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 #include "q_shared.h"
18 #include "qcommon.h"
19
20 typedef struct MD5Context {
21 uint32_t buf[4];
22 uint32_t bits[2];
23 unsigned char in[64];
24 } MD5_CTX;
25
26 #ifndef Q3_BIG_ENDIAN
27 #define byteReverse(buf, len) /* Nothing */
28 #else
29 static void byteReverse(unsigned char *buf, unsigned longs);
30
31 /*
32 * Note: this code is harmless on little-endian machines.
33 */
byteReverse(unsigned char * buf,unsigned longs)34 static void byteReverse(unsigned char *buf, unsigned longs)
35 {
36 uint32_t t;
37 do {
38 t = (uint32_t)
39 ((unsigned) buf[3] << 8 | buf[2]) << 16 |
40 ((unsigned) buf[1] << 8 | buf[0]);
41 *(uint32_t *) buf = t;
42 buf += 4;
43 } while (--longs);
44 }
45 #endif // Q3_BIG_ENDIAN
46
47 /*
48 * Start MD5 accumulation. Set bit count to 0 and buffer to mysterious
49 * initialization constants.
50 */
MD5Init(struct MD5Context * ctx)51 static void MD5Init(struct MD5Context *ctx)
52 {
53 ctx->buf[0] = 0x67452301;
54 ctx->buf[1] = 0xefcdab89;
55 ctx->buf[2] = 0x98badcfe;
56 ctx->buf[3] = 0x10325476;
57
58 ctx->bits[0] = 0;
59 ctx->bits[1] = 0;
60 }
61 /* The four core functions - F1 is optimized somewhat */
62
63 /* #define F1(x, y, z) (x & y | ~x & z) */
64 #define F1(x, y, z) (z ^ (x & (y ^ z)))
65 #define F2(x, y, z) F1(z, x, y)
66 #define F3(x, y, z) (x ^ y ^ z)
67 #define F4(x, y, z) (y ^ (x | ~z))
68
69 /* This is the central step in the MD5 algorithm. */
70 #define MD5STEP(f, w, x, y, z, data, s) \
71 ( w += f(x, y, z) + data, w = w<<s | w>>(32-s), w += x )
72
73 /*
74 * The core of the MD5 algorithm, this alters an existing MD5 hash to
75 * reflect the addition of 16 longwords of new data. MD5Update blocks
76 * the data and converts bytes into longwords for this routine.
77 */
MD5Transform(uint32_t buf[4],uint32_t const in[16])78 static void MD5Transform(uint32_t buf[4],
79 uint32_t const in[16])
80 {
81 register uint32_t a, b, c, d;
82
83 a = buf[0];
84 b = buf[1];
85 c = buf[2];
86 d = buf[3];
87
88 MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
89 MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
90 MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
91 MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
92 MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
93 MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
94 MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
95 MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
96 MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
97 MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
98 MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
99 MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
100 MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
101 MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
102 MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
103 MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
104
105 MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
106 MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
107 MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
108 MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
109 MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
110 MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
111 MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
112 MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
113 MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
114 MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
115 MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
116 MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
117 MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
118 MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
119 MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
120 MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
121
122 MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
123 MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
124 MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
125 MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
126 MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
127 MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
128 MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
129 MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
130 MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
131 MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
132 MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
133 MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
134 MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
135 MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
136 MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
137 MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
138
139 MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
140 MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
141 MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
142 MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
143 MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
144 MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
145 MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
146 MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
147 MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
148 MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
149 MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
150 MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
151 MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
152 MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
153 MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
154 MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);
155
156 buf[0] += a;
157 buf[1] += b;
158 buf[2] += c;
159 buf[3] += d;
160 }
161
162 /*
163 * Update context to reflect the concatenation of another buffer full
164 * of bytes.
165 */
MD5Update(struct MD5Context * ctx,unsigned char const * buf,unsigned len)166 static void MD5Update(struct MD5Context *ctx, unsigned char const *buf,
167 unsigned len)
168 {
169 uint32_t t;
170
171 /* Update bitcount */
172
173 t = ctx->bits[0];
174 if ((ctx->bits[0] = t + ((uint32_t) len << 3)) < t)
175 ctx->bits[1]++; /* Carry from low to high */
176 ctx->bits[1] += len >> 29;
177
178 t = (t >> 3) & 0x3f; /* Bytes already in shsInfo->data */
179
180 /* Handle any leading odd-sized chunks */
181
182 if (t) {
183 unsigned char *p = (unsigned char *) ctx->in + t;
184
185 t = 64 - t;
186 if (len < t) {
187 memcpy(p, buf, len);
188 return;
189 }
190 memcpy(p, buf, t);
191 byteReverse(ctx->in, 16);
192 MD5Transform(ctx->buf, (uint32_t *) ctx->in);
193 buf += t;
194 len -= t;
195 }
196 /* Process data in 64-byte chunks */
197
198 while (len >= 64) {
199 memcpy(ctx->in, buf, 64);
200 byteReverse(ctx->in, 16);
201 MD5Transform(ctx->buf, (uint32_t *) ctx->in);
202 buf += 64;
203 len -= 64;
204 }
205
206 /* Handle any remaining bytes of data. */
207
208 memcpy(ctx->in, buf, len);
209 }
210
211
212 /*
213 * Final wrapup - pad to 64-byte boundary with the bit pattern
214 * 1 0* (64-bit count of bits processed, MSB-first)
215 */
MD5Final(struct MD5Context * ctx,unsigned char * digest)216 static void MD5Final(struct MD5Context *ctx, unsigned char *digest)
217 {
218 unsigned count;
219 unsigned char *p;
220
221 /* Compute number of bytes mod 64 */
222 count = (ctx->bits[0] >> 3) & 0x3F;
223
224 /* Set the first char of padding to 0x80. This is safe since there is
225 always at least one byte free */
226 p = ctx->in + count;
227 *p++ = 0x80;
228
229 /* Bytes of padding needed to make 64 bytes */
230 count = 64 - 1 - count;
231
232 /* Pad out to 56 mod 64 */
233 if (count < 8) {
234 /* Two lots of padding: Pad the first block to 64 bytes */
235 memset(p, 0, count);
236 byteReverse(ctx->in, 16);
237 MD5Transform(ctx->buf, (uint32_t *) ctx->in);
238
239 /* Now fill the next block with 56 bytes */
240 memset(ctx->in, 0, 56);
241 } else {
242 /* Pad block to 56 bytes */
243 memset(p, 0, count - 8);
244 }
245 byteReverse(ctx->in, 14);
246
247 /* Append length in bits and transform */
248 ((uint32_t *) ctx->in)[14] = ctx->bits[0];
249 ((uint32_t *) ctx->in)[15] = ctx->bits[1];
250
251 MD5Transform(ctx->buf, (uint32_t *) ctx->in);
252 byteReverse((unsigned char *) ctx->buf, 4);
253
254 if (digest!=NULL)
255 memcpy(digest, ctx->buf, 16);
256 memset(ctx, 0, sizeof(ctx)); /* In case it's sensitive */
257 }
258
259
Com_MD5File(const char * fn,int length,const char * prefix,int prefix_len)260 char *Com_MD5File( const char *fn, int length, const char *prefix, int prefix_len )
261 {
262 static char final[33] = {""};
263 unsigned char digest[16] = {""};
264 fileHandle_t f;
265 MD5_CTX md5;
266 byte buffer[2048];
267 int i;
268 int filelen = 0;
269 int r = 0;
270 int total = 0;
271
272 Q_strncpyz( final, "", sizeof( final ) );
273
274 filelen = FS_SV_FOpenFileRead( fn, &f );
275
276 if( !f ) {
277 return final;
278 }
279 if( filelen < 1 ) {
280 FS_FCloseFile( f );
281 return final;
282 }
283 if(filelen < length || !length) {
284 length = filelen;
285 }
286
287 MD5Init(&md5);
288
289 if( prefix_len && *prefix )
290 MD5Update(&md5 , (unsigned char *)prefix, prefix_len);
291
292 for(;;) {
293 r = FS_Read2(buffer, sizeof(buffer), f);
294 if(r < 1)
295 break;
296 if(r + total > length)
297 r = length - total;
298 total += r;
299 MD5Update(&md5 , buffer, r);
300 if(r < sizeof(buffer) || total >= length)
301 break;
302 }
303 FS_FCloseFile(f);
304 MD5Final(&md5, digest);
305 final[0] = '\0';
306 for(i = 0; i < 16; i++) {
307 Q_strcat(final, sizeof(final), va("%02X", digest[i]));
308 }
309 return final;
310 }
311