Use multiple radius sockets to allow more concurrent authentication requests
[l2tpns.git] / l2tpns.c
index ea21dda..8fc2167 100644 (file)
--- a/l2tpns.c
+++ b/l2tpns.c
@@ -8,6 +8,8 @@
 #include <errno.h>
 #include <fcntl.h>
 #include <linux/if_tun.h>
+#define SYSLOG_NAMES
+#include <syslog.h>
 #include <malloc.h>
 #include <math.h>
 #include <net/route.h>
@@ -18,6 +20,7 @@
 #include <stdarg.h>
 #include <stdlib.h>
 #include <stdio.h>
+#define __USE_GNU
 #include <string.h>
 #include <sys/ioctl.h>
 #include <sys/socket.h>
 #include <sys/types.h>
 #include <sys/wait.h>
 #include <linux/if.h>
+#include <stddef.h>
 #include <time.h>
 #include <dlfcn.h>
 #include <unistd.h>
-#ifdef HAVE_LIBCLI
-#include <libcli.h>
-#endif
 #include "md5.h"
 #include "l2tpns.h"
 #include "cluster.h"
 #include "control.h"
 #include "util.h"
 
-ipt radiusserver[MAXRADSERVER]; // radius servers
-u8 numradiusservers = 0;  // how many radius servers
-
 // Globals
-char tapdevice[10] = "";    // tap device name
-int tapfd = -1;            // tap interface file handle
-int udpfd = -1;            // UDP file handle
-int controlfd = -1;        // Control signal handle
-int snoopfd = -1;          // UDP file handle for sending out intercept data
-int radfd = -1;            // RADIUS requests file handle
-int ifrfd = -1;            // File descriptor for routing, etc
-char debug = 0;                // debug leveL
-time_t basetime = 0;          // base clock
-char hostname[1000] = ""; // us.
-ipt myip = 0;              // MY IP
-u16 tapmac[3];             // MAC of tap interface
-int tapidx;               // ifr_ifindex of tap device
-char *radiussecret = 0;      // RADIUS secret
-char *l2tpsecret = 0;        // L2TP secret
-u32 sessionid = 0;         // session id for radius accounting
-char   *snoop_destination_host = NULL;
-u16    snoop_destination_port = 0;
-char *log_filename = NULL;
-char *config_file = CONFIGFILE;
+struct configt *config = NULL; // all configuration
+int tapfd = -1;                        // tap interface file handle
+int udpfd = -1;                        // UDP file handle
+int controlfd = -1;            // Control signal handle
+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
+time_t basetime = 0;           // base clock
+char hostname[1000] = "";      // us.
+ipt myip = 0;                  // MY IP
+u16 tapmac[3];                 // MAC of tap interface
+int tapidx;                    // ifr_ifindex of tap device
+u32 sessionid = 0;             // session id for radius accounting
+int syslog_log = 0;            // are we logging to syslog
 FILE *log_stream = NULL;
-unsigned long default_dns1 = 0, default_dns2 = 0;
 struct sockaddr_in snoop_addr = {0};
-extern unsigned long rl_rate;
 extern int cluster_sockfd;
 unsigned long last_sid = 0;
-int config_save_state = 0;
-int radius_accounting = 0;
-char *accounting_dir = NULL;
-uint32_t cluster_address = 0;
-uint32_t bind_address = INADDR_ANY;
-int handle_interface = 0;
-#ifdef HAVE_LIBCLI
-pid_t cli_pid = 0;
 int clifd = 0;
 sessionidt *cli_session_kill = NULL;
 tunnelidt *cli_tunnel_kill = NULL;
-#endif
 static void *ip_hash[256];
 unsigned long udp_tx = 0, udp_rx = 0, udp_rx_pkt = 0;
 unsigned long eth_tx = 0, eth_rx = 0, eth_rx_pkt = 0;
-unsigned int ip_pool_index = 0;
 unsigned int ip_pool_size = 0;
 time_t time_now;
 char time_now_string[64] = {0};
 char main_quit = 0;
-int dump_speed = 0;
-int target_uid = 500;
 char *_program_name = NULL;
 linked_list *loaded_plugins;
 linked_list *plugins[MAX_PLUGIN_TYPES];
 
+#define membersize(STRUCT, MEMBER) sizeof(((STRUCT *)0)->MEMBER)
+#define CONFIG(NAME, MEMBER, TYPE) { NAME, offsetof(struct configt, MEMBER), membersize(struct configt, MEMBER), TYPE }
+
+struct config_descriptt config_values[] = {
+       CONFIG("debug", debug, INT),
+       CONFIG("log_file", log_filename, STRING),
+       CONFIG("l2tp_secret", l2tpsecret, STRING),
+       CONFIG("primary_dns", default_dns1, IP),
+       CONFIG("secondary_dns", default_dns2, IP),
+       CONFIG("save_state", save_state, BOOL),
+       CONFIG("snoop_host", snoop_destination_host, IP),
+       CONFIG("snoop_port", snoop_destination_port, SHORT),
+       CONFIG("primary_radius", radiusserver[0], IP),
+       CONFIG("secondary_radius", radiusserver[1], IP),
+       CONFIG("radius_accounting", radius_accounting, BOOL),
+       CONFIG("radius_secret", radiussecret, STRING),
+       CONFIG("bind_address", bind_address, IP),
+       CONFIG("cluster_master", cluster_address, IP),
+       CONFIG("throttle_speed", rl_rate, UNSIGNED_LONG),
+       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),
+       { NULL, 0, 0, 0 },
+};
+
 char *plugin_functions[] = {
        NULL,
        "plugin_pre_auth",
@@ -105,7 +110,6 @@ char *plugin_functions[] = {
        "plugin_packet_rx",
        "plugin_packet_tx",
        "plugin_timer",
-       "plugin_config",
        "plugin_new_session",
        "plugin_kill_session",
        "plugin_control",
@@ -113,13 +117,10 @@ char *plugin_functions[] = {
 };
 #define max_plugin_functions (sizeof(plugin_functions) / sizeof(char *))
 
-tunnelt *tunnel = NULL;        // 1000 * 45 = 45000 = 45k
+tunnelt *tunnel = NULL;                // 1000 * 45 = 45000 = 45k
 sessiont *session = NULL;      // 5000 * 213 = 1065000 = 1 Mb
 radiust *radius = NULL;
 ippoolt *ip_address_pool = NULL;
-tunnelidt tunnelfree;           // free list link heads
-sessionidt sessionfree = 0;
-u8 radiusfree;
 controlt *controlfree = 0;
 struct Tstats *_statistics = NULL;
 #ifdef RINGBUFFER
@@ -132,10 +133,12 @@ void sighup_handler(int);
 void sigterm_handler(int);
 void sigquit_handler(int);
 void sigchild_handler(int);
-void sigsegv_handler(int);
 void read_config_file();
 void read_state();
 void dump_state();
+void tunnel_clean();
+tunnelidt new_tunnel();
+void update_config();
 
 // return internal time (10ths since run)
 clockt now(void)
@@ -154,6 +157,8 @@ clockt backoff(u8 try)
 
 void _log(int level, ipt address, sessionidt s, tunnelidt t, const char *format, ...)
 {
+       static char message[65535] = {0};
+       static char message2[65535] = {0};
        va_list ap;
 
 #ifdef RINGBUFFER
@@ -175,68 +180,73 @@ void _log(int level, ipt address, sessionidt s, tunnelidt t, const char *format,
        }
 #endif
 
-       if (debug < level) return;
+       if (config->debug < level) return;
 
-       if (!log_stream && log_filename)
+       va_start(ap, format);
+       if (log_stream)
        {
-               if ((log_stream = fopen(log_filename, "a")))
-               fseek(log_stream, 0, SEEK_END);
-               setbuf(log_stream, NULL);
+               vsnprintf(message2, 65535, format, ap);
+               snprintf(message, 65535, "%s %02d/%02d %s", time_now_string, t, s, message2);
+               fprintf(log_stream, message);
        }
-       if (!log_stream)
+       else if (syslog_log)
        {
-               log_stream = stderr;
-               setbuf(log_stream, NULL);
+               vsnprintf(message2, 65535, format, ap);
+               snprintf(message, 65535, "%02d/%02d %s", t, s, message2);
+               syslog(level + 2, message); // We don't need LOG_EMERG or LOG_ALERT
        }
-
-       va_start(ap, format);
-       fprintf(log_stream, "%s %02d/%02d ", time_now_string, t, s);
-       vfprintf(log_stream, format, ap);
        va_end(ap);
 }
 
 void _log_hex(int level, ipt address, sessionidt s, tunnelidt t, const char *title, const char *data, int maxsize)
 {
-       unsigned int i, j;
+       int i, j;
        unsigned const char *d = (unsigned const char *)data;
 
-       if (debug < level) return;
-       log(level, address, s, t, "%s (%d bytes):\n", title, maxsize);
-       setvbuf(log_stream, NULL, _IOFBF, 16384);
-       for (i = 0; i < maxsize; )
+       if (config->debug < level) return;
+
+       // No support for log_hex to syslog
+       if (log_stream)
        {
-               fprintf(log_stream, "%4X: ", i);
-               for (j = i; j < maxsize && j < (i + 16); j++)
-               {
-                       fprintf(log_stream, "%02X ", d[j]);
-                       if (j == i + 7)
-                               fputs(": ", log_stream);
-               }
+               log(level, address, s, t, "%s (%d bytes):\n", title, maxsize);
+               setvbuf(log_stream, NULL, _IOFBF, 16384);
 
-               for (; j < i + 16; j++)
+               for (i = 0; i < maxsize; )
                {
-                       fputs("   ", log_stream);
-                       if (j == i + 7)
-                               fputs(": ", log_stream);
-               }
+                       fprintf(log_stream, "%4X: ", i);
+                       for (j = i; j < maxsize && j < (i + 16); j++)
+                       {
+                               fprintf(log_stream, "%02X ", d[j]);
+                               if (j == i + 7)
+                                       fputs(": ", log_stream);
+                       }
 
-               fputs("  ", log_stream);
-               for (j = i; j < maxsize && j < (i + 16); j++)
-               {
-                       if (d[j] >= 0x20 && d[j] < 0x7f && d[j] != 0x20)
-                               fputc(d[j], log_stream);
-                       else
-                               fputc('.', log_stream);
+                       for (; j < i + 16; j++)
+                       {
+                               fputs("   ", log_stream);
+                               if (j == i + 7)
+                                       fputs(": ", log_stream);
+                       }
 
-                       if (j == i + 7)
-                               fputs("  ", log_stream);
+                       fputs("  ", log_stream);
+                       for (j = i; j < maxsize && j < (i + 16); j++)
+                       {
+                               if (d[j] >= 0x20 && d[j] < 0x7f && d[j] != 0x20)
+                                       fputc(d[j], log_stream);
+                               else
+                                       fputc('.', log_stream);
+
+                               if (j == i + 7)
+                                       fputs("  ", log_stream);
+                       }
+
+                       i = j;
+                       fputs("\n", log_stream);
                }
 
-               i = j;
-               fputs("\n", log_stream);
+               fflush(log_stream);
+               setbuf(log_stream, NULL);
        }
-       fflush(log_stream);
-       setbuf(log_stream, NULL);
 }
 
 
@@ -245,13 +255,13 @@ void routeset(ipt ip, ipt mask, ipt gw, u8 add)
 {
        struct rtentry r;
        memset(&r, 0, sizeof(r));
-       r.rt_dev = tapdevice;
+       r.rt_dev = config->tapdevice;
        r.rt_dst.sa_family = AF_INET;
        *(u32 *) & (((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr) = htonl(ip);
        r.rt_gateway.sa_family = AF_INET;
        *(u32 *) & (((struct sockaddr_in *) &r.rt_gateway)->sin_addr.s_addr) = htonl(gw);
        r.rt_genmask.sa_family = AF_INET;
-       *(u32 *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask ? : 0xFFFFFFF);
+       *(u32 *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask ? mask : 0xFFFFFFF);
        r.rt_flags = (RTF_UP | RTF_STATIC);
        if (gw)
                r.rt_flags |= RTF_GATEWAY;
@@ -275,17 +285,21 @@ void inittap(void)
                log(0, 0, 0, 0, "Can't open %s: %s\n", TAPDEVICE, strerror(errno));
                exit(-1);
        }
+       {
+               int flags = fcntl(tapfd, F_GETFL, 0);
+               fcntl(tapfd, F_SETFL, flags | O_NONBLOCK);
+       }
        if (ioctl(tapfd, TUNSETIFF, (void *) &ifr) < 0)
        {
                log(0, 0, 0, 0, "Can't set tap interface: %s\n", strerror(errno));
                exit(-1);
        }
-       assert(strlen(ifr.ifr_name) < sizeof(tapdevice));
-       strcpy(tapdevice, ifr.ifr_name);
+       assert(strlen(ifr.ifr_name) < sizeof(config->tapdevice));
+       strncpy(config->tapdevice, ifr.ifr_name, sizeof(config->tapdevice) - 1);
        ifrfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
 
        sin.sin_family = AF_INET;
-       sin.sin_addr.s_addr = handle_interface ? bind_address : 0x01010101; // 1.1.1.1
+       sin.sin_addr.s_addr = config->bind_address ? config->bind_address : 0x01010101; // 1.1.1.1
        memcpy(&ifr.ifr_addr, &sin, sizeof(struct sockaddr));
 
        if (ioctl(ifrfd, SIOCSIFADDR, (void *) &ifr) < 0)
@@ -293,6 +307,13 @@ void inittap(void)
                perror("set tap addr");
                exit( -1);
        }
+       /* Bump up the qlen to deal with bursts from the network */
+       ifr.ifr_qlen = 1000;
+       if (ioctl(ifrfd, SIOCSIFTXQLEN, (void *) &ifr) < 0)
+       {
+               perror("set tap qlen");
+               exit( -1);
+       }
        ifr.ifr_flags = IFF_UP;
        if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0)
        {
@@ -323,12 +344,16 @@ void initudp(void)
        memset(&addr, 0, sizeof(addr));
        addr.sin_family = AF_INET;
        addr.sin_port = htons(L2TPPORT);
-       addr.sin_addr.s_addr = bind_address;
+       addr.sin_addr.s_addr = config->bind_address;
        udpfd = socket(AF_INET, SOCK_DGRAM, UDP);
        setsockopt(udpfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
+       {
+               int flags = fcntl(udpfd, F_GETFL, 0);
+               fcntl(udpfd, F_SETFL, flags | O_NONBLOCK);
+       }
        if (bind(udpfd, (void *) &addr, sizeof(addr)) < 0)
        {
-               perror("bind");
+               perror("udp bind");
                exit( -1);
        }
        snoopfd = socket(AF_INET, SOCK_DGRAM, UDP);
@@ -349,8 +374,9 @@ void initudp(void)
 // Find session by IP, 0 for not found
 sessionidt sessionbyip(ipt ip)
 {
-       unsigned char *a = (char *)&ip;
+       unsigned char *a = (unsigned char *)&ip;
        char **d = (char **) ip_hash;
+       sessionidt s;
 
 #ifdef STAT_CALLS
        STAT(call_sessionbyip);
@@ -360,12 +386,15 @@ sessionidt sessionbyip(ipt ip)
        if (!(d = (char **) d[(size_t) *a++])) return 0;
        if (!(d = (char **) d[(size_t) *a++])) return 0;
 
-       return (ipt) d[(size_t) *a];
+       s = (ipt) d[(size_t) *a];
+       if (s && session[s].tunnel)
+               return s;
+       return 0;
 }
 
 void cache_sessionid(ipt ip, sessionidt s)
 {
-       unsigned char *a = (char *) &ip;
+       unsigned char *a = (unsigned char *) &ip;
        char **d = (char **) ip_hash;
        int i;
 
@@ -386,7 +415,7 @@ void cache_sessionid(ipt ip, sessionidt s)
 
 void uncache_sessionid(ipt ip)
 {
-       unsigned char *a = (char *) &ip;
+       unsigned char *a = (unsigned char *) &ip;
        char **d = (char **) ip_hash;
        int i;
 
@@ -399,7 +428,7 @@ void uncache_sessionid(ipt ip)
 }
 
 // Find session by username, 0 for not found
-// walled garden'd users aren't authenticated, so the username is
+// walled garden users aren't authenticated, so the username is
 // reasonably useless. Ignore them to avoid incorrect actions
 sessionidt sessionbyuser(char *username)
 {
@@ -415,31 +444,33 @@ sessionidt sessionbyuser(char *username)
 
 void send_garp(ipt ip)
 {
-    int s;
-    struct ifreq ifr;
-    unsigned char mac[6];
+       int s;
+       struct ifreq ifr;
+       unsigned char mac[6];
 
-    s = socket(PF_INET, SOCK_DGRAM, 0);
-    if (s < 0)
-    {
-      perror("socket");
-      exit(-1);
-    }
-    memset(&ifr, 0, sizeof(ifr));
-    strcpy(ifr.ifr_name, "eth0");
-    if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
-    {
-      perror("get eth0 hwaddr");
-      exit(-1);
-    }
-    memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
-    if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
-    {
-      perror("get eth0 ifindex");
-      exit(-1);
-    }
-    close(s);
-    sendarp(ifr.ifr_ifindex, mac, ip);
+       s = socket(PF_INET, SOCK_DGRAM, 0);
+       if (s < 0)
+       {
+               log(0, 0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
+               return;
+       }
+       memset(&ifr, 0, sizeof(ifr));
+       strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
+       if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
+       {
+               log(0, 0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
+               close(s);
+               return;
+       }
+       memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
+       if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
+       {
+               log(0, 0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
+               close(s);
+               return;
+       }
+       close(s);
+       sendarp(ifr.ifr_ifindex, mac, ip);
 }
 
 // Find session by username, 0 for not found
@@ -527,7 +558,7 @@ void processarp(u8 * buf, int len)
        s = sessionbyip(htonl(ip));
        if (s)
        {
-               log(3, ip, s, session[s].tunnel, "ARP reply for %u.%u.%u.%u\n", ip >> 24, ip >> 16 & 255, ip >> 8 & 255, ip & 255, session[s].tunnel, s);
+               log(3, ip, s, session[s].tunnel, "ARP reply for %u.%u.%u.%u\n", ip >> 24, ip >> 16 & 255, ip >> 8 & 255, ip & 255);
                memcpy(buf + 4, buf + 10, 6); // set destination as source
                *(u16 *) (buf + 10) = htons(tapmac[0]); // set soucre address
                *(u16 *) (buf + 12) = htons(tapmac[1]);
@@ -555,9 +586,20 @@ void tunnelsend(u8 * buf, u16 l, tunnelidt t)
 #ifdef STAT_CALLS
        STAT(call_tunnelsend);
 #endif
+       if (!t)
+       {
+               static int backtrace_count = 0;
+               log(0, 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, 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;
        }
@@ -605,7 +647,7 @@ void processipout(u8 * buf, int len)
 #ifdef STAT_CALLS
        STAT(call_processipout);
 #endif
-       if (len < 38)
+       if (len < MIN_IP_SIZE)
        {
                log(1, 0, 0, 0, "Short IP, %d bytes\n", len);
                STAT(tunnel_tx_errors);
@@ -626,7 +668,8 @@ void processipout(u8 * buf, int len)
        ip = *(u32 *)(buf + 16);
        if (!(s = sessionbyip(ip)))
        {
-//             log(4, 0, 0, 0, "IP: Can't find session for IP %s\n", inet_toa(ip));
+               log(4, 0, 0, 0, "IP: Sending ICMP host unreachable to %s\n", inet_toa(*(u32 *)(buf + 12)));
+               host_unreachable(*(u32 *)(buf + 12), *(u16 *)(buf + 4), ip, buf, (len < 64) ? 64 : len);
                return;
        }
        t = session[s].tunnel;
@@ -637,17 +680,12 @@ void processipout(u8 * buf, int len)
 
        log(5, session[s].ip, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
 
-       // Plugin hook
-       {
-               struct param_packet_rx packet = { &tunnel[t], &session[s], buf, len };
-               run_plugins(PLUGIN_PACKET_RX, &packet);
-       }
-
        // Add on L2TP header
        {
                u8 *p = makeppp(b, buf, len, t, s, PPPIP);
                tunnelsend(b, len + (p-b), t); // send it...
                sp->cout += len; // byte count
+               sp->total_cout += len; // byte count
                sp->pout++;
                udp_tx += len;
        }
@@ -764,7 +802,10 @@ void sessionshutdown(sessionidt s, char *reason)
        STAT(call_sessionshutdown);
 #endif
        if (!session[s].tunnel)
+       {
+               log(3, session[s].ip, s, session[s].tunnel, "Called sessionshutdown on a session with no tunnel.\n");
                return;                   // not a live session
+       }
 
        if (!session[s].die)
                log(2, 0, s, session[s].tunnel, "Shutting down session %d: %s\n", s, reason);
@@ -778,16 +819,17 @@ void sessionshutdown(sessionidt s, char *reason)
 
        // RADIUS Stop message
        if (session[s].opened && !walled_garden && !dead) {
-               u8 r = session[s].radius;
+               u16 r = session[s].radius;
                if (!r)
                {
-                       if (!radiusfree)
+                       if (!(r = radiusnew(s)))
                        {
                                log(1, 0, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
                                STAT(radius_overflow);
-                       } else {
+                       }
+                       else
+                       {
                                int n;
-                               r = radiusnew(s);
                                for (n = 0; n < 15; n++)
                                        radius[r].auth[n] = rand();
                        }
@@ -798,7 +840,7 @@ void sessionshutdown(sessionidt s, char *reason)
 
        if (session[s].ip)
        {                          // IP allocated, clear and unroute
-               u8 r;
+               u16 r;
                if (session[s].route[0].ip)
                {
                        routeset(session[s].ip, 0, 0, 0);
@@ -812,8 +854,7 @@ void sessionshutdown(sessionidt s, char *reason)
                        }
                }
                if (session[s].throttle) throttle_session(s, 0); session[s].throttle = 0;
-               free_ip_address(session[s].ip);
-               session[s].ip = 0;
+               free_ip_address(s);
        }
        {                            // Send CDN
                controlt *c = controlnew(14); // sending CDN
@@ -827,7 +868,7 @@ void sessionshutdown(sessionidt s, char *reason)
 void sendipcp(tunnelidt t, sessionidt s)
 {
        u8 buf[MAXCONTROL];
-       u8 r = session[s].radius;
+       u16 r = session[s].radius;
        u8 *q;
 #ifdef STAT_CALLS
        STAT(call_sendipcp);
@@ -847,11 +888,11 @@ void sendipcp(tunnelidt t, sessionidt s)
        }
        q = makeppp(buf, 0, 0, t, s, PPPIPCP);
        *q = ConfigReq;
-       q[1] = r;                    // ID, dont care, we only send one type of request
+       q[1] = r << RADIUS_SHIFT;                    // ID, dont care, we only send one type of request
        *(u16 *) (q + 2) = htons(10);
        q[4] = 3;
        q[5] = 6;
-       *(u32 *) (q + 6) = htonl(myip ? : session[s].ip); // send my IP (use theirs if I dont have one)
+       *(u32 *) (q + 6) = htonl(myip ? myip : session[s].ip); // send my IP (use theirs if I dont have one)
        tunnelsend(buf, 10 + (q - buf), t); // send it
 }
 
@@ -863,11 +904,11 @@ void sessionkill(sessionidt s, char *reason)
 #endif
        sessionshutdown(s, reason);  // close radius/routes, etc.
        if (session[s].radius)
-               radius[session[s].radius].session = 0; // cant send clean accounting data, session is killed
+               radiusclear(session[s].radius, 0); // cant send clean accounting data, session is killed
+       log(2, 0, s, session[s].tunnel, "Kill session %d: %s\n", s, reason);
        memset(&session[s], 0, sizeof(session[s]));
        session[s].next = sessionfree;
        sessionfree = s;
-       log(2, 0, s, session[s].tunnel, "Kill session %d: %s\n", s, reason);
        cluster_send_session(s);
 }
 
@@ -879,6 +920,9 @@ void tunnelkill(tunnelidt t, char *reason)
 #ifdef STAT_CALLS
        STAT(call_tunnelkill);
 #endif
+
+       tunnel[t].state = TUNNELDIE;
+
        // free control messages
        while ((c = tunnel[t].controls))
        {
@@ -889,34 +933,39 @@ void tunnelkill(tunnelidt t, char *reason)
                controlfree = c;
        }
        // kill sessions
-       for (s = 0; s < MAXSESSION; s++)
+       for (s = 1; s < MAXSESSION; s++)
                if (session[s].tunnel == t)
                        sessionkill(s, reason);
+
        // free tunnel
-       memset(&tunnel[t], 0, sizeof(tunnel[t]));
-       tunnel[t].next = tunnelfree;
+       tunnelclear(t);
        cluster_send_tunnel(t);
        log(1, 0, 0, t, "Kill tunnel %d: %s\n", t, reason);
-       tunnelfree = t;
+       tunnel[t].die = 0;
+       tunnel[t].state = TUNNELFREE;
 }
 
-// shut down a tunnel
+// shut down a tunnel cleanly
 void tunnelshutdown(tunnelidt t, char *reason)
 {
        sessionidt s;
 #ifdef STAT_CALLS
        STAT(call_tunnelshutdown);
 #endif
-       if (!tunnel[t].last || !tunnel[t].far)
-       {                          // never set up, can immediately kill
+       if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
+       {
+               // never set up, can immediately kill
                tunnelkill(t, reason);
                return;
        }
        log(1, 0, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
+
        // close session
-       for (s = 0; s < MAXSESSION; s++)
+       for (s = 1; s < MAXSESSION; s++)
                if (session[s].tunnel == t)
                        sessionkill(s, reason);
+
+       tunnel[t].state = TUNNELDIE;
        tunnel[t].die = now() + 700; // Clean up in 70 seconds
        cluster_send_tunnel(t);
        // TBA - should we wait for sessions to stop?
@@ -1001,7 +1050,6 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
                return;
        }
        l -= (p - buf);
-       if (t) tunnel[t].last = time_now;
        if (*buf & 0x80)
        {                          // control
                u16 message = 0xFFFF; // message type
@@ -1026,41 +1074,25 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
                // if no tunnel specified, assign one
                if (!t)
                {
-                       /*
-                       ipt ip = ntohl(*(ipt *) & addr->sin_addr);
-                       portt port = ntohs(addr->sin_port);
-
-                       // find existing tunnel that was not fully set up
-                       for (t = 0; t < MAXTUNNEL; t++)
-                       {
-                               if ((tunnel[t].ip == ip && tunnel[t].port == port) &&
-                                       (!tunnel[t].die || !tunnel[t].hostname[0]))
-                               {
-                                       char buf[600] = {0};
-                                       snprintf(buf, 600, "Duplicate tunnel with %d. ip=%u port=%d die=%d hostname=%s",
-                                                       t, tunnel[t].ip, tunnel[t].port, tunnel[t].die, tunnel[t].hostname);
-                                       tunnelshutdown(t, buf);
-                                       break;
-                               }
-                       }
-                       */
-
-                       t = tunnelfree;
-                       if (!t)
+                       if (!(t = new_tunnel()))
                        {
                                log(1, ntohl(addr->sin_addr.s_addr), 0, 0, "No more tunnels\n");
                                STAT(tunnel_overflow);
                                return;
                        }
-                       tunnelfree = tunnel[t].next;
-                       memset(&tunnel[t], 0, sizeof(tunnelt));
+                       tunnelclear(t);
                        tunnel[t].ip = ntohl(*(ipt *) & addr->sin_addr);
                        tunnel[t].port = ntohs(addr->sin_port);
                        tunnel[t].window = 4; // default window
                        log(1, ntohl(addr->sin_addr.s_addr), 0, t, "   New tunnel from %u.%u.%u.%u/%u ID %d\n", tunnel[t].ip >> 24, tunnel[t].ip >> 16 & 255, tunnel[t].ip >> 8 & 255, tunnel[t].ip & 255, tunnel[t].port, t);
                        STAT(tunnel_created);
                }
-               {                       // check sequence of this message
+
+               // 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
                        if (tunnel[t].controlc)
                        {                  // some to clear maybe
@@ -1083,12 +1115,12 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 //                             controlnull(t);
                                return;
                        }
-                       if (l)
-                               tunnel[t].nr++;   // receiver advance (do here so quoted correctly in any sends below)
-                       if (skip < 0)
-                               skip = 0;
+                       // receiver advance (do here so quoted correctly in any sends below)
+                       if (l) tunnel[t].nr++;
+                       if (skip < 0) skip = 0;
                        if (skip < tunnel[t].controlc)
-                       {                  // some control packets can now be sent that were previous stuck out of window
+                       {
+                               // some control packets can now be sent that were previous stuck out of window
                                int tosend = tunnel[t].window - skip;
                                controlt *c = tunnel[t].controls;
                                while (c && skip)
@@ -1128,7 +1160,7 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
                                if (flags & 0x40)
                                {
                                        // handle hidden AVPs
-                                       if (!l2tpsecret)
+                                       if (!*config->l2tpsecret)
                                        {
                                                log(1, ntohl(addr->sin_addr.s_addr), s, t, "Hidden AVP requested, but no L2TP secret.\n");
                                                fatal = flags;
@@ -1140,7 +1172,7 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
                                                fatal = flags;
                                                continue;
                                        }
-                                       log(1, ntohl(addr->sin_addr.s_addr), s, t, "Hidden AVP\n");
+                                       log(4, ntohl(addr->sin_addr.s_addr), s, t, "Hidden AVP\n");
                                }
                                if (*b & 0x3C)
                                {
@@ -1193,11 +1225,10 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
                                                }
                                                if (n > 4) {
                                                        /* %*s doesn't work?? */
-                                                       char buf[n-4+2];
-                                                       memcpy(buf, b+4, n-4);
-                                                       buf[n-4+1] = '\0';
+                                                       char *buf = (char *)strndup(b+4, n-4);
                                                        log(4, ntohl(addr->sin_addr.s_addr), s, t, "   Error String: %s\n",
                                                                buf);
+                                                       free(buf);
                                                }
                                                break;
                                        }
@@ -1222,8 +1253,7 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
 //                                     log(4, ntohl(addr->sin_addr.s_addr), s, t, "Bearer capabilities\n");
                                        break;
                                case 5:         // tie breaker
-                                       // We never open tunnels, so we don't
-                                       // care about tie breakers
+                                       // We never open tunnels, so we don't care about tie breakers
 //                                     log(4, ntohl(addr->sin_addr.s_addr), s, t, "Tie breaker\n");
                                        continue;
                                case 6:     // firmware revision
@@ -1293,7 +1323,7 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
                                                memcpy(tmp, b, (n >= 30) ? 30 : n);
                                                session[s].tx_connect_speed = atol(tmp);
                                        }
-                                       log(4, ntohl(addr->sin_addr.s_addr), s, t, "   TX connect speed <%d>\n",
+                                       log(4, ntohl(addr->sin_addr.s_addr), s, t, "   TX connect speed <%lu>\n",
                                                        session[s].tx_connect_speed);
                                        break;
                                case 38:    // rx connect speed
@@ -1308,7 +1338,7 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
                                                memcpy(tmp, b, (n >= 30) ? 30 : n);
                                                session[s].rx_connect_speed = atol(tmp);
                                        }
-                                       log(4, ntohl(addr->sin_addr.s_addr), s, t, "   RX connect speed <%d>\n",
+                                       log(4, ntohl(addr->sin_addr.s_addr), s, t, "   RX connect speed <%lu>\n",
                                                        session[s].rx_connect_speed);
                                        break;
                                case 25:    // Physical Channel ID
@@ -1336,7 +1366,7 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
                                case 31:    // Proxy Authentication Challenge
                                        {
                                                memcpy(radius[session[s].radius].auth, b, 16);
-                                               log(4, ntohl(addr->sin_addr.s_addr), s, t, "   Proxy Auth Challenge (%X)\n", radius[session[s].radius].auth);
+                                               log(4, ntohl(addr->sin_addr.s_addr), s, t, "   Proxy Auth Challenge\n");
                                                break;
                                        }
                                case 32:    // Proxy Authentication ID
@@ -1422,11 +1452,13 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
                                                control16(c, 9, t, 1); // assigned tunnel
                                                controladd(c, t, s); // send the resply
                                        }
+                                       tunnel[t].state = TUNNELOPENING;
                                        break;
                                case 2:       // SCCRP
-                                       // TBA
+                                       tunnel[t].state = TUNNELOPEN;
                                        break;
                                case 3:       // SCCN
+                                       tunnel[t].state = TUNNELOPEN;
                                        controlnull(t); // ack
                                        break;
                                case 4:       // StopCCN
@@ -1454,42 +1486,38 @@ void processudp(u8 * buf, int len, struct sockaddr_in *addr)
                                        }
                                        else
                                        {
-                                               u8 r;
+                                               u16 r;
                                                controlt *c;
 
+                                               s = sessionfree;
+                                               sessionfree = session[s].next;
+                                               memset(&session[s], 0, sizeof(session[s]));
+
                                                // make a RADIUS session
-                                               if (!radiusfree)
+                                               if (!(r = radiusnew(s)))
                                                {
-                                                       STAT(radius_overflow);
                                                        log(1, ntohl(addr->sin_addr.s_addr), s, t, "No free RADIUS sessions for ICRQ\n");
                                                        return;
                                                }
 
                                                c = controlnew(11); // sending ICRP
-                                               s = sessionfree;
-                                               sessionfree = session[s].next;
-                                               memset(&session[s], 0, sizeof(session[s]));
                                                session[s].id = sessionid++;
                                                session[s].opened = time(NULL);
                                                session[s].tunnel = t;
                                                session[s].far = asession;
+                                               session[s].last_packet = time_now;
                                                log(3, ntohl(addr->sin_addr.s_addr), 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
-                                               r = radiusfree;
-                                               radiusfree = radius[r].next;
-                                               memset(&radius[r], 0, sizeof(radius[r]));
-                                               session[s].radius = r;
-                                               radius[r].session = s;
                                                {
                                                        // Generate a random challenge
                                                        int n;
                                                        for (n = 0; n < 15; n++)
                                                                radius[r].auth[n] = rand();
                                                }
-                                               strcpy(radius[r].calling, calling);
-                                               strcpy(session[s].called, called);
-                                               strcpy(session[s].calling, calling);
+                                               strncpy(radius[r].calling, calling, sizeof(radius[r].calling) - 1);
+                                               strncpy(session[s].called, called, sizeof(session[s].called) - 1);
+                                               strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
                                                STAT(session_created);
                                        }
                                        break;
@@ -1617,51 +1645,57 @@ void processtap(u8 * buf, int len)
        }
        if (*(u16 *) (buf + 2) == htons(PKTARP)) // ARP
                processarp(buf, len);
-       else if (*(u16 *) (buf + 2) == htons(PKTIP)) // ARP
+       else if (*(u16 *) (buf + 2) == htons(PKTIP)) // IP
                processipout(buf, len);
-       else
-       {
-               log(1, 0, 0, 0, "Unexpected tap packet %04X, %d bytes\n", ntohs(*(u16 *) (buf + 2)), len);
-       }
 }
 
 // main loop - gets packets on tap or udp and processes them
 void mainloop(void)
 {
        fd_set cr;
-       int cn;
+       int cn, i;
        u8 buf[65536];
        struct timeval to;
+
        clockt slow = now();       // occasional functions like session/tunnel expiry, tunnel hello, etc
        clockt next_acct = slow + ACCT_TIME;
        clockt next_cluster_ping = slow + 50;
+       clockt next_clean = time_now + config->cleanup_interval;
        to.tv_sec = 1;
        to.tv_usec = 0;
-       log(4, 0, 0, 0, "Beginning of main loop. udpfd=%d, tapfd=%d, radfd=%d, cluster_sockfd=%d, controlfd=%d\n",
-                       udpfd, tapfd, radfd, cluster_sockfd, controlfd);
+       log(4, 0, 0, 0, "Beginning of main loop. udpfd=%d, tapfd=%d, cluster_sockfd=%d, controlfd=%d\n",
+                       udpfd, tapfd, cluster_sockfd, controlfd);
 
        FD_ZERO(&cr);
        FD_SET(udpfd, &cr);
        FD_SET(tapfd, &cr);
-       FD_SET(radfd, &cr);
        FD_SET(controlfd, &cr);
-#ifdef HAVE_LIBCLI
        FD_SET(clifd, &cr);
-#endif
        if (cluster_sockfd) FD_SET(cluster_sockfd, &cr);
        cn = udpfd;
-       if (cn < radfd) cn = radfd;
        if (cn < tapfd) cn = tapfd;
        if (cn < controlfd) cn = controlfd;
-#ifdef HAVE_LIBCLI
        if (cn < clifd) cn = clifd;
-#endif
        if (cn < cluster_sockfd) cn = cluster_sockfd;
+       for (i = 0; i < config->num_radfds; i++)
+       {
+               if (!radfds[i]) continue;
+               FD_SET(radfds[i], &cr);
+               if (radfds[i] > cn)
+                       cn = radfds[i];
+       }
 
        while (!main_quit)
        {
                fd_set r;
                int n = cn;
+
+               if (config->reload_config)
+               {
+                       // Update the config state based on config settings
+                       update_config();
+               }
+
                memcpy(&r, &cr, sizeof(fd_set));
                n = select(n + 1, &r, 0, 0, &to);
                if (n < 0)
@@ -1677,17 +1711,35 @@ void mainloop(void)
                        struct sockaddr_in addr;
                        int alen = sizeof(addr);
                        if (FD_ISSET(udpfd, &r))
-                               processudp(buf, recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen), &addr);
-                       else if (FD_ISSET(tapfd, &r))
-                               processtap(buf, read(tapfd, buf, sizeof(buf)));
-                       else if (FD_ISSET(radfd, &r))
-                               processrad(buf, recv(radfd, buf, sizeof(buf), 0));
-                       else if (FD_ISSET(cluster_sockfd, &r))
+                       {
+                               int c, n;
+                               for (c = 0; c < config->multi_read_count; c++)
+                               {
+                                       if ((n = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
+                                               processudp(buf, n, &addr);
+                                       else
+                                               break;
+                               }
+                       }
+                       if (FD_ISSET(tapfd, &r))
+                       {
+                               int c, n;
+                               for (c = 0; c < config->multi_read_count; c++)
+                               {
+                                       if ((n = read(tapfd, buf, sizeof(buf))) > 0)
+                                               processtap(buf, n);
+                                       else
+                                               break;
+                               }
+                       }
+                       for (i = 0; i < config->num_radfds; i++)
+                               if (FD_ISSET(radfds[i], &r))
+                                       processrad(buf, recv(radfds[i], buf, sizeof(buf), 0), i);
+                       if (FD_ISSET(cluster_sockfd, &r))
                                processcluster(buf, recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen));
-                       else if (FD_ISSET(controlfd, &r))
+                       if (FD_ISSET(controlfd, &r))
                                processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr);
-#ifdef HAVE_LIBCLI
-                       else if (FD_ISSET(clifd, &r))
+                       if (FD_ISSET(clifd, &r))
                        {
                                struct sockaddr_in addr;
                                int sockfd;
@@ -1704,20 +1756,22 @@ void mainloop(void)
                                        close(sockfd);
                                }
                        }
-#endif
-                       else
-                       {
-                               log(1, 0, 0, 0, "Main select() loop returned %d, but no fds have data waiting\n", n);
-                               continue;
-                       }
                }
-               else if (n == 0) {                       // handle timeouts
+
+               /* 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 (n == 0 || next_clean <= time_now) {
                        clockt when = now();
                        clockt best = when + 100; // default timeout
                        sessionidt s;
                        tunnelidt t;
-                       u8 r;
-                       for (r = 0; r < MAXRADIUS; r++)
+                       int count;
+                       u16 r;
+
+                       log(3, 0, 0, 0, "Begin regular cleanup\n");
+                       for (r = 1; r < MAXRADIUS; r++)
+                       {
                                if (radius[r].state && radius[r].retry)
                                {
                                        if (radius[r].retry <= when)
@@ -1725,7 +1779,10 @@ void mainloop(void)
                                        if (radius[r].retry && radius[r].retry < best)
                                                best = radius[r].retry;
                                }
-                       for (t = 0; t < MAXTUNNEL; t++)
+                               else if (radius[r].state && !radius[r].retry)
+                                       radius[r].retry = backoff(radius[r].try+1);
+                       }
+                       for (t = 1; t < MAXTUNNEL; t++)
                        {
                                // check for expired tunnels
                                if (tunnel[t].die && tunnel[t].die <= when)
@@ -1756,7 +1813,7 @@ void mainloop(void)
                                                best = tunnel[t].retry;
                                }
                                // Send hello
-                               if (tunnel[t].ip && !tunnel[t].die && tunnel[t].last < when + 600 && !tunnel[t].controlc)
+                               if (tunnel[t].state == TUNNELOPEN && tunnel[t].lastrec < when + 600)
                                {
                                        controlt *c = controlnew(6); // sending HELLO
                                        controladd(c, t, 0); // send the message
@@ -1764,7 +1821,6 @@ void mainloop(void)
                                }
                        }
 
-#ifdef HAVE_LIBCLI
                        // Check for sessions that have been killed from the CLI
                        if (cli_session_kill[0])
                        {
@@ -1772,7 +1828,7 @@ void mainloop(void)
                                for (i = 0; i < MAXSESSION && cli_session_kill[i]; i++)
                                {
                                        log(2, 0, cli_session_kill[i], 0, "Dropping session by CLI\n");
-                                       sessionshutdown(cli_session_kill[i], "Requested by CLI");
+                                       sessionshutdown(cli_session_kill[i], "Requested by administrator");
                                        cli_session_kill[i] = 0;
                                }
                        }
@@ -1780,29 +1836,31 @@ void mainloop(void)
                        if (cli_tunnel_kill[0])
                        {
                                int i;
-                               for (i = 0; i < MAXTUNNEL && cli_tunnel_kill[i]; i++)
+                               for (i = 1; i < MAXTUNNEL && cli_tunnel_kill[i]; i++)
                                {
                                        log(2, 0, cli_tunnel_kill[i], 0, "Dropping tunnel by CLI\n");
-                                       tunnelshutdown(cli_tunnel_kill[i], "Requested by CLI");
+                                       tunnelshutdown(cli_tunnel_kill[i], "Requested by administrator");
                                        cli_tunnel_kill[i] = 0;
                                }
                        }
-#endif
 
-                       for (s = 0; s < MAXSESSION; s++)
+                       count = 0;
+                       for (s = 1; s < MAXSESSION; s++)
                        {
                                // check for expired sessions
                                if (session[s].die && session[s].die <= when)
                                {
-                                       STAT(session_timeout);
                                        sessionkill(s, "Expired");
+                                       if (++count >= 1000) break;
                                        continue;
                                }
 
                                // Drop sessions who have not responded within IDLE_TIMEOUT seconds
-                               if (session[s].user[0] && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
+                               if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
                                {
                                        sessionkill(s, "No response to LCP ECHO requests");
+                                       STAT(session_timeout);
+                                       if (++count >= 1000) break;
                                        continue;
                                }
 
@@ -1818,12 +1876,13 @@ void mainloop(void)
                                        *(u32 *)(q + 4) = 0; // Magic Number (not supported)
 
                                        log(4, session[s].ip, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
-                                                       time_now - session[s].last_packet);
+                                                       (int)(time_now - session[s].last_packet));
                                        tunnelsend(b, 24, session[s].tunnel); // send it
+                                       if (++count >= 1000) break;
                                        continue;
                                }
                        }
-                       if (accounting_dir && next_acct <= when)
+                       if (config->accounting_dir && next_acct <= when)
                        {
                                // Dump accounting data
                                next_acct = when + ACCT_TIME;
@@ -1834,14 +1893,15 @@ void mainloop(void)
                        {
                                // Dump accounting data
                                next_cluster_ping = when + 50;
-                               cluster_send_message(cluster_address, bind_address, C_PING, hostname, strlen(hostname));
+                               cluster_send_message(config->cluster_address, config->bind_address, C_PING, hostname, strlen(hostname));
                        }
 
-                       if (best <= when)
-                               best = when + 1;  // should not really happen
-                       to.tv_sec = (best - when) / 10;
-                       to.tv_usec = 100000 * ((best - when) % 10);
-                       log(5, 0, 0, 0, "Next time check in %d.%d seconds\n", (best - when) / 10, ((best - when) % 10));
+                       if (best < when + config->cleanup_interval)
+                               best = when + config->cleanup_interval; // Throttle to at most once per 10 seconds
+                       next_clean = time_now + config->cleanup_interval;
+                       to.tv_sec = config->cleanup_interval;
+                       to.tv_usec = 0;
+                       log(3, 0, 0, 0, "End regular cleanup, next in %d seconds\n", config->cleanup_interval);
                }
        }
 }
@@ -1852,38 +1912,47 @@ void initdata(void)
        int i;
 
        _statistics = mmap(NULL, sizeof(struct Tstats), PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
-       if (_statistics <= 0)
+       if (_statistics == MAP_FAILED)
        {
                log(0, 0, 0, 0, "Error doing mmap for _statistics: %s\n", strerror(errno));
                exit(1);
        }
+       config = mmap(NULL, sizeof(struct configt), PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
+       if (config == MAP_FAILED)
+       {
+               log(0, 0, 0, 0, "Error doing mmap for configuration: %s\n", strerror(errno));
+               exit(1);
+       }
+       memset(config, 0, sizeof(struct configt));
+       time(&config->start_time);
+       strncpy(config->config_file, CONFIGFILE, sizeof(config->config_file) - 1);
        tunnel = mmap(NULL, sizeof(tunnelt) * MAXTUNNEL, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
-       if (tunnel <= 0)
+       if (tunnel == MAP_FAILED)
        {
                log(0, 0, 0, 0, "Error doing mmap for tunnels: %s\n", strerror(errno));
                exit(1);
        }
        session = mmap(NULL, sizeof(sessiont) * MAXSESSION, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
-       if (session <= 0)
+       if (session == MAP_FAILED)
        {
                log(0, 0, 0, 0, "Error doing mmap for sessions: %s\n", strerror(errno));
                exit(1);
        }
        radius = mmap(NULL, sizeof(radiust) * MAXRADIUS, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
-       if (radius <= 0)
+       if (radius == MAP_FAILED)
        {
                log(0, 0, 0, 0, "Error doing mmap for radius: %s\n", strerror(errno));
                exit(1);
        }
        ip_address_pool = mmap(NULL, sizeof(ippoolt) * MAXIPPOOL, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
-       if (ip_address_pool <= 0)
+       if (ip_address_pool == MAP_FAILED)
        {
                log(0, 0, 0, 0, "Error doing mmap for radius: %s\n", strerror(errno));
                exit(1);
        }
 #ifdef RINGBUFFER
        ringbuffer = mmap(NULL, sizeof(struct Tringbuffer), PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
-       if (ringbuffer <= 0)
+       if (ringbuffer == MAP_FAILED)
        {
                log(0, 0, 0, 0, "Error doing mmap for radius: %s\n", strerror(errno));
                exit(1);
@@ -1891,16 +1960,15 @@ void initdata(void)
        memset(ringbuffer, 0, sizeof(struct Tringbuffer));
 #endif
 
-#ifdef HAVE_LIBCLI
        cli_session_kill = mmap(NULL, sizeof(sessionidt) * MAXSESSION, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
-       if (cli_session_kill <= 0)
+       if (cli_session_kill == MAP_FAILED)
        {
                log(0, 0, 0, 0, "Error doing mmap for cli session kill: %s\n", strerror(errno));
                exit(1);
        }
        memset(cli_session_kill, 0, sizeof(sessionidt) * MAXSESSION);
        cli_tunnel_kill = mmap(NULL, sizeof(tunnelidt) * MAXSESSION, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
-       if (cli_tunnel_kill <= 0)
+       if (cli_tunnel_kill == MAP_FAILED)
        {
                log(0, 0, 0, 0, "Error doing mmap for cli tunnel kill: %s\n", strerror(errno));
                exit(1);
@@ -1908,33 +1976,24 @@ void initdata(void)
        memset(cli_tunnel_kill, 0, sizeof(tunnelidt) * MAXSESSION);
 
        filter_buckets = mmap(NULL, sizeof(tbft) * MAXSESSION, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
-       if (filter_buckets <= 0)
+       if (filter_buckets == MAP_FAILED)
        {
                log(0, 0, 0, 0, "Error doing mmap for filter buckets: %s\n", strerror(errno));
                exit(1);
        }
        memset(filter_buckets, 0, sizeof(tbft) * MAXSESSION);
 
-#endif
-
        memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
        memset(session, 0, sizeof(sessiont) * MAXSESSION);
        memset(radius, 0, sizeof(radiust) * MAXRADIUS);
        memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
-       for (i = 1; i < MAXTUNNEL - 1; i++)
-               tunnel[i].next = i + 1;
-       tunnel[MAXTUNNEL - 1].next = 0;
-       tunnelfree = 1;
        for (i = 1; i < MAXSESSION - 1; i++)
                session[i].next = i + 1;
        session[MAXSESSION - 1].next = 0;
        sessionfree = 1;
-       for (i = 1; i < MAXRADIUS - 1; i++)
-               radius[i].next = i + 1;
-       radius[MAXRADIUS - 1].next = 0;
-       radiusfree = 1;
        if (!*hostname)
        {
+               char *p;
                // Grab my hostname unless it's been specified
                gethostname(hostname, sizeof(hostname));
                {
@@ -1942,12 +2001,10 @@ void initdata(void)
                        if (h)
                                myip = ntohl(*(u32 *) h->h_addr);
                }
+
+               if ((p = strstr(hostname, ".optusnet.com.au"))) *p = 0;
        }
        _statistics->start_time = _statistics->last_reset = time(NULL);
-
-       // Start the timer routine off
-       time(&time_now);
-       strftime(time_now_string, 64, "%Y-%m-%d %H:%M:%S", localtime(&time_now));
 }
 
 void initiptables(void)
@@ -1957,51 +2014,80 @@ void initiptables(void)
        system("iptables -t mangle -F l2tpns");
 }
 
-ipt assign_ip_address()
+int assign_ip_address(sessionidt s)
 {
-       int c = 0;
+       unsigned i;
+       int best = -1;
+       clockt best_time = time_now;
+       char *u = session[s].user;
+       char reuse = 0;
+
 #ifdef STAT_CALLS
        STAT(call_assign_ip_address);
 #endif
-       ip_pool_index++;
-       while (1)
+       for (i = 0; i < ip_pool_size; i++)
        {
-               if (ip_pool_index >= ip_pool_size)
+               if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
+                       continue;
+
+               if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
                {
-                       if (++c == 2)
-                               return 0;
-                       ip_pool_index = 0;
+                       best = i;
+                       reuse = 1;
+                       break;
                }
-               if (!ip_address_pool[ip_pool_index].assigned && ip_address_pool[ip_pool_index].address)
+
+               if (ip_address_pool[i].last < best_time)
                {
-                       ip_address_pool[ip_pool_index].assigned = 1;
-                       log(4, ip_address_pool[ip_pool_index].address, 0, 0, "assign_ip_address(): Allocating ip address %lu from pool\n", ip_pool_index);
-                       STAT(ip_allocated);
-                       return ntohl(ip_address_pool[ip_pool_index].address);
+                       best = i;
+                       if (!(best_time = ip_address_pool[i].last))
+                               break; // never used, grab this one
                }
-               ip_pool_index++;
        }
-       return 0;
+
+       if (best < 0)
+       {
+               log(0, 0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
+               return 0;
+       }
+
+       session[s].ip = ntohl(ip_address_pool[best].address);
+       session[s].ip_pool_index = best;
+       ip_address_pool[best].assigned = 1;
+       ip_address_pool[best].last = time_now;
+       ip_address_pool[best].session = s;
+       if (session[s].walled_garden)
+               /* Don't track addresses of users in walled garden (note: this
+                  means that their address isn't "sticky" even if they get
+                  un-gardened). */
+               ip_address_pool[best].user[0] = 0;
+       else
+               strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
+
+       STAT(ip_allocated);
+       log(4, ip_address_pool[best].address, s, session[s].tunnel,
+               "assign_ip_address(): %s ip address %d from pool\n", reuse ? "Reusing" : "Allocating", best);
+
+       return 1;
 }
 
-void free_ip_address(ipt address)
+void free_ip_address(sessionidt s)
 {
-       int i;
-       ipt a;
+       int i = session[s].ip_pool_index;
+
 #ifdef STAT_CALLS
        STAT(call_free_ip_address);
 #endif
 
-       a = ntohl(address);
-       for (i = 0; i <= ip_pool_size; i++)
-       {
-               if (ip_address_pool[i].address == a)
-               {
-                       STAT(ip_freed);
-                       ip_address_pool[i].assigned = 0;
-               }
-       }
-       uncache_sessionid(htonl(address));
+       if (!session[s].ip)
+               return; // what the?
+
+       STAT(ip_freed);
+       uncache_sessionid(session[s].ip);
+       session[s].ip = 0;
+       ip_address_pool[i].assigned = 0;
+       ip_address_pool[i].session = 0;
+       ip_address_pool[i].last = time_now;
 }
 
 // Initialize the IP address pool
@@ -2037,7 +2123,7 @@ void initippool()
                                exit(-1);
                        }
                        // This entry is for a specific IP only
-                       if (src != bind_address)
+                       if (src != config->bind_address)
                                continue;
                        *p = ':';
                        pool = p+1;
@@ -2053,7 +2139,7 @@ void initippool()
                        *p++ = 0;
                        if (!*p || !(numbits = atoi(p)))
                        {
-                               log(0, 0, 0, 0, "Invalid pool range %s/\n", buf, p);
+                               log(0, 0, 0, 0, "Invalid pool range %s\n", buf);
                                continue;
                        }
                        start = end = ntohl(inet_addr(pool));
@@ -2068,9 +2154,9 @@ void initippool()
                        }
 
                        // Add a static route for this pool
-                       log(5, 0, 0, 0, "Adding route for address pool %s/%d\n", inet_toa(htonl(start)), 32+mask);
+                       log(5, 0, 0, 0, "Adding route for address pool %s/%lu\n", inet_toa(htonl(start)), 32 + mask);
                        memset(&r, 0, sizeof(r));
-                       r.rt_dev = tapdevice;
+                       r.rt_dev = config->tapdevice;
                        r.rt_dst.sa_family = AF_INET;
                        *(u32 *) & (((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr) = htonl(start);
                        r.rt_genmask.sa_family = AF_INET;
@@ -2078,7 +2164,8 @@ void initippool()
                        r.rt_flags = (RTF_UP | RTF_STATIC);
                        if (ioctl(ifrfd, SIOCADDRT, (void *) &r) < 0)
                        {
-                               log(0, 0, 0, 0, "Error adding ip address pool route %s/%d: %s\n", inet_toa(start), mask, strerror(errno));
+                               log(0, 0, 0, 0, "Error adding ip address pool route %s/%lu: %s\n",
+                                       inet_toa(start), mask, strerror(errno));
                        }
                }
                else
@@ -2099,6 +2186,7 @@ void snoop_send_packet(char *packet, u16 size)
        if (!snoop_addr.sin_port || snoopfd <= 0 || size <= 0 || !packet)
                return;
 
+       log(5, 0, 0, 0, "Snooping packet at %p (%d bytes) to %s:%d\n", packet, size, inet_toa(snoop_addr.sin_addr.s_addr), htons(snoop_addr.sin_port));
        if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
                log(0, 0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
        STAT(packets_snooped);
@@ -2116,11 +2204,11 @@ void dump_acct_info()
        STAT(call_dump_acct_info);
 #endif
     strftime(timestr, 64, "%Y%m%d%H%M%S", localtime(&t));
-    snprintf(filename, 1024, "%s/%s", accounting_dir, timestr);
+    snprintf(filename, 1024, "%s/%s", config->accounting_dir, timestr);
 
     for (i = 0; i < MAXSESSION; i++)
     {
-       if (!session[i].opened || !session[i].cin || !session[i].cout || !*session[i].user || session[i].walled_garden)
+       if (!session[i].opened || !session[i].ip || !session[i].cin || !session[i].cout || !*session[i].user || session[i].walled_garden)
                continue;
        if (!f)
        {
@@ -2163,137 +2251,119 @@ int main(int argc, char *argv[])
 
        _program_name = strdup(argv[0]);
 
-       {
-               struct rlimit rlim;
-               rlim.rlim_cur = RLIM_INFINITY;
-               rlim.rlim_max = RLIM_INFINITY;
-               // Remove the maximum core size
-               setrlimit(RLIMIT_CORE, &rlim);
-               // Make core dumps go to /tmp
-               chdir("/tmp");
-       }
-
        time(&basetime);             // start clock
        // scan args
 
-       while ((o = getopt(argc, argv, "vc:f:h:a:")) >= 0)
+       while ((o = getopt(argc, argv, "vc:h:a:")) >= 0)
        {
                switch (o)
                {
                        case 'v':
-                               debug++;
-                               break;
-                       case 'c':
-                               config_file = strdup(optarg);
-                               break;
-                       case 'f':
-                               log_filename = strdup(optarg);
+                               config->debug++;
                                break;
                        case 'h':
-                               strncpy(hostname, optarg, 1000);
-                               break;
-                       case 'a':
-                               myip = inet_addr(optarg);
-                               if (myip == INADDR_NONE) {
-                                       log(0, 0, 0, 0, "Invalid ip %s\n", optarg);
-                                       exit(-1);
-                               }
-                               bind_address = myip;
-                               handle_interface = 1;
+                               strncpy(hostname, optarg, 999);
                                break;
                        case '?':
                        default:
-                               printf("Args are:\n\t-c <file>\tConfig file\n\t-h <hostname>\tForce hostname\n\t-a <address>\tUse specific address\n\t-f <file>\tLog File\n\t-v\t\tDebug\n");
+                               printf("Args are:\n\t-c <file>\tConfig file\n\t-h <hostname>\tForce hostname\n\t-a <address>\tUse specific address\n\t-v\t\tDebug\n");
                                return (0);
                                break;
                }
        }
 
+       // Start the timer routine off
+       time(&time_now);
+       strftime(time_now_string, 64, "%Y-%m-%d %H:%M:%S", localtime(&time_now));
+       signal(SIGALRM, sigalrm_handler);
+       siginterrupt(SIGALRM, 0);
+
        initiptables();
        initplugins();
-       read_config_file();
        initdata();
-       log(0, 0, 0, 0, "$Id: l2tpns.c,v 1.1 2003/12/16 07:07:39 fred_nerk Exp $\n(c) Copyright 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
+       init_cli();
+       read_config_file();
+       log(0, 0, 0, 0, "$Id: l2tpns.c,v 1.6 2004/05/24 04:20:28 fred_nerk Exp $\n(c) Copyright 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
+       {
+               struct rlimit rlim;
+               rlim.rlim_cur = RLIM_INFINITY;
+               rlim.rlim_max = RLIM_INFINITY;
+               // Remove the maximum core size
+               if (setrlimit(RLIMIT_CORE, &rlim) < 0)
+                       log(0, 0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
+               // Make core dumps go to /tmp
+               chdir("/tmp");
+       }
 
        /* Start up the cluster first, so that we don't have two machines with
         * the same IP at once.
         * This is still racy, but the second GARP should fix that
         */
-       cluster_init(bind_address, 0);
-       cluster_send_message(cluster_address, bind_address, C_HELLO, hostname, strlen(hostname));
+       cluster_init(config->bind_address, 0);
+       cluster_send_message(config->cluster_address, config->bind_address, C_HELLO, hostname, strlen(hostname));
 
        inittap();
-       log(1, 0, 0, 0, "Set up on interface %s\n", tapdevice);
+       log(1, 0, 0, 0, "Set up on interface %s\n", config->tapdevice);
 
        initudp();
        initrad();
        initippool();
        init_rl();
-       if (handle_interface) {
-               send_garp(bind_address);
-       }
-       read_state();
+       if (config->bind_address)
+               send_garp(config->bind_address);
 
-#ifdef HAVE_LIBCLI
-       init_cli();
-#endif
+       // If NOSTATEFILE exists, we will ignore any updates from the cluster master for this execution
+       if (!unlink(NOSTATEFILE))
+           config->ignore_cluster_updates = 1;
+
+       read_state();
 
-       signal(SIGALRM, sigalrm_handler);
        signal(SIGHUP, sighup_handler);
        signal(SIGTERM, sigterm_handler);
        signal(SIGINT, sigterm_handler);
        signal(SIGQUIT, sigquit_handler);
        signal(SIGCHLD, sigchild_handler);
-       signal(SIGSEGV, sigsegv_handler);
-       if (debug)
-       {
-               int n;
-               for (n = 0; n < numradiusservers; n++)
-                       log(1, 0, 0, 0, "RADIUS to %s\n", inet_toa(htonl(radiusserver[n])));
-       }
 
        alarm(1);
 
        // Drop privileges here
-       if (target_uid > 0 && geteuid() == 0)
-               setuid(target_uid);
+       if (config->target_uid > 0 && geteuid() == 0)
+               setuid(config->target_uid);
 
        mainloop();
-
-       if (l2tpsecret) free(l2tpsecret);
-       if (log_filename) free(log_filename);
-       if (snoop_destination_host) free(snoop_destination_host);
-       if (radiussecret) free(radiussecret);
-
        return 0;
 }
 
 void sighup_handler(int junk)
 {
-       if (log_stream != stderr)
+       if (log_stream && log_stream != stderr)
+       {
                fclose(log_stream);
+               log_stream = NULL;
+       }
 
-       log_stream = NULL;
        read_config_file();
 }
 
 void sigalrm_handler(int junk)
 {
        // Log current traffic stats
-       if (dump_speed)
-       {
-               printf("UDP-ETH:%1.0f/%1.0f  ETH-UDP:%1.0f/%1.0f  TOTAL:%0.1f   IN:%lu OUT:%lu\n",
-                       (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;
-       }
+       snprintf(config->bandwidth, sizeof(config->bandwidth),
+               "UDP-ETH:%1.0f/%1.0f  ETH-UDP:%1.0f/%1.0f  TOTAL:%0.1f   IN:%lu OUT:%lu",
+               (udp_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);
@@ -2311,187 +2381,207 @@ void sigalrm_handler(int junk)
 void sigterm_handler(int junk)
 {
        log(1, 0, 0, 0, "Shutting down cleanly\n");
-       if (config_save_state)
+       if (config->save_state)
                dump_state();
        main_quit++;
 }
 
 void sigquit_handler(int junk)
 {
+       FILE *f;
        int i;
+
        log(1, 0, 0, 0, "Shutting down without saving sessions\n");
-       for (i = 0; i < MAXSESSION; i++)
+       for (i = 1; i < MAXSESSION; i++)
        {
                if (session[i].opened)
                        sessionkill(i, "L2TPNS Closing");
        }
-       for (i = 0; i < MAXTUNNEL; i++)
+       for (i = 1; i < MAXTUNNEL; i++)
        {
-               if (tunnel[i].ip)
+               if (tunnel[i].ip || tunnel[i].state)
                        tunnelshutdown(i, "L2TPNS Closing");
        }
-       main_quit++;
-}
 
-void sigchild_handler(int signal)
-{
-       int status;
-       int pid;
+       cluster_send_goodbye();
 
-       pid = wait(&status);
-#ifdef HAVE_LIBCLI
-       status = (WIFEXITED(status)) ? WEXITSTATUS(status) : 0;
-       if (pid == cli_pid)
-       {
-               if (status == 0)
-                       log(3, 0, 0, 0, "CLI client closed connection\n");
-               else
-                       log(2, 0, 0, 0, "CLI child died with rc %d!\n", status);
-       }
-#endif
-}
+       // Touch a file which says not to reload the state
+       f = fopen(NOSTATEFILE, "w");
+       if (f) fclose(f);
 
-void *backtrace_buffer[30] = {0};
+       main_quit++;
+}
 
-void sigsegv_handler(int signal)
+void sigchild_handler(int signal)
 {
-       log(0, 0, 0, 0, "----------------------------------------------\n");
-       log(0, 0, 0, 0, "- SEGFAULT!                                  -\n");
-       log(0, 0, 0, 0, "----------------------------------------------\n");
-       _exit(0);
+       while (waitpid(-1, NULL, WNOHANG) > 0)
+           ;
 }
 
 void read_state()
 {
-       struct stat sb;
-       FILE *f;
+    struct stat sb;
+    int i;
+    ippoolt itmp;
+    FILE *f;
+    char magic[sizeof(DUMP_MAGIC)-1];
+    u32 buf[2];
 
-       if (!config_save_state) return;
+    if (!config->save_state)
+       return;
 
-       if (stat(STATEFILE, &sb) < 0)
-               return;
+    // Ignore saved state if NOSTATEFILE exists
+    if (config->ignore_cluster_updates)
+    {
+       unlink(STATEFILE);
+       return;
+    }
 
-       if (sb.st_mtime < (time(NULL) - 60))
-       {
-               log(0, 0, 0, 0, "State file is too old to read\n");
-               unlink(STATEFILE);
-               return;
-       }
+    if (stat(STATEFILE, &sb) < 0)
+       return;
+
+    if (sb.st_mtime < (time(NULL) - 60))
+    {
+       log(0, 0, 0, 0, "State file is too old to read, ignoring\n");
+       unlink(STATEFILE);
+       return;
+    }
 
-       if (!(f = fopen(STATEFILE, "r")))
+    f = fopen(STATEFILE, "r");
+    unlink(STATEFILE);
+
+    if (!f)
+    {
+       log(0, 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, 0, "Bad state file magic\n");
+       exit(1);
+    }
+
+    log(1, 0, 0, 0, "Reading state information\n");
+    if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] > MAXIPPOOL || buf[1] != sizeof(ippoolt))
+    {
+       log(0, 0, 0, 0, "Error/mismatch reading ip pool header from state file\n");
+       exit(1);
+    }
+
+    if (buf[0] > ip_pool_size)
+    {
+       log(0, 0, 0, 0, "ip pool has shrunk!  state = %d, current = %d\n", buf[0], ip_pool_size);
+       exit(1);
+    }
+
+    log(2, 0, 0, 0, "Loading %u ip addresses\n", buf[0]);
+    for (i = 0; i < buf[0]; i++)
+    {
+       if (fread(&itmp, sizeof(itmp), 1, f) != 1)
        {
-               log(0, 0, 0, 0, "Can't read state file: %s\n", strerror(errno));
-               unlink(STATEFILE);
-               return;
+           log(0, 0, 0, 0, "Error reading ip %d from state file: %s\n", i, strerror(errno));
+           exit(1);
        }
-       fseek(f, 0, 0);
 
-       log(1, 0, 0, 0, "Reading state information\n");
+       if (itmp.address != ip_address_pool[i].address)
        {
-               u32 i, numtunnels;
-               if (fread(&numtunnels, sizeof(numtunnels), 1, f) <= 0)
-               {
-                       log(0, 0, 0, 0, "Error reading saved state (tunnel count): %s\n", strerror(errno));
-                       fclose(f);
-                       unlink(STATEFILE);
-                       return;
-               }
-               log(2, 0, 0, 0, "Reading %lu tunnels\n", numtunnels);
-               fread(tunnel, sizeof(tunnelt), numtunnels, f);
-               tunnelfree = 0;
-               for (i = 0; i < numtunnels; i++)
-               {
-                       tunnel[i].controlc = 0;
-                       tunnel[i].controls = NULL;
-                       tunnel[i].controle = NULL;
-                       if (*tunnel[i].hostname)
-                       {
-                               log(3, 0, 0, 0, "Created tunnel for %s\n", tunnel[i].hostname);
-                               tunnelfree = i;
-                       }
-               }
-               tunnelfree++;
+           log(0, 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, 0, "Error/mismatch reading tunnel header from state file\n");
+       exit(1);
+    }
+
+    log(2, 0, 0, 0, "Loading %u tunnels\n", MAXTUNNEL);
+    if (fread(tunnel, sizeof(tunnelt), MAXTUNNEL, f) != MAXTUNNEL)
+    {
+       log(0, 0, 0, 0, "Error reading tunnel data from state file\n");
+       exit(1);
+    }
+
+    for (i = 0; i < MAXTUNNEL; i++)
+    {
+       tunnel[i].controlc = 0;
+       tunnel[i].controls = NULL;
+       tunnel[i].controle = NULL;
+       if (*tunnel[i].hostname)
+           log(3, 0, 0, 0, "Created tunnel for %s\n", tunnel[i].hostname);
+    }
+
+    if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] != MAXSESSION || buf[1] != sizeof(sessiont))
+    {
+       log(0, 0, 0, 0, "Error/mismatch reading session header from state file\n");
+       exit(1);
+    }
+
+    log(2, 0, 0, 0, "Loading %u sessions\n", MAXSESSION);
+    if (fread(session, sizeof(sessiont), MAXSESSION, f) != MAXSESSION)
+    {
+       log(0, 0, 0, 0, "Error reading session data from state file\n");
+       exit(1);
+    }
+
+    for (i = 0; i < MAXSESSION; i++)
+    {
+       session[i].tbf = 0;
+       if (session[i].opened)
        {
-               u32 i, numsessions;
-               if (fread(&numsessions, sizeof(numsessions), 1, f) <= 0)
-               {
-                       log(0, 0, 0, 0, "Error reading saved state (session count): %s\n", strerror(errno));
-                       fclose(f);
-                       unlink(STATEFILE);
-                       return;
-               }
-               log(2, 0, 0, 0, "Reading %lu sessions\n", numsessions);
-               if (fread(session, sizeof(sessiont), numsessions, f) < numsessions)
-               {
-                       log(0, 0, 0, 0, "Error reading saved state (%d sessions): %s\n", numsessions, strerror(errno));
-                       fclose(f);
-                       unlink(STATEFILE);
-                       return;
-               }
-               for (i = 0; i < numsessions; i++)
-               {
-                       session[i].tbf = 0;
-                       session[i].throttle = 0;
-                       if (session[i].opened)
-                       {
-                               log(2, 0, i, 0, "Loaded active session for user %s\n", session[i].user);
-                               if (session[i].ip && session[i].ip != 0xFFFFFFFE)
-                               {
-                                       int x;
-                                       sessionsetup(session[i].tunnel, i, 0);
-                                       for (x = 0; x < MAXIPPOOL && ip_address_pool[x].address; x++)
-                                       {
-                                               if (ip_address_pool[x].address == session[i].ip)
-                                               {
-                                                       ip_address_pool[x].assigned = 1;
-                                                       break;
-                                               }
-                                       }
-                               }
-                               else
-                               {
-                                       log(2, 0, i, 0, "No IP for session\n");
-                               }
-                       }
-               }
-               for (i = 0; i < numsessions && session[i].opened; i++)
-                       sessionfree = session[i].next;
+           log(2, 0, i, 0, "Loaded active session for user %s\n", session[i].user);
+           if (session[i].ip && session[i].ip != 0xFFFFFFFE)
+               sessionsetup(session[i].tunnel, i, 0);
        }
-       fclose(f);
-       log(0, 0, 0, 0, "Loaded saved state information\n");
-       unlink(STATEFILE);
+    }
+
+    fclose(f);
+    log(0, 0, 0, 0, "Loaded saved state information\n");
 }
 
 void dump_state()
 {
-       FILE *f;
+    FILE *f;
+    u32 buf[2];
 
-       if (!config_save_state) return;
+    if (!config->save_state)
+       return;
 
-       if ((f = fopen(STATEFILE, "w")))
-       {
-               u32 i;
-               log(1, 0, 0, 0, "Dumping state information\n");
+    do {
+       if (!(f = fopen(STATEFILE, "w")))
+           break;
 
-               i = MAXTUNNEL;
-               fwrite(&i, sizeof(i), 1, f);    // Number of tunnels
+       log(1, 0, 0, 0, "Dumping state information\n");
 
-               log(2, 0, 0, 0, "Dumping %lu tunnels\n", i);
-               fwrite(tunnel, sizeof(tunnelt), MAXTUNNEL, f);
+       if (fwrite(DUMP_MAGIC, sizeof(DUMP_MAGIC)-1, 1, f) != 1) break;
 
-               i = MAXSESSION;
-               fwrite(&i, sizeof(i), 1, f);    // Number of sessions
-               log(2, 0, 0, 0, "Dumping %lu sessions\n", i);
-               fwrite(session, sizeof(sessiont), MAXSESSION, f);
+       log(2, 0, 0, 0, "Dumping %u ip addresses\n", ip_pool_size);
+       buf[0] = ip_pool_size;
+       buf[1] = sizeof(ippoolt);
+       if (fwrite(buf, sizeof(buf), 1, f) != 1) break;
+       if (fwrite(ip_address_pool, sizeof(ippoolt), ip_pool_size, f) != ip_pool_size) break;
 
-               fclose(f);
-       }
-       else
-       {
-               log(0, 0, 0, 0, "Can't write state information: %s\n", strerror(errno));
-       }
-       return;
+       log(2, 0, 0, 0, "Dumping %u tunnels\n", MAXTUNNEL);
+       buf[0] = MAXTUNNEL;
+       buf[1] = sizeof(tunnelt);
+       if (fwrite(buf, sizeof(buf), 1, f) != 1) break;
+       if (fwrite(tunnel, sizeof(tunnelt), MAXTUNNEL, f) != MAXTUNNEL) break;
+
+       log(2, 0, 0, 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, 0, "Can't write state information: %s\n", strerror(errno));
+    unlink(STATEFILE);
 }
 
 void build_chap_response(char *challenge, u8 id, u16 challenge_length, char **challenge_response)
@@ -2499,222 +2589,133 @@ void build_chap_response(char *challenge, u8 id, u16 challenge_length, char **ch
        MD5_CTX ctx;
        *challenge_response = NULL;
 
-       if (!l2tpsecret || !*l2tpsecret)
+       if (!*config->l2tpsecret)
        {
                log(0, 0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
                return;
        }
 
-       /*
-       if (challenge_length != 16)
-       {
-               log(0, 0, 0, 0, "Challenge length != 16.\n");
-               return;
-       }
-       */
-
        log(4, 0, 0, 0, "   Building challenge response for CHAP request\n");
 
        *challenge_response = (char *)calloc(17, 1);
 
        MD5Init(&ctx);
        MD5Update(&ctx, &id, 1);
-       MD5Update(&ctx, l2tpsecret, strlen(l2tpsecret));
+       MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
        MD5Update(&ctx, challenge, challenge_length);
        MD5Final(*challenge_response, &ctx);
 
        return;
 }
 
-void read_config_file()
+static int facility_value(char *name)
 {
-       FILE *f;
-       char *buf;
+    int i;
+    for (i = 0; facilitynames[i].c_name; i++)
+    {
+       if (strcmp(facilitynames[i].c_name, name) == 0)
+           return facilitynames[i].c_val;
+    }
+    return 0;
+}
 
-       if (!config_file) return;
-       if (!(f = fopen(config_file, "r"))) {
-               fprintf(stderr, "Can't open config file %s: %s\n", config_file, strerror(errno));
-               return;
-       }
+void update_config()
+{
+       int i;
 
-       if (radiussecret)
-       {
-               free(radiussecret);
-               radiussecret = NULL;
-       }
+       snoop_addr.sin_family = AF_INET;
+       snoop_addr.sin_addr.s_addr = config->snoop_destination_host;
+       snoop_addr.sin_port = htons(config->snoop_destination_port);
 
-       if (l2tpsecret)
+       // Update logging
+       closelog();
+       syslog_log = 0;
+       if (log_stream)
        {
-               free(l2tpsecret);
-               l2tpsecret = NULL;
-       }
-
-       if (log_filename)
-       {
-               free(log_filename);
-               log_filename = NULL;
+               fclose(log_stream);
+               log_stream = NULL;
        }
-
-       if (snoop_destination_host)
+       if (*config->log_filename)
        {
-               free(snoop_destination_host);
-               snoop_destination_host = NULL;
-       }
-
-       if (numradiusservers) {
-               int n;
-               for (n = 0; n < numradiusservers; n++)
-                       radiusserver[n] = 0;
-               numradiusservers = 0;
-       }
-
-       snoop_destination_port = 0L;
-       config_save_state = 0;
-       rl_rate = 0L;
-       debug = 1;
-       default_dns1 = default_dns2 = 0;
-       radius_accounting = 0;
-
-       buf = (char *)malloc(4096);
-
-       while (fgets(buf, 4096, f)) {
-               char *p, *t;
-
-               if (*buf == '#') continue;
-               if ((p = strchr(buf, '\n'))) *p = 0;
-               p = t = strchr(buf, '=');
-               if (!p) continue;
-               *p = 0; p++;
-               t--;
-               while (*p && *p == ' ') p++;
-               while (*t && *t == ' ') *t-- = 0;
-
-               if (strcmp(buf, "log file") == 0) {
-                       if (!log_filename)
-                               log_filename = strdup(p);
-               } else if (strcmp(buf, "l2tp secret") == 0) {
-                       if (!l2tpsecret)
-                               l2tpsecret = strdup(p);
-                       log(0, 0, 0, 0, "L2TP Secret is \"%s\"\n", l2tpsecret);
-               } else if (strcmp(buf, "radius secret") == 0) {
-                       if (!radiussecret)
-                               radiussecret = strdup(p);
-                       log(4, 0, 0, 0, "Radius Secret is \"%s\"\n", radiussecret);
-               } else if (strcmp(buf, "radius accounting") == 0) {
-                       radius_accounting = atoi(p);
-                       log(4, 0, 0, 0, "Radius Account is %s\n", radius_accounting ? "on" : "off");
-               } else if (strcmp(buf, "throttle rate") == 0) {
-                       rl_rate = atol(p);
-                       if (rl_rate == 0)
-                       {
-                               log(1, 0, 0, 0, "Disabled throttling.\n");
-                       }
-                       else
+               if (strstr(config->log_filename, "syslog:") == config->log_filename)
+               {
+                       char *p = config->log_filename + 7;
+                       if (*p)
                        {
-                               log(1, 0, 0, 0, "Enabled throttling (rate is %lu kbits/s)\n", rl_rate);
-                       }
-               } else if (strcmp(buf, "debug") == 0) {
-                       debug = atoi(p);
-                       log(debug, 0, 0, 0, "Set debugging level to %d\n", debug);
-               } else if (strcmp(buf, "accounting dir") == 0) {
-                       accounting_dir = strdup(p);
-                       log(debug, 0, 0, 0, "Will dump accounting information to %s\n", accounting_dir);
-               } else if (strcmp(buf, "dns server") == 0) {
-                       unsigned long addr = 0;
-                       if (inet_aton(p, (struct in_addr *)&addr) < 0) {
-                               printf("Invalid DNS server %s\n", p);
-                               continue;
+                               openlog("l2tpns", LOG_PID, facility_value(p));
+                               syslog_log = 1;
                        }
-                       if (default_dns1 == 0)
-                               default_dns1 = addr;
-                       else if (default_dns2 == 0)
-                               default_dns2 = addr;
-               } else if (strcmp(buf, "radius server") == 0) {
-                       struct hostent *h = gethostbyname(p);
-                       if (h)
+               }
+               else if (strchr(config->log_filename, '/') == config->log_filename)
+               {
+                       if ((log_stream = fopen((char *)(config->log_filename), "a")))
                        {
-                               while (*h->h_addr_list)
-                               {
-                                       ipt ip = ntohl(*(u32 *) * h->h_addr_list);
-                                       if (numradiusservers < MAXRADSERVER)
-                                               radiusserver[numradiusservers++] = ip;
-                                       else
-                                               log(0, 0, 0, 0, "Too many RADIUS IPs\n");
-                                       h->h_addr_list++;
-                               }
+                               fseek(log_stream, 0, SEEK_END);
+                               setbuf(log_stream, NULL);
                        }
                        else
-                       {        // may be IP?
-                               ipt ip = ntohl(inet_addr(p));
-                               if (ip && ip != 0xFFFFFFFF)
-                               {
-                                       if (numradiusservers < MAXRADSERVER)
-                                               radiusserver[numradiusservers++] = ip;
-                                       else
-                                               log(0, 0, 0, 0, "Too many RADIUS IPs\n");
-                               }
-                               else
-                                       log(0, 0, 0, 0, "Unknown server %s\n", p);
-                       }
-               } else if (strcmp(buf, "snoop host") == 0) {
-                       snoop_destination_host = strdup(p);
-               } else if (strcmp(buf, "snoop port") == 0) {
-                       snoop_destination_port = atol(p);
-               } else if (strcmp(buf, "bind address") == 0) {
-                       if (!bind_address)
                        {
-                               // Already overridden on the command line
-                               bind_address = inet_addr(p);
-                               handle_interface = 1;
-                       }
-               } else if (strcmp(buf, "dump speed") == 0) {
-                       dump_speed = atoi(p);
-               } else if (strcmp(buf, "setuid") == 0) {
-                       target_uid = atoi(p);
-               } else if (strcmp(buf, "cluster master") == 0) {
-                       struct hostent *h = gethostbyname(p);
-                       if (h)
-                       {
-                               if (*h->h_addr_list)
-                               {
-                                       cluster_address = *(u32 *) *h->h_addr_list;
-                               }
+                               log_stream = stderr;
+                               setbuf(log_stream, NULL);
                        }
-                       else
-                       {        // may be IP?
-                               cluster_address = inet_addr(p);
-                       }
-               } else if (strcmp(buf, "save state") == 0) {
-                       if (strcasecmp(p, "no") == 0) {
-                               config_save_state = 0;
-                       } else {
-                               config_save_state = 1;
-                       }
-               } else if (strcmp(buf, "plugin") == 0) {
-                       add_plugin(p);
-               } else {
-                       struct param_config cp = { buf, p };
-                       int rc = run_plugins(PLUGIN_CONFIG, &cp);
-                       if (rc == 0) log(0, 0, 0, 0, "Unknown config directive \"%s\"\n", buf);
                }
        }
+       else
+       {
+               log_stream = stderr;
+               setbuf(log_stream, NULL);
+       }
+
+
+       // Update radius
+       config->numradiusservers = 0;
+       for (i = 0; i < MAXRADSERVER; i++)
+               if (config->radiusserver[i]) config->numradiusservers++;
 
-       if (snoop_destination_host)
+       if (!config->numradiusservers)
        {
-               if (inet_aton(snoop_destination_host, &snoop_addr.sin_addr))
+               log(0, 0, 0, 0, "No RADIUS servers defined!\n");
+       }
+
+       config->num_radfds = 2 << RADIUS_SHIFT;
+
+       // Update plugins
+       for (i = 0; i < MAXPLUGINS; i++)
+       {
+               if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
+                       continue;
+               if (*config->plugins[i])
                {
-                       snoop_addr.sin_port = htons(snoop_destination_port);
-                       snoop_addr.sin_family = AF_INET;
+                       // Plugin added
+                       add_plugin(config->plugins[i]);
                }
-               else
+               else if (*config->old_plugins[i])
                {
-                       log(0, 0, 0, 0, "Can't find address for snoop host %s\n", snoop_destination_host);
+                       // Plugin removed
+                       remove_plugin(config->old_plugins[i]);
                }
        }
+       memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
+       if (!config->cleanup_interval) config->cleanup_interval = 10;
+       if (!config->multi_read_count) config->multi_read_count = 1;
+       config->reload_config = 0;
+}
 
-       free(buf);
+void read_config_file()
+{
+       FILE *f;
+
+       if (!config->config_file) return;
+       if (!(f = fopen(config->config_file, "r"))) {
+               fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
+               return;
+       }
+
+       log(3, 0, 0, 0, "Reading config file %s\n", config->config_file);
+       cli_do_file(f);
+       log(3, 0, 0, 0, "Done reading config file\n");
        fclose(f);
-       log(2, 0, 0, 0, "Done reading config file\n");
+       update_config();
 }
 
 int sessionsetup(tunnelidt t, sessionidt s, u8 routes)
@@ -2731,22 +2732,15 @@ int sessionsetup(tunnelidt t, sessionidt s, u8 routes)
                log(0, session[s].ip, s, t, "VERY VERY BAD! sessionsetup() called with no session[s].ip\n");
                return 1;
        }
-       if (session[s].ip == 0xFFFFFFFE)
-       {
-               session[s].ip = assign_ip_address(); // Assign one from the pool;
-
-               log(2, session[s].ip, s, t, "IP assigned is a magic token. Assign address from pool: %s\n",
-                               inet_toa(htonl(session[s].ip)));
-       }
 
        // Make sure this is right
        session[s].tunnel = t;
        // zap old sessions with same IP and/or username
-       // Don't kill walled_garden sessions - doing so leads to a DoS
+       // Don't kill gardened sessions - doing so leads to a DoS
        // from someone who doesn't need to know the password
        ip = session[s].ip;
        user = session[s].user;
-       for (i = 0; i < MAXSESSION; i++)
+       for (i = 1; i < MAXSESSION; i++)
        {
                if (i == s) continue;
                if (ip == session[i].ip) sessionkill(i, "Duplicate IP address");
@@ -2772,14 +2766,16 @@ int sessionsetup(tunnelidt t, sessionidt s, u8 routes)
        // Force throttling on or off
        // This has the advantage of cleaning up after another throttled user who may have left
        // firewall rules lying around
-       throttle_session(s, session[s].throttle);
+       session[s].throttle = throttle_session(s, session[s].throttle);
 
        {
                struct param_new_session data = { &tunnel[t], &session[s] };
                run_plugins(PLUGIN_NEW_SESSION, &data);
        }
 
-       session[s].sid = ++last_sid;
+       if (!session[s].sid)
+               session[s].sid = ++last_sid;
+
        cache_sessionid(htonl(session[s].ip), s);
 
        cluster_send_session(s);
@@ -2860,7 +2856,7 @@ void add_plugin(char *plugin_name)
                int *v = dlsym(p, "__plugin_api_version");
                if (!v || *v != PLUGIN_API_VERSION)
                {
-                       log(1, 0, 0, 0, "   Plugin load failed: API version mismatch\n", dlerror());
+                       log(1, 0, 0, 0, "   Plugin load failed: API version mismatch: %s\n", dlerror());
                        dlclose(p);
                        return;
                }
@@ -2869,14 +2865,14 @@ void add_plugin(char *plugin_name)
        initfunc = dlsym(p, "plugin_init");
        if (!initfunc)
        {
-               log(1, 0, 0, 0, "   Plugin load failed: function plugin_init() does not exist.\n", dlerror());
+               log(1, 0, 0, 0, "   Plugin load failed: function plugin_init() does not exist: %s\n", dlerror());
                dlclose(p);
                return;
        }
 
        if (!initfunc(&funcs))
        {
-               log(1, 0, 0, 0, "   Plugin load failed: plugin_init() returned FALSE.\n", dlerror());
+               log(1, 0, 0, 0, "   Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
                dlclose(p);
                return;
        }
@@ -2951,7 +2947,8 @@ void processcontrol(u8 * buf, int len, struct sockaddr_in *addr)
        struct param_control param = { buf, len, ntohl(addr->sin_addr.s_addr), ntohs(addr->sin_port), NULL, 0, 0 };
 
        log(4, ntohl(addr->sin_addr.s_addr), 0, 0, "Received ");
-       dump_packet(buf, log_stream);
+       if (log_stream)
+               dump_packet(buf, log_stream);
 
        resp = calloc(1400, 1);
        l = new_packet(PKT_RESP_ERROR, resp);
@@ -2964,18 +2961,7 @@ void processcontrol(u8 * buf, int len, struct sockaddr_in *addr)
        param.response = resp;
        param.response_length = l;
 
-       if (param.type == PKT_LOAD_PLUGIN && param.data_length)
-       {
-               add_plugin(param.data);
-       }
-       else if (param.type == PKT_UNLOAD_PLUGIN && param.data_length)
-       {
-               remove_plugin(param.data);
-       }
-       else
-       {
-               run_plugins(PLUGIN_CONTROL, &param);
-       }
+       run_plugins(PLUGIN_CONTROL, &param);
 
        if (param.send_response)
        {
@@ -2986,3 +2972,46 @@ void processcontrol(u8 * buf, int len, struct sockaddr_in *addr)
        free(resp);
 }
 
+/*
+ * HACK
+ * Go through all of the tunnels and do some cleanups
+ */
+void tunnel_clean()
+{
+       int i;
+
+       log(1, 0, 0, 0, "Cleaning tunnels array\n");
+
+       for (i = 1; i < MAXTUNNEL; i++)
+       {
+               if (!tunnel[i].ip
+                               || !*tunnel[i].hostname
+                               || (tunnel[i].state == TUNNELDIE && tunnel[i].die >= time_now))
+               {
+                       tunnelclear(i);
+               }
+       }
+}
+
+void tunnelclear(tunnelidt t)
+{
+       if (!t) return;
+       memset(&tunnel[t], 0, sizeof(tunnel[t]));
+       tunnel[t].state = TUNNELFREE;
+}
+
+tunnelidt new_tunnel()
+{
+       tunnelidt i;
+       for (i = 1; i < MAXTUNNEL; i++)
+       {
+               if (tunnel[i].state == TUNNELFREE)
+               {
+                       log(4, 0, 0, i, "Assigning tunnel ID %d\n", i);
+                       return i;
+               }
+       }
+       log(0, 0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
+       return 0;
+}
+