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author | Herbert Xu <herbert@gondor.apana.org.au> | 2008-08-31 18:52:18 +1000 |
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committer | Herbert Xu <herbert@gondor.apana.org.au> | 2008-12-25 11:01:28 +1100 |
commit | 3b2f6df08258e2875f42bd630eece7e7241a053b (patch) | |
tree | f46e989b103580a6286d644b3c88892188339e19 /crypto/shash.c | |
parent | 7b5a080b3c46f0cac71c0d0262634c6517d4ee4f (diff) | |
download | lwn-3b2f6df08258e2875f42bd630eece7e7241a053b.tar.gz lwn-3b2f6df08258e2875f42bd630eece7e7241a053b.zip |
crypto: hash - Export shash through ahash
This patch allows shash algorithms to be used through the ahash
interface. This is required before we can convert digest algorithms
over to shash.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'crypto/shash.c')
-rw-r--r-- | crypto/shash.c | 143 |
1 files changed, 143 insertions, 0 deletions
diff --git a/crypto/shash.c b/crypto/shash.c index 82ec4bd8d2f5..3f4c713a21ea 100644 --- a/crypto/shash.c +++ b/crypto/shash.c @@ -10,6 +10,7 @@ * */ +#include <crypto/scatterwalk.h> #include <crypto/internal/hash.h> #include <linux/err.h> #include <linux/kernel.h> @@ -17,11 +18,15 @@ #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 int shash_setkey_unaligned(struct crypto_shash *tfm, const u8 *key, unsigned int keylen) { @@ -167,6 +172,142 @@ int crypto_shash_digest(struct shash_desc *desc, const u8 *data, } EXPORT_SYMBOL_GPL(crypto_shash_digest); +static int shash_async_setkey(struct crypto_ahash *tfm, const u8 *key, + unsigned int keylen) +{ + struct crypto_shash **ctx = crypto_ahash_ctx(tfm); + + return crypto_shash_setkey(*ctx, key, keylen); +} + +static int shash_async_init(struct ahash_request *req) +{ + struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req)); + struct shash_desc *desc = ahash_request_ctx(req); + + desc->tfm = *ctx; + desc->flags = req->base.flags; + + return crypto_shash_init(desc); +} + +static int shash_async_update(struct ahash_request *req) +{ + struct shash_desc *desc = ahash_request_ctx(req); + struct crypto_hash_walk walk; + int nbytes; + + for (nbytes = crypto_hash_walk_first(req, &walk); nbytes > 0; + nbytes = crypto_hash_walk_done(&walk, nbytes)) + nbytes = crypto_shash_update(desc, walk.data, nbytes); + + return nbytes; +} + +static int shash_async_final(struct ahash_request *req) +{ + return crypto_shash_final(ahash_request_ctx(req), req->result); +} + +static int shash_async_digest(struct ahash_request *req) +{ + struct scatterlist *sg = req->src; + unsigned int offset = sg->offset; + unsigned int nbytes = req->nbytes; + int err; + + if (nbytes < min(sg->length, ((unsigned int)(PAGE_SIZE)) - offset)) { + struct crypto_shash **ctx = + crypto_ahash_ctx(crypto_ahash_reqtfm(req)); + struct shash_desc *desc = ahash_request_ctx(req); + void *data; + + desc->tfm = *ctx; + desc->flags = req->base.flags; + + data = crypto_kmap(sg_page(sg), 0); + err = crypto_shash_digest(desc, data + offset, nbytes, + req->result); + crypto_kunmap(data, 0); + crypto_yield(desc->flags); + goto out; + } + + err = shash_async_init(req); + if (err) + goto out; + + err = shash_async_update(req); + if (err) + goto out; + + err = shash_async_final(req); + +out: + return err; +} + +static void crypto_exit_shash_ops_async(struct crypto_tfm *tfm) +{ + struct crypto_shash **ctx = crypto_tfm_ctx(tfm); + + crypto_free_shash(*ctx); +} + +static int crypto_init_shash_ops_async(struct crypto_tfm *tfm) +{ + struct crypto_alg *calg = tfm->__crt_alg; + struct shash_alg *alg = __crypto_shash_alg(calg); + struct ahash_tfm *crt = &tfm->crt_ahash; + struct crypto_shash **ctx = crypto_tfm_ctx(tfm); + struct crypto_shash *shash; + + if (!crypto_mod_get(calg)) + return -EAGAIN; + + shash = __crypto_shash_cast(crypto_create_tfm( + calg, &crypto_shash_type)); + if (IS_ERR(shash)) { + crypto_mod_put(calg); + return PTR_ERR(shash); + } + + *ctx = shash; + tfm->exit = crypto_exit_shash_ops_async; + + crt->init = shash_async_init; + crt->update = shash_async_update; + crt->final = shash_async_final; + crt->digest = shash_async_digest; + crt->setkey = shash_async_setkey; + + crt->digestsize = alg->digestsize; + crt->reqsize = sizeof(struct shash_desc) + crypto_shash_descsize(shash); + + return 0; +} + +static int crypto_init_shash_ops(struct crypto_tfm *tfm, u32 type, u32 mask) +{ + switch (mask & CRYPTO_ALG_TYPE_MASK) { + case CRYPTO_ALG_TYPE_AHASH_MASK: + return crypto_init_shash_ops_async(tfm); + } + + return -EINVAL; +} + +static unsigned int crypto_shash_ctxsize(struct crypto_alg *alg, u32 type, + u32 mask) +{ + switch (mask & CRYPTO_ALG_TYPE_MASK) { + case CRYPTO_ALG_TYPE_AHASH_MASK: + return sizeof(struct crypto_shash *); + } + + return 0; +} + static int crypto_shash_init_tfm(struct crypto_tfm *tfm, const struct crypto_type *frontend) { @@ -194,7 +335,9 @@ static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg) } static const struct crypto_type crypto_shash_type = { + .ctxsize = crypto_shash_ctxsize, .extsize = crypto_shash_extsize, + .init = crypto_init_shash_ops, .init_tfm = crypto_shash_init_tfm, #ifdef CONFIG_PROC_FS .show = crypto_shash_show, |