X-Git-Url: http://git.sameswireless.fr/l2tpns.git/blobdiff_plain/0c678c5a03bcdc601ea50bb7d8e273101cc5e557..5151ca40547c87612360f4115a9e17837f64d2b6:/l2tpns.c diff --git a/l2tpns.c b/l2tpns.c index 9671a69..3c90f6a 100644 --- a/l2tpns.c +++ b/l2tpns.c @@ -4,7 +4,7 @@ // Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced // vim: sw=8 ts=8 -char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.132 2005-09-15 09:34:48 bodea Exp $"; +char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.152 2005-12-14 02:19:15 bodea Exp $"; #include #include @@ -75,6 +75,10 @@ static int syslog_log = 0; // are we logging to syslog static FILE *log_stream = 0; // file handle for direct logging (i.e. direct into file, not via syslog). uint32_t last_id = 0; // Unique ID for radius accounting +// calculated from config->l2tp_mtu +uint16_t MRU = 0; // PPP MRU +uint16_t MSS = 0; // TCP MSS + struct cli_session_actions *cli_session_actions = NULL; // Pending session changes requested by CLI struct cli_tunnel_actions *cli_tunnel_actions = NULL; // Pending tunnel changes required by CLI @@ -92,7 +96,9 @@ uint32_t eth_tx = 0; static uint32_t ip_pool_size = 1; // Size of the pool of addresses used for dynamic address allocation. time_t time_now = 0; // Current time in seconds since epoch. static char time_now_string[64] = {0}; // Current time as a string. +static 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]; @@ -104,11 +110,11 @@ config_descriptt config_values[] = { CONFIG("log_file", log_filename, STRING), CONFIG("pid_file", pid_file, STRING), CONFIG("random_device", random_device, STRING), - CONFIG("l2tp_secret", l2tpsecret, STRING), + CONFIG("l2tp_secret", l2tp_secret, STRING), + CONFIG("l2tp_mtu", l2tp_mtu, INT), CONFIG("ppp_restart_time", ppp_restart_time, INT), CONFIG("ppp_max_configure", ppp_max_configure, INT), CONFIG("ppp_max_failure", ppp_max_failure, INT), - CONFIG("ppp_mru", ppp_mru, INT), CONFIG("primary_dns", default_dns1, IPv4), CONFIG("secondary_dns", default_dns2, IPv4), CONFIG("primary_radius", radiusserver[0], IPv4), @@ -156,6 +162,7 @@ static char *plugin_functions[] = { "plugin_control", "plugin_radius_response", "plugin_radius_reset", + "plugin_radius_account", "plugin_become_master", "plugin_new_session_master", }; @@ -184,7 +191,6 @@ static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s); static void free_ip_address(sessionidt s); static void dump_acct_info(int all); static void sighup_handler(int sig); -static void sigalrm_handler(int sig); static void 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); @@ -206,11 +212,17 @@ static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vec #define QUIT_SHUTDOWN 2 // SIGQUIT: shutdown sessions/tunnels, reject new connections // return internal time (10ths since process startup), set f if given +// as a side-effect sets time_now, and time_changed static clockt now(double *f) { struct timeval t; gettimeofday(&t, 0); if (f) *f = t.tv_sec + t.tv_usec / 1000000.0; + if (t.tv_sec != time_now) + { + time_now = t.tv_sec; + time_changed++; + } return (t.tv_sec - basetime) * 10 + t.tv_usec / 100000 + 1; } @@ -542,6 +554,13 @@ static void inittun(void) LOG(0, 0, 0, "Error setting tun queue length: %s\n", strerror(errno)); exit(1); } + /* set MTU to modem MRU + 4 (tun header) */ + ifr.ifr_mtu = MRU + 4; + if (ioctl(ifrfd, SIOCSIFMTU, (void *) &ifr) < 0) + { + LOG(0, 0, 0, "Error setting tun MTU: %s\n", strerror(errno)); + exit(1); + } ifr.ifr_flags = IFF_UP; if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0) { @@ -921,18 +940,14 @@ void tunnelsend(uint8_t * buf, uint16_t l, tunnelidt t) if (!t) { - static int backtrace_count = 0; LOG(0, 0, t, "tunnelsend called with 0 as tunnel id\n"); STAT(tunnel_tx_errors); - log_backtrace(backtrace_count, 5) return; } if (!tunnel[t].ip) { - static int backtrace_count = 0; LOG(1, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n"); - log_backtrace(backtrace_count, 5) STAT(tunnel_tx_errors); return; } @@ -950,7 +965,7 @@ void tunnelsend(uint8_t * buf, uint16_t l, tunnelidt t) { tunnel[t].last = time_now; // control message sent tunnel[t].retry = backoff(tunnel[t].try); // when to resend - if (tunnel[t].try > 1) + if (tunnel[t].try) { STAT(tunnel_retries); LOG(3, 0, t, "Control message resend try %d\n", tunnel[t].try); @@ -979,6 +994,61 @@ int tun_write(uint8_t * data, int size) return write(tunfd, data, size); } +// adjust tcp mss to avoid fragmentation (called only for tcp packets with syn set) +void adjust_tcp_mss(sessionidt s, tunnelidt t, uint8_t *buf, int len, uint8_t *tcp) +{ + int d = (tcp[12] >> 4) * 4; + uint8_t *mss = 0; + uint8_t *opts; + uint8_t *data; + uint16_t orig; + uint32_t sum; + + if ((tcp[13] & 0x3f) & ~(TCP_FLAG_SYN|TCP_FLAG_ACK)) // only want SYN and SYN,ACK + return; + + if (tcp + d > buf + len) // short? + return; + + opts = tcp + 20; + data = tcp + d; + + while (opts < data) + { + if (*opts == 2 && opts[1] == 4) // mss option (2), length 4 + { + mss = opts + 2; + if (mss + 2 > data) return; // short? + break; + } + + if (*opts == 0) return; // end of options + if (*opts == 1 || !opts[1]) // no op (one byte), or no length (prevent loop) + opts++; + else + opts += opts[1]; // skip over option + } + + if (!mss) return; // not found + orig = ntohs(*(uint16_t *) mss); + + if (orig <= MSS) return; // mss OK + + LOG(5, s, t, "TCP: %s:%u -> %s:%u SYN%s: adjusted mss from %u to %u\n", + fmtaddr(*(in_addr_t *) (buf + 12), 0), ntohs(*(uint16_t *) tcp), + fmtaddr(*(in_addr_t *) (buf + 16), 1), ntohs(*(uint16_t *) (tcp + 2)), + (tcp[13] & TCP_FLAG_ACK) ? ",ACK" : "", orig, MSS); + + // set mss + *(int16_t *) mss = htons(MSS); + + // adjust checksum (see rfc1141) + sum = orig + (~MSS & 0xffff); + sum += ntohs(*(uint16_t *) (tcp + 16)); + sum = (sum & 0xffff) + (sum >> 16); + *(uint16_t *) (tcp + 16) = htons(sum + (sum >> 16)); +} + // process outgoing (to tunnel) IP // static void processipout(uint8_t *buf, int len) @@ -1086,6 +1156,14 @@ static void processipout(uint8_t *buf, int len) if (session[s].filter_out && !ip_filter(buf, len, session[s].filter_out - 1)) return; + // adjust MSS on SYN and SYN,ACK packets with options + if ((ntohs(*(uint16_t *) (buf + 6)) & 0x1fff) == 0 && buf[9] == IPPROTO_TCP) // first tcp fragment + { + int ihl = (buf[0] & 0xf) * 4; // length of IP header + if (len >= ihl + 20 && (buf[ihl + 13] & TCP_FLAG_SYN) && ((buf[ihl + 12] >> 4) > 5)) + adjust_tcp_mss(s, t, buf, len, buf + ihl); + } + if (sp->tbf_out) { // Are we throttling this session? @@ -1095,7 +1173,8 @@ static void processipout(uint8_t *buf, int len) master_throttle_packet(sp->tbf_out, data, size); return; } - else if (sp->walled_garden && !config->cluster_iam_master) + + if (sp->walled_garden && !config->cluster_iam_master) { // We are walled-gardening this master_garden_packet(s, data, size); @@ -1607,6 +1686,7 @@ void sendipcp(sessionidt s, tunnelidt t) my_address; // send my IP tunnelsend(buf, 10 + (q - buf), t); // send it + restart_timer(s, ipcp); } void sendipv6cp(sessionidt s, tunnelidt t) @@ -1632,6 +1712,7 @@ void sendipv6cp(sessionidt s, tunnelidt t) q[13] = 1; tunnelsend(buf, 14 + (q - buf), t); // send it + restart_timer(s, ipv6cp); } static void sessionclear(sessionidt s) @@ -2009,7 +2090,7 @@ void processudp(uint8_t *buf, int len, struct sockaddr_in *addr) uint16_t orig_len; // handle hidden AVPs - if (!*config->l2tpsecret) + if (!*config->l2tp_secret) { LOG(1, s, t, "Hidden AVP requested, but no L2TP secret.\n"); fatal = flags; @@ -2252,9 +2333,9 @@ void processudp(uint8_t *buf, int len, struct sockaddr_in *addr) if (*p == 5 && p[1] == 6) // Magic-Number amagic = ntohl(*(uint32_t *) (p + 2)); else if (*p == 7) // Protocol-Field-Compression - aflags |= SESSIONPFC; + aflags |= SESSION_PFC; else if (*p == 8) // Address-and-Control-Field-Compression - aflags |= SESSIONACFC; + aflags |= SESSION_ACFC; p += p[1]; } } @@ -2381,19 +2462,17 @@ void processudp(uint8_t *buf, int len, struct sockaddr_in *addr) case 12: // ICCN if (amagic == 0) amagic = time_now; session[s].magic = amagic; // set magic number - session[s].l2tp_flags = aflags; // set flags received - session[s].mru = config->ppp_mru; + session[s].flags = aflags; // set flags received + session[s].mru = PPPMTU; // default controlnull(t); // ack // start LCP - sess_local[s].lcp.restart = time_now + config->ppp_restart_time; - sess_local[s].lcp.conf_sent = 1; - sess_local[s].lcp.nak_sent = 0; sess_local[s].lcp_authtype = config->radius_authprefer; - session[s].ppp.lcp = RequestSent; + sess_local[s].ppp_mru = MRU; sendlcp(s, t); - + change_state(s, lcp, RequestSent); break; + case 14: // CDN controlnull(t); // ack sessionshutdown(s, "Closed (Received CDN).", 0, 0); @@ -2532,31 +2611,9 @@ void processudp(uint8_t *buf, int len, struct sockaddr_in *addr) } else if (session[s].ppp.lcp == Opened) { - uint8_t buf[MAXETHER]; - uint8_t *q; - int mru = session[s].mru; - - if (!mru) mru = MAXMRU; - if (mru > sizeof(buf)) mru = sizeof(buf); - - l += 6; - if (l > mru) l = mru; - - q = makeppp(buf, sizeof(buf), 0, 0, s, t, proto); - if (!q) return; - - *q = CodeRej; - *(q + 1) = ++sess_local[s].lcp_ident; - *(uint16_t *)(q + 2) = l; - *(uint16_t *)(q + 4) = htons(proto); - memcpy(q + 6, p, l - 6); - - if (proto == PPPIPV6CP) - LOG(3, s, t, "LCP: send ProtocolRej (IPV6CP: not configured)\n"); - else - LOG(2, s, t, "LCP: sent ProtocolRej (0x%04X: unsupported)\n", proto); - - tunnelsend(buf, l + (q - buf), t); + session[s].last_packet = time_now; + if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; } + protoreject(s, t, p, l, proto); } else { @@ -2672,7 +2729,7 @@ static void regular_cleanups(double period) } } // Send hello - if (tunnel[t].state == TUNNELOPEN && (time_now - tunnel[t].lastrec) > 60) + if (tunnel[t].state == TUNNELOPEN && !tunnel[t].controlc && (time_now - tunnel[t].lastrec) > 60) { controlt *c = controlnew(6); // sending HELLO controladd(c, 0, t); // send the message @@ -2743,8 +2800,6 @@ static void regular_cleanups(double period) if (sess_local[s].lcp.conf_sent < config->ppp_max_configure) { LOG(3, s, session[s].tunnel, "No ACK for LCP ConfigReq... resending\n"); - sess_local[s].lcp.restart = time_now + config->ppp_restart_time; - sess_local[s].lcp.conf_sent++; sendlcp(s, session[s].tunnel); change_state(s, lcp, next_state); } @@ -2774,8 +2829,6 @@ static void regular_cleanups(double period) if (sess_local[s].ipcp.conf_sent < config->ppp_max_configure) { LOG(3, s, session[s].tunnel, "No ACK for IPCP ConfigReq... resending\n"); - sess_local[s].ipcp.restart = time_now + config->ppp_restart_time; - sess_local[s].ipcp.conf_sent++; sendipcp(s, session[s].tunnel); change_state(s, ipcp, next_state); } @@ -2805,8 +2858,6 @@ static void regular_cleanups(double period) if (sess_local[s].ipv6cp.conf_sent < config->ppp_max_configure) { LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq... resending\n"); - sess_local[s].ipv6cp.restart = time_now + config->ppp_restart_time; - sess_local[s].ipv6cp.conf_sent++; sendipv6cp(s, session[s].tunnel); change_state(s, ipv6cp, next_state); } @@ -2833,8 +2884,6 @@ static void regular_cleanups(double period) if (sess_local[s].ccp.conf_sent < config->ppp_max_configure) { LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq... resending\n"); - sess_local[s].ccp.restart = time_now + config->ppp_restart_time; - sess_local[s].ccp.conf_sent++; sendccp(s, session[s].tunnel); change_state(s, ccp, next_state); } @@ -2858,7 +2907,8 @@ static void regular_cleanups(double period) } // No data in ECHO_TIMEOUT seconds, send LCP ECHO - if (session[s].ppp.phase >= Establish && (time_now - session[s].last_packet >= ECHO_TIMEOUT)) + if (session[s].ppp.phase >= Establish && (time_now - session[s].last_packet >= ECHO_TIMEOUT) && + (time_now - sess_local[s].last_echo >= ECHO_TIMEOUT)) { uint8_t b[MAXETHER]; @@ -2873,6 +2923,7 @@ static void regular_cleanups(double period) LOG(4, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n", (int)(time_now - session[s].last_packet)); tunnelsend(b, 24, session[s].tunnel); // send it + sess_local[s].last_echo = time_now; s_actions++; } @@ -3162,9 +3213,17 @@ static void mainloop(void) int more = 0; int n; + + if (main_reload) + { + main_reload = 0; + read_config_file(); + config->reload_config++; + } + if (config->reload_config) { - // Update the config state based on config settings + config->reload_config = 0; update_config(); } @@ -3328,6 +3387,35 @@ static void mainloop(void) } } + 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) { @@ -3501,7 +3589,6 @@ static void initdata(int optdebug, char *optconfig) config->ppp_restart_time = 3; config->ppp_max_configure = 10; config->ppp_max_failure = 5; - config->ppp_mru = DEFAULT_MRU; strcpy(config->random_device, RANDOMDEVICE); log_stream = stderr; @@ -4004,14 +4091,13 @@ int main(int argc, char *argv[]) // Start the timer routine off time(&time_now); strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now)); - signal(SIGALRM, sigalrm_handler); - siginterrupt(SIGALRM, 0); initplugins(); initdata(optdebug, optconfig); init_cli(hostname); read_config_file(); + update_config(); init_tbf(config->num_tbfs); LOG(0, 0, 0, "L2TPNS version " VERSION "\n"); @@ -4087,8 +4173,6 @@ int main(int argc, char *argv[]) LOG(0, 0, 0, "Can't lock pages: %s\n", strerror(errno)); } - alarm(1); - // Drop privileges here if (config->target_uid > 0 && geteuid() == 0) setuid(config->target_uid); @@ -4110,53 +4194,11 @@ int main(int argc, char *argv[]) static void sighup_handler(int sig) { - if (log_stream) - { - if (log_stream != stderr) - fclose(log_stream); - - log_stream = NULL; - } - - read_config_file(); -} - -static void sigalrm_handler(int sig) -{ - // Log current traffic stats - - snprintf(config->bandwidth, sizeof(config->bandwidth), - "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u", - (udp_rx / 1024.0 / 1024.0 * 8), - (eth_tx / 1024.0 / 1024.0 * 8), - (eth_rx / 1024.0 / 1024.0 * 8), - (udp_tx / 1024.0 / 1024.0 * 8), - ((udp_tx + udp_rx + eth_tx + eth_rx) / 1024.0 / 1024.0 * 8), - udp_rx_pkt, eth_rx_pkt); - - udp_tx = udp_rx = 0; - udp_rx_pkt = eth_rx_pkt = 0; - eth_tx = eth_rx = 0; - - if (config->dump_speed) - printf("%s\n", config->bandwidth); - - // Update the internal time counter - time(&time_now); - strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now)); - alarm(1); - - { - // Run timer hooks - struct param_timer p = { time_now }; - run_plugins(PLUGIN_TIMER, &p); - } - + main_reload++; } static void shutdown_handler(int sig) { - LOG(1, 0, 0, "Shutting down\n"); main_quit = (sig == SIGQUIT) ? QUIT_SHUTDOWN : QUIT_FAILOVER; } @@ -4171,7 +4213,7 @@ static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challen MD5_CTX ctx; *challenge_response = NULL; - if (!*config->l2tpsecret) + if (!*config->l2tp_secret) { LOG(0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n"); return; @@ -4183,7 +4225,7 @@ static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challen MD5_Init(&ctx); MD5_Update(&ctx, &id, 1); - MD5_Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret)); + MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret)); MD5_Update(&ctx, challenge, challenge_length); MD5_Final(*challenge_response, &ctx); @@ -4250,7 +4292,16 @@ static void update_config() setbuf(log_stream, NULL); } - if (config->ppp_mru < 0) config->ppp_mru = 0; +#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 = PPPMTU; + 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; + MSS = MRU - TCP_HDRS; // Update radius config->numradiusservers = 0; @@ -4397,8 +4448,6 @@ static void update_config() LOG(0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno)); } } - - config->reload_config = 0; } static void read_config_file() @@ -4416,7 +4465,6 @@ static void read_config_file() cli_do_file(f); LOG(3, 0, 0, "Done reading config file\n"); fclose(f); - update_config(); } int sessionsetup(sessionidt s, tunnelidt t) @@ -5150,7 +5198,7 @@ static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vec // Compute initial pad MD5_Init(&ctx); MD5_Update(&ctx, (unsigned char *) &m, 2); - MD5_Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret)); + MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret)); MD5_Update(&ctx, vector, vec_len); MD5_Final(digest, &ctx); @@ -5163,7 +5211,7 @@ static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vec if (d >= sizeof(digest)) { MD5_Init(&ctx); - MD5_Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret)); + MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret)); MD5_Update(&ctx, last, sizeof(digest)); MD5_Final(digest, &ctx); @@ -5286,7 +5334,9 @@ int ip_filter(uint8_t *buf, int len, uint8_t filter) if (frag_offset) { - if (!rule->frag || rule->action == FILTER_ACTION_DENY) + // layer 4 deny rules are skipped + if (rule->action == FILTER_ACTION_DENY && + (rule->src_ports.op || rule->dst_ports.op || rule->tcp_flag_op)) continue; } else