X-Git-Url: http://git.archive.openwrt.org/?p=project%2Fodhcpd.git;a=blobdiff_plain;f=src%2Fndp.c;h=72fd3bc37d87e360caf2d30c75dffd972cebb3ed;hp=027e9ab53e8d117bd766fda968843230c0e85734;hb=96033e937c56a407d8ca9302c5901cd77366da29;hpb=fb47b59a249adaff373aefe1bf09e635082ee0b3 diff --git a/src/ndp.c b/src/ndp.c index 027e9ab..72fd3bc 100644 --- a/src/ndp.c +++ b/src/ndp.c @@ -26,24 +26,20 @@ #include #include -#include #include -#include "router.h" -#include "ndp.h" +#include +#include "dhcpv6.h" +#include "odhcpd.h" +static void ndp_netevent_cb(unsigned long event, struct netevent_handler_info *info); +static void setup_route(struct in6_addr *addr, struct interface *iface, bool add); +static void setup_addr_for_relaying(struct in6_addr *addr, struct interface *iface, bool add); static void handle_solicit(void *addr, void *data, size_t len, struct interface *iface, void *dest); -static void handle_rtnetlink(void *addr, void *data, size_t len, - struct interface *iface, void *dest); -static ssize_t ping6(struct in6_addr *addr, - const struct interface *iface); -static uint32_t rtnl_seqid = 0; static int ping_socket = -1; -static struct odhcpd_event rtnl_event = {{.fd = -1}, handle_rtnetlink}; - // Filter ICMPv6 messages of type neighbor soliciation static struct sock_filter bpf[] = { @@ -56,33 +52,20 @@ static struct sock_filter bpf[] = { BPF_STMT(BPF_RET | BPF_K, 0), }; static const struct sock_fprog bpf_prog = {sizeof(bpf) / sizeof(*bpf), bpf}; - +static struct netevent_handler ndp_netevent_handler = { .cb = ndp_netevent_cb, }; // Initialize NDP-proxy -int init_ndp(void) +int ndp_init(void) { - // Setup netlink socket - if ((rtnl_event.uloop.fd = odhcpd_open_rtnl()) < 0) - return -1; - - // Receive netlink neighbor and ip-address events - uint32_t group = RTNLGRP_IPV6_IFADDR; - setsockopt(rtnl_event.uloop.fd, SOL_NETLINK, - NETLINK_ADD_MEMBERSHIP, &group, sizeof(group)); - group = RTNLGRP_IPV6_ROUTE; - setsockopt(rtnl_event.uloop.fd, SOL_NETLINK, - NETLINK_ADD_MEMBERSHIP, &group, sizeof(group)); - - odhcpd_register(&rtnl_event); + int val = 2; // Open ICMPv6 socket ping_socket = socket(AF_INET6, SOCK_RAW | SOCK_CLOEXEC, IPPROTO_ICMPV6); if (ping_socket < 0) { - syslog(LOG_ERR, "Unable to open raw socket: %s", strerror(errno)); + syslog(LOG_ERR, "Unable to open raw socket: %m"); return -1; } - int val = 2; setsockopt(ping_socket, IPPROTO_RAW, IPV6_CHECKSUM, &val, sizeof(val)); // This is required by RFC 4861 @@ -95,71 +78,44 @@ int init_ndp(void) ICMP6_FILTER_SETBLOCKALL(&filt); setsockopt(ping_socket, IPPROTO_ICMPV6, ICMP6_FILTER, &filt, sizeof(filt)); - - // Netlink socket, continued... - group = RTNLGRP_NEIGH; - setsockopt(rtnl_event.uloop.fd, SOL_NETLINK, NETLINK_ADD_MEMBERSHIP, &group, sizeof(group)); + netlink_add_netevent_handler(&ndp_netevent_handler); return 0; } - -static void dump_neigh_table(bool proxy) -{ - struct { - struct nlmsghdr nh; - struct ndmsg ndm; - } req = { - {sizeof(req), RTM_GETNEIGH, NLM_F_REQUEST | NLM_F_DUMP, - ++rtnl_seqid, 0}, - {.ndm_family = AF_INET6, .ndm_flags = (proxy) ? NTF_PROXY : 0} - }; - send(rtnl_event.uloop.fd, &req, sizeof(req), MSG_DONTWAIT); - odhcpd_process(&rtnl_event); -} - - -int setup_ndp_interface(struct interface *iface, bool enable) +int ndp_setup_interface(struct interface *iface, bool enable) { + int ret = 0, procfd; + bool dump_neigh = false; char procbuf[64]; + snprintf(procbuf, sizeof(procbuf), "/proc/sys/net/ipv6/conf/%s/proxy_ndp", iface->ifname); - int procfd = open(procbuf, O_WRONLY); - bool dump_neigh = false; + procfd = open(procbuf, O_WRONLY); + + if (procfd < 0) { + ret = -1; + goto out; + } if (iface->ndp_event.uloop.fd > 0) { uloop_fd_delete(&iface->ndp_event.uloop); close(iface->ndp_event.uloop.fd); iface->ndp_event.uloop.fd = -1; - if (!enable || iface->ndp != RELAYD_RELAY) + if (!enable || iface->ndp != MODE_RELAY) if (write(procfd, "0\n", 2) < 0) {} dump_neigh = true; } - if (enable && (iface->ra == RELAYD_SERVER || - iface->dhcpv6 == RELAYD_SERVER || iface->ndp == RELAYD_RELAY)) { - // Synthesize initial address events - struct { - struct nlmsghdr nh; - struct ifaddrmsg ifa; - } req2 = { - {sizeof(req2), RTM_GETADDR, NLM_F_REQUEST | NLM_F_DUMP, - ++rtnl_seqid, 0}, - {.ifa_family = AF_INET6, .ifa_index = iface->ifindex} - }; - send(rtnl_event.uloop.fd, &req2, sizeof(req2), MSG_DONTWAIT); - } - - if (enable && iface->ndp == RELAYD_RELAY) { + if (enable && iface->ndp == MODE_RELAY) { if (write(procfd, "1\n", 2) < 0) {} - close(procfd); int sock = socket(AF_PACKET, SOCK_DGRAM | SOCK_CLOEXEC, htons(ETH_P_IPV6)); if (sock < 0) { - syslog(LOG_ERR, "Unable to open packet socket: %s", - strerror(errno)); - return -1; + syslog(LOG_ERR, "Unable to open packet socket: %m"); + ret = -1; + goto out; } #ifdef PACKET_RECV_TYPE @@ -169,8 +125,9 @@ int setup_ndp_interface(struct interface *iface, bool enable) if (setsockopt(sock, SOL_SOCKET, SO_ATTACH_FILTER, &bpf_prog, sizeof(bpf_prog))) { - syslog(LOG_ERR, "Failed to set BPF: %s", strerror(errno)); - return -1; + syslog(LOG_ERR, "Failed to set BPF: %m"); + ret = -1; + goto out; } struct sockaddr_ll ll = { @@ -193,35 +150,83 @@ int setup_ndp_interface(struct interface *iface, bool enable) // If we already were enabled dump is unnecessary, if not do dump if (!dump_neigh) - dump_neigh_table(false); + netlink_dump_neigh_table(false); else dump_neigh = false; - } else { - close(procfd); } if (dump_neigh) - dump_neigh_table(true); + netlink_dump_neigh_table(true); - return 0; +out: + if (procfd >= 0) + close(procfd); + + return ret; } +static void ndp_netevent_cb(unsigned long event, struct netevent_handler_info *info) +{ + struct interface *iface = info->iface; + bool add = true; + + if (!iface || iface->ndp == MODE_DISABLED) + return; + + switch (event) { + case NETEV_ADDR6_DEL: + add = false; + netlink_dump_neigh_table(false); + /* fall through */ + case NETEV_ADDR6_ADD: + setup_addr_for_relaying(&info->addr.in6, iface, add); + break; + case NETEV_NEIGH6_DEL: + add = false; + /* fall through */ + case NETEV_NEIGH6_ADD: + if (info->neigh.flags & NTF_PROXY) { + if (add) { + netlink_setup_proxy_neigh(&info->neigh.dst.in6, iface->ifindex, false); + setup_route(&info->neigh.dst.in6, iface, false); + netlink_dump_neigh_table(false); + } + break; + } + + if (add && + !(info->neigh.state & + (NUD_REACHABLE|NUD_STALE|NUD_DELAY|NUD_PROBE|NUD_PERMANENT|NUD_NOARP))) + break; + + setup_addr_for_relaying(&info->neigh.dst.in6, iface, add); + setup_route(&info->neigh.dst.in6, iface, add); + + if (!add) + netlink_dump_neigh_table(false); + break; + default: + break; + } +} // Send an ICMP-ECHO. This is less for actually pinging but for the // neighbor cache to be kept up-to-date. -static ssize_t ping6(struct in6_addr *addr, +static void ping6(struct in6_addr *addr, const struct interface *iface) { - struct sockaddr_in6 dest = {AF_INET6, 0, 0, *addr, iface->ifindex}; - struct icmp6_hdr echo = {.icmp6_type = ICMP6_ECHO_REQUEST}; - struct iovec iov = {&echo, sizeof(echo)}; - - // Linux seems to not honor IPV6_PKTINFO on raw-sockets, so work around - setsockopt(ping_socket, SOL_SOCKET, SO_BINDTODEVICE, - iface->ifname, sizeof(iface->ifname)); - return odhcpd_send(ping_socket, &dest, &iov, 1, iface); -} + struct sockaddr_in6 dest = { .sin6_family = AF_INET6, .sin6_addr = *addr, .sin6_scope_id = iface->ifindex, }; + struct icmp6_hdr echo = { .icmp6_type = ICMP6_ECHO_REQUEST }; + struct iovec iov = { .iov_base = &echo, .iov_len = sizeof(echo) }; + char ipbuf[INET6_ADDRSTRLEN]; + inet_ntop(AF_INET6, addr, ipbuf, sizeof(ipbuf)); + syslog(LOG_NOTICE, "Pinging for %s%%%s", ipbuf, iface->ifname); + + netlink_setup_route(addr, 128, iface->ifindex, NULL, 128, true); + odhcpd_send(ping_socket, &dest, &iov, 1, iface); + netlink_setup_route(addr, 128, iface->ifindex, NULL, 128, false); +} // Handle solicitations static void handle_solicit(void *addr, void *data, size_t len, @@ -230,13 +235,16 @@ static void handle_solicit(void *addr, void *data, size_t len, struct ip6_hdr *ip6 = data; struct nd_neighbor_solicit *req = (struct nd_neighbor_solicit*)&ip6[1]; struct sockaddr_ll *ll = addr; + char ipbuf[INET6_ADDRSTRLEN]; + uint8_t mac[6]; // Solicitation is for duplicate address detection bool ns_is_dad = IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src); + // Don't process solicit messages on non relay interfaces // Don't forward any non-DAD solicitation for external ifaces // TODO: check if we should even forward DADs for them - if (iface->external && !ns_is_dad) + if (iface->ndp != MODE_RELAY || (iface->external && !ns_is_dad)) return; if (len < sizeof(*ip6) + sizeof(*req)) @@ -247,257 +255,53 @@ static void handle_solicit(void *addr, void *data, size_t len, IN6_IS_ADDR_MULTICAST(&req->nd_ns_target)) return; // Invalid target - char ipbuf[INET6_ADDRSTRLEN]; inet_ntop(AF_INET6, &req->nd_ns_target, ipbuf, sizeof(ipbuf)); - syslog(LOG_DEBUG, "Got a NS for %s", ipbuf); + syslog(LOG_DEBUG, "Got a NS for %s%%%s", ipbuf, iface->ifname); - uint8_t mac[6]; odhcpd_get_mac(iface, mac); if (!memcmp(ll->sll_addr, mac, sizeof(mac))) return; // Looped back struct interface *c; list_for_each_entry(c, &interfaces, head) - if (iface->ndp == RELAYD_RELAY && iface != c && + if (iface != c && c->ndp == MODE_RELAY && (ns_is_dad || !c->external)) ping6(&req->nd_ns_target, c); } - -void odhcpd_setup_route(const struct in6_addr *addr, int prefixlen, - const struct interface *iface, const struct in6_addr *gw, bool add) -{ - struct req { - struct nlmsghdr nh; - struct rtmsg rtm; - struct rtattr rta_dst; - struct in6_addr dst_addr; - struct rtattr rta_oif; - uint32_t ifindex; - struct rtattr rta_table; - uint32_t table; - struct rtattr rta_gw; - struct in6_addr gw; - } req = { - {sizeof(req), 0, NLM_F_REQUEST, ++rtnl_seqid, 0}, - {AF_INET6, prefixlen, 0, 0, 0, 0, 0, 0, 0}, - {sizeof(struct rtattr) + sizeof(struct in6_addr), RTA_DST}, - *addr, - {sizeof(struct rtattr) + sizeof(uint32_t), RTA_OIF}, - iface->ifindex, - {sizeof(struct rtattr) + sizeof(uint32_t), RTA_TABLE}, - RT_TABLE_MAIN, - {sizeof(struct rtattr) + sizeof(struct in6_addr), RTA_GATEWAY}, - IN6ADDR_ANY_INIT, - }; - - if (gw) - req.gw = *gw; - - if (add) { - req.nh.nlmsg_type = RTM_NEWROUTE; - req.nh.nlmsg_flags |= (NLM_F_CREATE | NLM_F_REPLACE); - req.rtm.rtm_protocol = RTPROT_STATIC; - req.rtm.rtm_scope = (gw) ? RT_SCOPE_UNIVERSE : RT_SCOPE_LINK; - req.rtm.rtm_type = RTN_UNICAST; - } else { - req.nh.nlmsg_type = RTM_DELROUTE; - req.rtm.rtm_scope = RT_SCOPE_NOWHERE; - } - - req.nh.nlmsg_len = (gw) ? sizeof(req) : offsetof(struct req, rta_gw); - send(rtnl_event.uloop.fd, &req, req.nh.nlmsg_len, MSG_DONTWAIT); -} - // Use rtnetlink to modify kernel routes static void setup_route(struct in6_addr *addr, struct interface *iface, bool add) { - char namebuf[INET6_ADDRSTRLEN]; - inet_ntop(AF_INET6, addr, namebuf, sizeof(namebuf)); - syslog(LOG_NOTICE, "%s about %s on %s", - (add) ? "Learned" : "Forgot", namebuf, iface->ifname); + char ipbuf[INET6_ADDRSTRLEN]; + + inet_ntop(AF_INET6, addr, ipbuf, sizeof(ipbuf)); + syslog(LOG_NOTICE, "%s about %s%s%%%s", + (add) ? "Learning" : "Forgetting", + iface->learn_routes ? "proxy routing for " : "", + ipbuf, iface->ifname); if (iface->learn_routes) - odhcpd_setup_route(addr, 128, iface, NULL, add); + netlink_setup_route(addr, 128, iface->ifindex, NULL, 1024, add); } - -// Handler for neighbor cache entries from the kernel. This is our source -// to learn and unlearn hosts on interfaces. -static void handle_rtnetlink(_unused void *addr, void *data, size_t len, - _unused struct interface *iface, _unused void *dest) +static void setup_addr_for_relaying(struct in6_addr *addr, struct interface *iface, bool add) { - bool dump_neigh = false; - struct in6_addr last_solicited = IN6ADDR_ANY_INIT; - - for (struct nlmsghdr *nh = data; NLMSG_OK(nh, len); - nh = NLMSG_NEXT(nh, len)) { - struct ndmsg *ndm = NLMSG_DATA(nh); - struct rtmsg *rtm = NLMSG_DATA(nh); - - bool is_addr = (nh->nlmsg_type == RTM_NEWADDR - || nh->nlmsg_type == RTM_DELADDR); - bool is_route = (nh->nlmsg_type == RTM_NEWROUTE - || nh->nlmsg_type == RTM_DELROUTE); - bool is_neigh = (nh->nlmsg_type == RTM_NEWNEIGH - || nh->nlmsg_type == RTM_DELNEIGH); - - // Family and ifindex are on the same offset for NEIGH and ADDR - if ((!is_addr && !is_route && !is_neigh) - || NLMSG_PAYLOAD(nh, 0) < sizeof(*ndm) - || ndm->ndm_family != AF_INET6) - continue; - - // Inform about a change in default route - if (is_route && rtm->rtm_dst_len == 0) - raise(SIGUSR1); - else if (is_route && rtm->rtm_dst_len == 128) - continue; + struct interface *c; + char ipbuf[INET6_ADDRSTRLEN]; - // Data to retrieve - size_t rta_offset = (is_route) ? sizeof(*rtm) : (is_addr) ? - sizeof(*ifa) : sizeof(*ndm); - uint16_t atype = (is_route) ? RTA_DST : (is_addr) ? IFA_ADDRESS : NDA_DST; - ssize_t alen = NLMSG_PAYLOAD(nh, rta_offset); - struct in6_addr *addr = NULL; - int *ifindex = (!is_route) ? &ndm->ndm_ifindex : NULL; - - for (struct rtattr *rta = (void*)(((uint8_t*)ndm) + rta_offset); - RTA_OK(rta, alen); rta = RTA_NEXT(rta, alen)) { - if (rta->rta_type == atype && - RTA_PAYLOAD(rta) >= sizeof(*addr)) { - addr = RTA_DATA(rta); - } else if (is_route && rta->rta_type == RTA_OIF && - RTA_PAYLOAD(rta) == sizeof(int)) { - ifindex = (int*)RTA_DATA(rta); - } else if (is_route && rta->rta_type == RTA_GATEWAY) { - ifindex = NULL; - break; - } - } + inet_ntop(AF_INET6, addr, ipbuf, sizeof(ipbuf)); - // Lookup interface - struct interface *iface = ifindex ? odhcpd_get_interface_by_index(*ifindex) : NULL; - if (!iface) + list_for_each_entry(c, &interfaces, head) { + if (iface == c || (c->ndp != MODE_RELAY && !add)) continue; - // Keep-alive neighbor entries for RA sending - if (nh->nlmsg_type == RTM_DELNEIGH && !(ndm->ndm_state & NUD_FAILED) && - addr && IN6_IS_ADDR_LINKLOCAL(addr) && iface->ra == RELAYD_SERVER) - ping6(addr, iface); + bool neigh_add = (c->ndp == MODE_RELAY ? add : false); - // Address not specified or unrelated - if (!addr || IN6_IS_ADDR_LINKLOCAL(addr) || - IN6_IS_ADDR_MULTICAST(addr)) - continue; - - // Check for states - bool add; - if (is_addr) - add = (nh->nlmsg_type == RTM_NEWADDR); + if (netlink_setup_proxy_neigh(addr, c->ifindex, neigh_add)) + syslog(LOG_DEBUG, "Failed to %s proxy neighbour entry %s%%%s", + neigh_add ? "add" : "delete", ipbuf, c->ifname); else - add = (nh->nlmsg_type == RTM_NEWNEIGH && (ndm->ndm_state & - (NUD_REACHABLE | NUD_STALE | NUD_DELAY | NUD_PROBE - | NUD_PERMANENT | NUD_NOARP))); - - if (iface->ndp == RELAYD_RELAY && !is_route) { - // Replay change to all neighbor cache - struct { - struct nlmsghdr nh; - struct ndmsg ndm; - struct nlattr nla_dst; - struct in6_addr dst; - } req = { - {sizeof(req), RTM_DELNEIGH, NLM_F_REQUEST, - ++rtnl_seqid, 0}, - {.ndm_family = AF_INET6, .ndm_flags = NTF_PROXY}, - {sizeof(struct nlattr) + sizeof(struct in6_addr), NDA_DST}, - *addr - }; - - if (ndm->ndm_flags & NTF_PROXY) { - // Dump & flush proxy entries - if (nh->nlmsg_type == RTM_NEWNEIGH) { - req.ndm.ndm_ifindex = iface->ifindex; - send(rtnl_event.uloop.fd, &req, sizeof(req), MSG_DONTWAIT); - setup_route(addr, iface, false); - dump_neigh = true; - } - } else if (add) { - struct interface *c; - list_for_each_entry(c, &interfaces, head) { - if (iface == c) - continue; - - if (c->ndp == RELAYD_RELAY) { - req.nh.nlmsg_type = RTM_NEWNEIGH; - req.nh.nlmsg_flags |= NLM_F_CREATE | NLM_F_REPLACE; - - req.ndm.ndm_ifindex = c->ifindex; - send(rtnl_event.uloop.fd, &req, sizeof(req), MSG_DONTWAIT); - } else { // Delete NDP cache from interfaces without relay - req.nh.nlmsg_type = RTM_DELNEIGH; - req.nh.nlmsg_flags &= ~(NLM_F_CREATE | NLM_F_REPLACE); - - req.ndm.ndm_ifindex = c->ifindex; - send(rtnl_event.uloop.fd, &req, sizeof(req), MSG_DONTWAIT); - } - } - - setup_route(addr, iface, true); - } else { - if (nh->nlmsg_type == RTM_NEWNEIGH) { - // might be locally originating - if (!IN6_ARE_ADDR_EQUAL(&last_solicited, addr)) { - last_solicited = *addr; - - struct interface *c; - list_for_each_entry(c, &interfaces, head) - if (iface->ndp == RELAYD_RELAY && iface != c && - !c->external == false) - ping6(addr, c); - } - } else { - struct interface *c; - list_for_each_entry(c, &interfaces, head) { - if (c->ndp == RELAYD_RELAY && iface != c) { - req.ndm.ndm_ifindex = c->ifindex; - send(rtnl_event.uloop.fd, &req, sizeof(req), MSG_DONTWAIT); - } - } - setup_route(addr, iface, false); - - // also: dump to add proxies back in case it moved elsewhere - dump_neigh = true; - } - } - } - - if (is_addr) { - if (iface->ra == RELAYD_SERVER) - raise(SIGUSR1); // Inform about a change in addresses - - if (iface->dhcpv6 == RELAYD_SERVER) - iface->ia_reconf = true; - } else if (is_route) { - if (iface->ndp == RELAYD_RELAY && iface->master) { - // Replay on-link route changes on all slave interfaces - nh->nlmsg_flags = NLM_F_REQUEST; - - if (nh->nlmsg_type == RTM_NEWROUTE) - nh->nlmsg_flags |= NLM_F_CREATE | NLM_F_REPLACE; - - struct interface *c; - list_for_each_entry(c, &interfaces, head) { - if (c->ndp == RELAYD_RELAY && !c->master) { - *ifindex = c->ifindex; - send(rtnl_event.uloop.fd, nh, nh->nlmsg_len, MSG_DONTWAIT); - } - } - } - } + syslog(LOG_DEBUG, "%s proxy neighbour entry %s%%%s", + neigh_add ? "Added" : "Deleted", ipbuf, c->ifname); } - - if (dump_neigh) - dump_neigh_table(false); }