1 /*
2 * This code implements the MD5 message-digest algorithm.
3 * The algorithm is due to Ron Rivest. This code was
4 * written by Colin Plumb in 1993, no copyright is claimed.
5 * This code is in the public domain; do with it what you wish.
6 *
7 * Equivalent code is available from RSA Data Security, Inc.
8 * This code has been tested against that, and is equivalent,
9 * except that you don't need to include two pages of legalese
10 * with every copy.
11 *
12 * To compute the message digest of a chunk of bytes, declare an
13 * MD5Context structure, pass it to MD5Init, call MD5Update as
14 * needed on buffers full of bytes, and then call MD5Final, which
15 * will fill a supplied 16-byte array with the digest.
16 *
17 * Changed so as no longer to depend on Colin Plumb's `usual.h' header
18 * definitions
19 * - Ian Jackson <[email protected]>.
20 * Still in the public domain.
21 */
22
23 #include <string.h> /* for memcpy() */
24
25 #include "common/md5_utils.h"
26
byteSwap(UWORD32 * buf,unsigned words)27 static void byteSwap(UWORD32 *buf, unsigned words) {
28 md5byte *p;
29
30 /* Only swap bytes for big endian machines */
31 int i = 1;
32
33 if (*(char *)&i == 1) return;
34
35 p = (md5byte *)buf;
36
37 do {
38 *buf++ = (UWORD32)((unsigned)p[3] << 8 | p[2]) << 16 |
39 ((unsigned)p[1] << 8 | p[0]);
40 p += 4;
41 } while (--words);
42 }
43
44 /*
45 * Start MD5 accumulation. Set bit count to 0 and buffer to mysterious
46 * initialization constants.
47 */
MD5Init(struct MD5Context * ctx)48 void MD5Init(struct MD5Context *ctx) {
49 ctx->buf[0] = 0x67452301;
50 ctx->buf[1] = 0xefcdab89;
51 ctx->buf[2] = 0x98badcfe;
52 ctx->buf[3] = 0x10325476;
53
54 ctx->bytes[0] = 0;
55 ctx->bytes[1] = 0;
56 }
57
58 /*
59 * Update context to reflect the concatenation of another buffer full
60 * of bytes.
61 */
MD5Update(struct MD5Context * ctx,md5byte const * buf,unsigned len)62 void MD5Update(struct MD5Context *ctx, md5byte const *buf, unsigned len) {
63 UWORD32 t;
64
65 /* Update byte count */
66
67 t = ctx->bytes[0];
68
69 if ((ctx->bytes[0] = t + len) < t)
70 ctx->bytes[1]++; /* Carry from low to high */
71
72 t = 64 - (t & 0x3f); /* Space available in ctx->in (at least 1) */
73
74 if (t > len) {
75 memcpy((md5byte *)ctx->in + 64 - t, buf, len);
76 return;
77 }
78
79 /* First chunk is an odd size */
80 memcpy((md5byte *)ctx->in + 64 - t, buf, t);
81 byteSwap(ctx->in, 16);
82 MD5Transform(ctx->buf, ctx->in);
83 buf += t;
84 len -= t;
85
86 /* Process data in 64-byte chunks */
87 while (len >= 64) {
88 memcpy(ctx->in, buf, 64);
89 byteSwap(ctx->in, 16);
90 MD5Transform(ctx->buf, ctx->in);
91 buf += 64;
92 len -= 64;
93 }
94
95 /* Handle any remaining bytes of data. */
96 memcpy(ctx->in, buf, len);
97 }
98
99 /*
100 * Final wrapup - pad to 64-byte boundary with the bit pattern
101 * 1 0* (64-bit count of bits processed, MSB-first)
102 */
MD5Final(md5byte digest[16],struct MD5Context * ctx)103 void MD5Final(md5byte digest[16], struct MD5Context *ctx) {
104 int count = ctx->bytes[0] & 0x3f; /* Number of bytes in ctx->in */
105 md5byte *p = (md5byte *)ctx->in + count;
106
107 /* Set the first char of padding to 0x80. There is always room. */
108 *p++ = 0x80;
109
110 /* Bytes of padding needed to make 56 bytes (-8..55) */
111 count = 56 - 1 - count;
112
113 if (count < 0) { /* Padding forces an extra block */
114 memset(p, 0, count + 8);
115 byteSwap(ctx->in, 16);
116 MD5Transform(ctx->buf, ctx->in);
117 p = (md5byte *)ctx->in;
118 count = 56;
119 }
120
121 memset(p, 0, count);
122 byteSwap(ctx->in, 14);
123
124 /* Append length in bits and transform */
125 ctx->in[14] = ctx->bytes[0] << 3;
126 ctx->in[15] = ctx->bytes[1] << 3 | ctx->bytes[0] >> 29;
127 MD5Transform(ctx->buf, ctx->in);
128
129 byteSwap(ctx->buf, 4);
130 memcpy(digest, ctx->buf, 16);
131 memset(ctx, 0, sizeof(*ctx)); /* In case it's sensitive */
132 }
133
134 #ifndef ASM_MD5
135
136 /* The four core functions - F1 is optimized somewhat */
137
138 /* #define F1(x, y, z) (x & y | ~x & z) */
139 #define F1(x, y, z) (z ^ (x & (y ^ z)))
140 #define F2(x, y, z) F1(z, x, y)
141 #define F3(x, y, z) (x ^ y ^ z)
142 #define F4(x, y, z) (y ^ (x | ~z))
143
144 /* This is the central step in the MD5 algorithm. */
145 #define MD5STEP(f, w, x, y, z, in, s) \
146 (w += f(x, y, z) + in, w = (w << s | w >> (32 - s)) + x)
147
148 #if defined(__clang__) && defined(__has_attribute)
149 #if __has_attribute(no_sanitize)
150 #define AOM_NO_UNSIGNED_OVERFLOW_CHECK \
151 __attribute__((no_sanitize("unsigned-integer-overflow")))
152 #endif
153 #if __clang_major__ >= 12
154 #define VPX_NO_UNSIGNED_SHIFT_CHECK \
155 __attribute__((no_sanitize("unsigned-shift-base")))
156 #endif // __clang__ >= 12
157 #endif // __clang__
158
159 #ifndef AOM_NO_UNSIGNED_OVERFLOW_CHECK
160 #define AOM_NO_UNSIGNED_OVERFLOW_CHECK
161 #endif
162 #ifndef AOM_NO_UNSIGNED_SHIFT_CHECK
163 #define AOM_NO_UNSIGNED_SHIFT_CHECK
164 #endif
165
166 /*
167 * The core of the MD5 algorithm, this alters an existing MD5 hash to
168 * reflect the addition of 16 longwords of new data. MD5Update blocks
169 * the data and converts bytes into longwords for this routine.
170 */
MD5Transform(UWORD32 buf[4],UWORD32 const in[16])171 AOM_NO_UNSIGNED_OVERFLOW_CHECK AOM_NO_UNSIGNED_SHIFT_CHECK void MD5Transform(
172 UWORD32 buf[4], UWORD32 const in[16]) {
173 register UWORD32 a, b, c, d;
174
175 a = buf[0];
176 b = buf[1];
177 c = buf[2];
178 d = buf[3];
179
180 MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
181 MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
182 MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
183 MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
184 MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
185 MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
186 MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
187 MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
188 MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
189 MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
190 MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
191 MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
192 MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
193 MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
194 MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
195 MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
196
197 MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
198 MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
199 MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
200 MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
201 MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
202 MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
203 MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
204 MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
205 MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
206 MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
207 MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
208 MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
209 MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
210 MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
211 MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
212 MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
213
214 MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
215 MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
216 MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
217 MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
218 MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
219 MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
220 MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
221 MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
222 MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
223 MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
224 MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
225 MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
226 MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
227 MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
228 MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
229 MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
230
231 MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
232 MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
233 MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
234 MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
235 MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
236 MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
237 MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
238 MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
239 MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
240 MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
241 MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
242 MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
243 MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
244 MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
245 MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
246 MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);
247
248 buf[0] += a;
249 buf[1] += b;
250 buf[2] += c;
251 buf[3] += d;
252 }
253
254 #undef AOM_NO_UNSIGNED_OVERFLOW_CHECK
255 #undef AOM_NO_UNSIGNED_SHIFT_CHECK
256
257 #endif
258