md5.c
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1/*
2 * Copyright (C) 1996-2022 The Squid Software Foundation and contributors
3 *
4 * Squid software is distributed under GPLv2+ license and includes
5 * contributions from numerous individuals and organizations.
6 * Please see the COPYING and CONTRIBUTORS files for details.
7 */
8
9/*
10 * This code implements the MD5 message-digest algorithm.
11 * The algorithm is due to Ron Rivest. This code was
12 * written by Colin Plumb in 1993, no copyright is claimed.
13 * This code is in the public domain; do with it what you wish.
14 *
15 * Equivalent code is available from RSA Data Security, Inc.
16 * This code has been tested against that, and is equivalent,
17 * except that you don't need to include two pages of legalese
18 * with every copy.
19 *
20 * To compute the message digest of a chunk of bytes, declare an
21 * SquidMD5Context structure, pass it to SquidMD5Init, call
22 * SquidMD5Update as needed on buffers full of bytes, and then call
23 * SquidMD5Final, which will fill a supplied 16-byte array with the
24 * digest.
25 *
26 * Changed so as no longer to depend on Colin Plumb's `usual.h' header
27 * definitions; now uses stuff from dpkg's config.h.
28 * - Ian Jackson <ian@chiark.greenend.org.uk>.
29 * Still in the public domain.
30 *
31 * Changed SquidMD5Update to take a void * for easier use and some
32 * other minor cleanup. - Henrik Nordstrom <henrik@henriknordstrom.net>.
33 * Still in the public domain.
34 *
35 * Prefixed all symbols with "Squid" so they don't collide with
36 * other libraries. Duane Wessels <wessels@squid-cache.org>.
37 * Still in the public domain.
38 *
39 */
40#include "squid.h"
41#include "md5.h"
42
43#if !HAVE_NETTLE_MD5_H
44
45#if HAVE_STRING_H
46#include <string.h> /* for memcpy() */
47#endif
48#if HAVE_SYS_TYPES_H
49#include <sys/types.h> /* for stupid systems */
50#endif
51
52#ifdef WORDS_BIGENDIAN
53void
54static byteSwap(uint32_t * buf, unsigned words)
55{
56 uint8_t *p = (uint8_t *) buf;
57
58 do {
59 *buf++ = (uint32_t) ((unsigned) p[3] << 8 | p[2]) << 16 |
60 ((unsigned) p[1] << 8 | p[0]);
61 p += 4;
62 } while (--words);
63}
64#else
65#define byteSwap(buf,words)
66#endif
67
68/*
69 * Start MD5 accumulation. Set bit count to 0 and buffer to mysterious
70 * initialization constants.
71 */
72void
74{
75 ctx->buf[0] = 0x67452301;
76 ctx->buf[1] = 0xefcdab89;
77 ctx->buf[2] = 0x98badcfe;
78 ctx->buf[3] = 0x10325476;
79
80 ctx->bytes[0] = 0;
81 ctx->bytes[1] = 0;
82}
83
84/*
85 * Update context to reflect the concatenation of another buffer full
86 * of bytes.
87 */
88void
89SquidMD5Update(struct SquidMD5Context *ctx, const void *_buf, unsigned len)
90{
91 uint8_t const *buf = _buf;
92 uint32_t t;
93
94 /* Update byte count */
95
96 t = ctx->bytes[0];
97 if ((ctx->bytes[0] = t + len) < t)
98 ctx->bytes[1]++; /* Carry from low to high */
99
100 t = 64 - (t & 0x3f); /* Space available in ctx->in (at least 1) */
101 if (t > len) {
102 memcpy((uint8_t *) ctx->in + 64 - t, buf, len);
103 return;
104 }
105 /* First chunk is an odd size */
106 memcpy((uint8_t *) ctx->in + 64 - t, buf, t);
107 byteSwap(ctx->in, 16);
108 SquidMD5Transform(ctx->buf, ctx->in);
109 buf += t;
110 len -= t;
111
112 /* Process data in 64-byte chunks */
113 while (len >= 64) {
114 memcpy(ctx->in, buf, 64);
115 byteSwap(ctx->in, 16);
116 SquidMD5Transform(ctx->buf, ctx->in);
117 buf += 64;
118 len -= 64;
119 }
120
121 /* Handle any remaining bytes of data. */
122 memcpy(ctx->in, buf, len);
123}
124
125/*
126 * Final wrapup - pad to 64-byte boundary with the bit pattern
127 * 1 0* (64-bit count of bits processed, MSB-first)
128 */
129void
130SquidMD5Final(unsigned char digest[16], struct SquidMD5Context *ctx)
131{
132 int count = ctx->bytes[0] & 0x3f; /* Number of bytes in ctx->in */
133 uint8_t *p = (uint8_t *) ctx->in + count;
134
135 /* Set the first char of padding to 0x80. There is always room. */
136 *p++ = 0x80;
137
138 /* Bytes of padding needed to make 56 bytes (-8..55) */
139 count = 56 - 1 - count;
140
141 if (count < 0) { /* Padding forces an extra block */
142 memset(p, 0, count + 8);
143 byteSwap(ctx->in, 16);
144 SquidMD5Transform(ctx->buf, ctx->in);
145 p = (uint8_t *) ctx->in;
146 count = 56;
147 }
148 memset(p, 0, count);
149 byteSwap(ctx->in, 14);
150
151 /* Append length in bits and transform */
152 ctx->in[14] = ctx->bytes[0] << 3;
153 ctx->in[15] = ctx->bytes[1] << 3 | ctx->bytes[0] >> 29;
154 SquidMD5Transform(ctx->buf, ctx->in);
155
156 byteSwap(ctx->buf, 4);
157 memcpy(digest, ctx->buf, 16);
158 memset(ctx, 0, sizeof(*ctx)); /* In case it's sensitive */
159}
160
161#ifndef ASM_MD5
162
163/* The four core functions - F1 is optimized somewhat */
164
165/* #define F1(x, y, z) (x & y | ~x & z) */
166#define F1(x, y, z) (z ^ (x & (y ^ z)))
167#define F2(x, y, z) F1(z, x, y)
168#define F3(x, y, z) (x ^ y ^ z)
169#define F4(x, y, z) (y ^ (x | ~z))
170
171/* This is the central step in the MD5 algorithm. */
172#define MD5STEP(f,w,x,y,z,in,s) \
173 (w += f(x,y,z) + in, w = (w<<s | w>>(32-s)) + x)
174
175/*
176 * The core of the MD5 algorithm, this alters an existing MD5 hash to
177 * reflect the addition of 16 longwords of new data. SquidMD5Update blocks
178 * the data and converts bytes into longwords for this routine.
179 */
180void
181SquidMD5Transform(uint32_t buf[4], uint32_t const in[16])
182{
183 register uint32_t a, b, c, d;
184
185 a = buf[0];
186 b = buf[1];
187 c = buf[2];
188 d = buf[3];
189
190 MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
191 MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
192 MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
193 MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
194 MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
195 MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
196 MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
197 MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
198 MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
199 MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
200 MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
201 MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
202 MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
203 MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
204 MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
205 MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
206
207 MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
208 MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
209 MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
210 MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
211 MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
212 MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
213 MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
214 MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
215 MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
216 MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
217 MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
218 MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
219 MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
220 MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
221 MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
222 MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
223
224 MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
225 MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
226 MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
227 MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
228 MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
229 MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
230 MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
231 MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
232 MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
233 MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
234 MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
235 MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
236 MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
237 MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
238 MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
239 MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
240
241 MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
242 MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
243 MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
244 MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
245 MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
246 MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
247 MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
248 MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
249 MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
250 MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
251 MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
252 MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
253 MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
254 MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
255 MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
256 MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);
257
258 buf[0] += a;
259 buf[1] += b;
260 buf[2] += c;
261 buf[3] += d;
262}
263
264#endif /* !ASM_MD5 */
265#endif /* HAVE_ETTLE_MD5_H */
266
#define byteSwap(buf, words)
Definition: md5.c:65
#define F1(x, y, z)
Definition: md5.c:166
void SquidMD5Init(struct SquidMD5Context *ctx)
Definition: md5.c:73
#define F4(x, y, z)
Definition: md5.c:169
void SquidMD5Final(unsigned char digest[16], struct SquidMD5Context *ctx)
Definition: md5.c:130
#define F3(x, y, z)
Definition: md5.c:168
void SquidMD5Transform(uint32_t buf[4], uint32_t const in[16])
Definition: md5.c:181
void SquidMD5Update(struct SquidMD5Context *ctx, const void *_buf, unsigned len)
Definition: md5.c:89
#define MD5STEP(f, w, x, y, z, in, s)
Definition: md5.c:172
#define F2(x, y, z)
Definition: md5.c:167
uint32_t bytes[2]
Definition: md5.h:57
uint32_t buf[4]
Definition: md5.h:56
uint32_t in[16]
Definition: md5.h:58

 

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