stun/rand.c

   1 /*
   2  * This file is part of the Nice GLib ICE library.
   3  *
   4  * (C) 2008 Nokia Corporation. All rights reserved.
   5  * (C) 2008 Collabora Ltd. All rights reserved.
   6  *  Contact: Youness Alaoui
   7  *
   8  * The contents of this file are subject to the Mozilla Public License Version
   9  * 1.1 (the "License"); you may not use this file except in compliance with
  10  * the License. You may obtain a copy of the License at
  11  * http://www.mozilla.org/MPL/
  12  *
  13  * Software distributed under the License is distributed on an "AS IS" basis,
  14  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  15  * for the specific language governing rights and limitations under the
  16  * License.
  17  *
  18  * The Original Code is the Nice GLib ICE library.
  19  *
  20  * The Initial Developers of the Original Code are Collabora Ltd and Nokia
  21  * Corporation. All Rights Reserved.
  22  *
  23  * Alternatively, the contents of this file may be used under the terms of the
  24  * the GNU Lesser General Public License Version 2.1 (the "LGPL"), in which
  25  * case the provisions of LGPL are applicable instead of those above. If you
  26  * wish to allow use of your version of this file only under the terms of the
  27  * LGPL and not to allow others to use your version of this file under the
  28  * MPL, indicate your decision by deleting the provisions above and replace
  29  * them with the notice and other provisions required by the LGPL. If you do
  30  * not delete the provisions above, a recipient may use your version of this
  31  * file under either the MPL or the LGPL.
  32  */
  33
  34
  35
  36 #ifdef HAVE_CONFIG_H
  37 # include <config.h>
  38 #endif
  39
  40 #include "rand.h"
  41
  42
  43 #ifdef _WIN32
  44
  45 #include <windows.h>
  46
  47 void RAND_bytes (uint8_t *dst, int len)
  48 {
  49   HCRYPTPROV hCryptProv;
  50   LPCSTR container = "Libnice key container";
  51
  52   if(!CryptAcquireContext(&hCryptProv, container, NULL, PROV_RSA_FULL, 0)) {
  53     /* non existing container. try to create a new one */
  54     if (GetLastError() == NTE_BAD_KEYSET) {
  55       if(!CryptAcquireContext(&hCryptProv, container, NULL, PROV_RSA_FULL, CRYPT_NEWKEYSET)) {
  56         return;
  57       }
  58     }
  59     return;
  60   }
  61
  62   CryptGenRandom (hCryptProv, len, dst);
  63
  64   CryptReleaseContext(hCryptProv,0);
  65 }
  66 #else
  67
  68 /* ------------- Start original implementation. ----------------- */
  69 /* http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/MT2002/emt19937ar.html */
  70
  71 /*
  72    A C-program for MT19937, with initialization improved 2002/1/26.
  73    Coded by Takuji Nishimura and Makoto Matsumoto.
  74
  75    Before using, initialize the state by using init_genrand(seed)
  76    or init_by_array(init_key, key_length).
  77
  78    Copyright (C) 1997 - 2002, Makoto Matsumoto and Takuji Nishimura,
  79    All rights reserved
  80
  81    Redistribution and use in source and binary forms, with or without
  82    modification, are permitted provided that the following conditions
  83    are met:
  84
  85      1. Redistributions of source code must retain the above copyright
  86         notice, this list of conditions and the following disclaimer.
  87
  88      2. Redistributions in binary form must reproduce the above copyright
  89         notice, this list of conditions and the following disclaimer in the
  90         documentation and/or other materials provided with the distribution.
  91
  92      3. The names of its contributors may not be used to endorse or promote
  93         products derived from this software without specific prior written
  94         permission.
  95
  96    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  97    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  98    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  99    A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 100    CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 101    EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 102    PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 103    PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 104    LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 105    NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 106    SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 107
 108
 109    Any feedback is very welcome.
 110    http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/emt.html
 111    email: m-mat @ math.sci.hiroshima-u.ac.jp (remove space)
 112 */
 113
 114 /* Period parameters */
 115 #define N 624
 116 #define M 397
 117 #define MATRIX_A 0x9908b0dfUL   /* constant vector a */
 118 #define UPPER_MASK 0x80000000UL /* most significant w-r bits */
 119 #define LOWER_MASK 0x7fffffffUL /* least significant r bits */
 120
 121 static unsigned long mt[N]; /* the array for the state vector  */
 122 static int mti=N+1; /* mti==N+1 means mt[N] is not initialized */
 123
 124 /* initializes mt[N] with a seed */
 125 static void init_genrand(unsigned long s)
 126 {
 127   mt[0]= s & 0xffffffffUL;
 128   for (mti=1; mti<N; mti++) {
 129     mt[mti] = (1812433253UL * (mt[mti-1] ^ (mt[mti-1] >> 30)) + mti);
 130     /* See Knuth TAOCP Vol2. 3rd Ed. P.106 for multiplier. */
 131     /* In the previous versions, MSBs of the seed affect   */
 132     /* only MSBs of the array mt[].                        */
 133     /* 2002/01/09 modified by Makoto Matsumoto             */
 134     mt[mti] &= 0xffffffffUL;
 135     /* for >32 bit machines */
 136   }
 137 }
 138
 139 /* initialize by an array with array-length */
 140 /* init_key is the array for initializing keys */
 141 /* key_length is its length */
 142 /* slight change for C++, 2004/2/26 */
 143 static void init_by_array(unsigned long init_key[], int key_length)
 144 {
 145   int i, j, k;
 146   init_genrand(19650218UL);
 147   i=1; j=0;
 148   k = (N>key_length ? N : key_length);
 149   for (; k; k--) {
 150     mt[i] = (mt[i] ^ ((mt[i-1] ^ (mt[i-1] >> 30)) * 1664525UL))
 151         + init_key[j] + j; /* non linear */
 152     mt[i] &= 0xffffffffUL; /* for WORDSIZE > 32 machines */
 153     i++; j++;
 154     if (i>=N) { mt[0] = mt[N-1]; i=1; }
 155     if (j>=key_length) j=0;
 156   }
 157   for (k=N-1; k; k--) {
 158     mt[i] = (mt[i] ^ ((mt[i-1] ^ (mt[i-1] >> 30)) * 1566083941UL))
 159         - i; /* non linear */
 160     mt[i] &= 0xffffffffUL; /* for WORDSIZE > 32 machines */
 161     i++;
 162     if (i>=N) { mt[0] = mt[N-1]; i=1; }
 163   }
 164
 165   mt[0] = 0x80000000UL; /* MSB is 1; assuring non-zero initial array */
 166 }
 167
 168 /* generates a random number on [0,0xffffffff]-interval */
 169 static unsigned long genrand_int32(void)
 170 {
 171   unsigned long y;
 172   static unsigned long mag01[2]={0x0UL, MATRIX_A};
 173   /* mag01[x] = x * MATRIX_A  for x=0,1 */
 174
 175   if (mti >= N) { /* generate N words at one time */
 176     int kk;
 177
 178     if (mti == N+1)   /* if init_genrand() has not been called, */
 179       init_genrand(5489UL); /* a default initial seed is used */
 180
 181     for (kk=0;kk<N-M;kk++) {
 182       y = (mt[kk]&UPPER_MASK)|(mt[kk+1]&LOWER_MASK);
 183       mt[kk] = mt[kk+M] ^ (y >> 1) ^ mag01[y & 0x1UL];
 184     }
 185     for (;kk<N-1;kk++) {
 186       y = (mt[kk]&UPPER_MASK)|(mt[kk+1]&LOWER_MASK);
 187       mt[kk] = mt[kk+(M-N)] ^ (y >> 1) ^ mag01[y & 0x1UL];
 188     }
 189     y = (mt[N-1]&UPPER_MASK)|(mt[0]&LOWER_MASK);
 190     mt[N-1] = mt[M-1] ^ (y >> 1) ^ mag01[y & 0x1UL];
 191
 192     mti = 0;
 193   }
 194
 195   y = mt[mti++];
 196
 197   /* Tempering */
 198   y ^= (y >> 11);
 199   y ^= (y << 7) & 0x9d2c5680UL;
 200   y ^= (y << 15) & 0xefc60000UL;
 201   y ^= (y >> 18);
 202
 203   return y;
 204 }
 205
 206 /* These real versions are due to Isaku Wada, 2002/01/09 added */
 207
 208 /* ------------- End original implementation. ----------------- */
 209
 210 #include <stdio.h>
 211 #include <time.h>
 212
 213 static int initialized = 0;
 214
 215 void RAND_bytes (uint8_t *dst, int len)
 216 {
 217   int i;
 218
 219   if (!initialized) {
 220     /* Seed the generator with an array from /dev/urandom if available
 221        Otherwise use time() and clock() values */
 222
 223     FILE *urandom = fopen( "/dev/urandom", "rb" );
 224     unsigned long init_key[10] = {};
 225     int key_length = 0;
 226     if (urandom) {
 227       while (fread(&init_key[key_length++], sizeof(unsigned long), 1,
 228               urandom) > 0 &&    key_length < 10);
 229       fclose(urandom);
 230     } else {
 231       time_t t = time (NULL);
 232       clock_t c = clock ();
 233       init_key[0] = *((unsigned long *) dst);
 234       init_key[1] = 0x6c69626e;
 235       init_key[2] = 0x69636500;
 236       init_key[3] = *(unsigned long *) &t;
 237       init_key[4] = *(unsigned long *) &c;
 238       key_length = 5;
 239     }
 240     init_by_array(init_key, key_length);
 241     initialized = 1;
 242   }
 243
 244   for (i = 0; i < len; i++) {
 245     dst[i] = genrand_int32 () & 0xFF;
 246   }
 247 }
 248
 249 #endif /* _WIN32 */