*
* This module file is a wrapper to invoke the lib/crc32c routines.
*
+ * Copyright (c) 2008 Herbert Xu <herbert@gondor.apana.org.au>
+ *
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation; either version 2 of the License, or (at your option)
* any later version.
*
*/
+
+#include <crypto/internal/hash.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/string.h>
-#include <linux/crypto.h>
#include <linux/crc32c.h>
-#include <linux/types.h>
-#include <asm/byteorder.h>
+#include <linux/kernel.h>
-#define CHKSUM_BLOCK_SIZE 32
+#define CHKSUM_BLOCK_SIZE 1
#define CHKSUM_DIGEST_SIZE 4
struct chksum_ctx {
u32 crc;
+ u32 key;
};
/*
{
struct chksum_ctx *mctx = crypto_tfm_ctx(tfm);
- mctx->crc = ~(u32)0; /* common usage */
+ mctx->crc = mctx->key;
}
/*
* the seed.
*/
static int chksum_setkey(struct crypto_tfm *tfm, const u8 *key,
- unsigned int keylen, u32 *flags)
+ unsigned int keylen)
{
struct chksum_ctx *mctx = crypto_tfm_ctx(tfm);
if (keylen != sizeof(mctx->crc)) {
- if (flags)
- *flags = CRYPTO_TFM_RES_BAD_KEY_LEN;
+ tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
return -EINVAL;
}
- mctx->crc = __cpu_to_le32(*(u32 *)key);
+ mctx->key = le32_to_cpu(*(__le32 *)key);
return 0;
}
unsigned int length)
{
struct chksum_ctx *mctx = crypto_tfm_ctx(tfm);
- u32 mcrc;
- mcrc = crc32c(mctx->crc, data, (size_t)length);
-
- mctx->crc = mcrc;
+ mctx->crc = crc32c(mctx->crc, data, length);
}
static void chksum_final(struct crypto_tfm *tfm, u8 *out)
{
struct chksum_ctx *mctx = crypto_tfm_ctx(tfm);
- u32 mcrc = (mctx->crc ^ ~(u32)0);
- *(u32 *)out = __le32_to_cpu(mcrc);
+ *(__le32 *)out = ~cpu_to_le32(mctx->crc);
}
-static struct crypto_alg alg = {
+static int crc32c_cra_init_old(struct crypto_tfm *tfm)
+{
+ struct chksum_ctx *mctx = crypto_tfm_ctx(tfm);
+
+ mctx->key = ~0;
+ return 0;
+}
+
+static struct crypto_alg old_alg = {
.cra_name = "crc32c",
.cra_flags = CRYPTO_ALG_TYPE_DIGEST,
.cra_blocksize = CHKSUM_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct chksum_ctx),
.cra_module = THIS_MODULE,
- .cra_list = LIST_HEAD_INIT(alg.cra_list),
+ .cra_list = LIST_HEAD_INIT(old_alg.cra_list),
+ .cra_init = crc32c_cra_init_old,
.cra_u = {
.digest = {
.dia_digestsize= CHKSUM_DIGEST_SIZE,
}
};
-static int __init init(void)
+/*
+ * Setting the seed allows arbitrary accumulators and flexible XOR policy
+ * If your algorithm starts with ~0, then XOR with ~0 before you set
+ * the seed.
+ */
+static int crc32c_setkey(struct crypto_ahash *hash, const u8 *key,
+ unsigned int keylen)
+{
+ u32 *mctx = crypto_ahash_ctx(hash);
+
+ if (keylen != sizeof(u32)) {
+ crypto_ahash_set_flags(hash, CRYPTO_TFM_RES_BAD_KEY_LEN);
+ return -EINVAL;
+ }
+ *mctx = le32_to_cpup((__le32 *)key);
+ return 0;
+}
+
+static int crc32c_init(struct ahash_request *req)
{
- return crypto_register_alg(&alg);
+ u32 *mctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
+ u32 *crcp = ahash_request_ctx(req);
+
+ *crcp = *mctx;
+ return 0;
+}
+
+static int crc32c_update(struct ahash_request *req)
+{
+ struct crypto_hash_walk walk;
+ u32 *crcp = ahash_request_ctx(req);
+ u32 crc = *crcp;
+ int nbytes;
+
+ for (nbytes = crypto_hash_walk_first(req, &walk); nbytes;
+ nbytes = crypto_hash_walk_done(&walk, 0))
+ crc = crc32c(crc, walk.data, nbytes);
+
+ *crcp = crc;
+ return 0;
+}
+
+static int crc32c_final(struct ahash_request *req)
+{
+ u32 *crcp = ahash_request_ctx(req);
+
+ *(__le32 *)req->result = ~cpu_to_le32p(crcp);
+ return 0;
+}
+
+static int crc32c_digest(struct ahash_request *req)
+{
+ struct crypto_hash_walk walk;
+ u32 *mctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
+ u32 crc = *mctx;
+ int nbytes;
+
+ for (nbytes = crypto_hash_walk_first(req, &walk); nbytes;
+ nbytes = crypto_hash_walk_done(&walk, 0))
+ crc = crc32c(crc, walk.data, nbytes);
+
+ *(__le32 *)req->result = ~cpu_to_le32(crc);
+ return 0;
+}
+
+static int crc32c_cra_init(struct crypto_tfm *tfm)
+{
+ u32 *key = crypto_tfm_ctx(tfm);
+
+ *key = ~0;
+
+ tfm->crt_ahash.reqsize = sizeof(u32);
+
+ return 0;
+}
+
+static struct crypto_alg alg = {
+ .cra_name = "crc32c",
+ .cra_driver_name = "crc32c-generic",
+ .cra_priority = 100,
+ .cra_flags = CRYPTO_ALG_TYPE_AHASH,
+ .cra_blocksize = CHKSUM_BLOCK_SIZE,
+ .cra_alignmask = 3,
+ .cra_ctxsize = sizeof(u32),
+ .cra_module = THIS_MODULE,
+ .cra_list = LIST_HEAD_INIT(alg.cra_list),
+ .cra_init = crc32c_cra_init,
+ .cra_type = &crypto_ahash_type,
+ .cra_u = {
+ .ahash = {
+ .digestsize = CHKSUM_DIGEST_SIZE,
+ .setkey = crc32c_setkey,
+ .init = crc32c_init,
+ .update = crc32c_update,
+ .final = crc32c_final,
+ .digest = crc32c_digest,
+ }
+ }
+};
+
+static int __init crc32c_mod_init(void)
+{
+ int err;
+
+ err = crypto_register_alg(&old_alg);
+ if (err)
+ return err;
+
+ err = crypto_register_alg(&alg);
+ if (err)
+ crypto_unregister_alg(&old_alg);
+
+ return err;
}
-static void __exit fini(void)
+static void __exit crc32c_mod_fini(void)
{
crypto_unregister_alg(&alg);
+ crypto_unregister_alg(&old_alg);
}
-module_init(init);
-module_exit(fini);
+module_init(crc32c_mod_init);
+module_exit(crc32c_mod_fini);
MODULE_AUTHOR("Clay Haapala <chaapala@cisco.com>");
MODULE_DESCRIPTION("CRC32c (Castagnoli) calculations wrapper for lib/crc32c");
git.openpandora.org / pandora-kernel.git / blobdiff