X-Git-Url: http://git.sameswireless.fr/l2tpns.git/blobdiff_plain/bc5b25832a728dea4346782d84d63128035bcfaf..af353b1e1ea5b28df859ce5653dd5394bd7f6ec5:/l2tpns.c

diff --git a/l2tpns.c b/l2tpns.c
index c1483fc..e65a9c1 100644
--- a/l2tpns.c
+++ b/l2tpns.c
@@ -1,10 +1,10 @@
 // L2TP Network Server
 // Adrian Kennard 2002
-// Copyright (c) 2003, 2004 Optus Internet Engineering
+// Copyright (c) 2003, 2004, 2005 Optus Internet Engineering
 // Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced
 // vim: sw=8 ts=8
 
-char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.60 2004/11/29 02:17:17 bodea Exp $";
+char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.73.2.5 2005/02/14 06:00:57 bodea Exp $";
 
 #include <arpa/inet.h>
 #include <assert.h>
@@ -64,11 +64,11 @@ 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.
-static u32 sessionid = 0;	// session id for radius accounting
+static uint32_t sessionid = 0;	// session id for radius accounting
 static int syslog_log = 0;	// are we logging to syslog
 static FILE *log_stream = NULL;	// file handle for direct logging (i.e. direct into file, not via syslog).
 extern int cluster_sockfd;	// Intra-cluster communications socket.
-u32 last_id = 0;		// Last used PPP SID. Can I kill this?? -- mo
+uint32_t 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
@@ -76,11 +76,11 @@ struct cli_tunnel_actions *cli_tunnel_actions = NULL;	// Pending tunnel changes
 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 uint32_t udp_rx = 0, udp_rx_pkt = 0, udp_tx = 0;
+static uint32_t eth_rx = 0, eth_rx_pkt = 0;
+uint32_t eth_tx = 0;
 
-static u32 ip_pool_size = 1;		// Size of the pool of addresses used for dynamic address allocation.
+static uint32_t 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.
@@ -117,6 +117,7 @@ config_descriptt config_values[] = {
 	CONFIG("scheduler_fifo", scheduler_fifo, BOOL),
 	CONFIG("lock_pages", lock_pages, BOOL),
 	CONFIG("icmp_rate", icmp_rate, INT),
+	CONFIG("packet_limit", max_packets, INT),
 	CONFIG("cluster_address", cluster_address, IP),
 	CONFIG("cluster_interface", cluster_interface, STRING),
 	CONFIG("cluster_hb_interval", cluster_hb_interval, INT),
@@ -141,9 +142,13 @@ static char *plugin_functions[] = {
 
 #define max_plugin_functions (sizeof(plugin_functions) / sizeof(char *))
 
+// Counters for shutdown sessions
+static sessiont shut_acct[8192];
+static sessionidt shut_acct_n = 0;
+
 tunnelt *tunnel = NULL;			// Array of tunnel structures.
 sessiont *session = NULL;		// Array of session structures.
-sessioncountt *sess_count = NULL;	// Array of partial per-session traffic counters.
+sessionlocalt *sess_local = NULL;	// Array of local per-session counters.
 radiust *radius = NULL;			// Array of radius structures.
 ippoolt *ip_address_pool = NULL;	// Array of dynamic IP addresses.
 ip_filtert *ip_filters = NULL;	// Array of named filters.
@@ -153,10 +158,10 @@ struct Tstats *_statistics = NULL;
 struct Tringbuffer *ringbuffer = NULL;
 #endif
 
-static void cache_ipmap(ipt ip, int s);
-static void uncache_ipmap(ipt ip);
+static void cache_ipmap(in_addr_t ip, int s);
+static void uncache_ipmap(in_addr_t ip);
 static void free_ip_address(sessionidt s);
-static void dump_acct_info(void);
+static void dump_acct_info(int all);
 static void sighup_handler(int sig);
 static void sigalrm_handler(int sig);
 static void sigterm_handler(int sig);
@@ -164,16 +169,16 @@ 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 build_chap_response(char *challenge, uint8_t id, uint16_t challenge_length, char **challenge_response);
 static void update_config(void);
 static void read_config_file(void);
 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 void processcontrol(uint8_t *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);
+static int unhide_avp(uint8_t *avp, tunnelidt t, sessionidt s, uint16_t length);
 
 // return internal time (10ths since process startup)
 static clockt now(void)
@@ -186,7 +191,7 @@ static 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)
+clockt backoff(uint8_t try)
 {
 	if (try > 5) try = 5;                  // max backoff
 	return now() + 10 * (1 << try);
@@ -241,7 +246,7 @@ void _log(int level, sessionidt s, tunnelidt t, const char *format, ...)
 void _log_hex(int level, const char *title, const char *data, int maxsize)
 {
 	int i, j;
-	const u8 *d = (const u8 *)data;
+	const uint8_t *d = (const uint8_t *) data;
 
 	if (config->debug < level) return;
 
@@ -298,7 +303,7 @@ void _log_hex(int level, const char *title, const char *data, int maxsize)
 //
 // 'ip' and 'mask' must be in _host_ order.
 //
-static void routeset(sessionidt s, ipt ip, ipt mask, ipt gw, u8 add)
+static void routeset(sessionidt s, in_addr_t ip, in_addr_t mask, in_addr_t gw, int add)
 {
 	struct rtentry r;
 	int i;
@@ -310,11 +315,11 @@ static void routeset(sessionidt s, ipt ip, ipt mask, ipt gw, u8 add)
 	memset(&r, 0, sizeof(r));
 	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);
+	*(uint32_t *) & (((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);
+	*(uint32_t *) & (((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);
+	*(uint32_t *) & (((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;
@@ -457,27 +462,26 @@ static void initudp(void)
 // IP address.
 //
 
-static int lookup_ipmap(ipt ip)
+static int lookup_ipmap(in_addr_t ip)
 {
-	u8 *a = (u8 *)&ip;
-	char **d = (char **) ip_hash;
-	int s;
+	uint8_t *a = (uint8_t *) &ip;
+	uint8_t **d = (uint8_t **) ip_hash;
 
-	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;
+	if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
+	if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
+	if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
 
-	s = (ipt) d[(size_t) *a];
-	return s;
+	return (int) (intptr_t) d[(size_t) *a];
 }
 
-sessionidt sessionbyip(ipt ip)
+sessionidt sessionbyip(in_addr_t ip)
 {
 	int s = lookup_ipmap(ip);
 	CSTAT(call_sessionbyip);
 
-	if (s > 0 && s < MAXSESSION && session[s].tunnel)
-		return s;
+	if (s > 0 && s < MAXSESSION && session[s].opened)
+		return (sessionidt) s;
+
 	return 0;
 }
 
@@ -487,25 +491,25 @@ sessionidt sessionbyip(ipt ip)
 //
 // (It's actually cached in network order)
 //
-static void cache_ipmap(ipt ip, int s)
+static void cache_ipmap(in_addr_t ip, int s)
 {
-	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;
+	in_addr_t nip = htonl(ip);	// MUST be in network order. I.e. MSB must in be ((char *) (&ip))[0]
+	uint8_t *a = (uint8_t *) &nip;
+	uint8_t **d = (uint8_t **) ip_hash;
 	int i;
 
 	for (i = 0; i < 3; i++)
 	{
 		if (!d[(size_t) a[i]])
 		{
-			if (!(d[(size_t) a[i]] = calloc(256, sizeof (void *))))
+			if (!(d[(size_t) a[i]] = calloc(256, sizeof(void *))))
 				return;
 		}
 
-		d = (char **) d[(size_t) a[i]];
+		d = (uint8_t **) d[(size_t) a[i]];
 	}
 
-	d[(size_t) a[3]] = (char *)((int)s);
+	d[(size_t) a[3]] = (uint8_t *) (intptr_t) s;
 
 	if (s > 0)
 		LOG(4, s, session[s].tunnel, "Caching ip address %s\n", fmtaddr(nip, 0));
@@ -515,7 +519,7 @@ static void cache_ipmap(ipt ip, int s)
 	// else a map to an ip pool index.
 }
 
-static void uncache_ipmap(ipt ip)
+static void uncache_ipmap(in_addr_t ip)
 {
 	cache_ipmap(ip, 0);	// Assign it to the NULL session.
 }
@@ -538,22 +542,22 @@ int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc)
 	{
 		if (!d[i])
 			continue;
-		e = (char**) d[i];
+		e = (char **) d[i];
 		for (j = 0; j < 256; ++j)
 		{
 			if (!e[j])
 				continue;
-			f = (char**) e[j];
+			f = (char **) e[j];
 			for (k = 0; k < 256; ++k)
 			{
 				if (!f[k])
 					continue;
-				g = (char**)f[k];
+				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);
+					cli_print(cli, "%7d %d.%d.%d.%d", (int) (intptr_t) g[l], i, j, k, l);
 					++count;
 				}
 			}
@@ -575,8 +579,11 @@ sessionidt sessionbyuser(char *username)
 	int s;
 	CSTAT(call_sessionbyuser);
 
-	for (s = 1; s < MAXSESSION ; ++s)
+	for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
 	{
+		if (!session[s].opened)
+			continue;
+
 		if (session[s].walled_garden)
 			continue;		// Skip walled garden users.
 
@@ -587,11 +594,11 @@ sessionidt sessionbyuser(char *username)
 	return 0;	// Not found.
 }
 
-void send_garp(ipt ip)
+void send_garp(in_addr_t ip)
 {
 	int s;
 	struct ifreq ifr;
-	u8 mac[6];
+	uint8_t mac[6];
 
 	s = socket(PF_INET, SOCK_DGRAM, 0);
 	if (s < 0)
@@ -618,22 +625,21 @@ void send_garp(ipt ip)
 	sendarp(ifr.ifr_ifindex, mac, ip);
 }
 
-// Find session by username, 0 for not found
 static sessiont *sessiontbysessionidt(sessionidt s)
 {
-	if (!s || s > MAXSESSION) return NULL;
+	if (!s || s >= MAXSESSION) return NULL;
 	return &session[s];
 }
 
 static sessionidt sessionidtbysessiont(sessiont *s)
 {
 	sessionidt val = s-session;
-	if (s < session || val > MAXSESSION) return 0;
+	if (s < session || val >= MAXSESSION) return 0;
 	return val;
 }
 
 // actually send a control message for a specific tunnel
-void tunnelsend(u8 * buf, u16 l, tunnelidt t)
+void tunnelsend(uint8_t * buf, uint16_t l, tunnelidt t)
 {
 	struct sockaddr_in addr;
 
@@ -659,11 +665,11 @@ void tunnelsend(u8 * buf, u16 l, tunnelidt t)
 
 	memset(&addr, 0, sizeof(addr));
 	addr.sin_family = AF_INET;
-	*(u32 *) & addr.sin_addr = htonl(tunnel[t].ip);
+	*(uint32_t *) & addr.sin_addr = htonl(tunnel[t].ip);
 	addr.sin_port = htons(tunnel[t].port);
 
 	// sequence expected, if sequence in message
-	if (*buf & 0x08) *(u16 *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
+	if (*buf & 0x08) *(uint16_t *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
 
 	// If this is a control message, deal with retries
 	if (*buf & 0x80)
@@ -679,7 +685,7 @@ void tunnelsend(u8 * buf, u16 l, tunnelidt t)
 
 	if (sendto(udpfd, buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
 	{
-		LOG(0, ntohs((*(u16 *) (buf + 6))), t, "Error sending data out tunnel: %s (udpfd=%d, buf=%p, len=%d, dest=%s)\n",
+		LOG(0, ntohs((*(uint16_t *) (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;
@@ -694,37 +700,37 @@ void tunnelsend(u8 * buf, u16 l, tunnelidt t)
 // Tiny helper function to write data to
 // the 'tun' device.
 //
-int tun_write(u8 * data, int size)
+int tun_write(uint8_t * data, int size)
 {
 	return write(tunfd, data, size);
 }
 
 // process outgoing (to tunnel) IP
 //
-static void processipout(u8 * buf, int len)
+static void processipout(uint8_t * buf, int len)
 {
 	sessionidt s;
 	sessiont *sp;
 	tunnelidt t;
-	ipt ip;
+	in_addr_t ip;
 
-	char * data = buf;	// Keep a copy of the originals.
+	char *data = buf;	// Keep a copy of the originals.
 	int size = len;
 
-	u8 b[MAXETHER + 20];
+	uint8_t 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);
+		STAT(tun_rx_errors);
 		return;
 	}
 	if (len >= MAXETHER)
 	{
 		LOG(1, 0, 0, "Oversize IP packet %d bytes\n", len);
-		STAT(tunnel_tx_errors);
+		STAT(tun_rx_errors);
 		return;
 	}
 
@@ -733,13 +739,13 @@ static void processipout(u8 * buf, int len)
 	len -= 4;
 
 	// Got an IP header now
-	if (*(u8 *)(buf) >> 4 != 4)
+	if (*(uint8_t *)(buf) >> 4 != 4)
 	{
 		LOG(1, 0, 0, "IP: Don't understand anything except IPv4\n");
 		return;
 	}
 
-	ip = *(u32 *)(buf + 16);
+	ip = *(uint32_t *)(buf + 16);
 	if (!(s = sessionbyip(ip)))
 	{
 		// Is this a packet for a session that doesn't exist?
@@ -754,14 +760,53 @@ static void processipout(u8 * buf, int len)
 
 		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);
+			LOG(4, 0, 0, "IP: Sending ICMP host unreachable to %s\n", fmtaddr(*(in_addr_t *)(buf + 12), 0));
+			host_unreachable(*(in_addr_t *)(buf + 12), *(uint16_t *)(buf + 4), ip, buf, (len < 64) ? 64 : len);
 		}
 		return;
 	}
 	t = session[s].tunnel;
 	sp = &session[s];
 
+	// DoS prevention: enforce a maximum number of packets per 0.1s for a session
+	if (config->max_packets > 0)
+	{
+		if (sess_local[s].last_packet_out == TIME)
+		{
+			int max = config->max_packets;
+
+			// All packets for throttled sessions are handled by the
+			// master, so further limit by using the throttle rate.
+			// A bit of a kludge, since throttle rate is in kbps,
+			// but should still be generous given our average DSL
+			// packet size is 200 bytes: a limit of 28kbps equates
+			// to around 180 packets per second.
+			if (!config->cluster_iam_master && sp->throttle_out && sp->throttle_out < max)
+				max = sp->throttle_out;
+
+			if (++sess_local[s].packets_out > max)
+			{
+				sess_local[s].packets_dropped++;
+				return;
+			}
+		}
+		else
+		{
+			if (sess_local[s].packets_dropped)
+			{
+				INC_STAT(tun_rx_dropped, sess_local[s].packets_dropped);
+				LOG(3, s, t, "Dropped %u/%u packets to %s for %suser %s\n",
+					sess_local[s].packets_dropped, sess_local[s].packets_out,
+					fmtaddr(ip, 0), sp->throttle_out ? "throttled " : "",
+					sp->user);
+			}
+
+			sess_local[s].last_packet_out = TIME;
+			sess_local[s].packets_out = 1;
+			sess_local[s].packets_dropped = 0;
+		}
+	}
+
 	// run access-list if any
 	if (session[s].filter_out && !ip_filter(buf, len, session[s].filter_out - 1))
 		return;
@@ -786,7 +831,7 @@ static void processipout(u8 * buf, int len)
 
 	// Add on L2TP header
 	{
-		u8 *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
+		uint8_t *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
 		if (!p) return;
 		tunnelsend(b, len + (p-b), t); // send it...
 	}
@@ -799,20 +844,20 @@ static void processipout(u8 * buf, int len)
 	sp->total_cout += len; // byte count
 	sp->pout++;
 	udp_tx += len;
-	sess_count[s].cout += len;	// To send to master..
+	sess_local[s].cout += len;	// To send to master..
 }
 
 //
 // 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)
+static void send_ipout(sessionidt s, uint8_t *buf, int len)
 {
 	sessiont *sp;
 	tunnelidt t;
-	ipt ip;
+	in_addr_t ip;
 
-	u8 b[MAXETHER + 20];
+	uint8_t b[MAXETHER + 20];
 
 	if (len < 0 || len > MAXETHER)
 	{
@@ -824,7 +869,7 @@ static void send_ipout(sessionidt s, u8 *buf, int len)
 	buf += 4;
 	len -= 4;
 
-	ip = *(u32 *)(buf + 16);
+	ip = *(in_addr_t *)(buf + 16);
 
 	if (!session[s].ip)
 		return;
@@ -836,7 +881,7 @@ static void send_ipout(sessionidt s, u8 *buf, int len)
 
 	// Add on L2TP header
 	{
-		u8 *p = makeppp(b, sizeof(b),  buf, len, t, s, PPPIP);
+		uint8_t *p = makeppp(b, sizeof(b),  buf, len, t, s, PPPIP);
 		if (!p) return;
 		tunnelsend(b, len + (p-b), t); // send it...
 	}
@@ -849,55 +894,55 @@ static void send_ipout(sessionidt s, u8 *buf, int len)
 	sp->total_cout += len; // byte count
 	sp->pout++;
 	udp_tx += len;
-	sess_count[s].cout += len;	// To send to master..
+	sess_local[s].cout += len;	// To send to master..
 }
 
 // add an AVP (16 bit)
-static void control16(controlt * c, u16 avp, u16 val, u8 m)
+static void control16(controlt * c, uint16_t avp, uint16_t val, uint8_t m)
 {
-	u16 l = (m ? 0x8008 : 0x0008);
-	*(u16 *) (c->buf + c->length + 0) = htons(l);
-	*(u16 *) (c->buf + c->length + 2) = htons(0);
-	*(u16 *) (c->buf + c->length + 4) = htons(avp);
-	*(u16 *) (c->buf + c->length + 6) = htons(val);
+	uint16_t l = (m ? 0x8008 : 0x0008);
+	*(uint16_t *) (c->buf + c->length + 0) = htons(l);
+	*(uint16_t *) (c->buf + c->length + 2) = htons(0);
+	*(uint16_t *) (c->buf + c->length + 4) = htons(avp);
+	*(uint16_t *) (c->buf + c->length + 6) = htons(val);
 	c->length += 8;
 }
 
 // add an AVP (32 bit)
-static void control32(controlt * c, u16 avp, u32 val, u8 m)
+static void control32(controlt * c, uint16_t avp, uint32_t val, uint8_t m)
 {
-	u16 l = (m ? 0x800A : 0x000A);
-	*(u16 *) (c->buf + c->length + 0) = htons(l);
-	*(u16 *) (c->buf + c->length + 2) = htons(0);
-	*(u16 *) (c->buf + c->length + 4) = htons(avp);
-	*(u32 *) (c->buf + c->length + 6) = htonl(val);
+	uint16_t l = (m ? 0x800A : 0x000A);
+	*(uint16_t *) (c->buf + c->length + 0) = htons(l);
+	*(uint16_t *) (c->buf + c->length + 2) = htons(0);
+	*(uint16_t *) (c->buf + c->length + 4) = htons(avp);
+	*(uint32_t *) (c->buf + c->length + 6) = htonl(val);
 	c->length += 10;
 }
 
 // add an AVP (32 bit)
-static void controls(controlt * c, u16 avp, char *val, u8 m)
+static void controls(controlt * c, uint16_t avp, char *val, uint8_t m)
 {
-	u16 l = ((m ? 0x8000 : 0) + strlen(val) + 6);
-	*(u16 *) (c->buf + c->length + 0) = htons(l);
-	*(u16 *) (c->buf + c->length + 2) = htons(0);
-	*(u16 *) (c->buf + c->length + 4) = htons(avp);
+	uint16_t l = ((m ? 0x8000 : 0) + strlen(val) + 6);
+	*(uint16_t *) (c->buf + c->length + 0) = htons(l);
+	*(uint16_t *) (c->buf + c->length + 2) = htons(0);
+	*(uint16_t *) (c->buf + c->length + 4) = htons(avp);
 	memcpy(c->buf + c->length + 6, val, strlen(val));
 	c->length += 6 + strlen(val);
 }
 
 // add a binary AVP
-static void controlb(controlt * c, u16 avp, char *val, unsigned int len, u8 m)
+static void controlb(controlt * c, uint16_t avp, char *val, unsigned int len, uint8_t m)
 {
-	u16 l = ((m ? 0x8000 : 0) + len + 6);
-	*(u16 *) (c->buf + c->length + 0) = htons(l);
-	*(u16 *) (c->buf + c->length + 2) = htons(0);
-	*(u16 *) (c->buf + c->length + 4) = htons(avp);
+	uint16_t l = ((m ? 0x8000 : 0) + len + 6);
+	*(uint16_t *) (c->buf + c->length + 0) = htons(l);
+	*(uint16_t *) (c->buf + c->length + 2) = htons(0);
+	*(uint16_t *) (c->buf + c->length + 4) = htons(avp);
 	memcpy(c->buf + c->length + 6, val, len);
 	c->length += 6 + len;
 }
 
 // new control connection
-static controlt *controlnew(u16 mtype)
+static controlt *controlnew(uint16_t mtype)
 {
 	controlt *c;
 	if (!controlfree)
@@ -909,7 +954,7 @@ static controlt *controlnew(u16 mtype)
 	}
 	assert(c);
 	c->next = 0;
-	*(u16 *) (c->buf + 0) = htons(0xC802); // flags/ver
+	*(uint16_t *) (c->buf + 0) = htons(0xC802); // flags/ver
 	c->length = 12;
 	control16(c, 0, mtype, 1);
 	return c;
@@ -919,26 +964,26 @@ static controlt *controlnew(u16 mtype)
 // (ZLB send).
 static void controlnull(tunnelidt t)
 {
-	u8 buf[12];
+	uint8_t buf[12];
 	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
-	*(u16 *) (buf + 6) = htons(0); // session
-	*(u16 *) (buf + 8) = htons(tunnel[t].ns); // sequence
-	*(u16 *) (buf + 10) = htons(tunnel[t].nr); // sequence
+	*(uint16_t *) (buf + 0) = htons(0xC802); // flags/ver
+	*(uint16_t *) (buf + 2) = htons(12); // length
+	*(uint16_t *) (buf + 4) = htons(tunnel[t].far); // tunnel
+	*(uint16_t *) (buf + 6) = htons(0); // session
+	*(uint16_t *) (buf + 8) = htons(tunnel[t].ns); // sequence
+	*(uint16_t *) (buf + 10) = htons(tunnel[t].nr); // sequence
 	tunnelsend(buf, 12, t);
 }
 
 // add a control message to a tunnel, and send if within window
 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
-	*(u16 *) (c->buf + 6) = htons(s ? session[s].far : 0); // session
-	*(u16 *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
+	*(uint16_t *) (c->buf + 2) = htons(c->length); // length
+	*(uint16_t *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
+	*(uint16_t *) (c->buf + 6) = htons(s ? session[s].far : 0); // session
+	*(uint16_t *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
 	tunnel[t].ns++;              // advance sequence
 	// link in message in to queue
 	if (tunnel[t].controlc)
@@ -969,7 +1014,7 @@ static void controladd(controlt * c, tunnelidt t, sessionidt s)
 //
 void throttle_session(sessionidt s, int rate_in, int rate_out)
 {
-	if (!session[s].tunnel)
+	if (!session[s].opened)
 		return; // No-one home.
 
 	if (!*session[s].user)
@@ -1007,7 +1052,7 @@ void throttle_session(sessionidt s, int rate_in, int rate_out)
 // add/remove filters from session (-1 = no change)
 void filter_session(sessionidt s, int filter_in, int filter_out)
 {
-	if (!session[s].tunnel)
+	if (!session[s].opened)
 		return; // No-one home.
 
 	if (!*session[s].user)
@@ -1050,9 +1095,9 @@ void sessionshutdown(sessionidt s, char *reason)
 
 	CSTAT(call_sessionshutdown);
 
-	if (!session[s].tunnel)
+	if (!session[s].opened)
 	{
-		LOG(3, s, session[s].tunnel, "Called sessionshutdown on a session with no tunnel.\n");
+		LOG(3, s, session[s].tunnel, "Called sessionshutdown on an unopened session.\n");
 		return;                   // not a live session
 	}
 
@@ -1063,10 +1108,10 @@ void sessionshutdown(sessionidt s, char *reason)
 		run_plugins(PLUGIN_KILL_SESSION, &data);
 	}
 
-	// RADIUS Stop message
 	if (session[s].opened && !walled_garden && !session[s].die)
 	{
-		u16 r = session[s].radius;
+		// RADIUS Stop message
+		uint16_t r = session[s].radius;
 		if (!r)
 		{
 			if (!(r = radiusnew(s)))
@@ -1081,8 +1126,13 @@ void sessionshutdown(sessionidt s, char *reason)
 					radius[r].auth[n] = rand();
 			}
 		}
+
 		if (r && radius[r].state != RADIUSSTOP)
 			radiussend(r, RADIUSSTOP); // stop, if not already trying
+
+	    	// Save counters to dump to accounting file
+		if (*config->accounting_dir && shut_acct_n < sizeof(shut_acct) / sizeof(*shut_acct))
+			memcpy(&shut_acct[shut_acct_n++], &session[s], sizeof(session[s]));
 	}
 
 	if (session[s].ip)
@@ -1119,7 +1169,7 @@ void sessionshutdown(sessionidt s, char *reason)
 	}
 
 	if (!session[s].die)
-		session[s].die = now() + 150; // Clean up in 15 seconds
+		session[s].die = TIME + 150; // Clean up in 15 seconds
 
 	// update filter refcounts
 	if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
@@ -1130,9 +1180,9 @@ void sessionshutdown(sessionidt s, char *reason)
 
 void sendipcp(tunnelidt t, sessionidt s)
 {
-	u8 buf[MAXCONTROL];
-	u16 r = session[s].radius;
-	u8 *q;
+	uint8_t buf[MAXCONTROL];
+	uint16_t r = session[s].radius;
+	uint8_t *q;
 
 	CSTAT(call_sendipcp);
 
@@ -1158,24 +1208,33 @@ void sendipcp(tunnelidt t, sessionidt s)
 
 	*q = ConfigReq;
 	q[1] = r << RADIUS_SHIFT;                    // ID, dont care, we only send one type of request
-	*(u16 *) (q + 2) = htons(10);
+	*(uint16_t *) (q + 2) = htons(10);
 	q[4] = 3;
 	q[5] = 6;
-	*(u32 *) (q + 6) = config->peer_address ? config->peer_address :
-	    		   config->bind_address ? config->bind_address :
-			   my_address; // send my IP
+	*(in_addr_t *) (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
-static void sessionkill(sessionidt s, char *reason)
+void sessionkill(sessionidt s, char *reason)
 {
 
 	CSTAT(call_sessionkill);
 
-	session[s].die = now();
+	if (!session[s].opened) // not alive
+		return;
+
+	if (session[s].next)
+	{
+		LOG(0, s, session[s].tunnel, "Tried to kill a session with next pointer set (%d)\n", session[s].next);
+		return;
+	}
+
+	session[s].die = TIME;
 	sessionshutdown(s, reason);  // close radius/routes, etc.
 	if (session[s].radius)
 		radiusclear(session[s].radius, s); // cant send clean accounting data, session is killed
@@ -1217,7 +1276,7 @@ static void tunnelkill(tunnelidt t, char *reason)
 		controlfree = c;
 	}
 	// kill sessions
-	for (s = 1; s < MAXSESSION; s++)
+	for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
 		if (session[s].tunnel == t)
 			sessionkill(s, reason);
 
@@ -1244,28 +1303,28 @@ static void tunnelshutdown(tunnelidt t, char *reason)
 	LOG(1, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
 
 	// close session
-	for (s = 1; s < MAXSESSION; s++)
+	for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
 		if (session[s].tunnel == t)
 			sessionshutdown(s, reason);
 
 	tunnel[t].state = TUNNELDIE;
-	tunnel[t].die = now() + 700; // Clean up in 70 seconds
+	tunnel[t].die = TIME + 700; // Clean up in 70 seconds
 	cluster_send_tunnel(t);
 	// TBA - should we wait for sessions to stop?
 	{                            // Send StopCCN
 		controlt *c = controlnew(4); // sending StopCCN
-		control16(c, 1, 1, 1);    // result code (admin reasons - TBA make error, general error, add message
+		control16(c, 1, 1, 1);    // result code (admin reasons - TBA make error, general error, add message)
 		control16(c, 9, t, 1);    // assigned tunnel (our end)
 		controladd(c, t, 0);      // send the message
 	}
 }
 
 // read and process packet on tunnel (UDP)
-void processudp(u8 * buf, int len, struct sockaddr_in *addr)
+void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
 {
 	char *chapresponse = NULL;
-	u16 l = len, t = 0, s = 0, ns = 0, nr = 0;
-	u8 *p = buf + 2;
+	uint16_t l = len, t = 0, s = 0, ns = 0, nr = 0;
+	uint8_t *p = buf + 2;
 
 
 	CSTAT(call_processudp);
@@ -1289,12 +1348,12 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 	}
 	if (*buf & 0x40)
 	{                          // length
-		l = ntohs(*(u16 *) p);
+		l = ntohs(*(uint16_t *) p);
 		p += 2;
 	}
-	t = ntohs(*(u16 *) p);
+	t = ntohs(*(uint16_t *) p);
 	p += 2;
-	s = ntohs(*(u16 *) p);
+	s = ntohs(*(uint16_t *) p);
 	p += 2;
 	if (s >= MAXSESSION)
 	{
@@ -1310,36 +1369,36 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 	}
 	if (*buf & 0x08)
 	{                          // ns/nr
-		ns = ntohs(*(u16 *) p);
+		ns = ntohs(*(uint16_t *) p);
 		p += 2;
-		nr = ntohs(*(u16 *) p);
+		nr = ntohs(*(uint16_t *) p);
 		p += 2;
 	}
 	if (*buf & 0x02)
 	{                          // offset
-		u16 o = ntohs(*(u16 *) p);
+		uint16_t o = ntohs(*(uint16_t *) p);
 		p += o + 2;
 	}
 	if ((p - buf) > l)
 	{
-		LOG(1, s, t, "Bad length %d>%d\n", (p - buf), l);
+		LOG(1, s, t, "Bad length %d>%d\n", (int) (p - buf), l);
 		STAT(tunnel_rx_errors);
 		return;
 	}
 	l -= (p - buf);
 	if (*buf & 0x80)
 	{                          // control
-		u16 message = 0xFFFF; // message type
-		u8 fatal = 0;
-		u8 mandatorymessage = 0;
-		u8 chap = 0;      // if CHAP being used
-		u16 asession = 0;  // assigned session
-		u32 amagic = 0;    // magic number
-		u8 aflags = 0;    // flags from last LCF
-		u16 version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
-		int requestchap = 0;	// do we request PAP instead of original CHAP request?
-		char called[MAXTEL] = ""; // called number
-		char calling[MAXTEL] = ""; // calling number
+		uint16_t message = 0xFFFF;	// message type
+		uint8_t fatal = 0;
+		uint8_t mandatorymessage = 0;
+		uint8_t chap = 0;		// if CHAP being used
+		uint16_t asession = 0;		// assigned session
+		uint32_t amagic = 0;		// magic number
+		uint8_t aflags = 0;		// flags from last LCF
+		uint16_t version = 0x0100;	// protocol version (we handle 0.0 as well and send that back just in case)
+		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)
 		{
@@ -1365,7 +1424,7 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 			for (i = 1; i <= config->cluster_highest_tunnelid ; ++i)
 			{
 				if (tunnel[i].state != TUNNELOPENING ||
-					tunnel[i].ip != ntohl(*(ipt *) & addr->sin_addr) ||
+					tunnel[i].ip != ntohl(*(in_addr_t *) & addr->sin_addr) ||
 					tunnel[i].port != ntohs(addr->sin_port) )
 					continue;
 				t = i;
@@ -1387,7 +1446,7 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 				return;
 			}
 			tunnelclear(t);
-			tunnel[t].ip = ntohl(*(ipt *) & addr->sin_addr);
+			tunnel[t].ip = ntohl(*(in_addr_t *) & addr->sin_addr);
 			tunnel[t].port = ntohs(addr->sin_port);
 			tunnel[t].window = 4; // default window
 			STAT(tunnel_created);
@@ -1460,10 +1519,10 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 			// process AVPs
 			while (l && !(fatal & 0x80))
 			{
-				u16 n = (ntohs(*(u16 *) p) & 0x3FF);
-				u8 *b = p;
-				u8 flags = *p;
-				u16 mtype;
+				uint16_t n = (ntohs(*(uint16_t *) p) & 0x3FF);
+				uint8_t *b = p;
+				uint8_t flags = *p;
+				uint16_t mtype;
 				p += n;       // next
 				if (l < n)
 				{
@@ -1504,14 +1563,14 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 					continue; // next
 				}
 				b += 2;
-				if (*(u16 *) (b))
+				if (*(uint16_t *) (b))
 				{
-					LOG(2, s, t, "Unknown AVP vendor %d\n", ntohs(*(u16 *) (b)));
+					LOG(2, s, t, "Unknown AVP vendor %d\n", ntohs(*(uint16_t *) (b)));
 					fatal = flags;
 					continue; // next
 				}
 				b += 2;
-				mtype = ntohs(*(u16 *) (b));
+				mtype = ntohs(*(uint16_t *) (b));
 				b += 2;
 				n -= 6;
 
@@ -1519,13 +1578,13 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 				switch (mtype)
 				{
 				case 0:     // message type
-					message = ntohs(*(u16 *) b);
+					message = ntohs(*(uint16_t *) b);
 					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));
+						uint16_t rescode = ntohs(*(uint16_t *) b);
 						const char* resdesc = "(unknown)";
 						if (message == 4)
 						{ /* StopCCN */
@@ -1541,7 +1600,7 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 						LOG(4, s, t, "   Result Code %d: %s\n", rescode, resdesc);
 						if (n >= 4)
 						{
-							u16 errcode = ntohs(*(u16 *)(b + 2));
+							uint16_t errcode = ntohs(*(uint16_t *)(b + 2));
 							const char* errdesc = "(unknown)";
 							if (errcode <= MAX_ERROR_CODE)
 								errdesc = error_codes[errcode];
@@ -1555,7 +1614,7 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 					break;
 				case 2:     // protocol version
 					{
-						version = ntohs(*(u16 *) (b));
+						version = ntohs(*(uint16_t *) (b));
 						LOG(4, s, t, "   Protocol version = %d\n", version);
 						if (version && version != 0x0100)
 						{   // allow 0.0 and 1.0
@@ -1590,11 +1649,11 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 					LOG(4, s, t, "   Vendor name = \"%s\"\n", tunnel[t].vendor);
 					break;
 				case 9:     // assigned tunnel
-					tunnel[t].far = ntohs(*(u16 *) (b));
+					tunnel[t].far = ntohs(*(uint16_t *) (b));
 					LOG(4, s, t, "   Remote tunnel id = %d\n", tunnel[t].far);
 					break;
 				case 10:    // rx window
-					tunnel[t].window = ntohs(*(u16 *) (b));
+					tunnel[t].window = ntohs(*(uint16_t *) (b));
 					if (!tunnel[t].window)
 						tunnel[t].window = 1; // window of 0 is silly
 					LOG(4, s, t, "   rx window = %d\n", tunnel[t].window);
@@ -1611,18 +1670,18 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 					break;
 
 				case 14:    // assigned session
-					asession = session[s].far = ntohs(*(u16 *) (b));
+					asession = session[s].far = ntohs(*(uint16_t *) (b));
 					LOG(4, s, t, "   assigned session = %d\n", asession);
 					break;
 				case 15:    // call serial number
-					LOG(4, s, t, "   call serial number = %d\n", ntohl(*(u32 *)b));
+					LOG(4, s, t, "   call serial number = %d\n", ntohl(*(uint32_t *)b));
 					break;
 				case 18:    // bearer type
-					LOG(4, s, t, "   bearer type = %d\n", ntohl(*(u32 *)b));
+					LOG(4, s, t, "   bearer type = %d\n", ntohl(*(uint32_t *)b));
 					// TBA - for RADIUS
 					break;
 				case 19:    // framing type
-					LOG(4, s, t, "   framing type = %d\n", ntohl(*(u32 *)b));
+					LOG(4, s, t, "   framing type = %d\n", ntohl(*(uint32_t *)b));
 					// TBA
 					break;
 				case 21:    // called number
@@ -1640,7 +1699,7 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 				case 24:    // tx connect speed
 					if (n == 4)
 					{
-						session[s].tx_connect_speed = ntohl(*(u32 *)b);
+						session[s].tx_connect_speed = ntohl(*(uint32_t *)b);
 					}
 					else
 					{
@@ -1654,7 +1713,7 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 				case 38:    // rx connect speed
 					if (n == 4)
 					{
-						session[s].rx_connect_speed = ntohl(*(u32 *)b);
+						session[s].rx_connect_speed = ntohl(*(uint32_t *)b);
 					}
 					else
 					{
@@ -1667,13 +1726,13 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 					break;
 				case 25:    // Physical Channel ID
 					{
-						u32 tmp = ntohl(*(u32 *)b);
+						uint32_t tmp = ntohl(*(uint32_t *) b);
 						LOG(4, s, t, "   Physical Channel ID <%X>\n", tmp);
 						break;
 					}
 				case 29:    // Proxy Authentication Type
 					{
-						u16 authtype = ntohs(*(u16 *)b);
+						uint16_t authtype = ntohs(*(uint16_t *)b);
 						LOG(4, s, t, "   Proxy Auth Type %d (%s)\n", authtype, authtypes[authtype]);
 						requestchap = (authtype == 2);
 						break;
@@ -1694,7 +1753,7 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 					}
 				case 32:    // Proxy Authentication ID
 					{
-						u16 authid = ntohs(*(u16 *)(b));
+						uint16_t authid = ntohs(*(uint16_t *)(b));
 						LOG(4, s, t, "   Proxy Auth ID (%d)\n", authid);
 						if (session[s].radius)
 							radius[session[s].radius].id = authid;
@@ -1709,12 +1768,12 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 					}
 				case 27:    // last send lcp
 					{        // find magic number
-						u8 *p = b, *e = p + n;
+						uint8_t *p = b, *e = p + n;
 						while (p + 1 < e && p[1] && p + p[1] <= e)
 						{
 							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) // Authentication-Protocol
+								amagic = ntohl(*(uint32_t *) (p + 2));
+							else if (*p == 3 && p[1] == 5 && *(uint16_t *) (p + 2) == htons(PPPCHAP) && p[4] == 5) // Authentication-Protocol
 								chap = 1;
 							else if (*p == 7) // Protocol-Field-Compression
 								aflags |= SESSIONPFC;
@@ -1731,7 +1790,7 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 				case 39:    // seq required - we control it as an LNS anyway...
 					break;
 				case 36:    // Random Vector
-					LOG(4, 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;
@@ -1788,11 +1847,12 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 					if (!sessionfree)
 					{
 						STAT(session_overflow);
-						tunnelshutdown(t, "No free sessions");
+						LOG(1, 0, t, "No free sessions");
+						return;
 					}
 					else
 					{
-						u16 r;
+						uint16_t r;
 						controlt *c;
 
 						s = sessionfree;
@@ -1812,7 +1872,7 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 
 						c = controlnew(11); // sending ICRP
 						session[s].id = sessionid++;
-						session[s].opened = time(NULL);
+						session[s].opened = time_now;
 						session[s].tunnel = t;
 						session[s].far = asession;
 						session[s].last_packet = time_now;
@@ -1869,7 +1929,7 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 	}
 	else
 	{                          // data
-		u16 prot;
+		uint16_t prot;
 
 		LOG_HEX(5, "Receive Tunnel Data", p, l);
 		if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
@@ -1890,12 +1950,12 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 		}
 		else
 		{
-			prot = ntohs(*(u16 *) p);
+			prot = ntohs(*(uint16_t *) p);
 			p += 2;
 			l -= 2;
 		}
 
-		if (s && !session[s].tunnel)	// Is something wrong??
+		if (s && !session[s].opened)	// Is something wrong??
 		{
 			if (!config->cluster_iam_master)
 			{
@@ -1904,20 +1964,11 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 				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);
-
+			LOG(1, s, t, "UDP packet contains session which is not opened.  Dropping packet.\n");
 			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;
@@ -1950,12 +2001,19 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 		}
 		else if (prot == PPPIP)
 		{
+			if (session[s].die)
+			{
+				LOG(4, s, t, "Session %d is closing.  Don't process PPP packets\n", s);
+				return;              // closing session, PPP not processed
+			}
+
 			session[s].last_packet = time_now;
 			if (session[s].walled_garden && !config->cluster_iam_master)
 			{
 				master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
 				return;
 			}
+
 			processipin(t, s, p, l);
 		}
 		else
@@ -1967,7 +2025,7 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 }
 
 // read and process packet on tun
-static void processtun(u8 * buf, int len)
+static void processtun(uint8_t * buf, int len)
 {
 	LOG_HEX(5, "Receive TUN Data", buf, len);
 	STAT(tun_rx_packets);
@@ -1984,7 +2042,7 @@ static void processtun(u8 * buf, int len)
 		return;
 	}
 
-	if (*(u16 *) (buf + 2) == htons(PKTIP)) // IP
+	if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IP
 		processipout(buf, len);
 	// Else discard.
 }
@@ -2000,8 +2058,9 @@ static int regular_cleanups(void)
 	static sessionidt s = 0;	// Next session to check for actions on.
 	tunnelidt t;
 	int count=0,i;
-	u16 r;
+	uint16_t r;
 	static clockt next_acct = 0;
+	static clockt next_shut_acct = 0;
 	int a;
 
 	LOG(3, 0, 0, "Begin regular cleanup\n");
@@ -2033,7 +2092,7 @@ static int regular_cleanups(void)
 			if (tunnel[t].retry <= TIME)
 			{
 				controlt *c = tunnel[t].controls;
-				u8 w = tunnel[t].window;
+				uint8_t w = tunnel[t].window;
 				tunnel[t].try++; // another try
 				if (tunnel[t].try > 5)
 					tunnelkill(t, "Timeout on control message"); // game over
@@ -2073,7 +2132,7 @@ static int regular_cleanups(void)
 		if (s > config->cluster_highest_sessionid)
 			s = 1;
 
-		if (!session[s].tunnel)	// Session isn't in use
+		if (!session[s].opened)	// Session isn't in use
 			continue;
 
 		if (!session[s].die && session[s].ip && !(session[s].flags & SF_IPCP_ACKED))
@@ -2094,7 +2153,7 @@ static int regular_cleanups(void)
 		// Drop sessions who have not responded within IDLE_TIMEOUT seconds
 		if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
 		{
-			sessionkill(s, "No response to LCP ECHO requests");
+			sessionshutdown(s, "No response to LCP ECHO requests");
 			STAT(session_timeout);
 			if (++count >= MAX_ACTIONS) break;
 			continue;
@@ -2103,15 +2162,15 @@ static int regular_cleanups(void)
 		// 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};
+			uint8_t b[MAXCONTROL] = {0};
 
-			u8 *q = makeppp(b, sizeof(b), 0, 0, session[s].tunnel, s, PPPLCP);
+			uint8_t *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)
+			*(uint8_t *)(q + 1) = (time_now % 255); // ID
+			*(uint16_t *)(q + 2) = htons(8); // Length
+			*(uint32_t *)(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));
@@ -2189,11 +2248,22 @@ static int regular_cleanups(void)
 		}
 	}
 
-	if (*config->accounting_dir && next_acct <= TIME)
+	if (*config->accounting_dir)
 	{
-		// Dump accounting data
-		next_acct = TIME + ACCT_TIME;
-		dump_acct_info();
+		if (next_acct <= TIME)
+		{
+			// Dump accounting data
+			next_acct = TIME + ACCT_TIME;
+			next_shut_acct = TIME + ACCT_SHUT_TIME;
+			dump_acct_info(1);
+		}
+		else if (next_shut_acct <= TIME)
+		{
+			// Dump accounting data for shutdown sessions
+			next_shut_acct = TIME + ACCT_SHUT_TIME;
+			if (shut_acct_n)
+				dump_acct_info(0);
+		}
 	}
 
 	if (count >= MAX_ACTIONS)
@@ -2232,7 +2302,7 @@ static int still_busy(void)
 	// We stop waiting for radius after BUSY_WAIT_TIME 1/10th seconds
 	if (abs(TIME - start_busy_wait) > BUSY_WAIT_TIME)
 	{
-		LOG(1, 0, 0, "Giving up waiting for RADIUS to be empty. Shutting down anyway.\n");
+		LOG(1, 0, 0, "Giving up waiting for RADIUS to be empty.  Shutting down anyway.\n");
 		return 0;
 	}
 
@@ -2261,12 +2331,12 @@ static int readset_n = 0;
 static void mainloop(void)
 {
 	int i;
-	u8 buf[65536];
+	uint8_t 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",
+	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);
@@ -2325,6 +2395,8 @@ static void mainloop(void)
 		n = select(n + 1, &r, 0, 0, &to);
 #endif /* BGP */
 
+		STAT(select_called);
+
 		TIME = now();
 		if (n < 0)
 		{
@@ -2339,62 +2411,120 @@ static void mainloop(void)
 		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 alen, c, s;
+			int udp_pkts = 0;
+			int tun_pkts = 0;
+			int cluster_pkts = 0;
+
+			// nsctl commands
+			if (FD_ISSET(controlfd, &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;
-				}
+				alen = sizeof(addr);
+				processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
+				n--;
 			}
 
+			// RADIUS responses
 			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);
+						n--;
+					}
+				}
+			}
 
-			if (FD_ISSET(cluster_sockfd, &r))
+			// CLI connections
+			if (FD_ISSET(clifd, &r))
 			{
-				int size;
-				size = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen);
-				processcluster(buf, size, addr.sin_addr.s_addr);
+				int cli;
+				
+				alen = sizeof(addr);
+				if ((cli = accept(clifd, (struct sockaddr *)&addr, &alen)) >= 0)
+				{
+					cli_do(cli);
+					close(cli);
+				}
+				else
+					LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
+
+				n--;
 			}
 
-			if (FD_ISSET(controlfd, &r))
-				processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
+#ifdef BGP
+			for (i = 0; i < BGP_NUM_PEERS; i++)
+			{
+				int isr = bgp_set[i] ? FD_ISSET(bgp_peers[i].sock, &r) : 0;
+				int isw = bgp_set[i] ? FD_ISSET(bgp_peers[i].sock, &w) : 0;
+				bgp_process(&bgp_peers[i], isr, isw);
+				if (isr) n--;
+				if (isw) n--;
+			}
+#endif /* BGP */
 
-			if (FD_ISSET(clifd, &r))
+			for (c = 0; n && c < config->multi_read_count; c++)
 			{
-				struct sockaddr_in addr;
-				int sockfd;
-				int len = sizeof(addr);
+				// L2TP
+				if (FD_ISSET(udpfd, &r))
+				{
+					alen = sizeof(addr);
+					if ((s = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
+					{
+						processudp(buf, s, &addr);
+						udp_pkts++;
+					}
+					else
+					{
+						FD_CLR(udpfd, &r);
+						n--;
+					}
+				}
 
-				if ((sockfd = accept(clifd, (struct sockaddr *)&addr, &len)) <= 0)
+				// incoming IP
+				if (FD_ISSET(tunfd, &r))
 				{
-					LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
-					continue;
+					if ((s = read(tunfd, buf, sizeof(buf))) > 0)
+					{
+						processtun(buf, s);
+					    	tun_pkts++;
+					}
+					else
+					{
+						FD_CLR(tunfd, &r);
+						n--;
+					}
 				}
-				else
+
+				// cluster
+				if (FD_ISSET(cluster_sockfd, &r))
 				{
-					cli_do(sockfd);
-					close(sockfd);
+					alen = sizeof(addr);
+					if ((s = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen)) > 0)
+					{
+						processcluster(buf, s, addr.sin_addr.s_addr);
+						cluster_pkts++;
+					}
+					else
+					{
+						FD_CLR(cluster_sockfd, &r);
+						n--;
+					}
 				}
 			}
+
+			if (udp_pkts > 1 || tun_pkts > 1 || cluster_pkts > 1)
+				STAT(multi_read_used);
+
+			if (c >= config->multi_read_count)
+			{
+				LOG(3, 0, 0, "Reached multi_read_count (%d); processed %d udp, %d tun and %d cluster packets\n",
+					config->multi_read_count, udp_pkts, tun_pkts, cluster_pkts);
+
+				STAT(multi_read_exceeded);
+			}
 		}
 
 			// Runs on every machine (master and slaves).
@@ -2444,15 +2574,6 @@ static void mainloop(void)
 				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??
@@ -2565,9 +2686,9 @@ static void initdata(int optdebug, char *optconfig)
 		exit(1);
 	}
 
-	if (!(sess_count = shared_malloc(sizeof(sessioncountt) * MAXSESSION)))
+	if (!(sess_local = shared_malloc(sizeof(sessionlocalt) * MAXSESSION)))
 	{
-		LOG(0, 0, 0, "Error doing malloc for sessions_count: %s\n", strerror(errno));
+		LOG(0, 0, 0, "Error doing malloc for sess_local: %s\n", strerror(errno));
 		exit(1);
 	}
 
@@ -2619,7 +2740,7 @@ memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
 	memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
 
 		// Put all the sessions on the free list marked as undefined.
-	for (i = 1; i < MAXSESSION - 1; i++)
+	for (i = 1; i < MAXSESSION; i++)
 	{
 		session[i].next = i + 1;
 		session[i].tunnel = T_UNDEF;	// mark it as not filled in.
@@ -2628,7 +2749,7 @@ memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
 	sessionfree = 1;
 
 		// Mark all the tunnels as undefined (waiting to be filled in by a download).
-	for (i = 1; i < MAXTUNNEL- 1; i++)
+	for (i = 1; i < MAXTUNNEL; i++)
 		tunnel[i].state = TUNNELUNDEF;	// mark it as not filled in.
 
 	if (!*hostname)
@@ -2651,7 +2772,7 @@ memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
 
 static int assign_ip_address(sessionidt s)
 {
-	u32 i;
+	uint32_t i;
 	int best = -1;
 	time_t best_time = time_now;
 	char *u = session[s].user;
@@ -2754,7 +2875,7 @@ void rebuild_address_pool(void)
 	for (i = 0; i < MAXSESSION; ++i)
 	{
 		int ipid;
-		if (!session[i].ip || !session[i].tunnel)
+		if (!(session[i].opened && session[i].ip))
 			continue;
 		ipid = - lookup_ipmap(htonl(session[i].ip));
 
@@ -2812,7 +2933,7 @@ static void fix_address_pool(int sid)
 //
 // Add a block of addresses to the IP pool to hand out.
 //
-static void add_to_ip_pool(u32 addr, u32 mask)
+static void add_to_ip_pool(in_addr_t addr, in_addr_t mask)
 {
 	int i;
 	if (mask == 0)
@@ -2863,7 +2984,7 @@ static void initippool()
 		if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
 		if ((p = (char *)strchr(buf, ':')))
 		{
-			ipt src;
+			in_addr_t src;
 			*p = '\0';
 			src = inet_addr(buf);
 			if (src == INADDR_NONE)
@@ -2881,7 +3002,7 @@ static void initippool()
 		{
 			// It's a range
 			int numbits = 0;
-			u32 start = 0, mask = 0;
+			in_addr_t start = 0, mask = 0;
 
 			LOG(2, 0, 0, "Adding IP address range %s\n", buf);
 			*p++ = 0;
@@ -2891,7 +3012,7 @@ static void initippool()
 				continue;
 			}
 			start = ntohl(inet_addr(pool));
-			mask = (u32)(pow(2, numbits) - 1) << (32 - numbits);
+			mask = (in_addr_t) (pow(2, numbits) - 1) << (32 - numbits);
 
 			// Add a static route for this pool
 			LOG(5, 0, 0, "Adding route for address pool %s/%u\n",
@@ -2911,7 +3032,7 @@ static void initippool()
 	LOG(1, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
 }
 
-void snoop_send_packet(char *packet, u16 size, ipt destination, u16 port)
+void snoop_send_packet(char *packet, uint16_t size, in_addr_t destination, uint16_t port)
 {
 	struct sockaddr_in snoop_addr = {0};
 	if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
@@ -2921,8 +3042,8 @@ void snoop_send_packet(char *packet, u16 size, ipt destination, u16 port)
 	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),
+	LOG(5, 0, 0, "Snooping %d byte packet to %s:%d\n", 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)
@@ -2931,55 +3052,71 @@ void snoop_send_packet(char *packet, u16 size, ipt destination, u16 port)
 	STAT(packets_snooped);
 }
 
-static void dump_acct_info()
+static int dump_session(FILE **f, sessiont *s)
+{
+	if (!s->opened || !s->ip || !(s->cin || s->cout) || !*s->user || s->walled_garden)
+		return 1;
+
+	if (!*f)
+	{
+		char filename[1024];
+		char timestr[64];
+		time_t now = time(NULL);
+
+		strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(&now));
+		snprintf(filename, sizeof(filename), "%s/%s", config->accounting_dir, timestr);
+
+		if (!(*f = fopen(filename, "w")))
+		{
+			LOG(0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
+			return 0;
+		}
+
+		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", s->user);
+	fprintf(*f, "%s %s %d %u %u\n",
+		s->user,						// username
+		fmtaddr(htonl(s->ip), 0),				// ip
+		(s->throttle_in || s->throttle_out) ? 2 : 1,		// qos
+		(uint32_t) s->cin,					// uptxoctets
+		(uint32_t) s->cout);					// downrxoctets
+
+	s->pin = s->cin = 0;
+	s->pout = s->cout = 0;
+
+	return 1;
+}
+
+static void dump_acct_info(int all)
 {
-	char filename[1024];
-	char timestr[64];
-	time_t t = time(NULL);
 	int i;
 	FILE *f = NULL;
 
 
 	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 (shut_acct_n)
 	{
-		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);
-		}
+		for (i = 0; i < shut_acct_n; i++)
+			dump_session(&f, &shut_acct[i]);
 
-		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;
+		shut_acct_n = 0;
 	}
 
+	if (all)
+		for (i = 1; i <= config->cluster_highest_sessionid; i++)
+			dump_session(&f, &session[i]);
+
 	if (f)
 		fclose(f);
 }
@@ -3040,7 +3177,7 @@ int main(int argc, char *argv[])
 	init_tbf(config->num_tbfs);
 
 	LOG(0, 0, 0, "L2TPNS version " VERSION "\n");
-	LOG(0, 0, 0, "Copyright (c) 2003, 2004 Optus Internet Engineering\n");
+	LOG(0, 0, 0, "Copyright (c) 2003, 2004, 2005 Optus Internet Engineering\n");
 	LOG(0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
 	{
 		struct rlimit rlim;
@@ -3069,7 +3206,7 @@ int main(int argc, char *argv[])
 		{
 			if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
 			{
-				LOG(1, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
+				LOG(1, 0, 0, "Using FIFO scheduler.  Say goodbye to any other processes running\n");
 			}
 			else
 			{
@@ -3207,15 +3344,19 @@ static void sigquit_handler(int sig)
 	int i;
 
 	LOG(1, 0, 0, "Shutting down without saving sessions\n");
-	for (i = 1; i < MAXSESSION; i++)
-	{
-		if (session[i].opened)
-			sessionkill(i, "L2TPNS Closing");
-	}
-	for (i = 1; i < MAXTUNNEL; i++)
+
+	if (config->cluster_iam_master)
 	{
-		if (tunnel[i].ip || tunnel[i].state)
-			tunnelshutdown(i, "L2TPNS Closing");
+		for (i = 1; i < MAXSESSION; i++)
+		{
+			if (session[i].opened)
+				sessionkill(i, "L2TPNS Closing");
+		}
+		for (i = 1; i < MAXTUNNEL; i++)
+		{
+			if (tunnel[i].ip || tunnel[i].state)
+				tunnelshutdown(i, "L2TPNS Closing");
+		}
 	}
 
 	main_quit++;
@@ -3234,7 +3375,7 @@ static void read_state()
 	ippoolt itmp;
 	FILE *f;
 	char magic[sizeof(DUMP_MAGIC) - 1];
-	u32 buf[2];
+	uint32_t buf[2];
 
 	if (!config->save_state)
 	{
@@ -3355,7 +3496,7 @@ static void read_state()
 static void dump_state()
 {
 	FILE *f;
-	u32 buf[2];
+	uint32_t buf[2];
 
 	if (!config->save_state)
 		return;
@@ -3403,7 +3544,7 @@ static void dump_state()
 	unlink(STATEFILE);
 }
 
-static void build_chap_response(char *challenge, u8 id, u16 challenge_length, char **challenge_response)
+static void build_chap_response(char *challenge, uint8_t id, uint16_t challenge_length, char **challenge_response)
 {
 	MD5_CTX ctx;
 	*challenge_response = NULL;
@@ -3598,7 +3739,7 @@ static void read_config_file()
 int sessionsetup(tunnelidt t, sessionidt s)
 {
 	// A session now exists, set it up
-	ipt ip;
+	in_addr_t ip;
 	char *user;
 	sessionidt i;
 	int r;
@@ -3607,16 +3748,16 @@ int sessionsetup(tunnelidt t, sessionidt s)
 
 	LOG(3, s, t, "Doing session setup for session\n");
 
-	if (!session[s].ip || session[s].ip == 0xFFFFFFFE)
+	if (!session[s].ip)
 	{
 		assign_ip_address(s);
 		if (!session[s].ip)
 		{
-			LOG(0, s, t, "   No IP allocated. The IP address pool is FULL!\n");
+			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",
+		LOG(3, s, t, "   No IP allocated.  Assigned %s from pool\n",
 			fmtaddr(htonl(session[s].ip), 0));
 	}
 
@@ -3807,8 +3948,8 @@ int load_session(sessionidt s, sessiont *new)
 					// for walking the sessions to forward byte counts to the master.
 		config->cluster_highest_sessionid = s;
 
-	// TEMP: old session struct used a u32 to define the throttle
-	// speed for both up/down, new uses a u16 for each.  Deal with
+	// TEMP: old session struct used a uint32_t to define the throttle
+	// speed for both up/down, new uses a uint16_t 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;
@@ -3997,7 +4138,7 @@ static void plugins_done()
 		run_plugin_done(p);
 }
 
-static void processcontrol(u8 * buf, int len, struct sockaddr_in *addr, int alen)
+static void processcontrol(uint8_t * buf, int len, struct sockaddr_in *addr, int alen)
 {
 	struct nsctl request;
 	struct nsctl response;
@@ -4205,7 +4346,7 @@ void become_master(void)
 	{
 		for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
 		{
-			if (!session[s].tunnel) // Not an in-use session.
+			if (!session[s].opened) // Not an in-use session.
 				continue;
 
 			run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
@@ -4237,7 +4378,7 @@ int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc
 	for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
 	{
 		int idle;
-		if (!session[s].tunnel)
+		if (!session[s].opened)
 			continue;
 
 		idle = time_now - session[s].last_packet;
@@ -4275,7 +4416,7 @@ int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc
 	for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
 	{
 		int open = 0, d;
-		if (!session[s].tunnel)
+		if (!session[s].opened)
 			continue;
 
 		d = time_now - session[s].opened;
@@ -4309,16 +4450,16 @@ int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc
  *
  * Based on code from rp-l2tpd by Roaring Penguin Software Inc.
  */
-static int unhide_avp(u8 *avp, tunnelidt t, sessionidt s, u16 length)
+static int unhide_avp(uint8_t *avp, tunnelidt t, sessionidt s, uint16_t length)
 {
 	MD5_CTX ctx;
-	u8 *cursor;
-	u8 digest[16];
-	u8 working_vector[16];
+	uint8_t *cursor;
+	uint8_t digest[16];
+	uint8_t working_vector[16];
 	uint16_t hidden_length;
-	u8 type[2];
+	uint8_t type[2];
 	size_t done, todo;
-	u8 *output;
+	uint8_t *output;
 
 	// Find the AVP type.
 	type[0] = *(avp + 4);
@@ -4373,7 +4514,7 @@ static int unhide_avp(u8 *avp, tunnelidt t, sessionidt s, u16 length)
 	return hidden_length + 6;
 }
 
-static int ip_filter_port(ip_filter_portt *p, portt port)
+static int ip_filter_port(ip_filter_portt *p, uint16_t port)
 {
 	switch (p->op)
 	{
@@ -4387,7 +4528,7 @@ static int ip_filter_port(ip_filter_portt *p, portt port)
 	return 0;
 }
 
-static int ip_filter_flag(u8 op, u8 sflags, u8 cflags, u8 flags)
+static int ip_filter_flag(uint8_t op, uint8_t sflags, uint8_t cflags, uint8_t flags)
 {
 	switch (op)
 	{
@@ -4404,49 +4545,48 @@ static int ip_filter_flag(u8 op, u8 sflags, u8 cflags, u8 flags)
 	return 0;
 }
 
-int ip_filter(u8 *buf, int len, u8 filter)
+int ip_filter(uint8_t *buf, int len, uint8_t filter)
 {
-	u16 frag_offset;
-	u8 proto;
-    	ipt src_ip;
-	ipt dst_ip;
-	portt src_port = 0;
-	portt dst_port = 0;
-	u8 flags = 0;
+	uint16_t frag_offset;
+	uint8_t proto;
+    	in_addr_t src_ip;
+	in_addr_t dst_ip;
+	uint16_t src_port = 0;
+	uint16_t dst_port = 0;
+	uint8_t flags = 0;
 	ip_filter_rulet *rule;
 
     	if (len < 20) // up to end of destination address
 		return 0;
 
-	if (*buf >> 4) // IPv4
+	if ((*buf >> 4) != 4) // IPv4
 		return 0;
 
-
-	frag_offset = ntohs(*(u16 *) (buf + 0)) & 0x1fff;
+	frag_offset = ntohs(*(uint16_t *) (buf + 6)) & 0x1fff;
 	proto = buf[9];
-	src_ip = *(u32 *) (buf + 12);
-	dst_ip = *(u32 *) (buf + 16);
+	src_ip = *(in_addr_t *) (buf + 12);
+	dst_ip = *(in_addr_t *) (buf + 16);
 
 	if (frag_offset == 0 && (proto == IPPROTO_TCP || proto == IPPROTO_UDP))
 	{
-	    	int l = buf[0] & 0xf;
+		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));
+		src_port = ntohs(*(uint16_t *) (buf + l));
+		dst_port = ntohs(*(uint16_t *) (buf + l + 2));
 		if (proto == IPPROTO_TCP)
 		{
-		    	if (len < l + 15) // flags
+		    	if (len < l + 14) // flags
 				return 0;
 
-			flags = buf[l + 14] & 0x3f;
+			flags = buf[l + 13] & 0x3f;
 		}
 	}
 
 	for (rule = ip_filters[filter].rules; rule->action; rule++)
 	{
-		if (proto && proto != rule->proto)
+		if (rule->proto != IPPROTO_IP && proto != rule->proto)
 			continue;
 
 		if (rule->src_wild != INADDR_BROADCAST &&