1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright 2004 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 28 29 #include <stdio.h> 30 #include <sys/types.h> 31 #include <sys/socket.h> 32 #include <netdb.h> 33 #include <unistd.h> 34 #include <sys/types.h> 35 #include <sys/socket.h> 36 #include <sys/sockio.h> 37 #include <net/if.h> 38 #include <netinet/in.h> 39 #include <arpa/inet.h> 40 #include <errno.h> 41 #include <stdlib.h> 42 #include <string.h> 43 #include <libintl.h> 44 45 static int is_local_if(struct hostent *hp); 46 47 /* 48 * Given a host name, check to see if it points to the local host. 49 * If it does, return 1, else return 0. 50 * 51 * The strategy is this: translate the host name argument to a list of 52 * addresses. Then compare each of those addresses to the addresses of 53 * network interfaces on this host. 54 */ 55 int 56 is_local_host(char *host) 57 { 58 struct hostent *hp; 59 int err; 60 int flags = AI_DEFAULT; 61 62 if (hp = getipnodebyname((const char *) host, AF_INET, flags, &err)) 63 if (is_local_if(hp)) 64 return (1); 65 if (hp = getipnodebyname((const char *) host, AF_INET6, flags, &err)) 66 if (is_local_if(hp)) 67 return (1); 68 69 return (0); 70 } 71 72 static int 73 is_local_if(struct hostent *hp) 74 { 75 char *buf; 76 struct lifconf lifc; 77 struct lifnum lifn; 78 struct lifreq lifr; 79 struct lifreq *lifrp; 80 int bufsiz; 81 int nha; 82 int nif; 83 int s; 84 85 if ((s = socket(hp->h_addrtype, SOCK_DGRAM, 0)) == -1) { 86 perror("socket"); 87 return (0); 88 } 89 90 lifn.lifn_family = hp->h_addrtype; 91 lifn.lifn_flags = LIFC_EXTERNAL_SOURCE; 92 if (ioctl(s, SIOCGLIFNUM, (char *)&lifn) == -1) { 93 perror("SIOCGLIFNUM"); 94 (void) close(s); 95 return (0); 96 } 97 bufsiz = lifn.lifn_count * sizeof (struct lifreq); 98 99 if ((buf = malloc(bufsiz)) == NULL) { 100 perror("malloc"); 101 (void) close(s); 102 return (0); 103 } 104 105 lifc.lifc_family = hp->h_addrtype; 106 lifc.lifc_flags = LIFC_EXTERNAL_SOURCE; 107 lifc.lifc_len = bufsiz; 108 lifc.lifc_buf = buf; 109 if (ioctl(s, SIOCGLIFCONF, (char *)&lifc) == -1) { 110 perror("SIOCGLIFCONF"); 111 (void) close(s); 112 free(buf); 113 return (0); 114 } 115 116 #define lifraddrp(lifrp) ((lifrp->lifr_addr.ss_family == AF_INET6) ? \ 117 (void *) &((struct sockaddr_in6 *)&lifrp->lifr_addr)->sin6_addr : \ 118 (void *) &((struct sockaddr_in *)&lifrp->lifr_addr)->sin_addr) 119 120 for (lifrp = lifc.lifc_req, 121 nif = lifc.lifc_len / sizeof (struct lifreq); 122 nif > 0; nif--, lifrp++) { 123 if (lifrp->lifr_addr.ss_family != hp->h_addrtype) { 124 continue; 125 } 126 (void) memset(&lifr, 0, sizeof (lifr)); 127 (void) strncpy(lifr.lifr_name, lifrp->lifr_name, 128 sizeof (lifr.lifr_name)); 129 if (ioctl(s, SIOCGLIFFLAGS, (caddr_t)&lifr) == -1) { 130 perror("SIOCGLIFFLAGS"); 131 (void) close(s); 132 free(buf); 133 return (0); 134 } 135 136 for (nha = 0; hp->h_addr_list[nha]; nha++) { 137 if (memcmp(hp->h_addr_list[nha], lifraddrp(lifrp), 138 hp->h_length) == 0) { 139 (void) close(s); 140 free(buf); 141 return (1); 142 } 143 } 144 } 145 146 #undef lifraddrp 147 148 (void) close(s); 149 free(buf); 150 return (0); 151 } 152