set a default limit
[l2tpns.git] / l2tpns.c
index 127d515..733ca6d 100644 (file)
--- a/l2tpns.c
+++ b/l2tpns.c
@@ -4,7 +4,7 @@
 // Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced
 // vim: sw=8 ts=8
 
-char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.78 2005/01/13 07:57:36 bodea Exp $";
+char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.108 2005/06/04 15:42:35 bodea Exp $";
 
 #include <arpa/inet.h>
 #include <assert.h>
@@ -19,6 +19,7 @@ char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.78 2005/01/13 07:57:36 bodea Exp
 #include <sys/mman.h>
 #include <netdb.h>
 #include <netinet/in.h>
+#include <netinet/ip6.h>
 #include <stdarg.h>
 #include <stdlib.h>
 #include <stdio.h>
@@ -51,7 +52,7 @@ char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.78 2005/01/13 07:57:36 bodea Exp
 
 #ifdef BGP
 #include "bgp.h"
-#endif /* BGP */
+#endif
 
 // Globals
 configt *config = NULL;                // all configuration
@@ -62,19 +63,25 @@ int clifd = -1;                     // Socket listening for CLI connections.
 int snoopfd = -1;              // UDP file handle for sending out intercept data
 int *radfds = NULL;            // RADIUS requests file handles
 int ifrfd = -1;                        // File descriptor for routing, etc
-static int rand_fd = -1;       // Random data source
+int ifr6fd = -1;               // File descriptor for IPv6 routing, etc
+int rand_fd = -1;              // Random data source
+int cluster_sockfd = -1;       // Intra-cluster communications socket.
+int epollfd = -1;              // event polling
 time_t basetime = 0;           // base clock
 char hostname[1000] = "";      // us.
-static uint32_t sessionid = 0; // session id for radius accounting
+static int tunidx;             // ifr_ifindex of tun device
 static int syslog_log = 0;     // are we logging to syslog
-static FILE *log_stream = NULL;        // file handle for direct logging (i.e. direct into file, not via syslog).
-extern int cluster_sockfd;     // Intra-cluster communications socket.
-uint32_t last_id = 0;          // Last used PPP SID. Can I kill this?? -- mo
+static FILE *log_stream = 0;   // file handle for direct logging (i.e. direct into file, not via syslog).
+uint32_t last_id = 0;          // Unique ID for radius accounting
 
 struct cli_session_actions *cli_session_actions = NULL;        // Pending session changes requested by CLI
 struct cli_tunnel_actions *cli_tunnel_actions = NULL;  // Pending tunnel changes required by CLI
 
 static void *ip_hash[256];     // Mapping from IP address to session structures.
+struct ipv6radix {
+       int sess;
+       struct ipv6radix *branch;
+} ipv6_hash[256];              // Mapping from IPv6 address to session structures.
 
 // Traffic counters.
 static uint32_t udp_rx = 0, udp_rx_pkt = 0, udp_tx = 0;
@@ -84,7 +91,7 @@ uint32_t eth_tx = 0;
 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.
+char main_quit = 0;                    // True if we're in the process of exiting.
 linked_list *loaded_plugins;
 linked_list *plugins[MAX_PLUGIN_TYPES];
 
@@ -99,14 +106,15 @@ config_descriptt config_values[] = {
        CONFIG("l2tp_secret", l2tpsecret, STRING),
        CONFIG("primary_dns", default_dns1, IPv4),
        CONFIG("secondary_dns", default_dns2, IPv4),
-       CONFIG("save_state", save_state, BOOL),
        CONFIG("primary_radius", radiusserver[0], IPv4),
        CONFIG("secondary_radius", radiusserver[1], IPv4),
        CONFIG("primary_radius_port", radiusport[0], SHORT),
        CONFIG("secondary_radius_port", radiusport[1], SHORT),
        CONFIG("radius_accounting", radius_accounting, BOOL),
+       CONFIG("radius_interim", radius_interim, INT),
        CONFIG("radius_secret", radiussecret, STRING),
        CONFIG("radius_authtypes", radius_authtypes_s, STRING),
+       CONFIG("allow_duplicate_users", allow_duplicate_users, BOOL),
        CONFIG("bind_address", bind_address, IPv4),
        CONFIG("peer_address", peer_address, IPv4),
        CONFIG("send_garp", send_garp, BOOL),
@@ -115,7 +123,6 @@ config_descriptt config_values[] = {
        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),
@@ -125,6 +132,8 @@ config_descriptt config_values[] = {
        CONFIG("cluster_interface", cluster_interface, STRING),
        CONFIG("cluster_hb_interval", cluster_hb_interval, INT),
        CONFIG("cluster_hb_timeout", cluster_hb_timeout, INT),
+       CONFIG("cluster_master_min_adv", cluster_master_min_adv, INT),
+       CONFIG("ipv6_prefix", ipv6_prefix, IPv6),
        { NULL, 0, 0, 0 },
 };
 
@@ -163,6 +172,7 @@ struct Tringbuffer *ringbuffer = NULL;
 
 static void cache_ipmap(in_addr_t ip, int s);
 static void uncache_ipmap(in_addr_t ip);
+static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s);
 static void free_ip_address(sessionidt s);
 static void dump_acct_info(int all);
 static void sighup_handler(int sig);
@@ -170,8 +180,6 @@ static void sigalrm_handler(int sig);
 static void sigterm_handler(int sig);
 static void sigquit_handler(int sig);
 static void sigchild_handler(int sig);
-static void read_state(void);
-static void dump_state(void);
 static void build_chap_response(char *challenge, uint8_t id, uint16_t challenge_length, char **challenge_response);
 static void update_config(void);
 static void read_config_file(void);
@@ -181,13 +189,17 @@ static int remove_plugin(char *plugin_name);
 static void plugins_done(void);
 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen);
 static tunnelidt new_tunnel(void);
-static int unhide_avp(uint8_t *avp, tunnelidt t, sessionidt s, uint16_t length);
+static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len);
 
-// return internal time (10ths since process startup)
-static clockt now(void)
+// on slaves, alow BGP to withdraw cleanly before exiting
+#define QUIT_DELAY     5
+
+// return internal time (10ths since process startup), set f if given
+static clockt now(double *f)
 {
        struct timeval t;
        gettimeofday(&t, 0);
+       if (f) *f = t.tv_sec + t.tv_usec / 1000000.0;
        return (t.tv_sec - basetime) * 10 + t.tv_usec / 100000 + 1;
 }
 
@@ -197,7 +209,7 @@ static clockt now(void)
 clockt backoff(uint8_t try)
 {
        if (try > 5) try = 5;                  // max backoff
-       return now() + 10 * (1 << try);
+       return now(NULL) + 10 * (1 << try);
 }
 
 
@@ -291,6 +303,16 @@ void _log_hex(int level, const char *title, const char *data, int maxsize)
        }
 }
 
+// update a counter, accumulating 2^32 wraps
+void increment_counter(uint32_t *counter, uint32_t *wrap, uint32_t delta)
+{
+       uint32_t new = *counter + delta;
+       if (new < *counter)
+               (*wrap)++;
+
+       *counter = new;
+}
+
 // initialise the random generator
 static void initrandom(char *source)
 {
@@ -421,11 +443,61 @@ static void routeset(sessionidt s, in_addr_t ip, in_addr_t mask, in_addr_t gw, i
        }
 }
 
+void route6set(sessionidt s, struct in6_addr ip, int prefixlen, int add)
+{
+       struct in6_rtmsg rt;
+       char ipv6addr[INET6_ADDRSTRLEN];
+
+       if (ifr6fd < 0)
+       {
+               LOG(0, 0, 0, "Asked to set IPv6 route, but IPv6 not setup.\n");
+               return;
+       }
+
+       memset(&rt, 0, sizeof(rt));
+
+       memcpy(&rt.rtmsg_dst, &ip, sizeof(struct in6_addr));
+       rt.rtmsg_dst_len = prefixlen;
+       rt.rtmsg_metric = 1;
+       rt.rtmsg_flags = RTF_UP;
+       rt.rtmsg_ifindex = tunidx;
+
+       LOG(1, 0, 0, "Route %s %s/%d\n",
+           add ? "add" : "del",
+           inet_ntop(AF_INET6, &ip, ipv6addr, INET6_ADDRSTRLEN),
+           prefixlen);
+
+       if (ioctl(ifr6fd, add ? SIOCADDRT : SIOCDELRT, (void *) &rt) < 0)
+               LOG(0, 0, 0, "route6set() error in ioctl: %s\n",
+                               strerror(errno));
+
+       // FIXME: need to add BGP routing (RFC2858)
+
+       if (s)
+       {
+               if (!add)       // Are we deleting a route?
+                       s = 0;  // Caching the session as '0' is the same as uncaching.
+
+               cache_ipv6map(ip, prefixlen, s);
+       }
+       
+       return;
+}
+
+// defined in linux/ipv6.h, but tricky to include from user-space
+// TODO: move routing to use netlink rather than ioctl
+struct in6_ifreq {
+       struct in6_addr ifr6_addr;
+       __u32 ifr6_prefixlen;
+       unsigned int ifr6_ifindex;
+};
+
 //
 // Set up TUN interface
 static void inittun(void)
 {
        struct ifreq ifr;
+       struct in6_ifreq ifr6;
        struct sockaddr_in sin = {0};
        memset(&ifr, 0, sizeof(ifr));
        ifr.ifr_flags = IFF_TUN;
@@ -471,6 +543,42 @@ static void inittun(void)
                LOG(0, 0, 0, "Error setting tun flags: %s\n", strerror(errno));
                exit(1);
        }
+       if (ioctl(ifrfd, SIOCGIFINDEX, (void *) &ifr) < 0)
+       {
+               LOG(0, 0, 0, "Error getting tun ifindex: %s\n", strerror(errno));
+               exit(1);
+       }
+       tunidx = ifr.ifr_ifindex;
+
+       // Only setup IPv6 on the tun device if we have a configured prefix
+       if (config->ipv6_prefix.s6_addr[0] > 0) {
+               ifr6fd = socket(PF_INET6, SOCK_DGRAM, 0);
+
+               // Link local address is FE80::1
+               memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
+               ifr6.ifr6_addr.s6_addr[0] = 0xFE;
+               ifr6.ifr6_addr.s6_addr[1] = 0x80;
+               ifr6.ifr6_addr.s6_addr[15] = 1;
+               ifr6.ifr6_prefixlen = 64;
+               ifr6.ifr6_ifindex = ifr.ifr_ifindex;
+               if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
+               {
+                       LOG(0, 0, 0, "Error setting tun IPv6 link local address:"
+                               " %s\n", strerror(errno));
+               }
+
+               // Global address is prefix::1
+               memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
+               ifr6.ifr6_addr = config->ipv6_prefix;
+               ifr6.ifr6_addr.s6_addr[15] = 1;
+               ifr6.ifr6_prefixlen = 64;
+               ifr6.ifr6_ifindex = ifr.ifr_ifindex;
+               if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
+               {
+                       LOG(0, 0, 0, "Error setting tun IPv6 global address: %s\n",
+                               strerror(errno));
+               }
+       }
 }
 
 // set up UDP port
@@ -537,17 +645,62 @@ static int lookup_ipmap(in_addr_t ip)
        return (int) (intptr_t) d[(size_t) *a];
 }
 
+static int lookup_ipv6map(struct in6_addr ip)
+{
+       struct ipv6radix *curnode;
+       int i;
+       int s;
+       char ipv6addr[INET6_ADDRSTRLEN];
+
+       curnode = &ipv6_hash[ip.s6_addr[0]];
+       i = 1;
+       s = curnode->sess;
+
+       while (s == 0 && i < 15 && curnode->branch != NULL)
+       {
+               curnode = &curnode->branch[ip.s6_addr[i]];
+               s = curnode->sess;
+               i++;
+       }
+
+       LOG(4, s, session[s].tunnel, "Looking up address %s and got %d\n",
+                       inet_ntop(AF_INET6, &ip, ipv6addr,
+                               INET6_ADDRSTRLEN),
+                       s);
+
+       return s;
+}
+
 sessionidt sessionbyip(in_addr_t ip)
 {
        int s = lookup_ipmap(ip);
        CSTAT(sessionbyip);
 
-       if (s > 0 && s < MAXSESSION && session[s].tunnel)
+       if (s > 0 && s < MAXSESSION && session[s].opened)
                return (sessionidt) s;
 
        return 0;
 }
 
+sessionidt sessionbyipv6(struct in6_addr ip)
+{
+       int s;
+       CSTAT(sessionbyipv6);
+
+       if (!memcmp(&config->ipv6_prefix, &ip, 8) ||
+               (ip.s6_addr[0] == 0xFE && ip.s6_addr[1] == 0x80 &&
+                (ip.s6_addr16[1] == ip.s6_addr16[2] == ip.s6_addr16[3] == 0))) {
+               s = lookup_ipmap(*(in_addr_t *) &ip.s6_addr[8]);
+       } else {
+               s = lookup_ipv6map(ip);
+       }
+
+       if (s > 0 && s < MAXSESSION && session[s].opened)
+               return s;
+
+       return 0;
+}
+
 //
 // Take an IP address in HOST byte order and
 // add it to the sessionid by IP cache.
@@ -587,6 +740,42 @@ static void uncache_ipmap(in_addr_t ip)
        cache_ipmap(ip, 0);     // Assign it to the NULL session.
 }
 
+static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s)
+{
+       int i;
+       int bytes;
+       struct ipv6radix *curnode;
+       char ipv6addr[INET6_ADDRSTRLEN];
+
+       curnode = &ipv6_hash[ip.s6_addr[0]];
+
+       bytes = prefixlen >> 3;
+       i = 1;
+       while (i < bytes) {
+               if (curnode->branch == NULL)
+               {
+                       if (!(curnode->branch = calloc(256,
+                                       sizeof (struct ipv6radix))))
+                               return;
+               }
+               curnode = &curnode->branch[ip.s6_addr[i]];
+               i++;
+       }
+
+       curnode->sess = s;
+
+       if (s > 0)
+               LOG(4, s, session[s].tunnel, "Caching ip address %s/%d\n",
+                               inet_ntop(AF_INET6, &ip, ipv6addr, 
+                                       INET6_ADDRSTRLEN),
+                               prefixlen);
+       else if (s == 0)
+               LOG(4, 0, 0, "Un-caching ip address %s/%d\n",
+                               inet_ntop(AF_INET6, &ip, ipv6addr, 
+                                       INET6_ADDRSTRLEN),
+                               prefixlen);
+}
+
 //
 // CLI list to dump current ipcache.
 //
@@ -642,8 +831,11 @@ sessionidt sessionbyuser(char *username)
        int s;
        CSTAT(sessionbyuser);
 
-       for (s = 1; s < MAXSESSION ; ++s)
+       for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
        {
+               if (!session[s].opened)
+                       continue;
+
                if (session[s].walled_garden)
                        continue;               // Skip walled garden users.
 
@@ -685,17 +877,16 @@ void send_garp(in_addr_t ip)
        sendarp(ifr.ifr_ifindex, mac, ip);
 }
 
-// Find session by username, 0 for not found
 static sessiont *sessiontbysessionidt(sessionidt s)
 {
-       if (!s || s > MAXSESSION) return NULL;
+       if (!s || s >= MAXSESSION) return NULL;
        return &session[s];
 }
 
 static sessionidt sessionidtbysessiont(sessiont *s)
 {
        sessionidt val = s-session;
-       if (s < session || val > MAXSESSION) return 0;
+       if (s < session || val >= MAXSESSION) return 0;
        return val;
 }
 
@@ -822,7 +1013,8 @@ static void processipout(uint8_t * 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(*(in_addr_t *)(buf + 12), 0));
-                       host_unreachable(*(in_addr_t *)(buf + 12), *(uint16_t *)(buf + 4), ip, buf, (len < 64) ? 64 : len);
+                       host_unreachable(*(in_addr_t *)(buf + 12), *(uint16_t *)(buf + 4),
+                               config->bind_address ? config->bind_address : my_address, buf, len);
                }
                return;
        }
@@ -857,7 +1049,7 @@ static void processipout(uint8_t * buf, int len)
                        {
                                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_out, sess_local[s].packets_dropped,
+                                       sess_local[s].packets_dropped, sess_local[s].packets_out,
                                        fmtaddr(ip, 0), sp->throttle_out ? "throttled " : "",
                                        sp->user);
                        }
@@ -901,11 +1093,124 @@ static void processipout(uint8_t * buf, int len)
        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
+       increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
+       sp->cout_delta += len;
+       sp->pout++;
+       udp_tx += len;
+
+       sess_local[s].cout += len;      // To send to master..
+       sess_local[s].pout++;
+}
+
+// process outgoing (to tunnel) IPv6
+//
+static void processipv6out(uint8_t * buf, int len)
+{
+       sessionidt s;
+       sessiont *sp;
+       tunnelidt t;
+       in_addr_t ip;
+       struct in6_addr ip6;
+
+       char *data = buf;       // Keep a copy of the originals.
+       int size = len;
+
+       uint8_t b[MAXETHER + 20];
+
+       CSTAT(processipv6out);
+
+       if (len < MIN_IP_SIZE)
+       {
+               LOG(1, 0, 0, "Short IPv6, %d bytes\n", len);
+               STAT(tunnel_tx_errors);
+               return;
+       }
+       if (len >= MAXETHER)
+       {
+               LOG(1, 0, 0, "Oversize IPv6 packet %d bytes\n", len);
+               STAT(tunnel_tx_errors);
+               return;
+       }
+
+       // Skip the tun header
+       buf += 4;
+       len -= 4;
+
+       // Got an IP header now
+       if (*(uint8_t *)(buf) >> 4 != 6)
+       {
+               LOG(1, 0, 0, "IP: Don't understand anything except IPv6\n");
+               return;
+       }
+
+       ip6 = *(struct in6_addr *)(buf+24);
+       s = sessionbyipv6(ip6);
+
+       if (s == 0)
+       {
+               ip = *(uint32_t *)(buf + 32);
+               s = sessionbyip(ip);
+       }
+       
+       if (s == 0)
+       {
+               // Is this a packet for a session that doesn't exist?
+               static int rate = 0;    // Number of ICMP packets we've sent this second.
+               static int last = 0;    // Last time we reset the ICMP packet counter 'rate'.
+
+               if (last != time_now)
+               {
+                       last = time_now;
+                       rate = 0;
+               }
+
+               if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
+               {
+                       // FIXME: Should send icmp6 host unreachable
+               }
+               return;
+       }
+       t = session[s].tunnel;
+       sp = &session[s];
+
+       // FIXME: add DoS prevention/filters?
+
+       if (sp->tbf_out)
+       {
+               // Are we throttling this session?
+               if (config->cluster_iam_master)
+                       tbf_queue_packet(sp->tbf_out, data, size);
+               else
+                       master_throttle_packet(sp->tbf_out, data, size);
+               return;
+       }
+       else if (sp->walled_garden && !config->cluster_iam_master)
+       {
+               // We are walled-gardening this
+               master_garden_packet(s, data, size);
+               return;
+       }
+
+       LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
+
+       // Add on L2TP header
+       {
+               uint8_t *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIPV6);
+               if (!p) return;
+               tunnelsend(b, len + (p-b), t); // send it...
+       }
+
+       // Snooping this session, send it to intercept box
+       if (sp->snoop_ip && sp->snoop_port)
+               snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
+
+       increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
+       sp->cout_delta += len;
        sp->pout++;
        udp_tx += len;
+
        sess_local[s].cout += len;      // To send to master..
+       sess_local[s].pout++;
 }
 
 //
@@ -951,11 +1256,13 @@ static void send_ipout(sessionidt s, uint8_t *buf, int len)
        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
+       increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
+       sp->cout_delta += len;
        sp->pout++;
        udp_tx += len;
+
        sess_local[s].cout += len;      // To send to master..
+       sess_local[s].pout++;
 }
 
 // add an AVP (16 bit)
@@ -980,7 +1287,7 @@ static void control32(controlt * c, uint16_t avp, uint32_t val, uint8_t m)
        c->length += 10;
 }
 
-// add an AVP (32 bit)
+// add an AVP (string)
 static void controls(controlt * c, uint16_t avp, char *val, uint8_t m)
 {
        uint16_t l = ((m ? 0x8000 : 0) + strlen(val) + 6);
@@ -1039,11 +1346,11 @@ static void controlnull(tunnelidt t)
 }
 
 // add a control message to a tunnel, and send if within window
-static void controladd(controlt * c, tunnelidt t, sessionidt s)
+static void controladd(controlt * c, tunnelidt t, sessionidt far)
 {
        *(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 + 6) = htons(far); // session
        *(uint16_t *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
        tunnel[t].ns++;              // advance sequence
        // link in message in to queue
@@ -1075,7 +1382,7 @@ 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)
@@ -1111,9 +1418,9 @@ void throttle_session(sessionidt s, int rate_in, int rate_out)
 }
 
 // add/remove filters from session (-1 = no change)
-void filter_session(sessionidt s, int filter_in, int filter_out)
+static void filter_session(sessionidt s, int filter_in, int filter_out)
 {
-       if (!session[s].tunnel)
+       if (!session[s].opened)
                return; // No-one home.
 
        if (!*session[s].user)
@@ -1149,16 +1456,16 @@ void filter_session(sessionidt s, int filter_in, int filter_out)
 }
 
 // start tidy shutdown of session
-void sessionshutdown(sessionidt s, char *reason)
+void sessionshutdown(sessionidt s, char *reason, int result, int error)
 {
        int walled_garden = session[s].walled_garden;
 
 
        CSTAT(sessionshutdown);
 
-       if (!session[s].tunnel)
+       if (!session[s].opened)
        {
-               LOG(3, s, session[s].tunnel, "Called sessionshutdown on a session with no tunnel.\n");
+               LOG(3, s, session[s].tunnel, "Called sessionshutdown on an unopened session.\n");
                return;                   // not a live session
        }
 
@@ -1169,25 +1476,21 @@ void sessionshutdown(sessionidt s, char *reason)
                run_plugins(PLUGIN_KILL_SESSION, &data);
        }
 
-       if (session[s].opened && !walled_garden && !session[s].die)
+       if (session[s].ip && !walled_garden && !session[s].die)
        {
                // RADIUS Stop message
-               uint16_t r = session[s].radius;
+               uint16_t r = sess_local[s].radius;
                if (!r)
+                       r = radiusnew(s);
+
+               if (r)
                {
-                       if (!(r = radiusnew(s)))
-                       {
-                               LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
-                               STAT(radius_overflow);
-                       }
-                       else
-                       {
-                               random_data(radius[r].auth, sizeof(radius[r].auth));
-                       }
+                       // stop, if not already trying
+                       if (radius[r].state != RADIUSSTOP)
+                               radiussend(r, RADIUSSTOP);
                }
-
-               if (r && radius[r].state != RADIUSSTOP)
-                       radiussend(r, RADIUSSTOP); // stop, if not already trying
+               else
+                       LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
 
                // Save counters to dump to accounting file
                if (*config->accounting_dir && shut_acct_n < sizeof(shut_acct) / sizeof(*shut_acct))
@@ -1215,20 +1518,34 @@ void sessionshutdown(sessionidt s, char *reason)
                }
                else
                        free_ip_address(s);
+
+               // unroute IPv6, if setup
+               if (session[s].flags & SF_IPV6_ROUTED)
+                       route6set(s, session[s].ipv6route, session[s].ipv6prefixlen, 0);
        }
 
        if (session[s].throttle_in || session[s].throttle_out) // Unthrottle if throttled.
                throttle_session(s, 0, 0);
 
+       if (result)
        {                            // Send CDN
                controlt *c = controlnew(14); // sending CDN
-               control16(c, 1, 3, 1);    // result code (admin reasons - TBA make error, general error, add message
+               if (error)
+               {
+                       char buf[4];
+                       *(uint16_t *) buf     = htons(result);
+                       *(uint16_t *) (buf+2) = htons(error);
+                       controlb(c, 1, buf, 4, 1);
+               }
+               else
+                       control16(c, 1, result, 1);
+
                control16(c, 14, s, 1);   // assigned session (our end)
-               controladd(c, session[s].tunnel, s); // send the message
+               controladd(c, session[s].tunnel, session[s].far); // send the message
        }
 
        if (!session[s].die)
-               session[s].die = now() + 150; // Clean up in 15 seconds
+               session[s].die = TIME + 150; // Clean up in 15 seconds
 
        // update filter refcounts
        if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
@@ -1240,7 +1557,7 @@ void sessionshutdown(sessionidt s, char *reason)
 void sendipcp(tunnelidt t, sessionidt s)
 {
        uint8_t buf[MAXCONTROL];
-       uint16_t r = session[s].radius;
+       uint16_t r = sess_local[s].radius;
        uint8_t *q;
 
        CSTAT(sendipcp);
@@ -1248,6 +1565,12 @@ void sendipcp(tunnelidt t, sessionidt s)
        if (!r)
                r = radiusnew(s);
 
+       if (!r)
+       {
+               sessionshutdown(s, "No free RADIUS sessions for IPCP", 3, 0);
+               return;
+       }
+
        if (radius[r].state != RADIUSIPCP)
        {
                radius[r].state = RADIUSIPCP;
@@ -1258,7 +1581,7 @@ void sendipcp(tunnelidt t, sessionidt s)
        if (radius[r].try > 10)
        {
                radiusclear(r, s);      // Clear radius session.
-               sessionshutdown(s, "No reply on IPCP");
+               sessionshutdown(s, "No reply to IPCP.", 3, 0);
                return;
        }
 
@@ -1266,7 +1589,7 @@ void sendipcp(tunnelidt t, sessionidt s)
        if (!q) return;
 
        *q = ConfigReq;
-       q[1] = r << RADIUS_SHIFT;                    // 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
        *(uint16_t *) (q + 2) = htons(10);
        q[4] = 3;
        q[5] = 6;
@@ -1276,26 +1599,65 @@ void sendipcp(tunnelidt t, sessionidt s)
 
        tunnelsend(buf, 10 + (q - buf), t); // send it
        session[s].flags &= ~SF_IPCP_ACKED;     // Clear flag.
+
+       // If we have an IPv6 prefix length configured, assume we should
+       // try to negotiate an IPv6 session as well. Unless we've had a
+       // (N)ACK for IPV6CP.
+       if (config->ipv6_prefix.s6_addr[0] > 0 && 
+                       !(session[s].flags & SF_IPV6CP_ACKED) &&
+                       !(session[s].flags & SF_IPV6_NACKED))
+       {
+               q = makeppp(buf,sizeof(buf), 0, 0, t, s, PPPIPV6CP);
+               if (!q) return;
+
+               *q = ConfigReq;
+               q[1] = r >> RADIUS_SHIFT;               // ID, don't care, we
+                                                       // only send one type
+                                                       // of request
+               *(uint16_t *) (q + 2) = htons(14);
+               q[4] = 1;
+               q[5] = 10;
+               *(uint32_t *) (q + 6) = 0;              // We'll be prefix::1
+               *(uint32_t *) (q + 10) = 0;
+               q[13] = 1;
+
+               tunnelsend(buf, 14 + (q - buf), t);     // send it
+       }
+}
+
+static void sessionclear(sessionidt s)
+{
+       memset(&session[s], 0, sizeof(session[s]));
+       memset(&sess_local[s], 0, sizeof(sess_local[s]));
+       memset(&cli_session_actions[s], 0, sizeof(cli_session_actions[s]));
+
+       session[s].tunnel = T_FREE;     // Mark it as free.
+       session[s].next = sessionfree;
+       sessionfree = s;
 }
 
 // kill a session now
-static void sessionkill(sessionidt s, char *reason)
+void sessionkill(sessionidt s, char *reason)
 {
 
        CSTAT(sessionkill);
 
-       session[s].die = now();
-       sessionshutdown(s, reason);  // close radius/routes, etc.
-       if (session[s].radius)
-               radiusclear(session[s].radius, s); // cant send clean accounting data, session is killed
+       if (!session[s].opened) // not alive
+               return;
 
-       LOG(2, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
+       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;
+       }
 
-       memset(&session[s], 0, sizeof(session[s]));
-       session[s].tunnel = T_FREE;     // Mark it as free.
-       session[s].next = sessionfree;
-       sessionfree = s;
-       cli_session_actions[s].action = 0;
+       session[s].die = TIME;
+       sessionshutdown(s, reason, 3, 0);  // close radius/routes, etc.
+       if (sess_local[s].radius)
+               radiusclear(sess_local[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);
+       sessionclear(s);
        cluster_send_session(s);
 }
 
@@ -1326,19 +1688,19 @@ static void tunnelkill(tunnelidt t, char *reason)
                controlfree = c;
        }
        // kill sessions
-       for (s = 1; s < MAXSESSION; s++)
+       for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
                if (session[s].tunnel == t)
                        sessionkill(s, reason);
 
        // free tunnel
        tunnelclear(t);
        LOG(1, 0, t, "Kill tunnel %d: %s\n", t, reason);
-       cli_tunnel_actions[s].action = 0;
+       cli_tunnel_actions[t].action = 0;
        cluster_send_tunnel(t);
 }
 
 // shut down a tunnel cleanly
-static void tunnelshutdown(tunnelidt t, char *reason)
+static void tunnelshutdown(tunnelidt t, char *reason, int result, int error, char *msg)
 {
        sessionidt s;
 
@@ -1353,19 +1715,40 @@ static void tunnelshutdown(tunnelidt t, char *reason)
        LOG(1, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
 
        // close session
-       for (s = 1; s < MAXSESSION; s++)
+       for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
                if (session[s].tunnel == t)
-                       sessionshutdown(s, reason);
+                       sessionshutdown(s, reason, 3, 0);
 
        tunnel[t].state = TUNNELDIE;
-       tunnel[t].die = now() + 700; // Clean up in 70 seconds
+       tunnel[t].die = TIME + 700; // Clean up in 70 seconds
        cluster_send_tunnel(t);
        // TBA - should we wait for sessions to stop?
-       {                            // Send StopCCN
-               controlt *c = controlnew(4); // sending StopCCN
-               control16(c, 1, 1, 1);    // result code (admin reasons - TBA make error, general error, add message)
-               control16(c, 9, t, 1);    // assigned tunnel (our end)
-               controladd(c, t, 0);      // send the message
+       if (result) 
+       {
+               controlt *c = controlnew(4);    // sending StopCCN
+               if (error)
+               {
+                       char buf[64];
+                       int l = 4;
+                       *(uint16_t *) buf     = htons(result);
+                       *(uint16_t *) (buf+2) = htons(error);
+                       if (msg)
+                       {
+                               int m = strlen(msg);
+                               if (m + 4 > sizeof(buf))
+                                   m = sizeof(buf) - 4;
+
+                               memcpy(buf+4, msg, m);
+                               l += m;
+                       }
+
+                       controlb(c, 1, buf, l, 1);
+               }
+               else
+                       control16(c, 1, result, 1);
+
+               control16(c, 9, t, 1);          // assigned tunnel (our end)
+               controladd(c, t, 0);            // send the message
        }
 }
 
@@ -1440,13 +1823,12 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
        {                          // control
                uint16_t message = 0xFFFF;      // message type
                uint8_t fatal = 0;
-               uint8_t mandatorymessage = 0;
-               uint8_t chap = 0;               // if CHAP being used
+               uint8_t mandatory = 0;
+               uint8_t authtype = 0;           // proxy auth type
                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
 
@@ -1456,7 +1838,10 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
                        return;
                }
 
-               if ((*buf & 0xCA) != 0xC8)
+               // control messages must have bits 0x80|0x40|0x08
+               // (type, length and sequence) set, and bits 0x02|0x01
+               // (offset and priority) clear
+               if ((*buf & 0xCB) != 0xC8)
                {
                        LOG(1, s, t, "Bad control header %02X\n", *buf);
                        STAT(tunnel_rx_errors);
@@ -1566,71 +1951,111 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
                }
                if (l)
                {                     // if not a null message
+                       int result = 0;
+                       int error = 0;
+                       char *msg = 0;
+
                        // process AVPs
-                       while (l && !(fatal & 0x80))
+                       while (l && !(fatal & 0x80)) // 0x80 = mandatory AVP
                        {
                                uint16_t n = (ntohs(*(uint16_t *) p) & 0x3FF);
                                uint8_t *b = p;
                                uint8_t flags = *p;
                                uint16_t mtype;
-                               p += n;       // next
-                               if (l < n)
+                               if (n > l)
                                {
                                        LOG(1, s, t, "Invalid length in AVP\n");
                                        STAT(tunnel_rx_errors);
-                                       fatal = flags;
                                        return;
                                }
+                               p += n;       // next
                                l -= n;
+                               if (flags & 0x3C) // reserved bits, should be clear
+                               {
+                                       LOG(1, s, t, "Unrecognised AVP flags %02X\n", *b);
+                                       fatal = flags;
+                                       result = 2; // general error
+                                       error = 3; // reserved field non-zero
+                                       msg = 0;
+                                       continue; // next
+                               }
+                               b += 2;
+                               if (*(uint16_t *) (b))
+                               {
+                                       LOG(2, s, t, "Unknown AVP vendor %d\n", ntohs(*(uint16_t *) (b)));
+                                       fatal = flags;
+                                       result = 2; // general error
+                                       error = 6; // generic vendor-specific error
+                                       msg = "unsupported vendor-specific";
+                                       continue; // next
+                               }
+                               b += 2;
+                               mtype = ntohs(*(uint16_t *) (b));
+                               b += 2;
+                               n -= 6;
+
                                if (flags & 0x40)
                                {
+                                       uint16_t orig_len;
+
                                        // handle hidden AVPs
                                        if (!*config->l2tpsecret)
                                        {
                                                LOG(1, s, t, "Hidden AVP requested, but no L2TP secret.\n");
                                                fatal = flags;
+                                               result = 2; // general error
+                                               error = 6; // generic vendor-specific error
+                                               msg = "secret not specified";
                                                continue;
                                        }
                                        if (!session[s].random_vector_length)
                                        {
                                                LOG(1, s, t, "Hidden AVP requested, but no random vector.\n");
                                                fatal = flags;
+                                               result = 2; // general error
+                                               error = 6; // generic
+                                               msg = "no random vector";
+                                               continue;
+                                       }
+                                       if (n < 8)
+                                       {
+                                               LOG(2, s, t, "Short hidden AVP.\n");
+                                               fatal = flags;
+                                               result = 2; // general error
+                                               error = 2; // length is wrong
+                                               msg = 0;
                                                continue;
                                        }
+
                                        LOG(4, s, t, "Hidden AVP\n");
+
                                        // Unhide the AVP
-                                       n = unhide_avp(b, t, s, n);
-                                       if (n == 0)
+                                       unhide_value(b, n, mtype, session[s].random_vector, session[s].random_vector_length);
+
+                                       orig_len = ntohs(*(uint16_t *) b);
+                                       if (orig_len > n + 2)
                                        {
+                                               LOG(1, s, t, "Original length %d too long in hidden AVP of length %d; wrong secret?\n",
+                                                   orig_len, n);
+
                                                fatal = flags;
+                                               result = 2; // general error
+                                               error = 2; // length is wrong
+                                               msg = 0;
                                                continue;
                                        }
+
+                                       b += 2;
+                                       n = orig_len;
                                }
-                               if (*b & 0x3C)
-                               {
-                                       LOG(1, s, t, "Unrecognised AVP flags %02X\n", *b);
-                                       fatal = flags;
-                                       continue; // next
-                               }
-                               b += 2;
-                               if (*(uint16_t *) (b))
-                               {
-                                       LOG(2, s, t, "Unknown AVP vendor %d\n", ntohs(*(uint16_t *) (b)));
-                                       fatal = flags;
-                                       continue; // next
-                               }
-                               b += 2;
-                               mtype = ntohs(*(uint16_t *) (b));
-                               b += 2;
-                               n -= 6;
 
                                LOG(4, s, t, "   AVP %d (%s) len %d\n", mtype, avp_name(mtype), n);
                                switch (mtype)
                                {
                                case 0:     // message type
                                        message = ntohs(*(uint16_t *) b);
+                                       mandatory = flags & 0x80;
                                        LOG(4, s, t, "   Message type = %d (%s)\n", *b, l2tp_message_type(message));
-                                       mandatorymessage = flags;
                                        break;
                                case 1:     // result code
                                        {
@@ -1665,6 +2090,9 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
                                                {   // allow 0.0 and 1.0
                                                        LOG(1, s, t, "   Bad protocol version %04X\n", version);
                                                        fatal = flags;
+                                                       result = 5; // unspported protocol version
+                                                       error = 0x0100; // supported version
+                                                       msg = 0;
                                                        continue; // next
                                                }
                                        }
@@ -1683,14 +2111,14 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
 //                                     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);
+                                       memset(tunnel[t].hostname, 0, sizeof(tunnel[t].hostname));
+                                       memcpy(tunnel[t].hostname, b, (n < sizeof(tunnel[t].hostname)) ? n : sizeof(tunnel[t].hostname) - 1);
                                        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, sizeof(tunnel[t].vendor));
-                                       memcpy(tunnel[t].vendor, b, (n >= sizeof(tunnel[t].vendor) - 1) ? sizeof(tunnel[t].vendor) - 1 : n);
+                                       memcpy(tunnel[t].vendor, b, (n < sizeof(tunnel[t].vendor)) ? n : sizeof(tunnel[t].vendor) - 1);
                                        LOG(4, s, t, "   Vendor name = \"%s\"\n", tunnel[t].vendor);
                                        break;
                                case 9:     // assigned tunnel
@@ -1730,13 +2158,13 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
                                        // TBA
                                        break;
                                case 21:    // called number
-                                       memset(called, 0, MAXTEL);
-                                       memcpy(called, b, (n >= MAXTEL) ? (MAXTEL-1) : n);
+                                       memset(called, 0, sizeof(called));
+                                       memcpy(called, b, (n < sizeof(called)) ? n : sizeof(called) - 1);
                                        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);
+                                       memset(calling, 0, sizeof(calling));
+                                       memcpy(calling, b, (n < sizeof(calling)) ? n : sizeof(calling) - 1);
                                        LOG(4, s, t, "   Calling <%s>\n", calling);
                                        break;
                                case 23:    // subtype
@@ -1749,8 +2177,9 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
                                        else
                                        {
                                                // AS5300s send connect speed as a string
-                                               char tmp[30] = {0};
-                                               memcpy(tmp, b, (n >= 30) ? 30 : n);
+                                               char tmp[30];
+                                               memset(tmp, 0, sizeof(tmp));
+                                               memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
                                                session[s].tx_connect_speed = atol(tmp);
                                        }
                                        LOG(4, s, t, "   TX connect speed <%u>\n", session[s].tx_connect_speed);
@@ -1763,8 +2192,9 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
                                        else
                                        {
                                                // AS5300s send connect speed as a string
-                                               char tmp[30] = {0};
-                                               memcpy(tmp, b, (n >= 30) ? 30 : n);
+                                               char tmp[30];
+                                               memset(tmp, 0, sizeof(tmp));
+                                               memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
                                                session[s].rx_connect_speed = atol(tmp);
                                        }
                                        LOG(4, s, t, "   RX connect speed <%u>\n", session[s].rx_connect_speed);
@@ -1779,47 +2209,51 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
                                        {
                                                uint16_t atype = ntohs(*(uint16_t *)b);
                                                LOG(4, s, t, "   Proxy Auth Type %d (%s)\n", atype, auth_type(atype));
-                                               requestchap = (atype == 2);
+                                               if (atype == 2)
+                                                       authtype = AUTHCHAP;
+                                               else if (atype == 3)
+                                                       authtype = AUTHPAP;
+
                                                break;
                                        }
                                case 30:    // Proxy Authentication Name
                                        {
-                                               char authname[64] = {0};
-                                               memcpy(authname, b, (n > 63) ? 63 : n);
+                                               char authname[64];
+                                               memset(authname, 0, sizeof(authname));
+                                               memcpy(authname, b, (n < sizeof(authname)) ? n : sizeof(authname) - 1);
                                                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, s, t, "   Proxy Auth Challenge\n");
+                                               if (sess_local[s].radius)
+                                                       memcpy(radius[sess_local[s].radius].auth, b, 16);
                                                break;
                                        }
                                case 32:    // Proxy Authentication ID
                                        {
                                                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;
+                                               if (sess_local[s].radius)
+                                                       radius[sess_local[s].radius].id = authid;
                                                break;
                                        }
                                case 33:    // Proxy Authentication Response
-                                       {
-                                               char authresp[64] = {0};
-                                               memcpy(authresp, b, (n > 63) ? 63 : n);
-                                               LOG(4, s, t, "   Proxy Auth Response\n");
-                                               break;
-                                       }
-                               case 27:    // last send lcp
+                                       LOG(4, s, t, "   Proxy Auth Response\n");
+                                       break;
+                               case 27:    // last sent lcp
                                        {        // find magic number
                                                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(*(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 == 3 && p[1] == 4 && *(uint16_t *) (p + 2) == htons(PPPPAP)) // Authentication-Protocol (PAP)
+                                                               authtype = AUTHPAP;
+                                                       else if (*p == 3 && p[1] == 5 && *(uint16_t *) (p + 2) == htons(PPPCHAP) && p[4] == 5) // Authentication-Protocol (CHAP)
+                                                               authtype = AUTHCHAP;
                                                        else if (*p == 7) // Protocol-Field-Compression
                                                                aflags |= SESSIONPFC;
                                                        else if (*p == 8) // Address-and-Control-Field-Compression
@@ -1841,14 +2275,20 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
                                        session[s].random_vector_length = n;
                                        break;
                                default:
-                                       LOG(2, s, t, "   Unknown AVP type %d\n", mtype);
-                                       fatal = flags;
-                                       continue; // next
+                                       {
+                                               static char e[] = "unknown AVP 0xXXXX";
+                                               LOG(2, s, t, "   Unknown AVP type %d\n", mtype);
+                                               fatal = flags;
+                                               result = 2; // general error
+                                               error = 8; // unknown mandatory AVP
+                                               sprintf((msg = e) + 14, "%04x", mtype);
+                                               continue; // next
+                                       }
                                }
                        }
                        // process message
                        if (fatal & 0x80)
-                               tunnelshutdown(t, "Unknown Mandatory AVP");
+                               tunnelshutdown(t, "Invalid mandatory AVP", result, error, msg);
                        else
                                switch (message)
                                {
@@ -1860,7 +2300,7 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
                                                controls(c, 7, tunnel[t].hostname, 1); // host name (TBA)
                                                if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
                                                control16(c, 9, t, 1); // assigned tunnel
-                                               controladd(c, t, s); // send the resply
+                                               controladd(c, t, 0); // send the resply
                                        }
                                        tunnel[t].state = TUNNELOPENING;
                                        break;
@@ -1873,8 +2313,7 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
                                        break;
                                case 4:       // StopCCN
                                        controlnull(t); // ack
-                                       tunnelshutdown(t, "Stopped"); // Shut down cleanly
-                                       tunnelkill(t, "Stopped"); // Immediately force everything dead
+                                       tunnelshutdown(t, "Stopped", 0, 0, 0); // Shut down cleanly
                                        break;
                                case 6:       // HELLO
                                        controlnull(t); // simply ACK
@@ -1889,15 +2328,9 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
                                        // TBA
                                        break;
                                case 10:      // ICRQ
-                                       if (!sessionfree)
-                                       {
-                                               STAT(session_overflow);
-                                               tunnelshutdown(t, "No free sessions");
-                                       }
-                                       else
+                                       if (sessionfree)
                                        {
                                                uint16_t r;
-                                               controlt *c;
 
                                                s = sessionfree;
                                                sessionfree = session[s].next;
@@ -1907,31 +2340,40 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
                                                        config->cluster_highest_sessionid = s;
 
                                                // make a RADIUS session
-                                               if (!(r = radiusnew(s)))
+                                               if ((r = radiusnew(s)))
                                                {
-                                                       LOG(1, s, t, "No free RADIUS sessions for ICRQ\n");
-                                                       sessionkill(s, "no free RADIUS sesions");
-                                                       return;
+                                                       controlt *c = controlnew(11); // sending ICRP
+                                                       session[s].opened = time_now;
+                                                       session[s].tunnel = t;
+                                                       session[s].far = asession;
+                                                       session[s].last_packet = time_now;
+                                                       LOG(3, s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
+                                                       control16(c, 14, s, 1); // assigned session
+                                                       controladd(c, t, asession); // send the reply
+
+                                                       strncpy(radius[r].calling, calling, sizeof(radius[r].calling) - 1);
+                                                       strncpy(session[s].called, called, sizeof(session[s].called) - 1);
+                                                       strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
+                                                       STAT(session_created);
+                                                       break;
                                                }
 
-                                               c = controlnew(11); // sending ICRP
-                                               session[s].id = sessionid++;
-                                               session[s].opened = time(NULL);
-                                               session[s].tunnel = t;
-                                               session[s].far = asession;
-                                               session[s].last_packet = time_now;
-                                               LOG(3, s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
-                                               control16(c, 14, s, 1); // assigned session
-                                               controladd(c, t, s); // send the reply
-
-                                               // Generate a random challenge
-                                               random_data(radius[r].auth, sizeof(radius[r].auth));
-                                               strncpy(radius[r].calling, calling, sizeof(radius[r].calling) - 1);
-                                               strncpy(session[s].called, called, sizeof(session[s].called) - 1);
-                                               strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
-                                               STAT(session_created);
+
+                                               LOG(1, s, t, "No free RADIUS sessions for ICRQ\n");
+                                               sessionclear(s);
                                        }
-                                       break;
+                                       else
+                                       {
+                                               STAT(session_overflow);
+                                               LOG(1, 0, t, "No free sessions\n");
+                                       }
+
+                                       {
+                                               controlt *c = controlnew(14); // CDN
+                                               control16(c, 1, 4, 1); // temporary lack of resources
+                                               controladd(c, session[s].tunnel, asession); // send the message
+                                       }
+                                       return;
                                case 11:      // ICRP
                                        // TBA
                                        break;
@@ -1941,21 +2383,24 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
                                        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)
-                                               initlcp(t, s);
+                                       // proxy authentication type is not supported
+                                       if (!(config->radius_authtypes & authtype))
+                                               authtype = config->radius_authprefer;
+
+                                       // start LCP
+                                       sendlcp(t, s, authtype);
                                        break;
                                case 14:      // CDN
                                        controlnull(t); // ack
-                                       sessionshutdown(s, "Closed (Received CDN)");
+                                       sessionshutdown(s, "Closed (Received CDN).", 0, 0);
                                        break;
                                case 0xFFFF:
                                        LOG(1, s, t, "Missing message type\n");
                                        break;
                                default:
                                        STAT(tunnel_rx_errors);
-                                       if (mandatorymessage & 0x80)
-                                               tunnelshutdown(t, "Unknown message");
+                                       if (mandatory)
+                                               tunnelshutdown(t, "Unknown message type", 2, 6, "unknown message type");
                                        else
                                                LOG(1, s, t, "Unknown message type %d\n", message);
                                        break;
@@ -1996,7 +2441,7 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
                        l -= 2;
                }
 
-               if (s && !session[s].tunnel)    // Is something wrong??
+               if (s && !session[s].opened)    // Is something wrong??
                {
                        if (!config->cluster_iam_master)
                        {
@@ -2006,9 +2451,7 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
                        }
 
 
-                       LOG(1, s, t, "UDP packet contains session %d but no session[%d].tunnel "
-                                    "exists (LAC said tunnel = %d).  Dropping packet.\n", s, s, t);
-
+                       LOG(1, s, t, "UDP packet contains session which is not opened.  Dropping packet.\n");
                        STAT(tunnel_rx_errors);
                        return;
                }
@@ -2037,6 +2480,19 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
                        if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
                        processipcp(t, s, p, l);
                }
+               else if (prot == PPPIPV6CP)
+               {
+                       if (config->ipv6_prefix.s6_addr[0] > 0)
+                       {
+                               session[s].last_packet = time_now;
+                               if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
+                               processipv6cp(t, s, p, l);
+                       }
+                       else
+                       {
+                               LOG(1, s, t, "IPv6 not configured; ignoring IPv6CP\n");
+                       }
+               }
                else if (prot == PPPCCP)
                {
                        session[s].last_packet = time_now;
@@ -2060,6 +2516,28 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
 
                        processipin(t, s, p, l);
                }
+               else if (prot == PPPIPV6)
+               {
+                       if (!config->ipv6_prefix.s6_addr[0] > 0)
+                       {
+                               LOG(1, s, t, "IPv6 not configured; yet received IPv6 packet. Ignoring.\n");
+                               return;
+                       }
+                       if (session[s].die)
+                       {
+                               LOG(4, s, t, "Session %d is closing.  Don't process PPP packets\n", s);
+                               return;              // closing session, PPP not processed
+                       }
+
+                       session[s].last_packet = time_now;
+                       if (session[s].walled_garden && !config->cluster_iam_master)
+                       {
+                               master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
+                               return;
+                       }
+
+                       processipv6in(t, s, p, l);
+               }
                else
                {
                        STAT(tunnel_rx_errors);
@@ -2088,45 +2566,68 @@ static void processtun(uint8_t * buf, int len)
 
        if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IPv4
                processipout(buf, len);
+       else if (*(uint16_t *) (buf + 2) == htons(PKTIPV6) // IPV6
+           && config->ipv6_prefix.s6_addr[0] > 0)
+               processipv6out(buf, len);
+
        // Else discard.
 }
 
-//
-// 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)
+// Handle retries, timeouts.  Runs every 1/10th sec, want to ensure
+// that we look at the whole of the tunnel, radius and session tables
+// every second
+static void regular_cleanups(double period)
 {
-       static sessionidt s = 0;        // Next session to check for actions on.
-       tunnelidt t;
-       int count=0,i;
-       uint16_t r;
-       static clockt next_acct = 0;
-       static clockt next_shut_acct = 0;
+       // Next tunnel, radius and session to check for actions on.
+       static tunnelidt t = 0;
+       static int r = 0;
+       static sessionidt s = 0;
+
+       int t_actions = 0;
+       int r_actions = 0;
+       int s_actions = 0;
+
+       int t_slice;
+       int r_slice;
+       int s_slice;
+
+       int i;
        int a;
 
-       LOG(3, 0, 0, "Begin regular cleanup\n");
+       // divide up tables into slices based on the last run
+       t_slice = config->cluster_highest_tunnelid  * period;
+       r_slice = (MAXRADIUS - 1)                   * period;
+       s_slice = config->cluster_highest_sessionid * period;
 
-       for (r = 1; r < MAXRADIUS; r++)
-       {
-               if (!radius[r].state)
-                       continue;
-               if (radius[r].retry)
-               {
-                       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++)
+       if (t_slice < 1)
+           t_slice = 1;
+       else if (t_slice > config->cluster_highest_tunnelid)
+           t_slice = config->cluster_highest_tunnelid;
+
+       if (r_slice < 1)
+           r_slice = 1;
+       else if (r_slice > (MAXRADIUS - 1))
+           r_slice = MAXRADIUS - 1;
+
+       if (s_slice < 1)
+           s_slice = 1;
+       else if (s_slice > config->cluster_highest_sessionid)
+           s_slice = config->cluster_highest_sessionid;
+
+       LOG(4, 0, 0, "Begin regular cleanup (last %f seconds ago)\n", period);
+
+       for (i = 0; i < t_slice; i++)
        {
+               t++;
+               if (t > config->cluster_highest_tunnelid)
+                       t = 1;
+
                // check for expired tunnels
                if (tunnel[t].die && tunnel[t].die <= TIME)
                {
                        STAT(tunnel_timeout);
                        tunnelkill(t, "Expired");
+                       t_actions++;
                        continue;
                }
                // check for message resend
@@ -2146,6 +2647,8 @@ static int regular_cleanups(void)
                                                tunnelsend(c->buf, c->length, t);
                                                c = c->next;
                                        }
+
+                               t_actions++;
                        }
                }
                // Send hello
@@ -2154,6 +2657,7 @@ static int regular_cleanups(void)
                        controlt *c = controlnew(6); // sending HELLO
                        controladd(c, t, 0); // send the message
                        LOG(3, 0, t, "Sending HELLO message\n");
+                       t_actions++;
                }
 
                // Check for tunnel changes requested from the CLI
@@ -2163,47 +2667,66 @@ static int regular_cleanups(void)
                        if (a & CLI_TUN_KILL)
                        {
                                LOG(2, 0, t, "Dropping tunnel by CLI\n");
-                               tunnelshutdown(t, "Requested by administrator");
+                               tunnelshutdown(t, "Requested by administrator", 1, 0, 0);
+                               t_actions++;
                        }
                }
+       }
+
+       for (i = 0; i < r_slice; i++)
+       {
+               r++;
+               if (r >= MAXRADIUS)
+                       r = 1;
+
+               if (!radius[r].state)
+                       continue;
 
+               if (radius[r].retry <= TIME)
+               {
+                       radiusretry(r);
+                       r_actions++;
+               }
        }
 
-       count = 0;
-       for (i = 1; i <= config->cluster_highest_sessionid; i++)
+       for (i = 0; i < s_slice; i++)
        {
                s++;
                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))
+               // check for expired sessions
+               if (session[s].die)
                {
-                       // 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);
+                       if (session[s].die <= TIME)
+                       {
+                               sessionkill(s, "Expired");
+                               s_actions++;
+                       }
+                       continue;
                }
 
-               // check for expired sessions
-               if (session[s].die && session[s].die <= TIME)
+               if (session[s].ip && !(session[s].flags & SF_IPCP_ACKED))
                {
-                       sessionkill(s, "Expired");
-                       if (++count >= MAX_ACTIONS) break;
-                       continue;
+                       // 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);
+                       s_actions++;
                }
 
                // Drop sessions who have not responded within IDLE_TIMEOUT seconds
                if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
                {
-                       sessionshutdown(s, "No response to LCP ECHO requests");
+                       sessionshutdown(s, "No response to LCP ECHO requests.", 3, 0);
                        STAT(session_timeout);
-                       if (++count >= MAX_ACTIONS) break;
+                       s_actions++;
                        continue;
                }
 
-               // No data in IDLE_TIMEOUT seconds, send LCP ECHO
+               // No data in ECHO_TIMEOUT seconds, send LCP ECHO
                if (session[s].user[0] && (time_now - session[s].last_packet >= ECHO_TIMEOUT))
                {
                        uint8_t b[MAXCONTROL] = {0};
@@ -2219,7 +2742,7 @@ static int regular_cleanups(void)
                        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;
+                       s_actions++;
                }
 
                // Check for actions requested from the CLI
@@ -2231,8 +2754,9 @@ static int regular_cleanups(void)
                        if (a & CLI_SESS_KILL)
                        {
                                LOG(2, s, session[s].tunnel, "Dropping session by CLI\n");
-                               sessionshutdown(s, "Requested by administrator");
+                               sessionshutdown(s, "Requested by administrator.", 3, 0);
                                a = 0; // dead, no need to check for other actions
+                               s_actions++;
                        }
 
                        if (a & CLI_SESS_NOSNOOP)
@@ -2240,6 +2764,7 @@ static int regular_cleanups(void)
                                LOG(2, s, session[s].tunnel, "Unsnooping session by CLI\n");
                                session[s].snoop_ip = 0;
                                session[s].snoop_port = 0;
+                               s_actions++;
                                send++;
                        }
                        else if (a & CLI_SESS_SNOOP)
@@ -2250,6 +2775,7 @@ static int regular_cleanups(void)
 
                                session[s].snoop_ip = cli_session_actions[s].snoop_ip;
                                session[s].snoop_port = cli_session_actions[s].snoop_port;
+                               s_actions++;
                                send++;
                        }
 
@@ -2257,6 +2783,7 @@ static int regular_cleanups(void)
                        {
                                LOG(2, s, session[s].tunnel, "Un-throttling session by CLI\n");
                                throttle_session(s, 0, 0);
+                               s_actions++;
                                send++;
                        }
                        else if (a & CLI_SESS_THROTTLE)
@@ -2266,6 +2793,7 @@ static int regular_cleanups(void)
                                    cli_session_actions[s].throttle_out);
 
                                throttle_session(s, cli_session_actions[s].throttle_in, cli_session_actions[s].throttle_out);
+                               s_actions++;
                                send++;
                        }
 
@@ -2273,6 +2801,7 @@ static int regular_cleanups(void)
                        {
                                LOG(2, s, session[s].tunnel, "Un-filtering session by CLI\n");
                                filter_session(s, 0, 0);
+                               s_actions++;
                                send++;
                        }
                        else if (a & CLI_SESS_FILTER)
@@ -2282,42 +2811,40 @@ static int regular_cleanups(void)
                                    cli_session_actions[s].filter_out);
 
                                filter_session(s, cli_session_actions[s].filter_in, cli_session_actions[s].filter_out);
+                               s_actions++;
                                send++;
                        }
 
                        if (send)
                                cluster_send_session(s);
-
-                       if (++count >= MAX_ACTIONS) break;
                }
-       }
 
-       if (*config->accounting_dir)
-       {
-               if (next_acct <= TIME)
+               // RADIUS interim accounting
+               if (config->radius_accounting && config->radius_interim > 0
+                   && session[s].ip && !session[s].walled_garden
+                   && !sess_local[s].radius // RADIUS already in progress
+                   && time_now - sess_local[s].last_interim >= config->radius_interim)
                {
-                       // 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 (!(r = radiusnew(s)))
+                       {
+                               LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Interim message\n");
+                               STAT(radius_overflow);
+                               continue;
+                       }
+
+                       LOG(3, s, session[s].tunnel, "Sending RADIUS Interim for %s (%u)\n",
+                               session[s].user, session[s].unique_id);
+
+                       radiussend(r, RADIUSINTERIM);
+                       sess_local[s].last_interim = time_now;
+                       s_actions++;
                }
        }
 
-       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;
+       LOG(4, 0, 0, "End regular cleanup: checked %d/%d/%d tunnels/radius/sessions; %d/%d/%d actions\n",
+               t_slice, r_slice, s_slice, t_actions, r_actions, s_actions);
 }
 
-
 //
 // Are we in the middle of a tunnel update, or radius
 // requests??
@@ -2327,6 +2854,37 @@ static int still_busy(void)
        int i;
        static clockt last_talked = 0;
        static clockt start_busy_wait = 0;
+
+       if (!config->cluster_iam_master)
+       {
+#ifdef BGP
+               static time_t stopped_bgp = 0;
+               if (bgp_configured)
+               {
+                       if (!stopped_bgp)
+                       {
+                               LOG(1, 0, 0, "Shutting down in %d seconds, stopping BGP...\n", QUIT_DELAY);
+
+                               for (i = 0; i < BGP_NUM_PEERS; i++)
+                                       if (bgp_peers[i].state == Established)
+                                               bgp_stop(&bgp_peers[i]);
+
+                               stopped_bgp = time_now;
+
+                               // we don't want to become master
+                               cluster_send_ping(0);
+
+                               return 1;
+                       }
+
+                       if (time_now < (stopped_bgp + QUIT_DELAY))
+                               return 1;
+               }
+#endif /* BGP */
+
+               return 0;
+       }
+
        if (start_busy_wait == 0)
                start_busy_wait = TIME;
 
@@ -2368,80 +2926,104 @@ static int still_busy(void)
        return 0;
 }
 
-static fd_set readset;
-static int readset_n = 0;
+#ifdef HAVE_EPOLL
+# include <sys/epoll.h>
+#else
+# define FAKE_EPOLL_IMPLEMENTATION /* include the functions */
+# include "fake_epoll.h"
+#endif
+
+// the base set of fds polled: control, cli, udp, tun, cluster
+#define BASE_FDS       5
+
+// additional polled fds
+#ifdef BGP
+# define EXTRA_FDS     BGP_NUM_PEERS
+#else
+# define EXTRA_FDS     0
+#endif
 
 // main loop - gets packets on tun or udp and processes them
 static void mainloop(void)
 {
        int i;
        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;
+       struct epoll_event events[BASE_FDS + RADIUS_FDS + EXTRA_FDS];
+       int maxevent = sizeof(events)/sizeof(*events);
+
+       if ((epollfd = epoll_create(maxevent)) < 0)
+       {
+               LOG(0, 0, 0, "epoll_create failed: %s\n", strerror(errno));
+               exit(1);
+       }
 
        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())
+       /* setup our fds to poll for input */
        {
-               fd_set r;
-               int n = readset_n;
+               static struct event_data d[BASE_FDS];
+               struct epoll_event e;
+
+               e.events = EPOLLIN;
+               i = 0;
+
+               d[i].type = FD_TYPE_CONTROL;
+               e.data.ptr = &d[i++];
+               epoll_ctl(epollfd, EPOLL_CTL_ADD, controlfd, &e);
+
+               d[i].type = FD_TYPE_CLI;
+               e.data.ptr = &d[i++];
+               epoll_ctl(epollfd, EPOLL_CTL_ADD, clifd, &e);
+
+               d[i].type = FD_TYPE_UDP;
+               e.data.ptr = &d[i++];
+               epoll_ctl(epollfd, EPOLL_CTL_ADD, udpfd, &e);
+
+               d[i].type = FD_TYPE_TUN;
+               e.data.ptr = &d[i++];
+               epoll_ctl(epollfd, EPOLL_CTL_ADD, tunfd, &e);
+
+               d[i].type = FD_TYPE_CLUSTER;
+               e.data.ptr = &d[i++];
+               epoll_ctl(epollfd, EPOLL_CTL_ADD, cluster_sockfd, &e);
+       }
+
 #ifdef BGP
-               fd_set w;
-               int bgp_set[BGP_NUM_PEERS];
+       signal(SIGPIPE, SIG_IGN);
+       bgp_setup(config->as_number);
+       if (config->bind_address)
+               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 */
 
+       while (!main_quit || still_busy())
+       {
+               int more = 0;
+               int n;
+
                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);
+               bgp_set_poll();
 #endif /* BGP */
 
+               n = epoll_wait(epollfd, events, maxevent, 100); // timeout 100ms (1/10th sec)
                STAT(select_called);
 
-               TIME = now();
+               TIME = now(NULL);
                if (n < 0)
                {
                        if (errno == EINTR ||
@@ -2452,67 +3034,83 @@ static void mainloop(void)
                        main_quit++;
                        break;
                }
-               else if (n)
+
+               if (n)
                {
                        struct sockaddr_in addr;
                        int alen, c, s;
+                       int udp_ready = 0;
+                       int tun_ready = 0;
+                       int cluster_ready = 0;
                        int udp_pkts = 0;
                        int tun_pkts = 0;
                        int cluster_pkts = 0;
+#ifdef BGP
+                       uint32_t bgp_events[BGP_NUM_PEERS];
+                       memset(bgp_events, 0, sizeof(bgp_events));
+#endif /* BGP */
 
-                       // nsctl commands
-                       if (FD_ISSET(controlfd, &r))
+                       for (c = n, i = 0; i < c; i++)
                        {
-                               alen = sizeof(addr);
-                               processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
-                               n--;
-                       }
+                               struct event_data *d = events[i].data.ptr;
+                               switch (d->type)
+                               {
+                               case FD_TYPE_CONTROL: // nsctl commands
+                                       alen = sizeof(addr);
+                                       processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
+                                       n--;
+                                       break;
 
-                       // RADIUS responses
-                       if (config->cluster_iam_master)
-                       {
-                               for (i = 0; i < config->num_radfds; i++)
+                               case FD_TYPE_CLI: // CLI connections
                                {
-                                       if (FD_ISSET(radfds[i], &r))
+                                       int cli;
+                                       
+                                       alen = sizeof(addr);
+                                       if ((cli = accept(clifd, (struct sockaddr *)&addr, &alen)) >= 0)
                                        {
-                                               processrad(buf, recv(radfds[i], buf, sizeof(buf), 0), i);
-                                               n--;
+                                               cli_do(cli);
+                                               close(cli);
                                        }
-                               }
-                       }
+                                       else
+                                               LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
 
-                       // CLI connections
-                       if (FD_ISSET(clifd, &r))
-                       {
-                               int cli;
-                               
-                               alen = sizeof(addr);
-                               if ((cli = accept(clifd, (struct sockaddr *)&addr, &alen)) >= 0)
-                               {
-                                       cli_do(cli);
-                                       close(cli);
+                                       n--;
+                                       break;
                                }
-                               else
-                                       LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
 
-                               n--;
-                       }
+                               // these are handled below, with multiple interleaved reads
+                               case FD_TYPE_UDP:       udp_ready++; break;
+                               case FD_TYPE_TUN:       tun_ready++; break;
+                               case FD_TYPE_CLUSTER:   cluster_ready++; break;
+
+                               case FD_TYPE_RADIUS: // RADIUS response
+                                       s = recv(radfds[d->index], buf, sizeof(buf), 0);
+                                       if (s >= 0 && config->cluster_iam_master)
+                                               processrad(buf, s, d->index);
+
+                                       n--;
+                                       break;
 
 #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--;
+                               case FD_TYPE_BGP:
+                                       bgp_events[d->index] = events[i].events;
+                                       n--;
+                                       break;
+#endif /* BGP */
+
+                               default:
+                                       LOG(0, 0, 0, "Unexpected fd type returned from epoll_wait: %d\n", d->type);
+                               }
                        }
+
+#ifdef BGP
+                       bgp_process(bgp_events);
 #endif /* BGP */
 
                        for (c = 0; n && c < config->multi_read_count; c++)
                        {
                                // L2TP
-                               if (FD_ISSET(udpfd, &r))
+                               if (udp_ready)
                                {
                                        alen = sizeof(addr);
                                        if ((s = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
@@ -2522,13 +3120,13 @@ static void mainloop(void)
                                        }
                                        else
                                        {
-                                               FD_CLR(udpfd, &r);
+                                               udp_ready = 0;
                                                n--;
                                        }
                                }
 
                                // incoming IP
-                               if (FD_ISSET(tunfd, &r))
+                               if (tun_ready)
                                {
                                        if ((s = read(tunfd, buf, sizeof(buf))) > 0)
                                        {
@@ -2537,13 +3135,13 @@ static void mainloop(void)
                                        }
                                        else
                                        {
-                                               FD_CLR(tunfd, &r);
+                                               tun_ready = 0;
                                                n--;
                                        }
                                }
 
                                // cluster
-                               if (FD_ISSET(cluster_sockfd, &r))
+                               if (cluster_ready)
                                {
                                        alen = sizeof(addr);
                                        if ((s = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen)) > 0)
@@ -2553,7 +3151,7 @@ static void mainloop(void)
                                        }
                                        else
                                        {
-                                               FD_CLR(cluster_sockfd, &r);
+                                               cluster_ready = 0;
                                                n--;
                                        }
                                }
@@ -2568,11 +3166,12 @@ static void mainloop(void)
                                        config->multi_read_count, udp_pkts, tun_pkts, cluster_pkts);
 
                                STAT(multi_read_exceeded);
+                               more++;
                        }
                }
 
                        // Runs on every machine (master and slaves).
-               if (cluster_sockfd && next_cluster_ping <= TIME)
+               if (next_cluster_ping <= TIME)
                {
                        // Check to see which of the cluster is still alive..
 
@@ -2590,9 +3189,11 @@ static void mainloop(void)
                                next_cluster_ping = TIME + config->cluster_hb_interval;
                }
 
+               if (!config->cluster_iam_master)
+                       continue;
+
                        // 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)
@@ -2602,20 +3203,42 @@ static void mainloop(void)
                        }
                }
 
-               /* 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)
+                       // Handle timeouts, retries etc.
+               {
+                       static double last_clean = 0;
+                       double this_clean;
+                       double diff;
+
+                       TIME = now(&this_clean);
+                       diff = this_clean - last_clean;
+
+                       // Run during idle time (after we've handled
+                       // all incoming packets) or every 1/10th sec
+                       if (!more || diff > 0.1)
+                       {
+                               regular_cleanups(diff);
+                               last_clean = this_clean;
+                       }
+               }
+
+               if (*config->accounting_dir)
                {
-                       if (regular_cleanups())
+                       static clockt next_acct = 0;
+                       static clockt next_shut_acct = 0;
+
+                       if (next_acct <= TIME)
                        {
-                               // Did it finish?
-                               next_clean = time_now + 1 ;     // Didn't finish. Check quickly.
+                               // Dump accounting data
+                               next_acct = TIME + ACCT_TIME;
+                               next_shut_acct = TIME + ACCT_SHUT_TIME;
+                               dump_acct_info(1);
                        }
-                       else
+                       else if (next_shut_acct <= TIME)
                        {
-                               next_clean = time_now + config->cleanup_interval; // Did. Move to next interval.
+                               // Dump accounting data for shutdown sessions
+                               next_shut_acct = TIME + ACCT_SHUT_TIME;
+                               if (shut_acct_n)
+                                       dump_acct_info(0);
                        }
                }
        }
@@ -2630,6 +3253,7 @@ static void mainloop(void)
 
        //
        // Important!!! We MUST not process any packets past this point!
+       LOG(1, 0, 0, "Clean shutdown complete\n");
 }
 
 static void stripdomain(char *host)
@@ -2702,24 +3326,37 @@ 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));
+               fprintf(stderr, "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
+       config->cluster_master_min_adv = 1;
        strcpy(config->random_device, RANDOMDEVICE);
 
+       log_stream = stderr;
+
+#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 (!(_statistics = shared_malloc(sizeof(struct Tstats))))
+       {
+               LOG(0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno));
+               exit(1);
+       }
        if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)))
        {
                LOG(0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno));
@@ -2756,15 +3393,6 @@ static void initdata(int optdebug, char *optconfig)
        }
        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));
@@ -2785,7 +3413,7 @@ static void initdata(int optdebug, char *optconfig)
        memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
 
                // Put all the sessions on the free list marked as undefined.
-       for (i = 1; i < MAXSESSION - 1; i++)
+       for (i = 1; i < MAXSESSION; i++)
        {
                session[i].next = i + 1;
                session[i].tunnel = T_UNDEF;    // mark it as not filled in.
@@ -2794,7 +3422,7 @@ static void initdata(int optdebug, char *optconfig)
        sessionfree = 1;
 
                // Mark all the tunnels as undefined (waiting to be filled in by a download).
-       for (i = 1; i < MAXTUNNEL- 1; i++)
+       for (i = 1; i < MAXTUNNEL; i++)
                tunnel[i].state = TUNNELUNDEF;  // mark it as not filled in.
 
        if (!*hostname)
@@ -2920,8 +3548,9 @@ void rebuild_address_pool(void)
        for (i = 0; i < MAXSESSION; ++i)
        {
                int ipid;
-               if (!session[i].ip || !session[i].tunnel)
+               if (!(session[i].opened && session[i].ip))
                        continue;
+
                ipid = - lookup_ipmap(htonl(session[i].ip));
 
                if (session[i].ip_pool_index < 0)
@@ -3099,7 +3728,7 @@ void snoop_send_packet(char *packet, uint16_t size, in_addr_t destination, uint1
 
 static int dump_session(FILE **f, sessiont *s)
 {
-       if (!s->opened || !s->ip || !(s->cin || s->cout) || !*s->user || s->walled_garden)
+       if (!s->opened || !s->ip || !(s->cin_delta || s->cout_delta) || !*s->user || s->walled_garden)
                return 1;
 
        if (!*f)
@@ -3120,10 +3749,12 @@ static int dump_session(FILE **f, sessiont *s)
                LOG(3, 0, 0, "Dumping accounting information to %s\n", filename);
                fprintf(*f, "# dslwatch.pl dump file V1.01\n"
                        "# host: %s\n"
+                       "# endpoint: %s\n"
                        "# time: %ld\n"
                        "# uptime: %ld\n"
                        "# format: username ip qos uptxoctets downrxoctets\n",
                        hostname,
+                       fmtaddr(config->bind_address ? config->bind_address : my_address, 0),
                        now,
                        now - basetime);
        }
@@ -3133,11 +3764,10 @@ static int dump_session(FILE **f, sessiont *s)
                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
+               (uint32_t) s->cin_delta,                                // uptxoctets
+               (uint32_t) s->cout_delta);                              // downrxoctets
 
-       s->pin = s->cin = 0;
-       s->pout = s->cout = 0;
+       s->cin_delta = s->cout_delta = 0;
 
        return 1;
 }
@@ -3265,19 +3895,6 @@ int main(int argc, char *argv[])
        if (cluster_init() < 0)
                exit(1);
 
-#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 */
-
        inittun();
        LOG(1, 0, 0, "Set up on interface %s\n", config->tundevice);
 
@@ -3285,8 +3902,6 @@ int main(int argc, char *argv[])
        initrad();
        initippool();
 
-       read_state();
-
        signal(SIGHUP, sighup_handler);
        signal(SIGTERM, sigterm_handler);
        signal(SIGINT, sigterm_handler);
@@ -3310,14 +3925,6 @@ int main(int argc, char *argv[])
 
        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();
 
@@ -3333,9 +3940,11 @@ int main(int argc, char *argv[])
 
 static void sighup_handler(int sig)
 {
-       if (log_stream && log_stream != stderr)
+       if (log_stream)
        {
-               fclose(log_stream);
+               if (log_stream != stderr)
+                       fclose(log_stream);
+
                log_stream = NULL;
        }
 
@@ -3378,9 +3987,6 @@ static void sigalrm_handler(int sig)
 static void sigterm_handler(int sig)
 {
        LOG(1, 0, 0, "Shutting down cleanly\n");
-       if (config->save_state)
-               dump_state();
-
        main_quit++;
 }
 
@@ -3400,7 +4006,7 @@ static void sigquit_handler(int sig)
                for (i = 1; i < MAXTUNNEL; i++)
                {
                        if (tunnel[i].ip || tunnel[i].state)
-                               tunnelshutdown(i, "L2TPNS Closing");
+                               tunnelshutdown(i, "L2TPNS Closing", 6, 0, 0);
                }
        }
 
@@ -3413,182 +4019,6 @@ static void sigchild_handler(int sig)
            ;
 }
 
-static void read_state()
-{
-       struct stat sb;
-       int i;
-       ippoolt itmp;
-       FILE *f;
-       char magic[sizeof(DUMP_MAGIC) - 1];
-       uint32_t buf[2];
-
-       if (!config->save_state)
-       {
-               unlink(STATEFILE);
-               return ;
-       }
-
-       if (stat(STATEFILE, &sb) < 0)
-       {
-               unlink(STATEFILE);
-               return ;
-       }
-
-       if (sb.st_mtime < (time(NULL) - 60))
-       {
-               LOG(0, 0, 0, "State file is too old to read, ignoring\n");
-               unlink(STATEFILE);
-               return ;
-       }
-
-       f = fopen(STATEFILE, "r");
-       unlink(STATEFILE);
-
-       if (!f)
-       {
-               LOG(0, 0, 0, "Can't read state file: %s\n", strerror(errno));
-               exit(1);
-       }
-
-       if (fread(magic, sizeof(magic), 1, f) != 1 || strncmp(magic, DUMP_MAGIC, sizeof(magic)))
-       {
-               LOG(0, 0, 0, "Bad state file magic\n");
-               exit(1);
-       }
-
-       LOG(1, 0, 0, "Reading state information\n");
-       if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] > MAXIPPOOL || buf[1] != sizeof(ippoolt))
-       {
-               LOG(0, 0, 0, "Error/mismatch reading ip pool header from state file\n");
-               exit(1);
-       }
-
-       if (buf[0] > ip_pool_size)
-       {
-               LOG(0, 0, 0, "ip pool has shrunk!  state = %d, current = %d\n", buf[0], ip_pool_size);
-               exit(1);
-       }
-
-       LOG(2, 0, 0, "Loading %u ip addresses\n", buf[0]);
-       for (i = 0; i < buf[0]; i++)
-       {
-               if (fread(&itmp, sizeof(itmp), 1, f) != 1)
-               {
-                       LOG(0, 0, 0, "Error reading ip %d from state file: %s\n", i, strerror(errno));
-                       exit(1);
-               }
-
-               if (itmp.address != ip_address_pool[i].address)
-               {
-                       LOG(0, 0, 0, "Mismatched ip %d from state file: pool may only be extended\n", i);
-                       exit(1);
-               }
-
-               memcpy(&ip_address_pool[i], &itmp, sizeof(itmp));
-       }
-
-       if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] != MAXTUNNEL || buf[1] != sizeof(tunnelt))
-       {
-               LOG(0, 0, 0, "Error/mismatch reading tunnel header from state file\n");
-               exit(1);
-       }
-
-       LOG(2, 0, 0, "Loading %u tunnels\n", MAXTUNNEL);
-       if (fread(tunnel, sizeof(tunnelt), MAXTUNNEL, f) != MAXTUNNEL)
-       {
-               LOG(0, 0, 0, "Error reading tunnel data from state file\n");
-               exit(1);
-       }
-
-       for (i = 0; i < MAXTUNNEL; i++)
-       {
-               tunnel[i].controlc = 0;
-               tunnel[i].controls = NULL;
-               tunnel[i].controle = NULL;
-               if (*tunnel[i].hostname)
-                       LOG(3, 0, 0, "Created tunnel for %s\n", tunnel[i].hostname);
-       }
-
-       if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] != MAXSESSION || buf[1] != sizeof(sessiont))
-       {
-               LOG(0, 0, 0, "Error/mismatch reading session header from state file\n");
-               exit(1);
-       }
-
-       LOG(2, 0, 0, "Loading %u sessions\n", MAXSESSION);
-       if (fread(session, sizeof(sessiont), MAXSESSION, f) != MAXSESSION)
-       {
-               LOG(0, 0, 0, "Error reading session data from state file\n");
-               exit(1);
-       }
-
-       for (i = 0; i < MAXSESSION; i++)
-       {
-               session[i].tbf_in = 0;
-               session[i].tbf_out = 0;
-               if (session[i].opened)
-               {
-                       LOG(2, i, 0, "Loaded active session for user %s\n", session[i].user);
-                       if (session[i].ip)
-                               sessionsetup(session[i].tunnel, i);
-               }
-       }
-
-       fclose(f);
-       LOG(0, 0, 0, "Loaded saved state information\n");
-}
-
-static void dump_state()
-{
-       FILE *f;
-       uint32_t buf[2];
-
-       if (!config->save_state)
-               return;
-
-       do
-       {
-               if (!(f = fopen(STATEFILE, "w")))
-                       break;
-
-               LOG(1, 0, 0, "Dumping state information\n");
-
-               if (fwrite(DUMP_MAGIC, sizeof(DUMP_MAGIC) - 1, 1, f) != 1)
-                       break;
-
-               LOG(2, 0, 0, "Dumping %u ip addresses\n", ip_pool_size);
-               buf[0] = ip_pool_size;
-               buf[1] = sizeof(ippoolt);
-               if (fwrite(buf, sizeof(buf), 1, f) != 1)
-                       break;
-               if (fwrite(ip_address_pool, sizeof(ippoolt), ip_pool_size, f) != ip_pool_size)
-                       break;
-
-               LOG(2, 0, 0, "Dumping %u tunnels\n", MAXTUNNEL);
-               buf[0] = MAXTUNNEL;
-               buf[1] = sizeof(tunnelt);
-               if (fwrite(buf, sizeof(buf), 1, f) != 1)
-                       break;
-               if (fwrite(tunnel, sizeof(tunnelt), MAXTUNNEL, f) != MAXTUNNEL)
-                       break;
-
-               LOG(2, 0, 0, "Dumping %u sessions\n", MAXSESSION);
-               buf[0] = MAXSESSION;
-               buf[1] = sizeof(sessiont);
-               if (fwrite(buf, sizeof(buf), 1, f) != 1)
-                       break;
-               if (fwrite(session, sizeof(sessiont), MAXSESSION, f) != MAXSESSION)
-                       break;
-
-               if (fclose(f) == 0)
-                       return ; // OK
-       }
-       while (0);
-
-       LOG(0, 0, 0, "Can't write state information: %s\n", strerror(errno));
-       unlink(STATEFILE);
-}
-
 static void build_chap_response(char *challenge, uint8_t id, uint16_t challenge_length, char **challenge_response)
 {
        MD5_CTX ctx;
@@ -3636,7 +4066,9 @@ static void update_config()
        syslog_log = 0;
        if (log_stream)
        {
-               fclose(log_stream);
+               if (log_stream != stderr)
+                       fclose(log_stream);
+
                log_stream = NULL;
        }
 
@@ -3684,7 +4116,7 @@ static void update_config()
                        // 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])
+                       if (i > 0 && !config->radiusport[i])
                                config->radiusport[i] = config->radiusport[i-1];
                        if (!config->radiusport[i])
                                config->radiusport[i] = RADPORT;
@@ -3693,12 +4125,10 @@ static void update_config()
        if (!config->numradiusservers)
                LOG(0, 0, 0, "No RADIUS servers defined!\n");
 
-       config->num_radfds = 2 << RADIUS_SHIFT;
-
        // parse radius_authtypes_s
        config->radius_authtypes = config->radius_authprefer = 0;
        p = config->radius_authtypes_s;
-       while (*p)
+       while (p && *p)
        {
                char *s = strpbrk(p, " \t,");
                int type = 0;
@@ -3718,11 +4148,13 @@ static void update_config()
                else if (!strncasecmp("pap", p, strlen(p)))
                        type = AUTHPAP;
                else
-                       LOG(0, 0, 0, "Invalid RADIUS authentication type \"%s\"", p);
+                       LOG(0, 0, 0, "Invalid RADIUS authentication type \"%s\"\n", p);
 
                config->radius_authtypes |= type;
                if (!config->radius_authprefer)
                        config->radius_authprefer = type;
+
+               p = s;
        }
 
        if (!config->radius_authtypes)
@@ -3767,7 +4199,6 @@ static 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)
@@ -3848,13 +4279,13 @@ int sessionsetup(tunnelidt t, sessionidt s)
 
        LOG(3, s, t, "Doing session setup for session\n");
 
-       if (!session[s].ip || session[s].ip == 0xFFFFFFFE)
+       if (!session[s].ip)
        {
                assign_ip_address(s);
                if (!session[s].ip)
                {
                        LOG(0, s, t, "   No IP allocated.  The IP address pool is FULL!\n");
-                       sessionshutdown(s, "No IP addresses available");
+                       sessionshutdown(s, "No IP addresses available.", 2, 7);
                        return 0;
                }
                LOG(3, s, t, "   No IP allocated.  Assigned %s from pool\n",
@@ -3874,8 +4305,16 @@ int sessionsetup(tunnelidt t, sessionidt s)
                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)
+                       if (!session[s].opened) continue;
+                       if (ip == session[i].ip)
+                       {
+                               sessionkill(i, "Duplicate IP address");
+                               continue;
+                       }
+
+                       if (config->allow_duplicate_users) continue;
+                       if (session[s].walled_garden || session[i].walled_garden) continue;
+                       if (!strcasecmp(user, session[i].user))
                                sessionkill(i, "Duplicate session for users");
                }
        }
@@ -3897,6 +4336,7 @@ int sessionsetup(tunnelidt t, sessionidt s)
                // convered by a Framed-Route.  Anything else is part
                // of the IP address pool and is already routed, it
                // just needs to be added to the IP cache.
+               // IPv6 route setup is done in ppp.c, when IPV6CP is acked.
                if (session[s].ip_pool_index == -1) // static ip
                {
                        if (!routed) routeset(s, session[s].ip, 0, 0, 1);
@@ -4019,6 +4459,10 @@ int load_session(sessionidt s, sessiont *new)
                }
        }
 
+       // check v6 routing
+       if (new->flags & SF_IPV6_ROUTED && !(session[s].flags & SF_IPV6_ROUTED))
+                   route6set(s, new->ipv6route, new->ipv6prefixlen, 1);
+
        // check filters
        if (new->filter_in && (new->filter_in > MAXFILTER || !ip_filters[new->filter_in - 1].name[0]))
        {
@@ -4117,6 +4561,7 @@ static int add_plugin(char *plugin_name)
                radiusnew,
                radiussend,
                getconfig,
+               sessionshutdown,
                sessionkill,
                throttle_session,
                cluster_send_session,
@@ -4437,6 +4882,9 @@ static tunnelidt new_tunnel()
 void become_master(void)
 {
        int s, i;
+       static struct event_data d[RADIUS_FDS];
+       struct epoll_event e;
+
        run_plugins(PLUGIN_BECOME_MASTER, NULL);
 
        // running a bunch of iptables commands is slow and can cause
@@ -4446,7 +4894,7 @@ 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]);
@@ -4455,11 +4903,14 @@ void become_master(void)
        }
 
        // add radius fds
-       for (i = 0; i < config->num_radfds; i++)
+       e.events = EPOLLIN;
+       for (i = 0; i < RADIUS_FDS; i++)
        {
-               FD_SET(radfds[i], &readset);
-               if (radfds[i] > readset_n)
-                       readset_n = radfds[i];
+               d[i].type = FD_TYPE_RADIUS;
+               d[i].index = i;
+               e.data.ptr = &d[i];
+
+               epoll_ctl(epollfd, EPOLL_CTL_ADD, radfds[i], &e);
        }
 }
 
@@ -4478,7 +4929,7 @@ 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;
@@ -4516,7 +4967,7 @@ 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;
@@ -4543,75 +4994,45 @@ int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc
 
 /* Unhide an avp.
  *
- * This unencodes the AVP using the L2TP CHAP secret and the
- * previously stored random vector. It replaces the hidden data with
- * the cleartext data and returns the length of the cleartext data
- * (including the AVP "header" of 6 bytes).
- *
- * Based on code from rp-l2tpd by Roaring Penguin Software Inc.
+ * This unencodes the AVP using the L2TP secret and the previously
+ * stored random vector.  It overwrites the hidden data with the
+ * unhidden AVP subformat.
  */
-static int unhide_avp(uint8_t *avp, tunnelidt t, sessionidt s, uint16_t length)
+static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len)
 {
        MD5_CTX ctx;
-       uint8_t *cursor;
        uint8_t digest[16];
-       uint8_t working_vector[16];
-       uint16_t hidden_length;
-       uint8_t type[2];
-       size_t done, todo;
-       uint8_t *output;
-
-       // Find the AVP type.
-       type[0] = *(avp + 4);
-       type[1] = *(avp + 5);
-
-       // Line up with the hidden data
-       cursor = output = avp + 6;
+       uint8_t *last;
+       size_t d = 0;
 
        // Compute initial pad
        MD5Init(&ctx);
-       MD5Update(&ctx, type, 2);
+       MD5Update(&ctx, (uint8_t) (type >> 8) & 0xff, 1);
+       MD5Update(&ctx, (uint8_t)  type       & 0xff, 1);
        MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
-       MD5Update(&ctx, session[s].random_vector, session[s].random_vector_length);
+       MD5Update(&ctx, vector, vec_len);
        MD5Final(digest, &ctx);
 
-       // Get hidden length
-       hidden_length = ((uint16_t) (digest[0] ^ cursor[0])) * 256 + (uint16_t) (digest[1] ^ cursor[1]);
-
-       // Keep these for later use
-       working_vector[0] = *cursor;
-       working_vector[1] = *(cursor + 1);
-       cursor += 2;
+       // pointer to last decoded 16 octets
+       last = value;
 
-       if (hidden_length > length - 8)
+       while (len > 0)
        {
-               LOG(1, s, t, "Hidden length %d too long in AVP of length %d\n", (int) hidden_length, (int) length);
-               return 0;
-       }
-
-       /* Decrypt remainder */
-       done = 2;
-       todo = hidden_length;
-       while (todo)
-       {
-               working_vector[done] = *cursor;
-               *output = digest[done] ^ *cursor;
-               ++output;
-               ++cursor;
-               --todo;
-               ++done;
-               if (done == 16 && todo)
+               // calculate a new pad based on the last decoded block
+               if (d >= sizeof(digest))
                {
-                       // Compute new digest
-                       done = 0;
                        MD5Init(&ctx);
                        MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
-                       MD5Update(&ctx, &working_vector, 16);
+                       MD5Update(&ctx, last, sizeof(digest));
                        MD5Final(digest, &ctx);
+
+                       d = 0;
+                       last = value;
                }
-       }
 
-       return hidden_length + 6;
+               *value++ ^= digest[d++];
+               len--;
+       }
 }
 
 static int ip_filter_port(ip_filter_portt *p, uint16_t port)