1 /* 2 * Copyright (c) 1999 - 2001 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 1.11 2001/09/18 09:35:47 joda 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 krb5_set_error_string(context, "malloc: out of memory"); 46 return ENOMEM; 47 } 48 strlwr (*new_hostname); 49 return 0; 50 } 51 52 /* 53 * Try to make `orig_hostname' into a more canonical one in the newly 54 * allocated space returned in `new_hostname'. 55 */ 56 57 krb5_error_code 58 krb5_expand_hostname (krb5_context context, 59 const char *orig_hostname, 60 char **new_hostname) 61 { 62 struct addrinfo *ai, *a, hints; 63 int error; 64 65 memset (&hints, 0, sizeof(hints)); 66 hints.ai_flags = AI_CANONNAME; 67 68 error = getaddrinfo (orig_hostname, NULL, &hints, &ai); 69 if (error) 70 return copy_hostname (context, orig_hostname, new_hostname); 71 for (a = ai; a != NULL; a = a->ai_next) { 72 if (a->ai_canonname != NULL) { 73 *new_hostname = strdup (a->ai_canonname); 74 freeaddrinfo (ai); 75 if (*new_hostname == NULL) { 76 krb5_set_error_string(context, "malloc: out of memory"); 77 return ENOMEM; 78 } else { 79 return 0; 80 } 81 } 82 } 83 freeaddrinfo (ai); 84 return copy_hostname (context, orig_hostname, new_hostname); 85 } 86 87 /* 88 * handle the case of the hostname being unresolvable and thus identical 89 */ 90 91 static krb5_error_code 92 vanilla_hostname (krb5_context context, 93 const char *orig_hostname, 94 char **new_hostname, 95 char ***realms) 96 { 97 krb5_error_code ret; 98 99 ret = copy_hostname (context, orig_hostname, new_hostname); 100 if (ret) 101 return ret; 102 strlwr (*new_hostname); 103 104 ret = krb5_get_host_realm (context, *new_hostname, realms); 105 if (ret) { 106 free (*new_hostname); 107 return ret; 108 } 109 return 0; 110 } 111 112 /* 113 * expand `hostname' to a name we believe to be a hostname in newly 114 * allocated space in `host' and return realms in `realms'. 115 */ 116 117 krb5_error_code 118 krb5_expand_hostname_realms (krb5_context context, 119 const char *orig_hostname, 120 char **new_hostname, 121 char ***realms) 122 { 123 struct addrinfo *ai, *a, hints; 124 int error; 125 krb5_error_code ret = 0; 126 127 memset (&hints, 0, sizeof(hints)); 128 hints.ai_flags = AI_CANONNAME; 129 130 error = getaddrinfo (orig_hostname, NULL, &hints, &ai); 131 if (error) 132 return vanilla_hostname (context, orig_hostname, new_hostname, 133 realms); 134 135 for (a = ai; a != NULL; a = a->ai_next) { 136 if (a->ai_canonname != NULL) { 137 ret = copy_hostname (context, a->ai_canonname, new_hostname); 138 if (ret) { 139 freeaddrinfo (ai); 140 return ret; 141 } 142 strlwr (*new_hostname); 143 ret = krb5_get_host_realm (context, *new_hostname, realms); 144 if (ret == 0) { 145 freeaddrinfo (ai); 146 return 0; 147 } 148 free (*new_hostname); 149 } 150 } 151 freeaddrinfo(ai); 152 return vanilla_hostname (context, orig_hostname, new_hostname, realms); 153 } 154