+// L2TP Network Server
+// Adrian Kennard 2002
+// Copyright (c) 2003, 2004, 2005 Optus Internet Engineering
+// Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced
+// vim: sw=8 ts=8
+
+char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.161.2.1 2006/06/22 15:30:50 bodea Exp $";
+
+#include <arpa/inet.h>
+#include <assert.h>
+#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>
+#include <sys/mman.h>
+#include <netdb.h>
+#include <netinet/in.h>
+#include <netinet/ip6.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <ctype.h>
+#include <sys/ioctl.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/time.h>
+#include <sys/resource.h>
+#include <sys/wait.h>
+#include <linux/if.h>
+#include <stddef.h>
+#include <time.h>
+#include <dlfcn.h>
+#include <unistd.h>
+#include <sched.h>
+#include <sys/sysinfo.h>
+#include <libcli.h>
+
+#include "md5.h"
+#include "l2tpns.h"
+#include "cluster.h"
+#include "plugin.h"
+#include "ll.h"
+#include "constants.h"
+#include "control.h"
+#include "util.h"
+#include "tbf.h"
+
+#ifdef BGP
+#include "bgp.h"
+#endif
+
+// Globals
+configt *config = NULL; // all configuration
+int tunfd = -1; // tun interface file handle. (network device)
+int udpfd = -1; // UDP file handle
+int controlfd = -1; // Control signal handle
+int clifd = -1; // Socket listening for CLI connections.
+int daefd = -1; // Socket listening for DAE connections.
+int snoopfd = -1; // UDP file handle for sending out intercept data
+int *radfds = NULL; // RADIUS requests file handles
+int ifrfd = -1; // File descriptor for routing, etc
+int ifr6fd = -1; // File descriptor for IPv6 routing, etc
+int rand_fd = -1; // Random data source
+int cluster_sockfd = -1; // Intra-cluster communications socket.
+int epollfd = -1; // event polling
+time_t basetime = 0; // base clock
+char hostname[1000] = ""; // us.
+static int tunidx; // ifr_ifindex of tun device
+static int syslog_log = 0; // are we logging to syslog
+static FILE *log_stream = 0; // file handle for direct logging (i.e. direct into file, not via syslog).
+uint32_t last_id = 0; // Unique ID for radius accounting
+
+// calculated from config->l2tp_mtu
+uint16_t MRU = 0; // PPP MRU
+uint16_t MSS = 0; // TCP MSS
+
+struct cli_session_actions *cli_session_actions = NULL; // Pending session changes requested by CLI
+struct cli_tunnel_actions *cli_tunnel_actions = NULL; // Pending tunnel changes required by CLI
+
+static void *ip_hash[256]; // Mapping from IP address to session structures.
+struct ipv6radix {
+ int sess;
+ struct ipv6radix *branch;
+} ipv6_hash[256]; // Mapping from IPv6 address to session structures.
+
+// Traffic counters.
+static uint32_t udp_rx = 0, udp_rx_pkt = 0, udp_tx = 0;
+static uint32_t eth_rx = 0, eth_rx_pkt = 0;
+uint32_t eth_tx = 0;
+
+static uint32_t ip_pool_size = 1; // Size of the pool of addresses used for dynamic address allocation.
+time_t time_now = 0; // Current time in seconds since epoch.
+static char time_now_string[64] = {0}; // Current time as a string.
+static int time_changed = 0; // time_now changed
+char main_quit = 0; // True if we're in the process of exiting.
+static char main_reload = 0; // Re-load pending
+linked_list *loaded_plugins;
+linked_list *plugins[MAX_PLUGIN_TYPES];
+
+#define membersize(STRUCT, MEMBER) sizeof(((STRUCT *)0)->MEMBER)
+#define CONFIG(NAME, MEMBER, TYPE) { NAME, offsetof(configt, MEMBER), membersize(configt, MEMBER), TYPE }
+
+config_descriptt config_values[] = {
+ CONFIG("debug", debug, INT),
+ CONFIG("log_file", log_filename, STRING),
+ CONFIG("pid_file", pid_file, STRING),
+ CONFIG("random_device", random_device, STRING),
+ CONFIG("l2tp_secret", l2tp_secret, STRING),
+ CONFIG("l2tp_mtu", l2tp_mtu, INT),
+ CONFIG("ppp_restart_time", ppp_restart_time, INT),
+ CONFIG("ppp_max_configure", ppp_max_configure, INT),
+ CONFIG("ppp_max_failure", ppp_max_failure, INT),
+ CONFIG("primary_dns", default_dns1, IPv4),
+ CONFIG("secondary_dns", default_dns2, IPv4),
+ CONFIG("primary_radius", radiusserver[0], IPv4),
+ CONFIG("secondary_radius", radiusserver[1], IPv4),
+ CONFIG("primary_radius_port", radiusport[0], SHORT),
+ CONFIG("secondary_radius_port", radiusport[1], SHORT),
+ CONFIG("radius_accounting", radius_accounting, BOOL),
+ CONFIG("radius_interim", radius_interim, INT),
+ CONFIG("radius_secret", radiussecret, STRING),
+ CONFIG("radius_authtypes", radius_authtypes_s, STRING),
+ CONFIG("radius_dae_port", radius_dae_port, SHORT),
+ CONFIG("allow_duplicate_users", allow_duplicate_users, BOOL),
+ CONFIG("bind_address", bind_address, IPv4),
+ CONFIG("peer_address", peer_address, IPv4),
+ CONFIG("send_garp", send_garp, BOOL),
+ CONFIG("throttle_speed", rl_rate, UNSIGNED_LONG),
+ CONFIG("throttle_buckets", num_tbfs, INT),
+ CONFIG("accounting_dir", accounting_dir, STRING),
+ CONFIG("setuid", target_uid, INT),
+ CONFIG("dump_speed", dump_speed, BOOL),
+ CONFIG("multi_read_count", multi_read_count, INT),
+ CONFIG("scheduler_fifo", scheduler_fifo, BOOL),
+ CONFIG("lock_pages", lock_pages, BOOL),
+ CONFIG("icmp_rate", icmp_rate, INT),
+ CONFIG("packet_limit", max_packets, INT),
+ CONFIG("cluster_address", cluster_address, IPv4),
+ CONFIG("cluster_interface", cluster_interface, STRING),
+ CONFIG("cluster_mcast_ttl", cluster_mcast_ttl, INT),
+ CONFIG("cluster_hb_interval", cluster_hb_interval, INT),
+ CONFIG("cluster_hb_timeout", cluster_hb_timeout, INT),
+ CONFIG("cluster_master_min_adv", cluster_master_min_adv, INT),
+ CONFIG("ipv6_prefix", ipv6_prefix, IPv6),
+ { NULL, 0, 0, 0 },
+};
+
+static char *plugin_functions[] = {
+ NULL,
+ "plugin_pre_auth",
+ "plugin_post_auth",
+ "plugin_packet_rx",
+ "plugin_packet_tx",
+ "plugin_timer",
+ "plugin_new_session",
+ "plugin_kill_session",
+ "plugin_control",
+ "plugin_radius_response",
+ "plugin_radius_reset",
+ "plugin_radius_account",
+ "plugin_become_master",
+ "plugin_new_session_master",
+};
+
+#define max_plugin_functions (sizeof(plugin_functions) / sizeof(char *))
+
+// Counters for shutdown sessions
+static sessiont shut_acct[8192];
+static sessionidt shut_acct_n = 0;
+
+tunnelt *tunnel = NULL; // Array of tunnel structures.
+sessiont *session = NULL; // Array of session structures.
+sessionlocalt *sess_local = NULL; // Array of local per-session counters.
+radiust *radius = NULL; // Array of radius structures.
+ippoolt *ip_address_pool = NULL; // Array of dynamic IP addresses.
+ip_filtert *ip_filters = NULL; // Array of named filters.
+static controlt *controlfree = 0;
+struct Tstats *_statistics = NULL;
+#ifdef RINGBUFFER
+struct Tringbuffer *ringbuffer = NULL;
+#endif
+
+static void cache_ipmap(in_addr_t ip, int s);
+static void uncache_ipmap(in_addr_t ip);
+static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s);
+static void free_ip_address(sessionidt s);
+static void dump_acct_info(int all);
+static void sighup_handler(int sig);
+static void shutdown_handler(int sig);
+static void sigchild_handler(int sig);
+static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response);
+static void update_config(void);
+static void read_config_file(void);
+static void initplugins(void);
+static int add_plugin(char *plugin_name);
+static int remove_plugin(char *plugin_name);
+static void plugins_done(void);
+static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen, struct in_addr *local);
+static tunnelidt new_tunnel(void);
+static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len);
+
+// on slaves, alow BGP to withdraw cleanly before exiting
+#define QUIT_DELAY 5
+
+// quit actions (master)
+#define QUIT_FAILOVER 1 // SIGTERM: exit when all control messages have been acked (for cluster failover)
+#define QUIT_SHUTDOWN 2 // SIGQUIT: shutdown sessions/tunnels, reject new connections
+
+// return internal time (10ths since process startup), set f if given
+// as a side-effect sets time_now, and time_changed
+static clockt now(double *f)
+{
+ struct timeval t;
+ gettimeofday(&t, 0);
+ if (f) *f = t.tv_sec + t.tv_usec / 1000000.0;
+ if (t.tv_sec != time_now)
+ {
+ time_now = t.tv_sec;
+ time_changed++;
+ }
+ return (t.tv_sec - basetime) * 10 + t.tv_usec / 100000 + 1;
+}
+
+// work out a retry time based on try number
+// This is a straight bounded exponential backoff.
+// Maximum re-try time is 32 seconds. (2^5).
+clockt backoff(uint8_t try)
+{
+ if (try > 5) try = 5; // max backoff
+ return now(NULL) + 10 * (1 << try);
+}
+
+
+//
+// Log a debug message. Typically called via the LOG macro
+//
+void _log(int level, sessionidt s, tunnelidt t, const char *format, ...)
+{
+ static char message[65536] = {0};
+ va_list ap;
+
+#ifdef RINGBUFFER
+ if (ringbuffer)
+ {
+ if (++ringbuffer->tail >= RINGBUFFER_SIZE)
+ ringbuffer->tail = 0;
+ if (ringbuffer->tail == ringbuffer->head)
+ if (++ringbuffer->head >= RINGBUFFER_SIZE)
+ ringbuffer->head = 0;
+
+ ringbuffer->buffer[ringbuffer->tail].level = level;
+ ringbuffer->buffer[ringbuffer->tail].session = s;
+ ringbuffer->buffer[ringbuffer->tail].tunnel = t;
+ va_start(ap, format);
+ vsnprintf(ringbuffer->buffer[ringbuffer->tail].message, 4095, format, ap);
+ va_end(ap);
+ }
+#endif
+
+ if (config->debug < level) return;
+
+ va_start(ap, format);
+ vsnprintf(message, sizeof(message), format, ap);
+
+ if (log_stream)
+ fprintf(log_stream, "%s %02d/%02d %s", time_now_string, t, s, message);
+ else if (syslog_log)
+ syslog(level + 2, "%02d/%02d %s", t, s, message); // We don't need LOG_EMERG or LOG_ALERT
+
+ va_end(ap);
+}
+
+void _log_hex(int level, const char *title, const uint8_t *data, int maxsize)
+{
+ int i, j;
+ const uint8_t *d = data;
+
+ if (config->debug < level) return;
+
+ // No support for _log_hex to syslog
+ if (log_stream)
+ {
+ _log(level, 0, 0, "%s (%d bytes):\n", title, maxsize);
+ setvbuf(log_stream, NULL, _IOFBF, 16384);
+
+ for (i = 0; i < maxsize; )
+ {
+ 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);
+ }
+
+ for (; j < i + 16; j++)
+ {
+ 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);
+ }
+
+ fflush(log_stream);
+ setbuf(log_stream, NULL);
+ }
+}
+
+// update a counter, accumulating 2^32 wraps
+void increment_counter(uint32_t *counter, uint32_t *wrap, uint32_t delta)
+{
+ uint32_t new = *counter + delta;
+ if (new < *counter)
+ (*wrap)++;
+
+ *counter = new;
+}
+
+// initialise the random generator
+static void initrandom(char *source)
+{
+ static char path[sizeof(config->random_device)] = "*undefined*";
+
+ // reinitialise only if we are forced to do so or if the config has changed
+ if (source && !strncmp(path, source, sizeof(path)))
+ return;
+
+ // close previous source, if any
+ if (rand_fd >= 0)
+ close(rand_fd);
+
+ rand_fd = -1;
+
+ if (source)
+ {
+ // register changes
+ snprintf(path, sizeof(path), "%s", source);
+
+ if (*path == '/')
+ {
+ rand_fd = open(path, O_RDONLY|O_NONBLOCK);
+ if (rand_fd < 0)
+ LOG(0, 0, 0, "Error opening the random device %s: %s\n",
+ path, strerror(errno));
+ }
+ }
+}
+
+// fill buffer with random data
+void random_data(uint8_t *buf, int len)
+{
+ int n = 0;
+
+ CSTAT(random_data);
+ if (rand_fd >= 0)
+ {
+ n = read(rand_fd, buf, len);
+ if (n >= len) return;
+ if (n < 0)
+ {
+ if (errno != EAGAIN)
+ {
+ LOG(0, 0, 0, "Error reading from random source: %s\n",
+ strerror(errno));
+
+ // fall back to rand()
+ initrandom(NULL);
+ }
+
+ n = 0;
+ }
+ }
+
+ // append missing data
+ while (n < len)
+ // not using the low order bits from the prng stream
+ buf[n++] = (rand() >> 4) & 0xff;
+}
+
+// Add a route
+//
+// This adds it to the routing table, advertises it
+// via BGP if enabled, and stuffs it into the
+// 'sessionbyip' cache.
+//
+// 'ip' and 'mask' must be in _host_ order.
+//
+static void routeset(sessionidt s, in_addr_t ip, in_addr_t mask, in_addr_t gw, int add)
+{
+ struct rtentry r;
+ int i;
+
+ if (!mask) mask = 0xffffffff;
+
+ ip &= mask; // Force the ip to be the first one in the route.
+
+ memset(&r, 0, sizeof(r));
+ r.rt_dev = config->tundevice;
+ r.rt_dst.sa_family = AF_INET;
+ *(uint32_t *) & (((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr) = htonl(ip);
+ r.rt_gateway.sa_family = AF_INET;
+ *(uint32_t *) & (((struct sockaddr_in *) &r.rt_gateway)->sin_addr.s_addr) = htonl(gw);
+ r.rt_genmask.sa_family = AF_INET;
+ *(uint32_t *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask);
+ r.rt_flags = (RTF_UP | RTF_STATIC);
+ if (gw)
+ r.rt_flags |= RTF_GATEWAY;
+ else if (mask == 0xffffffff)
+ r.rt_flags |= RTF_HOST;
+
+ LOG(1, s, 0, "Route %s %s/%s%s%s\n", add ? "add" : "del",
+ fmtaddr(htonl(ip), 0), fmtaddr(htonl(mask), 1),
+ gw ? " via" : "", gw ? fmtaddr(htonl(gw), 2) : "");
+
+ if (ioctl(ifrfd, add ? SIOCADDRT : SIOCDELRT, (void *) &r) < 0)
+ LOG(0, 0, 0, "routeset() error in ioctl: %s\n", strerror(errno));
+
+#ifdef BGP
+ if (add)
+ bgp_add_route(htonl(ip), htonl(mask));
+ else
+ bgp_del_route(htonl(ip), htonl(mask));
+#endif /* BGP */
+
+ // Add/Remove the IPs to the 'sessionbyip' cache.
+ // Note that we add the zero address in the case of
+ // a network route. Roll on CIDR.
+
+ // Note that 's == 0' implies this is the address pool.
+ // We still cache it here, because it will pre-fill
+ // the malloc'ed tree.
+
+ if (s)
+ {
+ if (!add) // Are we deleting a route?
+ s = 0; // Caching the session as '0' is the same as uncaching.
+
+ for (i = ip; (i&mask) == (ip&mask) ; ++i)
+ cache_ipmap(i, s);
+ }
+}
+
+void route6set(sessionidt s, struct in6_addr ip, int prefixlen, int add)
+{
+ struct in6_rtmsg rt;
+ char ipv6addr[INET6_ADDRSTRLEN];
+
+ if (ifr6fd < 0)
+ {
+ LOG(0, 0, 0, "Asked to set IPv6 route, but IPv6 not setup.\n");
+ return;
+ }
+
+ memset(&rt, 0, sizeof(rt));
+
+ memcpy(&rt.rtmsg_dst, &ip, sizeof(struct in6_addr));
+ rt.rtmsg_dst_len = prefixlen;
+ rt.rtmsg_metric = 1;
+ rt.rtmsg_flags = RTF_UP;
+ rt.rtmsg_ifindex = tunidx;
+
+ LOG(1, 0, 0, "Route %s %s/%d\n",
+ add ? "add" : "del",
+ inet_ntop(AF_INET6, &ip, ipv6addr, INET6_ADDRSTRLEN),
+ prefixlen);
+
+ if (ioctl(ifr6fd, add ? SIOCADDRT : SIOCDELRT, (void *) &rt) < 0)
+ LOG(0, 0, 0, "route6set() error in ioctl: %s\n",
+ strerror(errno));
+
+ // FIXME: need to add BGP routing (RFC2858)
+
+ if (s)
+ {
+ if (!add) // Are we deleting a route?
+ s = 0; // Caching the session as '0' is the same as uncaching.
+
+ cache_ipv6map(ip, prefixlen, s);
+ }
+
+ return;
+}
+
+// defined in linux/ipv6.h, but tricky to include from user-space
+// TODO: move routing to use netlink rather than ioctl
+struct in6_ifreq {
+ struct in6_addr ifr6_addr;
+ __u32 ifr6_prefixlen;
+ unsigned int ifr6_ifindex;
+};
+
+//
+// Set up TUN interface
+static void inittun(void)
+{
+ struct ifreq ifr;
+ struct in6_ifreq ifr6;
+ struct sockaddr_in sin = {0};
+ memset(&ifr, 0, sizeof(ifr));
+ ifr.ifr_flags = IFF_TUN;
+
+ tunfd = open(TUNDEVICE, O_RDWR);
+ if (tunfd < 0)
+ { // fatal
+ LOG(0, 0, 0, "Can't open %s: %s\n", TUNDEVICE, strerror(errno));
+ exit(1);
+ }
+ {
+ int flags = fcntl(tunfd, F_GETFL, 0);
+ fcntl(tunfd, F_SETFL, flags | O_NONBLOCK);
+ }
+ if (ioctl(tunfd, TUNSETIFF, (void *) &ifr) < 0)
+ {
+ LOG(0, 0, 0, "Can't set tun interface: %s\n", strerror(errno));
+ exit(1);
+ }
+ assert(strlen(ifr.ifr_name) < sizeof(config->tundevice));
+ strncpy(config->tundevice, ifr.ifr_name, sizeof(config->tundevice) - 1);
+ ifrfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
+
+ sin.sin_family = AF_INET;
+ sin.sin_addr.s_addr = 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)
+ {
+ LOG(0, 0, 0, "Error setting tun address: %s\n", strerror(errno));
+ exit(1);
+ }
+ /* Bump up the qlen to deal with bursts from the network */
+ ifr.ifr_qlen = 1000;
+ if (ioctl(ifrfd, SIOCSIFTXQLEN, (void *) &ifr) < 0)
+ {
+ LOG(0, 0, 0, "Error setting tun queue length: %s\n", strerror(errno));
+ exit(1);
+ }
+ /* set MTU to modem MRU */
+ ifr.ifr_mtu = MRU;
+ if (ioctl(ifrfd, SIOCSIFMTU, (void *) &ifr) < 0)
+ {
+ LOG(0, 0, 0, "Error setting tun MTU: %s\n", strerror(errno));
+ exit(1);
+ }
+ ifr.ifr_flags = IFF_UP;
+ if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0)
+ {
+ LOG(0, 0, 0, "Error setting tun flags: %s\n", strerror(errno));
+ exit(1);
+ }
+ if (ioctl(ifrfd, SIOCGIFINDEX, (void *) &ifr) < 0)
+ {
+ LOG(0, 0, 0, "Error getting tun ifindex: %s\n", strerror(errno));
+ exit(1);
+ }
+ tunidx = ifr.ifr_ifindex;
+
+ // Only setup IPv6 on the tun device if we have a configured prefix
+ if (config->ipv6_prefix.s6_addr[0]) {
+ ifr6fd = socket(PF_INET6, SOCK_DGRAM, 0);
+
+ // Link local address is FE80::1
+ memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
+ ifr6.ifr6_addr.s6_addr[0] = 0xFE;
+ ifr6.ifr6_addr.s6_addr[1] = 0x80;
+ ifr6.ifr6_addr.s6_addr[15] = 1;
+ ifr6.ifr6_prefixlen = 64;
+ ifr6.ifr6_ifindex = ifr.ifr_ifindex;
+ if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
+ {
+ LOG(0, 0, 0, "Error setting tun IPv6 link local address:"
+ " %s\n", strerror(errno));
+ }
+
+ // Global address is prefix::1
+ memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
+ ifr6.ifr6_addr = config->ipv6_prefix;
+ ifr6.ifr6_addr.s6_addr[15] = 1;
+ ifr6.ifr6_prefixlen = 64;
+ ifr6.ifr6_ifindex = ifr.ifr_ifindex;
+ if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
+ {
+ LOG(0, 0, 0, "Error setting tun IPv6 global address: %s\n",
+ strerror(errno));
+ }
+ }
+}
+
+// set up UDP ports
+static void initudp(void)
+{
+ int on = 1;
+ struct sockaddr_in addr;
+
+ // Tunnel
+ memset(&addr, 0, sizeof(addr));
+ addr.sin_family = AF_INET;
+ addr.sin_port = htons(L2TPPORT);
+ addr.sin_addr.s_addr = config->bind_address;
+ udpfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
+ setsockopt(udpfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
+ {
+ int flags = fcntl(udpfd, F_GETFL, 0);
+ fcntl(udpfd, F_SETFL, flags | O_NONBLOCK);
+ }
+ if (bind(udpfd, (void *) &addr, sizeof(addr)) < 0)
+ {
+ LOG(0, 0, 0, "Error in UDP bind: %s\n", strerror(errno));
+ exit(1);
+ }
+
+ // Control
+ memset(&addr, 0, sizeof(addr));
+ addr.sin_family = AF_INET;
+ addr.sin_port = htons(NSCTL_PORT);
+ controlfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
+ setsockopt(controlfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
+ setsockopt(controlfd, SOL_IP, IP_PKTINFO, &on, sizeof(on)); // recvfromto
+ if (bind(controlfd, (void *) &addr, sizeof(addr)) < 0)
+ {
+ LOG(0, 0, 0, "Error in control bind: %s\n", strerror(errno));
+ exit(1);
+ }
+
+ // Dynamic Authorization Extensions to RADIUS
+ memset(&addr, 0, sizeof(addr));
+ addr.sin_family = AF_INET;
+ addr.sin_port = htons(config->radius_dae_port);
+ daefd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
+ setsockopt(daefd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
+ setsockopt(daefd, SOL_IP, IP_PKTINFO, &on, sizeof(on)); // recvfromto
+ if (bind(daefd, (void *) &addr, sizeof(addr)) < 0)
+ {
+ LOG(0, 0, 0, "Error in DAE bind: %s\n", strerror(errno));
+ exit(1);
+ }
+
+ // Intercept
+ snoopfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
+}
+
+//
+// Find session by IP, < 1 for not found
+//
+// Confusingly enough, this 'ip' must be
+// in _network_ order. This being the common
+// case when looking it up from IP packet headers.
+//
+// We actually use this cache for two things.
+// #1. For used IP addresses, this maps to the
+// session ID that it's used by.
+// #2. For un-used IP addresses, this maps to the
+// index into the pool table that contains that
+// IP address.
+//
+
+static int lookup_ipmap(in_addr_t ip)
+{
+ uint8_t *a = (uint8_t *) &ip;
+ uint8_t **d = (uint8_t **) ip_hash;
+
+ if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
+ if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
+ if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
+
+ return (int) (intptr_t) d[(size_t) *a];
+}
+
+static int lookup_ipv6map(struct in6_addr ip)
+{
+ struct ipv6radix *curnode;
+ int i;
+ int s;
+ char ipv6addr[INET6_ADDRSTRLEN];
+
+ curnode = &ipv6_hash[ip.s6_addr[0]];
+ i = 1;
+ s = curnode->sess;
+
+ while (s == 0 && i < 15 && curnode->branch != NULL)
+ {
+ curnode = &curnode->branch[ip.s6_addr[i]];
+ s = curnode->sess;
+ i++;
+ }
+
+ LOG(4, s, session[s].tunnel, "Looking up address %s and got %d\n",
+ inet_ntop(AF_INET6, &ip, ipv6addr,
+ INET6_ADDRSTRLEN),
+ s);
+
+ return s;
+}
+
+sessionidt sessionbyip(in_addr_t ip)
+{
+ int s = lookup_ipmap(ip);
+ CSTAT(sessionbyip);
+
+ if (s > 0 && s < MAXSESSION && session[s].opened)
+ return (sessionidt) s;
+
+ return 0;
+}
+
+sessionidt sessionbyipv6(struct in6_addr ip)
+{
+ int s;
+ CSTAT(sessionbyipv6);
+
+ if (!memcmp(&config->ipv6_prefix, &ip, 8) ||
+ (ip.s6_addr[0] == 0xFE &&
+ ip.s6_addr[1] == 0x80 &&
+ ip.s6_addr16[1] == 0 &&
+ ip.s6_addr16[2] == 0 &&
+ ip.s6_addr16[3] == 0)) {
+ s = lookup_ipmap(*(in_addr_t *) &ip.s6_addr[8]);
+ } else {
+ s = lookup_ipv6map(ip);
+ }
+
+ if (s > 0 && s < MAXSESSION && session[s].opened)
+ return s;
+
+ return 0;
+}
+
+//
+// Take an IP address in HOST byte order and
+// add it to the sessionid by IP cache.
+//
+// (It's actually cached in network order)
+//
+static void cache_ipmap(in_addr_t ip, int s)
+{
+ in_addr_t nip = htonl(ip); // MUST be in network order. I.e. MSB must in be ((char *) (&ip))[0]
+ uint8_t *a = (uint8_t *) &nip;
+ uint8_t **d = (uint8_t **) ip_hash;
+ int i;
+
+ for (i = 0; i < 3; i++)
+ {
+ if (!d[(size_t) a[i]])
+ {
+ if (!(d[(size_t) a[i]] = calloc(256, sizeof(void *))))
+ return;
+ }
+
+ d = (uint8_t **) d[(size_t) a[i]];
+ }
+
+ d[(size_t) a[3]] = (uint8_t *) (intptr_t) s;
+
+ if (s > 0)
+ LOG(4, s, session[s].tunnel, "Caching ip address %s\n", fmtaddr(nip, 0));
+
+ else if (s == 0)
+ LOG(4, 0, 0, "Un-caching ip address %s\n", fmtaddr(nip, 0));
+ // else a map to an ip pool index.
+}
+
+static void uncache_ipmap(in_addr_t ip)
+{
+ cache_ipmap(ip, 0); // Assign it to the NULL session.
+}
+
+static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s)
+{
+ int i;
+ int bytes;
+ struct ipv6radix *curnode;
+ char ipv6addr[INET6_ADDRSTRLEN];
+
+ curnode = &ipv6_hash[ip.s6_addr[0]];
+
+ bytes = prefixlen >> 3;
+ i = 1;
+ while (i < bytes) {
+ if (curnode->branch == NULL)
+ {
+ if (!(curnode->branch = calloc(256,
+ sizeof (struct ipv6radix))))
+ return;
+ }
+ curnode = &curnode->branch[ip.s6_addr[i]];
+ i++;
+ }
+
+ curnode->sess = s;
+
+ if (s > 0)
+ LOG(4, s, session[s].tunnel, "Caching ip address %s/%d\n",
+ inet_ntop(AF_INET6, &ip, ipv6addr,
+ INET6_ADDRSTRLEN),
+ prefixlen);
+ else if (s == 0)
+ LOG(4, 0, 0, "Un-caching ip address %s/%d\n",
+ inet_ntop(AF_INET6, &ip, ipv6addr,
+ INET6_ADDRSTRLEN),
+ prefixlen);
+}
+
+//
+// CLI list to dump current ipcache.
+//
+int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc)
+{
+ char **d = (char **) ip_hash, **e, **f, **g;
+ int i, j, k, l;
+ int count = 0;
+
+ if (CLI_HELP_REQUESTED)
+ return CLI_HELP_NO_ARGS;
+
+ cli_print(cli, "%7s %s", "Sess#", "IP Address");
+
+ for (i = 0; i < 256; ++i)
+ {
+ if (!d[i])
+ continue;
+ e = (char **) d[i];
+ for (j = 0; j < 256; ++j)
+ {
+ if (!e[j])
+ continue;
+ f = (char **) e[j];
+ for (k = 0; k < 256; ++k)
+ {
+ if (!f[k])
+ continue;
+ g = (char **)f[k];
+ for (l = 0; l < 256; ++l)
+ {
+ if (!g[l])
+ continue;
+ cli_print(cli, "%7d %d.%d.%d.%d", (int) (intptr_t) g[l], i, j, k, l);
+ ++count;
+ }
+ }
+ }
+ }
+ cli_print(cli, "%d entries in cache", count);
+ return CLI_OK;
+}
+
+
+// Find session by username, 0 for not found
+// walled garden users aren't authenticated, so the username is
+// reasonably useless. Ignore them to avoid incorrect actions
+//
+// This is VERY inefficent. Don't call it often. :)
+//
+sessionidt sessionbyuser(char *username)
+{
+ int s;
+ CSTAT(sessionbyuser);
+
+ for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
+ {
+ if (!session[s].opened)
+ continue;
+
+ if (session[s].walled_garden)
+ continue; // Skip walled garden users.
+
+ if (!strncmp(session[s].user, username, 128))
+ return s;
+
+ }
+ return 0; // Not found.
+}
+
+void send_garp(in_addr_t ip)
+{
+ int s;
+ struct ifreq ifr;
+ uint8_t mac[6];
+
+ s = socket(PF_INET, SOCK_DGRAM, 0);
+ if (s < 0)
+ {
+ LOG(0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
+ return;
+ }
+ memset(&ifr, 0, sizeof(ifr));
+ strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
+ if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
+ {
+ LOG(0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
+ close(s);
+ return;
+ }
+ memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
+ if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
+ {
+ LOG(0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
+ close(s);
+ return;
+ }
+ close(s);
+ sendarp(ifr.ifr_ifindex, mac, ip);
+}
+
+static sessiont *sessiontbysessionidt(sessionidt s)
+{
+ if (!s || s >= MAXSESSION) return NULL;
+ return &session[s];
+}
+
+static sessionidt sessionidtbysessiont(sessiont *s)
+{
+ sessionidt val = s-session;
+ if (s < session || val >= MAXSESSION) return 0;
+ return val;
+}
+
+// actually send a control message for a specific tunnel
+void tunnelsend(uint8_t * buf, uint16_t l, tunnelidt t)
+{
+ struct sockaddr_in addr;
+
+ CSTAT(tunnelsend);
+
+ if (!t)
+ {
+ LOG(0, 0, t, "tunnelsend called with 0 as tunnel id\n");
+ STAT(tunnel_tx_errors);
+ return;
+ }
+
+ if (!tunnel[t].ip)
+ {
+ LOG(1, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
+ STAT(tunnel_tx_errors);
+ return;
+ }
+
+ memset(&addr, 0, sizeof(addr));
+ addr.sin_family = AF_INET;
+ *(uint32_t *) & addr.sin_addr = htonl(tunnel[t].ip);
+ addr.sin_port = htons(tunnel[t].port);
+
+ // sequence expected, if sequence in message
+ if (*buf & 0x08) *(uint16_t *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
+
+ // If this is a control message, deal with retries
+ if (*buf & 0x80)
+ {
+ tunnel[t].last = time_now; // control message sent
+ tunnel[t].retry = backoff(tunnel[t].try); // when to resend
+ if (tunnel[t].try)
+ {
+ STAT(tunnel_retries);
+ LOG(3, 0, t, "Control message resend try %d\n", tunnel[t].try);
+ }
+ }
+
+ if (sendto(udpfd, buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
+ {
+ LOG(0, ntohs((*(uint16_t *) (buf + 6))), t, "Error sending data out tunnel: %s (udpfd=%d, buf=%p, len=%d, dest=%s)\n",
+ strerror(errno), udpfd, buf, l, inet_ntoa(addr.sin_addr));
+ STAT(tunnel_tx_errors);
+ return;
+ }
+
+ LOG_HEX(5, "Send Tunnel Data", buf, l);
+ STAT(tunnel_tx_packets);
+ INC_STAT(tunnel_tx_bytes, l);
+}
+
+//
+// Tiny helper function to write data to
+// the 'tun' device.
+//
+int tun_write(uint8_t * data, int size)
+{
+ return write(tunfd, data, size);
+}
+
+// adjust tcp mss to avoid fragmentation (called only for tcp packets with syn set)
+void adjust_tcp_mss(sessionidt s, tunnelidt t, uint8_t *buf, int len, uint8_t *tcp)
+{
+ int d = (tcp[12] >> 4) * 4;
+ uint8_t *mss = 0;
+ uint8_t *opts;
+ uint8_t *data;
+ uint16_t orig;
+ uint32_t sum;
+
+ if ((tcp[13] & 0x3f) & ~(TCP_FLAG_SYN|TCP_FLAG_ACK)) // only want SYN and SYN,ACK
+ return;
+
+ if (tcp + d > buf + len) // short?
+ return;
+
+ opts = tcp + 20;
+ data = tcp + d;
+
+ while (opts < data)
+ {
+ if (*opts == 2 && opts[1] == 4) // mss option (2), length 4
+ {
+ mss = opts + 2;
+ if (mss + 2 > data) return; // short?
+ break;
+ }
+
+ if (*opts == 0) return; // end of options
+ if (*opts == 1 || !opts[1]) // no op (one byte), or no length (prevent loop)
+ opts++;
+ else
+ opts += opts[1]; // skip over option
+ }
+
+ if (!mss) return; // not found
+ orig = ntohs(*(uint16_t *) mss);
+
+ if (orig <= MSS) return; // mss OK
+
+ LOG(5, s, t, "TCP: %s:%u -> %s:%u SYN%s: adjusted mss from %u to %u\n",
+ fmtaddr(*(in_addr_t *) (buf + 12), 0), ntohs(*(uint16_t *) tcp),
+ fmtaddr(*(in_addr_t *) (buf + 16), 1), ntohs(*(uint16_t *) (tcp + 2)),
+ (tcp[13] & TCP_FLAG_ACK) ? ",ACK" : "", orig, MSS);
+
+ // set mss
+ *(int16_t *) mss = htons(MSS);
+
+ // adjust checksum (see rfc1141)
+ sum = orig + (~MSS & 0xffff);
+ sum += ntohs(*(uint16_t *) (tcp + 16));
+ sum = (sum & 0xffff) + (sum >> 16);
+ *(uint16_t *) (tcp + 16) = htons(sum + (sum >> 16));
+}
+
+// process outgoing (to tunnel) IP
+//
+static void processipout(uint8_t *buf, int len)
+{
+ sessionidt s;
+ sessiont *sp;
+ tunnelidt t;
+ in_addr_t ip;
+
+ uint8_t *data = buf; // Keep a copy of the originals.
+ int size = len;
+
+ uint8_t b[MAXETHER + 20];
+
+ CSTAT(processipout);
+
+ if (len < MIN_IP_SIZE)
+ {
+ LOG(1, 0, 0, "Short IP, %d bytes\n", len);
+ STAT(tun_rx_errors);
+ return;
+ }
+ if (len >= MAXETHER)
+ {
+ LOG(1, 0, 0, "Oversize IP packet %d bytes\n", len);
+ STAT(tun_rx_errors);
+ return;
+ }
+
+ // Skip the tun header
+ buf += 4;
+ len -= 4;
+
+ // Got an IP header now
+ if (*(uint8_t *)(buf) >> 4 != 4)
+ {
+ LOG(1, 0, 0, "IP: Don't understand anything except IPv4\n");
+ return;
+ }
+
+ ip = *(uint32_t *)(buf + 16);
+ if (!(s = sessionbyip(ip)))
+ {
+ // Is this a packet for a session that doesn't exist?
+ static int rate = 0; // Number of ICMP packets we've sent this second.
+ static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
+
+ if (last != time_now)
+ {
+ last = time_now;
+ rate = 0;
+ }
+
+ if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
+ {
+ LOG(4, 0, 0, "IP: Sending ICMP host unreachable to %s\n", fmtaddr(*(in_addr_t *)(buf + 12), 0));
+ host_unreachable(*(in_addr_t *)(buf + 12), *(uint16_t *)(buf + 4),
+ config->bind_address ? config->bind_address : my_address, buf, len);
+ }
+ return;
+ }
+ t = session[s].tunnel;
+ sp = &session[s];
+
+ // DoS prevention: enforce a maximum number of packets per 0.1s for a session
+ if (config->max_packets > 0)
+ {
+ if (sess_local[s].last_packet_out == TIME)
+ {
+ int max = config->max_packets;
+
+ // All packets for throttled sessions are handled by the
+ // master, so further limit by using the throttle rate.
+ // A bit of a kludge, since throttle rate is in kbps,
+ // but should still be generous given our average DSL
+ // packet size is 200 bytes: a limit of 28kbps equates
+ // to around 180 packets per second.
+ if (!config->cluster_iam_master && sp->throttle_out && sp->throttle_out < max)
+ max = sp->throttle_out;
+
+ if (++sess_local[s].packets_out > max)
+ {
+ sess_local[s].packets_dropped++;
+ return;
+ }
+ }
+ else
+ {
+ if (sess_local[s].packets_dropped)
+ {
+ INC_STAT(tun_rx_dropped, sess_local[s].packets_dropped);
+ LOG(3, s, t, "Dropped %u/%u packets to %s for %suser %s\n",
+ sess_local[s].packets_dropped, sess_local[s].packets_out,
+ fmtaddr(ip, 0), sp->throttle_out ? "throttled " : "",
+ sp->user);
+ }
+
+ sess_local[s].last_packet_out = TIME;
+ sess_local[s].packets_out = 1;
+ sess_local[s].packets_dropped = 0;
+ }
+ }
+
+ // run access-list if any
+ if (session[s].filter_out && !ip_filter(buf, len, session[s].filter_out - 1))
+ return;
+
+ // adjust MSS on SYN and SYN,ACK packets with options
+ if ((ntohs(*(uint16_t *) (buf + 6)) & 0x1fff) == 0 && buf[9] == IPPROTO_TCP) // first tcp fragment
+ {
+ int ihl = (buf[0] & 0xf) * 4; // length of IP header
+ if (len >= ihl + 20 && (buf[ihl + 13] & TCP_FLAG_SYN) && ((buf[ihl + 12] >> 4) > 5))
+ adjust_tcp_mss(s, t, buf, len, buf + ihl);
+ }
+
+ if (sp->tbf_out)
+ {
+ // Are we throttling this session?
+ if (config->cluster_iam_master)
+ tbf_queue_packet(sp->tbf_out, data, size);
+ else
+ master_throttle_packet(sp->tbf_out, data, size);
+ return;
+ }
+
+ if (sp->walled_garden && !config->cluster_iam_master)
+ {
+ // We are walled-gardening this
+ master_garden_packet(s, data, size);
+ return;
+ }
+
+ LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
+
+ // Add on L2TP header
+ {
+ uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIP);
+ if (!p) return;
+ tunnelsend(b, len + (p-b), t); // send it...
+ }
+
+ // Snooping this session, send it to intercept box
+ if (sp->snoop_ip && sp->snoop_port)
+ snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
+
+ increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
+ sp->cout_delta += len;
+ sp->pout++;
+ udp_tx += len;
+
+ sess_local[s].cout += len; // To send to master..
+ sess_local[s].pout++;
+}
+
+// process outgoing (to tunnel) IPv6
+//
+static void processipv6out(uint8_t * buf, int len)
+{
+ sessionidt s;
+ sessiont *sp;
+ tunnelidt t;
+ in_addr_t ip;
+ struct in6_addr ip6;
+
+ uint8_t *data = buf; // Keep a copy of the originals.
+ int size = len;
+
+ uint8_t b[MAXETHER + 20];
+
+ CSTAT(processipv6out);
+
+ if (len < MIN_IP_SIZE)
+ {
+ LOG(1, 0, 0, "Short IPv6, %d bytes\n", len);
+ STAT(tunnel_tx_errors);
+ return;
+ }
+ if (len >= MAXETHER)
+ {
+ LOG(1, 0, 0, "Oversize IPv6 packet %d bytes\n", len);
+ STAT(tunnel_tx_errors);
+ return;
+ }
+
+ // Skip the tun header
+ buf += 4;
+ len -= 4;
+
+ // Got an IP header now
+ if (*(uint8_t *)(buf) >> 4 != 6)
+ {
+ LOG(1, 0, 0, "IP: Don't understand anything except IPv6\n");
+ return;
+ }
+
+ ip6 = *(struct in6_addr *)(buf+24);
+ s = sessionbyipv6(ip6);
+
+ if (s == 0)
+ {
+ ip = *(uint32_t *)(buf + 32);
+ s = sessionbyip(ip);
+ }
+
+ if (s == 0)
+ {
+ // Is this a packet for a session that doesn't exist?
+ static int rate = 0; // Number of ICMP packets we've sent this second.
+ static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
+
+ if (last != time_now)
+ {
+ last = time_now;
+ rate = 0;
+ }
+
+ if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
+ {
+ // FIXME: Should send icmp6 host unreachable
+ }
+ return;
+ }
+ t = session[s].tunnel;
+ sp = &session[s];
+
+ // FIXME: add DoS prevention/filters?
+
+ if (sp->tbf_out)
+ {
+ // Are we throttling this session?
+ if (config->cluster_iam_master)
+ tbf_queue_packet(sp->tbf_out, data, size);
+ else
+ master_throttle_packet(sp->tbf_out, data, size);
+ return;
+ }
+ else if (sp->walled_garden && !config->cluster_iam_master)
+ {
+ // We are walled-gardening this
+ master_garden_packet(s, data, size);
+ return;
+ }
+
+ LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
+
+ // Add on L2TP header
+ {
+ uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIPV6);
+ if (!p) return;
+ tunnelsend(b, len + (p-b), t); // send it...
+ }
+
+ // Snooping this session, send it to intercept box
+ if (sp->snoop_ip && sp->snoop_port)
+ snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
+
+ increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
+ sp->cout_delta += len;
+ sp->pout++;
+ udp_tx += len;
+
+ sess_local[s].cout += len; // To send to master..
+ sess_local[s].pout++;
+}
+
+//
+// Helper routine for the TBF filters.
+// Used to send queued data in to the user!
+//
+static void send_ipout(sessionidt s, uint8_t *buf, int len)
+{
+ sessiont *sp;
+ tunnelidt t;
+ in_addr_t ip;
+
+ uint8_t b[MAXETHER + 20];
+
+ if (len < 0 || len > MAXETHER)
+ {
+ LOG(1, 0, 0, "Odd size IP packet: %d bytes\n", len);
+ return;
+ }
+
+ // Skip the tun header
+ buf += 4;
+ len -= 4;
+
+ ip = *(in_addr_t *)(buf + 16);
+
+ if (!session[s].ip)
+ return;
+
+ t = session[s].tunnel;
+ sp = &session[s];
+
+ LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
+
+ // Add on L2TP header
+ {
+ uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIP);
+ if (!p) return;
+ tunnelsend(b, len + (p-b), t); // send it...
+ }
+
+ // Snooping this session.
+ if (sp->snoop_ip && sp->snoop_port)
+ snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
+
+ increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
+ sp->cout_delta += len;
+ sp->pout++;
+ udp_tx += len;
+
+ sess_local[s].cout += len; // To send to master..
+ sess_local[s].pout++;
+}
+
+// add an AVP (16 bit)
+static void control16(controlt * c, uint16_t avp, uint16_t val, uint8_t m)
+{
+ uint16_t l = (m ? 0x8008 : 0x0008);
+ *(uint16_t *) (c->buf + c->length + 0) = htons(l);
+ *(uint16_t *) (c->buf + c->length + 2) = htons(0);
+ *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
+ *(uint16_t *) (c->buf + c->length + 6) = htons(val);
+ c->length += 8;
+}
+
+// add an AVP (32 bit)
+static void control32(controlt * c, uint16_t avp, uint32_t val, uint8_t m)
+{
+ uint16_t l = (m ? 0x800A : 0x000A);
+ *(uint16_t *) (c->buf + c->length + 0) = htons(l);
+ *(uint16_t *) (c->buf + c->length + 2) = htons(0);
+ *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
+ *(uint32_t *) (c->buf + c->length + 6) = htonl(val);
+ c->length += 10;
+}
+
+// add an AVP (string)
+static void controls(controlt * c, uint16_t avp, char *val, uint8_t m)
+{
+ uint16_t l = ((m ? 0x8000 : 0) + strlen(val) + 6);
+ *(uint16_t *) (c->buf + c->length + 0) = htons(l);
+ *(uint16_t *) (c->buf + c->length + 2) = htons(0);
+ *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
+ memcpy(c->buf + c->length + 6, val, strlen(val));
+ c->length += 6 + strlen(val);
+}
+
+// add a binary AVP
+static void controlb(controlt * c, uint16_t avp, uint8_t *val, unsigned int len, uint8_t m)
+{
+ uint16_t l = ((m ? 0x8000 : 0) + len + 6);
+ *(uint16_t *) (c->buf + c->length + 0) = htons(l);
+ *(uint16_t *) (c->buf + c->length + 2) = htons(0);
+ *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
+ memcpy(c->buf + c->length + 6, val, len);
+ c->length += 6 + len;
+}
+
+// new control connection
+static controlt *controlnew(uint16_t mtype)
+{
+ controlt *c;
+ if (!controlfree)
+ c = malloc(sizeof(controlt));
+ else
+ {
+ c = controlfree;
+ controlfree = c->next;
+ }
+ assert(c);
+ c->next = 0;
+ *(uint16_t *) (c->buf + 0) = htons(0xC802); // flags/ver
+ c->length = 12;
+ control16(c, 0, mtype, 1);
+ return c;
+}
+
+// send zero block if nothing is waiting
+// (ZLB send).
+static void controlnull(tunnelidt t)
+{
+ uint8_t buf[12];
+ if (tunnel[t].controlc) // Messages queued; They will carry the ack.
+ return;
+
+ *(uint16_t *) (buf + 0) = htons(0xC802); // flags/ver
+ *(uint16_t *) (buf + 2) = htons(12); // length
+ *(uint16_t *) (buf + 4) = htons(tunnel[t].far); // tunnel
+ *(uint16_t *) (buf + 6) = htons(0); // session
+ *(uint16_t *) (buf + 8) = htons(tunnel[t].ns); // sequence
+ *(uint16_t *) (buf + 10) = htons(tunnel[t].nr); // sequence
+ tunnelsend(buf, 12, t);
+}
+
+// add a control message to a tunnel, and send if within window
+static void controladd(controlt *c, sessionidt far, tunnelidt t)
+{
+ *(uint16_t *) (c->buf + 2) = htons(c->length); // length
+ *(uint16_t *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
+ *(uint16_t *) (c->buf + 6) = htons(far); // session
+ *(uint16_t *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
+ tunnel[t].ns++; // advance sequence
+ // link in message in to queue
+ if (tunnel[t].controlc)
+ tunnel[t].controle->next = c;
+ else
+ tunnel[t].controls = c;
+
+ tunnel[t].controle = c;
+ tunnel[t].controlc++;
+
+ // send now if space in window
+ if (tunnel[t].controlc <= tunnel[t].window)
+ {
+ tunnel[t].try = 0; // first send
+ tunnelsend(c->buf, c->length, t);
+ }
+}
+
+//
+// Throttle or Unthrottle a session
+//
+// Throttle the data from/to through a session to no more than
+// 'rate_in' kbit/sec in (from user) or 'rate_out' kbit/sec out (to
+// user).
+//
+// If either value is -1, the current value is retained for that
+// direction.
+//
+void throttle_session(sessionidt s, int rate_in, int rate_out)
+{
+ if (!session[s].opened)
+ return; // No-one home.
+
+ if (!*session[s].user)
+ return; // User not logged in
+
+ if (rate_in >= 0)
+ {
+ int bytes = rate_in * 1024 / 8; // kbits to bytes
+ if (session[s].tbf_in)
+ free_tbf(session[s].tbf_in);
+
+ if (rate_in > 0)
+ session[s].tbf_in = new_tbf(s, bytes * 2, bytes, send_ipin);
+ else
+ session[s].tbf_in = 0;
+
+ session[s].throttle_in = rate_in;
+ }
+
+ if (rate_out >= 0)
+ {
+ int bytes = rate_out * 1024 / 8;
+ if (session[s].tbf_out)
+ free_tbf(session[s].tbf_out);
+
+ if (rate_out > 0)
+ session[s].tbf_out = new_tbf(s, bytes * 2, bytes, send_ipout);
+ else
+ session[s].tbf_out = 0;
+
+ session[s].throttle_out = rate_out;
+ }
+}
+
+// add/remove filters from session (-1 = no change)
+void filter_session(sessionidt s, int filter_in, int filter_out)
+{
+ if (!session[s].opened)
+ return; // No-one home.
+
+ if (!*session[s].user)
+ return; // User not logged in
+
+ // paranoia
+ if (filter_in > MAXFILTER) filter_in = -1;
+ if (filter_out > MAXFILTER) filter_out = -1;
+ if (session[s].filter_in > MAXFILTER) session[s].filter_in = 0;
+ if (session[s].filter_out > MAXFILTER) session[s].filter_out = 0;
+
+ if (filter_in >= 0)
+ {
+ if (session[s].filter_in)
+ ip_filters[session[s].filter_in - 1].used--;
+
+ if (filter_in > 0)
+ ip_filters[filter_in - 1].used++;
+
+ session[s].filter_in = filter_in;
+ }
+
+ if (filter_out >= 0)
+ {
+ if (session[s].filter_out)
+ ip_filters[session[s].filter_out - 1].used--;
+
+ if (filter_out > 0)
+ ip_filters[filter_out - 1].used++;
+
+ session[s].filter_out = filter_out;
+ }
+}
+
+// start tidy shutdown of session
+void sessionshutdown(sessionidt s, char const *reason, int cdn_result, int cdn_error, int term_cause)
+{
+ int walled_garden = session[s].walled_garden;
+
+
+ CSTAT(sessionshutdown);
+
+ if (!session[s].opened)
+ {
+ LOG(3, s, session[s].tunnel, "Called sessionshutdown on an unopened session.\n");
+ return; // not a live session
+ }
+
+ if (!session[s].die)
+ {
+ struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
+ LOG(2, s, session[s].tunnel, "Shutting down session %d: %s\n", s, reason);
+ run_plugins(PLUGIN_KILL_SESSION, &data);
+ }
+
+ if (session[s].ip && !walled_garden && !session[s].die)
+ {
+ // RADIUS Stop message
+ uint16_t r = radiusnew(s);
+ if (r)
+ {
+ // stop, if not already trying
+ if (radius[r].state != RADIUSSTOP)
+ {
+ radius[r].term_cause = term_cause;
+ radius[r].term_msg = reason;
+ radiussend(r, RADIUSSTOP);
+ }
+ }
+ else
+ LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
+
+ // Save counters to dump to accounting file
+ if (*config->accounting_dir && shut_acct_n < sizeof(shut_acct) / sizeof(*shut_acct))
+ memcpy(&shut_acct[shut_acct_n++], &session[s], sizeof(session[s]));
+ }
+
+ if (session[s].ip)
+ { // IP allocated, clear and unroute
+ int r;
+ int routed = 0;
+ for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
+ {
+ if ((session[s].ip & session[s].route[r].mask) ==
+ (session[s].route[r].ip & session[s].route[r].mask))
+ routed++;
+
+ routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 0);
+ session[s].route[r].ip = 0;
+ }
+
+ if (session[s].ip_pool_index == -1) // static ip
+ {
+ if (!routed) routeset(s, session[s].ip, 0, 0, 0);
+ session[s].ip = 0;
+ }
+ else
+ free_ip_address(s);
+
+ // unroute IPv6, if setup
+ if (session[s].ppp.ipv6cp == Opened && session[s].ipv6prefixlen)
+ route6set(s, session[s].ipv6route, session[s].ipv6prefixlen, 0);
+ }
+
+ if (session[s].throttle_in || session[s].throttle_out) // Unthrottle if throttled.
+ throttle_session(s, 0, 0);
+
+ if (cdn_result)
+ { // Send CDN
+ controlt *c = controlnew(14); // sending CDN
+ if (cdn_error)
+ {
+ uint8_t buf[4];
+ *(uint16_t *) buf = htons(cdn_result);
+ *(uint16_t *) (buf+2) = htons(cdn_error);
+ controlb(c, 1, buf, 4, 1);
+ }
+ else
+ control16(c, 1, cdn_result, 1);
+
+ control16(c, 14, s, 1); // assigned session (our end)
+ controladd(c, session[s].far, session[s].tunnel); // send the message
+ }
+
+ if (!session[s].die)
+ session[s].die = TIME + 150; // Clean up in 15 seconds
+
+ // update filter refcounts
+ if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
+ if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
+
+ // clear PPP state
+ memset(&session[s].ppp, 0, sizeof(session[s].ppp));
+ sess_local[s].lcp.restart = 0;
+ sess_local[s].ipcp.restart = 0;
+ sess_local[s].ipv6cp.restart = 0;
+ sess_local[s].ccp.restart = 0;
+
+ cluster_send_session(s);
+}
+
+void sendipcp(sessionidt s, tunnelidt t)
+{
+ uint8_t buf[MAXETHER];
+ uint8_t *q;
+
+ CSTAT(sendipcp);
+ LOG(3, s, t, "IPCP: send ConfigReq\n");
+
+ if (!session[s].unique_id)
+ {
+ if (!++last_id) ++last_id; // skip zero
+ session[s].unique_id = last_id;
+ }
+
+ q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPIPCP);
+ if (!q) return;
+
+ *q = ConfigReq;
+ q[1] = session[s].unique_id & 0xf; // ID, dont care, we only send one type of request
+ *(uint16_t *) (q + 2) = htons(10); // packet length
+ q[4] = 3; // ip address option
+ q[5] = 6; // option length
+ *(in_addr_t *) (q + 6) = config->peer_address ? config->peer_address :
+ config->bind_address ? config->bind_address :
+ my_address; // send my IP
+
+ tunnelsend(buf, 10 + (q - buf), t); // send it
+ restart_timer(s, ipcp);
+}
+
+void sendipv6cp(sessionidt s, tunnelidt t)
+{
+ uint8_t buf[MAXETHER];
+ uint8_t *q;
+
+ CSTAT(sendipv6cp);
+ LOG(3, s, t, "IPV6CP: send ConfigReq\n");
+
+ q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPIPV6CP);
+ if (!q) return;
+
+ *q = ConfigReq;
+ q[1] = session[s].unique_id & 0xf; // ID, don't care, we
+ // only send one type
+ // of request
+ *(uint16_t *) (q + 2) = htons(14);
+ q[4] = 1; // interface identifier option
+ q[5] = 10; // option length
+ *(uint32_t *) (q + 6) = 0; // We'll be prefix::1
+ *(uint32_t *) (q + 10) = 0;
+ q[13] = 1;
+
+ tunnelsend(buf, 14 + (q - buf), t); // send it
+ restart_timer(s, ipv6cp);
+}
+
+static void sessionclear(sessionidt s)
+{
+ memset(&session[s], 0, sizeof(session[s]));
+ memset(&sess_local[s], 0, sizeof(sess_local[s]));
+ memset(&cli_session_actions[s], 0, sizeof(cli_session_actions[s]));
+
+ session[s].tunnel = T_FREE; // Mark it as free.
+ session[s].next = sessionfree;
+ sessionfree = s;
+}
+
+// kill a session now
+void sessionkill(sessionidt s, char *reason)
+{
+
+ CSTAT(sessionkill);
+
+ if (!session[s].opened) // not alive
+ return;
+
+ if (session[s].next)
+ {
+ LOG(0, s, session[s].tunnel, "Tried to kill a session with next pointer set (%d)\n", session[s].next);
+ return;
+ }
+
+ session[s].die = TIME;
+ sessionshutdown(s, reason, CDN_ADMIN_DISC, TERM_ADMIN_RESET); // close radius/routes, etc.
+ if (sess_local[s].radius)
+ radiusclear(sess_local[s].radius, s); // cant send clean accounting data, session is killed
+
+ LOG(2, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
+ sessionclear(s);
+ cluster_send_session(s);
+}
+
+static void tunnelclear(tunnelidt t)
+{
+ if (!t) return;
+ memset(&tunnel[t], 0, sizeof(tunnel[t]));
+ tunnel[t].state = TUNNELFREE;
+}
+
+// kill a tunnel now
+static void tunnelkill(tunnelidt t, char *reason)
+{
+ sessionidt s;
+ controlt *c;
+
+ CSTAT(tunnelkill);
+
+ tunnel[t].state = TUNNELDIE;
+
+ // free control messages
+ while ((c = tunnel[t].controls))
+ {
+ controlt * n = c->next;
+ tunnel[t].controls = n;
+ tunnel[t].controlc--;
+ c->next = controlfree;
+ controlfree = c;
+ }
+ // kill sessions
+ for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
+ if (session[s].tunnel == t)
+ sessionkill(s, reason);
+
+ // free tunnel
+ tunnelclear(t);
+ LOG(1, 0, t, "Kill tunnel %d: %s\n", t, reason);
+ cli_tunnel_actions[t].action = 0;
+ cluster_send_tunnel(t);
+}
+
+// shut down a tunnel cleanly
+static void tunnelshutdown(tunnelidt t, char *reason, int result, int error, char *msg)
+{
+ sessionidt s;
+
+ CSTAT(tunnelshutdown);
+
+ if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
+ {
+ // never set up, can immediately kill
+ tunnelkill(t, reason);
+ return;
+ }
+ LOG(1, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
+
+ // close session
+ for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
+ if (session[s].tunnel == t)
+ sessionshutdown(s, reason, CDN_NONE, TERM_ADMIN_RESET);
+
+ tunnel[t].state = TUNNELDIE;
+ tunnel[t].die = TIME + 700; // Clean up in 70 seconds
+ cluster_send_tunnel(t);
+ // TBA - should we wait for sessions to stop?
+ if (result)
+ {
+ controlt *c = controlnew(4); // sending StopCCN
+ if (error)
+ {
+ uint8_t buf[64];
+ int l = 4;
+ *(uint16_t *) buf = htons(result);
+ *(uint16_t *) (buf+2) = htons(error);
+ if (msg)
+ {
+ int m = strlen(msg);
+ if (m + 4 > sizeof(buf))
+ m = sizeof(buf) - 4;
+
+ memcpy(buf+4, msg, m);
+ l += m;
+ }
+
+ controlb(c, 1, buf, l, 1);
+ }
+ else
+ control16(c, 1, result, 1);
+
+ control16(c, 9, t, 1); // assigned tunnel (our end)
+ controladd(c, 0, t); // send the message
+ }
+}
+
+// read and process packet on tunnel (UDP)
+void processudp(uint8_t *buf, int len, struct sockaddr_in *addr)
+{
+ uint8_t *chapresponse = NULL;
+ uint16_t l = len, t = 0, s = 0, ns = 0, nr = 0;
+ uint8_t *p = buf + 2;
+
+
+ CSTAT(processudp);
+
+ udp_rx += len;
+ udp_rx_pkt++;
+ LOG_HEX(5, "UDP Data", buf, len);
+ STAT(tunnel_rx_packets);
+ INC_STAT(tunnel_rx_bytes, len);
+ if (len < 6)
+ {
+ LOG(1, 0, 0, "Short UDP, %d bytes\n", len);
+ STAT(tunnel_rx_errors);
+ return;
+ }
+ if ((buf[1] & 0x0F) != 2)
+ {
+ LOG(1, 0, 0, "Bad L2TP ver %d\n", (buf[1] & 0x0F) != 2);
+ STAT(tunnel_rx_errors);
+ return;
+ }
+ if (*buf & 0x40)
+ { // length
+ l = ntohs(*(uint16_t *) p);
+ p += 2;
+ }
+ t = ntohs(*(uint16_t *) p);
+ p += 2;
+ s = ntohs(*(uint16_t *) p);
+ p += 2;
+ if (s >= MAXSESSION)
+ {
+ LOG(1, s, t, "Received UDP packet with invalid session ID\n");
+ STAT(tunnel_rx_errors);
+ return;
+ }
+ if (t >= MAXTUNNEL)
+ {
+ LOG(1, s, t, "Received UDP packet with invalid tunnel ID\n");
+ STAT(tunnel_rx_errors);
+ return;
+ }
+ if (*buf & 0x08)
+ { // ns/nr
+ ns = ntohs(*(uint16_t *) p);
+ p += 2;
+ nr = ntohs(*(uint16_t *) p);
+ p += 2;
+ }
+ if (*buf & 0x02)
+ { // offset
+ uint16_t o = ntohs(*(uint16_t *) p);
+ p += o + 2;
+ }
+ if ((p - buf) > l)
+ {
+ LOG(1, s, t, "Bad length %d>%d\n", (int) (p - buf), l);
+ STAT(tunnel_rx_errors);
+ return;
+ }
+ l -= (p - buf);
+
+ // used to time out old tunnels
+ if (t && tunnel[t].state == TUNNELOPEN)
+ tunnel[t].lastrec = time_now;
+
+ if (*buf & 0x80)
+ { // control
+ uint16_t message = 0xFFFF; // message type
+ uint8_t fatal = 0;
+ uint8_t mandatory = 0;
+ uint16_t asession = 0; // assigned session
+ uint32_t amagic = 0; // magic number
+ uint8_t aflags = 0; // flags from last LCF
+ uint16_t version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
+ char called[MAXTEL] = ""; // called number
+ char calling[MAXTEL] = ""; // calling number
+
+ if (!config->cluster_iam_master)
+ {
+ master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
+ return;
+ }
+
+ // control messages must have bits 0x80|0x40|0x08
+ // (type, length and sequence) set, and bits 0x02|0x01
+ // (offset and priority) clear
+ if ((*buf & 0xCB) != 0xC8)
+ {
+ LOG(1, s, t, "Bad control header %02X\n", *buf);
+ STAT(tunnel_rx_errors);
+ return;
+ }
+
+ // check for duplicate tunnel open message
+ if (!t && ns == 0)
+ {
+ int i;
+
+ //
+ // Is this a duplicate of the first packet? (SCCRQ)
+ //
+ for (i = 1; i <= config->cluster_highest_tunnelid ; ++i)
+ {
+ if (tunnel[i].state != TUNNELOPENING ||
+ tunnel[i].ip != ntohl(*(in_addr_t *) & addr->sin_addr) ||
+ tunnel[i].port != ntohs(addr->sin_port) )
+ continue;
+ t = i;
+ LOG(3, s, t, "Duplicate SCCRQ?\n");
+ break;
+ }
+ }
+
+ LOG(3, s, t, "Control message (%d bytes): (unacked %d) l-ns %d l-nr %d r-ns %d r-nr %d\n",
+ l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
+
+ // if no tunnel specified, assign one
+ if (!t)
+ {
+ if (!(t = new_tunnel()))
+ {
+ LOG(1, 0, 0, "No more tunnels\n");
+ STAT(tunnel_overflow);
+ return;
+ }
+ tunnelclear(t);
+ tunnel[t].ip = ntohl(*(in_addr_t *) & addr->sin_addr);
+ tunnel[t].port = ntohs(addr->sin_port);
+ tunnel[t].window = 4; // default window
+ STAT(tunnel_created);
+ LOG(1, 0, t, " New tunnel from %s:%u ID %d\n",
+ fmtaddr(htonl(tunnel[t].ip), 0), tunnel[t].port, t);
+ }
+
+ // If the 'ns' just received is not the 'nr' we're
+ // expecting, just send an ack and drop it.
+ //
+ // if 'ns' is less, then we got a retransmitted packet.
+ // if 'ns' is greater than missed a packet. Either way
+ // we should ignore it.
+ if (ns != tunnel[t].nr)
+ {
+ // is this the sequence we were expecting?
+ STAT(tunnel_rx_errors);
+ LOG(1, 0, t, " Out of sequence tunnel %d, (%d is not the expected %d)\n",
+ t, ns, tunnel[t].nr);
+
+ if (l) // Is this not a ZLB?
+ controlnull(t);
+ return;
+ }
+
+ // check sequence of this message
+ {
+ int skip = tunnel[t].window; // track how many in-window packets are still in queue
+ // some to clear maybe?
+ while (tunnel[t].controlc > 0 && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
+ {
+ controlt *c = tunnel[t].controls;
+ tunnel[t].controls = c->next;
+ tunnel[t].controlc--;
+ c->next = controlfree;
+ controlfree = c;
+ skip--;
+ tunnel[t].try = 0; // we have progress
+ }
+
+ // receiver advance (do here so quoted correctly in any sends below)
+ if (l) tunnel[t].nr = (ns + 1);
+ if (skip < 0) skip = 0;
+ if (skip < tunnel[t].controlc)
+ {
+ // 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)
+ {
+ c = c->next;
+ skip--;
+ }
+ while (c && tosend)
+ {
+ tunnel[t].try = 0; // first send
+ tunnelsend(c->buf, c->length, t);
+ c = c->next;
+ tosend--;
+ }
+ }
+ if (!tunnel[t].controlc)
+ tunnel[t].retry = 0; // caught up
+ }
+ if (l)
+ { // if not a null message
+ int result = 0;
+ int error = 0;
+ char *msg = 0;
+
+ // Default disconnect cause/message on receipt of CDN. Set to
+ // more specific value from attribute 1 (result code) or 46
+ // (disconnect cause) if present below.
+ int disc_cause_set = 0;
+ int disc_cause = TERM_NAS_REQUEST;
+ char const *disc_reason = "Closed (Received CDN).";
+
+ // process AVPs
+ while (l && !(fatal & 0x80)) // 0x80 = mandatory AVP
+ {
+ uint16_t n = (ntohs(*(uint16_t *) p) & 0x3FF);
+ uint8_t *b = p;
+ uint8_t flags = *p;
+ uint16_t mtype;
+
+ if (n > l)
+ {
+ LOG(1, s, t, "Invalid length in AVP\n");
+ STAT(tunnel_rx_errors);
+ return;
+ }
+ p += n; // next
+ l -= n;
+ if (flags & 0x3C) // reserved bits, should be clear
+ {
+ LOG(1, s, t, "Unrecognised AVP flags %02X\n", *b);
+ fatal = flags;
+ result = 2; // general error
+ error = 3; // reserved field non-zero
+ msg = 0;
+ continue; // next
+ }
+ b += 2;
+ if (*(uint16_t *) (b))
+ {
+ LOG(2, s, t, "Unknown AVP vendor %d\n", ntohs(*(uint16_t *) (b)));
+ fatal = flags;
+ result = 2; // general error
+ error = 6; // generic vendor-specific error
+ msg = "unsupported vendor-specific";
+ continue; // next
+ }
+ b += 2;
+ mtype = ntohs(*(uint16_t *) (b));
+ b += 2;
+ n -= 6;
+
+ if (flags & 0x40)
+ {
+ uint16_t orig_len;
+
+ // handle hidden AVPs
+ if (!*config->l2tp_secret)
+ {
+ LOG(1, s, t, "Hidden AVP requested, but no L2TP secret.\n");
+ fatal = flags;
+ result = 2; // general error
+ error = 6; // generic vendor-specific error
+ msg = "secret not specified";
+ continue;
+ }
+ if (!session[s].random_vector_length)
+ {
+ LOG(1, s, t, "Hidden AVP requested, but no random vector.\n");
+ fatal = flags;
+ result = 2; // general error
+ error = 6; // generic
+ msg = "no random vector";
+ continue;
+ }
+ if (n < 8)
+ {
+ LOG(2, s, t, "Short hidden AVP.\n");
+ fatal = flags;
+ result = 2; // general error
+ error = 2; // length is wrong
+ msg = 0;
+ continue;
+ }
+
+ // Unhide the AVP
+ unhide_value(b, n, mtype, session[s].random_vector, session[s].random_vector_length);
+
+ orig_len = ntohs(*(uint16_t *) b);
+ if (orig_len > n + 2)
+ {
+ LOG(1, s, t, "Original length %d too long in hidden AVP of length %d; wrong secret?\n",
+ orig_len, n);
+
+ fatal = flags;
+ result = 2; // general error
+ error = 2; // length is wrong
+ msg = 0;
+ continue;
+ }
+
+ b += 2;
+ n = orig_len;
+ }
+
+ LOG(4, s, t, " AVP %d (%s) len %d%s%s\n", mtype, l2tp_avp_name(mtype), n,
+ flags & 0x40 ? ", hidden" : "", flags & 0x80 ? ", mandatory" : "");
+
+ switch (mtype)
+ {
+ case 0: // message type
+ message = ntohs(*(uint16_t *) b);
+ mandatory = flags & 0x80;
+ LOG(4, s, t, " Message type = %d (%s)\n", *b, l2tp_code(message));
+ break;
+ case 1: // result code
+ {
+ uint16_t rescode = ntohs(*(uint16_t *) b);
+ char const *resdesc = "(unknown)";
+ char const *errdesc = NULL;
+ int cause = 0;
+
+ if (message == 4)
+ { /* StopCCN */
+ resdesc = l2tp_stopccn_result_code(rescode);
+ cause = TERM_LOST_SERVICE;
+ }
+ else if (message == 14)
+ { /* CDN */
+ resdesc = l2tp_cdn_result_code(rescode);
+ if (rescode == 1)
+ cause = TERM_LOST_CARRIER;
+ else
+ cause = TERM_ADMIN_RESET;
+ }
+
+ LOG(4, s, t, " Result Code %d: %s\n", rescode, resdesc);
+ if (n >= 4)
+ {
+ uint16_t errcode = ntohs(*(uint16_t *)(b + 2));
+ errdesc = l2tp_error_code(errcode);
+ LOG(4, s, t, " Error Code %d: %s\n", errcode, errdesc);
+ }
+ if (n > 4)
+ LOG(4, s, t, " Error String: %.*s\n", n-4, b+4);
+
+ if (cause && disc_cause_set < mtype) // take cause from attrib 46 in preference
+ {
+ disc_cause_set = mtype;
+ disc_reason = errdesc ? errdesc : resdesc;
+ disc_cause = cause;
+ }
+
+ break;
+ }
+ break;
+ case 2: // protocol version
+ {
+ version = ntohs(*(uint16_t *) (b));
+ LOG(4, s, t, " Protocol version = %d\n", version);
+ if (version && version != 0x0100)
+ { // allow 0.0 and 1.0
+ LOG(1, s, t, " Bad protocol version %04X\n", version);
+ fatal = flags;
+ result = 5; // unspported protocol version
+ error = 0x0100; // supported version
+ msg = 0;
+ continue; // next
+ }
+ }
+ break;
+ case 3: // framing capabilities
+ break;
+ case 4: // bearer capabilities
+ break;
+ case 5: // tie breaker
+ // We never open tunnels, so we don't care about tie breakers
+ continue;
+ case 6: // firmware revision
+ break;
+ case 7: // host name
+ memset(tunnel[t].hostname, 0, sizeof(tunnel[t].hostname));
+ memcpy(tunnel[t].hostname, b, (n < sizeof(tunnel[t].hostname)) ? n : sizeof(tunnel[t].hostname) - 1);
+ LOG(4, s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
+ // TBA - to send to RADIUS
+ break;
+ case 8: // vendor name
+ memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
+ memcpy(tunnel[t].vendor, b, (n < sizeof(tunnel[t].vendor)) ? n : sizeof(tunnel[t].vendor) - 1);
+ LOG(4, s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
+ break;
+ case 9: // assigned tunnel
+ tunnel[t].far = ntohs(*(uint16_t *) (b));
+ LOG(4, s, t, " Remote tunnel id = %d\n", tunnel[t].far);
+ break;
+ case 10: // rx window
+ tunnel[t].window = ntohs(*(uint16_t *) (b));
+ if (!tunnel[t].window)
+ tunnel[t].window = 1; // window of 0 is silly
+ LOG(4, s, t, " rx window = %d\n", tunnel[t].window);
+ break;
+ case 11: // Challenge
+ {
+ LOG(4, s, t, " LAC requested CHAP authentication for tunnel\n");
+ build_chap_response(b, 2, n, &chapresponse);
+ }
+ break;
+ case 13: // Response
+ // Why did they send a response? We never challenge.
+ LOG(2, s, t, " received unexpected challenge response\n");
+ break;
+
+ case 14: // assigned session
+ asession = session[s].far = ntohs(*(uint16_t *) (b));
+ LOG(4, s, t, " assigned session = %d\n", asession);
+ break;
+ case 15: // call serial number
+ LOG(4, s, t, " call serial number = %d\n", ntohl(*(uint32_t *)b));
+ break;
+ case 18: // bearer type
+ LOG(4, s, t, " bearer type = %d\n", ntohl(*(uint32_t *)b));
+ // TBA - for RADIUS
+ break;
+ case 19: // framing type
+ LOG(4, s, t, " framing type = %d\n", ntohl(*(uint32_t *)b));
+ // TBA
+ break;
+ case 21: // called number
+ memset(called, 0, sizeof(called));
+ memcpy(called, b, (n < sizeof(called)) ? n : sizeof(called) - 1);
+ LOG(4, s, t, " Called <%s>\n", called);
+ break;
+ case 22: // calling number
+ memset(calling, 0, sizeof(calling));
+ memcpy(calling, b, (n < sizeof(calling)) ? n : sizeof(calling) - 1);
+ LOG(4, s, t, " Calling <%s>\n", calling);
+ break;
+ case 23: // subtype
+ break;
+ case 24: // tx connect speed
+ if (n == 4)
+ {
+ session[s].tx_connect_speed = ntohl(*(uint32_t *)b);
+ }
+ else
+ {
+ // AS5300s send connect speed as a string
+ char tmp[30];
+ memset(tmp, 0, sizeof(tmp));
+ memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
+ session[s].tx_connect_speed = atol(tmp);
+ }
+ LOG(4, s, t, " TX connect speed <%u>\n", session[s].tx_connect_speed);
+ break;
+ case 38: // rx connect speed
+ if (n == 4)
+ {
+ session[s].rx_connect_speed = ntohl(*(uint32_t *)b);
+ }
+ else
+ {
+ // AS5300s send connect speed as a string
+ char tmp[30];
+ memset(tmp, 0, sizeof(tmp));
+ memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
+ session[s].rx_connect_speed = atol(tmp);
+ }
+ LOG(4, s, t, " RX connect speed <%u>\n", session[s].rx_connect_speed);
+ break;
+ case 25: // Physical Channel ID
+ {
+ uint32_t tmp = ntohl(*(uint32_t *) b);
+ LOG(4, s, t, " Physical Channel ID <%X>\n", tmp);
+ break;
+ }
+ case 29: // Proxy Authentication Type
+ {
+ uint16_t atype = ntohs(*(uint16_t *)b);
+ LOG(4, s, t, " Proxy Auth Type %d (%s)\n", atype, ppp_auth_type(atype));
+ break;
+ }
+ case 30: // Proxy Authentication Name
+ {
+ char authname[64];
+ memset(authname, 0, sizeof(authname));
+ memcpy(authname, b, (n < sizeof(authname)) ? n : sizeof(authname) - 1);
+ LOG(4, s, t, " Proxy Auth Name (%s)\n",
+ authname);
+ break;
+ }
+ case 31: // Proxy Authentication Challenge
+ {
+ LOG(4, s, t, " Proxy Auth Challenge\n");
+ break;
+ }
+ case 32: // Proxy Authentication ID
+ {
+ uint16_t authid = ntohs(*(uint16_t *)(b));
+ LOG(4, s, t, " Proxy Auth ID (%d)\n", authid);
+ break;
+ }
+ case 33: // Proxy Authentication Response
+ LOG(4, s, t, " Proxy Auth Response\n");
+ break;
+ case 27: // last sent lcp
+ { // find magic number
+ uint8_t *p = b, *e = p + n;
+ while (p + 1 < e && p[1] && p + p[1] <= e)
+ {
+ if (*p == 5 && p[1] == 6) // Magic-Number
+ amagic = ntohl(*(uint32_t *) (p + 2));
+ else if (*p == 7) // Protocol-Field-Compression
+ aflags |= SESSION_PFC;
+ else if (*p == 8) // Address-and-Control-Field-Compression
+ aflags |= SESSION_ACFC;
+ p += p[1];
+ }
+ }
+ break;
+ case 28: // last recv lcp confreq
+ break;
+ case 26: // Initial Received LCP CONFREQ
+ break;
+ case 39: // seq required - we control it as an LNS anyway...
+ break;
+ case 36: // Random Vector
+ LOG(4, s, t, " Random Vector received. Enabled AVP Hiding.\n");
+ memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
+ if (n > sizeof(session[s].random_vector))
+ n = sizeof(session[s].random_vector);
+ memcpy(session[s].random_vector, b, n);
+ session[s].random_vector_length = n;
+ break;
+ case 46: // ppp disconnect cause
+ if (n >= 5)
+ {
+ uint16_t code = ntohs(*(uint16_t *) b);
+ uint16_t proto = ntohs(*(uint16_t *) (b + 2));
+ uint8_t dir = *(b + 4);
+
+ LOG(4, s, t, " PPP disconnect cause "
+ "(code=%u, proto=%04X, dir=%u, msg=\"%.*s\")\n",
+ code, proto, dir, n - 5, b + 5);
+
+ disc_cause_set = mtype;
+
+ switch (code)
+ {
+ case 1: // admin disconnect
+ disc_cause = TERM_ADMIN_RESET;
+ disc_reason = "Administrative disconnect";
+ break;
+ case 3: // lcp terminate
+ if (dir != 2) break; // 1=peer (LNS), 2=local (LAC)
+ disc_cause = TERM_USER_REQUEST;
+ disc_reason = "Normal disconnection";
+ break;
+ case 4: // compulsory encryption unavailable
+ if (dir != 1) break; // 1=refused by peer, 2=local
+ disc_cause = TERM_USER_ERROR;
+ disc_reason = "Compulsory encryption refused";
+ break;
+ case 5: // lcp: fsm timeout
+ disc_cause = TERM_PORT_ERROR;
+ disc_reason = "LCP: FSM timeout";
+ break;
+ case 6: // lcp: no recognisable lcp packets received
+ disc_cause = TERM_PORT_ERROR;
+ disc_reason = "LCP: no recognisable LCP packets";
+ break;
+ case 7: // lcp: magic-no error (possibly looped back)
+ disc_cause = TERM_PORT_ERROR;
+ disc_reason = "LCP: magic-no error (possible loop)";
+ break;
+ case 8: // lcp: echo request timeout
+ disc_cause = TERM_PORT_ERROR;
+ disc_reason = "LCP: echo request timeout";
+ break;
+ case 13: // auth: fsm timeout
+ disc_cause = TERM_SERVICE_UNAVAILABLE;
+ disc_reason = "Authentication: FSM timeout";
+ break;
+ case 15: // auth: unacceptable auth protocol
+ disc_cause = TERM_SERVICE_UNAVAILABLE;
+ disc_reason = "Unacceptable authentication protocol";
+ break;
+ case 16: // auth: authentication failed
+ disc_cause = TERM_SERVICE_UNAVAILABLE;
+ disc_reason = "Authentication failed";
+ break;
+ case 17: // ncp: fsm timeout
+ disc_cause = TERM_SERVICE_UNAVAILABLE;
+ disc_reason = "NCP: FSM timeout";
+ break;
+ case 18: // ncp: no ncps available
+ disc_cause = TERM_SERVICE_UNAVAILABLE;
+ disc_reason = "NCP: no NCPs available";
+ break;
+ case 19: // ncp: failure to converge on acceptable address
+ disc_cause = TERM_SERVICE_UNAVAILABLE;
+ disc_reason = (dir == 1)
+ ? "NCP: too many Configure-Naks received from peer"
+ : "NCP: too many Configure-Naks sent to peer";
+ break;
+ case 20: // ncp: user not permitted to use any address
+ disc_cause = TERM_SERVICE_UNAVAILABLE;
+ disc_reason = (dir == 1)
+ ? "NCP: local link address not acceptable to peer"
+ : "NCP: remote link address not acceptable";
+ break;
+ }
+ }
+ break;
+ default:
+ {
+ static char e[] = "unknown AVP 0xXXXX";
+ LOG(2, s, t, " Unknown AVP type %d\n", mtype);
+ fatal = flags;
+ result = 2; // general error
+ error = 8; // unknown mandatory AVP
+ sprintf((msg = e) + 14, "%04x", mtype);
+ continue; // next
+ }
+ }
+ }
+ // process message
+ if (fatal & 0x80)
+ tunnelshutdown(t, "Invalid mandatory AVP", result, error, msg);
+ else
+ switch (message)
+ {
+ case 1: // SCCRQ - Start Control Connection Request
+ tunnel[t].state = TUNNELOPENING;
+ if (main_quit != QUIT_SHUTDOWN)
+ {
+ controlt *c = controlnew(2); // sending SCCRP
+ control16(c, 2, version, 1); // protocol version
+ control32(c, 3, 3, 1); // framing
+ controls(c, 7, hostname, 1); // host name
+ if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
+ control16(c, 9, t, 1); // assigned tunnel
+ controladd(c, 0, t); // send the resply
+ }
+ else
+ {
+ tunnelshutdown(t, "Shutting down", 6, 0, 0);
+ }
+ break;
+ case 2: // SCCRP
+ tunnel[t].state = TUNNELOPEN;
+ break;
+ case 3: // SCCN
+ tunnel[t].state = TUNNELOPEN;
+ controlnull(t); // ack
+ break;
+ case 4: // StopCCN
+ controlnull(t); // ack
+ tunnelshutdown(t, "Stopped", 0, 0, 0); // Shut down cleanly
+ break;
+ case 6: // HELLO
+ controlnull(t); // simply ACK
+ break;
+ case 7: // OCRQ
+ // TBA
+ break;
+ case 8: // OCRO
+ // TBA
+ break;
+ case 9: // OCCN
+ // TBA
+ break;
+ case 10: // ICRQ
+ if (sessionfree && main_quit != QUIT_SHUTDOWN)
+ {
+ controlt *c = controlnew(11); // ICRP
+
+ s = sessionfree;
+ sessionfree = session[s].next;
+ memset(&session[s], 0, sizeof(session[s]));
+
+ if (s > config->cluster_highest_sessionid)
+ config->cluster_highest_sessionid = s;
+
+ session[s].opened = time_now;
+ session[s].tunnel = t;
+ session[s].far = asession;
+ session[s].last_packet = time_now;
+ LOG(3, s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
+ control16(c, 14, s, 1); // assigned session
+ controladd(c, asession, t); // send the reply
+
+ strncpy(session[s].called, called, sizeof(session[s].called) - 1);
+ strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
+
+ session[s].ppp.phase = Establish;
+ session[s].ppp.lcp = Starting;
+
+ STAT(session_created);
+ break;
+ }
+
+ {
+ controlt *c = controlnew(14); // CDN
+ if (!sessionfree)
+ {
+ STAT(session_overflow);
+ LOG(1, 0, t, "No free sessions\n");
+ control16(c, 1, 4, 0); // temporary lack of resources
+ }
+ else
+ control16(c, 1, 2, 7); // shutting down, try another
+
+ controladd(c, asession, t); // send the message
+ }
+ return;
+ case 11: // ICRP
+ // TBA
+ break;
+ case 12: // ICCN
+ if (amagic == 0) amagic = time_now;
+ session[s].magic = amagic; // set magic number
+ session[s].flags = aflags; // set flags received
+ session[s].mru = PPPoE_MRU; // default
+ controlnull(t); // ack
+
+ // start LCP
+ sess_local[s].lcp_authtype = config->radius_authprefer;
+ sess_local[s].ppp_mru = MRU;
+ sendlcp(s, t);
+ change_state(s, lcp, RequestSent);
+ break;
+
+ case 14: // CDN
+ controlnull(t); // ack
+ sessionshutdown(s, disc_reason, CDN_NONE, disc_cause);
+ break;
+ case 0xFFFF:
+ LOG(1, s, t, "Missing message type\n");
+ break;
+ default:
+ STAT(tunnel_rx_errors);
+ if (mandatory)
+ tunnelshutdown(t, "Unknown message type", 2, 6, "unknown message type");
+ else
+ LOG(1, s, t, "Unknown message type %d\n", message);
+ break;
+ }
+ if (chapresponse) free(chapresponse);
+ cluster_send_tunnel(t);
+ }
+ else
+ {
+ LOG(4, s, t, " Got a ZLB ack\n");
+ }
+ }
+ else
+ { // data
+ uint16_t proto;
+
+ LOG_HEX(5, "Receive Tunnel Data", p, l);
+ if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
+ { // HDLC address header, discard
+ p += 2;
+ l -= 2;
+ }
+ if (l < 2)
+ {
+ LOG(1, s, t, "Short ppp length %d\n", l);
+ STAT(tunnel_rx_errors);
+ return;
+ }
+ if (*p & 1)
+ {
+ proto = *p++;
+ l--;
+ }
+ else
+ {
+ proto = ntohs(*(uint16_t *) p);
+ p += 2;
+ l -= 2;
+ }
+
+ if (s && !session[s].opened) // Is something wrong??
+ {
+ if (!config->cluster_iam_master)
+ {
+ // Pass it off to the master to deal with..
+ master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
+ return;
+ }
+
+
+ LOG(1, s, t, "UDP packet contains session which is not opened. Dropping packet.\n");
+ STAT(tunnel_rx_errors);
+ return;
+ }
+
+ if (proto == PPPPAP)
+ {
+ session[s].last_packet = time_now;
+ if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
+ processpap(s, t, p, l);
+ }
+ else if (proto == PPPCHAP)
+ {
+ session[s].last_packet = time_now;
+ if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
+ processchap(s, t, p, l);
+ }
+ else if (proto == PPPLCP)
+ {
+ session[s].last_packet = time_now;
+ if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
+ processlcp(s, t, p, l);
+ }
+ else if (proto == PPPIPCP)
+ {
+ session[s].last_packet = time_now;
+ if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
+ processipcp(s, t, p, l);
+ }
+ else if (proto == PPPIPV6CP && config->ipv6_prefix.s6_addr[0])
+ {
+ session[s].last_packet = time_now;
+ if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
+ processipv6cp(s, t, p, l);
+ }
+ else if (proto == PPPCCP)
+ {
+ session[s].last_packet = time_now;
+ if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
+ processccp(s, t, p, l);
+ }
+ else if (proto == PPPIP)
+ {
+ if (session[s].die)
+ {
+ LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
+ return; // closing session, PPP not processed
+ }
+
+ session[s].last_packet = time_now;
+ if (session[s].walled_garden && !config->cluster_iam_master)
+ {
+ master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
+ return;
+ }
+
+ processipin(s, t, p, l);
+ }
+ else if (proto == PPPIPV6 && config->ipv6_prefix.s6_addr[0])
+ {
+ if (session[s].die)
+ {
+ LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
+ return; // closing session, PPP not processed
+ }
+
+ session[s].last_packet = time_now;
+ if (session[s].walled_garden && !config->cluster_iam_master)
+ {
+ master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
+ return;
+ }
+
+ processipv6in(s, t, p, l);
+ }
+ else if (session[s].ppp.lcp == Opened)
+ {
+ session[s].last_packet = time_now;
+ if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
+ protoreject(s, t, p, l, proto);
+ }
+ else
+ {
+ LOG(2, s, t, "Unknown PPP protocol 0x%04X received in LCP %s state\n",
+ proto, ppp_state(session[s].ppp.lcp));
+ }
+ }
+}
+
+// read and process packet on tun
+static void processtun(uint8_t * buf, int len)
+{
+ LOG_HEX(5, "Receive TUN Data", buf, len);
+ STAT(tun_rx_packets);
+ INC_STAT(tun_rx_bytes, len);
+
+ CSTAT(processtun);
+
+ eth_rx_pkt++;
+ eth_rx += len;
+ if (len < 22)
+ {
+ LOG(1, 0, 0, "Short tun packet %d bytes\n", len);
+ STAT(tun_rx_errors);
+ return;
+ }
+
+ if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IPv4
+ processipout(buf, len);
+ else if (*(uint16_t *) (buf + 2) == htons(PKTIPV6) // IPV6
+ && config->ipv6_prefix.s6_addr[0])
+ processipv6out(buf, len);
+
+ // Else discard.
+}
+
+// Handle retries, timeouts. Runs every 1/10th sec, want to ensure
+// that we look at the whole of the tunnel, radius and session tables
+// every second
+static void regular_cleanups(double period)
+{
+ // Next tunnel, radius and session to check for actions on.
+ static tunnelidt t = 0;
+ static int r = 0;
+ static sessionidt s = 0;
+
+ int t_actions = 0;
+ int r_actions = 0;
+ int s_actions = 0;
+
+ int t_slice;
+ int r_slice;
+ int s_slice;
+
+ int i;
+ int a;
+
+ // divide up tables into slices based on the last run
+ t_slice = config->cluster_highest_tunnelid * period;
+ r_slice = (MAXRADIUS - 1) * period;
+ s_slice = config->cluster_highest_sessionid * period;
+
+ if (t_slice < 1)
+ t_slice = 1;
+ else if (t_slice > config->cluster_highest_tunnelid)
+ t_slice = config->cluster_highest_tunnelid;
+
+ if (r_slice < 1)
+ r_slice = 1;
+ else if (r_slice > (MAXRADIUS - 1))
+ r_slice = MAXRADIUS - 1;
+
+ if (s_slice < 1)
+ s_slice = 1;
+ else if (s_slice > config->cluster_highest_sessionid)
+ s_slice = config->cluster_highest_sessionid;
+
+ LOG(4, 0, 0, "Begin regular cleanup (last %f seconds ago)\n", period);
+
+ for (i = 0; i < t_slice; i++)
+ {
+ t++;
+ if (t > config->cluster_highest_tunnelid)
+ t = 1;
+
+ // check for expired tunnels
+ if (tunnel[t].die && tunnel[t].die <= TIME)
+ {
+ STAT(tunnel_timeout);
+ tunnelkill(t, "Expired");
+ t_actions++;
+ continue;
+ }
+ // check for message resend
+ if (tunnel[t].retry && tunnel[t].controlc)
+ {
+ // resend pending messages as timeout on reply
+ if (tunnel[t].retry <= TIME)
+ {
+ controlt *c = tunnel[t].controls;
+ uint8_t w = tunnel[t].window;
+ tunnel[t].try++; // another try
+ if (tunnel[t].try > 5)
+ tunnelkill(t, "Timeout on control message"); // game over
+ else
+ while (c && w--)
+ {
+ tunnelsend(c->buf, c->length, t);
+ c = c->next;
+ }
+
+ t_actions++;
+ }
+ }
+ // Send hello
+ if (tunnel[t].state == TUNNELOPEN && !tunnel[t].controlc && (time_now - tunnel[t].lastrec) > 60)
+ {
+ controlt *c = controlnew(6); // sending HELLO
+ controladd(c, 0, t); // send the message
+ LOG(3, 0, t, "Sending HELLO message\n");
+ t_actions++;
+ }
+
+ // Check for tunnel changes requested from the CLI
+ if ((a = cli_tunnel_actions[t].action))
+ {
+ cli_tunnel_actions[t].action = 0;
+ if (a & CLI_TUN_KILL)
+ {
+ LOG(2, 0, t, "Dropping tunnel by CLI\n");
+ tunnelshutdown(t, "Requested by administrator", 1, 0, 0);
+ t_actions++;
+ }
+ }
+ }
+
+ for (i = 0; i < r_slice; i++)
+ {
+ r++;
+ if (r >= MAXRADIUS)
+ r = 1;
+
+ if (!radius[r].state)
+ continue;
+
+ if (radius[r].retry <= TIME)
+ {
+ radiusretry(r);
+ r_actions++;
+ }
+ }
+
+ for (i = 0; i < s_slice; i++)
+ {
+ s++;
+ if (s > config->cluster_highest_sessionid)
+ s = 1;
+
+ if (!session[s].opened) // Session isn't in use
+ continue;
+
+ // check for expired sessions
+ if (session[s].die)
+ {
+ if (session[s].die <= TIME)
+ {
+ sessionkill(s, "Expired");
+ s_actions++;
+ }
+ continue;
+ }
+
+ // PPP timeouts
+ if (sess_local[s].lcp.restart <= time_now)
+ {
+ int next_state = session[s].ppp.lcp;
+ switch (session[s].ppp.lcp)
+ {
+ case RequestSent:
+ case AckReceived:
+ next_state = RequestSent;
+
+ case AckSent:
+ if (sess_local[s].lcp.conf_sent < config->ppp_max_configure)
+ {
+ LOG(3, s, session[s].tunnel, "No ACK for LCP ConfigReq... resending\n");
+ sendlcp(s, session[s].tunnel);
+ change_state(s, lcp, next_state);
+ }
+ else
+ {
+ sessionshutdown(s, "No response to LCP ConfigReq.", CDN_ADMIN_DISC, TERM_LOST_SERVICE);
+ STAT(session_timeout);
+ }
+
+ s_actions++;
+ }
+
+ if (session[s].die)
+ continue;
+ }
+
+ if (sess_local[s].ipcp.restart <= time_now)
+ {
+ int next_state = session[s].ppp.ipcp;
+ switch (session[s].ppp.ipcp)
+ {
+ case RequestSent:
+ case AckReceived:
+ next_state = RequestSent;
+
+ case AckSent:
+ if (sess_local[s].ipcp.conf_sent < config->ppp_max_configure)
+ {
+ LOG(3, s, session[s].tunnel, "No ACK for IPCP ConfigReq... resending\n");
+ sendipcp(s, session[s].tunnel);
+ change_state(s, ipcp, next_state);
+ }
+ else
+ {
+ sessionshutdown(s, "No response to IPCP ConfigReq.", CDN_ADMIN_DISC, TERM_LOST_SERVICE);
+ STAT(session_timeout);
+ }
+
+ s_actions++;
+ }
+
+ if (session[s].die)
+ continue;
+ }
+
+ if (sess_local[s].ipv6cp.restart <= time_now)
+ {
+ int next_state = session[s].ppp.ipv6cp;
+ switch (session[s].ppp.ipv6cp)
+ {
+ case RequestSent:
+ case AckReceived:
+ next_state = RequestSent;
+
+ case AckSent:
+ if (sess_local[s].ipv6cp.conf_sent < config->ppp_max_configure)
+ {
+ LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq... resending\n");
+ sendipv6cp(s, session[s].tunnel);
+ change_state(s, ipv6cp, next_state);
+ }
+ else
+ {
+ LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq\n");
+ change_state(s, ipv6cp, Stopped);
+ }
+
+ s_actions++;
+ }
+ }
+
+ if (sess_local[s].ccp.restart <= time_now)
+ {
+ int next_state = session[s].ppp.ccp;
+ switch (session[s].ppp.ccp)
+ {
+ case RequestSent:
+ case AckReceived:
+ next_state = RequestSent;
+
+ case AckSent:
+ if (sess_local[s].ccp.conf_sent < config->ppp_max_configure)
+ {
+ LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq... resending\n");
+ sendccp(s, session[s].tunnel);
+ change_state(s, ccp, next_state);
+ }
+ else
+ {
+ LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq\n");
+ change_state(s, ccp, Stopped);
+ }
+
+ s_actions++;
+ }
+ }
+
+ // Drop sessions who have not responded within IDLE_TIMEOUT seconds
+ if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
+ {
+ sessionshutdown(s, "No response to LCP ECHO requests.", CDN_ADMIN_DISC, TERM_LOST_SERVICE);
+ STAT(session_timeout);
+ s_actions++;
+ continue;
+ }
+
+ // No data in ECHO_TIMEOUT seconds, send LCP ECHO
+ if (session[s].ppp.phase >= Establish && (time_now - session[s].last_packet >= ECHO_TIMEOUT) &&
+ (time_now - sess_local[s].last_echo >= ECHO_TIMEOUT))
+ {
+ uint8_t b[MAXETHER];
+
+ uint8_t *q = makeppp(b, sizeof(b), 0, 0, s, session[s].tunnel, PPPLCP);
+ if (!q) continue;
+
+ *q = EchoReq;
+ *(uint8_t *)(q + 1) = (time_now % 255); // ID
+ *(uint16_t *)(q + 2) = htons(8); // Length
+ *(uint32_t *)(q + 4) = session[s].ppp.lcp == Opened ? htonl(session[s].magic) : 0; // Magic Number
+
+ LOG(4, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
+ (int)(time_now - session[s].last_packet));
+ tunnelsend(b, 24, session[s].tunnel); // send it
+ sess_local[s].last_echo = time_now;
+ s_actions++;
+ }
+
+ // Check for actions requested from the CLI
+ if ((a = cli_session_actions[s].action))
+ {
+ int send = 0;
+
+ cli_session_actions[s].action = 0;
+ if (a & CLI_SESS_KILL)
+ {
+ LOG(2, s, session[s].tunnel, "Dropping session by CLI\n");
+ sessionshutdown(s, "Requested by administrator.", CDN_ADMIN_DISC, TERM_ADMIN_RESET);
+ a = 0; // dead, no need to check for other actions
+ s_actions++;
+ }
+
+ if (a & CLI_SESS_NOSNOOP)
+ {
+ LOG(2, s, session[s].tunnel, "Unsnooping session by CLI\n");
+ session[s].snoop_ip = 0;
+ session[s].snoop_port = 0;
+ s_actions++;
+ send++;
+ }
+ else if (a & CLI_SESS_SNOOP)
+ {
+ LOG(2, s, session[s].tunnel, "Snooping session by CLI (to %s:%d)\n",
+ fmtaddr(cli_session_actions[s].snoop_ip, 0),
+ cli_session_actions[s].snoop_port);
+
+ session[s].snoop_ip = cli_session_actions[s].snoop_ip;
+ session[s].snoop_port = cli_session_actions[s].snoop_port;
+ s_actions++;
+ send++;
+ }
+
+ if (a & CLI_SESS_NOTHROTTLE)
+ {
+ LOG(2, s, session[s].tunnel, "Un-throttling session by CLI\n");
+ throttle_session(s, 0, 0);
+ s_actions++;
+ send++;
+ }
+ else if (a & CLI_SESS_THROTTLE)
+ {
+ LOG(2, s, session[s].tunnel, "Throttling session by CLI (to %dkb/s up and %dkb/s down)\n",
+ cli_session_actions[s].throttle_in,
+ cli_session_actions[s].throttle_out);
+
+ throttle_session(s, cli_session_actions[s].throttle_in, cli_session_actions[s].throttle_out);
+ s_actions++;
+ send++;
+ }
+
+ if (a & CLI_SESS_NOFILTER)
+ {
+ LOG(2, s, session[s].tunnel, "Un-filtering session by CLI\n");
+ filter_session(s, 0, 0);
+ s_actions++;
+ send++;
+ }
+ else if (a & CLI_SESS_FILTER)
+ {
+ LOG(2, s, session[s].tunnel, "Filtering session by CLI (in=%d, out=%d)\n",
+ cli_session_actions[s].filter_in,
+ cli_session_actions[s].filter_out);
+
+ filter_session(s, cli_session_actions[s].filter_in, cli_session_actions[s].filter_out);
+ s_actions++;
+ send++;
+ }
+
+ if (send)
+ cluster_send_session(s);
+ }
+
+ // RADIUS interim accounting
+ if (config->radius_accounting && config->radius_interim > 0
+ && session[s].ip && !session[s].walled_garden
+ && !sess_local[s].radius // RADIUS already in progress
+ && time_now - sess_local[s].last_interim >= config->radius_interim)
+ {
+ int rad = radiusnew(s);
+ if (!rad)
+ {
+ LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Interim message\n");
+ STAT(radius_overflow);
+ continue;
+ }
+
+ LOG(3, s, session[s].tunnel, "Sending RADIUS Interim for %s (%u)\n",
+ session[s].user, session[s].unique_id);
+
+ radiussend(rad, RADIUSINTERIM);
+ sess_local[s].last_interim = time_now;
+ s_actions++;
+ }
+ }
+
+ LOG(4, 0, 0, "End regular cleanup: checked %d/%d/%d tunnels/radius/sessions; %d/%d/%d actions\n",
+ t_slice, r_slice, s_slice, t_actions, r_actions, s_actions);
+}
+
+//
+// Are we in the middle of a tunnel update, or radius
+// requests??
+//
+static int still_busy(void)
+{
+ int i;
+ static clockt last_talked = 0;
+ static clockt start_busy_wait = 0;
+
+ if (!config->cluster_iam_master)
+ {
+#ifdef BGP
+ static time_t stopped_bgp = 0;
+ if (bgp_configured)
+ {
+ if (!stopped_bgp)
+ {
+ LOG(1, 0, 0, "Shutting down in %d seconds, stopping BGP...\n", QUIT_DELAY);
+
+ for (i = 0; i < BGP_NUM_PEERS; i++)
+ if (bgp_peers[i].state == Established)
+ bgp_stop(&bgp_peers[i]);
+
+ stopped_bgp = time_now;
+
+ // we don't want to become master
+ cluster_send_ping(0);
+
+ return 1;
+ }
+
+ if (time_now < (stopped_bgp + QUIT_DELAY))
+ return 1;
+ }
+#endif /* BGP */
+
+ return 0;
+ }
+
+ if (main_quit == QUIT_SHUTDOWN)
+ {
+ static int dropped = 0;
+ if (!dropped)
+ {
+ int i;
+
+ LOG(1, 0, 0, "Dropping sessions and tunnels\n");
+ for (i = 1; i < MAXTUNNEL; i++)
+ if (tunnel[i].ip || tunnel[i].state)
+ tunnelshutdown(i, "L2TPNS Closing", 6, 0, 0);
+
+ dropped = 1;
+ }
+ }
+
+ if (start_busy_wait == 0)
+ start_busy_wait = TIME;
+
+ for (i = config->cluster_highest_tunnelid ; i > 0 ; --i)
+ {
+ if (!tunnel[i].controlc)
+ continue;
+
+ if (last_talked != TIME)
+ {
+ LOG(2, 0, 0, "Tunnel %d still has un-acked control messages.\n", i);
+ last_talked = TIME;
+ }
+ return 1;
+ }
+
+ // We stop waiting for radius after BUSY_WAIT_TIME 1/10th seconds
+ if (abs(TIME - start_busy_wait) > BUSY_WAIT_TIME)
+ {
+ LOG(1, 0, 0, "Giving up waiting for RADIUS to be empty. Shutting down anyway.\n");
+ return 0;
+ }
+
+ for (i = 1; i < MAXRADIUS; i++)
+ {
+ if (radius[i].state == RADIUSNULL)
+ continue;
+ if (radius[i].state == RADIUSWAIT)
+ continue;
+
+ if (last_talked != TIME)
+ {
+ LOG(2, 0, 0, "Radius session %d is still busy (sid %d)\n", i, radius[i].session);
+ last_talked = TIME;
+ }
+ return 1;
+ }
+
+ return 0;
+}
+
+#ifdef HAVE_EPOLL
+# include <sys/epoll.h>
+#else
+# define FAKE_EPOLL_IMPLEMENTATION /* include the functions */
+# include "fake_epoll.h"
+#endif
+
+// the base set of fds polled: cli, cluster, tun, udp, control, dae
+#define BASE_FDS 6
+
+// additional polled fds
+#ifdef BGP
+# define EXTRA_FDS BGP_NUM_PEERS
+#else
+# define EXTRA_FDS 0
+#endif
+
+// main loop - gets packets on tun or udp and processes them
+static void mainloop(void)
+{
+ int i;
+ uint8_t buf[65536];
+ clockt next_cluster_ping = 0; // send initial ping immediately
+ struct epoll_event events[BASE_FDS + RADIUS_FDS + EXTRA_FDS];
+ int maxevent = sizeof(events)/sizeof(*events);
+
+ if ((epollfd = epoll_create(maxevent)) < 0)
+ {
+ LOG(0, 0, 0, "epoll_create failed: %s\n", strerror(errno));
+ exit(1);
+ }
+
+ LOG(4, 0, 0, "Beginning of main loop. clifd=%d, cluster_sockfd=%d, tunfd=%d, udpfd=%d, controlfd=%d, daefd=%d\n",
+ clifd, cluster_sockfd, tunfd, udpfd, controlfd, daefd);
+
+ /* setup our fds to poll for input */
+ {
+ static struct event_data d[BASE_FDS];
+ struct epoll_event e;
+
+ e.events = EPOLLIN;
+ i = 0;
+
+ d[i].type = FD_TYPE_CLI;
+ e.data.ptr = &d[i++];
+ epoll_ctl(epollfd, EPOLL_CTL_ADD, clifd, &e);
+
+ d[i].type = FD_TYPE_CLUSTER;
+ e.data.ptr = &d[i++];
+ epoll_ctl(epollfd, EPOLL_CTL_ADD, cluster_sockfd, &e);
+
+ d[i].type = FD_TYPE_TUN;
+ e.data.ptr = &d[i++];
+ epoll_ctl(epollfd, EPOLL_CTL_ADD, tunfd, &e);
+
+ d[i].type = FD_TYPE_UDP;
+ e.data.ptr = &d[i++];
+ epoll_ctl(epollfd, EPOLL_CTL_ADD, udpfd, &e);
+
+ d[i].type = FD_TYPE_CONTROL;
+ e.data.ptr = &d[i++];
+ epoll_ctl(epollfd, EPOLL_CTL_ADD, controlfd, &e);
+
+ d[i].type = FD_TYPE_DAE;
+ e.data.ptr = &d[i++];
+ epoll_ctl(epollfd, EPOLL_CTL_ADD, daefd, &e);
+ }
+
+#ifdef BGP
+ signal(SIGPIPE, SIG_IGN);
+ bgp_setup(config->as_number);
+ if (config->bind_address)
+ bgp_add_route(config->bind_address, 0xffffffff);
+
+ for (i = 0; i < BGP_NUM_PEERS; i++)
+ {
+ if (config->neighbour[i].name[0])
+ bgp_start(&bgp_peers[i], config->neighbour[i].name,
+ config->neighbour[i].as, config->neighbour[i].keepalive,
+ config->neighbour[i].hold, 0); /* 0 = routing disabled */
+ }
+#endif /* BGP */
+
+ while (!main_quit || still_busy())
+ {
+ int more = 0;
+ int n;
+
+
+ if (main_reload)
+ {
+ main_reload = 0;
+ read_config_file();
+ config->reload_config++;
+ }
+
+ if (config->reload_config)
+ {
+ config->reload_config = 0;
+ update_config();
+ }
+
+#ifdef BGP
+ bgp_set_poll();
+#endif /* BGP */
+
+ n = epoll_wait(epollfd, events, maxevent, 100); // timeout 100ms (1/10th sec)
+ STAT(select_called);
+
+ TIME = now(NULL);
+ if (n < 0)
+ {
+ if (errno == EINTR ||
+ errno == ECHILD) // EINTR was clobbered by sigchild_handler()
+ continue;
+
+ LOG(0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
+ break; // exit
+ }
+
+ if (n)
+ {
+ struct sockaddr_in addr;
+ struct in_addr local;
+ socklen_t alen;
+ int c, s;
+ int udp_ready = 0;
+ int tun_ready = 0;
+ int cluster_ready = 0;
+ int udp_pkts = 0;
+ int tun_pkts = 0;
+ int cluster_pkts = 0;
+#ifdef BGP
+ uint32_t bgp_events[BGP_NUM_PEERS];
+ memset(bgp_events, 0, sizeof(bgp_events));
+#endif /* BGP */
+
+ for (c = n, i = 0; i < c; i++)
+ {
+ struct event_data *d = events[i].data.ptr;
+
+ switch (d->type)
+ {
+ case FD_TYPE_CLI: // CLI connections
+ {
+ int cli;
+
+ alen = sizeof(addr);
+ if ((cli = accept(clifd, (struct sockaddr *)&addr, &alen)) >= 0)
+ {
+ cli_do(cli);
+ close(cli);
+ }
+ else
+ LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
+
+ n--;
+ break;
+ }
+
+ // these are handled below, with multiple interleaved reads
+ case FD_TYPE_CLUSTER: cluster_ready++; break;
+ case FD_TYPE_TUN: tun_ready++; break;
+ case FD_TYPE_UDP: udp_ready++; break;
+
+ case FD_TYPE_CONTROL: // nsctl commands
+ alen = sizeof(addr);
+ s = recvfromto(controlfd, buf, sizeof(buf), MSG_WAITALL, (struct sockaddr *) &addr, &alen, &local);
+ if (s > 0) processcontrol(buf, s, &addr, alen, &local);
+ n--;
+ break;
+
+ case FD_TYPE_DAE: // DAE requests
+ alen = sizeof(addr);
+ s = recvfromto(daefd, buf, sizeof(buf), MSG_WAITALL, (struct sockaddr *) &addr, &alen, &local);
+ if (s > 0) processdae(buf, s, &addr, alen, &local);
+ n--;
+ break;
+
+ case FD_TYPE_RADIUS: // RADIUS response
+ alen = sizeof(addr);
+ s = recvfrom(radfds[d->index], buf, sizeof(buf), MSG_WAITALL, (struct sockaddr *) &addr, &alen);
+ if (s >= 0 && config->cluster_iam_master)
+ {
+ if (addr.sin_addr.s_addr == config->radiusserver[0] ||
+ addr.sin_addr.s_addr == config->radiusserver[1])
+ processrad(buf, s, d->index);
+ else
+ LOG(3, 0, 0, "Dropping RADIUS packet from unknown source %s\n",
+ fmtaddr(addr.sin_addr.s_addr, 0));
+ }
+
+ n--;
+ break;
+
+#ifdef BGP
+ case FD_TYPE_BGP:
+ bgp_events[d->index] = events[i].events;
+ n--;
+ break;
+#endif /* BGP */
+
+ default:
+ LOG(0, 0, 0, "Unexpected fd type returned from epoll_wait: %d\n", d->type);
+ }
+ }
+
+#ifdef BGP
+ bgp_process(bgp_events);
+#endif /* BGP */
+
+ for (c = 0; n && c < config->multi_read_count; c++)
+ {
+ // L2TP
+ if (udp_ready)
+ {
+ alen = sizeof(addr);
+ if ((s = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
+ {
+ processudp(buf, s, &addr);
+ udp_pkts++;
+ }
+ else
+ {
+ udp_ready = 0;
+ n--;
+ }
+ }
+
+ // incoming IP
+ if (tun_ready)
+ {
+ if ((s = read(tunfd, buf, sizeof(buf))) > 0)
+ {
+ processtun(buf, s);
+ tun_pkts++;
+ }
+ else
+ {
+ tun_ready = 0;
+ n--;
+ }
+ }
+
+ // cluster
+ if (cluster_ready)
+ {
+ alen = sizeof(addr);
+ if ((s = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen)) > 0)
+ {
+ processcluster(buf, s, addr.sin_addr.s_addr);
+ cluster_pkts++;
+ }
+ else
+ {
+ cluster_ready = 0;
+ n--;
+ }
+ }
+ }
+
+ if (udp_pkts > 1 || tun_pkts > 1 || cluster_pkts > 1)
+ STAT(multi_read_used);
+
+ if (c >= config->multi_read_count)
+ {
+ LOG(3, 0, 0, "Reached multi_read_count (%d); processed %d udp, %d tun and %d cluster packets\n",
+ config->multi_read_count, udp_pkts, tun_pkts, cluster_pkts);
+
+ STAT(multi_read_exceeded);
+ more++;
+ }
+ }
+
+ if (time_changed)
+ {
+ double Mbps = 1024.0 * 1024.0 / 8 * time_changed;
+
+ // Log current traffic stats
+ snprintf(config->bandwidth, sizeof(config->bandwidth),
+ "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
+ (udp_rx / Mbps), (eth_tx / Mbps), (eth_rx / Mbps), (udp_tx / Mbps),
+ ((udp_tx + udp_rx + eth_tx + eth_rx) / Mbps),
+ udp_rx_pkt / time_changed, eth_rx_pkt / time_changed);
+
+ udp_tx = udp_rx = 0;
+ udp_rx_pkt = eth_rx_pkt = 0;
+ eth_tx = eth_rx = 0;
+ time_changed = 0;
+
+ if (config->dump_speed)
+ printf("%s\n", config->bandwidth);
+
+ // Update the internal time counter
+ strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
+
+ {
+ // Run timer hooks
+ struct param_timer p = { time_now };
+ run_plugins(PLUGIN_TIMER, &p);
+ }
+ }
+
+ // Runs on every machine (master and slaves).
+ if (next_cluster_ping <= TIME)
+ {
+ // Check to see which of the cluster is still alive..
+
+ cluster_send_ping(basetime); // Only does anything if we're a slave
+ cluster_check_master(); // ditto.
+
+ cluster_heartbeat(); // Only does anything if we're a master.
+ cluster_check_slaves(); // ditto.
+
+ master_update_counts(); // If we're a slave, send our byte counters to our master.
+
+ if (config->cluster_iam_master && !config->cluster_iam_uptodate)
+ next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
+ else
+ next_cluster_ping = TIME + config->cluster_hb_interval;
+ }
+
+ if (!config->cluster_iam_master)
+ continue;
+
+ // Run token bucket filtering queue..
+ // Only run it every 1/10th of a second.
+ {
+ static clockt last_run = 0;
+ if (last_run != TIME)
+ {
+ last_run = TIME;
+ tbf_run_timer();
+ }
+ }
+
+ // Handle timeouts, retries etc.
+ {
+ static double last_clean = 0;
+ double this_clean;
+ double diff;
+
+ TIME = now(&this_clean);
+ diff = this_clean - last_clean;
+
+ // Run during idle time (after we've handled
+ // all incoming packets) or every 1/10th sec
+ if (!more || diff > 0.1)
+ {
+ regular_cleanups(diff);
+ last_clean = this_clean;
+ }
+ }
+
+ if (*config->accounting_dir)
+ {
+ static clockt next_acct = 0;
+ static clockt next_shut_acct = 0;
+
+ if (next_acct <= TIME)
+ {
+ // Dump accounting data
+ next_acct = TIME + ACCT_TIME;
+ next_shut_acct = TIME + ACCT_SHUT_TIME;
+ dump_acct_info(1);
+ }
+ else if (next_shut_acct <= TIME)
+ {
+ // Dump accounting data for shutdown sessions
+ next_shut_acct = TIME + ACCT_SHUT_TIME;
+ if (shut_acct_n)
+ dump_acct_info(0);
+ }
+ }
+ }
+
+ // Are we the master and shutting down??
+ if (config->cluster_iam_master)
+ cluster_heartbeat(); // Flush any queued changes..
+
+ // Ok. Notify everyone we're shutting down. If we're
+ // the master, this will force an election.
+ cluster_send_ping(0);
+
+ //
+ // Important!!! We MUST not process any packets past this point!
+ LOG(1, 0, 0, "Shutdown complete\n");
+}
+
+static void stripdomain(char *host)
+{
+ char *p;
+
+ if ((p = strchr(host, '.')))
+ {
+ char *domain = 0;
+ char _domain[1024];
+
+ // strip off domain
+ FILE *resolv = fopen("/etc/resolv.conf", "r");
+ if (resolv)
+ {
+ char buf[1024];
+ char *b;
+
+ while (fgets(buf, sizeof(buf), resolv))
+ {
+ if (strncmp(buf, "domain", 6) && strncmp(buf, "search", 6))
+ continue;
+
+ if (!isspace(buf[6]))
+ continue;
+
+ b = buf + 7;
+ while (isspace(*b)) b++;
+
+ if (*b)
+ {
+ char *d = b;
+ while (*b && !isspace(*b)) b++;
+ *b = 0;
+ if (buf[0] == 'd') // domain is canonical
+ {
+ domain = d;
+ break;
+ }
+
+ // first search line
+ if (!domain)
+ {
+ // hold, may be subsequent domain line
+ strncpy(_domain, d, sizeof(_domain))[sizeof(_domain)-1] = 0;
+ domain = _domain;
+ }
+ }
+ }
+
+ fclose(resolv);
+ }
+
+ if (domain)
+ {
+ int hl = strlen(host);
+ int dl = strlen(domain);
+ if (dl < hl && host[hl - dl - 1] == '.' && !strcmp(host + hl - dl, domain))
+ host[hl -dl - 1] = 0;
+ }
+ else
+ {
+ *p = 0; // everything after first dot
+ }
+ }
+}
+
+// Init data structures
+static void initdata(int optdebug, char *optconfig)
+{
+ int i;
+
+ if (!(config = shared_malloc(sizeof(configt))))
+ {
+ fprintf(stderr, "Error doing malloc for configuration: %s\n", strerror(errno));
+ exit(1);
+ }
+
+ memset(config, 0, sizeof(configt));
+ time(&config->start_time);
+ strncpy(config->config_file, optconfig, strlen(optconfig));
+ config->debug = optdebug;
+ config->num_tbfs = MAXTBFS;
+ config->rl_rate = 28; // 28kbps
+ config->cluster_mcast_ttl = 1;
+ config->cluster_master_min_adv = 1;
+ config->ppp_restart_time = 3;
+ config->ppp_max_configure = 10;
+ config->ppp_max_failure = 5;
+ strcpy(config->random_device, RANDOMDEVICE);
+
+ log_stream = stderr;
+
+#ifdef RINGBUFFER
+ if (!(ringbuffer = shared_malloc(sizeof(struct Tringbuffer))))
+ {
+ LOG(0, 0, 0, "Error doing malloc for ringbuffer: %s\n", strerror(errno));
+ exit(1);
+ }
+ memset(ringbuffer, 0, sizeof(struct Tringbuffer));
+#endif
+
+ if (!(_statistics = shared_malloc(sizeof(struct Tstats))))
+ {
+ LOG(0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno));
+ exit(1);
+ }
+ if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)))
+ {
+ LOG(0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno));
+ exit(1);
+ }
+ if (!(session = shared_malloc(sizeof(sessiont) * MAXSESSION)))
+ {
+ LOG(0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno));
+ exit(1);
+ }
+
+ if (!(sess_local = shared_malloc(sizeof(sessionlocalt) * MAXSESSION)))
+ {
+ LOG(0, 0, 0, "Error doing malloc for sess_local: %s\n", strerror(errno));
+ exit(1);
+ }
+
+ if (!(radius = shared_malloc(sizeof(radiust) * MAXRADIUS)))
+ {
+ LOG(0, 0, 0, "Error doing malloc for radius: %s\n", strerror(errno));
+ exit(1);
+ }
+
+ if (!(ip_address_pool = shared_malloc(sizeof(ippoolt) * MAXIPPOOL)))
+ {
+ LOG(0, 0, 0, "Error doing malloc for ip_address_pool: %s\n", strerror(errno));
+ exit(1);
+ }
+
+ if (!(ip_filters = shared_malloc(sizeof(ip_filtert) * MAXFILTER)))
+ {
+ LOG(0, 0, 0, "Error doing malloc for ip_filters: %s\n", strerror(errno));
+ exit(1);
+ }
+ memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
+
+ if (!(cli_session_actions = shared_malloc(sizeof(struct cli_session_actions) * MAXSESSION)))
+ {
+ LOG(0, 0, 0, "Error doing malloc for cli session actions: %s\n", strerror(errno));
+ exit(1);
+ }
+ memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
+
+ if (!(cli_tunnel_actions = shared_malloc(sizeof(struct cli_tunnel_actions) * MAXSESSION)))
+ {
+ LOG(0, 0, 0, "Error doing malloc for cli tunnel actions: %s\n", strerror(errno));
+ exit(1);
+ }
+ memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
+
+ memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
+ memset(session, 0, sizeof(sessiont) * MAXSESSION);
+ memset(radius, 0, sizeof(radiust) * MAXRADIUS);
+ memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
+
+ // Put all the sessions on the free list marked as undefined.
+ for (i = 1; i < MAXSESSION; i++)
+ {
+ session[i].next = i + 1;
+ session[i].tunnel = T_UNDEF; // mark it as not filled in.
+ }
+ session[MAXSESSION - 1].next = 0;
+ sessionfree = 1;
+
+ // Mark all the tunnels as undefined (waiting to be filled in by a download).
+ for (i = 1; i < MAXTUNNEL; i++)
+ tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
+
+ if (!*hostname)
+ {
+ // Grab my hostname unless it's been specified
+ gethostname(hostname, sizeof(hostname));
+ stripdomain(hostname);
+ }
+
+ _statistics->start_time = _statistics->last_reset = time(NULL);
+
+#ifdef BGP
+ if (!(bgp_peers = shared_malloc(sizeof(struct bgp_peer) * BGP_NUM_PEERS)))
+ {
+ LOG(0, 0, 0, "Error doing malloc for bgp: %s\n", strerror(errno));
+ exit(1);
+ }
+#endif /* BGP */
+}
+
+static int assign_ip_address(sessionidt s)
+{
+ uint32_t i;
+ int best = -1;
+ time_t best_time = time_now;
+ char *u = session[s].user;
+ char reuse = 0;
+
+
+ CSTAT(assign_ip_address);
+
+ for (i = 1; i < ip_pool_size; i++)
+ {
+ 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))
+ {
+ best = i;
+ reuse = 1;
+ break;
+ }
+
+ if (ip_address_pool[i].last < best_time)
+ {
+ best = i;
+ if (!(best_time = ip_address_pool[i].last))
+ break; // never used, grab this one
+ }
+ }
+
+ if (best < 0)
+ {
+ LOG(0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
+ return 0;
+ }
+
+ session[s].ip = ip_address_pool[best].address;
+ session[s].ip_pool_index = best;
+ ip_address_pool[best].assigned = 1;
+ ip_address_pool[best].last = time_now;
+ ip_address_pool[best].session = s;
+ if (session[s].walled_garden)
+ /* Don't track addresses of users in walled garden (note: this
+ means that their address isn't "sticky" even if they get
+ 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, s, session[s].tunnel, "assign_ip_address(): %s ip address %d from pool\n",
+ reuse ? "Reusing" : "Allocating", best);
+
+ return 1;
+}
+
+static void free_ip_address(sessionidt s)
+{
+ int i = session[s].ip_pool_index;
+
+
+ CSTAT(free_ip_address);
+
+ if (!session[s].ip)
+ return; // what the?
+
+ if (i < 0) // Is this actually part of the ip pool?
+ i = 0;
+
+ STAT(ip_freed);
+ cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
+ session[s].ip = 0;
+ ip_address_pool[i].assigned = 0;
+ ip_address_pool[i].session = 0;
+ ip_address_pool[i].last = time_now;
+}
+
+//
+// Fsck the address pool against the session table.
+// Normally only called when we become a master.
+//
+// This isn't perfect: We aren't keep tracking of which
+// users used to have an IP address.
+//
+void rebuild_address_pool(void)
+{
+ int i;
+
+ //
+ // Zero the IP pool allocation, and build
+ // a map from IP address to pool index.
+ for (i = 1; i < MAXIPPOOL; ++i)
+ {
+ ip_address_pool[i].assigned = 0;
+ ip_address_pool[i].session = 0;
+ if (!ip_address_pool[i].address)
+ continue;
+
+ cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
+ }
+
+ for (i = 0; i < MAXSESSION; ++i)
+ {
+ int ipid;
+ if (!(session[i].opened && session[i].ip))
+ continue;
+
+ ipid = - lookup_ipmap(htonl(session[i].ip));
+
+ if (session[i].ip_pool_index < 0)
+ {
+ // Not allocated out of the pool.
+ if (ipid < 1) // Not found in the pool either? good.
+ continue;
+
+ LOG(0, i, 0, "Session %d has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
+ i, fmtaddr(session[i].ip, 0), ipid);
+
+ // Fall through and process it as part of the pool.
+ }
+
+
+ if (ipid > MAXIPPOOL || ipid < 0)
+ {
+ LOG(0, i, 0, "Session %d has a pool IP that's not found in the pool! (%d)\n", i, ipid);
+ ipid = -1;
+ session[i].ip_pool_index = ipid;
+ continue;
+ }
+
+ ip_address_pool[ipid].assigned = 1;
+ ip_address_pool[ipid].session = i;
+ ip_address_pool[ipid].last = time_now;
+ strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
+ session[i].ip_pool_index = ipid;
+ cache_ipmap(session[i].ip, i); // Fix the ip map.
+ }
+}
+
+//
+// Fix the address pool to match a changed session.
+// (usually when the master sends us an update).
+static void fix_address_pool(int sid)
+{
+ int ipid;
+
+ ipid = session[sid].ip_pool_index;
+
+ if (ipid > ip_pool_size)
+ return; // Ignore it. rebuild_address_pool will fix it up.
+
+ if (ip_address_pool[ipid].address != session[sid].ip)
+ return; // Just ignore it. rebuild_address_pool will take care of it.
+
+ ip_address_pool[ipid].assigned = 1;
+ ip_address_pool[ipid].session = sid;
+ ip_address_pool[ipid].last = time_now;
+ strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
+}
+
+//
+// Add a block of addresses to the IP pool to hand out.
+//
+static void add_to_ip_pool(in_addr_t addr, in_addr_t mask)
+{
+ int i;
+ if (mask == 0)
+ mask = 0xffffffff; // Host route only.
+
+ addr &= mask;
+
+ if (ip_pool_size >= MAXIPPOOL) // Pool is full!
+ return ;
+
+ for (i = addr ;(i & mask) == addr; ++i)
+ {
+ if ((i & 0xff) == 0 || (i&0xff) == 255)
+ continue; // Skip 0 and broadcast addresses.
+
+ ip_address_pool[ip_pool_size].address = i;
+ ip_address_pool[ip_pool_size].assigned = 0;
+ ++ip_pool_size;
+ if (ip_pool_size >= MAXIPPOOL)
+ {
+ LOG(0, 0, 0, "Overflowed IP pool adding %s\n", fmtaddr(htonl(addr), 0));
+ return;
+ }
+ }
+}
+
+// Initialize the IP address pool
+static void initippool()
+{
+ FILE *f;
+ char *p;
+ char buf[4096];
+ memset(ip_address_pool, 0, sizeof(ip_address_pool));
+
+ if (!(f = fopen(IPPOOLFILE, "r")))
+ {
+ LOG(0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
+ exit(1);
+ }
+
+ while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
+ {
+ char *pool = buf;
+ buf[4095] = 0; // Force it to be zero terminated/
+
+ if (*buf == '#' || *buf == '\n')
+ continue; // Skip comments / blank lines
+ if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
+ if ((p = (char *)strchr(buf, ':')))
+ {
+ in_addr_t src;
+ *p = '\0';
+ src = inet_addr(buf);
+ if (src == INADDR_NONE)
+ {
+ LOG(0, 0, 0, "Invalid address pool IP %s\n", buf);
+ exit(1);
+ }
+ // This entry is for a specific IP only
+ if (src != config->bind_address)
+ continue;
+ *p = ':';
+ pool = p+1;
+ }
+ if ((p = (char *)strchr(pool, '/')))
+ {
+ // It's a range
+ int numbits = 0;
+ in_addr_t start = 0, mask = 0;
+
+ LOG(2, 0, 0, "Adding IP address range %s\n", buf);
+ *p++ = 0;
+ if (!*p || !(numbits = atoi(p)))
+ {
+ LOG(0, 0, 0, "Invalid pool range %s\n", buf);
+ continue;
+ }
+ start = ntohl(inet_addr(pool));
+ mask = (in_addr_t) (pow(2, numbits) - 1) << (32 - numbits);
+
+ // Add a static route for this pool
+ LOG(5, 0, 0, "Adding route for address pool %s/%u\n",
+ fmtaddr(htonl(start), 0), 32 + mask);
+
+ routeset(0, start, mask, 0, 1);
+
+ add_to_ip_pool(start, mask);
+ }
+ else
+ {
+ // It's a single ip address
+ add_to_ip_pool(ntohl(inet_addr(pool)), 0);
+ }
+ }
+ fclose(f);
+ LOG(1, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
+}
+
+void snoop_send_packet(uint8_t *packet, uint16_t size, in_addr_t destination, uint16_t port)
+{
+ struct sockaddr_in snoop_addr = {0};
+ if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
+ return;
+
+ snoop_addr.sin_family = AF_INET;
+ snoop_addr.sin_addr.s_addr = destination;
+ snoop_addr.sin_port = ntohs(port);
+
+ LOG(5, 0, 0, "Snooping %d byte packet to %s:%d\n", size,
+ fmtaddr(snoop_addr.sin_addr.s_addr, 0),
+ htons(snoop_addr.sin_port));
+
+ if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
+ LOG(0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
+
+ STAT(packets_snooped);
+}
+
+static int dump_session(FILE **f, sessiont *s)
+{
+ if (!s->opened || !s->ip || !(s->cin_delta || s->cout_delta) || !*s->user || s->walled_garden)
+ return 1;
+
+ if (!*f)
+ {
+ char filename[1024];
+ char timestr[64];
+ time_t now = time(NULL);
+
+ strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(&now));
+ snprintf(filename, sizeof(filename), "%s/%s", config->accounting_dir, timestr);
+
+ if (!(*f = fopen(filename, "w")))
+ {
+ LOG(0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
+ return 0;
+ }
+
+ LOG(3, 0, 0, "Dumping accounting information to %s\n", filename);
+ fprintf(*f, "# dslwatch.pl dump file V1.01\n"
+ "# host: %s\n"
+ "# endpoint: %s\n"
+ "# time: %ld\n"
+ "# uptime: %ld\n"
+ "# format: username ip qos uptxoctets downrxoctets\n",
+ hostname,
+ fmtaddr(config->bind_address ? config->bind_address : my_address, 0),
+ now,
+ now - basetime);
+ }
+
+ LOG(4, 0, 0, "Dumping accounting information for %s\n", s->user);
+ fprintf(*f, "%s %s %d %u %u\n",
+ s->user, // username
+ fmtaddr(htonl(s->ip), 0), // ip
+ (s->throttle_in || s->throttle_out) ? 2 : 1, // qos
+ (uint32_t) s->cin_delta, // uptxoctets
+ (uint32_t) s->cout_delta); // downrxoctets
+
+ s->cin_delta = s->cout_delta = 0;
+
+ return 1;
+}
+
+static void dump_acct_info(int all)
+{
+ int i;
+ FILE *f = NULL;
+
+
+ CSTAT(dump_acct_info);
+
+ if (shut_acct_n)
+ {
+ for (i = 0; i < shut_acct_n; i++)
+ dump_session(&f, &shut_acct[i]);
+
+ shut_acct_n = 0;
+ }
+
+ if (all)
+ for (i = 1; i <= config->cluster_highest_sessionid; i++)
+ dump_session(&f, &session[i]);
+
+ if (f)
+ fclose(f);
+}
+
+// Main program
+int main(int argc, char *argv[])
+{
+ int i;
+ int optdebug = 0;
+ char *optconfig = CONFIGFILE;
+
+ time(&basetime); // start clock
+
+ // scan args
+ while ((i = getopt(argc, argv, "dvc:h:")) >= 0)
+ {
+ switch (i)
+ {
+ case 'd':
+ if (fork()) exit(0);
+ setsid();
+ freopen("/dev/null", "r", stdin);
+ freopen("/dev/null", "w", stdout);
+ freopen("/dev/null", "w", stderr);
+ break;
+ case 'v':
+ optdebug++;
+ break;
+ case 'c':
+ optconfig = optarg;
+ break;
+ case 'h':
+ snprintf(hostname, sizeof(hostname), "%s", optarg);
+ break;
+ default:
+ printf("Args are:\n"
+ "\t-d\t\tDetach from terminal\n"
+ "\t-c <file>\tConfig file\n"
+ "\t-h <hostname>\tForce hostname\n"
+ "\t-v\t\tDebug\n");
+
+ return (0);
+ break;
+ }
+ }
+
+ // Start the timer routine off
+ time(&time_now);
+ strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
+
+ initplugins();
+ initdata(optdebug, optconfig);
+
+ init_cli(hostname);
+ read_config_file();
+ update_config();
+ init_tbf(config->num_tbfs);
+
+ LOG(0, 0, 0, "L2TPNS version " VERSION "\n");
+ LOG(0, 0, 0, "Copyright (c) 2003, 2004, 2005 Optus Internet Engineering\n");
+ LOG(0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
+ {
+ struct rlimit rlim;
+ 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, "Can't set ulimit: %s\n", strerror(errno));
+
+ // Make core dumps go to /tmp
+ chdir("/tmp");
+ }
+
+ if (config->scheduler_fifo)
+ {
+ int ret;
+ struct sched_param params = {0};
+ params.sched_priority = 1;
+
+ if (get_nprocs() < 2)
+ {
+ LOG(0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
+ config->scheduler_fifo = 0;
+ }
+ else
+ {
+ if ((ret = sched_setscheduler(0, SCHED_FIFO, ¶ms)) == 0)
+ {
+ LOG(1, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
+ }
+ else
+ {
+ LOG(0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
+ config->scheduler_fifo = 0;
+ }
+ }
+ }
+
+ /* Set up the cluster communications port. */
+ if (cluster_init() < 0)
+ exit(1);
+
+ inittun();
+ LOG(1, 0, 0, "Set up on interface %s\n", config->tundevice);
+
+ initudp();
+ initrad();
+ initippool();
+
+ // seed prng
+ {
+ unsigned seed = time_now ^ getpid();
+ LOG(4, 0, 0, "Seeding the pseudo random generator: %u\n", seed);
+ srand(seed);
+ }
+
+ signal(SIGHUP, sighup_handler);
+ signal(SIGCHLD, sigchild_handler);
+ signal(SIGTERM, shutdown_handler);
+ signal(SIGINT, shutdown_handler);
+ signal(SIGQUIT, shutdown_handler);
+
+ // Prevent us from getting paged out
+ if (config->lock_pages)
+ {
+ if (!mlockall(MCL_CURRENT))
+ LOG(1, 0, 0, "Locking pages into memory\n");
+ else
+ LOG(0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
+ }
+
+ // Drop privileges here
+ if (config->target_uid > 0 && geteuid() == 0)
+ setuid(config->target_uid);
+
+ mainloop();
+
+ /* remove plugins (so cleanup code gets run) */
+ plugins_done();
+
+ // Remove the PID file if we wrote it
+ if (config->wrote_pid && *config->pid_file == '/')
+ unlink(config->pid_file);
+
+ /* kill CLI children */
+ signal(SIGTERM, SIG_IGN);
+ kill(0, SIGTERM);
+ return 0;
+}
+
+static void sighup_handler(int sig)
+{
+ main_reload++;
+}
+
+static void shutdown_handler(int sig)
+{
+ main_quit = (sig == SIGQUIT) ? QUIT_SHUTDOWN : QUIT_FAILOVER;
+}
+
+static void sigchild_handler(int sig)
+{
+ while (waitpid(-1, NULL, WNOHANG) > 0)
+ ;
+}
+
+static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response)
+{
+ MD5_CTX ctx;
+ *challenge_response = NULL;
+
+ if (!*config->l2tp_secret)
+ {
+ LOG(0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
+ return;
+ }
+
+ LOG(4, 0, 0, " Building challenge response for CHAP request\n");
+
+ *challenge_response = calloc(17, 1);
+
+ MD5_Init(&ctx);
+ MD5_Update(&ctx, &id, 1);
+ MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
+ MD5_Update(&ctx, challenge, challenge_length);
+ MD5_Final(*challenge_response, &ctx);
+
+ return;
+}
+
+static int facility_value(char *name)
+{
+ int i;
+ for (i = 0; facilitynames[i].c_name; i++)
+ {
+ if (strcmp(facilitynames[i].c_name, name) == 0)
+ return facilitynames[i].c_val;
+ }
+ return 0;
+}
+
+static void update_config()
+{
+ int i;
+ char *p;
+ static int timeout = 0;
+ static int interval = 0;
+
+ // Update logging
+ closelog();
+ syslog_log = 0;
+ if (log_stream)
+ {
+ if (log_stream != stderr)
+ fclose(log_stream);
+
+ log_stream = NULL;
+ }
+
+ if (*config->log_filename)
+ {
+ if (strstr(config->log_filename, "syslog:") == config->log_filename)
+ {
+ char *p = config->log_filename + 7;
+ if (*p)
+ {
+ openlog("l2tpns", LOG_PID, facility_value(p));
+ syslog_log = 1;
+ }
+ }
+ else if (strchr(config->log_filename, '/') == config->log_filename)
+ {
+ if ((log_stream = fopen((char *)(config->log_filename), "a")))
+ {
+ fseek(log_stream, 0, SEEK_END);
+ setbuf(log_stream, NULL);
+ }
+ else
+ {
+ log_stream = stderr;
+ setbuf(log_stream, NULL);
+ }
+ }
+ }
+ else
+ {
+ log_stream = stderr;
+ setbuf(log_stream, NULL);
+ }
+
+#define L2TP_HDRS (20+8+6+4) // L2TP data encaptulation: ip + udp + l2tp (data) + ppp (inc hdlc)
+#define TCP_HDRS (20+20) // TCP encapsulation: ip + tcp
+
+ if (config->l2tp_mtu <= 0) config->l2tp_mtu = 1500; // ethernet default
+ else if (config->l2tp_mtu < MINMTU) config->l2tp_mtu = MINMTU;
+ else if (config->l2tp_mtu > MAXMTU) config->l2tp_mtu = MAXMTU;
+
+ // reset MRU/MSS globals
+ MRU = config->l2tp_mtu - L2TP_HDRS;
+ if (MRU > PPPoE_MRU)
+ MRU = PPPoE_MRU;
+
+ MSS = MRU - TCP_HDRS;
+
+ // Update radius
+ config->numradiusservers = 0;
+ for (i = 0; i < MAXRADSERVER; i++)
+ if (config->radiusserver[i])
+ {
+ config->numradiusservers++;
+ // Set radius port: if not set, take the port from the
+ // first radius server. For the first radius server,
+ // take the #defined default value from l2tpns.h
+
+ // test twice, In case someone works with
+ // a secondary radius server without defining
+ // a primary one, this will work even then.
+ if (i > 0 && !config->radiusport[i])
+ config->radiusport[i] = config->radiusport[i-1];
+ if (!config->radiusport[i])
+ config->radiusport[i] = RADPORT;
+ }
+
+ if (!config->numradiusservers)
+ LOG(0, 0, 0, "No RADIUS servers defined!\n");
+
+ // parse radius_authtypes_s
+ config->radius_authtypes = config->radius_authprefer = 0;
+ p = config->radius_authtypes_s;
+ while (p && *p)
+ {
+ char *s = strpbrk(p, " \t,");
+ int type = 0;
+
+ if (s)
+ {
+ *s++ = 0;
+ while (*s == ' ' || *s == '\t')
+ s++;
+
+ if (!*s)
+ s = 0;
+ }
+
+ if (!strncasecmp("chap", p, strlen(p)))
+ type = AUTHCHAP;
+ else if (!strncasecmp("pap", p, strlen(p)))
+ type = AUTHPAP;
+ else
+ LOG(0, 0, 0, "Invalid RADIUS authentication type \"%s\"\n", p);
+
+ config->radius_authtypes |= type;
+ if (!config->radius_authprefer)
+ config->radius_authprefer = type;
+
+ p = s;
+ }
+
+ if (!config->radius_authtypes)
+ {
+ LOG(0, 0, 0, "Defaulting to PAP authentication\n");
+ config->radius_authtypes = config->radius_authprefer = AUTHPAP;
+ }
+
+ // normalise radius_authtypes_s
+ if (config->radius_authprefer == AUTHPAP)
+ {
+ strcpy(config->radius_authtypes_s, "pap");
+ if (config->radius_authtypes & AUTHCHAP)
+ strcat(config->radius_authtypes_s, ", chap");
+ }
+ else
+ {
+ strcpy(config->radius_authtypes_s, "chap");
+ if (config->radius_authtypes & AUTHPAP)
+ strcat(config->radius_authtypes_s, ", pap");
+ }
+
+ if (!config->radius_dae_port)
+ config->radius_dae_port = DAEPORT;
+
+ // re-initialise the random number source
+ initrandom(config->random_device);
+
+ // Update plugins
+ for (i = 0; i < MAXPLUGINS; i++)
+ {
+ if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
+ continue;
+
+ if (*config->plugins[i])
+ {
+ // Plugin added
+ add_plugin(config->plugins[i]);
+ }
+ else if (*config->old_plugins[i])
+ {
+ // Plugin removed
+ remove_plugin(config->old_plugins[i]);
+ }
+ }
+
+ memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
+ if (!config->multi_read_count) config->multi_read_count = 10;
+ if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
+ if (!*config->cluster_interface)
+ strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
+
+ if (!config->cluster_hb_interval)
+ config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
+
+ if (!config->cluster_hb_timeout)
+ config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
+
+ if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
+ {
+ // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
+ // late, ensure we're sufficiently larger than that
+ int t = 4 * config->cluster_hb_interval + 11;
+
+ if (config->cluster_hb_timeout < t)
+ {
+ LOG(0, 0, 0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
+ config->cluster_hb_timeout = t;
+ }
+
+ // Push timing changes to the slaves immediately if we're the master
+ if (config->cluster_iam_master)
+ cluster_heartbeat();
+
+ interval = config->cluster_hb_interval;
+ timeout = config->cluster_hb_timeout;
+ }
+
+ // Write PID file
+ if (*config->pid_file == '/' && !config->wrote_pid)
+ {
+ FILE *f;
+ if ((f = fopen(config->pid_file, "w")))
+ {
+ fprintf(f, "%d\n", getpid());
+ fclose(f);
+ config->wrote_pid = 1;
+ }
+ else
+ {
+ LOG(0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
+ }
+ }
+}
+
+static 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, "Reading config file %s\n", config->config_file);
+ cli_do_file(f);
+ LOG(3, 0, 0, "Done reading config file\n");
+ fclose(f);
+}
+
+int sessionsetup(sessionidt s, tunnelidt t)
+{
+ // A session now exists, set it up
+ in_addr_t ip;
+ char *user;
+ sessionidt i;
+ int r;
+
+ CSTAT(sessionsetup);
+
+ LOG(3, s, t, "Doing session setup for session\n");
+
+ if (!session[s].ip)
+ {
+ assign_ip_address(s);
+ if (!session[s].ip)
+ {
+ LOG(0, s, t, " No IP allocated. The IP address pool is FULL!\n");
+ sessionshutdown(s, "No IP addresses available.", CDN_TRY_ANOTHER, TERM_SERVICE_UNAVAILABLE);
+ return 0;
+ }
+ LOG(3, s, t, " No IP allocated. Assigned %s from pool\n",
+ fmtaddr(htonl(session[s].ip), 0));
+ }
+
+
+ // Make sure this is right
+ session[s].tunnel = t;
+
+ // zap old sessions with same IP and/or username
+ // Don't kill gardened sessions - doing so leads to a DoS
+ // from someone who doesn't need to know the password
+ {
+ ip = session[s].ip;
+ user = session[s].user;
+ for (i = 1; i <= config->cluster_highest_sessionid; i++)
+ {
+ if (i == s) continue;
+ if (!session[s].opened) continue;
+ if (ip == session[i].ip)
+ {
+ sessionkill(i, "Duplicate IP address");
+ continue;
+ }
+
+ if (config->allow_duplicate_users) continue;
+ if (session[s].walled_garden || session[i].walled_garden) continue;
+ if (!strcasecmp(user, session[i].user))
+ sessionkill(i, "Duplicate session for users");
+ }
+ }
+
+ {
+ int routed = 0;
+
+ // Add the route for this session.
+ for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
+ {
+ if ((session[s].ip & session[s].route[r].mask) ==
+ (session[s].route[r].ip & session[s].route[r].mask))
+ routed++;
+
+ routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 1);
+ }
+
+ // Static IPs need to be routed if not already
+ // convered by a Framed-Route. Anything else is part
+ // of the IP address pool and is already routed, it
+ // just needs to be added to the IP cache.
+ // IPv6 route setup is done in ppp.c, when IPV6CP is acked.
+ if (session[s].ip_pool_index == -1) // static ip
+ {
+ if (!routed) routeset(s, session[s].ip, 0, 0, 1);
+ }
+ else
+ cache_ipmap(session[s].ip, s);
+ }
+
+ sess_local[s].lcp_authtype = 0; // RADIUS authentication complete
+ lcp_open(s, t); // transition to Network phase and send initial IPCP
+
+ // Run the plugin's against this new session.
+ {
+ struct param_new_session data = { &tunnel[t], &session[s] };
+ run_plugins(PLUGIN_NEW_SESSION, &data);
+ }
+
+ // Allocate TBFs if throttled
+ if (session[s].throttle_in || session[s].throttle_out)
+ throttle_session(s, session[s].throttle_in, session[s].throttle_out);
+
+ session[s].last_packet = time_now;
+
+ LOG(2, s, t, "Login by %s at %s from %s (%s)\n", session[s].user,
+ fmtaddr(htonl(session[s].ip), 0),
+ fmtaddr(htonl(tunnel[t].ip), 1), tunnel[t].hostname);
+
+ cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
+
+ return 1; // RADIUS OK and IP allocated, done...
+}
+
+//
+// This session just got dropped on us by the master or something.
+// Make sure our tables up up to date...
+//
+int load_session(sessionidt s, sessiont *new)
+{
+ int i;
+ int newip = 0;
+
+ // Sanity checks.
+ if (new->ip_pool_index >= MAXIPPOOL ||
+ new->tunnel >= MAXTUNNEL)
+ {
+ LOG(0, s, 0, "Strange session update received!\n");
+ // FIXME! What to do here?
+ return 0;
+ }
+
+ //
+ // Ok. All sanity checks passed. Now we're committed to
+ // loading the new session.
+ //
+
+ session[s].tunnel = new->tunnel; // For logging in cache_ipmap
+
+ // See if routes/ip cache need updating
+ if (new->ip != session[s].ip)
+ newip++;
+
+ for (i = 0; !newip && i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
+ if (new->route[i].ip != session[s].route[i].ip ||
+ new->route[i].mask != session[s].route[i].mask)
+ newip++;
+
+ // needs update
+ if (newip)
+ {
+ int routed = 0;
+
+ // remove old routes...
+ for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
+ {
+ if ((session[s].ip & session[s].route[i].mask) ==
+ (session[s].route[i].ip & session[s].route[i].mask))
+ routed++;
+
+ routeset(s, session[s].route[i].ip, session[s].route[i].mask, 0, 0);
+ }
+
+ // ...ip
+ if (session[s].ip)
+ {
+ if (session[s].ip_pool_index == -1) // static IP
+ {
+ if (!routed) routeset(s, session[s].ip, 0, 0, 0);
+ }
+ else // It's part of the IP pool, remove it manually.
+ uncache_ipmap(session[s].ip);
+ }
+
+ routed = 0;
+
+ // add new routes...
+ for (i = 0; i < MAXROUTE && new->route[i].ip; i++)
+ {
+ if ((new->ip & new->route[i].mask) ==
+ (new->route[i].ip & new->route[i].mask))
+ routed++;
+
+ routeset(s, new->route[i].ip, new->route[i].mask, 0, 1);
+ }
+
+ // ...ip
+ if (new->ip)
+ {
+ // If there's a new one, add it.
+ if (new->ip_pool_index == -1)
+ {
+ if (!routed) routeset(s, new->ip, 0, 0, 1);
+ }
+ else
+ cache_ipmap(new->ip, s);
+ }
+ }
+
+ // check v6 routing
+ if (new->ipv6prefixlen && new->ppp.ipv6cp == Opened && session[s].ppp.ipv6cp != Opened)
+ route6set(s, new->ipv6route, new->ipv6prefixlen, 1);
+
+ // check filters
+ if (new->filter_in && (new->filter_in > MAXFILTER || !ip_filters[new->filter_in - 1].name[0]))
+ {
+ LOG(2, s, session[s].tunnel, "Dropping invalid input filter %d\n", (int) new->filter_in);
+ new->filter_in = 0;
+ }
+
+ if (new->filter_out && (new->filter_out > MAXFILTER || !ip_filters[new->filter_out - 1].name[0]))
+ {
+ LOG(2, s, session[s].tunnel, "Dropping invalid output filter %d\n", (int) new->filter_out);
+ new->filter_out = 0;
+ }
+
+ if (new->filter_in != session[s].filter_in)
+ {
+ if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
+ if (new->filter_in) ip_filters[new->filter_in - 1].used++;
+ }
+
+ if (new->filter_out != session[s].filter_out)
+ {
+ if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
+ if (new->filter_out) ip_filters[new->filter_out - 1].used++;
+ }
+
+ if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
+ // for walking the sessions to forward byte counts to the master.
+ config->cluster_highest_sessionid = s;
+
+ memcpy(&session[s], new, sizeof(session[s])); // Copy over..
+
+ // Do fixups into address pool.
+ if (new->ip_pool_index != -1)
+ fix_address_pool(s);
+
+ return 1;
+}
+
+static void initplugins()
+{
+ int i;
+
+ loaded_plugins = ll_init();
+ // Initialize the plugins to nothing
+ for (i = 0; i < MAX_PLUGIN_TYPES; i++)
+ plugins[i] = ll_init();
+}
+
+static void *open_plugin(char *plugin_name, int load)
+{
+ char path[256] = "";
+
+ snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
+ LOG(2, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
+ return dlopen(path, RTLD_NOW);
+}
+
+// plugin callback to get a config value
+static void *getconfig(char *key, enum config_typet type)
+{
+ int i;
+
+ for (i = 0; config_values[i].key; i++)
+ {
+ if (!strcmp(config_values[i].key, key))
+ {
+ if (config_values[i].type == type)
+ return ((void *) config) + config_values[i].offset;
+
+ LOG(1, 0, 0, "plugin requested config item \"%s\" expecting type %d, have type %d\n",
+ key, type, config_values[i].type);
+
+ return 0;
+ }
+ }
+
+ LOG(1, 0, 0, "plugin requested unknown config item \"%s\"\n", key);
+ return 0;
+}
+
+static int add_plugin(char *plugin_name)
+{
+ static struct pluginfuncs funcs = {
+ _log,
+ _log_hex,
+ fmtaddr,
+ sessionbyuser,
+ sessiontbysessionidt,
+ sessionidtbysessiont,
+ radiusnew,
+ radiussend,
+ getconfig,
+ sessionshutdown,
+ sessionkill,
+ throttle_session,
+ cluster_send_session,
+ };
+
+ void *p = open_plugin(plugin_name, 1);
+ int (*initfunc)(struct pluginfuncs *);
+ int i;
+
+ if (!p)
+ {
+ LOG(1, 0, 0, " Plugin load failed: %s\n", dlerror());
+ return -1;
+ }
+
+ if (ll_contains(loaded_plugins, p))
+ {
+ dlclose(p);
+ return 0; // already loaded
+ }
+
+ {
+ int *v = dlsym(p, "plugin_api_version");
+ if (!v || *v != PLUGIN_API_VERSION)
+ {
+ LOG(1, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
+ dlclose(p);
+ return -1;
+ }
+ }
+
+ if ((initfunc = dlsym(p, "plugin_init")))
+ {
+ if (!initfunc(&funcs))
+ {
+ LOG(1, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
+ dlclose(p);
+ return -1;
+ }
+ }
+
+ ll_push(loaded_plugins, p);
+
+ for (i = 0; i < max_plugin_functions; i++)
+ {
+ void *x;
+ if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
+ {
+ LOG(3, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
+ ll_push(plugins[i], x);
+ }
+ }
+
+ LOG(2, 0, 0, " Loaded plugin %s\n", plugin_name);
+ return 1;
+}
+
+static void run_plugin_done(void *plugin)
+{
+ int (*donefunc)(void) = dlsym(plugin, "plugin_done");
+
+ if (donefunc)
+ donefunc();
+}
+
+static int remove_plugin(char *plugin_name)
+{
+ void *p = open_plugin(plugin_name, 0);
+ int loaded = 0;
+
+ if (!p)
+ return -1;
+
+ if (ll_contains(loaded_plugins, p))
+ {
+ int i;
+ for (i = 0; i < max_plugin_functions; i++)
+ {
+ void *x;
+ if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
+ ll_delete(plugins[i], x);
+ }
+
+ ll_delete(loaded_plugins, p);
+ run_plugin_done(p);
+ loaded = 1;
+ }
+
+ dlclose(p);
+ LOG(2, 0, 0, "Removed plugin %s\n", plugin_name);
+ return loaded;
+}
+
+int run_plugins(int plugin_type, void *data)
+{
+ int (*func)(void *data);
+
+ if (!plugins[plugin_type] || plugin_type > max_plugin_functions)
+ return PLUGIN_RET_ERROR;
+
+ ll_reset(plugins[plugin_type]);
+ while ((func = ll_next(plugins[plugin_type])))
+ {
+ int r = func(data);
+
+ if (r != PLUGIN_RET_OK)
+ return r; // stop here
+ }
+
+ return PLUGIN_RET_OK;
+}
+
+static void plugins_done()
+{
+ void *p;
+
+ ll_reset(loaded_plugins);
+ while ((p = ll_next(loaded_plugins)))
+ run_plugin_done(p);
+}
+
+static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen, struct in_addr *local)
+{
+ struct nsctl request;
+ struct nsctl response;
+ int type = unpack_control(&request, buf, len);
+ int r;
+ void *p;
+
+ if (log_stream && config->debug >= 4)
+ {
+ if (type < 0)
+ {
+ LOG(4, 0, 0, "Bogus control message from %s (%d)\n",
+ fmtaddr(addr->sin_addr.s_addr, 0), type);
+ }
+ else
+ {
+ LOG(4, 0, 0, "Received [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
+ dump_control(&request, log_stream);
+ }
+ }
+
+ switch (type)
+ {
+ case NSCTL_REQ_LOAD:
+ if (request.argc != 1)
+ {
+ response.type = NSCTL_RES_ERR;
+ response.argc = 1;
+ response.argv[0] = "name of plugin required";
+ }
+ else if ((r = add_plugin(request.argv[0])) < 1)
+ {
+ response.type = NSCTL_RES_ERR;
+ response.argc = 1;
+ response.argv[0] = !r
+ ? "plugin already loaded"
+ : "error loading plugin";
+ }
+ else
+ {
+ response.type = NSCTL_RES_OK;
+ response.argc = 0;
+ }
+
+ break;
+
+ case NSCTL_REQ_UNLOAD:
+ if (request.argc != 1)
+ {
+ response.type = NSCTL_RES_ERR;
+ response.argc = 1;
+ response.argv[0] = "name of plugin required";
+ }
+ else if ((r = remove_plugin(request.argv[0])) < 1)
+ {
+ response.type = NSCTL_RES_ERR;
+ response.argc = 1;
+ response.argv[0] = !r
+ ? "plugin not loaded"
+ : "plugin not found";
+ }
+ else
+ {
+ response.type = NSCTL_RES_OK;
+ response.argc = 0;
+ }
+
+ break;
+
+ case NSCTL_REQ_HELP:
+ response.type = NSCTL_RES_OK;
+ response.argc = 0;
+
+ ll_reset(loaded_plugins);
+ while ((p = ll_next(loaded_plugins)))
+ {
+ char **help = dlsym(p, "plugin_control_help");
+ while (response.argc < 0xff && help && *help)
+ response.argv[response.argc++] = *help++;
+ }
+
+ break;
+
+ case NSCTL_REQ_CONTROL:
+ {
+ struct param_control param = {
+ config->cluster_iam_master,
+ request.argc,
+ request.argv,
+ 0,
+ NULL,
+ };
+
+ int r = run_plugins(PLUGIN_CONTROL, ¶m);
+
+ if (r == PLUGIN_RET_ERROR)
+ {
+ response.type = NSCTL_RES_ERR;
+ response.argc = 1;
+ response.argv[0] = param.additional
+ ? param.additional
+ : "error returned by plugin";
+ }
+ else if (r == PLUGIN_RET_NOTMASTER)
+ {
+ static char msg[] = "must be run on master: 000.000.000.000";
+
+ response.type = NSCTL_RES_ERR;
+ response.argc = 1;
+ if (config->cluster_master_address)
+ {
+ strcpy(msg + 23, fmtaddr(config->cluster_master_address, 0));
+ response.argv[0] = msg;
+ }
+ else
+ {
+ response.argv[0] = "must be run on master: none elected";
+ }
+ }
+ else if (!(param.response & NSCTL_RESPONSE))
+ {
+ response.type = NSCTL_RES_ERR;
+ response.argc = 1;
+ response.argv[0] = param.response
+ ? "unrecognised response value from plugin"
+ : "unhandled action";
+ }
+ else
+ {
+ response.type = param.response;
+ response.argc = 0;
+ if (param.additional)
+ {
+ response.argc = 1;
+ response.argv[0] = param.additional;
+ }
+ }
+ }
+
+ break;
+
+ default:
+ response.type = NSCTL_RES_ERR;
+ response.argc = 1;
+ response.argv[0] = "error unpacking control packet";
+ }
+
+ buf = calloc(NSCTL_MAX_PKT_SZ, 1);
+ if (!buf)
+ {
+ LOG(2, 0, 0, "Failed to allocate nsctl response\n");
+ return;
+ }
+
+ r = pack_control(buf, NSCTL_MAX_PKT_SZ, response.type, response.argc, response.argv);
+ if (r > 0)
+ {
+ sendtofrom(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen, local);
+ if (log_stream && config->debug >= 4)
+ {
+ LOG(4, 0, 0, "Sent [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
+ dump_control(&response, log_stream);
+ }
+ }
+ else
+ LOG(2, 0, 0, "Failed to pack nsctl response for %s (%d)\n",
+ fmtaddr(addr->sin_addr.s_addr, 0), r);
+
+ free(buf);
+}
+
+static tunnelidt new_tunnel()
+{
+ tunnelidt i;
+ for (i = 1; i < MAXTUNNEL; i++)
+ {
+ if (tunnel[i].state == TUNNELFREE)
+ {
+ LOG(4, 0, i, "Assigning tunnel ID %d\n", i);
+ if (i > config->cluster_highest_tunnelid)
+ config->cluster_highest_tunnelid = i;
+ return i;
+ }
+ }
+ LOG(0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
+ return 0;
+}
+
+//
+// We're becoming the master. Do any required setup..
+//
+// This is principally telling all the plugins that we're
+// now a master, and telling them about all the sessions
+// that are active too..
+//
+void become_master(void)
+{
+ int s, i;
+ static struct event_data d[RADIUS_FDS];
+ struct epoll_event e;
+
+ run_plugins(PLUGIN_BECOME_MASTER, NULL);
+
+ // running a bunch of iptables commands is slow and can cause
+ // the master to drop tunnels on takeover--kludge around the
+ // problem by forking for the moment (note: race)
+ if (!fork_and_close())
+ {
+ for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
+ {
+ if (!session[s].opened) // Not an in-use session.
+ continue;
+
+ run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
+ }
+ exit(0);
+ }
+
+ // add radius fds
+ e.events = EPOLLIN;
+ for (i = 0; i < RADIUS_FDS; i++)
+ {
+ d[i].type = FD_TYPE_RADIUS;
+ d[i].index = i;
+ e.data.ptr = &d[i];
+
+ epoll_ctl(epollfd, EPOLL_CTL_ADD, radfds[i], &e);
+ }
+}
+
+int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
+{
+ int s, i;
+ int count = 0;
+ int buckets[64];
+
+ if (CLI_HELP_REQUESTED)
+ return CLI_HELP_NO_ARGS;
+
+ time(&time_now);
+ for (i = 0; i < 64;++i) buckets[i] = 0;
+
+ for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
+ {
+ int idle;
+ if (!session[s].opened)
+ continue;
+
+ idle = time_now - session[s].last_packet;
+ idle /= 5 ; // In multiples of 5 seconds.
+ if (idle < 0)
+ idle = 0;
+ if (idle > 63)
+ idle = 63;
+
+ ++count;
+ ++buckets[idle];
+ }
+
+ for (i = 0; i < 63; ++i)
+ {
+ cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
+ }
+ cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
+ cli_print(cli, "%d total sessions open.", count);
+ return CLI_OK;
+}
+
+int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
+{
+ int s, i;
+ int count = 0;
+ int buckets[64];
+
+ if (CLI_HELP_REQUESTED)
+ return CLI_HELP_NO_ARGS;
+
+ time(&time_now);
+ for (i = 0; i < 64;++i) buckets[i] = 0;
+
+ for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
+ {
+ int open = 0, d;
+ if (!session[s].opened)
+ continue;
+
+ d = time_now - session[s].opened;
+ if (d < 0)
+ d = 0;
+ while (d > 1 && open < 32)
+ {
+ ++open;
+ d >>= 1; // half.
+ }
+ ++count;
+ ++buckets[open];
+ }
+
+ s = 1;
+ for (i = 0; i < 30; ++i)
+ {
+ cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
+ s <<= 1;
+ }
+ cli_print(cli, "%d total sessions open.", count);
+ return CLI_OK;
+}
+
+/* Unhide an avp.
+ *
+ * This unencodes the AVP using the L2TP secret and the previously
+ * stored random vector. It overwrites the hidden data with the
+ * unhidden AVP subformat.
+ */
+static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len)
+{
+ MD5_CTX ctx;
+ uint8_t digest[16];
+ uint8_t *last;
+ size_t d = 0;
+ uint16_t m = htons(type);
+
+ // Compute initial pad
+ MD5_Init(&ctx);
+ MD5_Update(&ctx, (unsigned char *) &m, 2);
+ MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
+ MD5_Update(&ctx, vector, vec_len);
+ MD5_Final(digest, &ctx);
+
+ // pointer to last decoded 16 octets
+ last = value;
+
+ while (len > 0)
+ {
+ // calculate a new pad based on the last decoded block
+ if (d >= sizeof(digest))
+ {
+ MD5_Init(&ctx);
+ MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
+ MD5_Update(&ctx, last, sizeof(digest));
+ MD5_Final(digest, &ctx);
+
+ d = 0;
+ last = value;
+ }
+
+ *value++ ^= digest[d++];
+ len--;
+ }
+}
+
+int find_filter(char const *name, size_t len)
+{
+ int free = -1;
+ int i;
+
+ for (i = 0; i < MAXFILTER; i++)
+ {
+ if (!*ip_filters[i].name)
+ {
+ if (free < 0)
+ free = i;
+
+ continue;
+ }
+
+ if (strlen(ip_filters[i].name) != len)
+ continue;
+
+ if (!strncmp(ip_filters[i].name, name, len))
+ return i;
+ }
+
+ return free;
+}
+
+static int ip_filter_port(ip_filter_portt *p, uint16_t port)
+{
+ switch (p->op)
+ {
+ case FILTER_PORT_OP_EQ: return port == p->port;
+ case FILTER_PORT_OP_NEQ: return port != p->port;
+ case FILTER_PORT_OP_GT: return port > p->port;
+ case FILTER_PORT_OP_LT: return port < p->port;
+ case FILTER_PORT_OP_RANGE: return port >= p->port && port <= p->port2;
+ }
+
+ return 0;
+}
+
+static int ip_filter_flag(uint8_t op, uint8_t sflags, uint8_t cflags, uint8_t flags)
+{
+ switch (op)
+ {
+ case FILTER_FLAG_OP_ANY:
+ return (flags & sflags) || (~flags & cflags);
+
+ case FILTER_FLAG_OP_ALL:
+ return (flags & sflags) == sflags && (~flags & cflags) == cflags;
+
+ case FILTER_FLAG_OP_EST:
+ return (flags & (TCP_FLAG_ACK|TCP_FLAG_RST)) && (~flags & TCP_FLAG_SYN);
+ }
+
+ return 0;
+}
+
+int ip_filter(uint8_t *buf, int len, uint8_t filter)
+{
+ uint16_t frag_offset;
+ uint8_t proto;
+ in_addr_t src_ip;
+ in_addr_t dst_ip;
+ uint16_t src_port = 0;
+ uint16_t dst_port = 0;
+ uint8_t flags = 0;
+ ip_filter_rulet *rule;
+
+ if (len < 20) // up to end of destination address
+ return 0;
+
+ if ((*buf >> 4) != 4) // IPv4
+ return 0;
+
+ frag_offset = ntohs(*(uint16_t *) (buf + 6)) & 0x1fff;
+ proto = buf[9];
+ src_ip = *(in_addr_t *) (buf + 12);
+ dst_ip = *(in_addr_t *) (buf + 16);
+
+ if (frag_offset == 0 && (proto == IPPROTO_TCP || proto == IPPROTO_UDP))
+ {
+ int l = (buf[0] & 0xf) * 4; // length of IP header
+ if (len < l + 4) // ports
+ return 0;
+
+ src_port = ntohs(*(uint16_t *) (buf + l));
+ dst_port = ntohs(*(uint16_t *) (buf + l + 2));
+ if (proto == IPPROTO_TCP)
+ {
+ if (len < l + 14) // flags
+ return 0;
+
+ flags = buf[l + 13] & 0x3f;
+ }
+ }
+
+ for (rule = ip_filters[filter].rules; rule->action; rule++)
+ {
+ if (rule->proto != IPPROTO_IP && proto != rule->proto)
+ continue;
+
+ if (rule->src_wild != INADDR_BROADCAST &&
+ (src_ip & ~rule->src_wild) != (rule->src_ip & ~rule->src_wild))
+ continue;
+
+ if (rule->dst_wild != INADDR_BROADCAST &&
+ (dst_ip & ~rule->dst_wild) != (rule->dst_ip & ~rule->dst_wild))
+ continue;
+
+ if (frag_offset)
+ {
+ // layer 4 deny rules are skipped
+ if (rule->action == FILTER_ACTION_DENY &&
+ (rule->src_ports.op || rule->dst_ports.op || rule->tcp_flag_op))
+ continue;
+ }
+ else
+ {
+ if (rule->frag)
+ continue;
+
+ if (proto == IPPROTO_TCP || proto == IPPROTO_UDP)
+ {
+ if (rule->src_ports.op && !ip_filter_port(&rule->src_ports, src_port))
+ continue;
+
+ if (rule->dst_ports.op && !ip_filter_port(&rule->dst_ports, dst_port))
+ continue;
+
+ if (proto == IPPROTO_TCP && rule->tcp_flag_op &&
+ !ip_filter_flag(rule->tcp_flag_op, rule->tcp_sflags, rule->tcp_cflags, flags))
+ continue;
+ }
+ }
+
+ // matched
+ rule->counter++;
+ return rule->action == FILTER_ACTION_PERMIT;
+ }
+
+ // default deny
+ return 0;
+}
projects / l2tpns.git / commitdiff