X-Git-Url: http://git.sameswireless.fr/l2tpns.git/blobdiff_plain/97ad99cc23c5f0007de461afb200fd83c3d20481..b3335712110224f0a27e58320ebc6b4459d7ac34:/l2tpns.c?ds=sidebyside

diff --git a/l2tpns.c b/l2tpns.c
index 3099b97..1f47934 100644
--- a/l2tpns.c
+++ b/l2tpns.c
@@ -4,7 +4,7 @@
 // Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced
 // vim: sw=8 ts=8
 
-char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.80 2005/01/25 04:19:05 bodea Exp $";
+char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.90 2005/04/18 05:07:20 bodea Exp $";
 
 #include <arpa/inet.h>
 #include <assert.h>
@@ -68,11 +68,10 @@ static int rand_fd = -1;	// Random data source
 time_t basetime = 0;		// base clock
 char hostname[1000] = "";	// us.
 static int tunidx;		// ifr_ifindex of tun device
-static uint32_t sessionid = 0;	// session id for radius accounting
 static int syslog_log = 0;	// are we logging to syslog
 static FILE *log_stream = NULL;	// file handle for direct logging (i.e. direct into file, not via syslog).
 extern int cluster_sockfd;	// Intra-cluster communications socket.
-uint32_t last_id = 0;		// Last used PPP SID. Can I kill this?? -- mo
+uint32_t last_id = 0;		// Unique ID for radius accounting
 
 struct cli_session_actions *cli_session_actions = NULL;	// Pending session changes requested by CLI
 struct cli_tunnel_actions *cli_tunnel_actions = NULL;	// Pending tunnel changes required by CLI
@@ -106,7 +105,6 @@ config_descriptt config_values[] = {
 	CONFIG("l2tp_secret", l2tpsecret, STRING),
 	CONFIG("primary_dns", default_dns1, IPv4),
 	CONFIG("secondary_dns", default_dns2, IPv4),
-	CONFIG("save_state", save_state, BOOL),
 	CONFIG("primary_radius", radiusserver[0], IPv4),
 	CONFIG("secondary_radius", radiusserver[1], IPv4),
 	CONFIG("primary_radius_port", radiusport[0], SHORT),
@@ -179,8 +177,6 @@ static void sigalrm_handler(int sig);
 static void sigterm_handler(int sig);
 static void sigquit_handler(int sig);
 static void sigchild_handler(int sig);
-static void read_state(void);
-static void dump_state(void);
 static void build_chap_response(char *challenge, uint8_t id, uint16_t challenge_length, char **challenge_response);
 static void update_config(void);
 static void read_config_file(void);
@@ -190,7 +186,7 @@ static int remove_plugin(char *plugin_name);
 static void plugins_done(void);
 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen);
 static tunnelidt new_tunnel(void);
-static int unhide_avp(uint8_t *avp, tunnelidt t, sessionidt s, uint16_t length);
+static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len);
 
 // return internal time (10ths since process startup)
 static clockt now(void)
@@ -632,7 +628,7 @@ static int lookup_ipmap(in_addr_t ip)
 	return (int) (intptr_t) d[(size_t) *a];
 }
 
-int lookup_ipv6map(struct in6_addr ip)
+static int lookup_ipv6map(struct in6_addr ip)
 {
 	struct ipv6radix *curnode;
 	int i;
@@ -663,7 +659,7 @@ sessionidt sessionbyip(in_addr_t ip)
 	int s = lookup_ipmap(ip);
 	CSTAT(sessionbyip);
 
-	if (s > 0 && s < MAXSESSION && session[s].tunnel)
+	if (s > 0 && s < MAXSESSION && session[s].opened)
 		return (sessionidt) s;
 
 	return 0;
@@ -682,7 +678,7 @@ sessionidt sessionbyipv6(struct in6_addr ip)
 		s = lookup_ipv6map(ip);
 	}
 
-	if (s > 0 && s < MAXSESSION && session[s].tunnel)
+	if (s > 0 && s < MAXSESSION && session[s].opened)
 		return s;
 
 	return 0;
@@ -818,8 +814,11 @@ sessionidt sessionbyuser(char *username)
 	int s;
 	CSTAT(sessionbyuser);
 
-	for (s = 1; s < MAXSESSION ; ++s)
+	for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
 	{
+		if (!session[s].opened)
+			continue;
+
 		if (session[s].walled_garden)
 			continue;		// Skip walled garden users.
 
@@ -861,17 +860,16 @@ void send_garp(in_addr_t ip)
 	sendarp(ifr.ifr_ifindex, mac, ip);
 }
 
-// Find session by username, 0 for not found
 static sessiont *sessiontbysessionidt(sessionidt s)
 {
-	if (!s || s > MAXSESSION) return NULL;
+	if (!s || s >= MAXSESSION) return NULL;
 	return &session[s];
 }
 
 static sessionidt sessionidtbysessiont(sessiont *s)
 {
 	sessionidt val = s-session;
-	if (s < session || val > MAXSESSION) return 0;
+	if (s < session || val >= MAXSESSION) return 0;
 	return val;
 }
 
@@ -1086,7 +1084,7 @@ static void processipout(uint8_t * buf, int len)
 
 // process outgoing (to tunnel) IPv6
 //
-void processipv6out(uint8_t * buf, int len)
+static void processipv6out(uint8_t * buf, int len)
 {
 	sessionidt s;
 	sessiont *sp;
@@ -1265,7 +1263,7 @@ static void control32(controlt * c, uint16_t avp, uint32_t val, uint8_t m)
 	c->length += 10;
 }
 
-// add an AVP (32 bit)
+// add an AVP (string)
 static void controls(controlt * c, uint16_t avp, char *val, uint8_t m)
 {
 	uint16_t l = ((m ? 0x8000 : 0) + strlen(val) + 6);
@@ -1360,7 +1358,7 @@ static void controladd(controlt * c, tunnelidt t, sessionidt s)
 //
 void throttle_session(sessionidt s, int rate_in, int rate_out)
 {
-	if (!session[s].tunnel)
+	if (!session[s].opened)
 		return; // No-one home.
 
 	if (!*session[s].user)
@@ -1396,9 +1394,9 @@ void throttle_session(sessionidt s, int rate_in, int rate_out)
 }
 
 // add/remove filters from session (-1 = no change)
-void filter_session(sessionidt s, int filter_in, int filter_out)
+static void filter_session(sessionidt s, int filter_in, int filter_out)
 {
-	if (!session[s].tunnel)
+	if (!session[s].opened)
 		return; // No-one home.
 
 	if (!*session[s].user)
@@ -1434,16 +1432,16 @@ void filter_session(sessionidt s, int filter_in, int filter_out)
 }
 
 // start tidy shutdown of session
-void sessionshutdown(sessionidt s, char *reason)
+void sessionshutdown(sessionidt s, char *reason, int result, int error)
 {
 	int walled_garden = session[s].walled_garden;
 
 
 	CSTAT(sessionshutdown);
 
-	if (!session[s].tunnel)
+	if (!session[s].opened)
 	{
-		LOG(3, s, session[s].tunnel, "Called sessionshutdown on a session with no tunnel.\n");
+		LOG(3, s, session[s].tunnel, "Called sessionshutdown on an unopened session.\n");
 		return;                   // not a live session
 	}
 
@@ -1454,7 +1452,7 @@ void sessionshutdown(sessionidt s, char *reason)
 		run_plugins(PLUGIN_KILL_SESSION, &data);
 	}
 
-	if (session[s].opened && !walled_garden && !session[s].die)
+	if (session[s].ip && !walled_garden && !session[s].die)
 	{
 		// RADIUS Stop message
 		uint16_t r = session[s].radius;
@@ -1509,15 +1507,25 @@ void sessionshutdown(sessionidt s, char *reason)
 	if (session[s].throttle_in || session[s].throttle_out) // Unthrottle if throttled.
 		throttle_session(s, 0, 0);
 
+	if (result)
 	{                            // Send CDN
 		controlt *c = controlnew(14); // sending CDN
-		control16(c, 1, 3, 1);    // result code (admin reasons - TBA make error, general error, add message
+		if (error)
+		{
+			char buf[4];
+			*(uint16_t *) buf     = htons(result);
+			*(uint16_t *) (buf+2) = htons(error);
+			controlb(c, 1, buf, 4, 1);
+		}
+		else
+			control16(c, 1, result, 1);
+
 		control16(c, 14, s, 1);   // assigned session (our end)
 		controladd(c, session[s].tunnel, s); // send the message
 	}
 
 	if (!session[s].die)
-		session[s].die = now() + 150; // Clean up in 15 seconds
+		session[s].die = TIME + 150; // Clean up in 15 seconds
 
 	// update filter refcounts
 	if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
@@ -1547,7 +1555,7 @@ void sendipcp(tunnelidt t, sessionidt s)
 	if (radius[r].try > 10)
 	{
 		radiusclear(r, s);	// Clear radius session.
-		sessionshutdown(s, "No reply on IPCP");
+		sessionshutdown(s, "No reply on IPCP", 3, 0);
 		return;
 	}
 
@@ -1592,13 +1600,22 @@ void sendipcp(tunnelidt t, sessionidt s)
 }
 
 // kill a session now
-static void sessionkill(sessionidt s, char *reason)
+void sessionkill(sessionidt s, char *reason)
 {
 
 	CSTAT(sessionkill);
 
-	session[s].die = now();
-	sessionshutdown(s, reason);  // close radius/routes, etc.
+	if (!session[s].opened) // not alive
+		return;
+
+	if (session[s].next)
+	{
+		LOG(0, s, session[s].tunnel, "Tried to kill a session with next pointer set (%d)\n", session[s].next);
+		return;
+	}
+
+	session[s].die = TIME;
+	sessionshutdown(s, reason, 3, 0);  // close radius/routes, etc.
 	if (session[s].radius)
 		radiusclear(session[s].radius, s); // cant send clean accounting data, session is killed
 
@@ -1639,19 +1656,19 @@ static void tunnelkill(tunnelidt t, char *reason)
 		controlfree = c;
 	}
 	// kill sessions
-	for (s = 1; s < MAXSESSION; s++)
+	for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
 		if (session[s].tunnel == t)
 			sessionkill(s, reason);
 
 	// free tunnel
 	tunnelclear(t);
 	LOG(1, 0, t, "Kill tunnel %d: %s\n", t, reason);
-	cli_tunnel_actions[s].action = 0;
+	cli_tunnel_actions[t].action = 0;
 	cluster_send_tunnel(t);
 }
 
 // shut down a tunnel cleanly
-static void tunnelshutdown(tunnelidt t, char *reason)
+static void tunnelshutdown(tunnelidt t, char *reason, int result, int error, char *msg)
 {
 	sessionidt s;
 
@@ -1666,19 +1683,40 @@ static void tunnelshutdown(tunnelidt t, char *reason)
 	LOG(1, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
 
 	// close session
-	for (s = 1; s < MAXSESSION; s++)
+	for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
 		if (session[s].tunnel == t)
-			sessionshutdown(s, reason);
+			sessionshutdown(s, reason, 3, 0);
 
 	tunnel[t].state = TUNNELDIE;
-	tunnel[t].die = now() + 700; // Clean up in 70 seconds
+	tunnel[t].die = TIME + 700; // Clean up in 70 seconds
 	cluster_send_tunnel(t);
 	// TBA - should we wait for sessions to stop?
-	{                            // Send StopCCN
-		controlt *c = controlnew(4); // sending StopCCN
-		control16(c, 1, 1, 1);    // result code (admin reasons - TBA make error, general error, add message)
-		control16(c, 9, t, 1);    // assigned tunnel (our end)
-		controladd(c, t, 0);      // send the message
+	if (result) 
+	{
+		controlt *c = controlnew(4);	// sending StopCCN
+		if (error)
+		{
+			char buf[64];
+			int l = 4;
+			*(uint16_t *) buf     = htons(result);
+			*(uint16_t *) (buf+2) = htons(error);
+			if (msg)
+			{
+				int m = strlen(msg);
+				if (m + 4 > sizeof(buf))
+				    m = sizeof(buf) - 4;
+
+				memcpy(buf+4, msg, m);
+				l += m;
+			}
+
+			controlb(c, 1, buf, l, 1);
+		}
+		else
+			control16(c, 1, result, 1);
+
+		control16(c, 9, t, 1);		// assigned tunnel (our end)
+		controladd(c, t, 0);		// send the message
 	}
 }
 
@@ -1753,7 +1791,7 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
 	{                          // control
 		uint16_t message = 0xFFFF;	// message type
 		uint8_t fatal = 0;
-		uint8_t mandatorymessage = 0;
+		uint8_t mandatory = 0;
 		uint8_t chap = 0;		// if CHAP being used
 		uint16_t asession = 0;		// assigned session
 		uint32_t amagic = 0;		// magic number
@@ -1769,7 +1807,10 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
 			return;
 		}
 
-		if ((*buf & 0xCA) != 0xC8)
+		// control messages must have bits 0x80|0x40|0x08
+		// (type, length and sequence) set, and bits 0x02|0x01
+		// (offset and priority) clear
+		if ((*buf & 0xCB) != 0xC8)
 		{
 			LOG(1, s, t, "Bad control header %02X\n", *buf);
 			STAT(tunnel_rx_errors);
@@ -1879,71 +1920,111 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
 		}
 		if (l)
 		{                     // if not a null message
+			int result = 0;
+			int error = 0;
+			char *msg = 0;
+
 			// process AVPs
-			while (l && !(fatal & 0x80))
+			while (l && !(fatal & 0x80)) // 0x80 = mandatory AVP
 			{
 				uint16_t n = (ntohs(*(uint16_t *) p) & 0x3FF);
 				uint8_t *b = p;
 				uint8_t flags = *p;
 				uint16_t mtype;
-				p += n;       // next
-				if (l < n)
+				if (n > l)
 				{
 					LOG(1, s, t, "Invalid length in AVP\n");
 					STAT(tunnel_rx_errors);
-					fatal = flags;
 					return;
 				}
+				p += n;       // next
 				l -= n;
+				if (flags & 0x3C) // reserved bits, should be clear
+				{
+					LOG(1, s, t, "Unrecognised AVP flags %02X\n", *b);
+					fatal = flags;
+					result = 2; // general error
+					error = 3; // reserved field non-zero
+					msg = 0;
+					continue; // next
+				}
+				b += 2;
+				if (*(uint16_t *) (b))
+				{
+					LOG(2, s, t, "Unknown AVP vendor %d\n", ntohs(*(uint16_t *) (b)));
+					fatal = flags;
+					result = 2; // general error
+					error = 6; // generic vendor-specific error
+					msg = "unsupported vendor-specific";
+					continue; // next
+				}
+				b += 2;
+				mtype = ntohs(*(uint16_t *) (b));
+				b += 2;
+				n -= 6;
+
 				if (flags & 0x40)
 				{
+					uint16_t orig_len;
+
 					// handle hidden AVPs
 					if (!*config->l2tpsecret)
 					{
 						LOG(1, s, t, "Hidden AVP requested, but no L2TP secret.\n");
 						fatal = flags;
+						result = 2; // general error
+						error = 6; // generic vendor-specific error
+						msg = "secret not specified";
 						continue;
 					}
 					if (!session[s].random_vector_length)
 					{
 						LOG(1, s, t, "Hidden AVP requested, but no random vector.\n");
 						fatal = flags;
+						result = 2; // general error
+						error = 6; // generic
+						msg = "no random vector";
 						continue;
 					}
+					if (n < 8)
+					{
+						LOG(2, s, t, "Short hidden AVP.\n");
+						fatal = flags;
+						result = 2; // general error
+						error = 2; // length is wrong
+						msg = 0;
+						continue;
+					}
+
 					LOG(4, s, t, "Hidden AVP\n");
+
 					// Unhide the AVP
-					n = unhide_avp(b, t, s, n);
-					if (n == 0)
+					unhide_value(b, n, mtype, session[s].random_vector, session[s].random_vector_length);
+
+					orig_len = ntohs(*(uint16_t *) b);
+					if (orig_len > n + 2)
 					{
+						LOG(1, s, t, "Original length %d too long in hidden AVP of length %d; wrong secret?\n",
+						    orig_len, n);
+
 						fatal = flags;
+						result = 2; // general error
+						error = 2; // length is wrong
+						msg = 0;
 						continue;
 					}
+
+					b += 2;
+					n = orig_len;
 				}
-				if (*b & 0x3C)
-				{
-					LOG(1, s, t, "Unrecognised AVP flags %02X\n", *b);
-					fatal = flags;
-					continue; // next
-				}
-				b += 2;
-				if (*(uint16_t *) (b))
-				{
-					LOG(2, s, t, "Unknown AVP vendor %d\n", ntohs(*(uint16_t *) (b)));
-					fatal = flags;
-					continue; // next
-				}
-				b += 2;
-				mtype = ntohs(*(uint16_t *) (b));
-				b += 2;
-				n -= 6;
 
 				LOG(4, s, t, "   AVP %d (%s) len %d\n", mtype, avp_name(mtype), n);
 				switch (mtype)
 				{
 				case 0:     // message type
 					message = ntohs(*(uint16_t *) b);
+					mandatory = flags & 0x80;
 					LOG(4, s, t, "   Message type = %d (%s)\n", *b, l2tp_message_type(message));
-					mandatorymessage = flags;
 					break;
 				case 1:     // result code
 					{
@@ -1978,6 +2059,9 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
 						{   // allow 0.0 and 1.0
 							LOG(1, s, t, "   Bad protocol version %04X\n", version);
 							fatal = flags;
+							result = 5; // unspported protocol version
+							error = 0x0100; // supported version
+							msg = 0;
 							continue; // next
 						}
 					}
@@ -2154,14 +2238,20 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
 					session[s].random_vector_length = n;
 					break;
 				default:
-					LOG(2, s, t, "   Unknown AVP type %d\n", mtype);
-					fatal = flags;
-					continue; // next
+					{
+						static char e[] = "unknown AVP 0xXXXX";
+						LOG(2, s, t, "   Unknown AVP type %d\n", mtype);
+						fatal = flags;
+						result = 2; // general error
+						error = 8; // unknown mandatory AVP
+						sprintf((msg = e) + 14, "%04x", mtype);
+						continue; // next
+					}
 				}
 			}
 			// process message
 			if (fatal & 0x80)
-				tunnelshutdown(t, "Unknown Mandatory AVP");
+				tunnelshutdown(t, "Invalid mandatory AVP", result, error, msg);
 			else
 				switch (message)
 				{
@@ -2186,8 +2276,7 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
 					break;
 				case 4:       // StopCCN
 					controlnull(t); // ack
-					tunnelshutdown(t, "Stopped"); // Shut down cleanly
-					tunnelkill(t, "Stopped"); // Immediately force everything dead
+					tunnelshutdown(t, "Stopped", 0, 0, 0); // Shut down cleanly
 					break;
 				case 6:       // HELLO
 					controlnull(t); // simply ACK
@@ -2205,7 +2294,8 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
 					if (!sessionfree)
 					{
 						STAT(session_overflow);
-						tunnelshutdown(t, "No free sessions");
+						LOG(1, 0, t, "No free sessions");
+						return;
 					}
 					else
 					{
@@ -2228,8 +2318,7 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
 						}
 
 						c = controlnew(11); // sending ICRP
-						session[s].id = sessionid++;
-						session[s].opened = time(NULL);
+						session[s].opened = time_now;
 						session[s].tunnel = t;
 						session[s].far = asession;
 						session[s].last_packet = time_now;
@@ -2260,15 +2349,15 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
 					break;
 				case 14:      // CDN
 					controlnull(t); // ack
-					sessionshutdown(s, "Closed (Received CDN)");
+					sessionshutdown(s, "Closed (Received CDN)", 0, 0);
 					break;
 				case 0xFFFF:
 					LOG(1, s, t, "Missing message type\n");
 					break;
 				default:
 					STAT(tunnel_rx_errors);
-					if (mandatorymessage & 0x80)
-						tunnelshutdown(t, "Unknown message");
+					if (mandatory)
+						tunnelshutdown(t, "Unknown message type", 2, 6, "unknown message type");
 					else
 						LOG(1, s, t, "Unknown message type %d\n", message);
 					break;
@@ -2309,7 +2398,7 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
 			l -= 2;
 		}
 
-		if (s && !session[s].tunnel)	// Is something wrong??
+		if (s && !session[s].opened)	// Is something wrong??
 		{
 			if (!config->cluster_iam_master)
 			{
@@ -2319,9 +2408,7 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
 			}
 
 
-			LOG(1, s, t, "UDP packet contains session %d but no session[%d].tunnel "
-				     "exists (LAC said tunnel = %d).  Dropping packet.\n", s, s, t);
-
+			LOG(1, s, t, "UDP packet contains session which is not opened.  Dropping packet.\n");
 			STAT(tunnel_rx_errors);
 			return;
 		}
@@ -2515,7 +2602,7 @@ static int regular_cleanups(void)
 			if (a & CLI_TUN_KILL)
 			{
 				LOG(2, 0, t, "Dropping tunnel by CLI\n");
-				tunnelshutdown(t, "Requested by administrator");
+				tunnelshutdown(t, "Requested by administrator", 1, 0, 0);
 			}
 		}
 
@@ -2528,7 +2615,7 @@ static int regular_cleanups(void)
 		if (s > config->cluster_highest_sessionid)
 			s = 1;
 
-		if (!session[s].tunnel)	// Session isn't in use
+		if (!session[s].opened)	// Session isn't in use
 			continue;
 
 		if (!session[s].die && session[s].ip && !(session[s].flags & SF_IPCP_ACKED))
@@ -2549,13 +2636,13 @@ static int regular_cleanups(void)
 		// Drop sessions who have not responded within IDLE_TIMEOUT seconds
 		if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
 		{
-			sessionshutdown(s, "No response to LCP ECHO requests");
+			sessionshutdown(s, "No response to LCP ECHO requests", 3, 0);
 			STAT(session_timeout);
 			if (++count >= MAX_ACTIONS) break;
 			continue;
 		}
 
-		// No data in IDLE_TIMEOUT seconds, send LCP ECHO
+		// No data in ECHO_TIMEOUT seconds, send LCP ECHO
 		if (session[s].user[0] && (time_now - session[s].last_packet >= ECHO_TIMEOUT))
 		{
 			uint8_t b[MAXCONTROL] = {0};
@@ -2583,7 +2670,7 @@ static int regular_cleanups(void)
 			if (a & CLI_SESS_KILL)
 			{
 				LOG(2, s, session[s].tunnel, "Dropping session by CLI\n");
-				sessionshutdown(s, "Requested by administrator");
+				sessionshutdown(s, "Requested by administrator", 3, 0);
 				a = 0; // dead, no need to check for other actions
 			}
 
@@ -3137,7 +3224,7 @@ static void initdata(int optdebug, char *optconfig)
 	memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
 
 		// Put all the sessions on the free list marked as undefined.
-	for (i = 1; i < MAXSESSION - 1; i++)
+	for (i = 1; i < MAXSESSION; i++)
 	{
 		session[i].next = i + 1;
 		session[i].tunnel = T_UNDEF;	// mark it as not filled in.
@@ -3146,7 +3233,7 @@ static void initdata(int optdebug, char *optconfig)
 	sessionfree = 1;
 
 		// Mark all the tunnels as undefined (waiting to be filled in by a download).
-	for (i = 1; i < MAXTUNNEL- 1; i++)
+	for (i = 1; i < MAXTUNNEL; i++)
 		tunnel[i].state = TUNNELUNDEF;	// mark it as not filled in.
 
 	if (!*hostname)
@@ -3272,8 +3359,9 @@ void rebuild_address_pool(void)
 	for (i = 0; i < MAXSESSION; ++i)
 	{
 		int ipid;
-		if (!session[i].ip || !session[i].tunnel)
+		if (!(session[i].opened && session[i].ip))
 			continue;
+
 		ipid = - lookup_ipmap(htonl(session[i].ip));
 
 		if (session[i].ip_pool_index < 0)
@@ -3637,8 +3725,6 @@ int main(int argc, char *argv[])
 	initrad();
 	initippool();
 
-	read_state();
-
 	signal(SIGHUP, sighup_handler);
 	signal(SIGTERM, sigterm_handler);
 	signal(SIGINT, sigterm_handler);
@@ -3730,9 +3816,6 @@ static void sigalrm_handler(int sig)
 static void sigterm_handler(int sig)
 {
 	LOG(1, 0, 0, "Shutting down cleanly\n");
-	if (config->save_state)
-		dump_state();
-
 	main_quit++;
 }
 
@@ -3752,7 +3835,7 @@ static void sigquit_handler(int sig)
 		for (i = 1; i < MAXTUNNEL; i++)
 		{
 			if (tunnel[i].ip || tunnel[i].state)
-				tunnelshutdown(i, "L2TPNS Closing");
+				tunnelshutdown(i, "L2TPNS Closing", 6, 0, 0);
 		}
 	}
 
@@ -3765,182 +3848,6 @@ static void sigchild_handler(int sig)
 	    ;
 }
 
-static void read_state()
-{
-	struct stat sb;
-	int i;
-	ippoolt itmp;
-	FILE *f;
-	char magic[sizeof(DUMP_MAGIC) - 1];
-	uint32_t buf[2];
-
-	if (!config->save_state)
-	{
-		unlink(STATEFILE);
-		return ;
-	}
-
-	if (stat(STATEFILE, &sb) < 0)
-	{
-		unlink(STATEFILE);
-		return ;
-	}
-
-	if (sb.st_mtime < (time(NULL) - 60))
-	{
-		LOG(0, 0, 0, "State file is too old to read, ignoring\n");
-		unlink(STATEFILE);
-		return ;
-	}
-
-	f = fopen(STATEFILE, "r");
-	unlink(STATEFILE);
-
-	if (!f)
-	{
-		LOG(0, 0, 0, "Can't read state file: %s\n", strerror(errno));
-		exit(1);
-	}
-
-	if (fread(magic, sizeof(magic), 1, f) != 1 || strncmp(magic, DUMP_MAGIC, sizeof(magic)))
-	{
-		LOG(0, 0, 0, "Bad state file magic\n");
-		exit(1);
-	}
-
-	LOG(1, 0, 0, "Reading state information\n");
-	if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] > MAXIPPOOL || buf[1] != sizeof(ippoolt))
-	{
-		LOG(0, 0, 0, "Error/mismatch reading ip pool header from state file\n");
-		exit(1);
-	}
-
-	if (buf[0] > ip_pool_size)
-	{
-		LOG(0, 0, 0, "ip pool has shrunk!  state = %d, current = %d\n", buf[0], ip_pool_size);
-		exit(1);
-	}
-
-	LOG(2, 0, 0, "Loading %u ip addresses\n", buf[0]);
-	for (i = 0; i < buf[0]; i++)
-	{
-		if (fread(&itmp, sizeof(itmp), 1, f) != 1)
-		{
-			LOG(0, 0, 0, "Error reading ip %d from state file: %s\n", i, strerror(errno));
-			exit(1);
-		}
-
-		if (itmp.address != ip_address_pool[i].address)
-		{
-			LOG(0, 0, 0, "Mismatched ip %d from state file: pool may only be extended\n", i);
-			exit(1);
-		}
-
-		memcpy(&ip_address_pool[i], &itmp, sizeof(itmp));
-	}
-
-	if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] != MAXTUNNEL || buf[1] != sizeof(tunnelt))
-	{
-		LOG(0, 0, 0, "Error/mismatch reading tunnel header from state file\n");
-		exit(1);
-	}
-
-	LOG(2, 0, 0, "Loading %u tunnels\n", MAXTUNNEL);
-	if (fread(tunnel, sizeof(tunnelt), MAXTUNNEL, f) != MAXTUNNEL)
-	{
-		LOG(0, 0, 0, "Error reading tunnel data from state file\n");
-		exit(1);
-	}
-
-	for (i = 0; i < MAXTUNNEL; i++)
-	{
-		tunnel[i].controlc = 0;
-		tunnel[i].controls = NULL;
-		tunnel[i].controle = NULL;
-		if (*tunnel[i].hostname)
-			LOG(3, 0, 0, "Created tunnel for %s\n", tunnel[i].hostname);
-	}
-
-	if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] != MAXSESSION || buf[1] != sizeof(sessiont))
-	{
-		LOG(0, 0, 0, "Error/mismatch reading session header from state file\n");
-		exit(1);
-	}
-
-	LOG(2, 0, 0, "Loading %u sessions\n", MAXSESSION);
-	if (fread(session, sizeof(sessiont), MAXSESSION, f) != MAXSESSION)
-	{
-		LOG(0, 0, 0, "Error reading session data from state file\n");
-		exit(1);
-	}
-
-	for (i = 0; i < MAXSESSION; i++)
-	{
-		session[i].tbf_in = 0;
-		session[i].tbf_out = 0;
-		if (session[i].opened)
-		{
-			LOG(2, i, 0, "Loaded active session for user %s\n", session[i].user);
-			if (session[i].ip)
-				sessionsetup(session[i].tunnel, i);
-		}
-	}
-
-	fclose(f);
-	LOG(0, 0, 0, "Loaded saved state information\n");
-}
-
-static void dump_state()
-{
-	FILE *f;
-	uint32_t buf[2];
-
-	if (!config->save_state)
-		return;
-
-	do
-	{
-		if (!(f = fopen(STATEFILE, "w")))
-			break;
-
-		LOG(1, 0, 0, "Dumping state information\n");
-
-		if (fwrite(DUMP_MAGIC, sizeof(DUMP_MAGIC) - 1, 1, f) != 1)
-			break;
-
-		LOG(2, 0, 0, "Dumping %u ip addresses\n", ip_pool_size);
-		buf[0] = ip_pool_size;
-		buf[1] = sizeof(ippoolt);
-		if (fwrite(buf, sizeof(buf), 1, f) != 1)
-			break;
-		if (fwrite(ip_address_pool, sizeof(ippoolt), ip_pool_size, f) != ip_pool_size)
-			break;
-
-		LOG(2, 0, 0, "Dumping %u tunnels\n", MAXTUNNEL);
-		buf[0] = MAXTUNNEL;
-		buf[1] = sizeof(tunnelt);
-		if (fwrite(buf, sizeof(buf), 1, f) != 1)
-			break;
-		if (fwrite(tunnel, sizeof(tunnelt), MAXTUNNEL, f) != MAXTUNNEL)
-			break;
-
-		LOG(2, 0, 0, "Dumping %u sessions\n", MAXSESSION);
-		buf[0] = MAXSESSION;
-		buf[1] = sizeof(sessiont);
-		if (fwrite(buf, sizeof(buf), 1, f) != 1)
-			break;
-		if (fwrite(session, sizeof(sessiont), MAXSESSION, f) != MAXSESSION)
-			break;
-
-		if (fclose(f) == 0)
-			return ; // OK
-	}
-	while (0);
-
-	LOG(0, 0, 0, "Can't write state information: %s\n", strerror(errno));
-	unlink(STATEFILE);
-}
-
 static void build_chap_response(char *challenge, uint8_t id, uint16_t challenge_length, char **challenge_response)
 {
 	MD5_CTX ctx;
@@ -4200,13 +4107,13 @@ int sessionsetup(tunnelidt t, sessionidt s)
 
 	LOG(3, s, t, "Doing session setup for session\n");
 
-	if (!session[s].ip || session[s].ip == 0xFFFFFFFE)
+	if (!session[s].ip)
 	{
 		assign_ip_address(s);
 		if (!session[s].ip)
 		{
 			LOG(0, s, t, "   No IP allocated.  The IP address pool is FULL!\n");
-			sessionshutdown(s, "No IP addresses available");
+			sessionshutdown(s, "No IP addresses available", 2, 7);
 			return 0;
 		}
 		LOG(3, s, t, "   No IP allocated.  Assigned %s from pool\n",
@@ -4803,7 +4710,7 @@ void become_master(void)
 	{
 		for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
 		{
-			if (!session[s].tunnel) // Not an in-use session.
+			if (!session[s].opened) // Not an in-use session.
 				continue;
 
 			run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
@@ -4835,7 +4742,7 @@ int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc
 	for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
 	{
 		int idle;
-		if (!session[s].tunnel)
+		if (!session[s].opened)
 			continue;
 
 		idle = time_now - session[s].last_packet;
@@ -4873,7 +4780,7 @@ int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc
 	for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
 	{
 		int open = 0, d;
-		if (!session[s].tunnel)
+		if (!session[s].opened)
 			continue;
 
 		d = time_now - session[s].opened;
@@ -4900,75 +4807,45 @@ int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc
 
 /* Unhide an avp.
  *
- * This unencodes the AVP using the L2TP CHAP secret and the
- * previously stored random vector. It replaces the hidden data with
- * the cleartext data and returns the length of the cleartext data
- * (including the AVP "header" of 6 bytes).
- *
- * Based on code from rp-l2tpd by Roaring Penguin Software Inc.
+ * This unencodes the AVP using the L2TP secret and the previously
+ * stored random vector.  It overwrites the hidden data with the
+ * unhidden AVP subformat.
  */
-static int unhide_avp(uint8_t *avp, tunnelidt t, sessionidt s, uint16_t length)
+static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len)
 {
 	MD5_CTX ctx;
-	uint8_t *cursor;
 	uint8_t digest[16];
-	uint8_t working_vector[16];
-	uint16_t hidden_length;
-	uint8_t type[2];
-	size_t done, todo;
-	uint8_t *output;
-
-	// Find the AVP type.
-	type[0] = *(avp + 4);
-	type[1] = *(avp + 5);
-
-	// Line up with the hidden data
-	cursor = output = avp + 6;
+	uint8_t *last;
+	size_t d = 0;
 
 	// Compute initial pad
 	MD5Init(&ctx);
-	MD5Update(&ctx, type, 2);
+	MD5Update(&ctx, (uint8_t) (type >> 8) & 0xff, 1);
+	MD5Update(&ctx, (uint8_t)  type       & 0xff, 1);
 	MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
-	MD5Update(&ctx, session[s].random_vector, session[s].random_vector_length);
+	MD5Update(&ctx, vector, vec_len);
 	MD5Final(digest, &ctx);
 
-	// Get hidden length
-	hidden_length = ((uint16_t) (digest[0] ^ cursor[0])) * 256 + (uint16_t) (digest[1] ^ cursor[1]);
-
-	// Keep these for later use
-	working_vector[0] = *cursor;
-	working_vector[1] = *(cursor + 1);
-	cursor += 2;
+	// pointer to last decoded 16 octets
+	last = value;
 
-	if (hidden_length > length - 8)
+	while (len > 0)
 	{
-		LOG(1, s, t, "Hidden length %d too long in AVP of length %d\n", (int) hidden_length, (int) length);
-		return 0;
-	}
-
-	/* Decrypt remainder */
-	done = 2;
-	todo = hidden_length;
-	while (todo)
-	{
-		working_vector[done] = *cursor;
-		*output = digest[done] ^ *cursor;
-		++output;
-		++cursor;
-		--todo;
-		++done;
-		if (done == 16 && todo)
+		// calculate a new pad based on the last decoded block
+		if (d >= sizeof(digest))
 		{
-			// Compute new digest
-			done = 0;
 			MD5Init(&ctx);
 			MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
-			MD5Update(&ctx, &working_vector, 16);
+			MD5Update(&ctx, last, sizeof(digest));
 			MD5Final(digest, &ctx);
+
+			d = 0;
+			last = value;
 		}
-	}
 
-	return hidden_length + 6;
+		*value++ ^= digest[d++];
+		len--;
+	}
 }
 
 static int ip_filter_port(ip_filter_portt *p, uint16_t port)