Add support for (managed) prefixes of length 65-96

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

diff --git a/src/router.c b/src/router.c
index fffdc4c..907011a 100644 (file)
--- a/src/router.c
+++ b/src/router.c
@@ -130,23 +130,19 @@ static void sigusr1_refresh(_unused int signal)
                        uloop_timeout_set(&iface->timer_rs, 1000);
 }
 
-static int router_icmpv6_valid(struct sockaddr_in6 *source, uint8_t *data, size_t len)
+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;
-       size_t optlen = len - sizeof(*hdr);
+       struct icmpv6_opt *opt, *end = (struct icmpv6_opt*)&data[len];
 
        /* Hoplimit is already checked in odhcpd_receive_packets */
-       if (len < sizeof(*hdr))
-               return 0;
-
-       if (hdr->icmp6_code)
-               return 0;
+       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 0;
+                       return false;
 
                opt = (struct icmpv6_opt *)((struct nd_router_advert *)data + 1);
                break;
@@ -156,29 +152,17 @@ static int router_icmpv6_valid(struct sockaddr_in6 *source, uint8_t *data, size_
                break;
 
        default:
-               return 0;
+               return false;
        }
 
-       while (optlen > 0) {
-               size_t l = opt->len << 3;
-
-               if (optlen < sizeof(*opt))
-                       return 0;
+       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;
 
-               if (l > optlen || l == 0)
-                       return 0;
-
-               if (opt->type == ND_OPT_SOURCE_LINKADDR && IN6_IS_ADDR_UNSPECIFIED(&source->sin6_addr) &&
-                       hdr->icmp6_type == ND_ROUTER_SOLICIT) {
-                       return 0;
-               }
-
-               opt = (struct icmpv6_opt *)(((uint8_t *)opt) + l);
-
-               optlen -= l;
-       }
-
-       return 1;
+       // Check all options parsed successfully
+       return opt == end;
 }
 
 // Event handler for incoming ICMPv6 packets
@@ -186,7 +170,7 @@ 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;
 
@@ -289,6 +273,7 @@ static void send_router_advert(struct uloop_timeout *event)
        // If not currently shutting down
        struct odhcpd_ipaddr addrs[RELAYD_MAX_PREFIXES];
        ssize_t ipcnt = 0;
+       uint64_t maxpreferred = 0;
 
        // If not shutdown
        if (event->cb) {
@@ -311,7 +296,7 @@ static void send_router_advert(struct uloop_timeout *event)
 
        for (ssize_t i = 0; i < ipcnt; ++i) {
                struct odhcpd_ipaddr *addr = &addrs[i];
-               if (addr->prefix > 64 || addr->has_class)
+               if (addr->prefix > 96 || addr->has_class)
                        continue; // Address not suitable
 
                if (addr->preferred > MaxPreferredTime)
@@ -322,8 +307,9 @@ static void send_router_advert(struct uloop_timeout *event)
 
                struct nd_opt_prefix_info *p = NULL;
                for (size_t i = 0; i < cnt; ++i) {
-                       if (!memcmp(&adv.prefix[i].nd_opt_pi_prefix,
-                                       &addr->addr, 8))
+                       if (addr->prefix == adv.prefix[i].nd_opt_pi_prefix_len &&
+                                       !odhcpd_bmemcmp(&adv.prefix[i].nd_opt_pi_prefix,
+                                       &addr->addr, addr->prefix))
                                p = &adv.prefix[i];
                }
 
@@ -334,17 +320,21 @@ static void send_router_advert(struct uloop_timeout *event)
                        p = &adv.prefix[cnt++];
                }
 
-               if ((addr->addr.s6_addr[0] & 0xfe) != 0xfc && addr->preferred > 0)
+               if ((addr->addr.s6_addr[0] & 0xfe) != 0xfc && addr->preferred > 0) {
                        have_public = true;
 
-               memcpy(&p->nd_opt_pi_prefix, &addr->addr, 8);
+                       if (maxpreferred < 1000 * addr->preferred)
+                               maxpreferred = 1000 * addr->preferred;
+               }
+
+               odhcpd_bmemcpy(&p->nd_opt_pi_prefix, &addr->addr, addr->prefix);
                p->nd_opt_pi_type = ND_OPT_PREFIX_INFORMATION;
                p->nd_opt_pi_len = 4;
-               p->nd_opt_pi_prefix_len = 64;
+               p->nd_opt_pi_prefix_len = (addr->prefix < 64) ? 64 : addr->prefix;
                p->nd_opt_pi_flags_reserved = 0;
                if (!iface->ra_not_onlink)
                        p->nd_opt_pi_flags_reserved |= ND_OPT_PI_FLAG_ONLINK;
-               if (iface->managed < RELAYD_MANAGED_NO_AFLAG)
+               if (iface->managed < RELAYD_MANAGED_NO_AFLAG && addr->prefix <= 64)
                        p->nd_opt_pi_flags_reserved |= ND_OPT_PI_FLAG_AUTO;
                p->nd_opt_pi_valid_time = htonl(addr->valid);
                p->nd_opt_pi_preferred_time = htonl(addr->preferred);
@@ -361,11 +351,6 @@ 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;
@@ -472,12 +457,27 @@ 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) {
+               uint32_t maxinterval = MaxRtrAdvInterval * 1000;
+               uint32_t mininterval = MinRtrAdvInterval * 1000;
+
+               if (maxpreferred > 0 && maxinterval > maxpreferred / 2) {
+                       maxinterval = maxpreferred / 2;
+                       if (maxinterval < 4000)
+                               maxinterval = 4000;
+
+                       if (maxinterval >= 9000)
+                               mininterval = maxinterval / 3;
+                       else
+                               mininterval = (maxinterval * 3) / 4;
+               }
+
+               int msecs;
+               odhcpd_urandom(&msecs, sizeof(msecs));
+               msecs = (labs(msecs) % (maxinterval - mininterval)) + mininterval;
+               uloop_timeout_set(&iface->timer_rs, msecs);
+       }
 }