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 #define _XOPEN_SOURCE 500
68 #include <openssl/crypto.h>
69 #include <openssl/rand.h>
70 #include <openssl/buffer.h>
72 #ifdef OPENSSL_SYS_VMS
75 #ifndef NO_SYS_TYPES_H
76 # include <sys/types.h>
81 # include <sys/stat.h>
86 #define RAND_DATA 1024
88 /* #define RFILE ".rnd" - defined in ../../e_os.h */
90 /* Note that these functions are intended for seed files only.
91 * Entropy devices and EGD sockets are handled in rand_unix.c */
93 int RAND_load_file(const char *file, long bytes)
95 /* If bytes >= 0, read up to 'bytes' bytes.
96 * if bytes == -1, read complete file. */
98 MS_STATIC unsigned char buf[BUFSIZE];
103 if (file == NULL) return(0);
105 if (stat(file,&sb) < 0) return(0);
106 RAND_add(&sb,sizeof(sb),0.0);
107 if (bytes == 0) return(ret);
110 if (in == NULL) goto err;
111 #if defined(S_IFBLK) && defined(S_IFCHR)
112 if (sb.st_mode & (S_IFBLK | S_IFCHR)) {
113 /* this file is a device. we don't want read an infinite number
114 * of bytes from a random device, nor do we want to use buffered
115 * I/O because we will waste system entropy.
117 bytes = (bytes == -1) ? 2048 : bytes; /* ok, is 2048 enough? */
118 setvbuf(in, NULL, _IONBF, 0); /* don't do buffered reads */
124 n = (bytes < BUFSIZE)?(int)bytes:BUFSIZE;
130 RAND_add(buf,i,(double)i);
132 /* even if n != i, use the full array */
133 RAND_add(buf,n,(double)i);
139 if (bytes <= 0) break;
143 OPENSSL_cleanse(buf,BUFSIZE);
148 int RAND_write_file(const char *file)
150 unsigned char buf[BUFSIZE];
151 int i,ret=0,rand_err=0;
158 #if defined(S_IFBLK) && defined(S_IFCHR)
159 if (sb.st_mode & (S_IFBLK | S_IFCHR)) {
160 /* this file is a device. we don't write back to it.
161 * we "succeed" on the assumption this is some sort
162 * of random device. Otherwise attempting to write to
163 * and chmod the device causes problems.
170 #if defined(O_CREAT) && !defined(OPENSSL_SYS_WIN32)
172 /* For some reason Win32 can't write to files created this way */
174 /* chmod(..., 0600) is too late to protect the file,
175 * permissions should be restrictive from the start */
176 int fd = open(file, O_CREAT, 0600);
178 out = fdopen(fd, "wb");
182 out = fopen(file,"wb");
183 if (out == NULL) goto err;
191 i=(n > BUFSIZE)?BUFSIZE:n;
193 if (RAND_bytes(buf,i) <= 0)
195 i=fwrite(buf,1,i,out);
204 #ifdef OPENSSL_SYS_VMS
205 /* Try to delete older versions of the file, until there aren't
210 tmpf = OPENSSL_malloc(strlen(file) + 4); /* to add ";-1" and a nul */
215 while(delete(tmpf) == 0)
217 rename(file,";1"); /* Make sure it's version 1, or we
218 will reach the limit (32767) at
222 #endif /* OPENSSL_SYS_VMS */
225 OPENSSL_cleanse(buf,BUFSIZE);
227 return (rand_err ? -1 : ret);
230 const char *RAND_file_name(char *buf, size_t size)
238 if (OPENSSL_issetugid() == 0)
239 s=getenv("RANDFILE");
240 if (s != NULL && *s && strlen(s) + 1 < size)
242 if (BUF_strlcpy(buf,s,size) >= size)
247 if (OPENSSL_issetugid() == 0)
255 if (s && *s && strlen(s)+strlen(RFILE)+2 < size)
257 BUF_strlcpy(buf,s,size);
258 #ifndef OPENSSL_SYS_VMS
259 BUF_strlcat(buf,"/",size);
261 BUF_strlcat(buf,RFILE,size);
265 buf[0] = '\0'; /* no file name */
269 /* given that all random loads just fail if the file can't be
270 * seen on a stat, we stat the file we're returning, if it
271 * fails, use /dev/arandom instead. this allows the user to
272 * use their own source for good random data, but defaults
273 * to something hopefully decent if that isn't available.
277 if (BUF_strlcpy(buf,"/dev/arandom",size) >= size) {
280 if (stat(buf,&sb) == -1)
281 if (BUF_strlcpy(buf,"/dev/arandom",size) >= size) {