypto_shash_final);
static int shash_finup_unaligned(struct shash_desc *desc, const u8 *data,
unsigned int len, u8 *out)
{
return shash_update_unaligned(desc, data, len) ?:
shash_final_unaligned(desc, out);
}
+static int shash_default_finup(struct shash_desc *desc, const u8 *data,
+ unsigned int len, u8 *out)
+{
+ struct shash_alg *shash = crypto_shash_alg(desc->tfm);
+
+ return shash->update(desc, data, len) ?:
+ shash->final(desc, out);
+}
+
int crypto_shash_finup(struct shash_desc *desc, const u8 *data,
unsigned int len, u8 *out)
{
struct crypto_shash *tfm = desc->tfm;
struct shash_alg *shash = crypto_shash_alg(tfm);
unsigned long alignmask = crypto_shash_alignmask(tfm);
int err;
if (IS_ENABLED(CONFIG_CRYPTO_STATS)) {
struct crypto_istat_hash *istat = shash_get_stat(shash);
@@ -217,20 +226,29 @@ int crypto_shash_finup(struct shash_desc *desc, const u8 *data,
EXPORT_SYMBOL_GPL(crypto_shash_finup);
static int shash_digest_unaligned(struct shash_desc *desc, const u8 *data,
unsigned int len, u8 *out)
{
return crypto_shash_init(desc) ?:
shash_update_unaligned(desc, data, len) ?:
shash_final_unaligned(desc, out);
}
+static int shash_default_digest(struct shash_desc *desc, const u8 *data,
+ unsigned int len, u8 *out)
+{
+ struct shash_alg *shash = crypto_shash_alg(desc->tfm);
+
+ return shash->init(desc) ?:
+ shash->finup(desc, data, len, out);
+}
+
int crypto_shash_digest(struct shash_desc *desc, const u8 *data,
unsigned int len, u8 *out)
{
struct crypto_shash *tfm = desc->tfm;
struct shash_alg *shash = crypto_shash_alg(tfm);
unsigned long alignmask = crypto_shash_alignmask(tfm);
int err;
if (IS_ENABLED(CONFIG_CRYPTO_STATS)) {
struct crypto_istat_hash *istat = shash_get_stat(shash);
@@ -649,23 +667,23 @@ static int shash_prepare_alg(struct shash_alg *alg)
return -EINVAL;
err = hash_prepare_alg(&alg->halg);
if (err)
return err;
base->cra_type = &crypto_shash_type;
base->cra_flags |= CRYPTO_ALG_TYPE_SHASH;
if (!alg->finup)
- alg->finup = shash_finup_unaligned;
+ alg->finup = shash_default_finup;
if (!alg->digest)
- alg->digest = shash_digest_unaligned;
+ alg->digest = shash_default_digest;
if (!alg->export) {
alg->export = shash_default_export;
alg->import = shash_default_import;
alg->halg.statesize = alg->descsize;
}
if (!alg->setkey)
alg->setkey = shash_no_setkey;
return 0;
}
--
2.42.0
