1 /* $OpenBSD: randfile.c,v 1.44 2023/07/07 19:37:54 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 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 89 int 90 RAND_write_file(const char *file) 91 { 92 unsigned char buf[BUFSIZE]; 93 int i, ret = 0; 94 FILE *out = NULL; 95 int n, fd; 96 struct stat sb; 97 98 /* 99 * If this file is a device, avoid opening it. 100 * XXX TOCTOU 101 */ 102 if (stat(file, &sb) != -1 && 103 (S_ISBLK(sb.st_mode) || S_ISCHR(sb.st_mode))) { 104 return (1); 105 } 106 107 fd = open(file, O_WRONLY|O_CREAT, 0600); 108 if (fd == -1) 109 return (1); 110 out = fdopen(fd, "wb"); 111 112 if (out == NULL) { 113 close(fd); 114 return (1); 115 } 116 117 n = RAND_DATA; 118 for (;;) { 119 i = (n > BUFSIZE) ? BUFSIZE : n; 120 n -= BUFSIZE; 121 arc4random_buf(buf, i); 122 i = fwrite(buf, 1, i, out); 123 if (i <= 0) { 124 ret = 0; 125 break; 126 } 127 ret += i; 128 if (n <= 0) 129 break; 130 } 131 132 fclose(out); 133 explicit_bzero(buf, BUFSIZE); 134 return ret; 135 } 136 137 const char * 138 RAND_file_name(char * buf, size_t size) 139 { 140 if (strlcpy(buf, "/dev/urandom", size) >= size) 141 return (NULL); 142 return buf; 143 } 144