1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 1999 Mark Murray 5 * Copyright (c) 2014 Dag-Erling Smørgrav 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY MARK MURRAY AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL MARK MURRAY OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30 #include <sys/types.h> 31 32 #include <string.h> 33 #include <unistd.h> 34 35 #include "crypt.h" 36 37 /* 38 * List of supported crypt(3) formats. 39 * 40 * The default algorithm is the last entry in the list (second-to-last 41 * array element since the last is a sentinel). The reason for placing 42 * the default last rather than first is that DES needs to be at the 43 * bottom for the algorithm guessing logic in crypt(3) to work correctly, 44 * and it needs to be the default for backward compatibility. 45 */ 46 static const struct crypt_format { 47 const char *name; 48 int (*func)(const char *, const char *, char *); 49 const char *magic; 50 } crypt_formats[] = { 51 { "md5", crypt_md5, "$1$" }, 52 #ifdef HAS_BLOWFISH 53 { "blf", crypt_blowfish, "$2" }, 54 #endif 55 { "nth", crypt_nthash, "$3$" }, 56 { "sha256", crypt_sha256, "$5$" }, 57 { "sha512", crypt_sha512, "$6$" }, 58 #ifdef HAS_DES 59 { "des", crypt_des, "_" }, 60 #endif 61 62 /* sentinel */ 63 { NULL, NULL, NULL } 64 }; 65 66 static const struct crypt_format *crypt_format = 67 &crypt_formats[(sizeof crypt_formats / sizeof *crypt_formats) - 2]; 68 69 #define DES_SALT_ALPHABET \ 70 "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz" 71 72 /* 73 * Returns the name of the currently selected format. 74 */ 75 const char * 76 crypt_get_format(void) 77 { 78 79 return (crypt_format->name); 80 } 81 82 /* 83 * Selects the format to use for subsequent crypt(3) invocations. 84 */ 85 int 86 crypt_set_format(const char *format) 87 { 88 const struct crypt_format *cf; 89 90 for (cf = crypt_formats; cf->name != NULL; ++cf) { 91 if (strcasecmp(cf->name, format) == 0) { 92 crypt_format = cf; 93 return (1); 94 } 95 } 96 return (0); 97 } 98 99 /* 100 * Hash the given password with the given salt. If the salt begins with a 101 * magic string (e.g. "$6$" for sha512), the corresponding format is used; 102 * otherwise, the currently selected format is used. 103 */ 104 char * 105 crypt_r(const char *passwd, const char *salt, struct crypt_data *data) 106 { 107 const struct crypt_format *cf; 108 int (*func)(const char *, const char *, char *); 109 #ifdef HAS_DES 110 int len; 111 #endif 112 113 for (cf = crypt_formats; cf->name != NULL; ++cf) 114 if (cf->magic != NULL && strstr(salt, cf->magic) == salt) { 115 func = cf->func; 116 goto match; 117 } 118 #ifdef HAS_DES 119 len = strlen(salt); 120 if ((len == 13 || len == 2) && strspn(salt, DES_SALT_ALPHABET) == len) { 121 func = crypt_des; 122 goto match; 123 } 124 #endif 125 func = crypt_format->func; 126 match: 127 if (func(passwd, salt, data->__buf) != 0) 128 return (NULL); 129 return (data->__buf); 130 } 131 132 char * 133 crypt(const char *passwd, const char *salt) 134 { 135 static struct crypt_data data; 136 137 return (crypt_r(passwd, salt, &data)); 138 } 139