// L2TP Network Server // Adrian Kennard 2002 // Copyright (c) 2003, 2004, 2005, 2006 Optus Internet Engineering // Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced // vim: sw=8 ts=8 #include #include #include #include #include #define SYSLOG_NAMES #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "md5.h" #include "dhcp6.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 #include "l2tplac.h" #include "pppoe.h" #include "dhcp6.h" char * Vendor_name = "Linux L2TPNS"; uint32_t call_serial_number = 0; // Globals configt *config = NULL; // all configuration int nlfd = -1; // netlink socket int tunfd = -1; // tun interface file handle. (network device) int udpfd[MAX_UDPFD + 1] = INIT_TABUDPFD; // array UDP file handle + 1 for lac udp int udplacfd = -1; // UDP LAC 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 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[MAXHOSTNAME] = ""; // us. static int tunidx; // ifr_ifindex of tun device int nlseqnum = 0; // netlink sequence number int min_initok_nlseqnum = 0; // minimun seq number for messages after init is ok 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 // Guest change char guest_users[10][32]; // Array of guest users int guest_accounts_num = 0; // Number of guest users // 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 union iphash { sessionidt sess; union iphash *idx; } ip_hash[256]; // Mapping from IP address to session structures. struct ipv6radix { sessionidt sess; struct ipv6radix *branch; } ipv6_hash[16]; // 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. uint64_t time_now_ms = 0; // Current time in milliseconds 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("ppp_keepalive", ppp_keepalive, BOOL), 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("radius_bind_min", radius_bind_min, SHORT), CONFIG("radius_bind_max", radius_bind_max, SHORT), CONFIG("allow_duplicate_users", allow_duplicate_users, BOOL), CONFIG("kill_timedout_sessions", kill_timedout_sessions, BOOL), CONFIG("guest_account", guest_user, STRING), CONFIG("bind_address", bind_address, IPv4), CONFIG("peer_address", peer_address, IPv4), CONFIG("send_garp", send_garp, BOOL), CONFIG("throttle_speed", rl_rate, UNSIGNED_LONG), CONFIG("throttle_buckets", num_tbfs, INT), CONFIG("accounting_dir", accounting_dir, STRING), CONFIG("account_all_origin", account_all_origin, BOOL), 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_port", cluster_port, INT), 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), CONFIG("cli_bind_address", cli_bind_address, IPv4), CONFIG("hostname", hostname, STRING), #ifdef BGP CONFIG("nexthop_address", nexthop_address, IPv4), CONFIG("nexthop6_address", nexthop6_address, IPv6), #endif CONFIG("echo_timeout", echo_timeout, INT), CONFIG("idle_echo_timeout", idle_echo_timeout, INT), CONFIG("iftun_address", iftun_address, IPv4), CONFIG("tundevicename", tundevicename, STRING), CONFIG("disable_lac_func", disable_lac_func, BOOL), CONFIG("auth_tunnel_change_addr_src", auth_tunnel_change_addr_src, BOOL), CONFIG("bind_address_remotelns", bind_address_remotelns, IPv4), CONFIG("bind_portremotelns", bind_portremotelns, SHORT), CONFIG("pppoe_if_to_bind", pppoe_if_to_bind, STRING), CONFIG("pppoe_service_name", pppoe_service_name, STRING), CONFIG("pppoe_ac_name", pppoe_ac_name, STRING), CONFIG("disable_sending_hello", disable_sending_hello, BOOL), CONFIG("disable_no_spoof", disable_no_spoof, BOOL), CONFIG("bind_multi_address", bind_multi_address, STRING), CONFIG("pppoe_only_equal_svc_name", pppoe_only_equal_svc_name, BOOL), CONFIG("multi_hostname", multi_hostname, STRING), CONFIG("no_throttle_local_IP", no_throttle_local_IP, BOOL), CONFIG("dhcp6_preferred_lifetime", dhcp6_preferred_lifetime, INT), CONFIG("dhcp6_valid_lifetime", dhcp6_valid_lifetime, INT), CONFIG("dhcp6_server_duid", dhcp6_server_duid, INT), CONFIG("dns6_lifetime", dns6_lifetime, INT), CONFIG("primary_ipv6_dns", default_ipv6_dns1, IPv6), CONFIG("secondary_ipv6_dns", default_ipv6_dns2, IPv6), CONFIG("default_ipv6_domain_list", default_ipv6_domain_list, STRING), { NULL, 0, 0, 0 } }; static char *plugin_functions[] = { NULL, "plugin_pre_auth", "plugin_post_auth", "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. bundlet *bundle = NULL; // Array of bundle structures. fragmentationt *frag = NULL; // Array of fragmentation 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 ssize_t netlink_send(struct nlmsghdr *nh); static void netlink_addattr(struct nlmsghdr *nh, int type, const void *data, int alen); static void cache_ipmap(in_addr_t ip, sessionidt s); static void uncache_ipmap(in_addr_t ip); static void cache_ipv6map(struct in6_addr ip, int prefixlen, sessionidt 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); static void bundleclear(bundleidt b); // 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++; } // Time in milliseconds // TODO FOR MLPPP DEV //time_now_ms = (t.tv_sec * 1000) + (t.tv_usec/1000); 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, MAX_LOG_LENGTH, 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' must be in _host_ order. // static void routeset(sessionidt s, in_addr_t ip, int prefixlen, in_addr_t gw, int add) { struct { struct nlmsghdr nh; struct rtmsg rt; char buf[32]; } req; int i; in_addr_t n_ip; if (!prefixlen) prefixlen = 32; ip &= 0xffffffff << (32 - prefixlen);; // Force the ip to be the first one in the route. memset(&req, 0, sizeof(req)); if (add) { req.nh.nlmsg_type = RTM_NEWROUTE; req.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE | NLM_F_REPLACE; } else { req.nh.nlmsg_type = RTM_DELROUTE; req.nh.nlmsg_flags = NLM_F_REQUEST; } req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(req.rt)); req.rt.rtm_family = AF_INET; req.rt.rtm_dst_len = prefixlen; req.rt.rtm_table = RT_TABLE_MAIN; req.rt.rtm_protocol = 42; req.rt.rtm_scope = RT_SCOPE_LINK; req.rt.rtm_type = RTN_UNICAST; netlink_addattr(&req.nh, RTA_OIF, &tunidx, sizeof(int)); n_ip = htonl(ip); netlink_addattr(&req.nh, RTA_DST, &n_ip, sizeof(n_ip)); if (gw) { n_ip = htonl(gw); netlink_addattr(&req.nh, RTA_GATEWAY, &n_ip, sizeof(n_ip)); } LOG(1, s, session[s].tunnel, "Route %s %s/%d%s%s\n", add ? "add" : "del", fmtaddr(htonl(ip), 0), prefixlen, gw ? " via" : "", gw ? fmtaddr(htonl(gw), 2) : ""); if (netlink_send(&req.nh) < 0) LOG(0, 0, 0, "routeset() error in sending netlink message: %s\n", strerror(errno)); #ifdef BGP if (add) bgp_add_route(htonl(ip), prefixlen); else bgp_del_route(htonl(ip), prefixlen); #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 < ip+(1<<(32-prefixlen)) ; ++i) cache_ipmap(i, s); } } void route6set(sessionidt s, struct in6_addr ip, int prefixlen, int add) { struct { struct nlmsghdr nh; struct rtmsg rt; char buf[64]; } req; int metric; char ipv6addr[INET6_ADDRSTRLEN]; if (!config->ipv6_prefix.s6_addr[0]) { LOG(0, 0, 0, "Asked to set IPv6 route, but IPv6 not setup.\n"); return; } memset(&req, 0, sizeof(req)); if (add) { req.nh.nlmsg_type = RTM_NEWROUTE; req.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE | NLM_F_REPLACE; } else { req.nh.nlmsg_type = RTM_DELROUTE; req.nh.nlmsg_flags = NLM_F_REQUEST; } req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(req.rt)); req.rt.rtm_family = AF_INET6; req.rt.rtm_dst_len = prefixlen; req.rt.rtm_table = RT_TABLE_MAIN; req.rt.rtm_protocol = 42; req.rt.rtm_scope = RT_SCOPE_LINK; req.rt.rtm_type = RTN_UNICAST; netlink_addattr(&req.nh, RTA_OIF, &tunidx, sizeof(int)); netlink_addattr(&req.nh, RTA_DST, &ip, sizeof(ip)); metric = 1; netlink_addattr(&req.nh, RTA_METRICS, &metric, sizeof(metric)); LOG(1, s, session[s].tunnel, "Route %s %s/%d\n", add ? "add" : "del", inet_ntop(AF_INET6, &ip, ipv6addr, INET6_ADDRSTRLEN), prefixlen); if (netlink_send(&req.nh) < 0) LOG(0, 0, 0, "route6set() error in sending netlink message: %s\n", strerror(errno)); #ifdef BGP if (add) bgp_add_route6(ip, prefixlen); else bgp_del_route6(ip, prefixlen); #endif /* BGP */ 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; } // // Set up netlink socket static void initnetlink(void) { struct sockaddr_nl nladdr; nlfd = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE); if (nlfd < 0) { LOG(0, 0, 0, "Can't create netlink socket: %s\n", strerror(errno)); exit(1); } memset(&nladdr, 0, sizeof(nladdr)); nladdr.nl_family = AF_NETLINK; nladdr.nl_pid = getpid(); if (bind(nlfd, (struct sockaddr *)&nladdr, sizeof(nladdr)) < 0) { LOG(0, 0, 0, "Can't bind netlink socket: %s\n", strerror(errno)); exit(1); } } static ssize_t netlink_send(struct nlmsghdr *nh) { struct sockaddr_nl nladdr; struct iovec iov; struct msghdr msg; nh->nlmsg_pid = getpid(); nh->nlmsg_seq = ++nlseqnum; // set kernel address memset(&nladdr, 0, sizeof(nladdr)); nladdr.nl_family = AF_NETLINK; iov = (struct iovec){ (void *)nh, nh->nlmsg_len }; msg = (struct msghdr){ (void *)&nladdr, sizeof(nladdr), &iov, 1, NULL, 0, 0 }; return sendmsg(nlfd, &msg, 0); } static ssize_t netlink_recv(void *buf, ssize_t len) { struct sockaddr_nl nladdr; struct iovec iov; struct msghdr msg; // set kernel address memset(&nladdr, 0, sizeof(nladdr)); nladdr.nl_family = AF_NETLINK; iov = (struct iovec){ buf, len }; msg = (struct msghdr){ (void *)&nladdr, sizeof(nladdr), &iov, 1, NULL, 0, 0 }; return recvmsg(nlfd, &msg, 0); } /* adapted from iproute2 */ static void netlink_addattr(struct nlmsghdr *nh, int type, const void *data, int alen) { int len = RTA_LENGTH(alen); struct rtattr *rta; rta = (struct rtattr *)(((void *)nh) + NLMSG_ALIGN(nh->nlmsg_len)); rta->rta_type = type; rta->rta_len = len; memcpy(RTA_DATA(rta), data, alen); nh->nlmsg_len = NLMSG_ALIGN(nh->nlmsg_len) + RTA_ALIGN(len); } // messages corresponding to different phases seq number static char *tun_nl_phase_msg[] = { "initialized", "getting tun interface index", "setting tun interface parameters", "setting tun IPv4 address", "setting tun LL IPv6 address", "setting tun global IPv6 address", }; // // Set up TUN interface static void inittun(void) { struct ifreq ifr; 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 (*config->tundevicename) strncpy(ifr.ifr_name, config->tundevicename, IFNAMSIZ); 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->tundevicename) - 1); strncpy(config->tundevicename, ifr.ifr_name, sizeof(config->tundevicename)); tunidx = if_nametoindex(config->tundevicename); if (tunidx == 0) { LOG(0, 0, 0, "Can't get tun interface index\n"); exit(1); } { struct { // interface setting struct nlmsghdr nh; union { struct ifinfomsg ifinfo; struct ifaddrmsg ifaddr; } ifmsg; char rtdata[32]; // 32 should be enough } req; uint32_t txqlen, mtu; in_addr_t ip; memset(&req, 0, sizeof(req)); req.nh.nlmsg_type = RTM_NEWLINK; req.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_MULTI; req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(req.ifmsg.ifinfo)); req.ifmsg.ifinfo.ifi_family = AF_UNSPEC; req.ifmsg.ifinfo.ifi_index = tunidx; req.ifmsg.ifinfo.ifi_flags |= IFF_UP; // set interface up req.ifmsg.ifinfo.ifi_change = IFF_UP; // only change this flag /* Bump up the qlen to deal with bursts from the network */ txqlen = 1000; netlink_addattr(&req.nh, IFLA_TXQLEN, &txqlen, sizeof(txqlen)); /* set MTU to modem MRU */ mtu = MRU; netlink_addattr(&req.nh, IFLA_MTU, &mtu, sizeof(mtu)); if (netlink_send(&req.nh) < 0) goto senderror; memset(&req, 0, sizeof(req)); req.nh.nlmsg_type = RTM_NEWADDR; req.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE | NLM_F_REPLACE | NLM_F_MULTI; req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(req.ifmsg.ifaddr)); req.ifmsg.ifaddr.ifa_family = AF_INET; req.ifmsg.ifaddr.ifa_prefixlen = 32; req.ifmsg.ifaddr.ifa_scope = RT_SCOPE_UNIVERSE; req.ifmsg.ifaddr.ifa_index = tunidx; if (config->nbmultiaddress > 1) { int i; for (i = 0; i < config->nbmultiaddress ; i++) { ip = config->iftun_n_address[i]; netlink_addattr(&req.nh, IFA_LOCAL, &ip, sizeof(ip)); if (netlink_send(&req.nh) < 0) goto senderror; } } else { if (config->iftun_address) ip = config->iftun_address; else ip = 0x01010101; // 1.1.1.1 netlink_addattr(&req.nh, IFA_LOCAL, &ip, sizeof(ip)); if (netlink_send(&req.nh) < 0) goto senderror; } // Only setup IPv6 on the tun device if we have a configured prefix if (config->ipv6_prefix.s6_addr[0]) { struct in6_addr ip6; memset(&req, 0, sizeof(req)); req.nh.nlmsg_type = RTM_NEWADDR; req.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE | NLM_F_REPLACE | NLM_F_MULTI; req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(req.ifmsg.ifaddr)); req.ifmsg.ifaddr.ifa_family = AF_INET6; req.ifmsg.ifaddr.ifa_prefixlen = 64; req.ifmsg.ifaddr.ifa_scope = RT_SCOPE_LINK; req.ifmsg.ifaddr.ifa_index = tunidx; // Link local address is FE80::1 memset(&ip6, 0, sizeof(ip6)); ip6.s6_addr[0] = 0xFE; ip6.s6_addr[1] = 0x80; ip6.s6_addr[15] = 1; netlink_addattr(&req.nh, IFA_LOCAL, &ip6, sizeof(ip6)); if (netlink_send(&req.nh) < 0) goto senderror; memset(&req, 0, sizeof(req)); req.nh.nlmsg_type = RTM_NEWADDR; req.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE | NLM_F_REPLACE | NLM_F_MULTI; req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(req.ifmsg.ifaddr)); req.ifmsg.ifaddr.ifa_family = AF_INET6; req.ifmsg.ifaddr.ifa_prefixlen = 64; req.ifmsg.ifaddr.ifa_scope = RT_SCOPE_UNIVERSE; req.ifmsg.ifaddr.ifa_index = tunidx; // Global address is prefix::1 ip6 = config->ipv6_prefix; ip6.s6_addr[15] = 1; netlink_addattr(&req.nh, IFA_LOCAL, &ip6, sizeof(ip6)); if (netlink_send(&req.nh) < 0) goto senderror; } memset(&req, 0, sizeof(req)); req.nh.nlmsg_type = NLMSG_DONE; req.nh.nlmsg_len = NLMSG_LENGTH(0); if (netlink_send(&req.nh) < 0) goto senderror; // if we get an error for seqnum < min_initok_nlseqnum, // we must exit as initialization went wrong if (config->ipv6_prefix.s6_addr[0]) min_initok_nlseqnum = 5 + 1; // idx + if + addr + 2*addr6 else min_initok_nlseqnum = 3 + 1; // idx + if + addr } return; senderror: LOG(0, 0, 0, "Error while setting up tun device: %s\n", strerror(errno)); exit(1); } // set up LAC UDP ports static void initlacudp(void) { int on = 1; struct sockaddr_in addr; // Tunnel to Remote LNS memset(&addr, 0, sizeof(addr)); addr.sin_family = AF_INET; addr.sin_port = htons(config->bind_portremotelns); addr.sin_addr.s_addr = config->bind_address_remotelns; udplacfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP); setsockopt(udplacfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)); { int flags = fcntl(udplacfd, F_GETFL, 0); fcntl(udplacfd, F_SETFL, flags | O_NONBLOCK); } if (bind(udplacfd, (struct sockaddr *) &addr, sizeof(addr)) < 0) { LOG(0, 0, 0, "Error in UDP REMOTE LNS bind: %s\n", strerror(errno)); exit(1); } } // set up control ports static void initcontrol(void) { int on = 1; struct sockaddr_in addr; // 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, (struct sockaddr *) &addr, sizeof(addr)) < 0) { LOG(0, 0, 0, "Error in control bind: %s\n", strerror(errno)); exit(1); } } // set up Dynamic Authorization Extensions to RADIUS port static void initdae(void) { int on = 1; struct sockaddr_in addr; // 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, (struct sockaddr *) &addr, sizeof(addr)) < 0) { LOG(0, 0, 0, "Error in DAE bind: %s\n", strerror(errno)); exit(1); } } // set up UDP ports static void initudp(int * pudpfd, in_addr_t ip_bind) { 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 = ip_bind; (*pudpfd) = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP); setsockopt((*pudpfd), SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)); { int flags = fcntl((*pudpfd), F_GETFL, 0); fcntl((*pudpfd), F_SETFL, flags | O_NONBLOCK); } if (bind((*pudpfd), (struct sockaddr *) &addr, sizeof(addr)) < 0) { LOG(0, 0, 0, "Error in UDP bind: %s\n", strerror(errno)); exit(1); } } // // 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 sessionidt lookup_ipmap(in_addr_t ip) { uint8_t *a = (uint8_t *) &ip; union iphash *h = ip_hash; if (!(h = h[*a++].idx)) return 0; if (!(h = h[*a++].idx)) return 0; if (!(h = h[*a++].idx)) return 0; return h[*a].sess; } static sessionidt lookup_ipv6map(struct in6_addr ip) { struct ipv6radix *curnode; int i; int s; char ipv6addr[INET6_ADDRSTRLEN]; curnode = &ipv6_hash[((ip.s6_addr[0]) & 0xF0)>>4]; i = 1; s = curnode->sess; while (s == 0 && i < 32 && curnode->branch != NULL) { if (i & 1) curnode = &curnode->branch[ip.s6_addr[i>>1] & 0x0F]; else curnode = &curnode->branch[(ip.s6_addr[i>>1] & 0xF0)>>4]; 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) { sessionidt s = lookup_ipmap(ip); CSTAT(sessionbyip); if (s > 0 && s < MAXSESSION && session[s].opened) return s; return 0; } sessionidt sessionbyipv6(struct in6_addr ip) { sessionidt 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)) { in_addr_t *pipv4 = (in_addr_t *) &ip.s6_addr[8]; s = lookup_ipmap(*pipv4); } else { s = lookup_ipv6map(ip); } if (s > 0 && s < MAXSESSION && session[s].opened) return s; return 0; } sessionidt sessionbyipv6new(struct in6_addr ip) { sessionidt s; CSTAT(sessionbyipv6new); 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, sessionidt 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; union iphash *h = ip_hash; int i; for (i = 0; i < 3; i++) { if (!(h[a[i]].idx || (h[a[i]].idx = calloc(256, sizeof(union iphash))))) return; h = h[a[i]].idx; } h[a[3]].sess = 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, sessionidt s) { int i; int niblles; struct ipv6radix *curnode; char ipv6addr[INET6_ADDRSTRLEN]; curnode = &ipv6_hash[((ip.s6_addr[0]) & 0xF0)>>4]; niblles = prefixlen >> 2; i = 1; while (i < niblles) { if (curnode->branch == NULL) { if (!(curnode->branch = calloc(16, sizeof (struct ipv6radix)))) return; } if (i & 1) curnode = &curnode->branch[ip.s6_addr[i>>1] & 0x0F]; else curnode = &curnode->branch[(ip.s6_addr[i>>1] & 0xF0)>>4]; 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, const char *command, char **argv, int argc) { union iphash *d = 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].idx) continue; e = d[i].idx; for (j = 0; j < 256; ++j) { if (!e[j].idx) continue; f = e[j].idx; for (k = 0; k < 256; ++k) { if (!f[k].idx) continue; g = f[k].idx; for (l = 0; l < 256; ++l) { if (!g[l].sess) continue; cli_print(cli, "%7d %d.%d.%d.%d", g[l].sess, 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 (t == TUNNEL_ID_PPPOE) { pppoe_sess_send(buf, l, t); 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[tunnel[t].indexudp], 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[tunnel[t].indexudp], 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)); } void processmpframe(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l, uint8_t extra) { uint16_t proto; if (extra) { // Skip the four extra bytes p += 4; l -= 4; } if (*p & 1) { proto = *p++; l--; } else { proto = ntohs(*(uint16_t *) p); p += 2; l -= 2; } if (proto == PPPIP) { if (session[s].die) { LOG(4, s, t, "MPPP: Session %d is closing. Don't process PPP packets\n", s); return; // closing session, PPP not processed } session[s].last_packet = session[s].last_data = time_now; processipin(s, t, p, l); } else if (proto == PPPIPV6 && config->ipv6_prefix.s6_addr[0]) { if (session[s].die) { LOG(4, s, t, "MPPP: Session %d is closing. Don't process PPP packets\n", s); return; // closing session, PPP not processed } session[s].last_packet = session[s].last_data = time_now; processipv6in(s, t, p, l); } else if (proto == PPPIPCP) { session[s].last_packet = session[s].last_data = time_now; processipcp(s, t, p, l); } else if (proto == PPPCCP) { session[s].last_packet = session[s].last_data = time_now; processccp(s, t, p, l); } else { LOG(2, s, t, "MPPP: Unsupported MP protocol 0x%04X received\n",proto); } } static void update_session_out_stat(sessionidt s, sessiont *sp, int len) { increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count sp->cout_delta += len; sp->pout++; sp->last_data = time_now; sess_local[s].cout += len; // To send to master.. sess_local[s].pout++; } // process outgoing (to tunnel) IP // // (i.e. this routine writes to data[-8]). void processipout(uint8_t *buf, int len) { sessionidt s; sessiont *sp; tunnelidt t; in_addr_t ip, ip_src; uint8_t *data = buf; // Keep a copy of the originals. int size = len; uint8_t fragbuf[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_src = *(uint32_t *)(buf + 12); 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; if (len > session[s].mru || (session[s].mrru && len > session[s].mrru)) { LOG(3, s, t, "Packet size more than session MRU\n"); return; } 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) { if (!config->no_throttle_local_IP || !sessionbyip(ip_src)) { // 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; } if(session[s].bundle != 0 && bundle[session[s].bundle].num_of_links > 1) { if (!config->cluster_iam_master) { // The MPPP packets must be managed by the Master. master_forward_mppp_packet(s, data, size); return; } // Add on L2TP header sessionidt members[MAXBUNDLESES]; bundleidt bid = session[s].bundle; bundlet *b = &bundle[bid]; uint32_t num_of_links, nb_opened; int i; num_of_links = b->num_of_links; nb_opened = 0; for (i = 0;i < num_of_links;i++) { s = b->members[i]; if (session[s].ppp.lcp == Opened) { members[nb_opened] = s; nb_opened++; } } if (nb_opened < 1) { LOG(3, s, t, "MPPP: PROCESSIPOUT ERROR, no session opened in bundle:%d\n", bid); return; } num_of_links = nb_opened; b->current_ses = (b->current_ses + 1) % num_of_links; s = members[b->current_ses]; t = session[s].tunnel; sp = &session[s]; LOG(4, s, t, "MPPP: (1)Session number becomes: %d\n", s); if (num_of_links > 1) { if(len > MINFRAGLEN) { //for rotate traffic among the member links uint32_t divisor = num_of_links; if (divisor > 2) divisor = divisor/2 + (divisor & 1); // Partition the packet to "num_of_links" fragments uint32_t fraglen = len / divisor; uint32_t last_fraglen = fraglen + len % divisor; uint32_t remain = len; // send the first packet uint8_t *p = makeppp(fragbuf, sizeof(fragbuf), buf, fraglen, s, t, PPPIP, 0, bid, MP_BEGIN); if (!p) return; tunnelsend(fragbuf, fraglen + (p-fragbuf), t); // send it... // statistics update_session_out_stat(s, sp, fraglen); remain -= fraglen; while (remain > last_fraglen) { b->current_ses = (b->current_ses + 1) % num_of_links; s = members[b->current_ses]; t = session[s].tunnel; sp = &session[s]; LOG(4, s, t, "MPPP: (2)Session number becomes: %d\n", s); p = makeppp(fragbuf, sizeof(fragbuf), buf+(len - remain), fraglen, s, t, PPPIP, 0, bid, 0); if (!p) return; tunnelsend(fragbuf, fraglen + (p-fragbuf), t); // send it... update_session_out_stat(s, sp, fraglen); remain -= fraglen; } // send the last fragment b->current_ses = (b->current_ses + 1) % num_of_links; s = members[b->current_ses]; t = session[s].tunnel; sp = &session[s]; LOG(4, s, t, "MPPP: (2)Session number becomes: %d\n", s); p = makeppp(fragbuf, sizeof(fragbuf), buf+(len - remain), remain, s, t, PPPIP, 0, bid, MP_END); if (!p) return; tunnelsend(fragbuf, remain + (p-fragbuf), t); // send it... update_session_out_stat(s, sp, remain); if (remain != last_fraglen) LOG(3, s, t, "PROCESSIPOUT ERROR REMAIN != LAST_FRAGLEN, %d != %d\n", remain, last_fraglen); } else { // Send it as one frame uint8_t *p = makeppp(fragbuf, sizeof(fragbuf), buf, len, s, t, PPPIP, 0, bid, MP_BOTH_BITS); if (!p) return; tunnelsend(fragbuf, len + (p-fragbuf), t); // send it... LOG(4, s, t, "MPPP: packet sent as one frame\n"); update_session_out_stat(s, sp, len); } } else { // Send it as one frame (NO MPPP Frame) uint8_t *p = opt_makeppp(buf, len, s, t, PPPIP, 0, 0, 0); tunnelsend(p, len + (buf-p), t); // send it... update_session_out_stat(s, sp, len); } } else { uint8_t *p = opt_makeppp(buf, len, s, t, PPPIP, 0, 0, 0); tunnelsend(p, len + (buf-p), t); // send it... update_session_out_stat(s, sp, len); } // 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); udp_tx += len; } // process outgoing (to tunnel) IPv6 // static void processipv6out(uint8_t * buf, int len) { sessionidt s; sessiont *sp; tunnelidt t; 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) { s = sessionbyipv6new(ip6); } if (s == 0) { // Is this a packet for a session that doesn't exist? static int rate = 0; // Number of ICMP packets we've sent this second. static int last = 0; // Last time we reset the ICMP packet counter 'rate'. if (last != time_now) { last = time_now; rate = 0; } if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second. { // FIXME: Should send icmp6 host unreachable } return; } if (session[s].bundle && bundle[session[s].bundle].num_of_links > 1) { bundleidt bid = session[s].bundle; bundlet *b = &bundle[bid]; b->current_ses = (b->current_ses + 1) % b->num_of_links; s = b->members[b->current_ses]; LOG(3, s, session[s].tunnel, "MPPP: Session number becomes: %u\n", s); } t = session[s].tunnel; sp = &session[s]; sp->last_data = time_now; // 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, 0, 0, 0); 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; uint8_t *p; uint8_t *data = buf; // Keep a copy of the originals. 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; 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 if (*(uint16_t *) (data + 2) == htons(PKTIPV6)) p = makeppp(b, sizeof(b), buf, len, s, t, PPPIPV6, 0, 0, 0); // IPV6 else p = makeppp(b, sizeof(b), buf, len, s, t, PPPIP, 0, 0, 0); // IPV4 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 *pint16 = (uint16_t *) (c->buf + c->length + 0); pint16[0] = htons(l); pint16[1] = htons(0); pint16[2] = htons(avp); pint16[3] = 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 *pint16 = (uint16_t *) (c->buf + c->length + 0); uint32_t *pint32 = (uint32_t *) (c->buf + c->length + 6); pint16[0] = htons(l); pint16[1] = htons(0); pint16[2] = htons(avp); pint32[0] = 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 *pint16 = (uint16_t *) (c->buf + c->length + 0); pint16[0] = htons(l); pint16[1] = htons(0); pint16[2] = 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 *pint16 = (uint16_t *) (c->buf + c->length + 0); pint16[0] = htons(l); pint16[1] = htons(0); pint16[2] = 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; c->buf[0] = 0xC8; // flags c->buf[1] = 0x02; // 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) { uint16_t buf[6]; if (tunnel[t].controlc) // Messages queued; They will carry the ack. return; buf[0] = htons(0xC802); // flags/ver buf[1] = htons(12); // length buf[2] = htons(tunnel[t].far); // tunnel buf[3] = htons(0); // session buf[4] = htons(tunnel[t].ns); // sequence buf[5] = htons(tunnel[t].nr); // sequence tunnelsend((uint8_t *)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 *pint16 = (uint16_t *) (c->buf + 2); pint16[0] = htons(c->length); // length pint16[1] = htons(tunnel[t].far); // tunnel pint16[2] = htons(far); // session pint16[3] = 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; bundleidt b = session[s].bundle; //delete routes only for last session in bundle (in case of MPPP) int del_routes = !b || (bundle[b].num_of_links == 1); 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 %u: %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].die) session[s].die = TIME + 150; // Clean up in 15 seconds 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 >> (32-session[s].route[r].prefixlen)) == (session[s].route[r].ip >> (32-session[s].route[r].prefixlen))) routed++; if (del_routes) routeset(s, session[s].route[r].ip, session[s].route[r].prefixlen, 0, 0); session[s].route[r].ip = 0; } if (session[s].ip_pool_index == -1) // static ip { if (!routed && del_routes) routeset(s, session[s].ip, 0, 0, 0); session[s].ip = 0; } else free_ip_address(s); // unroute IPv6, if setup for (r = 0; r < MAXROUTE6 && session[s].route6[r].ipv6route.s6_addr[0] && session[s].route6[r].ipv6prefixlen; r++) { if (del_routes) route6set(s, session[s].route6[r].ipv6route, session[s].route6[r].ipv6prefixlen, 0); memset(&session[s].route6[r], 0, sizeof(session[s].route6[r])); } if (session[s].ipv6address.s6_addr[0] && del_routes) { route6set(s, session[s].ipv6address, 128, 0); } if (b) { // This session was part of a bundle bundle[b].num_of_links--; LOG(3, s, session[s].tunnel, "MPPP: Dropping member link: %d from bundle %d\n",s,b); if(bundle[b].num_of_links == 0) { bundleclear(b); LOG(3, s, session[s].tunnel, "MPPP: Kill bundle: %d (No remaing member links)\n",b); } else { // Adjust the members array to accomodate the new change uint8_t mem_num = 0; // It should be here num_of_links instead of num_of_links-1 (previous instruction "num_of_links--") if(bundle[b].members[bundle[b].num_of_links] != s) { uint8_t ml; for(ml = 0; mlpeer_address ? config->peer_address : config->iftun_n_address[tunnel[t].indexudp] ? config->iftun_n_address[tunnel[t].indexudp] : 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, 0, 0, 0); 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 (%u)\n", session[s].next); return; } if (!session[s].die) 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 if (session[s].forwardtosession) { sessionidt sess = session[s].forwardtosession; if (session[sess].forwardtosession == s) { // Shutdown the linked session also. sessionshutdown(sess, reason, CDN_ADMIN_DISC, TERM_ADMIN_RESET); } } 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; } static void bundleclear(bundleidt b) { if (!b) return; memset(&bundle[b], 0, sizeof(bundle[b])); bundle[b].state = BUNDLEFREE; } // kill a tunnel now static void tunnelkill(tunnelidt t, char *reason) { 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 %u: %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 %u (%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) { uint16_t buf[32]; int l = 4; buf[0] = htons(result); buf[1] = htons(error); if (msg) { int m = strlen(msg); if (m + 4 > sizeof(buf)) m = sizeof(buf) - 4; memcpy(buf+2, msg, m); l += m; } controlb(c, 1, (uint8_t *)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, uint16_t indexudpfd) { uint8_t *sendchalresponse = NULL; uint8_t *recvchalresponse = 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); 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 (t == TUNNEL_ID_PPPOE) { LOG(1, s, t, "Received UDP packet with tunnel ID reserved for pppoe\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, indexudpfd); 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 %u l-nr %u r-ns %u r-nr %u\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 tunnel[t].indexudp = indexudpfd; STAT(tunnel_created); LOG(1, 0, t, " New tunnel from %s:%u ID %u\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 %u, (%u is not the expected %u)\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; if (n == 0) { // if continue a infinity loop is created. LOG(1, s, t, "It's infinite loop protection %02X\n", *b); return; } else continue; // next } b += 2; if (*(uint16_t *) (b)) { LOG(2, s, t, "Unknown AVP vendor %u\n", ntohs(*(uint16_t *) (b))); fatal = flags; result = 2; // general error error = 6; // generic vendor-specific error msg = "unsupported vendor-specific"; if (n == 0) { // if continue a infinity loop is created. LOG(1, s, t, "It's infinite loop protection %02X\n", *b); return; } else 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(3, s, t, " AVP %u (%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(3, s, t, " Message type = %u (%s)\n", message, 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(3, s, t, " Result Code %u: %s\n", rescode, resdesc); if (n >= 4) { uint16_t errcode = ntohs(*(uint16_t *)(b + 2)); errdesc = l2tp_error_code(errcode); LOG(3, s, t, " Error Code %u: %s\n", errcode, errdesc); } if (n > 4) LOG(3, 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(3, s, t, " Protocol version = %u\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(3, 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(3, s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor); break; case 9: // assigned tunnel tunnel[t].far = ntohs(*(uint16_t *) (b)); LOG(3, s, t, " Remote tunnel id = %u\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(3, s, t, " rx window = %u\n", tunnel[t].window); break; case 11: // Request Challenge { LOG(3, s, t, " LAC requested CHAP authentication for tunnel\n"); if (message == 1) build_chap_response(b, 2, n, &sendchalresponse); else if (message == 2) build_chap_response(b, 3, n, &sendchalresponse); } break; case 13: // receive challenge Response if (tunnel[t].isremotelns) { recvchalresponse = calloc(17, 1); memcpy(recvchalresponse, b, (n < 17) ? n : 16); LOG(3, s, t, "received challenge response from REMOTE LNS\n"); } else // 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(3, s, t, " assigned session = %u\n", asession); break; case 15: // call serial number LOG(3, s, t, " call serial number = %u\n", ntohl(*(uint32_t *)b)); break; case 18: // bearer type LOG(3, s, t, " bearer type = %u\n", ntohl(*(uint32_t *)b)); // TBA - for RADIUS break; case 19: // framing type LOG(3, s, t, " framing type = %u\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(3, 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(3, 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(3, 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(3, 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(3, s, t, " Physical Channel ID <%X>\n", tmp); break; } case 29: // Proxy Authentication Type { uint16_t atype = ntohs(*(uint16_t *)b); LOG(3, s, t, " Proxy Auth Type %u (%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(3, s, t, " Proxy Auth Name (%s)\n", authname); break; } case 31: // Proxy Authentication Challenge { LOG(3, s, t, " Proxy Auth Challenge\n"); break; } case 32: // Proxy Authentication ID { uint16_t authid = ntohs(*(uint16_t *)(b)); LOG(3, s, t, " Proxy Auth ID (%u)\n", authid); break; } case 33: // Proxy Authentication Response LOG(3, 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(3, 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(3, 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 %u\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; LOG(3, s, t, "Received SCCRQ\n"); if (main_quit != QUIT_SHUTDOWN) { LOG(3, s, t, "sending SCCRP\n"); controlt *c = controlnew(2); // sending SCCRP control16(c, 2, version, 1); // protocol version control32(c, 3, 3, 1); // framing controls(c, 7, config->multi_n_hostname[tunnel[t].indexudp][0]?config->multi_n_hostname[tunnel[t].indexudp]:hostname, 1); // host name if (sendchalresponse) controlb(c, 13, sendchalresponse, 16, 1); // Send 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; tunnel[t].lastrec = time_now; LOG(3, s, t, "Received SCCRP\n"); if (main_quit != QUIT_SHUTDOWN) { if (tunnel[t].isremotelns && recvchalresponse) { hasht hash; lac_calc_rlns_auth(t, 2, hash); // id = 2 (SCCRP) // check authenticator if (memcmp(hash, recvchalresponse, 16) == 0) { LOG(3, s, t, "sending SCCCN to REMOTE LNS\n"); controlt *c = controlnew(3); // sending SCCCN controls(c, 7, config->multi_n_hostname[tunnel[t].indexudp][0]?config->multi_n_hostname[tunnel[t].indexudp]:hostname, 1); // host name controls(c, 8, Vendor_name, 1); // Vendor name control16(c, 2, version, 1); // protocol version control32(c, 3, 3, 1); // framing Capabilities if (sendchalresponse) controlb(c, 13, sendchalresponse, 16, 1); // Challenge response control16(c, 9, t, 1); // assigned tunnel controladd(c, 0, t); // send } else { tunnelshutdown(t, "Bad chap response from REMOTE LNS", 4, 0, 0); } } } else { tunnelshutdown(t, "Shutting down", 6, 0, 0); } break; case 3: // SCCN LOG(3, s, t, "Received SCCN\n"); tunnel[t].state = TUNNELOPEN; tunnel[t].lastrec = time_now; controlnull(t); // ack break; case 4: // StopCCN LOG(3, s, t, "Received StopCCN\n"); controlnull(t); // ack tunnelshutdown(t, "Stopped", 0, 0, 0); // Shut down cleanly break; case 6: // HELLO LOG(3, s, t, "Received HELLO\n"); controlnull(t); // simply ACK break; case 7: // OCRQ // TBA LOG(3, s, t, "Received OCRQ\n"); break; case 8: // OCRO // TBA LOG(3, s, t, "Received OCRO\n"); break; case 9: // OCCN // TBA LOG(3, s, t, "Received OCCN\n"); break; case 10: // ICRQ LOG(3, s, t, "Received ICRQ\n"); if (sessionfree && main_quit != QUIT_SHUTDOWN) { controlt *c = controlnew(11); // ICRP LOG(3, s, t, "Sending ICRP\n"); 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 = session[s].last_data = time_now; LOG(3, s, t, "New session (%u/%u)\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 LOG(3, s, t, "Sending CDN\n"); 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 LOG(3, s, t, "Received ICRP\n"); if (session[s].forwardtosession) { controlt *c = controlnew(12); // ICCN session[s].opened = time_now; session[s].tunnel = t; session[s].far = asession; session[s].last_packet = session[s].last_data = time_now; control32(c, 19, 1, 1); // Framing Type control32(c, 24, 10000000, 1); // Tx Connect Speed controladd(c, asession, t); // send the message LOG(3, s, t, "Sending ICCN\n"); } break; case 12: // ICCN LOG(3, s, t, "Received ICCN\n"); 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; // Set multilink options before sending initial LCP packet sess_local[s].mp_mrru = 1614; sess_local[s].mp_epdis = ntohl(config->iftun_address ? config->iftun_address : my_address); sendlcp(s, t); change_state(s, lcp, RequestSent); break; case 14: // CDN LOG(3, s, t, "Received CDN\n"); 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 %u\n", message); break; } if (sendchalresponse) free(sendchalresponse); if (recvchalresponse) free(recvchalresponse); 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 (session[s].forwardtosession) { LOG(5, s, t, "Forwarding data session to session %u\n", session[s].forwardtosession); // Forward to LAC/BAS or Remote LNS session lac_session_forward(buf, len, s, proto, addr->sin_addr.s_addr, addr->sin_port, indexudpfd); return; } else if (config->auth_tunnel_change_addr_src) { if (tunnel[t].ip != ntohl(addr->sin_addr.s_addr) && tunnel[t].port == ntohs(addr->sin_port)) { // The remotes BAS are a clustered l2tpns server and the source IP has changed LOG(5, s, t, "The tunnel IP source (%s) has changed by new IP (%s)\n", fmtaddr(htonl(tunnel[t].ip), 0), fmtaddr(addr->sin_addr.s_addr, 0)); tunnel[t].ip = ntohl(addr->sin_addr.s_addr); } } 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, indexudpfd); 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, indexudpfd); 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, indexudpfd); 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, indexudpfd); 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, indexudpfd); 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, indexudpfd); 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, indexudpfd); return; } processccp(s, t, p, l); } else if (proto == PPPIP) { if (session[s].die) { LOG(4, s, t, "Session %u is closing. Don't process PPP packets\n", s); return; // closing session, PPP not processed } session[s].last_packet = session[s].last_data = time_now; if (session[s].walled_garden && !config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port, indexudpfd); return; } processipin(s, t, p, l); } else if (proto == PPPMP) { if (session[s].die) { LOG(4, s, t, "Session %u is closing. Don't process PPP packets\n", s); return; // closing session, PPP not processed } session[s].last_packet = session[s].last_data = time_now; if (!config->cluster_iam_master) { // The fragments reconstruction is managed by the Master. master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port, indexudpfd); return; } processmpin(s, t, p, l); } else if (proto == PPPIPV6 && config->ipv6_prefix.s6_addr[0]) { if (session[s].die) { LOG(4, s, t, "Session %u is closing. Don't process PPP packets\n", s); return; // closing session, PPP not processed } session[s].last_packet = session[s].last_data = time_now; if (session[s].walled_garden && !config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port, indexudpfd); return; } if (!config->cluster_iam_master) { // Check if DhcpV6, IP dst: FF02::1:2, Src Port 0x0222 (546), Dst Port 0x0223 (547) if (*(p + 6) == 17 && *(p + 24) == 0xFF && *(p + 25) == 2 && *(uint32_t *)(p + 26) == 0 && *(uint32_t *)(p + 30) == 0 && *(uint16_t *)(p + 34) == 0 && *(p + 36) == 0 && *(p + 37) == 1 && *(p + 38) == 0 && *(p + 39) == 2 && *(p + 40) == 2 && *(p + 41) == 0x22 && *(p + 42) == 2 && *(p + 43) == 0x23) { // DHCPV6 must be managed by the Master. master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port, indexudpfd); 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, indexudpfd); 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 // (i.e. this routine writes to buf[-8]). 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; if (t == TUNNEL_ID_PPPOE) continue; // 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; uint16_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) { if (!config->disable_sending_hello) { 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_ECHO_TIMEOUT seconds if (session[s].last_packet && (time_now - session[s].last_packet >= config->idle_echo_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 && ((!config->ppp_keepalive) || (time_now - session[s].last_packet >= config->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, 1, 0, 0); if (!q) continue; *q = EchoReq; *(uint8_t *)(q + 1) = (time_now % 255); // ID *(uint16_t *)(q + 2) = htons(8); // Length *(uint32_t *)(q + 4) = 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, (q - b) + 8, session[s].tunnel); // send it sess_local[s].last_echo = time_now; s_actions++; } // Drop sessions who have reached session_timeout seconds if (session[s].session_timeout) { bundleidt bid = session[s].bundle; if (bid) { if (time_now - bundle[bid].last_check >= 1) { bundle[bid].online_time += (time_now - bundle[bid].last_check) * bundle[bid].num_of_links; bundle[bid].last_check = time_now; if (bundle[bid].online_time >= session[s].session_timeout) { int ses; for (ses = bundle[bid].num_of_links - 1; ses >= 0; ses--) { sessionshutdown(bundle[bid].members[ses], "Session timeout", CDN_ADMIN_DISC, TERM_SESSION_TIMEOUT); s_actions++; continue; } } } } else if (time_now - session[s].opened >= session[s].session_timeout) { sessionshutdown(s, "Session timeout", CDN_ADMIN_DISC, TERM_SESSION_TIMEOUT); s_actions++; continue; } } // Drop sessions who have reached idle_timeout seconds if (session[s].last_data && session[s].idle_timeout && (time_now - session[s].last_data >= session[s].idle_timeout)) { sessionshutdown(s, "Idle Timeout Reached", CDN_ADMIN_DISC, TERM_IDLE_TIMEOUT); STAT(session_timeout); s_actions++; continue; } // 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:%u)\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 && session[s].flags & SESSION_STARTED) { 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; #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; if (!config->cluster_iam_master) { // we don't want to become master cluster_send_ping(0); return 1; } } if (!config->cluster_iam_master && time_now < (stopped_bgp + QUIT_DELAY)) return 1; } #endif /* BGP */ if (!config->cluster_iam_master) 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 %u 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 %u is still busy (sid %u)\n", i, radius[i].session); last_talked = TIME; } return 1; } return 0; } #ifdef HAVE_EPOLL # include #else # define FAKE_EPOLL_IMPLEMENTATION /* include the functions */ # include "fake_epoll.h" #endif // the base set of fds polled: cli, cluster, tun, udp (MAX_UDPFD), control, dae, netlink, udplac, pppoedisc, pppoesess #define BASE_FDS (9 + MAX_UDPFD) // 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, j; uint8_t buf[65536]; uint8_t *p = buf + 32; // for the hearder of the forwarded MPPP packet (see C_MPPP_FORWARD) // and the forwarded pppoe session int size_bufp = sizeof(buf) - 32; 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, nlfd=%d , udplacfd=%d, pppoefd=%d, pppoesessfd=%d\n", clifd, cluster_sockfd, tunfd, udpfd[0], controlfd, daefd, nlfd, udplacfd, pppoediscfd, pppoesessfd); /* setup our fds to poll for input */ { static struct event_data d[BASE_FDS]; struct epoll_event e; e.events = EPOLLIN; i = 0; if (clifd >= 0) { 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_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); d[i].type = FD_TYPE_NETLINK; e.data.ptr = &d[i++]; epoll_ctl(epollfd, EPOLL_CTL_ADD, nlfd, &e); d[i].type = FD_TYPE_PPPOEDISC; e.data.ptr = &d[i++]; epoll_ctl(epollfd, EPOLL_CTL_ADD, pppoediscfd, &e); d[i].type = FD_TYPE_PPPOESESS; e.data.ptr = &d[i++]; epoll_ctl(epollfd, EPOLL_CTL_ADD, pppoesessfd, &e); for (j = 0; j < config->nbudpfd; j++) { d[i].type = FD_TYPE_UDP; d[i].index = j; e.data.ptr = &d[i++]; epoll_ctl(epollfd, EPOLL_CTL_ADD, udpfd[j], &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, config->neighbour[i].update_source, 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[MAX_UDPFD + 1] = INIT_TABUDPVAR; int pppoesess_ready = 0; int pppoesess_pkts = 0; int tun_ready = 0; int cluster_ready = 0; int udp_pkts[MAX_UDPFD + 1] = INIT_TABUDPVAR; 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[d->index]++; break; case FD_TYPE_PPPOESESS: pppoesess_ready++; break; case FD_TYPE_PPPOEDISC: // pppoe discovery s = read(pppoediscfd, p, size_bufp); if (s > 0) process_pppoe_disc(p, s); n--; break; case FD_TYPE_CONTROL: // nsctl commands alen = sizeof(addr); s = recvfromto(controlfd, p, size_bufp, MSG_WAITALL, (struct sockaddr *) &addr, &alen, &local); if (s > 0) processcontrol(p, s, &addr, alen, &local); n--; break; case FD_TYPE_DAE: // DAE requests alen = sizeof(addr); s = recvfromto(daefd, p, size_bufp, MSG_WAITALL, (struct sockaddr *) &addr, &alen, &local); if (s > 0) processdae(p, s, &addr, alen, &local); n--; break; case FD_TYPE_RADIUS: // RADIUS response alen = sizeof(addr); s = recvfrom(radfds[d->index], p, size_bufp, 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(p, 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 */ case FD_TYPE_NETLINK: { struct nlmsghdr *nh = (struct nlmsghdr *)p; s = netlink_recv(p, size_bufp); if (nh->nlmsg_type == NLMSG_ERROR) { struct nlmsgerr *errmsg = NLMSG_DATA(nh); if (errmsg->error) { if (errmsg->msg.nlmsg_seq < min_initok_nlseqnum) { LOG(0, 0, 0, "Got a fatal netlink error (while %s): %s\n", tun_nl_phase_msg[nh->nlmsg_seq], strerror(-errmsg->error)); exit(1); } else LOG(0, 0, 0, "Got a netlink error: %s\n", strerror(-errmsg->error)); } // else it's a ack } else LOG(1, 0, 0, "Got a unknown netlink message: type %d seq %d flags %d\n", nh->nlmsg_type, nh->nlmsg_seq, nh->nlmsg_flags); n--; break; } 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++) { for (j = 0; j < config->nbudpfd; j++) { // L2TP and L2TP REMOTE LNS if (udp_ready[j]) { alen = sizeof(addr); if ((s = recvfrom(udpfd[j], p, size_bufp, 0, (void *) &addr, &alen)) > 0) { processudp(p, s, &addr, j); udp_pkts[j]++; } else { udp_ready[j] = 0; n--; } } } // incoming IP if (tun_ready) { if ((s = read(tunfd, p, size_bufp)) > 0) { processtun(p, s); tun_pkts++; } else { tun_ready = 0; n--; } } // pppoe session if (pppoesess_ready) { if ((s = read(pppoesessfd, p, size_bufp)) > 0) { process_pppoe_sess(p, s); pppoesess_pkts++; } else { pppoesess_ready = 0; n--; } } // cluster if (cluster_ready) { alen = sizeof(addr); if ((s = recvfrom(cluster_sockfd, p, size_bufp, MSG_WAITALL, (void *) &addr, &alen)) > 0) { processcluster(p, s, addr.sin_addr.s_addr); cluster_pkts++; } else { cluster_ready = 0; n--; } } } if (udp_pkts[0] > 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 %d cluster and %d pppoe packets\n", config->multi_read_count, udp_pkts[0], tun_pkts, cluster_pkts, pppoesess_pkts); STAT(multi_read_exceeded); more++; } } #ifdef BGP else /* no event received, but timers could still have expired */ bgp_process_peers_timers(); #endif /* BGP */ 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; config->kill_timedout_sessions = 1; strcpy(config->random_device, RANDOMDEVICE); // Set default value echo_timeout and idle_echo_timeout config->echo_timeout = ECHO_TIMEOUT; config->idle_echo_timeout = IDLE_ECHO_TIMEOUT; config->ppp_keepalive = 1; // Set default RDNSS lifetime config->dns6_lifetime = 1200; log_stream = stderr; #ifdef RINGBUFFER if (!(ringbuffer = shared_malloc(sizeof(struct Tringbuffer)))) { LOG(0, 0, 0, "Error doing malloc for ringbuffer: %s\n", strerror(errno)); exit(1); } memset(ringbuffer, 0, sizeof(struct Tringbuffer)); #endif if (!(_statistics = shared_malloc(sizeof(struct Tstats)))) { LOG(0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno)); exit(1); } if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL))) { LOG(0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno)); exit(1); } if (!(bundle = shared_malloc(sizeof(bundlet) * MAXBUNDLE))) { LOG(0, 0, 0, "Error doing malloc for bundles: %s\n", strerror(errno)); exit(1); } if (!(frag = shared_malloc(sizeof(fragmentationt) * MAXBUNDLE))) { LOG(0, 0, 0, "Error doing malloc for fragmentations: %s\n", strerror(errno)); exit(1); } if (!(session = shared_malloc(sizeof(sessiont) * MAXSESSION))) { LOG(0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno)); exit(1); } if (!(sess_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(bundle, 0, sizeof(bundlet) * MAXBUNDLE); memset(session, 0, sizeof(sessiont) * MAXSESSION); memset(radius, 0, sizeof(radiust) * MAXRADIUS); memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL); // Put all the sessions on the free list marked as undefined. for (i = 1; i < MAXSESSION; 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. for (i = 1; i < MAXBUNDLE; i++) { bundle[i].state = BUNDLEUNDEF; } 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 */ lac_initremotelnsdata(); } 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 %u 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 %u 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, int prefixlen) { int i; if (prefixlen == 0) prefixlen = 32; // Host route only. addr &= 0xffffffff << (32 - prefixlen); if (ip_pool_size >= MAXIPPOOL) // Pool is full! return ; for (i = addr ; i < addr+(1<<(32-prefixlen)); ++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; 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)); // Add a static route for this pool LOG(5, 0, 0, "Adding route for address pool %s/%d\n", fmtaddr(htonl(start), 0), numbits); routeset(0, start, numbits, 0, 1); add_to_ip_pool(start, numbits); } 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:%u\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->forwardtosession) || !(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); if(config->account_all_origin) { 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 origin(L=LAC, R=Remote LNS, P=PPPOE)\n", hostname, fmtaddr(config->iftun_n_address[tunnel[s->tunnel].indexudp] ? config->iftun_n_address[tunnel[s->tunnel].indexudp] : my_address, 0), now, now - basetime); } else { 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->iftun_n_address[tunnel[s->tunnel].indexudp] ? config->iftun_n_address[tunnel[s->tunnel].indexudp] : my_address, 0), now, now - basetime); } } LOG(4, 0, 0, "Dumping accounting information for %s\n", s->user); if(config->account_all_origin) { fprintf(*f, "%s %s %d %u %u %s\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->tunnel == TUNNEL_ID_PPPOE)?"P":(tunnel[s->tunnel].isremotelns?"R":"L")); // Origin } else if (!tunnel[s->tunnel].isremotelns && (s->tunnel != TUNNEL_ID_PPPOE)) { 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(); if(!freopen("/dev/null", "r", stdin)) LOG(0, 0, 0, "Error freopen stdin: %s\n", strerror(errno)); if(!freopen("/dev/null", "w", stdout)) LOG(0, 0, 0, "Error freopen stdout: %s\n", strerror(errno)); if(!freopen("/dev/null", "w", stderr)) LOG(0, 0, 0, "Error freopen stderr: %s\n", strerror(errno)); 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 \tConfig file\n" "\t-h \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(); read_config_file(); /* set hostname /after/ having read the config file */ if (*config->hostname) strcpy(hostname, config->hostname); cli_init_complete(hostname); update_config(); init_tbf(config->num_tbfs); LOG(0, 0, 0, "L2TPNS version " VERSION "\n"); LOG(0, 0, 0, "Copyright (c) 2012, 2013, 2014 ISP FDN & SAMESWIRELESS\n"); LOG(0, 0, 0, "Copyright (c) 2003, 2004, 2005, 2006 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 if(chdir("/tmp")) LOG(0, 0, 0, "Error chdir /tmp: %s\n", strerror(errno)); } 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; } } } initnetlink(); /* Set up the cluster communications port. */ if (cluster_init() < 0) exit(1); inittun(); LOG(1, 0, 0, "Set up on interface %s\n", config->tundevicename); if (*config->pppoe_if_to_bind) { init_pppoe(); LOG(1, 0, 0, "Set up on pppoe interface %s\n", config->pppoe_if_to_bind); } if (!config->nbmultiaddress) { config->bind_n_address[0] = config->bind_address; config->nbmultiaddress++; } config->nbudpfd = config->nbmultiaddress; for (i = 0; i < config->nbudpfd; i++) initudp(&udpfd[i], config->bind_n_address[i]); initlacudp(); config->indexlacudpfd = config->nbudpfd; udpfd[config->indexlacudpfd] = udplacfd; config->nbudpfd++; initcontrol(); initdae(); // Intercept snoopfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP); initrad(); initippool(); dhcpv6_init(); // 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)); } 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; if(!config->bind_portremotelns) config->bind_portremotelns = L2TPLACPORT; if(!config->bind_address_remotelns) config->bind_address_remotelns = INADDR_ANY; if (*config->bind_multi_address) { char *sip = config->bind_multi_address; char *n = sip; char *e = config->bind_multi_address + strlen(config->bind_multi_address); config->nbmultiaddress = 0; while (*sip && (sip < e)) { in_addr_t ip = 0; uint8_t u = 0; while (n < e && (*n == ',' || *n == ' ')) n++; while (n < e && (isdigit(*n) || *n == '.')) { if (*n == '.') { ip = (ip << 8) + u; u = 0; } else u = u * 10 + *n - '0'; n++; } ip = (ip << 8) + u; n++; if (ip) { config->bind_n_address[config->nbmultiaddress] = htonl(ip); config->iftun_n_address[config->nbmultiaddress] = htonl(ip); config->nbmultiaddress++; LOG(1, 0, 0, "Bind address %s\n", fmtaddr(htonl(ip), 0)); if (config->nbmultiaddress >= MAX_BINDADDR) break; } sip = n; } if (config->nbmultiaddress >= 1) { config->bind_address = config->bind_n_address[0]; config->iftun_address = config->bind_address; } } if(!config->iftun_address) { config->iftun_address = config->bind_address; config->iftun_n_address[0] = config->iftun_address; } if (*config->multi_hostname) { char *shost = config->multi_hostname; char *n = shost; char *e = config->multi_hostname + strlen(config->multi_hostname); config->nbmultihostname = 0; while (*shost && (shost < e)) { while ((n < e) && (*n == ' ' || *n == ',' || *n == '\t')) n++; i = 0; while (n < e && (*n != ',') && (*n != '\t')) { config->multi_n_hostname[config->nbmultihostname][i] = *n; n++;i++; } if (i > 0) { config->multi_n_hostname[config->nbmultihostname][i] = 0; LOG(1, 0, 0, "Bind Hostname %s\n", config->multi_n_hostname[config->nbmultihostname]); config->nbmultihostname++; if (config->nbmultihostname >= MAX_NBHOSTNAME) break; } shost = n; } if (config->nbmultihostname >= 1) { strcpy(hostname, config->multi_n_hostname[0]); strcpy(config->hostname, hostname); } } if (!*config->pppoe_ac_name) strncpy(config->pppoe_ac_name, DEFAULT_PPPOE_AC_NAME, sizeof(config->pppoe_ac_name) - 1); // 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]); } } // Guest change guest_accounts_num = 0; char *p2 = config->guest_user; while (p2 && *p2) { char *s = strpbrk(p2, " \t,"); if (s) { *s++ = 0; while (*s == ' ' || *s == '\t') s++; if (!*s) s = 0; } strcpy(guest_users[guest_accounts_num], p2); LOG(1, 0, 0, "Guest account[%d]: %s\n", guest_accounts_num, guest_users[guest_accounts_num]); guest_accounts_num++; p2 = s; } // Rebuild the guest_user array strcpy(config->guest_user, ""); int ui = 0; for (ui=0; uiguest_user, guest_users[ui]); if (uiguest_user, ","); } } 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_port) config->cluster_port = CLUSTERPORT; 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"); // Join a bundle if the MRRU option is accepted if(session[s].mrru > 0 && session[s].bundle == 0) { LOG(3, s, t, "This session can be part of multilink bundle\n"); if (join_bundle(s) > 0) cluster_send_bundle(session[s].bundle); else { LOG(0, s, t, "MPPP: Mismaching mssf option with other sessions in bundle\n"); sessionshutdown(s, "Mismaching mssf option.", CDN_NONE, TERM_SERVICE_UNAVAILABLE); return 0; } } 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) break; // Allow duplicate sessions for multilink ones of the same bundle. if (session[s].bundle && session[i].bundle && session[s].bundle == session[i].bundle) continue; if (ip == session[i].ip) { sessionshutdown(i, "Duplicate IP address", CDN_ADMIN_DISC, TERM_ADMIN_RESET); // close radius/routes, etc. continue; } if (config->allow_duplicate_users) continue; if (session[s].walled_garden || session[i].walled_garden) continue; // Guest change int found = 0; int gu; for (gu = 0; gu < guest_accounts_num; gu++) { if (!strcasecmp(user, guest_users[gu])) { found = 1; break; } } if (found) continue; // Drop the new session in case of duplicate sessionss, not the old one. if (!strcasecmp(user, session[i].user)) sessionshutdown(i, "Duplicate session for users", CDN_ADMIN_DISC, TERM_ADMIN_RESET); // close radius/routes, etc. } } // no need to set a route for the same IP address of the bundle if (!session[s].bundle || (bundle[session[s].bundle].num_of_links == 1)) { int routed = 0; // Add the route for this session. for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++) { if ((session[s].ip >> (32-session[s].route[r].prefixlen)) == (session[s].route[r].ip >> (32-session[s].route[r].prefixlen))) routed++; routeset(s, session[s].route[r].ip, session[s].route[r].prefixlen, 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 = session[s].last_data = 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].prefixlen != session[s].route[i].prefixlen) 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 >> (32-session[s].route[i].prefixlen)) == (session[s].route[i].ip >> (32-session[s].route[i].prefixlen))) routed++; routeset(s, session[s].route[i].ip, session[s].route[i].prefixlen, 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); } // remove old IPV6 routes... for (i = 0; i < MAXROUTE6 && session[s].route6[i].ipv6route.s6_addr[0] && session[s].route6[i].ipv6prefixlen; i++) { route6set(s, session[s].route6[i].ipv6route, session[s].route6[i].ipv6prefixlen, 0); } if (session[s].ipv6address.s6_addr[0]) { route6set(s, session[s].ipv6address, 128, 0); } routed = 0; // add new routes... for (i = 0; i < MAXROUTE && new->route[i].ip; i++) { if ((new->ip >> (32-new->route[i].prefixlen)) == (new->route[i].ip >> (32-new->route[i].prefixlen))) routed++; routeset(s, new->route[i].ip, new->route[i].prefixlen, 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->ppp.ipv6cp == Opened && session[s].ppp.ipv6cp != Opened) { for (i = 0; i < MAXROUTE6 && new->route6[i].ipv6prefixlen; i++) { route6set(s, new->route6[i].ipv6route, new->route6[i].ipv6prefixlen, 1); } } if (new->ipv6address.s6_addr[0] && new->ppp.ipv6cp == Opened && session[s].ppp.ipv6cp != Opened) { // Check if included in prefix if (sessionbyipv6(new->ipv6address) != s) route6set(s, new->ipv6address, 128, 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 %u\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 %u\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) && (i != TUNNEL_ID_PPPOE)) { LOG(4, 0, i, "Assigning tunnel ID %u\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, const 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_data; 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, const 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; } tunnelidt lac_new_tunnel() { return new_tunnel(); } void lac_tunnelclear(tunnelidt t) { tunnelclear(t); } void lac_send_SCCRQ(tunnelidt t, uint8_t * auth, unsigned int auth_len) { uint16_t version = 0x0100; // protocol version tunnel[t].state = TUNNELOPENING; // Sent SCCRQ - Start Control Connection Request controlt *c = controlnew(1); // sending SCCRQ controls(c, 7, config->multi_n_hostname[tunnel[t].indexudp][0]?config->multi_n_hostname[tunnel[t].indexudp]:hostname, 1); // host name controls(c, 8, Vendor_name, 1); // Vendor name control16(c, 2, version, 1); // protocol version control32(c, 3, 3, 1); // framing Capabilities control16(c, 9, t, 1); // assigned tunnel controlb(c, 11, (uint8_t *) auth, auth_len, 1); // CHAP Challenge LOG(3, 0, t, "Sent SCCRQ to REMOTE LNS\n"); controladd(c, 0, t); // send } void lac_send_ICRQ(tunnelidt t, sessionidt s) { // Sent ICRQ Incoming-call-request controlt *c = controlnew(10); // ICRQ control16(c, 14, s, 1); // assigned sesion call_serial_number++; control32(c, 15, call_serial_number, 1); // call serial number LOG(3, s, t, "Sent ICRQ to REMOTE LNS (far ID %u)\n", tunnel[t].far); controladd(c, 0, t); // send } void lac_tunnelshutdown(tunnelidt t, char *reason, int result, int error, char *msg) { tunnelshutdown(t, reason, result, error, msg); }