/************************************************************************ * IRC - Internet Relay Chat, ircd/random.c * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 1, or (at your option) * any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include #include #include #include #include "config.h" char localkey[8] = RANDOM_SEED; /* * MD5 transform algorithm, taken from code written by Colin Plumb, * and put into the public domain * * Kev: Taken from Ted T'so's /dev/random random.c code and modified to * be slightly simpler. That code is released under a BSD-style copyright * OR under the terms of the GNU Public License, which should be included * at the top of this source file. * * record: Cleaned up to work with ircd. RANDOM_TOKEN is defined in * setup.h by the make script; if people start to "guess" your cookies, * consider recompiling your server with a different random token. */ /* The four core functions - F1 is optimized somewhat */ #define F1(x, y, z) (z ^ (x & (y ^ z))) #define F2(x, y, z) F1(z, x, y) #define F3(x, y, z) (x ^ y ^ z) #define F4(x, y, z) (y ^ (x | ~z)) /* This is the central step in the MD5 algorithm. */ #define MD5STEP(f, w, x, y, z, data, s) \ ( w += f(x, y, z) + data, w = w<>(32-s), w += x ) /* * The core of the MD5 algorithm, this alters an existing MD5 hash to * reflect the addition of 16 longwords of new data. MD5Update blocks * the data and converts bytes into longwords for this routine. * * original comment left in; this used to be called MD5Transform and took * two arguments; I've internalized those arguments, creating the character * array "localkey," which should contain 8 bytes of data. The function also * originally returned nothing; now it returns an unsigned long that is the * random number. It appears to be reallyrandom, so... -Kev * * I don't really know what this does. I tried to figure it out and got * a headache. If you know what's good for you, you'll leave this stuff * for the smart people and do something else. -record */ unsigned long ircrandom(void) { unsigned long a, b, c, d; unsigned char in[16]; struct timeval tv; (void)gettimeofday(&tv, NULL); (void)memcpy((void *)in, (void *)localkey, 8); (void)memcpy((void *)(in+8), (void *)&tv.tv_sec, 4); (void)memcpy((void *)(in+12), (void *)&tv.tv_usec, 4); a = 0x67452301; b = 0xefcdab89; c = 0x98badcfe; d = 0x10325476; MD5STEP(F1, a, b, c, d, (long)in[ 0]+0xd76aa478, 7); MD5STEP(F1, d, a, b, c, (long)in[ 1]+0xe8c7b756, 12); MD5STEP(F1, c, d, a, b, (long)in[ 2]+0x242070db, 17); MD5STEP(F1, b, c, d, a, (long)in[ 3]+0xc1bdceee, 22); MD5STEP(F1, a, b, c, d, (long)in[ 4]+0xf57c0faf, 7); MD5STEP(F1, d, a, b, c, (long)in[ 5]+0x4787c62a, 12); MD5STEP(F1, c, d, a, b, (long)in[ 6]+0xa8304613, 17); MD5STEP(F1, b, c, d, a, (long)in[ 7]+0xfd469501, 22); MD5STEP(F1, a, b, c, d, (long)in[ 8]+0x698098d8, 7); MD5STEP(F1, d, a, b, c, (long)in[ 9]+0x8b44f7af, 12); MD5STEP(F1, c, d, a, b, (long)in[10]+0xffff5bb1, 17); MD5STEP(F1, b, c, d, a, (long)in[11]+0x895cd7be, 22); MD5STEP(F1, a, b, c, d, (long)in[12]+0x6b901122, 7); MD5STEP(F1, d, a, b, c, (long)in[13]+0xfd987193, 12); MD5STEP(F1, c, d, a, b, (long)in[14]+0xa679438e, 17); MD5STEP(F1, b, c, d, a, (long)in[15]+0x49b40821, 22); MD5STEP(F2, a, b, c, d, (long)in[ 1]+0xf61e2562, 5); MD5STEP(F2, d, a, b, c, (long)in[ 6]+0xc040b340, 9); MD5STEP(F2, c, d, a, b, (long)in[11]+0x265e5a51, 14); MD5STEP(F2, b, c, d, a, (long)in[ 0]+0xe9b6c7aa, 20); MD5STEP(F2, a, b, c, d, (long)in[ 5]+0xd62f105d, 5); MD5STEP(F2, d, a, b, c, (long)in[10]+0x02441453, 9); MD5STEP(F2, c, d, a, b, (long)in[15]+0xd8a1e681, 14); MD5STEP(F2, b, c, d, a, (long)in[ 4]+0xe7d3fbc8, 20); MD5STEP(F2, a, b, c, d, (long)in[ 9]+0x21e1cde6, 5); MD5STEP(F2, d, a, b, c, (long)in[14]+0xc33707d6, 9); MD5STEP(F2, c, d, a, b, (long)in[ 3]+0xf4d50d87, 14); MD5STEP(F2, b, c, d, a, (long)in[ 8]+0x455a14ed, 20); MD5STEP(F2, a, b, c, d, (long)in[13]+0xa9e3e905, 5); MD5STEP(F2, d, a, b, c, (long)in[ 2]+0xfcefa3f8, 9); MD5STEP(F2, c, d, a, b, (long)in[ 7]+0x676f02d9, 14); MD5STEP(F2, b, c, d, a, (long)in[12]+0x8d2a4c8a, 20); MD5STEP(F3, a, b, c, d, (long)in[ 5]+0xfffa3942, 4); MD5STEP(F3, d, a, b, c, (long)in[ 8]+0x8771f681, 11); MD5STEP(F3, c, d, a, b, (long)in[11]+0x6d9d6122, 16); MD5STEP(F3, b, c, d, a, (long)in[14]+0xfde5380c, 23); MD5STEP(F3, a, b, c, d, (long)in[ 1]+0xa4beea44, 4); MD5STEP(F3, d, a, b, c, (long)in[ 4]+0x4bdecfa9, 11); MD5STEP(F3, c, d, a, b, (long)in[ 7]+0xf6bb4b60, 16); MD5STEP(F3, b, c, d, a, (long)in[10]+0xbebfbc70, 23); MD5STEP(F3, a, b, c, d, (long)in[13]+0x289b7ec6, 4); MD5STEP(F3, d, a, b, c, (long)in[ 0]+0xeaa127fa, 11); MD5STEP(F3, c, d, a, b, (long)in[ 3]+0xd4ef3085, 16); MD5STEP(F3, b, c, d, a, (long)in[ 6]+0x04881d05, 23); MD5STEP(F3, a, b, c, d, (long)in[ 9]+0xd9d4d039, 4); MD5STEP(F3, d, a, b, c, (long)in[12]+0xe6db99e5, 11); MD5STEP(F3, c, d, a, b, (long)in[15]+0x1fa27cf8, 16); MD5STEP(F3, b, c, d, a, (long)in[ 2]+0xc4ac5665, 23); MD5STEP(F4, a, b, c, d, (long)in[ 0]+0xf4292244, 6); MD5STEP(F4, d, a, b, c, (long)in[ 7]+0x432aff97, 10); MD5STEP(F4, c, d, a, b, (long)in[14]+0xab9423a7, 15); MD5STEP(F4, b, c, d, a, (long)in[ 5]+0xfc93a039, 21); MD5STEP(F4, a, b, c, d, (long)in[12]+0x655b59c3, 6); MD5STEP(F4, d, a, b, c, (long)in[ 3]+0x8f0ccc92, 10); MD5STEP(F4, c, d, a, b, (long)in[10]+0xffeff47d, 15); MD5STEP(F4, b, c, d, a, (long)in[ 1]+0x85845dd1, 21); MD5STEP(F4, a, b, c, d, (long)in[ 8]+0x6fa87e4f, 6); MD5STEP(F4, d, a, b, c, (long)in[15]+0xfe2ce6e0, 10); MD5STEP(F4, c, d, a, b, (long)in[ 6]+0xa3014314, 15); MD5STEP(F4, b, c, d, a, (long)in[13]+0x4e0811a1, 21); MD5STEP(F4, a, b, c, d, (long)in[ 4]+0xf7537e82, 6); MD5STEP(F4, d, a, b, c, (long)in[11]+0xbd3af235, 10); MD5STEP(F4, c, d, a, b, (long)in[ 2]+0x2ad7d2bb, 15); MD5STEP(F4, b, c, d, a, (long)in[ 9]+0xeb86d391, 21); /* * we have 4 unsigned longs generated by the above sequence; this scrambles * them together so that if there is any pattern, it will be obscured. */ return (a ^ b ^ c ^ d); }