// L2TPNS Global Stuff // $Id: l2tpns.h,v 1.44 2004-12-01 04:14:55 bodea Exp $ #ifndef __L2TPNS_H__ #define __L2TPNS_H__ #include #include #include #include #include #include #include #include #include #include #define VERSION "2.0.12" // Limits #define MAXTUNNEL 500 // could be up to 65535 #define MAXSESSION 50000 // could be up to 65535 #define MAXTBFS 6000 // Maximum token bucket filters. Might need up to 2 * session. #define RADIUS_SHIFT 5 #define RADIUS_MASK ((unsigned short)(((unsigned short)~0) >> (16 - RADIUS_SHIFT))) #define MAXRADIUS ((unsigned long)(1L << RADIUS_SHIFT) * 255) #define T_UNDEF (0xffff) // A tunnel ID that won't ever be used. Mark session as undefined. #define T_FREE (0) // A tunnel ID that won't ever be used. Mark session as free. #define MAXCONTROL 1000 // max length control message we ever send... #define MAXETHER (1500+18) // max packet we try sending to tun #define MAXTEL 96 // telephone number #define MAXPLUGINS 20 // maximum number of plugins to load #define MAXRADSERVER 10 // max radius servers #define MAXROUTE 10 // max static routes per session #define MAXIPPOOL 131072 // max number of ip addresses in pool #define RINGBUFFER_SIZE 10000 // Number of ringbuffer entries to allocate #define MAX_LOG_LENGTH 512 // Maximum size of log message #define ECHO_TIMEOUT 60 // Time between last packet sent and LCP ECHO generation #define IDLE_TIMEOUT 240 // Time between last packet sent and LCP ECHO generation #define BUSY_WAIT_TIME 3000 // 5 minutes in 1/10th seconds to wait for radius to cleanup on shutdown // Constants #ifndef ETCDIR #define ETCDIR "/etc/l2tpns" #endif #ifndef LIBDIR #define LIBDIR "/usr/lib/l2tpns" #endif #ifndef STATEDIR #define STATEDIR "/var/lib/l2tpns" #endif #ifndef PLUGINDIR #define PLUGINDIR LIBDIR // Plugins #endif #ifndef PLUGINCONF #define PLUGINCONF ETCDIR // Plugin config dir #endif #ifndef FLASHDIR #define FLASHDIR ETCDIR #endif #ifndef DATADIR #define DATADIR STATEDIR #endif #define TUNDEVICE "/dev/net/tun" #define STATEFILE DATADIR "/state.dump" // State dump file #define CONFIGFILE FLASHDIR "/startup-config" // Configuration file #define CLIUSERS FLASHDIR "/users" // CLI Users file #define IPPOOLFILE FLASHDIR "/ip_pool" // Address pool configuration #define ACCT_TIME 3000 // 5 minute accounting interval #define L2TPPORT 1701 // L2TP port #define RADPORT 1645 // old radius port... #define PKTARP 0x0806 // ARP packet type #define PKTIP 0x0800 // IP packet type #define PSEUDOMAC 0x0200 // pseudo MAC prefix (local significant MAC) #define PPPPAP 0xC023 #define PPPCHAP 0xC223 #define PPPLCP 0xC021 #define PPPIPCP 0x8021 #define PPPCCP 0x80FD #define PPPIP 0x0021 #define PPPMP 0x003D #define MIN_IP_SIZE 0x19 enum { ConfigReq = 1, ConfigAck, ConfigNak, ConfigRej, TerminateReq, TerminateAck, CodeRej, ProtocolRej, EchoReq, EchoReply, DiscardRequest, IdentRequest }; // Types typedef unsigned short u16; typedef unsigned int u32; typedef unsigned char u8; typedef u32 ipt; typedef u16 portt; typedef u16 sessionidt; typedef u16 tunnelidt; typedef u32 clockt; typedef u8 hasht[16]; // CLI actions struct cli_session_actions { char action; ipt snoop_ip; u16 snoop_port; int throttle_in; int throttle_out; int filter_in; int filter_out; }; #define CLI_SESS_KILL 0x01 #define CLI_SESS_SNOOP 0x02 #define CLI_SESS_NOSNOOP 0x04 #define CLI_SESS_THROTTLE 0x08 #define CLI_SESS_NOTHROTTLE 0x10 #define CLI_SESS_FILTER 0x20 #define CLI_SESS_NOFILTER 0x40 struct cli_tunnel_actions { char action; }; #define CLI_TUN_KILL 0x01 // dump header: update number if internal format changes #define DUMP_MAGIC "L2TPNS#" VERSION "#" // structures typedef struct // route { ipt ip; ipt mask; } routet; typedef struct controls // control message { struct controls *next; // next in queue u16 length; // length u8 buf[MAXCONTROL]; } controlt; typedef struct { sessionidt next; // next session in linked list sessionidt far; // far end session ID tunnelidt tunnel; // near end tunnel ID ipt ip; // IP of session set by RADIUS response (host byte order). int ip_pool_index; // index to IP pool unsigned long unique_id; // unique session id u16 nr; // next receive u16 ns; // next send u32 magic; // ppp magic number u32 cin, cout; // byte counts u32 pin, pout; // packet counts u32 total_cin; // This counter is never reset while a session is open u32 total_cout; // This counter is never reset while a session is open u32 id; // session id u16 throttle_in; // upstream throttle rate (kbps) u16 throttle_out; // downstream throttle rate clockt opened; // when started clockt die; // being closed, when to finally free time_t last_packet; // Last packet from the user (used for idle timeouts) ipt dns1, dns2; // DNS servers routet route[MAXROUTE]; // static routes u16 radius; // which radius session is being used (0 for not waiting on authentication) u16 mru; // maximum receive unit u16 tbf_in; // filter bucket for throttling in from the user. u16 tbf_out; // filter bucket for throttling out to the user. u8 l2tp_flags; // various bit flags from the ICCN on the l2tp tunnel. u8 reserved_old_snoop; // No longer used - remove at some time u8 walled_garden; // is this session gardened? u8 flags1; // additional flags (currently unused); char random_vector[MAXTEL]; int random_vector_length; char user[129]; // user (needed in seesion for radius stop messages) (can we reduce this? --mo) char called[MAXTEL]; // called number char calling[MAXTEL]; // calling number u32 tx_connect_speed; u32 rx_connect_speed; u32 flags; // Various session flags. ipt snoop_ip; // Interception destination IP u16 snoop_port; // Interception destination port u16 sid; // near end session id. u8 filter_in; // input filter index (to ip_filters[N-1]; 0 if none) u8 filter_out; // output filter index char reserved[18]; // Space to expand structure without changing HB_VERSION } sessiont; #define SF_IPCP_ACKED 1 // Has this session seen an IPCP Ack? #define SF_LCP_ACKED 2 // LCP negotiated #define SF_CCP_ACKED 4 // CCP negotiated typedef struct { u32 cin; u32 cout; } sessioncountt; #define SESSIONPFC 1 // PFC negotiated flags #define SESSIONACFC 2 // ACFC negotiated flags // 168 bytes per tunnel typedef struct { tunnelidt far; // far end tunnel ID ipt ip; // Ip for far end portt port; // port for far end u16 window; // Rx window u16 nr; // next receive u16 ns; // next send int state; // current state (tunnelstate enum) clockt last; // when last control message sent (used for resend timeout) clockt retry; // when to try resenting pending control clockt die; // being closed, when to finally free clockt lastrec; // when the last control message was received char hostname[128]; // tunnel hostname char vendor[128]; // LAC vendor u8 try; // number of retrys on a control message u16 controlc; // outstaind messages in queue controlt *controls; // oldest message controlt *controle; // newest message } tunnelt; // 180 bytes per radius session typedef struct // outstanding RADIUS requests { sessionidt session; // which session this applies to hasht auth; // request authenticator clockt retry; // when to try next char calling[MAXTEL]; // calling number char pass[129]; // password u8 id; // ID for PPP response u8 try; // which try we are on u8 state; // state of radius requests u8 chap; // set if CHAP used (is CHAP identifier) } radiust; typedef struct { ipt address; // Host byte order.. char assigned; // 1 if assigned, 0 if free sessionidt session; clockt last; // last used char user[129]; // user (try to have ip addresses persistent) } ippoolt; #ifdef RINGBUFFER struct Tringbuffer { struct { char level; sessionidt session; tunnelidt tunnel; char message[MAX_LOG_LENGTH]; } buffer[RINGBUFFER_SIZE]; int head; int tail; }; #endif /* * Possible tunnel states * TUNNELFREE -> TUNNELOPEN -> TUNNELDIE -> TUNNELFREE */ enum { TUNNELFREE, // Not in use TUNNELOPEN, // Active tunnel TUNNELDIE, // Currently closing TUNNELOPENING, // Busy opening TUNNELUNDEF, // Undefined }; enum { RADIUSNULL, // Not in use RADIUSCHAP, // sending CHAP down PPP RADIUSAUTH, // sending auth to RADIUS server RADIUSIPCP, // sending IPCP to end user RADIUSSTART, // sending start accounting to RADIUS server RADIUSSTOP, // sending stop accounting to RADIUS server RADIUSWAIT, // waiting timeout before available, in case delayed replies RADIUSDEAD, // errored while talking to radius server. }; struct Tstats { time_t start_time; time_t last_reset; unsigned long tun_rx_packets; unsigned long tun_tx_packets; unsigned long tun_rx_bytes; unsigned long tun_tx_bytes; unsigned long tun_rx_errors; unsigned long tun_tx_errors; unsigned long tunnel_rx_packets; unsigned long tunnel_tx_packets; unsigned long tunnel_rx_bytes; unsigned long tunnel_tx_bytes; unsigned long tunnel_rx_errors; unsigned long tunnel_tx_errors; unsigned long tunnel_retries; unsigned long radius_retries; unsigned long arp_sent; unsigned long packets_snooped; unsigned long tunnel_created; unsigned long session_created; unsigned long tunnel_timeout; unsigned long session_timeout; unsigned long radius_timeout; unsigned long radius_overflow; unsigned long tunnel_overflow; unsigned long session_overflow; unsigned long ip_allocated; unsigned long ip_freed; unsigned long c_forwarded; unsigned long recv_forward; #ifdef STATISTICS unsigned long call_processtun; unsigned long call_processipout; unsigned long call_processudp; unsigned long call_sessionbyip; unsigned long call_sessionbyuser; unsigned long call_sendarp; unsigned long call_sendipcp; unsigned long call_tunnelsend; unsigned long call_sessionkill; unsigned long call_sessionshutdown; unsigned long call_tunnelkill; unsigned long call_tunnelshutdown; unsigned long call_assign_ip_address; unsigned long call_free_ip_address; unsigned long call_dump_acct_info; unsigned long call_sessionsetup; unsigned long call_processpap; unsigned long call_processchap; unsigned long call_processlcp; unsigned long call_processipcp; unsigned long call_processipin; unsigned long call_processccp; unsigned long call_sendchap; unsigned long call_processrad; unsigned long call_radiussend; unsigned long call_radiusretry; #endif }; #ifdef STATISTICS #ifdef STAT_CALLS #define CSTAT(x) STAT(x) #else #define CSTAT(x) #endif #define STAT(x) (_statistics->x++) #define INC_STAT(x,y) (_statistics->x += (y)) #define GET_STAT(x) (_statistics->x) #define SET_STAT(x, y) (_statistics->x = (y)) #else #define CSTAT(x) #define STAT(x) #define INC_STAT(x,y) #define GET_STAT(x) 0 #define SET_STAT(x, y) #endif typedef struct { int debug; // debugging level time_t start_time; // time when l2tpns was started char bandwidth[256]; // current bandwidth char pid_file[256]; // file to write PID to on startup int wrote_pid; clockt current_time; // 1/10ths of a second since the process started. // means that we can only run a given process // for 13 years without re-starting! char config_file[128]; int reload_config; // flag to re-read config (set by cli) int cleanup_interval; // interval between regular cleanups (in seconds) int multi_read_count; // amount of packets to read per fd in processing loop char tundevice[10]; // tun device name char log_filename[128]; char l2tpsecret[64]; char radiussecret[64]; int radius_accounting; ipt radiusserver[MAXRADSERVER]; // radius servers u16 radiusport[MAXRADSERVER]; // radius base ports u8 numradiusservers; // radius server count short num_radfds; // Number of radius filehandles allocated ipt default_dns1, default_dns2; unsigned long rl_rate; // default throttle rate int num_tbfs; // number of throttle buckets int save_state; char accounting_dir[128]; ipt bind_address; ipt peer_address; int send_garp; // Set to true to garp for vip address on startup int target_uid; int dump_speed; char plugins[64][MAXPLUGINS]; char old_plugins[64][MAXPLUGINS]; int next_tbf; // Next HTB id available to use int scheduler_fifo; // If the system has multiple CPUs, use FIFO scheduling policy for this process. int lock_pages; // Lock pages into memory. int icmp_rate; // Max number of ICMP unreachable per second to send> u32 cluster_address; // Multicast address of cluster. // Send to this address to have everyone hear. char cluster_interface[64]; // Which interface to listen for multicast on. int cluster_iam_master; // Are we the cluster master??? int cluster_iam_uptodate; // Set if we've got a full set of state from the master. u32 cluster_master_address; // The network address of the cluster master. // Zero if i am the cluster master. int cluster_seq_number; // Sequence number of the next heartbeat we'll send out // (or the seq number we're next expecting if we're a slave). int cluster_undefined_sessions; // How many sessions we're yet to receive from the master. int cluster_undefined_tunnels; // How many tunnels we're yet to receive from the master. int cluster_highest_sessionid; int cluster_highest_tunnelid; clockt cluster_last_hb; // Last time we saw a heartbeat from the master. int cluster_num_changes; // Number of changes queued. int cluster_hb_interval; // How often to send a heartbeat. int cluster_hb_timeout; // How many missed heartbeats trigger an election. #ifdef BGP #define BGP_NUM_PEERS 2 u16 as_number; struct { char name[64]; u16 as; int keepalive; int hold; } neighbour[BGP_NUM_PEERS]; #endif } configt; enum config_typet { INT, STRING, UNSIGNED_LONG, SHORT, BOOL, IP, MAC }; typedef struct { char *key; int offset; int size; enum config_typet type; } config_descriptt; typedef struct { u8 op; // operation #define FILTER_PORT_OP_NONE 0 // all ports match #define FILTER_PORT_OP_EQ 1 #define FILTER_PORT_OP_NEQ 2 #define FILTER_PORT_OP_GT 3 #define FILTER_PORT_OP_LT 4 #define FILTER_PORT_OP_RANGE 5 portt port; // port (host byte order) portt port2; // range } ip_filter_portt; typedef struct { int action; // permit/deny #define FILTER_ACTION_DENY 1 #define FILTER_ACTION_PERMIT 2 u8 proto; // protocol: IPPROTO_* (netinet/in.h) ipt src_ip; // source ip (network byte order) ipt src_wild; ip_filter_portt src_ports; ipt dst_ip; // dest ip ipt dst_wild; ip_filter_portt dst_ports; u8 frag; // apply to non-initial fragments u8 tcp_flag_op; // match type: any, all, established #define FILTER_FLAG_OP_ANY 1 #define FILTER_FLAG_OP_ALL 2 #define FILTER_FLAG_OP_EST 3 u8 tcp_sflags; // flags set u8 tcp_cflags; // flags clear u32 counter; // match count } ip_filter_rulet; #define TCP_FLAG_FIN 0x01 #define TCP_FLAG_SYN 0x02 #define TCP_FLAG_RST 0x04 #define TCP_FLAG_PSH 0x08 #define TCP_FLAG_ACK 0x10 #define TCP_FLAG_URG 0x20 #define MAXFILTER 32 #define MAXFILTER_RULES 32 typedef struct { char name[32]; // ACL name int extended; // type: 0 = standard, 1 = extended ip_filter_rulet rules[MAXFILTER_RULES]; int used; // session ref count } ip_filtert; // arp.c void sendarp(int ifr_idx, const unsigned char* mac, ipt ip); // ppp.c void processpap(tunnelidt t, sessionidt s, u8 * p, u16 l); void processchap(tunnelidt t, sessionidt s, u8 * p, u16 l); void processlcp(tunnelidt t, sessionidt s, u8 * p, u16 l); void processipcp(tunnelidt t, sessionidt s, u8 * p, u16 l); void processipin(tunnelidt t, sessionidt s, u8 * p, u16 l); void processccp(tunnelidt t, sessionidt s, u8 * p, u16 l); void sendchap(tunnelidt t, sessionidt s); u8 *makeppp(u8 * b, int size, u8 * p, int l, tunnelidt t, sessionidt s, u16 mtype); void initlcp(tunnelidt t, sessionidt s); void send_ipin(sessionidt s, u8 * buf, int len); // radius.c void initrad(void); void radiussend(u16 r, u8 state); void processrad(u8 *buf, int len, char socket_index); void radiusretry(u16 r); u16 radiusnew(sessionidt s); void radiusclear(u16 r, sessionidt s); // l2tpns.c clockt backoff(u8 try); sessionidt sessionbyip(ipt ip); sessionidt sessionbyuser(char *username); void sessionshutdown(sessionidt s, char *reason); void send_garp(ipt ip); void tunnelsend(u8 * buf, u16 l, tunnelidt t); void sendipcp(tunnelidt t, sessionidt s); void processudp(u8 * buf, int len, struct sockaddr_in *addr); void snoop_send_packet(char *packet, u16 size, ipt destination, u16 port); int ip_filter(u8 *buf, int len, u8 filter); int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc); int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc); int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc); #undef LOG #undef LOG_HEX #define LOG(D, s, t, f, ...) ({ if (D <= config->debug) _log(D, s, t, f, ## __VA_ARGS__); }) #define LOG_HEX(D, t, d, s) ({ if (D <= config->debug) _log_hex(D, t, d, s); }) void _log(int level, sessionidt s, tunnelidt t, const char *format, ...) __attribute__((format (printf, 4, 5))); void _log_hex(int level, const char *title, const char *data, int maxsize); int sessionsetup(tunnelidt t, sessionidt s); int run_plugins(int plugin_type, void *data); void rebuild_address_pool(void); void throttle_session(sessionidt s, int rate_in, int rate_out); int load_session(sessionidt, sessiont *); void become_master(void); // We're the master; kick off any required master initializations. // cli.c void init_cli(char *hostname); void cli_do_file(FILE *fh); void cli_do(int sockfd); int cli_arg_help(struct cli_def *cli, int cr_ok, char *entry, ...); // icmp.c void host_unreachable(ipt destination, u16 id, ipt source, char *packet, int packet_len); extern tunnelt *tunnel; extern sessiont *session; extern sessioncountt *sess_count; extern ippoolt *ip_address_pool; #define sessionfree (session[0].next) #define log_backtrace(count, max) \ if (count++ < max) { \ void *array[20]; \ char **strings; \ int size, i; \ LOG(0, 0, t, "Backtrace follows"); \ size = backtrace(array, 10); \ strings = backtrace_symbols(array, size); \ if (strings) for (i = 0; i < size; i++) \ { \ LOG(0, 0, t, "%s\n", strings[i]); \ } \ free(strings); \ } extern configt *config; extern time_t basetime; // Time when this process started. extern time_t time_now; // Seconds since EPOCH. extern u32 last_id; extern struct Tstats *_statistics; extern ipt my_address; extern int tun_write(u8 *data, int size); extern int clifd; #define TIME (config->current_time) // macros for handling help in cli commands #define CLI_HELP_REQUESTED (argc > 0 && argv[argc-1][strlen(argv[argc-1])-1] == '?') #define CLI_HELP_NO_ARGS (argc > 1 || argv[0][1]) ? CLI_OK : cli_arg_help(cli, 1, NULL) // CVS identifiers (for "show version file") extern char const *cvs_id_arp; extern char const *cvs_id_cli; extern char const *cvs_id_cluster; extern char const *cvs_id_constants; extern char const *cvs_id_control; extern char const *cvs_id_icmp; extern char const *cvs_id_l2tpns; extern char const *cvs_id_ll; extern char const *cvs_id_md5; extern char const *cvs_id_ppp; extern char const *cvs_id_radius; extern char const *cvs_id_tbf; extern char const *cvs_id_util; #endif /* __L2TPNS_H__ */