Don't rearm rs timer if callback is not set
[project/odhcpd.git] / src / router.c
index 0b01a77..dfbcf60 100644 (file)
@@ -130,12 +130,50 @@ static void sigusr1_refresh(_unused int signal)
                        uloop_timeout_set(&iface->timer_rs, 1000);
 }
 
+static bool router_icmpv6_valid(struct sockaddr_in6 *source, uint8_t *data, size_t len)
+{
+       struct icmp6_hdr *hdr = (struct icmp6_hdr *)data;
+       struct icmpv6_opt *opt, *end = (struct icmpv6_opt*)&data[len];
+
+       /* Hoplimit is already checked in odhcpd_receive_packets */
+       if (len < sizeof(*hdr) || hdr->icmp6_code)
+               return false;
+
+       switch (hdr->icmp6_type) {
+       case ND_ROUTER_ADVERT:
+               if (!IN6_IS_ADDR_LINKLOCAL(&source->sin6_addr))
+                       return false;
+
+               opt = (struct icmpv6_opt *)((struct nd_router_advert *)data + 1);
+               break;
+
+       case ND_ROUTER_SOLICIT:
+               opt = (struct icmpv6_opt *)((struct nd_router_solicit *)data + 1);
+               break;
+
+       default:
+               return false;
+       }
+
+       icmpv6_for_each_option(opt, opt, end)
+               if (opt->type == ND_OPT_SOURCE_LINKADDR &&
+                               IN6_IS_ADDR_UNSPECIFIED(&source->sin6_addr) &&
+                               hdr->icmp6_type == ND_ROUTER_SOLICIT)
+                       return false;
+
+       // Check all options parsed successfully
+       return opt == end;
+}
 
 // Event handler for incoming ICMPv6 packets
-static void handle_icmpv6(_unused void *addr, void *data, size_t len,
+static void handle_icmpv6(void *addr, void *data, size_t len,
                struct interface *iface)
 {
        struct icmp6_hdr *hdr = data;
+
+       if (!router_icmpv6_valid(addr, data, len))
+               return;
+
        if ((iface->ra == RELAYD_SERVER && !iface->master)) { // Server mode
                if (hdr->icmp6_type == ND_ROUTER_SOLICIT)
                        send_router_advert(&iface->timer_rs);
@@ -211,7 +249,7 @@ static void send_router_advert(struct uloop_timeout *event)
 
        struct {
                struct nd_router_advert h;
-               struct nd_opt_slla lladdr;
+               struct icmpv6_opt lladdr;
                struct nd_opt_mtu mtu;
                struct nd_opt_prefix_info prefix[RELAYD_MAX_PREFIXES];
        } adv = {
@@ -219,7 +257,10 @@ static void send_router_advert(struct uloop_timeout *event)
                .lladdr = {ND_OPT_SOURCE_LINKADDR, 1, {0}},
                .mtu = {ND_OPT_MTU, 1, 0, htonl(mtu)},
        };
-       adv.h.nd_ra_flags_reserved = ND_RA_FLAG_OTHER;
+
+       if (iface->dhcpv6)
+               adv.h.nd_ra_flags_reserved = ND_RA_FLAG_OTHER;
+
        if (iface->managed >= RELAYD_MANAGED_MFLAG)
                adv.h.nd_ra_flags_reserved |= ND_RA_FLAG_MANAGED;
 
@@ -227,7 +268,7 @@ static void send_router_advert(struct uloop_timeout *event)
                adv.h.nd_ra_flags_reserved |= ND_RA_PREF_LOW;
        else if (iface->route_preference > 0)
                adv.h.nd_ra_flags_reserved |= ND_RA_PREF_HIGH;
-       odhcpd_get_mac(iface, adv.lladdr.addr);
+       odhcpd_get_mac(iface, adv.lladdr.data);
 
        // If not currently shutting down
        struct odhcpd_ipaddr addrs[RELAYD_MAX_PREFIXES];
@@ -304,11 +345,6 @@ static void send_router_advert(struct uloop_timeout *event)
                adv.h.nd_ra_router_lifetime = 0;
        }
 
-       if (have_public && iface->deprecate_ula_if_public_avail)
-               for (size_t i = 0; i < cnt; ++i)
-                       if ((adv.prefix[i].nd_opt_pi_prefix.s6_addr[0] & 0xfe) == 0xfc)
-                               adv.prefix[i].nd_opt_pi_preferred_time = 0;
-
        // DNS Recursive DNS
        if (iface->dns_cnt > 0) {
                dns_addr = iface->dns;
@@ -319,7 +355,14 @@ static void send_router_advert(struct uloop_timeout *event)
        if (!dns_addr)
                dns_cnt = 0;
 
-       struct nd_opt_recursive_dns dns = {ND_OPT_RECURSIVE_DNS, (1 + (2 * dns_cnt)), 0, 0, htonl(dns_time)};
+       struct {
+               uint8_t type;
+               uint8_t len;
+               uint8_t pad;
+               uint8_t pad2;
+               uint32_t lifetime;
+       } dns = {ND_OPT_RECURSIVE_DNS, (1 + (2 * dns_cnt)), 0, 0, htonl(dns_time)};
+
 
 
        // DNS Search options
@@ -408,12 +451,14 @@ static void send_router_advert(struct uloop_timeout *event)
        odhcpd_send(router_event.uloop.fd,
                        &all_nodes, iov, ARRAY_SIZE(iov), iface);
 
-       // Rearm timer
-       int msecs;
-       odhcpd_urandom(&msecs, sizeof(msecs));
-       msecs = (labs(msecs) % (1000 * (MaxRtrAdvInterval
-                       - MinRtrAdvInterval))) + (MinRtrAdvInterval * 1000);
-       uloop_timeout_set(&iface->timer_rs, msecs);
+       // Rearm timer if not shut down
+       if (event->cb) {
+               int msecs;
+               odhcpd_urandom(&msecs, sizeof(msecs));
+               msecs = (labs(msecs) % (1000 * (MaxRtrAdvInterval
+                               - MinRtrAdvInterval))) + (MinRtrAdvInterval * 1000);
+               uloop_timeout_set(&iface->timer_rs, msecs);
+       }
 }
 
 
@@ -448,12 +493,11 @@ static void forward_router_advertisement(uint8_t *data, size_t len)
        icmpv6_for_each_option(opt, &adv[1], end) {
                if (opt->type == ND_OPT_SOURCE_LINKADDR) {
                        // Store address of source MAC-address
-                       mac_ptr = ((struct nd_opt_slla *)opt)->addr;
+                       mac_ptr = opt->data;
                } else if (opt->type == ND_OPT_RECURSIVE_DNS && opt->len > 1) {
-                       struct nd_opt_recursive_dns *dns = (struct nd_opt_recursive_dns *)opt;
                        // Check if we have to rewrite DNS
-                       dns_ptr = (struct in6_addr *)&dns[1];
-                       dns_count = (dns->len - 1) / 2;
+                       dns_ptr = (struct in6_addr*)&opt->data[6];
+                       dns_count = (opt->len - 1) / 2;
                }
        }