treewide: reflect managed mode is related to RA
[project/odhcpd.git] / src / router.c
index 7e666f1..cb2afc9 100644 (file)
@@ -20,6 +20,7 @@
 #include <stdlib.h>
 #include <unistd.h>
 #include <stdbool.h>
+#include <arpa/inet.h>
 #include <net/route.h>
 
 #include "router.h"
@@ -34,11 +35,11 @@ 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 = {.uloop = {.fd = -1}, .handle_dgram = handle_icmpv6, };
 
 static FILE *fp_route = NULL;
-#define RA_IOV_LEN 6
 
+#define TIME_LEFT(t1, now) ((t1) != UINT32_MAX ? (t1) - (now) : UINT32_MAX)
 
 int init_router(void)
 {
@@ -98,6 +99,9 @@ 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,
@@ -114,7 +118,7 @@ int setup_router_interface(struct interface *iface, bool enable)
                        forward_router_solicitation(iface);
                } else if (iface->ra == RELAYD_SERVER && !iface->master) {
                        iface->timer_rs.cb = trigger_router_advert;
-                       trigger_router_advert(&iface->timer_rs);
+                       uloop_timeout_set(&iface->timer_rs, 1000);
                }
 
                if (iface->ra == RELAYD_RELAY || (iface->ra == RELAYD_SERVER && !iface->master))
@@ -177,7 +181,9 @@ static bool parse_routes(struct odhcpd_ipaddr *n, ssize_t len)
 
        char line[512], ifname[16];
        bool found_default = false;
-       struct odhcpd_ipaddr p = {IN6ADDR_ANY_INIT, 0, 0, 0, 0};
+       struct odhcpd_ipaddr p = { .addr.in6 = IN6ADDR_ANY_INIT, .prefix = 0,
+                                       .dprefix = 0, .preferred = 0, .valid = 0};
+
        while (fgets(line, sizeof(line), fp_route)) {
                uint32_t rflags;
                if (sscanf(line, "00000000000000000000000000000000 00 "
@@ -186,15 +192,15 @@ static bool parse_routes(struct odhcpd_ipaddr *n, ssize_t len)
                        found_default = true;
                } else if (sscanf(line, "%8" SCNx32 "%8" SCNx32 "%*8" SCNx32 "%*8" SCNx32 " %hhx %*s "
                                "%*s 00000000000000000000000000000000 %*s %*s %*s %" SCNx32 " lo",
-                               &p.addr.s6_addr32[0], &p.addr.s6_addr32[1], &p.prefix, &rflags) &&
+                               &p.addr.in6.s6_addr32[0], &p.addr.in6.s6_addr32[1], &p.prefix, &rflags) &&
                                p.prefix > 0 && (rflags & RTF_NONEXTHOP) && (rflags & RTF_REJECT)) {
                        // Find source prefixes by scanning through unreachable-routes
-                       p.addr.s6_addr32[0] = htonl(p.addr.s6_addr32[0]);
-                       p.addr.s6_addr32[1] = htonl(p.addr.s6_addr32[1]);
+                       p.addr.in6.s6_addr32[0] = htonl(p.addr.in6.s6_addr32[0]);
+                       p.addr.in6.s6_addr32[1] = htonl(p.addr.in6.s6_addr32[1]);
 
                        for (ssize_t i = 0; i < len; ++i) {
                                if (n[i].prefix <= 64 && n[i].prefix >= p.prefix &&
-                                               !odhcpd_bmemcmp(&p.addr, &n[i].addr, p.prefix)) {
+                                               !odhcpd_bmemcmp(&p.addr.in6, &n[i].addr.in6, p.prefix)) {
                                        n[i].dprefix = p.prefix;
                                        break;
                                }
@@ -206,20 +212,80 @@ static bool parse_routes(struct odhcpd_ipaddr *n, ssize_t len)
        return found_default;
 }
 
+static int calc_adv_interval(struct interface *iface, uint32_t minvalid,
+               uint32_t *maxival)
+{
+       uint32_t minival = iface->ra_mininterval;
+       int msecs;
+
+       *maxival = iface->ra_maxinterval;
+
+       if (*maxival > minvalid/3)
+               *maxival = minvalid/3;
+
+       if (*maxival > MaxRtrAdvInterval)
+               *maxival = MaxRtrAdvInterval;
+       else if (*maxival < 4)
+               *maxival = 4;
+
+       if (minival < MinRtrAdvInterval)
+               minival = MinRtrAdvInterval;
+       else if (minival > (*maxival * 3)/4)
+               minival = (*maxival >= 9 ? *maxival/3 : *maxival);
+
+       odhcpd_urandom(&msecs, sizeof(msecs));
+       msecs = (labs(msecs) % ((*maxival != minival) ? (*maxival - minival)*1000 : 500)) +
+                       minival*1000;
+
+       return msecs;
+}
+
+static uint16_t calc_ra_lifetime(struct interface *iface, uint32_t maxival)
+{
+       uint16_t lifetime = 3*maxival;
+
+       if (iface->ra_lifetime >= 0) {
+               lifetime = iface->ra_lifetime;
+               if (lifetime < maxival)
+                       lifetime = maxival;
+               else if (lifetime > 9000)
+                       lifetime = 9000;
+       }
+
+       return lifetime;
+}
+
+enum {
+       IOV_RA_ADV=0,
+       IOV_RA_PFXS,
+       IOV_RA_ROUTES,
+       IOV_RA_DNS,
+       IOV_RA_DNS_ADDR,
+       IOV_RA_SEARCH,
+       IOV_RA_ADV_INTERVAL,
+       IOV_RA_TOTAL,
+};
+
 // Router Advert server mode
 static uint64_t send_router_advert(struct interface *iface, const struct in6_addr *from)
 {
-       int mtu = odhcpd_get_interface_config(iface->ifname, "mtu");
-       int hlim = odhcpd_get_interface_config(iface->ifname, "hop_limit");
+       time_t now = odhcpd_time();
+       int mtu = iface->ra_mtu;
+       int hlim = iface->ra_hoplimit;
+
+       if (mtu == 0)
+               mtu = odhcpd_get_interface_config(iface->ifname, "mtu");
 
        if (mtu < 1280)
                mtu = 1280;
 
+       if (hlim == 0)
+               hlim = odhcpd_get_interface_config(iface->ifname, "hop_limit");
+
        struct {
                struct nd_router_advert h;
                struct icmpv6_opt lladdr;
                struct nd_opt_mtu mtu;
-               struct nd_opt_prefix_info prefix[RELAYD_MAX_PREFIXES];
        } adv = {
                .h = {{.icmp6_type = ND_ROUTER_ADVERT, .icmp6_code = 0}, 0, 0},
                .lladdr = {ND_OPT_SOURCE_LINKADDR, 1, {0}},
@@ -232,78 +298,109 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
        if (iface->dhcpv6)
                adv.h.nd_ra_flags_reserved = ND_RA_FLAG_OTHER;
 
-       if (iface->managed >= RELAYD_MANAGED_MFLAG)
+       if (iface->ra_managed >= RA_MANAGED_MFLAG)
                adv.h.nd_ra_flags_reserved |= ND_RA_FLAG_MANAGED;
 
        if (iface->route_preference < 0)
                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;
+
+       adv.h.nd_ra_reachable = htonl(iface->ra_reachabletime);
+       adv.h.nd_ra_retransmit = htonl(iface->ra_retranstime);
+
        odhcpd_get_mac(iface, adv.lladdr.data);
 
        // If not currently shutting down
-       struct odhcpd_ipaddr addrs[RELAYD_MAX_PREFIXES];
+       struct odhcpd_ipaddr *addrs = NULL;
        ssize_t ipcnt = 0;
-       uint64_t minvalid = UINT64_MAX;
-       uint64_t maxvalid = 0;
+       uint32_t minvalid = UINT32_MAX;
+       bool default_route = false;
+       bool valid_prefix = false;
 
        // If not shutdown
        if (iface->timer_rs.cb) {
-               ipcnt = odhcpd_get_interface_addresses(iface->ifindex,
-                               addrs, ARRAY_SIZE(addrs));
+               size_t size = sizeof(*addrs) * iface->ia_addr_len;
+               addrs = alloca(size);
+               memcpy(addrs, iface->ia_addr, size);
+
+               ipcnt = iface->ia_addr_len;
 
                // Check default route
-               if (iface->default_router > 1)
-                       adv.h.nd_ra_router_lifetime = htons(iface->default_router);
-               if (parse_routes(addrs, ipcnt))
-                       adv.h.nd_ra_router_lifetime = htons(1);
+               if (iface->default_router) {
+                       default_route = true;
+
+                       if (iface->default_router > 1)
+                               valid_prefix = true;
+               } else if (parse_routes(addrs, ipcnt))
+                       default_route = true;
        }
 
-       // 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_interface_dns_addr(iface, &dns_pref);
+
+       // Construct Prefix Information options
+       size_t pfxs_cnt = 0;
+       struct nd_opt_prefix_info *pfxs = NULL;
+
        for (ssize_t i = 0; i < ipcnt; ++i) {
                struct odhcpd_ipaddr *addr = &addrs[i];
-               if (addr->prefix > 96)
-                       continue; // Address not suitable
+               uint32_t preferred = 0;
+               uint32_t valid = 0;
 
-               if (addr->preferred > MaxValidTime)
-                       addr->preferred = MaxValidTime;
+               if (addr->prefix > 96 || addr->valid <= (uint32_t)now) {
+                       char namebuf[INET6_ADDRSTRLEN];
 
-               if (addr->valid > MaxValidTime)
-                       addr->valid = MaxValidTime;
+                       inet_ntop(AF_INET6, &addr->addr.in6, namebuf, sizeof(namebuf));
+                       syslog(LOG_INFO, "Address %s (prefix %d, valid %u) not suitable as RA prefix on %s",
+                                       namebuf, addr->prefix, addr->valid, iface->ifname);
+                       continue;
+               }
 
                struct nd_opt_prefix_info *p = NULL;
-               for (size_t i = 0; i < cnt; ++i) {
-                       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];
+               for (size_t i = 0; i < pfxs_cnt; ++i) {
+                       if (addr->prefix == pfxs[i].nd_opt_pi_prefix_len &&
+                                       !odhcpd_bmemcmp(&pfxs[i].nd_opt_pi_prefix,
+                                       &addr->addr.in6, addr->prefix))
+                               p = &pfxs[i];
                }
 
                if (!p) {
-                       if (cnt >= ARRAY_SIZE(adv.prefix))
-                               break;
+                       struct nd_opt_prefix_info *tmp;
+
+                       tmp = realloc(pfxs, sizeof(*pfxs) * (pfxs_cnt + 1));
+                       if (!tmp) {
+                               syslog(LOG_ERR, "Realloc failed for RA prefix option on interface %s", iface->ifname);
+                               continue;
+                       }
+
+                       pfxs = tmp;
+                       p = &pfxs[pfxs_cnt++];
+                       memset(p, 0, sizeof(*p));
+               }
 
-                       p = &adv.prefix[cnt++];
+               if (addr->preferred > (uint32_t)now) {
+                       preferred = TIME_LEFT(addr->preferred, now);
+
+                       if (iface->ra_useleasetime &&
+                                       preferred > iface->dhcpv4_leasetime)
+                               preferred = iface->dhcpv4_leasetime;
                }
 
-               if (addr->preferred > 0 &&
-                               minvalid > 1000ULL * addr->valid)
-                       minvalid = 1000ULL * addr->valid;
+               valid = TIME_LEFT(addr->valid, now);
+               if (iface->ra_useleasetime && valid > iface->dhcpv4_leasetime)
+                       valid = iface->dhcpv4_leasetime;
 
-               if (maxvalid < 1000ULL * addr->valid)
-                       maxvalid = 1000ULL * addr->valid;
+               if (minvalid > valid)
+                       minvalid = valid;
 
-               if (((addr->addr.s6_addr[0] & 0xfe) != 0xfc || iface->default_router)
-                               && ntohs(adv.h.nd_ra_router_lifetime) < addr->valid)
-                       adv.h.nd_ra_router_lifetime = htons(addr->valid);
+               if (!IN6_IS_ADDR_ULA(&addr->addr.in6) || iface->default_router)
+                       valid_prefix = true;
 
-               odhcpd_bmemcpy(&p->nd_opt_pi_prefix, &addr->addr,
+               odhcpd_bmemcpy(&p->nd_opt_pi_prefix, &addr->addr.in6,
                                (iface->ra_advrouter) ? 128 : addr->prefix);
                p->nd_opt_pi_type = ND_OPT_PREFIX_INFORMATION;
                p->nd_opt_pi_len = 4;
@@ -311,30 +408,35 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
                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 && addr->prefix <= 64)
+               if (iface->ra_managed < RA_MANAGED_NO_AFLAG && addr->prefix <= 64)
                        p->nd_opt_pi_flags_reserved |= ND_OPT_PI_FLAG_AUTO;
                if (iface->ra_advrouter)
                        p->nd_opt_pi_flags_reserved |= ND_OPT_PI_FLAG_RADDR;
-               p->nd_opt_pi_valid_time = htonl(addr->valid);
-               p->nd_opt_pi_preferred_time = htonl(addr->preferred);
-
-               if (addr->preferred > dns_time) {
-                       dns_time = addr->preferred;
-                       dns_pref = addr->addr;
-               }
+               p->nd_opt_pi_preferred_time = htonl(preferred);
+               p->nd_opt_pi_valid_time = htonl(valid);
        }
 
-       if (!iface->default_router && ntohs(adv.h.nd_ra_router_lifetime) == 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);
+       // Calculate periodic transmit
+       uint32_t maxival;
+       int msecs = calc_adv_interval(iface, minvalid, &maxival);
+
+       if (default_route) {
+               if (!valid_prefix) {
+                       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;
+               } else
+                       adv.h.nd_ra_router_lifetime = htons(calc_ra_lifetime(iface, maxival));
+
+       } else
                adv.h.nd_ra_router_lifetime = 0;
-       }
+
+       syslog(LOG_INFO, "Using a RA lifetime of %d seconds on %s", ntohs(adv.h.nd_ra_router_lifetime), iface->ifname);
 
        // DNS Recursive DNS
        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))
@@ -346,9 +448,7 @@ 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};
 
        // DNS Search options
        uint8_t search_buf[256], *search_domain = iface->search;
@@ -391,20 +491,29 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
                uint8_t flags;
                uint32_t lifetime;
                uint32_t addr[4];
-       } routes[RELAYD_MAX_PREFIXES];
+       } *tmp, *routes = NULL;
 
        for (ssize_t i = 0; i < ipcnt; ++i) {
                struct odhcpd_ipaddr *addr = &addrs[i];
-               if (addr->dprefix > 64 || addr->dprefix == 0 ||
+               if (addr->dprefix > 64 || addr->dprefix == 0 || addr->valid <= (uint32_t)now ||
                                (addr->dprefix == 64 && addr->prefix == 64)) {
                        continue; // Address not suitable
                } else if (addr->dprefix > 32) {
-                       addr->addr.s6_addr32[1] &= htonl(~((1U << (64 - addr->dprefix)) - 1));
+                       addr->addr.in6.s6_addr32[1] &= htonl(~((1U << (64 - addr->dprefix)) - 1));
                } else if (addr->dprefix <= 32) {
-                       addr->addr.s6_addr32[0] &= htonl(~((1U << (32 - addr->dprefix)) - 1));
-                       addr->addr.s6_addr32[1] = 0;
+                       addr->addr.in6.s6_addr32[0] &= htonl(~((1U << (32 - addr->dprefix)) - 1));
+                       addr->addr.in6.s6_addr32[1] = 0;
                }
 
+               tmp = realloc(routes, sizeof(*routes) * (routes_cnt + 1));
+               if (!tmp) {
+                       syslog(LOG_ERR, "Realloc failed for RA route option on interface %s", iface->ifname);
+                       continue;
+               }
+
+               routes = tmp;
+
+               memset(&routes[routes_cnt], 0, sizeof(*routes));
                routes[routes_cnt].type = ND_OPT_ROUTE_INFO;
                routes[routes_cnt].len = sizeof(*routes) / 8;
                routes[routes_cnt].prefix = addr->dprefix;
@@ -413,53 +522,32 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
                        routes[routes_cnt].flags |= ND_RA_PREF_LOW;
                else if (iface->route_preference > 0)
                        routes[routes_cnt].flags |= ND_RA_PREF_HIGH;
-               routes[routes_cnt].lifetime = htonl(addr->valid);
-               routes[routes_cnt].addr[0] = addr->addr.s6_addr32[0];
-               routes[routes_cnt].addr[1] = addr->addr.s6_addr32[1];
+               routes[routes_cnt].lifetime = htonl(TIME_LEFT(addr->valid, now));
+               routes[routes_cnt].addr[0] = addr->addr.in6.s6_addr32[0];
+               routes[routes_cnt].addr[1] = addr->addr.in6.s6_addr32[1];
                routes[routes_cnt].addr[2] = 0;
                routes[routes_cnt].addr[3] = 0;
 
                ++routes_cnt;
        }
 
-       // Calculate periodic transmit
-       int msecs = 0;
-       uint32_t maxival = iface->ra_maxinterval * 1000;
-       uint32_t minival;
-
-       if (maxival < 4000 || maxival > MaxRtrAdvInterval * 1000)
-               maxival = MaxRtrAdvInterval * 1000;
-
-       if (maxival > minvalid / 3) {
-               maxival = minvalid / 3;
-
-               if (maxival < 4000)
-                       maxival = 4000;
-       }
-
-       minival = (maxival * 3) / 4;
-
-       search->lifetime = htonl(maxvalid / 1000);
-
-       if (!dns.lifetime)
-               dns.lifetime = search->lifetime;
-
-       odhcpd_urandom(&msecs, sizeof(msecs));
-       msecs = (labs(msecs) % (maxival - minival)) + minival;
+       search->lifetime = htonl(maxival*10);
+       dns.lifetime = search->lifetime;
 
        struct icmpv6_opt adv_interval = {
                .type = ND_OPT_RTR_ADV_INTERVAL,
                .len = 1,
-               .data = {0, 0, maxival >> 24, maxival >> 16, maxival >> 8, maxival}
+               .data = {0, 0, (maxival*1000) >> 24, (maxival*1000) >> 16, (maxival*1000) >> 8, maxival*1000}
        };
 
-       struct iovec iov[RA_IOV_LEN] = {
-                       {&adv, (uint8_t*)&adv.prefix[cnt] - (uint8_t*)&adv},
-                       {&routes, routes_cnt * sizeof(*routes)},
-                       {&dns, (dns_cnt) ? sizeof(dns) : 0},
-                       {dns_addr, dns_cnt * sizeof(*dns_addr)},
-                       {search, search->len * 8},
-                       {&adv_interval, adv_interval.len * 8}};
+       struct iovec iov[IOV_RA_TOTAL] = {
+                       [IOV_RA_ADV] = {&adv, sizeof(adv)},
+                       [IOV_RA_PFXS] = {pfxs, pfxs_cnt * sizeof(*pfxs)},
+                       [IOV_RA_ROUTES] = {routes, routes_cnt * sizeof(*routes)},
+                       [IOV_RA_DNS] = {&dns, (dns_cnt) ? sizeof(dns) : 0},
+                       [IOV_RA_DNS_ADDR] = {dns_addr, dns_cnt * sizeof(*dns_addr)},
+                       [IOV_RA_SEARCH] = {search, search->len * 8},
+                       [IOV_RA_ADV_INTERVAL] = {&adv_interval, adv_interval.len * 8}};
        struct sockaddr_in6 dest = {AF_INET6, 0, 0, ALL_IPV6_NODES, 0};
 
        if (from && !IN6_IS_ADDR_UNSPECIFIED(from))
@@ -468,6 +556,9 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
        odhcpd_send(router_event.uloop.fd,
                        &dest, iov, ARRAY_SIZE(iov), iface);
 
+       free(pfxs);
+       free(routes);
+
        return msecs;
 }
 
@@ -569,7 +660,7 @@ 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_interface_dns_addr(iface, &addr))
                                        continue; // Unable to comply
 
                                rewrite = &addr;