#include <signal.h>
#include <errno.h>
+#include <fcntl.h>
+#include <unistd.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#include <net/ethernet.h>
#include <linux/rtnetlink.h>
#include <linux/filter.h>
-#include "router.h"
-#include "ndp.h"
+#include <netlink/msg.h>
+#include <netlink/socket.h>
+#include <netlink/attr.h>
+#include "dhcpv6.h"
+#include "odhcpd.h"
+
+struct event_socket {
+ struct odhcpd_event ev;
+ struct nl_sock *sock;
+ int sock_bufsize;
+};
static void handle_solicit(void *addr, void *data, size_t len,
- struct interface *iface);
-static void handle_rtnetlink(void *addr, void *data, size_t len,
- struct interface *iface);
-static struct ndp_neighbor* find_neighbor(struct in6_addr *addr, bool strict);
-static void modify_neighbor(struct in6_addr *addr, struct interface *iface,
- bool add);
-static ssize_t ping6(struct in6_addr *addr,
- const struct interface *iface);
-
-static struct list_head neighbors = LIST_HEAD_INIT(neighbors);
-static size_t neighbor_count = 0;
-static uint32_t rtnl_seqid = 0;
+ struct interface *iface, void *dest);
+static void handle_rtnl_event(struct odhcpd_event *ev);
+static int cb_rtnl_valid(struct nl_msg *msg, void *arg);
+static void catch_rtnl_err(struct odhcpd_event *e, int error);
static int ping_socket = -1;
-static struct odhcpd_event ndp_event = {{.fd = -1}, handle_solicit};
-static struct odhcpd_event rtnl_event = {{.fd = -1}, handle_rtnetlink};
-
+static struct event_socket rtnl_event = {
+ .ev = {
+ .uloop = {.fd = - 1, },
+ .handle_dgram = NULL,
+ .handle_error = catch_rtnl_err,
+ .recv_msgs = handle_rtnl_event,
+ },
+ .sock = NULL,
+ .sock_bufsize = 133120,
+};
// Filter ICMPv6 messages of type neighbor soliciation
static struct sock_filter bpf[] = {
// Initialize NDP-proxy
int init_ndp(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));
-
- // 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}
- };
- send(rtnl_event.uloop.fd, &req2, sizeof(req2), MSG_DONTWAIT);
- odhcpd_register(&rtnl_event);
+ int val = 2;
+ rtnl_event.sock = odhcpd_create_nl_socket(NETLINK_ROUTE);
+ if (!rtnl_event.sock)
+ goto err;
- // Create socket for intercepting NDP
- int sock = socket(AF_PACKET, SOCK_DGRAM | SOCK_CLOEXEC | SOCK_NONBLOCK,
- htons(ETH_P_ALL)); // ETH_P_ALL for ingress + egress
- if (sock < 0) {
- syslog(LOG_ERR, "Unable to open packet socket: %s",
- strerror(errno));
- return -1;
- }
+ rtnl_event.ev.uloop.fd = nl_socket_get_fd(rtnl_event.sock);
- 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;
- }
+ if (nl_socket_set_buffer_size(rtnl_event.sock, rtnl_event.sock_bufsize, 0))
+ goto err;
- ndp_event.uloop.fd = sock;
- odhcpd_register(&ndp_event);
+ nl_socket_disable_seq_check(rtnl_event.sock);
+
+ nl_socket_modify_cb(rtnl_event.sock, NL_CB_VALID, NL_CB_CUSTOM,
+ cb_rtnl_valid, NULL);
+
+ // Receive IPv4 address, IPv6 address, IPv6 routes and neighbor events
+ if (nl_socket_add_memberships(rtnl_event.sock, RTNLGRP_IPV4_IFADDR,
+ RTNLGRP_IPV6_IFADDR, RTNLGRP_IPV6_ROUTE,
+ RTNLGRP_NEIGH, 0))
+ goto err;
+
+ odhcpd_register(&rtnl_event.ev);
// 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;
+ }
- int val = 2;
setsockopt(ping_socket, IPPROTO_RAW, IPV6_CHECKSUM, &val, sizeof(val));
// This is required by RFC 4861
ICMP6_FILTER_SETBLOCKALL(&filt);
setsockopt(ping_socket, IPPROTO_ICMPV6, ICMP6_FILTER, &filt, sizeof(filt));
+ return 0;
+
+err:
+ if (rtnl_event.sock) {
+ nl_socket_free(rtnl_event.sock);
+ rtnl_event.sock = NULL;
+ rtnl_event.ev.uloop.fd = -1;
+ }
- // Netlink socket, continued...
- group = RTNLGRP_NEIGH;
- setsockopt(rtnl_event.uloop.fd, SOL_NETLINK, NETLINK_ADD_MEMBERSHIP, &group, sizeof(group));
+ return -1;
+}
- // Synthesize initial neighbor events
- 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}
+static void dump_neigh_table(const bool proxy)
+{
+ struct nl_msg *msg;
+ struct ndmsg ndm = {
+ .ndm_family = AF_INET6,
+ .ndm_flags = proxy ? NTF_PROXY : 0,
};
- send(rtnl_event.uloop.fd, &req, sizeof(req), MSG_DONTWAIT);
- return 0;
+ msg = nlmsg_alloc_simple(RTM_GETNEIGH, NLM_F_REQUEST | NLM_F_DUMP);
+ if (!msg)
+ return;
+
+ nlmsg_append(msg, &ndm, sizeof(ndm), 0);
+
+ nl_send_auto_complete(rtnl_event.sock, msg);
+
+ nlmsg_free(msg);
}
+static void dump_addr_table(bool v6)
+{
+ struct nl_msg *msg;
+ struct ifaddrmsg ifa = {
+ .ifa_family = v6 ? AF_INET6 : AF_INET,
+ };
+
+ msg = nlmsg_alloc_simple(RTM_GETADDR, NLM_F_REQUEST | NLM_F_DUMP);
+ if (!msg)
+ return;
+
+ nlmsg_append(msg, &ifa, sizeof(ifa), 0);
+
+ nl_send_auto_complete(rtnl_event.sock, msg);
+
+ nlmsg_free(msg);
+}
int setup_ndp_interface(struct interface *iface, bool enable)
{
- struct packet_mreq mreq = {iface->ifindex, PACKET_MR_ALLMULTI, ETH_ALEN, {0}};
- setsockopt(ndp_event.uloop.fd, SOL_PACKET, PACKET_DROP_MEMBERSHIP, &mreq, sizeof(mreq));
-
- struct ndp_neighbor *c, *n;
- list_for_each_entry_safe(c, n, &neighbors, head)
- if (c->iface == iface && (c->timeout == 0 || iface->ndp != RELAYD_RELAY || !enable))
- modify_neighbor(&c->addr, c->iface, false);
-
- if (enable && iface->ndp == RELAYD_RELAY) {
- setsockopt(ndp_event.uloop.fd, SOL_PACKET, PACKET_ADD_MEMBERSHIP, &mreq, sizeof(mreq));
-
- if (iface->static_ndp_len) {
- char *entry = alloca(iface->static_ndp_len), *saveptr;
- if (!entry) {
- syslog(LOG_ERR, "Alloca failed for static NDP list");
- return -1;
- }
- memcpy(entry, iface->static_ndp, iface->static_ndp_len);
-
- for (entry = strtok_r(entry, " ", &saveptr); entry; entry = strtok_r(NULL, " ", &saveptr)) {
- struct ndp_neighbor *n = malloc(sizeof(*n));
- if (!n) {
- syslog(LOG_ERR, "Malloc failed for static NDP-prefix %s", entry);
- return -1;
- }
-
- n->iface = iface;
- n->timeout = 0;
-
- char ipbuf[INET6_ADDRSTRLEN];
- if (sscanf(entry, "%45s/%hhu", ipbuf, &n->len) < 2
- || n->len > 128 || inet_pton(AF_INET6, ipbuf, &n->addr) != 1) {
- syslog(LOG_ERR, "Invalid static NDP-prefix %s", entry);
- return -1;
- }
-
- list_add(&n->head, &neighbors);
- }
+ 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);
+ 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 != MODE_RELAY)
+ if (write(procfd, "0\n", 2) < 0) {}
+
+ dump_neigh = true;
+ }
+
+ if (enable && iface->ndp == MODE_RELAY) {
+ 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));
+ ret = -1;
+ goto out;
+ }
+
+#ifdef PACKET_RECV_TYPE
+ int pktt = 1 << PACKET_MULTICAST;
+ setsockopt(sock, SOL_PACKET, PACKET_RECV_TYPE, &pktt, sizeof(pktt));
+#endif
+
+ if (setsockopt(sock, SOL_SOCKET, SO_ATTACH_FILTER,
+ &bpf_prog, sizeof(bpf_prog))) {
+ syslog(LOG_ERR, "Failed to set BPF: %s", strerror(errno));
+ 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);
+ else
+ dump_neigh = false;
}
- return 0;
+ if (dump_neigh)
+ dump_neigh_table(true);
+
+out:
+ if (procfd >= 0)
+ close(procfd);
+
+ return ret;
}
// 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);
+
+ odhcpd_setup_route(addr, 128, iface, NULL, 128, true);
+ odhcpd_send(ping_socket, &dest, &iov, 1, iface);
+ odhcpd_setup_route(addr, 128, iface, NULL, 128, false);
+}
// Handle solicitations
static void handle_solicit(void *addr, void *data, size_t len,
- struct interface *iface)
+ struct interface *iface, _unused void *dest)
{
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))
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_NOTICE, "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)) &&
- ll->sll_pkttype != PACKET_OUTGOING)
+ if (!memcmp(ll->sll_addr, mac, sizeof(mac)))
return; // Looped back
- time_t now = time(NULL);
-
- struct ndp_neighbor *n = find_neighbor(&req->nd_ns_target, false);
- if (n && (n->iface || abs(n->timeout - now) < 5)) {
- syslog(LOG_NOTICE, "%s is on %s", ipbuf,
- (n->iface) ? n->iface->ifname : "<pending>");
- if (!n->iface || n->iface == iface)
- return;
-
- // Found on other interface, answer with advertisement
- struct {
- struct nd_neighbor_advert body;
- struct nd_opt_hdr opt_ll_hdr;
- uint8_t mac[6];
- } advert = {
- .body = {
- .nd_na_hdr = {ND_NEIGHBOR_ADVERT,
- 0, 0, {{0}}},
- .nd_na_target = req->nd_ns_target,
- },
- .opt_ll_hdr = {ND_OPT_TARGET_LINKADDR, 1},
- };
-
- memcpy(advert.mac, mac, sizeof(advert.mac));
- advert.body.nd_na_flags_reserved = ND_NA_FLAG_ROUTER |
- ND_NA_FLAG_SOLICITED;
-
- struct sockaddr_in6 dest = {AF_INET6, 0, 0, ALL_IPV6_NODES, 0};
- if (!ns_is_dad) // If not DAD, then unicast to source
- dest.sin6_addr = ip6->ip6_src;
-
- // 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));
- struct iovec iov = {&advert, sizeof(advert)};
- odhcpd_send(ping_socket, &dest, &iov, 1, iface);
- } else {
- // Send echo to all other interfaces to see where target is on
- // This will trigger neighbor discovery which is what we want.
- // We will observe the neighbor cache to see results.
-
- ssize_t sent = 0;
- struct interface *c;
- list_for_each_entry(c, &interfaces, head)
- if (iface->ndp == RELAYD_RELAY && iface != c &&
- (!ns_is_dad || !c->external == false))
- sent += ping6(&req->nd_ns_target, c);
-
- if (sent > 0) // Sent a ping, add pending neighbor entry
- modify_neighbor(&req->nd_ns_target, NULL, true);
- }
+ struct interface *c;
+ list_for_each_entry(c, &interfaces, head)
+ 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)
+// Use rtnetlink to modify kernel routes
+static void setup_route(struct in6_addr *addr, struct interface *iface, 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,
- };
+ char ipbuf[INET6_ADDRSTRLEN];
- 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_BOOT;
- 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;
- }
+ inet_ntop(AF_INET6, addr, ipbuf, sizeof(ipbuf));
+ syslog(LOG_NOTICE, "%s about %s%%%s",
+ (add) ? "Learned" : "Forgot", ipbuf, iface->ifname);
- size_t reqlen = (gw) ? sizeof(req) : offsetof(struct req, rta_gw);
- send(rtnl_event.uloop.fd, &req, reqlen, MSG_DONTWAIT);
+ if (iface->learn_routes)
+ odhcpd_setup_route(addr, 128, iface, NULL, 1024, add);
}
-// Use rtnetlink to modify kernel routes
-static void setup_route(struct in6_addr *addr, struct interface *iface,
- bool add)
+// Check address update
+static void check_addr_updates(struct interface *iface)
{
- 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) ? iface->ifname : "<pending>");
+ struct odhcpd_ipaddr *addr = NULL;
+ ssize_t len = odhcpd_get_interface_addresses(iface->ifindex, false, &addr);
- if (!iface || !iface->learn_routes)
+ if (len < 0)
return;
- odhcpd_setup_route(addr, 128, iface, NULL, add);
-}
+ bool change = len != (ssize_t)iface->addr4_len;
+ for (ssize_t i = 0; !change && i < len; ++i)
+ if (addr[i].addr.in.s_addr != iface->addr4[i].addr.in.s_addr)
+ change = true;
-static void free_neighbor(struct ndp_neighbor *n)
-{
- setup_route(&n->addr, n->iface, false);
- list_del(&n->head);
- free(n);
- --neighbor_count;
+ free(iface->addr4);
+ iface->addr4 = addr;
+ iface->addr4_len = len;
}
-
-static bool match_neighbor(struct ndp_neighbor *n, struct in6_addr *addr)
+// Check v6 address update
+static void check_addr6_updates(struct interface *iface)
{
- if (n->len <= 32)
- return ntohl(n->addr.s6_addr32[0]) >> (32 - n->len) ==
- ntohl(addr->s6_addr32[0]) >> (32 - n->len);
-
- if (n->addr.s6_addr32[0] != addr->s6_addr32[0])
- return false;
+ struct odhcpd_ipaddr *addr = NULL;
+ ssize_t len = odhcpd_get_interface_addresses(iface->ifindex, true, &addr);
- if (n->len <= 64)
- return ntohl(n->addr.s6_addr32[1]) >> (64 - n->len) ==
- ntohl(addr->s6_addr32[1]) >> (64 - n->len);
+ if (len < 0)
+ return;
- if (n->addr.s6_addr32[1] != addr->s6_addr32[1])
- return false;
+ bool change = len != (ssize_t)iface->ia_addr_len;
+ for (ssize_t i = 0; !change && i < len; ++i)
+ if (!IN6_ARE_ADDR_EQUAL(&addr[i].addr.in6, &iface->ia_addr[i].addr.in6) ||
+ (addr[i].preferred > 0) != (iface->ia_addr[i].preferred > 0) ||
+ addr[i].valid < iface->ia_addr[i].valid ||
+ addr[i].preferred < iface->ia_addr[i].preferred)
+ change = true;
+
+ if (change)
+ dhcpv6_ia_preupdate(iface);
+
+ free(iface->ia_addr);
+ iface->ia_addr = addr;
+ iface->ia_addr_len = len;
+
+ if (change) {
+ dhcpv6_ia_postupdate(iface);
+ syslog(LOG_INFO, "Raising SIGUSR1 due to address change on %s", iface->ifname);
+ raise(SIGUSR1);
+ }
+}
- if (n->len <= 96)
- return ntohl(n->addr.s6_addr32[2]) >> (96 - n->len) ==
- ntohl(addr->s6_addr32[2]) >> (96 - n->len);
+static void setup_addr_for_relaying(struct in6_addr *addr, struct interface *iface, bool add)
+{
+ struct interface *c;
+ char ipbuf[INET6_ADDRSTRLEN];
- if (n->addr.s6_addr32[2] != addr->s6_addr32[2])
- return false;
+ inet_ntop(AF_INET6, addr, ipbuf, sizeof(ipbuf));
- return ntohl(n->addr.s6_addr32[3]) >> (128 - n->len) ==
- ntohl(addr->s6_addr32[3]) >> (128 - n->len);
-}
+ list_for_each_entry(c, &interfaces, head) {
+ if (iface == c || (c->ndp != MODE_RELAY && !add))
+ continue;
+ bool neigh_add = (c->ndp == MODE_RELAY ? add : false);
-static struct ndp_neighbor* find_neighbor(struct in6_addr *addr, bool strict)
-{
- time_t now = time(NULL);
- struct ndp_neighbor *n, *e;
- list_for_each_entry_safe(n, e, &neighbors, head) {
- if ((!strict && match_neighbor(n, addr)) ||
- (n->len == 128 && IN6_ARE_ADDR_EQUAL(&n->addr, addr)))
- return n;
-
- if (!n->iface && abs(n->timeout - now) >= 5)
- free_neighbor(n);
+ if (odhcpd_setup_proxy_neigh(addr, c, 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);
}
- return NULL;
}
-
-// Modified our own neighbor-entries
-static void modify_neighbor(struct in6_addr *addr,
- struct interface *iface, bool add)
+static void handle_rtnl_event(struct odhcpd_event *e)
{
- if (!addr || (void*)addr == (void*)iface)
- return;
+ struct event_socket *ev_sock = container_of(e, struct event_socket, ev);
- struct ndp_neighbor *n = find_neighbor(addr, true);
- if (!add) { // Delete action
- if (n && (!n->iface || n->iface == iface))
- free_neighbor(n);
- } else if (!n) { // No entry yet, add one if possible
- if (neighbor_count >= NDP_MAX_NEIGHBORS ||
- !(n = malloc(sizeof(*n))))
- return;
-
- n->len = 128;
- n->addr = *addr;
- n->iface = iface;
- if (!n->iface)
- time(&n->timeout);
- list_add(&n->head, &neighbors);
- ++neighbor_count;
- setup_route(addr, n->iface, add);
- } else if (n->iface == iface) {
- if (!n->iface)
- time(&n->timeout);
- } else if (iface && (!n->iface ||
- (!iface->external && n->iface->external))) {
- setup_route(addr, n->iface, false);
- n->iface = iface;
- setup_route(addr, n->iface, add);
- }
- // TODO: In case a host switches interfaces we might want
- // to set its old neighbor entry to NUD_STALE and ping it
- // on the old interface to confirm if the MACs match.
+ nl_recvmsgs_default(ev_sock->sock);
}
// 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)
+static int cb_rtnl_valid(struct nl_msg *msg, _unused void *arg)
{
- 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;
+ struct nlmsghdr *hdr = nlmsg_hdr(msg);
+ struct in6_addr *addr6 = NULL;
+ struct interface *iface = NULL;
+ bool add = false;
+ char ipbuf[INET6_ADDRSTRLEN];
- // 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;
+ switch (hdr->nlmsg_type) {
+ case RTM_NEWROUTE:
+ case RTM_DELROUTE: {
+ struct rtmsg *rtm = nlmsg_data(hdr);
- // 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 (!nlmsg_valid_hdr(hdr, sizeof(*rtm)) ||
+ rtm->rtm_family != AF_INET6)
+ return NL_SKIP;
+
+ if (rtm->rtm_dst_len == 0) {
+ syslog(LOG_INFO, "Raising SIGUSR1 due to default route change");
+ raise(SIGUSR1);
+ }
+ return NL_OK;
+ }
+
+ case RTM_NEWADDR:
+ add = true;
+ /* fall through */
+ case RTM_DELADDR: {
+ struct ifaddrmsg *ifa = nlmsg_data(hdr);
+ struct nlattr *nla[__IFA_MAX];
+
+ if (!nlmsg_valid_hdr(hdr, sizeof(*ifa)) ||
+ (ifa->ifa_family != AF_INET6 &&
+ ifa->ifa_family != AF_INET))
+ return NL_SKIP;
+
+ iface = odhcpd_get_interface_by_index(ifa->ifa_index);
+ if (!iface)
+ return NL_SKIP;
+
+ nlmsg_parse(hdr, sizeof(*ifa), nla, __IFA_MAX - 1, NULL);
- if (iface->ndp == RELAYD_RELAY)
- modify_neighbor(addr, iface, add);
+ if (ifa->ifa_family == AF_INET6) {
+ if (!nla[IFA_ADDRESS])
+ return NL_SKIP;
- if (is_addr && iface->ra == RELAYD_SERVER)
- raise(SIGUSR1); // Inform about a change in addresses
+ addr6 = nla_data(nla[IFA_ADDRESS]);
+ if (!addr6 || IN6_IS_ADDR_LINKLOCAL(addr6) ||
+ IN6_IS_ADDR_MULTICAST(addr6))
+ return NL_SKIP;
- if (is_addr && iface->dhcpv6 == RELAYD_SERVER)
- iface->ia_reconf = true;
+ inet_ntop(AF_INET6, addr6, ipbuf, sizeof(ipbuf));
+ syslog(LOG_DEBUG, "Netlink %s %s%%%s", add ? "newaddr" : "deladdr",
+ ipbuf, iface->ifname);
- if (iface->ndp == RELAYD_RELAY && is_addr && iface->master) {
- // Replay address changes on all slave interfaces
- nh->nlmsg_flags = NLM_F_REQUEST;
+ check_addr6_updates(iface);
- if (nh->nlmsg_type == RTM_NEWADDR)
- nh->nlmsg_flags |= NLM_F_CREATE | NLM_F_REPLACE;
+ if (iface->ndp != MODE_RELAY)
+ break;
+
+ /* handle the relay logic below */
+ setup_addr_for_relaying(addr6, iface, add);
+
+ if (!add)
+ dump_neigh_table(false);
+ } else {
+ if (!nla[IFA_LOCAL])
+ return NL_SKIP;
+
+ struct in_addr *addr = nla_data(nla[IFA_ADDRESS]);
+
+ inet_ntop(AF_INET, addr, ipbuf, sizeof(ipbuf));
+ syslog(LOG_DEBUG, "Netlink %s %s%%%s", add ? "newaddr" : "deladdr",
+ ipbuf, iface->ifname);
+
+ check_addr_updates(iface);
+ }
+ break;
+ }
- 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);
- }
+ case RTM_NEWNEIGH:
+ add = true;
+ /* fall through */
+ case RTM_DELNEIGH: {
+ struct ndmsg *ndm = nlmsg_data(hdr);
+ struct nlattr *nla[__NDA_MAX];
+
+ if (!nlmsg_valid_hdr(hdr, sizeof(*ndm)) ||
+ ndm->ndm_family != AF_INET6)
+ return NL_SKIP;
+
+ iface = odhcpd_get_interface_by_index(ndm->ndm_ifindex);
+ if (!iface || iface->ndp != MODE_RELAY)
+ return (iface ? NL_OK : NL_SKIP);
+
+ nlmsg_parse(hdr, sizeof(*ndm), nla, __NDA_MAX - 1, NULL);
+ if (!nla[NDA_DST])
+ return NL_SKIP;
+
+ addr6 = nla_data(nla[NDA_DST]);
+ if (!addr6 || IN6_IS_ADDR_LINKLOCAL(addr6) ||
+ IN6_IS_ADDR_MULTICAST(addr6))
+ return NL_SKIP;
+
+ inet_ntop(AF_INET6, addr6, ipbuf, sizeof(ipbuf));
+ syslog(LOG_DEBUG, "Netlink %s %s%%%s", true ? "newneigh" : "delneigh",
+ ipbuf, iface->ifname);
+
+ if (ndm->ndm_flags & NTF_PROXY) {
+ /* Dump and flush proxy entries */
+ if (hdr->nlmsg_type == RTM_NEWNEIGH) {
+ odhcpd_setup_proxy_neigh(addr6, iface, false);
+ setup_route(addr6, iface, false);
+ dump_neigh_table(false);
}
+
+ return NL_OK;
}
- /* TODO: See if this is required for optimal operation
- // Keep neighbor entries alive so we don't loose routes
- if (add && (ndm->ndm_state & NUD_STALE))
- ping6(addr, iface);
- */
+ if (add && !(ndm->ndm_state &
+ (NUD_REACHABLE | NUD_STALE | NUD_DELAY | NUD_PROBE |
+ NUD_PERMANENT | NUD_NOARP)))
+ return NL_OK;
+
+ setup_addr_for_relaying(addr6, iface, add);
+ setup_route(addr6, iface, add);
+
+ if (!add)
+ dump_neigh_table(false);
+ break;
}
+
+ default:
+ return NL_SKIP;
+ }
+
+ return NL_OK;
+}
+
+static void catch_rtnl_err(struct odhcpd_event *e, int error)
+{
+ struct event_socket *ev_sock = container_of(e, struct event_socket, ev);
+
+ if (error != ENOBUFS)
+ goto err;
+
+ /* Double netlink event buffer size */
+ ev_sock->sock_bufsize *= 2;
+
+ if (nl_socket_set_buffer_size(ev_sock->sock, ev_sock->sock_bufsize, 0))
+ goto err;
+
+ dump_addr_table(true);
+ return;
+
+err:
+ odhcpd_deregister(e);
}
projects / project / odhcpd.git / blobdiff