Line data Source code
1 : /* MD5C.C - RSA Data Security, Inc., MD5 message-digest algorithm
2 : */
3 :
4 : /* Copyright (C) 1991-2, RSA Data Security, Inc. Created 1991. All
5 : rights reserved.
6 :
7 : License to copy and use this software is granted provided that it
8 : is identified as the "RSA Data Security, Inc. MD5 Message-Digest
9 : Algorithm" in all material mentioning or referencing this software
10 : or this function.
11 :
12 : License is also granted to make and use derivative works provided
13 : that such works are identified as "derived from the RSA Data
14 : Security, Inc. MD5 Message-Digest Algorithm" in all material
15 : mentioning or referencing the derived work.
16 :
17 : RSA Data Security, Inc. makes no representations concerning either
18 : the merchantability of this software or the suitability of this
19 : software for any particular purpose. It is provided "as is"
20 : without express or implied warranty of any kind.
21 :
22 : These notices must be retained in any copies of any part of this
23 : documentation and/or software.
24 : */
25 :
26 : #include "md5.h"
27 : #include <string.h>
28 :
29 : /* Constants for MD5Transform routine.
30 : */
31 :
32 : #define S11 7
33 : #define S12 12
34 : #define S13 17
35 : #define S14 22
36 : #define S21 5
37 : #define S22 9
38 : #define S23 14
39 : #define S24 20
40 : #define S31 4
41 : #define S32 11
42 : #define S33 16
43 : #define S34 23
44 : #define S41 6
45 : #define S42 10
46 : #define S43 15
47 : #define S44 21
48 :
49 : static void MD5Transform(uint32_t [4], const uint8_t [64]);
50 : static void Encode(uint8_t *, const uint32_t *, unsigned int);
51 : static void Decode(uint32_t *, const uint8_t *, unsigned int);
52 :
53 : static uint8_t PADDING[64] = {
54 : 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
55 : 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
56 : 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
57 : };
58 :
59 : /* F, G, H and I are basic MD5 functions.
60 : */
61 : #define F(x, y, z)(((x) & (y)) | ((~x) & (z)))
62 : #define G(x, y, z) (((x) & (z)) | ((y) & (~z)))
63 : #define H(x, y, z) ((x) ^ (y) ^ (z))
64 : #define I(x, y, z) ((y) ^ ((x) | (~z)))
65 :
66 : /* ROTATE_LEFT rotates x left n bits.
67 : */
68 : #define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
69 :
70 : /* FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4.
71 : Rotation is separate from addition to prevent recomputation.
72 : */
73 : #define FF(a, b, c, d, x, s, ac) { \
74 : (a) += F((b), (c), (d)) + (x) + (uint32_t)(ac); \
75 : (a) = ROTATE_LEFT((a), (s)); \
76 : (a) += (b); \
77 : }
78 : #define GG(a, b, c, d, x, s, ac) { \
79 : (a) += G((b), (c), (d)) + (x) + (uint32_t)(ac); \
80 : (a) = ROTATE_LEFT((a), (s)); \
81 : (a) += (b); \
82 : }
83 : #define HH(a, b, c, d, x, s, ac) { \
84 : (a) += H((b), (c), (d)) + (x) + (uint32_t)(ac); \
85 : (a) = ROTATE_LEFT((a), (s)); \
86 : (a) += (b); \
87 : }
88 : #define II(a, b, c, d, x, s, ac) { \
89 : (a) += I((b), (c), (d)) + (x) + (uint32_t)(ac); \
90 : (a) = ROTATE_LEFT((a), (s)); \
91 : (a) += (b); \
92 : }
93 :
94 : /* MD5 initialization. Begins an MD5 operation, writing a new context.
95 : */
96 13 : void MD5Init(MD5_CTX *context)
97 : {
98 13 : context->count[0] = context->count[1] = 0;
99 : /* Load magic initialization constants.
100 : */
101 13 : context->state[0] = 0x67452301;
102 13 : context->state[1] = 0xefcdab89;
103 13 : context->state[2] = 0x98badcfe;
104 13 : context->state[3] = 0x10325476;
105 13 : }
106 :
107 : /* MD5 block update operation. Continues an MD5 message-digest
108 : operation, processing another message block, and updating the
109 : context.
110 : */
111 39 : void MD5Update(
112 : MD5_CTX *context, /* context */
113 : const uint8_t *input, /* input block */
114 : unsigned int inputLen) /* length of input block */
115 : {
116 39 : unsigned int i, index, partLen;
117 :
118 : /* Compute number of bytes mod 64 */
119 39 : index = (unsigned int)((context->count[0] >> 3) & 0x3F);
120 :
121 : /* Update number of bits */
122 39 : if ((context->count[0] += ((uint32_t)inputLen << 3))
123 : < ((uint32_t)inputLen << 3))
124 0 : context->count[1]++;
125 39 : context->count[1] += ((uint32_t)inputLen >> 29);
126 :
127 39 : partLen = 64 - index;
128 :
129 : /* Transform as many times as possible.
130 : */
131 39 : if (inputLen >= partLen) {
132 15 : memcpy(&context->buffer[index], input, partLen);
133 15 : MD5Transform(context->state, context->buffer);
134 :
135 30 : for (i = partLen; i + 63 < inputLen; i += 64)
136 0 : MD5Transform(context->state, &input[i]);
137 :
138 : index = 0;
139 : }
140 : else
141 : i = 0;
142 :
143 : /* Buffer remaining input */
144 39 : memcpy(&context->buffer[index], &input[i], inputLen-i);
145 39 : }
146 :
147 : /* MD5 finalization. Ends an MD5 message-digest operation, writing the
148 : the message digest and zeroizing the context.
149 : */
150 13 : void MD5Final(
151 : uint8_t digest[16], /* message digest */
152 : MD5_CTX *context) /* context */
153 : {
154 13 : uint8_t bits[8];
155 13 : unsigned int index, padLen;
156 :
157 : /* Save number of bits */
158 13 : Encode(bits, context->count, 8);
159 :
160 : /* Pad out to 56 mod 64.
161 : */
162 13 : index = (unsigned int)((context->count[0] >> 3) & 0x3f);
163 13 : padLen = (index < 56) ? (56 - index) : (120 - index);
164 13 : MD5Update(context, PADDING, padLen);
165 :
166 : /* Append length (before padding) */
167 13 : MD5Update(context, bits, 8);
168 : /* Store state in digest */
169 13 : Encode(digest, context->state, 16);
170 :
171 : /* Zeroize sensitive information.
172 : */
173 13 : memset(context, 0, sizeof(*context));
174 13 : }
175 :
176 : /* MD5 basic transformation. Transforms state based on block.
177 : */
178 15 : static void MD5Transform(uint32_t state[4], const uint8_t block[64])
179 : {
180 15 : uint32_t a = state[0], b = state[1], c = state[2], d = state[3], x[16];
181 :
182 15 : Decode(x, block, 64);
183 :
184 : /* Round 1 */
185 15 : FF(a, b, c, d, x[ 0], S11, 0xd76aa478); /* 1 */
186 15 : FF(d, a, b, c, x[ 1], S12, 0xe8c7b756); /* 2 */
187 15 : FF(c, d, a, b, x[ 2], S13, 0x242070db); /* 3 */
188 15 : FF(b, c, d, a, x[ 3], S14, 0xc1bdceee); /* 4 */
189 15 : FF(a, b, c, d, x[ 4], S11, 0xf57c0faf); /* 5 */
190 15 : FF(d, a, b, c, x[ 5], S12, 0x4787c62a); /* 6 */
191 15 : FF(c, d, a, b, x[ 6], S13, 0xa8304613); /* 7 */
192 15 : FF(b, c, d, a, x[ 7], S14, 0xfd469501); /* 8 */
193 15 : FF(a, b, c, d, x[ 8], S11, 0x698098d8); /* 9 */
194 15 : FF(d, a, b, c, x[ 9], S12, 0x8b44f7af); /* 10 */
195 15 : FF(c, d, a, b, x[10], S13, 0xffff5bb1); /* 11 */
196 15 : FF(b, c, d, a, x[11], S14, 0x895cd7be); /* 12 */
197 15 : FF(a, b, c, d, x[12], S11, 0x6b901122); /* 13 */
198 15 : FF(d, a, b, c, x[13], S12, 0xfd987193); /* 14 */
199 15 : FF(c, d, a, b, x[14], S13, 0xa679438e); /* 15 */
200 15 : FF(b, c, d, a, x[15], S14, 0x49b40821); /* 16 */
201 :
202 : /* Round 2 */
203 15 : GG(a, b, c, d, x[ 1], S21, 0xf61e2562); /* 17 */
204 15 : GG(d, a, b, c, x[ 6], S22, 0xc040b340); /* 18 */
205 15 : GG(c, d, a, b, x[11], S23, 0x265e5a51); /* 19 */
206 15 : GG(b, c, d, a, x[ 0], S24, 0xe9b6c7aa); /* 20 */
207 15 : GG(a, b, c, d, x[ 5], S21, 0xd62f105d); /* 21 */
208 15 : GG(d, a, b, c, x[10], S22, 0x2441453); /* 22 */
209 15 : GG(c, d, a, b, x[15], S23, 0xd8a1e681); /* 23 */
210 15 : GG(b, c, d, a, x[ 4], S24, 0xe7d3fbc8); /* 24 */
211 15 : GG(a, b, c, d, x[ 9], S21, 0x21e1cde6); /* 25 */
212 15 : GG(d, a, b, c, x[14], S22, 0xc33707d6); /* 26 */
213 15 : GG(c, d, a, b, x[ 3], S23, 0xf4d50d87); /* 27 */
214 15 : GG(b, c, d, a, x[ 8], S24, 0x455a14ed); /* 28 */
215 15 : GG(a, b, c, d, x[13], S21, 0xa9e3e905); /* 29 */
216 15 : GG(d, a, b, c, x[ 2], S22, 0xfcefa3f8); /* 30 */
217 15 : GG(c, d, a, b, x[ 7], S23, 0x676f02d9); /* 31 */
218 15 : GG(b, c, d, a, x[12], S24, 0x8d2a4c8a); /* 32 */
219 :
220 : /* Round 3 */
221 15 : HH(a, b, c, d, x[ 5], S31, 0xfffa3942); /* 33 */
222 15 : HH(d, a, b, c, x[ 8], S32, 0x8771f681); /* 34 */
223 15 : HH(c, d, a, b, x[11], S33, 0x6d9d6122); /* 35 */
224 15 : HH(b, c, d, a, x[14], S34, 0xfde5380c); /* 36 */
225 15 : HH(a, b, c, d, x[ 1], S31, 0xa4beea44); /* 37 */
226 15 : HH(d, a, b, c, x[ 4], S32, 0x4bdecfa9); /* 38 */
227 15 : HH(c, d, a, b, x[ 7], S33, 0xf6bb4b60); /* 39 */
228 15 : HH(b, c, d, a, x[10], S34, 0xbebfbc70); /* 40 */
229 15 : HH(a, b, c, d, x[13], S31, 0x289b7ec6); /* 41 */
230 15 : HH(d, a, b, c, x[ 0], S32, 0xeaa127fa); /* 42 */
231 15 : HH(c, d, a, b, x[ 3], S33, 0xd4ef3085); /* 43 */
232 15 : HH(b, c, d, a, x[ 6], S34, 0x4881d05); /* 44 */
233 15 : HH(a, b, c, d, x[ 9], S31, 0xd9d4d039); /* 45 */
234 15 : HH(d, a, b, c, x[12], S32, 0xe6db99e5); /* 46 */
235 15 : HH(c, d, a, b, x[15], S33, 0x1fa27cf8); /* 47 */
236 15 : HH(b, c, d, a, x[ 2], S34, 0xc4ac5665); /* 48 */
237 :
238 : /* Round 4 */
239 15 : II(a, b, c, d, x[ 0], S41, 0xf4292244); /* 49 */
240 15 : II(d, a, b, c, x[ 7], S42, 0x432aff97); /* 50 */
241 15 : II(c, d, a, b, x[14], S43, 0xab9423a7); /* 51 */
242 15 : II(b, c, d, a, x[ 5], S44, 0xfc93a039); /* 52 */
243 15 : II(a, b, c, d, x[12], S41, 0x655b59c3); /* 53 */
244 15 : II(d, a, b, c, x[ 3], S42, 0x8f0ccc92); /* 54 */
245 15 : II(c, d, a, b, x[10], S43, 0xffeff47d); /* 55 */
246 15 : II(b, c, d, a, x[ 1], S44, 0x85845dd1); /* 56 */
247 15 : II(a, b, c, d, x[ 8], S41, 0x6fa87e4f); /* 57 */
248 15 : II(d, a, b, c, x[15], S42, 0xfe2ce6e0); /* 58 */
249 15 : II(c, d, a, b, x[ 6], S43, 0xa3014314); /* 59 */
250 15 : II(b, c, d, a, x[13], S44, 0x4e0811a1); /* 60 */
251 15 : II(a, b, c, d, x[ 4], S41, 0xf7537e82); /* 61 */
252 15 : II(d, a, b, c, x[11], S42, 0xbd3af235); /* 62 */
253 15 : II(c, d, a, b, x[ 2], S43, 0x2ad7d2bb); /* 63 */
254 15 : II(b, c, d, a, x[ 9], S44, 0xeb86d391); /* 64 */
255 :
256 15 : state[0] += a;
257 15 : state[1] += b;
258 15 : state[2] += c;
259 15 : state[3] += d;
260 :
261 : /* Zeroize sensitive information.
262 : */
263 15 : memset(x, 0, sizeof(x));
264 15 : }
265 :
266 : /* Encodes input (uint32_t) into output (uint8_t). Assumes len is
267 : a multiple of 4.
268 : */
269 26 : static void Encode(uint8_t *output, const uint32_t *input, unsigned int len)
270 : {
271 26 : unsigned int i, j;
272 :
273 104 : for (i = 0, j = 0; j < len; i++, j += 4) {
274 78 : output[j] = (uint8_t)(input[i] & 0xff);
275 78 : output[j+1] = (uint8_t)((input[i] >> 8) & 0xff);
276 78 : output[j+2] = (uint8_t)((input[i] >> 16) & 0xff);
277 78 : output[j+3] = (uint8_t)((input[i] >> 24) & 0xff);
278 : }
279 26 : }
280 :
281 : /* Decodes input (uint8_t) into output (uint32_t). Assumes len is
282 : a multiple of 4.
283 : */
284 15 : static void Decode(uint32_t *output, const uint8_t *input, unsigned int len)
285 : {
286 15 : unsigned int i, j;
287 :
288 255 : for (i = 0, j = 0; j < len; i++, j += 4)
289 240 : output[i] = ((uint32_t)input[j]) | (((uint32_t)input[j+1]) << 8) |
290 240 : (((uint32_t)input[j+2]) << 16) | (((uint32_t)input[j+3]) << 24);
291 15 : }
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