1 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 // The original file was copied from sqlite, and was in the public domain.
6
7 /*
8 * This code implements the MD5 message-digest algorithm.
9 * The algorithm is due to Ron Rivest. This code was
10 * written by Colin Plumb in 1993, no copyright is claimed.
11 * This code is in the public domain; do with it what you wish.
12 *
13 * Equivalent code is available from RSA Data Security, Inc.
14 * This code has been tested against that, and is equivalent,
15 * except that you don't need to include two pages of legalese
16 * with every copy.
17 *
18 * To compute the message digest of a chunk of bytes, declare an
19 * MD5Context structure, pass it to MD5Init, call MD5Update as
20 * needed on buffers full of bytes, and then call MD5Final, which
21 * will fill a supplied 16-byte array with the digest.
22 */
23
24 #include "base/md5.h"
25
26 #include <stddef.h>
27 #include <string.h>
28
29 namespace {
30
31 struct Context {
32 uint32_t buf[4];
33 uint32_t bits[2];
34 uint8_t in[64];
35 };
36
37 /*
38 * Note: this code is harmless on little-endian machines.
39 */
byteReverse(uint8_t * buf,unsigned longs)40 void byteReverse(uint8_t* buf, unsigned longs) {
41 do {
42 uint32_t temp =
43 static_cast<uint32_t>(static_cast<unsigned>(buf[3]) << 8 | buf[2])
44 << 16 |
45 (static_cast<unsigned>(buf[1]) << 8 | buf[0]);
46 *reinterpret_cast<uint32_t*>(buf) = temp;
47 buf += 4;
48 } while (--longs);
49 }
50
51 /* The four core functions - F1 is optimized somewhat */
52
53 /* #define F1(x, y, z) (x & y | ~x & z) */
54 #define F1(x, y, z) (z ^ (x & (y ^ z)))
55 #define F2(x, y, z) F1(z, x, y)
56 #define F3(x, y, z) (x ^ y ^ z)
57 #define F4(x, y, z) (y ^ (x | ~z))
58
59 /* This is the central step in the MD5 algorithm. */
60 #define MD5STEP(f, w, x, y, z, data, s) \
61 (w += f(x, y, z) + data, w = w << s | w >> (32 - s), w += x)
62
63 /*
64 * The core of the MD5 algorithm, this alters an existing MD5 hash to
65 * reflect the addition of 16 longwords of new data. MD5Update blocks
66 * the data and converts bytes into longwords for this routine.
67 */
MD5Transform(uint32_t buf[4],const uint32_t in[16])68 void MD5Transform(uint32_t buf[4], const uint32_t in[16]) {
69 uint32_t a, b, c, d;
70
71 a = buf[0];
72 b = buf[1];
73 c = buf[2];
74 d = buf[3];
75
76 MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
77 MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
78 MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
79 MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
80 MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
81 MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
82 MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
83 MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
84 MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
85 MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
86 MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
87 MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
88 MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
89 MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
90 MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
91 MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
92
93 MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
94 MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
95 MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
96 MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
97 MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
98 MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
99 MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
100 MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
101 MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
102 MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
103 MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
104 MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
105 MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
106 MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
107 MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
108 MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
109
110 MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
111 MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
112 MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
113 MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
114 MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
115 MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
116 MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
117 MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
118 MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
119 MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
120 MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
121 MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
122 MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
123 MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
124 MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
125 MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
126
127 MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
128 MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
129 MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
130 MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
131 MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
132 MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
133 MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
134 MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
135 MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
136 MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
137 MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
138 MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
139 MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
140 MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
141 MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
142 MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);
143
144 buf[0] += a;
145 buf[1] += b;
146 buf[2] += c;
147 buf[3] += d;
148 }
149
150 } // namespace
151
152 namespace base {
153
154 /*
155 * Start MD5 accumulation. Set bit count to 0 and buffer to mysterious
156 * initialization constants.
157 */
MD5Init(MD5Context * context)158 void MD5Init(MD5Context* context) {
159 struct Context* ctx = reinterpret_cast<struct Context*>(context);
160 ctx->buf[0] = 0x67452301;
161 ctx->buf[1] = 0xefcdab89;
162 ctx->buf[2] = 0x98badcfe;
163 ctx->buf[3] = 0x10325476;
164 ctx->bits[0] = 0;
165 ctx->bits[1] = 0;
166 }
167
168 /*
169 * Update context to reflect the concatenation of another buffer full
170 * of bytes.
171 */
MD5Update(MD5Context * context,std::string_view data)172 void MD5Update(MD5Context* context, std::string_view data) {
173 struct Context* ctx = reinterpret_cast<struct Context*>(context);
174 const uint8_t* buf = reinterpret_cast<const uint8_t*>(data.data());
175 size_t len = data.size();
176
177 /* Update bitcount */
178
179 uint32_t t = ctx->bits[0];
180 if ((ctx->bits[0] = t + (static_cast<uint32_t>(len) << 3)) < t)
181 ctx->bits[1]++; /* Carry from low to high */
182 ctx->bits[1] += static_cast<uint32_t>(len >> 29);
183
184 t = (t >> 3) & 0x3f; /* Bytes already in shsInfo->data */
185
186 /* Handle any leading odd-sized chunks */
187
188 if (t) {
189 uint8_t* p = static_cast<uint8_t*>(ctx->in + t);
190
191 t = 64 - t;
192 if (len < t) {
193 memcpy(p, buf, len);
194 return;
195 }
196 memcpy(p, buf, t);
197 byteReverse(ctx->in, 16);
198 MD5Transform(ctx->buf, reinterpret_cast<uint32_t*>(ctx->in));
199 buf += t;
200 len -= t;
201 }
202
203 /* Process data in 64-byte chunks */
204
205 while (len >= 64) {
206 memcpy(ctx->in, buf, 64);
207 byteReverse(ctx->in, 16);
208 MD5Transform(ctx->buf, reinterpret_cast<uint32_t*>(ctx->in));
209 buf += 64;
210 len -= 64;
211 }
212
213 /* Handle any remaining bytes of data. */
214
215 memcpy(ctx->in, buf, len);
216 }
217
218 /*
219 * Final wrapup - pad to 64-byte boundary with the bit pattern
220 * 1 0* (64-bit count of bits processed, MSB-first)
221 */
MD5Final(MD5Digest * digest,MD5Context * context)222 void MD5Final(MD5Digest* digest, MD5Context* context) {
223 struct Context* ctx = reinterpret_cast<struct Context*>(context);
224 unsigned count;
225 uint8_t* p;
226
227 /* Compute number of bytes mod 64 */
228 count = (ctx->bits[0] >> 3) & 0x3F;
229
230 /* Set the first char of padding to 0x80. This is safe since there is
231 always at least one byte free */
232 p = ctx->in + count;
233 *p++ = 0x80;
234
235 /* Bytes of padding needed to make 64 bytes */
236 count = 64 - 1 - count;
237
238 /* Pad out to 56 mod 64 */
239 if (count < 8) {
240 /* Two lots of padding: Pad the first block to 64 bytes */
241 memset(p, 0, count);
242 byteReverse(ctx->in, 16);
243 MD5Transform(ctx->buf, reinterpret_cast<uint32_t*>(ctx->in));
244
245 /* Now fill the next block with 56 bytes */
246 memset(ctx->in, 0, 56);
247 } else {
248 /* Pad block to 56 bytes */
249 memset(p, 0, count - 8);
250 }
251 byteReverse(ctx->in, 14);
252
253 /* Append length in bits and transform */
254 memcpy(&ctx->in[14 * sizeof(ctx->bits[0])], &ctx->bits[0],
255 sizeof(ctx->bits[0]));
256 memcpy(&ctx->in[15 * sizeof(ctx->bits[1])], &ctx->bits[1],
257 sizeof(ctx->bits[1]));
258
259 MD5Transform(ctx->buf, reinterpret_cast<uint32_t*>(ctx->in));
260 byteReverse(reinterpret_cast<uint8_t*>(ctx->buf), 4);
261 memcpy(digest->a, ctx->buf, 16);
262 memset(ctx, 0, sizeof(*ctx)); /* In case it's sensitive */
263 }
264
MD5IntermediateFinal(MD5Digest * digest,const MD5Context * context)265 void MD5IntermediateFinal(MD5Digest* digest, const MD5Context* context) {
266 /* MD5Final mutates the MD5Context*. Make a copy for generating the
267 intermediate value. */
268 MD5Context context_copy;
269 memcpy(&context_copy, context, sizeof(context_copy));
270 MD5Final(digest, &context_copy);
271 }
272
MD5DigestToBase16(const MD5Digest & digest)273 std::string MD5DigestToBase16(const MD5Digest& digest) {
274 static char const zEncode[] = "0123456789abcdef";
275
276 std::string ret;
277 ret.resize(32);
278
279 for (int i = 0, j = 0; i < 16; i++, j += 2) {
280 uint8_t a = digest.a[i];
281 ret[j] = zEncode[(a >> 4) & 0xf];
282 ret[j + 1] = zEncode[a & 0xf];
283 }
284 return ret;
285 }
286
MD5Sum(const void * data,size_t length,MD5Digest * digest)287 void MD5Sum(const void* data, size_t length, MD5Digest* digest) {
288 MD5Context ctx;
289 MD5Init(&ctx);
290 MD5Update(&ctx,
291 std::string_view(reinterpret_cast<const char*>(data), length));
292 MD5Final(digest, &ctx);
293 }
294
MD5String(std::string_view str)295 std::string MD5String(std::string_view str) {
296 MD5Digest digest;
297 MD5Sum(str.data(), str.length(), &digest);
298 return MD5DigestToBase16(digest);
299 }
300
301 } // namespace base
302