1 /* crypto/rand/randfile.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
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.
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).
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.
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
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)"
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
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.]
59 /* We need to define this to get macros like S_IFBLK and S_IFCHR */
60 #if !defined(OPENSSL_SYS_VXWORKS)
61 #define _XOPEN_SOURCE 500
70 #include <openssl/crypto.h>
71 #include <openssl/rand.h>
72 #include <openssl/buffer.h>
74 #ifdef OPENSSL_SYS_VMS
77 #ifndef NO_SYS_TYPES_H
78 # include <sys/types.h>
80 #ifndef OPENSSL_NO_POSIX_IO
81 # include <sys/stat.h>
88 #define fdopen _fdopen
93 #define RAND_DATA 1024
95 #ifdef OPENSSL_SYS_VMS
96 /* This declaration is a nasty hack to get around vms' extension to fopen
97 * for passing in sharing options being disabled by our /STANDARD=ANSI89 */
98 static FILE *(*const vms_fopen)(const char *, const char *, ...) =
99 (FILE *(*)(const char *, const char *, ...))fopen;
100 #define VMS_OPEN_ATTRS "shr=get,put,upd,del","ctx=bin,stm","rfm=stm","rat=none","mrs=0"
103 /* #define RFILE ".rnd" - defined in ../../e_os.h */
105 /* Note that these functions are intended for seed files only.
106 * Entropy devices and EGD sockets are handled in rand_unix.c */
108 int RAND_load_file(const char *file, long bytes)
110 /* If bytes >= 0, read up to 'bytes' bytes.
111 * if bytes == -1, read complete file. */
113 MS_STATIC unsigned char buf[BUFSIZE];
114 #ifndef OPENSSL_NO_POSIX_IO
120 if (file == NULL) return(0);
122 #ifndef OPENSSL_NO_POSIX_IO
124 /* struct stat can have padding and unused fields that may not be
125 * initialized in the call to stat(). We need to clear the entire
126 * structure before calling RAND_add() to avoid complaints from
127 * applications such as Valgrind.
129 memset(&sb, 0, sizeof(sb));
131 if (stat(file,&sb) < 0) return(0);
132 RAND_add(&sb,sizeof(sb),0.0);
134 if (bytes == 0) return(ret);
136 #ifdef OPENSSL_SYS_VMS
137 in=vms_fopen(file,"rb",VMS_OPEN_ATTRS);
141 if (in == NULL) goto err;
142 #if defined(S_IFBLK) && defined(S_IFCHR) && !defined(OPENSSL_NO_POSIX_IO)
143 if (sb.st_mode & (S_IFBLK | S_IFCHR)) {
144 /* this file is a device. we don't want read an infinite number
145 * of bytes from a random device, nor do we want to use buffered
146 * I/O because we will waste system entropy.
148 bytes = (bytes == -1) ? 2048 : bytes; /* ok, is 2048 enough? */
149 #ifndef OPENSSL_NO_SETVBUF_IONBF
150 setvbuf(in, NULL, _IONBF, 0); /* don't do buffered reads */
151 #endif /* ndef OPENSSL_NO_SETVBUF_IONBF */
157 n = (bytes < BUFSIZE)?(int)bytes:BUFSIZE;
163 RAND_add(buf,i,(double)i);
165 /* even if n != i, use the full array */
166 RAND_add(buf,n,(double)i);
172 if (bytes <= 0) break;
176 OPENSSL_cleanse(buf,BUFSIZE);
181 int RAND_write_file(const char *file)
183 unsigned char buf[BUFSIZE];
184 int i,ret=0,rand_err=0;
187 #ifndef OPENSSL_NO_POSIX_IO
192 #if defined(S_ISBLK) && defined(S_ISCHR)
193 if (S_ISBLK(sb.st_mode) || S_ISCHR(sb.st_mode)) {
194 /* this file is a device. we don't write back to it.
195 * we "succeed" on the assumption this is some sort
196 * of random device. Otherwise attempting to write to
197 * and chmod the device causes problems.
205 #if defined(O_CREAT) && !defined(OPENSSL_NO_POSIX_IO) && !defined(OPENSSL_SYS_VMS)
210 /* chmod(..., 0600) is too late to protect the file,
211 * permissions should be restrictive from the start */
212 int fd = open(file, O_WRONLY|O_CREAT|O_BINARY, 0600);
214 out = fdopen(fd, "wb");
218 #ifdef OPENSSL_SYS_VMS
219 /* VMS NOTE: Prior versions of this routine created a _new_
220 * version of the rand file for each call into this routine, then
221 * deleted all existing versions named ;-1, and finally renamed
222 * the current version as ';1'. Under concurrent usage, this
223 * resulted in an RMS race condition in rename() which could
224 * orphan files (see vms message help for RMS$_REENT). With the
225 * fopen() calls below, openssl/VMS now shares the top-level
226 * version of the rand file. Note that there may still be
227 * conditions where the top-level rand file is locked. If so, this
228 * code will then create a new version of the rand file. Without
229 * the delete and rename code, this can result in ascending file
230 * versions that stop at version 32767, and this routine will then
231 * return an error. The remedy for this is to recode the calling
232 * application to avoid concurrent use of the rand file, or
233 * synchronize usage at the application level. Also consider
234 * whether or not you NEED a persistent rand file in a concurrent
238 out = vms_fopen(file,"rb+",VMS_OPEN_ATTRS);
240 out = vms_fopen(file,"wb",VMS_OPEN_ATTRS);
243 out = fopen(file,"wb");
245 if (out == NULL) goto err;
253 i=(n > BUFSIZE)?BUFSIZE:n;
255 if (RAND_bytes(buf,i) <= 0)
257 i=fwrite(buf,1,i,out);
268 OPENSSL_cleanse(buf,BUFSIZE);
270 return (rand_err ? -1 : ret);
273 const char *RAND_file_name(char *buf, size_t size)
280 if (OPENSSL_issetugid() == 0)
281 s=getenv("RANDFILE");
282 if (s != NULL && *s && strlen(s) + 1 < size)
284 if (BUF_strlcpy(buf,s,size) >= size)
289 if (OPENSSL_issetugid() == 0)
297 if (s && *s && strlen(s)+strlen(RFILE)+2 < size)
299 BUF_strlcpy(buf,s,size);
300 #ifndef OPENSSL_SYS_VMS
301 BUF_strlcat(buf,"/",size);
303 BUF_strlcat(buf,RFILE,size);
306 buf[0] = '\0'; /* no file name */
310 /* given that all random loads just fail if the file can't be
311 * seen on a stat, we stat the file we're returning, if it
312 * fails, use /dev/arandom instead. this allows the user to
313 * use their own source for good random data, but defaults
314 * to something hopefully decent if that isn't available.
318 if (BUF_strlcpy(buf,"/dev/arandom",size) >= size) {
321 if (stat(buf,&sb) == -1)
322 if (BUF_strlcpy(buf,"/dev/arandom",size) >= size) {