/* * BIRD -- Unix Interface Scanning and Syncing * * (c) 1998--1999 Martin Mares <mj@ucw.cz> * * Can be freely distributed and used under the terms of the GNU GPL. */ #include <string.h> #include <sys/types.h> #include <sys/socket.h> #include <netinet/in.h> #include <net/if.h> #include <sys/ioctl.h> #include <errno.h> #define LOCAL_DEBUG #include "nest/bird.h" #include "nest/iface.h" #include "nest/route.h" #include "nest/protocol.h" #include "lib/timer.h" #include "lib/krt.h" #include "unix.h" int if_scan_sock = -1; static void scan_ifs(struct ifreq *r, int cnt) { struct iface i, *pi; struct ifa a; char *err, *colon; unsigned fl; ip_addr netmask; int l; if_start_update(); for (cnt /= sizeof(struct ifreq); cnt; cnt--, r++) { int sec = 0; bzero(&i, sizeof(i)); bzero(&a, sizeof(a)); DBG("%s\n", r->ifr_name); if (colon = strchr(r->ifr_name, ':')) { /* It's an alias -- let's interpret it as a secondary interface address */ sec = 1; *colon = 0; } strncpy(i.name, r->ifr_name, sizeof(i.name) - 1); get_sockaddr((struct sockaddr_in *) &r->ifr_addr, &a.ip, NULL); if (ipa_nonzero(a.ip)) { l = ipa_classify(a.ip); if (l < 0 || !(l & IADDR_HOST)) { log(L_ERR "%s: Invalid interface address", i.name); a.ip = IPA_NONE; } else { a.scope = l & IADDR_SCOPE_MASK; if (a.scope == SCOPE_HOST) i.flags |= IF_LOOPBACK | IF_IGNORE; } } if (ioctl(if_scan_sock, SIOCGIFFLAGS, r) < 0) { err = "SIOCGIFFLAGS"; faulty: log(L_ERR "%s(%s): %m", err, i.name); bad: i.flags = (i.flags & ~IF_LINK_UP) | IF_ADMIN_DOWN; continue; } fl = r->ifr_flags; if (fl & IFF_UP) i.flags |= IF_LINK_UP; if (ioctl(if_scan_sock, SIOCGIFNETMASK, r) < 0) { err = "SIOCGIFNETMASK"; goto faulty; } get_sockaddr((struct sockaddr_in *) &r->ifr_addr, &netmask, NULL); l = ipa_mklen(netmask); if (l < 0 || l == 31) { log(L_ERR "%s: Invalid netmask", i.name); goto bad; } a.pxlen = l; if (fl & IFF_POINTOPOINT) { a.flags |= IA_UNNUMBERED; if (ioctl(if_scan_sock, SIOCGIFDSTADDR, r) < 0) { err = "SIOCGIFDSTADDR"; goto faulty; } get_sockaddr((struct sockaddr_in *) &r->ifr_addr, &a.opposite, NULL); a.prefix = a.opposite; a.pxlen = BITS_PER_IP_ADDRESS; } else a.prefix = ipa_and(a.ip, ipa_mkmask(a.pxlen)); if (fl & IFF_LOOPBACK) i.flags |= IF_LOOPBACK | IF_IGNORE; if (1 #ifndef CONFIG_ALL_MULTICAST && (fl & IFF_MULTICAST) #endif #ifndef CONFIG_UNNUM_MULTICAST && !(a.flags & IA_UNNUMBERED) #endif ) i.flags |= IF_MULTICAST; if (a.pxlen < 32) { a.brd = ipa_or(a.prefix, ipa_not(ipa_mkmask(a.pxlen))); if (ipa_equal(a.ip, a.prefix) || ipa_equal(a.ip, a.brd)) { log(L_ERR "%s: Using network or broadcast address for interface", i.name); goto bad; } if (fl & IFF_BROADCAST) i.flags |= IF_BROADCAST; if (a.pxlen < 30) i.flags |= IF_MULTIACCESS; else a.opposite = ipa_opposite(a.ip); } else a.brd = a.opposite; if (ioctl(if_scan_sock, SIOCGIFMTU, r) < 0) { err = "SIOCGIFMTU"; goto faulty; } i.mtu = r->ifr_mtu; #ifdef SIOCGIFINDEX if (ioctl(if_scan_sock, SIOCGIFINDEX, r) >= 0) i.index = r->ifr_ifindex; else if (errno != -EINVAL) DBG("SIOCGIFINDEX failed: %m\n"); else /* defined, but not supported by the kernel */ #endif /* * The kernel doesn't give us real ifindices, but we still need them * at least for OSPF unnumbered links. So let's make them up ourselves. */ if (pi = if_find_by_name(i.name)) i.index = pi->index; else { static int if_index_counter = 1; i.index = if_index_counter++; } pi = NULL; if (sec) { a.flags |= IA_SECONDARY; pi = if_find_by_index(i.index); } if (!pi) pi = if_update(&i); a.iface = pi; ifa_update(&a); } if_end_update(); } void krt_if_scan(struct kif_proto *p) { struct ifconf ic; static int last_ifbuf_size = 4*sizeof(struct ifreq); int res; for(;;) { if (last_ifbuf_size) { struct ifreq *r = alloca(last_ifbuf_size); ic.ifc_ifcu.ifcu_req = r; ic.ifc_len = last_ifbuf_size; res = ioctl(if_scan_sock, SIOCGIFCONF, &ic); if (res < 0 && errno != EFAULT) die("SIOCCGIFCONF: %m"); if (res >= 0 && ic.ifc_len < last_ifbuf_size) { scan_ifs(r, ic.ifc_len); break; } } #if 0 /* * Linux 2.1 and higher supports this, but it's not needed since * we prefer to use Netlink there anyway. */ ic.ifc_req = NULL; ic.ifc_len = 999999999; if (ioctl(if_scan_sock, SIOCGIFCONF, &ic) < 0) die("SIOCIFCONF: %m"); ic.ifc_len += sizeof(struct ifreq); if (last_ifbuf_size < ic.ifc_len) { last_ifbuf_size = ic.ifc_len; DBG("Increased ifconf buffer size to %d\n", last_ifbuf_size); } #else last_ifbuf_size *= 2; DBG("Increased ifconf buffer size to %d\n", last_ifbuf_size); #endif } } void krt_if_construct(struct kif_config *c) { } void krt_if_start(struct kif_proto *p) { } void krt_if_shutdown(struct kif_proto *p) { } void krt_if_io_init(void) { if_scan_sock = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP); DBG("Using socket %d for interface and route scanning\n", if_scan_sock); if (if_scan_sock < 0) die("Cannot create scanning socket: %m"); }