send nsctl responses back using the correct source address
[l2tpns.git] / l2tpns.c
index d36fe59..27a5821 100644 (file)
--- 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 1.137 2005-09-16 06:10:21 bodea Exp $";
+char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.157 2006-04-05 01:45:57 bodea Exp $";
 
 #include <arpa/inet.h>
 #include <assert.h>
@@ -96,7 +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];
 
@@ -160,6 +162,7 @@ static char *plugin_functions[] = {
        "plugin_control",
        "plugin_radius_response",
        "plugin_radius_reset",
+       "plugin_radius_account",
        "plugin_become_master",
        "plugin_new_session_master",
 };
@@ -188,7 +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);
@@ -198,7 +200,7 @@ 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);
+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);
 
@@ -210,11 +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;
 }
 
@@ -546,6 +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 */
+       ifr.ifr_mtu = MRU;
+       if (ioctl(ifrfd, SIOCSIFMTU, (void *) &ifr) < 0)
+       {
+               LOG(0, 0, 0, "Error setting tun MTU: %s\n", strerror(errno));
+               exit(1);
+       }
        ifr.ifr_flags = IFF_UP;
        if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0)
        {
@@ -925,18 +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;
        }
@@ -954,7 +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);
@@ -1029,13 +1040,13 @@ void adjust_tcp_mss(sessionidt s, tunnelidt t, uint8_t *buf, int len, uint8_t *t
                (tcp[13] & TCP_FLAG_ACK) ? ",ACK" : "", orig, MSS);
 
        // set mss
-       *(int16_t *) mss = htns(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);
+       *(uint16_t *) (tcp + 16) = htons(sum + (sum >> 16));
 }
 
 // process outgoing (to tunnel) IP
@@ -1162,7 +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);
@@ -1674,6 +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)
@@ -1699,6 +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)
@@ -2319,9 +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];
                                                }
                                        }
@@ -2448,20 +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 = PPPMTU; // default
+                                       session[s].flags = aflags; // set flags received
+                                       session[s].mru = PPPoE_MRU; // 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;
                                        sess_local[s].ppp_mru = MRU;
-                                       session[s].ppp.lcp = RequestSent;
                                        sendlcp(s, t);
-
+                                       change_state(s, lcp, RequestSent);
                                        break;
+
                                case 14:      // CDN
                                        controlnull(t); // ack
                                        sessionshutdown(s, "Closed (Received CDN).", 0, 0);
@@ -2600,29 +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 > 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
                {
@@ -2738,7 +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
@@ -2809,8 +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);
                                }
@@ -2840,8 +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);
                                }
@@ -2871,8 +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);
                                }
@@ -2899,8 +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);
                                }
@@ -2924,7 +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];
 
@@ -2934,11 +2918,12 @@ static void regular_cleanups(double period)
                        *q = EchoReq;
                        *(uint8_t *)(q + 1) = (time_now % 255); // ID
                        *(uint16_t *)(q + 2) = htons(8); // Length
-                       *(uint32_t *)(q + 4) = 0; // Magic Number (not supported)
+                       *(uint32_t *)(q + 4) = session[s].ppp.lcp == Opened ? htonl(session[s].magic) : 0; // Magic Number
 
                        LOG(4, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
                                        (int)(time_now - session[s].last_packet));
                        tunnelsend(b, 24, session[s].tunnel); // send it
+                       sess_local[s].last_echo = time_now;
                        s_actions++;
                }
 
@@ -3228,9 +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();
                }
 
@@ -3255,6 +3248,7 @@ static void mainloop(void)
                if (n)
                {
                        struct sockaddr_in addr;
+                       struct in_addr local;
                        socklen_t alen;
                        int c, s;
                        int udp_ready = 0;
@@ -3271,6 +3265,7 @@ static void mainloop(void)
                        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
@@ -3297,20 +3292,30 @@ static void mainloop(void)
 
                                case FD_TYPE_CONTROL: // nsctl commands
                                        alen = sizeof(addr);
-                                       processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
+                                       s = recvfromto(controlfd, buf, sizeof(buf), MSG_WAITALL, (struct sockaddr *) &addr, &alen, &local);
+                                       if (s > 0) processcontrol(buf, s, &addr, alen, &local);
                                        n--;
                                        break;
 
                                case FD_TYPE_DAE: // DAE requests
                                        alen = sizeof(addr);
-                                       processdae(buf, recvfrom(daefd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
+                                       s = recvfrom(daefd, buf, sizeof(buf), MSG_WAITALL, (struct sockaddr *) &addr, &alen);
+                                       if (s > 0) processdae(buf, s, &addr, alen);
                                        n--;
                                        break;
 
                                case FD_TYPE_RADIUS: // RADIUS response
-                                       s = recv(radfds[d->index], buf, sizeof(buf), 0);
+                                       alen = sizeof(addr);
+                                       s = recvfrom(radfds[d->index], buf, sizeof(buf), MSG_WAITALL, (struct sockaddr *) &addr, &alen);
                                        if (s >= 0 && config->cluster_iam_master)
-                                               processrad(buf, s, d->index);
+                                       {
+                                               if (addr.sin_addr.s_addr == config->radiusserver[0] ||
+                                                   addr.sin_addr.s_addr == config->radiusserver[1])
+                                                       processrad(buf, s, d->index);
+                                               else
+                                                       LOG(3, 0, 0, "Dropping RADIUS packet from unknown source %s\n",
+                                                               fmtaddr(addr.sin_addr.s_addr, 0));
+                                       }
 
                                        n--;
                                        break;
@@ -3394,6 +3399,35 @@ 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)
                {
@@ -3927,7 +3961,7 @@ static void initippool()
                else
                {
                        // It's a single ip address
-                       add_to_ip_pool(inet_addr(pool), 0);
+                       add_to_ip_pool(ntohl(inet_addr(pool)), 0);
                }
        }
        fclose(f);
@@ -4069,14 +4103,13 @@ 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");
@@ -4152,8 +4185,6 @@ 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);
@@ -4175,53 +4206,11 @@ 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;
 }
 
@@ -4318,12 +4307,15 @@ static void update_config()
 #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;
+       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
@@ -4471,8 +4463,6 @@ 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()
@@ -4490,7 +4480,6 @@ 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)
@@ -4898,7 +4887,7 @@ static void plugins_done()
                run_plugin_done(p);
 }
 
-static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen)
+static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen, struct in_addr *local)
 {
        struct nsctl request;
        struct nsctl response;
@@ -5056,7 +5045,7 @@ static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int
        r = pack_control(buf, NSCTL_MAX_PKT_SZ, response.type, response.argc, response.argv);
        if (r > 0)
        {
-               sendto(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen);
+               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));
@@ -5360,7 +5349,9 @@ 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