crypto/openssl/crypto/rand/rand_unix.c

   1 /* crypto/rand/rand_unix.c */
   2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
   3  * All rights reserved.
   4  *
   5  * This package is an SSL implementation written
   6  * by Eric Young (eay@cryptsoft.com).
   7  * The implementation was written so as to conform with Netscapes SSL.
   8  *
   9  * This library is free for commercial and non-commercial use as long as
  10  * the following conditions are aheared to.  The following conditions
  11  * apply to all code found in this distribution, be it the RC4, RSA,
  12  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
  13  * included with this distribution is covered by the same copyright terms
  14  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
  15  *
  16  * Copyright remains Eric Young's, and as such any Copyright notices in
  17  * the code are not to be removed.
  18  * If this package is used in a product, Eric Young should be given attribution
  19  * as the author of the parts of the library used.
  20  * This can be in the form of a textual message at program startup or
  21  * in documentation (online or textual) provided with the package.
  22  *
  23  * Redistribution and use in source and binary forms, with or without
  24  * modification, are permitted provided that the following conditions
  25  * are met:
  26  * 1. Redistributions of source code must retain the copyright
  27  *    notice, this list of conditions and the following disclaimer.
  28  * 2. Redistributions in binary form must reproduce the above copyright
  29  *    notice, this list of conditions and the following disclaimer in the
  30  *    documentation and/or other materials provided with the distribution.
  31  * 3. All advertising materials mentioning features or use of this software
  32  *    must display the following acknowledgement:
  33  *    "This product includes cryptographic software written by
  34  *     Eric Young (eay@cryptsoft.com)"
  35  *    The word 'cryptographic' can be left out if the rouines from the library
  36  *    being used are not cryptographic related :-).
  37  * 4. If you include any Windows specific code (or a derivative thereof) from
  38  *    the apps directory (application code) you must include an acknowledgement:
  39  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
  40  *
  41  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
  42  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  43  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  44  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  45  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  46  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  47  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  49  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  50  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  51  * SUCH DAMAGE.
  52  *
  53  * The licence and distribution terms for any publically available version or
  54  * derivative of this code cannot be changed.  i.e. this code cannot simply be
  55  * copied and put under another distribution licence
  56  * [including the GNU Public Licence.]
  57  */
  58 /* ====================================================================
  59  * Copyright (c) 1998-2006 The OpenSSL Project.  All rights reserved.
  60  *
  61  * Redistribution and use in source and binary forms, with or without
  62  * modification, are permitted provided that the following conditions
  63  * are met:
  64  *
  65  * 1. Redistributions of source code must retain the above copyright
  66  *    notice, this list of conditions and the following disclaimer.
  67  *
  68  * 2. Redistributions in binary form must reproduce the above copyright
  69  *    notice, this list of conditions and the following disclaimer in
  70  *    the documentation and/or other materials provided with the
  71  *    distribution.
  72  *
  73  * 3. All advertising materials mentioning features or use of this
  74  *    software must display the following acknowledgment:
  75  *    "This product includes software developed by the OpenSSL Project
  76  *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
  77  *
  78  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
  79  *    endorse or promote products derived from this software without
  80  *    prior written permission. For written permission, please contact
  81  *    openssl-core@openssl.org.
  82  *
  83  * 5. Products derived from this software may not be called "OpenSSL"
  84  *    nor may "OpenSSL" appear in their names without prior written
  85  *    permission of the OpenSSL Project.
  86  *
  87  * 6. Redistributions of any form whatsoever must retain the following
  88  *    acknowledgment:
  89  *    "This product includes software developed by the OpenSSL Project
  90  *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
  91  *
  92  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
  93  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  94  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  95  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
  96  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  97  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  98  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  99  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 100  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 101  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 102  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 103  * OF THE POSSIBILITY OF SUCH DAMAGE.
 104  * ====================================================================
 105  *
 106  * This product includes cryptographic software written by Eric Young
 107  * (eay@cryptsoft.com).  This product includes software written by Tim
 108  * Hudson (tjh@cryptsoft.com).
 109  *
 110  */
 111 #include <stdio.h>
 112
 113 #define USE_SOCKETS
 114 #include "e_os.h"
 115 #include "cryptlib.h"
 116 #include <openssl/rand.h>
 117 #include "rand_lcl.h"
 118
 119 #if !(defined(OPENSSL_SYS_WINDOWS) || defined(OPENSSL_SYS_WIN32) || defined(OPENSSL_SYS_VMS) || defined(OPENSSL_SYS_OS2) || defined(OPENSSL_SYS_VXWORKS) || defined(OPENSSL_SYS_NETWARE))
 120
 121 # include <sys/types.h>
 122 # include <sys/time.h>
 123 # include <sys/times.h>
 124 # include <sys/stat.h>
 125 # include <fcntl.h>
 126 # include <unistd.h>
 127 # include <time.h>
 128 # if defined(OPENSSL_SYS_LINUX) /* should actually be available virtually
 129                                  * everywhere */
 130 #  include <poll.h>
 131 # endif
 132 # include <limits.h>
 133 # ifndef FD_SETSIZE
 134 #  define FD_SETSIZE (8*sizeof(fd_set))
 135 # endif
 136
 137 # if defined(OPENSSL_SYS_VOS)
 138
 139 /*
 140  * The following algorithm repeatedly samples the real-time clock (RTC) to
 141  * generate a sequence of unpredictable data.  The algorithm relies upon the
 142  * uneven execution speed of the code (due to factors such as cache misses,
 143  * interrupts, bus activity, and scheduling) and upon the rather large
 144  * relative difference between the speed of the clock and the rate at which
 145  * it can be read.
 146  *
 147  * If this code is ported to an environment where execution speed is more
 148  * constant or where the RTC ticks at a much slower rate, or the clock can be
 149  * read with fewer instructions, it is likely that the results would be far
 150  * more predictable.
 151  *
 152  * As a precaution, we generate 4 times the minimum required amount of seed
 153  * data.
 154  */
 155
 156 int RAND_poll(void)
 157 {
 158     short int code;
 159     gid_t curr_gid;
 160     pid_t curr_pid;
 161     uid_t curr_uid;
 162     int i, k;
 163     struct timespec ts;
 164     unsigned char v;
 165
 166 #  ifdef OPENSSL_SYS_VOS_HPPA
 167     long duration;
 168     extern void s$sleep(long *_duration, short int *_code);
 169 #  else
 170 #   ifdef OPENSSL_SYS_VOS_IA32
 171     long long duration;
 172     extern void s$sleep2(long long *_duration, short int *_code);
 173 #   else
 174 #    error "Unsupported Platform."
 175 #   endif                       /* OPENSSL_SYS_VOS_IA32 */
 176 #  endif                        /* OPENSSL_SYS_VOS_HPPA */
 177
 178     /*
 179      * Seed with the gid, pid, and uid, to ensure *some* variation between
 180      * different processes.
 181      */
 182
 183     curr_gid = getgid();
 184     RAND_add(&curr_gid, sizeof curr_gid, 1);
 185     curr_gid = 0;
 186
 187     curr_pid = getpid();
 188     RAND_add(&curr_pid, sizeof curr_pid, 1);
 189     curr_pid = 0;
 190
 191     curr_uid = getuid();
 192     RAND_add(&curr_uid, sizeof curr_uid, 1);
 193     curr_uid = 0;
 194
 195     for (i = 0; i < (ENTROPY_NEEDED * 4); i++) {
 196         /*
 197          * burn some cpu; hope for interrupts, cache collisions, bus
 198          * interference, etc.
 199          */
 200         for (k = 0; k < 99; k++)
 201             ts.tv_nsec = random();
 202
 203 #  ifdef OPENSSL_SYS_VOS_HPPA
 204         /* sleep for 1/1024 of a second (976 us).  */
 205         duration = 1;
 206         s$sleep(&duration, &code);
 207 #  else
 208 #   ifdef OPENSSL_SYS_VOS_IA32
 209         /* sleep for 1/65536 of a second (15 us).  */
 210         duration = 1;
 211         s$sleep2(&duration, &code);
 212 #   endif                       /* OPENSSL_SYS_VOS_IA32 */
 213 #  endif                        /* OPENSSL_SYS_VOS_HPPA */
 214
 215         /* get wall clock time.  */
 216         clock_gettime(CLOCK_REALTIME, &ts);
 217
 218         /* take 8 bits */
 219         v = (unsigned char)(ts.tv_nsec % 256);
 220         RAND_add(&v, sizeof v, 1);
 221         v = 0;
 222     }
 223     return 1;
 224 }
 225 # elif defined __OpenBSD__
 226 int RAND_poll(void)
 227 {
 228     u_int32_t rnd = 0, i;
 229     unsigned char buf[ENTROPY_NEEDED];
 230
 231     for (i = 0; i < sizeof(buf); i++) {
 232         if (i % 4 == 0)
 233             rnd = arc4random();
 234         buf[i] = rnd;
 235         rnd >>= 8;
 236     }
 237     RAND_add(buf, sizeof(buf), ENTROPY_NEEDED);
 238     memset(buf, 0, sizeof(buf));
 239
 240     return 1;
 241 }
 242 # else                          /* !defined(__OpenBSD__) */
 243 int RAND_poll(void)
 244 {
 245     unsigned long l;
 246     pid_t curr_pid = getpid();
 247 #  if defined(DEVRANDOM) || defined(DEVRANDOM_EGD)
 248     unsigned char tmpbuf[ENTROPY_NEEDED];
 249     int n = 0;
 250 #  endif
 251 #  ifdef DEVRANDOM
 252     static const char *randomfiles[] = { DEVRANDOM };
 253     struct stat randomstats[sizeof(randomfiles) / sizeof(randomfiles[0])];
 254     int fd;
 255     unsigned int i;
 256 #  endif
 257 #  ifdef DEVRANDOM_EGD
 258     static const char *egdsockets[] = { DEVRANDOM_EGD, NULL };
 259     const char **egdsocket = NULL;
 260 #  endif
 261
 262 #  ifdef DEVRANDOM
 263     memset(randomstats, 0, sizeof(randomstats));
 264     /*
 265      * Use a random entropy pool device. Linux, FreeBSD and OpenBSD have
 266      * this. Use /dev/urandom if you can as /dev/random may block if it runs
 267      * out of random entries.
 268      */
 269
 270     for (i = 0; (i < sizeof(randomfiles) / sizeof(randomfiles[0])) &&
 271          (n < ENTROPY_NEEDED); i++) {
 272         if ((fd = open(randomfiles[i], O_RDONLY
 273 #   ifdef O_NONBLOCK
 274                        | O_NONBLOCK
 275 #   endif
 276 #   ifdef O_BINARY
 277                        | O_BINARY
 278 #   endif
 279 #   ifdef O_NOCTTY              /* If it happens to be a TTY (god forbid), do
 280                                  * not make it our controlling tty */
 281                        | O_NOCTTY
 282 #   endif
 283              )) >= 0) {
 284             int usec = 10 * 1000; /* spend 10ms on each file */
 285             int r;
 286             unsigned int j;
 287             struct stat *st = &randomstats[i];
 288
 289             /*
 290              * Avoid using same input... Used to be O_NOFOLLOW above, but
 291              * it's not universally appropriate...
 292              */
 293             if (fstat(fd, st) != 0) {
 294                 close(fd);
 295                 continue;
 296             }
 297             for (j = 0; j < i; j++) {
 298                 if (randomstats[j].st_ino == st->st_ino &&
 299                     randomstats[j].st_dev == st->st_dev)
 300                     break;
 301             }
 302             if (j < i) {
 303                 close(fd);
 304                 continue;
 305             }
 306
 307             do {
 308                 int try_read = 0;
 309
 310 #   if defined(OPENSSL_SYS_BEOS_R5)
 311                 /*
 312                  * select() is broken in BeOS R5, so we simply try to read
 313                  * something and snooze if we couldn't
 314                  */
 315                 try_read = 1;
 316
 317 #   elif defined(OPENSSL_SYS_LINUX)
 318                 /* use poll() */
 319                 struct pollfd pset;
 320
 321                 pset.fd = fd;
 322                 pset.events = POLLIN;
 323                 pset.revents = 0;
 324
 325                 if (poll(&pset, 1, usec / 1000) < 0)
 326                     usec = 0;
 327                 else
 328                     try_read = (pset.revents & POLLIN) != 0;
 329
 330 #   else
 331                 /* use select() */
 332                 fd_set fset;
 333                 struct timeval t;
 334
 335                 t.tv_sec = 0;
 336                 t.tv_usec = usec;
 337
 338                 if (FD_SETSIZE > 0 && (unsigned)fd >= FD_SETSIZE) {
 339                     /*
 340                      * can't use select, so just try to read once anyway
 341                      */
 342                     try_read = 1;
 343                 } else {
 344                     FD_ZERO(&fset);
 345                     FD_SET(fd, &fset);
 346
 347                     if (select(fd + 1, &fset, NULL, NULL, &t) >= 0) {
 348                         usec = t.tv_usec;
 349                         if (FD_ISSET(fd, &fset))
 350                             try_read = 1;
 351                     } else
 352                         usec = 0;
 353                 }
 354 #   endif
 355
 356                 if (try_read) {
 357                     r = read(fd, (unsigned char *)tmpbuf + n,
 358                              ENTROPY_NEEDED - n);
 359                     if (r > 0)
 360                         n += r;
 361 #   if defined(OPENSSL_SYS_BEOS_R5)
 362                     if (r == 0)
 363                         snooze(t.tv_usec);
 364 #   endif
 365                 } else
 366                     r = -1;
 367
 368                 /*
 369                  * Some Unixen will update t in select(), some won't.  For
 370                  * those who won't, or if we didn't use select() in the first
 371                  * place, give up here, otherwise, we will do this once again
 372                  * for the remaining time.
 373                  */
 374                 if (usec == 10 * 1000)
 375                     usec = 0;
 376             }
 377             while ((r > 0 ||
 378                     (errno == EINTR || errno == EAGAIN)) && usec != 0
 379                    && n < ENTROPY_NEEDED);
 380
 381             close(fd);
 382         }
 383     }
 384 #  endif                        /* defined(DEVRANDOM) */
 385
 386 #  ifdef DEVRANDOM_EGD
 387     /*
 388      * Use an EGD socket to read entropy from an EGD or PRNGD entropy
 389      * collecting daemon.
 390      */
 391
 392     for (egdsocket = egdsockets; *egdsocket && n < ENTROPY_NEEDED;
 393          egdsocket++) {
 394         int r;
 395
 396         r = RAND_query_egd_bytes(*egdsocket, (unsigned char *)tmpbuf + n,
 397                                  ENTROPY_NEEDED - n);
 398         if (r > 0)
 399             n += r;
 400     }
 401 #  endif                        /* defined(DEVRANDOM_EGD) */
 402
 403 #  if defined(DEVRANDOM) || defined(DEVRANDOM_EGD)
 404     if (n > 0) {
 405         RAND_add(tmpbuf, sizeof tmpbuf, (double)n);
 406         OPENSSL_cleanse(tmpbuf, n);
 407     }
 408 #  endif
 409
 410     /* put in some default random data, we need more than just this */
 411     l = curr_pid;
 412     RAND_add(&l, sizeof(l), 0.0);
 413     l = getuid();
 414     RAND_add(&l, sizeof(l), 0.0);
 415
 416     l = time(NULL);
 417     RAND_add(&l, sizeof(l), 0.0);
 418
 419 #  if defined(OPENSSL_SYS_BEOS)
 420     {
 421         system_info sysInfo;
 422         get_system_info(&sysInfo);
 423         RAND_add(&sysInfo, sizeof(sysInfo), 0);
 424     }
 425 #  endif
 426
 427 #  if defined(DEVRANDOM) || defined(DEVRANDOM_EGD)
 428     return 1;
 429 #  else
 430     return 0;
 431 #  endif
 432 }
 433
 434 # endif                         /* defined(__OpenBSD__) */
 435 #endif                          /* !(defined(OPENSSL_SYS_WINDOWS) ||
 436                                  * defined(OPENSSL_SYS_WIN32) ||
 437                                  * defined(OPENSSL_SYS_VMS) ||
 438                                  * defined(OPENSSL_SYS_OS2) ||
 439                                  * defined(OPENSSL_SYS_VXWORKS) ||
 440                                  * defined(OPENSSL_SYS_NETWARE)) */
 441
 442 #if defined(OPENSSL_SYS_VXWORKS)
 443 int RAND_poll(void)
 444 {
 445     return 0;
 446 }
 447 #endif