]> git.decadent.org.uk Git - odhcp6c.git/blobdiff - src/dhcpv6.c
Avoid updating too often if ISP spams RAs
[odhcp6c.git] / src / dhcpv6.c
index e93d894935122af9cfbbfc3661eed2bff581015c..f905a7836d2ba601d5b98c5a10d72e77bd53da34 100644 (file)
@@ -1,5 +1,5 @@
 /**
- * Copyright (C) 2012 Steven Barth <steven@midlink.org>
+ * Copyright (C) 2012-2013 Steven Barth <steven@midlink.org>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License v2 as published by
@@ -15,6 +15,7 @@
 #include <time.h>
 #include <fcntl.h>
 #include <errno.h>
+#include <stdlib.h>
 #include <signal.h>
 #include <limits.h>
 #include <resolv.h>
@@ -31,6 +32,7 @@
 #include <net/ethernet.h>
 
 #include "odhcp6c.h"
+#include "md5.h"
 
 
 #define ALL_DHCPV6_RELAYS {{{0xff, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,\
 static bool dhcpv6_response_is_valid(const void *buf, ssize_t len,
                const uint8_t transaction[3], enum dhcpv6_msg type);
 
-static time_t dhcpv6_parse_ia(void *opt, void *end);
+static uint32_t dhcpv6_parse_ia(void *opt, void *end);
 
 static reply_handler dhcpv6_handle_reply;
 static reply_handler dhcpv6_handle_advert;
 static reply_handler dhcpv6_handle_rebind_reply;
 static reply_handler dhcpv6_handle_reconfigure;
-static int dhcpv6_commit_advert(uint32_t elapsed);
+static int dhcpv6_commit_advert(void);
 
 
 
@@ -60,7 +62,7 @@ static struct dhcpv6_retx dhcpv6_retx[_DHCPV6_MSG_MAX] = {
                        dhcpv6_handle_reconfigure, NULL},
        [DHCPV6_MSG_SOLICIT] = {true, 1, 120, "SOLICIT",
                        dhcpv6_handle_advert, dhcpv6_commit_advert},
-       [DHCPV6_MSG_REQUEST] = {true, 30, 10, "REQUEST",
+       [DHCPV6_MSG_REQUEST] = {true, 1, 30, "REQUEST",
                        dhcpv6_handle_reply, NULL},
        [DHCPV6_MSG_RENEW] = {false, 10, 600, "RENEW",
                        dhcpv6_handle_reply, NULL},
@@ -75,23 +77,23 @@ static struct dhcpv6_retx dhcpv6_retx[_DHCPV6_MSG_MAX] = {
 
 // Sockets
 static int sock = -1;
-static int urandom_fd = -1;
 static int ifindex = -1;
-static time_t t1 = 0, t2 = 0, t3 = 0;
+static int64_t t1 = 0, t2 = 0, t3 = 0;
 
 // IA states
 static int request_prefix = -1;
-static enum odhcp6c_ia_mode na_mode = IA_MODE_NONE;
+static enum odhcp6c_ia_mode na_mode = IA_MODE_NONE, pd_mode = IA_MODE_NONE;
 static bool accept_reconfig = false;
 
+// Reconfigure key
+static uint8_t reconf_key[16];
 
 
-int init_dhcpv6(const char *ifname, int request_pd)
+
+int init_dhcpv6(const char *ifname, int request_pd, int sol_timeout)
 {
        request_prefix = request_pd;
-       urandom_fd = open("/dev/urandom", O_CLOEXEC | O_RDONLY);
-       if (urandom_fd < 0)
-               return -1;
+       dhcpv6_retx[DHCPV6_MSG_SOLICIT].max_timeo = sol_timeout;
 
        sock = socket(AF_INET6, SOCK_DGRAM | SOCK_CLOEXEC, IPPROTO_UDP);
 
@@ -110,12 +112,44 @@ int init_dhcpv6(const char *ifname, int request_pd)
                uint8_t duid[14] = {0, DHCPV6_OPT_CLIENTID, 0, 10, 0,
                                DHCPV6_DUID_LLADDR, 0, 1};
                memcpy(&duid[8], ifr.ifr_hwaddr.sa_data, ETHER_ADDR_LEN);
+
+               uint8_t zero[ETHER_ADDR_LEN] = {0, 0, 0, 0, 0, 0};
+               struct ifreq ifs[100], *ifp, *ifend;
+               struct ifconf ifc;
+               ifc.ifc_req = ifs;
+               ifc.ifc_len = sizeof(ifs);
+
+               if (!memcmp(&duid[8], zero, ETHER_ADDR_LEN) &&
+                               ioctl(sock, SIOCGIFCONF, &ifc) >= 0) {
+                       // If our interface doesn't have an address...
+                       ifend = ifs + (ifc.ifc_len / sizeof(struct ifreq));
+                       for (ifp = ifc.ifc_req; ifp < ifend &&
+                                       !memcmp(&duid[8], zero, 6); ifp++) {
+                               memcpy(ifr.ifr_name, ifp->ifr_name,
+                                               sizeof(ifr.ifr_name));
+                               ioctl(sock, SIOCGIFHWADDR, &ifr);
+                               memcpy(&duid[8], ifr.ifr_hwaddr.sa_data,
+                                               ETHER_ADDR_LEN);
+                       }
+               }
+
                odhcp6c_add_state(STATE_CLIENT_ID, duid, sizeof(duid));
        }
 
        // Create ORO
-       uint16_t oro[] = {htons(DHCPV6_OPT_DNS_SERVERS),
-                       htons(DHCPV6_OPT_DNS_DOMAIN)};
+       uint16_t oro[] = {
+                       htons(DHCPV6_OPT_SIP_SERVER_D),
+                       htons(DHCPV6_OPT_SIP_SERVER_A),
+                       htons(DHCPV6_OPT_DNS_SERVERS),
+                       htons(DHCPV6_OPT_DNS_DOMAIN),
+                       htons(DHCPV6_OPT_NTP_SERVER),
+                       htons(DHCPV6_OPT_SIP_SERVER_A),
+                       htons(DHCPV6_OPT_AFTR_NAME),
+                       htons(DHCPV6_OPT_PD_EXCLUDE),
+#ifdef EXT_PREFIX_CLASS
+                       htons(DHCPV6_OPT_PREFIX_CLASS),
+#endif
+       };
        odhcp6c_add_state(STATE_ORO, oro, sizeof(oro));
 
 
@@ -134,21 +168,10 @@ int init_dhcpv6(const char *ifname, int request_pd)
 }
 
 
-void dhcpv6_set_ia_na_mode(enum odhcp6c_ia_mode mode)
+void dhcpv6_set_ia_mode(enum odhcp6c_ia_mode na, enum odhcp6c_ia_mode pd)
 {
-       na_mode = mode;
-}
-
-
-void dhcpv6_remove_addrs(void)
-{
-       size_t ia_na_len;
-       uint8_t *odata, *ia_na = odhcp6c_get_state(STATE_IA_NA, &ia_na_len);
-       uint16_t otype, olen;
-       dhcpv6_for_each_option(ia_na, ia_na + ia_na_len, otype, olen, odata) {
-               struct dhcpv6_ia_addr *addr = (void*)&odata[-4];
-               set_rtnetlink_addr(ifindex, &addr->addr, 0, 0);
-       }
+       na_mode = na;
+       pd_mode = pd;
 }
 
 
@@ -179,35 +202,84 @@ static void dhcpv6_send(enum dhcpv6_msg type, uint8_t trid[3], uint32_t ecs)
        void *srv_id = odhcp6c_get_state(STATE_SERVER_ID, &srv_id_len);
 
        // Build IA_PDs
-       size_t ia_pd_len;
-       void *ia_pd = odhcp6c_get_state(STATE_IA_PD, &ia_pd_len);
+       size_t ia_pd_entries, ia_pd_len = 0;
+       struct odhcp6c_entry *e = odhcp6c_get_state(STATE_IA_PD, &ia_pd_entries);
+       ia_pd_entries /= sizeof(*e);
        struct dhcpv6_ia_hdr hdr_ia_pd = {
                htons(DHCPV6_OPT_IA_PD),
-               htons(sizeof(hdr_ia_pd) - 4 + ia_pd_len),
+               htons(sizeof(hdr_ia_pd) - 4),
                1, 0, 0
        };
 
+
+       uint8_t *ia_pd = alloca(ia_pd_entries * (sizeof(struct dhcpv6_ia_prefix) + 10));
+       for (size_t i = 0; i < ia_pd_entries; ++i) {
+               uint8_t ex_len = 0;
+               if (e[i].priority > 0)
+                       ex_len = ((e[i].priority - e[i].length - 1) / 8) + 6;
+
+               struct dhcpv6_ia_prefix p = {
+                       .type = htons(DHCPV6_OPT_IA_PREFIX),
+                       .len = htons(sizeof(p) - 4U + ex_len),
+                       .prefix = e[i].length,
+                       .addr = e[i].target
+               };
+
+               memcpy(ia_pd + ia_pd_len, &p, sizeof(p));
+               ia_pd_len += sizeof(p);
+
+               if (ex_len) {
+                       ia_pd[ia_pd_len++] = 0;
+                       ia_pd[ia_pd_len++] = DHCPV6_OPT_PD_EXCLUDE;
+                       ia_pd[ia_pd_len++] = 0;
+                       ia_pd[ia_pd_len++] = ex_len - 4;
+                       ia_pd[ia_pd_len++] = e[i].priority;
+
+                       uint32_t excl = ntohl(e[i].router.s6_addr32[1]);
+                       excl >>= (64 - e[i].priority);
+                       excl <<= 8 - ((e[i].priority - e[i].length) % 8);
+
+                       for (size_t i = ex_len - 5; i > 0; --i, excl >>= 8)
+                               ia_pd[ia_pd_len + i] = excl & 0xff;
+                       ia_pd_len += ex_len - 5;
+               }
+       }
+
        struct dhcpv6_ia_prefix pref = {
                .type = htons(DHCPV6_OPT_IA_PREFIX),
                .len = htons(25), .prefix = request_prefix
        };
-
-       if (ia_pd_len == 0 && request_prefix > 0 &&
-                       (type == DHCPV6_MSG_SOLICIT ||
-                       type == DHCPV6_MSG_REQUEST)) {
-               ia_pd = &pref;
+       if (request_prefix > 0 && ia_pd_len == 0 && type == DHCPV6_MSG_SOLICIT) {
+               ia_pd = (uint8_t*)&pref;
                ia_pd_len = sizeof(pref);
        }
+       hdr_ia_pd.len = htons(ntohs(hdr_ia_pd.len) + ia_pd_len);
 
        // Build IA_NAs
-       size_t ia_na_len;
-       void *ia_na = odhcp6c_get_state(STATE_IA_NA, &ia_na_len);
+       size_t ia_na_entries, ia_na_len = 0;
+       void *ia_na = NULL;
+       e = odhcp6c_get_state(STATE_IA_NA, &ia_na_entries);
+       ia_na_entries /= sizeof(*e);
+
        struct dhcpv6_ia_hdr hdr_ia_na = {
                htons(DHCPV6_OPT_IA_NA),
-               htons(sizeof(hdr_ia_na) - 4 + ia_na_len),
+               htons(sizeof(hdr_ia_na) - 4),
                1, 0, 0
        };
 
+       struct dhcpv6_ia_addr pa[ia_na_entries];
+       for (size_t i = 0; i < ia_na_entries; ++i) {
+               pa[i].type = htons(DHCPV6_OPT_IA_ADDR);
+               pa[i].len = htons(sizeof(pa[i]) - 4U);
+               pa[i].addr = e[i].target;
+               pa[i].preferred = 0;
+               pa[i].valid = 0;
+       }
+
+       ia_na = pa;
+       ia_na_len = sizeof(pa);
+       hdr_ia_na.len = htons(ntohs(hdr_ia_na.len) + ia_na_len);
+
        // Reconfigure Accept
        struct {
                uint16_t type;
@@ -241,7 +313,7 @@ static void dhcpv6_send(enum dhcpv6_msg type, uint8_t trid[3], uint32_t ecs)
                {&oro_refresh, 0},
                {cl_id, cl_id_len},
                {srv_id, srv_id_len},
-               {&reconf_accept, 0},
+               {&reconf_accept, sizeof(reconf_accept)},
                {&fqdn, fqdn_len},
                {&hdr_ia_na, sizeof(hdr_ia_na)},
                {ia_na, ia_na_len},
@@ -259,9 +331,8 @@ static void dhcpv6_send(enum dhcpv6_msg type, uint8_t trid[3], uint32_t ecs)
        }
 
        // Disable IAs if not used
-       if (type == DHCPV6_MSG_SOLICIT) {
-               iov[5].iov_len = sizeof(reconf_accept);
-       } else if (type != DHCPV6_MSG_REQUEST) {
+       if (type != DHCPV6_MSG_SOLICIT) {
+               iov[5].iov_len = 0;
                if (ia_na_len == 0)
                        iov[7].iov_len = 0;
                if (ia_pd_len == 0)
@@ -282,15 +353,15 @@ static void dhcpv6_send(enum dhcpv6_msg type, uint8_t trid[3], uint32_t ecs)
 static int64_t dhcpv6_rand_delay(int64_t time)
 {
        int random;
-       read(urandom_fd, &random, sizeof(random));
-       return (time * (random % 1000)) / 10000;
+       odhcp6c_random(&random, sizeof(random));
+       return (time * ((int64_t)random % 1000LL)) / 10000LL;
 }
 
 
 int dhcpv6_request(enum dhcpv6_msg type)
 {
        uint8_t buf[1536];
-       uint32_t timeout = UINT32_MAX;
+       uint64_t timeout = UINT32_MAX;
        struct dhcpv6_retx *retx = &dhcpv6_retx[type];
 
        if (retx->delay) {
@@ -299,25 +370,28 @@ int dhcpv6_request(enum dhcpv6_msg type)
                nanosleep(&ts, NULL);
        }
 
-       if (type == DHCPV6_MSG_RELEASE || type == DHCPV6_MSG_DECLINE)
+       if (type == DHCPV6_MSG_REQUEST)
+               timeout = 60;
+       else if (type == DHCPV6_MSG_RELEASE || type == DHCPV6_MSG_DECLINE)
                timeout = 3;
        else if (type == DHCPV6_MSG_UNKNOWN)
                timeout = t1;
        else if (type == DHCPV6_MSG_RENEW)
-               timeout = t2 - t1;
+               timeout = (t2 > t1) ? t2 - t1 : 0;
        else if (type == DHCPV6_MSG_REBIND)
-               timeout = t3 - t2;
+               timeout = (t3 > t2) ? t3 - t2 : 0;
 
        if (timeout == 0)
                return -1;
 
-       syslog(LOG_NOTICE, "Sending %s (timeout %us)", retx->name, timeout);
+       syslog(LOG_NOTICE, "Sending %s (timeout %us)", retx->name, (unsigned)timeout);
 
        uint64_t start = odhcp6c_get_milli_time(), round_start = start, elapsed;
 
        // Generate transaction ID
-       uint8_t trid[3];
-       read(urandom_fd, trid, sizeof(trid));
+       uint8_t trid[3] = {0, 0, 0};
+       if (type != DHCPV6_MSG_UNKNOWN)
+               odhcp6c_random(trid, sizeof(trid));
        ssize_t len = -1;
        int64_t rto = 0;
 
@@ -346,7 +420,7 @@ int dhcpv6_request(enum dhcpv6_msg type)
                for (; len < 0 && round_start < round_end;
                                round_start = odhcp6c_get_milli_time()) {
                        // Check for pending signal
-                       if (odhcp6c_signal_is_pending())
+                       if (odhcp6c_signal_process())
                                return -1;
 
                        // Set timeout for receiving
@@ -371,14 +445,17 @@ int dhcpv6_request(enum dhcpv6_msg type)
                                                "%ums", (unsigned)elapsed);
 
                                if (retx->handler_reply)
-                                       len = retx->handler_reply(type,
-                                               opt, opt_end, elapsed / 1000);
+                                       len = retx->handler_reply(
+                                                       type, opt, opt_end);
+
+                               if (len > 0 && round_end - round_start > 1000)
+                                       round_end = 1000 + round_start;
                        }
                }
 
                // Allow
                if (retx->handler_finish)
-                       len = retx->handler_finish(elapsed / 1000);
+                       len = retx->handler_finish();
        } while (len < 0 && elapsed / 1000 < timeout);
 
        return len;
@@ -406,19 +483,55 @@ static bool dhcpv6_response_is_valid(const void *buf, ssize_t len,
 
        uint8_t *end = ((uint8_t*)buf) + len, *odata;
        uint16_t otype, olen;
-       bool clientid_ok = false, serverid_ok = false;
+       bool clientid_ok = false, serverid_ok = false, rcauth_ok = false;
 
        size_t client_id_len, server_id_len;
        void *client_id = odhcp6c_get_state(STATE_CLIENT_ID, &client_id_len);
        void *server_id = odhcp6c_get_state(STATE_SERVER_ID, &server_id_len);
 
-       dhcpv6_for_each_option(&rep[1], end, otype, olen, odata)
-               if (otype == DHCPV6_OPT_CLIENTID)
+       dhcpv6_for_each_option(&rep[1], end, otype, olen, odata) {
+               if (otype == DHCPV6_OPT_CLIENTID) {
                        clientid_ok = (olen + 4U == client_id_len) && !memcmp(
                                        &odata[-4], client_id, client_id_len);
-               else if (otype == DHCPV6_OPT_SERVERID)
+               } else if (otype == DHCPV6_OPT_SERVERID) {
                        serverid_ok = (olen + 4U == server_id_len) && !memcmp(
                                        &odata[-4], server_id, server_id_len);
+               } else if (otype == DHCPV6_OPT_AUTH && olen == -4 +
+                               sizeof(struct dhcpv6_auth_reconfigure)) {
+                       struct dhcpv6_auth_reconfigure *r = (void*)&odata[-4];
+                       if (r->protocol != 3 || r->algorithm != 1 || r->reconf_type != 2)
+                               continue;
+
+                       md5_state_t md5;
+                       uint8_t serverhash[16], secretbytes[16], hash[16];
+                       memcpy(serverhash, r->key, sizeof(serverhash));
+                       memset(r->key, 0, sizeof(r->key));
+                       memcpy(secretbytes, reconf_key, sizeof(secretbytes));
+
+                       for (size_t i = 0; i < sizeof(secretbytes); ++i)
+                               secretbytes[i] ^= 0x36;
+
+                       md5_init(&md5);
+                       md5_append(&md5, secretbytes, sizeof(secretbytes));
+                       md5_append(&md5, buf, len);
+                       md5_finish(&md5, hash);
+
+                       for (size_t i = 0; i < sizeof(secretbytes); ++i) {
+                               secretbytes[i] ^= 0x36;
+                               secretbytes[i] ^= 0x5c;
+                       }
+
+                       md5_init(&md5);
+                       md5_append(&md5, secretbytes, sizeof(secretbytes));
+                       md5_append(&md5, hash, 16);
+                       md5_finish(&md5, hash);
+
+                       rcauth_ok = !memcmp(hash, serverhash, sizeof(hash));
+               }
+       }
+
+       if (rep->msg_type == DHCPV6_MSG_RECONF && !rcauth_ok)
+               return false;
 
        return clientid_ok && (serverid_ok || server_id_len == 0);
 }
@@ -435,7 +548,7 @@ int dhcpv6_poll_reconfigure(void)
 
 
 static int dhcpv6_handle_reconfigure(_unused enum dhcpv6_msg orig,
-               const void *opt, const void *end, uint32_t elapsed)
+               const void *opt, const void *end)
 {
        // TODO: should verify the reconfigure message
        uint16_t otype, olen;
@@ -446,74 +559,91 @@ static int dhcpv6_handle_reconfigure(_unused enum dhcpv6_msg orig,
                                odata[0] == DHCPV6_MSG_INFO_REQ))
                        msg = odata[0];
 
-       t1 -= elapsed;
-       t2 -= elapsed;
-       t3 -= elapsed;
-
-       if (t1 < 0)
-               t1 = 0;
-
-       if (t2 < 0)
-               t2 = 0;
-
-       if (t3 < 0)
-               t3 = 0;
-
-       dhcpv6_handle_reply(DHCPV6_MSG_UNKNOWN, NULL, NULL, elapsed);
+       dhcpv6_handle_reply(DHCPV6_MSG_UNKNOWN, NULL, NULL);
        return msg;
 }
 
 
 // Collect all advertised servers
-static int dhcpv6_handle_advert(_unused enum dhcpv6_msg orig,
-               const void *opt, const void *end, _unused uint32_t elapsed)
+static int dhcpv6_handle_advert(enum dhcpv6_msg orig,
+               const void *opt, const void *end)
 {
        uint16_t olen, otype;
        uint8_t *odata;
-       struct dhcpv6_server_cand cand = {false, false, 0, 0, {0}};
+       struct dhcpv6_server_cand cand = {false, false, 0, 0, {0}, NULL, NULL, 0, 0};
+       bool have_na = false;
+       int have_pd = 0;
 
        dhcpv6_for_each_option(opt, end, otype, olen, odata) {
+               if (orig == DHCPV6_MSG_SOLICIT &&
+                               (otype == DHCPV6_OPT_IA_PD || otype == DHCPV6_OPT_IA_NA) &&
+                               olen > sizeof(struct dhcpv6_ia_hdr)) {
+                       struct dhcpv6_ia_hdr *ia_hdr = (void*)(&odata[-4]);
+                       dhcpv6_parse_ia(&ia_hdr[1], odata + olen);
+               }
+
                if (otype == DHCPV6_OPT_SERVERID && olen <= 130) {
                        memcpy(cand.duid, odata, olen);
                        cand.duid_len = olen;
-               } else if (otype == DHCPV6_OPT_STATUS && olen >= 2 && !odata[0]
-                               && odata[1] == DHCPV6_NoAddrsAvail) {
-                       if (na_mode == IA_MODE_FORCE) {
-                               return -1;
-                       } else {
-                               cand.has_noaddravail = true;
-                               cand.preference -= 1000;
-                       }
                } else if (otype == DHCPV6_OPT_STATUS && olen >= 2 && !odata[0]
                                && odata[1] == DHCPV6_NoPrefixAvail) {
                        cand.preference -= 2000;
                } else if (otype == DHCPV6_OPT_PREF && olen >= 1 &&
                                cand.preference >= 0) {
-                       cand.preference = odata[1];
+                       cand.preference = odata[0];
                } else if (otype == DHCPV6_OPT_RECONF_ACCEPT) {
                        cand.wants_reconfigure = true;
                } else if (otype == DHCPV6_OPT_IA_PD && request_prefix) {
-                       struct dhcpv6_ia_hdr *h = (void*)odata;
+                       struct dhcpv6_ia_hdr *h = (struct dhcpv6_ia_hdr*)&odata[-4];
                        uint8_t *oend = odata + olen, *d;
                        dhcpv6_for_each_option(&h[1], oend, otype, olen, d) {
-                               if (otype == DHCPV6_OPT_IA_PREFIX)
-                                       cand.preference += 2000;
-                               else if (otype == DHCPV6_OPT_STATUS &&
-                                               olen >= 2 && d[0] == 0 &&
-                                               d[1] == DHCPV6_NoPrefixAvail)
-                                       cand.preference -= 2000;
+                               if (otype == DHCPV6_OPT_IA_PREFIX && (olen + 4) >=
+                                               (uint16_t)sizeof(struct dhcpv6_ia_prefix)) {
+                                       struct dhcpv6_ia_prefix *p = (struct dhcpv6_ia_prefix*)&d[-4];
+                                       have_pd = p->prefix;
+                               }
                        }
+               } else if (otype == DHCPV6_OPT_IA_NA) {
+                       struct dhcpv6_ia_hdr *h = (struct dhcpv6_ia_hdr*)&odata[-4];
+                       uint8_t *oend = odata + olen, *d;
+                       dhcpv6_for_each_option(&h[1], oend, otype, olen, d)
+                               if (otype == DHCPV6_OPT_IA_ADDR)
+                                       have_na = true;
                }
        }
 
-       if (cand.duid_len > 0)
+       if ((!have_na && na_mode == IA_MODE_FORCE) ||
+                       (!have_pd && pd_mode == IA_MODE_FORCE))
+               return -1;
+
+       if (na_mode != IA_MODE_NONE && !have_na) {
+               cand.has_noaddravail = true;
+               cand.preference -= 1000;
+       }
+
+       if (pd_mode != IA_MODE_NONE) {
+               if (have_pd)
+                       cand.preference += 2000 + (128 - have_pd);
+               else
+                       cand.preference -= 2000;
+       }
+
+       if (cand.duid_len > 0) {
+               cand.ia_na = odhcp6c_move_state(STATE_IA_NA, &cand.ia_na_len);
+               cand.ia_pd = odhcp6c_move_state(STATE_IA_PD, &cand.ia_pd_len);
                odhcp6c_add_state(STATE_SERVER_CAND, &cand, sizeof(cand));
+       }
+
+       if (orig == DHCPV6_MSG_SOLICIT) {
+               odhcp6c_clear_state(STATE_IA_NA);
+               odhcp6c_clear_state(STATE_IA_PD);
+       }
 
        return -1;
 }
 
 
-static int dhcpv6_commit_advert(_unused uint32_t elapsed)
+static int dhcpv6_commit_advert(void)
 {
        size_t cand_len;
        struct dhcpv6_server_cand *c = NULL, *cand =
@@ -540,8 +670,14 @@ static int dhcpv6_commit_advert(_unused uint32_t elapsed)
                odhcp6c_add_state(STATE_SERVER_ID, hdr, sizeof(hdr));
                odhcp6c_add_state(STATE_SERVER_ID, c->duid, c->duid_len);
                accept_reconfig = c->wants_reconfigure;
+               odhcp6c_add_state(STATE_IA_NA, c->ia_na, c->ia_na_len);
+               odhcp6c_add_state(STATE_IA_PD, c->ia_pd, c->ia_pd_len);
        }
 
+       for (size_t i = 0; i < cand_len / sizeof(*c); ++i) {
+               free(cand[i].ia_na);
+               free(cand[i].ia_pd);
+       }
        odhcp6c_clear_state(STATE_SERVER_CAND);
 
        if (!c)
@@ -554,53 +690,63 @@ static int dhcpv6_commit_advert(_unused uint32_t elapsed)
 
 
 static int dhcpv6_handle_rebind_reply(enum dhcpv6_msg orig,
-               const void *opt, const void *end, uint32_t elapsed)
+               const void *opt, const void *end)
 {
-       dhcpv6_handle_advert(orig, opt, end, elapsed);
-       if (dhcpv6_commit_advert(elapsed) < 0)
+       dhcpv6_handle_advert(orig, opt, end);
+       if (dhcpv6_commit_advert() < 0) {
+               dhcpv6_handle_reply(DHCPV6_MSG_UNKNOWN, NULL, NULL);
                return -1;
+       }
 
-       return dhcpv6_handle_reply(orig, opt, end, elapsed);
+       return dhcpv6_handle_reply(orig, opt, end);
 }
 
 
-static int dhcpv6_handle_reply(_unused enum dhcpv6_msg orig,
-               const void *opt, const void *end, uint32_t elapsed)
+static int dhcpv6_handle_reply(enum dhcpv6_msg orig,
+               const void *opt, const void *end)
 {
-       uint16_t otype, olen;
        uint8_t *odata;
-       bool have_update = false;
-
-       t1 = t2 = t3 = 86400;
-
-       size_t ia_na_len, dns_len, search_len, sntp_ip_len, sntp_dns_len;
-       uint8_t *ia_na = odhcp6c_get_state(STATE_IA_NA, &ia_na_len);
-       uint8_t *ia_end;
-       odhcp6c_get_state(STATE_DNS, &dns_len);
-       odhcp6c_get_state(STATE_SEARCH, &search_len);
-       odhcp6c_get_state(STATE_SNTP_IP, &sntp_ip_len);
-       odhcp6c_get_state(STATE_SNTP_FQDN, &sntp_dns_len);
-
-       // Decrease valid and preferred lifetime of prefixes
-       size_t ia_pd_len;
-       uint8_t *ia_pd = odhcp6c_get_state(STATE_IA_PD, &ia_pd_len);
-       dhcpv6_for_each_option(ia_pd, ia_pd + ia_pd_len, otype, olen, odata) {
-               struct dhcpv6_ia_prefix *p = (void*)&odata[-4];
-               uint32_t valid = ntohl(p->valid);
-               p->valid = (valid < elapsed) ? 0 : htonl(valid - elapsed);
-
-               uint32_t pref = ntohl(p->preferred);
-               p->preferred = (pref < elapsed) ? 0 : htonl(pref - elapsed);
+       uint16_t otype, olen;
+
+       odhcp6c_expire();
+
+       if (orig == DHCPV6_MSG_UNKNOWN) {
+               static time_t last_update = 0;
+               time_t now = odhcp6c_get_milli_time() / 1000;
+
+               uint32_t elapsed = (last_update > 0) ? now - last_update : 0;
+               last_update = now;
+
+               t1 -= elapsed;
+               t2 -= elapsed;
+               t3 -= elapsed;
+
+               if (t1 < 0)
+                       t1 = 0;
+
+               if (t2 < 0)
+                       t2 = 0;
+
+               if (t3 < 0)
+                       t3 = 0;
+       } else {
+               t1 = t2 = t3 = UINT32_MAX;
        }
 
-       // Decrease valid and preferred lifetime of addresses
-       dhcpv6_for_each_option(ia_na, ia_na + ia_na_len, otype, olen, odata) {
-               struct dhcpv6_ia_addr *p = (void*)&odata[-4];
-               uint32_t valid = ntohl(p->valid);
-               p->valid = (valid < elapsed) ? 0 : htonl(valid - elapsed);
+       if (orig == DHCPV6_MSG_REQUEST) {
+               // Delete NA and PD we have in the state from the Advert
+               odhcp6c_clear_state(STATE_IA_NA);
+               odhcp6c_clear_state(STATE_IA_PD);
+       }
 
-               uint32_t pref = ntohl(p->preferred);
-               p->preferred = (pref < elapsed) ? 0 : htonl(pref - elapsed);
+       if (opt) {
+               odhcp6c_clear_state(STATE_DNS);
+               odhcp6c_clear_state(STATE_SEARCH);
+               odhcp6c_clear_state(STATE_SNTP_IP);
+               odhcp6c_clear_state(STATE_SNTP_FQDN);
+               odhcp6c_clear_state(STATE_SIP_IP);
+               odhcp6c_clear_state(STATE_SIP_FQDN);
+               odhcp6c_clear_state(STATE_AFTR_NAME);
        }
 
        // Parse and find all matching IAs
@@ -608,21 +754,39 @@ static int dhcpv6_handle_reply(_unused enum dhcpv6_msg orig,
                if ((otype == DHCPV6_OPT_IA_PD || otype == DHCPV6_OPT_IA_NA)
                                && olen > sizeof(struct dhcpv6_ia_hdr)) {
                        struct dhcpv6_ia_hdr *ia_hdr = (void*)(&odata[-4]);
-                       time_t l_t1 = ntohl(ia_hdr->t1);
-                       time_t l_t2 = ntohl(ia_hdr->t2);
+                       uint32_t l_t1 = ntohl(ia_hdr->t1);
+                       uint32_t l_t2 = ntohl(ia_hdr->t2);
 
                        // Test ID and T1-T2 validity
                        if (ia_hdr->iaid != 1 || l_t2 < l_t1)
                                continue;
 
+                       int error = 0;
                        uint16_t stype, slen;
                        uint8_t *sdata;
                        // Test status and bail if error
                        dhcpv6_for_each_option(&ia_hdr[1], odata + olen,
                                        stype, slen, sdata)
-                               if (stype == DHCPV6_OPT_STATUS && slen >= 2 &&
-                                               (sdata[0] || sdata[1]))
-                                       continue;
+                               if (stype == DHCPV6_OPT_STATUS && slen >= 2)
+                                       error = ((int)sdata[0]) << 8 | ((int)sdata[1]);
+
+                       if (error) {
+                               syslog(LOG_WARNING, "Server returned IAID status %i!", error);
+                               if (error != 2)
+                                       raise(SIGUSR2);
+                               break;
+                       }
+
+                       uint32_t n = dhcpv6_parse_ia(&ia_hdr[1], odata + olen);
+
+                       if (!l_t1)
+                               l_t1 = 300;
+
+                       if (!l_t2)
+                               l_t2 = 600;
+
+                       if (n < t3)
+                               t3 = n;
 
                        // Update times
                        if (l_t1 > 0 && t1 > l_t1)
@@ -631,24 +795,9 @@ static int dhcpv6_handle_reply(_unused enum dhcpv6_msg orig,
                        if (l_t2 > 0 && t2 > l_t2)
                                t2 = l_t2;
 
-                       // Always report update in case we have IA_PDs so that
-                       // the state-script is called with updated times
-                       if (otype == DHCPV6_OPT_IA_PD && request_prefix)
-                               have_update = true;
-
-                       time_t n = dhcpv6_parse_ia(&ia_hdr[1], odata + olen);
-
-                       if (n < t1)
-                               t1 = n;
-
-                       if (n < t2)
-                               t2 = n;
-
-                       if (n < t3)
-                               t3 = n;
-
                } else if (otype == DHCPV6_OPT_DNS_SERVERS) {
-                       odhcp6c_add_state(STATE_DNS, odata, olen);
+                       if (olen % 16 == 0)
+                               odhcp6c_add_state(STATE_DNS, odata, olen);
                } else if (otype == DHCPV6_OPT_DNS_DOMAIN) {
                        odhcp6c_add_state(STATE_SEARCH, odata, olen);
                } else if (otype == DHCPV6_OPT_NTP_SERVER) {
@@ -665,10 +814,26 @@ static int dhcpv6_handle_reply(_unused enum dhcpv6_msg orig,
                                        odhcp6c_add_state(STATE_SNTP_FQDN,
                                                        sdata, slen);
                        }
+               } else if (otype == DHCPV6_OPT_SIP_SERVER_A) {
+                       if (olen == 16)
+                               odhcp6c_add_state(STATE_SIP_IP, odata, olen);
+               } else if (otype == DHCPV6_OPT_SIP_SERVER_D) {
+                       odhcp6c_add_state(STATE_SIP_FQDN, odata, olen);
                } else if (otype == DHCPV6_OPT_INFO_REFRESH && olen >= 4) {
                        uint32_t refresh = ntohl(*((uint32_t*)odata));
                        if (refresh < (uint32_t)t1)
                                t1 = refresh;
+               } else if (otype == DHCPV6_OPT_AUTH && olen == -4 +
+                               sizeof(struct dhcpv6_auth_reconfigure)) {
+                       struct dhcpv6_auth_reconfigure *r = (void*)&odata[-4];
+                       if (r->protocol == 3 && r->algorithm == 1 &&
+                                       r->reconf_type == 1)
+                               memcpy(reconf_key, r->key, sizeof(r->key));
+               } else if (otype == DHCPV6_OPT_AFTR_NAME && olen > 3) {
+                       size_t cur_len;
+                       odhcp6c_get_state(STATE_AFTR_NAME, &cur_len);
+                       if (cur_len == 0)
+                               odhcp6c_add_state(STATE_AFTR_NAME, odata, olen);
                } else if (otype != DHCPV6_OPT_CLIENTID &&
                                otype != DHCPV6_OPT_SERVERID) {
                        odhcp6c_add_state(STATE_CUSTOM_OPTS,
@@ -676,131 +841,124 @@ static int dhcpv6_handle_reply(_unused enum dhcpv6_msg orig,
                }
        }
 
-       if (opt) {
-               have_update |= odhcp6c_commit_state(STATE_DNS, dns_len);
-               have_update |= odhcp6c_commit_state(STATE_SEARCH, search_len);
-               have_update |= odhcp6c_commit_state(STATE_SNTP_IP,
-                               sntp_ip_len);
-               have_update |= odhcp6c_commit_state(STATE_SNTP_FQDN,
-                               sntp_dns_len);
-               size_t new_ia_pd_len, new_ia_na_len;
-               odhcp6c_get_state(STATE_IA_PD, &new_ia_pd_len);
-               odhcp6c_get_state(STATE_IA_NA, &new_ia_na_len);
-               have_update |= (new_ia_pd_len != ia_pd_len) ||
-                               (new_ia_na_len != ia_na_len);
-       }
-
-       // Delete prefixes with 0 valid-time
-       ia_pd = odhcp6c_get_state(STATE_IA_PD, &ia_pd_len);
-       ia_end = ia_pd + ia_pd_len;
-       dhcpv6_for_each_option(ia_pd, ia_end, otype, olen, odata) {
-               struct dhcpv6_ia_prefix *p = (void*)&odata[-4];
-               while (!p->valid) {
-                       ia_end = ia_pd + odhcp6c_remove_state(STATE_IA_PD,
-                                       (uint8_t*)p - ia_pd, olen + 4);
-                       have_update = true;
-               }
-       }
+       if (t1 == UINT32_MAX)
+               t1 = 300;
 
+       if (t2 == UINT32_MAX)
+               t2 = 600;
 
-       // Delete addresses with 0 valid-time
-       ia_na = odhcp6c_get_state(STATE_IA_NA, &ia_na_len);
-       ia_end = ia_na + ia_na_len;
-       dhcpv6_for_each_option(ia_na, ia_end, otype, olen, odata) {
-               struct dhcpv6_ia_addr *p = (void*)&odata[-4];
-               while (!p->valid) {
-                       ia_end = ia_na + odhcp6c_remove_state(STATE_IA_NA,
-                                       (uint8_t*)p - ia_na, olen + 4);
-                       have_update = true;
-               }
-       }
+       if (t3 == UINT32_MAX)
+               t3 = 3600;
 
-       return have_update;
+       return true;
 }
 
 
-static time_t dhcpv6_parse_ia(void *opt, void *end)
+static uint32_t dhcpv6_parse_ia(void *opt, void *end)
 {
        uint32_t timeout = UINT32_MAX; // Minimum timeout
-       uint16_t otype, olen, stype, slen;
-       uint8_t *odata, *sdata;
+       uint16_t otype, olen;
+       uint8_t *odata;
 
        // Update address IA
        dhcpv6_for_each_option(opt, end, otype, olen, odata) {
+               struct odhcp6c_entry entry = {IN6ADDR_ANY_INIT, 0, 0,
+                               IN6ADDR_ANY_INIT, 0, 0, 0};
+
                if (otype == DHCPV6_OPT_IA_PREFIX) {
                        struct dhcpv6_ia_prefix *prefix = (void*)&odata[-4];
                        if (olen + 4U < sizeof(*prefix))
                                continue;
 
-                       olen = sizeof(*prefix); // Normalize length
-                       uint32_t valid = ntohl(prefix->valid);
-                       uint32_t pref = ntohl(prefix->preferred);
+                       entry.valid = ntohl(prefix->valid);
+                       entry.preferred = ntohl(prefix->preferred);
 
-                       if (pref > valid)
+                       if (entry.preferred > entry.valid)
                                continue;
 
-                       // Search matching IA
-                       struct dhcpv6_ia_prefix *local = NULL;
-                       size_t pd_len;
-                       uint8_t *pd = odhcp6c_get_state(STATE_IA_PD, &pd_len);
-                       dhcpv6_for_each_option(pd, pd + pd_len,
+                       entry.length = prefix->prefix;
+                       entry.target = prefix->addr;
+                       uint16_t stype, slen;
+                       uint8_t *sdata;
+
+#ifdef EXT_PREFIX_CLASS
+                        // Find prefix class, if any
+                       dhcpv6_for_each_option(&prefix[1], odata + olen,
                                        stype, slen, sdata)
-                               if (!memcmp(sdata + 8, odata + 8,
-                                               sizeof(local->addr) + 1))
-                                       local = (void*)&sdata[-4];
-
-                       if (local) { // Already know that IA
-                               local->preferred = prefix->preferred;
-                               local->valid = prefix->valid;
-                       } else { // New IA
-                               odhcp6c_add_state(STATE_IA_PD, prefix, olen);
+                               if (stype == DHCPV6_OPT_PREFIX_CLASS && slen == 2)
+                                       entry.class = sdata[0] << 8 | sdata[1];
+#endif
+
+                       // Parse PD-exclude
+                       bool ok = true;
+                       dhcpv6_for_each_option(odata + sizeof(*prefix) - 4U,
+                                       odata + olen, stype, slen, sdata) {
+                               if (stype != DHCPV6_OPT_PD_EXCLUDE || slen < 2)
+                                       continue;
+
+                               uint8_t elen = sdata[0];
+                               if (elen > 64)
+                                       elen = 64;
+
+                               if (elen <= 32 || elen <= entry.length) {
+                                       ok = false;
+                                       continue;
+                               }
+
+
+                               uint8_t bytes = ((elen - entry.length - 1) / 8) + 1;
+                               if (slen <= bytes) {
+                                       ok = false;
+                                       continue;
+                               }
+
+                               uint32_t exclude = 0;
+                               do {
+                                       exclude = exclude << 8 | sdata[bytes];
+                               } while (--bytes);
+
+                               exclude >>= 8 - ((elen - entry.length) % 8);
+                               exclude <<= 64 - elen;
+
+                               // Abusing router & priority fields for exclusion
+                               entry.router = entry.target;
+                               entry.router.s6_addr32[1] |= htonl(exclude);
+                               entry.priority = elen;
                        }
 
-                       if (timeout > valid)
-                               timeout = valid;
+                       if (ok)
+                               odhcp6c_update_entry(STATE_IA_PD, &entry);
 
-                       if (prefix->valid == 0) // We probably lost that prefix
-                               odhcp6c_add_state(STATE_IA_PD_LOST,
-                                               prefix, olen);
+                       entry.priority = 0;
+                       memset(&entry.router, 0, sizeof(entry.router));
                } else if (otype == DHCPV6_OPT_IA_ADDR) {
                        struct dhcpv6_ia_addr *addr = (void*)&odata[-4];
                        if (olen + 4U < sizeof(*addr))
                                continue;
 
-                       olen = sizeof(*addr); // Normalize length
-                       uint32_t pref = ntohl(addr->preferred);
-                       uint32_t valid = ntohl(addr->valid);
+                       entry.preferred = ntohl(addr->preferred);
+                       entry.valid = ntohl(addr->valid);
 
-                       if (pref > valid)
+                       if (entry.preferred > entry.valid)
                                continue;
 
-                       // Search matching IA
-                       struct dhcpv6_ia_addr *local = NULL;
-                       size_t na_len;
-                       uint8_t *na = odhcp6c_get_state(STATE_IA_NA, &na_len);
-                       dhcpv6_for_each_option(na, na + na_len,
-                                       stype, slen, sdata)
-                               if (!memcmp(sdata, odata, sizeof(local->addr)))
-                                       local = (void*)&sdata[-4];
-
+                       entry.length = 128;
+                       entry.target = addr->addr;
 
-                       if (local) { // Already know that IA
-                               local->preferred = addr->preferred;
-                               local->valid = addr->valid;
-                       } else { // New IA
-                               odhcp6c_add_state(STATE_IA_NA, addr, olen);
-                       }
-
-
-                       if (timeout > valid)
-                               timeout = valid;
+#ifdef EXT_PREFIX_CLASS
+                       uint16_t stype, slen;
+                       uint8_t *sdata;
+                       // Find prefix class, if any
+                       dhcpv6_for_each_option(&addr[1], odata + olen,
+                                       stype, slen, sdata)
+                               if (stype == DHCPV6_OPT_PREFIX_CLASS && slen == 2)
+                                       entry.class = sdata[0] << 8 | sdata[1];
+#endif
 
-                       if (set_rtnetlink_addr(ifindex, &addr->addr,
-                                       pref, valid) == -EADDRNOTAVAIL) {
-                               dhcpv6_request(DHCPV6_MSG_DECLINE);
-                               raise(SIGUSR2);
-                       }
+                       odhcp6c_update_entry(STATE_IA_NA, &entry);
                }
+               if (entry.valid > 0 && timeout > entry.valid)
+                       timeout = entry.valid;
        }
 
        return timeout;