| /* dnsmasq is Copyright (c) 2000-2015 Simon Kelley |
| |
| This program is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; version 2 dated June, 1991, or |
| (at your option) version 3 dated 29 June, 2007. |
| |
| This program is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| GNU General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with this program. If not, see <http://www.gnu.org/licenses/>. |
| */ |
| |
| #include "dnsmasq.h" |
| |
| #if defined(HAVE_BSD_NETWORK) || defined(HAVE_SOLARIS_NETWORK) |
| #include <ifaddrs.h> |
| |
| #include <sys/param.h> |
| #include <sys/sysctl.h> |
| #include <net/if.h> |
| #include <net/route.h> |
| #include <net/if_dl.h> |
| #include <netinet/if_ether.h> |
| #if defined(__FreeBSD__) |
| # include <net/if_var.h> |
| #endif |
| #include <netinet/in_var.h> |
| #ifdef HAVE_IPV6 |
| # include <netinet6/in6_var.h> |
| #endif |
| |
| #ifndef SA_SIZE |
| #define SA_SIZE(sa) \ |
| ( (!(sa) || ((struct sockaddr *)(sa))->sa_len == 0) ? \ |
| sizeof(long) : \ |
| 1 + ( (((struct sockaddr *)(sa))->sa_len - 1) | (sizeof(long) - 1) ) ) |
| #endif |
| |
| #ifdef HAVE_BSD_NETWORK |
| static int del_family = 0; |
| static struct all_addr del_addr; |
| #endif |
| |
| #if defined(HAVE_BSD_NETWORK) && !defined(__APPLE__) |
| |
| int arp_enumerate(void *parm, int (*callback)()) |
| { |
| int mib[6]; |
| size_t needed; |
| char *next; |
| struct rt_msghdr *rtm; |
| struct sockaddr_inarp *sin2; |
| struct sockaddr_dl *sdl; |
| struct iovec buff; |
| int rc; |
| |
| buff.iov_base = NULL; |
| buff.iov_len = 0; |
| |
| mib[0] = CTL_NET; |
| mib[1] = PF_ROUTE; |
| mib[2] = 0; |
| mib[3] = AF_INET; |
| mib[4] = NET_RT_FLAGS; |
| #ifdef RTF_LLINFO |
| mib[5] = RTF_LLINFO; |
| #else |
| mib[5] = 0; |
| #endif |
| if (sysctl(mib, 6, NULL, &needed, NULL, 0) == -1 || needed == 0) |
| return 0; |
| |
| while (1) |
| { |
| if (!expand_buf(&buff, needed)) |
| return 0; |
| if ((rc = sysctl(mib, 6, buff.iov_base, &needed, NULL, 0)) == 0 || |
| errno != ENOMEM) |
| break; |
| needed += needed / 8; |
| } |
| if (rc == -1) |
| return 0; |
| |
| for (next = buff.iov_base ; next < (char *)buff.iov_base + needed; next += rtm->rtm_msglen) |
| { |
| rtm = (struct rt_msghdr *)next; |
| sin2 = (struct sockaddr_inarp *)(rtm + 1); |
| sdl = (struct sockaddr_dl *)((char *)sin2 + SA_SIZE(sin2)); |
| if (!(*callback)(AF_INET, &sin2->sin_addr, LLADDR(sdl), sdl->sdl_alen, parm)) |
| return 0; |
| } |
| |
| return 1; |
| } |
| #endif /* defined(HAVE_BSD_NETWORK) && !defined(__APPLE__) */ |
| |
| |
| int iface_enumerate(int family, void *parm, int (*callback)()) |
| { |
| struct ifaddrs *head, *addrs; |
| int errsav, fd = -1, ret = 0; |
| |
| if (family == AF_UNSPEC) |
| #if defined(HAVE_BSD_NETWORK) && !defined(__APPLE__) |
| return arp_enumerate(parm, callback); |
| #else |
| return 0; /* need code for Solaris and MacOS*/ |
| #endif |
| |
| /* AF_LINK doesn't exist in Linux, so we can't use it in our API */ |
| if (family == AF_LOCAL) |
| family = AF_LINK; |
| |
| if (getifaddrs(&head) == -1) |
| return 0; |
| |
| #if defined(HAVE_BSD_NETWORK) && defined(HAVE_IPV6) |
| if (family == AF_INET6) |
| fd = socket(PF_INET6, SOCK_DGRAM, 0); |
| #endif |
| |
| for (addrs = head; addrs; addrs = addrs->ifa_next) |
| { |
| if (addrs->ifa_addr->sa_family == family) |
| { |
| int iface_index = if_nametoindex(addrs->ifa_name); |
| |
| if (iface_index == 0 || !addrs->ifa_addr || |
| (!addrs->ifa_netmask && family != AF_LINK)) |
| continue; |
| |
| if (family == AF_INET) |
| { |
| struct in_addr addr, netmask, broadcast; |
| addr = ((struct sockaddr_in *) addrs->ifa_addr)->sin_addr; |
| #ifdef HAVE_BSD_NETWORK |
| if (del_family == AF_INET && del_addr.addr.addr4.s_addr == addr.s_addr) |
| continue; |
| #endif |
| netmask = ((struct sockaddr_in *) addrs->ifa_netmask)->sin_addr; |
| if (addrs->ifa_broadaddr) |
| broadcast = ((struct sockaddr_in *) addrs->ifa_broadaddr)->sin_addr; |
| else |
| broadcast.s_addr = 0; |
| if (!((*callback)(addr, iface_index, NULL, netmask, broadcast, parm))) |
| goto err; |
| } |
| #ifdef HAVE_IPV6 |
| else if (family == AF_INET6) |
| { |
| struct in6_addr *addr = &((struct sockaddr_in6 *) addrs->ifa_addr)->sin6_addr; |
| unsigned char *netmask = (unsigned char *) &((struct sockaddr_in6 *) addrs->ifa_netmask)->sin6_addr; |
| int scope_id = ((struct sockaddr_in6 *) addrs->ifa_addr)->sin6_scope_id; |
| int i, j, prefix = 0; |
| u32 valid = 0xffffffff, preferred = 0xffffffff; |
| int flags = 0; |
| #ifdef HAVE_BSD_NETWORK |
| if (del_family == AF_INET6 && IN6_ARE_ADDR_EQUAL(&del_addr.addr.addr6, addr)) |
| continue; |
| #endif |
| #if defined(HAVE_BSD_NETWORK) && !defined(__APPLE__) |
| struct in6_ifreq ifr6; |
| |
| memset(&ifr6, 0, sizeof(ifr6)); |
| strncpy(ifr6.ifr_name, addrs->ifa_name, sizeof(ifr6.ifr_name)); |
| |
| ifr6.ifr_addr = *((struct sockaddr_in6 *) addrs->ifa_addr); |
| if (fd != -1 && ioctl(fd, SIOCGIFAFLAG_IN6, &ifr6) != -1) |
| { |
| if (ifr6.ifr_ifru.ifru_flags6 & IN6_IFF_TENTATIVE) |
| flags |= IFACE_TENTATIVE; |
| |
| if (ifr6.ifr_ifru.ifru_flags6 & IN6_IFF_DEPRECATED) |
| flags |= IFACE_DEPRECATED; |
| |
| #ifdef IN6_IFF_TEMPORARY |
| if (!(ifr6.ifr_ifru.ifru_flags6 & (IN6_IFF_AUTOCONF | IN6_IFF_TEMPORARY))) |
| flags |= IFACE_PERMANENT; |
| #endif |
| |
| #ifdef IN6_IFF_PRIVACY |
| if (!(ifr6.ifr_ifru.ifru_flags6 & (IN6_IFF_AUTOCONF | IN6_IFF_PRIVACY))) |
| flags |= IFACE_PERMANENT; |
| #endif |
| } |
| |
| ifr6.ifr_addr = *((struct sockaddr_in6 *) addrs->ifa_addr); |
| if (fd != -1 && ioctl(fd, SIOCGIFALIFETIME_IN6, &ifr6) != -1) |
| { |
| valid = ifr6.ifr_ifru.ifru_lifetime.ia6t_vltime; |
| preferred = ifr6.ifr_ifru.ifru_lifetime.ia6t_pltime; |
| } |
| #endif |
| |
| for (i = 0; i < IN6ADDRSZ; i++, prefix += 8) |
| if (netmask[i] != 0xff) |
| break; |
| |
| if (i != IN6ADDRSZ && netmask[i]) |
| for (j = 7; j > 0; j--, prefix++) |
| if ((netmask[i] & (1 << j)) == 0) |
| break; |
| |
| /* voodoo to clear interface field in address */ |
| if (!option_bool(OPT_NOWILD) && IN6_IS_ADDR_LINKLOCAL(addr)) |
| { |
| addr->s6_addr[2] = 0; |
| addr->s6_addr[3] = 0; |
| } |
| |
| if (!((*callback)(addr, prefix, scope_id, iface_index, flags, |
| (int) preferred, (int)valid, parm))) |
| goto err; |
| } |
| #endif /* HAVE_IPV6 */ |
| |
| #ifdef HAVE_DHCP6 |
| else if (family == AF_LINK) |
| { |
| /* Assume ethernet again here */ |
| struct sockaddr_dl *sdl = (struct sockaddr_dl *) addrs->ifa_addr; |
| if (sdl->sdl_alen != 0 && |
| !((*callback)(iface_index, ARPHRD_ETHER, LLADDR(sdl), sdl->sdl_alen, parm))) |
| goto err; |
| } |
| #endif |
| } |
| } |
| |
| ret = 1; |
| |
| err: |
| errsav = errno; |
| freeifaddrs(head); |
| if (fd != -1) |
| close(fd); |
| errno = errsav; |
| |
| return ret; |
| } |
| #endif /* defined(HAVE_BSD_NETWORK) || defined(HAVE_SOLARIS_NETWORK) */ |
| |
| |
| #if defined(HAVE_BSD_NETWORK) && defined(HAVE_DHCP) |
| #include <net/bpf.h> |
| |
| void init_bpf(void) |
| { |
| int i = 0; |
| |
| while (1) |
| { |
| sprintf(daemon->dhcp_buff, "/dev/bpf%d", i++); |
| if ((daemon->dhcp_raw_fd = open(daemon->dhcp_buff, O_RDWR, 0)) != -1) |
| return; |
| |
| if (errno != EBUSY) |
| die(_("cannot create DHCP BPF socket: %s"), NULL, EC_BADNET); |
| } |
| } |
| |
| void send_via_bpf(struct dhcp_packet *mess, size_t len, |
| struct in_addr iface_addr, struct ifreq *ifr) |
| { |
| /* Hairy stuff, packet either has to go to the |
| net broadcast or the destination can't reply to ARP yet, |
| but we do know the physical address. |
| Build the packet by steam, and send directly, bypassing |
| the kernel IP stack */ |
| |
| struct ether_header ether; |
| struct ip ip; |
| struct udphdr { |
| u16 uh_sport; /* source port */ |
| u16 uh_dport; /* destination port */ |
| u16 uh_ulen; /* udp length */ |
| u16 uh_sum; /* udp checksum */ |
| } udp; |
| |
| u32 i, sum; |
| struct iovec iov[4]; |
| |
| /* Only know how to do ethernet on *BSD */ |
| if (mess->htype != ARPHRD_ETHER || mess->hlen != ETHER_ADDR_LEN) |
| { |
| my_syslog(MS_DHCP | LOG_WARNING, _("DHCP request for unsupported hardware type (%d) received on %s"), |
| mess->htype, ifr->ifr_name); |
| return; |
| } |
| |
| ifr->ifr_addr.sa_family = AF_LINK; |
| if (ioctl(daemon->dhcpfd, SIOCGIFADDR, ifr) < 0) |
| return; |
| |
| memcpy(ether.ether_shost, LLADDR((struct sockaddr_dl *)&ifr->ifr_addr), ETHER_ADDR_LEN); |
| ether.ether_type = htons(ETHERTYPE_IP); |
| |
| if (ntohs(mess->flags) & 0x8000) |
| { |
| memset(ether.ether_dhost, 255, ETHER_ADDR_LEN); |
| ip.ip_dst.s_addr = INADDR_BROADCAST; |
| } |
| else |
| { |
| memcpy(ether.ether_dhost, mess->chaddr, ETHER_ADDR_LEN); |
| ip.ip_dst.s_addr = mess->yiaddr.s_addr; |
| } |
| |
| ip.ip_p = IPPROTO_UDP; |
| ip.ip_src.s_addr = iface_addr.s_addr; |
| ip.ip_len = htons(sizeof(struct ip) + |
| sizeof(struct udphdr) + |
| len) ; |
| ip.ip_hl = sizeof(struct ip) / 4; |
| ip.ip_v = IPVERSION; |
| ip.ip_tos = 0; |
| ip.ip_id = htons(0); |
| ip.ip_off = htons(0x4000); /* don't fragment */ |
| ip.ip_ttl = IPDEFTTL; |
| ip.ip_sum = 0; |
| for (sum = 0, i = 0; i < sizeof(struct ip) / 2; i++) |
| sum += ((u16 *)&ip)[i]; |
| while (sum>>16) |
| sum = (sum & 0xffff) + (sum >> 16); |
| ip.ip_sum = (sum == 0xffff) ? sum : ~sum; |
| |
| udp.uh_sport = htons(daemon->dhcp_server_port); |
| udp.uh_dport = htons(daemon->dhcp_client_port); |
| if (len & 1) |
| ((char *)mess)[len] = 0; /* for checksum, in case length is odd. */ |
| udp.uh_sum = 0; |
| udp.uh_ulen = sum = htons(sizeof(struct udphdr) + len); |
| sum += htons(IPPROTO_UDP); |
| sum += ip.ip_src.s_addr & 0xffff; |
| sum += (ip.ip_src.s_addr >> 16) & 0xffff; |
| sum += ip.ip_dst.s_addr & 0xffff; |
| sum += (ip.ip_dst.s_addr >> 16) & 0xffff; |
| for (i = 0; i < sizeof(struct udphdr)/2; i++) |
| sum += ((u16 *)&udp)[i]; |
| for (i = 0; i < (len + 1) / 2; i++) |
| sum += ((u16 *)mess)[i]; |
| while (sum>>16) |
| sum = (sum & 0xffff) + (sum >> 16); |
| udp.uh_sum = (sum == 0xffff) ? sum : ~sum; |
| |
| ioctl(daemon->dhcp_raw_fd, BIOCSETIF, ifr); |
| |
| iov[0].iov_base = ðer; |
| iov[0].iov_len = sizeof(ether); |
| iov[1].iov_base = &ip; |
| iov[1].iov_len = sizeof(ip); |
| iov[2].iov_base = &udp; |
| iov[2].iov_len = sizeof(udp); |
| iov[3].iov_base = mess; |
| iov[3].iov_len = len; |
| |
| while (retry_send(writev(daemon->dhcp_raw_fd, iov, 4))); |
| } |
| |
| #endif /* defined(HAVE_BSD_NETWORK) && defined(HAVE_DHCP) */ |
| |
| |
| #ifdef HAVE_BSD_NETWORK |
| |
| void route_init(void) |
| { |
| /* AF_UNSPEC: all addr families */ |
| daemon->routefd = socket(PF_ROUTE, SOCK_RAW, AF_UNSPEC); |
| |
| if (daemon->routefd == -1 || !fix_fd(daemon->routefd)) |
| die(_("cannot create PF_ROUTE socket: %s"), NULL, EC_BADNET); |
| } |
| |
| void route_sock(void) |
| { |
| struct if_msghdr *msg; |
| int rc = recv(daemon->routefd, daemon->packet, daemon->packet_buff_sz, 0); |
| |
| if (rc < 4) |
| return; |
| |
| msg = (struct if_msghdr *)daemon->packet; |
| |
| if (rc < msg->ifm_msglen) |
| return; |
| |
| if (msg->ifm_version != RTM_VERSION) |
| { |
| static int warned = 0; |
| if (!warned) |
| { |
| my_syslog(LOG_WARNING, _("Unknown protocol version from route socket")); |
| warned = 1; |
| } |
| } |
| else if (msg->ifm_type == RTM_NEWADDR) |
| { |
| del_family = 0; |
| queue_event(EVENT_NEWADDR); |
| } |
| else if (msg->ifm_type == RTM_DELADDR) |
| { |
| /* There's a race in the kernel, such that if we run iface_enumerate() immediately |
| we get a DELADDR event, the deleted address still appears. Here we store the deleted address |
| in a static variable, and omit it from the set returned by iface_enumerate() */ |
| int mask = ((struct ifa_msghdr *)msg)->ifam_addrs; |
| int maskvec[] = { RTA_DST, RTA_GATEWAY, RTA_NETMASK, RTA_GENMASK, |
| RTA_IFP, RTA_IFA, RTA_AUTHOR, RTA_BRD }; |
| int of; |
| unsigned int i; |
| |
| for (i = 0, of = sizeof(struct ifa_msghdr); of < rc && i < sizeof(maskvec)/sizeof(maskvec[0]); i++) |
| if (mask & maskvec[i]) |
| { |
| struct sockaddr *sa = (struct sockaddr *)((char *)msg + of); |
| size_t diff = (sa->sa_len != 0) ? sa->sa_len : sizeof(long); |
| |
| if (maskvec[i] == RTA_IFA) |
| { |
| del_family = sa->sa_family; |
| if (del_family == AF_INET) |
| del_addr.addr.addr4 = ((struct sockaddr_in *)sa)->sin_addr; |
| #ifdef HAVE_IPV6 |
| else if (del_family == AF_INET6) |
| del_addr.addr.addr6 = ((struct sockaddr_in6 *)sa)->sin6_addr; |
| #endif |
| else |
| del_family = 0; |
| } |
| |
| of += diff; |
| /* round up as needed */ |
| if (diff & (sizeof(long) - 1)) |
| of += sizeof(long) - (diff & (sizeof(long) - 1)); |
| } |
| |
| queue_event(EVENT_NEWADDR); |
| } |
| } |
| |
| #endif /* HAVE_BSD_NETWORK */ |
| |
| |