ubus: fix invalid ipv6-prefix json
[project/odhcpd.git] / src / ndp.c
index 45bb9db..6021db9 100644 (file)
--- a/src/ndp.c
+++ b/src/ndp.c
 #include <netinet/icmp6.h>
 #include <netpacket/packet.h>
 
-#include <linux/rtnetlink.h>
 #include <linux/filter.h>
-#include "router.h"
-#include "ndp.h"
+#include <linux/neighbour.h>
 
+#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[] = {
@@ -56,172 +52,230 @@ 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);
+       struct icmp6_filter filt;
+       int val = 2, ret = 0;
 
        // 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));
-                       return -1;
+               syslog(LOG_ERR, "socket(AF_INET6): %m");
+               ret = -1;
+               goto out;
        }
 
-       int val = 2;
-       setsockopt(ping_socket, IPPROTO_RAW, IPV6_CHECKSUM, &val, sizeof(val));
+       if (setsockopt(ping_socket, IPPROTO_RAW, IPV6_CHECKSUM,
+                               &val, sizeof(val)) < 0) {
+               syslog(LOG_ERR, "setsockopt(IPV6_CHECKSUM): %m");
+               ret = -1;
+               goto out;
+       }
 
        // This is required by RFC 4861
        val = 255;
-       setsockopt(ping_socket, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &val, sizeof(val));
-       setsockopt(ping_socket, IPPROTO_IPV6, IPV6_UNICAST_HOPS, &val, sizeof(val));
+       if (setsockopt(ping_socket, IPPROTO_IPV6, IPV6_MULTICAST_HOPS,
+                               &val, sizeof(val)) < 0) {
+               syslog(LOG_ERR, "setsockopt(IPV6_MULTICAST_HOPS): %m");
+               ret = -1;
+               goto out;
+       }
+
+       if (setsockopt(ping_socket, IPPROTO_IPV6, IPV6_UNICAST_HOPS,
+                               &val, sizeof(val)) < 0) {
+               syslog(LOG_ERR, "setsockopt(IPV6_UNICAST_HOPS): %m");
+               ret = -1;
+               goto out;
+       }
 
        // Filter all packages, we only want to send
-       struct icmp6_filter filt;
        ICMP6_FILTER_SETBLOCKALL(&filt);
-       setsockopt(ping_socket, IPPROTO_ICMPV6, ICMP6_FILTER, &filt, sizeof(filt));
-
+       if (setsockopt(ping_socket, IPPROTO_ICMPV6, ICMP6_FILTER,
+                               &filt, sizeof(filt)) < 0) {
+               syslog(LOG_ERR, "setsockopt(ICMP6_FILTER): %m");
+               ret = -1;
+               goto out;
+       }
 
-       // Netlink socket, continued...
-       group = RTNLGRP_NEIGH;
-       setsockopt(rtnl_event.uloop.fd, SOL_NETLINK, NETLINK_ADD_MEMBERSHIP, &group, sizeof(group));
-
-       return 0;
-}
+       netlink_add_netevent_handler(&ndp_netevent_handler);
 
+out:
+       if (ret < 0 && ping_socket > 0) {
+               close(ping_socket);
+               ping_socket = -1;
+       }
 
-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);
+       return ret;
 }
 
-
-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)
-                       write(procfd, "0\n", 2);
+               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 == MODE_RELAY) {
+               struct sockaddr_ll ll;
+               struct packet_mreq mreq;
 
-       if (enable && iface->ndp == RELAYD_RELAY) {
-               write(procfd, "1\n", 2);
-               close(procfd);
+               if (write(procfd, "1\n", 2) < 0) {}
 
-               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;
+               iface->ndp_event.uloop.fd = socket(AF_PACKET, SOCK_DGRAM | SOCK_CLOEXEC, htons(ETH_P_IPV6));
+               if (iface->ndp_event.uloop.fd < 0) {
+                       syslog(LOG_ERR, "socket(AF_PACKET): %m");
+                       ret = -1;
+                       goto out;
                }
 
 #ifdef PACKET_RECV_TYPE
                int pktt = 1 << PACKET_MULTICAST;
-               setsockopt(sock, SOL_PACKET, PACKET_RECV_TYPE, &pktt, sizeof(pktt));
+               if (setsockopt(iface->ndp_event.uloop.fd, SOL_PACKET, PACKET_RECV_TYPE,
+                               &pktt, sizeof(pktt)) < 0) {
+                       syslog(LOG_ERR, "setsockopt(PACKET_RECV_TYPE): %m");
+                       ret = -1;
+                       goto out;
+               }
 #endif
 
-               if (setsockopt(sock, SOL_SOCKET, SO_ATTACH_FILTER,
+               if (setsockopt(iface->ndp_event.uloop.fd, 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, "setsockopt(SO_ATTACH_FILTER): %m");
+                       ret = -1;
+                       goto out;
+               }
+
+               memset(&ll, 0, sizeof(ll));
+               ll.sll_family = AF_PACKET;
+               ll.sll_ifindex = iface->ifindex;
+               ll.sll_protocol = htons(ETH_P_IPV6);
+
+               if (bind(iface->ndp_event.uloop.fd, (struct sockaddr*)&ll, sizeof(ll)) < 0) {
+                       syslog(LOG_ERR, "bind(): %m");
+                       ret = -1;
+                       goto out;
+               }
+
+               memset(&mreq, 0, sizeof(mreq));
+               mreq.mr_ifindex = iface->ifindex;
+               mreq.mr_type = PACKET_MR_ALLMULTI;
+               mreq.mr_alen = ETH_ALEN;
+
+               if (setsockopt(iface->ndp_event.uloop.fd, SOL_PACKET, PACKET_ADD_MEMBERSHIP,
+                               &mreq, sizeof(mreq)) < 0) {
+                       syslog(LOG_ERR, "setsockopt(PACKET_ADD_MEMBERSHIP): %m");
+                       ret = -1;
+                       goto out;
                }
 
-               struct sockaddr_ll ll = {
-                       .sll_family = AF_PACKET,
-                       .sll_ifindex = iface->ifindex,
-                       .sll_protocol = htons(ETH_P_IPV6),
-                       .sll_hatype = 0,
-                       .sll_pkttype = 0,
-                       .sll_halen = 0,
-                       .sll_addr = {0},
-               };
-               bind(sock, (struct sockaddr*)&ll, sizeof(ll));
-
-               struct packet_mreq mreq = {iface->ifindex, PACKET_MR_ALLMULTI, ETH_ALEN, {0}};
-               setsockopt(sock, SOL_PACKET, PACKET_ADD_MEMBERSHIP, &mreq, sizeof(mreq));
-
-               iface->ndp_event.uloop.fd = sock;
                iface->ndp_event.handle_dgram = handle_solicit;
                odhcpd_register(&iface->ndp_event);
 
                // 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);
+
+ out:
+       if (ret < 0 && iface->ndp_event.uloop.fd > 0) {
+               close(iface->ndp_event.uloop.fd);
+               iface->ndp_event.uloop.fd = -1;
+       }
 
-       return 0;
+       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, 0};
-       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 +284,16 @@ 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))
@@ -247,241 +304,53 @@ 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 rtmsg *rtm = NLMSG_DATA(nh);
-               if ((nh->nlmsg_type == RTM_NEWROUTE ||
-                               nh->nlmsg_type == RTM_DELROUTE) &&
-                               rtm->rtm_dst_len == 0)
-                       raise(SIGUSR1); // Inform about a change in default route
-
-               struct ndmsg *ndm = NLMSG_DATA(nh);
-               struct ifaddrmsg *ifa = NLMSG_DATA(nh);
-               if (nh->nlmsg_type != RTM_NEWNEIGH
-                               && nh->nlmsg_type != RTM_DELNEIGH
-                               && nh->nlmsg_type != RTM_NEWADDR
-                               && nh->nlmsg_type != RTM_DELADDR)
-                       continue; // Unrelated message type
-               bool is_addr = (nh->nlmsg_type == RTM_NEWADDR
-                               || nh->nlmsg_type == RTM_DELADDR);
-
-               // Family and ifindex are on the same offset for NEIGH and ADDR
-               if (NLMSG_PAYLOAD(nh, 0) < sizeof(*ndm)
-                               || ndm->ndm_family != AF_INET6)
-                       continue; //
-
-               // Lookup interface
-               struct interface *iface;
-               if (!(iface = odhcpd_get_interface_by_index(ndm->ndm_ifindex)))
-                       continue;
-
-               // Data to retrieve
-               size_t rta_offset = (is_addr) ? sizeof(*ifa) : sizeof(*ndm);
-               uint16_t atype = (is_addr) ? IFA_ADDRESS : NDA_DST;
-               ssize_t alen = NLMSG_PAYLOAD(nh, rta_offset);
-               struct in6_addr *addr = 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);
-
-               // 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);
-               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) {
-                       // 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
+       struct interface *c;
+       char ipbuf[INET6_ADDRSTRLEN];
 
-                       if (iface->dhcpv6 == RELAYD_SERVER)
-                               iface->ia_reconf = true;
+       inet_ntop(AF_INET6, addr, ipbuf, sizeof(ipbuf));
 
-                       if (iface->ndp == RELAYD_RELAY && iface->master) {
-                               // Replay address changes on all slave interfaces
-                               nh->nlmsg_flags = NLM_F_REQUEST;
+       list_for_each_entry(c, &interfaces, head) {
+               if (iface == c || (c->ndp != MODE_RELAY && !add))
+                       continue;
 
-                               if (nh->nlmsg_type == RTM_NEWADDR)
-                                       nh->nlmsg_flags |= NLM_F_CREATE | NLM_F_REPLACE;
+               bool neigh_add = (c->ndp == MODE_RELAY ? add : false);
 
-                               struct interface *c;
-                               list_for_each_entry(c, &interfaces, head) {
-                                       if (c->ndp == RELAYD_RELAY && !c->master) {
-                                               ifa->ifa_index = c->ifindex;
-                                               send(rtnl_event.uloop.fd, nh, nh->nlmsg_len, MSG_DONTWAIT);
-                                       }
-                               }
-                       }
-               }
+               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
+                       syslog(LOG_DEBUG, "%s proxy neighbour entry %s%%%s",
+                               neigh_add ? "Added" : "Deleted", ipbuf, c->ifname);
        }
-
-       if (dump_neigh)
-               dump_neigh_table(false);
 }