remove non-working setuid option
[l2tpns.git] / l2tpns.c
index 2efbc05..3d789a5 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 1.75 2005-01-07 07:18:33 bodea Exp $";
+char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.164 2006-04-27 14:37:27 bodea Exp $";
 
 #include <arpa/inet.h>
 #include <assert.h>
@@ -19,6 +19,7 @@ char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.75 2005-01-07 07:18:33 bodea Exp
 #include <sys/mman.h>
 #include <netdb.h>
 #include <netinet/in.h>
+#include <netinet/ip6.h>
 #include <stdarg.h>
 #include <stdlib.h>
 #include <stdio.h>
@@ -51,7 +52,7 @@ char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.75 2005-01-07 07:18:33 bodea Exp
 
 #ifdef BGP
 #include "bgp.h"
-#endif /* BGP */
+#endif
 
 // Globals
 configt *config = NULL;                // all configuration
@@ -59,22 +60,33 @@ int tunfd = -1;                     // tun interface file handle. (network device)
 int udpfd = -1;                        // UDP file handle
 int controlfd = -1;            // Control signal handle
 int clifd = -1;                        // Socket listening for CLI connections.
+int daefd = -1;                        // Socket listening for DAE 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
+
+// calculated from config->l2tp_mtu
+uint16_t MRU = 0;              // PPP MRU
+uint16_t MSS = 0;              // TCP MSS
 
 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 +96,9 @@ 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.
+static int time_changed = 0;           // time_now changed
+char main_quit = 0;                    // True if we're in the process of exiting.
+static char main_reload = 0;           // Re-load pending
 linked_list *loaded_plugins;
 linked_list *plugins[MAX_PLUGIN_TYPES];
 
@@ -96,34 +110,43 @@ config_descriptt config_values[] = {
        CONFIG("log_file", log_filename, STRING),
        CONFIG("pid_file", pid_file, STRING),
        CONFIG("random_device", random_device, STRING),
-       CONFIG("l2tp_secret", l2tpsecret, STRING),
+       CONFIG("l2tp_secret", l2tp_secret, STRING),
+       CONFIG("l2tp_mtu", l2tp_mtu, INT),
+       CONFIG("ppp_restart_time", ppp_restart_time, INT),
+       CONFIG("ppp_max_configure", ppp_max_configure, INT),
+       CONFIG("ppp_max_failure", ppp_max_failure, INT),
        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("radius_dae_port", radius_dae_port, SHORT),
+       CONFIG("allow_duplicate_users", allow_duplicate_users, BOOL),
+       CONFIG("guest_account", guest_user, STRING),
        CONFIG("bind_address", bind_address, IPv4),
        CONFIG("peer_address", peer_address, IPv4),
        CONFIG("send_garp", send_garp, BOOL),
        CONFIG("throttle_speed", rl_rate, UNSIGNED_LONG),
        CONFIG("throttle_buckets", num_tbfs, INT),
        CONFIG("accounting_dir", accounting_dir, STRING),
-       CONFIG("setuid", target_uid, INT),
        CONFIG("dump_speed", dump_speed, BOOL),
-       CONFIG("cleanup_interval", cleanup_interval, INT),
        CONFIG("multi_read_count", multi_read_count, INT),
        CONFIG("scheduler_fifo", scheduler_fifo, BOOL),
        CONFIG("lock_pages", lock_pages, BOOL),
        CONFIG("icmp_rate", icmp_rate, INT),
+       CONFIG("packet_limit", max_packets, INT),
        CONFIG("cluster_address", cluster_address, IPv4),
        CONFIG("cluster_interface", cluster_interface, STRING),
+       CONFIG("cluster_mcast_ttl", cluster_mcast_ttl, INT),
        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 },
 };
 
@@ -138,6 +161,8 @@ static char *plugin_functions[] = {
        "plugin_kill_session",
        "plugin_control",
        "plugin_radius_response",
+       "plugin_radius_reset",
+       "plugin_radius_account",
        "plugin_become_master",
        "plugin_new_session_master",
 };
@@ -149,11 +174,13 @@ static sessiont shut_acct[8192];
 static sessionidt shut_acct_n = 0;
 
 tunnelt *tunnel = NULL;                        // Array of tunnel structures.
+bundlet *bundle = NULL;                        // Array of bundle structures.
+fragmentationt *frag = NULL;           // Array of fragmentation structures.
 sessiont *session = NULL;              // Array of session structures.
-sessioncountt *sess_count = NULL;      // Array of partial per-session traffic counters.
+sessionlocalt *sess_local = NULL;      // Array of local per-session counters.
 radiust *radius = NULL;                        // Array of radius structures.
 ippoolt *ip_address_pool = NULL;       // Array of dynamic IP addresses.
-ip_filtert *ip_filters = NULL; // Array of named filters.
+ip_filtert *ip_filters = NULL;         // Array of named filters.
 static controlt *controlfree = 0;
 struct Tstats *_statistics = NULL;
 #ifdef RINGBUFFER
@@ -162,31 +189,43 @@ 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);
-static void sigalrm_handler(int sig);
-static void sigterm_handler(int sig);
-static void sigquit_handler(int sig);
+static void shutdown_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 build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response);
 static void update_config(void);
 static void read_config_file(void);
 static void initplugins(void);
 static int add_plugin(char *plugin_name);
 static int remove_plugin(char *plugin_name);
 static void plugins_done(void);
-static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen);
+static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen, struct in_addr *local);
 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);
+static void bundleclear(bundleidt b);
+
+// on slaves, alow BGP to withdraw cleanly before exiting
+#define QUIT_DELAY     5
 
-// return internal time (10ths since process startup)
-static clockt now(void)
+// quit actions (master)
+#define QUIT_FAILOVER  1 // SIGTERM: exit when all control messages have been acked (for cluster failover)
+#define QUIT_SHUTDOWN  2 // SIGQUIT: shutdown sessions/tunnels, reject new connections
+
+// return internal time (10ths since process startup), set f if given
+// as a side-effect sets time_now, and time_changed
+static clockt now(double *f)
 {
        struct timeval t;
        gettimeofday(&t, 0);
+       if (f) *f = t.tv_sec + t.tv_usec / 1000000.0;
+       if (t.tv_sec != time_now)
+       {
+           time_now = t.tv_sec;
+           time_changed++;
+       }
        return (t.tv_sec - basetime) * 10 + t.tv_usec / 100000 + 1;
 }
 
@@ -196,7 +235,7 @@ 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);
 }
 
 
@@ -239,10 +278,10 @@ void _log(int level, sessionidt s, tunnelidt t, const char *format, ...)
        va_end(ap);
 }
 
-void _log_hex(int level, const char *title, const char *data, int maxsize)
+void _log_hex(int level, const char *title, const uint8_t *data, int maxsize)
 {
        int i, j;
-       const uint8_t *d = (const uint8_t *) data;
+       const uint8_t *d = data;
 
        if (config->debug < level) return;
 
@@ -290,6 +329,16 @@ 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)
 {
@@ -300,7 +349,8 @@ static void initrandom(char *source)
                return;
 
        // close previous source, if any
-       if (rand_fd >= 0) close(rand_fd);
+       if (rand_fd >= 0)
+               close(rand_fd);
 
        rand_fd = -1;
 
@@ -317,13 +367,6 @@ static void initrandom(char *source)
                                        path, strerror(errno));
                }
        }
-
-       // no source: seed prng
-       {
-               unsigned seed = time_now ^ getpid();
-               LOG(4, 0, 0, "Seeding the pseudo random generator: %u\n", seed);
-               srand(seed);
-       }
 }
 
 // fill buffer with random data
@@ -344,7 +387,7 @@ void random_data(uint8_t *buf, int len)
                                        strerror(errno));
 
                                // fall back to rand()
-                               initrandom(0);
+                               initrandom(NULL);
                        }
 
                        n = 0;
@@ -420,11 +463,61 @@ 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;
@@ -464,15 +557,58 @@ static void inittun(void)
                LOG(0, 0, 0, "Error setting tun queue length: %s\n", strerror(errno));
                exit(1);
        }
+       /* set MTU to modem MRU */
+       ifr.ifr_mtu = MRU;
+       if (ioctl(ifrfd, SIOCSIFMTU, (void *) &ifr) < 0)
+       {
+               LOG(0, 0, 0, "Error setting tun MTU: %s\n", strerror(errno));
+               exit(1);
+       }
        ifr.ifr_flags = IFF_UP;
        if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0)
        {
                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]) {
+               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
+// set up UDP ports
 static void initudp(void)
 {
        int on = 1;
@@ -494,7 +630,6 @@ static void initudp(void)
                LOG(0, 0, 0, "Error in UDP bind: %s\n", strerror(errno));
                exit(1);
        }
-       snoopfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
 
        // Control
        memset(&addr, 0, sizeof(addr));
@@ -502,11 +637,28 @@ static void initudp(void)
        addr.sin_port = htons(NSCTL_PORT);
        controlfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
        setsockopt(controlfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
+       setsockopt(controlfd, SOL_IP, IP_PKTINFO, &on, sizeof(on)); // recvfromto
        if (bind(controlfd, (void *) &addr, sizeof(addr)) < 0)
        {
                LOG(0, 0, 0, "Error in control bind: %s\n", strerror(errno));
                exit(1);
        }
+
+       // Dynamic Authorization Extensions to RADIUS
+       memset(&addr, 0, sizeof(addr));
+       addr.sin_family = AF_INET;
+       addr.sin_port = htons(config->radius_dae_port);
+       daefd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
+       setsockopt(daefd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
+       setsockopt(daefd, SOL_IP, IP_PKTINFO, &on, sizeof(on)); // recvfromto
+       if (bind(daefd, (void *) &addr, sizeof(addr)) < 0)
+       {
+               LOG(0, 0, 0, "Error in DAE bind: %s\n", strerror(errno));
+               exit(1);
+       }
+
+       // Intercept
+       snoopfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
 }
 
 //
@@ -536,17 +688,65 @@ 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] == 0 &&
+                ip.s6_addr16[2] == 0 &&
+                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.
@@ -586,6 +786,42 @@ 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.
 //
@@ -641,8 +877,11 @@ 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.
 
@@ -684,17 +923,16 @@ 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;
 }
 
@@ -707,18 +945,14 @@ void tunnelsend(uint8_t * buf, uint16_t l, tunnelidt t)
 
        if (!t)
        {
-               static int backtrace_count = 0;
                LOG(0, 0, t, "tunnelsend called with 0 as tunnel id\n");
                STAT(tunnel_tx_errors);
-               log_backtrace(backtrace_count, 5)
                return;
        }
 
        if (!tunnel[t].ip)
        {
-               static int backtrace_count = 0;
                LOG(1, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
-               log_backtrace(backtrace_count, 5)
                STAT(tunnel_tx_errors);
                return;
        }
@@ -736,7 +970,7 @@ void tunnelsend(uint8_t * buf, uint16_t l, tunnelidt t)
        {
                tunnel[t].last = time_now; // control message sent
                tunnel[t].retry = backoff(tunnel[t].try); // when to resend
-               if (tunnel[t].try > 1)
+               if (tunnel[t].try)
                {
                        STAT(tunnel_retries);
                        LOG(3, 0, t, "Control message resend try %d\n", tunnel[t].try);
@@ -765,32 +999,136 @@ int tun_write(uint8_t * data, int size)
        return write(tunfd, data, size);
 }
 
+// adjust tcp mss to avoid fragmentation (called only for tcp packets with syn set)
+void adjust_tcp_mss(sessionidt s, tunnelidt t, uint8_t *buf, int len, uint8_t *tcp)
+{
+       int d = (tcp[12] >> 4) * 4;
+       uint8_t *mss = 0;
+       uint8_t *opts;
+       uint8_t *data;
+       uint16_t orig;
+       uint32_t sum;
+
+       if ((tcp[13] & 0x3f) & ~(TCP_FLAG_SYN|TCP_FLAG_ACK)) // only want SYN and SYN,ACK
+               return;
+
+       if (tcp + d > buf + len) // short?
+               return;
+
+       opts = tcp + 20;
+       data = tcp + d;
+
+       while (opts < data)
+       {
+               if (*opts == 2 && opts[1] == 4) // mss option (2), length 4
+               {
+                       mss = opts + 2;
+                       if (mss + 2 > data) return; // short?
+                       break;
+               }
+
+               if (*opts == 0) return; // end of options
+               if (*opts == 1 || !opts[1]) // no op (one byte), or no length (prevent loop)
+                       opts++;
+               else
+                       opts += opts[1]; // skip over option
+       }
+
+       if (!mss) return; // not found
+       orig = ntohs(*(uint16_t *) mss);
+
+       if (orig <= MSS) return; // mss OK
+
+       LOG(5, s, t, "TCP: %s:%u -> %s:%u SYN%s: adjusted mss from %u to %u\n",
+               fmtaddr(*(in_addr_t *) (buf + 12), 0), ntohs(*(uint16_t *) tcp),
+               fmtaddr(*(in_addr_t *) (buf + 16), 1), ntohs(*(uint16_t *) (tcp + 2)),
+               (tcp[13] & TCP_FLAG_ACK) ? ",ACK" : "", orig, MSS);
+
+       // set mss
+       *(int16_t *) mss = htons(MSS);
+
+       // adjust checksum (see rfc1141)
+       sum = orig + (~MSS & 0xffff);
+       sum += ntohs(*(uint16_t *) (tcp + 16));
+       sum = (sum & 0xffff) + (sum >> 16);
+       *(uint16_t *) (tcp + 16) = htons(sum + (sum >> 16));
+}
+
+void processmpframe(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l, uint8_t extra)
+{
+       uint16_t proto;
+       if (extra) {
+               // Skip the four extra bytes
+               p += 4;
+               l -= 4;
+       }
+
+       // Process this frame
+       if (*p & 1)
+       {
+               proto = *p++;
+               l--;
+       }
+       else
+       {
+               proto = ntohs(*(uint16_t *) p);
+               p += 2;
+               l -= 2;
+       }
+       if (proto == PPPIP)
+       {
+               if (session[s].die)
+               {
+                       LOG(4, s, t, "MPPP: Session %d is closing.  Don't process PPP packets\n", s);
+                       return;              // closing session, PPP not processed
+               }
+               session[s].last_packet = time_now;
+               processipin(s, t, p, l);
+       }
+       else if (proto == PPPIPV6 && config->ipv6_prefix.s6_addr[0])
+       {
+               if (session[s].die)
+               {
+                       LOG(4, s, t, "MPPP: Session %d is closing.  Don't process PPP packets\n", s);
+                       return;              // closing session, PPP not processed
+               }
+
+               session[s].last_packet = time_now;
+               processipv6in(s, t, p, l);
+       }
+       else
+       {
+               LOG(2, s, t, "MPPP: Unsupported MP protocol 0x%04X received\n",proto);
+       }
+}
+
 // process outgoing (to tunnel) IP
 //
-static void processipout(uint8_t * buf, int len)
+static void processipout(uint8_t *buf, int len)
 {
        sessionidt s;
        sessiont *sp;
        tunnelidt t;
        in_addr_t ip;
 
-       char * data = buf;      // Keep a copy of the originals.
+       uint8_t *data = buf;    // Keep a copy of the originals.
        int size = len;
 
-       uint8_t b[MAXETHER + 20];
+       uint8_t b1[MAXETHER + 20];
+       uint8_t b2[MAXETHER + 20];
 
        CSTAT(processipout);
 
        if (len < MIN_IP_SIZE)
        {
                LOG(1, 0, 0, "Short IP, %d bytes\n", len);
-               STAT(tunnel_tx_errors);
+               STAT(tun_rx_errors);
                return;
        }
        if (len >= MAXETHER)
        {
                LOG(1, 0, 0, "Oversize IP packet %d bytes\n", len);
-               STAT(tunnel_tx_errors);
+               STAT(tun_rx_errors);
                return;
        }
 
@@ -821,17 +1159,65 @@ 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;
        }
        t = session[s].tunnel;
        sp = &session[s];
 
+       // DoS prevention: enforce a maximum number of packets per 0.1s for a session
+       if (config->max_packets > 0)
+       {
+               if (sess_local[s].last_packet_out == TIME)
+               {
+                       int max = config->max_packets;
+
+                       // All packets for throttled sessions are handled by the
+                       // master, so further limit by using the throttle rate.
+                       // A bit of a kludge, since throttle rate is in kbps,
+                       // but should still be generous given our average DSL
+                       // packet size is 200 bytes: a limit of 28kbps equates
+                       // to around 180 packets per second.
+                       if (!config->cluster_iam_master && sp->throttle_out && sp->throttle_out < max)
+                               max = sp->throttle_out;
+
+                       if (++sess_local[s].packets_out > max)
+                       {
+                               sess_local[s].packets_dropped++;
+                               return;
+                       }
+               }
+               else
+               {
+                       if (sess_local[s].packets_dropped)
+                       {
+                               INC_STAT(tun_rx_dropped, sess_local[s].packets_dropped);
+                               LOG(3, s, t, "Dropped %u/%u packets to %s for %suser %s\n",
+                                       sess_local[s].packets_dropped, sess_local[s].packets_out,
+                                       fmtaddr(ip, 0), sp->throttle_out ? "throttled " : "",
+                                       sp->user);
+                       }
+
+                       sess_local[s].last_packet_out = TIME;
+                       sess_local[s].packets_out = 1;
+                       sess_local[s].packets_dropped = 0;
+               }
+       }
+
        // run access-list if any
        if (session[s].filter_out && !ip_filter(buf, len, session[s].filter_out - 1))
                return;
 
+       // adjust MSS on SYN and SYN,ACK packets with options
+       if ((ntohs(*(uint16_t *) (buf + 6)) & 0x1fff) == 0 && buf[9] == IPPROTO_TCP) // first tcp fragment
+       {
+               int ihl = (buf[0] & 0xf) * 4; // length of IP header
+               if (len >= ihl + 20 && (buf[ihl + 13] & TCP_FLAG_SYN) && ((buf[ihl + 12] >> 4) > 5))
+                       adjust_tcp_mss(s, t, buf, len, buf + ihl);
+       }
+
        if (sp->tbf_out)
        {
                // Are we throttling this session?
@@ -841,48 +1227,93 @@ static void processipout(uint8_t * buf, int len)
                        master_throttle_packet(sp->tbf_out, data, size);
                return;
        }
-       else if (sp->walled_garden && !config->cluster_iam_master)
+
+       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, PPPIP);
-               if (!p) return;
-               tunnelsend(b, len + (p-b), t); // send it...
+               bundleidt bid = 0;
+               if (session[s].bundle && bundle[session[s].bundle].num_of_links > 1)
+               {
+                       bid = session[s].bundle;
+                       s = bundle[bid].members[bundle[bid].current_ses = ++bundle[bid].current_ses % bundle[bid].num_of_links];
+                       LOG(4, s, t, "MPPP: (1)Session number becomes: %d\n", s);
+                       if (len > 256)
+                       {
+                               // Partition the packet to 2 fragments
+                               uint32_t frag1len = len / 2;
+                               uint32_t frag2len = len - frag1len;
+                               uint8_t *p = makeppp(b1, sizeof(b1), buf, frag1len, s, t, PPPIP, 0, bid, MP_BEGIN);
+                               uint8_t *q;
+
+                               if (!p) return;
+                               tunnelsend(b1, frag1len + (p-b1), t); // send it...
+                               s = bundle[bid].members[bundle[bid].current_ses = ++bundle[bid].current_ses % bundle[bid].num_of_links];
+                               LOG(4, s, t, "MPPP: (2)Session number becomes: %d\n", s);
+                               q = makeppp(b2, sizeof(b2), buf+frag1len, frag2len, s, t, PPPIP, 0, bid, MP_END);
+                               if (!q) return;
+                               tunnelsend(b2, frag2len + (q-b2), t); // send it...
+                       }
+                       else {
+                               // Send it as one frame
+                               uint8_t *p = makeppp(b1, sizeof(b1), buf, len, s, t, PPPIP, 0, bid, MP_BOTH_BITS);
+                               if (!p) return;
+                               tunnelsend(b1, len + (p-b1), t); // send it...
+                       }
+               }
+               else
+               {
+                       uint8_t *p = makeppp(b1, sizeof(b1), buf, len, s, t, PPPIP, 0, 0, 0);
+                       if (!p) return;
+                       tunnelsend(b1, len + (p-b1), t); // send it...
+               }
        }
 
        // Snooping this session, send it to intercept box
        if (sp->snoop_ip && sp->snoop_port)
                snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
 
-       sp->cout += len; // byte count
-       sp->total_cout += len; // byte count
+       increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
+       sp->cout_delta += len;
        sp->pout++;
        udp_tx += len;
-       sess_count[s].cout += len;      // To send to master..
+
+       sess_local[s].cout += len;      // To send to master..
+       sess_local[s].pout++;
 }
 
+// process outgoing (to tunnel) IPv6
 //
-// Helper routine for the TBF filters.
-// Used to send queued data in to the user!
-//
-static void send_ipout(sessionidt s, uint8_t *buf, int len)
+static void processipv6out(uint8_t * buf, int len)
 {
+       sessionidt s;
        sessiont *sp;
        tunnelidt t;
        in_addr_t ip;
+       struct in6_addr ip6;
+
+       uint8_t *data = buf;    // Keep a copy of the originals.
+       int size = len;
 
        uint8_t b[MAXETHER + 20];
 
-       if (len < 0 || len > MAXETHER)
+       CSTAT(processipv6out);
+
+       if (len < MIN_IP_SIZE)
        {
-               LOG(1, 0, 0, "Odd size IP packet: %d bytes\n", len);
+               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;
        }
 
@@ -890,47 +1321,154 @@ static void send_ipout(sessionidt s, uint8_t *buf, int len)
        buf += 4;
        len -= 4;
 
-       ip = *(in_addr_t *)(buf + 16);
-
-       if (!session[s].ip)
+       // 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;
+       }
+       if (session[s].bundle && bundle[session[s].bundle].num_of_links > 1)
+       {
+               bundleidt bid = session[s].bundle;
+               s = bundle[bid].members[bundle[bid].current_ses = ++bundle[bid].current_ses % bundle[bid].num_of_links];
+               LOG(3, s, session[s].tunnel, "MPPP: Session number becomes: %d\n", s);
+       }
        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, PPPIP);
+               uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIPV6, 0, 0, 0);
                if (!p) return;
                tunnelsend(b, len + (p-b), t); // send it...
        }
 
-       // Snooping this session.
+       // Snooping this session, send it to intercept box
        if (sp->snoop_ip && sp->snoop_port)
                snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
 
-       sp->cout += len; // byte count
-       sp->total_cout += len; // byte count
+       increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
+       sp->cout_delta += len;
        sp->pout++;
        udp_tx += len;
-       sess_count[s].cout += len;      // To send to master..
-}
 
-// add an AVP (16 bit)
-static void control16(controlt * c, uint16_t avp, uint16_t val, uint8_t m)
-{
-       uint16_t l = (m ? 0x8008 : 0x0008);
-       *(uint16_t *) (c->buf + c->length + 0) = htons(l);
-       *(uint16_t *) (c->buf + c->length + 2) = htons(0);
-       *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
-       *(uint16_t *) (c->buf + c->length + 6) = htons(val);
-       c->length += 8;
+       sess_local[s].cout += len;      // To send to master..
+       sess_local[s].pout++;
 }
 
-// add an AVP (32 bit)
-static void control32(controlt * c, uint16_t avp, uint32_t val, uint8_t m)
+//
+// Helper routine for the TBF filters.
+// Used to send queued data in to the user!
+//
+static void send_ipout(sessionidt s, uint8_t *buf, int len)
+{
+       sessiont *sp;
+       tunnelidt t;
+       in_addr_t ip;
+
+       uint8_t b[MAXETHER + 20];
+
+       if (len < 0 || len > MAXETHER)
+       {
+               LOG(1, 0, 0, "Odd size IP packet: %d bytes\n", len);
+               return;
+       }
+
+       // Skip the tun header
+       buf += 4;
+       len -= 4;
+
+       ip = *(in_addr_t *)(buf + 16);
+
+       if (!session[s].ip)
+               return;
+
+       t = session[s].tunnel;
+       sp = &session[s];
+
+       LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
+
+       // Add on L2TP header
+       {
+               uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIP, 0, 0, 0);
+               if (!p) return;
+               tunnelsend(b, len + (p-b), t); // send it...
+       }
+
+       // Snooping this session.
+       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++;
+}
+
+// add an AVP (16 bit)
+static void control16(controlt * c, uint16_t avp, uint16_t val, uint8_t m)
+{
+       uint16_t l = (m ? 0x8008 : 0x0008);
+       *(uint16_t *) (c->buf + c->length + 0) = htons(l);
+       *(uint16_t *) (c->buf + c->length + 2) = htons(0);
+       *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
+       *(uint16_t *) (c->buf + c->length + 6) = htons(val);
+       c->length += 8;
+}
+
+// add an AVP (32 bit)
+static void control32(controlt * c, uint16_t avp, uint32_t val, uint8_t m)
 {
        uint16_t l = (m ? 0x800A : 0x000A);
        *(uint16_t *) (c->buf + c->length + 0) = htons(l);
@@ -940,7 +1478,7 @@ 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);
@@ -952,7 +1490,7 @@ static void controls(controlt * c, uint16_t avp, char *val, uint8_t m)
 }
 
 // add a binary AVP
-static void controlb(controlt * c, uint16_t avp, char *val, unsigned int len, uint8_t m)
+static void controlb(controlt * c, uint16_t avp, uint8_t *val, unsigned int len, uint8_t m)
 {
        uint16_t l = ((m ? 0x8000 : 0) + len + 6);
        *(uint16_t *) (c->buf + c->length + 0) = htons(l);
@@ -999,11 +1537,11 @@ 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, sessionidt far, tunnelidt t)
 {
        *(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
@@ -1035,7 +1573,7 @@ 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)
@@ -1073,7 +1611,7 @@ void throttle_session(sessionidt s, int rate_in, int rate_out)
 // add/remove filters from session (-1 = no change)
 void filter_session(sessionidt s, int filter_in, int filter_out)
 {
-       if (!session[s].tunnel)
+       if (!session[s].opened)
                return; // No-one home.
 
        if (!*session[s].user)
@@ -1109,16 +1647,16 @@ 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 const *reason, int cdn_result, int cdn_error, int term_cause)
 {
        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
        }
 
@@ -1129,25 +1667,22 @@ 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;
-               if (!r)
+               uint16_t r = radiusnew(s);
+               if (r)
                {
-                       if (!(r = radiusnew(s)))
+                       // stop, if not already trying
+                       if (radius[r].state != RADIUSSTOP)
                        {
-                               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));
+                               radius[r].term_cause = term_cause;
+                               radius[r].term_msg = reason;
+                               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))
@@ -1175,87 +1710,171 @@ void sessionshutdown(sessionidt s, char *reason)
                }
                else
                        free_ip_address(s);
+
+               // unroute IPv6, if setup
+               if (session[s].ppp.ipv6cp == Opened && session[s].ipv6prefixlen)
+                       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 (cdn_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 (cdn_error)
+               {
+                       uint8_t buf[4];
+                       *(uint16_t *) buf     = htons(cdn_result);
+                       *(uint16_t *) (buf+2) = htons(cdn_error);
+                       controlb(c, 1, buf, 4, 1);
+               }
+               else
+                       control16(c, 1, cdn_result, 1);
+
                control16(c, 14, s, 1);   // assigned session (our end)
-               controladd(c, session[s].tunnel, s); // send the message
+               controladd(c, session[s].far, session[s].tunnel); // 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--;
        if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
 
+       // clear PPP state
+       memset(&session[s].ppp, 0, sizeof(session[s].ppp));
+       sess_local[s].lcp.restart = 0;
+       sess_local[s].ipcp.restart = 0;
+       sess_local[s].ipv6cp.restart = 0;
+       sess_local[s].ccp.restart = 0;
+
        cluster_send_session(s);
 }
 
-void sendipcp(tunnelidt t, sessionidt s)
+void sendipcp(sessionidt s, tunnelidt t)
 {
-       uint8_t buf[MAXCONTROL];
-       uint16_t r = session[s].radius;
+       uint8_t buf[MAXETHER];
        uint8_t *q;
 
        CSTAT(sendipcp);
+       LOG(3, s, t, "IPCP: send ConfigReq\n");
 
-       if (!r)
-               r = radiusnew(s);
-
-       if (radius[r].state != RADIUSIPCP)
+       if (!session[s].unique_id)
        {
-               radius[r].state = RADIUSIPCP;
-               radius[r].try = 0;
+               if (!++last_id) ++last_id; // skip zero
+               session[s].unique_id = last_id;
        }
 
-       radius[r].retry = backoff(radius[r].try++);
-       if (radius[r].try > 10)
-       {
-               radiusclear(r, s);      // Clear radius session.
-               sessionshutdown(s, "No reply on IPCP");
-               return;
-       }
-
-       q = makeppp(buf,sizeof(buf), 0, 0, t, s, PPPIPCP);
+       q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPIPCP, 0, 0, 0);
        if (!q) return;
 
        *q = ConfigReq;
-       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;
+       q[1] = session[s].unique_id & 0xf;      // ID, dont care, we only send one type of request
+       *(uint16_t *) (q + 2) = htons(10);      // packet length
+       q[4] = 3;                               // ip address option
+       q[5] = 6;                               // option length
        *(in_addr_t *) (q + 6) = config->peer_address ? config->peer_address :
                                 config->bind_address ? config->bind_address :
                                 my_address; // send my IP
 
        tunnelsend(buf, 10 + (q - buf), t); // send it
-       session[s].flags &= ~SF_IPCP_ACKED;     // Clear flag.
+       restart_timer(s, ipcp);
 }
 
-// kill a session now
-static void sessionkill(sessionidt s, char *reason)
+void sendipv6cp(sessionidt s, tunnelidt t)
 {
+       uint8_t buf[MAXETHER];
+       uint8_t *q;
 
-       CSTAT(sessionkill);
+       CSTAT(sendipv6cp);
+       LOG(3, s, t, "IPV6CP: send ConfigReq\n");
 
-       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
+       q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPIPV6CP, 0, 0, 0);
+       if (!q) return;
 
-       LOG(2, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
+       *q = ConfigReq;
+       q[1] = session[s].unique_id & 0xf;      // ID, don't care, we
+                                               // only send one type
+                                               // of request
+       *(uint16_t *) (q + 2) = htons(14);
+       q[4] = 1;                               // interface identifier option
+       q[5] = 10;                              // option length
+       *(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
+       restart_timer(s, ipv6cp);
+}
 
+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;
-       cli_session_actions[s].action = 0;
+}
+
+// kill a session now
+void sessionkill(sessionidt s, char *reason)
+{
+       bundleidt b;
+
+       CSTAT(sessionkill);
+
+       if (!session[s].opened) // not alive
+               return;
+
+       if (session[s].next)
+       {
+               LOG(0, s, session[s].tunnel, "Tried to kill a session with next pointer set (%d)\n", session[s].next);
+               return;
+       }
+
+       session[s].die = TIME;
+       sessionshutdown(s, reason, CDN_ADMIN_DISC, TERM_ADMIN_RESET);  // 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);
+       if ((b = session[s].bundle))
+       {
+               // This session was part of a bundle
+               bundle[b].num_of_links--;
+               LOG(3, s, 0, "MPPP: Dropping member link: %d from bundle %d\n",s,b);
+               if (bundle[b].num_of_links == 0)
+               {
+                       bundleclear(b);
+                       LOG(3, s, 0, "MPPP: Kill bundle: %d (No remaing member links)\n",b);
+               }
+               else
+               {
+                       // Adjust the members array to accomodate the new change
+                       uint8_t mem_num = 0;
+                       // It should be here num_of_links instead of num_of_links-1 (previous instruction "num_of_links--")
+                       if (bundle[b].members[bundle[b].num_of_links] != s)
+                       {
+                               uint8_t ml;
+                               for (ml = 0; ml<bundle[b].num_of_links; ml++)
+                               {
+                                       if (bundle[b].members[ml] == s)
+                                       {
+                                               mem_num = ml;
+                                               break;
+                                       }
+                               }
+                               bundle[b].members[mem_num] = bundle[b].members[bundle[b].num_of_links];
+                               LOG(3, s, 0, "MPPP: Adjusted member links array\n");
+                       }
+               }
+               cluster_send_bundle(b);
+       }
+       sessionclear(s);
        cluster_send_session(s);
 }
 
@@ -1266,6 +1885,13 @@ static void tunnelclear(tunnelidt t)
        tunnel[t].state = TUNNELFREE;
 }
 
+static void bundleclear(bundleidt b)
+{
+       if (!b) return;
+       memset(&bundle[b], 0, sizeof(bundle[b]));
+       bundle[b].state = BUNDLEFREE;
+}
+
 // kill a tunnel now
 static void tunnelkill(tunnelidt t, char *reason)
 {
@@ -1286,19 +1912,19 @@ 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;
 
@@ -1313,26 +1939,47 @@ 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, CDN_NONE, TERM_ADMIN_RESET);
 
        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)
+               {
+                       uint8_t 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, 0, t);            // send the message
        }
 }
 
 // read and process packet on tunnel (UDP)
-void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
+void processudp(uint8_t *buf, int len, struct sockaddr_in *addr)
 {
-       char *chapresponse = NULL;
+       uint8_t *chapresponse = NULL;
        uint16_t l = len, t = 0, s = 0, ns = 0, nr = 0;
        uint8_t *p = buf + 2;
 
@@ -1396,17 +2043,20 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
                return;
        }
        l -= (p - buf);
+
+       // used to time out old tunnels
+       if (t && tunnel[t].state == TUNNELOPEN)
+               tunnel[t].lastrec = time_now;
+
        if (*buf & 0x80)
        {                          // 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;
                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
 
@@ -1416,7 +2066,10 @@ 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);
@@ -1482,9 +2135,6 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
                        return;
                }
 
-               // This is used to time out old tunnels
-               tunnel[t].lastrec = time_now;
-
                // check sequence of this message
                {
                        int skip = tunnel[t].window; // track how many in-window packets are still in queue
@@ -1526,71 +2176,118 @@ 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;
+
+                       // default disconnect cause/message on receipt
+                       // of CDN (set to more specific value from
+                       // attribute 46 if present below).
+                       int disc_cause = TERM_NAS_REQUEST;
+                       char const *disc_reason = "Closed (Received CDN).";
+
                        // 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)
+                                       if (!*config->l2tp_secret)
                                        {
                                                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);
+                               LOG(4, s, t, "   AVP %d (%s) len %d%s%s\n", mtype, l2tp_avp_name(mtype), n,
+                                       flags & 0x40 ? ", hidden" : "", flags & 0x80 ? ", mandatory" : "");
+
                                switch (mtype)
                                {
                                case 0:     // message type
                                        message = ntohs(*(uint16_t *) b);
-                                       LOG(4, s, t, "   Message type = %d (%s)\n", *b, l2tp_message_type(message));
-                                       mandatorymessage = flags;
+                                       mandatory = flags & 0x80;
+                                       LOG(4, s, t, "   Message type = %d (%s)\n", *b, l2tp_code(message));
                                        break;
                                case 1:     // result code
                                        {
@@ -1598,18 +2295,18 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
                                                const char* resdesc = "(unknown)";
                                                if (message == 4)
                                                { /* StopCCN */
-                                                       resdesc = stopccn_result_code(rescode);
+                                                       resdesc = l2tp_stopccn_result_code(rescode);
                                                }
                                                else if (message == 14)
                                                { /* CDN */
-                                                       resdesc = cdn_result_code(rescode);
+                                                       resdesc = l2tp_cdn_result_code(rescode);
                                                }
 
                                                LOG(4, s, t, "   Result Code %d: %s\n", rescode, resdesc);
                                                if (n >= 4)
                                                {
                                                        uint16_t errcode = ntohs(*(uint16_t *)(b + 2));
-                                                       LOG(4, s, t, "   Error Code %d: %s\n", errcode, error_code(errcode));
+                                                       LOG(4, s, t, "   Error Code %d: %s\n", errcode, l2tp_error_code(errcode));
                                                }
                                                if (n > 4)
                                                        LOG(4, s, t, "   Error String: %.*s\n", n-4, b+4);
@@ -1625,32 +2322,31 @@ 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
                                                }
                                        }
                                        break;
                                case 3:     // framing capabilities
-//                                     LOG(4, s, t, "Framing capabilities\n");
                                        break;
                                case 4:     // bearer capabilities
-//                                     LOG(4, s, t, "Bearer capabilities\n");
                                        break;
                                case 5:         // tie breaker
                                        // We never open tunnels, so we don't care about tie breakers
-//                                     LOG(4, s, t, "Tie breaker\n");
                                        continue;
                                case 6:     // firmware revision
-//                                     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
@@ -1690,13 +2386,13 @@ 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
@@ -1709,8 +2405,9 @@ 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);
@@ -1723,8 +2420,9 @@ 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);
@@ -1738,21 +2436,20 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
                                case 29:    // Proxy Authentication Type
                                        {
                                                uint16_t atype = ntohs(*(uint16_t *)b);
-                                               LOG(4, s, t, "   Proxy Auth Type %d (%s)\n", atype, auth_type(atype));
-                                               requestchap = (atype == 2);
+                                               LOG(4, s, t, "   Proxy Auth Type %d (%s)\n", atype, ppp_auth_type(atype));
                                                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");
                                                break;
                                        }
@@ -1760,30 +2457,22 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
                                        {
                                                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;
                                                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 == 7) // Protocol-Field-Compression
-                                                               aflags |= SESSIONPFC;
+                                                               aflags |= SESSION_PFC;
                                                        else if (*p == 8) // Address-and-Control-Field-Compression
-                                                               aflags |= SESSIONACFC;
+                                                               aflags |= SESSION_ACFC;
                                                        p += p[1];
                                                }
                                        }
@@ -1797,32 +2486,123 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
                                case 36:    // Random Vector
                                        LOG(4, s, t, "   Random Vector received.  Enabled AVP Hiding.\n");
                                        memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
+                                       if (n > sizeof(session[s].random_vector))
+                                               n = sizeof(session[s].random_vector);
                                        memcpy(session[s].random_vector, b, n);
                                        session[s].random_vector_length = n;
                                        break;
+                               case 46:    // ppp disconnect cause
+                                       if (n >= 5)
+                                       {
+                                               uint16_t code = ntohs(*(uint16_t *) b);
+                                               uint16_t proto = ntohs(*(uint16_t *) (b + 2));
+                                               uint8_t dir = *(b + 4);
+
+                                               LOG(4, s, t, "   PPP disconnect cause "
+                                                       "(code=%u, proto=%04X, dir=%u, msg=\"%.*s\")\n",
+                                                       code, proto, dir, n - 5, b + 5);
+
+                                               switch (code)
+                                               {
+                                               case 1: // admin disconnect
+                                                       disc_cause = TERM_ADMIN_RESET;
+                                                       disc_reason = "Administrative disconnect";
+                                                       break;
+                                               case 3: // lcp terminate
+                                                       if (dir != 2) break; // 1=peer (LNS), 2=local (LAC)
+                                                       disc_cause = TERM_USER_REQUEST;
+                                                       disc_reason = "Normal disconnection";
+                                                       break;
+                                               case 4: // compulsory encryption unavailable
+                                                       if (dir != 1) break; // 1=refused by peer, 2=local
+                                                       disc_cause = TERM_USER_ERROR;
+                                                       disc_reason = "Compulsory encryption refused";
+                                                       break;
+                                               case 5: // lcp: fsm timeout
+                                                       disc_cause = TERM_PORT_ERROR;
+                                                       disc_reason = "LCP: FSM timeout";
+                                                       break;
+                                               case 6: // lcp: no recognisable lcp packets received
+                                                       disc_cause = TERM_PORT_ERROR;
+                                                       disc_reason = "LCP: no recognisable LCP packets";
+                                                       break;
+                                               case 7: // lcp: magic-no error (possibly looped back)
+                                                       disc_cause = TERM_PORT_ERROR;
+                                                       disc_reason = "LCP: magic-no error (possible loop)";
+                                                       break;
+                                               case 8: // lcp: echo request timeout
+                                                       disc_cause = TERM_PORT_ERROR;
+                                                       disc_reason = "LCP: echo request timeout";
+                                                       break;
+                                               case 13: // auth: fsm timeout
+                                                       disc_cause = TERM_SERVICE_UNAVAILABLE;
+                                                       disc_reason = "Authentication: FSM timeout";
+                                                       break;
+                                               case 15: // auth: unacceptable auth protocol
+                                                       disc_cause = TERM_SERVICE_UNAVAILABLE;
+                                                       disc_reason = "Unacceptable authentication protocol";
+                                                       break;
+                                               case 16: // auth: authentication failed
+                                                       disc_cause = TERM_SERVICE_UNAVAILABLE;
+                                                       disc_reason = "Authentication failed";
+                                                       break;
+                                               case 17: // ncp: fsm timeout
+                                                       disc_cause = TERM_SERVICE_UNAVAILABLE;
+                                                       disc_reason = "NCP: FSM timeout";
+                                                       break;
+                                               case 18: // ncp: no ncps available
+                                                       disc_cause = TERM_SERVICE_UNAVAILABLE;
+                                                       disc_reason = "NCP: no NCPs available";
+                                                       break;
+                                               case 19: // ncp: failure to converge on acceptable address
+                                                       disc_cause = TERM_SERVICE_UNAVAILABLE;
+                                                       disc_reason = (dir == 1)
+                                                               ? "NCP: too many Configure-Naks received from peer"
+                                                               : "NCP: too many Configure-Naks sent to peer";
+                                                       break;
+                                               case 20: // ncp: user not permitted to use any address
+                                                       disc_cause = TERM_SERVICE_UNAVAILABLE;
+                                                       disc_reason = (dir == 1)
+                                                               ? "NCP: local link address not acceptable to peer"
+                                                               : "NCP: remote link address not acceptable";
+                                                       break;
+                                               }
+                                       }
+                                       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)
                                {
                                case 1:       // SCCRQ - Start Control Connection Request
+                                       tunnel[t].state = TUNNELOPENING;
+                                       if (main_quit != QUIT_SHUTDOWN)
                                        {
                                                controlt *c = controlnew(2); // sending SCCRP
                                                control16(c, 2, version, 1); // protocol version
                                                control32(c, 3, 3, 1); // framing
-                                               controls(c, 7, tunnel[t].hostname, 1); // host name (TBA)
+                                               controls(c, 7, hostname, 1); // host name
                                                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, 0, t); // send the resply
+                                       }
+                                       else
+                                       {
+                                               tunnelshutdown(t, "Shutting down", 6, 0, 0);
                                        }
-                                       tunnel[t].state = TUNNELOPENING;
                                        break;
                                case 2:       // SCCRP
                                        tunnel[t].state = TUNNELOPEN;
@@ -1833,8 +2613,7 @@ 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
@@ -1849,15 +2628,9 @@ 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 && main_quit != QUIT_SHUTDOWN)
                                        {
-                                               uint16_t r;
-                                               controlt *c;
+                                               controlt *c = controlnew(11); // ICRP
 
                                                s = sessionfree;
                                                sessionfree = session[s].next;
@@ -1866,56 +2639,71 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
                                                if (s > config->cluster_highest_sessionid)
                                                        config->cluster_highest_sessionid = s;
 
-                                               // make a RADIUS session
-                                               if (!(r = radiusnew(s)))
-                                               {
-                                                       LOG(1, s, t, "No free RADIUS sessions for ICRQ\n");
-                                                       sessionkill(s, "no free RADIUS sesions");
-                                                       return;
-                                               }
-
-                                               c = controlnew(11); // sending ICRP
-                                               session[s].id = sessionid++;
-                                               session[s].opened = time(NULL);
+                                               session[s].opened = time_now;
                                                session[s].tunnel = t;
                                                session[s].far = asession;
                                                session[s].last_packet = time_now;
                                                LOG(3, s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
                                                control16(c, 14, s, 1); // assigned session
-                                               controladd(c, t, s); // send the reply
+                                               controladd(c, asession, t); // 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);
+
+                                               session[s].ppp.phase = Establish;
+                                               session[s].ppp.lcp = Starting;
+
                                                STAT(session_created);
+                                               break;
                                        }
-                                       break;
+
+                                       {
+                                               controlt *c = controlnew(14); // CDN
+                                               if (!sessionfree)
+                                               {
+                                                       STAT(session_overflow);
+                                                       LOG(1, 0, t, "No free sessions\n");
+                                                       control16(c, 1, 4, 0); // temporary lack of resources
+                                               }
+                                               else
+                                                       control16(c, 1, 2, 7); // shutting down, try another
+
+                                               controladd(c, asession, t); // send the message
+                                       }
+                                       return;
                                case 11:      // ICRP
                                        // TBA
                                        break;
                                case 12:      // ICCN
                                        if (amagic == 0) amagic = time_now;
                                        session[s].magic = amagic; // set magic number
-                                       session[s].l2tp_flags = aflags; // set flags received
-                                       LOG(3, s, t, "Magic %X Flags %X\n", amagic, aflags);
+                                       session[s].flags = aflags; // set flags received
+                                       session[s].mru = PPPoE_MRU; // default
                                        controlnull(t); // ack
-                                       // In CHAP state, request PAP instead
-                                       if (requestchap)
-                                               initlcp(t, s);
+
+                                       // start LCP
+                                       sess_local[s].lcp_authtype = config->radius_authprefer;
+                                       sess_local[s].ppp_mru = MRU;
+
+                                       // Set multilink options before sending initial LCP packet
+                                       sess_local[s].mp_mrru = 1614;
+                                       sess_local[s].mp_epdis = config->bind_address ? config->bind_address : my_address;
+
+                                       sendlcp(s, t);
+                                       change_state(s, lcp, RequestSent);
                                        break;
+
                                case 14:      // CDN
                                        controlnull(t); // ack
-                                       sessionshutdown(s, "Closed (Received CDN)");
+                                       sessionshutdown(s, disc_reason, CDN_NONE, disc_cause);
                                        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;
@@ -1930,7 +2718,7 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
        }
        else
        {                          // data
-               uint16_t prot;
+               uint16_t proto;
 
                LOG_HEX(5, "Receive Tunnel Data", p, l);
                if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
@@ -1946,17 +2734,17 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
                }
                if (*p & 1)
                {
-                       prot = *p++;
+                       proto = *p++;
                        l--;
                }
                else
                {
-                       prot = ntohs(*(uint16_t *) p);
+                       proto = ntohs(*(uint16_t *) p);
                        p += 2;
                        l -= 2;
                }
 
-               if (s && !session[s].tunnel)    // Is something wrong??
+               if (s && !session[s].opened)    // Is something wrong??
                {
                        if (!config->cluster_iam_master)
                        {
@@ -1966,44 +2754,82 @@ 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;
                }
 
-               if (prot == PPPPAP)
+               if (proto == PPPPAP)
+               {
+                       session[s].last_packet = time_now;
+                       if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
+                       processpap(s, t, p, l);
+               }
+               else if (proto == PPPCHAP)
                {
                        session[s].last_packet = time_now;
                        if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
-                       processpap(t, s, p, l);
+                       processchap(s, t, p, l);
                }
-               else if (prot == PPPCHAP)
+               else if (proto == PPPLCP)
                {
                        session[s].last_packet = time_now;
                        if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
-                       processchap(t, s, p, l);
+                       processlcp(s, t, p, l);
                }
-               else if (prot == PPPLCP)
+               else if (proto == PPPIPCP)
                {
                        session[s].last_packet = time_now;
                        if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
-                       processlcp(t, s, p, l);
+                       processipcp(s, t, p, l);
                }
-               else if (prot == PPPIPCP)
+               else if (proto == PPPIPV6CP && config->ipv6_prefix.s6_addr[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; }
-                       processipcp(t, s, p, l);
+                       processipv6cp(s, t, p, l);
                }
-               else if (prot == PPPCCP)
+               else if (proto == PPPCCP)
                {
                        session[s].last_packet = time_now;
                        if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
-                       processccp(t, s, p, l);
+                       processccp(s, t, p, l);
+               }
+               else if (proto == PPPIP)
+               {
+                       if (session[s].die)
+                       {
+                               LOG(4, s, t, "Session %d is closing.  Don't process PPP packets\n", s);
+                               return;              // closing session, PPP not processed
+                       }
+
+                       session[s].last_packet = time_now;
+                       if (session[s].walled_garden && !config->cluster_iam_master)
+                       {
+                               master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
+                               return;
+                       }
+
+                       processipin(s, t, p, l);
+               }
+               else if (proto == PPPMP)
+               {
+                       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;
+                       }
+
+                       processmpin(s, t, p, l);
                }
-               else if (prot == PPPIP)
+               else if (proto == PPPIPV6 && config->ipv6_prefix.s6_addr[0])
                {
                        if (session[s].die)
                        {
@@ -2018,12 +2844,18 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
                                return;
                        }
 
-                       processipin(t, s, p, l);
+                       processipv6in(s, t, p, l);
+               }
+               else if (session[s].ppp.lcp == Opened)
+               {
+                       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; }
+                       protoreject(s, t, p, l, proto);
                }
                else
                {
-                       STAT(tunnel_rx_errors);
-                       LOG(1, s, t, "Unknown PPP protocol %04X\n", prot);
+                       LOG(2, s, t, "Unknown PPP protocol 0x%04X received in LCP %s state\n",
+                               proto, ppp_state(session[s].ppp.lcp));
                }
        }
 }
@@ -2048,45 +2880,68 @@ 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])
+               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
@@ -2106,14 +2961,17 @@ static int regular_cleanups(void)
                                                tunnelsend(c->buf, c->length, t);
                                                c = c->next;
                                        }
+
+                               t_actions++;
                        }
                }
                // Send hello
-               if (tunnel[t].state == TUNNELOPEN && tunnel[t].lastrec < TIME + 600)
+               if (tunnel[t].state == TUNNELOPEN && !tunnel[t].controlc && (time_now - tunnel[t].lastrec) > 60)
                {
                        controlt *c = controlnew(6); // sending HELLO
-                       controladd(c, t, 0); // send the message
+                       controladd(c, 0, t); // send the message
                        LOG(3, 0, t, "Sending HELLO message\n");
+                       t_actions++;
                }
 
                // Check for tunnel changes requested from the CLI
@@ -2123,63 +2981,218 @@ 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)
+               // check for timed out sessions
+               if (session[s].timeout)
                {
-                       sessionkill(s, "Expired");
-                       if (++count >= MAX_ACTIONS) break;
-                       continue;
+                       bundleidt bid = session[s].bundle;
+                       if (bid)
+                       {
+                               clockt curr_time = time_now;
+                               if (curr_time - bundle[bid].last_check >= 1)
+                               {
+                                       bundle[bid].online_time += (curr_time-bundle[bid].last_check)*bundle[bid].num_of_links;
+                                       bundle[bid].last_check = curr_time;
+                                       if (bundle[bid].online_time >= session[s].timeout)
+                                       {
+                                               int ses;
+                                               for (ses = bundle[bid].num_of_links - 1; ses >= 0; ses--)
+                                               {
+                                                       sessionshutdown(bundle[bid].members[ses], "Session timeout", CDN_ADMIN_DISC, TERM_SESSION_TIMEOUT);
+                                                       s_actions++;
+                                                       continue;
+                                               }
+                                       }
+                               }
+                       }
+                       else if (session[s].timeout <= time_now - session[s].opened)
+                       {
+                               sessionshutdown(s, "Session timeout", CDN_ADMIN_DISC, TERM_SESSION_TIMEOUT);
+                               s_actions++;
+                               continue;
+                       }
+               }
+
+               // PPP timeouts
+               if (sess_local[s].lcp.restart <= time_now)
+               {
+                       int next_state = session[s].ppp.lcp;
+                       switch (session[s].ppp.lcp)
+                       {
+                       case RequestSent:
+                       case AckReceived:
+                               next_state = RequestSent;
+
+                       case AckSent:
+                               if (sess_local[s].lcp.conf_sent < config->ppp_max_configure)
+                               {
+                                       LOG(3, s, session[s].tunnel, "No ACK for LCP ConfigReq... resending\n");
+                                       sendlcp(s, session[s].tunnel);
+                                       change_state(s, lcp, next_state);
+                               }
+                               else
+                               {
+                                       sessionshutdown(s, "No response to LCP ConfigReq.", CDN_ADMIN_DISC, TERM_LOST_SERVICE);
+                                       STAT(session_timeout);
+                               }
+
+                               s_actions++;
+                       }
+
+                       if (session[s].die)
+                               continue;
+               }
+
+               if (sess_local[s].ipcp.restart <= time_now)
+               {
+                       int next_state = session[s].ppp.ipcp;
+                       switch (session[s].ppp.ipcp)
+                       {
+                       case RequestSent:
+                       case AckReceived:
+                               next_state = RequestSent;
+
+                       case AckSent:
+                               if (sess_local[s].ipcp.conf_sent < config->ppp_max_configure)
+                               {
+                                       LOG(3, s, session[s].tunnel, "No ACK for IPCP ConfigReq... resending\n");
+                                       sendipcp(s, session[s].tunnel);
+                                       change_state(s, ipcp, next_state);
+                               }
+                               else
+                               {
+                                       sessionshutdown(s, "No response to IPCP ConfigReq.", CDN_ADMIN_DISC, TERM_LOST_SERVICE);
+                                       STAT(session_timeout);
+                               }
+
+                               s_actions++;
+                       }
+
+                       if (session[s].die)
+                               continue;
+               }
+
+               if (sess_local[s].ipv6cp.restart <= time_now)
+               {
+                       int next_state = session[s].ppp.ipv6cp;
+                       switch (session[s].ppp.ipv6cp)
+                       {
+                       case RequestSent:
+                       case AckReceived:
+                               next_state = RequestSent;
+
+                       case AckSent:
+                               if (sess_local[s].ipv6cp.conf_sent < config->ppp_max_configure)
+                               {
+                                       LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq... resending\n");
+                                       sendipv6cp(s, session[s].tunnel);
+                                       change_state(s, ipv6cp, next_state);
+                               }
+                               else
+                               {
+                                       LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq\n");
+                                       change_state(s, ipv6cp, Stopped);
+                               }
+
+                               s_actions++;
+                       }
+               }
+
+               if (sess_local[s].ccp.restart <= time_now)
+               {
+                       int next_state = session[s].ppp.ccp;
+                       switch (session[s].ppp.ccp)
+                       {
+                       case RequestSent:
+                       case AckReceived:
+                               next_state = RequestSent;
+
+                       case AckSent:
+                               if (sess_local[s].ccp.conf_sent < config->ppp_max_configure)
+                               {
+                                       LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq... resending\n");
+                                       sendccp(s, session[s].tunnel);
+                                       change_state(s, ccp, next_state);
+                               }
+                               else
+                               {
+                                       LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq\n");
+                                       change_state(s, ccp, Stopped);
+                               }
+
+                               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.", CDN_ADMIN_DISC, TERM_LOST_SERVICE);
                        STAT(session_timeout);
-                       if (++count >= MAX_ACTIONS) break;
+                       s_actions++;
                        continue;
                }
 
-               // No data in IDLE_TIMEOUT seconds, send LCP ECHO
-               if (session[s].user[0] && (time_now - session[s].last_packet >= ECHO_TIMEOUT))
+               // No data in ECHO_TIMEOUT seconds, send LCP ECHO
+               if (session[s].ppp.phase >= Establish && (time_now - session[s].last_packet >= ECHO_TIMEOUT) &&
+                       (time_now - sess_local[s].last_echo >= ECHO_TIMEOUT))
                {
-                       uint8_t b[MAXCONTROL] = {0};
+                       uint8_t b[MAXETHER];
 
-                       uint8_t *q = makeppp(b, sizeof(b), 0, 0, session[s].tunnel, s, PPPLCP);
+                       uint8_t *q = makeppp(b, sizeof(b), 0, 0, s, session[s].tunnel, PPPLCP, 1, 0, 0);
                        if (!q) continue;
 
                        *q = EchoReq;
                        *(uint8_t *)(q + 1) = (time_now % 255); // ID
                        *(uint16_t *)(q + 2) = htons(8); // Length
-                       *(uint32_t *)(q + 4) = 0; // Magic Number (not supported)
+                       *(uint32_t *)(q + 4) = session[s].ppp.lcp == Opened ? htonl(session[s].magic) : 0; // Magic Number
 
                        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;
+                       sess_local[s].last_echo = time_now;
+                       s_actions++;
                }
 
                // Check for actions requested from the CLI
@@ -2191,8 +3204,9 @@ 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.", CDN_ADMIN_DISC, TERM_ADMIN_RESET);
                                a = 0; // dead, no need to check for other actions
+                               s_actions++;
                        }
 
                        if (a & CLI_SESS_NOSNOOP)
@@ -2200,6 +3214,7 @@ 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)
@@ -2210,6 +3225,7 @@ 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++;
                        }
 
@@ -2217,6 +3233,7 @@ 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)
@@ -2226,6 +3243,7 @@ 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++;
                        }
 
@@ -2233,6 +3251,7 @@ 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)
@@ -2242,42 +3261,41 @@ 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)
-               {
-                       // 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)
+               // 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 for shutdown sessions
-                       next_shut_acct = TIME + ACCT_SHUT_TIME;
-                       if (shut_acct_n)
-                               dump_acct_info(0);
+                       int rad = radiusnew(s);
+                       if (!rad)
+                       {
+                               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(rad, 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??
@@ -2287,6 +3305,53 @@ 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 (main_quit == QUIT_SHUTDOWN)
+       {
+               static int dropped = 0;
+               if (!dropped)
+               {
+                       int i;
+
+                       LOG(1, 0, 0, "Dropping sessions and tunnels\n");
+                       for (i = 1; i < MAXTUNNEL; i++)
+                               if (tunnel[i].ip || tunnel[i].state)
+                                       tunnelshutdown(i, "L2TPNS Closing", 6, 0, 0);
+
+                       dropped = 1;
+               }
+       }
+
        if (start_busy_wait == 0)
                start_busy_wait = TIME;
 
@@ -2328,80 +3393,119 @@ 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: cli, cluster, tun, udp, control, dae
+#define BASE_FDS       6
+
+// 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;
-
-       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;
+       struct epoll_event events[BASE_FDS + RADIUS_FDS + EXTRA_FDS];
+       int maxevent = sizeof(events)/sizeof(*events);
 
-       while (!main_quit || still_busy())
+       if ((epollfd = epoll_create(maxevent)) < 0)
        {
-               fd_set r;
-               int n = readset_n;
-#ifdef BGP
-               fd_set w;
-               int bgp_set[BGP_NUM_PEERS];
-#endif /* BGP */
+               LOG(0, 0, 0, "epoll_create failed: %s\n", strerror(errno));
+               exit(1);
+       }
 
-               if (config->reload_config)
+       LOG(4, 0, 0, "Beginning of main loop.  clifd=%d, cluster_sockfd=%d, tunfd=%d, udpfd=%d, controlfd=%d, daefd=%d\n",
+               clifd, cluster_sockfd, tunfd, udpfd, controlfd, daefd);
+
+       /* setup our fds to poll for input */
+       {
+               static struct event_data d[BASE_FDS];
+               struct epoll_event e;
+
+               e.events = EPOLLIN;
+               i = 0;
+
+               if (clifd >= 0)
                {
-                       // Update the config state based on config settings
-                       update_config();
+                       d[i].type = FD_TYPE_CLI;
+                       e.data.ptr = &d[i++];
+                       epoll_ctl(epollfd, EPOLL_CTL_ADD, clifd, &e);
                }
 
-               memcpy(&r, &readset, sizeof(fd_set));
-               to.tv_sec = 0;
-               to.tv_usec = 100000; // 1/10th of a second.
+               d[i].type = FD_TYPE_CLUSTER;
+               e.data.ptr = &d[i++];
+               epoll_ctl(epollfd, EPOLL_CTL_ADD, cluster_sockfd, &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_UDP;
+               e.data.ptr = &d[i++];
+               epoll_ctl(epollfd, EPOLL_CTL_ADD, udpfd, &e);
+
+               d[i].type = FD_TYPE_CONTROL;
+               e.data.ptr = &d[i++];
+               epoll_ctl(epollfd, EPOLL_CTL_ADD, controlfd, &e);
+
+               d[i].type = FD_TYPE_DAE;
+               e.data.ptr = &d[i++];
+               epoll_ctl(epollfd, EPOLL_CTL_ADD, daefd, &e);
+       }
 
 #ifdef BGP
-               FD_ZERO(&w);
-               for (i = 0; i < BGP_NUM_PEERS; i++)
+       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 (main_reload)
                {
-                       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;
-                       }
+                       main_reload = 0;
+                       read_config_file();
+                       config->reload_config++;
+               }
 
-                       if (bgp_set[i] & 2)
-                       {
-                               FD_SET(bgp_peers[i].sock, &w);
-                               if (bgp_peers[i].sock > n)
-                                       n = bgp_peers[i].sock;
-                       }
+               if (config->reload_config)
+               {
+                       config->reload_config = 0;
+                       update_config();
                }
 
-               n = select(n + 1, &r, &w, 0, &to);
-#else /* BGP */
-               n = select(n + 1, &r, 0, 0, &to);
+#ifdef BGP
+               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 ||
@@ -2409,70 +3513,104 @@ static void mainloop(void)
                                continue;
 
                        LOG(0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
-                       main_quit++;
-                       break;
+                       break; // exit
                }
-               else if (n)
+
+               if (n)
                {
                        struct sockaddr_in addr;
-                       int alen, c, s;
+                       struct in_addr local;
+                       socklen_t alen;
+                       int 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;
 
-                       // RADIUS responses
-                       if (config->cluster_iam_master)
-                       {
-                               for (i = 0; i < config->num_radfds; i++)
+                               switch (d->type)
+                               {
+                               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_CLUSTER:   cluster_ready++; break;
+                               case FD_TYPE_TUN:       tun_ready++; break;
+                               case FD_TYPE_UDP:       udp_ready++; break;
+
+                               case FD_TYPE_CONTROL: // nsctl commands
+                                       alen = sizeof(addr);
+                                       s = recvfromto(controlfd, buf, sizeof(buf), MSG_WAITALL, (struct sockaddr *) &addr, &alen, &local);
+                                       if (s > 0) processcontrol(buf, s, &addr, alen, &local);
+                                       n--;
+                                       break;
+
+                               case FD_TYPE_DAE: // DAE requests
+                                       alen = sizeof(addr);
+                                       s = recvfromto(daefd, buf, sizeof(buf), MSG_WAITALL, (struct sockaddr *) &addr, &alen, &local);
+                                       if (s > 0) processdae(buf, s, &addr, alen, &local);
+                                       n--;
+                                       break;
+
+                               case FD_TYPE_RADIUS: // RADIUS response
+                                       alen = sizeof(addr);
+                                       s = recvfrom(radfds[d->index], buf, sizeof(buf), MSG_WAITALL, (struct sockaddr *) &addr, &alen);
+                                       if (s >= 0 && config->cluster_iam_master)
+                                       {
+                                               if (addr.sin_addr.s_addr == config->radiusserver[0] ||
+                                                   addr.sin_addr.s_addr == config->radiusserver[1])
+                                                       processrad(buf, s, d->index);
+                                               else
+                                                       LOG(3, 0, 0, "Dropping RADIUS packet from unknown source %s\n",
+                                                               fmtaddr(addr.sin_addr.s_addr, 0));
+                                       }
+
+                                       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)
@@ -2482,13 +3620,13 @@ 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)
                                        {
@@ -2497,13 +3635,13 @@ 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)
@@ -2513,7 +3651,7 @@ static void mainloop(void)
                                        }
                                        else
                                        {
-                                               FD_CLR(cluster_sockfd, &r);
+                                               cluster_ready = 0;
                                                n--;
                                        }
                                }
@@ -2528,11 +3666,41 @@ static void mainloop(void)
                                        config->multi_read_count, udp_pkts, tun_pkts, cluster_pkts);
 
                                STAT(multi_read_exceeded);
+                               more++;
+                       }
+               }
+
+               if (time_changed)
+               {
+                       double Mbps = 1024.0 * 1024.0 / 8 * time_changed;
+
+                       // Log current traffic stats
+                       snprintf(config->bandwidth, sizeof(config->bandwidth),
+                               "UDP-ETH:%1.0f/%1.0f  ETH-UDP:%1.0f/%1.0f  TOTAL:%0.1f   IN:%u OUT:%u",
+                               (udp_rx / Mbps), (eth_tx / Mbps), (eth_rx / Mbps), (udp_tx / Mbps),
+                               ((udp_tx + udp_rx + eth_tx + eth_rx) / Mbps),
+                               udp_rx_pkt / time_changed, eth_rx_pkt / time_changed);
+                
+                       udp_tx = udp_rx = 0;
+                       udp_rx_pkt = eth_rx_pkt = 0;
+                       eth_tx = eth_rx = 0;
+                       time_changed = 0;
+                
+                       if (config->dump_speed)
+                               printf("%s\n", config->bandwidth);
+                
+                       // Update the internal time counter
+                       strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
+                
+                       {
+                               // Run timer hooks
+                               struct param_timer p = { time_now };
+                               run_plugins(PLUGIN_TIMER, &p);
                        }
                }
 
                        // 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..
 
@@ -2550,9 +3718,11 @@ 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)
@@ -2562,20 +3732,42 @@ 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.
                {
-                       if (regular_cleanups())
+                       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)
                        {
-                               // Did it finish?
-                               next_clean = time_now + 1 ;     // Didn't finish. Check quickly.
+                               regular_cleanups(diff);
+                               last_clean = this_clean;
                        }
-                       else
+               }
+
+               if (*config->accounting_dir)
+               {
+                       static clockt next_acct = 0;
+                       static clockt next_shut_acct = 0;
+
+                       if (next_acct <= TIME)
+                       {
+                               // Dump accounting data
+                               next_acct = TIME + ACCT_TIME;
+                               next_shut_acct = TIME + ACCT_SHUT_TIME;
+                               dump_acct_info(1);
+                       }
+                       else if (next_shut_acct <= TIME)
                        {
-                               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);
                        }
                }
        }
@@ -2590,6 +3782,7 @@ static void mainloop(void)
 
        //
        // Important!!! We MUST not process any packets past this point!
+       LOG(1, 0, 0, "Shutdown complete\n");
 }
 
 static void stripdomain(char *host)
@@ -2662,38 +3855,65 @@ 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_mcast_ttl = 1;
+       config->cluster_master_min_adv = 1;
+       config->ppp_restart_time = 3;
+       config->ppp_max_configure = 10;
+       config->ppp_max_failure = 5;
        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));
                exit(1);
        }
+       if (!(bundle = shared_malloc(sizeof(bundlet) * MAXBUNDLE)))
+       {
+               LOG(0, 0, 0, "Error doing malloc for bundles: %s\n", strerror(errno));
+               exit(1);
+       }
+       if (!(frag = shared_malloc(sizeof(fragmentationt) * MAXBUNDLE)))
+       {
+               LOG(0, 0, 0, "Error doing malloc for fragmentations: %s\n", strerror(errno));
+               exit(1);
+       }
        if (!(session = shared_malloc(sizeof(sessiont) * MAXSESSION)))
        {
                LOG(0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno));
                exit(1);
        }
 
-       if (!(sess_count = shared_malloc(sizeof(sessioncountt) * MAXSESSION)))
+       if (!(sess_local = shared_malloc(sizeof(sessionlocalt) * MAXSESSION)))
        {
-               LOG(0, 0, 0, "Error doing malloc for sessions_count: %s\n", strerror(errno));
+               LOG(0, 0, 0, "Error doing malloc for sess_local: %s\n", strerror(errno));
                exit(1);
        }
 
@@ -2716,15 +3936,6 @@ 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));
@@ -2740,12 +3951,13 @@ static void initdata(int optdebug, char *optconfig)
        memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
 
        memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
+       memset(bundle, 0, sizeof(bundlet) * MAXBUNDLE);
        memset(session, 0, sizeof(sessiont) * MAXSESSION);
        memset(radius, 0, sizeof(radiust) * MAXRADIUS);
        memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
 
                // Put all the sessions on the free list marked as undefined.
-       for (i = 1; i < MAXSESSION - 1; i++)
+       for (i = 1; i < MAXSESSION; i++)
        {
                session[i].next = i + 1;
                session[i].tunnel = T_UNDEF;    // mark it as not filled in.
@@ -2754,9 +3966,13 @@ 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.
 
+       for (i = 1; i < MAXBUNDLE; i++) {
+               bundle[i].state = BUNDLEUNDEF;
+       }
+
        if (!*hostname)
        {
                // Grab my hostname unless it's been specified
@@ -2880,8 +4096,9 @@ 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)
@@ -3030,14 +4247,14 @@ static void initippool()
                else
                {
                        // It's a single ip address
-                       add_to_ip_pool(inet_addr(pool), 0);
+                       add_to_ip_pool(ntohl(inet_addr(pool)), 0);
                }
        }
        fclose(f);
        LOG(1, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
 }
 
-void snoop_send_packet(char *packet, uint16_t size, in_addr_t destination, uint16_t port)
+void snoop_send_packet(uint8_t *packet, uint16_t size, in_addr_t destination, uint16_t port)
 {
        struct sockaddr_in snoop_addr = {0};
        if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
@@ -3059,7 +4276,7 @@ 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)
@@ -3080,10 +4297,12 @@ 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);
        }
@@ -3093,11 +4312,10 @@ 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;
 }
@@ -3171,14 +4389,13 @@ int main(int argc, char *argv[])
        // Start the timer routine off
        time(&time_now);
        strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
-       signal(SIGALRM, sigalrm_handler);
-       siginterrupt(SIGALRM, 0);
 
        initplugins();
        initdata(optdebug, optconfig);
 
        init_cli(hostname);
        read_config_file();
+       update_config();
        init_tbf(config->num_tbfs);
 
        LOG(0, 0, 0, "L2TPNS version " VERSION "\n");
@@ -3225,19 +4442,6 @@ 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);
 
@@ -3245,13 +4449,18 @@ int main(int argc, char *argv[])
        initrad();
        initippool();
 
-       read_state();
+       // seed prng
+       {
+               unsigned seed = time_now ^ getpid();
+               LOG(4, 0, 0, "Seeding the pseudo random generator: %u\n", seed);
+               srand(seed);
+       }
 
-       signal(SIGHUP, sighup_handler);
-       signal(SIGTERM, sigterm_handler);
-       signal(SIGINT, sigterm_handler);
-       signal(SIGQUIT, sigquit_handler);
+       signal(SIGHUP,  sighup_handler);
        signal(SIGCHLD, sigchild_handler);
+       signal(SIGTERM, shutdown_handler);
+       signal(SIGINT,  shutdown_handler);
+       signal(SIGQUIT, shutdown_handler);
 
        // Prevent us from getting paged out
        if (config->lock_pages)
@@ -3262,22 +4471,8 @@ int main(int argc, char *argv[])
                        LOG(0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
        }
 
-       alarm(1);
-
-       // Drop privileges here
-       if (config->target_uid > 0 && geteuid() == 0)
-               setuid(config->target_uid);
-
        mainloop();
 
-#ifdef BGP
-       /* try to shut BGP down cleanly; with luck the sockets will be
-          writable since we're out of the select */
-       for (i = 0; i < BGP_NUM_PEERS; i++)
-               if (bgp_peers[i].state == Established)
-                       bgp_stop(&bgp_peers[i]);
-#endif /* BGP */
-
        /* remove plugins (so cleanup code gets run) */
        plugins_done();
 
@@ -3293,78 +4488,12 @@ int main(int argc, char *argv[])
 
 static void sighup_handler(int sig)
 {
-       if (log_stream && log_stream != stderr)
-       {
-               fclose(log_stream);
-               log_stream = NULL;
-       }
-
-       read_config_file();
-}
-
-static void sigalrm_handler(int sig)
-{
-       // Log current traffic stats
-
-       snprintf(config->bandwidth, sizeof(config->bandwidth),
-               "UDP-ETH:%1.0f/%1.0f  ETH-UDP:%1.0f/%1.0f  TOTAL:%0.1f   IN:%u OUT:%u",
-               (udp_rx / 1024.0 / 1024.0 * 8),
-               (eth_tx / 1024.0 / 1024.0 * 8),
-               (eth_rx / 1024.0 / 1024.0 * 8),
-               (udp_tx / 1024.0 / 1024.0 * 8),
-               ((udp_tx + udp_rx + eth_tx + eth_rx) / 1024.0 / 1024.0 * 8),
-               udp_rx_pkt, eth_rx_pkt);
-
-       udp_tx = udp_rx = 0;
-       udp_rx_pkt = eth_rx_pkt = 0;
-       eth_tx = eth_rx = 0;
-
-       if (config->dump_speed)
-               printf("%s\n", config->bandwidth);
-
-       // Update the internal time counter
-       time(&time_now);
-       strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
-       alarm(1);
-
-       {
-               // Run timer hooks
-               struct param_timer p = { time_now };
-               run_plugins(PLUGIN_TIMER, &p);
-       }
-
-}
-
-static void sigterm_handler(int sig)
-{
-       LOG(1, 0, 0, "Shutting down cleanly\n");
-       if (config->save_state)
-               dump_state();
-
-       main_quit++;
+       main_reload++;
 }
 
-static void sigquit_handler(int sig)
+static void shutdown_handler(int sig)
 {
-       int i;
-
-       LOG(1, 0, 0, "Shutting down without saving sessions\n");
-
-       if (config->cluster_iam_master)
-       {
-               for (i = 1; i < MAXSESSION; i++)
-               {
-                       if (session[i].opened)
-                               sessionkill(i, "L2TPNS Closing");
-               }
-               for (i = 1; i < MAXTUNNEL; i++)
-               {
-                       if (tunnel[i].ip || tunnel[i].state)
-                               tunnelshutdown(i, "L2TPNS Closing");
-               }
-       }
-
-       main_quit++;
+       main_quit = (sig == SIGQUIT) ? QUIT_SHUTDOWN : QUIT_FAILOVER;
 }
 
 static void sigchild_handler(int sig)
@@ -3373,188 +4502,12 @@ 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)
+static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response)
 {
        MD5_CTX ctx;
        *challenge_response = NULL;
 
-       if (!*config->l2tpsecret)
+       if (!*config->l2tp_secret)
        {
                LOG(0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
                return;
@@ -3562,13 +4515,13 @@ static void build_chap_response(char *challenge, uint8_t id, uint16_t challenge_
 
        LOG(4, 0, 0, "   Building challenge response for CHAP request\n");
 
-       *challenge_response = (char *)calloc(17, 1);
+       *challenge_response = calloc(17, 1);
 
-       MD5Init(&ctx);
-       MD5Update(&ctx, &id, 1);
-       MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
-       MD5Update(&ctx, challenge, challenge_length);
-       MD5Final(*challenge_response, &ctx);
+       MD5_Init(&ctx);
+       MD5_Update(&ctx, &id, 1);
+       MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
+       MD5_Update(&ctx, challenge, challenge_length);
+       MD5_Final(*challenge_response, &ctx);
 
        return;
 }
@@ -3596,7 +4549,9 @@ static void update_config()
        syslog_log = 0;
        if (log_stream)
        {
-               fclose(log_stream);
+               if (log_stream != stderr)
+                       fclose(log_stream);
+
                log_stream = NULL;
        }
 
@@ -3631,6 +4586,20 @@ static void update_config()
                setbuf(log_stream, NULL);
        }
 
+#define L2TP_HDRS              (20+8+6+4)      // L2TP data encaptulation: ip + udp + l2tp (data) + ppp (inc hdlc)
+#define TCP_HDRS               (20+20)         // TCP encapsulation: ip + tcp
+
+       if (config->l2tp_mtu <= 0)              config->l2tp_mtu = 1500; // ethernet default
+       else if (config->l2tp_mtu < MINMTU)     config->l2tp_mtu = MINMTU;
+       else if (config->l2tp_mtu > MAXMTU)     config->l2tp_mtu = MAXMTU;
+
+       // reset MRU/MSS globals
+       MRU = config->l2tp_mtu - L2TP_HDRS;
+       if (MRU > PPPoE_MRU)
+               MRU = PPPoE_MRU;
+
+       MSS = MRU - TCP_HDRS;
+
        // Update radius
        config->numradiusservers = 0;
        for (i = 0; i < MAXRADSERVER; i++)
@@ -3644,7 +4613,7 @@ 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;
@@ -3653,12 +4622,10 @@ 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;
@@ -3678,11 +4645,13 @@ 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)
@@ -3705,6 +4674,9 @@ static void update_config()
                        strcat(config->radius_authtypes_s, ", pap");
        }
 
+       if (!config->radius_dae_port)
+               config->radius_dae_port = DAEPORT;
+
        // re-initialise the random number source
        initrandom(config->random_device);
 
@@ -3727,7 +4699,6 @@ 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)
@@ -3774,8 +4745,6 @@ static void update_config()
                        LOG(0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
                }
        }
-
-       config->reload_config = 0;
 }
 
 static void read_config_file()
@@ -3793,10 +4762,9 @@ static void read_config_file()
        cli_do_file(f);
        LOG(3, 0, 0, "Done reading config file\n");
        fclose(f);
-       update_config();
 }
 
-int sessionsetup(tunnelidt t, sessionidt s)
+int sessionsetup(sessionidt s, tunnelidt t)
 {
        // A session now exists, set it up
        in_addr_t ip;
@@ -3808,13 +4776,13 @@ 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.", CDN_TRY_ANOTHER, TERM_SERVICE_UNAVAILABLE);
                        return 0;
                }
                LOG(3, s, t, "   No IP allocated.  Assigned %s from pool\n",
@@ -3825,6 +4793,14 @@ int sessionsetup(tunnelidt t, sessionidt s)
        // Make sure this is right
        session[s].tunnel = t;
 
+       // Join a bundle if the MRRU option is accepted
+       if (session[s].mrru > 0 && !session[s].bundle)
+       {
+               LOG(3, s, t, "This session can be part of multilink bundle\n");
+               if (join_bundle(s))
+                       cluster_send_bundle(session[s].bundle);
+       }
+
        // zap old sessions with same IP and/or username
        // Don't kill gardened sessions - doing so leads to a DoS
        // from someone who doesn't need to know the password
@@ -3834,8 +4810,29 @@ 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;
+
+                       // Allow duplicate sessions for guest account.
+                       if (*config->guest_user && !strcasecmp(user, config->guest_user))
+                               continue;
+
+                       // Allow duplicate sessions for multilink ones of the same bundle.
+                       if (session[s].bundle && session[i].bundle && session[s].bundle == session[i].bundle)
+                               continue;
+
+                       // Drop the new session in case of duplicate sessionss, not the old one.
+                       if (!strcasecmp(user, session[i].user))
                                sessionkill(i, "Duplicate session for users");
                }
        }
@@ -3857,6 +4854,7 @@ 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);
@@ -3865,13 +4863,8 @@ int sessionsetup(tunnelidt t, sessionidt s)
                        cache_ipmap(session[s].ip, s);
        }
 
-       if (!session[s].unique_id)
-       {
-               // did this session just finish radius?
-               LOG(3, s, t, "Sending initial IPCP to client\n");
-               sendipcp(t, s);
-               session[s].unique_id = ++last_id;
-       }
+       sess_local[s].lcp_authtype = 0; // RADIUS authentication complete
+       lcp_open(s, t); // transition to Network phase and send initial IPCP
 
        // Run the plugin's against this new session.
        {
@@ -3979,6 +4972,10 @@ int load_session(sessionidt s, sessiont *new)
                }
        }
 
+       // check v6 routing
+       if (new->ipv6prefixlen && new->ppp.ipv6cp == Opened && session[s].ppp.ipv6cp != Opened)
+                   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]))
        {
@@ -4008,12 +5005,6 @@ int load_session(sessionidt s, sessiont *new)
                                        // for walking the sessions to forward byte counts to the master.
                config->cluster_highest_sessionid = s;
 
-       // TEMP: old session struct used a uint32_t to define the throttle
-       // speed for both up/down, new uses a uint16_t for each.  Deal with
-       // sessions from an old master for migration.
-       if (new->throttle_out == 0 && new->tbf_out)
-               new->throttle_out = new->throttle_in;
-
        memcpy(&session[s], new, sizeof(session[s]));   // Copy over..
 
                // Do fixups into address pool.
@@ -4077,6 +5068,7 @@ static int add_plugin(char *plugin_name)
                radiusnew,
                radiussend,
                getconfig,
+               sessionshutdown,
                sessionkill,
                throttle_session,
                cluster_send_session,
@@ -4198,7 +5190,7 @@ static void plugins_done()
                run_plugin_done(p);
 }
 
-static void processcontrol(uint8_t * buf, int len, struct sockaddr_in *addr, int alen)
+static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen, struct in_addr *local)
 {
        struct nsctl request;
        struct nsctl response;
@@ -4356,7 +5348,7 @@ static void processcontrol(uint8_t * buf, int len, struct sockaddr_in *addr, int
        r = pack_control(buf, NSCTL_MAX_PKT_SZ, response.type, response.argc, response.argv);
        if (r > 0)
        {
-               sendto(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen);
+               sendtofrom(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen, local);
                if (log_stream && config->debug >= 4)
                {
                        LOG(4, 0, 0, "Sent [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
@@ -4397,6 +5389,9 @@ 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
@@ -4406,7 +5401,7 @@ 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]);
@@ -4415,11 +5410,14 @@ 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);
        }
 }
 
@@ -4438,7 +5436,7 @@ 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;
@@ -4476,7 +5474,7 @@ 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;
@@ -4503,75 +5501,70 @@ 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;
+       uint16_t m = htons(type);
 
        // Compute initial pad
-       MD5Init(&ctx);
-       MD5Update(&ctx, type, 2);
-       MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
-       MD5Update(&ctx, session[s].random_vector, session[s].random_vector_length);
-       MD5Final(digest, &ctx);
+       MD5_Init(&ctx);
+       MD5_Update(&ctx, (unsigned char *) &m, 2);
+       MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
+       MD5_Update(&ctx, vector, vec_len);
+       MD5_Final(digest, &ctx);
 
-       // Get hidden length
-       hidden_length = ((uint16_t) (digest[0] ^ cursor[0])) * 256 + (uint16_t) (digest[1] ^ cursor[1]);
+       // pointer to last decoded 16 octets
+       last = value;
 
-       // Keep these for later use
-       working_vector[0] = *cursor;
-       working_vector[1] = *(cursor + 1);
-       cursor += 2;
-
-       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;
+               // calculate a new pad based on the last decoded block
+               if (d >= sizeof(digest))
+               {
+                       MD5_Init(&ctx);
+                       MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
+                       MD5_Update(&ctx, last, sizeof(digest));
+                       MD5_Final(digest, &ctx);
+
+                       d = 0;
+                       last = value;
+               }
+
+               *value++ ^= digest[d++];
+               len--;
        }
+}
+
+int find_filter(char const *name, size_t len)
+{
+       int free = -1;
+       int i;
 
-       /* Decrypt remainder */
-       done = 2;
-       todo = hidden_length;
-       while (todo)
+       for (i = 0; i < MAXFILTER; i++)
        {
-               working_vector[done] = *cursor;
-               *output = digest[done] ^ *cursor;
-               ++output;
-               ++cursor;
-               --todo;
-               ++done;
-               if (done == 16 && todo)
+               if (!*ip_filters[i].name)
                {
-                       // Compute new digest
-                       done = 0;
-                       MD5Init(&ctx);
-                       MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
-                       MD5Update(&ctx, &working_vector, 16);
-                       MD5Final(digest, &ctx);
+                       if (free < 0)
+                               free = i;
+
+                       continue;
                }
-       }
 
-       return hidden_length + 6;
+               if (strlen(ip_filters[i].name) != len)
+                       continue;
+
+               if (!strncmp(ip_filters[i].name, name, len))
+                       return i;
+       }
+                       
+       return free;
 }
 
 static int ip_filter_port(ip_filter_portt *p, uint16_t port)
@@ -4659,7 +5652,9 @@ int ip_filter(uint8_t *buf, int len, uint8_t filter)
 
                if (frag_offset)
                {
-                       if (!rule->frag || rule->action == FILTER_ACTION_DENY)
+                       // layer 4 deny rules are skipped
+                       if (rule->action == FILTER_ACTION_DENY &&
+                           (rule->src_ports.op || rule->dst_ports.op || rule->tcp_flag_op))
                                continue;
                }
                else