crypto: api - Add crypto_attr_alg2 helper

This patch adds the helper crypto_attr_alg2 which is similar to
crypto_attr_alg but takes an extra frontend argument.  This is
intended to be used by new style algorithm types such as shash.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 22 insertions, 9 deletions

diff --git a/crypto/api.c b/crypto/api.c
index d5944f92b416..ba81221b3bef 100644
--- a/crypto/api.c
+++ b/crypto/api.c
@@ -503,6 +503,27 @@ out:
 }
 EXPORT_SYMBOL_GPL(crypto_create_tfm);
 
+struct crypto_alg *crypto_find_alg(const char *alg_name,
+                                   const struct crypto_type *frontend,
+                                   u32 type, u32 mask)
+{
+        struct crypto_alg *(*lookup)(const char *name, u32 type, u32 mask) =
+                crypto_alg_mod_lookup;
+
+        if (frontend) {
+                type &= frontend->maskclear;
+                mask &= frontend->maskclear;
+                type |= frontend->type;
+                mask |= frontend->maskset;
+
+                if (frontend->lookup)
+                        lookup = frontend->lookup;
+        }
+
+        return lookup(alg_name, type, mask);
+}
+EXPORT_SYMBOL_GPL(crypto_find_alg);
+
 /*
  *      crypto_alloc_tfm - Locate algorithm and allocate transform
  *      @alg_name: Name of algorithm
@@ -526,21 +547,13 @@ EXPORT_SYMBOL_GPL(crypto_create_tfm);
 void *crypto_alloc_tfm(const char *alg_name,
                        const struct crypto_type *frontend, u32 type, u32 mask)
 {
-        struct crypto_alg *(*lookup)(const char *name, u32 type, u32 mask);
         void *tfm;
         int err;
 
-        type &= frontend->maskclear;
-        mask &= frontend->maskclear;
-        type |= frontend->type;
-        mask |= frontend->maskset;
-
-        lookup = frontend->lookup ?: crypto_alg_mod_lookup;
-
         for (;;) {
                 struct crypto_alg *alg;
 
-                alg = lookup(alg_name, type, mask);
+                alg = crypto_find_alg(alg_name, frontend, type, mask);
                 if (IS_ERR(alg)) {
                         err = PTR_ERR(alg);
                         goto err;