patch-2.4.22 linux-2.4.22/crypto/md4.c

• Lines: 251
• Date: 2003-08-25 04:44:40.000000000 -0700
• Orig file: linux-2.4.21/crypto/md4.c
• Orig date: 1969-12-31 16:00:00.000000000 -0800

diff -urN linux-2.4.21/crypto/md4.c linux-2.4.22/crypto/md4.c
@@ -0,0 +1,250 @@
+/* 
+ * Cryptographic API.
+ *
+ * MD4 Message Digest Algorithm (RFC1320).
+ *
+ * Implementation derived from Andrew Tridgell and Steve French's
+ * CIFS MD4 implementation, and the cryptoapi implementation
+ * originally based on the public domain implementation written
+ * by Colin Plumb in 1993.
+ *
+ * Copyright (c) Andrew Tridgell 1997-1998.
+ * Modified by Steve French (sfrench@us.ibm.com) 2002
+ * Copyright (c) Cryptoapi developers.
+ * Copyright (c) 2002 David S. Miller (davem@redhat.com)
+ * 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/crypto.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <asm/byteorder.h>
+
+#define MD4_DIGEST_SIZE		16
+#define MD4_HMAC_BLOCK_SIZE	64
+#define MD4_BLOCK_WORDS		16
+#define MD4_HASH_WORDS		4
+
+struct md4_ctx {
+	u32 hash[MD4_HASH_WORDS];
+	u32 block[MD4_BLOCK_WORDS];
+	u64 byte_count;
+};
+
+static inline u32 lshift(u32 x, unsigned int s)
+{
+	x &= 0xFFFFFFFF;
+	return ((x << s) & 0xFFFFFFFF) | (x >> (32 - s));
+}
+
+static inline u32 F(u32 x, u32 y, u32 z)
+{
+	return (x & y) | ((~x) & z);
+}
+
+static inline u32 G(u32 x, u32 y, u32 z)
+{
+	return (x & y) | (x & z) | (y & z);
+}
+
+static inline u32 H(u32 x, u32 y, u32 z)
+{
+	return x ^ y ^ z;
+}
+                        
+#define ROUND1(a,b,c,d,k,s) (a = lshift(a + F(b,c,d) + k, s))
+#define ROUND2(a,b,c,d,k,s) (a = lshift(a + G(b,c,d) + k + (u32)0x5A827999,s))
+#define ROUND3(a,b,c,d,k,s) (a = lshift(a + H(b,c,d) + k + (u32)0x6ED9EBA1,s))
+
+/* XXX: this stuff can be optimized */
+static inline void le32_to_cpu_array(u32 *buf, unsigned int words)
+{
+	while (words--) {
+		__le32_to_cpus(buf);
+		buf++;
+	}
+}
+
+static inline void cpu_to_le32_array(u32 *buf, unsigned int words)
+{
+	while (words--) {
+		__cpu_to_le32s(buf);
+		buf++;
+	}
+}
+
+static void md4_transform(u32 *hash, u32 const *in)
+{
+	u32 a, b, c, d;
+
+	a = hash[0];
+	b = hash[1];
+	c = hash[2];
+	d = hash[3];
+
+	ROUND1(a, b, c, d, in[0], 3);
+	ROUND1(d, a, b, c, in[1], 7);
+	ROUND1(c, d, a, b, in[2], 11);
+	ROUND1(b, c, d, a, in[3], 19);
+	ROUND1(a, b, c, d, in[4], 3);
+	ROUND1(d, a, b, c, in[5], 7);
+	ROUND1(c, d, a, b, in[6], 11);
+	ROUND1(b, c, d, a, in[7], 19);
+	ROUND1(a, b, c, d, in[8], 3);
+	ROUND1(d, a, b, c, in[9], 7);
+	ROUND1(c, d, a, b, in[10], 11);
+	ROUND1(b, c, d, a, in[11], 19);
+	ROUND1(a, b, c, d, in[12], 3);
+	ROUND1(d, a, b, c, in[13], 7);
+	ROUND1(c, d, a, b, in[14], 11);
+	ROUND1(b, c, d, a, in[15], 19);
+
+	ROUND2(a, b, c, d,in[ 0], 3);
+	ROUND2(d, a, b, c, in[4], 5);
+	ROUND2(c, d, a, b, in[8], 9);
+	ROUND2(b, c, d, a, in[12], 13);
+	ROUND2(a, b, c, d, in[1], 3);
+	ROUND2(d, a, b, c, in[5], 5);
+	ROUND2(c, d, a, b, in[9], 9);
+	ROUND2(b, c, d, a, in[13], 13);
+	ROUND2(a, b, c, d, in[2], 3);
+	ROUND2(d, a, b, c, in[6], 5);
+	ROUND2(c, d, a, b, in[10], 9);
+	ROUND2(b, c, d, a, in[14], 13);
+	ROUND2(a, b, c, d, in[3], 3);
+	ROUND2(d, a, b, c, in[7], 5);
+	ROUND2(c, d, a, b, in[11], 9);
+	ROUND2(b, c, d, a, in[15], 13);
+
+	ROUND3(a, b, c, d,in[ 0], 3);
+	ROUND3(d, a, b, c, in[8], 9);
+	ROUND3(c, d, a, b, in[4], 11);
+	ROUND3(b, c, d, a, in[12], 15);
+	ROUND3(a, b, c, d, in[2], 3);
+	ROUND3(d, a, b, c, in[10], 9);
+	ROUND3(c, d, a, b, in[6], 11);
+	ROUND3(b, c, d, a, in[14], 15);
+	ROUND3(a, b, c, d, in[1], 3);
+	ROUND3(d, a, b, c, in[9], 9);
+	ROUND3(c, d, a, b, in[5], 11);
+	ROUND3(b, c, d, a, in[13], 15);
+	ROUND3(a, b, c, d, in[3], 3);
+	ROUND3(d, a, b, c, in[11], 9);
+	ROUND3(c, d, a, b, in[7], 11);
+	ROUND3(b, c, d, a, in[15], 15);
+
+	hash[0] += a;
+	hash[1] += b;
+	hash[2] += c;
+	hash[3] += d;
+}
+
+static inline void md4_transform_helper(struct md4_ctx *ctx)
+{
+	le32_to_cpu_array(ctx->block, sizeof(ctx->block) / sizeof(u32));
+	md4_transform(ctx->hash, ctx->block);
+}
+
+static void md4_init(void *ctx)
+{
+	struct md4_ctx *mctx = ctx;
+
+	mctx->hash[0] = 0x67452301;
+	mctx->hash[1] = 0xefcdab89;
+	mctx->hash[2] = 0x98badcfe;
+	mctx->hash[3] = 0x10325476;
+	mctx->byte_count = 0;
+}
+
+static void md4_update(void *ctx, const u8 *data, unsigned int len)
+{
+	struct md4_ctx *mctx = ctx;
+	const u32 avail = sizeof(mctx->block) - (mctx->byte_count & 0x3f);
+
+	mctx->byte_count += len;
+
+	if (avail > len) {
+		memcpy((char *)mctx->block + (sizeof(mctx->block) - avail),
+		       data, len);
+		return;
+	}
+
+	memcpy((char *)mctx->block + (sizeof(mctx->block) - avail),
+	       data, avail);
+
+	md4_transform_helper(mctx);
+	data += avail;
+	len -= avail;
+
+	while (len >= sizeof(mctx->block)) {
+		memcpy(mctx->block, data, sizeof(mctx->block));
+		md4_transform_helper(mctx);
+		data += sizeof(mctx->block);
+		len -= sizeof(mctx->block);
+	}
+
+	memcpy(mctx->block, data, len);
+}
+
+static void md4_final(void *ctx, u8 *out)
+{
+	struct md4_ctx *mctx = ctx;
+	const unsigned int offset = mctx->byte_count & 0x3f;
+	char *p = (char *)mctx->block + offset;
+	int padding = 56 - (offset + 1);
+
+	*p++ = 0x80;
+	if (padding < 0) {
+		memset(p, 0x00, padding + sizeof (u64));
+		md4_transform_helper(mctx);
+		p = (char *)mctx->block;
+		padding = 56;
+	}
+
+	memset(p, 0, padding);
+	mctx->block[14] = mctx->byte_count << 3;
+	mctx->block[15] = mctx->byte_count >> 29;
+	le32_to_cpu_array(mctx->block, (sizeof(mctx->block) -
+	                  sizeof(u64)) / sizeof(u32));
+	md4_transform(mctx->hash, mctx->block);
+	cpu_to_le32_array(mctx->hash, sizeof(mctx->hash) / sizeof(u32));
+	memcpy(out, mctx->hash, sizeof(mctx->hash));
+	memset(mctx, 0, sizeof(*mctx));
+}
+
+static struct crypto_alg alg = {
+	.cra_name	=	"md4",
+	.cra_flags	=	CRYPTO_ALG_TYPE_DIGEST,
+	.cra_blocksize	=	MD4_HMAC_BLOCK_SIZE,
+	.cra_ctxsize	=	sizeof(struct md4_ctx),
+	.cra_module	=	THIS_MODULE,
+	.cra_list       =       LIST_HEAD_INIT(alg.cra_list),	
+	.cra_u		=	{ .digest = {
+	.dia_digestsize	=	MD4_DIGEST_SIZE,
+	.dia_init   	= 	md4_init,
+	.dia_update 	=	md4_update,
+	.dia_final  	=	md4_final } }
+};
+
+static int __init init(void)
+{
+	return crypto_register_alg(&alg);
+}
+
+static void __exit fini(void)
+{
+	crypto_unregister_alg(&alg);
+}
+
+module_init(init);
+module_exit(fini);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("MD4 Message Digest Algorithm");
+