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 #include <openssl/buffer.h>
  60
  61 /*
  62  * Query the EGD <URL: http://www.lothar.com/tech/crypto/>.
  63  *
  64  * This module supplies three routines:
  65  *
  66  * RAND_query_egd_bytes(path, buf, bytes)
  67  *   will actually query "bytes" bytes of entropy form the egd-socket located
  68  *   at path and will write them to buf (if supplied) or will directly feed
  69  *   it to RAND_seed() if buf==NULL.
  70  *   The number of bytes is not limited by the maximum chunk size of EGD,
  71  *   which is 255 bytes. If more than 255 bytes are wanted, several chunks
  72  *   of entropy bytes are requested. The connection is left open until the
  73  *   query is competed.
  74  *   RAND_query_egd_bytes() returns with
  75  *     -1  if an error occured during connection or communication.
  76  *     num the number of bytes read from the EGD socket. This number is either
  77  *         the number of bytes requested or smaller, if the EGD pool is
  78  *         drained and the daemon signals that the pool is empty.
  79  *   This routine does not touch any RAND_status(). This is necessary, since
  80  *   PRNG functions may call it during initialization.
  81  *
  82  * RAND_egd_bytes(path, bytes) will query "bytes" bytes and have them
  83  *   used to seed the PRNG.
  84  *   RAND_egd_bytes() is a wrapper for RAND_query_egd_bytes() with buf=NULL.
  85  *   Unlike RAND_query_egd_bytes(), RAND_status() is used to test the
  86  *   seed status so that the return value can reflect the seed state:
  87  *     -1  if an error occured during connection or communication _or_
  88  *         if the PRNG has still not received the required seeding.
  89  *     num the number of bytes read from the EGD socket. This number is either
  90  *         the number of bytes requested or smaller, if the EGD pool is
  91  *         drained and the daemon signals that the pool is empty.
  92  *
  93  * RAND_egd(path) will query 255 bytes and use the bytes retreived to seed
  94  *   the PRNG.
  95  *   RAND_egd() is a wrapper for RAND_egd_bytes() with numbytes=255.
  96  */
  97
  98 #if defined(OPENSSL_SYS_WIN32) || defined(OPENSSL_SYS_VMS) || defined(OPENSSL_SYS_MSDOS) || defined(OPENSSL_SYS_VXWORKS) || defined(OPENSSL_SYS_NETWARE) || defined(OPENSSL_SYS_VOS)
  99 int RAND_query_egd_bytes(const char *path, unsigned char *buf, int bytes)
 100         {
 101         return(-1);
 102         }
 103 int RAND_egd(const char *path)
 104         {
 105         return(-1);
 106         }
 107
 108 int RAND_egd_bytes(const char *path,int bytes)
 109         {
 110         return(-1);
 111         }
 112 #else
 113 #include <openssl/opensslconf.h>
 114 #include OPENSSL_UNISTD
 115 #include <sys/types.h>
 116 #include <sys/socket.h>
 117 #ifndef NO_SYS_UN_H
 118 # ifdef OPENSSL_SYS_VXWORKS
 119 #   include <streams/un.h>
 120 # else
 121 #   include <sys/un.h>
 122 # endif
 123 #else
 124 struct  sockaddr_un {
 125         short   sun_family;             /* AF_UNIX */
 126         char    sun_path[108];          /* path name (gag) */
 127 };
 128 #endif /* NO_SYS_UN_H */
 129 #include <string.h>
 130 #include <errno.h>
 131
 132 #ifndef offsetof
 133 #  define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
 134 #endif
 135
 136 int RAND_query_egd_bytes(const char *path, unsigned char *buf, int bytes)
 137         {
 138         int ret = 0;
 139         struct sockaddr_un addr;
 140         int len, num, numbytes;
 141         int fd = -1;
 142         int success;
 143         unsigned char egdbuf[2], tempbuf[255], *retrievebuf;
 144
 145         memset(&addr, 0, sizeof(addr));
 146         addr.sun_family = AF_UNIX;
 147         if (strlen(path) >= sizeof(addr.sun_path))
 148                 return (-1);
 149         BUF_strlcpy(addr.sun_path,path,sizeof addr.sun_path);
 150         len = offsetof(struct sockaddr_un, sun_path) + strlen(path);
 151         fd = socket(AF_UNIX, SOCK_STREAM, 0);
 152         if (fd == -1) return (-1);
 153         success = 0;
 154         while (!success)
 155             {
 156             if (connect(fd, (struct sockaddr *)&addr, len) == 0)
 157                success = 1;
 158             else
 159                 {
 160                 switch (errno)
 161                     {
 162 #ifdef EINTR
 163                     case EINTR:
 164 #endif
 165 #ifdef EAGAIN
 166                     case EAGAIN:
 167 #endif
 168 #ifdef EINPROGRESS
 169                     case EINPROGRESS:
 170 #endif
 171 #ifdef EALREADY
 172                     case EALREADY:
 173 #endif
 174                         /* No error, try again */
 175                         break;
 176 #ifdef EISCONN
 177                     case EISCONN:
 178                         success = 1;
 179                         break;
 180 #endif
 181                     default:
 182                         goto err;       /* failure */
 183                     }
 184                 }
 185             }
 186
 187         while(bytes > 0)
 188             {
 189             egdbuf[0] = 1;
 190             egdbuf[1] = bytes < 255 ? bytes : 255;
 191             numbytes = 0;
 192             while (numbytes != 2)
 193                 {
 194                 num = write(fd, egdbuf + numbytes, 2 - numbytes);
 195                 if (num >= 0)
 196                     numbytes += num;
 197                 else
 198                     {
 199                     switch (errno)
 200                         {
 201 #ifdef EINTR
 202                         case EINTR:
 203 #endif
 204 #ifdef EAGAIN
 205                         case EAGAIN:
 206 #endif
 207                             /* No error, try again */
 208                             break;
 209                         default:
 210                             ret = -1;
 211                             goto err;   /* failure */
 212                         }
 213                     }
 214                 }
 215             numbytes = 0;
 216             while (numbytes != 1)
 217                 {
 218                 num = read(fd, egdbuf, 1);
 219                 if (num >= 0)
 220                     numbytes += num;
 221                 else
 222                     {
 223                     switch (errno)
 224                         {
 225 #ifdef EINTR
 226                         case EINTR:
 227 #endif
 228 #ifdef EAGAIN
 229                         case EAGAIN:
 230 #endif
 231                             /* No error, try again */
 232                             break;
 233                         default:
 234                             ret = -1;
 235                             goto err;   /* failure */
 236                         }
 237                     }
 238                 }
 239             if(egdbuf[0] == 0)
 240                 goto err;
 241             if (buf)
 242                 retrievebuf = buf + ret;
 243             else
 244                 retrievebuf = tempbuf;
 245             numbytes = 0;
 246             while (numbytes != egdbuf[0])
 247                 {
 248                 num = read(fd, retrievebuf + numbytes, egdbuf[0] - numbytes);
 249                 if (num >= 0)
 250                     numbytes += num;
 251                 else
 252                     {
 253                     switch (errno)
 254                         {
 255 #ifdef EINTR
 256                         case EINTR:
 257 #endif
 258 #ifdef EAGAIN
 259                         case EAGAIN:
 260 #endif
 261                             /* No error, try again */
 262                             break;
 263                         default:
 264                             ret = -1;
 265                             goto err;   /* failure */
 266                         }
 267                     }
 268                 }
 269             ret += egdbuf[0];
 270             bytes -= egdbuf[0];
 271             if (!buf)
 272                 RAND_seed(tempbuf, egdbuf[0]);
 273             }
 274  err:
 275         if (fd != -1) close(fd);
 276         return(ret);
 277         }
 278
 279
 280 int RAND_egd_bytes(const char *path, int bytes)
 281         {
 282         int num, ret = 0;
 283
 284         num = RAND_query_egd_bytes(path, NULL, bytes);
 285         if (num < 1) goto err;
 286         if (RAND_status() == 1)
 287             ret = num;
 288  err:
 289         return(ret);
 290         }
 291
 292
 293 int RAND_egd(const char *path)
 294         {
 295         return (RAND_egd_bytes(path, 255));
 296         }
 297
 298
 299 #endif