crypto/rand/randfile.c

   1 /* crypto/rand/randfile.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 #include <errno.h>
  60 #include <stdio.h>
  61 #include <stdlib.h>
  62 #include <string.h>
  63
  64 #include "openssl/e_os.h"
  65
  66 #ifdef VMS
  67 #include <unixio.h>
  68 #endif
  69 #ifndef NO_SYS_TYPES_H
  70 # include <sys/types.h>
  71 #endif
  72 #ifdef MAC_OS_pre_X
  73 # include <stat.h>
  74 #else
  75 # include <sys/stat.h>
  76 #endif
  77
  78 #include <openssl/crypto.h>
  79 #include <openssl/rand.h>
  80
  81 #undef BUFSIZE
  82 #define BUFSIZE 1024
  83 #define RAND_DATA 1024
  84
  85 /* #define RFILE ".rnd" - defined in ../../e_os.h */
  86
  87 int RAND_load_file(const char *file, long bytes)
  88         {
  89         /* If bytes >= 0, read up to 'bytes' bytes.
  90          * if bytes == -1, read complete file. */
  91
  92         MS_STATIC unsigned char buf[BUFSIZE];
  93         struct stat sb;
  94         int i,ret=0,n;
  95         FILE *in;
  96
  97         if (file == NULL) return(0);
  98
  99         i=stat(file,&sb);
 100         /* If the state fails, put some crap in anyway */
 101         RAND_add(&sb,sizeof(sb),0);
 102         if (i < 0) return(0);
 103         if (bytes == 0) return(ret);
 104
 105         in=fopen(file,"rb");
 106         if (in == NULL) goto err;
 107         for (;;)
 108                 {
 109                 if (bytes > 0)
 110                         n = (bytes < BUFSIZE)?(int)bytes:BUFSIZE;
 111                 else
 112                         n = BUFSIZE;
 113                 i=fread(buf,1,n,in);
 114                 if (i <= 0) break;
 115                 /* even if n != i, use the full array */
 116                 RAND_add(buf,n,i);
 117                 ret+=i;
 118                 if (bytes > 0)
 119                         {
 120                         bytes-=n;
 121                         if (bytes == 0) break;
 122                         }
 123                 }
 124         fclose(in);
 125         memset(buf,0,BUFSIZE);
 126 err:
 127         return(ret);
 128         }
 129
 130 int RAND_write_file(const char *file)
 131         {
 132         unsigned char buf[BUFSIZE];
 133         int i,ret=0,err=0;
 134         FILE *out = NULL;
 135         int n;
 136
 137 #if defined(O_CREAT) && !defined(WIN32)
 138         /* For some reason Win32 can't write to files created this way */
 139
 140         /* chmod(..., 0600) is too late to protect the file,
 141          * permissions should be restrictive from the start */
 142         int fd = open(file, O_CREAT, 0600);
 143         if (fd != -1)
 144                 out = fdopen(fd, "wb");
 145 #endif
 146         if (out == NULL)
 147                 out = fopen(file,"wb");
 148         if (out == NULL) goto err;
 149
 150 #ifndef NO_CHMOD
 151         chmod(file,0600);
 152 #endif
 153         n=RAND_DATA;
 154         for (;;)
 155                 {
 156                 i=(n > BUFSIZE)?BUFSIZE:n;
 157                 n-=BUFSIZE;
 158                 if (RAND_bytes(buf,i) <= 0)
 159                         err=1;
 160                 i=fwrite(buf,1,i,out);
 161                 if (i <= 0)
 162                         {
 163                         ret=0;
 164                         break;
 165                         }
 166                 ret+=i;
 167                 if (n <= 0) break;
 168                 }
 169 #ifdef VMS
 170         /* Try to delete older versions of the file, until there aren't
 171            any */
 172         {
 173         char *tmpf;
 174
 175         tmpf = OPENSSL_malloc(strlen(file) + 4);  /* to add ";-1" and a nul */
 176         if (tmpf)
 177                 {
 178                 strcpy(tmpf, file);
 179                 strcat(tmpf, ";-1");
 180                 while(delete(tmpf) == 0)
 181                         ;
 182                 rename(file,";1"); /* Make sure it's version 1, or we
 183                                       will reach the limit (32767) at
 184                                       some point... */
 185                 }
 186         }
 187 #endif /* VMS */
 188
 189         fclose(out);
 190         memset(buf,0,BUFSIZE);
 191 err:
 192         return(err ? -1 : ret);
 193         }
 194
 195 const char *RAND_file_name(char *buf, int size)
 196         {
 197         char *s;
 198         char *ret=NULL;
 199
 200         s=getenv("RANDFILE");
 201         if (s != NULL)
 202                 {
 203                 strncpy(buf,s,size-1);
 204                 buf[size-1]='\0';
 205                 ret=buf;
 206                 }
 207         else
 208                 {
 209                 s=getenv("HOME");
 210                 if (s == NULL) return(RFILE);
 211                 if (((int)(strlen(s)+strlen(RFILE)+2)) > size)
 212                         return(RFILE);
 213                 strcpy(buf,s);
 214 #ifndef VMS
 215                 strcat(buf,"/");
 216 #endif
 217                 strcat(buf,RFILE);
 218                 ret=buf;
 219                 }
 220         return(ret);
 221         }