crypto: shash - Make descsize a run-time attribute
Herbert Xu [Tue, 14 Jul 2009 04:50:12 +0000 (12:50 +0800)]
This patch changes descsize to a run-time attribute so that
implementations can change it in their init functions.

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

crypto/shash.c
include/crypto/hash.h
include/crypto/internal/hash.h

index 131e14d..d8e0f8f 100644 (file)
@@ -300,14 +300,16 @@ static int crypto_init_shash_ops_async(struct crypto_tfm *tfm)
 static int shash_compat_setkey(struct crypto_hash *tfm, const u8 *key,
                               unsigned int keylen)
 {
-       struct shash_desc *desc = crypto_hash_ctx(tfm);
+       struct shash_desc **descp = crypto_hash_ctx(tfm);
+       struct shash_desc *desc = *descp;
 
        return crypto_shash_setkey(desc->tfm, key, keylen);
 }
 
 static int shash_compat_init(struct hash_desc *hdesc)
 {
-       struct shash_desc *desc = crypto_hash_ctx(hdesc->tfm);
+       struct shash_desc **descp = crypto_hash_ctx(hdesc->tfm);
+       struct shash_desc *desc = *descp;
 
        desc->flags = hdesc->flags;
 
@@ -317,7 +319,8 @@ static int shash_compat_init(struct hash_desc *hdesc)
 static int shash_compat_update(struct hash_desc *hdesc, struct scatterlist *sg,
                               unsigned int len)
 {
-       struct shash_desc *desc = crypto_hash_ctx(hdesc->tfm);
+       struct shash_desc **descp = crypto_hash_ctx(hdesc->tfm);
+       struct shash_desc *desc = *descp;
        struct crypto_hash_walk walk;
        int nbytes;
 
@@ -330,7 +333,9 @@ static int shash_compat_update(struct hash_desc *hdesc, struct scatterlist *sg,
 
 static int shash_compat_final(struct hash_desc *hdesc, u8 *out)
 {
-       return crypto_shash_final(crypto_hash_ctx(hdesc->tfm), out);
+       struct shash_desc **descp = crypto_hash_ctx(hdesc->tfm);
+
+       return crypto_shash_final(*descp, out);
 }
 
 static int shash_compat_digest(struct hash_desc *hdesc, struct scatterlist *sg,
@@ -340,7 +345,8 @@ static int shash_compat_digest(struct hash_desc *hdesc, struct scatterlist *sg,
        int err;
 
        if (nbytes < min(sg->length, ((unsigned int)(PAGE_SIZE)) - offset)) {
-               struct shash_desc *desc = crypto_hash_ctx(hdesc->tfm);
+               struct shash_desc **descp = crypto_hash_ctx(hdesc->tfm);
+               struct shash_desc *desc = *descp;
                void *data;
 
                desc->flags = hdesc->flags;
@@ -368,9 +374,11 @@ out:
 
 static void crypto_exit_shash_ops_compat(struct crypto_tfm *tfm)
 {
-       struct shash_desc *desc= crypto_tfm_ctx(tfm);
+       struct shash_desc **descp = crypto_tfm_ctx(tfm);
+       struct shash_desc *desc = *descp;
 
        crypto_free_shash(desc->tfm);
+       kzfree(desc);
 }
 
 static int crypto_init_shash_ops_compat(struct crypto_tfm *tfm)
@@ -378,8 +386,9 @@ static int crypto_init_shash_ops_compat(struct crypto_tfm *tfm)
        struct hash_tfm *crt = &tfm->crt_hash;
        struct crypto_alg *calg = tfm->__crt_alg;
        struct shash_alg *alg = __crypto_shash_alg(calg);
-       struct shash_desc *desc = crypto_tfm_ctx(tfm);
+       struct shash_desc **descp = crypto_tfm_ctx(tfm);
        struct crypto_shash *shash;
+       struct shash_desc *desc;
 
        if (!crypto_mod_get(calg))
                return -EAGAIN;
@@ -390,6 +399,14 @@ static int crypto_init_shash_ops_compat(struct crypto_tfm *tfm)
                return PTR_ERR(shash);
        }
 
+       desc = kmalloc(sizeof(*desc) + crypto_shash_descsize(shash),
+                      GFP_KERNEL);
+       if (!desc) {
+               crypto_free_shash(shash);
+               return -ENOMEM;
+       }
+
+       *descp = desc;
        desc->tfm = shash;
        tfm->exit = crypto_exit_shash_ops_compat;
 
@@ -419,11 +436,9 @@ static int crypto_init_shash_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
 static unsigned int crypto_shash_ctxsize(struct crypto_alg *alg, u32 type,
                                         u32 mask)
 {
-       struct shash_alg *salg = __crypto_shash_alg(alg);
-
        switch (mask & CRYPTO_ALG_TYPE_MASK) {
        case CRYPTO_ALG_TYPE_HASH_MASK:
-               return sizeof(struct shash_desc) + salg->descsize;
+               return sizeof(struct shash_desc *);
        case CRYPTO_ALG_TYPE_AHASH_MASK:
                return sizeof(struct crypto_shash *);
        }
@@ -434,6 +449,9 @@ static unsigned int crypto_shash_ctxsize(struct crypto_alg *alg, u32 type,
 static int crypto_shash_init_tfm(struct crypto_tfm *tfm,
                                 const struct crypto_type *frontend)
 {
+       struct crypto_shash *hash = __crypto_shash_cast(tfm);
+
+       hash->descsize = crypto_shash_alg(hash)->descsize;
        return 0;
 }
 
@@ -452,7 +470,6 @@ static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg)
        seq_printf(m, "type         : shash\n");
        seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
        seq_printf(m, "digestsize   : %u\n", salg->digestsize);
-       seq_printf(m, "descsize     : %u\n", salg->descsize);
 }
 
 static const struct crypto_type crypto_shash_type = {
index f74214a..fcc02d9 100644 (file)
@@ -48,6 +48,7 @@ struct crypto_ahash {
 };
 
 struct crypto_shash {
+       unsigned int descsize;
        struct crypto_tfm base;
 };
 
@@ -275,7 +276,7 @@ static inline void crypto_shash_clear_flags(struct crypto_shash *tfm, u32 flags)
 
 static inline unsigned int crypto_shash_descsize(struct crypto_shash *tfm)
 {
-       return crypto_shash_alg(tfm)->descsize;
+       return tfm->descsize;
 }
 
 static inline void *shash_desc_ctx(struct shash_desc *desc)
index 069b93e..2d1b10f 100644 (file)
@@ -135,7 +135,7 @@ static inline void *crypto_shash_ctx_aligned(struct crypto_shash *tfm)
 
 static inline struct crypto_shash *__crypto_shash_cast(struct crypto_tfm *tfm)
 {
-       return (struct crypto_shash *)tfm;
+       return container_of(tfm, struct crypto_shash, base);
 }
 
 #endif /* _CRYPTO_INTERNAL_HASH_H */