crypto: api - Fix crypto_alloc_tfm/create_create_tfm return convention

This is based on a report and patch by Geert Uytterhoeven.

The functions crypto_alloc_tfm and create_create_tfm return a
pointer that needs to be adjusted by the caller when successful
and otherwise an error value.  This means that the caller has
to check for the error and only perform the adjustment if the
pointer returned is valid.

Since all callers want to make the adjustment and we know how
to adjust it ourselves, it's much easier to just return adjusted
pointer directly.

The only caveat is that we have to return a void * instead of
struct crypto_tfm *.  However, this isn't that bad because both
of these functions are for internal use only (by types code like
shash.c, not even algorithms code).

This patch also moves crypto_alloc_tfm into crypto/internal.h
(crypto_create_tfm is already there) to reflect this.

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

diff --git a/crypto/api.c b/crypto/api.c
index 56b6e0e6631172f4f4bfde6b563bd936ae326a97..22385cac90bb8f8e3e338c06f0d105e079003d2c 100644 (file)
--- a/crypto/api.c
+++ b/crypto/api.c
@@ -453,8 +453,8 @@ err:
 }
 EXPORT_SYMBOL_GPL(crypto_alloc_base);
 
-struct crypto_tfm *crypto_create_tfm(struct crypto_alg *alg,
-                                    const struct crypto_type *frontend)
+void *crypto_create_tfm(struct crypto_alg *alg,
+                       const struct crypto_type *frontend)
 {
        char *mem;
        struct crypto_tfm *tfm = NULL;
@@ -488,9 +488,9 @@ out_free_tfm:
                crypto_shoot_alg(alg);
        kfree(mem);
 out_err:
-       tfm = ERR_PTR(err);
+       mem = ERR_PTR(err);
 out:
-       return tfm;
+       return mem;
 }
 EXPORT_SYMBOL_GPL(crypto_create_tfm);
 
@@ -514,12 +514,11 @@ EXPORT_SYMBOL_GPL(crypto_create_tfm);
  *
  *     In case of error the return value is an error pointer.
  */
-struct crypto_tfm *crypto_alloc_tfm(const char *alg_name,
-                                   const struct crypto_type *frontend,
-                                   u32 type, u32 mask)
+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);
-       struct crypto_tfm *tfm;
+       void *tfm;
        int err;
 
        type &= frontend->maskclear;

diff --git a/crypto/internal.h b/crypto/internal.h
index 3c19a27a7563cd628513a777a59121a24caadf85..fc76e1f37fc35d0fd4928ec9326b330c22937d53 100644 (file)
--- a/crypto/internal.h
+++ b/crypto/internal.h
@@ -109,8 +109,10 @@ void crypto_alg_tested(const char *name, int err);
 void crypto_shoot_alg(struct crypto_alg *alg);
 struct crypto_tfm *__crypto_alloc_tfm(struct crypto_alg *alg, u32 type,
                                      u32 mask);
-struct crypto_tfm *crypto_create_tfm(struct crypto_alg *alg,
-                                    const struct crypto_type *frontend);
+void *crypto_create_tfm(struct crypto_alg *alg,
+                       const struct crypto_type *frontend);
+void *crypto_alloc_tfm(const char *alg_name,
+                      const struct crypto_type *frontend, u32 type, u32 mask);
 
 int crypto_register_instance(struct crypto_template *tmpl,
                             struct crypto_instance *inst);

diff --git a/crypto/shash.c b/crypto/shash.c
index 13a0dc150a4d3741a6958b5ae59611d621925be9..7a659733f94a4e1087fabcfc8d5e48fd6c5c4521 100644 (file)
--- a/crypto/shash.c
+++ b/crypto/shash.c
@@ -18,15 +18,10 @@
 #include <linux/slab.h>
 #include <linux/seq_file.h>
 
-static const struct crypto_type crypto_shash_type;
-
-static inline struct crypto_shash *__crypto_shash_cast(struct crypto_tfm *tfm)
-{
-       return container_of(tfm, struct crypto_shash, base);
-}
-
 #include "internal.h"
 
+static const struct crypto_type crypto_shash_type;
+
 static int shash_setkey_unaligned(struct crypto_shash *tfm, const u8 *key,
                                  unsigned int keylen)
 {
@@ -282,8 +277,7 @@ static int crypto_init_shash_ops_async(struct crypto_tfm *tfm)
        if (!crypto_mod_get(calg))
                return -EAGAIN;
 
-       shash = __crypto_shash_cast(crypto_create_tfm(
-               calg, &crypto_shash_type));
+       shash = crypto_create_tfm(calg, &crypto_shash_type);
        if (IS_ERR(shash)) {
                crypto_mod_put(calg);
                return PTR_ERR(shash);
@@ -391,8 +385,7 @@ static int crypto_init_shash_ops_compat(struct crypto_tfm *tfm)
        if (!crypto_mod_get(calg))
                return -EAGAIN;
 
-       shash = __crypto_shash_cast(crypto_create_tfm(
-               calg, &crypto_shash_type));
+       shash = crypto_create_tfm(calg, &crypto_shash_type);
        if (IS_ERR(shash)) {
                crypto_mod_put(calg);
                return PTR_ERR(shash);
@@ -480,8 +473,7 @@ static const struct crypto_type crypto_shash_type = {
 struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type,
                                        u32 mask)
 {
-       return __crypto_shash_cast(
-               crypto_alloc_tfm(alg_name, &crypto_shash_type, type, mask));
+       return crypto_alloc_tfm(alg_name, &crypto_shash_type, type, mask);
 }
 EXPORT_SYMBOL_GPL(crypto_alloc_shash);
 

diff --git a/include/linux/crypto.h b/include/linux/crypto.h
index 1f2e9020acc667d5f0dd0f2e501e6f85f0fff140..29729b834380737fa96448e510ce98f1440f41fa 100644 (file)
--- a/include/linux/crypto.h
+++ b/include/linux/crypto.h
@@ -548,9 +548,6 @@ struct crypto_attr_u32 {
  * Transform user interface.
  */
  
-struct crypto_tfm *crypto_alloc_tfm(const char *alg_name,
-                                   const struct crypto_type *frontend,
-                                   u32 type, u32 mask);
 struct crypto_tfm *crypto_alloc_base(const char *alg_name, u32 type, u32 mask);
 void crypto_destroy_tfm(void *mem, struct crypto_tfm *tfm);