1/* $NetBSD: expand_hostname.c,v 1.1.1.1 2011/04/13 18:15:33 elric Exp $ */ 2 3/* 4 * Copyright (c) 1999 - 2001 Kungliga Tekniska Högskolan 5 * (Royal Institute of Technology, Stockholm, Sweden). 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 * 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * 3. Neither the name of the Institute nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36#include "krb5_locl.h" 37 38static krb5_error_code 39copy_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_message(context, ENOMEM, 46 N_("malloc: out of memory", "")); 47 return ENOMEM; 48 } 49 strlwr (*new_hostname); 50 return 0; 51} 52 53/** 54 * krb5_expand_hostname() tries to make orig_hostname into a more 55 * canonical one in the newly allocated space returned in 56 * new_hostname. 57 58 * @param context a Keberos context 59 * @param orig_hostname hostname to canonicalise. 60 * @param new_hostname output hostname, caller must free hostname with 61 * krb5_xfree(). 62 * 63 * @return Return an error code or 0, see krb5_get_error_message(). 64 * 65 * @ingroup krb5_support 66 */ 67 68KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL 69krb5_expand_hostname (krb5_context context, 70 const char *orig_hostname, 71 char **new_hostname) 72{ 73 struct addrinfo *ai, *a, hints; 74 int error; 75 76 if ((context->flags & KRB5_CTX_F_DNS_CANONICALIZE_HOSTNAME) == 0) 77 return copy_hostname (context, orig_hostname, new_hostname); 78 79 memset (&hints, 0, sizeof(hints)); 80 hints.ai_flags = AI_CANONNAME; 81 82 error = getaddrinfo (orig_hostname, NULL, &hints, &ai); 83 if (error) 84 return copy_hostname (context, orig_hostname, new_hostname); 85 for (a = ai; a != NULL; a = a->ai_next) { 86 if (a->ai_canonname != NULL) { 87 *new_hostname = strdup (a->ai_canonname); 88 freeaddrinfo (ai); 89 if (*new_hostname == NULL) { 90 krb5_set_error_message(context, ENOMEM, 91 N_("malloc: out of memory", "")); 92 return ENOMEM; 93 } else { 94 return 0; 95 } 96 } 97 } 98 freeaddrinfo (ai); 99 return copy_hostname (context, orig_hostname, new_hostname); 100} 101 102/* 103 * handle the case of the hostname being unresolvable and thus identical 104 */ 105 106static krb5_error_code 107vanilla_hostname (krb5_context context, 108 const char *orig_hostname, 109 char **new_hostname, 110 char ***realms) 111{ 112 krb5_error_code ret; 113 114 ret = copy_hostname (context, orig_hostname, new_hostname); 115 if (ret) 116 return ret; 117 strlwr (*new_hostname); 118 119 ret = krb5_get_host_realm (context, *new_hostname, realms); 120 if (ret) { 121 free (*new_hostname); 122 return ret; 123 } 124 return 0; 125} 126 127/** 128 * krb5_expand_hostname_realms() expands orig_hostname to a name we 129 * believe to be a hostname in newly allocated space in new_hostname 130 * and return the realms new_hostname is believed to belong to in 131 * realms. 132 * 133 * @param context a Keberos context 134 * @param orig_hostname hostname to canonicalise. 135 * @param new_hostname output hostname, caller must free hostname with 136 * krb5_xfree(). 137 * @param realms output possible realms, is an array that is terminated 138 * with NULL. Caller must free with krb5_free_host_realm(). 139 * 140 * @return Return an error code or 0, see krb5_get_error_message(). 141 * 142 * @ingroup krb5_support 143 */ 144 145KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL 146krb5_expand_hostname_realms (krb5_context context, 147 const char *orig_hostname, 148 char **new_hostname, 149 char ***realms) 150{ 151 struct addrinfo *ai, *a, hints; 152 int error; 153 krb5_error_code ret = 0; 154 155 if ((context->flags & KRB5_CTX_F_DNS_CANONICALIZE_HOSTNAME) == 0) 156 return vanilla_hostname (context, orig_hostname, new_hostname, 157 realms); 158 159 memset (&hints, 0, sizeof(hints)); 160 hints.ai_flags = AI_CANONNAME; 161 162 error = getaddrinfo (orig_hostname, NULL, &hints, &ai); 163 if (error) 164 return vanilla_hostname (context, orig_hostname, new_hostname, 165 realms); 166 167 for (a = ai; a != NULL; a = a->ai_next) { 168 if (a->ai_canonname != NULL) { 169 ret = copy_hostname (context, a->ai_canonname, new_hostname); 170 if (ret) { 171 freeaddrinfo (ai); 172 return ret; 173 } 174 strlwr (*new_hostname); 175 ret = krb5_get_host_realm (context, *new_hostname, realms); 176 if (ret == 0) { 177 freeaddrinfo (ai); 178 return 0; 179 } 180 free (*new_hostname); 181 } 182 } 183 freeaddrinfo(ai); 184 return vanilla_hostname (context, orig_hostname, new_hostname, realms); 185} 186