GNU libmicrohttpd
0.9.5
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00001 /* 00002 * This code implements the MD5 message-digest algorithm. 00003 * The algorithm is due to Ron Rivest. This code was 00004 * written by Colin Plumb in 1993, no copyright is claimed. 00005 * This code is in the public domain; do with it what you wish. 00006 * 00007 * Equivalent code is available from RSA Data Security, Inc. 00008 * This code has been tested against that, and is equivalent, 00009 * except that you don't need to include two pages of legalese 00010 * with every copy. 00011 * 00012 * To compute the message digest of a chunk of bytes, declare an 00013 * MD5Context structure, pass it to MD5Init, call MD5Update as 00014 * needed on buffers full of bytes, and then call MD5Final, which 00015 * will fill a supplied 16-byte array with the digest. 00016 */ 00017 00018 /* Brutally hacked by John Walker back from ANSI C to K&R (no 00019 prototypes) to maintain the tradition that Netfone will compile 00020 with Sun's original "cc". */ 00021 00022 #include <memory.h> 00023 #include <stdint.h> 00024 #include "md5.h" 00025 00026 #ifndef HIGHFIRST 00027 #define byteReverse(buf, len) /* Nothing */ 00028 #else 00029 /* 00030 * Note: this code is harmless on little-endian machines. 00031 */ 00032 static void 00033 byteReverse(unsigned char *buf, 00034 unsigned longs) 00035 { 00036 uint32_t t; 00037 do { 00038 t = (uint32_t) ((unsigned) buf[3] << 8 | buf[2]) << 16 | 00039 ((unsigned) buf[1] << 8 | buf[0]); 00040 *(uint32_t *) buf = t; 00041 buf += 4; 00042 } while (--longs); 00043 } 00044 #endif 00045 00046 00047 /* The four core functions - F1 is optimized somewhat */ 00048 00049 /* #define F1(x, y, z) (x & y | ~x & z) */ 00050 #define F1(x, y, z) (z ^ (x & (y ^ z))) 00051 #define F2(x, y, z) F1(z, x, y) 00052 #define F3(x, y, z) (x ^ y ^ z) 00053 #define F4(x, y, z) (y ^ (x | ~z)) 00054 00055 /* This is the central step in the MD5 algorithm. */ 00056 #define MD5STEP(f, w, x, y, z, data, s) \ 00057 ( w += f(x, y, z) + data, w = w<<s | w>>(32-s), w += x ) 00058 00059 /* 00060 * The core of the MD5 algorithm, this alters an existing MD5 hash to 00061 * reflect the addition of 16 longwords of new data. MD5Update blocks 00062 * the data and converts bytes into longwords for this routine. 00063 */ 00064 static void 00065 MD5Transform(uint32_t buf[4], 00066 uint32_t in[16]) 00067 { 00068 uint32_t a, b, c, d; 00069 00070 a = buf[0]; 00071 b = buf[1]; 00072 c = buf[2]; 00073 d = buf[3]; 00074 00075 MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7); 00076 MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12); 00077 MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17); 00078 MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22); 00079 MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7); 00080 MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12); 00081 MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17); 00082 MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22); 00083 MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7); 00084 MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12); 00085 MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17); 00086 MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22); 00087 MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7); 00088 MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12); 00089 MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17); 00090 MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22); 00091 00092 MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5); 00093 MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9); 00094 MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14); 00095 MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20); 00096 MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5); 00097 MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9); 00098 MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14); 00099 MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20); 00100 MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5); 00101 MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9); 00102 MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14); 00103 MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20); 00104 MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5); 00105 MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9); 00106 MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14); 00107 MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20); 00108 00109 MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4); 00110 MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11); 00111 MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16); 00112 MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23); 00113 MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4); 00114 MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11); 00115 MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16); 00116 MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23); 00117 MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4); 00118 MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11); 00119 MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16); 00120 MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23); 00121 MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4); 00122 MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11); 00123 MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16); 00124 MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23); 00125 00126 MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6); 00127 MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10); 00128 MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15); 00129 MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21); 00130 MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6); 00131 MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10); 00132 MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15); 00133 MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21); 00134 MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6); 00135 MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10); 00136 MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15); 00137 MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21); 00138 MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6); 00139 MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10); 00140 MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15); 00141 MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21); 00142 00143 buf[0] += a; 00144 buf[1] += b; 00145 buf[2] += c; 00146 buf[3] += d; 00147 } 00148 00149 00150 /* 00151 * Start MD5 accumulation. Set bit count to 0 and buffer to mysterious 00152 * initialization constants. 00153 */ 00154 void MD5Init(struct MD5Context *ctx) 00155 { 00156 ctx->buf[0] = 0x67452301; 00157 ctx->buf[1] = 0xefcdab89; 00158 ctx->buf[2] = 0x98badcfe; 00159 ctx->buf[3] = 0x10325476; 00160 00161 ctx->bits[0] = 0; 00162 ctx->bits[1] = 0; 00163 } 00164 00165 /* 00166 * Update context to reflect the concatenation of another buffer full 00167 * of bytes. 00168 */ 00169 void 00170 MD5Update(struct MD5Context *ctx, 00171 const void *data, 00172 unsigned len) 00173 { 00174 const unsigned char *buf = data; 00175 uint32_t t; 00176 00177 /* Update bitcount */ 00178 00179 t = ctx->bits[0]; 00180 if ((ctx->bits[0] = t + ((uint32_t) len << 3)) < t) 00181 ctx->bits[1]++; /* Carry from low to high */ 00182 ctx->bits[1] += len >> 29; 00183 00184 t = (t >> 3) & 0x3f; /* Bytes already in shsInfo->data */ 00185 00186 /* Handle any leading odd-sized chunks */ 00187 00188 if (t) { 00189 unsigned char *p = (unsigned char *) ctx->in + t; 00190 00191 t = 64 - t; 00192 if (len < t) { 00193 memcpy(p, buf, len); 00194 return; 00195 } 00196 memcpy(p, buf, t); 00197 byteReverse(ctx->in, 16); 00198 MD5Transform(ctx->buf, (uint32_t *) ctx->in); 00199 buf += t; 00200 len -= t; 00201 } 00202 /* Process data in 64-byte chunks */ 00203 00204 while (len >= 64) { 00205 memcpy(ctx->in, buf, 64); 00206 byteReverse(ctx->in, 16); 00207 MD5Transform(ctx->buf, (uint32_t *) ctx->in); 00208 buf += 64; 00209 len -= 64; 00210 } 00211 00212 /* Handle any remaining bytes of data. */ 00213 00214 memcpy(ctx->in, buf, len); 00215 } 00216 00217 /* 00218 * Final wrapup - pad to 64-byte boundary with the bit pattern 00219 * 1 0* (64-bit count of bits processed, MSB-first) 00220 */ 00221 void MD5Final(unsigned char digest[16], 00222 struct MD5Context *ctx) 00223 { 00224 unsigned count; 00225 unsigned char *p; 00226 00227 /* Compute number of bytes mod 64 */ 00228 count = (ctx->bits[0] >> 3) & 0x3F; 00229 00230 /* Set the first char of padding to 0x80. This is safe since there is 00231 always at least one byte free */ 00232 p = ctx->in + count; 00233 *p++ = 0x80; 00234 00235 /* Bytes of padding needed to make 64 bytes */ 00236 count = 64 - 1 - count; 00237 00238 /* Pad out to 56 mod 64 */ 00239 if (count < 8) { 00240 /* Two lots of padding: Pad the first block to 64 bytes */ 00241 memset(p, 0, count); 00242 byteReverse(ctx->in, 16); 00243 MD5Transform(ctx->buf, (uint32_t *) ctx->in); 00244 00245 /* Now fill the next block with 56 bytes */ 00246 memset(ctx->in, 0, 56); 00247 } else { 00248 /* Pad block to 56 bytes */ 00249 memset(p, 0, count - 8); 00250 } 00251 byteReverse(ctx->in, 14); 00252 00253 /* Append length in bits and transform */ 00254 ((uint32_t *) ctx->in)[14] = ctx->bits[0]; 00255 ((uint32_t *) ctx->in)[15] = ctx->bits[1]; 00256 00257 MD5Transform(ctx->buf, (uint32_t *) ctx->in); 00258 byteReverse((unsigned char *) ctx->buf, 4); 00259 memcpy(digest, ctx->buf, 16); 00260 memset(ctx, 0, sizeof(struct MD5Context)); /* In case it's sensitive */ 00261 } 00262 00263 /* end of md5.c */