static struct shash_desc *chcr_alloc_shash(unsigned int ds)
{
struct crypto_shash *base_hash = NULL;
struct shash_desc *desc;
switch (ds) {
case SHA1_DIGEST_SIZE:
base_hash = crypto_alloc_shash("sha1-generic", 0, 0);
break;
case SHA224_DIGEST_SIZE:
base_hash = crypto_alloc_shash("sha224-generic", 0, 0);
break;
case SHA256_DIGEST_SIZE:
base_hash = crypto_alloc_shash("sha256-generic", 0, 0);
break;
case SHA384_DIGEST_SIZE:
base_hash = crypto_alloc_shash("sha384-generic", 0, 0);
break;
case SHA512_DIGEST_SIZE:
base_hash = crypto_alloc_shash("sha512-generic", 0, 0);
break;
}
if (IS_ERR(base_hash)) {
pr_err("Can not allocate sha-generic algo.\n");
return (void *)base_hash;
}
desc = kmalloc(sizeof(*desc) + crypto_shash_descsize(base_hash),
GFP_KERNEL);
if (!desc)
return ERR_PTR(-ENOMEM);
desc->tfm = base_hash;
desc->flags = crypto_shash_get_flags(base_hash);
return desc;
}
static int p8_ghash_init_tfm(struct crypto_tfm *tfm)
{
const char *alg;
struct crypto_shash *fallback;
struct crypto_shash *shash_tfm = __crypto_shash_cast(tfm);
struct p8_ghash_ctx *ctx = crypto_tfm_ctx(tfm);
if (!(alg = crypto_tfm_alg_name(tfm))) {
printk(KERN_ERR "Failed to get algorithm name.\n");
return -ENOENT;
}
fallback = crypto_alloc_shash(alg, 0 ,CRYPTO_ALG_NEED_FALLBACK);
if (IS_ERR(fallback)) {
printk(KERN_ERR "Failed to allocate transformation for '%s': %ld\n",
alg, PTR_ERR(fallback));
return PTR_ERR(fallback);
}
printk(KERN_INFO "Using '%s' as fallback implementation.\n",
crypto_tfm_alg_driver_name(crypto_shash_tfm(fallback)));
crypto_shash_set_flags(fallback,
crypto_shash_get_flags((struct crypto_shash *) tfm));
ctx->fallback = fallback;
shash_tfm->descsize = sizeof(struct p8_ghash_desc_ctx)
+ crypto_shash_descsize(fallback);
return 0;
}
