Apply MLPPP patch from Muhammad Tayseer Alquoatli, very belatedly, with
[l2tpns.git] / l2tpns.c
index 545a3cd..f47ae66 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 1.172 2006/12/18 12:05:36 bodea Exp $";
+char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.173 2009/12/08 14:49:28 bodea Exp $";
 
 #include <arpa/inet.h>
 #include <assert.h>
@@ -74,6 +74,9 @@ static int tunidx;            // ifr_ifindex of tun device
 static int syslog_log = 0;     // are we logging to syslog
 static FILE *log_stream = 0;   // file handle for direct logging (i.e. direct into file, not via syslog).
 uint32_t last_id = 0;          // Unique ID for radius accounting
+// 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
@@ -133,6 +136,7 @@ config_descriptt config_values[] = {
        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),
@@ -1070,45 +1074,63 @@ void processmpframe(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l, uint8_t e
                l -= 4;
        }
 
-       // Process this frame
-       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 %u is closing.  Don't process PPP packets\n", s);
-                       return;              // closing session, PPP not processed
-               }
+        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);
+        }
+}
 
-               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 %u is closing.  Don't process PPP packets\n", s);
-                       return;              // closing session, PPP not processed
-               }
+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;
 
-               session[s].last_packet = session[s].last_data = time_now;
-               processipv6in(s, t, p, l);
-       }
-       else
-       {
-               LOG(2, s, t, "MPPP: Unsupported MP protocol 0x%04X received\n",proto);
-       }
+       sess_local[s].cout += len;      // To send to master..
+       sess_local[s].pout++;
 }
 
 // process outgoing (to tunnel) IP
@@ -1123,8 +1145,7 @@ static void processipout(uint8_t *buf, int len)
        uint8_t *data = buf;    // Keep a copy of the originals.
        int size = len;
 
-       uint8_t b1[MAXETHER + 20];
-       uint8_t b2[MAXETHER + 20];
+       uint8_t fragbuf[MAXETHER + 20];
 
        CSTAT(processipout);
 
@@ -1173,9 +1194,15 @@ static void processipout(uint8_t *buf, int 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];
-       sp->last_data = time_now;
 
        // DoS prevention: enforce a maximum number of packets per 0.1s for a session
        if (config->max_packets > 0)
@@ -1246,55 +1273,80 @@ static void processipout(uint8_t *buf, int len)
        }
 
        // Add on L2TP header
-       {
-               bundleidt bid = 0;
-               if (session[s].bundle && bundle[session[s].bundle].num_of_links > 1)
-               {
-                       bid = session[s].bundle;
-                       s = bundle[bid].members[bundle[bid].current_ses = ++bundle[bid].current_ses % bundle[bid].num_of_links];
-                       LOG(4, s, t, "MPPP: (1)Session number becomes: %u\n", s);
-                       if (len > 256)
-                       {
-                               // Partition the packet to 2 fragments
-                               uint32_t frag1len = len / 2;
-                               uint32_t frag2len = len - frag1len;
-                               uint8_t *p = makeppp(b1, sizeof(b1), buf, frag1len, s, t, PPPIP, 0, bid, MP_BEGIN);
-                               uint8_t *q;
-
-                               if (!p) return;
-                               tunnelsend(b1, frag1len + (p-b1), t); // send it...
-                               s = bundle[bid].members[bundle[bid].current_ses = ++bundle[bid].current_ses % bundle[bid].num_of_links];
-                               LOG(4, s, t, "MPPP: (2)Session number becomes: %u\n", s);
-                               q = makeppp(b2, sizeof(b2), buf+frag1len, frag2len, s, t, PPPIP, 0, bid, MP_END);
-                               if (!q) return;
-                               tunnelsend(b2, frag2len + (q-b2), t); // send it...
-                       }
-                       else {
-                               // Send it as one frame
-                               uint8_t *p = makeppp(b1, sizeof(b1), buf, len, s, t, PPPIP, 0, bid, MP_BOTH_BITS);
-                               if (!p) return;
-                               tunnelsend(b1, len + (p-b1), t); // send it...
-                       }
-               }
-               else
-               {
-                       uint8_t *p = makeppp(b1, sizeof(b1), buf, len, s, t, PPPIP, 0, 0, 0);
-                       if (!p) return;
-                       tunnelsend(b1, len + (p-b1), t); // send it...
-               }
-       }
+        {
+                bundleidt bid = 0;
+                if(session[s].bundle != 0 && bundle[session[s].bundle].num_of_links > 1)
+                {
+                        bid = session[s].bundle;
+                        s = bundle[bid].members[bundle[bid].current_ses = ++bundle[bid].current_ses % bundle[bid].num_of_links];
+                       t = session[s].tunnel;
+                       sp = &session[s];
+                        LOG(4, s, t, "MPPP: (1)Session number becomes: %d\n", s);
+                        if(len > MINFRAGLEN)
+                        {
+                                // Partition the packet to "bundle[b].num_of_links" fragments
+                               bundlet *b = &bundle[bid];
+                               uint32_t num_of_links = b->num_of_links;
+                                uint32_t fraglen = len / num_of_links;
+                               fraglen = (fraglen > session[s].mru ? session[s].mru : fraglen);
+                               uint32_t last_fraglen = fraglen + len % num_of_links;
+                               last_fraglen = (last_fraglen > session[s].mru ? len % num_of_links : last_fraglen);
+                               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)
+                               { 
+                                       s = b->members[b->current_ses = ++b->current_ses % num_of_links];
+                                       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
+                               s = b->members[b->current_ses = ++b->current_ses % num_of_links];
+                               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
+                {
+                        uint8_t *p = makeppp(fragbuf, sizeof(fragbuf), buf, len, s, t, PPPIP, 0, 0, 0);
+                        if (!p) return;
+                        tunnelsend(fragbuf, len + (p-fragbuf), 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);
 
-       increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
-       sp->cout_delta += len;
-       sp->pout++;
        udp_tx += len;
-
-       sess_local[s].cout += len;      // To send to master..
-       sess_local[s].pout++;
 }
 
 // process outgoing (to tunnel) IPv6
@@ -1661,7 +1713,9 @@ void filter_session(sessionidt s, int filter_in, int filter_out)
 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);
 
@@ -1710,21 +1764,52 @@ void sessionshutdown(sessionidt s, char const *reason, int cdn_result, int cdn_e
                            (session[s].route[r].ip & session[s].route[r].mask))
                                routed++;
 
-                       routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 0);
+                       if (del_routes) routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 0);
                        session[s].route[r].ip = 0;
                }
 
                if (session[s].ip_pool_index == -1) // static ip
                {
-                       if (!routed) routeset(s, session[s].ip, 0, 0, 0);
+                       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
-               if (session[s].ppp.ipv6cp == Opened && session[s].ipv6prefixlen)
+               if (session[s].ppp.ipv6cp == Opened && session[s].ipv6prefixlen && del_routes)
                        route6set(s, session[s].ipv6route, session[s].ipv6prefixlen, 0);
+               
+               if (b) 
+               {
+                       // This session was part of a bundle
+                       bundle[b].num_of_links--;
+                       LOG(3, s, 0, "MPPP: Dropping member link: %d from bundle %d\n",s,b);
+                       if(bundle[b].num_of_links == 0) 
+                       {
+                               bundleclear(b);
+                               LOG(3, s, 0, "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; ml<bundle[b].num_of_links; ml++)
+                                               if(bundle[b].members[ml] == s)
+                                               {
+                                                       mem_num = ml;
+                                                       break;
+                                               }
+                                       bundle[b].members[mem_num] = bundle[b].members[bundle[b].num_of_links];
+                                       LOG(3, s, 0, "MPPP: Adjusted member links array\n");
+                               }
+                       }
+                       cluster_send_bundle(b);
+               }
        }
 
        if (session[s].throttle_in || session[s].throttle_out) // Unthrottle if throttled.
@@ -1834,8 +1919,6 @@ static void sessionclear(sessionidt s)
 // kill a session now
 void sessionkill(sessionidt s, char *reason)
 {
-       bundleidt b;
-
        CSTAT(sessionkill);
 
        if (!session[s].opened) // not alive
@@ -1852,39 +1935,7 @@ void sessionkill(sessionidt s, char *reason)
        if (sess_local[s].radius)
                radiusclear(sess_local[s].radius, s); // cant send clean accounting data, session is killed
 
-       LOG(2, s, session[s].tunnel, "Kill session %u (%s): %s\n", s, session[s].user, reason);
-       if ((b = session[s].bundle))
-       {
-               // This session was part of a bundle
-               bundle[b].num_of_links--;
-               LOG(3, s, 0, "MPPP: Dropping member link: %u from bundle %u\n", s, b);
-               if (bundle[b].num_of_links == 0)
-               {
-                       bundleclear(b);
-                       LOG(3, s, 0, "MPPP: Kill bundle: %u (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; ml<bundle[b].num_of_links; ml++)
-                               {
-                                       if (bundle[b].members[ml] == s)
-                                       {
-                                               mem_num = ml;
-                                               break;
-                                       }
-                               }
-                               bundle[b].members[mem_num] = bundle[b].members[bundle[b].num_of_links];
-                               LOG(3, s, 0, "MPPP: Adjusted member links array\n");
-                       }
-               }
-               cluster_send_bundle(b);
-       }
+       LOG(2, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
        sessionclear(s);
        cluster_send_session(s);
 }
@@ -3911,6 +3962,7 @@ static void initdata(int optdebug, char *optconfig)
        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);
 
        log_stream = stderr;
@@ -4737,6 +4789,40 @@ static void update_config()
                }
        }
 
+       // 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; ui<guest_accounts_num; ui++)
+        {
+                strcat(config->guest_user, guest_users[ui]);
+                if (ui<guest_accounts_num-1)
+                {
+                        strcat(config->guest_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);
@@ -4815,6 +4901,20 @@ int sessionsetup(sessionidt s, tunnelidt t)
 
        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);
@@ -4832,14 +4932,6 @@ int sessionsetup(sessionidt s, tunnelidt t)
        // Make sure this is right
        session[s].tunnel = t;
 
-       // Join a bundle if the MRRU option is accepted
-       if (session[s].mrru > 0 && !session[s].bundle)
-       {
-               LOG(3, s, t, "This session can be part of multilink bundle\n");
-               if (join_bundle(s))
-                       cluster_send_bundle(session[s].bundle);
-       }
-
        // 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
@@ -4850,25 +4942,29 @@ int sessionsetup(sessionidt s, tunnelidt t)
                {
                        if (i == s) continue;
                        if (!session[s].opened) continue;
+                       // 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)
                        {
                                sessionkill(i, "Duplicate IP address");
                                continue;
                        }
 
-                       if (config->allow_duplicate_users)
-                               continue;
-
-                       if (session[s].walled_garden || session[i].walled_garden)
-                               continue;
-
-                       // Allow duplicate sessions for guest account.
-                       if (*config->guest_user && !strcasecmp(user, config->guest_user))
-                               continue;
-
-                       // 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 (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))
@@ -4876,6 +4972,8 @@ int sessionsetup(sessionidt s, tunnelidt t)
                }
        }
 
+       // 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;