crypto/md5.c - linux - Git at Google

 /*
  * Cryptographic API.
  *
  * MD5 Message Digest Algorithm (RFC1321).
  *
  * Derived from cryptoapi implementation, originally based on the
  * public domain implementation written by Colin Plumb in 1993.
  *
  * Copyright (c) Cryptoapi developers.
  * 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 <crypto/internal/hash.h>
 #include <crypto/md5.h>
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/string.h>
 #include <linux/types.h>
 #include <asm/byteorder.h>

 #define MD5_DIGEST_WORDS 4
 #define MD5_MESSAGE_BYTES 64

 const u8 md5_zero_message_hash[MD5_DIGEST_SIZE] = {
 	0xd4, 0x1d, 0x8c, 0xd9, 0x8f, 0x00, 0xb2, 0x04,
 	0xe9, 0x80, 0x09, 0x98, 0xec, 0xf8, 0x42, 0x7e,
 };
 EXPORT_SYMBOL_GPL(md5_zero_message_hash);

 #define F1(x, y, z)	(z ^ (x & (y ^ z)))
 #define F2(x, y, z)	F1(z, x, y)
 #define F3(x, y, z)	(x ^ y ^ z)
 #define F4(x, y, z)	(y ^ (x | ~z))

 #define MD5STEP(f, w, x, y, z, in, s) \
 	(w += f(x, y, z) + in, w = (w<<s | w>>(32-s)) + x)

 static void md5_transform(__u32 *hash, __u32 const *in)
 {
 	u32 a, b, c, d;

 	a = hash[0];
 	b = hash[1];
 	c = hash[2];
 	d = hash[3];

 	MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
 	MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
 	MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
 	MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
 	MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
 	MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
 	MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
 	MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
 	MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
 	MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
 	MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
 	MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
 	MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
 	MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
 	MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
 	MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);

 	MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
 	MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
 	MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
 	MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
 	MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
 	MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
 	MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
 	MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
 	MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
 	MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
 	MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
 	MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
 	MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
 	MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
 	MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
 	MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);

 	MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
 	MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
 	MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
 	MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
 	MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
 	MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
 	MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
 	MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
 	MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
 	MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
 	MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
 	MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
 	MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
 	MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
 	MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
 	MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);

 	MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
 	MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
 	MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
 	MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
 	MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
 	MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
 	MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
 	MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
 	MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
 	MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
 	MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
 	MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
 	MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
 	MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
 	MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
 	MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);

 	hash[0] += a;
 	hash[1] += b;
 	hash[2] += c;
 	hash[3] += d;
 }

 static inline void md5_transform_helper(struct md5_state *ctx)
 {
 	le32_to_cpu_array(ctx->block, sizeof(ctx->block) / sizeof(u32));
 	md5_transform(ctx->hash, ctx->block);
 }

 static int md5_init(struct shash_desc *desc)
 {
 	struct md5_state *mctx = shash_desc_ctx(desc);

 	mctx->hash[0] = MD5_H0;
 	mctx->hash[1] = MD5_H1;
 	mctx->hash[2] = MD5_H2;
 	mctx->hash[3] = MD5_H3;
 	mctx->byte_count = 0;

 	return 0;
 }

 static int md5_update(struct shash_desc *desc, const u8 *data, unsigned int len)
 {
 	struct md5_state *mctx = shash_desc_ctx(desc);
 	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 0;
 	}

 	memcpy((char *)mctx->block + (sizeof(mctx->block) - avail),
 	       data, avail);

 	md5_transform_helper(mctx);
 	data += avail;
 	len -= avail;

 	while (len >= sizeof(mctx->block)) {
 		memcpy(mctx->block, data, sizeof(mctx->block));
 		md5_transform_helper(mctx);
 		data += sizeof(mctx->block);
 		len -= sizeof(mctx->block);
 	}

 	memcpy(mctx->block, data, len);

 	return 0;
 }

 static int md5_final(struct shash_desc *desc, u8 *out)
 {
 	struct md5_state *mctx = shash_desc_ctx(desc);
 	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));
 		md5_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));
 	md5_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));

 	return 0;
 }

 static int md5_export(struct shash_desc *desc, void *out)
 {
 	struct md5_state *ctx = shash_desc_ctx(desc);

 	memcpy(out, ctx, sizeof(*ctx));
 	return 0;
 }

 static int md5_import(struct shash_desc *desc, const void *in)
 {
 	struct md5_state *ctx = shash_desc_ctx(desc);

 	memcpy(ctx, in, sizeof(*ctx));
 	return 0;
 }

 static struct shash_alg alg = {
 	.digestsize	=	MD5_DIGEST_SIZE,
 	.init		=	md5_init,
 	.update		=	md5_update,
 	.final		=	md5_final,
 	.export		=	md5_export,
 	.import		=	md5_import,
 	.descsize	=	sizeof(struct md5_state),
 	.statesize	=	sizeof(struct md5_state),
 	.base		=	{
 		.cra_name	=	"md5",
 		.cra_blocksize	=	MD5_HMAC_BLOCK_SIZE,
 		.cra_module	=	THIS_MODULE,
 	}
 };

 static int __init md5_mod_init(void)
 {
 	return crypto_register_shash(&alg);
 }

 static void __exit md5_mod_fini(void)
 {
 	crypto_unregister_shash(&alg);
 }

 subsys_initcall(md5_mod_init);
 module_exit(md5_mod_fini);

 MODULE_LICENSE("GPL");
 MODULE_DESCRIPTION("MD5 Message Digest Algorithm");
 MODULE_ALIAS_CRYPTO("md5");
	/*
	* Cryptographic API.
	*
	* MD5 Message Digest Algorithm (RFC1321).
	*
	* Derived from cryptoapi implementation, originally based on the
	* public domain implementation written by Colin Plumb in 1993.
	*
	* Copyright (c) Cryptoapi developers.
	* 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 <crypto/internal/hash.h>
	#include <crypto/md5.h>
	#include <linux/init.h>
	#include <linux/module.h>
	#include <linux/string.h>
	#include <linux/types.h>
	#include <asm/byteorder.h>

	#define MD5_DIGEST_WORDS 4
	#define MD5_MESSAGE_BYTES 64

	const u8 md5_zero_message_hash[MD5_DIGEST_SIZE] = {
	0xd4, 0x1d, 0x8c, 0xd9, 0x8f, 0x00, 0xb2, 0x04,
	0xe9, 0x80, 0x09, 0x98, 0xec, 0xf8, 0x42, 0x7e,
	};
	EXPORT_SYMBOL_GPL(md5_zero_message_hash);

	#define F1(x, y, z) (z ^ (x & (y ^ z)))
	#define F2(x, y, z) F1(z, x, y)
	#define F3(x, y, z) (x ^ y ^ z)
	#define F4(x, y, z) (y ^ (x \| ~z))

	#define MD5STEP(f, w, x, y, z, in, s) \
	(w += f(x, y, z) + in, w = (w<<s \| w>>(32-s)) + x)

	static void md5_transform(__u32 hash, __u32 const in)
	{
	u32 a, b, c, d;

	a = hash[0];
	b = hash[1];
	c = hash[2];
	d = hash[3];

	MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
	MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
	MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
	MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
	MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
	MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
	MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
	MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
	MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
	MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
	MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
	MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
	MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
	MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
	MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
	MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);

	MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
	MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
	MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
	MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
	MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
	MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
	MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
	MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
	MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
	MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
	MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
	MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
	MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
	MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
	MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
	MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);

	MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
	MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
	MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
	MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
	MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
	MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
	MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
	MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
	MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
	MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
	MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
	MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
	MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
	MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
	MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
	MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);

	MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
	MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
	MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
	MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
	MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
	MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
	MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
	MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
	MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
	MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
	MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
	MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
	MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
	MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
	MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
	MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);

	hash[0] += a;
	hash[1] += b;
	hash[2] += c;
	hash[3] += d;
	}

	static inline void md5_transform_helper(struct md5_state *ctx)
	{
	le32_to_cpu_array(ctx->block, sizeof(ctx->block) / sizeof(u32));
	md5_transform(ctx->hash, ctx->block);
	}

	static int md5_init(struct shash_desc *desc)
	{
	struct md5_state *mctx = shash_desc_ctx(desc);

	mctx->hash[0] = MD5_H0;
	mctx->hash[1] = MD5_H1;
	mctx->hash[2] = MD5_H2;
	mctx->hash[3] = MD5_H3;
	mctx->byte_count = 0;

	return 0;
	}

	static int md5_update(struct shash_desc desc, const u8 data, unsigned int len)
	{
	struct md5_state *mctx = shash_desc_ctx(desc);
	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 0;
	}

	memcpy((char *)mctx->block + (sizeof(mctx->block) - avail),
	data, avail);

	md5_transform_helper(mctx);
	data += avail;
	len -= avail;

	while (len >= sizeof(mctx->block)) {
	memcpy(mctx->block, data, sizeof(mctx->block));
	md5_transform_helper(mctx);
	data += sizeof(mctx->block);
	len -= sizeof(mctx->block);
	}

	memcpy(mctx->block, data, len);

	return 0;
	}

	static int md5_final(struct shash_desc desc, u8 out)
	{
	struct md5_state *mctx = shash_desc_ctx(desc);
	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));
	md5_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));
	md5_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));

	return 0;
	}

	static int md5_export(struct shash_desc desc, void out)
	{
	struct md5_state *ctx = shash_desc_ctx(desc);

	memcpy(out, ctx, sizeof(*ctx));
	return 0;
	}

	static int md5_import(struct shash_desc desc, const void in)
	{
	struct md5_state *ctx = shash_desc_ctx(desc);

	memcpy(ctx, in, sizeof(*ctx));
	return 0;
	}

	static struct shash_alg alg = {
	.digestsize = MD5_DIGEST_SIZE,
	.init = md5_init,
	.update = md5_update,
	.final = md5_final,
	.export = md5_export,
	.import = md5_import,
	.descsize = sizeof(struct md5_state),
	.statesize = sizeof(struct md5_state),
	.base = {
	.cra_name = "md5",
	.cra_blocksize = MD5_HMAC_BLOCK_SIZE,
	.cra_module = THIS_MODULE,
	}
	};

	static int __init md5_mod_init(void)
	{
	return crypto_register_shash(&alg);
	}

	static void __exit md5_mod_fini(void)
	{
	crypto_unregister_shash(&alg);
	}

	subsys_initcall(md5_mod_init);
	module_exit(md5_mod_fini);

	MODULE_LICENSE("GPL");
	MODULE_DESCRIPTION("MD5 Message Digest Algorithm");
	MODULE_ALIAS_CRYPTO("md5");