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md5.c (7869B)
1 #include "libsheepyObject.h"
2
3 typ struct {
4 u32 lo, hi;
5 u32 a, b, c, d;
6 unsigned char buffer[64];
7 u32 block[16];
8 } MD5_CTX;
9
10 /*
11 * The basic MD5 functions.
12 *
13 * F and G are optimized compared to their RFC 1321 definitions for
14 * architectures that lack an AND-NOT instruction, just like in Colin Plumb's
15 * implementation.
16 */
17 #define F(x, y, z) ((z) ^ ((x) & ((y) ^ (z))))
18 #define G(x, y, z) ((y) ^ ((z) & ((x) ^ (y))))
19 #define H(x, y, z) ((x) ^ (y) ^ (z))
20 #define I(x, y, z) ((y) ^ ((x) | ~(z)))
21
22 /*
23 * The MD5 transformation for all four rounds.
24 */
25 #define STEP(f, a, b, c, d, x, t, s) \
26 (a) += f((b), (c), (d)) + (x) + (t); \
27 (a) = (((a) << (s)) | (((a)&0xffffffff) >> (32 - (s)))); \
28 (a) += (b);
29
30 /*
31 * SET reads 4 input bytes in little-endian byte order and stores them
32 * in a properly aligned word in host byte order.
33 *
34 * The check for little-endian architectures that tolerate unaligned
35 * memory accesses is just an optimization. Nothing will break if it
36 * doesn't work.
37 */
38 #if defined(__i386__) || defined(__x86_64__) || defined(__vax__)
39 #define SET(n) (*(u32 *)&ptr[(n)*4])
40 #define GET(n) SET(n)
41 #else
42 #define SET(n) \
43 (ctx->block[(n)] = (u32)ptr[(n)*4] | \
44 ((u32)ptr[(n)*4 + 1] << 8) | \
45 ((u32)ptr[(n)*4 + 2] << 16) | \
46 ((u32)ptr[(n)*4 + 3] << 24))
47 #define GET(n) (ctx->block[(n)])
48 #endif
49
50 /*
51 * This processes one or more 64-byte data blocks, but does NOT update
52 * the bit counters. There are no alignment requirements.
53 */
54 static void *body(MD5_CTX *ctx, void *data, unsigned long size) {
55 unsigned char *ptr;
56 u32 a, b, c, d;
57 u32 saved_a, saved_b, saved_c, saved_d;
58
59 ptr = data;
60
61 a = ctx->a;
62 b = ctx->b;
63 c = ctx->c;
64 d = ctx->d;
65
66 do {
67 saved_a = a;
68 saved_b = b;
69 saved_c = c;
70 saved_d = d;
71
72 /* Round 1 */
73 STEP(F, a, b, c, d, SET(0), 0xd76aa478, 7)
74 STEP(F, d, a, b, c, SET(1), 0xe8c7b756, 12)
75 STEP(F, c, d, a, b, SET(2), 0x242070db, 17)
76 STEP(F, b, c, d, a, SET(3), 0xc1bdceee, 22)
77 STEP(F, a, b, c, d, SET(4), 0xf57c0faf, 7)
78 STEP(F, d, a, b, c, SET(5), 0x4787c62a, 12)
79 STEP(F, c, d, a, b, SET(6), 0xa8304613, 17)
80 STEP(F, b, c, d, a, SET(7), 0xfd469501, 22)
81 STEP(F, a, b, c, d, SET(8), 0x698098d8, 7)
82 STEP(F, d, a, b, c, SET(9), 0x8b44f7af, 12)
83 STEP(F, c, d, a, b, SET(10), 0xffff5bb1, 17)
84 STEP(F, b, c, d, a, SET(11), 0x895cd7be, 22)
85 STEP(F, a, b, c, d, SET(12), 0x6b901122, 7)
86 STEP(F, d, a, b, c, SET(13), 0xfd987193, 12)
87 STEP(F, c, d, a, b, SET(14), 0xa679438e, 17)
88 STEP(F, b, c, d, a, SET(15), 0x49b40821, 22)
89
90 /* Round 2 */
91 STEP(G, a, b, c, d, GET(1), 0xf61e2562, 5)
92 STEP(G, d, a, b, c, GET(6), 0xc040b340, 9)
93 STEP(G, c, d, a, b, GET(11), 0x265e5a51, 14)
94 STEP(G, b, c, d, a, GET(0), 0xe9b6c7aa, 20)
95 STEP(G, a, b, c, d, GET(5), 0xd62f105d, 5)
96 STEP(G, d, a, b, c, GET(10), 0x02441453, 9)
97 STEP(G, c, d, a, b, GET(15), 0xd8a1e681, 14)
98 STEP(G, b, c, d, a, GET(4), 0xe7d3fbc8, 20)
99 STEP(G, a, b, c, d, GET(9), 0x21e1cde6, 5)
100 STEP(G, d, a, b, c, GET(14), 0xc33707d6, 9)
101 STEP(G, c, d, a, b, GET(3), 0xf4d50d87, 14)
102 STEP(G, b, c, d, a, GET(8), 0x455a14ed, 20)
103 STEP(G, a, b, c, d, GET(13), 0xa9e3e905, 5)
104 STEP(G, d, a, b, c, GET(2), 0xfcefa3f8, 9)
105 STEP(G, c, d, a, b, GET(7), 0x676f02d9, 14)
106 STEP(G, b, c, d, a, GET(12), 0x8d2a4c8a, 20)
107
108 /* Round 3 */
109 STEP(H, a, b, c, d, GET(5), 0xfffa3942, 4)
110 STEP(H, d, a, b, c, GET(8), 0x8771f681, 11)
111 STEP(H, c, d, a, b, GET(11), 0x6d9d6122, 16)
112 STEP(H, b, c, d, a, GET(14), 0xfde5380c, 23)
113 STEP(H, a, b, c, d, GET(1), 0xa4beea44, 4)
114 STEP(H, d, a, b, c, GET(4), 0x4bdecfa9, 11)
115 STEP(H, c, d, a, b, GET(7), 0xf6bb4b60, 16)
116 STEP(H, b, c, d, a, GET(10), 0xbebfbc70, 23)
117 STEP(H, a, b, c, d, GET(13), 0x289b7ec6, 4)
118 STEP(H, d, a, b, c, GET(0), 0xeaa127fa, 11)
119 STEP(H, c, d, a, b, GET(3), 0xd4ef3085, 16)
120 STEP(H, b, c, d, a, GET(6), 0x04881d05, 23)
121 STEP(H, a, b, c, d, GET(9), 0xd9d4d039, 4)
122 STEP(H, d, a, b, c, GET(12), 0xe6db99e5, 11)
123 STEP(H, c, d, a, b, GET(15), 0x1fa27cf8, 16)
124 STEP(H, b, c, d, a, GET(2), 0xc4ac5665, 23)
125
126 /* Round 4 */
127 STEP(I, a, b, c, d, GET(0), 0xf4292244, 6)
128 STEP(I, d, a, b, c, GET(7), 0x432aff97, 10)
129 STEP(I, c, d, a, b, GET(14), 0xab9423a7, 15)
130 STEP(I, b, c, d, a, GET(5), 0xfc93a039, 21)
131 STEP(I, a, b, c, d, GET(12), 0x655b59c3, 6)
132 STEP(I, d, a, b, c, GET(3), 0x8f0ccc92, 10)
133 STEP(I, c, d, a, b, GET(10), 0xffeff47d, 15)
134 STEP(I, b, c, d, a, GET(1), 0x85845dd1, 21)
135 STEP(I, a, b, c, d, GET(8), 0x6fa87e4f, 6)
136 STEP(I, d, a, b, c, GET(15), 0xfe2ce6e0, 10)
137 STEP(I, c, d, a, b, GET(6), 0xa3014314, 15)
138 STEP(I, b, c, d, a, GET(13), 0x4e0811a1, 21)
139 STEP(I, a, b, c, d, GET(4), 0xf7537e82, 6)
140 STEP(I, d, a, b, c, GET(11), 0xbd3af235, 10)
141 STEP(I, c, d, a, b, GET(2), 0x2ad7d2bb, 15)
142 STEP(I, b, c, d, a, GET(9), 0xeb86d391, 21)
143
144 a += saved_a;
145 b += saved_b;
146 c += saved_c;
147 d += saved_d;
148
149 ptr += 64;
150 } while (size -= 64);
151
152 ctx->a = a;
153 ctx->b = b;
154 ctx->c = c;
155 ctx->d = d;
156
157 return ptr;
158 }
159
160 void MD5_Init(MD5_CTX *ctx) {
161 ctx->a = 0x67452301;
162 ctx->b = 0xefcdab89;
163 ctx->c = 0x98badcfe;
164 ctx->d = 0x10325476;
165
166 ctx->lo = 0;
167 ctx->hi = 0;
168 }
169
170 void MD5_Update(MD5_CTX *ctx, void *data, unsigned long size) {
171 u32 saved_lo;
172 unsigned long used, free;
173
174 saved_lo = ctx->lo;
175 if ((ctx->lo = (saved_lo + size) & 0x1fffffff) < saved_lo) {
176 ctx->hi++;
177 }
178 ctx->hi += size >> 29;
179
180 used = saved_lo & 0x3f;
181
182 if (used) {
183 free = 64 - used;
184
185 if (size < free) {
186 memcpy(&ctx->buffer[used], data, size);
187 return;
188 }
189
190 memcpy(&ctx->buffer[used], data, free);
191 data = (unsigned char *)data + free;
192 size -= free;
193 body(ctx, ctx->buffer, 64);
194 }
195
196 if (size >= 64) {
197 data = body(ctx, data, size & ~(unsigned long)0x3f);
198 size &= 0x3f;
199 }
200
201 memcpy(ctx->buffer, data, size);
202 }
203
204 void MD5_Final(unsigned char *result, MD5_CTX *ctx) {
205 unsigned long used, free;
206
207 used = ctx->lo & 0x3f;
208
209 ctx->buffer[used++] = 0x80;
210
211 free = 64 - used;
212
213 if (free < 8) {
214 memset(&ctx->buffer[used], 0, free);
215 body(ctx, ctx->buffer, 64);
216 used = 0;
217 free = 64;
218 }
219
220 memset(&ctx->buffer[used], 0, free - 8);
221
222 ctx->lo <<= 3;
223 ctx->buffer[56] = ctx->lo;
224 ctx->buffer[57] = ctx->lo >> 8;
225 ctx->buffer[58] = ctx->lo >> 16;
226 ctx->buffer[59] = ctx->lo >> 24;
227 ctx->buffer[60] = ctx->hi;
228 ctx->buffer[61] = ctx->hi >> 8;
229 ctx->buffer[62] = ctx->hi >> 16;
230 ctx->buffer[63] = ctx->hi >> 24;
231
232 body(ctx, ctx->buffer, 64);
233
234 result[0] = ctx->a;
235 result[1] = ctx->a >> 8;
236 result[2] = ctx->a >> 16;
237 result[3] = ctx->a >> 24;
238 result[4] = ctx->b;
239 result[5] = ctx->b >> 8;
240 result[6] = ctx->b >> 16;
241 result[7] = ctx->b >> 24;
242 result[8] = ctx->c;
243 result[9] = ctx->c >> 8;
244 result[10] = ctx->c >> 16;
245 result[11] = ctx->c >> 24;
246 result[12] = ctx->d;
247 result[13] = ctx->d >> 8;
248 result[14] = ctx->d >> 16;
249 result[15] = ctx->d >> 24;
250
251 memset(ctx, 0, sizeof(*ctx));
252 }
253
254 /*
255 * Just a simple method for getting the signature
256 * result must be == 16
257 */
258 void md5_signature(unsigned char *key, unsigned long length,
259 unsigned char *result) {
260 MD5_CTX my_md5;
261
262 MD5_Init(&my_md5);
263 (void)MD5_Update(&my_md5, key, length);
264 MD5_Final(result, &my_md5);
265 }
266
267 u32 hash_md5(const unsigned char *key, size_t key_length) {
268 unsigned char results[16];
269
270 md5_signature((unsigned char *)key, (unsigned long)key_length, results);
271
272 uint32_t val = ((uint32_t)(results[3] & 0xFF) << 24) |
273 ((uint32_t)(results[2] & 0xFF) << 16) |
274 ((uint32_t)(results[1] & 0xFF) << 8) | (results[0] & 0xFF);
275
276 return val;
277 }