4 * MD5 Message Digest Algorithm (RFC1321).
6 * Derived from cryptoapi implementation, originally based on the
7 * public domain implementation written by Colin Plumb in 1993.
9 * Copyright (c) Cryptoapi developers.
10 * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
12 * This program is free software; you can redistribute it and/or modify it
13 * under the terms of the GNU General Public License as published by the Free
14 * Software Foundation; either version 2 of the License, or (at your option)
18 #include <crypto/internal/hash.h>
19 #include <crypto/md5.h>
20 #include <linux/init.h>
21 #include <linux/module.h>
22 #include <linux/string.h>
23 #include <linux/types.h>
24 #include <linux/cryptohash.h>
25 #include <asm/byteorder.h>
27 const u8 md5_zero_message_hash[MD5_DIGEST_SIZE] = {
28 0xd4, 0x1d, 0x8c, 0xd9, 0x8f, 0x00, 0xb2, 0x04,
29 0xe9, 0x80, 0x09, 0x98, 0xec, 0xf8, 0x42, 0x7e,
31 EXPORT_SYMBOL_GPL(md5_zero_message_hash);
33 static inline void md5_transform_helper(struct md5_state *ctx)
35 le32_to_cpu_array(ctx->block, sizeof(ctx->block) / sizeof(u32));
36 md5_transform(ctx->hash, ctx->block);
39 static int md5_init(struct shash_desc *desc)
41 struct md5_state *mctx = shash_desc_ctx(desc);
43 mctx->hash[0] = MD5_H0;
44 mctx->hash[1] = MD5_H1;
45 mctx->hash[2] = MD5_H2;
46 mctx->hash[3] = MD5_H3;
52 static int md5_update(struct shash_desc *desc, const u8 *data, unsigned int len)
54 struct md5_state *mctx = shash_desc_ctx(desc);
55 const u32 avail = sizeof(mctx->block) - (mctx->byte_count & 0x3f);
57 mctx->byte_count += len;
60 memcpy((char *)mctx->block + (sizeof(mctx->block) - avail),
65 memcpy((char *)mctx->block + (sizeof(mctx->block) - avail),
68 md5_transform_helper(mctx);
72 while (len >= sizeof(mctx->block)) {
73 memcpy(mctx->block, data, sizeof(mctx->block));
74 md5_transform_helper(mctx);
75 data += sizeof(mctx->block);
76 len -= sizeof(mctx->block);
79 memcpy(mctx->block, data, len);
84 static int md5_final(struct shash_desc *desc, u8 *out)
86 struct md5_state *mctx = shash_desc_ctx(desc);
87 const unsigned int offset = mctx->byte_count & 0x3f;
88 char *p = (char *)mctx->block + offset;
89 int padding = 56 - (offset + 1);
93 memset(p, 0x00, padding + sizeof (u64));
94 md5_transform_helper(mctx);
95 p = (char *)mctx->block;
99 memset(p, 0, padding);
100 mctx->block[14] = mctx->byte_count << 3;
101 mctx->block[15] = mctx->byte_count >> 29;
102 le32_to_cpu_array(mctx->block, (sizeof(mctx->block) -
103 sizeof(u64)) / sizeof(u32));
104 md5_transform(mctx->hash, mctx->block);
105 cpu_to_le32_array(mctx->hash, sizeof(mctx->hash) / sizeof(u32));
106 memcpy(out, mctx->hash, sizeof(mctx->hash));
107 memset(mctx, 0, sizeof(*mctx));
112 static int md5_export(struct shash_desc *desc, void *out)
114 struct md5_state *ctx = shash_desc_ctx(desc);
116 memcpy(out, ctx, sizeof(*ctx));
120 static int md5_import(struct shash_desc *desc, const void *in)
122 struct md5_state *ctx = shash_desc_ctx(desc);
124 memcpy(ctx, in, sizeof(*ctx));
128 static struct shash_alg alg = {
129 .digestsize = MD5_DIGEST_SIZE,
131 .update = md5_update,
133 .export = md5_export,
134 .import = md5_import,
135 .descsize = sizeof(struct md5_state),
136 .statesize = sizeof(struct md5_state),
139 .cra_flags = CRYPTO_ALG_TYPE_SHASH,
140 .cra_blocksize = MD5_HMAC_BLOCK_SIZE,
141 .cra_module = THIS_MODULE,
145 static int __init md5_mod_init(void)
147 return crypto_register_shash(&alg);
150 static void __exit md5_mod_fini(void)
152 crypto_unregister_shash(&alg);
155 module_init(md5_mod_init);
156 module_exit(md5_mod_fini);
158 MODULE_LICENSE("GPL");
159 MODULE_DESCRIPTION("MD5 Message Digest Algorithm");
160 MODULE_ALIAS_CRYPTO("md5");