X-Git-Url: http://git.sameswireless.fr/l2tpns.git/blobdiff_plain/9d199a1046599dc863414dda2d0a8f4202abb88d..4b0c9226f77ae52b70ee1ed676b6ef77e43d7c86:/l2tpns.c

diff --git a/l2tpns.c b/l2tpns.c
index 4eaa033..b988b78 100644
--- a/l2tpns.c
+++ b/l2tpns.c
@@ -1,10 +1,10 @@
 // L2TP Network Server
 // Adrian Kennard 2002
-// Copyright (c) 2003, 2004 Optus Internet Engineering
+// Copyright (c) 2003, 2004, 2005 Optus Internet Engineering
 // 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 1.70 2004-12-16 08:49:53 bodea Exp $";
+char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.86 2005-03-10 05:47:24 bodea Exp $";
 
 #include <arpa/inet.h>
 #include <assert.h>
@@ -19,6 +19,7 @@ char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.70 2004-12-16 08:49:53 bodea Exp
 #include <sys/mman.h>
 #include <netdb.h>
 #include <netinet/in.h>
+#include <netinet/ip6.h>
 #include <stdarg.h>
 #include <stdlib.h>
 #include <stdio.h>
@@ -62,8 +63,11 @@ int clifd = -1;			// Socket listening for CLI connections.
 int snoopfd = -1;		// UDP file handle for sending out intercept data
 int *radfds = NULL;		// RADIUS requests file handles
 int ifrfd = -1;			// File descriptor for routing, etc
+int ifr6fd = -1;		// File descriptor for IPv6 routing, etc
+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).
@@ -74,6 +78,10 @@ struct cli_session_actions *cli_session_actions = NULL;	// Pending session chang
 struct cli_tunnel_actions *cli_tunnel_actions = NULL;	// Pending tunnel changes required by CLI
 
 static void *ip_hash[256];	// Mapping from IP address to session structures.
+struct ipv6radix {
+	int sess;
+	struct ipv6radix *branch;
+} ipv6_hash[256];		// Mapping from IPv6 address to session structures.
 
 // Traffic counters.
 static uint32_t udp_rx = 0, udp_rx_pkt = 0, udp_tx = 0;
@@ -94,18 +102,19 @@ config_descriptt config_values[] = {
 	CONFIG("debug", debug, INT),
 	CONFIG("log_file", log_filename, STRING),
 	CONFIG("pid_file", pid_file, STRING),
+	CONFIG("random_device", random_device, STRING),
 	CONFIG("l2tp_secret", l2tpsecret, STRING),
-	CONFIG("primary_dns", default_dns1, IP),
-	CONFIG("secondary_dns", default_dns2, IP),
-	CONFIG("save_state", save_state, BOOL),
-	CONFIG("primary_radius", radiusserver[0], IP),
-	CONFIG("secondary_radius", radiusserver[1], IP),
+	CONFIG("primary_dns", default_dns1, IPv4),
+	CONFIG("secondary_dns", default_dns2, IPv4),
+	CONFIG("primary_radius", radiusserver[0], IPv4),
+	CONFIG("secondary_radius", radiusserver[1], IPv4),
 	CONFIG("primary_radius_port", radiusport[0], SHORT),
 	CONFIG("secondary_radius_port", radiusport[1], SHORT),
 	CONFIG("radius_accounting", radius_accounting, BOOL),
 	CONFIG("radius_secret", radiussecret, STRING),
-	CONFIG("bind_address", bind_address, IP),
-	CONFIG("peer_address", peer_address, IP),
+	CONFIG("radius_authtypes", radius_authtypes_s, STRING),
+	CONFIG("bind_address", bind_address, IPv4),
+	CONFIG("peer_address", peer_address, IPv4),
 	CONFIG("send_garp", send_garp, BOOL),
 	CONFIG("throttle_speed", rl_rate, UNSIGNED_LONG),
 	CONFIG("throttle_buckets", num_tbfs, INT),
@@ -117,10 +126,12 @@ config_descriptt config_values[] = {
 	CONFIG("scheduler_fifo", scheduler_fifo, BOOL),
 	CONFIG("lock_pages", lock_pages, BOOL),
 	CONFIG("icmp_rate", icmp_rate, INT),
-	CONFIG("cluster_address", cluster_address, IP),
+	CONFIG("packet_limit", max_packets, INT),
+	CONFIG("cluster_address", cluster_address, IPv4),
 	CONFIG("cluster_interface", cluster_interface, STRING),
 	CONFIG("cluster_hb_interval", cluster_hb_interval, INT),
 	CONFIG("cluster_hb_timeout", cluster_hb_timeout, INT),
+	CONFIG("ipv6_prefix", ipv6_prefix, IPv6),
 	{ NULL, 0, 0, 0 },
 };
 
@@ -147,7 +158,7 @@ static sessionidt shut_acct_n = 0;
 
 tunnelt *tunnel = NULL;			// Array of tunnel structures.
 sessiont *session = NULL;		// Array of session structures.
-sessioncountt *sess_count = NULL;	// Array of partial per-session traffic counters.
+sessionlocalt *sess_local = NULL;	// Array of local per-session counters.
 radiust *radius = NULL;			// Array of radius structures.
 ippoolt *ip_address_pool = NULL;	// Array of dynamic IP addresses.
 ip_filtert *ip_filters = NULL;	// Array of named filters.
@@ -159,6 +170,7 @@ struct Tringbuffer *ringbuffer = NULL;
 
 static void cache_ipmap(in_addr_t ip, int s);
 static void uncache_ipmap(in_addr_t ip);
+static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s);
 static void free_ip_address(sessionidt s);
 static void dump_acct_info(int all);
 static void sighup_handler(int sig);
@@ -166,8 +178,6 @@ 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);
@@ -177,7 +187,7 @@ 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)
@@ -203,7 +213,6 @@ clockt backoff(uint8_t try)
 void _log(int level, sessionidt s, tunnelidt t, const char *format, ...)
 {
 	static char message[65536] = {0};
-	static char message2[65536] = {0};
 	va_list ap;
 
 #ifdef RINGBUFFER
@@ -227,18 +236,13 @@ void _log(int level, sessionidt s, tunnelidt t, const char *format, ...)
 	if (config->debug < level) return;
 
 	va_start(ap, format);
+	vsnprintf(message, sizeof(message), format, ap);
+
 	if (log_stream)
-	{
-		vsnprintf(message2, 65535, format, ap);
-		snprintf(message, 65535, "%s %02d/%02d %s", time_now_string, t, s, message2);
-		fprintf(log_stream, "%s", message);
-	}
+		fprintf(log_stream, "%s %02d/%02d %s", time_now_string, t, s, message);
 	else if (syslog_log)
-	{
-		vsnprintf(message2, 65535, format, ap);
-		snprintf(message, 65535, "%02d/%02d %s", t, s, message2);
-		syslog(level + 2, message); // We don't need LOG_EMERG or LOG_ALERT
-	}
+		syslog(level + 2, "%02d/%02d %s", t, s, message); // We don't need LOG_EMERG or LOG_ALERT
+
 	va_end(ap);
 }
 
@@ -293,6 +297,72 @@ void _log_hex(int level, const char *title, const char *data, int maxsize)
 	}
 }
 
+// initialise the random generator
+static void initrandom(char *source)
+{
+	static char path[sizeof(config->random_device)] = "*undefined*";
+
+	// reinitialise only if we are forced to do so or if the config has changed
+	if (source && !strncmp(path, source, sizeof(path)))
+		return;
+
+	// close previous source, if any
+	if (rand_fd >= 0) close(rand_fd);
+
+	rand_fd = -1;
+
+	if (source)
+	{
+		// register changes
+		snprintf(path, sizeof(path), "%s", source);
+
+		if (*path == '/')
+		{
+			rand_fd = open(path, O_RDONLY|O_NONBLOCK);
+			if (rand_fd < 0)
+				LOG(0, 0, 0, "Error opening the random device %s: %s\n",
+					path, strerror(errno));
+		}
+	}
+
+	// no source: seed prng
+	{
+		unsigned seed = time_now ^ getpid();
+		LOG(4, 0, 0, "Seeding the pseudo random generator: %u\n", seed);
+		srand(seed);
+	}
+}
+
+// fill buffer with random data
+void random_data(uint8_t *buf, int len)
+{
+	int n = 0;
+
+	CSTAT(random_data);
+	if (rand_fd >= 0)
+	{
+		n = read(rand_fd, buf, len);
+		if (n >= len) return;
+		if (n < 0)
+		{
+			if (errno != EAGAIN)
+			{
+				LOG(0, 0, 0, "Error reading from random source: %s\n",
+					strerror(errno));
+
+				// fall back to rand()
+				initrandom(0);
+			}
+
+			n = 0;
+		}
+	}
+
+	// append missing data
+	while (n < len)
+		// not using the low order bits from the prng stream
+		buf[n++] = (rand() >> 4) & 0xff;
+}
 
 // Add a route
 //
@@ -357,11 +427,61 @@ static void routeset(sessionidt s, in_addr_t ip, in_addr_t mask, in_addr_t gw, i
 	}
 }
 
+void route6set(sessionidt s, struct in6_addr ip, int prefixlen, int add)
+{
+	struct in6_rtmsg rt;
+	char ipv6addr[INET6_ADDRSTRLEN];
+
+	if (ifr6fd < 0)
+	{
+		LOG(0, 0, 0, "Asked to set IPv6 route, but IPv6 not setup.\n");
+		return;
+	}
+
+	memset(&rt, 0, sizeof(rt));
+
+	memcpy(&rt.rtmsg_dst, &ip, sizeof(struct in6_addr));
+	rt.rtmsg_dst_len = prefixlen;
+	rt.rtmsg_metric = 1;
+	rt.rtmsg_flags = RTF_UP;
+	rt.rtmsg_ifindex = tunidx;
+
+	LOG(1, 0, 0, "Route %s %s/%d\n",
+	    add ? "add" : "del",
+	    inet_ntop(AF_INET6, &ip, ipv6addr, INET6_ADDRSTRLEN),
+	    prefixlen);
+
+	if (ioctl(ifr6fd, add ? SIOCADDRT : SIOCDELRT, (void *) &rt) < 0)
+		LOG(0, 0, 0, "route6set() error in ioctl: %s\n",
+				strerror(errno));
+
+	// FIXME: need to add BGP routing (RFC2858)
+
+	if (s)
+	{
+		if (!add)	// Are we deleting a route?
+			s = 0;	// Caching the session as '0' is the same as uncaching.
+
+		cache_ipv6map(ip, prefixlen, s);
+	}
+	
+	return;
+}
+
+// defined in linux/ipv6.h, but tricky to include from user-space
+// TODO: move routing to use netlink rather than ioctl
+struct in6_ifreq {
+	struct in6_addr ifr6_addr;
+	__u32 ifr6_prefixlen;
+	unsigned int ifr6_ifindex;
+};
+
 //
 // Set up TUN interface
 static void inittun(void)
 {
 	struct ifreq ifr;
+	struct in6_ifreq ifr6;
 	struct sockaddr_in sin = {0};
 	memset(&ifr, 0, sizeof(ifr));
 	ifr.ifr_flags = IFF_TUN;
@@ -407,6 +527,42 @@ static void inittun(void)
 		LOG(0, 0, 0, "Error setting tun flags: %s\n", strerror(errno));
 		exit(1);
 	}
+	if (ioctl(ifrfd, SIOCGIFINDEX, (void *) &ifr) < 0)
+	{
+		LOG(0, 0, 0, "Error getting tun ifindex: %s\n", strerror(errno));
+		exit(1);
+	}
+	tunidx = ifr.ifr_ifindex;
+
+	// Only setup IPv6 on the tun device if we have a configured prefix
+	if (config->ipv6_prefix.s6_addr[0] > 0) {
+		ifr6fd = socket(PF_INET6, SOCK_DGRAM, 0);
+
+		// Link local address is FE80::1
+		memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
+		ifr6.ifr6_addr.s6_addr[0] = 0xFE;
+		ifr6.ifr6_addr.s6_addr[1] = 0x80;
+		ifr6.ifr6_addr.s6_addr[15] = 1;
+		ifr6.ifr6_prefixlen = 64;
+		ifr6.ifr6_ifindex = ifr.ifr_ifindex;
+		if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
+		{
+			LOG(0, 0, 0, "Error setting tun IPv6 link local address:"
+				" %s\n", strerror(errno));
+		}
+
+		// Global address is prefix::1
+		memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
+		ifr6.ifr6_addr = config->ipv6_prefix;
+		ifr6.ifr6_addr.s6_addr[15] = 1;
+		ifr6.ifr6_prefixlen = 64;
+		ifr6.ifr6_ifindex = ifr.ifr_ifindex;
+		if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
+		{
+			LOG(0, 0, 0, "Error setting tun IPv6 global address: %s\n",
+				strerror(errno));
+		}
+	}
 }
 
 // set up UDP port
@@ -473,17 +629,62 @@ static int lookup_ipmap(in_addr_t ip)
 	return (int) (intptr_t) d[(size_t) *a];
 }
 
+static int lookup_ipv6map(struct in6_addr ip)
+{
+	struct ipv6radix *curnode;
+	int i;
+	int s;
+	char ipv6addr[INET6_ADDRSTRLEN];
+
+	curnode = &ipv6_hash[ip.s6_addr[0]];
+	i = 1;
+	s = curnode->sess;
+
+	while (s == 0 && i < 15 && curnode->branch != NULL)
+	{
+		curnode = &curnode->branch[ip.s6_addr[i]];
+		s = curnode->sess;
+		i++;
+	}
+
+	LOG(4, s, session[s].tunnel, "Looking up address %s and got %d\n",
+    			inet_ntop(AF_INET6, &ip, ipv6addr,
+				INET6_ADDRSTRLEN),
+			s);
+
+	return s;
+}
+
 sessionidt sessionbyip(in_addr_t ip)
 {
 	int s = lookup_ipmap(ip);
-	CSTAT(call_sessionbyip);
+	CSTAT(sessionbyip);
 
-	if (s > 0 && s < MAXSESSION && session[s].tunnel)
+	if (s > 0 && s < MAXSESSION && session[s].opened)
 		return (sessionidt) s;
 
 	return 0;
 }
 
+sessionidt sessionbyipv6(struct in6_addr ip)
+{
+	int s;
+	CSTAT(sessionbyipv6);
+
+	if (!memcmp(&config->ipv6_prefix, &ip, 8) ||
+		(ip.s6_addr[0] == 0xFE && ip.s6_addr[1] == 0x80 &&
+		 (ip.s6_addr16[1] == ip.s6_addr16[2] == ip.s6_addr16[3] == 0))) {
+		s = lookup_ipmap(*(in_addr_t *) &ip.s6_addr[8]);
+	} else {
+		s = lookup_ipv6map(ip);
+	}
+
+	if (s > 0 && s < MAXSESSION && session[s].opened)
+		return s;
+
+	return 0;
+}
+
 //
 // Take an IP address in HOST byte order and
 // add it to the sessionid by IP cache.
@@ -523,6 +724,42 @@ static void uncache_ipmap(in_addr_t ip)
 	cache_ipmap(ip, 0);	// Assign it to the NULL session.
 }
 
+static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s)
+{
+	int i;
+	int bytes;
+	struct ipv6radix *curnode;
+	char ipv6addr[INET6_ADDRSTRLEN];
+
+	curnode = &ipv6_hash[ip.s6_addr[0]];
+
+	bytes = prefixlen >> 3;
+	i = 1;
+	while (i < bytes) {
+		if (curnode->branch == NULL)
+		{
+			if (!(curnode->branch = calloc(256,
+					sizeof (struct ipv6radix))))
+				return;
+		}
+		curnode = &curnode->branch[ip.s6_addr[i]];
+		i++;
+	}
+
+	curnode->sess = s;
+
+	if (s > 0)
+		LOG(4, s, session[s].tunnel, "Caching ip address %s/%d\n",
+	    			inet_ntop(AF_INET6, &ip, ipv6addr, 
+					INET6_ADDRSTRLEN),
+				prefixlen);
+	else if (s == 0)
+		LOG(4, 0, 0, "Un-caching ip address %s/%d\n",
+	    			inet_ntop(AF_INET6, &ip, ipv6addr, 
+					INET6_ADDRSTRLEN),
+				prefixlen);
+}
+
 //
 // CLI list to dump current ipcache.
 //
@@ -576,10 +813,13 @@ int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc)
 sessionidt sessionbyuser(char *username)
 {
 	int s;
-	CSTAT(call_sessionbyuser);
+	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.
 
@@ -621,17 +861,16 @@ 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;
 }
 
@@ -640,7 +879,7 @@ void tunnelsend(uint8_t * buf, uint16_t l, tunnelidt t)
 {
 	struct sockaddr_in addr;
 
-	CSTAT(call_tunnelsend);
+	CSTAT(tunnelsend);
 
 	if (!t)
 	{
@@ -711,23 +950,23 @@ static void processipout(uint8_t * buf, int len)
 	tunnelidt t;
 	in_addr_t ip;
 
-	char * data = buf;	// Keep a copy of the originals.
+	char *data = buf;	// Keep a copy of the originals.
 	int size = len;
 
 	uint8_t b[MAXETHER + 20];
 
-	CSTAT(call_processipout);
+	CSTAT(processipout);
 
 	if (len < MIN_IP_SIZE)
 	{
 		LOG(1, 0, 0, "Short IP, %d bytes\n", len);
-		STAT(tunnel_tx_errors);
+		STAT(tun_rx_errors);
 		return;
 	}
 	if (len >= MAXETHER)
 	{
 		LOG(1, 0, 0, "Oversize IP packet %d bytes\n", len);
-		STAT(tunnel_tx_errors);
+		STAT(tun_rx_errors);
 		return;
 	}
 
@@ -765,6 +1004,45 @@ static void processipout(uint8_t * buf, int len)
 	t = session[s].tunnel;
 	sp = &session[s];
 
+	// DoS prevention: enforce a maximum number of packets per 0.1s for a session
+	if (config->max_packets > 0)
+	{
+		if (sess_local[s].last_packet_out == TIME)
+		{
+			int max = config->max_packets;
+
+			// All packets for throttled sessions are handled by the
+			// master, so further limit by using the throttle rate.
+			// A bit of a kludge, since throttle rate is in kbps,
+			// but should still be generous given our average DSL
+			// packet size is 200 bytes: a limit of 28kbps equates
+			// to around 180 packets per second.
+			if (!config->cluster_iam_master && sp->throttle_out && sp->throttle_out < max)
+				max = sp->throttle_out;
+
+			if (++sess_local[s].packets_out > max)
+			{
+				sess_local[s].packets_dropped++;
+				return;
+			}
+		}
+		else
+		{
+			if (sess_local[s].packets_dropped)
+			{
+				INC_STAT(tun_rx_dropped, sess_local[s].packets_dropped);
+				LOG(3, s, t, "Dropped %u/%u packets to %s for %suser %s\n",
+					sess_local[s].packets_dropped, sess_local[s].packets_out,
+					fmtaddr(ip, 0), sp->throttle_out ? "throttled " : "",
+					sp->user);
+			}
+
+			sess_local[s].last_packet_out = TIME;
+			sess_local[s].packets_out = 1;
+			sess_local[s].packets_dropped = 0;
+		}
+	}
+
 	// run access-list if any
 	if (session[s].filter_out && !ip_filter(buf, len, session[s].filter_out - 1))
 		return;
@@ -802,7 +1080,116 @@ static void processipout(uint8_t * buf, int len)
 	sp->total_cout += len; // byte count
 	sp->pout++;
 	udp_tx += len;
-	sess_count[s].cout += len;	// To send to master..
+	sess_local[s].cout += len;	// To send to master..
+}
+
+// process outgoing (to tunnel) IPv6
+//
+static void processipv6out(uint8_t * buf, int len)
+{
+	sessionidt s;
+	sessiont *sp;
+	tunnelidt t;
+	in_addr_t ip;
+	struct in6_addr ip6;
+
+	char *data = buf;	// Keep a copy of the originals.
+	int size = len;
+
+	uint8_t b[MAXETHER + 20];
+
+	CSTAT(processipv6out);
+
+	if (len < MIN_IP_SIZE)
+	{
+		LOG(1, 0, 0, "Short IPv6, %d bytes\n", len);
+		STAT(tunnel_tx_errors);
+		return;
+	}
+	if (len >= MAXETHER)
+	{
+		LOG(1, 0, 0, "Oversize IPv6 packet %d bytes\n", len);
+		STAT(tunnel_tx_errors);
+		return;
+	}
+
+	// Skip the tun header
+	buf += 4;
+	len -= 4;
+
+	// Got an IP header now
+	if (*(uint8_t *)(buf) >> 4 != 6)
+	{
+		LOG(1, 0, 0, "IP: Don't understand anything except IPv6\n");
+		return;
+	}
+
+	ip6 = *(struct in6_addr *)(buf+24);
+	s = sessionbyipv6(ip6);
+
+	if (s == 0)
+	{
+		ip = *(uint32_t *)(buf + 32);
+		s = sessionbyip(ip);
+	}
+	
+	if (s == 0)
+	{
+		// Is this a packet for a session that doesn't exist?
+		static int rate = 0;	// Number of ICMP packets we've sent this second.
+		static int last = 0;	// Last time we reset the ICMP packet counter 'rate'.
+
+		if (last != time_now)
+		{
+			last = time_now;
+			rate = 0;
+		}
+
+		if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
+		{
+			// FIXME: Should send icmp6 host unreachable
+		}
+		return;
+	}
+	t = session[s].tunnel;
+	sp = &session[s];
+
+	// FIXME: add DoS prevention/filters?
+
+	if (sp->tbf_out)
+	{
+		// Are we throttling this session?
+		if (config->cluster_iam_master)
+			tbf_queue_packet(sp->tbf_out, data, size);
+		else
+			master_throttle_packet(sp->tbf_out, data, size);
+		return;
+	}
+	else if (sp->walled_garden && !config->cluster_iam_master)
+	{
+		// We are walled-gardening this
+		master_garden_packet(s, data, size);
+		return;
+	}
+
+	LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
+
+	// Add on L2TP header
+	{
+		uint8_t *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIPV6);
+		if (!p) return;
+		tunnelsend(b, len + (p-b), t); // send it...
+	}
+
+	// Snooping this session, send it to intercept box
+	if (sp->snoop_ip && sp->snoop_port)
+		snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
+
+	sp->cout += len; // byte count
+	sp->total_cout += len; // byte count
+	sp->pout++;
+	udp_tx += len;
+	sess_local[s].cout += len;	// To send to master..
 }
 
 //
@@ -852,7 +1239,7 @@ static void send_ipout(sessionidt s, uint8_t *buf, int len)
 	sp->total_cout += len; // byte count
 	sp->pout++;
 	udp_tx += len;
-	sess_count[s].cout += len;	// To send to master..
+	sess_local[s].cout += len;	// To send to master..
 }
 
 // add an AVP (16 bit)
@@ -877,7 +1264,7 @@ 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);
@@ -972,7 +1359,7 @@ 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)
@@ -1008,9 +1395,9 @@ 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)
@@ -1051,11 +1438,11 @@ void sessionshutdown(sessionidt s, char *reason)
 	int walled_garden = session[s].walled_garden;
 
 
-	CSTAT(call_sessionshutdown);
+	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
 	}
 
@@ -1066,7 +1453,7 @@ void sessionshutdown(sessionidt s, char *reason)
 		run_plugins(PLUGIN_KILL_SESSION, &data);
 	}
 
-	if (session[s].opened && !walled_garden && !session[s].die)
+	if (!walled_garden && !session[s].die)
 	{
 		// RADIUS Stop message
 		uint16_t r = session[s].radius;
@@ -1079,9 +1466,7 @@ void sessionshutdown(sessionidt s, char *reason)
 			}
 			else
 			{
-				int n;
-				for (n = 0; n < 15; n++)
-					radius[r].auth[n] = rand();
+				random_data(radius[r].auth, sizeof(radius[r].auth));
 			}
 		}
 
@@ -1114,6 +1499,10 @@ void sessionshutdown(sessionidt s, char *reason)
 		}
 		else
 			free_ip_address(s);
+
+		// unroute IPv6, if setup
+		if (session[s].flags & SF_IPV6_ROUTED)
+			route6set(s, session[s].ipv6route, session[s].ipv6prefixlen, 0);
 	}
 
 	if (session[s].throttle_in || session[s].throttle_out) // Unthrottle if throttled.
@@ -1127,7 +1516,7 @@ void sessionshutdown(sessionidt s, char *reason)
 	}
 
 	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--;
@@ -1142,7 +1531,7 @@ void sendipcp(tunnelidt t, sessionidt s)
 	uint16_t r = session[s].radius;
 	uint8_t *q;
 
-	CSTAT(call_sendipcp);
+	CSTAT(sendipcp);
 
 	if (!r)
 		r = radiusnew(s);
@@ -1175,15 +1564,48 @@ void sendipcp(tunnelidt t, sessionidt s)
 
 	tunnelsend(buf, 10 + (q - buf), t); // send it
 	session[s].flags &= ~SF_IPCP_ACKED;	// Clear flag.
+
+	// If we have an IPv6 prefix length configured, assume we should
+	// try to negotiate an IPv6 session as well. Unless we've had a
+	// (N)ACK for IPV6CP.
+	if (config->ipv6_prefix.s6_addr[0] > 0 && 
+			!(session[s].flags & SF_IPV6CP_ACKED) &&
+			!(session[s].flags & SF_IPV6_NACKED))
+	{
+		q = makeppp(buf,sizeof(buf), 0, 0, t, s, PPPIPV6CP);
+		if (!q) return;
+
+		*q = ConfigReq;
+		q[1] = r << RADIUS_SHIFT;		// ID, don't care, we
+							// only send one type
+							// of request
+		*(uint16_t *) (q + 2) = htons(14);
+		q[4] = 1;
+		q[5] = 10;
+		*(uint32_t *) (q + 6) = 0;		// We'll be prefix::1
+		*(uint32_t *) (q + 10) = 0;
+		q[13] = 1;
+
+		tunnelsend(buf, 14 + (q - buf), t);	// send it
+	}
 }
 
 // kill a session now
-static void sessionkill(sessionidt s, char *reason)
+void sessionkill(sessionidt s, char *reason)
 {
 
-	CSTAT(call_sessionkill);
+	CSTAT(sessionkill);
 
-	session[s].die = now();
+	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);  // close radius/routes, etc.
 	if (session[s].radius)
 		radiusclear(session[s].radius, s); // cant send clean accounting data, session is killed
@@ -1211,7 +1633,7 @@ static void tunnelkill(tunnelidt t, char *reason)
 	sessionidt s;
 	controlt *c;
 
-	CSTAT(call_tunnelkill);
+	CSTAT(tunnelkill);
 
 	tunnel[t].state = TUNNELDIE;
 
@@ -1225,23 +1647,23 @@ 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;
 
-	CSTAT(call_tunnelshutdown);
+	CSTAT(tunnelshutdown);
 
 	if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
 	{
@@ -1252,19 +1674,40 @@ 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);
 
 	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
 	}
 }
 
@@ -1276,7 +1719,7 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
 	uint8_t *p = buf + 2;
 
 
-	CSTAT(call_processudp);
+	CSTAT(processudp);
 
 	udp_rx += len;
 	udp_rx_pkt++;
@@ -1339,7 +1782,7 @@ 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
@@ -1355,7 +1798,10 @@ 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);
@@ -1465,71 +1911,111 @@ 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, avpnames[mtype], n);
+				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);
-					LOG(4, s, t, "   Message type = %d (%s)\n", *b, l2tp_message_types[message]);
-					mandatorymessage = flags;
+					mandatory = flags & 0x80;
+					LOG(4, s, t, "   Message type = %d (%s)\n", *b, l2tp_message_type(message));
 					break;
 				case 1:     // result code
 					{
@@ -1537,23 +2023,18 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
 						const char* resdesc = "(unknown)";
 						if (message == 4)
 						{ /* StopCCN */
-							if (rescode <= MAX_STOPCCN_RESULT_CODE)
-								resdesc = stopccn_result_codes[rescode];
+							resdesc = stopccn_result_code(rescode);
 						}
 						else if (message == 14)
 						{ /* CDN */
-							if (rescode <= MAX_CDN_RESULT_CODE)
-								resdesc = cdn_result_codes[rescode];
+							resdesc = cdn_result_code(rescode);
 						}
 
 						LOG(4, s, t, "   Result Code %d: %s\n", rescode, resdesc);
 						if (n >= 4)
 						{
 							uint16_t errcode = ntohs(*(uint16_t *)(b + 2));
-							const char* errdesc = "(unknown)";
-							if (errcode <= MAX_ERROR_CODE)
-								errdesc = error_codes[errcode];
-							LOG(4, s, t, "   Error Code %d: %s\n", errcode, errdesc);
+							LOG(4, s, t, "   Error Code %d: %s\n", errcode, error_code(errcode));
 						}
 						if (n > 4)
 							LOG(4, s, t, "   Error String: %.*s\n", n-4, b+4);
@@ -1569,6 +2050,9 @@ 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
 						}
 					}
@@ -1681,9 +2165,9 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
 					}
 				case 29:    // Proxy Authentication Type
 					{
-						uint16_t authtype = ntohs(*(uint16_t *)b);
-						LOG(4, s, t, "   Proxy Auth Type %d (%s)\n", authtype, authtypes[authtype]);
-						requestchap = (authtype == 2);
+						uint16_t atype = ntohs(*(uint16_t *)b);
+						LOG(4, s, t, "   Proxy Auth Type %d (%s)\n", atype, auth_type(atype));
+						requestchap = (atype == 2);
 						break;
 					}
 				case 30:    // Proxy Authentication Name
@@ -1745,14 +2229,20 @@ 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)
 				{
@@ -1777,8 +2267,7 @@ 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
@@ -1796,7 +2285,8 @@ 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
 					{
@@ -1820,19 +2310,16 @@ 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;
 						LOG(3, s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
 						control16(c, 14, s, 1); // assigned session
 						controladd(c, t, s); // send the reply
-						{
-							// Generate a random challenge
-							int n;
-							for (n = 0; n < 15; n++)
-								radius[r].auth[n] = rand();
-						}
+
+						// Generate a random challenge
+						random_data(radius[r].auth, sizeof(radius[r].auth));
 						strncpy(radius[r].calling, calling, sizeof(radius[r].calling) - 1);
 						strncpy(session[s].called, called, sizeof(session[s].called) - 1);
 						strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
@@ -1861,8 +2348,8 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
 					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;
@@ -1903,7 +2390,7 @@ 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)
 			{
@@ -1913,9 +2400,7 @@ 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;
 		}
@@ -1944,6 +2429,19 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
 			if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
 			processipcp(t, s, p, l);
 		}
+		else if (prot == PPPIPV6CP)
+		{
+			if (config->ipv6_prefix.s6_addr[0] > 0)
+			{
+				session[s].last_packet = time_now;
+				if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
+				processipv6cp(t, s, p, l);
+			}
+			else
+			{
+				LOG(1, s, t, "IPv6 not configured; ignoring IPv6CP\n");
+			}
+		}
 		else if (prot == PPPCCP)
 		{
 			session[s].last_packet = time_now;
@@ -1967,6 +2465,28 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
 
 			processipin(t, s, p, l);
 		}
+		else if (prot == PPPIPV6)
+		{
+			if (!config->ipv6_prefix.s6_addr[0] > 0)
+			{
+				LOG(1, s, t, "IPv6 not configured; yet received IPv6 packet. Ignoring.\n");
+				return;
+			}
+			if (session[s].die)
+			{
+				LOG(4, s, t, "Session %d is closing.  Don't process PPP packets\n", s);
+				return;              // closing session, PPP not processed
+			}
+
+			session[s].last_packet = time_now;
+			if (session[s].walled_garden && !config->cluster_iam_master)
+			{
+				master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
+				return;
+			}
+
+			processipv6in(t, s, p, l);
+		}
 		else
 		{
 			STAT(tunnel_rx_errors);
@@ -1982,7 +2502,7 @@ static void processtun(uint8_t * buf, int len)
 	STAT(tun_rx_packets);
 	INC_STAT(tun_rx_bytes, len);
 
-	CSTAT(call_processtun);
+	CSTAT(processtun);
 
 	eth_rx_pkt++;
 	eth_rx += len;
@@ -1993,8 +2513,12 @@ static void processtun(uint8_t * buf, int len)
 		return;
 	}
 
-	if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IP
+	if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IPv4
 		processipout(buf, len);
+	else if (*(uint16_t *) (buf + 2) == htons(PKTIPV6) // IPV6
+	    && config->ipv6_prefix.s6_addr[0] > 0)
+		processipv6out(buf, len);
+
 	// Else discard.
 }
 
@@ -2070,7 +2594,7 @@ 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);
 			}
 		}
 
@@ -2083,7 +2607,7 @@ 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))
@@ -2346,6 +2870,8 @@ static void mainloop(void)
 		n = select(n + 1, &r, 0, 0, &to);
 #endif /* BGP */
 
+		STAT(select_called);
+
 		TIME = now();
 		if (n < 0)
 		{
@@ -2464,9 +2990,16 @@ static void mainloop(void)
 				}
 			}
 
+			if (udp_pkts > 1 || tun_pkts > 1 || cluster_pkts > 1)
+				STAT(multi_read_used);
+
 			if (c >= config->multi_read_count)
+			{
 				LOG(3, 0, 0, "Reached multi_read_count (%d); processed %d udp, %d tun and %d cluster packets\n",
-					udp_pkts, tun_pkts, cluster_pkts);
+					config->multi_read_count, udp_pkts, tun_pkts, cluster_pkts);
+
+				STAT(multi_read_exceeded);
+			}
 		}
 
 			// Runs on every machine (master and slaves).
@@ -2616,6 +3149,7 @@ static void initdata(int optdebug, char *optconfig)
 	config->debug = optdebug;
 	config->num_tbfs = MAXTBFS;
 	config->rl_rate = 28; // 28kbps
+	strcpy(config->random_device, RANDOMDEVICE);
 
 	if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)))
 	{
@@ -2628,9 +3162,9 @@ static void initdata(int optdebug, char *optconfig)
 		exit(1);
 	}
 
-	if (!(sess_count = shared_malloc(sizeof(sessioncountt) * MAXSESSION)))
+	if (!(sess_local = shared_malloc(sizeof(sessionlocalt) * MAXSESSION)))
 	{
-		LOG(0, 0, 0, "Error doing malloc for sessions_count: %s\n", strerror(errno));
+		LOG(0, 0, 0, "Error doing malloc for sess_local: %s\n", strerror(errno));
 		exit(1);
 	}
 
@@ -2646,12 +3180,12 @@ static void initdata(int optdebug, char *optconfig)
 		exit(1);
 	}
 
-if (!(ip_filters = shared_malloc(sizeof(ip_filtert) * MAXFILTER)))
-{
-	LOG(0, 0, 0, "Error doing malloc for ip_filters: %s\n", strerror(errno));
-	exit(1);
-}
-memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
+	if (!(ip_filters = shared_malloc(sizeof(ip_filtert) * MAXFILTER)))
+	{
+		LOG(0, 0, 0, "Error doing malloc for ip_filters: %s\n", strerror(errno));
+		exit(1);
+	}
+	memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
 
 #ifdef RINGBUFFER
 	if (!(ringbuffer = shared_malloc(sizeof(struct Tringbuffer))))
@@ -2682,7 +3216,7 @@ memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
 	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.
@@ -2691,7 +3225,7 @@ memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
 	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)
@@ -2721,7 +3255,7 @@ static int assign_ip_address(sessionidt s)
 	char reuse = 0;
 
 
-	CSTAT(call_assign_ip_address);
+	CSTAT(assign_ip_address);
 
 	for (i = 1; i < ip_pool_size; i++)
 	{
@@ -2774,7 +3308,7 @@ static void free_ip_address(sessionidt s)
 	int i = session[s].ip_pool_index;
 
 
-	CSTAT(call_free_ip_address);
+	CSTAT(free_ip_address);
 
 	if (!session[s].ip)
 		return; // what the?
@@ -2817,8 +3351,9 @@ 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)
@@ -3045,7 +3580,7 @@ static void dump_acct_info(int all)
 	FILE *f = NULL;
 
 
-	CSTAT(call_dump_acct_info);
+	CSTAT(dump_acct_info);
 
 	if (shut_acct_n)
 	{
@@ -3119,7 +3654,7 @@ int main(int argc, char *argv[])
 	init_tbf(config->num_tbfs);
 
 	LOG(0, 0, 0, "L2TPNS version " VERSION "\n");
-	LOG(0, 0, 0, "Copyright (c) 2003, 2004 Optus Internet Engineering\n");
+	LOG(0, 0, 0, "Copyright (c) 2003, 2004, 2005 Optus Internet Engineering\n");
 	LOG(0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
 	{
 		struct rlimit rlim;
@@ -3182,8 +3717,6 @@ int main(int argc, char *argv[])
 	initrad();
 	initippool();
 
-	read_state();
-
 	signal(SIGHUP, sighup_handler);
 	signal(SIGTERM, sigterm_handler);
 	signal(SIGINT, sigterm_handler);
@@ -3275,9 +3808,6 @@ 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++;
 }
 
@@ -3297,7 +3827,7 @@ 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);
 		}
 	}
 
@@ -3310,182 +3840,6 @@ 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;
@@ -3524,6 +3878,7 @@ static int facility_value(char *name)
 static void update_config()
 {
 	int i;
+	char *p;
 	static int timeout = 0;
 	static int interval = 0;
 
@@ -3535,6 +3890,7 @@ static void update_config()
 		fclose(log_stream);
 		log_stream = NULL;
 	}
+
 	if (*config->log_filename)
 	{
 		if (strstr(config->log_filename, "syslog:") == config->log_filename)
@@ -3566,7 +3922,6 @@ static void update_config()
 		setbuf(log_stream, NULL);
 	}
 
-
 	// Update radius
 	config->numradiusservers = 0;
 	for (i = 0; i < MAXRADSERVER; i++)
@@ -3591,6 +3946,59 @@ static void update_config()
 
 	config->num_radfds = 2 << RADIUS_SHIFT;
 
+	// parse radius_authtypes_s
+	config->radius_authtypes = config->radius_authprefer = 0;
+	p = config->radius_authtypes_s;
+	while (*p)
+	{
+		char *s = strpbrk(p, " \t,");
+		int type = 0;
+
+		if (s)
+		{
+			*s++ = 0;
+			while (*s == ' ' || *s == '\t')
+				s++;
+
+			if (!*s)
+				s = 0;
+		}
+
+		if (!strncasecmp("chap", p, strlen(p)))
+			type = AUTHCHAP;
+		else if (!strncasecmp("pap", p, strlen(p)))
+			type = AUTHPAP;
+		else
+			LOG(0, 0, 0, "Invalid RADIUS authentication type \"%s\"", p);
+
+		config->radius_authtypes |= type;
+		if (!config->radius_authprefer)
+			config->radius_authprefer = type;
+	}
+
+	if (!config->radius_authtypes)
+	{
+		LOG(0, 0, 0, "Defaulting to PAP authentication\n");
+		config->radius_authtypes = config->radius_authprefer = AUTHPAP;
+	}
+
+	// normalise radius_authtypes_s
+	if (config->radius_authprefer == AUTHPAP)
+	{
+		strcpy(config->radius_authtypes_s, "pap");
+		if (config->radius_authtypes & AUTHCHAP)
+			strcat(config->radius_authtypes_s, ", chap");
+	}
+	else
+	{
+		strcpy(config->radius_authtypes_s, "chap");
+		if (config->radius_authtypes & AUTHPAP)
+			strcat(config->radius_authtypes_s, ", pap");
+	}
+
+	// re-initialise the random number source
+	initrandom(config->random_device);
+
 	// Update plugins
 	for (i = 0; i < MAXPLUGINS; i++)
 	{
@@ -3608,6 +4016,7 @@ static void update_config()
 			remove_plugin(config->old_plugins[i]);
 		}
 	}
+
 	memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
 	if (!config->cleanup_interval) config->cleanup_interval = 10;
 	if (!config->multi_read_count) config->multi_read_count = 10;
@@ -3686,11 +4095,11 @@ int sessionsetup(tunnelidt t, sessionidt s)
 	sessionidt i;
 	int r;
 
-	CSTAT(call_sessionsetup);
+	CSTAT(sessionsetup);
 
 	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)
@@ -3739,6 +4148,7 @@ int sessionsetup(tunnelidt t, sessionidt s)
 		// convered by a Framed-Route.  Anything else is part
 		// of the IP address pool and is already routed, it
 		// just needs to be added to the IP cache.
+		// IPv6 route setup is done in ppp.c, when IPV6CP is acked.
 		if (session[s].ip_pool_index == -1) // static ip
 		{
 			if (!routed) routeset(s, session[s].ip, 0, 0, 1);
@@ -3861,6 +4271,10 @@ int load_session(sessionidt s, sessiont *new)
 		}
 	}
 
+	// check v6 routing
+	if (new->flags & SF_IPV6_ROUTED && !(session[s].flags & SF_IPV6_ROUTED))
+		    route6set(s, new->ipv6route, new->ipv6prefixlen, 1);
+
 	// check filters
 	if (new->filter_in && (new->filter_in > MAXFILTER || !ip_filters[new->filter_in - 1].name[0]))
 	{
@@ -4288,7 +4702,7 @@ 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]);
@@ -4320,7 +4734,7 @@ 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;
@@ -4358,7 +4772,7 @@ 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;
@@ -4385,75 +4799,45 @@ 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;
-
-	if (hidden_length > length - 8)
-	{
-		LOG(1, s, t, "Hidden length %d too long in AVP of length %d\n", (int) hidden_length, (int) length);
-		return 0;
-	}
+	// pointer to last decoded 16 octets
+	last = value;
 
-	/* Decrypt remainder */
-	done = 2;
-	todo = hidden_length;
-	while (todo)
+	while (len > 0)
 	{
-		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)