[CRYPTO] api: Allow algorithm lookup by type
This patch also adds the infrastructure to pick an algorithm based on
their type. For example, this allows you to select the encryption
algorithm "aes", instead of any algorithm registered under the name
"aes". For now this is only accessible internally. Eventually it
will be made available through crypto_alloc_tfm.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/crypto/api.c b/crypto/api.c
index 67cd6f8..ddf6a76 100644
--- a/crypto/api.c
+++ b/crypto/api.c
@@ -57,7 +57,7 @@
}
EXPORT_SYMBOL_GPL(crypto_mod_put);
-struct crypto_alg *__crypto_alg_lookup(const char *name)
+struct crypto_alg *__crypto_alg_lookup(const char *name, u32 type, u32 mask)
{
struct crypto_alg *q, *alg = NULL;
int best = -2;
@@ -65,6 +65,13 @@
list_for_each_entry(q, &crypto_alg_list, cra_list) {
int exact, fuzzy;
+ if ((q->cra_flags ^ type) & mask)
+ continue;
+
+ if (crypto_is_larval(q) &&
+ ((struct crypto_larval *)q)->mask != mask)
+ continue;
+
exact = !strcmp(q->cra_driver_name, name);
fuzzy = !strcmp(q->cra_name, name);
if (!exact && !(fuzzy && q->cra_priority > best))
@@ -96,7 +103,8 @@
kfree(larval);
}
-static struct crypto_alg *crypto_larval_alloc(const char *name)
+static struct crypto_alg *crypto_larval_alloc(const char *name, u32 type,
+ u32 mask)
{
struct crypto_alg *alg;
struct crypto_larval *larval;
@@ -105,7 +113,8 @@
if (!larval)
return NULL;
- larval->alg.cra_flags = CRYPTO_ALG_LARVAL;
+ larval->mask = mask;
+ larval->alg.cra_flags = CRYPTO_ALG_LARVAL | type;
larval->alg.cra_priority = -1;
larval->alg.cra_destroy = crypto_larval_destroy;
@@ -114,7 +123,7 @@
init_completion(&larval->completion);
down_write(&crypto_alg_sem);
- alg = __crypto_alg_lookup(name);
+ alg = __crypto_alg_lookup(name, type, mask);
if (!alg) {
alg = &larval->alg;
list_add(&alg->cra_list, &crypto_alg_list);
@@ -151,7 +160,8 @@
return alg;
}
-static struct crypto_alg *crypto_alg_lookup(const char *name)
+static struct crypto_alg *crypto_alg_lookup(const char *name, u32 type,
+ u32 mask)
{
struct crypto_alg *alg;
@@ -159,25 +169,27 @@
return NULL;
down_read(&crypto_alg_sem);
- alg = __crypto_alg_lookup(name);
+ alg = __crypto_alg_lookup(name, type, mask);
up_read(&crypto_alg_sem);
return alg;
}
-/* A far more intelligent version of this is planned. For now, just
- * try an exact match on the name of the algorithm. */
-static struct crypto_alg *crypto_alg_mod_lookup(const char *name)
+struct crypto_alg *crypto_alg_mod_lookup(const char *name, u32 type, u32 mask)
{
struct crypto_alg *alg;
struct crypto_alg *larval;
int ok;
- alg = try_then_request_module(crypto_alg_lookup(name), name);
+ mask &= ~CRYPTO_ALG_LARVAL;
+ type &= mask;
+
+ alg = try_then_request_module(crypto_alg_lookup(name, type, mask),
+ name);
if (alg)
return crypto_is_larval(alg) ? crypto_larval_wait(alg) : alg;
- larval = crypto_larval_alloc(name);
+ larval = crypto_larval_alloc(name, type, mask);
if (!larval || !crypto_is_larval(larval))
return larval;
@@ -196,6 +208,7 @@
crypto_larval_kill(larval);
return alg;
}
+EXPORT_SYMBOL_GPL(crypto_alg_mod_lookup);
static int crypto_init_flags(struct crypto_tfm *tfm, u32 flags)
{
@@ -291,7 +304,7 @@
struct crypto_alg *alg;
unsigned int tfm_size;
- alg = crypto_alg_mod_lookup(name);
+ alg = crypto_alg_mod_lookup(name, 0, 0);
if (alg == NULL)
goto out;
@@ -346,7 +359,7 @@
int crypto_alg_available(const char *name, u32 flags)
{
int ret = 0;
- struct crypto_alg *alg = crypto_alg_mod_lookup(name);
+ struct crypto_alg *alg = crypto_alg_mod_lookup(name, 0, 0);
if (alg) {
crypto_mod_put(alg);