#include <netinet/icmp6.h>
#include <netpacket/packet.h>
-#include <linux/rtnetlink.h>
#include <linux/filter.h>
-#include "router.h"
-#include "dhcpv6.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 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[] = {
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
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
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 = {
// 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 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)};
+ 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);
+ netlink_setup_route(addr, 128, iface->ifindex, NULL, 128, true);
odhcpd_send(ping_socket, &dest, &iov, 1, iface);
- odhcpd_setup_route(addr, 128, iface, NULL, 128, false);
+ netlink_setup_route(addr, 128, iface->ifindex, NULL, 128, false);
}
-
// Handle solicitations
static void handle_solicit(void *addr, void *data, size_t len,
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_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);
}
// 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);
-
- if (iface->learn_routes)
- odhcpd_setup_route(addr, 128, iface, NULL, 1024, add);
-}
-
-// compare prefixes
-static int prefixcmp(const void *va, const void *vb)
-{
- const struct odhcpd_ipaddr *a = va, *b = vb;
- uint32_t a_pref = ((a->addr.s6_addr[0] & 0xfe) != 0xfc) ? a->preferred : 1;
- uint32_t b_pref = ((b->addr.s6_addr[0] & 0xfe) != 0xfc) ? b->preferred : 1;
- return (a_pref < b_pref) ? 1 : (a_pref > b_pref) ? -1 : 0;
-}
-
-// Check address update
-static void check_updates(struct interface *iface)
-{
- struct odhcpd_ipaddr addr[8] = {{IN6ADDR_ANY_INIT, 0, 0, 0, 0}};
- time_t now = odhcpd_time();
- ssize_t len = odhcpd_get_interface_addresses(iface->ifindex, addr, 8);
-
- if (len < 0)
- return;
-
- qsort(addr, len, sizeof(*addr), prefixcmp);
-
- for (int i = 0; i < len; ++i) {
- addr[i].addr.s6_addr32[3] = 0;
-
- if (addr[i].preferred < UINT32_MAX - now)
- addr[i].preferred += now;
-
- if (addr[i].valid < UINT32_MAX - now)
- addr[i].valid += now;
- }
-
- 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, &iface->ia_addr[i].addr) ||
- (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);
-
- memcpy(iface->ia_addr, addr, len * sizeof(*addr));
- iface->ia_addr_len = len;
+ char ipbuf[INET6_ADDRSTRLEN];
- if (change)
- dhcpv6_ia_postupdate(iface, now);
+ 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 (change)
- raise(SIGUSR1);
+ if (iface->learn_routes)
+ 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)
- continue;
+ struct interface *c;
+ char ipbuf[INET6_ADDRSTRLEN];
- // Data to retrieve
- size_t rta_offset = (is_addr) ? sizeof(struct ifaddrmsg) : 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);
- }
- }
+ inet_ntop(AF_INET6, addr, ipbuf, sizeof(ipbuf));
- // Lookup interface
- struct interface *iface = odhcpd_get_interface_by_index(ndm->ndm_ifindex);
- if (!iface)
+ list_for_each_entry(c, &interfaces, head) {
+ if (iface == c || (c->ndp != MODE_RELAY && !add))
continue;
- // Address not specified or unrelated
- if (!addr || IN6_IS_ADDR_LINKLOCAL(addr) ||
- IN6_IS_ADDR_MULTICAST(addr))
- continue;
+ bool neigh_add = (c->ndp == MODE_RELAY ? add : false);
- // 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) {
- // 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) {
- check_updates(iface);
-
- if (iface->dhcpv6 == RELAYD_SERVER)
- iface->ia_reconf = true;
-
- if (iface->ndp == RELAYD_RELAY && iface->master) {
- // Replay address changes on all slave interfaces
- nh->nlmsg_flags = NLM_F_REQUEST;
-
- if (nh->nlmsg_type == RTM_NEWADDR)
- 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) {
- ndm->ndm_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);
}
projects / project / odhcpd.git / blobdiff