1 /* 2 * Copyright (c) 1997-1999 Kungliga Tekniska H�gskolan 3 * (Royal Institute of Technology, Stockholm, Sweden). 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 * 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 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 * 3. Neither the name of the Institute nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #include "kadm5_locl.h" 35 36 RCSID("$Id: password_quality.c,v 1.3 1999/12/02 17:05:06 joda Exp $"); 37 38 #ifdef HAVE_DLFCN_H 39 #include <dlfcn.h> 40 #endif 41 42 static const char * 43 simple_passwd_quality (krb5_context context, 44 krb5_principal principal, 45 krb5_data *pwd) 46 { 47 if (pwd->length < 6) 48 return "Password too short"; 49 else 50 return NULL; 51 } 52 53 typedef const char* (*passwd_quality_check_func)(krb5_context, 54 krb5_principal, 55 krb5_data*); 56 57 static passwd_quality_check_func passwd_quality_check = simple_passwd_quality; 58 59 #ifdef HAVE_DLOPEN 60 extern const char *check_library; 61 extern const char *check_function; 62 63 #define PASSWD_VERSION 0 64 65 #endif 66 67 /* 68 * setup the password quality hook 69 */ 70 71 void 72 kadm5_setup_passwd_quality_check(krb5_context context, 73 const char *check_library, 74 const char *check_function) 75 { 76 #ifdef HAVE_DLOPEN 77 void *handle; 78 void *sym; 79 int *version; 80 int flags; 81 const char *tmp; 82 83 #ifdef RTLD_NOW 84 flags = RTLD_NOW; 85 #else 86 flags = 0; 87 #endif 88 89 if(check_library == NULL) { 90 tmp = krb5_config_get_string(context, NULL, 91 "password_quality", 92 "check_library", 93 NULL); 94 if(tmp != NULL) 95 check_library = tmp; 96 } 97 if(check_function == NULL) { 98 tmp = krb5_config_get_string(context, NULL, 99 "password_quality", 100 "check_function", 101 NULL); 102 if(tmp != NULL) 103 check_function = tmp; 104 } 105 if(check_library != NULL && check_function == NULL) 106 check_function = "passwd_check"; 107 108 if(check_library == NULL) 109 return; 110 handle = dlopen(check_library, flags); 111 if(handle == NULL) { 112 krb5_warnx(context, "failed to open `%s'", check_library); 113 return; 114 } 115 version = dlsym(handle, "version"); 116 if(version == NULL) { 117 krb5_warnx(context, 118 "didn't find `version' symbol in `%s'", check_library); 119 dlclose(handle); 120 return; 121 } 122 if(*version != PASSWD_VERSION) { 123 krb5_warnx(context, 124 "version of loaded library is %d (expected %d)", 125 *version, PASSWD_VERSION); 126 dlclose(handle); 127 return; 128 } 129 sym = dlsym(handle, check_function); 130 if(sym == NULL) { 131 krb5_warnx(context, 132 "didn't find `%s' symbol in `%s'", 133 check_function, check_library); 134 dlclose(handle); 135 return; 136 } 137 passwd_quality_check = (passwd_quality_check_func) sym; 138 #endif /* HAVE_DLOPEN */ 139 } 140 141 const char * 142 kadm5_check_password_quality (krb5_context context, 143 krb5_principal principal, 144 krb5_data *pwd_data) 145 { 146 return (*passwd_quality_check) (context, principal, pwd_data); 147 } 148