router: add syslog debug tracing for trouble shooting

[project/odhcpd.git] / src / router.c

diff --git a/src/router.c b/src/router.c
index d7452f5..5d254fd 100644 (file)
--- a/src/router.c
+++ b/src/router.c
@@ -20,6 +20,7 @@
 #include <stdlib.h>
 #include <unistd.h>
 #include <stdbool.h>
+#include <arpa/inet.h>
 #include <net/route.h>
 
 #include "router.h"
@@ -34,7 +35,7 @@ static void handle_icmpv6(void *addr, void *data, size_t len,
 static void trigger_router_advert(struct uloop_timeout *event);
 static void sigusr1_refresh(int signal);
 
-static struct odhcpd_event router_event = {{.fd = -1}, handle_icmpv6};
+static struct odhcpd_event router_event = {{.fd = -1}, handle_icmpv6, NULL};
 
 static FILE *fp_route = NULL;
 #define RA_IOV_LEN 6
@@ -99,6 +100,9 @@ int setup_router_interface(struct interface *iface, bool enable)
        uloop_timeout_cancel(&iface->timer_rs);
        iface->timer_rs.cb = NULL;
 
+       if (iface->ifindex <= 0)
+               return -1;
+
        setsockopt(router_event.uloop.fd, IPPROTO_IPV6, IPV6_DROP_MEMBERSHIP,
                        &all_nodes, sizeof(all_nodes));
        setsockopt(router_event.uloop.fd, IPPROTO_IPV6, IPV6_DROP_MEMBERSHIP,
@@ -244,34 +248,44 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
        odhcpd_get_mac(iface, adv.lladdr.data);
 
        // If not currently shutting down
-       struct odhcpd_ipaddr *addrs = NULL;
+       struct odhcpd_ipaddr addrs[RELAYD_MAX_ADDRS];
        ssize_t ipcnt = 0;
        int64_t minvalid = INT64_MAX;
-       int64_t maxvalid = 0;
 
        // If not shutdown
        if (iface->timer_rs.cb) {
-               addrs = iface->ia_addr;
                ipcnt = iface->ia_addr_len;
+               memcpy(addrs, iface->ia_addr, ipcnt * sizeof(*addrs));
 
                // Check default route
-               if (parse_routes(addrs, ipcnt))
-                       adv.h.nd_ra_router_lifetime = htons(1);
                if (iface->default_router > 1)
                        adv.h.nd_ra_router_lifetime = htons(iface->default_router);
+               else if (parse_routes(addrs, ipcnt))
+                       adv.h.nd_ra_router_lifetime = htons(1);
+
+               syslog(LOG_DEBUG, "Initial router lifetime %d, %d address(es) available",
+                               ntohs(adv.h.nd_ra_router_lifetime), ipcnt);
        }
 
        // Construct Prefix Information options
        size_t cnt = 0;
 
-       struct in6_addr dns_pref = IN6ADDR_ANY_INIT, *dns_addr = &dns_pref;
-       uint32_t dns_time = 0;
+       struct in6_addr dns_pref, *dns_addr = &dns_pref;
        size_t dns_cnt = 1;
 
+       odhcpd_get_linklocal_interface_address(iface->ifindex, &dns_pref);
+
        for (ssize_t i = 0; i < ipcnt; ++i) {
                struct odhcpd_ipaddr *addr = &addrs[i];
-               if (addr->prefix > 96 || addr->valid <= (uint32_t)now)
-                       continue; // Address not suitable
+
+               if (addr->prefix > 96 || addr->valid <= (uint32_t)now) {
+                       char namebuf[INET6_ADDRSTRLEN];
+
+                       inet_ntop(AF_INET6, addr, namebuf, sizeof(namebuf));
+                       syslog(LOG_DEBUG, "Address %s (prefix %d, valid %u) not suitable",
+                                       namebuf, addr->prefix, addr->valid);
+                       continue;
+               }
 
                struct nd_opt_prefix_info *p = NULL;
                for (size_t i = 0; i < cnt; ++i) {
@@ -292,12 +306,16 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
                                minvalid > 1000LL * TIME_LEFT(addr->valid, now))
                        minvalid = 1000LL * TIME_LEFT(addr->valid, now);
 
-               if (maxvalid < 1000LL * TIME_LEFT(addr->valid, now))
-                       maxvalid = 1000LL * TIME_LEFT(addr->valid, now);
-
+               uint32_t this_lifetime = TIME_LEFT(addr->valid, now);
+               if (this_lifetime > UINT16_MAX)
+                       this_lifetime = UINT16_MAX;
                if (((addr->addr.s6_addr[0] & 0xfe) != 0xfc || iface->default_router)
-                               && ntohs(adv.h.nd_ra_router_lifetime) < TIME_LEFT(addr->valid, now))
-                       adv.h.nd_ra_router_lifetime = htons(TIME_LEFT(addr->valid, now));
+                               && adv.h.nd_ra_router_lifetime
+                               && ntohs(adv.h.nd_ra_router_lifetime) < this_lifetime) {
+                       adv.h.nd_ra_router_lifetime = htons(this_lifetime);
+
+                       syslog(LOG_DEBUG, "Updating router lifetime to %d", this_lifetime);
+               }
 
                odhcpd_bmemcpy(&p->nd_opt_pi_prefix, &addr->addr,
                                (iface->ra_advrouter) ? 128 : addr->prefix);
@@ -314,15 +332,11 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
                p->nd_opt_pi_valid_time = htonl(TIME_LEFT(addr->valid, now));
                if (addr->preferred > (uint32_t)now)
                        p->nd_opt_pi_preferred_time = htonl(TIME_LEFT(addr->preferred, now));
-
-
-               if (TIME_LEFT(addr->preferred, now) > dns_time) {
-                       dns_time = TIME_LEFT(addr->preferred, now);
-                       dns_pref = addr->addr;
-               }
+               else if (addr->valid - now < 7200)
+                       p->nd_opt_pi_valid_time = 0;
        }
 
-       if (!iface->default_router && ntohs(adv.h.nd_ra_router_lifetime) == 1) {
+       if (!iface->default_router && adv.h.nd_ra_router_lifetime == htons(1)) {
                syslog(LOG_WARNING, "A default route is present but there is no public prefix "
                                "on %s thus we don't announce a default route!", iface->ifname);
                adv.h.nd_ra_router_lifetime = 0;
@@ -332,7 +346,6 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
        if (iface->dns_cnt > 0) {
                dns_addr = iface->dns;
                dns_cnt = iface->dns_cnt;
-               dns_time = 0;
        }
 
        if (!dns_addr || IN6_IS_ADDR_UNSPECIFIED(dns_addr))
@@ -344,7 +357,7 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
                uint8_t pad;
                uint8_t pad2;
                uint32_t lifetime;
-       } dns = {ND_OPT_RECURSIVE_DNS, (1 + (2 * dns_cnt)), 0, 0, htonl(dns_time)};
+       } dns = {ND_OPT_RECURSIVE_DNS, (1 + (2 * dns_cnt)), 0, 0, 0};
 
 
 
@@ -437,10 +450,8 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
 
        minival = (maxival * 3) / 4;
 
-       search->lifetime = htonl(maxvalid / 1000);
-
-       if (!dns.lifetime)
-               dns.lifetime = search->lifetime;
+       search->lifetime = htonl(maxival / 100);
+       dns.lifetime = search->lifetime;
 
        odhcpd_urandom(&msecs, sizeof(msecs));
        msecs = (labs(msecs) % (maxival - minival)) + minival;
@@ -567,7 +578,7 @@ static void forward_router_advertisement(uint8_t *data, size_t len)
                        size_t rewrite_cnt = iface->dns_cnt;
 
                        if (rewrite_cnt == 0) {
-                               if (odhcpd_get_preferred_interface_address(iface->ifindex, &addr) < 1)
+                               if (odhcpd_get_linklocal_interface_address(iface->ifindex, &addr))
                                        continue; // Unable to comply
 
                                rewrite = &addr;