crypto/rand/rand_egd.c

   1 /* crypto/rand/rand_egd.c */
   2 /* Written by Ulf Moeller and Lutz Jaenicke for the OpenSSL project. */
   3 /* ====================================================================
   4  * Copyright (c) 1998-2000 The OpenSSL Project.  All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  *
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  *
  18  * 3. All advertising materials mentioning features or use of this
  19  *    software must display the following acknowledgment:
  20  *    "This product includes software developed by the OpenSSL Project
  21  *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
  22  *
  23  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
  24  *    endorse or promote products derived from this software without
  25  *    prior written permission. For written permission, please contact
  26  *    openssl-core@openssl.org.
  27  *
  28  * 5. Products derived from this software may not be called "OpenSSL"
  29  *    nor may "OpenSSL" appear in their names without prior written
  30  *    permission of the OpenSSL Project.
  31  *
  32  * 6. Redistributions of any form whatsoever must retain the following
  33  *    acknowledgment:
  34  *    "This product includes software developed by the OpenSSL Project
  35  *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
  36  *
  37  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
  38  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  39  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  40  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
  41  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  42  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  43  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  44  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  45  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  46  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  47  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  48  * OF THE POSSIBILITY OF SUCH DAMAGE.
  49  * ====================================================================
  50  *
  51  * This product includes cryptographic software written by Eric Young
  52  * (eay@cryptsoft.com).  This product includes software written by Tim
  53  * Hudson (tjh@cryptsoft.com).
  54  *
  55  */
  56
  57 #include <openssl/e_os2.h>
  58 #include <openssl/rand.h>
  59
  60 /*
  61  * Query the EGD <URL: http://www.lothar.com/tech/crypto/>.
  62  *
  63  * This module supplies three routines:
  64  *
  65  * RAND_query_egd_bytes(path, buf, bytes)
  66  *   will actually query "bytes" bytes of entropy form the egd-socket located
  67  *   at path and will write them to buf (if supplied) or will directly feed
  68  *   it to RAND_seed() if buf==NULL.
  69  *   The number of bytes is not limited by the maximum chunk size of EGD,
  70  *   which is 255 bytes. If more than 255 bytes are wanted, several chunks
  71  *   of entropy bytes are requested. The connection is left open until the
  72  *   query is competed.
  73  *   RAND_query_egd_bytes() returns with
  74  *     -1  if an error occured during connection or communication.
  75  *     num the number of bytes read from the EGD socket. This number is either
  76  *         the number of bytes requested or smaller, if the EGD pool is
  77  *         drained and the daemon signals that the pool is empty.
  78  *   This routine does not touch any RAND_status(). This is necessary, since
  79  *   PRNG functions may call it during initialization.
  80  *
  81  * RAND_egd_bytes(path, bytes) will query "bytes" bytes and have them
  82  *   used to seed the PRNG.
  83  *   RAND_egd_bytes() is a wrapper for RAND_query_egd_bytes() with buf=NULL.
  84  *   Unlike RAND_query_egd_bytes(), RAND_status() is used to test the
  85  *   seed status so that the return value can reflect the seed state:
  86  *     -1  if an error occured during connection or communication _or_
  87  *         if the PRNG has still not received the required seeding.
  88  *     num the number of bytes read from the EGD socket. This number is either
  89  *         the number of bytes requested or smaller, if the EGD pool is
  90  *         drained and the daemon signals that the pool is empty.
  91  *
  92  * RAND_egd(path) will query 255 bytes and use the bytes retreived to seed
  93  *   the PRNG.
  94  *   RAND_egd() is a wrapper for RAND_egd_bytes() with numbytes=255.
  95  */
  96
  97 #if defined(OPENSSL_SYS_WIN32) || defined(OPENSSL_SYS_VMS) || defined(OPENSSL_SYS_MSDOS) || defined(OPENSSL_SYS_VXWORKS) || defined(OPENSSL_SYS_NETWARE)
  98 int RAND_query_egd_bytes(const char *path, unsigned char *buf, int bytes)
  99         {
 100         return(-1);
 101         }
 102 int RAND_egd(const char *path)
 103         {
 104         return(-1);
 105         }
 106
 107 int RAND_egd_bytes(const char *path,int bytes)
 108         {
 109         return(-1);
 110         }
 111 #else
 112 #include <openssl/opensslconf.h>
 113 #include OPENSSL_UNISTD
 114 #include <sys/types.h>
 115 #include <sys/socket.h>
 116 #ifndef NO_SYS_UN_H
 117 # ifdef OPENSSL_SYS_VXWORKS
 118 #   include <streams/un.h>
 119 # else
 120 #   include <sys/un.h>
 121 # endif
 122 #else
 123 struct  sockaddr_un {
 124         short   sun_family;             /* AF_UNIX */
 125         char    sun_path[108];          /* path name (gag) */
 126 };
 127 #endif /* NO_SYS_UN_H */
 128 #include <string.h>
 129 #include <errno.h>
 130
 131 #ifndef offsetof
 132 #  define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
 133 #endif
 134
 135 int RAND_query_egd_bytes(const char *path, unsigned char *buf, int bytes)
 136         {
 137         int ret = 0;
 138         struct sockaddr_un addr;
 139         int len, num, numbytes;
 140         int fd = -1;
 141         int success;
 142         unsigned char egdbuf[2], tempbuf[255], *retrievebuf;
 143
 144         memset(&addr, 0, sizeof(addr));
 145         addr.sun_family = AF_UNIX;
 146         if (strlen(path) >= sizeof(addr.sun_path))
 147                 return (-1);
 148         strcpy(addr.sun_path,path);
 149         len = offsetof(struct sockaddr_un, sun_path) + strlen(path);
 150         fd = socket(AF_UNIX, SOCK_STREAM, 0);
 151         if (fd == -1) return (-1);
 152         success = 0;
 153         while (!success)
 154             {
 155             if (connect(fd, (struct sockaddr *)&addr, len) == 0)
 156                success = 1;
 157             else
 158                 {
 159                 switch (errno)
 160                     {
 161 #ifdef EINTR
 162                     case EINTR:
 163 #endif
 164 #ifdef EAGAIN
 165                     case EAGAIN:
 166 #endif
 167 #ifdef EINPROGRESS
 168                     case EINPROGRESS:
 169 #endif
 170 #ifdef EALREADY
 171                     case EALREADY:
 172 #endif
 173                         /* No error, try again */
 174                         break;
 175 #ifdef EISCONN
 176                     case EISCONN:
 177                         success = 1;
 178                         break;
 179 #endif
 180                     default:
 181                         goto err;       /* failure */
 182                     }
 183                 }
 184             }
 185
 186         while(bytes > 0)
 187             {
 188             egdbuf[0] = 1;
 189             egdbuf[1] = bytes < 255 ? bytes : 255;
 190             numbytes = 0;
 191             while (numbytes != 2)
 192                 {
 193                 num = write(fd, egdbuf + numbytes, 2 - numbytes);
 194                 if (num >= 0)
 195                     numbytes += num;
 196                 else
 197                     {
 198                     switch (errno)
 199                         {
 200 #ifdef EINTR
 201                         case EINTR:
 202 #endif
 203 #ifdef EAGAIN
 204                         case EAGAIN:
 205 #endif
 206                             /* No error, try again */
 207                             break;
 208                         default:
 209                             ret = -1;
 210                             goto err;   /* failure */
 211                         }
 212                     }
 213                 }
 214             numbytes = 0;
 215             while (numbytes != 1)
 216                 {
 217                 num = read(fd, egdbuf, 1);
 218                 if (num >= 0)
 219                     numbytes += num;
 220                 else
 221                     {
 222                     switch (errno)
 223                         {
 224 #ifdef EINTR
 225                         case EINTR:
 226 #endif
 227 #ifdef EAGAIN
 228                         case EAGAIN:
 229 #endif
 230                             /* No error, try again */
 231                             break;
 232                         default:
 233                             ret = -1;
 234                             goto err;   /* failure */
 235                         }
 236                     }
 237                 }
 238             if(egdbuf[0] == 0)
 239                 goto err;
 240             if (buf)
 241                 retrievebuf = buf + ret;
 242             else
 243                 retrievebuf = tempbuf;
 244             numbytes = 0;
 245             while (numbytes != egdbuf[0])
 246                 {
 247                 num = read(fd, retrievebuf + numbytes, egdbuf[0] - numbytes);
 248                 if (num >= 0)
 249                     numbytes += num;
 250                 else
 251                     {
 252                     switch (errno)
 253                         {
 254 #ifdef EINTR
 255                         case EINTR:
 256 #endif
 257 #ifdef EAGAIN
 258                         case EAGAIN:
 259 #endif
 260                             /* No error, try again */
 261                             break;
 262                         default:
 263                             ret = -1;
 264                             goto err;   /* failure */
 265                         }
 266                     }
 267                 }
 268             ret += egdbuf[0];
 269             bytes -= egdbuf[0];
 270             if (!buf)
 271                 RAND_seed(tempbuf, egdbuf[0]);
 272             }
 273  err:
 274         if (fd != -1) close(fd);
 275         return(ret);
 276         }
 277
 278
 279 int RAND_egd_bytes(const char *path, int bytes)
 280         {
 281         int num, ret = 0;
 282
 283         num = RAND_query_egd_bytes(path, NULL, bytes);
 284         if (num < 1) goto err;
 285         if (RAND_status() == 1)
 286             ret = num;
 287  err:
 288         return(ret);
 289         }
 290
 291
 292 int RAND_egd(const char *path)
 293         {
 294         return (RAND_egd_bytes(path, 255));
 295         }
 296
 297
 298 #endif