X-Git-Url: https://git.decadent.org.uk/gitweb/?p=odhcp6c.git;a=blobdiff_plain;f=src%2Fdhcpv6.c;h=7fdf4f68c6fcc46f292c65e19e5998ce858e457f;hp=9a451d0568232896c084ed33d3138f46a35f5e59;hb=8563be22c8d9e3cf38b26d69d52368c68ad3a6dd;hpb=4a58bef7322b830b2e87be39c611a1bf4845ef49 diff --git a/src/dhcpv6.c b/src/dhcpv6.c index 9a451d0..7fdf4f6 100644 --- a/src/dhcpv6.c +++ b/src/dhcpv6.c @@ -1,5 +1,5 @@ /** - * Copyright (C) 2012 Steven Barth + * Copyright (C) 2012-2013 Steven Barth * * 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 #include #include +#include #include #include #include @@ -25,12 +26,14 @@ #include #include #include +#include #include #include #include #include "odhcp6c.h" +#include "md5.h" #define ALL_DHCPV6_RELAYS {{{0xff, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,\ @@ -40,65 +43,85 @@ #define DHCPV6_DUID_LLADDR 3 #define DHCPV6_REQ_DELAY 1 +#define DHCPV6_SOL_MAX_RT_MIN 60 +#define DHCPV6_SOL_MAX_RT_MAX 86400 +#define DHCPV6_INF_MAX_RT_MIN 60 +#define DHCPV6_INF_MAX_RT_MAX 86400 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); + const uint8_t transaction[3], enum dhcpv6_msg type, + const struct in6_addr *daddr); + +static int dhcpv6_parse_ia(void *opt, void *end); + +static int dhcpv6_calc_refresh_timers(void); +static void dhcpv6_handle_status_code(_unused const enum dhcpv6_msg orig, + const uint16_t code, const void *status_msg, const int len, + int *ret); +static void dhcpv6_handle_ia_status_code(const enum dhcpv6_msg orig, + const struct dhcpv6_ia_hdr *ia_hdr, const uint16_t code, + const void *status_msg, const int len, + bool handled_status_codes[_DHCPV6_Status_Max], + int *ret); +static void dhcpv6_add_server_cand(const struct dhcpv6_server_cand *cand); +static void dhcpv6_clear_all_server_cand(void); 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); // RFC 3315 - 5.5 Timeout and Delay values static struct dhcpv6_retx dhcpv6_retx[_DHCPV6_MSG_MAX] = { - [DHCPV6_MSG_UNKNOWN] = {false, 1, 120, "", - 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_handle_reply, NULL}, - [DHCPV6_MSG_RENEW] = {false, 10, 600, "RENEW", - dhcpv6_handle_reply, NULL}, - [DHCPV6_MSG_REBIND] = {false, 10, 600, "REBIND", - dhcpv6_handle_rebind_reply, NULL}, - [DHCPV6_MSG_RELEASE] = {false, 1, 600, "RELEASE", NULL, NULL}, - [DHCPV6_MSG_DECLINE] = {false, 1, 3, "DECLINE", NULL, NULL}, - [DHCPV6_MSG_INFO_REQ] = {true, 1, 120, "INFOREQ", - dhcpv6_handle_reply, NULL}, + [DHCPV6_MSG_UNKNOWN] = {false, 1, 120, 0, "", + dhcpv6_handle_reconfigure, NULL}, + [DHCPV6_MSG_SOLICIT] = {true, 1, DHCPV6_SOL_MAX_RT, 0, "SOLICIT", + dhcpv6_handle_advert, dhcpv6_commit_advert}, + [DHCPV6_MSG_REQUEST] = {true, 1, DHCPV6_REQ_MAX_RT, 10, "REQUEST", + dhcpv6_handle_reply, NULL}, + [DHCPV6_MSG_RENEW] = {false, 10, DHCPV6_REN_MAX_RT, 0, "RENEW", + dhcpv6_handle_reply, NULL}, + [DHCPV6_MSG_REBIND] = {false, 10, DHCPV6_REB_MAX_RT, 0, "REBIND", + dhcpv6_handle_rebind_reply, NULL}, + [DHCPV6_MSG_RELEASE] = {false, 1, 0, 5, "RELEASE", NULL, NULL}, + [DHCPV6_MSG_DECLINE] = {false, 1, 0, 5, "DECLINE", NULL, NULL}, + [DHCPV6_MSG_INFO_REQ] = {true, 1, DHCPV6_INF_MAX_RT, 0, "INFOREQ", + dhcpv6_handle_reply, NULL}, }; // 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; +// Server unicast address +static struct in6_addr server_addr = IN6ADDR_ANY_INIT; +// 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); + if (sock < 0) + return -1; // Detect interface struct ifreq ifr; strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name)); - if (ioctl(sock, SIOCGIFINDEX, &ifr)) + if (ioctl(sock, SIOCGIFINDEX, &ifr) < 0) return -1; ifindex = ifr.ifr_ifindex; @@ -106,49 +129,77 @@ int init_dhcpv6(const char *ifname, int request_pd) size_t client_id_len; odhcp6c_get_state(STATE_CLIENT_ID, &client_id_len); if (client_id_len == 0) { - ioctl(sock, SIOCGIFHWADDR, &ifr); 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); + + if (ioctl(sock, SIOCGIFHWADDR, &ifr) >= 0) + 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, ETHER_ADDR_LEN); ifp++) { + memcpy(ifr.ifr_name, ifp->ifr_name, + sizeof(ifr.ifr_name)); + if (ioctl(sock, SIOCGIFHWADDR, &ifr) < 0) + continue; + + 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_UNICAST), + htons(DHCPV6_OPT_NTP_SERVER), + htons(DHCPV6_OPT_AFTR_NAME), + htons(DHCPV6_OPT_PD_EXCLUDE), + htons(DHCPV6_OPT_SOL_MAX_RT), + htons(DHCPV6_OPT_INF_MAX_RT), +#ifdef EXT_PREFIX_CLASS + htons(DHCPV6_OPT_PREFIX_CLASS), +#endif + }; odhcp6c_add_state(STATE_ORO, oro, sizeof(oro)); - // Configure IPv6-options int val = 1; setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY, &val, sizeof(val)); setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val)); + setsockopt(sock, IPPROTO_IPV6, IPV6_RECVPKTINFO, &val, sizeof(val)); + val = 0; + setsockopt(sock, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &val, sizeof(val)); setsockopt(sock, SOL_SOCKET, SO_BINDTODEVICE, ifname, strlen(ifname)); struct sockaddr_in6 client_addr = { .sin6_family = AF_INET6, .sin6_port = htons(DHCPV6_CLIENT_PORT), .sin6_flowinfo = 0 }; - if (bind(sock, (struct sockaddr*)&client_addr, sizeof(client_addr))) + if (bind(sock, (struct sockaddr*)&client_addr, sizeof(client_addr)) < 0) return -1; return 0; } -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 +230,84 @@ 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 +341,7 @@ 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 +359,8 @@ 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) @@ -275,22 +374,44 @@ static void dhcpv6_send(enum dhcpv6_msg type, uint8_t trid[3], uint32_t ecs) 0, ALL_DHCPV6_RELAYS, ifindex}; struct msghdr msg = {&srv, sizeof(srv), iov, cnt, NULL, 0, 0}; - sendmsg(sock, &msg, 0); + switch (type) { + case DHCPV6_MSG_REQUEST: + case DHCPV6_MSG_RENEW: + case DHCPV6_MSG_RELEASE: + case DHCPV6_MSG_DECLINE: + if (!IN6_IS_ADDR_UNSPECIFIED(&server_addr) && + odhcp6c_addr_in_scope(&server_addr)) { + srv.sin6_addr = server_addr; + if (!IN6_IS_ADDR_LINKLOCAL(&server_addr)) + srv.sin6_scope_id = 0; + } + break; + default: + break; + } + + if (sendmsg(sock, &msg, 0) < 0) { + char in6_str[INET6_ADDRSTRLEN]; + + syslog(LOG_ERR, "Failed to send DHCPV6 message to %s (%s)", + inet_ntop(AF_INET6, (const void *)&srv.sin6_addr, + in6_str, sizeof(in6_str)), strerror(errno)); + } } 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; + uint8_t rc = 0; + uint64_t timeout = UINT32_MAX; struct dhcpv6_retx *retx = &dhcpv6_retx[type]; if (retx->delay) { @@ -299,34 +420,42 @@ int dhcpv6_request(enum dhcpv6_msg type) nanosleep(&ts, NULL); } - if (type == DHCPV6_MSG_RELEASE || type == DHCPV6_MSG_DECLINE) - timeout = 3; - else if (type == DHCPV6_MSG_UNKNOWN) + 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, "Starting %s transaction (timeout %llus, max rc %d)", + retx->name, (unsigned long long)timeout, retx->max_rc); 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; do { - rto = (rto == 0) ? (retx->init_timeo * 1000 + - dhcpv6_rand_delay(retx->init_timeo * 1000)) : - (2 * rto + dhcpv6_rand_delay(rto)); + if (rto == 0) { + int64_t delay = dhcpv6_rand_delay(retx->init_timeo * 1000); + + // First RT MUST be strictly greater than IRT for solicit messages (RFC3313 17.1.2) + while (type == DHCPV6_MSG_SOLICIT && delay <= 0) + delay = dhcpv6_rand_delay(retx->init_timeo * 1000); - if (rto >= retx->max_timeo * 1000) + rto = (retx->init_timeo * 1000 + delay); + } + else + rto = (2 * rto + dhcpv6_rand_delay(rto)); + + if (retx->max_timeo && (rto >= retx->max_timeo * 1000)) rto = retx->max_timeo * 1000 + dhcpv6_rand_delay(retx->max_timeo * 1000); @@ -339,14 +468,25 @@ int dhcpv6_request(enum dhcpv6_msg type) round_end = timeout * 1000 + start; // Built and send package - if (type != DHCPV6_MSG_UNKNOWN) + if (type != DHCPV6_MSG_UNKNOWN) { + if (type != DHCPV6_MSG_SOLICIT) + syslog(LOG_NOTICE, "Send %s message (elapsed %llums, rc %d)", + retx->name, (unsigned long long)elapsed, rc); dhcpv6_send(type, trid, elapsed / 10); + rc++; + } // Receive rounds - for (; len < 0 && round_start < round_end; + for (; len < 0 && (round_start < round_end); round_start = odhcp6c_get_milli_time()) { + uint8_t buf[1536], cmsg_buf[CMSG_SPACE(sizeof(struct in6_pktinfo))]; + struct iovec iov = {buf, sizeof(buf)}; + struct msghdr msg = {NULL, 0, &iov, 1, + cmsg_buf, sizeof(cmsg_buf), 0}; + struct in6_pktinfo *pktinfo = NULL; + // Check for pending signal - if (odhcp6c_signal_is_pending()) + if (odhcp6c_signal_process()) return -1; // Set timeout for receiving @@ -356,37 +496,57 @@ int dhcpv6_request(enum dhcpv6_msg type) &timeout, sizeof(timeout)); // Receive cycle - len = recv(sock, buf, sizeof(buf), 0); + len = recvmsg(sock, &msg, 0); + if (len < 0) + continue; + + for (struct cmsghdr *ch = CMSG_FIRSTHDR(&msg); ch != NULL; + ch = CMSG_NXTHDR(&msg, ch)) { + if (ch->cmsg_level == SOL_IPV6 && + ch->cmsg_type == IPV6_PKTINFO) { + pktinfo = (struct in6_pktinfo *)CMSG_DATA(ch); + break; + } + } - if (!dhcpv6_response_is_valid(buf, len, trid, type)) + if (pktinfo == NULL) { len = -1; + continue; + } - if (len > 0) { - uint8_t *opt = &buf[4]; - uint8_t *opt_end = opt + len - 4; + if (!dhcpv6_response_is_valid(buf, len, trid, + type, &pktinfo->ipi6_addr)) { + len = -1; + continue; + } - round_start = odhcp6c_get_milli_time(); - elapsed = round_start - start; - syslog(LOG_NOTICE, "Got a valid reply after " - "%ums", (unsigned)elapsed); + uint8_t *opt = &buf[4]; + uint8_t *opt_end = opt + len - 4; - if (retx->handler_reply) - len = retx->handler_reply(type, - opt, opt_end, elapsed / 1000); - } + round_start = odhcp6c_get_milli_time(); + elapsed = round_start - start; + syslog(LOG_NOTICE, "Got a valid reply after " + "%llums", (unsigned long long)elapsed); + + if (retx->handler_reply) + len = retx->handler_reply(type, rc, 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); - } while (len < 0 && elapsed / 1000 < timeout); + len = retx->handler_finish(); + } while (len < 0 && ((elapsed / 1000 < timeout) && (!retx->max_rc || rc < retx->max_rc))); return len; } - +// Message validation checks according to RFC3315 chapter 15 static bool dhcpv6_response_is_valid(const void *buf, ssize_t len, - const uint8_t transaction[3], enum dhcpv6_msg type) + const uint8_t transaction[3], enum dhcpv6_msg type, + const struct in6_addr *daddr) { const struct dhcpv6_header *rep = buf; if (len < (ssize_t)sizeof(*rep) || memcmp(rep->tr_id, @@ -404,23 +564,85 @@ static bool dhcpv6_response_is_valid(const void *buf, ssize_t len, return false; } - uint8_t *end = ((uint8_t*)buf) + len, *odata; + uint8_t *end = ((uint8_t*)buf) + len, *odata, + rcmsg = DHCPV6_MSG_UNKNOWN; uint16_t otype, olen; - bool clientid_ok = false, serverid_ok = false; + bool clientid_ok = false, serverid_ok = false, rcauth_ok = false, + ia_present = false, options_valid = true; 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) - serverid_ok = (olen + 4U == server_id_len) && !memcmp( - &odata[-4], server_id, server_id_len); + } else if (otype == DHCPV6_OPT_SERVERID) { + if (server_id_len) + serverid_ok = (olen + 4U == server_id_len) && !memcmp( + &odata[-4], server_id, server_id_len); + else + serverid_ok = true; + } 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); - return clientid_ok && (serverid_ok || server_id_len == 0); + 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)); + } else if (otype == DHCPV6_OPT_RECONF_MESSAGE && olen == 1) { + rcmsg = odata[0]; + } else if ((otype == DHCPV6_OPT_IA_PD || otype == DHCPV6_OPT_IA_NA)) { + ia_present = true; + if (olen < sizeof(struct dhcpv6_ia_hdr)) + options_valid = false; + } + else if ((otype == DHCPV6_OPT_IA_ADDR) || (otype == DHCPV6_OPT_IA_PREFIX) || + (otype == DHCPV6_OPT_PD_EXCLUDE)) { + // Options are not allowed on global level + options_valid = false; + } + } + + if (!options_valid || ((odata + olen) > end)) + return false; + + if (type == DHCPV6_MSG_INFO_REQ && ia_present) + return false; + + if (rep->msg_type == DHCPV6_MSG_RECONF) { + if ((rcmsg != DHCPV6_MSG_RENEW && rcmsg != DHCPV6_MSG_INFO_REQ) || + (rcmsg == DHCPV6_MSG_INFO_REQ && ia_present) || + !rcauth_ok || IN6_IS_ADDR_MULTICAST(daddr)) + return false; + } + + return clientid_ok && serverid_ok; } @@ -434,10 +656,9 @@ int dhcpv6_poll_reconfigure(void) } -static int dhcpv6_handle_reconfigure(_unused enum dhcpv6_msg orig, - const void *opt, const void *end, uint32_t elapsed) +static int dhcpv6_handle_reconfigure(_unused enum dhcpv6_msg orig, const int rc, + const void *opt, const void *end) { - // TODO: should verify the reconfigure message uint16_t otype, olen; uint8_t *odata, msg = DHCPV6_MSG_RENEW; dhcpv6_for_each_option(opt, end, otype, olen, odata) @@ -446,164 +667,179 @@ 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, rc, 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 int rc, + const void *opt, const void *end) { uint16_t olen, otype; - uint8_t *odata; - struct dhcpv6_server_cand cand = {false, false, 0, 0, {0}}; + uint8_t *odata, pref = 0; + struct dhcpv6_server_cand cand = {false, false, 0, 0, {0}, + IN6ADDR_ANY_INIT, DHCPV6_SOL_MAX_RT, + DHCPV6_INF_MAX_RT, 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, odata + olen + sizeof(*ia_hdr)); + } + 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) { + int error = ((int)odata[0] << 8 | (int)odata[1]); + + switch (error) { + case DHCPV6_NoPrefixAvail: + // Status code on global level + cand.preference -= 2000; + break; + + default : + break; } - } 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 = pref = odata[0]; + } else if (otype == DHCPV6_OPT_UNICAST && olen == sizeof(cand.server_addr)) { + cand.server_addr = *(struct in6_addr *)odata; } else if (otype == DHCPV6_OPT_RECONF_ACCEPT) { cand.wants_reconfigure = true; + } else if (otype == DHCPV6_OPT_SOL_MAX_RT && olen == 4) { + uint32_t sol_max_rt = ntohl(*((uint32_t *)odata)); + if (sol_max_rt >= DHCPV6_SOL_MAX_RT_MIN && + sol_max_rt <= DHCPV6_SOL_MAX_RT_MAX) + cand.sol_max_rt = sol_max_rt; + } else if (otype == DHCPV6_OPT_INF_MAX_RT && olen == 4) { + uint32_t inf_max_rt = ntohl(*((uint32_t *)odata)); + if (inf_max_rt >= DHCPV6_INF_MAX_RT_MIN && + inf_max_rt <= DHCPV6_INF_MAX_RT_MAX) + cand.inf_max_rt = inf_max_rt; } 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) - odhcp6c_add_state(STATE_SERVER_CAND, &cand, sizeof(cand)); - - return -1; -} - - -static int dhcpv6_commit_advert(_unused uint32_t elapsed) -{ - size_t cand_len; - struct dhcpv6_server_cand *c = NULL, *cand = - odhcp6c_get_state(STATE_SERVER_CAND, &cand_len); - - bool retry = false; - for (size_t i = 0; i < cand_len / sizeof(*c); ++i) { - if (cand[i].has_noaddravail) - retry = true; // We want to try again + if ((!have_na && na_mode == IA_MODE_FORCE) || + (!have_pd && pd_mode == IA_MODE_FORCE)) { + /* + * RFC7083 states to process the SOL_MAX_RT and + * INF_MAX_RT options even if the DHCPv6 server + * did not propose any IA_NA and/or IA_PD + */ + dhcpv6_retx[DHCPV6_MSG_SOLICIT].max_timeo = cand.sol_max_rt; + dhcpv6_retx[DHCPV6_MSG_INFO_REQ].max_timeo = cand.inf_max_rt; + return -1; + } - if (!c || c->preference < cand[i].preference) - c = &cand[i]; + if (na_mode != IA_MODE_NONE && !have_na) { + cand.has_noaddravail = true; + cand.preference -= 1000; } - if (retry && na_mode == IA_MODE_TRY) { - // We give it a second try without the IA_NA - na_mode = IA_MODE_NONE; - return dhcpv6_request(DHCPV6_MSG_SOLICIT); + if (pd_mode != IA_MODE_NONE) { + if (have_pd) + cand.preference += 2000 + (128 - have_pd); + else + cand.preference -= 2000; } - if (c) { - uint16_t hdr[2] = {htons(DHCPV6_OPT_SERVERID), - htons(c->duid_len)}; - 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; + 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); + dhcpv6_add_server_cand(&cand); } - odhcp6c_clear_state(STATE_SERVER_CAND); + return (rc > 1 || (pref == 255 && cand.preference > 0)) ? 1 : -1; +} - if (!c) - return -1; - else if (request_prefix || na_mode != IA_MODE_NONE) - return DHCPV6_STATEFUL; - else - return DHCPV6_STATELESS; + +static int dhcpv6_commit_advert(void) +{ + return dhcpv6_promote_server_cand(); } -static int dhcpv6_handle_rebind_reply(enum dhcpv6_msg orig, - const void *opt, const void *end, uint32_t elapsed) +static int dhcpv6_handle_rebind_reply(enum dhcpv6_msg orig, const int rc, + const void *opt, const void *end) { - dhcpv6_handle_advert(orig, opt, end, elapsed); - if (dhcpv6_commit_advert(elapsed) < 0) + dhcpv6_handle_advert(orig, rc, opt, end); + if (dhcpv6_commit_advert() < 0) return -1; - return dhcpv6_handle_reply(orig, opt, end, elapsed); + return dhcpv6_handle_reply(orig, rc, 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, _unused const int rc, + const void *opt, const void *end) { - uint16_t otype, olen; uint8_t *odata; - bool have_update = false; + uint16_t otype, olen; + uint32_t refresh = UINT32_MAX; + int ret = 1; + bool handled_status_codes[_DHCPV6_Status_Max] = { false, }; + + odhcp6c_expire(); - t1 = t2 = t3 = 86400; + if (orig == DHCPV6_MSG_UNKNOWN) { + static time_t last_update = 0; + time_t now = odhcp6c_get_milli_time() / 1000; - size_t ia_na_len, dns_len, search_len, sntp_ip_len, sntp_dns_len; - size_t sip_ip_len, sip_fqdn_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); - odhcp6c_get_state(STATE_SIP_IP, &sip_ip_len); - odhcp6c_get_state(STATE_SIP_FQDN, &sip_fqdn_len); + uint32_t elapsed = (last_update > 0) ? now - last_update : 0; + last_update = now; - // 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); + t1 -= elapsed; + t2 -= elapsed; + t3 -= elapsed; - uint32_t pref = ntohl(p->preferred); - p->preferred = (pref < elapsed) ? 0 : htonl(pref - elapsed); + if (t1 < 0) + t1 = 0; + + if (t2 < 0) + t2 = 0; + + if (t3 < 0) + t3 = 0; } - // 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 && !odhcp6c_is_bound()) { + // 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 @@ -611,47 +847,51 @@ 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); - // Test ID and T1-T2 validity - if (ia_hdr->iaid != 1 || l_t2 < l_t1) + // Test ID + if (ia_hdr->iaid != 1) continue; + uint16_t code = DHCPV6_Success; uint16_t stype, slen; uint8_t *sdata; - // Test status and bail if error + // Get and handle status code dhcpv6_for_each_option(&ia_hdr[1], odata + olen, - stype, slen, sdata) - if (stype == DHCPV6_OPT_STATUS && slen >= 2 && - (sdata[0] || sdata[1])) - continue; + stype, slen, sdata) { + if (stype == DHCPV6_OPT_STATUS && slen >= 2) { + uint8_t *mdata = (slen > 2) ? &sdata[2] : NULL; + uint16_t mlen = (slen > 2) ? slen - 2 : 0; - // Update times - if (l_t1 > 0 && t1 > l_t1) - t1 = l_t1; + code = ((int)sdata[0]) << 8 | ((int)sdata[1]); - if (l_t2 > 0 && t2 > l_t2) - t2 = l_t2; + if (code == DHCPV6_Success) + continue; - // 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; + dhcpv6_handle_ia_status_code(orig, ia_hdr, + code, mdata, mlen, handled_status_codes, &ret); - time_t n = dhcpv6_parse_ia(&ia_hdr[1], odata + olen); - if (n < t1) - t1 = n; + if (ret > 0) + return ret; + break; + } + } - if (n < t2) - t2 = n; + if (code != DHCPV6_Success) + continue; - if (n < t3) - t3 = n; + dhcpv6_parse_ia(ia_hdr, odata + olen + sizeof(*ia_hdr)); + } else if (otype == DHCPV6_OPT_UNICAST && olen == sizeof(server_addr)) { + server_addr = *(struct in6_addr *)odata; + } else if (otype == DHCPV6_OPT_STATUS && olen >= 2) { + uint8_t *mdata = (olen > 2) ? &odata[2] : NULL; + uint16_t mlen = (olen > 2) ? olen - 2 : 0; + uint16_t code = ((int)odata[0]) << 8 | ((int)odata[1]); - } else if (otype == DHCPV6_OPT_DNS_SERVERS) { - if (olen == 16) + dhcpv6_handle_status_code(orig, code, mdata, mlen, &ret); + } + else if (otype == DHCPV6_OPT_DNS_SERVERS) { + 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); @@ -675,144 +915,428 @@ static int dhcpv6_handle_reply(_unused enum dhcpv6_msg orig, } 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_CLIENTID && + refresh = ntohl(*((uint32_t*)odata)); + } 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_SOL_MAX_RT && olen == 4) { + uint32_t sol_max_rt = ntohl(*((uint32_t *)odata)); + if (sol_max_rt >= DHCPV6_SOL_MAX_RT_MIN && + sol_max_rt <= DHCPV6_SOL_MAX_RT_MAX) + dhcpv6_retx[DHCPV6_MSG_SOLICIT].max_timeo = sol_max_rt; + } else if (otype == DHCPV6_OPT_INF_MAX_RT && olen == 4) { + uint32_t inf_max_rt = ntohl(*((uint32_t *)odata)); + if (inf_max_rt >= DHCPV6_INF_MAX_RT_MIN && + inf_max_rt <= DHCPV6_INF_MAX_RT_MAX) + dhcpv6_retx[DHCPV6_MSG_INFO_REQ].max_timeo = inf_max_rt; + }else if (otype != DHCPV6_OPT_CLIENTID && otype != DHCPV6_OPT_SERVERID) { odhcp6c_add_state(STATE_CUSTOM_OPTS, &odata[-4], olen + 4); } } - 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); - have_update |= odhcp6c_commit_state(STATE_SIP_IP, sip_ip_len); - have_update |= odhcp6c_commit_state(STATE_SIP_FQDN, sip_fqdn_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 (orig != DHCPV6_MSG_INFO_REQ) { + // Update refresh timers if no fatal status code was received + if ((ret > 0) && dhcpv6_calc_refresh_timers()) { + switch (orig) { + case DHCPV6_MSG_RENEW: + // Send further renews if T1 is not set + if (!t1) + ret = -1; + break; + case DHCPV6_MSG_REBIND: + // Send further rebinds if T1 and T2 is not set + if (!t1 && !t2) + ret = -1; + break; + + case DHCPV6_MSG_REQUEST: + // All server candidates can be cleared if not yet bound + if (!odhcp6c_is_bound()) + dhcpv6_clear_all_server_cand(); + + default : + break; + } } } + else if (ret > 0) { + // All server candidates can be cleared if not yet bound + if (!odhcp6c_is_bound()) + dhcpv6_clear_all_server_cand(); - - // 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; - } + t1 = refresh; } - return have_update; + return ret; } -static time_t dhcpv6_parse_ia(void *opt, void *end) +static int dhcpv6_parse_ia(void *opt, void *end) { - uint32_t timeout = UINT32_MAX; // Minimum timeout - uint16_t otype, olen, stype, slen; - uint8_t *odata, *sdata; + struct dhcpv6_ia_hdr *ia_hdr = (struct dhcpv6_ia_hdr *)opt; + int parsed_ia = 0; + uint32_t t1, t2; + uint16_t otype, olen; + uint8_t *odata; + + t1 = ntohl(ia_hdr->t1); + t2 = ntohl(ia_hdr->t2); + + if (t1 > t2) + return 0; // Update address IA - dhcpv6_for_each_option(opt, end, otype, olen, odata) { + dhcpv6_for_each_option(&ia_hdr[1], end, otype, olen, odata) { + struct odhcp6c_entry entry = {IN6ADDR_ANY_INIT, 0, 0, + IN6ADDR_ANY_INIT, 0, 0, 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.t1 = (t1 ? t1 : (entry.preferred != UINT32_MAX ? 0.5 * entry.preferred : UINT32_MAX)); + entry.t2 = (t2 ? t2 : (entry.preferred != UINT32_MAX ? 0.8 * entry.preferred : UINT32_MAX)); + if (entry.t1 > entry.t2) + entry.t1 = entry.t2; + + 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); + parsed_ia++; + } - 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, + entry.t1 = (t1 ? t1 : (entry.preferred != UINT32_MAX ? 0.5 * entry.preferred : UINT32_MAX)); + entry.t2 = (t2 ? t2 : (entry.preferred != UINT32_MAX ? 0.8 * entry.preferred : UINT32_MAX)); + if (entry.t1 > entry.t2) + entry.t1 = entry.t2; + + entry.length = 128; + entry.target = addr->addr; + +#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 (!memcmp(sdata, odata, sizeof(local->addr))) - local = (void*)&sdata[-4]; + if (stype == DHCPV6_OPT_PREFIX_CLASS && slen == 2) + entry.class = sdata[0] << 8 | sdata[1]; +#endif + + odhcp6c_update_entry(STATE_IA_NA, &entry); + parsed_ia++; + } + } + return parsed_ia; +} - 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); - } +static int dhcpv6_calc_refresh_timers(void) +{ + struct odhcp6c_entry *e; + size_t ia_na_entries, ia_pd_entries, i; + int64_t l_t1 = UINT32_MAX, l_t2 = UINT32_MAX, l_t3 = 0; + e = odhcp6c_get_state(STATE_IA_NA, &ia_na_entries); + ia_na_entries /= sizeof(*e); + for (i = 0; i < ia_na_entries; i++) { + if (e[i].t1 < l_t1) + l_t1 = e[i].t1; - if (timeout > valid) - timeout = valid; + if (e[i].t2 < l_t2) + l_t2 = e[i].t2; - if (set_rtnetlink_addr(ifindex, &addr->addr, - pref, valid) == -EADDRNOTAVAIL) { - dhcpv6_request(DHCPV6_MSG_DECLINE); - raise(SIGUSR2); - } + if (e[i].valid > l_t3) + l_t3 = e[i].valid; + } + + e = odhcp6c_get_state(STATE_IA_PD, &ia_pd_entries); + ia_pd_entries /= sizeof(*e); + for (i = 0; i < ia_pd_entries; i++) { + if (e[i].t1 < l_t1) + l_t1 = e[i].t1; + + if (e[i].t2 < l_t2) + l_t2 = e[i].t2; + + if (e[i].valid > l_t3) + l_t3 = e[i].valid; + } + + if (ia_pd_entries || ia_na_entries) { + t1 = l_t1; + t2 = l_t2; + t3 = l_t3; + } + + return (int)(ia_pd_entries + ia_na_entries); +} + + +static void dhcpv6_log_status_code(const uint16_t code, const char *scope, + const void *status_msg, const int len) +{ + uint8_t buf[len + 3]; + + memset(buf, 0, sizeof(buf)); + if (len) { + buf[0] = '('; + memcpy(&buf[1], status_msg, len); + buf[len + 1] = ')'; + } + + syslog(LOG_WARNING, "Server returned %s status %i %s", + scope, code, buf); +} + + +static void dhcpv6_handle_status_code(const enum dhcpv6_msg orig, + const uint16_t code, const void *status_msg, const int len, + int *ret) +{ + dhcpv6_log_status_code(code, "message", status_msg, len); + + switch (code) { + case DHCPV6_UnspecFail: + // Generic failure + *ret = 0; + break; + + case DHCPV6_UseMulticast: + switch(orig) { + case DHCPV6_MSG_REQUEST: + case DHCPV6_MSG_RENEW: + case DHCPV6_MSG_RELEASE: + case DHCPV6_MSG_DECLINE: + // Message needs to be retransmitted according to RFC3315 chapter 18.1.8 + server_addr = in6addr_any; + *ret = 0; + break; + default: + break; + } + break; + + case DHCPV6_NoAddrsAvail: + case DHCPV6_NoPrefixAvail: + if (orig == DHCPV6_MSG_REQUEST) + *ret = 0; // Failure + break; + + default: + break; + } +} + + +static void dhcpv6_handle_ia_status_code(const enum dhcpv6_msg orig, + const struct dhcpv6_ia_hdr *ia_hdr, const uint16_t code, + const void *status_msg, const int len, + bool handled_status_codes[_DHCPV6_Status_Max], int *ret) +{ + dhcpv6_log_status_code(code, ia_hdr->type == DHCPV6_OPT_IA_NA ? + "IA_NA" : "IA_PD", status_msg, len); + + switch (code) { + case DHCPV6_NoBinding: + switch (orig) { + case DHCPV6_MSG_RENEW: + case DHCPV6_MSG_REBIND: + if ((*ret > 0) && !handled_status_codes[code]) + *ret = dhcpv6_request(DHCPV6_MSG_REQUEST); + break; + + default: + break; + } + break; + + case DHCPV6_NoAddrsAvail: + case DHCPV6_NoPrefixAvail: + switch (orig) { + case DHCPV6_MSG_REQUEST: + if (*ret != 0) + *ret = 0; + break; + default: + break; + } + break; + + case DHCPV6_NotOnLink: + // TODO handle not onlink in case of confirm + break; + + default: + break; + } +} + +static void dhcpv6_add_server_cand(const struct dhcpv6_server_cand *cand) +{ + size_t cand_len, i; + struct dhcpv6_server_cand *c = odhcp6c_get_state(STATE_SERVER_CAND, &cand_len); + + // Remove identical duid server candidate + for (i = 0; i < cand_len / sizeof(*c); ++i) { + if (cand->duid_len == c[i].duid_len && + !memcmp(cand->duid, c[i].duid, cand->duid_len)) { + free(c[i].ia_na); + free(c[i].ia_pd); + odhcp6c_remove_state(STATE_SERVER_CAND, i * sizeof(*c), sizeof(*c)); + break; } } - return timeout; + for (i = 0, c = odhcp6c_get_state(STATE_SERVER_CAND, &cand_len); + i < cand_len / sizeof(*c); ++i) { + if (c[i].preference < cand->preference) + break; + } + + odhcp6c_insert_state(STATE_SERVER_CAND, i * sizeof(*c), cand, sizeof(*cand)); +} + +static void dhcpv6_clear_all_server_cand(void) +{ + size_t cand_len, i; + struct dhcpv6_server_cand *c = odhcp6c_get_state(STATE_SERVER_CAND, &cand_len); + + // Server candidates need deep delete for IA_NA/IA_PD + for (i = 0; i < cand_len / sizeof(*c); ++i) { + if (c[i].ia_na) + free(c[i].ia_na); + if (c[i].ia_pd) + free(c[i].ia_pd); + } + odhcp6c_clear_state(STATE_SERVER_CAND); +} + +int dhcpv6_promote_server_cand(void) +{ + size_t cand_len; + struct dhcpv6_server_cand *cand = odhcp6c_get_state(STATE_SERVER_CAND, &cand_len); + uint16_t hdr[2]; + int ret = DHCPV6_STATELESS; + + // Clear lingering candidate state info + odhcp6c_clear_state(STATE_SERVER_ID); + odhcp6c_clear_state(STATE_IA_NA); + odhcp6c_clear_state(STATE_IA_PD); + + if (!cand_len) + return -1; + + if (cand->has_noaddravail && na_mode == IA_MODE_TRY) { + na_mode = IA_MODE_NONE; + + dhcpv6_retx[DHCPV6_MSG_SOLICIT].max_timeo = cand->sol_max_rt; + dhcpv6_retx[DHCPV6_MSG_INFO_REQ].max_timeo = cand->inf_max_rt; + + return dhcpv6_request(DHCPV6_MSG_SOLICIT); + } + + hdr[0] = htons(DHCPV6_OPT_SERVERID); + hdr[1] = htons(cand->duid_len); + odhcp6c_add_state(STATE_SERVER_ID, hdr, sizeof(hdr)); + odhcp6c_add_state(STATE_SERVER_ID, cand->duid, cand->duid_len); + accept_reconfig = cand->wants_reconfigure; + if (cand->ia_na_len) { + odhcp6c_add_state(STATE_IA_NA, cand->ia_na, cand->ia_na_len); + free(cand->ia_na); + if (na_mode != IA_MODE_NONE) + ret = DHCPV6_STATEFUL; + } + if (cand->ia_pd_len) { + odhcp6c_add_state(STATE_IA_PD, cand->ia_pd, cand->ia_pd_len); + free(cand->ia_pd); + if (request_prefix) + ret = DHCPV6_STATEFUL; + } + + dhcpv6_retx[DHCPV6_MSG_SOLICIT].max_timeo = cand->sol_max_rt; + dhcpv6_retx[DHCPV6_MSG_INFO_REQ].max_timeo = cand->inf_max_rt; + + odhcp6c_remove_state(STATE_SERVER_CAND, 0, sizeof(*cand)); + + return ret; }