xref: /openbmc/linux/crypto/md4.c (revision 22246614)
1 /*
2  * Cryptographic API.
3  *
4  * MD4 Message Digest Algorithm (RFC1320).
5  *
6  * Implementation derived from Andrew Tridgell and Steve French's
7  * CIFS MD4 implementation, and the cryptoapi implementation
8  * originally based on the public domain implementation written
9  * by Colin Plumb in 1993.
10  *
11  * Copyright (c) Andrew Tridgell 1997-1998.
12  * Modified by Steve French (sfrench@us.ibm.com) 2002
13  * Copyright (c) Cryptoapi developers.
14  * Copyright (c) 2002 David S. Miller (davem@redhat.com)
15  * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
16  *
17  * This program is free software; you can redistribute it and/or modify
18  * it under the terms of the GNU General Public License as published by
19  * the Free Software Foundation; either version 2 of the License, or
20  * (at your option) any later version.
21  *
22  */
23 #include <linux/init.h>
24 #include <linux/crypto.h>
25 #include <linux/kernel.h>
26 #include <linux/string.h>
27 #include <linux/types.h>
28 #include <asm/byteorder.h>
29 
30 #define MD4_DIGEST_SIZE		16
31 #define MD4_HMAC_BLOCK_SIZE	64
32 #define MD4_BLOCK_WORDS		16
33 #define MD4_HASH_WORDS		4
34 
35 struct md4_ctx {
36 	u32 hash[MD4_HASH_WORDS];
37 	u32 block[MD4_BLOCK_WORDS];
38 	u64 byte_count;
39 };
40 
41 static inline u32 lshift(u32 x, unsigned int s)
42 {
43 	x &= 0xFFFFFFFF;
44 	return ((x << s) & 0xFFFFFFFF) | (x >> (32 - s));
45 }
46 
47 static inline u32 F(u32 x, u32 y, u32 z)
48 {
49 	return (x & y) | ((~x) & z);
50 }
51 
52 static inline u32 G(u32 x, u32 y, u32 z)
53 {
54 	return (x & y) | (x & z) | (y & z);
55 }
56 
57 static inline u32 H(u32 x, u32 y, u32 z)
58 {
59 	return x ^ y ^ z;
60 }
61 
62 #define ROUND1(a,b,c,d,k,s) (a = lshift(a + F(b,c,d) + k, s))
63 #define ROUND2(a,b,c,d,k,s) (a = lshift(a + G(b,c,d) + k + (u32)0x5A827999,s))
64 #define ROUND3(a,b,c,d,k,s) (a = lshift(a + H(b,c,d) + k + (u32)0x6ED9EBA1,s))
65 
66 /* XXX: this stuff can be optimized */
67 static inline void le32_to_cpu_array(u32 *buf, unsigned int words)
68 {
69 	while (words--) {
70 		__le32_to_cpus(buf);
71 		buf++;
72 	}
73 }
74 
75 static inline void cpu_to_le32_array(u32 *buf, unsigned int words)
76 {
77 	while (words--) {
78 		__cpu_to_le32s(buf);
79 		buf++;
80 	}
81 }
82 
83 static void md4_transform(u32 *hash, u32 const *in)
84 {
85 	u32 a, b, c, d;
86 
87 	a = hash[0];
88 	b = hash[1];
89 	c = hash[2];
90 	d = hash[3];
91 
92 	ROUND1(a, b, c, d, in[0], 3);
93 	ROUND1(d, a, b, c, in[1], 7);
94 	ROUND1(c, d, a, b, in[2], 11);
95 	ROUND1(b, c, d, a, in[3], 19);
96 	ROUND1(a, b, c, d, in[4], 3);
97 	ROUND1(d, a, b, c, in[5], 7);
98 	ROUND1(c, d, a, b, in[6], 11);
99 	ROUND1(b, c, d, a, in[7], 19);
100 	ROUND1(a, b, c, d, in[8], 3);
101 	ROUND1(d, a, b, c, in[9], 7);
102 	ROUND1(c, d, a, b, in[10], 11);
103 	ROUND1(b, c, d, a, in[11], 19);
104 	ROUND1(a, b, c, d, in[12], 3);
105 	ROUND1(d, a, b, c, in[13], 7);
106 	ROUND1(c, d, a, b, in[14], 11);
107 	ROUND1(b, c, d, a, in[15], 19);
108 
109 	ROUND2(a, b, c, d,in[ 0], 3);
110 	ROUND2(d, a, b, c, in[4], 5);
111 	ROUND2(c, d, a, b, in[8], 9);
112 	ROUND2(b, c, d, a, in[12], 13);
113 	ROUND2(a, b, c, d, in[1], 3);
114 	ROUND2(d, a, b, c, in[5], 5);
115 	ROUND2(c, d, a, b, in[9], 9);
116 	ROUND2(b, c, d, a, in[13], 13);
117 	ROUND2(a, b, c, d, in[2], 3);
118 	ROUND2(d, a, b, c, in[6], 5);
119 	ROUND2(c, d, a, b, in[10], 9);
120 	ROUND2(b, c, d, a, in[14], 13);
121 	ROUND2(a, b, c, d, in[3], 3);
122 	ROUND2(d, a, b, c, in[7], 5);
123 	ROUND2(c, d, a, b, in[11], 9);
124 	ROUND2(b, c, d, a, in[15], 13);
125 
126 	ROUND3(a, b, c, d,in[ 0], 3);
127 	ROUND3(d, a, b, c, in[8], 9);
128 	ROUND3(c, d, a, b, in[4], 11);
129 	ROUND3(b, c, d, a, in[12], 15);
130 	ROUND3(a, b, c, d, in[2], 3);
131 	ROUND3(d, a, b, c, in[10], 9);
132 	ROUND3(c, d, a, b, in[6], 11);
133 	ROUND3(b, c, d, a, in[14], 15);
134 	ROUND3(a, b, c, d, in[1], 3);
135 	ROUND3(d, a, b, c, in[9], 9);
136 	ROUND3(c, d, a, b, in[5], 11);
137 	ROUND3(b, c, d, a, in[13], 15);
138 	ROUND3(a, b, c, d, in[3], 3);
139 	ROUND3(d, a, b, c, in[11], 9);
140 	ROUND3(c, d, a, b, in[7], 11);
141 	ROUND3(b, c, d, a, in[15], 15);
142 
143 	hash[0] += a;
144 	hash[1] += b;
145 	hash[2] += c;
146 	hash[3] += d;
147 }
148 
149 static inline void md4_transform_helper(struct md4_ctx *ctx)
150 {
151 	le32_to_cpu_array(ctx->block, sizeof(ctx->block) / sizeof(u32));
152 	md4_transform(ctx->hash, ctx->block);
153 }
154 
155 static void md4_init(struct crypto_tfm *tfm)
156 {
157 	struct md4_ctx *mctx = crypto_tfm_ctx(tfm);
158 
159 	mctx->hash[0] = 0x67452301;
160 	mctx->hash[1] = 0xefcdab89;
161 	mctx->hash[2] = 0x98badcfe;
162 	mctx->hash[3] = 0x10325476;
163 	mctx->byte_count = 0;
164 }
165 
166 static void md4_update(struct crypto_tfm *tfm, const u8 *data, unsigned int len)
167 {
168 	struct md4_ctx *mctx = crypto_tfm_ctx(tfm);
169 	const u32 avail = sizeof(mctx->block) - (mctx->byte_count & 0x3f);
170 
171 	mctx->byte_count += len;
172 
173 	if (avail > len) {
174 		memcpy((char *)mctx->block + (sizeof(mctx->block) - avail),
175 		       data, len);
176 		return;
177 	}
178 
179 	memcpy((char *)mctx->block + (sizeof(mctx->block) - avail),
180 	       data, avail);
181 
182 	md4_transform_helper(mctx);
183 	data += avail;
184 	len -= avail;
185 
186 	while (len >= sizeof(mctx->block)) {
187 		memcpy(mctx->block, data, sizeof(mctx->block));
188 		md4_transform_helper(mctx);
189 		data += sizeof(mctx->block);
190 		len -= sizeof(mctx->block);
191 	}
192 
193 	memcpy(mctx->block, data, len);
194 }
195 
196 static void md4_final(struct crypto_tfm *tfm, u8 *out)
197 {
198 	struct md4_ctx *mctx = crypto_tfm_ctx(tfm);
199 	const unsigned int offset = mctx->byte_count & 0x3f;
200 	char *p = (char *)mctx->block + offset;
201 	int padding = 56 - (offset + 1);
202 
203 	*p++ = 0x80;
204 	if (padding < 0) {
205 		memset(p, 0x00, padding + sizeof (u64));
206 		md4_transform_helper(mctx);
207 		p = (char *)mctx->block;
208 		padding = 56;
209 	}
210 
211 	memset(p, 0, padding);
212 	mctx->block[14] = mctx->byte_count << 3;
213 	mctx->block[15] = mctx->byte_count >> 29;
214 	le32_to_cpu_array(mctx->block, (sizeof(mctx->block) -
215 	                  sizeof(u64)) / sizeof(u32));
216 	md4_transform(mctx->hash, mctx->block);
217 	cpu_to_le32_array(mctx->hash, sizeof(mctx->hash) / sizeof(u32));
218 	memcpy(out, mctx->hash, sizeof(mctx->hash));
219 	memset(mctx, 0, sizeof(*mctx));
220 }
221 
222 static struct crypto_alg alg = {
223 	.cra_name	=	"md4",
224 	.cra_flags	=	CRYPTO_ALG_TYPE_DIGEST,
225 	.cra_blocksize	=	MD4_HMAC_BLOCK_SIZE,
226 	.cra_ctxsize	=	sizeof(struct md4_ctx),
227 	.cra_module	=	THIS_MODULE,
228 	.cra_list       =       LIST_HEAD_INIT(alg.cra_list),
229 	.cra_u		=	{ .digest = {
230 	.dia_digestsize	=	MD4_DIGEST_SIZE,
231 	.dia_init   	= 	md4_init,
232 	.dia_update 	=	md4_update,
233 	.dia_final  	=	md4_final } }
234 };
235 
236 static int __init md4_mod_init(void)
237 {
238 	return crypto_register_alg(&alg);
239 }
240 
241 static void __exit md4_mod_fini(void)
242 {
243 	crypto_unregister_alg(&alg);
244 }
245 
246 module_init(md4_mod_init);
247 module_exit(md4_mod_fini);
248 
249 MODULE_LICENSE("GPL");
250 MODULE_DESCRIPTION("MD4 Message Digest Algorithm");
251 
252