crypto: crc32 - Rename generic implementation

The generic crc32 implementation is currently called crc32.  This
is a problem because it clashes with the lib implementation of crc32.

This patch renames the crypto crc32 to crc32_generic so that it is
consistent with crc32c.  An alias for the driver is also added.

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

1 files changed, 160 insertions, 0 deletions

diff --git a/crypto/crc32_generic.c b/crypto/crc32_generic.c
new file mode 100644
index 000000000000..aa2a25fc7482
--- /dev/null
+++ b/crypto/crc32_generic.c
@@ -0,0 +1,160 @@
+/* GPL HEADER START
+ *
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 only,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License version 2 for more details (a copy is included
+ * in the LICENSE file that accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License
+ * version 2 along with this program; If not, see http://www.gnu.org/licenses
+ *
+ * Please  visit http://www.xyratex.com/contact if you need additional
+ * information or have any questions.
+ *
+ * GPL HEADER END
+ */
+
+/*
+ * Copyright 2012 Xyratex Technology Limited
+ */
+
+/*
+ * This is crypto api shash wrappers to crc32_le.
+ */
+
+#include <linux/crc32.h>
+#include <crypto/internal/hash.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/kernel.h>
+
+#define CHKSUM_BLOCK_SIZE	1
+#define CHKSUM_DIGEST_SIZE	4
+
+static u32 __crc32_le(u32 crc, unsigned char const *p, size_t len)
+{
+	return crc32_le(crc, p, len);
+}
+
+/** No default init with ~0 */
+static int crc32_cra_init(struct crypto_tfm *tfm)
+{
+	u32 *key = crypto_tfm_ctx(tfm);
+
+	*key = 0;
+
+	return 0;
+}
+
+
+/*
+ * 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 crc32_setkey(struct crypto_shash *hash, const u8 *key,
+			unsigned int keylen)
+{
+	u32 *mctx = crypto_shash_ctx(hash);
+
+	if (keylen != sizeof(u32)) {
+		crypto_shash_set_flags(hash, CRYPTO_TFM_RES_BAD_KEY_LEN);
+		return -EINVAL;
+	}
+	*mctx = le32_to_cpup((__le32 *)key);
+	return 0;
+}
+
+static int crc32_init(struct shash_desc *desc)
+{
+	u32 *mctx = crypto_shash_ctx(desc->tfm);
+	u32 *crcp = shash_desc_ctx(desc);
+
+	*crcp = *mctx;
+
+	return 0;
+}
+
+static int crc32_update(struct shash_desc *desc, const u8 *data,
+			unsigned int len)
+{
+	u32 *crcp = shash_desc_ctx(desc);
+
+	*crcp = __crc32_le(*crcp, data, len);
+	return 0;
+}
+
+/* No final XOR 0xFFFFFFFF, like crc32_le */
+static int __crc32_finup(u32 *crcp, const u8 *data, unsigned int len,
+			 u8 *out)
+{
+	*(__le32 *)out = cpu_to_le32(__crc32_le(*crcp, data, len));
+	return 0;
+}
+
+static int crc32_finup(struct shash_desc *desc, const u8 *data,
+		       unsigned int len, u8 *out)
+{
+	return __crc32_finup(shash_desc_ctx(desc), data, len, out);
+}
+
+static int crc32_final(struct shash_desc *desc, u8 *out)
+{
+	u32 *crcp = shash_desc_ctx(desc);
+
+	*(__le32 *)out = cpu_to_le32p(crcp);
+	return 0;
+}
+
+static int crc32_digest(struct shash_desc *desc, const u8 *data,
+			unsigned int len, u8 *out)
+{
+	return __crc32_finup(crypto_shash_ctx(desc->tfm), data, len,
+			     out);
+}
+static struct shash_alg alg = {
+	.setkey		= crc32_setkey,
+	.init		= crc32_init,
+	.update		= crc32_update,
+	.final		= crc32_final,
+	.finup		= crc32_finup,
+	.digest		= crc32_digest,
+	.descsize	= sizeof(u32),
+	.digestsize	= CHKSUM_DIGEST_SIZE,
+	.base		= {
+		.cra_name		= "crc32",
+		.cra_driver_name	= "crc32-generic",
+		.cra_priority		= 100,
+		.cra_blocksize		= CHKSUM_BLOCK_SIZE,
+		.cra_ctxsize		= sizeof(u32),
+		.cra_module		= THIS_MODULE,
+		.cra_init		= crc32_cra_init,
+	}
+};
+
+static int __init crc32_mod_init(void)
+{
+	return crypto_register_shash(&alg);
+}
+
+static void __exit crc32_mod_fini(void)
+{
+	crypto_unregister_shash(&alg);
+}
+
+module_init(crc32_mod_init);
+module_exit(crc32_mod_fini);
+
+MODULE_AUTHOR("Alexander Boyko <alexander_boyko@xyratex.com>");
+MODULE_DESCRIPTION("CRC32 calculations wrapper for lib/crc32");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_CRYPTO("crc32");
+MODULE_ALIAS_CRYPTO("crc32-generic");