X-Git-Url: http://git.sameswireless.fr/l2tpns.git/blobdiff_plain/8a8b45c1741ad0338391dd98726f86bc76f6c706..3175a088324635b8e1e185da1b52b8424c7c9ca7:/l2tpns.c?ds=inline

diff --git a/l2tpns.c b/l2tpns.c
index b988c7f..488287f 100644
--- a/l2tpns.c
+++ b/l2tpns.c
@@ -1,8 +1,11 @@
 // L2TP Network Server
 // Adrian Kennard 2002
-// (c) Copyrigth 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd)
+// Copyright (c) 2003, 2004 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 1.61 2004-11-29 03:55:21 bodea Exp $";
+
 #include <arpa/inet.h>
 #include <assert.h>
 #include <errno.h>
@@ -16,24 +19,26 @@
 #include <sys/mman.h>
 #include <netdb.h>
 #include <netinet/in.h>
-#include <signal.h>
 #include <stdarg.h>
 #include <stdlib.h>
 #include <stdio.h>
-#define __USE_GNU
 #include <string.h>
+#include <ctype.h>
 #include <sys/ioctl.h>
 #include <sys/socket.h>
 #include <sys/stat.h>
 #include <sys/time.h>
 #include <sys/resource.h>
-#include <sys/types.h>
 #include <sys/wait.h>
 #include <linux/if.h>
 #include <stddef.h>
 #include <time.h>
 #include <dlfcn.h>
 #include <unistd.h>
+#include <sched.h>
+#include <sys/sysinfo.h>
+#include <libcli.h>
+
 #include "md5.h"
 #include "l2tpns.h"
 #include "cluster.h"
@@ -42,67 +47,84 @@
 #include "constants.h"
 #include "control.h"
 #include "util.h"
+#include "tbf.h"
+
+#ifdef BGP
+#include "bgp.h"
+#endif /* BGP */
 
 // Globals
-struct configt *config = NULL;	// all configuration
-int tapfd = -1;			// tap interface file handle
+configt *config = NULL;		// all configuration
+int tunfd = -1;			// tun interface file handle. (network device)
 int udpfd = -1;			// UDP file handle
 int controlfd = -1;		// Control signal handle
+int clifd = -1;			// Socket listening for CLI connections.
 int snoopfd = -1;		// UDP file handle for sending out intercept data
-int radfd = -1;			// RADIUS requests file handle
+int *radfds = NULL;		// RADIUS requests file handles
 int ifrfd = -1;			// File descriptor for routing, etc
 time_t basetime = 0;		// base clock
 char hostname[1000] = "";	// us.
-ipt myip = 0;			// MY IP
-u16 tapmac[3];			// MAC of tap interface
-int tapidx;			// ifr_ifindex of tap device
-u32 sessionid = 0;		// session id for radius accounting
-int syslog_log = 0;		// are we logging to syslog
-FILE *log_stream = NULL;
-struct sockaddr_in snoop_addr = {0};
-extern int cluster_sockfd;
-unsigned long last_sid = 0;
-int handle_interface = 0;
-int clifd = 0;
-sessionidt *cli_session_kill = NULL;
-tunnelidt *cli_tunnel_kill = NULL;
-static void *ip_hash[256];
-unsigned long udp_tx = 0, udp_rx = 0, udp_rx_pkt = 0;
-unsigned long eth_tx = 0, eth_rx = 0, eth_rx_pkt = 0;
-unsigned int ip_pool_size = 0;
-time_t time_now;
-char time_now_string[64] = {0};
-char main_quit = 0;
-char *_program_name = NULL;
+static u32 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.
+u32 last_id = 0;		// Last used PPP SID. Can I kill this?? -- mo
+
+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
+
+static void *ip_hash[256];	// Mapping from IP address to session structures.
+
+// Traffic counters.
+static u32 udp_rx = 0, udp_rx_pkt = 0, udp_tx = 0;
+static u32 eth_rx = 0, eth_rx_pkt = 0;
+u32 eth_tx = 0;
+
+static u32 ip_pool_size = 1;		// Size of the pool of addresses used for dynamic address allocation.
+time_t time_now = 0;			// Current time in seconds since epoch.
+static char time_now_string[64] = {0};	// Current time as a string.
+static char main_quit = 0;		// True if we're in the process of exiting.
 linked_list *loaded_plugins;
 linked_list *plugins[MAX_PLUGIN_TYPES];
 
 #define membersize(STRUCT, MEMBER) sizeof(((STRUCT *)0)->MEMBER)
-#define CONFIG(NAME, MEMBER, TYPE) { NAME, offsetof(struct configt, MEMBER), membersize(struct configt, MEMBER), TYPE }
+#define CONFIG(NAME, MEMBER, TYPE) { NAME, offsetof(configt, MEMBER), membersize(configt, MEMBER), TYPE }
 
-struct config_descriptt config_values[] = {
+config_descriptt config_values[] = {
 	CONFIG("debug", debug, INT),
 	CONFIG("log_file", log_filename, STRING),
+	CONFIG("pid_file", pid_file, 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("snoop_host", snoop_destination_host, IP),
-	CONFIG("snoop_port", snoop_destination_port, SHORT),
 	CONFIG("primary_radius", radiusserver[0], IP),
 	CONFIG("secondary_radius", radiusserver[1], IP),
+	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("cluster_master", cluster_address, IP),
+	CONFIG("peer_address", peer_address, IP),
+	CONFIG("send_garp", send_garp, BOOL),
 	CONFIG("throttle_speed", rl_rate, UNSIGNED_LONG),
+	CONFIG("throttle_buckets", num_tbfs, INT),
 	CONFIG("accounting_dir", accounting_dir, STRING),
 	CONFIG("setuid", target_uid, INT),
 	CONFIG("dump_speed", dump_speed, BOOL),
+	CONFIG("cleanup_interval", cleanup_interval, INT),
+	CONFIG("multi_read_count", multi_read_count, INT),
+	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("cluster_interface", cluster_interface, STRING),
+	CONFIG("cluster_hb_interval", cluster_hb_interval, INT),
+	CONFIG("cluster_hb_timeout", cluster_hb_timeout, INT),
 	{ NULL, 0, 0, 0 },
 };
 
-char *plugin_functions[] = {
+static char *plugin_functions[] = {
 	NULL,
 	"plugin_pre_auth",
 	"plugin_post_auth",
@@ -113,35 +135,48 @@ char *plugin_functions[] = {
 	"plugin_kill_session",
 	"plugin_control",
 	"plugin_radius_response",
+	"plugin_become_master",
+	"plugin_new_session_master",
 };
+
 #define max_plugin_functions (sizeof(plugin_functions) / sizeof(char *))
 
-tunnelt *tunnel = NULL;		// 1000 * 45 = 45000 = 45k
-sessiont *session = NULL;	// 5000 * 213 = 1065000 = 1 Mb
-radiust *radius = NULL;
-ippoolt *ip_address_pool = NULL;
-controlt *controlfree = 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.
+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.
+static controlt *controlfree = 0;
 struct Tstats *_statistics = NULL;
 #ifdef RINGBUFFER
 struct Tringbuffer *ringbuffer = NULL;
 #endif
-tbft *filter_buckets = NULL;
-
-void sigalrm_handler(int);
-void sighup_handler(int);
-void sigterm_handler(int);
-void sigquit_handler(int);
-void sigchild_handler(int);
-void sigsegv_handler(int);
-void read_config_file();
-void read_state();
-void dump_state();
-void tunnel_clean();
-tunnelidt new_tunnel();
-void update_config();
-
-// return internal time (10ths since run)
-clockt now(void)
+
+static void cache_ipmap(ipt ip, int s);
+static void uncache_ipmap(ipt ip);
+static void free_ip_address(sessionidt s);
+static void dump_acct_info(void);
+static void sighup_handler(int sig);
+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, u8 id, u16 challenge_length, char **challenge_response);
+static void update_config(void);
+static void read_config_file(void);
+static void initplugins(void);
+static int add_plugin(char *plugin_name);
+static int remove_plugin(char *plugin_name);
+static void plugins_done(void);
+static void processcontrol(u8 * buf, int len, struct sockaddr_in *addr, int alen);
+static tunnelidt new_tunnel(void);
+static int unhide_avp(u8 *avp, tunnelidt t, sessionidt s, u16 length);
+
+// return internal time (10ths since process startup)
+static clockt now(void)
 {
 	struct timeval t;
 	gettimeofday(&t, 0);
@@ -149,16 +184,22 @@ clockt now(void)
 }
 
 // work out a retry time based on try number
+// This is a straight bounded exponential backoff.
+// Maximum re-try time is 32 seconds. (2^5).
 clockt backoff(u8 try)
 {
 	if (try > 5) try = 5;                  // max backoff
 	return now() + 10 * (1 << try);
 }
 
-void _log(int level, ipt address, sessionidt s, tunnelidt t, const char *format, ...)
+
+//
+// Log a debug message.  Typically called via the LOG macro
+//
+void _log(int level, sessionidt s, tunnelidt t, const char *format, ...)
 {
-	static char message[65535] = {0};
-	static char message2[65535] = {0};
+	static char message[65536] = {0};
+	static char message2[65536] = {0};
 	va_list ap;
 
 #ifdef RINGBUFFER
@@ -171,7 +212,6 @@ void _log(int level, ipt address, sessionidt s, tunnelidt t, const char *format,
 				ringbuffer->head = 0;
 
 		ringbuffer->buffer[ringbuffer->tail].level = level;
-		ringbuffer->buffer[ringbuffer->tail].address = address;
 		ringbuffer->buffer[ringbuffer->tail].session = s;
 		ringbuffer->buffer[ringbuffer->tail].tunnel = t;
 		va_start(ap, format);
@@ -187,7 +227,7 @@ void _log(int level, ipt address, sessionidt s, tunnelidt t, const char *format,
 	{
 		vsnprintf(message2, 65535, format, ap);
 		snprintf(message, 65535, "%s %02d/%02d %s", time_now_string, t, s, message2);
-		fprintf(log_stream, message);
+		fprintf(log_stream, "%s", message);
 	}
 	else if (syslog_log)
 	{
@@ -198,17 +238,17 @@ void _log(int level, ipt address, sessionidt s, tunnelidt t, const char *format,
 	va_end(ap);
 }
 
-void _log_hex(int level, ipt address, sessionidt s, tunnelidt t, const char *title, const char *data, int maxsize)
+void _log_hex(int level, const char *title, const char *data, int maxsize)
 {
 	int i, j;
-	unsigned const char *d = (unsigned const char *)data;
+	const u8 *d = (const u8 *)data;
 
 	if (config->debug < level) return;
 
-	// No support for log_hex to syslog
+	// No support for _log_hex to syslog
 	if (log_stream)
 	{
-		log(level, address, s, t, "%s (%d bytes):\n", title, maxsize);
+		_log(level, 0, 0, "%s (%d bytes):\n", title, maxsize);
 		setvbuf(log_stream, NULL, _IOFBF, 16384);
 
 		for (i = 0; i < maxsize; )
@@ -251,80 +291,122 @@ void _log_hex(int level, ipt address, sessionidt s, tunnelidt t, const char *tit
 
 
 // Add a route
-void routeset(ipt ip, ipt mask, ipt gw, u8 add)
+//
+// This adds it to the routing table, advertises it
+// via BGP if enabled, and stuffs it into the
+// 'sessionbyip' cache.
+//
+// 'ip' and 'mask' must be in _host_ order.
+//
+static void routeset(sessionidt s, ipt ip, ipt mask, ipt gw, u8 add)
 {
 	struct rtentry r;
+	int i;
+
+	if (!mask) mask = 0xffffffff;
+
+	ip &= mask;		// Force the ip to be the first one in the route.
+
 	memset(&r, 0, sizeof(r));
-	r.rt_dev = config->tapdevice;
+	r.rt_dev = config->tundevice;
 	r.rt_dst.sa_family = AF_INET;
 	*(u32 *) & (((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr) = htonl(ip);
 	r.rt_gateway.sa_family = AF_INET;
 	*(u32 *) & (((struct sockaddr_in *) &r.rt_gateway)->sin_addr.s_addr) = htonl(gw);
 	r.rt_genmask.sa_family = AF_INET;
-	*(u32 *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask ? mask : 0xFFFFFFF);
+	*(u32 *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask);
 	r.rt_flags = (RTF_UP | RTF_STATIC);
 	if (gw)
 		r.rt_flags |= RTF_GATEWAY;
-	else
+	else if (mask == 0xffffffff)
 		r.rt_flags |= RTF_HOST;
-	if (ioctl(ifrfd, add ? SIOCADDRT : SIOCDELRT, (void *) &r) < 0) perror("routeset");
-	log(1, ip, 0, 0, "Route %s %u.%u.%u.%u/%u.%u.%u.%u %u.%u.%u.%u\n", add ? "Add" : "Del", ip >> 24, ip >> 16 & 255, ip >> 8 & 255, ip & 255, mask >> 24, mask >> 16 & 255, mask >> 8 & 255, mask & 255, gw >> 24, gw >> 16 & 255, gw >> 8 & 255, gw & 255);
+
+	LOG(1, s, 0, "Route %s %s/%s%s%s\n", add ? "add" : "del",
+	    fmtaddr(htonl(ip), 0), fmtaddr(htonl(mask), 1),
+	    gw ? " via" : "", gw ? fmtaddr(htonl(gw), 2) : "");
+
+	if (ioctl(ifrfd, add ? SIOCADDRT : SIOCDELRT, (void *) &r) < 0)
+		LOG(0, 0, 0, "routeset() error in ioctl: %s\n", strerror(errno));
+
+#ifdef BGP
+	if (add)
+		bgp_add_route(htonl(ip), htonl(mask));
+	else
+		bgp_del_route(htonl(ip), htonl(mask));
+#endif /* BGP */
+
+		// Add/Remove the IPs to the 'sessionbyip' cache.
+		// Note that we add the zero address in the case of
+		// a network route. Roll on CIDR.
+
+		// Note that 's == 0' implies this is the address pool.
+		// We still cache it here, because it will pre-fill
+		// the malloc'ed tree.
+
+	if (s)
+	{
+		if (!add)	// Are we deleting a route?
+			s = 0;	// Caching the session as '0' is the same as uncaching.
+
+		for (i = ip; (i&mask) == (ip&mask) ; ++i)
+			cache_ipmap(i, s);
+	}
 }
 
-// Set up TAP interface
-void inittap(void)
+//
+// Set up TUN interface
+static void inittun(void)
 {
 	struct ifreq ifr;
 	struct sockaddr_in sin = {0};
 	memset(&ifr, 0, sizeof(ifr));
 	ifr.ifr_flags = IFF_TUN;
 
-	tapfd = open(TAPDEVICE, O_RDWR);
-	if (tapfd < 0)
+	tunfd = open(TUNDEVICE, O_RDWR);
+	if (tunfd < 0)
 	{                          // fatal
-		log(0, 0, 0, 0, "Can't open %s: %s\n", TAPDEVICE, strerror(errno));
-		exit(-1);
+		LOG(0, 0, 0, "Can't open %s: %s\n", TUNDEVICE, strerror(errno));
+		exit(1);
+	}
+	{
+		int flags = fcntl(tunfd, F_GETFL, 0);
+		fcntl(tunfd, F_SETFL, flags | O_NONBLOCK);
 	}
-	if (ioctl(tapfd, TUNSETIFF, (void *) &ifr) < 0)
+	if (ioctl(tunfd, TUNSETIFF, (void *) &ifr) < 0)
 	{
-		log(0, 0, 0, 0, "Can't set tap interface: %s\n", strerror(errno));
-		exit(-1);
+		LOG(0, 0, 0, "Can't set tun interface: %s\n", strerror(errno));
+		exit(1);
 	}
-	assert(strlen(ifr.ifr_name) < sizeof(config->tapdevice));
-	strncpy(config->tapdevice, ifr.ifr_name, sizeof(config->tapdevice) - 1);
+	assert(strlen(ifr.ifr_name) < sizeof(config->tundevice));
+	strncpy(config->tundevice, ifr.ifr_name, sizeof(config->tundevice) - 1);
 	ifrfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
 
 	sin.sin_family = AF_INET;
-	sin.sin_addr.s_addr = handle_interface ? config->bind_address : 0x01010101; // 1.1.1.1
+	sin.sin_addr.s_addr = config->bind_address ? config->bind_address : 0x01010101; // 1.1.1.1
 	memcpy(&ifr.ifr_addr, &sin, sizeof(struct sockaddr));
 
 	if (ioctl(ifrfd, SIOCSIFADDR, (void *) &ifr) < 0)
 	{
-		perror("set tap addr");
-		exit( -1);
-	}
-	ifr.ifr_flags = IFF_UP;
-	if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0)
-	{
-		perror("set tap flags");
-		exit( -1);
+		LOG(0, 0, 0, "Error setting tun address: %s\n", strerror(errno));
+		exit(1);
 	}
-	if (ioctl(ifrfd, SIOCGIFHWADDR, (void *) &ifr) < 0)
+	/* Bump up the qlen to deal with bursts from the network */
+	ifr.ifr_qlen = 1000;
+	if (ioctl(ifrfd, SIOCSIFTXQLEN, (void *) &ifr) < 0)
 	{
-		perror("get tap hwaddr");
-		exit( -1);
+		LOG(0, 0, 0, "Error setting tun queue length: %s\n", strerror(errno));
+		exit(1);
 	}
-	memcpy(&tapmac, 2 + (u8 *) & ifr.ifr_hwaddr, 6);
-	if (ioctl(ifrfd, SIOCGIFINDEX, (void *) &ifr) < 0)
+	ifr.ifr_flags = IFF_UP;
+	if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0)
 	{
-		perror("get tap ifindex");
-		exit( -1);
+		LOG(0, 0, 0, "Error setting tun flags: %s\n", strerror(errno));
+		exit(1);
 	}
-	tapidx = ifr.ifr_ifindex;
 }
 
 // set up UDP port
-void initudp(void)
+static void initudp(void)
 {
 	int on = 1;
 	struct sockaddr_in addr;
@@ -334,48 +416,81 @@ void initudp(void)
 	addr.sin_family = AF_INET;
 	addr.sin_port = htons(L2TPPORT);
 	addr.sin_addr.s_addr = config->bind_address;
-	udpfd = socket(AF_INET, SOCK_DGRAM, UDP);
+	udpfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
 	setsockopt(udpfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
+	{
+		int flags = fcntl(udpfd, F_GETFL, 0);
+		fcntl(udpfd, F_SETFL, flags | O_NONBLOCK);
+	}
 	if (bind(udpfd, (void *) &addr, sizeof(addr)) < 0)
 	{
-		perror("udp bind");
-		exit( -1);
+		LOG(0, 0, 0, "Error in UDP bind: %s\n", strerror(errno));
+		exit(1);
 	}
-	snoopfd = socket(AF_INET, SOCK_DGRAM, UDP);
+	snoopfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
 
 	// Control
 	memset(&addr, 0, sizeof(addr));
 	addr.sin_family = AF_INET;
-	addr.sin_port = htons(1702);
-	controlfd = socket(AF_INET, SOCK_DGRAM, 17);
+	addr.sin_port = htons(NSCTL_PORT);
+	controlfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
 	setsockopt(controlfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
 	if (bind(controlfd, (void *) &addr, sizeof(addr)) < 0)
 	{
-		perror("bind");
-		exit(-1);
+		LOG(0, 0, 0, "Error in control bind: %s\n", strerror(errno));
+		exit(1);
 	}
 }
 
-// Find session by IP, 0 for not found
-sessionidt sessionbyip(ipt ip)
+//
+// Find session by IP, < 1 for not found
+//
+// Confusingly enough, this 'ip' must be
+// in _network_ order. This being the common
+// case when looking it up from IP packet headers.
+//
+// We actually use this cache for two things.
+// #1. For used IP addresses, this maps to the
+// session ID that it's used by.
+// #2. For un-used IP addresses, this maps to the
+// index into the pool table that contains that
+// IP address.
+//
+
+static int lookup_ipmap(ipt ip)
 {
-	unsigned char *a = (unsigned char *)&ip;
+	u8 *a = (u8 *)&ip;
 	char **d = (char **) ip_hash;
-
-#ifdef STAT_CALLS
-	STAT(call_sessionbyip);
-#endif
+	int s;
 
 	if (!(d = (char **) d[(size_t) *a++])) return 0;
 	if (!(d = (char **) d[(size_t) *a++])) return 0;
 	if (!(d = (char **) d[(size_t) *a++])) return 0;
 
-	return (ipt) d[(size_t) *a];
+	s = (ipt) d[(size_t) *a];
+	return s;
+}
+
+sessionidt sessionbyip(ipt ip)
+{
+	int s = lookup_ipmap(ip);
+	CSTAT(call_sessionbyip);
+
+	if (s > 0 && s < MAXSESSION && session[s].tunnel)
+		return s;
+	return 0;
 }
 
-void cache_sessionid(ipt ip, sessionidt s)
+//
+// Take an IP address in HOST byte order and
+// add it to the sessionid by IP cache.
+//
+// (It's actually cached in network order)
+//
+static void cache_ipmap(ipt ip, int s)
 {
-	unsigned char *a = (unsigned char *) &ip;
+	ipt nip = htonl(ip);		// MUST be in network order. I.e. MSB must in be ((char*)(&ip))[0]
+	u8 *a = (u8 *) &nip;
 	char **d = (char **) ip_hash;
 	int i;
 
@@ -390,187 +505,158 @@ void cache_sessionid(ipt ip, sessionidt s)
 		d = (char **) d[(size_t) a[i]];
 	}
 
-	log(4, ip, s, session[s].tunnel, "Caching session ID %d for ip address\n", s);
 	d[(size_t) a[3]] = (char *)((int)s);
+
+	if (s > 0)
+		LOG(4, s, session[s].tunnel, "Caching ip address %s\n", fmtaddr(nip, 0));
+
+	else if (s == 0)
+		LOG(4, 0, 0, "Un-caching ip address %s\n", fmtaddr(nip, 0));
+	// else a map to an ip pool index.
 }
 
-void uncache_sessionid(ipt ip)
+static void uncache_ipmap(ipt ip)
 {
-	unsigned char *a = (unsigned char *) &ip;
-	char **d = (char **) ip_hash;
-	int i;
+	cache_ipmap(ip, 0);	// Assign it to the NULL session.
+}
 
-	for (i = 0; i < 3; i++)
+//
+// CLI list to dump current ipcache.
+//
+int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc)
+{
+	char **d = (char **) ip_hash, **e, **f, **g;
+	int i, j, k, l;
+	int count = 0;
+
+	if (CLI_HELP_REQUESTED)
+		return CLI_HELP_NO_ARGS;
+
+	cli_print(cli, "%7s %s", "Sess#", "IP Address");
+
+	for (i = 0; i < 256; ++i)
 	{
-		if (!d[(size_t) a[i]]) return;
-		d = (char **) d[(size_t) a[i]];
+		if (!d[i])
+			continue;
+		e = (char**) d[i];
+		for (j = 0; j < 256; ++j)
+		{
+			if (!e[j])
+				continue;
+			f = (char**) e[j];
+			for (k = 0; k < 256; ++k)
+			{
+				if (!f[k])
+					continue;
+				g = (char**)f[k];
+				for (l = 0; l < 256; ++l)
+				{
+					if (!g[l])
+						continue;
+					cli_print(cli, "%7d %d.%d.%d.%d", (int) g[l], i, j, k, l);
+					++count;
+				}
+			}
+		}
 	}
-	d[(size_t) a[3]] = NULL;
+	cli_print(cli, "%d entries in cache", count);
+	return CLI_OK;
 }
 
+
 // Find session by username, 0 for not found
 // walled garden users aren't authenticated, so the username is
 // reasonably useless. Ignore them to avoid incorrect actions
+//
+// This is VERY inefficent. Don't call it often. :)
+//
 sessionidt sessionbyuser(char *username)
 {
 	int s;
-#ifdef STAT_CALLS
-	STAT(call_sessionbyuser);
-#endif
-	for (s = 1; s < MAXSESSION && (session[s].walled_garden || strncmp(session[s].user, username, 128)); s++);
-	if (s < MAXSESSION)
-		return s;
-	return 0;
+	CSTAT(call_sessionbyuser);
+
+	for (s = 1; s < MAXSESSION ; ++s)
+	{
+		if (session[s].walled_garden)
+			continue;		// Skip walled garden users.
+
+		if (!strncmp(session[s].user, username, 128))
+			return s;
+
+	}
+	return 0;	// Not found.
 }
 
 void send_garp(ipt ip)
 {
-    int s;
-    struct ifreq ifr;
-    unsigned char mac[6];
-
-    s = socket(PF_INET, SOCK_DGRAM, 0);
-    if (s < 0)
-    {
-      perror("socket");
-      exit(-1);
-    }
-    memset(&ifr, 0, sizeof(ifr));
-    strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
-    if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
-    {
-      perror("get eth0 hwaddr");
-      exit(-1);
-    }
-    memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
-    if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
-    {
-      perror("get eth0 ifindex");
-      exit(-1);
-    }
-    close(s);
-    sendarp(ifr.ifr_ifindex, mac, ip);
+	int s;
+	struct ifreq ifr;
+	u8 mac[6];
+
+	s = socket(PF_INET, SOCK_DGRAM, 0);
+	if (s < 0)
+	{
+		LOG(0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
+		return;
+	}
+	memset(&ifr, 0, sizeof(ifr));
+	strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
+	if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
+	{
+		LOG(0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
+		close(s);
+		return;
+	}
+	memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
+	if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
+	{
+		LOG(0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
+		close(s);
+		return;
+	}
+	close(s);
+	sendarp(ifr.ifr_ifindex, mac, ip);
 }
 
 // Find session by username, 0 for not found
-sessiont *sessiontbysessionidt(sessionidt s)
+static sessiont *sessiontbysessionidt(sessionidt s)
 {
 	if (!s || s > MAXSESSION) return NULL;
 	return &session[s];
 }
 
-sessionidt sessionidtbysessiont(sessiont *s)
+static sessionidt sessionidtbysessiont(sessiont *s)
 {
 	sessionidt val = s-session;
 	if (s < session || val > MAXSESSION) return 0;
 	return val;
 }
 
-// send gratuitous ARP to set ARP table for newly allocated IP
-void sessionsendarp(sessionidt s)
+// actually send a control message for a specific tunnel
+void tunnelsend(u8 * buf, u16 l, tunnelidt t)
 {
-        unsigned char mac[6];
-#ifdef STAT_CALLS
-	STAT(call_sendarp);
-#endif
-	*(u16 *) (mac + 0) = htons(tapmac[0]); // set source address
-	*(u16 *) (mac + 2) = htons(tapmac[1]);
-	*(u16 *) (mac + 4) = htons(tapmac[2]);
-	sendarp(tapidx, mac, session[s].ip);
-	STAT(arp_sent);
-}
+	struct sockaddr_in addr;
 
-// Handle ARP requests
-void processarp(u8 * buf, int len)
-{
-	ipt ip;
-	sessionidt s;
+	CSTAT(call_tunnelsend);
 
-#ifdef STAT_CALLS
-	STAT(call_processarp);
-#endif
-	STAT(arp_recv);
-	if (len != 46)
-	{
-		log(0, 0, 0, 0, "Unexpected length ARP %d bytes\n", len);
-		STAT(arp_errors);
-		return;
-	}
-	if (*(u16 *) (buf + 16) != htons(PKTARP))
-	{
-		log(0, 0, 0, 0, "Unexpected ARP type %04X\n", ntohs(*(u16 *) (buf + 16)));
-		STAT(arp_errors);
-		return;
-	}
-	if (*(u16 *) (buf + 18) != htons(0x0001))
-	{
-		log(0, 0, 0, 0, "Unexpected ARP hard type %04X\n", ntohs(*(u16 *) (buf + 18)));
-		STAT(arp_errors);
-		return;
-	}
-	if (*(u16 *) (buf + 20) != htons(PKTIP))
-	{
-		log(0, 0, 0, 0, "Unexpected ARP prot type %04X\n", ntohs(*(u16 *) (buf + 20)));
-		STAT(arp_errors);
-		return;
-	}
-	if (buf[22] != 6)
-	{
-		log(0, 0, 0, 0, "Unexpected ARP hard len %d\n", buf[22]);
-		STAT(arp_errors);
-		return;
-	}
-	if (buf[23] != 4)
-	{
-		log(0, 0, 0, 0, "Unexpected ARP prot len %d\n", buf[23]);
-		STAT(arp_errors);
-		return;
-	}
-	if (*(u16 *) (buf + 24) != htons(0x0001))
+	if (!t)
 	{
-		log(0, 0, 0, 0, "Unexpected ARP op %04X\n", ntohs(*(u16 *) (buf + 24)));
-		STAT(arp_errors);
+		static int backtrace_count = 0;
+		LOG(0, 0, t, "tunnelsend called with 0 as tunnel id\n");
+		STAT(tunnel_tx_errors);
+		log_backtrace(backtrace_count, 5)
 		return;
 	}
-	ip = ntohl(*(u32 *) (buf + 42));
-	// look up session
-	s = sessionbyip(htonl(ip));
-	if (s)
-	{
-		log(3, ip, s, session[s].tunnel, "ARP reply for %u.%u.%u.%u\n", ip >> 24, ip >> 16 & 255, ip >> 8 & 255, ip & 255, session[s].tunnel, s);
-		memcpy(buf + 4, buf + 10, 6); // set destination as source
-		*(u16 *) (buf + 10) = htons(tapmac[0]); // set soucre address
-		*(u16 *) (buf + 12) = htons(tapmac[1]);
-		*(u16 *) (buf + 14) = htons(tapmac[2]);
-		*(u16 *) (buf + 24) = htons(0x0002); // ARP reply
-		memcpy(buf + 26, buf + 10, 6); // sender ethernet
-		memcpy(buf + 36, buf + 4, 6); // target ethernet
-		*(u32 *) (buf + 42) = *(u32 *) (buf + 32); // target IP
-		*(u32 *) (buf + 32) = htonl(ip); // sender IP
-		write(tapfd, buf, len);
-		STAT(arp_replies);
-	}
-	else
-	{
-		log(3, ip, 0, 0, "ARP request for unknown IP %u.%u.%u.%u\n", ip >> 24, ip >> 16 & 255, ip >> 8 & 255, ip & 255);
-		STAT(arp_discarded);
-	}
-}
 
-// actually send a control message for a specific tunnel
-void tunnelsend(u8 * buf, u16 l, tunnelidt t)
-{
-	struct sockaddr_in addr;
-
-#ifdef STAT_CALLS
-	STAT(call_tunnelsend);
-#endif
 	if (!tunnel[t].ip)
 	{
-		log(1, 0, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
+		static int backtrace_count = 0;
+		LOG(1, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
+		log_backtrace(backtrace_count, 5)
 		STAT(tunnel_tx_errors);
 		return;
 	}
+
 	memset(&addr, 0, sizeof(addr));
 	addr.sin_family = AF_INET;
 	*(u32 *) & addr.sin_addr = htonl(tunnel[t].ip);
@@ -587,37 +673,57 @@ void tunnelsend(u8 * buf, u16 l, tunnelidt t)
 		if (tunnel[t].try > 1)
 		{
 			STAT(tunnel_retries);
-			log(3, tunnel[t].ip, 0, t, "Control message resend try %d\n", tunnel[t].try);
+			LOG(3, 0, t, "Control message resend try %d\n", tunnel[t].try);
 		}
 	}
 
 	if (sendto(udpfd, buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
 	{
-		log(0, tunnel[t].ip, ntohs((*(u16 *) (buf + 6))), t, "Error sending data out tunnel: %s (udpfd=%d, buf=%p, len=%d, dest=%s)\n",
+		LOG(0, ntohs((*(u16 *) (buf + 6))), t, "Error sending data out tunnel: %s (udpfd=%d, buf=%p, len=%d, dest=%s)\n",
 				strerror(errno), udpfd, buf, l, inet_ntoa(addr.sin_addr));
 		STAT(tunnel_tx_errors);
 		return;
 	}
 
-	log_hex(5, "Send Tunnel Data", buf, l);
+	LOG_HEX(5, "Send Tunnel Data", buf, l);
 	STAT(tunnel_tx_packets);
 	INC_STAT(tunnel_tx_bytes, l);
 }
 
+//
+// Tiny helper function to write data to
+// the 'tun' device.
+//
+int tun_write(u8 * data, int size)
+{
+	return write(tunfd, data, size);
+}
+
 // process outgoing (to tunnel) IP
-void processipout(u8 * buf, int len)
+//
+static void processipout(u8 * buf, int len)
 {
 	sessionidt s;
 	sessiont *sp;
 	tunnelidt t;
 	ipt ip;
-	u8 b[MAXETHER];
-#ifdef STAT_CALLS
-	STAT(call_processipout);
-#endif
-	if (len < 38)
+
+	char * data = buf;	// Keep a copy of the originals.
+	int size = len;
+
+	u8 b[MAXETHER + 20];
+
+	CSTAT(call_processipout);
+
+	if (len < MIN_IP_SIZE)
+	{
+		LOG(1, 0, 0, "Short IP, %d bytes\n", len);
+		STAT(tunnel_tx_errors);
+		return;
+	}
+	if (len >= MAXETHER)
 	{
-		log(1, 0, 0, 0, "Short IP, %d bytes\n", len);
+		LOG(1, 0, 0, "Oversize IP packet %d bytes\n", len);
 		STAT(tunnel_tx_errors);
 		return;
 	}
@@ -629,44 +735,125 @@ void processipout(u8 * buf, int len)
 	// Got an IP header now
 	if (*(u8 *)(buf) >> 4 != 4)
 	{
-		log(1, 0, 0, 0, "IP: Don't understand anything except IPv4\n");
+		LOG(1, 0, 0, "IP: Don't understand anything except IPv4\n");
 		return;
 	}
 
 	ip = *(u32 *)(buf + 16);
 	if (!(s = sessionbyip(ip)))
 	{
-		log(4, 0, 0, 0, "IP: Sending ICMP host unreachable to %s\n", inet_toa(*(u32 *)(buf + 12)));
-		host_unreachable(*(u32 *)(buf + 12), *(u16 *)(buf + 4), ip, buf, (len < 64) ? 64 : len);
+		// 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.
+		{
+			LOG(4, 0, 0, "IP: Sending ICMP host unreachable to %s\n", fmtaddr(*(u32 *)(buf + 12), 0));
+			host_unreachable(*(u32 *)(buf + 12), *(u16 *)(buf + 4), ip, buf, (len < 64) ? 64 : len);
+		}
 		return;
 	}
 	t = session[s].tunnel;
 	sp = &session[s];
 
-	// Snooping this session, send it to ASIO
-	if (sp->snoop) snoop_send_packet(buf, len);
+	// run access-list if any
+	if (session[s].filter_out && !ip_filter(buf, len, session[s].filter_out - 1))
+		return;
+
+	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
+	{
+		u8 *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
+		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_count[s].cout += len;	// To send to master..
+}
+
+//
+// Helper routine for the TBF filters.
+// Used to send queued data in to the user!
+//
+static void send_ipout(sessionidt s, u8 *buf, int len)
+{
+	sessiont *sp;
+	tunnelidt t;
+	ipt ip;
 
-	log(5, session[s].ip, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
+	u8 b[MAXETHER + 20];
 
-	// Plugin hook
+	if (len < 0 || len > MAXETHER)
 	{
-		struct param_packet_rx packet = { &tunnel[t], &session[s], buf, len };
-		run_plugins(PLUGIN_PACKET_RX, &packet);
+		LOG(1, 0, 0, "Odd size IP packet: %d bytes\n", len);
+		return;
 	}
 
+	// Skip the tun header
+	buf += 4;
+	len -= 4;
+
+	ip = *(u32 *)(buf + 16);
+
+	if (!session[s].ip)
+		return;
+
+	t = session[s].tunnel;
+	sp = &session[s];
+
+	LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
+
 	// Add on L2TP header
 	{
-		u8 *p = makeppp(b, buf, len, t, s, PPPIP);
+		u8 *p = makeppp(b, sizeof(b),  buf, len, t, s, PPPIP);
+		if (!p) return;
 		tunnelsend(b, len + (p-b), t); // send it...
-		sp->cout += len; // byte count
-		sp->total_cout += len; // byte count
-		sp->pout++;
-		udp_tx += len;
 	}
+
+	// Snooping this session.
+	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_count[s].cout += len;	// To send to master..
 }
 
 // add an AVP (16 bit)
-void control16(controlt * c, u16 avp, u16 val, u8 m)
+static void control16(controlt * c, u16 avp, u16 val, u8 m)
 {
 	u16 l = (m ? 0x8008 : 0x0008);
 	*(u16 *) (c->buf + c->length + 0) = htons(l);
@@ -677,7 +864,7 @@ void control16(controlt * c, u16 avp, u16 val, u8 m)
 }
 
 // add an AVP (32 bit)
-void control32(controlt * c, u16 avp, u32 val, u8 m)
+static void control32(controlt * c, u16 avp, u32 val, u8 m)
 {
 	u16 l = (m ? 0x800A : 0x000A);
 	*(u16 *) (c->buf + c->length + 0) = htons(l);
@@ -688,7 +875,7 @@ void control32(controlt * c, u16 avp, u32 val, u8 m)
 }
 
 // add an AVP (32 bit)
-void controls(controlt * c, u16 avp, char *val, u8 m)
+static void controls(controlt * c, u16 avp, char *val, u8 m)
 {
 	u16 l = ((m ? 0x8000 : 0) + strlen(val) + 6);
 	*(u16 *) (c->buf + c->length + 0) = htons(l);
@@ -699,7 +886,7 @@ void controls(controlt * c, u16 avp, char *val, u8 m)
 }
 
 // add a binary AVP
-void controlb(controlt * c, u16 avp, char *val, unsigned int len, u8 m)
+static void controlb(controlt * c, u16 avp, char *val, unsigned int len, u8 m)
 {
 	u16 l = ((m ? 0x8000 : 0) + len + 6);
 	*(u16 *) (c->buf + c->length + 0) = htons(l);
@@ -710,7 +897,7 @@ void controlb(controlt * c, u16 avp, char *val, unsigned int len, u8 m)
 }
 
 // new control connection
-controlt *controlnew(u16 mtype)
+static controlt *controlnew(u16 mtype)
 {
 	controlt *c;
 	if (!controlfree)
@@ -729,11 +916,13 @@ controlt *controlnew(u16 mtype)
 }
 
 // send zero block if nothing is waiting
-void controlnull(tunnelidt t)
+// (ZLB send).
+static void controlnull(tunnelidt t)
 {
 	u8 buf[12];
-	if (tunnel[t].controlc)
+	if (tunnel[t].controlc)	// Messages queued; They will carry the ack.
 		return;
+
 	*(u16 *) (buf + 0) = htons(0xC802); // flags/ver
 	*(u16 *) (buf + 2) = htons(12); // length
 	*(u16 *) (buf + 4) = htons(tunnel[t].far); // tunnel
@@ -744,7 +933,7 @@ void controlnull(tunnelidt t)
 }
 
 // add a control message to a tunnel, and send if within window
-void controladd(controlt * c, tunnelidt t, sessionidt s)
+static void controladd(controlt * c, tunnelidt t, sessionidt s)
 {
 	*(u16 *) (c->buf + 2) = htons(c->length); // length
 	*(u16 *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
@@ -756,8 +945,10 @@ void controladd(controlt * c, tunnelidt t, sessionidt s)
 		tunnel[t].controle->next = c;
 	else
 		tunnel[t].controls = c;
+
 	tunnel[t].controle = c;
 	tunnel[t].controlc++;
+
 	// send now if space in window
 	if (tunnel[t].controlc <= tunnel[t].window)
 	{
@@ -766,36 +957,121 @@ void controladd(controlt * c, tunnelidt t, sessionidt s)
 	}
 }
 
+//
+// Throttle or Unthrottle a session
+//
+// Throttle the data from/to through a session to no more than
+// 'rate_in' kbit/sec in (from user) or 'rate_out' kbit/sec out (to
+// user).
+//
+// If either value is -1, the current value is retained for that
+// direction.
+//
+void throttle_session(sessionidt s, int rate_in, int rate_out)
+{
+	if (!session[s].tunnel)
+		return; // No-one home.
+
+	if (!*session[s].user)
+	        return; // User not logged in
+
+	if (rate_in >= 0)
+	{
+		int bytes = rate_in * 1024 / 8; // kbits to bytes
+		if (session[s].tbf_in)
+			free_tbf(session[s].tbf_in);
+
+		if (rate_in > 0)
+			session[s].tbf_in = new_tbf(s, bytes * 2, bytes, send_ipin);
+		else
+			session[s].tbf_in = 0;
+
+		session[s].throttle_in = rate_in;
+	}
+
+	if (rate_out >= 0)
+	{
+		int bytes = rate_out * 1024 / 8;
+		if (session[s].tbf_out)
+			free_tbf(session[s].tbf_out);
+
+		if (rate_out > 0)
+			session[s].tbf_out = new_tbf(s, bytes * 2, bytes, send_ipout);
+		else
+			session[s].tbf_out = 0;
+
+		session[s].throttle_out = rate_out;
+	}
+}
+
+// add/remove filters from session (-1 = no change)
+void filter_session(sessionidt s, int filter_in, int filter_out)
+{
+	if (!session[s].tunnel)
+		return; // No-one home.
+
+	if (!*session[s].user)
+	        return; // User not logged in
+
+	// paranoia
+	if (filter_in > MAXFILTER) filter_in = -1;
+	if (filter_out > MAXFILTER) filter_out = -1;
+	if (session[s].filter_in > MAXFILTER) session[s].filter_in = 0;
+	if (session[s].filter_out > MAXFILTER) session[s].filter_out = 0;
+
+	if (filter_in >= 0)
+	{
+		if (session[s].filter_in)
+			ip_filters[session[s].filter_in - 1].used--;
+
+		if (filter_in > 0)
+			ip_filters[filter_in - 1].used++;
+
+		session[s].filter_in = filter_in;
+	}
+
+	if (filter_out >= 0)
+	{
+		if (session[s].filter_out)
+			ip_filters[session[s].filter_out - 1].used--;
+
+		if (filter_out > 0)
+			ip_filters[filter_out - 1].used++;
+
+		session[s].filter_out = filter_out;
+	}
+}
+
 // start tidy shutdown of session
 void sessionshutdown(sessionidt s, char *reason)
 {
-	int dead = session[s].die;
 	int walled_garden = session[s].walled_garden;
 
-#ifdef STAT_CALLS
-	STAT(call_sessionshutdown);
-#endif
+
+	CSTAT(call_sessionshutdown);
+
 	if (!session[s].tunnel)
+	{
+		LOG(3, s, session[s].tunnel, "Called sessionshutdown on a session with no tunnel.\n");
 		return;                   // not a live session
+	}
 
 	if (!session[s].die)
-		log(2, 0, s, session[s].tunnel, "Shutting down session %d: %s\n", s, reason);
-
-	session[s].die = now() + 150; // Clean up in 15 seconds
-
 	{
 		struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
+		LOG(2, s, session[s].tunnel, "Shutting down session %d: %s\n", s, reason);
 		run_plugins(PLUGIN_KILL_SESSION, &data);
 	}
 
 	// RADIUS Stop message
-	if (session[s].opened && !walled_garden && !dead) {
-		u8 r = session[s].radius;
+	if (session[s].opened && !walled_garden && !session[s].die)
+	{
+		u16 r = session[s].radius;
 		if (!r)
 		{
 			if (!(r = radiusnew(s)))
 			{
-				log(1, 0, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
+				LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
 				STAT(radius_overflow);
 			}
 			else
@@ -811,86 +1087,123 @@ void sessionshutdown(sessionidt s, char *reason)
 
 	if (session[s].ip)
 	{                          // IP allocated, clear and unroute
-		u8 r;
-		if (session[s].route[0].ip)
+		int r;
+		int routed = 0;
+		for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
 		{
-			routeset(session[s].ip, 0, 0, 0);
-			for (r = 0; r < MAXROUTE; r++)
-			{
-				if (session[s].route[r].ip)
-				{
-					routeset(session[s].route[r].ip, session[s].route[r].mask, session[s].ip, 0);
-					session[s].route[r].ip = 0;
-				}
-			}
+			if ((session[s].ip & session[s].route[r].mask) ==
+			    (session[s].route[r].ip & session[s].route[r].mask))
+				routed++;
+
+			routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 0);
+			session[s].route[r].ip = 0;
+		}
+
+		if (session[s].ip_pool_index == -1) // static ip
+		{
+			if (!routed) routeset(s, session[s].ip, 0, 0, 0);
+			session[s].ip = 0;
 		}
-		if (session[s].throttle) throttle_session(s, 0); session[s].throttle = 0;
-		free_ip_address(s);
+		else
+			free_ip_address(s);
 	}
+
+	if (session[s].throttle_in || session[s].throttle_out) // Unthrottle if throttled.
+		throttle_session(s, 0, 0);
+
 	{                            // Send CDN
 		controlt *c = controlnew(14); // sending CDN
 		control16(c, 1, 3, 1);    // result code (admin reasons - TBA make error, general error, add message
 		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
+
+	// update filter refcounts
+	if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
+	if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
+
 	cluster_send_session(s);
 }
 
 void sendipcp(tunnelidt t, sessionidt s)
 {
 	u8 buf[MAXCONTROL];
-	u8 r = session[s].radius;
+	u16 r = session[s].radius;
 	u8 *q;
-#ifdef STAT_CALLS
-	STAT(call_sendipcp);
-#endif
+
+	CSTAT(call_sendipcp);
+
 	if (!r)
 		r = radiusnew(s);
+
 	if (radius[r].state != RADIUSIPCP)
 	{
 		radius[r].state = RADIUSIPCP;
 		radius[r].try = 0;
 	}
+
 	radius[r].retry = backoff(radius[r].try++);
 	if (radius[r].try > 10)
 	{
+		radiusclear(r, s);	// Clear radius session.
 		sessionshutdown(s, "No reply on IPCP");
 		return;
 	}
-	q = makeppp(buf, 0, 0, t, s, PPPIPCP);
+
+	q = makeppp(buf,sizeof(buf), 0, 0, t, s, PPPIPCP);
+	if (!q) return;
+
 	*q = ConfigReq;
-	q[1] = r;                    // ID, dont care, we only send one type of request
+	q[1] = r << RADIUS_SHIFT;                    // ID, dont care, we only send one type of request
 	*(u16 *) (q + 2) = htons(10);
 	q[4] = 3;
 	q[5] = 6;
-	*(u32 *) (q + 6) = htonl(myip ? myip : session[s].ip); // send my IP (use theirs if I dont have one)
+	*(u32 *) (q + 6) = config->peer_address ? config->peer_address :
+	    		   config->bind_address ? config->bind_address :
+			   my_address; // send my IP
+
 	tunnelsend(buf, 10 + (q - buf), t); // send it
+	session[s].flags &= ~SF_IPCP_ACKED;	// Clear flag.
 }
 
 // kill a session now
-void sessionkill(sessionidt s, char *reason)
+static void sessionkill(sessionidt s, char *reason)
 {
-#ifdef STAT_CALLS
-	STAT(call_sessionkill);
-#endif
+
+	CSTAT(call_sessionkill);
+
+	session[s].die = now();
 	sessionshutdown(s, reason);  // close radius/routes, etc.
 	if (session[s].radius)
-		radiusclear(session[s].radius, 0); // cant send clean accounting data, session is killed
+		radiusclear(session[s].radius, s); // cant send clean accounting data, session is killed
+
+	LOG(2, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
+
 	memset(&session[s], 0, sizeof(session[s]));
+	session[s].tunnel = T_FREE;	// Mark it as free.
 	session[s].next = sessionfree;
 	sessionfree = s;
-	log(2, 0, s, session[s].tunnel, "Kill session %d: %s\n", s, reason);
+	cli_session_actions[s].action = 0;
 	cluster_send_session(s);
 }
 
+static void tunnelclear(tunnelidt t)
+{
+	if (!t) return;
+	memset(&tunnel[t], 0, sizeof(tunnel[t]));
+	tunnel[t].state = TUNNELFREE;
+}
+
 // kill a tunnel now
-void tunnelkill(tunnelidt t, char *reason)
+static void tunnelkill(tunnelidt t, char *reason)
 {
 	sessionidt s;
 	controlt *c;
-#ifdef STAT_CALLS
-	STAT(call_tunnelkill);
-#endif
+
+	CSTAT(call_tunnelkill);
 
 	tunnel[t].state = TUNNELDIE;
 
@@ -910,31 +1223,30 @@ void tunnelkill(tunnelidt t, char *reason)
 
 	// free tunnel
 	tunnelclear(t);
+	LOG(1, 0, t, "Kill tunnel %d: %s\n", t, reason);
+	cli_tunnel_actions[s].action = 0;
 	cluster_send_tunnel(t);
-	log(1, 0, 0, t, "Kill tunnel %d: %s\n", t, reason);
-	tunnel[t].die = 0;
-	tunnel[t].state = TUNNELFREE;
 }
 
 // shut down a tunnel cleanly
-void tunnelshutdown(tunnelidt t, char *reason)
+static void tunnelshutdown(tunnelidt t, char *reason)
 {
 	sessionidt s;
-#ifdef STAT_CALLS
-	STAT(call_tunnelshutdown);
-#endif
+
+	CSTAT(call_tunnelshutdown);
+
 	if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
 	{
 		// never set up, can immediately kill
 		tunnelkill(t, reason);
 		return;
 	}
-	log(1, 0, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
+	LOG(1, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
 
 	// close session
 	for (s = 1; s < MAXSESSION; s++)
 		if (session[s].tunnel == t)
-			sessionkill(s, reason);
+			sessionshutdown(s, reason);
 
 	tunnel[t].state = TUNNELDIE;
 	tunnel[t].die = now() + 700; // Clean up in 70 seconds
@@ -955,23 +1267,23 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 	u16 l = len, t = 0, s = 0, ns = 0, nr = 0;
 	u8 *p = buf + 2;
 
-#ifdef STAT_CALLS
-	STAT(call_processudp);
-#endif
+
+	CSTAT(call_processudp);
+
 	udp_rx += len;
 	udp_rx_pkt++;
-	log_hex(5, "UDP Data", buf, len);
+	LOG_HEX(5, "UDP Data", buf, len);
 	STAT(tunnel_rx_packets);
 	INC_STAT(tunnel_rx_bytes, len);
 	if (len < 6)
 	{
-		log(1, ntohl(addr->sin_addr.s_addr), 0, 0, "Short UDP, %d bytes\n", len);
+		LOG(1, 0, 0, "Short UDP, %d bytes\n", len);
 		STAT(tunnel_rx_errors);
 		return;
 	}
 	if ((buf[1] & 0x0F) != 2)
 	{
-		log(1, ntohl(addr->sin_addr.s_addr), 0, 0, "Bad L2TP ver %d\n", (buf[1] & 0x0F) != 2);
+		LOG(1, 0, 0, "Bad L2TP ver %d\n", (buf[1] & 0x0F) != 2);
 		STAT(tunnel_rx_errors);
 		return;
 	}
@@ -986,19 +1298,13 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 	p += 2;
 	if (s >= MAXSESSION)
 	{
-		log(1, ntohl(addr->sin_addr.s_addr), s, t, "Received UDP packet with invalid session ID\n");
+		LOG(1, s, t, "Received UDP packet with invalid session ID\n");
 		STAT(tunnel_rx_errors);
 		return;
 	}
 	if (t >= MAXTUNNEL)
 	{
-		log(1, ntohl(addr->sin_addr.s_addr), s, t, "Received UDP packet with invalid tunnel ID\n");
-		STAT(tunnel_rx_errors);
-		return;
-	}
-	if (s && !session[s].tunnel)
-	{
-		log(1, ntohl(addr->sin_addr.s_addr), 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, "Received UDP packet with invalid tunnel ID\n");
 		STAT(tunnel_rx_errors);
 		return;
 	}
@@ -1016,7 +1322,7 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 	}
 	if ((p - buf) > l)
 	{
-		log(1, ntohl(addr->sin_addr.s_addr), s, t, "Bad length %d>%d\n", (p - buf), l);
+		LOG(1, s, t, "Bad length %d>%d\n", (p - buf), l);
 		STAT(tunnel_rx_errors);
 		return;
 	}
@@ -1034,20 +1340,49 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 		int requestchap = 0;	// do we request PAP instead of original CHAP request?
 		char called[MAXTEL] = ""; // called number
 		char calling[MAXTEL] = ""; // calling number
+
+		if (!config->cluster_iam_master)
+		{
+			master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
+			return;
+		}
+
 		if ((*buf & 0xCA) != 0xC8)
 		{
-			log(1, ntohl(addr->sin_addr.s_addr), s, t, "Bad control header %02X\n", *buf);
+			LOG(1, s, t, "Bad control header %02X\n", *buf);
 			STAT(tunnel_rx_errors);
 			return;
 		}
-		log(3, ntohl(addr->sin_addr.s_addr), s, t, "Control message (%d bytes): %d ns %d nr %d ns %d nr %d\n",
-				l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
+
+		// check for duplicate tunnel open message
+		if (!t && ns == 0)
+		{
+			int i;
+
+				//
+				// Is this a duplicate of the first packet? (SCCRQ)
+				//
+			for (i = 1; i <= config->cluster_highest_tunnelid ; ++i)
+			{
+				if (tunnel[i].state != TUNNELOPENING ||
+					tunnel[i].ip != ntohl(*(ipt *) & addr->sin_addr) ||
+					tunnel[i].port != ntohs(addr->sin_port) )
+					continue;
+				t = i;
+				LOG(3, s, t, "Duplicate SCCRQ?\n");
+				break;
+			}
+		}
+
+		LOG(3, s, t, "Control message (%d bytes): (unacked %d) l-ns %d l-nr %d r-ns %d r-nr %d\n",
+			l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
+
 		// if no tunnel specified, assign one
 		if (!t)
 		{
 			if (!(t = new_tunnel()))
 			{
-				log(1, ntohl(addr->sin_addr.s_addr), 0, 0, "No more tunnels\n");
+				LOG(1, 0, 0, "No more tunnels\n");
 				STAT(tunnel_overflow);
 				return;
 			}
@@ -1055,8 +1390,27 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 			tunnel[t].ip = ntohl(*(ipt *) & addr->sin_addr);
 			tunnel[t].port = ntohs(addr->sin_port);
 			tunnel[t].window = 4; // default window
-			log(1, ntohl(addr->sin_addr.s_addr), 0, t, "   New tunnel from %u.%u.%u.%u/%u ID %d\n", tunnel[t].ip >> 24, tunnel[t].ip >> 16 & 255, tunnel[t].ip >> 8 & 255, tunnel[t].ip & 255, tunnel[t].port, t);
 			STAT(tunnel_created);
+			LOG(1, 0, t, "   New tunnel from %s:%u ID %d\n",
+				fmtaddr(htonl(tunnel[t].ip), 0), tunnel[t].port, t);
+		}
+
+			// If the 'ns' just received is not the 'nr' we're
+			// expecting, just send an ack and drop it.
+			//
+			// if 'ns' is less, then we got a retransmitted packet.
+			// if 'ns' is greater than missed a packet. Either way
+			// we should ignore it.
+		if (ns != tunnel[t].nr)
+		{
+			// is this the sequence we were expecting?
+			STAT(tunnel_rx_errors);
+			LOG(1, 0, t, "   Out of sequence tunnel %d, (%d is not the expected %d)\n",
+				t, ns, tunnel[t].nr);
+
+			if (l)	// Is this not a ZLB?
+				controlnull(t);
+			return;
 		}
 
 		// This is used to time out old tunnels
@@ -1065,29 +1419,20 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 		// check sequence of this message
 		{
 			int skip = tunnel[t].window; // track how many in-window packets are still in queue
-			if (tunnel[t].controlc)
-			{                  // some to clear maybe
-				while (tunnel[t].controlc && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
-				{
-					controlt *c = tunnel[t].controls;
-					tunnel[t].controls = c->next;
-					tunnel[t].controlc--;
-					c->next = controlfree;
-					controlfree = c;
-					skip--;
-					tunnel[t].try = 0; // we have progress
-				}
-			}
-			if (tunnel[t].nr < ns && tunnel[t].nr != 0)
+				// some to clear maybe?
+			while (tunnel[t].controlc > 0 && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
 			{
-				// is this the sequence we were expecting?
-				log(1, ntohl(addr->sin_addr.s_addr), 0, t, "   Out of sequence tunnel %d, (%d not %d)\n", t, ns, tunnel[t].nr);
-				STAT(tunnel_rx_errors);
-//				controlnull(t);
-				return;
+				controlt *c = tunnel[t].controls;
+				tunnel[t].controls = c->next;
+				tunnel[t].controlc--;
+				c->next = controlfree;
+				controlfree = c;
+				skip--;
+				tunnel[t].try = 0; // we have progress
 			}
+
 			// receiver advance (do here so quoted correctly in any sends below)
-			if (l) tunnel[t].nr++;
+			if (l) tunnel[t].nr = (ns + 1);
 			if (skip < 0) skip = 0;
 			if (skip < tunnel[t].controlc)
 			{
@@ -1122,7 +1467,7 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 				p += n;       // next
 				if (l < n)
 				{
-					log(1, ntohl(addr->sin_addr.s_addr), s, t, "Invalid length in AVP\n");
+					LOG(1, s, t, "Invalid length in AVP\n");
 					STAT(tunnel_rx_errors);
 					fatal = flags;
 					return;
@@ -1133,28 +1478,35 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 					// handle hidden AVPs
 					if (!*config->l2tpsecret)
 					{
-						log(1, ntohl(addr->sin_addr.s_addr), s, t, "Hidden AVP requested, but no L2TP secret.\n");
+						LOG(1, s, t, "Hidden AVP requested, but no L2TP secret.\n");
 						fatal = flags;
 						continue;
 					}
 					if (!session[s].random_vector_length)
 					{
-						log(1, ntohl(addr->sin_addr.s_addr), s, t, "Hidden AVP requested, but no random vector.\n");
+						LOG(1, s, t, "Hidden AVP requested, but no random vector.\n");
+						fatal = flags;
+						continue;
+					}
+					LOG(4, s, t, "Hidden AVP\n");
+					// Unhide the AVP
+					n = unhide_avp(b, t, s, n);
+					if (n == 0)
+					{
 						fatal = flags;
 						continue;
 					}
-					log(1, ntohl(addr->sin_addr.s_addr), s, t, "Hidden AVP\n");
 				}
 				if (*b & 0x3C)
 				{
-					log(1, ntohl(addr->sin_addr.s_addr), s, t, "Unrecognised AVP flags %02X\n", *b);
+					LOG(1, s, t, "Unrecognised AVP flags %02X\n", *b);
 					fatal = flags;
 					continue; // next
 				}
 				b += 2;
 				if (*(u16 *) (b))
 				{
-					log(2, ntohl(addr->sin_addr.s_addr), s, t, "Unknown AVP vendor %d\n", ntohs(*(u16 *) (b)));
+					LOG(2, s, t, "Unknown AVP vendor %d\n", ntohs(*(u16 *) (b)));
 					fatal = flags;
 					continue; // next
 				}
@@ -1163,124 +1515,127 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 				b += 2;
 				n -= 6;
 
-				log(4, ntohl(addr->sin_addr.s_addr), s, t, "   AVP %d (%s) len %d\n", mtype, avpnames[mtype], n);
+				LOG(4, s, t, "   AVP %d (%s) len %d\n", mtype, avpnames[mtype], n);
 				switch (mtype)
 				{
 				case 0:     // message type
 					message = ntohs(*(u16 *) b);
-					log(4, ntohl(addr->sin_addr.s_addr), s, t, "   Message type = %d (%s)\n", *b,
-							l2tp_message_types[message]);
+					LOG(4, s, t, "   Message type = %d (%s)\n", *b, l2tp_message_types[message]);
 					mandatorymessage = flags;
 					break;
 				case 1:     // result code
 					{
 						u16 rescode = ntohs(*(u16 *)(b));
 						const char* resdesc = "(unknown)";
-						if (message == 4) { /* StopCCN */
+						if (message == 4)
+						{ /* StopCCN */
 							if (rescode <= MAX_STOPCCN_RESULT_CODE)
 								resdesc = stopccn_result_codes[rescode];
-						} else if (message == 14) { /* CDN */
+						}
+						else if (message == 14)
+						{ /* CDN */
 							if (rescode <= MAX_CDN_RESULT_CODE)
 								resdesc = cdn_result_codes[rescode];
 						}
 
-						log(4, ntohl(addr->sin_addr.s_addr), s, t, "   Result Code %d: %s\n",
-							rescode, resdesc);
-						if (n >= 4) {
+						LOG(4, s, t, "   Result Code %d: %s\n", rescode, resdesc);
+						if (n >= 4)
+						{
 							u16 errcode = ntohs(*(u16 *)(b + 2));
 							const char* errdesc = "(unknown)";
 							if (errcode <= MAX_ERROR_CODE)
 								errdesc = error_codes[errcode];
-							log(4, ntohl(addr->sin_addr.s_addr), s, t, "   Error Code %d: %s\n",
-								errcode, errdesc);
-						}
-						if (n > 4) {
-							/* %*s doesn't work?? */
-							char *buf = (char *)strndup(b+4, n-4);
-							log(4, ntohl(addr->sin_addr.s_addr), s, t, "   Error String: %s\n",
-								buf);
-							free(buf);
+							LOG(4, s, t, "   Error Code %d: %s\n", errcode, errdesc);
 						}
+						if (n > 4)
+							LOG(4, s, t, "   Error String: %.*s\n", n-4, b+4);
+
 						break;
 					}
 					break;
 				case 2:     // protocol version
 					{
 						version = ntohs(*(u16 *) (b));
-						log(4, ntohl(addr->sin_addr.s_addr), s, t, "   Protocol version = %d\n", version);
+						LOG(4, s, t, "   Protocol version = %d\n", version);
 						if (version && version != 0x0100)
 						{   // allow 0.0 and 1.0
-							log(1, ntohl(addr->sin_addr.s_addr), s, t, "   Bad protocol version %04X\n",
-									version);
+							LOG(1, s, t, "   Bad protocol version %04X\n", version);
 							fatal = flags;
 							continue; // next
 						}
 					}
 					break;
 				case 3:     // framing capabilities
-//					log(4, ntohl(addr->sin_addr.s_addr), s, t, "Framing capabilities\n");
+//					LOG(4, s, t, "Framing capabilities\n");
 					break;
 				case 4:     // bearer capabilities
-//					log(4, ntohl(addr->sin_addr.s_addr), s, t, "Bearer capabilities\n");
+//					LOG(4, s, t, "Bearer capabilities\n");
 					break;
 				case 5:		// tie breaker
 					// We never open tunnels, so we don't care about tie breakers
-//					log(4, ntohl(addr->sin_addr.s_addr), s, t, "Tie breaker\n");
+//					LOG(4, s, t, "Tie breaker\n");
 					continue;
 				case 6:     // firmware revision
-//					log(4, ntohl(addr->sin_addr.s_addr), s, t, "Firmware revision\n");
+//					LOG(4, s, t, "Firmware revision\n");
 					break;
 				case 7:     // host name
 					memset(tunnel[t].hostname, 0, 128);
 					memcpy(tunnel[t].hostname, b, (n >= 127) ? 127 : n);
-					log(4, ntohl(addr->sin_addr.s_addr), s, t, "   Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
+					LOG(4, s, t, "   Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
 					// TBA - to send to RADIUS
 					break;
 				case 8:     // vendor name
-					memset(tunnel[t].vendor, 0, 128);
-					memcpy(tunnel[t].vendor, b, (n >= 127) ? 127 : n);
-					log(4, ntohl(addr->sin_addr.s_addr), s, t, "   Vendor name = \"%s\"\n", tunnel[t].vendor);
+					memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
+					memcpy(tunnel[t].vendor, b, (n >= sizeof(tunnel[t].vendor) - 1) ? sizeof(tunnel[t].vendor) - 1 : n);
+					LOG(4, s, t, "   Vendor name = \"%s\"\n", tunnel[t].vendor);
 					break;
 				case 9:     // assigned tunnel
 					tunnel[t].far = ntohs(*(u16 *) (b));
-					log(4, ntohl(addr->sin_addr.s_addr), s, t, "   Remote tunnel id = %d\n", tunnel[t].far);
+					LOG(4, s, t, "   Remote tunnel id = %d\n", tunnel[t].far);
 					break;
 				case 10:    // rx window
 					tunnel[t].window = ntohs(*(u16 *) (b));
 					if (!tunnel[t].window)
 						tunnel[t].window = 1; // window of 0 is silly
-					log(4, ntohl(addr->sin_addr.s_addr), s, t, "   rx window = %d\n", tunnel[t].window);
+					LOG(4, s, t, "   rx window = %d\n", tunnel[t].window);
 					break;
 				case 11:	// Challenge
 					{
-						log(4, ntohl(addr->sin_addr.s_addr), s, t, "   LAC requested CHAP authentication for tunnel\n");
+						LOG(4, s, t, "   LAC requested CHAP authentication for tunnel\n");
 						build_chap_response(b, 2, n, &chapresponse);
 					}
 					break;
+				case 13:    // Response
+					// Why did they send a response? We never challenge.
+					LOG(2, s, t, "   received unexpected challenge response\n");
+					break;
+
 				case 14:    // assigned session
 					asession = session[s].far = ntohs(*(u16 *) (b));
-					log(4, ntohl(addr->sin_addr.s_addr), s, t, "   assigned session = %d\n", asession);
+					LOG(4, s, t, "   assigned session = %d\n", asession);
 					break;
 				case 15:    // call serial number
-					log(4, ntohl(addr->sin_addr.s_addr), s, t, "   call serial number = %d\n", ntohl(*(u32 *)b));
+					LOG(4, s, t, "   call serial number = %d\n", ntohl(*(u32 *)b));
 					break;
 				case 18:    // bearer type
-					log(4, ntohl(addr->sin_addr.s_addr), s, t, "   bearer type = %d\n", ntohl(*(u32 *)b));
+					LOG(4, s, t, "   bearer type = %d\n", ntohl(*(u32 *)b));
 					// TBA - for RADIUS
 					break;
 				case 19:    // framing type
-					log(4, ntohl(addr->sin_addr.s_addr), s, t, "   framing type = %d\n", ntohl(*(u32 *)b));
+					LOG(4, s, t, "   framing type = %d\n", ntohl(*(u32 *)b));
 					// TBA
 					break;
 				case 21:    // called number
 					memset(called, 0, MAXTEL);
 					memcpy(called, b, (n >= MAXTEL) ? (MAXTEL-1) : n);
-					log(4, ntohl(addr->sin_addr.s_addr), s, t, "   Called <%s>\n", called);
+					LOG(4, s, t, "   Called <%s>\n", called);
 					break;
 				case 22:    // calling number
 					memset(calling, 0, MAXTEL);
 					memcpy(calling, b, (n >= MAXTEL) ? (MAXTEL-1) : n);
-					log(4, ntohl(addr->sin_addr.s_addr), s, t, "   Calling <%s>\n", calling);
+					LOG(4, s, t, "   Calling <%s>\n", calling);
+					break;
+				case 23:    // subtype
 					break;
 				case 24:    // tx connect speed
 					if (n == 4)
@@ -1294,8 +1649,7 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 						memcpy(tmp, b, (n >= 30) ? 30 : n);
 						session[s].tx_connect_speed = atol(tmp);
 					}
-					log(4, ntohl(addr->sin_addr.s_addr), s, t, "   TX connect speed <%d>\n",
-							session[s].tx_connect_speed);
+					LOG(4, s, t, "   TX connect speed <%u>\n", session[s].tx_connect_speed);
 					break;
 				case 38:    // rx connect speed
 					if (n == 4)
@@ -1309,20 +1663,18 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 						memcpy(tmp, b, (n >= 30) ? 30 : n);
 						session[s].rx_connect_speed = atol(tmp);
 					}
-					log(4, ntohl(addr->sin_addr.s_addr), s, t, "   RX connect speed <%d>\n",
-							session[s].rx_connect_speed);
+					LOG(4, s, t, "   RX connect speed <%u>\n", session[s].rx_connect_speed);
 					break;
 				case 25:    // Physical Channel ID
 					{
 						u32 tmp = ntohl(*(u32 *)b);
-						log(4, ntohl(addr->sin_addr.s_addr), s, t, "   Physical Channel ID <%X>\n", tmp);
+						LOG(4, s, t, "   Physical Channel ID <%X>\n", tmp);
 						break;
 					}
 				case 29:    // Proxy Authentication Type
 					{
 						u16 authtype = ntohs(*(u16 *)b);
-						log(4, ntohl(addr->sin_addr.s_addr), s, t, "   Proxy Auth Type %d (%s)\n",
-							authtype, authtypes[authtype]);
+						LOG(4, s, t, "   Proxy Auth Type %d (%s)\n", authtype, authtypes[authtype]);
 						requestchap = (authtype == 2);
 						break;
 					}
@@ -1330,21 +1682,20 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 					{
 						char authname[64] = {0};
 						memcpy(authname, b, (n > 63) ? 63 : n);
-						log(4, ntohl(addr->sin_addr.s_addr), s, t, "   Proxy Auth Name (%s)\n",
+						LOG(4, s, t, "   Proxy Auth Name (%s)\n",
 							authname);
 						break;
 					}
 				case 31:    // Proxy Authentication Challenge
 					{
 						memcpy(radius[session[s].radius].auth, b, 16);
-						log(4, ntohl(addr->sin_addr.s_addr), s, t, "   Proxy Auth Challenge (%X)\n", radius[session[s].radius].auth);
+						LOG(4, s, t, "   Proxy Auth Challenge\n");
 						break;
 					}
 				case 32:    // Proxy Authentication ID
 					{
 						u16 authid = ntohs(*(u16 *)(b));
-						log(4, ntohl(addr->sin_addr.s_addr), s, t, "   Proxy Auth ID (%d)\n",
-							authid);
+						LOG(4, s, t, "   Proxy Auth ID (%d)\n", authid);
 						if (session[s].radius)
 							radius[session[s].radius].id = authid;
 						break;
@@ -1353,56 +1704,40 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 					{
 						char authresp[64] = {0};
 						memcpy(authresp, b, (n > 63) ? 63 : n);
-						log(4, ntohl(addr->sin_addr.s_addr), s, t, "   Proxy Auth Response\n");
+						LOG(4, s, t, "   Proxy Auth Response\n");
 						break;
 					}
 				case 27:    // last send lcp
 					{        // find magic number
 						u8 *p = b, *e = p + n;
-						while (p < e && p[1])
+						while (p + 1 < e && p[1] && p + p[1] <= e)
 						{
-							if (*p == 5 && p[1] == 6)
+							if (*p == 5 && p[1] == 6) // Magic-Number
 								amagic = ntohl(*(u32 *) (p + 2));
-							else if (*p == 3 && p[1] == 5 && *(u16 *) (p + 2) == htons(PPPCHAP) && p[4] == 5)
+							else if (*p == 3 && p[1] == 5 && *(u16 *) (p + 2) == htons(PPPCHAP) && p[4] == 5) // Authentication-Protocol
 								chap = 1;
-							else if (*p == 7)
+							else if (*p == 7) // Protocol-Field-Compression
 								aflags |= SESSIONPFC;
-							else if (*p == 8)
+							else if (*p == 8) // Address-and-Control-Field-Compression
 								aflags |= SESSIONACFC;
 							p += p[1];
 						}
-
-						{
-							char tmp[500] = {0};
-							tmp[0] = ConfigReq;
-							memcpy((tmp + 1), b, n);
-						}
 					}
 					break;
 				case 28:    // last recv lcp confreq
-					{
-						char tmp[500] = {0};
-						tmp[0] = ConfigReq;
-						memcpy((tmp + 1), b, n);
-						break;
-					}
+					break;
 				case 26:    // Initial Received LCP CONFREQ
-					{
-						char tmp[500] = {0};
-						tmp[0] = ConfigReq;
-						memcpy((tmp + 1), b, n);
-					}
 					break;
 				case 39:    // seq required - we control it as an LNS anyway...
 					break;
 				case 36:    // Random Vector
-					log(4, ntohl(addr->sin_addr.s_addr), s, t, "   Random Vector received. Enabled AVP Hiding.\n");
+					LOG(4, s, t, "   Random Vector received. Enabled AVP Hiding.\n");
 					memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
 					memcpy(session[s].random_vector, b, n);
 					session[s].random_vector_length = n;
 					break;
 				default:
-					log(2, ntohl(addr->sin_addr.s_addr), s, t, "   Unknown AVP type %d\n", mtype);
+					LOG(2, s, t, "   Unknown AVP type %d\n", mtype);
 					fatal = flags;
 					continue; // next
 				}
@@ -1457,17 +1792,20 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 					}
 					else
 					{
-						u8 r;
+						u16 r;
 						controlt *c;
 
 						s = sessionfree;
 						sessionfree = session[s].next;
 						memset(&session[s], 0, sizeof(session[s]));
 
+						if (s > config->cluster_highest_sessionid)
+							config->cluster_highest_sessionid = s;
+
 						// make a RADIUS session
 						if (!(r = radiusnew(s)))
 						{
-							log(1, ntohl(addr->sin_addr.s_addr), s, t, "No free RADIUS sessions for ICRQ\n");
+							LOG(1, s, t, "No free RADIUS sessions for ICRQ\n");
 							sessionkill(s, "no free RADIUS sesions");
 							return;
 						}
@@ -1478,7 +1816,7 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 						session[s].tunnel = t;
 						session[s].far = asession;
 						session[s].last_packet = time_now;
-						log(3, ntohl(addr->sin_addr.s_addr), s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
+						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
 						{
@@ -1497,9 +1835,10 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 					// TBA
 					break;
 				case 12:      // ICCN
+					if (amagic == 0) amagic = time_now;
 					session[s].magic = amagic; // set magic number
-					session[s].flags = aflags; // set flags received
-					log(3, ntohl(addr->sin_addr.s_addr), s, t, "Magic %X Flags %X\n", amagic, aflags);
+					session[s].l2tp_flags = aflags; // set flags received
+					LOG(3, s, t, "Magic %X Flags %X\n", amagic, aflags);
 					controlnull(t); // ack
 					// In CHAP state, request PAP instead
 					if (requestchap)
@@ -1510,14 +1849,14 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 					sessionshutdown(s, "Closed (Received CDN)");
 					break;
 				case 0xFFFF:
-					log(1, ntohl(addr->sin_addr.s_addr), s, t, "Missing message type\n");
+					LOG(1, s, t, "Missing message type\n");
 					break;
 				default:
 					STAT(tunnel_rx_errors);
 					if (mandatorymessage & 0x80)
 						tunnelshutdown(t, "Unknown message");
 					else
-						log(1, ntohl(addr->sin_addr.s_addr), s, t, "Unknown message type %d\n", message);
+						LOG(1, s, t, "Unknown message type %d\n", message);
 					break;
 				}
 			if (chapresponse) free(chapresponse);
@@ -1525,19 +1864,14 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 		}
 		else
 		{
-			log(4, 0, s, t, "   Got a ZLB ack\n");
+			LOG(4, s, t, "   Got a ZLB ack\n");
 		}
 	}
 	else
 	{                          // data
 		u16 prot;
 
-		log_hex(5, "Receive Tunnel Data", p, l);
-		if (session[s].die)
-		{
-			log(3, ntohl(addr->sin_addr.s_addr), s, t, "Session %d is closing. Don't process PPP packets\n", s);
-			return;              // closing session, PPP not processed
-		}
+		LOG_HEX(5, "Receive Tunnel Data", p, l);
 		if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
 		{                     // HDLC address header, discard
 			p += 2;
@@ -1545,7 +1879,7 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 		}
 		if (l < 2)
 		{
-			log(1, ntohl(addr->sin_addr.s_addr), s, t, "Short ppp length %d\n", l);
+			LOG(1, s, t, "Short ppp length %d\n", l);
 			STAT(tunnel_rx_errors);
 			return;
 		}
@@ -1560,412 +1894,773 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 			p += 2;
 			l -= 2;
 		}
+
+		if (s && !session[s].tunnel)	// Is something wrong??
+		{
+			if (!config->cluster_iam_master)
+			{
+				// Pass it off to the master to deal with..
+				master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
+				return;
+			}
+
+
+			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);
+
+			STAT(tunnel_rx_errors);
+			return;
+		}
+
+		if (session[s].die)
+		{
+			LOG(3, s, t, "Session %d is closing. Don't process PPP packets\n", s);
+// I'm pretty sure this isn't right -- mo.
+//			return;              // closing session, PPP not processed
+		}
 		if (prot == PPPPAP)
 		{
 			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; }
 			processpap(t, s, p, l);
 		}
 		else if (prot == PPPCHAP)
 		{
 			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; }
 			processchap(t, s, p, l);
 		}
 		else if (prot == PPPLCP)
 		{
 			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; }
 			processlcp(t, s, p, l);
 		}
 		else if (prot == PPPIPCP)
 		{
 			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; }
 			processipcp(t, s, p, l);
 		}
 		else if (prot == PPPCCP)
 		{
 			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; }
 			processccp(t, s, p, l);
 		}
 		else if (prot == PPPIP)
 		{
 			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;
+			}
 			processipin(t, s, p, l);
 		}
 		else
 		{
 			STAT(tunnel_rx_errors);
-			log(1, ntohl(addr->sin_addr.s_addr), s, t, "Unknown PPP protocol %04X\n", prot);
+			LOG(1, s, t, "Unknown PPP protocol %04X\n", prot);
 		}
 	}
 }
 
-// read and process packet on tap
-void processtap(u8 * buf, int len)
+// read and process packet on tun
+static void processtun(u8 * buf, int len)
 {
-	log_hex(5, "Receive TAP Data", buf, len);
-	STAT(tap_rx_packets);
-	INC_STAT(tap_rx_bytes, len);
-#ifdef STAT_CALLS
-	STAT(call_processtap);
-#endif
+	LOG_HEX(5, "Receive TUN Data", buf, len);
+	STAT(tun_rx_packets);
+	INC_STAT(tun_rx_bytes, len);
+
+	CSTAT(call_processtun);
+
 	eth_rx_pkt++;
 	eth_rx += len;
 	if (len < 22)
 	{
-		log(1, 0, 0, 0, "Short tap packet %d bytes\n", len);
-		STAT(tap_rx_errors);
+		LOG(1, 0, 0, "Short tun packet %d bytes\n", len);
+		STAT(tun_rx_errors);
 		return;
 	}
-	if (*(u16 *) (buf + 2) == htons(PKTARP)) // ARP
-		processarp(buf, len);
-	else if (*(u16 *) (buf + 2) == htons(PKTIP)) // ARP
+
+	if (*(u16 *) (buf + 2) == htons(PKTIP)) // IP
 		processipout(buf, len);
-	else
-	{
-		log(1, 0, 0, 0, "Unexpected tap packet %04X, %d bytes\n", ntohs(*(u16 *) (buf + 2)), len);
-	}
+	// Else discard.
 }
 
-// main loop - gets packets on tap or udp and processes them
-void mainloop(void)
+//
+// Maximum number of actions to complete.
+// This is to avoid sending out too many packets
+// at once.
+#define MAX_ACTIONS 500
+
+static int regular_cleanups(void)
 {
-	fd_set cr;
-	int cn;
-	u8 buf[65536];
-	struct timeval to;
-	clockt slow = now();       // occasional functions like session/tunnel expiry, tunnel hello, etc
-	clockt next_acct = slow + ACCT_TIME;
-	clockt next_cluster_ping = slow + 50;
-	to.tv_sec = 1;
-	to.tv_usec = 0;
-	log(4, 0, 0, 0, "Beginning of main loop. udpfd=%d, tapfd=%d, radfd=%d, cluster_sockfd=%d, controlfd=%d\n",
-			udpfd, tapfd, radfd, cluster_sockfd, controlfd);
-
-	FD_ZERO(&cr);
-	FD_SET(udpfd, &cr);
-	FD_SET(tapfd, &cr);
-	FD_SET(radfd, &cr);
-	FD_SET(controlfd, &cr);
-	FD_SET(clifd, &cr);
-	if (cluster_sockfd) FD_SET(cluster_sockfd, &cr);
-	cn = udpfd;
-	if (cn < radfd) cn = radfd;
-	if (cn < tapfd) cn = tapfd;
-	if (cn < controlfd) cn = controlfd;
-	if (cn < clifd) cn = clifd;
-	if (cn < cluster_sockfd) cn = cluster_sockfd;
-
-	while (!main_quit)
-	{
-		fd_set r;
-		int n = cn;
+	static sessionidt s = 0;	// Next session to check for actions on.
+	tunnelidt t;
+	int count=0,i;
+	u16 r;
+	static clockt next_acct = 0;
+	int a;
 
-		if (config->reload_config)
+	LOG(3, 0, 0, "Begin regular cleanup\n");
+
+	for (r = 1; r < MAXRADIUS; r++)
+	{
+		if (!radius[r].state)
+			continue;
+		if (radius[r].retry)
 		{
-			// Update the config state based on config settings
-			update_config();
+			if (radius[r].retry <= TIME)
+				radiusretry(r);
+		} else
+			radius[r].retry = backoff(radius[r].try+1);	// Is this really needed? --mo
+	}
+	for (t = 1; t <= config->cluster_highest_tunnelid; t++)
+	{
+		// check for expired tunnels
+		if (tunnel[t].die && tunnel[t].die <= TIME)
+		{
+			STAT(tunnel_timeout);
+			tunnelkill(t, "Expired");
+			continue;
 		}
-
-		memcpy(&r, &cr, sizeof(fd_set));
-		n = select(n + 1, &r, 0, 0, &to);
-		if (n < 0)
+		// check for message resend
+		if (tunnel[t].retry && tunnel[t].controlc)
 		{
-			if (errno != EINTR)
+			// resend pending messages as timeout on reply
+			if (tunnel[t].retry <= TIME)
 			{
-				perror("select");
-				exit( -1);
+				controlt *c = tunnel[t].controls;
+				u8 w = tunnel[t].window;
+				tunnel[t].try++; // another try
+				if (tunnel[t].try > 5)
+					tunnelkill(t, "Timeout on control message"); // game over
+				else
+					while (c && w--)
+					{
+						tunnelsend(c->buf, c->length, t);
+						c = c->next;
+					}
 			}
 		}
-		else if (n)
+		// Send hello
+		if (tunnel[t].state == TUNNELOPEN && tunnel[t].lastrec < TIME + 600)
 		{
-			struct sockaddr_in addr;
-			int alen = sizeof(addr);
-			if (FD_ISSET(udpfd, &r))
-				processudp(buf, recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen), &addr);
-			else if (FD_ISSET(tapfd, &r))
-				processtap(buf, read(tapfd, buf, sizeof(buf)));
-			else if (FD_ISSET(radfd, &r))
-				processrad(buf, recv(radfd, buf, sizeof(buf), 0));
-			else if (FD_ISSET(cluster_sockfd, &r))
-				processcluster(buf, recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen));
-			else if (FD_ISSET(controlfd, &r))
-				processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr);
-			else if (FD_ISSET(clifd, &r))
-			{
-				struct sockaddr_in addr;
-				int sockfd;
-				int len = sizeof(addr);
+			controlt *c = controlnew(6); // sending HELLO
+			controladd(c, t, 0); // send the message
+			LOG(3, 0, t, "Sending HELLO message\n");
+		}
 
-				if ((sockfd = accept(clifd, (struct sockaddr *)&addr, &len)) <= 0)
-				{
-					log(0, 0, 0, 0, "accept error: %s\n", strerror(errno));
-					continue;
-				}
-				else
-				{
-					cli_do(sockfd);
-					close(sockfd);
-				}
-			}
-			else
+		// Check for tunnel changes requested from the CLI
+		if ((a = cli_tunnel_actions[t].action))
+		{
+			cli_tunnel_actions[t].action = 0;
+			if (a & CLI_TUN_KILL)
 			{
-				log(1, 0, 0, 0, "Main select() loop returned %d, but no fds have data waiting\n", n);
-				continue;
+				LOG(2, 0, t, "Dropping tunnel by CLI\n");
+				tunnelshutdown(t, "Requested by administrator");
 			}
 		}
-		else if (n == 0) {                       // handle timeouts
-			clockt when = now();
-			clockt best = when + 100; // default timeout
-			sessionidt s;
-			tunnelidt t;
-			u8 r;
 
-			for (r = 1; r < MAXRADIUS; r++)
-				if (radius[r].state && radius[r].retry)
-				{
-					if (radius[r].retry <= when)
-						radiusretry(r);
-					if (radius[r].retry && radius[r].retry < best)
-						best = radius[r].retry;
-				}
-			for (t = 1; t < MAXTUNNEL; t++)
+	}
+
+	count = 0;
+	for (i = 1; i <= config->cluster_highest_sessionid; i++)
+	{
+		s++;
+		if (s > config->cluster_highest_sessionid)
+			s = 1;
+
+		if (!session[s].tunnel)	// Session isn't in use
+			continue;
+
+		if (!session[s].die && session[s].ip && !(session[s].flags & SF_IPCP_ACKED))
+		{
+			// IPCP has not completed yet. Resend
+			LOG(3, s, session[s].tunnel, "No ACK for initial IPCP ConfigReq... resending\n");
+			sendipcp(session[s].tunnel, s);
+		}
+
+		// check for expired sessions
+		if (session[s].die && session[s].die <= TIME)
+		{
+			sessionkill(s, "Expired");
+			if (++count >= MAX_ACTIONS) break;
+			continue;
+		}
+
+		// Drop sessions who have not responded within IDLE_TIMEOUT seconds
+		if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
+		{
+			sessionkill(s, "No response to LCP ECHO requests");
+			STAT(session_timeout);
+			if (++count >= MAX_ACTIONS) break;
+			continue;
+		}
+
+		// No data in IDLE_TIMEOUT seconds, send LCP ECHO
+		if (session[s].user[0] && (time_now - session[s].last_packet >= ECHO_TIMEOUT))
+		{
+			u8 b[MAXCONTROL] = {0};
+
+			u8 *q = makeppp(b, sizeof(b), 0, 0, session[s].tunnel, s, PPPLCP);
+			if (!q) continue;
+
+			*q = EchoReq;
+			*(u8 *)(q + 1) = (time_now % 255); // ID
+			*(u16 *)(q + 2) = htons(8); // Length
+			*(u32 *)(q + 4) = 0; // Magic Number (not supported)
+
+			LOG(4, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
+					(int)(time_now - session[s].last_packet));
+			tunnelsend(b, 24, session[s].tunnel); // send it
+			if (++count >= MAX_ACTIONS) break;
+		}
+
+		// Check for actions requested from the CLI
+		if ((a = cli_session_actions[s].action))
+		{
+			int send = 0;
+
+			cli_session_actions[s].action = 0;
+			if (a & CLI_SESS_KILL)
 			{
-				// check for expired tunnels
-				if (tunnel[t].die && tunnel[t].die <= when)
-				{
-					STAT(tunnel_timeout);
-					tunnelkill(t, "Expired");
-					continue;
-				}
-				// check for message resend
-				if (tunnel[t].retry && tunnel[t].controlc)
-				{
-					// resend pending messages as timeout on reply
-					if (tunnel[t].retry <= when)
-					{
-						controlt *c = tunnel[t].controls;
-						u8 w = tunnel[t].window;
-						tunnel[t].try++; // another try
-						if (tunnel[t].try > 5)
-							tunnelkill(t, "Timeout on control message"); // game over
-						else
-							while (c && w--)
-							{
-								tunnelsend(c->buf, c->length, t);
-								c = c->next;
-							}
-					}
-					if (tunnel[t].retry && tunnel[t].retry < best)
-						best = tunnel[t].retry;
-				}
-				// Send hello
-				if (tunnel[t].state == TUNNELOPEN && tunnel[t].lastrec < when + 600)
-				{
-					controlt *c = controlnew(6); // sending HELLO
-					controladd(c, t, 0); // send the message
-					log(3, tunnel[t].ip, 0, t, "Sending HELLO message\n");
-				}
+				LOG(2, s, session[s].tunnel, "Dropping session by CLI\n");
+				sessionshutdown(s, "Requested by administrator");
+				a = 0; // dead, no need to check for other actions
 			}
 
-			// Check for sessions that have been killed from the CLI
-			if (cli_session_kill[0])
+			if (a & CLI_SESS_NOSNOOP)
 			{
-				int i;
-				for (i = 1; i < MAXSESSION && cli_session_kill[i]; i++)
-				{
-					log(2, 0, cli_session_kill[i], 0, "Dropping session by CLI\n");
-					sessionshutdown(cli_session_kill[i], "Requested by administrator");
-					cli_session_kill[i] = 0;
-				}
+				LOG(2, s, session[s].tunnel, "Unsnooping session by CLI\n");
+				session[s].snoop_ip = 0;
+				session[s].snoop_port = 0;
+				send++;
 			}
-			// Check for tunnels that have been killed from the CLI
-			if (cli_tunnel_kill[0])
+			else if (a & CLI_SESS_SNOOP)
 			{
-				int i;
-				for (i = 1; i < MAXTUNNEL && cli_tunnel_kill[i]; i++)
-				{
-					log(2, 0, cli_tunnel_kill[i], 0, "Dropping tunnel by CLI\n");
-					tunnelshutdown(cli_tunnel_kill[i], "Requested by administrator");
-					cli_tunnel_kill[i] = 0;
-				}
+				LOG(2, s, session[s].tunnel, "Snooping session by CLI (to %s:%d)\n",
+				    fmtaddr(cli_session_actions[s].snoop_ip, 0),
+				    cli_session_actions[s].snoop_port);
+
+				session[s].snoop_ip = cli_session_actions[s].snoop_ip;
+				session[s].snoop_port = cli_session_actions[s].snoop_port;
+				send++;
 			}
 
-			for (s = 1; s < MAXSESSION; s++)
+			if (a & CLI_SESS_NOTHROTTLE)
 			{
-				// check for expired sessions
-				if (session[s].die && session[s].die <= when)
-				{
-					sessionkill(s, "Expired");
-					continue;
-				}
-
-				// Drop sessions who have not responded within IDLE_TIMEOUT seconds
-				if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
-				{
-					sessionkill(s, "No response to LCP ECHO requests");
-					STAT(session_timeout);
-					continue;
-				}
-
-				// No data in IDLE_TIMEOUT seconds, send LCP ECHO
-				if (session[s].user[0] && (time_now - session[s].last_packet >= ECHO_TIMEOUT))
-				{
-					u8 b[MAXCONTROL] = {0};
-					u8 *q = makeppp(b, 0, 0, session[s].tunnel, s, PPPLCP);
-
-					*q = EchoReq;
-					*(u8 *)(q + 1) = (time_now % 255); // ID
-					*(u16 *)(q + 2) = htons(8); // Length
-					*(u32 *)(q + 4) = 0; // Magic Number (not supported)
-
-					log(4, session[s].ip, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
-							time_now - session[s].last_packet);
-					tunnelsend(b, 24, session[s].tunnel); // send it
-					continue;
-				}
+				LOG(2, s, session[s].tunnel, "Un-throttling session by CLI\n");
+				throttle_session(s, 0, 0);
+				send++;
 			}
-			if (config->accounting_dir && next_acct <= when)
+			else if (a & CLI_SESS_THROTTLE)
 			{
-				// Dump accounting data
-				next_acct = when + ACCT_TIME;
-				dump_acct_info();
+				LOG(2, s, session[s].tunnel, "Throttling session by CLI (to %dkb/s up and %dkb/s down)\n",
+				    cli_session_actions[s].throttle_in,
+				    cli_session_actions[s].throttle_out);
+
+				throttle_session(s, cli_session_actions[s].throttle_in, cli_session_actions[s].throttle_out);
+				send++;
 			}
 
-			if (cluster_sockfd && next_cluster_ping <= when)
+			if (a & CLI_SESS_NOFILTER)
+			{
+				LOG(2, s, session[s].tunnel, "Un-filtering session by CLI\n");
+				filter_session(s, 0, 0);
+				send++;
+			}
+			else if (a & CLI_SESS_FILTER)
 			{
-				// Dump accounting data
-				next_cluster_ping = when + 50;
-				cluster_send_message(config->cluster_address, config->bind_address, C_PING, hostname, strlen(hostname));
+				LOG(2, s, session[s].tunnel, "Filtering session by CLI (in=%d, out=%d)\n",
+				    cli_session_actions[s].filter_in,
+				    cli_session_actions[s].filter_out);
+
+				filter_session(s, cli_session_actions[s].filter_in, cli_session_actions[s].filter_out);
+				send++;
 			}
 
-			if (best <= when)
-				best = when + 1;  // should not really happen
-			to.tv_sec = (best - when) / 10;
-			to.tv_usec = 100000 * ((best - when) % 10);
-			log(5, 0, 0, 0, "Next time check in %d.%d seconds\n", (best - when) / 10, ((best - when) % 10));
+			if (send)
+				cluster_send_session(s);
+
+			if (++count >= MAX_ACTIONS) break;
 		}
 	}
+
+	if (*config->accounting_dir && next_acct <= TIME)
+	{
+		// Dump accounting data
+		next_acct = TIME + ACCT_TIME;
+		dump_acct_info();
+	}
+
+	if (count >= MAX_ACTIONS)
+		return 1;	// Didn't finish!
+
+	LOG(3, 0, 0, "End regular cleanup (%d actions), next in %d seconds\n", count, config->cleanup_interval);
+	return 0;
 }
 
-// Init data structures
-void initdata(void)
+
+//
+// Are we in the middle of a tunnel update, or radius
+// requests??
+//
+static int still_busy(void)
 {
 	int i;
+	static clockt last_talked = 0;
+	static clockt start_busy_wait = 0;
+	if (start_busy_wait == 0)
+		start_busy_wait = TIME;
 
-	_statistics = mmap(NULL, sizeof(struct Tstats), PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
-	if (_statistics == MAP_FAILED)
-	{
-		log(0, 0, 0, 0, "Error doing mmap for _statistics: %s\n", strerror(errno));
-		exit(1);
-	}
-	config = mmap(NULL, sizeof(struct configt), PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
-	if (config == MAP_FAILED)
-	{
-		log(0, 0, 0, 0, "Error doing mmap for configuration: %s\n", strerror(errno));
-		exit(1);
-	}
-	memset(config, 0, sizeof(struct configt));
-	time(&config->start_time);
-	strncpy(config->config_file, CONFIGFILE, sizeof(config->config_file) - 1);
-	tunnel = mmap(NULL, sizeof(tunnelt) * MAXTUNNEL, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
-	if (tunnel == MAP_FAILED)
-	{
-		log(0, 0, 0, 0, "Error doing mmap for tunnels: %s\n", strerror(errno));
-		exit(1);
-	}
-	session = mmap(NULL, sizeof(sessiont) * MAXSESSION, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
-	if (session == MAP_FAILED)
-	{
-		log(0, 0, 0, 0, "Error doing mmap for sessions: %s\n", strerror(errno));
-		exit(1);
-	}
-	radius = mmap(NULL, sizeof(radiust) * MAXRADIUS, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
-	if (radius == MAP_FAILED)
-	{
-		log(0, 0, 0, 0, "Error doing mmap for radius: %s\n", strerror(errno));
-		exit(1);
-	}
-	ip_address_pool = mmap(NULL, sizeof(ippoolt) * MAXIPPOOL, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
-	if (ip_address_pool == MAP_FAILED)
-	{
-		log(0, 0, 0, 0, "Error doing mmap for radius: %s\n", strerror(errno));
-		exit(1);
-	}
-#ifdef RINGBUFFER
-	ringbuffer = mmap(NULL, sizeof(struct Tringbuffer), PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
-	if (ringbuffer == MAP_FAILED)
+	for (i = config->cluster_highest_tunnelid ; i > 0 ; --i)
 	{
-		log(0, 0, 0, 0, "Error doing mmap for radius: %s\n", strerror(errno));
-		exit(1);
-	}
-	memset(ringbuffer, 0, sizeof(struct Tringbuffer));
-#endif
+		if (!tunnel[i].controlc)
+			continue;
 
-	cli_session_kill = mmap(NULL, sizeof(sessionidt) * MAXSESSION, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
-	if (cli_session_kill == MAP_FAILED)
-	{
-		log(0, 0, 0, 0, "Error doing mmap for cli session kill: %s\n", strerror(errno));
-		exit(1);
+		if (last_talked != TIME)
+		{
+			LOG(2, 0, 0, "Tunnel %d still has un-acked control messages.\n", i);
+			last_talked = TIME;
+		}
+		return 1;
 	}
-	memset(cli_session_kill, 0, sizeof(sessionidt) * MAXSESSION);
-	cli_tunnel_kill = mmap(NULL, sizeof(tunnelidt) * MAXSESSION, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
-	if (cli_tunnel_kill == MAP_FAILED)
+
+	// We stop waiting for radius after BUSY_WAIT_TIME 1/10th seconds
+	if (abs(TIME - start_busy_wait) > BUSY_WAIT_TIME)
 	{
-		log(0, 0, 0, 0, "Error doing mmap for cli tunnel kill: %s\n", strerror(errno));
-		exit(1);
+		LOG(1, 0, 0, "Giving up waiting for RADIUS to be empty. Shutting down anyway.\n");
+		return 0;
 	}
-	memset(cli_tunnel_kill, 0, sizeof(tunnelidt) * MAXSESSION);
 
-	filter_buckets = mmap(NULL, sizeof(tbft) * MAXSESSION, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
-	if (filter_buckets == MAP_FAILED)
+	for (i = 1; i < MAXRADIUS; i++)
 	{
-		log(0, 0, 0, 0, "Error doing mmap for filter buckets: %s\n", strerror(errno));
-		exit(1);
-	}
-	memset(filter_buckets, 0, sizeof(tbft) * MAXSESSION);
+		if (radius[i].state == RADIUSNULL)
+			continue;
+	        if (radius[i].state == RADIUSWAIT)
+			continue;
 
-	memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
+		if (last_talked != TIME)
+		{
+			LOG(2, 0, 0, "Radius session %d is still busy (sid %d)\n", i, radius[i].session);
+			last_talked = TIME;
+		}
+		return 1;
+	}
+
+	return 0;
+}
+
+static fd_set readset;
+static int readset_n = 0;
+
+// main loop - gets packets on tun or udp and processes them
+static void mainloop(void)
+{
+	int i;
+	u8 buf[65536];
+	struct timeval to;
+	clockt next_cluster_ping = 0;	// send initial ping immediately
+	time_t next_clean = time_now + config->cleanup_interval;
+
+	LOG(4, 0, 0, "Beginning of main loop. udpfd=%d, tunfd=%d, cluster_sockfd=%d, controlfd=%d\n",
+		udpfd, tunfd, cluster_sockfd, controlfd);
+
+	FD_ZERO(&readset);
+	FD_SET(udpfd, &readset);
+	FD_SET(tunfd, &readset);
+	FD_SET(controlfd, &readset);
+	FD_SET(clifd, &readset);
+	if (cluster_sockfd) FD_SET(cluster_sockfd, &readset);
+	readset_n = udpfd;
+	if (tunfd > readset_n)          readset_n = tunfd;
+	if (controlfd > readset_n)      readset_n = controlfd;
+	if (clifd > readset_n)          readset_n = clifd;
+	if (cluster_sockfd > readset_n) readset_n = cluster_sockfd;
+
+	while (!main_quit || still_busy())
+	{
+		fd_set r;
+		int n = readset_n;
+#ifdef BGP
+		fd_set w;
+		int bgp_set[BGP_NUM_PEERS];
+#endif /* BGP */
+
+		if (config->reload_config)
+		{
+			// Update the config state based on config settings
+			update_config();
+		}
+
+		memcpy(&r, &readset, sizeof(fd_set));
+		to.tv_sec = 0;
+		to.tv_usec = 100000; // 1/10th of a second.
+
+#ifdef BGP
+		FD_ZERO(&w);
+		for (i = 0; i < BGP_NUM_PEERS; i++)
+		{
+			bgp_set[i] = bgp_select_state(&bgp_peers[i]);
+			if (bgp_set[i] & 1)
+			{
+				FD_SET(bgp_peers[i].sock, &r);
+				if (bgp_peers[i].sock > n)
+					n = bgp_peers[i].sock;
+			}
+
+			if (bgp_set[i] & 2)
+			{
+				FD_SET(bgp_peers[i].sock, &w);
+				if (bgp_peers[i].sock > n)
+					n = bgp_peers[i].sock;
+			}
+		}
+
+		n = select(n + 1, &r, &w, 0, &to);
+#else /* BGP */
+		n = select(n + 1, &r, 0, 0, &to);
+#endif /* BGP */
+
+		TIME = now();
+		if (n < 0)
+		{
+			if (errno == EINTR ||
+			    errno == ECHILD) // EINTR was clobbered by sigchild_handler()
+				continue;
+
+			LOG(0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
+			main_quit++;
+			break;
+		}
+		else if (n)
+		{
+			struct sockaddr_in addr;
+			int alen = sizeof(addr);
+			if (FD_ISSET(udpfd, &r))
+			{
+				int c, n;
+				for (c = 0; c < config->multi_read_count; c++)
+				{
+					if ((n = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
+						processudp(buf, n, &addr);
+					else
+						break;
+				}
+			}
+			if (FD_ISSET(tunfd, &r))
+			{
+				int c, n;
+				for (c = 0; c < config->multi_read_count; c++)
+				{
+					if ((n = read(tunfd, buf, sizeof(buf))) > 0)
+						processtun(buf, n);
+					else
+						break;
+				}
+			}
+
+			if (config->cluster_iam_master)
+				for (i = 0; i < config->num_radfds; i++)
+					if (FD_ISSET(radfds[i], &r))
+						processrad(buf, recv(radfds[i], buf, sizeof(buf), 0), i);
+
+			if (FD_ISSET(cluster_sockfd, &r))
+			{
+				int size;
+				size = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen);
+				processcluster(buf, size, addr.sin_addr.s_addr);
+			}
+
+			if (FD_ISSET(controlfd, &r))
+				processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
+
+			if (FD_ISSET(clifd, &r))
+			{
+				struct sockaddr_in addr;
+				int sockfd;
+				int len = sizeof(addr);
+
+				if ((sockfd = accept(clifd, (struct sockaddr *)&addr, &len)) <= 0)
+				{
+					LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
+					continue;
+				}
+				else
+				{
+					cli_do(sockfd);
+					close(sockfd);
+				}
+			}
+		}
+
+			// Runs on every machine (master and slaves).
+		if (cluster_sockfd && next_cluster_ping <= TIME)
+		{
+			// Check to see which of the cluster is still alive..
+
+			cluster_send_ping(basetime);	// Only does anything if we're a slave
+			cluster_check_master();		// ditto.
+
+			cluster_heartbeat();		// Only does anything if we're a master.
+			cluster_check_slaves();		// ditto.
+
+			master_update_counts();		// If we're a slave, send our byte counters to our master.
+
+			if (config->cluster_iam_master && !config->cluster_iam_uptodate)
+				next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
+			else
+				next_cluster_ping = TIME + config->cluster_hb_interval;
+		}
+
+			// Run token bucket filtering queue..
+			// Only run it every 1/10th of a second.
+			// Runs on all machines both master and slave.
+		{
+			static clockt last_run = 0;
+			if (last_run != TIME)
+			{
+				last_run = TIME;
+				tbf_run_timer();
+			}
+		}
+
+		/* Handle timeouts. Make sure that this gets run anyway, even if there was
+		 * something to read, else under load this will never actually run....
+		 *
+		 */
+		if (config->cluster_iam_master && next_clean <= time_now)
+		{
+			if (regular_cleanups())
+			{
+				// Did it finish?
+				next_clean = time_now + 1 ;	// Didn't finish. Check quickly.
+			}
+			else
+			{
+				next_clean = time_now + config->cleanup_interval; // Did. Move to next interval.
+			}
+		}
+
+#ifdef BGP
+		for (i = 0; i < BGP_NUM_PEERS; i++)
+		{
+			bgp_process(&bgp_peers[i],
+				bgp_set[i] ? FD_ISSET(bgp_peers[i].sock, &r) : 0,
+				bgp_set[i] ? FD_ISSET(bgp_peers[i].sock, &w) : 0);
+		}
+#endif /* BGP */
+	}
+
+		// Are we the master and shutting down??
+	if (config->cluster_iam_master)
+		cluster_heartbeat(); // Flush any queued changes..
+
+		// Ok. Notify everyone we're shutting down. If we're
+		// the master, this will force an election.
+	cluster_send_ping(0);
+
+	//
+	// Important!!! We MUST not process any packets past this point!
+}
+
+static void stripdomain(char *host)
+{
+	char *p;
+
+	if ((p = strchr(host, '.')))
+	{
+		char *domain = 0;
+		char _domain[1024];
+
+		// strip off domain
+		FILE *resolv = fopen("/etc/resolv.conf", "r");
+		if (resolv)
+		{
+			char buf[1024];
+			char *b;
+
+			while (fgets(buf, sizeof(buf), resolv))
+			{
+				if (strncmp(buf, "domain", 6) && strncmp(buf, "search", 6))
+					continue;
+
+				if (!isspace(buf[6]))
+					continue;
+
+				b = buf + 7;
+				while (isspace(*b)) b++;
+
+				if (*b)
+				{
+					char *d = b;
+					while (*b && !isspace(*b)) b++;
+					*b = 0;
+					if (buf[0] == 'd') // domain is canonical
+					{
+						domain = d;
+						break;
+					}
+
+					// first search line
+					if (!domain)
+					{
+						// hold, may be subsequent domain line
+						strncpy(_domain, d, sizeof(_domain))[sizeof(_domain)-1] = 0;
+						domain = _domain;
+					}
+				}
+			}
+
+			fclose(resolv);
+		}
+
+		if (domain)
+		{
+			int hl = strlen(host);
+			int dl = strlen(domain);
+			if (dl < hl && host[hl - dl - 1] == '.' && !strcmp(host + hl - dl, domain))
+				host[hl -dl - 1] = 0;
+		}
+		else
+		{
+			*p = 0; // everything after first dot
+		}
+	}
+}
+
+// Init data structures
+static void initdata(int optdebug, char *optconfig)
+{
+	int i;
+
+	if (!(_statistics = shared_malloc(sizeof(struct Tstats))))
+	{
+		LOG(0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno));
+		exit(1);
+	}
+	if (!(config = shared_malloc(sizeof(configt))))
+	{
+		LOG(0, 0, 0, "Error doing malloc for configuration: %s\n", strerror(errno));
+		exit(1);
+	}
+	memset(config, 0, sizeof(configt));
+	time(&config->start_time);
+	strncpy(config->config_file, optconfig, strlen(optconfig));
+	config->debug = optdebug;
+	config->num_tbfs = MAXTBFS;
+	config->rl_rate = 28; // 28kbps
+
+	if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)))
+	{
+		LOG(0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno));
+		exit(1);
+	}
+	if (!(session = shared_malloc(sizeof(sessiont) * MAXSESSION)))
+	{
+		LOG(0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno));
+		exit(1);
+	}
+
+	if (!(sess_count = shared_malloc(sizeof(sessioncountt) * MAXSESSION)))
+	{
+		LOG(0, 0, 0, "Error doing malloc for sessions_count: %s\n", strerror(errno));
+		exit(1);
+	}
+
+	if (!(radius = shared_malloc(sizeof(radiust) * MAXRADIUS)))
+	{
+		LOG(0, 0, 0, "Error doing malloc for radius: %s\n", strerror(errno));
+		exit(1);
+	}
+
+	if (!(ip_address_pool = shared_malloc(sizeof(ippoolt) * MAXIPPOOL)))
+	{
+		LOG(0, 0, 0, "Error doing malloc for ip_address_pool: %s\n", strerror(errno));
+		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);
+
+#ifdef RINGBUFFER
+	if (!(ringbuffer = shared_malloc(sizeof(struct Tringbuffer))))
+	{
+		LOG(0, 0, 0, "Error doing malloc for ringbuffer: %s\n", strerror(errno));
+		exit(1);
+	}
+	memset(ringbuffer, 0, sizeof(struct Tringbuffer));
+#endif
+
+	if (!(cli_session_actions = shared_malloc(sizeof(struct cli_session_actions) * MAXSESSION)))
+	{
+		LOG(0, 0, 0, "Error doing malloc for cli session actions: %s\n", strerror(errno));
+		exit(1);
+	}
+	memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
+
+	if (!(cli_tunnel_actions = shared_malloc(sizeof(struct cli_tunnel_actions) * MAXSESSION)))
+	{
+		LOG(0, 0, 0, "Error doing malloc for cli tunnel actions: %s\n", strerror(errno));
+		exit(1);
+	}
+	memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
+
+	memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
 	memset(session, 0, sizeof(sessiont) * MAXSESSION);
 	memset(radius, 0, sizeof(radiust) * MAXRADIUS);
 	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++)
+	{
 		session[i].next = i + 1;
+		session[i].tunnel = T_UNDEF;	// mark it as not filled in.
+	}
 	session[MAXSESSION - 1].next = 0;
 	sessionfree = 1;
+
+		// Mark all the tunnels as undefined (waiting to be filled in by a download).
+	for (i = 1; i < MAXTUNNEL- 1; i++)
+		tunnel[i].state = TUNNELUNDEF;	// mark it as not filled in.
+
 	if (!*hostname)
 	{
-		char *p;
 		// Grab my hostname unless it's been specified
 		gethostname(hostname, sizeof(hostname));
-		{
-			struct hostent *h = gethostbyname(hostname);
-			if (h)
-				myip = ntohl(*(u32 *) h->h_addr);
-		}
-
-		if ((p = strstr(hostname, ".optusnet.com.au"))) *p = 0;
+		stripdomain(hostname);
 	}
+
 	_statistics->start_time = _statistics->last_reset = time(NULL);
-}
 
-void initiptables(void)
-{
-	/* Flush the tables here so that we have a clean slate */
-	system("iptables -t nat -F l2tpns");
-	system("iptables -t mangle -F l2tpns");
+#ifdef BGP
+	if (!(bgp_peers = shared_malloc(sizeof(struct bgp_peer) * BGP_NUM_PEERS)))
+	{
+		LOG(0, 0, 0, "Error doing malloc for bgp: %s\n", strerror(errno));
+		exit(1);
+	}
+#endif /* BGP */
 }
 
-int assign_ip_address(sessionidt s)
+static int assign_ip_address(sessionidt s)
 {
-	unsigned i;
+	u32 i;
 	int best = -1;
-	clockt best_time = time_now;
+	time_t best_time = time_now;
 	char *u = session[s].user;
 	char reuse = 0;
 
-#ifdef STAT_CALLS
-	STAT(call_assign_ip_address);
-#endif
-	for (i = 0; i < ip_pool_size; i++)
+
+	CSTAT(call_assign_ip_address);
+
+	for (i = 1; i < ip_pool_size; i++)
 	{
 		if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
 			continue;
@@ -1987,14 +2682,15 @@ int assign_ip_address(sessionidt s)
 
 	if (best < 0)
 	{
-		log(0, 0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
+		LOG(0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
 		return 0;
 	}
 
-	session[s].ip = ntohl(ip_address_pool[best].address);
+	session[s].ip = ip_address_pool[best].address;
 	session[s].ip_pool_index = best;
 	ip_address_pool[best].assigned = 1;
 	ip_address_pool[best].last = time_now;
+	ip_address_pool[best].session = s;
 	if (session[s].walled_garden)
 		/* Don't track addresses of users in walled garden (note: this
 		   means that their address isn't "sticky" even if they get
@@ -2004,49 +2700,164 @@ int assign_ip_address(sessionidt s)
 		strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
 
 	STAT(ip_allocated);
-	log(4, ip_address_pool[best].address, s, session[s].tunnel,
-		"assign_ip_address(): %s ip address %lu from pool\n", reuse ? "Reusing" : "Allocating", best);
+	LOG(4, s, session[s].tunnel, "assign_ip_address(): %s ip address %d from pool\n",
+		reuse ? "Reusing" : "Allocating", best);
 
 	return 1;
 }
 
-void free_ip_address(sessionidt s)
+static void free_ip_address(sessionidt s)
 {
 	int i = session[s].ip_pool_index;
 
-#ifdef STAT_CALLS
-	STAT(call_free_ip_address);
-#endif
+
+	CSTAT(call_free_ip_address);
 
 	if (!session[s].ip)
 		return; // what the?
 
+	if (i < 0)	// Is this actually part of the ip pool?
+		i = 0;
+
 	STAT(ip_freed);
-	uncache_sessionid(session[s].ip);
+	cache_ipmap(session[s].ip, -i);	// Change the mapping to point back to the ip pool index.
 	session[s].ip = 0;
 	ip_address_pool[i].assigned = 0;
+	ip_address_pool[i].session = 0;
 	ip_address_pool[i].last = time_now;
 }
 
+//
+// Fsck the address pool against the session table.
+// Normally only called when we become a master.
+//
+// This isn't perfect: We aren't keep tracking of which
+// users used to have an IP address.
+//
+void rebuild_address_pool(void)
+{
+	int i;
+
+		//
+		// Zero the IP pool allocation, and build
+		// a map from IP address to pool index.
+	for (i = 1; i < MAXIPPOOL; ++i)
+	{
+		ip_address_pool[i].assigned = 0;
+		ip_address_pool[i].session = 0;
+		if (!ip_address_pool[i].address)
+			continue;
+
+		cache_ipmap(ip_address_pool[i].address, -i);	// Map pool IP to pool index.
+	}
+
+	for (i = 0; i < MAXSESSION; ++i)
+	{
+		int ipid;
+		if (!session[i].ip || !session[i].tunnel)
+			continue;
+		ipid = - lookup_ipmap(htonl(session[i].ip));
+
+		if (session[i].ip_pool_index < 0)
+		{
+			// Not allocated out of the pool.
+			if (ipid < 1)			// Not found in the pool either? good.
+				continue;
+
+			LOG(0, i, 0, "Session %d has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
+				i, fmtaddr(session[i].ip, 0), ipid);
+
+			// Fall through and process it as part of the pool.
+		}
+
+
+		if (ipid > MAXIPPOOL || ipid < 0)
+		{
+			LOG(0, i, 0, "Session %d has a pool IP that's not found in the pool! (%d)\n", i, ipid);
+			ipid = -1;
+			session[i].ip_pool_index = ipid;
+			continue;
+		}
+
+		ip_address_pool[ipid].assigned = 1;
+		ip_address_pool[ipid].session = i;
+		ip_address_pool[ipid].last = time_now;
+		strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
+		session[i].ip_pool_index = ipid;
+		cache_ipmap(session[i].ip, i);	// Fix the ip map.
+	}
+}
+
+//
+// Fix the address pool to match a changed session.
+// (usually when the master sends us an update).
+static void fix_address_pool(int sid)
+{
+	int ipid;
+
+	ipid = session[sid].ip_pool_index;
+
+	if (ipid > ip_pool_size)
+		return;		// Ignore it. rebuild_address_pool will fix it up.
+
+	if (ip_address_pool[ipid].address != session[sid].ip)
+		return;		// Just ignore it. rebuild_address_pool will take care of it.
+
+	ip_address_pool[ipid].assigned = 1;
+	ip_address_pool[ipid].session = sid;
+	ip_address_pool[ipid].last = time_now;
+	strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
+}
+
+//
+// Add a block of addresses to the IP pool to hand out.
+//
+static void add_to_ip_pool(u32 addr, u32 mask)
+{
+	int i;
+	if (mask == 0)
+		mask = 0xffffffff;	// Host route only.
+
+	addr &= mask;
+
+	if (ip_pool_size >= MAXIPPOOL)	// Pool is full!
+		return ;
+
+	for (i = addr ;(i & mask) == addr; ++i)
+	{
+		if ((i & 0xff) == 0 || (i&0xff) == 255)
+			continue;	// Skip 0 and broadcast addresses.
+
+		ip_address_pool[ip_pool_size].address = i;
+		ip_address_pool[ip_pool_size].assigned = 0;
+		++ip_pool_size;
+		if (ip_pool_size >= MAXIPPOOL)
+		{
+			LOG(0, 0, 0, "Overflowed IP pool adding %s\n", fmtaddr(htonl(addr), 0));
+			return;
+		}
+	}
+}
+
 // Initialize the IP address pool
-void initippool()
+static void initippool()
 {
 	FILE *f;
-	char *buf, *p;
-	int pi = 0;
+	char *p;
+	char buf[4096];
 	memset(ip_address_pool, 0, sizeof(ip_address_pool));
 
 	if (!(f = fopen(IPPOOLFILE, "r")))
 	{
-		log(0, 0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
-		exit(-1);
+		LOG(0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
+		exit(1);
 	}
 
-	buf = (char *)malloc(4096);
-
-	while (pi < MAXIPPOOL && fgets(buf, 4096, f))
+	while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
 	{
-		char* pool = buf;
+		char *pool = buf;
+		buf[4095] = 0;	// Force it to be zero terminated/
+
 		if (*buf == '#' || *buf == '\n')
 			continue; // Skip comments / blank lines
 		if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
@@ -2057,8 +2868,8 @@ void initippool()
 			src = inet_addr(buf);
 			if (src == INADDR_NONE)
 			{
-				log(0, 0, 0, 0, "Invalid address pool IP %s", buf);
-				exit(-1);
+				LOG(0, 0, 0, "Invalid address pool IP %s\n", buf);
+				exit(1);
 			}
 			// This entry is for a specific IP only
 			if (src != config->bind_address)
@@ -2070,210 +2881,244 @@ void initippool()
 		{
 			// It's a range
 			int numbits = 0;
-			unsigned long start = 0, end = 0, mask = 0, ip;
-			struct rtentry r;
+			u32 start = 0, mask = 0;
 
-			log(2, 0, 0, 0, "Adding IP address range %s\n", buf);
+			LOG(2, 0, 0, "Adding IP address range %s\n", buf);
 			*p++ = 0;
 			if (!*p || !(numbits = atoi(p)))
 			{
-				log(0, 0, 0, 0, "Invalid pool range %s/\n", buf, p);
+				LOG(0, 0, 0, "Invalid pool range %s\n", buf);
 				continue;
 			}
-			start = end = ntohl(inet_addr(pool));
-			mask = (unsigned long)(pow(2, numbits) - 1) << (32 - numbits);
-			start &= mask;
-			end = start + (int)(pow(2, (32 - numbits))) - 1;
-			for (ip = (start + 1); ip < end && pi < MAXIPPOOL; ip++)
-			{
-				if ((ip & 0xFF) == 0 || (ip & 0xFF) == 255)
-					continue;
-				ip_address_pool[pi++].address = htonl(ip);
-			}
+			start = ntohl(inet_addr(pool));
+			mask = (u32)(pow(2, numbits) - 1) << (32 - numbits);
 
 			// Add a static route for this pool
-			log(5, 0, 0, 0, "Adding route for address pool %s/%d\n", inet_toa(htonl(start)), 32+mask);
-			memset(&r, 0, sizeof(r));
-			r.rt_dev = config->tapdevice;
-			r.rt_dst.sa_family = AF_INET;
-			*(u32 *) & (((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr) = htonl(start);
-			r.rt_genmask.sa_family = AF_INET;
-			*(u32 *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask);
-			r.rt_flags = (RTF_UP | RTF_STATIC);
-			if (ioctl(ifrfd, SIOCADDRT, (void *) &r) < 0)
-			{
-				log(0, 0, 0, 0, "Error adding ip address pool route %s/%d: %s\n", inet_toa(start), mask, strerror(errno));
-			}
+			LOG(5, 0, 0, "Adding route for address pool %s/%u\n",
+				fmtaddr(htonl(start), 0), 32 + mask);
+
+			routeset(0, start, mask, 0, 1);
+
+			add_to_ip_pool(start, mask);
 		}
 		else
 		{
 			// It's a single ip address
-			ip_address_pool[pi++].address = inet_addr(pool);
+			add_to_ip_pool(inet_addr(pool), 0);
 		}
 	}
-
-	free(buf);
 	fclose(f);
-	log(1, 0, 0, 0, "IP address pool is %d addresses\n", pi);
-	ip_pool_size = pi;
+	LOG(1, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
 }
 
-void snoop_send_packet(char *packet, u16 size)
+void snoop_send_packet(char *packet, u16 size, ipt destination, u16 port)
 {
-	if (!snoop_addr.sin_port || snoopfd <= 0 || size <= 0 || !packet)
+	struct sockaddr_in snoop_addr = {0};
+	if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
 		return;
 
-	log(5, 0, 0, 0, "Snooping packet at %p (%d bytes) to %s:%d\n", packet, size, inet_toa(snoop_addr.sin_addr.s_addr), htons(snoop_addr.sin_port));
+	snoop_addr.sin_family = AF_INET;
+	snoop_addr.sin_addr.s_addr = destination;
+	snoop_addr.sin_port = ntohs(port);
+
+	LOG(5, 0, 0, "Snooping packet at %p (%d bytes) to %s:%d\n",
+		packet, size, fmtaddr(snoop_addr.sin_addr.s_addr, 0),
+		htons(snoop_addr.sin_port));
+
 	if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
-		log(0, 0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
+		LOG(0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
+
 	STAT(packets_snooped);
 }
 
-void dump_acct_info()
+static void dump_acct_info()
 {
-    char filename[1024];
-    char timestr[64];
-    time_t t = time(NULL);
-    int i;
-    FILE *f = NULL;
+	char filename[1024];
+	char timestr[64];
+	time_t t = time(NULL);
+	int i;
+	FILE *f = NULL;
 
-#ifdef STAT_CALLS
-	STAT(call_dump_acct_info);
-#endif
-    strftime(timestr, 64, "%Y%m%d%H%M%S", localtime(&t));
-    snprintf(filename, 1024, "%s/%s", config->accounting_dir, timestr);
 
-    for (i = 0; i < MAXSESSION; i++)
-    {
-	if (!session[i].opened || !session[i].cin || !session[i].cout || !*session[i].user || session[i].walled_garden)
-		continue;
-	if (!f)
+	CSTAT(call_dump_acct_info);
+
+	strftime(timestr, 64, "%Y%m%d%H%M%S", localtime(&t));
+	snprintf(filename, 1024, "%s/%s", config->accounting_dir, timestr);
+
+	for (i = 0; i < MAXSESSION; i++)
+	{
+		if (!session[i].opened || !session[i].ip || !(session[i].cin || session[i].cout) || !*session[i].user || session[i].walled_garden)
+			continue;
+		if (!f)
+		{
+			time_t now = time(NULL);
+			if (!(f = fopen(filename, "w")))
+			{
+				LOG(0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
+				return ;
+			}
+			LOG(3, 0, 0, "Dumping accounting information to %s\n", filename);
+			fprintf(f, "# dslwatch.pl dump file V1.01\n"
+			        "# host: %s\n"
+			        "# time: %ld\n"
+			        "# uptime: %ld\n"
+			        "# format: username ip qos uptxoctets downrxoctets\n",
+			        hostname,
+			        now,
+			        now - basetime);
+		}
+
+		LOG(4, 0, 0, "Dumping accounting information for %s\n", session[i].user);
+		fprintf(f, "%s %s %d %u %u\n",
+		        session[i].user,						// username
+		        fmtaddr(htonl(session[i].ip), 0),				// ip
+		        (session[i].throttle_in || session[i].throttle_out) ? 2 : 1,	// qos
+		        (u32)session[i].cin,						// uptxoctets
+		        (u32)session[i].cout);						// downrxoctets
+
+		session[i].pin = session[i].cin = 0;
+		session[i].pout = session[i].cout = 0;
+	}
+
+	if (f)
+		fclose(f);
+}
+
+// Main program
+int main(int argc, char *argv[])
+{
+	int i;
+	int optdebug = 0;
+	char *optconfig = CONFIGFILE;
+
+	time(&basetime);             // start clock
+
+	// scan args
+	while ((i = getopt(argc, argv, "dvc:h:")) >= 0)
 	{
-	    time_t now = time(NULL);
-	    if (!(f = fopen(filename, "w")))
-	    {
-		    log(0, 0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
-		    return;
-	    }
-	    log(3, 0, 0, 0, "Dumping accounting information to %s\n", filename);
-	    fprintf(f, "# dslwatch.pl dump file V1.01\n"
-		"# host: %s\n"
-		"# time: %ld\n"
-		"# uptime: %ld\n"
-		"# format: username ip qos uptxoctets downrxoctets\n",
-		    hostname,
-		    now,
-		    now - basetime);
-	}
-
-	log(4, 0, 0, 0, "Dumping accounting information for %s\n", session[i].user);
-	fprintf(f, "%s %s %d %lu %lu\n",
-	    session[i].user,				// username
-	    inet_toa(htonl(session[i].ip)),		// ip
-	    (session[i].throttle) ? 2 : 1,		// qos
-	    (unsigned long)session[i].cin,		// uptxoctets
-	    (unsigned long)session[i].cout);		// downrxoctets
-
-	session[i].pin = session[i].cin = 0;
-	session[i].pout = session[i].cout = 0;
-    }
-
-    if (f) fclose(f);
-}
+		switch (i)
+		{
+		case 'd':
+			if (fork()) exit(0);
+			setsid();
+			freopen("/dev/null", "r", stdin);
+			freopen("/dev/null", "w", stdout);
+			freopen("/dev/null", "w", stderr);
+			break;
+		case 'v':
+			optdebug++;
+			break;
+		case 'c':
+			optconfig = optarg;
+			break;
+		case 'h':
+			snprintf(hostname, sizeof(hostname), "%s", optarg);
+			break;
+		default:
+			printf("Args are:\n"
+			       "\t-d\t\tDetach from terminal\n"
+			       "\t-c <file>\tConfig file\n"
+			       "\t-h <hostname>\tForce hostname\n"
+			       "\t-v\t\tDebug\n");
+
+			return (0);
+			break;
+		}
+	}
 
-// Main program
-int main(int argc, char *argv[])
-{
-	int o;
+	// Start the timer routine off
+	time(&time_now);
+	strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
+	signal(SIGALRM, sigalrm_handler);
+	siginterrupt(SIGALRM, 0);
+
+	initplugins();
+	initdata(optdebug, optconfig);
 
-	_program_name = strdup(argv[0]);
+	init_cli(hostname);
+	read_config_file();
+	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) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
 	{
 		struct rlimit rlim;
 		rlim.rlim_cur = RLIM_INFINITY;
 		rlim.rlim_max = RLIM_INFINITY;
 		// Remove the maximum core size
-		setrlimit(RLIMIT_CORE, &rlim);
+		if (setrlimit(RLIMIT_CORE, &rlim) < 0)
+			LOG(0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
+
 		// Make core dumps go to /tmp
 		chdir("/tmp");
 	}
 
-	time(&basetime);             // start clock
-	initdata();
-
-	// scan args
-	while ((o = getopt(argc, argv, "vc:h:a:")) >= 0)
+	if (config->scheduler_fifo)
 	{
-		switch (o)
+		int ret;
+		struct sched_param params = {0};
+		params.sched_priority = 1;
+
+		if (get_nprocs() < 2)
 		{
-			case 'v':
-				config->debug++;
-				break;
-			case 'c':
-				strncpy(config->config_file, optarg, sizeof(config->config_file) - 1);
-				break;
-			case 'h':
-				strncpy(hostname, optarg, 999);
-				break;
-			case 'a':
-				myip = inet_addr(optarg);
-				if (myip == INADDR_NONE) {
-					log(0, 0, 0, 0, "Invalid ip %s\n", optarg);
-					exit(-1);
-				}
-				config->bind_address = myip;
-				handle_interface = 1;
-				break;
-			case '?':
-			default:
-				printf("Args are:\n\t-c <file>\tConfig file\n\t-h <hostname>\tForce hostname\n\t-a <address>\tUse specific address\n\t-v\t\tDebug\n");
-				return (0);
-				break;
+			LOG(0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
+			config->scheduler_fifo = 0;
+		}
+		else
+		{
+			if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
+			{
+				LOG(1, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
+			}
+			else
+			{
+				LOG(0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
+				config->scheduler_fifo = 0;
+			}
 		}
 	}
 
-	// Start the timer routine off
-	time(&time_now);
-	strftime(time_now_string, 64, "%Y-%m-%d %H:%M:%S", localtime(&time_now));
-
-	initiptables();
-	initplugins();
-	init_cli();
-	read_config_file();
-	log(1, 0, 0, 0, "L2TPNS Version 1.1.0 - http://l2tpns.sourceforge.net/\n");
-	log(1, 0, 0, 0, "Licensed under the GPL\n");
+	/* Set up the cluster communications port. */
+	if (cluster_init() < 0)
+		exit(1);
 
-	/* Start up the cluster first, so that we don't have two machines with
-	 * the same IP at once.
-	 * This is still racy, but the second GARP should fix that
-	 */
-	cluster_init(config->bind_address, 0);
-	cluster_send_message(config->cluster_address, config->bind_address, C_HELLO, hostname, strlen(hostname));
+#ifdef BGP
+	signal(SIGPIPE, SIG_IGN);
+	bgp_setup(config->as_number);
+	bgp_add_route(config->bind_address, 0xffffffff);
+	for (i = 0; i < BGP_NUM_PEERS; i++)
+	{
+		if (config->neighbour[i].name[0])
+			bgp_start(&bgp_peers[i], config->neighbour[i].name,
+				config->neighbour[i].as, config->neighbour[i].keepalive,
+				config->neighbour[i].hold, 0); /* 0 = routing disabled */
+	}
+#endif /* BGP */
 
-	inittap();
-	log(1, 0, 0, 0, "Set up on interface %s\n", config->tapdevice);
+	inittun();
+	LOG(1, 0, 0, "Set up on interface %s\n", config->tundevice);
 
 	initudp();
 	initrad();
 	initippool();
-	init_rl();
-	if (handle_interface) {
-		send_garp(config->bind_address);
-	}
-
-	// If NOSTATEFILE exists, we will ignore any updates from the cluster master for this execution
-	if (!unlink(NOSTATEFILE))
-	    config->ignore_cluster_updates = 1;
 
 	read_state();
 
-	signal(SIGALRM, sigalrm_handler);
 	signal(SIGHUP, sighup_handler);
 	signal(SIGTERM, sigterm_handler);
 	signal(SIGINT, sigterm_handler);
 	signal(SIGQUIT, sigquit_handler);
 	signal(SIGCHLD, sigchild_handler);
-	signal(SIGSEGV, sigsegv_handler);
+
+	// Prevent us from getting paged out
+	if (config->lock_pages)
+	{
+		if (!mlockall(MCL_CURRENT))
+			LOG(1, 0, 0, "Locking pages into memory\n");
+		else
+			LOG(0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
+	}
 
 	alarm(1);
 
@@ -2282,10 +3127,29 @@ int main(int argc, char *argv[])
 		setuid(config->target_uid);
 
 	mainloop();
+
+#ifdef BGP
+	/* try to shut BGP down cleanly; with luck the sockets will be
+	   writable since we're out of the select */
+	for (i = 0; i < BGP_NUM_PEERS; i++)
+		if (bgp_peers[i].state == Established)
+			bgp_stop(&bgp_peers[i]);
+#endif /* BGP */
+
+	/* remove plugins (so cleanup code gets run) */
+	plugins_done();
+
+	// Remove the PID file if we wrote it
+	if (config->wrote_pid && *config->pid_file == '/')
+		unlink(config->pid_file);
+
+	/* kill CLI children */
+	signal(SIGTERM, SIG_IGN);
+	kill(0, SIGTERM);
 	return 0;
 }
 
-void sighup_handler(int junk)
+static void sighup_handler(int sig)
 {
 	if (log_stream && log_stream != stderr)
 	{
@@ -2296,12 +3160,12 @@ void sighup_handler(int junk)
 	read_config_file();
 }
 
-void sigalrm_handler(int junk)
+static void sigalrm_handler(int sig)
 {
 	// Log current traffic stats
 
 	snprintf(config->bandwidth, sizeof(config->bandwidth),
-		"UDP-ETH:%1.0f/%1.0f  ETH-UDP:%1.0f/%1.0f  TOTAL:%0.1f   IN:%lu OUT:%lu",
+		"UDP-ETH:%1.0f/%1.0f  ETH-UDP:%1.0f/%1.0f  TOTAL:%0.1f   IN:%u OUT:%u",
 		(udp_rx / 1024.0 / 1024.0 * 8),
 		(eth_tx / 1024.0 / 1024.0 * 8),
 		(eth_rx / 1024.0 / 1024.0 * 8),
@@ -2318,7 +3182,7 @@ void sigalrm_handler(int junk)
 
 	// Update the internal time counter
 	time(&time_now);
-	strftime(time_now_string, 64, "%Y-%m-%d %H:%M:%S", localtime(&time_now));
+	strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
 	alarm(1);
 
 	{
@@ -2329,20 +3193,20 @@ void sigalrm_handler(int junk)
 
 }
 
-void sigterm_handler(int junk)
+static void sigterm_handler(int sig)
 {
-	log(1, 0, 0, 0, "Shutting down cleanly\n");
+	LOG(1, 0, 0, "Shutting down cleanly\n");
 	if (config->save_state)
 		dump_state();
+
 	main_quit++;
 }
 
-void sigquit_handler(int junk)
+static void sigquit_handler(int sig)
 {
-	FILE *f;
 	int i;
 
-	log(1, 0, 0, 0, "Shutting down without saving sessions\n");
+	LOG(1, 0, 0, "Shutting down without saving sessions\n");
 	for (i = 1; i < MAXSESSION; i++)
 	{
 		if (session[i].opened)
@@ -2354,208 +3218,203 @@ void sigquit_handler(int junk)
 			tunnelshutdown(i, "L2TPNS Closing");
 	}
 
-	cluster_send_goodbye();
-
-	// Touch a file which says not to reload the state
-	f = fopen(NOSTATEFILE, "w");
-	if (f) fclose(f);
-
 	main_quit++;
 }
 
-void sigchild_handler(int signal)
+static void sigchild_handler(int sig)
 {
 	while (waitpid(-1, NULL, WNOHANG) > 0)
 	    ;
 }
 
-void sigsegv_handler(int signal)
+static void read_state()
 {
-	log(0, 0, 0, 0, "----------------------------------------------\n");
-	log(0, 0, 0, 0, "- SEGFAULT!                                  -\n");
-	log(0, 0, 0, 0, "----------------------------------------------\n");
-	_exit(0);
-}
+	struct stat sb;
+	int i;
+	ippoolt itmp;
+	FILE *f;
+	char magic[sizeof(DUMP_MAGIC) - 1];
+	u32 buf[2];
 
-void read_state()
-{
-    struct stat sb;
-    int i;
-    ippoolt itmp;
-    FILE *f;
-    char magic[sizeof(DUMP_MAGIC)-1];
-    u32 buf[2];
+	if (!config->save_state)
+	{
+		unlink(STATEFILE);
+		return ;
+	}
 
-    if (!config->save_state)
-	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 ;
+	}
 
-    // Ignore saved state if NOSTATEFILE exists
-    if (config->ignore_cluster_updates)
-    {
+	f = fopen(STATEFILE, "r");
 	unlink(STATEFILE);
-	return;
-    }
 
-    if (stat(STATEFILE, &sb) < 0)
-	return;
+	if (!f)
+	{
+		LOG(0, 0, 0, "Can't read state file: %s\n", strerror(errno));
+		exit(1);
+	}
 
-    if (sb.st_mtime < (time(NULL) - 60))
-    {
-	log(0, 0, 0, 0, "State file is too old to read, ignoring\n");
-	unlink(STATEFILE);
-	return;
-    }
+	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);
+	}
 
-    f = fopen(STATEFILE, "r");
-    unlink(STATEFILE);
+	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 (!f)
-    {
-	log(0, 0, 0, 0, "Can't read state file: %s\n", strerror(errno));
-	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);
+	}
 
-    if (fread(magic, sizeof(magic), 1, f) != 1 || strncmp(magic, DUMP_MAGIC, sizeof(magic)))
-    {
-	log(0, 0, 0, 0, "Bad state file magic\n");
-	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);
+		}
 
-    log(1, 0, 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, 0, "Error/mismatch reading ip pool header from state file\n");
-	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);
+		}
 
-    if (buf[0] > ip_pool_size)
-    {
-	log(0, 0, 0, 0, "ip pool has shrunk!  state = %d, current = %d\n", buf[0], ip_pool_size);
-	exit(1);
-    }
+		memcpy(&ip_address_pool[i], &itmp, sizeof(itmp));
+	}
 
-    log(2, 0, 0, 0, "Loading %u ip addresses\n", buf[0]);
-    for (i = 0; i < buf[0]; i++)
-    {
-	if (fread(&itmp, sizeof(itmp), 1, f) != 1)
+	if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] != MAXTUNNEL || buf[1] != sizeof(tunnelt))
 	{
-	    log(0, 0, 0, 0, "Error reading ip %d from state file: %s\n", i, strerror(errno));
-	    exit(1);
+		LOG(0, 0, 0, "Error/mismatch reading tunnel header from state file\n");
+		exit(1);
 	}
 
-	if (itmp.address != ip_address_pool[i].address)
+	LOG(2, 0, 0, "Loading %u tunnels\n", MAXTUNNEL);
+	if (fread(tunnel, sizeof(tunnelt), MAXTUNNEL, f) != MAXTUNNEL)
 	{
-	    log(0, 0, 0, 0, "Mismatched ip %d from state file: pool may only be extended\n", i);
-	    exit(1);
+		LOG(0, 0, 0, "Error reading tunnel data from state file\n");
+		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, 0, "Error/mismatch reading tunnel header 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);
+	}
 
-    log(2, 0, 0, 0, "Loading %u tunnels\n", MAXTUNNEL);
-    if (fread(tunnel, sizeof(tunnelt), MAXTUNNEL, f) != MAXTUNNEL)
-    {
-	log(0, 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, 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, 0, "Error/mismatch reading session header from state file\n");
-	exit(1);
-    }
+	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, 0, "Loading %u sessions\n", MAXSESSION);
-    if (fread(session, sizeof(sessiont), MAXSESSION, f) != MAXSESSION)
-    {
-	log(0, 0, 0, 0, "Error reading session data 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 = 0;
-	session[i].throttle = 0;
-	if (session[i].opened)
+	for (i = 0; i < MAXSESSION; i++)
 	{
-	    log(2, 0, i, 0, "Loaded active session for user %s\n", session[i].user);
-	    if (session[i].ip && session[i].ip != 0xFFFFFFFE)
-		sessionsetup(session[i].tunnel, i, 0);
+		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, 0, "Loaded saved state information\n");
+	fclose(f);
+	LOG(0, 0, 0, "Loaded saved state information\n");
 }
 
-void dump_state()
+static void dump_state()
 {
-    FILE *f;
-    u32 buf[2];
+	FILE *f;
+	u32 buf[2];
 
-    if (!config->save_state)
-	return;
+	if (!config->save_state)
+		return;
 
-    do {
-	if (!(f = fopen(STATEFILE, "w")))
-	    break;
+	do
+	{
+		if (!(f = fopen(STATEFILE, "w")))
+			break;
 
-	log(1, 0, 0, 0, "Dumping state information\n");
+		LOG(1, 0, 0, "Dumping state information\n");
 
-	if (fwrite(DUMP_MAGIC, sizeof(DUMP_MAGIC)-1, 1, f) != 1) break;
+		if (fwrite(DUMP_MAGIC, sizeof(DUMP_MAGIC) - 1, 1, f) != 1)
+			break;
 
-	log(2, 0, 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 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, 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 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, 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;
+		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);
+		if (fclose(f) == 0)
+			return ; // OK
+	}
+	while (0);
 
-    log(0, 0, 0, 0, "Can't write state information: %s\n", strerror(errno));
-    unlink(STATEFILE);
+	LOG(0, 0, 0, "Can't write state information: %s\n", strerror(errno));
+	unlink(STATEFILE);
 }
 
-void build_chap_response(char *challenge, u8 id, u16 challenge_length, char **challenge_response)
+static void build_chap_response(char *challenge, u8 id, u16 challenge_length, char **challenge_response)
 {
 	MD5_CTX ctx;
 	*challenge_response = NULL;
 
 	if (!*config->l2tpsecret)
 	{
-		log(0, 0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
+		LOG(0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
 		return;
 	}
 
-	log(4, 0, 0, 0, "   Building challenge response for CHAP request\n");
+	LOG(4, 0, 0, "   Building challenge response for CHAP request\n");
 
 	*challenge_response = (char *)calloc(17, 1);
 
@@ -2570,22 +3429,20 @@ void build_chap_response(char *challenge, u8 id, u16 challenge_length, char **ch
 
 static int facility_value(char *name)
 {
-    int i;
-    for (i = 0; facilitynames[i].c_name; i++)
-    {
-	if (strcmp(facilitynames[i].c_name, name) == 0)
-	    return facilitynames[i].c_val;
-    }
-    return 0;
+	int i;
+	for (i = 0; facilitynames[i].c_name; i++)
+	{
+		if (strcmp(facilitynames[i].c_name, name) == 0)
+			return facilitynames[i].c_val;
+	}
+	return 0;
 }
 
-void update_config()
+static void update_config()
 {
 	int i;
-
-	snoop_addr.sin_family = AF_INET;
-	snoop_addr.sin_addr.s_addr = config->snoop_destination_host;
-	snoop_addr.sin_port = htons(config->snoop_destination_port);
+	static int timeout = 0;
+	static int interval = 0;
 
 	// Update logging
 	closelog();
@@ -2597,9 +3454,18 @@ void update_config()
 	}
 	if (*config->log_filename)
 	{
-		if (strstr(config->log_filename, "file:") == config->log_filename)
+		if (strstr(config->log_filename, "syslog:") == config->log_filename)
+		{
+			char *p = config->log_filename + 7;
+			if (*p)
+			{
+				openlog("l2tpns", LOG_PID, facility_value(p));
+				syslog_log = 1;
+			}
+		}
+		else if (strchr(config->log_filename, '/') == config->log_filename)
 		{
-			if ((log_stream = fopen((char *)(config->log_filename + 5), "a")))
+			if ((log_stream = fopen((char *)(config->log_filename), "a")))
 			{
 				fseek(log_stream, 0, SEEK_END);
 				setbuf(log_stream, NULL);
@@ -2610,15 +3476,6 @@ void update_config()
 				setbuf(log_stream, NULL);
 			}
 		}
-		else if (strstr(config->log_filename, "syslog:") == config->log_filename)
-		{
-			char *p = config->log_filename + 7;
-			if (*p)
-			{
-				openlog("l2tpns", LOG_PID, facility_value(p));
-				syslog_log = 1;
-			}
-		}
 	}
 	else
 	{
@@ -2630,18 +3487,33 @@ void update_config()
 	// Update radius
 	config->numradiusservers = 0;
 	for (i = 0; i < MAXRADSERVER; i++)
-		if (config->radiusserver[i]) config->numradiusservers++;
+		if (config->radiusserver[i])
+		{
+			config->numradiusservers++;
+			// Set radius port: if not set, take the port from the
+			// first radius server.  For the first radius server,
+			// take the #defined default value from l2tpns.h
+
+			// test twice, In case someone works with
+			// a secondary radius server without defining
+			// a primary one, this will work even then.
+			if (i>0 && !config->radiusport[i])
+				config->radiusport[i] = config->radiusport[i-1];
+			if (!config->radiusport[i])
+				config->radiusport[i] = RADPORT;
+		}
 
 	if (!config->numradiusservers)
-	{
-		log(0, 0, 0, 0, "No RADIUS servers defined!\n");
-	}
+		LOG(0, 0, 0, "No RADIUS servers defined!\n");
+
+	config->num_radfds = 2 << RADIUS_SHIFT;
 
 	// Update plugins
 	for (i = 0; i < MAXPLUGINS; i++)
 	{
 		if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
 			continue;
+
 		if (*config->plugins[i])
 		{
 			// Plugin added
@@ -2654,118 +3526,303 @@ void update_config()
 		}
 	}
 	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;
+	if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
+	if (!*config->cluster_interface)
+		strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
+
+	if (!config->cluster_hb_interval)
+		config->cluster_hb_interval = PING_INTERVAL;	// Heartbeat every 0.5 seconds.
+
+	if (!config->cluster_hb_timeout)
+		config->cluster_hb_timeout = HB_TIMEOUT;	// 10 missed heartbeat triggers an election.
+
+	if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
+	{
+		// Paranoia:  cluster_check_master() treats 2 x interval + 1 sec as
+		// late, ensure we're sufficiently larger than that
+		int t = 4 * config->cluster_hb_interval + 11;
+
+		if (config->cluster_hb_timeout < t)
+		{
+			LOG(0, 0, 0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
+			config->cluster_hb_timeout = t;
+		}
+
+		// Push timing changes to the slaves immediately if we're the master
+		if (config->cluster_iam_master)
+			cluster_heartbeat();
+
+		interval = config->cluster_hb_interval;
+		timeout = config->cluster_hb_timeout;
+	}
+
+	// Write PID file
+	if (*config->pid_file == '/' && !config->wrote_pid)
+	{
+		FILE *f;
+		if ((f = fopen(config->pid_file, "w")))
+		{
+			fprintf(f, "%d\n", getpid());
+			fclose(f);
+			config->wrote_pid = 1;
+		}
+		else
+		{
+			LOG(0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
+		}
+	}
+
 	config->reload_config = 0;
 }
 
-void read_config_file()
+static void read_config_file()
 {
 	FILE *f;
 
 	if (!config->config_file) return;
-	if (!(f = fopen(config->config_file, "r"))) {
+	if (!(f = fopen(config->config_file, "r")))
+	{
 		fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
 		return;
 	}
 
-	log(3, 0, 0, 0, "Reading config file %s\n", config->config_file);
+	LOG(3, 0, 0, "Reading config file %s\n", config->config_file);
 	cli_do_file(f);
-	log(3, 0, 0, 0, "Done reading config file\n");
+	LOG(3, 0, 0, "Done reading config file\n");
 	fclose(f);
 	update_config();
-	log_stream = NULL;
 }
 
-int sessionsetup(tunnelidt t, sessionidt s, u8 routes)
+int sessionsetup(tunnelidt t, sessionidt s)
 {
 	// A session now exists, set it up
 	ipt ip;
 	char *user;
 	sessionidt i;
-#ifdef STAT_CALLS
-	STAT(call_sessionsetup);
-#endif
-	log(3, session[s].ip, s, t, "Doing session setup for session\n");
-	if (!session[s].ip) {
-		log(0, session[s].ip, s, t, "VERY VERY BAD! sessionsetup() called with no session[s].ip\n");
-		return 1;
+	int r;
+
+	CSTAT(call_sessionsetup);
+
+	LOG(3, s, t, "Doing session setup for session\n");
+
+	if (!session[s].ip || session[s].ip == 0xFFFFFFFE)
+	{
+		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");
+			return 0;
+		}
+		LOG(3, s, t, "   No IP allocated. Assigned %s from pool\n",
+			fmtaddr(htonl(session[s].ip), 0));
 	}
 
+
 	// Make sure this is right
 	session[s].tunnel = t;
+
 	// zap old sessions with same IP and/or username
-	// Don't kill walled garden sessions - doing so leads to a DoS
+	// Don't kill gardened sessions - doing so leads to a DoS
 	// from someone who doesn't need to know the password
-	ip = session[s].ip;
-	user = session[s].user;
-	for (i = 1; i < MAXSESSION; i++)
 	{
-		if (i == s) continue;
-		if (ip == session[i].ip) sessionkill(i, "Duplicate IP address");
-		if (!session[s].walled_garden && !session[i].walled_garden && strcasecmp(user, session[i].user) == 0)
-			sessionkill(i, "Duplicate session for user");
+		ip = session[s].ip;
+		user = session[s].user;
+		for (i = 1; i <= config->cluster_highest_sessionid; i++)
+		{
+			if (i == s) continue;
+			if (ip == session[i].ip) sessionkill(i, "Duplicate IP address");
+			if (!session[s].walled_garden && !session[i].walled_garden && strcasecmp(user, session[i].user) == 0)
+				sessionkill(i, "Duplicate session for users");
+		}
+	}
+
+	{
+	    	int routed = 0;
+
+		// Add the route for this session.
+		for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
+		{
+			if ((session[s].ip & session[s].route[r].mask) ==
+			    (session[s].route[r].ip & session[s].route[r].mask))
+				routed++;
+
+			routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 1);
+		}
+
+		// Static IPs need to be routed if not already
+		// 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.
+		if (session[s].ip_pool_index == -1) // static ip
+		{
+			if (!routed) routeset(s, session[s].ip, 0, 0, 1);
+		}
+		else
+			cache_ipmap(session[s].ip, s);
+	}
+
+	if (!session[s].unique_id)
+	{
+		// did this session just finish radius?
+		LOG(3, s, t, "Sending initial IPCP to client\n");
+		sendipcp(t, s);
+		session[s].unique_id = ++last_id;
+	}
+
+	// Run the plugin's against this new session.
+	{
+		struct param_new_session data = { &tunnel[t], &session[s] };
+		run_plugins(PLUGIN_NEW_SESSION, &data);
+	}
+
+	// Allocate TBFs if throttled
+	if (session[s].throttle_in || session[s].throttle_out)
+		throttle_session(s, session[s].throttle_in, session[s].throttle_out);
+
+	session[s].last_packet = time_now;
+
+	LOG(2, s, t, "Login by %s at %s from %s (%s)\n", session[s].user,
+		fmtaddr(htonl(session[s].ip), 0),
+		fmtaddr(htonl(tunnel[t].ip), 1), tunnel[t].hostname);
+
+	cluster_send_session(s);	// Mark it as dirty, and needing to the flooded to the cluster.
+
+	return 1;       // RADIUS OK and IP allocated, done...
+}
+
+//
+// This session just got dropped on us by the master or something.
+// Make sure our tables up up to date...
+//
+int load_session(sessionidt s, sessiont *new)
+{
+	int i;
+	int newip = 0;
+
+		// Sanity checks.
+	if (new->ip_pool_index >= MAXIPPOOL ||
+		new->tunnel >= MAXTUNNEL)
+	{
+		LOG(0, s, 0, "Strange session update received!\n");
+			// FIXME! What to do here?
+		return 0;
+	}
+
+		//
+		// Ok. All sanity checks passed. Now we're committed to
+		// loading the new session.
+		//
+
+	session[s].tunnel = new->tunnel; // For logging in cache_ipmap
+
+	// See if routes/ip cache need updating
+	if (new->ip != session[s].ip)
+		newip++;
+
+	for (i = 0; !newip && i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
+		if (new->route[i].ip != session[s].route[i].ip ||
+		    new->route[i].mask != session[s].route[i].mask)
+			newip++;
+
+	// needs update
+	if (newip)
+	{
+	    	int routed = 0;
+
+		// remove old routes...
+		for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
+		{
+			if ((session[s].ip & session[s].route[i].mask) ==
+			    (session[s].route[i].ip & session[s].route[i].mask))
+				routed++;
+
+			routeset(s, session[s].route[i].ip, session[s].route[i].mask, 0, 0);
+		}
+
+		// ...ip
+		if (session[s].ip)
+		{
+			if (session[s].ip_pool_index == -1) // static IP
+			{
+				if (!routed) routeset(s, session[s].ip, 0, 0, 0);
+			}
+			else		// It's part of the IP pool, remove it manually.
+				uncache_ipmap(session[s].ip);
+		}
+
+		routed = 0;
+
+		// add new routes...
+		for (i = 0; i < MAXROUTE && new->route[i].ip; i++)
+		{
+			if ((new->ip & new->route[i].mask) ==
+			    (new->route[i].ip & new->route[i].mask))
+				routed++;
+
+			routeset(s, new->route[i].ip, new->route[i].mask, 0, 1);
+		}
+
+		// ...ip
+		if (new->ip)
+		{
+			// If there's a new one, add it.
+			if (new->ip_pool_index == -1)
+			{
+				if (!routed) routeset(s, new->ip, 0, 0, 1);
+			}
+			else
+				cache_ipmap(new->ip, s);
+		}
 	}
 
-	if (routes)
+	// check filters
+	if (new->filter_in && (new->filter_in > MAXFILTER || !ip_filters[new->filter_in - 1].name[0]))
 	{
-		if (session[s].route[routes].ip && session[s].route[routes].mask)
-		{
-			log(2, session[s].ip, s, t, "Routing session\n");
-			routeset(session[s].ip, 0, 0, 1);
-			while (routes--)
-				routeset(session[s].route[routes].ip, session[s].route[routes].mask,
-						session[s].ip, 1);
-		}
+		LOG(2, s, session[s].tunnel, "Dropping invalid input filter %d\n", (int) new->filter_in);
+		new->filter_in = 0;
 	}
-	sessionsendarp(s);
-	if (!session[s].sid)
-		sendipcp(t, s);
-
-	// Force throttling on or off
-	// This has the advantage of cleaning up after another throttled user who may have left
-	// firewall rules lying around
-	throttle_session(s, session[s].throttle);
 
+	if (new->filter_out && (new->filter_out > MAXFILTER || !ip_filters[new->filter_out - 1].name[0]))
 	{
-		struct param_new_session data = { &tunnel[t], &session[s] };
-		run_plugins(PLUGIN_NEW_SESSION, &data);
+		LOG(2, s, session[s].tunnel, "Dropping invalid output filter %d\n", (int) new->filter_out);
+		new->filter_out = 0;
 	}
 
-	if (!session[s].sid)
-		session[s].sid = ++last_sid;
-
-	cache_sessionid(htonl(session[s].ip), s);
+	if (new->filter_in != session[s].filter_in)
+	{
+		if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
+		if (new->filter_in)       ip_filters[new->filter_in - 1].used++;
+	}
 
-	cluster_send_session(s);
-	session[s].last_packet = time_now;
+	if (new->filter_out != session[s].filter_out)
 	{
-		char *sessionip, *tunnelip;
-		sessionip = strdup(inet_toa(ntohl(session[s].ip)));
-		tunnelip = strdup(inet_toa(ntohl(tunnel[t].ip)));
-		log(2, session[s].ip, s, t, "Login by %s at %s from %s (%s)\n",
-				session[s].user, sessionip, tunnelip, tunnel[t].hostname);
-		if (sessionip) free(sessionip);
-		if (tunnelip) free(tunnelip);
+		if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
+		if (new->filter_out)       ip_filters[new->filter_out - 1].used++;
 	}
 
-	return 1;       // RADIUS OK and IP allocated, done...
-}
+	if (new->tunnel && s > config->cluster_highest_sessionid)	// Maintain this in the slave. It's used
+					// for walking the sessions to forward byte counts to the master.
+		config->cluster_highest_sessionid = s;
 
-#ifdef RINGBUFFER
-void ringbuffer_dump(FILE *stream)
-{
-	int i = ringbuffer->head;
+	// TEMP: old session struct used a u32 to define the throttle
+	// speed for both up/down, new uses a u16 for each.  Deal with
+	// sessions from an old master for migration.
+	if (new->throttle_out == 0 && new->tbf_out)
+		new->throttle_out = new->throttle_in;
 
-	while (i != ringbuffer->tail)
-	{
-		if (*ringbuffer->buffer[i].message)
-			fprintf(stream, "%d-%s", ringbuffer->buffer[i].level, ringbuffer->buffer[i].message);
-		if (++i == ringbuffer->tail) break;
-		if (i == RINGBUFFER_SIZE) i = 0;
-	}
+	memcpy(&session[s], new, sizeof(session[s]));	// Copy over..
+
+		// Do fixups into address pool.
+	if (new->ip_pool_index != -1)
+		fix_address_pool(s);
+
+	return 1;
 }
-#endif
 
-void initplugins()
+static void initplugins()
 {
 	int i;
 
@@ -2775,211 +3832,659 @@ void initplugins()
 		plugins[i] = ll_init();
 }
 
-void add_plugin(char *plugin_name)
+static void *open_plugin(char *plugin_name, int load)
 {
-	void *p;
+	char path[256] = "";
+
+	snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
+	LOG(2, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
+	return dlopen(path, RTLD_NOW);
+}
+
+// plugin callback to get a config value
+static void *getconfig(char *key, enum config_typet type)
+{
+	int i;
+
+	for (i = 0; config_values[i].key; i++)
+	{
+		if (!strcmp(config_values[i].key, key))
+		{
+			if (config_values[i].type == type)
+				return ((void *) config) + config_values[i].offset;
+
+			LOG(1, 0, 0, "plugin requested config item \"%s\" expecting type %d, have type %d\n",
+				key, type, config_values[i].type);
+
+			return 0;
+		}
+	}
+
+	LOG(1, 0, 0, "plugin requested unknown config item \"%s\"\n", key);
+	return 0;
+}
+
+static int add_plugin(char *plugin_name)
+{
+	static struct pluginfuncs funcs = {
+		_log,
+		_log_hex,
+		fmtaddr,
+		sessionbyuser,
+		sessiontbysessionidt,
+		sessionidtbysessiont,
+		radiusnew,
+		radiussend,
+		getconfig,
+		sessionkill,
+		throttle_session,
+		cluster_send_session,
+	};
+
+	void *p = open_plugin(plugin_name, 1);
 	int (*initfunc)(struct pluginfuncs *);
-	char path[256] = {0};
 	int i;
-	struct pluginfuncs funcs;
-
-	funcs._log = _log;
-	funcs._log_hex = _log_hex;
-	funcs.inet_toa = inet_toa;
-	funcs.get_session_by_username = sessionbyuser;
-	funcs.get_session_by_id = sessiontbysessionidt;
-	funcs.get_id_by_session = sessionidtbysessiont;
-	funcs.sessionkill = sessionkill;
-	funcs.radiusnew = radiusnew;
-	funcs.radiussend = radiussend;
-
-	snprintf(path, 256, "%s/%s.so", LIBDIR, plugin_name);
-
-	log(2, 0, 0, 0, "Loading plugin from %s\n", path);
-	p = dlopen(path, RTLD_NOW);
+
 	if (!p)
 	{
-		log(1, 0, 0, 0, "   Plugin load failed: %s\n", dlerror());
-		return;
+		LOG(1, 0, 0, "   Plugin load failed: %s\n", dlerror());
+		return -1;
 	}
 
 	if (ll_contains(loaded_plugins, p))
 	{
 		dlclose(p);
-		return;
+		return 0; // already loaded
 	}
 
 	{
-		int *v = dlsym(p, "__plugin_api_version");
+		int *v = dlsym(p, "plugin_api_version");
 		if (!v || *v != PLUGIN_API_VERSION)
 		{
-			log(1, 0, 0, 0, "   Plugin load failed: API version mismatch\n", dlerror());
+			LOG(1, 0, 0, "   Plugin load failed: API version mismatch: %s\n", dlerror());
 			dlclose(p);
-			return;
+			return -1;
 		}
 	}
 
-	initfunc = dlsym(p, "plugin_init");
-	if (!initfunc)
+	if ((initfunc = dlsym(p, "plugin_init")))
 	{
-		log(1, 0, 0, 0, "   Plugin load failed: function plugin_init() does not exist.\n", dlerror());
-		dlclose(p);
-		return;
+		if (!initfunc(&funcs))
+		{
+			LOG(1, 0, 0, "   Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
+			dlclose(p);
+			return -1;
+		}
 	}
 
-	if (!initfunc(&funcs))
-	{
-		log(1, 0, 0, 0, "   Plugin load failed: plugin_init() returned FALSE.\n", dlerror());
-		dlclose(p);
-		return;
-	}
+	ll_push(loaded_plugins, p);
 
 	for (i = 0; i < max_plugin_functions; i++)
 	{
 		void *x;
-		if (!plugin_functions[i]) continue;
-		if ((x = dlsym(p, plugin_functions[i])))
+		if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
 		{
-			log(3, 0, 0, 0, "   Supports function \"%s\"\n", plugin_functions[i]);
+			LOG(3, 0, 0, "   Supports function \"%s\"\n", plugin_functions[i]);
 			ll_push(plugins[i], x);
 		}
 	}
-	log(2, 0, 0, 0, "   Loaded plugin %s\n", plugin_name);
+
+	LOG(2, 0, 0, "   Loaded plugin %s\n", plugin_name);
+	return 1;
 }
 
-void remove_plugin(char *plugin_name)
+static void run_plugin_done(void *plugin)
 {
-	void *p;
-	int (*donefunc)();
-	char path[256] = {0};
-	int i;
+	int (*donefunc)(void) = dlsym(plugin, "plugin_done");
 
-	snprintf(path, 256, "%s/%s.so", LIBDIR, plugin_name);
+	if (donefunc)
+		donefunc();
+}
 
-	log(2, 0, 0, 0, "Removing plugin %s\n", plugin_name);
-	// Get the existing pointer
-	p = dlopen(path, RTLD_LAZY);
-	if (!p) return;
+static int remove_plugin(char *plugin_name)
+{
+	void *p = open_plugin(plugin_name, 0);
+	int loaded = 0;
 
-	for (i = 0; i < max_plugin_functions; i++)
-	{
-		void *x;
-		if (!plugin_functions[i]) continue;
-		if ((x = dlsym(p, plugin_functions[i]))) ll_delete(plugins[i], x);
-	}
+	if (!p)
+		return -1;
 
 	if (ll_contains(loaded_plugins, p))
 	{
-		ll_delete(loaded_plugins, p);
+		int i;
+		for (i = 0; i < max_plugin_functions; i++)
+		{
+			void *x;
+			if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
+				ll_delete(plugins[i], x);
+		}
 
-		donefunc = dlsym(p, "plugin_done");
-		if (donefunc) donefunc();
+		ll_delete(loaded_plugins, p);
+		run_plugin_done(p);
+		loaded = 1;
 	}
 
 	dlclose(p);
-	dlclose(p);
-	log(2, 0, 0, 0, "Removed plugin %s\n", plugin_name);
+	LOG(2, 0, 0, "Removed plugin %s\n", plugin_name);
+	return loaded;
 }
 
 int run_plugins(int plugin_type, void *data)
 {
 	int (*func)(void *data);
-	if (!plugins[plugin_type] || plugin_type > max_plugin_functions) return 1;
+
+	if (!plugins[plugin_type] || plugin_type > max_plugin_functions)
+		return PLUGIN_RET_ERROR;
 
 	ll_reset(plugins[plugin_type]);
 	while ((func = ll_next(plugins[plugin_type])))
 	{
-		int rc;
-		rc = func(data);
-		if (rc == PLUGIN_RET_STOP) return 1;
-		if (rc == PLUGIN_RET_ERROR) return 0;
+		int r = func(data);
+
+		if (r != PLUGIN_RET_OK)
+			return r; // stop here
 	}
-	return 1;
+
+	return PLUGIN_RET_OK;
 }
 
-void processcontrol(u8 * buf, int len, struct sockaddr_in *addr)
+static void plugins_done()
 {
-	char *resp;
-	int l;
-	struct param_control param = { buf, len, ntohl(addr->sin_addr.s_addr), ntohs(addr->sin_port), NULL, 0, 0 };
+	void *p;
 
-	log(4, ntohl(addr->sin_addr.s_addr), 0, 0, "Received ");
-	if (log_stream)
-		dump_packet(buf, log_stream);
+	ll_reset(loaded_plugins);
+	while ((p = ll_next(loaded_plugins)))
+		run_plugin_done(p);
+}
+
+static void processcontrol(u8 * buf, int len, struct sockaddr_in *addr, int alen)
+{
+	struct nsctl request;
+	struct nsctl response;
+	int type = unpack_control(&request, buf, len);
+	int r;
+	void *p;
+
+	if (log_stream && config->debug >= 4)
+	{
+		if (type < 0)
+		{
+			LOG(4, 0, 0, "Bogus control message from %s (%d)\n",
+				fmtaddr(addr->sin_addr.s_addr, 0), type);
+		}
+		else
+		{
+			LOG(4, 0, 0, "Received [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
+			dump_control(&request, log_stream);
+		}
+	}
+
+	switch (type)
+	{
+	case NSCTL_REQ_LOAD:
+		if (request.argc != 1)
+		{
+			response.type = NSCTL_RES_ERR;
+			response.argc = 1;
+			response.argv[0] = "name of plugin required";
+		}
+		else if ((r = add_plugin(request.argv[0])) < 1)
+		{
+			response.type = NSCTL_RES_ERR;
+			response.argc = 1;
+			response.argv[0] = !r
+				? "plugin already loaded"
+				: "error loading plugin";
+		}
+		else
+		{
+			response.type = NSCTL_RES_OK;
+			response.argc = 0;
+		}
+
+		break;
+
+	case NSCTL_REQ_UNLOAD:
+		if (request.argc != 1)
+		{
+			response.type = NSCTL_RES_ERR;
+			response.argc = 1;
+			response.argv[0] = "name of plugin required";
+		}
+		else if ((r = remove_plugin(request.argv[0])) < 1)
+		{
+			response.type = NSCTL_RES_ERR;
+			response.argc = 1;
+			response.argv[0] = !r
+				? "plugin not loaded"
+				: "plugin not found";
+		}
+		else
+		{
+			response.type = NSCTL_RES_OK;
+			response.argc = 0;
+		}
+
+		break;
+
+	case NSCTL_REQ_HELP:
+		response.type = NSCTL_RES_OK;
+		response.argc = 0;
+
+		ll_reset(loaded_plugins);
+		while ((p = ll_next(loaded_plugins)))
+		{
+			char **help = dlsym(p, "plugin_control_help");
+			while (response.argc < 0xff && help && *help)
+				response.argv[response.argc++] = *help++;
+		}
+
+		break;
+
+	case NSCTL_REQ_CONTROL:
+		{
+			struct param_control param = {
+				config->cluster_iam_master,
+				request.argc,
+				request.argv,
+				0,
+				NULL,
+			};
+
+			int r = run_plugins(PLUGIN_CONTROL, &param);
+
+			if (r == PLUGIN_RET_ERROR)
+			{
+				response.type = NSCTL_RES_ERR;
+				response.argc = 1;
+				response.argv[0] = param.additional
+					? param.additional
+					: "error returned by plugin";
+			}
+			else if (r == PLUGIN_RET_NOTMASTER)
+			{
+				static char msg[] = "must be run on master: 000.000.000.000";
+
+				response.type = NSCTL_RES_ERR;
+				response.argc = 1;
+				if (config->cluster_master_address)
+				{
+					strcpy(msg + 23, fmtaddr(config->cluster_master_address, 0));
+					response.argv[0] = msg;
+				}
+				else
+				{
+				    	response.argv[0] = "must be run on master: none elected";
+				}
+			}
+			else if (!(param.response & NSCTL_RESPONSE))
+			{
+				response.type = NSCTL_RES_ERR;
+				response.argc = 1;
+				response.argv[0] = param.response
+					? "unrecognised response value from plugin"
+					: "unhandled action";
+			}
+			else
+			{
+				response.type = param.response;
+				response.argc = 0;
+				if (param.additional)
+				{
+					response.argc = 1;
+					response.argv[0] = param.additional;
+				}
+			}
+		}
 
-	resp = calloc(1400, 1);
-	l = new_packet(PKT_RESP_ERROR, resp);
-	*(int *)(resp + 6) = *(int *)(buf + 6);
+		break;
 
-	param.type = ntohs(*(short *)(buf + 2));
-	param.id = ntohl(*(int *)(buf + 6));
-	param.data_length = ntohs(*(short *)(buf + 4)) - 10;
-	param.data = (param.data_length > 0) ? (char *)(buf + 10) : NULL;
-	param.response = resp;
-	param.response_length = l;
+	default:
+		response.type = NSCTL_RES_ERR;
+		response.argc = 1;
+		response.argv[0] = "error unpacking control packet";
+	}
 
-	if (param.type == PKT_LOAD_PLUGIN && param.data_length)
+	buf = calloc(NSCTL_MAX_PKT_SZ, 1);
+	if (!buf)
 	{
-		add_plugin(param.data);
+		LOG(2, 0, 0, "Failed to allocate nsctl response\n");
+		return;
 	}
-	else if (param.type == PKT_UNLOAD_PLUGIN && param.data_length)
+
+	r = pack_control(buf, NSCTL_MAX_PKT_SZ, response.type, response.argc, response.argv);
+	if (r > 0)
 	{
-		remove_plugin(param.data);
+		sendto(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen);
+		if (log_stream && config->debug >= 4)
+		{
+			LOG(4, 0, 0, "Sent [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
+			dump_control(&response, log_stream);
+		}
 	}
 	else
+		LOG(2, 0, 0, "Failed to pack nsctl response for %s (%d)\n",
+			fmtaddr(addr->sin_addr.s_addr, 0), r);
+
+	free(buf);
+}
+
+static tunnelidt new_tunnel()
+{
+	tunnelidt i;
+	for (i = 1; i < MAXTUNNEL; i++)
+	{
+		if (tunnel[i].state == TUNNELFREE)
+		{
+			LOG(4, 0, i, "Assigning tunnel ID %d\n", i);
+			if (i > config->cluster_highest_tunnelid)
+				config->cluster_highest_tunnelid = i;
+			return i;
+		}
+	}
+	LOG(0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
+	return 0;
+}
+
+//
+// We're becoming the master. Do any required setup..
+//
+// This is principally telling all the plugins that we're
+// now a master, and telling them about all the sessions
+// that are active too..
+//
+void become_master(void)
+{
+	int s, i;
+	run_plugins(PLUGIN_BECOME_MASTER, NULL);
+
+	// running a bunch of iptables commands is slow and can cause
+	// the master to drop tunnels on takeover--kludge around the
+	// problem by forking for the moment (note: race)
+	if (!fork_and_close())
+	{
+		for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
+		{
+			if (!session[s].tunnel) // Not an in-use session.
+				continue;
+
+			run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
+		}
+		exit(0);
+	}
+
+	// add radius fds
+	for (i = 0; i < config->num_radfds; i++)
+	{
+		FD_SET(radfds[i], &readset);
+		if (radfds[i] > readset_n)
+			readset_n = radfds[i];
+	}
+}
+
+int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
+{
+	int s, i;
+	int count = 0;
+	int buckets[64];
+
+	if (CLI_HELP_REQUESTED)
+		return CLI_HELP_NO_ARGS;
+
+	time(&time_now);
+	for (i = 0; i < 64;++i) buckets[i] = 0;
+
+	for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
+	{
+		int idle;
+		if (!session[s].tunnel)
+			continue;
+
+		idle = time_now - session[s].last_packet;
+		idle /= 5 ; // In multiples of 5 seconds.
+		if (idle < 0)
+			idle = 0;
+		if (idle > 63)
+			idle = 63;
+
+		++count;
+		++buckets[idle];
+	}
+
+	for (i = 0; i < 63; ++i)
 	{
-		run_plugins(PLUGIN_CONTROL, &param);
+		cli_print(cli, "%3d seconds  : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
 	}
+	cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
+	cli_print(cli, "%d total sessions open.", count);
+	return CLI_OK;
+}
+
+int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
+{
+	int s, i;
+	int count = 0;
+	int buckets[64];
+
+	if (CLI_HELP_REQUESTED)
+		return CLI_HELP_NO_ARGS;
+
+	time(&time_now);
+	for (i = 0; i < 64;++i) buckets[i] = 0;
 
-	if (param.send_response)
+	for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
 	{
-		send_packet(controlfd, ntohl(addr->sin_addr.s_addr), ntohs(addr->sin_port), param.response, param.response_length);
-		log(4, ntohl(addr->sin_addr.s_addr), 0, 0, "Sent Control packet response\n");
+		int open = 0, d;
+		if (!session[s].tunnel)
+			continue;
+
+		d = time_now - session[s].opened;
+		if (d < 0)
+			d = 0;
+		while (d > 1 && open < 32)
+		{
+			++open;
+			d >>= 1; // half.
+		}
+		++count;
+		++buckets[open];
 	}
 
-	free(resp);
+	s = 1;
+	for (i = 0; i  < 30; ++i)
+	{
+		cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
+		s <<= 1;
+	}
+	cli_print(cli, "%d total sessions open.", count);
+	return CLI_OK;
 }
 
-/*
- * HACK
- * Go through all of the tunnels and do some cleanups
+/* 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.
  */
-void tunnel_clean()
+static int unhide_avp(u8 *avp, tunnelidt t, sessionidt s, u16 length)
 {
-	int i;
+	MD5_CTX ctx;
+	u8 *cursor;
+	u8 digest[16];
+	u8 working_vector[16];
+	uint16_t hidden_length;
+	u8 type[2];
+	size_t done, todo;
+	u8 *output;
+
+	// Find the AVP type.
+	type[0] = *(avp + 4);
+	type[1] = *(avp + 5);
+
+	// Line up with the hidden data
+	cursor = output = avp + 6;
+
+	// Compute initial pad
+	MD5Init(&ctx);
+	MD5Update(&ctx, type, 2);
+	MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
+	MD5Update(&ctx, session[s].random_vector, session[s].random_vector_length);
+	MD5Final(digest, &ctx);
 
-	log(1, 0, 0, 0, "Cleaning tunnels array\n");
+	// Get hidden length
+	hidden_length = ((uint16_t) (digest[0] ^ cursor[0])) * 256 + (uint16_t) (digest[1] ^ cursor[1]);
 
-	for (i = 1; i < MAXTUNNEL; i++)
+	// 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;
+	}
+
+	/* Decrypt remainder */
+	done = 2;
+	todo = hidden_length;
+	while (todo)
 	{
-		if (!tunnel[i].ip
-				|| !*tunnel[i].hostname
-				|| (tunnel[i].state == TUNNELDIE && tunnel[i].die >= time_now))
+		working_vector[done] = *cursor;
+		*output = digest[done] ^ *cursor;
+		++output;
+		++cursor;
+		--todo;
+		++done;
+		if (done == 16 && todo)
 		{
-			tunnelclear(i);
+			// Compute new digest
+			done = 0;
+			MD5Init(&ctx);
+			MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
+			MD5Update(&ctx, &working_vector, 16);
+			MD5Final(digest, &ctx);
 		}
 	}
+
+	return hidden_length + 6;
 }
 
-void tunnelclear(tunnelidt t)
+static int ip_filter_port(ip_filter_portt *p, portt port)
 {
-	if (!t) return;
-	memset(&tunnel[t], 0, sizeof(tunnel[t]));
-	tunnel[t].state = TUNNELFREE;
+	switch (p->op)
+	{
+	case FILTER_PORT_OP_EQ:    return port == p->port;
+	case FILTER_PORT_OP_NEQ:   return port != p->port;
+	case FILTER_PORT_OP_GT:    return port > p->port;
+	case FILTER_PORT_OP_LT:    return port < p->port;
+	case FILTER_PORT_OP_RANGE: return port >= p->port && port <= p->port2;
+	}
+
+	return 0;
 }
 
-tunnelidt new_tunnel()
+static int ip_filter_flag(u8 op, u8 sflags, u8 cflags, u8 flags)
 {
-	tunnelidt i;
-	for (i = 1; i < MAXTUNNEL; i++)
+	switch (op)
 	{
-		if (tunnel[i].state == TUNNELFREE)
-		{
-			log(4, 0, 0, i, "Assigning tunnel ID %d\n", i);
-			return i;
-		}
+	case FILTER_FLAG_OP_ANY:
+		return (flags & sflags) || (~flags & cflags);
+
+	case FILTER_FLAG_OP_ALL:
+		return (flags & sflags) == sflags && (~flags & cflags) == cflags;
+
+	case FILTER_FLAG_OP_EST:
+		return (flags & (TCP_FLAG_ACK|TCP_FLAG_RST)) && (~flags & TCP_FLAG_SYN);
 	}
-	log(0, 0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
+
 	return 0;
 }
 
+int ip_filter(u8 *buf, int len, u8 filter)
+{
+	u16 frag_offset;
+	u8 proto;
+    	ipt src_ip;
+	ipt dst_ip;
+	portt src_port = 0;
+	portt dst_port = 0;
+	u8 flags = 0;
+	ip_filter_rulet *rule;
+
+    	if (len < 20) // up to end of destination address
+		return 0;
+
+	if ((*buf >> 4) != 4) // IPv4
+		return 0;
+
+	frag_offset = ntohs(*(u16 *) (buf + 6)) & 0x1fff;
+	proto = buf[9];
+	src_ip = *(u32 *) (buf + 12);
+	dst_ip = *(u32 *) (buf + 16);
+
+	if (frag_offset == 0 && (proto == IPPROTO_TCP || proto == IPPROTO_UDP))
+	{
+		int l = (buf[0] & 0xf) * 4; // length of IP header
+		if (len < l + 4) // ports
+			return 0;
+
+		src_port = ntohs(*(u16 *) (buf + l));
+		dst_port = ntohs(*(u16 *) (buf + l + 2));
+		if (proto == IPPROTO_TCP)
+		{
+		    	if (len < l + 14) // flags
+				return 0;
+
+			flags = buf[l + 13] & 0x3f;
+		}
+	}
+
+	for (rule = ip_filters[filter].rules; rule->action; rule++)
+	{
+		if (rule->proto != IPPROTO_IP && proto != rule->proto)
+			continue;
+
+		if (rule->src_wild != INADDR_BROADCAST &&
+		    (src_ip & ~rule->src_wild) != (rule->src_ip & ~rule->src_wild))
+			continue;
+
+		if (rule->dst_wild != INADDR_BROADCAST &&
+		    (dst_ip & ~rule->dst_wild) != (rule->dst_ip & ~rule->dst_wild))
+			continue;
+
+		if (frag_offset)
+		{
+			if (!rule->frag || rule->action == FILTER_ACTION_DENY)
+				continue;
+		}
+		else
+		{
+			if (rule->frag)
+				continue;
+
+			if (proto == IPPROTO_TCP || proto == IPPROTO_UDP)
+			{
+				if (rule->src_ports.op && !ip_filter_port(&rule->src_ports, src_port))
+					continue;
+
+				if (rule->dst_ports.op && !ip_filter_port(&rule->dst_ports, dst_port))
+					continue;
+
+				if (proto == IPPROTO_TCP && rule->tcp_flag_op &&
+				    !ip_filter_flag(rule->tcp_flag_op, rule->tcp_sflags, rule->tcp_cflags, flags))
+					continue;
+			}
+		}
+
+		// matched
+		rule->counter++;
+		return rule->action == FILTER_ACTION_PERMIT;
+	}
+
+	// default deny
+    	return 0;
+}