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.
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
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.
17 * Changed so as no longer to depend on Colin Plumb's `usual.h' header
18 * definitions; now uses stuff from dpkg's config.h.
19 * - Ian Jackson <ijackson@nyx.cs.du.edu>.
20 * Still in the public domain.
22 * Josh Coalson: made some changes to integrate with libFLAC.
23 * Still in the public domain.
26 #include <stdlib.h> /* for malloc() */
27 #include <string.h> /* for memcpy() */
29 #include "private/md5.h"
31 static bool is_big_endian_host_;
34 byteSwap(uint32 *buf, unsigned words)
36 md5byte *p = (md5byte *)buf;
38 if(!is_big_endian_host_)
41 *buf++ = (uint32)((unsigned)p[3] << 8 | p[2]) << 16 | ((unsigned)p[1] << 8 | p[0]);
47 * Start MD5 accumulation. Set bit count to 0 and buffer to mysterious
48 * initialization constants.
51 MD5Init(struct MD5Context *ctx)
55 is_big_endian_host_ = (*((byte*)(&test)))? false : true;
57 ctx->buf[0] = 0x67452301;
58 ctx->buf[1] = 0xefcdab89;
59 ctx->buf[2] = 0x98badcfe;
60 ctx->buf[3] = 0x10325476;
65 ctx->internal_buf = 0;
70 * Update context to reflect the concatenation of another buffer full
74 MD5Update(struct MD5Context *ctx, md5byte const *buf, unsigned len)
78 /* Update byte count */
81 if ((ctx->bytes[0] = t + len) < t)
82 ctx->bytes[1]++; /* Carry from low to high */
84 t = 64 - (t & 0x3f); /* Space available in ctx->in (at least 1) */
86 memcpy((md5byte *)ctx->in + 64 - t, buf, len);
89 /* First chunk is an odd size */
90 memcpy((md5byte *)ctx->in + 64 - t, buf, t);
91 byteSwap(ctx->in, 16);
92 MD5Transform(ctx->buf, ctx->in);
96 /* Process data in 64-byte chunks */
98 memcpy(ctx->in, buf, 64);
99 byteSwap(ctx->in, 16);
100 MD5Transform(ctx->buf, ctx->in);
105 /* Handle any remaining bytes of data. */
106 memcpy(ctx->in, buf, len);
110 * Convert the incoming audio signal to a byte stream and MD5Update it.
113 FLAC__MD5Accumulate(struct MD5Context *ctx, const int32 *signal[], unsigned channels, unsigned samples, unsigned bytes_per_sample)
115 unsigned channel, sample, a_byte;
118 const unsigned bytes_needed = channels * samples * bytes_per_sample;
120 if(ctx->capacity < bytes_needed) {
121 byte *tmp = realloc(ctx->internal_buf, bytes_needed);
123 free(ctx->internal_buf);
124 if(0 == (ctx->internal_buf = malloc(bytes_needed)))
127 ctx->internal_buf = tmp;
128 ctx->capacity = bytes_needed;
131 buf_ = ctx->internal_buf;
133 for(sample = 0; sample < samples; sample++) {
134 for(channel = 0; channel < channels; channel++) {
135 a_word = signal[channel][sample];
136 for(a_byte = 0; a_byte < bytes_per_sample; a_byte++) {
137 *buf_++ = (byte)(a_word & 0xff);
143 MD5Update(ctx, ctx->internal_buf, bytes_needed);
149 * Final wrapup - pad to 64-byte boundary with the bit pattern
150 * 1 0* (64-bit count of bits processed, MSB-first)
153 MD5Final(md5byte digest[16], struct MD5Context *ctx)
155 int count = ctx->bytes[0] & 0x3f; /* Number of bytes in ctx->in */
156 md5byte *p = (md5byte *)ctx->in + count;
158 /* Set the first char of padding to 0x80. There is always room. */
161 /* Bytes of padding needed to make 56 bytes (-8..55) */
162 count = 56 - 1 - count;
164 if (count < 0) { /* Padding forces an extra block */
165 memset(p, 0, count + 8);
166 byteSwap(ctx->in, 16);
167 MD5Transform(ctx->buf, ctx->in);
168 p = (md5byte *)ctx->in;
172 byteSwap(ctx->in, 14);
174 /* Append length in bits and transform */
175 ctx->in[14] = ctx->bytes[0] << 3;
176 ctx->in[15] = ctx->bytes[1] << 3 | ctx->bytes[0] >> 29;
177 MD5Transform(ctx->buf, ctx->in);
179 byteSwap(ctx->buf, 4);
180 memcpy(digest, ctx->buf, 16);
181 memset(ctx, 0, sizeof(ctx)); /* In case it's sensitive */
182 if(0 != ctx->internal_buf) {
183 free(ctx->internal_buf);
184 ctx->internal_buf = 0;
191 /* The four core functions - F1 is optimized somewhat */
193 /* #define F1(x, y, z) (x & y | ~x & z) */
194 #define F1(x, y, z) (z ^ (x & (y ^ z)))
195 #define F2(x, y, z) F1(z, x, y)
196 #define F3(x, y, z) (x ^ y ^ z)
197 #define F4(x, y, z) (y ^ (x | ~z))
199 /* This is the central step in the MD5 algorithm. */
200 #define MD5STEP(f,w,x,y,z,in,s) \
201 (w += f(x,y,z) + in, w = (w<<s | w>>(32-s)) + x)
204 * The core of the MD5 algorithm, this alters an existing MD5 hash to
205 * reflect the addition of 16 longwords of new data. MD5Update blocks
206 * the data and converts bytes into longwords for this routine.
209 MD5Transform(uint32 buf[4], uint32 const in[16])
211 register uint32 a, b, c, d;
218 MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
219 MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
220 MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
221 MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
222 MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
223 MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
224 MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
225 MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
226 MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
227 MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
228 MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
229 MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
230 MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
231 MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
232 MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
233 MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
235 MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
236 MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
237 MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
238 MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
239 MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
240 MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
241 MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
242 MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
243 MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
244 MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
245 MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
246 MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
247 MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
248 MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
249 MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
250 MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
252 MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
253 MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
254 MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
255 MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
256 MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
257 MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
258 MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
259 MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
260 MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
261 MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
262 MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
263 MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
264 MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
265 MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
266 MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
267 MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
269 MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
270 MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
271 MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
272 MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
273 MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
274 MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
275 MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
276 MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
277 MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
278 MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
279 MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
280 MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
281 MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
282 MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
283 MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
284 MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);