/* * $Id: if_addr.c,v 1.2 1999/05/27 02:32:19 dugsong Exp $ * * libnet * if_addr.c - interface selection code * * Copyright (c) 1998, 1999 Mike D. Schiffman * route|daemon9 * Originally pulled from traceroute sources. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * */ #if (HAVE_CONFIG_H) #include "../include/config.h" #endif #include "../include/libnet.h" #ifdef HAVE_SYS_SOCKIO_H #include #endif #define MAX_IPADDR 32 /* * Return the interface list */ int ifaddrlist(register struct libnet_ifaddr_list **ipaddrp, register char *errbuf) { register int fd, nipaddr; #ifdef HAVE_SOCKADDR_SA_LEN register int n; #endif register struct ifreq *ifrp, *ifend, *ifnext, *mp; register struct sockaddr_in *sin; register struct libnet_ifaddr_list *al; struct ifconf ifc; struct ifreq ibuf[MAX_IPADDR], ifr; char device[sizeof(ifr.ifr_name) + 1]; static struct libnet_ifaddr_list ifaddrlist[MAX_IPADDR]; fd = socket(AF_INET, SOCK_DGRAM, 0); if (fd < 0) { sprintf(errbuf, "socket: %s", strerror(errno)); return (-1); } ifc.ifc_len = sizeof(ibuf); ifc.ifc_buf = (caddr_t)ibuf; if (ioctl(fd, SIOCGIFCONF, (char *)&ifc) < 0 || ifc.ifc_len < sizeof(struct ifreq)) { sprintf(errbuf, "SIOCGIFCONF: %s", strerror(errno)); close(fd); return (-1); } ifrp = ibuf; ifend = (struct ifreq *)((char *)ibuf + ifc.ifc_len); al = ifaddrlist; mp = NULL; nipaddr = 0; for (; ifrp < ifend; ifrp = ifnext) { #ifdef HAVE_SOCKADDR_SA_LEN n = ifrp->ifr_addr.sa_len + sizeof(ifrp->ifr_name); if (n < sizeof(*ifrp)) { ifnext = ifrp + 1; } else { ifnext = (struct ifreq *)((char *)ifrp + n); } if (ifrp->ifr_addr.sa_family != AF_INET) continue; #else ifnext = ifrp + 1; #endif /* * Need a template to preserve address info that is * used below to locate the next entry. (Otherwise, * SIOCGIFFLAGS stomps over it because the requests * are returned in a union.) */ strncpy(ifr.ifr_name, ifrp->ifr_name, sizeof(ifr.ifr_name)); if (ioctl(fd, SIOCGIFFLAGS, (char *)&ifr) < 0) { if (errno == ENXIO) continue; sprintf(errbuf, "SIOCGIFFLAGS: %.*s: %s", (int)sizeof(ifr.ifr_name), ifr.ifr_name, strerror(errno)); close(fd); return (-1); } /* Must be up and not the loopback */ if ((ifr.ifr_flags & IFF_UP) == 0 || ISLOOPBACK(&ifr)) continue; strncpy(device, ifr.ifr_name, sizeof(ifr.ifr_name)); device[sizeof(device) - 1] = '\0'; if (ioctl(fd, SIOCGIFADDR, (char *)&ifr) < 0) { sprintf(errbuf, "SIOCGIFADDR: %s: %s", device, strerror(errno)); close(fd); return (-1); } sin = (struct sockaddr_in *)&ifr.ifr_addr; al->addr = sin->sin_addr.s_addr; /* * Replaced savestr() with strdup(). -- MDS */ al->device = strdup(device); ++al; ++nipaddr; } close(fd); *ipaddrp = ifaddrlist; return (nipaddr); } int libnet_select_device(struct sockaddr_in *sin, u_char **device, u_char *errbuf) { int c, i; char err_buf[132]; struct libnet_ifaddr_list *address_list; #if (__solaris__) /* * XXX - this is temporary and needs to be better documented. */ *device = "le0"; return (1); #else /* * Number of interfaces. */ c = ifaddrlist(&address_list, err_buf); if (c < 0) { sprintf(errbuf, "ifaddrlist : %s\n", err_buf); return (-1); } else if (c == 0) { sprintf(errbuf, "No network interfaces found.\n"); return (-1); } if (*device) { for (i = c; i; --i, ++address_list) { if (!(strcmp(*device, address_list->device))) { break; } } if (i <= 0) { sprintf(errbuf, "Can't find interface %s\n", *device); return (-1); } } sin->sin_family = AF_INET; sin->sin_addr.s_addr = address_list->addr; /* * Do we need to assign a name to device? */ if (!*device) { if (c > 1) { #if (__DEBUG) fprintf(stdout, "Multiple interfaces found, using %s @ %s.\n", host_lookup(sin->sin_addr.s_addr, 0), address_list->device); #endif } *device = address_list->device; return (1); } return (-1); } #endif /* __solaris__ */ #if RAW_IS_COOKED int libnet_select_device_by_ip(u_char **device, u_long ip, u_char *errbuf) { int c, i; char err_buf[132]; struct libnet_ifaddr_list *address_list; /* * Number of interfaces. */ c = ifaddrlist(&address_list, err_buf); if (c < 0) { sprintf(errbuf, "ifaddrlist : %s\n", err_buf); return (-1); } else if (c == 0) { sprintf(errbuf, "No network interfaces found.\n"); return (-1); } for (i = c; i; --i, ++address_list) { if (ip==address_list->addr) { break; } } if (i <= 0) { sprintf(errbuf, "Can't find interface that matches %s.\n", host_lookup(ip,0)); return (-1); } *device = address_list->device; return (1); } #endif /* RAW_IS_COOKED */ /* EOF */