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 1.45 2003/01/25 15:19:49 lha 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 (ifa->ifa_addr == NULL) 148 continue; 149 if (memcmp(ifa->ifa_addr, &sa_zero, sizeof(sa_zero)) == 0) 150 continue; 151 if (krb5_sockaddr_uninteresting(ifa->ifa_addr)) 152 continue; 153 if ((ifa->ifa_flags & IFF_LOOPBACK) != 0) { 154 /* We'll deal with the LOOP_IF_NONE case later. */ 155 if ((flags & LOOP) == 0) 156 continue; 157 } 158 159 ret = krb5_sockaddr2address(context, ifa->ifa_addr, &res->val[idx]); 160 if (ret) { 161 /* 162 * The most likely error here is going to be "Program 163 * lacks support for address type". This is no big 164 * deal -- just continue, and we'll listen on the 165 * addresses who's type we *do* support. 166 */ 167 continue; 168 } 169 /* possibly skip this address? */ 170 if((flags & EXTRA_ADDRESSES) && 171 krb5_address_search(context, &res->val[idx], &ignore_addresses)) { 172 krb5_free_address(context, &res->val[idx]); 173 flags &= ~LOOP_IF_NONE; /* we actually found an address, 174 so don't add any loop-back 175 addresses */ 176 continue; 177 } 178 179 idx++; 180 } 181 182 /* 183 * If no addresses were found, and LOOP_IF_NONE is set, then find 184 * the loopback addresses and add them to our list. 185 */ 186 if ((flags & LOOP_IF_NONE) != 0 && idx == 0) { 187 for (ifa = ifa0; ifa != NULL; ifa = ifa->ifa_next) { 188 if ((ifa->ifa_flags & IFF_UP) == 0) 189 continue; 190 if (ifa->ifa_addr == NULL) 191 continue; 192 if (memcmp(ifa->ifa_addr, &sa_zero, sizeof(sa_zero)) == 0) 193 continue; 194 if (krb5_sockaddr_uninteresting(ifa->ifa_addr)) 195 continue; 196 197 if ((ifa->ifa_flags & IFF_LOOPBACK) != 0) { 198 ret = krb5_sockaddr2address(context, 199 ifa->ifa_addr, &res->val[idx]); 200 if (ret) { 201 /* 202 * See comment above. 203 */ 204 continue; 205 } 206 if((flags & EXTRA_ADDRESSES) && 207 krb5_address_search(context, &res->val[idx], 208 &ignore_addresses)) { 209 krb5_free_address(context, &res->val[idx]); 210 continue; 211 } 212 idx++; 213 } 214 } 215 } 216 217 if (flags & EXTRA_ADDRESSES) 218 krb5_free_addresses(context, &ignore_addresses); 219 freeifaddrs(ifa0); 220 if (ret) 221 free(res->val); 222 else 223 res->len = idx; /* Now a count. */ 224 return (ret); 225 } 226 227 static krb5_error_code 228 get_addrs_int (krb5_context context, krb5_addresses *res, int flags) 229 { 230 krb5_error_code ret = -1; 231 232 if (flags & SCAN_INTERFACES) { 233 ret = find_all_addresses (context, res, flags); 234 if(ret || res->len == 0) 235 ret = gethostname_fallback (context, res); 236 } else { 237 res->len = 0; 238 res->val = NULL; 239 ret = 0; 240 } 241 242 if(ret == 0 && (flags & EXTRA_ADDRESSES)) { 243 krb5_addresses a; 244 /* append user specified addresses */ 245 ret = krb5_get_extra_addresses(context, &a); 246 if(ret) { 247 krb5_free_addresses(context, res); 248 return ret; 249 } 250 ret = krb5_append_addresses(context, res, &a); 251 if(ret) { 252 krb5_free_addresses(context, res); 253 return ret; 254 } 255 krb5_free_addresses(context, &a); 256 } 257 if(res->len == 0) { 258 free(res->val); 259 res->val = NULL; 260 } 261 return ret; 262 } 263 264 /* 265 * Try to get all addresses, but return the one corresponding to 266 * `hostname' if we fail. 267 * 268 * Only include loopback address if there are no other. 269 */ 270 271 krb5_error_code 272 krb5_get_all_client_addrs (krb5_context context, krb5_addresses *res) 273 { 274 int flags = LOOP_IF_NONE | EXTRA_ADDRESSES; 275 276 if (context->scan_interfaces) 277 flags |= SCAN_INTERFACES; 278 279 return get_addrs_int (context, res, flags); 280 } 281 282 /* 283 * Try to get all local addresses that a server should listen to. 284 * If that fails, we return the address corresponding to `hostname'. 285 */ 286 287 krb5_error_code 288 krb5_get_all_server_addrs (krb5_context context, krb5_addresses *res) 289 { 290 return get_addrs_int (context, res, LOOP | SCAN_INTERFACES); 291 } 292