crypto/dist/heimdal/lib/hcrypto/rand.c

   1 /*
   2  * Copyright (c) 2006 - 2007 Kungliga Tekniska Högskolan
   3  * (Royal Institute of Technology, Stockholm, Sweden).
   4  * 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 the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * 3. Neither the name of the Institute nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #ifdef HAVE_CONFIG_H
  35 #include <config.h>
  36 #endif
  37
  38 __RCSID("$Heimdal: rand.c 22199 2007-12-07 13:43:25Z lha $"
  39         "$NetBSD$");
  40
  41 #include <stdio.h>
  42 #include <stdlib.h>
  43 #include <rand.h>
  44 #include <randi.h>
  45
  46 #include <roken.h>
  47
  48 #ifndef O_BINARY
  49 #define O_BINARY 0
  50 #endif
  51
  52
  53 const static RAND_METHOD *selected_meth = NULL;
  54
  55 static void
  56 init_method(void)
  57 {
  58     if (selected_meth != NULL)
  59         return;
  60     selected_meth = &hc_rand_fortuna_method;
  61 }
  62
  63 void
  64 RAND_seed(const void *indata, size_t size)
  65 {
  66     init_method();
  67     (*selected_meth->seed)(indata, size);
  68 }
  69
  70 int
  71 RAND_bytes(void *outdata, size_t size)
  72 {
  73     init_method();
  74     return (*selected_meth->bytes)(outdata, size);
  75 }
  76
  77 void
  78 RAND_cleanup(void)
  79 {
  80     init_method();
  81     (*selected_meth->cleanup)();
  82 }
  83
  84 void
  85 RAND_add(const void *indata, size_t size, double entropi)
  86 {
  87     init_method();
  88     (*selected_meth->add)(indata, size, entropi);
  89 }
  90
  91 int
  92 RAND_pseudo_bytes(void *outdata, size_t size)
  93 {
  94     init_method();
  95     return (*selected_meth->pseudorand)(outdata, size);
  96 }
  97
  98 int
  99 RAND_status(void)
 100 {
 101     init_method();
 102     return (*selected_meth->status)();
 103 }
 104
 105 int
 106 RAND_set_rand_method(const RAND_METHOD *meth)
 107 {
 108     selected_meth = meth;
 109     return 1;
 110 }
 111
 112 const RAND_METHOD *
 113 RAND_get_rand_method(void)
 114 {
 115     return selected_meth;
 116 }
 117
 118 int
 119 RAND_set_rand_engine(ENGINE *engine)
 120 {
 121     return 1;
 122 }
 123
 124 #define RAND_FILE_SIZE 1024
 125
 126 int
 127 RAND_load_file(const char *filename, size_t size)
 128 {
 129     unsigned char buf[128];
 130     size_t len;
 131     ssize_t slen;
 132     int fd;
 133
 134     fd = open(filename, O_RDONLY | O_BINARY, 0600);
 135     if (fd < 0)
 136         return 0;
 137
 138     len = 0;
 139     while(len < size) {
 140         slen = read(fd, buf, sizeof(buf));
 141         if (slen <= 0)
 142             break;
 143         RAND_seed(buf, slen);
 144         len += slen;
 145     }
 146     close(fd);
 147
 148     return len ? 1 : 0;
 149 }
 150
 151 int
 152 RAND_write_file(const char *filename)
 153 {
 154     unsigned char buf[128];
 155     size_t len;
 156     int res = 0, fd;
 157
 158     fd = open(filename, O_WRONLY | O_CREAT | O_BINARY, 0600);
 159     if (fd < 0)
 160         return 0;
 161
 162     len = 0;
 163     while(len < RAND_FILE_SIZE) {
 164         res = RAND_bytes(buf, sizeof(buf));
 165         if (res != 1)
 166             break;
 167         if (write(fd, buf, sizeof(buf)) != sizeof(buf)) {
 168             res = 0;
 169             break;
 170         }
 171         len += sizeof(buf);
 172     }
 173
 174     close(fd);
 175
 176     return res;
 177 }
 178
 179 const char *
 180 RAND_file_name(char *filename, size_t size)
 181 {
 182     const char *e = NULL;
 183     int pathp = 0, ret;
 184
 185     if (!issuid()) {
 186         e = getenv("RANDFILE");
 187         if (e == NULL) {
 188             e = getenv("HOME");
 189             if (e)
 190                 pathp = 1;
 191         }
 192     }
 193     /*
 194      * Here we really want to call getpwuid(getuid()) but this will
 195      * cause recursive lookups if the nss library uses
 196      * gssapi/krb5/hcrypto to authenticate to the ldap servers.
 197      */
 198
 199     if (e == NULL)
 200         return NULL;
 201
 202     if (pathp)
 203         ret = snprintf(filename, size, "%s/.rnd", e);
 204     else
 205         ret = snprintf(filename, size, "%s", e);
 206
 207     if (ret <= 0 || ret >= size)
 208         return NULL;
 209
 210     return filename;
 211 }