Techwizz/kernel-fxtec-pro1x
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

crypto: hash - Add import/export interface

Browse source 
It is often useful to save the partial state of a hash function
so that it can be used as a base for two or more computations.

The most prominent example is HMAC where all hashes start from
a base determined by the key.  Having an import/export interface
means that we only have to compute that base once rather than
for each message.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Herbert Xu 2008-11-02 21:38:11 +08:00
parent 3b2f6df082
commit dec8b78606
5 changed files with 50 additions and 5 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

14
crypto/ahash.c
View file

@ -146,6 +146,20 @@ static int ahash_setkey(struct crypto_ahash *tfm, const u8 *key,
return ahash->setkey(tfm, key, keylen);
}
int crypto_ahash_import(struct ahash_request *req, const u8 *in)
{
struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
struct ahash_alg *alg = crypto_ahash_alg(tfm);
memcpy(ahash_request_ctx(req), in, crypto_ahash_reqsize(tfm));
if (alg->reinit)
alg->reinit(req);
return 0;
}
EXPORT_SYMBOL_GPL(crypto_ahash_import);
static unsigned int crypto_ahash_ctxsize(struct crypto_alg *alg, u32 type,
u32 mask)
{

14
crypto/shash.c
View file

@ -172,6 +172,20 @@ int crypto_shash_digest(struct shash_desc *desc, const u8 *data,
}
EXPORT_SYMBOL_GPL(crypto_shash_digest);
int crypto_shash_import(struct shash_desc *desc, const u8 *in)
{
struct crypto_shash *tfm = desc->tfm;
struct shash_alg *alg = crypto_shash_alg(tfm);
memcpy(shash_desc_ctx(desc), in, crypto_shash_descsize(tfm));
if (alg->reinit)
alg->reinit(desc);
return 0;
}
EXPORT_SYMBOL_GPL(crypto_shash_import);
static int shash_async_setkey(struct crypto_ahash *tfm, const u8 *key,
unsigned int keylen)
{

21
include/crypto/hash.h
View file

@ -24,6 +24,7 @@ struct shash_desc {
struct shash_alg {
int (*init)(struct shash_desc *desc);
int (*reinit)(struct shash_desc *desc);
int (*update)(struct shash_desc *desc, const u8 *data,
unsigned int len);
int (*final)(struct shash_desc *desc, u8 *out);
@ -116,6 +117,11 @@ static inline unsigned int crypto_ahash_reqsize(struct crypto_ahash *tfm)
return crypto_ahash_crt(tfm)->reqsize;
}
static inline void *ahash_request_ctx(struct ahash_request *req)
{
return req->__ctx;
}
static inline int crypto_ahash_setkey(struct crypto_ahash *tfm,
const u8 *key, unsigned int keylen)
{
@ -130,6 +136,14 @@ static inline int crypto_ahash_digest(struct ahash_request *req)
return crt->digest(req);
}
static inline void crypto_ahash_export(struct ahash_request *req, u8 *out)
{
memcpy(out, ahash_request_ctx(req),
crypto_ahash_reqsize(crypto_ahash_reqtfm(req)));
}
int crypto_ahash_import(struct ahash_request *req, const u8 *in);
static inline int crypto_ahash_init(struct ahash_request *req)
{
struct ahash_tfm *crt = crypto_ahash_crt(crypto_ahash_reqtfm(req));
@ -262,6 +276,13 @@ int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key,
int crypto_shash_digest(struct shash_desc *desc, const u8 *data,
unsigned int len, u8 *out);
static inline void crypto_shash_export(struct shash_desc *desc, u8 *out)
{
memcpy(out, shash_desc_ctx(desc), crypto_shash_descsize(desc->tfm));
}
int crypto_shash_import(struct shash_desc *desc, const u8 *in);
static inline int crypto_shash_init(struct shash_desc *desc)
{
return crypto_shash_alg(desc->tfm)->init(desc);

5
include/crypto/internal/hash.h
View file

@ -66,11 +66,6 @@ static inline struct ahash_request *ahash_dequeue_request(
return ahash_request_cast(crypto_dequeue_request(queue));
}
static inline void *ahash_request_ctx(struct ahash_request *req)
{
return req->__ctx;
}
static inline int ahash_tfm_in_queue(struct crypto_queue *queue,
struct crypto_ahash *tfm)
{

1
include/linux/crypto.h
View file

@ -221,6 +221,7 @@ struct ablkcipher_alg {
struct ahash_alg {
int (*init)(struct ahash_request *req);
int (*reinit)(struct ahash_request *req);
int (*update)(struct ahash_request *req);
int (*final)(struct ahash_request *req);
int (*digest)(struct ahash_request *req);