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
28 /* Constants for MD5Transform routine.
29 */
30 #define S11 7
31 #define S12 12
32 #define S13 17
33 #define S14 22
34 #define S21 5
35 #define S22 9
36 #define S23 14
37 #define S24 20
38 #define S31 4
39 #define S32 11
40 #define S33 16
41 #define S34 23
42 #define S41 6
43 #define S42 10
44 #define S43 15
45 #define S44 21
46
47 static void MD5Transform PROTO_LIST ((UINT4 [4], unsigned char [64]));
48 static void Encode PROTO_LIST
49 ((unsigned char *, UINT4 *, unsigned int));
50 static void Decode PROTO_LIST
51 ((UINT4 *, unsigned char *, unsigned int));
52 static void MD5_memcpy PROTO_LIST ((POINTER, POINTER, unsigned int));
53 static void MD5_memset PROTO_LIST ((POINTER, int, unsigned int));
54
55 static unsigned char PADDING[64] = {
56 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
57 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
58 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
59 };
60
61 /* F, G, H and I are basic MD5 functions.
62 */
63 #define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
64 #define G(x, y, z) (((x) & (z)) | ((y) & (~z)))
65 #define H(x, y, z) ((x) ^ (y) ^ (z))
66 #define I(x, y, z) ((y) ^ ((x) | (~z)))
67
68 /* ROTATE_LEFT rotates x left n bits.
69 */
70 #define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
71
72 /* FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4.
73 Rotation is separate from addition to prevent recomputation.
74 */
75 #define FF(a, b, c, d, x, s, ac) { \
76 (a) += F ((b), (c), (d)) + (x) + (UINT4)(ac); \
77 (a) = ROTATE_LEFT ((a), (s)); \
78 (a) += (b); \
79 }
80 #define GG(a, b, c, d, x, s, ac) { \
81 (a) += G ((b), (c), (d)) + (x) + (UINT4)(ac); \
82 (a) = ROTATE_LEFT ((a), (s)); \
83 (a) += (b); \
84 }
85 #define HH(a, b, c, d, x, s, ac) { \
86 (a) += H ((b), (c), (d)) + (x) + (UINT4)(ac); \
87 (a) = ROTATE_LEFT ((a), (s)); \
88 (a) += (b); \
89 }
90 #define II(a, b, c, d, x, s, ac) { \
91 (a) += I ((b), (c), (d)) + (x) + (UINT4)(ac); \
92 (a) = ROTATE_LEFT ((a), (s)); \
93 (a) += (b); \
94 }
95
96 /* MD5 initialization. Begins an MD5 operation, writing a new context.
97 */
MD5Init(context)98 void MD5Init (context)
99 MD5_CTX *context; /* context */
100 {
101 context->count[0] = context->count[1] = 0;
102 /* Load magic initialization constants.
103 */
104 context->state[0] = 0x67452301;
105 context->state[1] = 0xefcdab89;
106 context->state[2] = 0x98badcfe;
107 context->state[3] = 0x10325476;
108 }
109
110 /* MD5 block update operation. Continues an MD5 message-digest
111 operation, processing another message block, and updating the
112 context.
113 */
MD5Update(context,input,inputLen)114 void MD5Update (context, input, inputLen)
115 MD5_CTX *context; /* context */
116 unsigned char *input; /* input block */
117 unsigned int inputLen; /* length of input block */
118 {
119 unsigned int i, index, partLen;
120
121 /* Compute number of bytes mod 64 */
122 index = (unsigned int)((context->count[0] >> 3) & 0x3F);
123
124 /* Update number of bits */
125 if ((context->count[0] += ((UINT4)inputLen << 3))
126 < ((UINT4)inputLen << 3))
127 context->count[1]++;
128 context->count[1] += ((UINT4)inputLen >> 29);
129
130 partLen = 64 - index;
131
132 /* Transform as many times as possible.
133 */
134 if (inputLen >= partLen) {
135 MD5_memcpy
136 ((POINTER)&context->buffer[index], (POINTER)input, partLen);
137 MD5Transform (context->state, context->buffer);
138
139 for (i = partLen; i + 63 < inputLen; i += 64)
140 MD5Transform (context->state, &input[i]);
141
142 index = 0;
143 }
144 else
145 i = 0;
146
147 /* Buffer remaining input */
148 MD5_memcpy
149 ((POINTER)&context->buffer[index], (POINTER)&input[i],
150 inputLen-i);
151 }
152
153 /* MD5 finalization. Ends an MD5 message-digest operation, writing the
154 the message digest and zeroizing the context.
155 */
MD5Final(digest,context)156 void MD5Final (digest, context)
157 unsigned char digest[16]; /* message digest */
158 MD5_CTX *context; /* context */
159 {
160 unsigned char bits[8];
161 unsigned int index, padLen;
162
163 /* Save number of bits */
164 Encode (bits, context->count, 8);
165
166 /* Pad out to 56 mod 64.
167 */
168 index = (unsigned int)((context->count[0] >> 3) & 0x3f);
169 padLen = (index < 56) ? (56 - index) : (120 - index);
170 MD5Update (context, PADDING, padLen);
171
172 /* Append length (before padding) */
173 MD5Update (context, bits, 8);
174 /* Store state in digest */
175 Encode (digest, context->state, 16);
176
177 /* Zeroize sensitive information.
178 */
179 MD5_memset ((POINTER)context, 0, sizeof (*context));
180 }
181
182 /* MD5 basic transformation. Transforms state based on block.
183 */
MD5Transform(state,block)184 static void MD5Transform (state, block)
185 UINT4 state[4];
186 unsigned char block[64];
187 {
188 UINT4 a = state[0], b = state[1], c = state[2], d = state[3], x[16];
189
190 Decode (x, block, 64);
191
192 /* Round 1 */
193 FF (a, b, c, d, x[ 0], S11, 0xd76aa478); /* 1 */
194 FF (d, a, b, c, x[ 1], S12, 0xe8c7b756); /* 2 */
195 FF (c, d, a, b, x[ 2], S13, 0x242070db); /* 3 */
196 FF (b, c, d, a, x[ 3], S14, 0xc1bdceee); /* 4 */
197 FF (a, b, c, d, x[ 4], S11, 0xf57c0faf); /* 5 */
198 FF (d, a, b, c, x[ 5], S12, 0x4787c62a); /* 6 */
199 FF (c, d, a, b, x[ 6], S13, 0xa8304613); /* 7 */
200 FF (b, c, d, a, x[ 7], S14, 0xfd469501); /* 8 */
201 FF (a, b, c, d, x[ 8], S11, 0x698098d8); /* 9 */
202 FF (d, a, b, c, x[ 9], S12, 0x8b44f7af); /* 10 */
203 FF (c, d, a, b, x[10], S13, 0xffff5bb1); /* 11 */
204 FF (b, c, d, a, x[11], S14, 0x895cd7be); /* 12 */
205 FF (a, b, c, d, x[12], S11, 0x6b901122); /* 13 */
206 FF (d, a, b, c, x[13], S12, 0xfd987193); /* 14 */
207 FF (c, d, a, b, x[14], S13, 0xa679438e); /* 15 */
208 FF (b, c, d, a, x[15], S14, 0x49b40821); /* 16 */
209
210 /* Round 2 */
211 GG (a, b, c, d, x[ 1], S21, 0xf61e2562); /* 17 */
212 GG (d, a, b, c, x[ 6], S22, 0xc040b340); /* 18 */
213 GG (c, d, a, b, x[11], S23, 0x265e5a51); /* 19 */
214 GG (b, c, d, a, x[ 0], S24, 0xe9b6c7aa); /* 20 */
215 GG (a, b, c, d, x[ 5], S21, 0xd62f105d); /* 21 */
216 GG (d, a, b, c, x[10], S22, 0x2441453); /* 22 */
217 GG (c, d, a, b, x[15], S23, 0xd8a1e681); /* 23 */
218 GG (b, c, d, a, x[ 4], S24, 0xe7d3fbc8); /* 24 */
219 GG (a, b, c, d, x[ 9], S21, 0x21e1cde6); /* 25 */
220 GG (d, a, b, c, x[14], S22, 0xc33707d6); /* 26 */
221 GG (c, d, a, b, x[ 3], S23, 0xf4d50d87); /* 27 */
222 GG (b, c, d, a, x[ 8], S24, 0x455a14ed); /* 28 */
223 GG (a, b, c, d, x[13], S21, 0xa9e3e905); /* 29 */
224 GG (d, a, b, c, x[ 2], S22, 0xfcefa3f8); /* 30 */
225 GG (c, d, a, b, x[ 7], S23, 0x676f02d9); /* 31 */
226 GG (b, c, d, a, x[12], S24, 0x8d2a4c8a); /* 32 */
227
228 /* Round 3 */
229 HH (a, b, c, d, x[ 5], S31, 0xfffa3942); /* 33 */
230 HH (d, a, b, c, x[ 8], S32, 0x8771f681); /* 34 */
231 HH (c, d, a, b, x[11], S33, 0x6d9d6122); /* 35 */
232 HH (b, c, d, a, x[14], S34, 0xfde5380c); /* 36 */
233 HH (a, b, c, d, x[ 1], S31, 0xa4beea44); /* 37 */
234 HH (d, a, b, c, x[ 4], S32, 0x4bdecfa9); /* 38 */
235 HH (c, d, a, b, x[ 7], S33, 0xf6bb4b60); /* 39 */
236 HH (b, c, d, a, x[10], S34, 0xbebfbc70); /* 40 */
237 HH (a, b, c, d, x[13], S31, 0x289b7ec6); /* 41 */
238 HH (d, a, b, c, x[ 0], S32, 0xeaa127fa); /* 42 */
239 HH (c, d, a, b, x[ 3], S33, 0xd4ef3085); /* 43 */
240 HH (b, c, d, a, x[ 6], S34, 0x4881d05); /* 44 */
241 HH (a, b, c, d, x[ 9], S31, 0xd9d4d039); /* 45 */
242 HH (d, a, b, c, x[12], S32, 0xe6db99e5); /* 46 */
243 HH (c, d, a, b, x[15], S33, 0x1fa27cf8); /* 47 */
244 HH (b, c, d, a, x[ 2], S34, 0xc4ac5665); /* 48 */
245
246 /* Round 4 */
247 II (a, b, c, d, x[ 0], S41, 0xf4292244); /* 49 */
248 II (d, a, b, c, x[ 7], S42, 0x432aff97); /* 50 */
249 II (c, d, a, b, x[14], S43, 0xab9423a7); /* 51 */
250 II (b, c, d, a, x[ 5], S44, 0xfc93a039); /* 52 */
251 II (a, b, c, d, x[12], S41, 0x655b59c3); /* 53 */
252 II (d, a, b, c, x[ 3], S42, 0x8f0ccc92); /* 54 */
253 II (c, d, a, b, x[10], S43, 0xffeff47d); /* 55 */
254 II (b, c, d, a, x[ 1], S44, 0x85845dd1); /* 56 */
255 II (a, b, c, d, x[ 8], S41, 0x6fa87e4f); /* 57 */
256 II (d, a, b, c, x[15], S42, 0xfe2ce6e0); /* 58 */
257 II (c, d, a, b, x[ 6], S43, 0xa3014314); /* 59 */
258 II (b, c, d, a, x[13], S44, 0x4e0811a1); /* 60 */
259 II (a, b, c, d, x[ 4], S41, 0xf7537e82); /* 61 */
260 II (d, a, b, c, x[11], S42, 0xbd3af235); /* 62 */
261 II (c, d, a, b, x[ 2], S43, 0x2ad7d2bb); /* 63 */
262 II (b, c, d, a, x[ 9], S44, 0xeb86d391); /* 64 */
263
264 state[0] += a;
265 state[1] += b;
266 state[2] += c;
267 state[3] += d;
268
269 /* Zeroize sensitive information.
270 */
271 MD5_memset ((POINTER)x, 0, sizeof (x));
272 }
273
274 /* Encodes input (UINT4) into output (unsigned char). Assumes len is
275 a multiple of 4.
276 */
Encode(output,input,len)277 static void Encode (output, input, len)
278 unsigned char *output;
279 UINT4 *input;
280 unsigned int len;
281 {
282 unsigned int i, j;
283
284 for (i = 0, j = 0; j < len; i++, j += 4) {
285 output[j] = (unsigned char)(input[i] & 0xff);
286 output[j+1] = (unsigned char)((input[i] >> 8) & 0xff);
287 output[j+2] = (unsigned char)((input[i] >> 16) & 0xff);
288 output[j+3] = (unsigned char)((input[i] >> 24) & 0xff);
289 }
290 }
291
292 /* Decodes input (unsigned char) into output (UINT4). Assumes len is
293 a multiple of 4.
294 */
Decode(output,input,len)295 static void Decode (output, input, len)
296 UINT4 *output;
297 unsigned char *input;
298 unsigned int len;
299 {
300 unsigned int i, j;
301
302 for (i = 0, j = 0; j < len; i++, j += 4)
303 output[i] = ((UINT4)input[j]) | (((UINT4)input[j+1]) << 8) |
304 (((UINT4)input[j+2]) << 16) | (((UINT4)input[j+3]) << 24);
305 }
306
307 /* Note: Replace "for loop" with standard memcpy if possible.
308 */
309
MD5_memcpy(output,input,len)310 static void MD5_memcpy (output, input, len)
311 POINTER output;
312 POINTER input;
313 unsigned int len;
314 {
315 unsigned int i;
316
317 for (i = 0; i < len; i++)
318 output[i] = input[i];
319 }
320
321 /* Note: Replace "for loop" with standard memset if possible.
322 */
MD5_memset(output,value,len)323 static void MD5_memset (output, value, len)
324 POINTER output;
325 int value;
326 unsigned int len;
327 {
328 unsigned int i;
329
330 for (i = 0; i < len; i++)
331 ((char *)output)[i] = (char)value;
332 }
333