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/crypto.h>
  58 #include <openssl/e_os2.h>
  59 #include <openssl/rand.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 occurred 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 occurred 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) || defined(OPENSSL_SYS_UEFI)
  99 int RAND_query_egd_bytes(const char *path, unsigned char *buf, int bytes)
 100 {
 101     return (-1);
 102 }
 103
 104 int RAND_egd(const char *path)
 105 {
 106     return (-1);
 107 }
 108
 109 int RAND_egd_bytes(const char *path, int bytes)
 110 {
 111     return (-1);
 112 }
 113 #else
 114 # include <openssl/opensslconf.h>
 115 # include OPENSSL_UNISTD
 116 # include <stddef.h>
 117 # include <sys/types.h>
 118 # include <sys/socket.h>
 119 # ifndef NO_SYS_UN_H
 120 #  ifdef OPENSSL_SYS_VXWORKS
 121 #   include <streams/un.h>
 122 #  else
 123 #   include <sys/un.h>
 124 #  endif
 125 # else
 126 struct sockaddr_un {
 127     short sun_family;           /* AF_UNIX */
 128     char sun_path[108];         /* path name (gag) */
 129 };
 130 # endif                         /* NO_SYS_UN_H */
 131 # include <string.h>
 132 # include <errno.h>
 133
 134 int RAND_query_egd_bytes(const char *path, unsigned char *buf, int bytes)
 135 {
 136     int ret = 0;
 137     struct sockaddr_un addr;
 138     int len, num, numbytes;
 139     int fd = -1;
 140     int success;
 141     unsigned char egdbuf[2], tempbuf[255], *retrievebuf;
 142
 143     memset(&addr, 0, sizeof(addr));
 144     addr.sun_family = AF_UNIX;
 145     if (strlen(path) >= sizeof(addr.sun_path))
 146         return (-1);
 147     OPENSSL_strlcpy(addr.sun_path, path, sizeof addr.sun_path);
 148     len = offsetof(struct sockaddr_un, sun_path) + strlen(path);
 149     fd = socket(AF_UNIX, SOCK_STREAM, 0);
 150     if (fd == -1)
 151         return (-1);
 152     success = 0;
 153     while (!success) {
 154         if (connect(fd, (struct sockaddr *)&addr, len) == 0)
 155             success = 1;
 156         else {
 157             switch (errno) {
 158 # ifdef EINTR
 159             case EINTR:
 160 # endif
 161 # ifdef EAGAIN
 162             case EAGAIN:
 163 # endif
 164 # ifdef EINPROGRESS
 165             case EINPROGRESS:
 166 # endif
 167 # ifdef EALREADY
 168             case EALREADY:
 169 # endif
 170                 /* No error, try again */
 171                 break;
 172 # ifdef EISCONN
 173             case EISCONN:
 174                 success = 1;
 175                 break;
 176 # endif
 177             default:
 178                 goto err;       /* failure */
 179             }
 180         }
 181     }
 182
 183     while (bytes > 0) {
 184         egdbuf[0] = 1;
 185         egdbuf[1] = bytes < 255 ? bytes : 255;
 186         numbytes = 0;
 187         while (numbytes != 2) {
 188             num = write(fd, egdbuf + numbytes, 2 - numbytes);
 189             if (num >= 0)
 190                 numbytes += num;
 191             else {
 192                 switch (errno) {
 193 # ifdef EINTR
 194                 case EINTR:
 195 # endif
 196 # ifdef EAGAIN
 197                 case EAGAIN:
 198 # endif
 199                     /* No error, try again */
 200                     break;
 201                 default:
 202                     ret = -1;
 203                     goto err;   /* failure */
 204                 }
 205             }
 206         }
 207         numbytes = 0;
 208         while (numbytes != 1) {
 209             num = read(fd, egdbuf, 1);
 210             if (num == 0)
 211                 goto err;       /* descriptor closed */
 212             else if (num > 0)
 213                 numbytes += num;
 214             else {
 215                 switch (errno) {
 216 # ifdef EINTR
 217                 case EINTR:
 218 # endif
 219 # ifdef EAGAIN
 220                 case EAGAIN:
 221 # endif
 222                     /* No error, try again */
 223                     break;
 224                 default:
 225                     ret = -1;
 226                     goto err;   /* failure */
 227                 }
 228             }
 229         }
 230         if (egdbuf[0] == 0)
 231             goto err;
 232         if (buf)
 233             retrievebuf = buf + ret;
 234         else
 235             retrievebuf = tempbuf;
 236         numbytes = 0;
 237         while (numbytes != egdbuf[0]) {
 238             num = read(fd, retrievebuf + numbytes, egdbuf[0] - numbytes);
 239             if (num == 0)
 240                 goto err;       /* descriptor closed */
 241             else if (num > 0)
 242                 numbytes += num;
 243             else {
 244                 switch (errno) {
 245 # ifdef EINTR
 246                 case EINTR:
 247 # endif
 248 # ifdef EAGAIN
 249                 case EAGAIN:
 250 # endif
 251                     /* No error, try again */
 252                     break;
 253                 default:
 254                     ret = -1;
 255                     goto err;   /* failure */
 256                 }
 257             }
 258         }
 259         ret += egdbuf[0];
 260         bytes -= egdbuf[0];
 261         if (!buf)
 262             RAND_seed(tempbuf, egdbuf[0]);
 263     }
 264  err:
 265     if (fd != -1)
 266         close(fd);
 267     return (ret);
 268 }
 269
 270 int RAND_egd_bytes(const char *path, int bytes)
 271 {
 272     int num, ret = 0;
 273
 274     num = RAND_query_egd_bytes(path, NULL, bytes);
 275     if (num < 1)
 276         goto err;
 277     if (RAND_status() == 1)
 278         ret = num;
 279  err:
 280     return (ret);
 281 }
 282
 283 int RAND_egd(const char *path)
 284 {
 285     return (RAND_egd_bytes(path, 255));
 286 }
 287
 288 #endif