[CRYPTO]: Forgot to add crypto_null.c in previous commit.

crypto/crypto_null.c

+/* 
+ * Cryptographic API.
+ *
+ * Null algorithms, aka Much Ado About Nothing.
+ *
+ * These are needed for IPsec, and may be useful in general for
+ * testing & debugging.
+ * 
+ * The null cipher is compliant with RFC2410.
+ *
+ * Copyright (c) 2002 James Morris <jmorris@intercode.com.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 <linux/init.h>
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <asm/scatterlist.h>
+#include <linux/crypto.h>
+
+#define NULL_KEY_SIZE		0
+#define NULL_BLOCK_SIZE		1
+#define NULL_DIGEST_SIZE	0
+
+static void null_compress(void)
+{ }
+
+static void null_decompress(void)
+{ }
+
+static void null_init(void *ctx)
+{ }
+
+static void null_update(void *ctx, const u8 *data, unsigned int len)
+{ }
+
+static void null_final(void *ctx, u8 *out)
+{ }
+
+static int null_setkey(void *ctx, const u8 *key,
+                       unsigned int keylen, u32 *flags)
+{ return 0; }
+
+static void null_encrypt(void *ctx, u8 *dst, const u8 *src)
+{ }
+
+static void null_decrypt(void *ctx, u8 *dst, const u8 *src)
+{ }
+
+static struct crypto_alg compress_null = {
+	.cra_name		=	"compress_null",
+	.cra_flags		=	CRYPTO_ALG_TYPE_COMPRESS,
+	.cra_blocksize		=	NULL_BLOCK_SIZE,
+	.cra_ctxsize		=	0,
+	.cra_module		=	THIS_MODULE,
+	.cra_list		=       LIST_HEAD_INIT(compress_null.cra_list),
+	.cra_u			=	{ .compress = {
+	.coa_compress 		=	null_compress,
+	.coa_decompress		=	null_decompress } }
+};
+
+static struct crypto_alg digest_null = {
+	.cra_name		=	"digest_null",
+	.cra_flags		=	CRYPTO_ALG_TYPE_DIGEST,
+	.cra_blocksize		=	NULL_BLOCK_SIZE,
+	.cra_ctxsize		=	0,
+	.cra_module		=	THIS_MODULE,
+	.cra_list		=       LIST_HEAD_INIT(digest_null.cra_list),	
+	.cra_u			=	{ .digest = {
+	.dia_digestsize		=	NULL_DIGEST_SIZE,
+	.dia_init   		=	null_init,
+	.dia_update 		=	null_update,
+	.dia_final  		=	null_final } }
+};
+
+static struct crypto_alg cipher_null = {
+	.cra_name		=	"cipher_null",
+	.cra_flags		=	CRYPTO_ALG_TYPE_CIPHER,
+	.cra_blocksize		=	NULL_BLOCK_SIZE,
+	.cra_ctxsize		=	0,
+	.cra_module		=	THIS_MODULE,
+	.cra_list		=	LIST_HEAD_INIT(cipher_null.cra_list),
+	.cra_u			=	{ .cipher = {
+	.cia_min_keysize	=	NULL_KEY_SIZE,
+	.cia_max_keysize	=	NULL_KEY_SIZE,
+	.cia_ivsize		=	0,
+	.cia_setkey		= 	null_setkey,
+	.cia_encrypt		=	null_encrypt,
+	.cia_decrypt		=	null_decrypt } }
+};
+
+static int __init init(void)
+{
+	int ret = 0;
+	
+	ret = crypto_register_alg(&cipher_null);
+	if (ret < 0)
+		goto out;
+
+	ret = crypto_register_alg(&digest_null);
+	if (ret < 0) {
+		crypto_unregister_alg(&cipher_null);
+		goto out;
+	}
+
+	ret = crypto_register_alg(&compress_null);
+	if (ret < 0) {
+		crypto_unregister_alg(&digest_null);
+		crypto_unregister_alg(&cipher_null);
+		goto out;
+	}
+
+out:	
+	return ret;
+}
+
+static void __exit fini(void)
+{
+	crypto_unregister_alg(&compress_null);
+	crypto_unregister_alg(&digest_null);
+	crypto_unregister_alg(&cipher_null);
+}
+
+module_init(init);
+module_exit(fini);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Null Cryptographic Algorithms");