ra/dhcpv6: unify address change handling
authorSteven Barth <steven@midlink.org>
Mon, 27 Jul 2015 21:21:57 +0000 (23:21 +0200)
committerSteven Barth <steven@midlink.org>
Mon, 27 Jul 2015 21:21:57 +0000 (23:21 +0200)
src/dhcpv6-ia.c
src/dhcpv6.h
src/ndp.c
src/router.c

index 6ea49b0a97cf8b6432dfd9ebef63e0e1471f9658..c5f8783ca9fd543be2d5a2c1ca179e996d158bf4 100644 (file)
@@ -34,7 +34,6 @@
 #include <sys/timerfd.h>
 
 
-static void update(struct interface *iface);
 static void reconf_timer(struct uloop_timeout *event);
 static struct uloop_timeout reconf_event = {.cb = reconf_timer};
 static uint32_t serial = 0;
@@ -89,8 +88,6 @@ int setup_dhcpv6_ia_interface(struct interface *iface, bool enable)
                        list_add(&border->head, &iface->ia_assignments);
                }
 
-               update(iface);
-
                // Parse static entries
                struct lease *lease;
                list_for_each_entry(lease, &leases, head) {
@@ -556,106 +553,73 @@ static bool assign_na(struct interface *iface, struct dhcpv6_assignment *assign)
        return false;
 }
 
-
-static int prefixcmp(const void *va, const void *vb)
+void dhcpv6_ia_preupdate(struct interface *iface)
 {
-       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;
-}
+       if (iface->dhcpv6 != RELAYD_SERVER)
+               return;
 
+       struct dhcpv6_assignment *c, *border = list_last_entry(
+                       &iface->ia_assignments, struct dhcpv6_assignment, head);
+       list_for_each_entry(c, &iface->ia_assignments, head)
+               if (c != border && !iface->managed)
+                       apply_lease(iface, c, false);
+}
 
-static void update(struct interface *iface)
+void dhcpv6_ia_postupdate(struct interface *iface, time_t now)
 {
-       struct odhcpd_ipaddr addr[8];
-       memset(addr, 0, sizeof(addr));
-       int len = odhcpd_get_interface_addresses(iface->ifindex, addr, 8);
-
-       if (len < 0)
+       if (iface->dhcpv6 != RELAYD_SERVER)
                return;
 
-       qsort(addr, len, sizeof(*addr), prefixcmp);
-
-       time_t now = odhcpd_time();
        int minprefix = -1;
-
-       for (int i = 0; i < len; ++i) {
-               if (addr[i].preferred > 0 && addr[i].prefix < 64 &&
-                               addr[i].prefix > minprefix)
-                       minprefix = addr[i].prefix;
-
-               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;
+       for (size_t i = 0; i < iface->ia_addr_len; ++i) {
+               if (iface->ia_addr[i].preferred > now &&
+                               iface->ia_addr[i].prefix < 64 &&
+                               iface->ia_addr[i].prefix > minprefix)
+                       minprefix = iface->ia_addr[i].prefix;
        }
 
-       struct dhcpv6_assignment *border = list_last_entry(&iface->ia_assignments, struct dhcpv6_assignment, head);
+       struct dhcpv6_assignment *border = list_last_entry(
+                       &iface->ia_assignments, struct dhcpv6_assignment, head);
        if (minprefix > 32 && minprefix <= 64)
                border->assigned = 1U << (64 - minprefix);
        else
                border->assigned = 0;
 
-       bool change = len != (int)iface->ia_addr_len;
-       for (int i = 0; !change && i < len; ++i)
-               if (addr[i].addr.s6_addr32[0] != iface->ia_addr[i].addr.s6_addr32[0] ||
-                               addr[i].addr.s6_addr32[1] != iface->ia_addr[i].addr.s6_addr32[1] ||
-                               (addr[i].preferred > 0) != (iface->ia_addr[i].preferred > 0) ||
-                               (addr[i].valid > (uint32_t)now + 7200) !=
-                                               (iface->ia_addr[i].valid > (uint32_t)now + 7200))
-                       change = true;
-
-       if (change) {
-               struct dhcpv6_assignment *c;
-               list_for_each_entry(c, &iface->ia_assignments, head)
-                       if (c != border && !iface->managed)
-                               apply_lease(iface, c, false);
-       }
-
-       memcpy(iface->ia_addr, addr, len * sizeof(*addr));
-       iface->ia_addr_len = len;
+       struct list_head reassign = LIST_HEAD_INIT(reassign);
+       struct dhcpv6_assignment *c, *d;
+       list_for_each_entry_safe(c, d, &iface->ia_assignments, head) {
+               if (c->clid_len == 0 || c->valid_until < now || c->managed_size)
+                       continue;
 
-       if (change) { // Addresses / prefixes have changed
-               struct list_head reassign = LIST_HEAD_INIT(reassign);
-               struct dhcpv6_assignment *c, *d;
-               list_for_each_entry_safe(c, d, &iface->ia_assignments, head) {
-                       if (c->clid_len == 0 || c->valid_until < now || c->managed_size)
-                               continue;
+               if (c->length < 128 && c->assigned >= border->assigned && c != border)
+                       list_move(&c->head, &reassign);
+               else if (c != border)
+                       apply_lease(iface, c, true);
 
-                       if (c->length < 128 && c->assigned >= border->assigned && c != border)
-                               list_move(&c->head, &reassign);
-                       else if (c != border)
-                               apply_lease(iface, c, true);
-
-                       if (c->accept_reconf && c->reconf_cnt == 0) {
-                               c->reconf_cnt = 1;
-                               c->reconf_sent = now;
-                               send_reconf(iface, c);
-
-                               // Leave all other assignments of that client alone
-                               struct dhcpv6_assignment *a;
-                               list_for_each_entry(a, &iface->ia_assignments, head)
-                                       if (a != c && a->clid_len == c->clid_len &&
-                                                       !memcmp(a->clid_data, c->clid_data, a->clid_len))
-                                               c->reconf_cnt = INT_MAX;
-                       }
+               if (c->accept_reconf && c->reconf_cnt == 0) {
+                       c->reconf_cnt = 1;
+                       c->reconf_sent = now;
+                       send_reconf(iface, c);
+
+                       // Leave all other assignments of that client alone
+                       struct dhcpv6_assignment *a;
+                       list_for_each_entry(a, &iface->ia_assignments, head)
+                               if (a != c && a->clid_len == c->clid_len &&
+                                               !memcmp(a->clid_data, c->clid_data, a->clid_len))
+                                       c->reconf_cnt = INT_MAX;
                }
+       }
 
-               while (!list_empty(&reassign)) {
-                       c = list_first_entry(&reassign, struct dhcpv6_assignment, head);
-                       list_del(&c->head);
-                       if (!assign_pd(iface, c)) {
-                               c->assigned = 0;
-                               list_add(&c->head, &iface->ia_assignments);
-                       }
+       while (!list_empty(&reassign)) {
+               c = list_first_entry(&reassign, struct dhcpv6_assignment, head);
+               list_del(&c->head);
+               if (!assign_pd(iface, c)) {
+                       c->assigned = 0;
+                       list_add(&c->head, &iface->ia_assignments);
                }
-
-               dhcpv6_write_statefile();
        }
+
+       dhcpv6_write_statefile();
 }
 
 
@@ -1009,8 +973,6 @@ ssize_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
        if (!clid_data || !clid_len || clid_len > 130)
                goto out;
 
-       update(iface);
-
        struct dhcpv6_assignment *first = NULL;
        dhcpv6_for_each_option(start, end, otype, olen, odata) {
                bool is_pd = (otype == DHCPV6_OPT_IA_PD);
index 09aa6f13eb77602fb677ee227419d659be372ec5..d9f42c816b88b23a346bc8f08d282b5c0df90226 100644 (file)
@@ -14,6 +14,7 @@
 #pragma once
 
 #include <libubox/ustream.h>
+#include "odhcpd.h"
 
 #define ALL_DHCPV6_RELAYS {{{0xff, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,\
                0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x02}}}
@@ -181,3 +182,5 @@ ssize_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
 int dhcpv6_ia_init(void);
 int setup_dhcpv6_ia_interface(struct interface *iface, bool enable);
 void dhcpv6_write_statefile(void);
+void dhcpv6_ia_preupdate(struct interface *iface);
+void dhcpv6_ia_postupdate(struct interface *iface, time_t now);
index 2aa55be6e94bc54c00397975f51c05c68b13a9a5..7f63f96099c1b34c8cc22459074e4156ad4f3d8b 100644 (file)
--- a/src/ndp.c
+++ b/src/ndp.c
@@ -29,6 +29,7 @@
 #include <linux/rtnetlink.h>
 #include <linux/filter.h>
 #include "router.h"
+#include "dhcpv6.h"
 #include "ndp.h"
 
 
@@ -272,6 +273,58 @@ static void setup_route(struct in6_addr *addr, struct interface *iface, bool add
                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;
+
+       if (change)
+               dhcpv6_ia_postupdate(iface, now);
+
+       if (change)
+               raise(SIGUSR1);
+}
+
 
 // Handler for neighbor cache entries from the kernel. This is our source
 // to learn and unlearn hosts on interfaces.
@@ -412,8 +465,7 @@ static void handle_rtnetlink(_unused void *addr, void *data, size_t len,
                }
 
                if (is_addr) {
-                       if (iface->ra == RELAYD_SERVER)
-                               raise(SIGUSR1); // Inform about a change in addresses
+                       check_updates(iface);
 
                        if (iface->dhcpv6 == RELAYD_SERVER)
                                iface->ia_reconf = true;
index 7e666f1b88d7aaa72edb97b30deff4439f05b025..36f6ae79bf6813438760fe5e1305aae592f2b211 100644 (file)
@@ -114,7 +114,7 @@ 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))
@@ -209,6 +209,7 @@ static bool parse_routes(struct odhcpd_ipaddr *n, ssize_t len)
 // Router Advert server mode
 static uint64_t send_router_advert(struct interface *iface, const struct in6_addr *from)
 {
+       time_t now = odhcpd_time();
        int mtu = odhcpd_get_interface_config(iface->ifname, "mtu");
        int hlim = odhcpd_get_interface_config(iface->ifname, "hop_limit");
 
@@ -219,7 +220,7 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
                struct nd_router_advert h;
                struct icmpv6_opt lladdr;
                struct nd_opt_mtu mtu;
-               struct nd_opt_prefix_info prefix[RELAYD_MAX_PREFIXES];
+               struct nd_opt_prefix_info prefix[sizeof(iface->ia_addr) / sizeof(*iface->ia_addr)];
        } adv = {
                .h = {{.icmp6_type = ND_ROUTER_ADVERT, .icmp6_code = 0}, 0, 0},
                .lladdr = {ND_OPT_SOURCE_LINKADDR, 1, {0}},
@@ -242,21 +243,21 @@ 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[RELAYD_MAX_PREFIXES];
+       struct odhcpd_ipaddr *addrs = NULL;
        ssize_t ipcnt = 0;
-       uint64_t minvalid = UINT64_MAX;
-       uint64_t maxvalid = 0;
+       int64_t minvalid = INT64_MAX;
+       int64_t maxvalid = 0;
 
        // If not shutdown
        if (iface->timer_rs.cb) {
-               ipcnt = odhcpd_get_interface_addresses(iface->ifindex,
-                               addrs, ARRAY_SIZE(addrs));
+               addrs = iface->ia_addr;
+               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 > 1)
+                       adv.h.nd_ra_router_lifetime = htons(iface->default_router);
        }
 
        // Construct Prefix Information options
@@ -268,15 +269,9 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
 
        for (ssize_t i = 0; i < ipcnt; ++i) {
                struct odhcpd_ipaddr *addr = &addrs[i];
-               if (addr->prefix > 96)
+               if (addr->prefix > 96 || addr->valid <= now)
                        continue; // Address not suitable
 
-               if (addr->preferred > MaxValidTime)
-                       addr->preferred = MaxValidTime;
-
-               if (addr->valid > MaxValidTime)
-                       addr->valid = MaxValidTime;
-
                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 &&
@@ -292,16 +287,16 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
                        p = &adv.prefix[cnt++];
                }
 
-               if (addr->preferred > 0 &&
-                               minvalid > 1000ULL * addr->valid)
-                       minvalid = 1000ULL * addr->valid;
+               if (addr->preferred > now &&
+                               minvalid > 1000LL * (addr->valid - now))
+                       minvalid = 1000LL * (addr->valid - now);
 
-               if (maxvalid < 1000ULL * addr->valid)
-                       maxvalid = 1000ULL * addr->valid;
+               if (maxvalid < 1000LL * (addr->valid - now))
+                       maxvalid = 1000LL * (addr->valid - now);
 
                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);
+                               && ntohs(adv.h.nd_ra_router_lifetime) < addr->valid - now)
+                       adv.h.nd_ra_router_lifetime = htons(addr->valid - now);
 
                odhcpd_bmemcpy(&p->nd_opt_pi_prefix, &addr->addr,
                                (iface->ra_advrouter) ? 128 : addr->prefix);
@@ -315,11 +310,13 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
                        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);
+               p->nd_opt_pi_valid_time = htonl(addr->valid - now);
+               if (addr->preferred > now)
+                       p->nd_opt_pi_preferred_time = htonl(addr->preferred - now);
+
 
-               if (addr->preferred > dns_time) {
-                       dns_time = addr->preferred;
+               if (addr->preferred - now > dns_time) {
+                       dns_time = addr->preferred - now;
                        dns_pref = addr->addr;
                }
        }
@@ -395,7 +392,7 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
 
        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 <= now ||
                                (addr->dprefix == 64 && addr->prefix == 64)) {
                        continue; // Address not suitable
                } else if (addr->dprefix > 32) {
@@ -413,7 +410,7 @@ 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].lifetime = htonl(addr->valid - now);
                routes[routes_cnt].addr[0] = addr->addr.s6_addr32[0];
                routes[routes_cnt].addr[1] = addr->addr.s6_addr32[1];
                routes[routes_cnt].addr[2] = 0;