X-Git-Url: https://git.decadent.org.uk/gitweb/?p=odhcp6c.git;a=blobdiff_plain;f=src%2Fdhcpv6.c;h=d212decaa614ea9413fa7d77670b6a0a9564c5b9;hp=785b57b03aedf1543dea2ff08a08594599873ceb;hb=0c764d13ba834d6be53c4312007584613dec3a1e;hpb=8e50917e51f7f21c53f9021063670065c8fa06d8

diff --git a/src/dhcpv6.c b/src/dhcpv6.c
index 785b57b..d212dec 100644
--- a/src/dhcpv6.c
+++ b/src/dhcpv6.c
@@ -58,20 +58,20 @@ 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, "<POLL>",
-			dhcpv6_handle_reconfigure, NULL},
-	[DHCPV6_MSG_SOLICIT] = {true, 1, 3600, "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, "<POLL>",
+ 			dhcpv6_handle_reconfigure, NULL},
+	[DHCPV6_MSG_SOLICIT] = {true, 1, 3600, 0, "SOLICIT",
+ 			dhcpv6_handle_advert, dhcpv6_commit_advert},
+	[DHCPV6_MSG_REQUEST] = {true, 1, 30, 10, "REQUEST",
+ 			dhcpv6_handle_reply, NULL},
+	[DHCPV6_MSG_RENEW] = {false, 10, 600, 0, "RENEW",
+ 			dhcpv6_handle_reply, NULL},
+	[DHCPV6_MSG_REBIND] = {false, 10, 600, 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, 120, 0, "INFOREQ",
+ 			dhcpv6_handle_reply, NULL},
 };
 
 
@@ -82,7 +82,7 @@ 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
@@ -90,9 +90,10 @@ 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;
+	dhcpv6_retx[DHCPV6_MSG_SOLICIT].max_timeo = sol_timeout;
 
 	sock = socket(AF_INET6, SOCK_DGRAM | SOCK_CLOEXEC, IPPROTO_UDP);
 
@@ -156,6 +157,8 @@ int init_dhcpv6(const char *ifname, int request_pd)
 	int val = 1;
 	setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY, &val, sizeof(val));
 	setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &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,
@@ -167,9 +170,10 @@ 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;
+	na_mode = na;
+	pd_mode = pd;
 }
 
 
@@ -247,9 +251,7 @@ static void dhcpv6_send(enum dhcpv6_msg type, uint8_t trid[3], uint32_t ecs)
 		.type = htons(DHCPV6_OPT_IA_PREFIX),
 		.len = htons(25), .prefix = request_prefix
 	};
-	if (request_prefix > 0 && ia_pd_len == 0 &&
-			(type == DHCPV6_MSG_SOLICIT ||
-			type == DHCPV6_MSG_REQUEST)) {
+	if (request_prefix > 0 && ia_pd_len == 0 && type == DHCPV6_MSG_SOLICIT) {
 		ia_pd = (uint8_t*)&pref;
 		ia_pd_len = sizeof(pref);
 	}
@@ -331,7 +333,7 @@ static void dhcpv6_send(enum dhcpv6_msg type, uint8_t trid[3], uint32_t ecs)
 	}
 
 	// Disable IAs if not used
-	if (type != DHCPV6_MSG_REQUEST && type != DHCPV6_MSG_SOLICIT) {
+	if (type != DHCPV6_MSG_SOLICIT) {
 		iov[5].iov_len = 0;
 		if (ia_na_len == 0)
 			iov[7].iov_len = 0;
@@ -360,7 +362,7 @@ static int64_t dhcpv6_rand_delay(int64_t time)
 
 int dhcpv6_request(enum dhcpv6_msg type)
 {
-	uint8_t buf[1536];
+	uint8_t buf[1536], rc = 0;
 	uint64_t timeout = UINT32_MAX;
 	struct dhcpv6_retx *retx = &dhcpv6_retx[type];
 
@@ -370,9 +372,7 @@ 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) ? t2 - t1 : 0;
@@ -382,7 +382,7 @@ int dhcpv6_request(enum dhcpv6_msg type)
 	if (timeout == 0)
 		return -1;
 
-	syslog(LOG_NOTICE, "Sending %s (timeout %us)", retx->name, (unsigned)timeout);
+	syslog(LOG_NOTICE, "Starting %s transaction (timeout %llus, max rc %d)", retx->name, timeout, retx->max_rc);
 
 	uint64_t start = odhcp6c_get_milli_time(), round_start = start, elapsed;
 
@@ -394,11 +394,19 @@ int dhcpv6_request(enum dhcpv6_msg type)
 	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);
 
-		if (rto >= retx->max_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);
+
+			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);
 
@@ -411,8 +419,11 @@ 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) {
+			syslog(LOG_NOTICE, "Send %s message (elapsed %llums, rc %d)", retx->name, elapsed, rc);
 			dhcpv6_send(type, trid, elapsed / 10);
+			rc++;
+		}
 
 		// Receive rounds
 		for (; len < 0 && round_start < round_end;
@@ -440,13 +451,13 @@ int dhcpv6_request(enum dhcpv6_msg type)
 				round_start = odhcp6c_get_milli_time();
 				elapsed = round_start - start;
 				syslog(LOG_NOTICE, "Got a valid reply after "
-						"%ums", (unsigned)elapsed);
+						"%llums", elapsed);
 
 				if (retx->handler_reply)
 					len = retx->handler_reply(
-							type, opt, opt_end);
+							type, rc, opt, opt_end);
 
-				if (round_end - round_start > 1000)
+				if (len > 0 && round_end - round_start > 1000)
 					round_end = 1000 + round_start;
 			}
 		}
@@ -454,7 +465,7 @@ int dhcpv6_request(enum dhcpv6_msg type)
 		// Allow
 		if (retx->handler_finish)
 			len = retx->handler_finish();
-	} while (len < 0 && elapsed / 1000 < timeout);
+	} while (len < 0 && ((elapsed / 1000 < timeout) && (!retx->max_rc || rc < retx->max_rc)));
 
 	return len;
 }
@@ -545,7 +556,7 @@ int dhcpv6_poll_reconfigure(void)
 }
 
 
-static int dhcpv6_handle_reconfigure(_unused enum dhcpv6_msg orig,
+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
@@ -557,18 +568,20 @@ static int dhcpv6_handle_reconfigure(_unused enum dhcpv6_msg orig,
 				odata[0] == DHCPV6_MSG_INFO_REQ))
 			msg = odata[0];
 
-	dhcpv6_handle_reply(DHCPV6_MSG_UNKNOWN, NULL, NULL);
+	dhcpv6_handle_reply(DHCPV6_MSG_UNKNOWN, rc, NULL, NULL);
 	return msg;
 }
 
 
 // Collect all advertised servers
-static int dhcpv6_handle_advert(enum dhcpv6_msg orig,
+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;
+	uint8_t *odata, pref = 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 &&
@@ -581,36 +594,66 @@ static int dhcpv6_handle_advert(enum dhcpv6_msg orig,
 		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
+				if (pd_mode == IA_MODE_FORCE)
+					return -1;
+				cand.preference -= 2000;
+				break;
+
+			case DHCPV6_NoAddrsAvail:
+				// Status code on global level
+				if (na_mode == IA_MODE_FORCE)
+					return -1;
+				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[0];
+			cand.preference = pref = 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 = (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 ((!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);
@@ -622,7 +665,7 @@ static int dhcpv6_handle_advert(enum dhcpv6_msg orig,
 		odhcp6c_clear_state(STATE_IA_PD);
 	}
 
-	return -1;
+	return (rc > 1 || (pref == 255 && cand.preference > 0)) ? 1 : -1;
 }
 
 
@@ -653,8 +696,10 @@ static int dhcpv6_commit_advert(void)
 		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);
+		if (c->ia_na_len)
+			odhcp6c_add_state(STATE_IA_NA, c->ia_na, c->ia_na_len);
+		if (c->ia_pd_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) {
@@ -665,27 +710,27 @@ static int dhcpv6_commit_advert(void)
 
 	if (!c)
 		return -1;
-	else if (request_prefix || na_mode != IA_MODE_NONE)
+	else if ((request_prefix && c->ia_pd_len) || (na_mode != IA_MODE_NONE && c->ia_na_len))
 		return DHCPV6_STATEFUL;
 	else
 		return DHCPV6_STATELESS;
 }
 
 
-static int dhcpv6_handle_rebind_reply(enum dhcpv6_msg orig,
+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);
+	dhcpv6_handle_advert(orig, rc, opt, end);
 	if (dhcpv6_commit_advert() < 0) {
-		dhcpv6_handle_reply(DHCPV6_MSG_UNKNOWN, NULL, NULL);
+		dhcpv6_handle_reply(DHCPV6_MSG_UNKNOWN, rc, NULL, NULL);
 		return -1;
 	}
 
-	return dhcpv6_handle_reply(orig, opt, end);
+	return dhcpv6_handle_reply(orig, rc, opt, end);
 }
 
 
-static int dhcpv6_handle_reply(enum dhcpv6_msg orig,
+static int dhcpv6_handle_reply(enum dhcpv6_msg orig, _unused const int rc,
 		const void *opt, const void *end)
 {
 	uint8_t *odata;
@@ -744,18 +789,21 @@ static int dhcpv6_handle_reply(enum dhcpv6_msg orig,
 			if (ia_hdr->iaid != 1 || l_t2 < l_t1)
 				continue;
 
-			bool error = false;
+			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]))
-					error = true;
-
-			if (error)
-				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);
 
@@ -821,6 +869,15 @@ static int dhcpv6_handle_reply(enum dhcpv6_msg orig,
 		}
 	}
 
+	if (t1 == UINT32_MAX)
+		t1 = 300;
+
+	if (t2 == UINT32_MAX)
+		t2 = 600;
+
+	if (t3 == UINT32_MAX)
+		t3 = 3600;
+
 	return true;
 }