1 /* 2 * Copyright (c) 1999 - 2000 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 "krb5_locl.h" 35 36 RCSID("$Id: expand_hostname.c,v 1.9 2000/02/23 03:12:07 assar Exp $"); 37 38 static krb5_error_code 39 copy_hostname(krb5_context context, 40 const char *orig_hostname, 41 char **new_hostname) 42 { 43 *new_hostname = strdup (orig_hostname); 44 if (*new_hostname == NULL) 45 return ENOMEM; 46 strlwr (*new_hostname); 47 return 0; 48 } 49 50 /* 51 * Try to make `orig_hostname' into a more canonical one in the newly 52 * allocated space returned in `new_hostname'. 53 */ 54 55 krb5_error_code 56 krb5_expand_hostname (krb5_context context, 57 const char *orig_hostname, 58 char **new_hostname) 59 { 60 struct addrinfo *ai, *a, hints; 61 int error; 62 63 memset (&hints, 0, sizeof(hints)); 64 hints.ai_flags = AI_CANONNAME; 65 66 error = getaddrinfo (orig_hostname, NULL, &hints, &ai); 67 if (error) 68 return copy_hostname (context, orig_hostname, new_hostname); 69 for (a = ai; a != NULL; a = a->ai_next) { 70 if (a->ai_canonname != NULL) { 71 *new_hostname = strdup (a->ai_canonname); 72 freeaddrinfo (ai); 73 if (*new_hostname == NULL) 74 return ENOMEM; 75 else 76 return 0; 77 } 78 } 79 freeaddrinfo (ai); 80 return copy_hostname (context, orig_hostname, new_hostname); 81 } 82 83 /* 84 * handle the case of the hostname being unresolvable and thus identical 85 */ 86 87 static krb5_error_code 88 vanilla_hostname (krb5_context context, 89 const char *orig_hostname, 90 char **new_hostname, 91 char ***realms) 92 { 93 krb5_error_code ret; 94 95 ret = copy_hostname (context, orig_hostname, new_hostname); 96 if (ret) 97 return ret; 98 strlwr (*new_hostname); 99 100 ret = krb5_get_host_realm (context, *new_hostname, realms); 101 if (ret) { 102 free (*new_hostname); 103 return ret; 104 } 105 return 0; 106 } 107 108 /* 109 * expand `hostname' to a name we believe to be a hostname in newly 110 * allocated space in `host' and return realms in `realms'. 111 */ 112 113 krb5_error_code 114 krb5_expand_hostname_realms (krb5_context context, 115 const char *orig_hostname, 116 char **new_hostname, 117 char ***realms) 118 { 119 struct addrinfo *ai, *a, hints; 120 int error; 121 krb5_error_code ret = 0; 122 123 memset (&hints, 0, sizeof(hints)); 124 hints.ai_flags = AI_CANONNAME; 125 126 error = getaddrinfo (orig_hostname, NULL, &hints, &ai); 127 if (error) 128 return vanilla_hostname (context, orig_hostname, new_hostname, 129 realms); 130 131 for (a = ai; a != NULL; a = a->ai_next) { 132 if (a->ai_canonname != NULL) { 133 ret = copy_hostname (context, a->ai_canonname, new_hostname); 134 if (ret) { 135 freeaddrinfo (ai); 136 return ret; 137 } 138 strlwr (*new_hostname); 139 ret = krb5_get_host_realm (context, *new_hostname, realms); 140 if (ret == 0) { 141 freeaddrinfo (ai); 142 return 0; 143 } 144 free (*new_hostname); 145 } 146 } 147 return vanilla_hostname (context, orig_hostname, new_hostname, realms); 148 } 149