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23#include <crypto/internal/hash.h>
24#include <linux/init.h>
25#include <linux/kernel.h>
26#include <linux/module.h>
27#include <linux/string.h>
28#include <linux/types.h>
29#include <asm/byteorder.h>
30
31#define MD4_DIGEST_SIZE 16
32#define MD4_HMAC_BLOCK_SIZE 64
33#define MD4_BLOCK_WORDS 16
34#define MD4_HASH_WORDS 4
35
36struct md4_ctx {
37 u32 hash[MD4_HASH_WORDS];
38 u32 block[MD4_BLOCK_WORDS];
39 u64 byte_count;
40};
41
42static inline u32 lshift(u32 x, unsigned int s)
43{
44 x &= 0xFFFFFFFF;
45 return ((x << s) & 0xFFFFFFFF) | (x >> (32 - s));
46}
47
48static inline u32 F(u32 x, u32 y, u32 z)
49{
50 return (x & y) | ((~x) & z);
51}
52
53static inline u32 G(u32 x, u32 y, u32 z)
54{
55 return (x & y) | (x & z) | (y & z);
56}
57
58static inline u32 H(u32 x, u32 y, u32 z)
59{
60 return x ^ y ^ z;
61}
62
63#define ROUND1(a,b,c,d,k,s) (a = lshift(a + F(b,c,d) + k, s))
64#define ROUND2(a,b,c,d,k,s) (a = lshift(a + G(b,c,d) + k + (u32)0x5A827999,s))
65#define ROUND3(a,b,c,d,k,s) (a = lshift(a + H(b,c,d) + k + (u32)0x6ED9EBA1,s))
66
67static void md4_transform(u32 *hash, u32 const *in)
68{
69 u32 a, b, c, d;
70
71 a = hash[0];
72 b = hash[1];
73 c = hash[2];
74 d = hash[3];
75
76 ROUND1(a, b, c, d, in[0], 3);
77 ROUND1(d, a, b, c, in[1], 7);
78 ROUND1(c, d, a, b, in[2], 11);
79 ROUND1(b, c, d, a, in[3], 19);
80 ROUND1(a, b, c, d, in[4], 3);
81 ROUND1(d, a, b, c, in[5], 7);
82 ROUND1(c, d, a, b, in[6], 11);
83 ROUND1(b, c, d, a, in[7], 19);
84 ROUND1(a, b, c, d, in[8], 3);
85 ROUND1(d, a, b, c, in[9], 7);
86 ROUND1(c, d, a, b, in[10], 11);
87 ROUND1(b, c, d, a, in[11], 19);
88 ROUND1(a, b, c, d, in[12], 3);
89 ROUND1(d, a, b, c, in[13], 7);
90 ROUND1(c, d, a, b, in[14], 11);
91 ROUND1(b, c, d, a, in[15], 19);
92
93 ROUND2(a, b, c, d,in[ 0], 3);
94 ROUND2(d, a, b, c, in[4], 5);
95 ROUND2(c, d, a, b, in[8], 9);
96 ROUND2(b, c, d, a, in[12], 13);
97 ROUND2(a, b, c, d, in[1], 3);
98 ROUND2(d, a, b, c, in[5], 5);
99 ROUND2(c, d, a, b, in[9], 9);
100 ROUND2(b, c, d, a, in[13], 13);
101 ROUND2(a, b, c, d, in[2], 3);
102 ROUND2(d, a, b, c, in[6], 5);
103 ROUND2(c, d, a, b, in[10], 9);
104 ROUND2(b, c, d, a, in[14], 13);
105 ROUND2(a, b, c, d, in[3], 3);
106 ROUND2(d, a, b, c, in[7], 5);
107 ROUND2(c, d, a, b, in[11], 9);
108 ROUND2(b, c, d, a, in[15], 13);
109
110 ROUND3(a, b, c, d,in[ 0], 3);
111 ROUND3(d, a, b, c, in[8], 9);
112 ROUND3(c, d, a, b, in[4], 11);
113 ROUND3(b, c, d, a, in[12], 15);
114 ROUND3(a, b, c, d, in[2], 3);
115 ROUND3(d, a, b, c, in[10], 9);
116 ROUND3(c, d, a, b, in[6], 11);
117 ROUND3(b, c, d, a, in[14], 15);
118 ROUND3(a, b, c, d, in[1], 3);
119 ROUND3(d, a, b, c, in[9], 9);
120 ROUND3(c, d, a, b, in[5], 11);
121 ROUND3(b, c, d, a, in[13], 15);
122 ROUND3(a, b, c, d, in[3], 3);
123 ROUND3(d, a, b, c, in[11], 9);
124 ROUND3(c, d, a, b, in[7], 11);
125 ROUND3(b, c, d, a, in[15], 15);
126
127 hash[0] += a;
128 hash[1] += b;
129 hash[2] += c;
130 hash[3] += d;
131}
132
133static inline void md4_transform_helper(struct md4_ctx *ctx)
134{
135 le32_to_cpu_array(ctx->block, ARRAY_SIZE(ctx->block));
136 md4_transform(ctx->hash, ctx->block);
137}
138
139static int md4_init(struct shash_desc *desc)
140{
141 struct md4_ctx *mctx = shash_desc_ctx(desc);
142
143 mctx->hash[0] = 0x67452301;
144 mctx->hash[1] = 0xefcdab89;
145 mctx->hash[2] = 0x98badcfe;
146 mctx->hash[3] = 0x10325476;
147 mctx->byte_count = 0;
148
149 return 0;
150}
151
152static int md4_update(struct shash_desc *desc, const u8 *data, unsigned int len)
153{
154 struct md4_ctx *mctx = shash_desc_ctx(desc);
155 const u32 avail = sizeof(mctx->block) - (mctx->byte_count & 0x3f);
156
157 mctx->byte_count += len;
158
159 if (avail > len) {
160 memcpy((char *)mctx->block + (sizeof(mctx->block) - avail),
161 data, len);
162 return 0;
163 }
164
165 memcpy((char *)mctx->block + (sizeof(mctx->block) - avail),
166 data, avail);
167
168 md4_transform_helper(mctx);
169 data += avail;
170 len -= avail;
171
172 while (len >= sizeof(mctx->block)) {
173 memcpy(mctx->block, data, sizeof(mctx->block));
174 md4_transform_helper(mctx);
175 data += sizeof(mctx->block);
176 len -= sizeof(mctx->block);
177 }
178
179 memcpy(mctx->block, data, len);
180
181 return 0;
182}
183
184static int md4_final(struct shash_desc *desc, u8 *out)
185{
186 struct md4_ctx *mctx = shash_desc_ctx(desc);
187 const unsigned int offset = mctx->byte_count & 0x3f;
188 char *p = (char *)mctx->block + offset;
189 int padding = 56 - (offset + 1);
190
191 *p++ = 0x80;
192 if (padding < 0) {
193 memset(p, 0x00, padding + sizeof (u64));
194 md4_transform_helper(mctx);
195 p = (char *)mctx->block;
196 padding = 56;
197 }
198
199 memset(p, 0, padding);
200 mctx->block[14] = mctx->byte_count << 3;
201 mctx->block[15] = mctx->byte_count >> 29;
202 le32_to_cpu_array(mctx->block, (sizeof(mctx->block) -
203 sizeof(u64)) / sizeof(u32));
204 md4_transform(mctx->hash, mctx->block);
205 cpu_to_le32_array(mctx->hash, ARRAY_SIZE(mctx->hash));
206 memcpy(out, mctx->hash, sizeof(mctx->hash));
207 memset(mctx, 0, sizeof(*mctx));
208
209 return 0;
210}
211
212static struct shash_alg alg = {
213 .digestsize = MD4_DIGEST_SIZE,
214 .init = md4_init,
215 .update = md4_update,
216 .final = md4_final,
217 .descsize = sizeof(struct md4_ctx),
218 .base = {
219 .cra_name = "md4",
220 .cra_driver_name = "md4-generic",
221 .cra_blocksize = MD4_HMAC_BLOCK_SIZE,
222 .cra_module = THIS_MODULE,
223 }
224};
225
226static int __init md4_mod_init(void)
227{
228 return crypto_register_shash(&alg);
229}
230
231static void __exit md4_mod_fini(void)
232{
233 crypto_unregister_shash(&alg);
234}
235
236subsys_initcall(md4_mod_init);
237module_exit(md4_mod_fini);
238
239MODULE_LICENSE("GPL");
240MODULE_DESCRIPTION("MD4 Message Digest Algorithm");
241MODULE_ALIAS_CRYPTO("md4");
242
