1 /* $OpenBSD: randfile.c,v 1.45 2024/04/10 14:53:01 beck Exp $ */
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 <unistd.h>
63 #include <string.h>
64
65 #include <openssl/crypto.h>
66 #include <openssl/rand.h>
67 #include <openssl/buffer.h>
68
69 #include <sys/types.h>
70 #include <sys/stat.h>
71 #include <fcntl.h>
72
73 #undef BUFSIZE
74 #define BUFSIZE 1024
75 #define RAND_DATA 1024
76
77 /* Note that these functions should not be used. */
78
79 int
RAND_load_file(const char * file,long bytes)80 RAND_load_file(const char *file, long bytes)
81 {
82 /* the "whole" file */
83 if (bytes == -1)
84 return 123456;
85 else
86 return bytes;
87 }
88 LCRYPTO_ALIAS(RAND_load_file);
89
90 int
RAND_write_file(const char * file)91 RAND_write_file(const char *file)
92 {
93 unsigned char buf[BUFSIZE];
94 int i, ret = 0;
95 FILE *out = NULL;
96 int n, fd;
97 struct stat sb;
98
99 /*
100 * If this file is a device, avoid opening it.
101 * XXX TOCTOU
102 */
103 if (stat(file, &sb) != -1 &&
104 (S_ISBLK(sb.st_mode) || S_ISCHR(sb.st_mode))) {
105 return (1);
106 }
107
108 fd = open(file, O_WRONLY|O_CREAT, 0600);
109 if (fd == -1)
110 return (1);
111 out = fdopen(fd, "wb");
112
113 if (out == NULL) {
114 close(fd);
115 return (1);
116 }
117
118 n = RAND_DATA;
119 for (;;) {
120 i = (n > BUFSIZE) ? BUFSIZE : n;
121 n -= BUFSIZE;
122 arc4random_buf(buf, i);
123 i = fwrite(buf, 1, i, out);
124 if (i <= 0) {
125 ret = 0;
126 break;
127 }
128 ret += i;
129 if (n <= 0)
130 break;
131 }
132
133 fclose(out);
134 explicit_bzero(buf, BUFSIZE);
135 return ret;
136 }
137 LCRYPTO_ALIAS(RAND_write_file);
138
139 const char *
RAND_file_name(char * buf,size_t size)140 RAND_file_name(char * buf, size_t size)
141 {
142 if (strlcpy(buf, "/dev/urandom", size) >= size)
143 return (NULL);
144 return buf;
145 }
146 LCRYPTO_ALIAS(RAND_file_name);
147