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18#include <crypto/internal/hash.h>
19#include <linux/init.h>
20#include <linux/module.h>
21#include <linux/string.h>
22#include <linux/types.h>
23#include <asm/byteorder.h>
24
25#define MD5_DIGEST_SIZE 16
26#define MD5_HMAC_BLOCK_SIZE 64
27#define MD5_BLOCK_WORDS 16
28#define MD5_HASH_WORDS 4
29
30#define F1(x, y, z) (z ^ (x & (y ^ z)))
31#define F2(x, y, z) F1(z, x, y)
32#define F3(x, y, z) (x ^ y ^ z)
33#define F4(x, y, z) (y ^ (x | ~z))
34
35#define MD5STEP(f, w, x, y, z, in, s) \
36 (w += f(x, y, z) + in, w = (w<<s | w>>(32-s)) + x)
37
38struct md5_ctx {
39 u32 hash[MD5_HASH_WORDS];
40 u32 block[MD5_BLOCK_WORDS];
41 u64 byte_count;
42};
43
44static void md5_transform(u32 *hash, u32 const *in)
45{
46 u32 a, b, c, d;
47
48 a = hash[0];
49 b = hash[1];
50 c = hash[2];
51 d = hash[3];
52
53 MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
54 MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
55 MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
56 MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
57 MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
58 MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
59 MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
60 MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
61 MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
62 MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
63 MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
64 MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
65 MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
66 MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
67 MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
68 MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
69
70 MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
71 MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
72 MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
73 MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
74 MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
75 MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
76 MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
77 MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
78 MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
79 MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
80 MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
81 MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
82 MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
83 MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
84 MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
85 MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
86
87 MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
88 MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
89 MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
90 MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
91 MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
92 MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
93 MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
94 MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
95 MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
96 MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
97 MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
98 MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
99 MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
100 MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
101 MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
102 MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
103
104 MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
105 MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
106 MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
107 MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
108 MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
109 MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
110 MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
111 MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
112 MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
113 MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
114 MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
115 MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
116 MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
117 MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
118 MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
119 MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);
120
121 hash[0] += a;
122 hash[1] += b;
123 hash[2] += c;
124 hash[3] += d;
125}
126
127
128static inline void le32_to_cpu_array(u32 *buf, unsigned int words)
129{
130 while (words--) {
131 __le32_to_cpus(buf);
132 buf++;
133 }
134}
135
136static inline void cpu_to_le32_array(u32 *buf, unsigned int words)
137{
138 while (words--) {
139 __cpu_to_le32s(buf);
140 buf++;
141 }
142}
143
144static inline void md5_transform_helper(struct md5_ctx *ctx)
145{
146 le32_to_cpu_array(ctx->block, sizeof(ctx->block) / sizeof(u32));
147 md5_transform(ctx->hash, ctx->block);
148}
149
150static int md5_init(struct shash_desc *desc)
151{
152 struct md5_ctx *mctx = shash_desc_ctx(desc);
153
154 mctx->hash[0] = 0x67452301;
155 mctx->hash[1] = 0xefcdab89;
156 mctx->hash[2] = 0x98badcfe;
157 mctx->hash[3] = 0x10325476;
158 mctx->byte_count = 0;
159
160 return 0;
161}
162
163static int md5_update(struct shash_desc *desc, const u8 *data, unsigned int len)
164{
165 struct md5_ctx *mctx = shash_desc_ctx(desc);
166 const u32 avail = sizeof(mctx->block) - (mctx->byte_count & 0x3f);
167
168 mctx->byte_count += len;
169
170 if (avail > len) {
171 memcpy((char *)mctx->block + (sizeof(mctx->block) - avail),
172 data, len);
173 return 0;
174 }
175
176 memcpy((char *)mctx->block + (sizeof(mctx->block) - avail),
177 data, avail);
178
179 md5_transform_helper(mctx);
180 data += avail;
181 len -= avail;
182
183 while (len >= sizeof(mctx->block)) {
184 memcpy(mctx->block, data, sizeof(mctx->block));
185 md5_transform_helper(mctx);
186 data += sizeof(mctx->block);
187 len -= sizeof(mctx->block);
188 }
189
190 memcpy(mctx->block, data, len);
191
192 return 0;
193}
194
195static int md5_final(struct shash_desc *desc, u8 *out)
196{
197 struct md5_ctx *mctx = shash_desc_ctx(desc);
198 const unsigned int offset = mctx->byte_count & 0x3f;
199 char *p = (char *)mctx->block + offset;
200 int padding = 56 - (offset + 1);
201
202 *p++ = 0x80;
203 if (padding < 0) {
204 memset(p, 0x00, padding + sizeof (u64));
205 md5_transform_helper(mctx);
206 p = (char *)mctx->block;
207 padding = 56;
208 }
209
210 memset(p, 0, padding);
211 mctx->block[14] = mctx->byte_count << 3;
212 mctx->block[15] = mctx->byte_count >> 29;
213 le32_to_cpu_array(mctx->block, (sizeof(mctx->block) -
214 sizeof(u64)) / sizeof(u32));
215 md5_transform(mctx->hash, mctx->block);
216 cpu_to_le32_array(mctx->hash, sizeof(mctx->hash) / sizeof(u32));
217 memcpy(out, mctx->hash, sizeof(mctx->hash));
218 memset(mctx, 0, sizeof(*mctx));
219
220 return 0;
221}
222
223static struct shash_alg alg = {
224 .digestsize = MD5_DIGEST_SIZE,
225 .init = md5_init,
226 .update = md5_update,
227 .final = md5_final,
228 .descsize = sizeof(struct md5_ctx),
229 .base = {
230 .cra_name = "md5",
231 .cra_flags = CRYPTO_ALG_TYPE_SHASH,
232 .cra_blocksize = MD5_HMAC_BLOCK_SIZE,
233 .cra_module = THIS_MODULE,
234 }
235};
236
237static int __init md5_mod_init(void)
238{
239 return crypto_register_shash(&alg);
240}
241
242static void __exit md5_mod_fini(void)
243{
244 crypto_unregister_shash(&alg);
245}
246
247module_init(md5_mod_init);
248module_exit(md5_mod_fini);
249
250MODULE_LICENSE("GPL");
251MODULE_DESCRIPTION("MD5 Message Digest Algorithm");
252
