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>
89 # define fdopen _fdopen
94 #define RAND_DATA 1024
96 #ifdef OPENSSL_SYS_VMS
98 * This declaration is a nasty hack to get around vms' extension to fopen for
99 * passing in sharing options being disabled by our /STANDARD=ANSI89
101 static FILE *(*const vms_fopen
)(const char *, const char *, ...) =
102 (FILE *(*)(const char *, const char *, ...))fopen
;
103 # define VMS_OPEN_ATTRS "shr=get,put,upd,del","ctx=bin,stm","rfm=stm","rat=none","mrs=0"
106 /* #define RFILE ".rnd" - defined in ../../e_os.h */
109 * Note that these functions are intended for seed files only. Entropy
110 * devices and EGD sockets are handled in rand_unix.c
113 int RAND_load_file(const char *file
, long bytes
)
116 * If bytes >= 0, read up to 'bytes' bytes.
117 * if bytes == -1, read complete file.
120 MS_STATIC
unsigned char buf
[BUFSIZE
];
121 #ifndef OPENSSL_NO_POSIX_IO
130 #ifndef OPENSSL_NO_POSIX_IO
133 * struct stat can have padding and unused fields that may not be
134 * initialized in the call to stat(). We need to clear the entire
135 * structure before calling RAND_add() to avoid complaints from
136 * applications such as Valgrind.
138 memset(&sb
, 0, sizeof(sb
));
140 if (stat(file
, &sb
) < 0)
142 RAND_add(&sb
, sizeof(sb
), 0.0);
147 #ifdef OPENSSL_SYS_VMS
148 in
= vms_fopen(file
, "rb", VMS_OPEN_ATTRS
);
150 in
= fopen(file
, "rb");
154 #if defined(S_IFBLK) && defined(S_IFCHR) && !defined(OPENSSL_NO_POSIX_IO)
155 if (sb
.st_mode
& (S_IFBLK
| S_IFCHR
)) {
157 * this file is a device. we don't want read an infinite number of
158 * bytes from a random device, nor do we want to use buffered I/O
159 * because we will waste system entropy.
161 bytes
= (bytes
== -1) ? 2048 : bytes
; /* ok, is 2048 enough? */
162 # ifndef OPENSSL_NO_SETVBUF_IONBF
163 setvbuf(in
, NULL
, _IONBF
, 0); /* don't do buffered reads */
164 # endif /* ndef OPENSSL_NO_SETVBUF_IONBF */
169 n
= (bytes
< BUFSIZE
) ? (int)bytes
: BUFSIZE
;
172 i
= fread(buf
, 1, n
, in
);
176 RAND_add(buf
, i
, (double)i
);
178 /* even if n != i, use the full array */
179 RAND_add(buf
, n
, (double)i
);
189 OPENSSL_cleanse(buf
, BUFSIZE
);
194 int RAND_write_file(const char *file
)
196 unsigned char buf
[BUFSIZE
];
197 int i
, ret
= 0, rand_err
= 0;
200 #ifndef OPENSSL_NO_POSIX_IO
205 # if defined(S_ISBLK) && defined(S_ISCHR)
206 if (S_ISBLK(sb
.st_mode
) || S_ISCHR(sb
.st_mode
)) {
208 * this file is a device. we don't write back to it. we
209 * "succeed" on the assumption this is some sort of random
210 * device. Otherwise attempting to write to and chmod the device
219 #if defined(O_CREAT) && !defined(OPENSSL_NO_POSIX_IO) && !defined(OPENSSL_SYS_VMS)
225 * chmod(..., 0600) is too late to protect the file, permissions
226 * should be restrictive from the start
228 int fd
= open(file
, O_WRONLY
| O_CREAT
| O_BINARY
, 0600);
230 out
= fdopen(fd
, "wb");
234 #ifdef OPENSSL_SYS_VMS
236 * VMS NOTE: Prior versions of this routine created a _new_ version of
237 * the rand file for each call into this routine, then deleted all
238 * existing versions named ;-1, and finally renamed the current version
239 * as ';1'. Under concurrent usage, this resulted in an RMS race
240 * condition in rename() which could orphan files (see vms message help
241 * for RMS$_REENT). With the fopen() calls below, openssl/VMS now shares
242 * the top-level version of the rand file. Note that there may still be
243 * conditions where the top-level rand file is locked. If so, this code
244 * will then create a new version of the rand file. Without the delete
245 * and rename code, this can result in ascending file versions that stop
246 * at version 32767, and this routine will then return an error. The
247 * remedy for this is to recode the calling application to avoid
248 * concurrent use of the rand file, or synchronize usage at the
249 * application level. Also consider whether or not you NEED a persistent
250 * rand file in a concurrent use situation.
253 out
= vms_fopen(file
, "rb+", VMS_OPEN_ATTRS
);
255 out
= vms_fopen(file
, "wb", VMS_OPEN_ATTRS
);
258 out
= fopen(file
, "wb");
268 i
= (n
> BUFSIZE
) ? BUFSIZE
: n
;
270 if (RAND_bytes(buf
, i
) <= 0)
272 i
= fwrite(buf
, 1, i
, out
);
283 OPENSSL_cleanse(buf
, BUFSIZE
);
285 return (rand_err
? -1 : ret
);
288 const char *RAND_file_name(char *buf
, size_t size
)
295 if (OPENSSL_issetugid() == 0)
296 s
= getenv("RANDFILE");
297 if (s
!= NULL
&& *s
&& strlen(s
) + 1 < size
) {
298 if (BUF_strlcpy(buf
, s
, size
) >= size
)
301 if (OPENSSL_issetugid() == 0)
308 if (s
&& *s
&& strlen(s
) + strlen(RFILE
) + 2 < size
) {
309 BUF_strlcpy(buf
, s
, size
);
310 #ifndef OPENSSL_SYS_VMS
311 BUF_strlcat(buf
, "/", size
);
313 BUF_strlcat(buf
, RFILE
, size
);
315 buf
[0] = '\0'; /* no file name */
320 * given that all random loads just fail if the file can't be seen on a
321 * stat, we stat the file we're returning, if it fails, use /dev/arandom
322 * instead. this allows the user to use their own source for good random
323 * data, but defaults to something hopefully decent if that isn't
328 if (BUF_strlcpy(buf
, "/dev/arandom", size
) >= size
) {
331 if (stat(buf
, &sb
) == -1)
332 if (BUF_strlcpy(buf
, "/dev/arandom", size
) >= size
) {