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