1 /* 2 * Copyright (c) 1997 - 2002 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: get_addrs.c,v 1.44 2002/08/16 20:50:15 joda Exp $"); 37 38 #ifdef __osf__ 39 /* hate */ 40 struct rtentry; 41 struct mbuf; 42 #endif 43 #ifdef HAVE_NET_IF_H 44 #include <net/if.h> 45 #endif 46 #include <ifaddrs.h> 47 48 static krb5_error_code 49 gethostname_fallback (krb5_context context, krb5_addresses *res) 50 { 51 krb5_error_code ret; 52 char hostname[MAXHOSTNAMELEN]; 53 struct hostent *hostent; 54 55 if (gethostname (hostname, sizeof(hostname))) { 56 ret = errno; 57 krb5_set_error_string (context, "gethostname: %s", strerror(ret)); 58 return ret; 59 } 60 hostent = roken_gethostbyname (hostname); 61 if (hostent == NULL) { 62 ret = errno; 63 krb5_set_error_string (context, "gethostbyname %s: %s", 64 hostname, strerror(ret)); 65 return ret; 66 } 67 res->len = 1; 68 res->val = malloc (sizeof(*res->val)); 69 if (res->val == NULL) { 70 krb5_set_error_string(context, "malloc: out of memory"); 71 return ENOMEM; 72 } 73 res->val[0].addr_type = hostent->h_addrtype; 74 res->val[0].address.data = NULL; 75 res->val[0].address.length = 0; 76 ret = krb5_data_copy (&res->val[0].address, 77 hostent->h_addr, 78 hostent->h_length); 79 if (ret) { 80 free (res->val); 81 return ret; 82 } 83 return 0; 84 } 85 86 enum { 87 LOOP = 1, /* do include loopback interfaces */ 88 LOOP_IF_NONE = 2, /* include loopback if no other if's */ 89 EXTRA_ADDRESSES = 4, /* include extra addresses */ 90 SCAN_INTERFACES = 8 /* scan interfaces for addresses */ 91 }; 92 93 /* 94 * Try to figure out the addresses of all configured interfaces with a 95 * lot of magic ioctls. 96 */ 97 98 static krb5_error_code 99 find_all_addresses (krb5_context context, krb5_addresses *res, int flags) 100 { 101 struct sockaddr sa_zero; 102 struct ifaddrs *ifa0, *ifa; 103 krb5_error_code ret = ENXIO; 104 int num, idx; 105 krb5_addresses ignore_addresses; 106 107 res->val = NULL; 108 109 if (getifaddrs(&ifa0) == -1) { 110 ret = errno; 111 krb5_set_error_string(context, "getifaddrs: %s", strerror(ret)); 112 return (ret); 113 } 114 115 memset(&sa_zero, 0, sizeof(sa_zero)); 116 117 /* First, count all the ifaddrs. */ 118 for (ifa = ifa0, num = 0; ifa != NULL; ifa = ifa->ifa_next, num++) 119 /* nothing */; 120 121 if (num == 0) { 122 freeifaddrs(ifa0); 123 krb5_set_error_string(context, "no addresses found"); 124 return (ENXIO); 125 } 126 127 if (flags & EXTRA_ADDRESSES) { 128 /* we'll remove the addresses we don't care about */ 129 ret = krb5_get_ignore_addresses(context, &ignore_addresses); 130 if(ret) 131 return ret; 132 } 133 134 /* Allocate storage for them. */ 135 res->val = calloc(num, sizeof(*res->val)); 136 if (res->val == NULL) { 137 krb5_free_addresses(context, &ignore_addresses); 138 freeifaddrs(ifa0); 139 krb5_set_error_string (context, "malloc: out of memory"); 140 return (ENOMEM); 141 } 142 143 /* Now traverse the list. */ 144 for (ifa = ifa0, idx = 0; ifa != NULL; ifa = ifa->ifa_next) { 145 if ((ifa->ifa_flags & IFF_UP) == 0) 146 continue; 147 if (memcmp(ifa->ifa_addr, &sa_zero, sizeof(sa_zero)) == 0) 148 continue; 149 if (krb5_sockaddr_uninteresting(ifa->ifa_addr)) 150 continue; 151 if ((ifa->ifa_flags & IFF_LOOPBACK) != 0) { 152 /* We'll deal with the LOOP_IF_NONE case later. */ 153 if ((flags & LOOP) == 0) 154 continue; 155 } 156 157 ret = krb5_sockaddr2address(context, ifa->ifa_addr, &res->val[idx]); 158 if (ret) { 159 /* 160 * The most likely error here is going to be "Program 161 * lacks support for address type". This is no big 162 * deal -- just continue, and we'll listen on the 163 * addresses who's type we *do* support. 164 */ 165 continue; 166 } 167 /* possibly skip this address? */ 168 if((flags & EXTRA_ADDRESSES) && 169 krb5_address_search(context, &res->val[idx], &ignore_addresses)) { 170 krb5_free_address(context, &res->val[idx]); 171 flags &= ~LOOP_IF_NONE; /* we actually found an address, 172 so don't add any loop-back 173 addresses */ 174 continue; 175 } 176 177 idx++; 178 } 179 180 /* 181 * If no addresses were found, and LOOP_IF_NONE is set, then find 182 * the loopback addresses and add them to our list. 183 */ 184 if ((flags & LOOP_IF_NONE) != 0 && idx == 0) { 185 for (ifa = ifa0; ifa != NULL; ifa = ifa->ifa_next) { 186 if ((ifa->ifa_flags & IFF_UP) == 0) 187 continue; 188 if (memcmp(ifa->ifa_addr, &sa_zero, sizeof(sa_zero)) == 0) 189 continue; 190 if (krb5_sockaddr_uninteresting(ifa->ifa_addr)) 191 continue; 192 193 if ((ifa->ifa_flags & IFF_LOOPBACK) != 0) { 194 ret = krb5_sockaddr2address(context, 195 ifa->ifa_addr, &res->val[idx]); 196 if (ret) { 197 /* 198 * See comment above. 199 */ 200 continue; 201 } 202 if((flags & EXTRA_ADDRESSES) && 203 krb5_address_search(context, &res->val[idx], 204 &ignore_addresses)) { 205 krb5_free_address(context, &res->val[idx]); 206 continue; 207 } 208 idx++; 209 } 210 } 211 } 212 213 if (flags & EXTRA_ADDRESSES) 214 krb5_free_addresses(context, &ignore_addresses); 215 freeifaddrs(ifa0); 216 if (ret) 217 free(res->val); 218 else 219 res->len = idx; /* Now a count. */ 220 return (ret); 221 } 222 223 static krb5_error_code 224 get_addrs_int (krb5_context context, krb5_addresses *res, int flags) 225 { 226 krb5_error_code ret = -1; 227 228 if (flags & SCAN_INTERFACES) { 229 ret = find_all_addresses (context, res, flags); 230 if(ret || res->len == 0) 231 ret = gethostname_fallback (context, res); 232 } else { 233 res->len = 0; 234 res->val = NULL; 235 ret = 0; 236 } 237 238 if(ret == 0 && (flags & EXTRA_ADDRESSES)) { 239 krb5_addresses a; 240 /* append user specified addresses */ 241 ret = krb5_get_extra_addresses(context, &a); 242 if(ret) { 243 krb5_free_addresses(context, res); 244 return ret; 245 } 246 ret = krb5_append_addresses(context, res, &a); 247 if(ret) { 248 krb5_free_addresses(context, res); 249 return ret; 250 } 251 krb5_free_addresses(context, &a); 252 } 253 if(res->len == 0) { 254 free(res->val); 255 res->val = NULL; 256 } 257 return ret; 258 } 259 260 /* 261 * Try to get all addresses, but return the one corresponding to 262 * `hostname' if we fail. 263 * 264 * Only include loopback address if there are no other. 265 */ 266 267 krb5_error_code 268 krb5_get_all_client_addrs (krb5_context context, krb5_addresses *res) 269 { 270 int flags = LOOP_IF_NONE | EXTRA_ADDRESSES; 271 272 if (context->scan_interfaces) 273 flags |= SCAN_INTERFACES; 274 275 return get_addrs_int (context, res, flags); 276 } 277 278 /* 279 * Try to get all local addresses that a server should listen to. 280 * If that fails, we return the address corresponding to `hostname'. 281 */ 282 283 krb5_error_code 284 krb5_get_all_server_addrs (krb5_context context, krb5_addresses *res) 285 { 286 return get_addrs_int (context, res, LOOP | SCAN_INTERFACES); 287 } 288