remove defunct PLUGIN_PACKET_{RX,TX} constants
[l2tpns.git] / ppp.c
diff --git a/ppp.c b/ppp.c
index 901f8e5..afacd90 100644 (file)
--- a/ppp.c
+++ b/ppp.c
@@ -1,5 +1,6 @@
 // L2TPNS PPP Stuff
-// $Id: ppp.c,v 1.2 2004/03/05 00:09:03 fred_nerk Exp $
+
+char const *cvs_id_ppp = "$Id: ppp.c,v 1.100 2006/04/27 09:53:50 bodea Exp $";
 
 #include <stdio.h>
 #include <string.h>
 #include "constants.h"
 #include "plugin.h"
 #include "util.h"
+#include "tbf.h"
+#include "cluster.h"
 
 extern tunnelt *tunnel;
+extern bundlet *bundle;
+extern fragmentationt *frag;
 extern sessiont *session;
 extern radiust *radius;
-extern int tapfd;
-extern char hostname[1000];
-extern struct Tstats *_statistics;
-extern unsigned long eth_tx;
+extern int tunfd;
+extern char hostname[];
+extern uint32_t eth_tx;
 extern time_t time_now;
-extern struct configt *config;
+extern configt *config;
+
+static int add_lcp_auth(uint8_t *b, int size, int authtype);
+static bundleidt new_bundle(void);
+static int epdiscmp(epdist, epdist);
+static void setepdis(epdist *, epdist);
+static void ipcp_open(sessionidt s, tunnelidt t);
 
 // Process PAP messages
-void processpap(tunnelidt t, sessionidt s, u8 * p, u16 l)
+void processpap(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
 {
-       char user[129];
-       char pass[129];
+       char user[MAXUSER];
+       char pass[MAXPASS];
+       uint16_t hl;
+       uint16_t r;
 
-#ifdef STAT_CALLS
-       STAT(call_processpap);
-#endif
-       log_hex(5, "PAP", p, l);
+       CSTAT(processpap);
+
+       LOG_HEX(5, "PAP", p, l);
        if (l < 4)
        {
-               log(1, 0, s, t, "Short PAP %u bytes", l);
+               LOG(1, s, t, "Short PAP %u bytes\n", l);
                STAT(tunnel_rx_errors);
-               return ;
+               sessionshutdown(s, "Short PAP packet.", CDN_ADMIN_DISC, TERM_USER_ERROR);
+               return;
        }
-       if (*p != 1)
+
+       if ((hl = ntohs(*(uint16_t *) (p + 2))) > l)
        {
-               log(1, 0, s, t, "Unexpected PAP code %d\n", *p);
+               LOG(1, s, t, "Length mismatch PAP %u/%u\n", hl, l);
                STAT(tunnel_rx_errors);
-               return ;
+               sessionshutdown(s, "PAP length mismatch.", CDN_ADMIN_DISC, TERM_USER_ERROR);
+               return;
        }
-       if (ntohs(*(u16 *) (p + 2)) > l)
+       l = hl;
+
+       if (*p != 1)
        {
-               log(1, 0, s, t, "Length mismatch PAP %d/%d\n", ntohs(*(u16 *) (p + 2)), l);
+               LOG(1, s, t, "Unexpected PAP code %d\n", *p);
                STAT(tunnel_rx_errors);
-               return ;
+               sessionshutdown(s, "Unexpected PAP code.", CDN_ADMIN_DISC, TERM_USER_ERROR);
+               return;
+       }
+
+       if (session[s].ppp.phase != Authenticate)
+       {
+               LOG(2, s, t, "PAP ignored in %s phase\n", ppp_phase(session[s].ppp.phase));
+               return;
        }
+
        {
-               u8 *b = p;
+               uint8_t *b = p;
                b += 4;
+               user[0] = pass[0] = 0;
                if (*b && *b < sizeof(user))
+               {
                        memcpy(user, b + 1, *b);
-               user[*b] = 0;
-               b += 1 + *b;
-               if (*b && *b < sizeof(pass))
-                       memcpy(pass, b + 1, *b);
-               pass[*b] = 0;
-               log(3, 0, s, t, "PAP login %s/%s\n", user, pass);
+                       user[*b] = 0;
+                       b += 1 + *b;
+                       if (*b && *b < sizeof(pass))
+                       {
+                               memcpy(pass, b + 1, *b);
+                               pass[*b] = 0;
+                       }
+               }
+               LOG(3, s, t, "PAP login %s/%s\n", user, pass);
        }
-       if (session[s].ip || !session[s].radius)
+
+       if (session[s].ip || !(r = radiusnew(s)))
        {
                // respond now, either no RADIUS available or already authenticated
-               u8 b[MAXCONTROL];
-               u8 id = p[1];
-               u8 *p = makeppp(b, 0, 0, t, s, PPPPAP);
+               uint8_t b[MAXETHER];
+               uint8_t id = p[1];
+               uint8_t *p = makeppp(b, sizeof(b), 0, 0, s, t, PPPPAP, 0, 0, 0);
+               if (!p) return;
+
                if (session[s].ip)
-                       *p = 2;              // ACK
+                       *p = 2;                         // ACK
                else
-                       *p = 3;              // cant authorise
+                       *p = 3;                         // cant authorise
                p[1] = id;
-               *(u16 *) (p + 2) = htons(5); // length
-               p[4] = 0;               // no message
+               *(uint16_t *) (p + 2) = htons(5);       // length
+               p[4] = 0;                               // no message
+               tunnelsend(b, 5 + (p - b), t);          // send it
+
                if (session[s].ip)
                {
-                   log(3, session[s].ip, s, t, "%d Already an IP allocated: %s (%d)\n", getpid(), inet_toa(htonl(session[s].ip)), session[s].ip_pool_index);
+                       LOG(3, s, t, "Already an IP allocated: %s (%d)\n",
+                               fmtaddr(htonl(session[s].ip), 0), session[s].ip_pool_index);
                }
                else
                {
-                   log(1, 0, s, t, "No radius session available to authenticate session...\n");
+                       LOG(1, s, t, "No RADIUS session available to authenticate session...\n");
+                       sessionshutdown(s, "No free RADIUS sessions.", CDN_UNAVAILABLE, TERM_SERVICE_UNAVAILABLE);
                }
-               log(3, 0, s, t, "Fallback response to PAP (%s)\n", (session[s].ip) ? "ACK" : "NAK");
-               tunnelsend(b, 5 + (p - b), t); // send it
        }
        else
-       {                          // set up RADIUS request
-               u8 r = session[s].radius;
-
+       {
                // Run PRE_AUTH plugins
                struct param_pre_auth packet = { &tunnel[t], &session[s], strdup(user), strdup(pass), PPPPAP, 1 };
                run_plugins(PLUGIN_PRE_AUTH, &packet);
                if (!packet.continue_auth)
                {
-                       log(3, 0, s, t, "A plugin rejected PRE_AUTH\n");
+                       LOG(3, s, t, "A plugin rejected PRE_AUTH\n");
                        if (packet.username) free(packet.username);
                        if (packet.password) free(packet.password);
                        return;
@@ -107,73 +139,102 @@ void processpap(tunnelidt t, sessionidt s, u8 * p, u16 l)
                free(packet.password);
 
                radius[r].id = p[1];
-               log(3, 0, s, t, "Sending login for %s/%s to radius\n", user, pass);
+               LOG(3, s, t, "Sending login for %s/%s to RADIUS\n", user, pass);
                radiussend(r, RADIUSAUTH);
        }
 }
 
 // Process CHAP messages
-void processchap(tunnelidt t, sessionidt s, u8 * p, u16 l)
+void processchap(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
 {
-       u8 r;
-       u16 len;
-
-#ifdef STAT_CALLS
-       STAT(call_processchap);
-#endif
-       log_hex(5, "CHAP", p, l);
-       r = session[s].radius;
-       if (!r)
+       uint16_t r;
+       uint16_t hl;
+
+       CSTAT(processchap);
+
+       LOG_HEX(5, "CHAP", p, l);
+
+       if (l < 4)
        {
-               log(1, 0, s, t, "Unexpected CHAP message\n");
+               LOG(1, s, t, "Short CHAP %u bytes\n", l);
                STAT(tunnel_rx_errors);
+               sessionshutdown(s, "Short CHAP packet.", CDN_ADMIN_DISC, TERM_USER_ERROR);
                return;
        }
-       if (*p != 2)
+
+       if ((hl = ntohs(*(uint16_t *) (p + 2))) > l)
        {
-               log(1, 0, s, t, "Unexpected CHAP response code %d\n", *p);
+               LOG(1, s, t, "Length mismatch CHAP %u/%u\n", hl, l);
                STAT(tunnel_rx_errors);
+               sessionshutdown(s, "CHAP length mismatch.", CDN_ADMIN_DISC, TERM_USER_ERROR);
                return;
        }
-       if (p[1] != radius[r].id)
+       l = hl;
+
+       if (*p != 2)
        {
-               log(1, 0, s, t, "Wrong CHAP response ID %d (should be %d) (%d)\n", p[1], radius[r].id, r);
+               LOG(1, s, t, "Unexpected CHAP response code %d\n", *p);
                STAT(tunnel_rx_errors);
-               return ;
+               sessionshutdown(s, "CHAP length mismatch.", CDN_ADMIN_DISC, TERM_USER_ERROR);
+               return;
+       }
+
+       r = sess_local[s].radius;
+       if (!r)
+       {
+               LOG(3, s, t, "Unexpected CHAP message\n");
+               return;
+       }
+
+       if (session[s].ppp.phase != Authenticate)
+       {
+               LOG(2, s, t, "CHAP ignored in %s phase\n", ppp_phase(session[s].ppp.phase));
+               return;
        }
-       len = ntohs(*(u16 *) (p + 2));
-       if (len > l)
+
+       if (p[1] != radius[r].id)
        {
-               log(1, 0, s, t, "Bad CHAP length %d\n", len);
+               LOG(1, s, t, "Wrong CHAP response ID %d (should be %d) (%d)\n", p[1], radius[r].id, r);
                STAT(tunnel_rx_errors);
-               return ;
+               sessionshutdown(s, "Unexpected CHAP response ID.", CDN_ADMIN_DISC, TERM_USER_ERROR);
+               return;
        }
-       if (p[4] != 16)
+
+       if (l < 5 || p[4] != 16)
        {
-               log(1, 0, s, t, "Bad CHAP response length %d\n", p[4]);
+               LOG(1, s, t, "Bad CHAP response length %d\n", l < 5 ? -1 : p[4]);
                STAT(tunnel_rx_errors);
-               return ;
+               sessionshutdown(s, "Bad CHAP response length.", CDN_ADMIN_DISC, TERM_USER_ERROR);
+               return;
        }
-       if (len - 21 >= sizeof(session[s].user))
+
+       l -= 5;
+       p += 5;
+       if (l < 16 || l - 16 >= sizeof(session[s].user))
        {
-               log(1, 0, s, t, "CHAP user too long %d\n", len - 21);
+               LOG(1, s, t, "CHAP user too long %d\n", l - 16);
                STAT(tunnel_rx_errors);
-               return ;
+               sessionshutdown(s, "CHAP username too long.", CDN_ADMIN_DISC, TERM_USER_ERROR);
+               return;
        }
 
        // Run PRE_AUTH plugins
        {
                struct param_pre_auth packet = { &tunnel[t], &session[s], NULL, NULL, PPPCHAP, 1 };
 
-               packet.username = calloc(len-20, 1);
-               packet.password = calloc(16, 1);
-               memcpy(packet.username, p + 21, len - 21);
-               memcpy(packet.password, p + 5, 16);
+               packet.password = calloc(17, 1);
+               memcpy(packet.password, p, 16);
+
+               p += 16;
+               l -= 16;
+
+               packet.username = calloc(l + 1, 1);
+               memcpy(packet.username, p, l);
 
                run_plugins(PLUGIN_PRE_AUTH, &packet);
                if (!packet.continue_auth)
                {
-                       log(3, 0, s, t, "A plugin rejected PRE_AUTH\n");
+                       LOG(3, s, t, "A plugin rejected PRE_AUTH\n");
                        if (packet.username) free(packet.username);
                        if (packet.password) free(packet.password);
                        return;
@@ -187,48 +248,33 @@ void processchap(tunnelidt t, sessionidt s, u8 * p, u16 l)
        }
 
        radius[r].chap = 1;
+       LOG(3, s, t, "CHAP login %s\n", session[s].user);
        radiussend(r, RADIUSAUTH);
-       log(3, 0, s, t, "CHAP login %s\n", session[s].user);
 }
 
-char *ppp_lcp_types[] = {
-       NULL,
-       "ConfigReq",
-       "ConfigAck",
-       "ConfigNak",
-       "ConfigRej",
-       "TerminateReq",
-       "TerminateAck",
-       "CodeRej",
-       "ProtocolRej",
-       "EchoReq",
-       "EchoReply",
-       "DiscardRequest",
-};
-
-void dumplcp(char *p, int l)
+static void dumplcp(uint8_t *p, int l)
 {
-       signed int x = l - 3;
-       char *o = (p + 3);
+       int x = l - 4;
+       uint8_t *o = (p + 4);
 
-       log_hex(5, "PPP LCP Packet", p, l);
-       log(4, 0, 0, 0, "PPP LCP Packet type %d (%s)\n", *p, ppp_lcp_types[(int)*p]);
-       log(4, 0, 0, 0, "Length: %d\n", l);
+       LOG_HEX(5, "PPP LCP Packet", p, l);
+       LOG(4, 0, 0, "PPP LCP Packet type %d (%s len %d)\n", *p, ppp_code((int)*p), ntohs( ((uint16_t *) p)[1]) );
+       LOG(4, 0, 0, "Length: %d\n", l);
        if (*p != ConfigReq && *p != ConfigRej && *p != ConfigAck)
                return;
 
        while (x > 2)
        {
-               int type = *(u8 *)(o);
-               int length = *(u8 *)(o + 1);
-               if (length == 0)
+               int type = o[0];
+               int length = o[1];
+               if (length < 2)
                {
-                       log(4, 0, 0, 0, "       Option length is 0...\n");
+                       LOG(4, 0, 0, "  Option length is %d...\n", length);
                        break;
                }
                if (type == 0)
                {
-                       log(4, 0, 0, 0, "       Option type is 0...\n");
+                       LOG(4, 0, 0, "  Option type is 0...\n");
                        x -= length;
                        o += length;
                        continue;
@@ -236,41 +282,58 @@ void dumplcp(char *p, int l)
                switch (type)
                {
                        case 1: // Maximum-Receive-Unit
-                               log(4, 0, 0, 0, "    %s %d\n", lcp_types[type], ntohs(*(u16 *)(o + 2)));
+                               if (length == 4)
+                                       LOG(4, 0, 0, "    %s %d\n", ppp_lcp_option(type), ntohs(*(uint16_t *)(o + 2)));
+                               else
+                                       LOG(4, 0, 0, "    %s odd length %d\n", ppp_lcp_option(type), length);
+                               break;
+                       case 2: // Async-Control-Character-Map
+                               if (length == 6)
+                               {
+                                       uint32_t asyncmap = ntohl(*(uint32_t *)(o + 2));
+                                       LOG(4, 0, 0, "    %s %x\n", ppp_lcp_option(type), asyncmap);
+                               }
+                               else
+                                       LOG(4, 0, 0, "    %s odd length %d\n", ppp_lcp_option(type), length);
                                break;
                        case 3: // Authentication-Protocol
+                               if (length == 4)
                                {
-                                       int proto = ntohs(*(u16 *)(o + 2));
-                                       log(4, 0, 0, 0, "    %s %s\n", lcp_types[type],
-                                                       proto == 0xC223 ? "CHAP" : "PAP");
-                                       break;
+                                       int proto = ntohs(*(uint16_t *)(o + 2));
+                                       LOG(4, 0, 0, "    %s 0x%x (%s)\n", ppp_lcp_option(type), proto,
+                                               proto == PPPPAP  ? "PAP"  : "UNSUPPORTED");
                                }
-                       case 5: // Magic-Number
+                               else if (length == 5)
                                {
-                                       u32 magicno = ntohl(*(u32 *)(o + 2));
-                                       log(4, 0, 0, 0, "    %s %x\n", lcp_types[type], magicno);
-                                       break;
+                                       int proto = ntohs(*(uint16_t *)(o + 2));
+                                       int algo = *(o + 4);
+                                       LOG(4, 0, 0, "    %s 0x%x 0x%x (%s)\n", ppp_lcp_option(type), proto, algo,
+                                               (proto == PPPCHAP && algo == 5) ? "CHAP MD5"  : "UNSUPPORTED");
                                }
+                               else
+                                       LOG(4, 0, 0, "    %s odd length %d\n", ppp_lcp_option(type), length);
+                               break;
                        case 4: // Quality-Protocol
                                {
-                                       u32 qp = ntohl(*(u32 *)(o + 2));
-                                       log(4, 0, 0, 0, "    %s %x\n", lcp_types[type], qp);
-                                       break;
+                                       uint32_t qp = ntohl(*(uint32_t *)(o + 2));
+                                       LOG(4, 0, 0, "    %s %x\n", ppp_lcp_option(type), qp);
                                }
-                       case 7: // Protocol-Field-Compression
+                               break;
+                       case 5: // Magic-Number
+                               if (length == 6)
                                {
-                                       u32 pfc = ntohl(*(u32 *)(o + 2));
-                                       log(4, 0, 0, 0, "    %s %x\n", lcp_types[type], pfc);
-                                       break;
+                                       uint32_t magicno = ntohl(*(uint32_t *)(o + 2));
+                                       LOG(4, 0, 0, "    %s %x\n", ppp_lcp_option(type), magicno);
                                }
+                               else
+                                       LOG(4, 0, 0, "    %s odd length %d\n", ppp_lcp_option(type), length);
+                               break;
+                       case 7: // Protocol-Field-Compression
                        case 8: // Address-And-Control-Field-Compression
-                               {
-                                       u32 afc = ntohl(*(u32 *)(o + 2));
-                                       log(4, 0, 0, 0, "    %s %x\n", lcp_types[type], afc);
-                                       break;
-                               }
+                               LOG(4, 0, 0, "    %s\n", ppp_lcp_option(type));
+                               break;
                        default:
-                               log(2, 0, 0, 0, "    Unknown PPP LCP Option type %d\n", type);
+                               LOG(2, 0, 0, "    Unknown PPP LCP Option type %d\n", type);
                                break;
                }
                x -= length;
@@ -278,448 +341,2091 @@ void dumplcp(char *p, int l)
        }
 }
 
-// Process LCP messages
-void processlcp(tunnelidt t, sessionidt s, u8 * p, u16 l)
+void lcp_open(sessionidt s, tunnelidt t)
 {
-       u8 b[MAXCONTROL];
-       u8 *q = NULL;
+       // transition to Authentication or Network phase: 
+       session[s].ppp.phase = sess_local[s].lcp_authtype ? Authenticate : Network;
 
-#ifdef STAT_CALLS
-       STAT(call_processlcp);
-#endif
-       log_hex(5, "LCP", p, l);
-       if (l < 4)
-       {
-               log(1, session[s].ip, s, t, "Short LCP %d bytes", l);
-               STAT(tunnel_rx_errors);
-               return ;
-       }
-       if (*p == ConfigAck)
+       LOG(3, s, t, "LCP: Opened, phase %s\n", ppp_phase(session[s].ppp.phase));
+
+       // LCP now Opened
+       change_state(s, lcp, Opened);
+
+       if (session[s].ppp.phase == Authenticate)
        {
-               log(3, session[s].ip, s, t, "LCP: Discarding ConfigAck\n");
+               if (sess_local[s].lcp_authtype == AUTHCHAP)
+                       sendchap(s, t);
        }
-       else if (*p == ConfigReq)
+       else
        {
-               signed int x = l - 1;
-               char *o = (p + 1);
-
-               log(3, session[s].ip, s, t, "LCP: ConfigReq (%d bytes)...\n", l);
-
-               while (x > 2)
-               {
-                       int type = *(u8 *)(o);
-                       int length = *(u8 *)(o + 1);
-                       if (length == 0 || type == 0) break;
-                       switch (type)
-                       {
-                               case 1: // Maximum-Receive-Unit
-                                       session[s].mru = ntohs(*(u16 *)(o + 2));
-                                       break;
-                               case 3: // Authentication-Protocol
-                                       {
-                                               int proto = ntohs(*(u16 *)(o + 2));
-                                               if (proto == 0xC223)
-                                               {
-                                                       log(2, session[s].ip, s, t, "    Remote end is trying to do CHAP. Rejecting it.\n");
-
-                                                       if (!q)
-                                                       {
-                                                               q = makeppp(b, p, l, t, s, PPPLCP);
-                                                               *q++ = ConfigNak;
-                                                       }
-                                                       memcpy(q, o, length);
-                                                       *(u16 *)(q += 2) = htons(0xC023); // NAK -> Use PAP instead
-                                                       q += length;
-                                               }
-                                               break;
-                                       }
-                               case 5: // Magic-Number
-                                       {
-//                                             u32 magicno = ntohl(*(u32 *)(o + 2));
-                                               break;
-                                       }
-                               case 4: // Quality-Protocol
-                                       {
-//                                             u32 qp = ntohl(*(u32 *)(o + 2));
-                                               break;
-                                       }
-                               case 7: // Protocol-Field-Compression
-                                       {
-//                                             u32 pfc = ntohl(*(u32 *)(o + 2));
-                                               break;
-                                       }
-                               case 8: // Address-And-Control-Field-Compression
-                                       {
-//                                             u32 afc = ntohl(*(u32 *)(o + 2));
-                                               break;
-                                       }
-                               default:
-                                       log(2, session[s].ip, s, t, "    Unknown PPP LCP Option type %d\n", type);
-                                       break;
-                       }
-                       x -= length;
-                       o += length;
-               }
-
-               if (!q)
+               if (session[s].bundle && bundle[session[s].bundle].num_of_links > 1)
                {
-                       // Send back a ConfigAck
-                       log(3, session[s].ip, s, t, "ConfigReq accepted, sending as Ack\n");
-                       q = makeppp(b, p, l, t, s, PPPLCP);
-                       *q = ConfigAck;
-                       tunnelsend(b, l + (q - b), t);
+                       sessionidt first_ses = bundle[session[s].bundle].members[0];
+                       LOG(3, s, t, "MPPP: Skipping IPCP negotiation for session:%d, first session of bundle is:%d\n", s, first_ses);
+                       session[s].ip = session[first_ses].ip;
+                       session[s].dns1 = session[first_ses].dns1;
+                       session[s].dns2 = session[first_ses].dns2;
+                       session[s].timeout = session[first_ses].timeout;
+                       ipcp_open(s, t);
                }
                else
                {
-                       // Already built a ConfigNak... send it
-                       log(3, session[s].ip, s, t, "Sending ConfigNak\n");
-                       tunnelsend(b, l + (q - b), t);
+                       // This-Layer-Up
+                       sendipcp(s, t);
+                       change_state(s, ipcp, RequestSent);
+                       // move to passive state for IPv6 (if configured), CCP
+                       if (config->ipv6_prefix.s6_addr[0])
+                               change_state(s, ipv6cp, Stopped);
+                       else
+                               change_state(s, ipv6cp, Closed);
 
-                       log(3, session[s].ip, s, t, "Sending ConfigReq, requesting PAP login\n");
-                       q = makeppp(b, NULL, 0, t, s, PPPLCP);
-                       *q++ = ConfigReq;
-                       *(u8 *)(q++) = 3;
-                       *(u8 *)(q++) = 4;
-                       *(u16 *)(q += 2) = htons(0xC023);
-                       tunnelsend(b, l + (q - b), t);
+                       change_state(s, ccp, Stopped);
                }
        }
-       else if (*p == ConfigNak)
+}
+
+static void lcp_restart(sessionidt s)
+{
+       session[s].ppp.phase = Establish;
+       // This-Layer-Down
+       change_state(s, ipcp, Dead);
+       change_state(s, ipv6cp, Dead);
+       change_state(s, ccp, Dead);
+}
+
+static uint8_t *ppp_conf_rej(sessionidt s, uint8_t *buf, size_t blen, uint16_t mtype,
+       uint8_t **response, uint8_t *queued, uint8_t *packet, uint8_t *option)
+{
+       if (!*response || **response != ConfigRej)
        {
-               log(1, session[s].ip, s, t, "Remote end sent a ConfigNak. Ignoring\n");
-               dumplcp(p, l);
-               return ;
+               queued = *response = makeppp(buf, blen, packet, 2, s, session[s].tunnel, mtype, 0, 0, 0);
+               if (!queued)
+                       return 0;
+
+               *queued = ConfigRej;
+               queued += 4;
        }
-       else if (*p == TerminateReq)
+
+       if ((queued - buf + option[1]) > blen)
        {
-               *p = TerminateAck;     // close
-               q = makeppp(b, p, l, t, s, PPPLCP);
-               log(3, session[s].ip, s, t, "LCP: Received TerminateReq. Sending TerminateAck\n");
-               sessionshutdown(s, "Remote end closed connection.");
-               tunnelsend(b, l + (q - b), t); // send it
+               LOG(2, s, session[s].tunnel, "PPP overflow for ConfigRej (proto %u, option %u).\n", mtype, *option);
+               return 0;
        }
-       else if (*p == TerminateReq)
+
+       memcpy(queued, option, option[1]);
+       return queued + option[1];
+}
+
+static uint8_t *ppp_conf_nak(sessionidt s, uint8_t *buf, size_t blen, uint16_t mtype,
+       uint8_t **response, uint8_t *queued, uint8_t *packet, uint8_t *option,
+       uint8_t *value, size_t vlen)
+{
+       int *nak_sent;
+       switch (mtype)
        {
-               sessionshutdown(s, "Remote end closed connection.");
+       case PPPLCP:    nak_sent = &sess_local[s].lcp.nak_sent;    break;
+       case PPPIPCP:   nak_sent = &sess_local[s].ipcp.nak_sent;   break;
+       case PPPIPV6CP: nak_sent = &sess_local[s].ipv6cp.nak_sent; break;
+       default:        return 0; // ?
        }
-       else if (*p == EchoReq)
+
+       if (*response && **response != ConfigNak)
        {
-               *p = EchoReply;      // reply
-               *(u32 *) (p + 4) = htonl(session[s].magic); // our magic number
-               q = makeppp(b, p, l, t, s, PPPLCP);
-               log(4, session[s].ip, s, t, "LCP: Received EchoReq. Sending EchoReply\n");
-               tunnelsend(b, l + (q - b), t); // send it
+               if (*nak_sent < config->ppp_max_failure) // reject queued
+                       return queued;
+
+               return ppp_conf_rej(s, buf, blen, mtype, response, 0, packet, option);
        }
-       else if (*p == EchoReply)
+
+       if (!*response)
        {
-               // Ignore it, last_packet time is set earlier than this.
+               if (*nak_sent >= config->ppp_max_failure)
+                       return ppp_conf_rej(s, buf, blen, mtype, response, 0, packet, option);
+
+               queued = *response = makeppp(buf, blen, packet, 2, s, session[s].tunnel, mtype, 0, 0, 0);
+               if (!queued)
+                       return 0;
+
+               (*nak_sent)++;
+               *queued = ConfigNak;
+               queued += 4;
        }
-       else
+
+       if ((queued - buf + vlen + 2) > blen)
        {
-               log(1, session[s].ip, s, t, "Unexpected LCP code %d\n", *p);
-               STAT(tunnel_rx_errors);
-               return ;
+               LOG(2, s, session[s].tunnel, "PPP overflow for ConfigNak (proto %u, option %u).\n", mtype, *option);
+               return 0;
        }
+
+       *queued++ = *option;
+       *queued++ = vlen + 2;
+       memcpy(queued, value, vlen);
+       return queued + vlen;
 }
 
-// Process IPCP messages
-void processipcp(tunnelidt t, sessionidt s, u8 * p, u16 l)
+static void ppp_code_rej(sessionidt s, tunnelidt t, uint16_t proto,
+       char *pname, uint8_t *p, uint16_t l, uint8_t *buf, size_t size)
+{
+       uint8_t *q;
+       int mru = session[s].mru;
+       if (mru < MINMTU) mru = MINMTU;
+       if (mru > size) mru = size;
+
+       l += 4;
+       if (l > mru) l = mru;
+
+       q = makeppp(buf, size, 0, 0, s, t, proto, 0, 0, 0);
+       if (!q) return;
+
+       *q = CodeRej;
+       *(q + 1) = ++sess_local[s].lcp_ident;
+       *(uint16_t *)(q + 2) = htons(l);
+       memcpy(q + 4, p, l - 4);
+
+       LOG(2, s, t, "Unexpected %s code %s\n", pname, ppp_code(*p));
+       LOG(3, s, t, "%s: send %s\n", pname, ppp_code(*q));
+       if (config->debug > 3) dumplcp(q, l);
+
+       tunnelsend(buf, l + (q - buf), t);
+}
+
+// Process LCP messages
+void processlcp(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
 {
-#ifdef STAT_CALLS
-       STAT(call_processipcp);
-#endif
-       log_hex(5, "IPCP", p, l);
-       if (l < 5)
+       uint8_t b[MAXETHER];
+       uint8_t *q = NULL;
+       uint16_t hl;
+
+       CSTAT(processlcp);
+
+       LOG_HEX(5, "LCP", p, l);
+       if (l < 4)
        {
-               log(1, 0, s, t, "Short IPCP %d bytes", l);
+               LOG(1, s, t, "Short LCP %d bytes\n", l);
                STAT(tunnel_rx_errors);
                return ;
        }
-       if (*p == ConfigAck)
-       {                          // happy with our IPCP
-               u8 r = session[s].radius;
-               if ((!r || radius[r].state == RADIUSIPCP) && !session[s].servicenet)
-                       if (!r)
-                               r = radiusnew(s);
-                       if (r)
-                               radiussend(r, RADIUSSTART); // send radius start, having got IPCP at last
-               return ;                 // done
-       }
-       if (*p != ConfigReq)
-       {
-               log(1, 0, s, t, "Unexpected IPCP code %d\n", *p);
-               STAT(tunnel_rx_errors);
-               return ;
-       }
-       if (ntohs(*(u16 *) (p + 2)) > l)
+
+       if ((hl = ntohs(*(uint16_t *) (p + 2))) > l)
        {
-               log(1, 0, s, t, "Length mismatch IPCP %d/%d\n", ntohs(*(u16 *) (p + 2)), l);
+               LOG(1, s, t, "Length mismatch LCP %u/%u\n", hl, l);
                STAT(tunnel_rx_errors);
                return ;
        }
-       if (!session[s].ip)
-       {
-               log(3, 0, s, t, "Waiting on radius reply\n");
-               return ;                   // have to wait on RADIUS eply
-       }
-       // form a config reply quoting the IP in the session
+       l = hl;
+
+       if (session[s].die) // going down...
+               return;
+
+       LOG((*p == EchoReq || *p == EchoReply) ? 4 : 3, s, t,
+               "LCP: recv %s\n", ppp_code(*p));
+
+       if (config->debug > 3) dumplcp(p, l);
+
+       if (*p == ConfigAck)
        {
-               u8 b[MAXCONTROL];
-               u8 *i,
-               *q;
+               int x = l - 4;
+               uint8_t *o = (p + 4);
+               int authtype = 0;
 
-               q = p + 4;
-               i = p + l;
-               while (q < i && q[1])
-               {
-                       if (*q != 0x81 && *q != 0x83 && *q != 3)
-                               break;
-                       q += q[1];
-               }
-               if (q < i)
-               {                       // reject
-                       u16 n = 4;
-                       i = p + l;
-                       q = makeppp(b, p, l, t, s, PPPIPCP);
-                       *q = ConfigRej;
-                       p += 4;
-                       while (p < i && p[1])
-                       {
-                               if (*p != 0x81 && *p != 0x83 && *p != 3)
-                               {
-                                       log(2, 0, s, t, "IPCP reject %d\n", *p);
-                                       memcpy(q + n, p, p[1]);
-                                       n += p[1];
-                               }
-                               p += p[1];
-                       }
-                       *(u16 *) (q + 2) = htons(n);
-                       tunnelsend(b, n + (q - b), t); // send it
-               }
-               else
+               while (x > 2)
                {
-                       *p = ConfigAck;
-                       i = findppp(p, 0x81); // Primary DNS address
-                       if (i)
-                       {
-                               if (*(u32 *) (i + 2) != htonl(session[s].dns1))
-                               {
-                                       *(u32 *) (i + 2) = htonl(session[s].dns1);
-                                       *p = ConfigNak;
-                               }
-                       }
-                       i = findppp(p, 0x83); // Secondary DNS address (TBA, is it)
-                       if (i)
-                       {
-                               if (*(u32 *) (i + 2) != htonl(session[s].dns2))
-                               {
-                                       *(u32 *) (i + 2) = htonl(session[s].dns2);
-                                       *p = ConfigNak;
-                               }
-                       }
-                       i = findppp(p, 3);   // IP address
-                       if (!i || i[1] != 6)
-                       {
-                               log(1, 0, s, t, "No IP in IPCP request\n");
-                               STAT(tunnel_rx_errors);
-                               return ;
-                       }
-                       if (*(u32 *) (i + 2) != htonl(session[s].ip))
+                       int type = o[0];
+                       int length = o[1];
+
+                       if (length == 0 || type == 0 || x < length) break;
+                       switch (type)
                        {
-                               *(u32 *) (i + 2) = htonl(session[s].ip);
-                               *p = ConfigNak;
+                               case 3: // Authentication-Protocol
+                                       {
+                                               int proto = ntohs(*(uint16_t *)(o + 2));
+                                               if (proto == PPPPAP)
+                                                       authtype = AUTHPAP;
+                                               else if (proto == PPPCHAP && *(o + 4) == 5)
+                                                       authtype = AUTHCHAP;
+                                       }
+
+                                       break;
                        }
-                       q = makeppp(b, p, l, t, s, PPPIPCP);
-                       tunnelsend(b, l + (q - b), t); // send it
+                       x -= length;
+                       o += length;
                }
-       }
-}
 
-// process IP packet received
-void processipin(tunnelidt t, sessionidt s, u8 * p, u16 l)
-{
-#ifdef STAT_CALLS
-       STAT(call_processipin);
-#endif
-       log_hex(5, "IP", p, l);
+               if (!session[s].ip && authtype)
+                       sess_local[s].lcp_authtype = authtype;
 
-       if (l > MAXETHER)
-       {
-               log(1, *(u32 *)(p + 12), s, t, "IP packet too long %d\n", l);
-               STAT(tunnel_rx_errors);
-               return ;
-       }
+               switch (session[s].ppp.lcp)
+               {
+               case RequestSent:
+                       initialise_restart_count(s, lcp);
+                       change_state(s, lcp, AckReceived);
+                       break;
 
-       session[s].cin += l;
-       session[s].total_cin += l;
-       session[s].pin++;
-       eth_tx += l;
+               case AckReceived:
+               case Opened:
+                       LOG(2, s, t, "LCP: ConfigAck in state %s?  Sending ConfigReq\n", ppp_state(session[s].ppp.lcp));
+                       if (session[s].ppp.lcp == Opened)
+                               lcp_restart(s);
 
-       // Add on the tun header
-       p -= 4;
-       *(u32 *)p = htonl(0x00000800);
-       l += 4;
+                       sendlcp(s, t);
+                       change_state(s, lcp, RequestSent);
+                       break;
 
-       // Plugin hook
-       {
-               struct param_packet_rx packet = { &tunnel[t], &session[s], p, l };
-               run_plugins(PLUGIN_PACKET_TX, &packet);
-       }
+               case AckSent:
+                       lcp_open(s, t);
+                       break;
 
-       // send to ethernet
-       if (write(tapfd, p, l) < 0)
-       {
-               STAT(tap_tx_errors);
-               log(0, 0, s, t, "Error writing %d bytes to TAP device: %s (tapfd=%d, p=%p)\n",
-                       l, strerror(errno), tapfd, p);
+               default:
+                       LOG(2, s, t, "LCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.lcp));
+               }
        }
-
-       if (session[s].snoop)
+       else if (*p == ConfigReq)
        {
-               // Snooping this session, send it to ASIO
-               snoop_send_packet(p, l);
-       }
-       STAT(tap_tx_packets);
-       INC_STAT(tap_tx_bytes, l);
-}
+               int x = l - 4;
+               uint8_t *o = (p + 4);
+               uint8_t *response = 0;
+               static uint8_t asyncmap[4] = { 0, 0, 0, 0 }; // all zero
+               static uint8_t authproto[5];
+               int changed = 0;
 
-// Process LCP messages
-void processccp(tunnelidt t, sessionidt s, u8 * p, u16 l)
-{
-#ifdef STAT_CALLS
-       STAT(call_processccp);
-#endif
-       log_hex(5, "CCP", p, l);
-       if (l < 2 || (*p != ConfigReq && *p != TerminateReq))
-       {
-               log(1, 0, s, t, "Unexpecetd CCP request code %d\n", *p);
-               STAT(tunnel_rx_errors);
-               return ;
-       }
-       // reject
-       {
-               u8 b[MAXCONTROL];
-               u8 *q;
-               if (*p == ConfigReq)
+               while (x > 2)
                {
-                       if (l < 6)
+                       int type = o[0];
+                       int length = o[1];
+
+                       if (length == 0 || type == 0 || x < length) break;
+                       switch (type)
                        {
-                               *p = ConfigAck;         // accept no compression
+                               case 1: // Maximum-Receive-Unit
+                                       {
+                                               uint16_t mru = ntohs(*(uint16_t *)(o + 2));
+                                               if (mru >= MINMTU)
+                                               {
+                                                       session[s].mru = mru;
+                                                       changed++;
+                                                       break;
+                                               }
+
+                                               LOG(3, s, t, "    Remote requesting MRU of %u.  Rejecting.\n", mru);
+                                               mru = htons(MRU);
+                                               q = ppp_conf_nak(s, b, sizeof(b), PPPLCP, &response, q, p, o, (uint8_t *) &mru, sizeof(mru));
+                                       }
+                                       break;
+
+                               case 2: // Async-Control-Character-Map
+                                       if (!ntohl(*(uint32_t *)(o + 2))) // all bits zero is OK
+                                               break;
+
+                                       LOG(3, s, t, "    Remote requesting asyncmap.  Rejecting.\n");
+                                       q = ppp_conf_nak(s, b, sizeof(b), PPPLCP, &response, q, p, o, asyncmap, sizeof(asyncmap));
+                                       break;
+
+                               case 3: // Authentication-Protocol
+                                       {
+                                               int proto = ntohs(*(uint16_t *)(o + 2));
+                                               char proto_name[] = "0x0000";
+                                               int alen;
+
+                                               if (proto == PPPPAP)
+                                               {
+                                                       if (config->radius_authtypes & AUTHPAP)
+                                                       {
+                                                               sess_local[s].lcp_authtype = AUTHPAP;
+                                                               break;
+                                                       }
+
+                                                       strcpy(proto_name, "PAP");
+                                               }
+                                               else if (proto == PPPCHAP)
+                                               {
+                                                       if (config->radius_authtypes & AUTHCHAP
+                                                           && *(o + 4) == 5) // MD5
+                                                       {
+                                                               sess_local[s].lcp_authtype = AUTHCHAP;
+                                                               break;
+                                                       }
+
+                                                       strcpy(proto_name, "CHAP");
+                                               }
+                                               else
+                                                       sprintf(proto_name, "%#4.4x", proto);
+
+                                               LOG(3, s, t, "    Remote requesting %s authentication.  Rejecting.\n", proto_name);
+
+                                               alen = add_lcp_auth(authproto, sizeof(authproto), config->radius_authprefer);
+                                               if (alen < 2) break; // paranoia
+
+                                               q = ppp_conf_nak(s, b, sizeof(b), PPPLCP, &response, q, p, o, authproto + 2, alen - 2);
+                                               if (q && *response == ConfigNak &&
+                                                       config->radius_authtypes != config->radius_authprefer)
+                                               {
+                                                       // alternate type
+                                                       alen = add_lcp_auth(authproto, sizeof(authproto), config->radius_authtypes & ~config->radius_authprefer);
+                                                       if (alen < 2) break;
+                                                       q = ppp_conf_nak(s, b, sizeof(b), PPPLCP, &response, q, p, o, authproto + 2, alen - 2);
+                                               }
+
+                                               break;
+                                       }
+                                       break;
+
+                               case 4: // Quality-Protocol
+                               case 5: // Magic-Number
+                               case 7: // Protocol-Field-Compression
+                               case 8: // Address-And-Control-Field-Compression
+                                       break;
+
+                               case 17: // Multilink Max-Receive-Reconstructed-Unit
+                                       {
+                                               uint16_t mrru = ntohs(*(uint16_t *)(o + 2));
+                                               session[s].mrru = mrru;
+                                               changed++;
+                                               LOG(3, s, t, "    Received PPP LCP option MRRU: %d\n",mrru);
+                                       }
+                                       break;
+                                       
+                               case 18: // Multilink Short Sequence Number Header Format
+                                       {
+                                               session[s].mssf = 1;
+                                               changed++;
+                                               LOG(3, s, t, "    Received PPP LCP option MSSN format\n");
+                                       }
+                                       break;
+                                       
+                               case 19: // Multilink Endpoint Discriminator
+                                       {
+                                               uint8_t epdis_class = o[2];
+                                               int addr;
+
+                                               session[s].epdis.addr_class = epdis_class;
+                                               session[s].epdis.length = length - 3;
+                                               if (session[s].epdis.length > 20)
+                                               {
+                                                       LOG(1, s, t, "Error: received EndDis Address Length more than 20: %d\n", session[s].epdis.length);
+                                                       session[s].epdis.length = 20;
+                                               }
+
+                                               for (addr = 0; addr < session[s].epdis.length; addr++)
+                                                       session[s].epdis.address[addr] = o[3+addr];
+
+                                               changed++;
+
+                                               switch (epdis_class)
+                                               {
+                                               case LOCALADDR:
+                                                       LOG(3, s, t, "    Received PPP LCP option Multilink EndDis Local Address Class: %d\n",epdis_class);
+                                                       break;
+                                               case IPADDR:
+                                                       LOG(3, s, t, "    Received PPP LCP option Multilink EndDis IP Address Class: %d\n",epdis_class);
+                                                       break;
+                                               case IEEEMACADDR:
+                                                       LOG(3, s, t, "    Received PPP LCP option Multilink EndDis IEEE MAC Address Class: %d\n",epdis_class);
+                                                       break;
+                                               case PPPMAGIC:
+                                                       LOG(3, s, t, "    Received PPP LCP option Multilink EndDis PPP Magic No Class: %d\n",epdis_class);
+                                                       break;
+                                               case PSNDN:
+                                                       LOG(3, s, t, "    Received PPP LCP option Multilink EndDis PSND No Class: %d\n",epdis_class);
+                                                       break;
+                                               default:
+                                                       LOG(3, s, t, "    Received PPP LCP option Multilink EndDis NULL Class %d\n",epdis_class);
+                                               }
+                                       }
+                                       break;
+
+                               default: // Reject any unknown options
+                                       LOG(3, s, t, "    Rejecting unknown PPP LCP option %d\n", type);
+                                       q = ppp_conf_rej(s, b, sizeof(b), PPPLCP, &response, q, p, o);
+                       }
+                       x -= length;
+                       o += length;
+               }
+
+               if (changed)
+                       cluster_send_session(s);
+
+               if (response)
+               {
+                       l = q - response; // LCP packet length
+                       *((uint16_t *) (response + 2)) = htons(l); // update header
+               }
+               else
+               {
+                       // Send packet back as ConfigAck
+                       response = makeppp(b, sizeof(b), p, l, s, t, PPPLCP, 0, 0, 0);
+                       if (!response) return;
+                       *response = ConfigAck;
+               }
+
+               switch (session[s].ppp.lcp)
+               {
+               case Closed:
+                       response = makeppp(b, sizeof(b), p, 2, s, t, PPPLCP, 0, 0, 0);
+                       if (!response) return;
+                       *response = TerminateAck;
+                       *((uint16_t *) (response + 2)) = htons(l = 4);
+                       break;
+
+               case Stopped:
+                       initialise_restart_count(s, lcp);
+                       sendlcp(s, t);
+                       if (*response == ConfigAck)
+                               change_state(s, lcp, AckSent);
+                       else
+                               change_state(s, lcp, RequestSent);
+
+                       break;
+
+               case RequestSent:
+                       if (*response == ConfigAck)
+                               change_state(s, lcp, AckSent);
+
+                       break;
+
+               case AckReceived:
+                       if (*response == ConfigAck)
+                               lcp_open(s, t);
+
+                       break;
+
+               case Opened:
+                       lcp_restart(s);
+                       sendlcp(s, t);
+                       /* fallthrough */
+
+               case AckSent:
+                       if (*response == ConfigAck)
+                               change_state(s, lcp, AckSent);
+                       else
+                               change_state(s, lcp, RequestSent);
+
+                       break;
+
+               default:
+                       LOG(2, s, t, "LCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.lcp));
+                       return;
+               }
+
+               LOG(3, s, t, "LCP: send %s\n", ppp_code(*response));
+               if (config->debug > 3) dumplcp(response, l);
+
+               tunnelsend(b, l + (response - b), t);
+       }
+       else if (*p == ConfigNak || *p == ConfigRej)
+       {
+               int x = l - 4;
+               uint8_t *o = (p + 4);
+               int authtype = -1;
+
+               while (x > 2)
+               {
+                       int type = o[0];
+                       int length = o[1];
+
+                       if (length == 0 || type == 0 || x < length) break;
+                       switch (type)
+                       {
+                               case 1: // Maximum-Receive-Unit
+                                       if (*p == ConfigNak)
+                                       {
+                                               if (length < 4) break;
+                                               sess_local[s].ppp_mru = ntohs(*(uint16_t *)(o + 2));
+                                               LOG(3, s, t, "    Remote requested MRU of %u\n", sess_local[s].ppp_mru);
+                                       }
+                                       else
+                                       {
+                                               sess_local[s].ppp_mru = 0;
+                                               LOG(3, s, t, "    Remote rejected MRU negotiation\n");
+                                       }
+
+                                       break;
+
+                               case 3: // Authentication-Protocol
+                                       if (authtype > 0)
+                                               break;
+
+                                       if (*p == ConfigNak)
+                                       {
+                                               int proto;
+
+                                               if (length < 4) break;
+                                               proto = ntohs(*(uint16_t *)(o + 2));
+
+                                               if (proto == PPPPAP)
+                                               {
+                                                       authtype = config->radius_authtypes & AUTHPAP;
+                                                       LOG(3, s, t, "    Remote requested PAP authentication...%sing\n",
+                                                               authtype ? "accept" : "reject");
+                                               }
+                                               else if (proto == PPPCHAP && length > 4 && *(o + 4) == 5)
+                                               {
+                                                       authtype = config->radius_authtypes & AUTHCHAP;
+                                                       LOG(3, s, t, "    Remote requested CHAP authentication...%sing\n",
+                                                               authtype ? "accept" : "reject");
+                                               }
+                                               else
+                                               {
+                                                       LOG(3, s, t, "    Rejecting unsupported authentication %#4x\n",
+                                                               proto);
+                                               }
+                                       }
+                                       else
+                                       {
+                                               LOG(2, s, t, "LCP: remote rejected auth negotiation\n");
+                                               authtype = 0; // shutdown
+                                       }
+
+                                       break;
+
+                               case 5: // Magic-Number
+                                       session[s].magic = 0;
+                                       if (*p == ConfigNak)
+                                       {
+                                               if (length < 6) break;
+                                               session[s].magic = ntohl(*(uint32_t *)(o + 2));
+                                       }
+
+                                       if (session[s].magic)
+                                               LOG(3, s, t, "    Remote requested magic-no %x\n", session[s].magic);
+                                       else
+                                               LOG(3, s, t, "    Remote rejected magic-no\n");
+
+                                       cluster_send_session(s);
+                                       break;
+
+                               case 17: // Multilink Max-Receive-Reconstructed-Unit
+                               {
+                                       if (*p == ConfigNak)
+                                       {
+                                               sess_local[s].mp_mrru = ntohs(*(uint16_t *)(o + 2));
+                                               LOG(3, s, t, "    Remote requested MRRU of %u\n", sess_local[s].mp_mrru);
+                                       }
+                                       else
+                                       {
+                                               sess_local[s].mp_mrru = 0;
+                                               LOG(3, s, t, "    Remote rejected MRRU negotiation\n");
+                                       }
+                               }
+                               break;
+
+                               case 18: // Multilink Short Sequence Number Header Format
+                               {
+                                       if (*p == ConfigNak)
+                                       {
+                                               sess_local[s].mp_mssf = 0;
+                                               LOG(3, s, t, "    Remote requested Naked mssf\n");
+                                       }
+                                       else
+                                       {
+                                               sess_local[s].mp_mssf = 0;
+                                               LOG(3, s, t, "    Remote rejected mssf\n");
+                                       }
+                               }
+                               break;
+
+                               case 19: // Multilink Endpoint Discriminator
+                               {
+                                       if (*p == ConfigNak)
+                                       {
+                                               LOG(2, s, t, "    Remote should not configNak Endpoint Dis!\n");
+                                       }
+                                       else
+                                       {
+                                               sess_local[s].mp_epdis = 0;
+                                               LOG(3, s, t, "    Remote rejected Endpoint Discriminator\n");
+                                       }
+                               }
+                               break;
+
+                               default:
+                                       LOG(2, s, t, "LCP: remote sent %s for type %u?\n", ppp_code(*p), type);
+                                       sessionshutdown(s, "Unable to negotiate LCP.", CDN_ADMIN_DISC, TERM_USER_ERROR);
+                                       return;
+                       }
+                       x -= length;
+                       o += length;
+               }
+
+               if (!authtype)
+               {
+                       sessionshutdown(s, "Unsupported authentication.", CDN_ADMIN_DISC, TERM_USER_ERROR);
+                       return;
+               }
+
+               if (authtype > 0)
+                       sess_local[s].lcp_authtype = authtype;
+
+               switch (session[s].ppp.lcp)
+               {
+               case Closed:
+               case Stopped:
+                       {
+                               uint8_t *response = makeppp(b, sizeof(b), p, 2, s, t, PPPLCP, 0, 0, 0);
+                               if (!response) return;
+                               *response = TerminateAck;
+                               *((uint16_t *) (response + 2)) = htons(l = 4);
+
+                               LOG(3, s, t, "LCP: send %s\n", ppp_code(*response));
+                               if (config->debug > 3) dumplcp(response, l);
+
+                               tunnelsend(b, l + (response - b), t);
+                       }
+                       break;
+
+               case RequestSent:
+               case AckSent:
+                       initialise_restart_count(s, lcp);
+                       sendlcp(s, t);
+                       break;
+
+               case AckReceived:
+                       LOG(2, s, t, "LCP: ConfigNak in state %s?  Sending ConfigReq\n", ppp_state(session[s].ppp.lcp));
+                       sendlcp(s, t);
+                       break;
+
+               case Opened:
+                       lcp_restart(s);
+                       sendlcp(s, t);
+                       break;
+
+               default:
+                       LOG(2, s, t, "LCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.lcp));
+                       return;
+               }
+       }
+       else if (*p == TerminateReq)
+       {
+               switch (session[s].ppp.lcp)
+               {
+               case Closed:
+               case Stopped:
+               case Closing:
+               case Stopping:
+               case RequestSent:
+               case AckReceived:
+               case AckSent:
+                       break;
+
+               case Opened:
+                       lcp_restart(s);
+                       zero_restart_count(s, lcp);
+                       change_state(s, lcp, Closing);
+                       break;
+
+               default:
+                       LOG(2, s, t, "LCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.lcp));
+                       return;
+               }
+
+               *p = TerminateAck;      // send ack
+               q = makeppp(b, sizeof(b),  p, l, s, t, PPPLCP, 0, 0, 0);
+               if (!q) return;
+
+               LOG(3, s, t, "LCP: send %s\n", ppp_code(*q));
+               if (config->debug > 3) dumplcp(q, l);
+
+               tunnelsend(b, l + (q - b), t); // send it
+       }
+       else if (*p == ProtocolRej)
+       {
+               uint16_t proto = 0;
+
+               if (l > 4)
+               {
+                       proto = *(p+4);
+                       if (l > 5 && !(proto & 1))
+                       {
+                               proto <<= 8;
+                               proto |= *(p+5);
+                       }
+               }
+
+               if (proto == PPPIPV6CP)
+               {
+                       LOG(3, s, t, "IPv6 rejected\n");
+                       change_state(s, ipv6cp, Closed);
+               }
+               else
+               {
+                       LOG(3, s, t, "LCP protocol reject: 0x%04X\n", proto);
+               }
+       }
+       else if (*p == EchoReq)
+       {
+               *p = EchoReply;         // reply
+               *(uint32_t *) (p + 4) = htonl(session[s].magic); // our magic number
+               q = makeppp(b, sizeof(b), p, l, s, t, PPPLCP, 0, 0, 0);
+               if (!q) return;
+
+               LOG(4, s, t, "LCP: send %s\n", ppp_code(*q));
+               if (config->debug > 3) dumplcp(q, l);
+
+               tunnelsend(b, l + (q - b), t); // send it
+       }
+       else if (*p == EchoReply)
+       {
+               // Ignore it, last_packet time is set earlier than this.
+       }
+       else if (*p != CodeRej)
+       {
+               ppp_code_rej(s, t, PPPLCP, "LCP", p, l, b, sizeof(b));
+       }
+}
+
+int join_bundle(sessionidt s)
+{
+       // Search for a bundle to join
+       bundleidt i;
+       bundleidt b;
+       for (i = 1; i < MAXBUNDLE; i++)
+       {
+               if (bundle[i].state != BUNDLEFREE)
+               {
+                       if (epdiscmp(session[s].epdis,bundle[i].epdis) && !strcmp(session[s].user, bundle[i].user))
+                       {
+                               session[s].bundle = i;
+                               bundle[i].mrru = session[s].mrru;
+                               bundle[i].mssf = session[s].mssf;
+                               if (session[s].epdis.length > 0)
+                                       setepdis(&bundle[i].epdis, session[s].epdis);
+
+                               strcpy(bundle[i].user, session[s].user);
+                               bundle[i].members[bundle[i].num_of_links] = s;
+                               bundle[i].num_of_links++;
+                               LOG(3, s, session[s].tunnel, "MPPP: Bundling additional line in bundle (%d), lines:%d\n",i,bundle[i].num_of_links);
+                               return i;
+                       }
+               }
+       }
+
+       // No previously created bundle was found for this session, so create a new one
+       if (!(b = new_bundle())) return 0;
+
+       session[s].bundle = b;
+       bundle[b].mrru = session[s].mrru;
+       bundle[b].mssf = session[s].mssf;
+       if (session[s].epdis.length > 0)
+               setepdis(&bundle[b].epdis, session[s].epdis);
+
+       strcpy(bundle[b].user, session[s].user);
+       bundle[b].members[0] = s;
+       LOG(3, s, session[s].tunnel, "MPPP: Created a new bundle (%d)\n", b);
+       return b;
+}
+
+static int epdiscmp(epdist ep1, epdist ep2)
+{
+       int ad;
+       if (ep1.length != ep2.length)
+               return 0;
+
+       if (ep1.addr_class != ep2.addr_class)
+               return 0;
+
+       for (ad = 0; ad < ep1.length; ad++)
+               if (ep1.address[ad] != ep2.address[ad])
+                       return 0;
+
+       return 1;
+}
+
+static void setepdis(epdist *ep1, epdist ep2)
+{
+       int ad;
+       ep1->length = ep2.length;
+       ep1->addr_class = ep2.addr_class;
+       for (ad = 0; ad < ep2.length; ad++)
+               ep1->address[ad] = ep2.address[ad];
+}
+
+static bundleidt new_bundle()
+{
+       bundleidt i;
+       for (i = 1; i < MAXBUNDLE; i++)
+       {
+               if (bundle[i].state == BUNDLEFREE)
+               {
+                       LOG(4, 0, 0, "MPPP: Assigning bundle ID %d\n", i);
+                       bundle[i].num_of_links = 1;
+                       bundle[i].last_check = time_now;        // Initialize last_check value
+                       bundle[i].state = BUNDLEOPEN;
+                       bundle[i].current_ses = -1;     // This is to enforce the first session 0 to be used at first
+                       if (i > config->cluster_highest_bundleid)
+                               config->cluster_highest_bundleid = i;
+                       return i;
+               }
+       }
+       LOG(0, 0, 0, "MPPP: Can't find a free bundle! There shouldn't be this many in use!\n");
+       return 0;
+}
+
+static void ipcp_open(sessionidt s, tunnelidt t)
+{
+       LOG(3, s, t, "IPCP: Opened, session is now active\n");
+
+       change_state(s, ipcp, Opened);
+
+       if (!(session[s].walled_garden || session[s].flags & SESSION_STARTED))
+       {
+               uint16_t r = radiusnew(s);
+               if (r)
+               {
+                       radiussend(r, RADIUSSTART); // send radius start
+
+                       // don't send further Start records if IPCP is restarted
+                       session[s].flags |= SESSION_STARTED;
+                       cluster_send_session(s);
+               }
+       }
+
+       // start IPv6 if configured and still in passive state
+       if (session[s].ppp.ipv6cp == Stopped)
+       {
+               sendipv6cp(s, t);
+               change_state(s, ipv6cp, RequestSent);
+       }
+}
+
+// Process IPCP messages
+void processipcp(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
+{
+       uint8_t b[MAXETHER];
+       uint8_t *q = 0;
+       uint16_t hl;
+
+       CSTAT(processipcp);
+
+       LOG_HEX(5, "IPCP", p, l);
+       if (l < 4)
+       {
+               LOG(1, s, t, "Short IPCP %d bytes\n", l);
+               STAT(tunnel_rx_errors);
+               return ;
+       }
+
+       if ((hl = ntohs(*(uint16_t *) (p + 2))) > l)
+       {
+               LOG(1, s, t, "Length mismatch IPCP %u/%u\n", hl, l);
+               STAT(tunnel_rx_errors);
+               return ;
+       }
+       l = hl;
+
+       if (session[s].ppp.phase < Network)
+       {
+               LOG(2, s, t, "IPCP %s ignored in %s phase\n", ppp_code(*p), ppp_phase(session[s].ppp.phase));
+               return;
+       }
+
+       LOG(3, s, t, "IPCP: recv %s\n", ppp_code(*p));
+
+       if (*p == ConfigAck)
+       {
+               switch (session[s].ppp.ipcp)
+               {
+               case RequestSent:
+                       initialise_restart_count(s, ipcp);
+                       change_state(s, ipcp, AckReceived);
+                       break;
+
+               case AckReceived:
+               case Opened:
+                       LOG(2, s, t, "IPCP: ConfigAck in state %s?  Sending ConfigReq\n", ppp_state(session[s].ppp.ipcp));
+                       sendipcp(s, t);
+                       change_state(s, ipcp, RequestSent);
+                       break;
+
+               case AckSent:
+                       ipcp_open(s, t);
+                       break;
+
+               default:
+                       LOG(2, s, t, "IPCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.ipcp));
+               }
+       }
+       else if (*p == ConfigReq)
+       {
+               uint8_t *response = 0;
+               uint8_t *o = p + 4;
+               int length = l - 4;
+               int gotip = 0;
+               in_addr_t addr;
+
+               while (length > 2)
+               {
+                       if (!o[1] || o[1] > length) return;
+
+                       switch (*o)
+                       {
+                       case 3: // ip address
+                               gotip++; // seen address
+                               if (o[1] != 6) return;
+
+                               addr = htonl(session[s].ip);
+                               if (memcmp(o + 2, &addr, (sizeof addr)))
+                               {
+                                       uint8_t *oq = q;
+                                       q = ppp_conf_nak(s, b, sizeof(b), PPPIPCP, &response, q, p, o, (uint8_t *) &addr, sizeof(addr));
+                                       if (!q || (q != oq && *response == ConfigRej))
+                                       {
+                                               sessionshutdown(s, "Can't negotiate IPCP.", CDN_ADMIN_DISC, TERM_USER_ERROR);
+                                               return;
+                                       }
+                               }
+
+                               break;
+
+                       case 129: // primary DNS
+                               if (o[1] != 6) return;
+
+                               addr = htonl(session[s].dns1);
+                               if (memcmp(o + 2, &addr, (sizeof addr)))
+                               {
+                                       q = ppp_conf_nak(s, b, sizeof(b), PPPIPCP, &response, q, p, o, (uint8_t *) &addr, sizeof(addr));
+                                       if (!q) return;
+                               }
+
+                               break;
+
+                       case 131: // secondary DNS
+                               if (o[1] != 6) return;
+
+                               addr = htonl(session[s].dns2);
+                               if (memcmp(o + 2, &addr, sizeof(addr)))
+                               {
+                                       q = ppp_conf_nak(s, b, sizeof(b), PPPIPCP, &response, q, p, o, (uint8_t *) &addr, sizeof(addr));
+                                       if (!q) return;
+                               }
+
+                               break;
+
+                       default:
+                               LOG(2, s, t, "    Rejecting PPP IPCP Option type %d\n", *o);
+                               q = ppp_conf_rej(s, b, sizeof(b), PPPIPCP, &response, q, p, o);
+                               if (!q) return;
+                       }
+
+                       length -= o[1];
+                       o += o[1];
+               }
+
+               if (response)
+               {
+                       l = q - response; // IPCP packet length
+                       *((uint16_t *) (response + 2)) = htons(l); // update header
+               }
+               else if (gotip)
+               {
+                       // Send packet back as ConfigAck
+                       response = makeppp(b, sizeof(b), p, l, s, t, PPPIPCP, 0, 0, 0);
+                       if (!response) return;
+                       *response = ConfigAck;
+               }
+               else
+               {
+                       LOG(1, s, t, "No IP in IPCP request\n");
+                       STAT(tunnel_rx_errors);
+                       return;
+               }
+
+               switch (session[s].ppp.ipcp)
+               {
+               case Closed:
+                       response = makeppp(b, sizeof(b), p, 2, s, t, PPPIPCP, 0, 0, 0);
+                       if (!response) return;
+                       *response = TerminateAck;
+                       *((uint16_t *) (response + 2)) = htons(l = 4);
+                       break;
+
+               case Stopped:
+                       initialise_restart_count(s, ipcp);
+                       sendipcp(s, t);
+                       if (*response == ConfigAck)
+                               change_state(s, ipcp, AckSent);
+                       else
+                               change_state(s, ipcp, RequestSent);
+
+                       break;
+
+               case RequestSent:
+                       if (*response == ConfigAck)
+                               change_state(s, ipcp, AckSent);
+
+                       break;
+
+               case AckReceived:
+                       if (*response == ConfigAck)
+                               ipcp_open(s, t);
+
+                       break;
+
+               case Opened:
+                       initialise_restart_count(s, ipcp);
+                       sendipcp(s, t);
+                       /* fallthrough */
+
+               case AckSent:
+                       if (*response == ConfigAck)
+                               change_state(s, ipcp, AckSent);
+                       else
+                               change_state(s, ipcp, RequestSent);
+
+                       break;
+
+               default:
+                       LOG(2, s, t, "IPCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.ipcp));
+                       return;
+               }
+
+               LOG(3, s, t, "IPCP: send %s\n", ppp_code(*response));
+               tunnelsend(b, l + (response - b), t);
+       }
+       else if (*p == TerminateReq)
+       {
+               switch (session[s].ppp.ipcp)
+               {
+               case Closed:
+               case Stopped:
+               case Closing:
+               case Stopping:
+               case RequestSent:
+               case AckReceived:
+               case AckSent:
+                       break;
+
+               case Opened:
+                       zero_restart_count(s, ipcp);
+                       change_state(s, ipcp, Closing);
+                       break;
+
+               default:
+                       LOG(2, s, t, "IPCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.ipcp));
+                       return;
+               }
+
+               *p = TerminateAck;      // send ack
+               q = makeppp(b, sizeof(b), p, l, s, t, PPPIPCP, 0, 0, 0);
+               if (!q) return;
+
+               LOG(3, s, t, "IPCP: send %s\n", ppp_code(*q));
+               tunnelsend(b, l + (q - b), t); // send it
+       }
+       else if (*p != CodeRej)
+       {
+               ppp_code_rej(s, t, PPPIPCP, "IPCP", p, l, b, sizeof(b));
+       }
+}
+
+static void ipv6cp_open(sessionidt s, tunnelidt t)
+{
+       LOG(3, s, t, "IPV6CP: Opened\n");
+
+       change_state(s, ipv6cp, Opened);
+       if (session[s].ipv6prefixlen)
+               route6set(s, session[s].ipv6route, session[s].ipv6prefixlen, 1);
+
+       // Send an initial RA (TODO: Should we send these regularly?)
+       send_ipv6_ra(s, t, NULL);
+}
+
+// Process IPV6CP messages
+void processipv6cp(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
+{
+       uint8_t b[MAXETHER];
+       uint8_t *q = 0;
+       uint16_t hl;
+
+       CSTAT(processipv6cp);
+
+       LOG_HEX(5, "IPV6CP", p, l);
+       if (l < 4)
+       {
+               LOG(1, s, t, "Short IPV6CP %d bytes\n", l);
+               STAT(tunnel_rx_errors);
+               return ;
+       }
+
+       if ((hl = ntohs(*(uint16_t *) (p + 2))) > l)
+       {
+               LOG(1, s, t, "Length mismatch IPV6CP %u/%u\n", hl, l);
+               STAT(tunnel_rx_errors);
+               return ;
+       }
+       l = hl;
+
+       if (session[s].ppp.phase < Network)
+       {
+               LOG(2, s, t, "IPV6CP %s ignored in %s phase\n", ppp_code(*p), ppp_phase(session[s].ppp.phase));
+               return;
+       }
+
+       LOG(3, s, t, "IPV6CP: recv %s\n", ppp_code(*p));
+
+       if (!session[s].ip)
+       {
+               LOG(3, s, t, "IPV6CP: no IPv4 address (IPCP in state %s)\n", ppp_state(session[s].ppp.ipcp));
+               return; // need IPCP to complete...
+       }
+
+       if (*p == ConfigAck)
+       {
+               switch (session[s].ppp.ipv6cp)
+               {
+               case RequestSent:
+                       initialise_restart_count(s, ipv6cp);
+                       change_state(s, ipv6cp, AckReceived);
+                       break;
+
+               case AckReceived:
+               case Opened:
+                       LOG(2, s, t, "IPV6CP: ConfigAck in state %s?  Sending ConfigReq\n", ppp_state(session[s].ppp.ipv6cp));
+                       sendipv6cp(s, t);
+                       change_state(s, ipv6cp, RequestSent);
+                       break;
+
+               case AckSent:
+                       ipv6cp_open(s, t);
+                       break;
+
+               default:
+                       LOG(2, s, t, "IPV6CP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.ipv6cp));
+               }
+       }
+       else if (*p == ConfigReq)
+       {
+               uint8_t *response = 0;
+               uint8_t *o = p + 4;
+               int length = l - 4;
+               int gotip = 0;
+               uint8_t ident[8];
+
+               while (length > 2)
+               {
+                       if (!o[1] || o[1] > length) return;
+
+                       switch (*o)
+                       {
+                       case 1: // interface identifier
+                               gotip++; // seen address
+                               if (o[1] != 10) return;
+
+                               *(uint32_t *) ident = htonl(session[s].ip);
+                               *(uint32_t *) (ident + 4) = 0;
+
+                               if (memcmp(o + 2, ident, sizeof(ident)))
+                               {
+                                       q = ppp_conf_nak(s, b, sizeof(b), PPPIPV6CP, &response, q, p, o, ident, sizeof(ident));
+                                       if (!q) return;
+                               }
+
+                               break;
+
+                       default:
+                               LOG(2, s, t, "    Rejecting PPP IPV6CP Option type %d\n", *o);
+                               q = ppp_conf_rej(s, b, sizeof(b), PPPIPV6CP, &response, q, p, o);
+                               if (!q) return;
+                       }
+
+                       length -= o[1];
+                       o += o[1];
+               }
+
+               if (response)
+               {
+                       l = q - response; // IPV6CP packet length
+                       *((uint16_t *) (response + 2)) = htons(l); // update header
+               }
+               else if (gotip)
+               {
+                       // Send packet back as ConfigAck
+                       response = makeppp(b, sizeof(b), p, l, s, t, PPPIPV6CP, 0, 0, 0);
+                       if (!response) return;
+                       *response = ConfigAck;
+               }
+               else
+               {
+                       LOG(1, s, t, "No interface identifier in IPV6CP request\n");
+                       STAT(tunnel_rx_errors);
+                       return;
+               }
+
+               switch (session[s].ppp.ipv6cp)
+               {
+               case Closed:
+                       response = makeppp(b, sizeof(b), p, 2, s, t, PPPIPV6CP, 0, 0, 0);
+                       if (!response) return;
+                       *response = TerminateAck;
+                       *((uint16_t *) (response + 2)) = htons(l = 4);
+                       break;
+
+               case Stopped:
+                       initialise_restart_count(s, ipv6cp);
+                       sendipv6cp(s, t);
+                       if (*response == ConfigAck)
+                               change_state(s, ipv6cp, AckSent);
+                       else
+                               change_state(s, ipv6cp, RequestSent);
+
+                       break;
+
+               case RequestSent:
+                       if (*response == ConfigAck)
+                               change_state(s, ipv6cp, AckSent);
+
+                       break;
+
+               case AckReceived:
+                       if (*response == ConfigAck)
+                               ipv6cp_open(s, t);
+
+                       break;
+
+               case Opened:
+                       initialise_restart_count(s, ipv6cp);
+                       sendipv6cp(s, t);
+                       /* fallthrough */
+
+               case AckSent:
+                       if (*response == ConfigAck)
+                               change_state(s, ipv6cp, AckSent);
+                       else
+                               change_state(s, ipv6cp, RequestSent);
+
+                       break;
+
+               default:
+                       LOG(2, s, t, "IPV6CP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.ipv6cp));
+                       return;
+               }
+
+               LOG(3, s, t, "IPV6CP: send %s\n", ppp_code(*response));
+               tunnelsend(b, l + (response - b), t);
+       }
+       else if (*p == TerminateReq)
+       {
+               switch (session[s].ppp.ipv6cp)
+               {
+               case Closed:
+               case Stopped:
+               case Closing:
+               case Stopping:
+               case RequestSent:
+               case AckReceived:
+               case AckSent:
+                       break;
+
+               case Opened:
+                       zero_restart_count(s, ipv6cp);
+                       change_state(s, ipv6cp, Closing);
+                       break;
+
+               default:
+                       LOG(2, s, t, "IPV6CP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.ipv6cp));
+                       return;
+               }
+
+               *p = TerminateAck;      // send ack
+               q = makeppp(b, sizeof(b),  p, l, s, t, PPPIPV6CP, 0, 0, 0);
+               if (!q) return;
+
+               LOG(3, s, t, "IPV6CP: send %s\n", ppp_code(*q));
+               tunnelsend(b, l + (q - b), t); // send it
+       }
+       else if (*p != CodeRej)
+       {
+               ppp_code_rej(s, t, PPPIPV6CP, "IPV6CP", p, l, b, sizeof(b));
+       }
+}
+
+// process IP packet received
+//
+// This MUST be called with at least 4 byte behind 'p'.
+// (i.e. this routine writes to p[-4]).
+void processipin(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
+{
+       in_addr_t ip;
+
+       CSTAT(processipin);
+
+       LOG_HEX(5, "IP", p, l);
+
+       if (l < 20)
+       {
+               LOG(1, s, t, "IP packet too short %d\n", l);
+               STAT(tunnel_rx_errors);
+               return ;
+       }
+
+       ip = ntohl(*(uint32_t *)(p + 12));
+
+       if (l > MAXETHER)
+       {
+               LOG(1, s, t, "IP packet too long %d\n", l);
+               STAT(tunnel_rx_errors);
+               return ;
+       }
+
+       if (session[s].ppp.phase != Network || session[s].ppp.ipcp != Opened)
+               return;
+
+       if (!session[s].bundle || bundle[session[s].bundle].num_of_links < 2) // FIXME: 
+       {
+               // no spoof (do sessionbyip to handled statically routed subnets)
+               if (ip != session[s].ip && sessionbyip(htonl(ip)) != s)
+               {
+                       LOG(4, s, t, "Dropping packet with spoofed IP %s\n", fmtaddr(htonl(ip), 0));
+                       return;
+               }
+       }
+
+       // run access-list if any
+       if (session[s].filter_in && !ip_filter(p, l, session[s].filter_in - 1))
+               return;
+
+       // adjust MSS on SYN and SYN,ACK packets with options
+       if ((ntohs(*(uint16_t *) (p + 6)) & 0x1fff) == 0 && p[9] == IPPROTO_TCP) // first tcp fragment
+       {
+               int ihl = (p[0] & 0xf) * 4; // length of IP header
+               if (l >= ihl + 20 && (p[ihl + 13] & TCP_FLAG_SYN) && ((p[ihl + 12] >> 4) > 5))
+                       adjust_tcp_mss(s, t, p, l, p + ihl);
+       }
+
+       // Add on the tun header
+       p -= 4;
+       *(uint32_t *) p = htonl(PKTIP);
+       l += 4;
+
+       // Are we throttled and a slave?
+       if (session[s].tbf_in && !config->cluster_iam_master) {
+               // Pass it to the master for handling.
+               master_throttle_packet(session[s].tbf_in, p, l);
+               return;
+       }
+
+       // Are we throttled and a master??
+       if (session[s].tbf_in && config->cluster_iam_master) {
+               // Actually handle the throttled packets.
+               tbf_queue_packet(session[s].tbf_in, p, l);
+               return;
+       }
+
+       // send to ethernet
+       if (tun_write(p, l) < 0)
+       {
+               STAT(tun_tx_errors);
+               LOG(0, s, t, "Error writing %d bytes to TUN device: %s (tunfd=%d, p=%p)\n",
+                       l, strerror(errno), tunfd, p);
+
+               return;
+       }
+
+       p += 4;
+       l -= 4;
+
+       if (session[s].snoop_ip && session[s].snoop_port)
+       {
+               // Snooping this session
+               snoop_send_packet(p, l, session[s].snoop_ip, session[s].snoop_port);
+       }
+
+       increment_counter(&session[s].cin, &session[s].cin_wrap, l);
+       session[s].cin_delta += l;
+       session[s].pin++;
+
+       sess_local[s].cin += l;
+       sess_local[s].pin++;
+
+       eth_tx += l;
+
+       STAT(tun_tx_packets);
+       INC_STAT(tun_tx_bytes, l);
+}
+
+// process Multilink PPP packet received
+void processmpin(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
+{
+       bundleidt b = session[s].bundle;
+       uint8_t begin_frame;
+       uint8_t end_frame;
+       uint32_t seq_num;
+       uint32_t offset;
+
+       if (!b)
+       {
+               LOG(3, s, t, "MPPP: Invalid bundle id: 0\n");
+               return;
+       }
+
+       begin_frame = (*p & 0x80);
+       end_frame = (*p & 0x40);
+       if (session[s].mssf)
+       {
+               // Get 12 bit for seq number
+               uint16_t short_seq_num = ntohs((*(uint16_t *) p) & 0xFF0F);
+               uint16_t short_seq_num2 = short_seq_num >> 4;
+               p += 2;
+               l -= 2;
+               seq_num = short_seq_num2;
+               // After this point the pointer should be advanced 2 bytes
+               LOG(3, s, t, "MPPP: 12 bits, sequence number: %d, short1: %d, short2: %d\n",seq_num, short_seq_num, short_seq_num2);
+       }
+       else
+       {
+               // Get 24 bit for seq number
+               p++;
+               seq_num = ntohl((*(uint32_t *) p) & 0xFFFFFF00);
+               seq_num = seq_num >> 8;
+               p += 3;
+               l -= 4;
+               // After this point the pointer should be advanced 4 bytes
+               LOG(4, s, t, "MPPP: 24 bits sequence number:%d\n",seq_num);
+       }
+
+       if (seq_num - bundle[b].offset < 0)
+       {
+               bundle[b].offset = 0;
+               bundle[b].pending_frag = 0;
+       }
+
+       offset = bundle[b].offset;
+       if (begin_frame)
+       {
+               // Check for previous non-assembled frames
+               int error = 0;
+               if (bundle[b].pending_frag)
+               {
+                       uint32_t fn = bundle[b].seq_num_m - offset;
+                       uint16_t cur_len;
+                       bundle[b].pending_frag = 0;
+                       // Check for array indexes
+                       if (fn < 0 || fn > MAXFRAGNUM)
+                       {
+                               LOG(2, s, t, "ERROR: Index out of range fn:%d, bundle:%d\n",fn,b);
+                               return;
                        }
-                       else
+
+                       if (seq_num-offset < 0 || seq_num-offset > MAXFRAGNUM)
+                       {
+                               LOG(2, s, t, "ERROR: Index out of range fn(last):%d, bundle:%d\n",fn,b);
+                               return;
+                       }
+                       /////////////////////////////////////////////////////
+                       cur_len = 4;   // This is set to 4 to leave 4 bytes for function processipin
+                       for (fn = bundle[b].seq_num_m - offset; fn < seq_num - offset; fn++)
+                       {
+                               if (!frag[b].fragment[fn].length)
+                               {
+                                       LOG(4, s, t, "MPPP: Found lost fragment while reassembling frame %d in (%d,%d)\n",fn, bundle[b].seq_num_m-offset, seq_num-offset);
+                                       error = 1;
+                                       break;
+                               }
+
+                               if (cur_len + frag[b].fragment[fn].length > MAXETHER)
+                               {
+                                       LOG(2, s, t, "MPPP: ERROR: very long frame after assembling %d\n", frag[b].fragment[fn].length+cur_len);
+                                       error = 1;
+                                       break;
+                               }
+
+                               memcpy(frag[b].reassembled_frame+cur_len, frag[b].fragment[fn].data, frag[b].fragment[fn].length);
+                               cur_len += frag[b].fragment[fn].length; 
+                               frag[b].fragment[fn].length = 0;      // Indicates that this fragment has been consumed
+                               // This is usefull for compression
+                               memset(frag[b].fragment[fn].data, 0, sizeof(frag[b].fragment[fn].data));
+                       }
+
+                       if (!error)
+                       {
+                               frag[b].re_frame_len = cur_len;
+                               // Process the resassembled frame
+                               LOG(4, s, t, "MPPP: Process the reassembled frame, len=%d\n",cur_len);
+                               processmpframe(s, t, frag[b].reassembled_frame, frag[b].re_frame_len, 1);
+                               // Set reassembled frame length to zero after processing it
+                               frag[b].re_frame_len = 0;
+                               memset(frag[b].reassembled_frame, 0, sizeof(frag[b].reassembled_frame));
+                       }
+               }
+               //////////////////////////////////////////
+               bundle[b].seq_num_m = seq_num;
+               if (end_frame)
+               {
+                       // Both bits are set
+                       LOG(4, s, t, "MPPP: Both bits are set (Begin and End).\n");
+                       processmpframe(s, t, p, l, 0);
+                       // The maximum number of fragments is 1500
+                       if (seq_num - bundle[b].offset >= 1400)
                        {
-                               *p = ConfigRej;        // reject
+                               bundle[b].offset = seq_num;
+                               LOG(4, s, t, "MPPP: Setting offset to: %d\n",bundle[b].offset);
                        }
                }
                else
-                       *p = TerminateAck;     // close
-               q = makeppp(b, p, l, t, s, PPPCCP);
-               tunnelsend(b, l + (q - b), t); // send it
+               {
+                       bundle[b].pending_frag = 1;
+                       // End bit is clear
+                       LOG(4, s, t, "MPPP: Push to receive buffer\n");
+                       // Push to the receive buffer
+                       // Array indexes checking
+                       if (seq_num-offset < 0 || seq_num-offset >= MAXFRAGNUM)
+                       {
+                               LOG(2, s, t, "ERROR: Index out of range, push to receive buffer(1) seq:%d, offset:%d, bundle:%d\n",seq_num,offset,b);
+                               return;
+                       }
+                       // Perform length checking
+                       if (l > MAXFRAGLEN)
+                       {
+                               LOG(2, s, t, "MPPP: ERROR: very long fragment length (1)\n");
+                               return;
+                       }
+                       frag[b].fragment[seq_num - offset].length = l;
+                       memcpy(frag[b].fragment[seq_num - offset].data, p, l);
+               }
+       }
+       else
+       {
+               LOG(4, s, t, "MPPP: Push to receive buffer\n");
+               // Push to the receive buffer
+               // Array indexes checking
+               if (seq_num-offset < 0 || seq_num-offset >= MAXFRAGNUM)
+               {
+                       LOG(2, s, t, "ERROR: Index out of range, push to receive buffer(2) seq:%d, offset:%d, bundle:%d\n",seq_num,offset,b);
+                       return;
+               }
+               // Perform length checking
+               if (l > MAXFRAGLEN)
+               {
+                       LOG(2, s, t, "MPPP: ERROR: very long fragment length (2).\n");
+                       return;
+               }
+               frag[b].fragment[seq_num - offset].length = l;
+               memcpy(frag[b].fragment[seq_num - offset].data, p, l);
        }
 }
 
-// send a CHAP PP packet
-void sendchap(tunnelidt t, sessionidt s)
+// process IPv6 packet received
+//
+// This MUST be called with at least 4 byte behind 'p'.
+// (i.e. this routine writes to p[-4]).
+void processipv6in(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
 {
-       u8 b[MAXCONTROL];
-       u8 r = session[s].radius;
-       u8 *q;
-#ifdef STAT_CALLS
-       STAT(call_sendchap);
-#endif
-       if (!r)
+       struct in6_addr ip;
+       in_addr_t ipv4;
+
+       CSTAT(processipv6in);
+
+       LOG_HEX(5, "IPv6", p, l);
+
+       ip = *(struct in6_addr *) (p + 8);
+       ipv4 = ntohl(*(uint32_t *)(p + 16));
+
+       if (l > MAXETHER)
        {
-               log(1, 0, s, t, "No RADIUS to send challenge\n");
-               STAT(tunnel_tx_errors);
+               LOG(1, s, t, "IP packet too long %d\n", l);
+               STAT(tunnel_rx_errors);
                return ;
        }
-       log(1, 0, s, t, "Send CHAP challenge\n");
-       {                            // new challenge
-               int n;
-               for (n = 0; n < 15; n++)
-                       radius[r].auth[n] = rand();
+
+       if (session[s].ppp.phase != Network || session[s].ppp.ipv6cp != Opened)
+               return;
+
+       // no spoof
+       if (ipv4 != session[s].ip && memcmp(&config->ipv6_prefix, &ip, 8) && sessionbyipv6(ip) != s)
+       {
+               char str[INET6_ADDRSTRLEN];
+               LOG(5, s, t, "Dropping packet with spoofed IP %s\n",
+                               inet_ntop(AF_INET6, &ip, str, INET6_ADDRSTRLEN));
+               return;
+       }
+
+       // Check if it's a Router Solicition message.
+       if (*(p + 6) == 58 && *(p + 7) == 255 && *(p + 24) == 0xFF && *(p + 25) == 2 &&
+                       *(uint32_t *)(p + 26) == 0 && *(uint32_t *)(p + 30) == 0 &&
+                       *(uint32_t *)(p + 34) == 0 &&
+                       *(p + 38) == 0 && *(p + 39) == 2 && *(p + 40) == 133) {
+               LOG(3, s, t, "Got IPv6 RS\n");
+               send_ipv6_ra(s, t, &ip);
+               return;
+       }
+
+       // Add on the tun header
+       p -= 4;
+       *(uint32_t *) p = htonl(PKTIPV6);
+       l += 4;
+
+       // Are we throttled and a slave?
+       if (session[s].tbf_in && !config->cluster_iam_master) {
+               // Pass it to the master for handling.
+               master_throttle_packet(session[s].tbf_in, p, l);
+               return;
+       }
+
+       // Are we throttled and a master??
+       if (session[s].tbf_in && config->cluster_iam_master) {
+               // Actually handle the throttled packets.
+               tbf_queue_packet(session[s].tbf_in, p, l);
+               return;
+       }
+
+       // send to ethernet
+       if (tun_write(p, l) < 0)
+       {
+               STAT(tun_tx_errors);
+               LOG(0, s, t, "Error writing %d bytes to TUN device: %s (tunfd=%d, p=%p)\n",
+                       l, strerror(errno), tunfd, p);
+
+               return;
+       }
+
+       p += 4;
+       l -= 4;
+
+       if (session[s].snoop_ip && session[s].snoop_port)
+       {
+               // Snooping this session
+               snoop_send_packet(p, l, session[s].snoop_ip, session[s].snoop_port);
+       }
+
+       increment_counter(&session[s].cin, &session[s].cin_wrap, l);
+       session[s].cin_delta += l;
+       session[s].pin++;
+
+       sess_local[s].cin += l;
+       sess_local[s].pin++;
+
+       eth_tx += l;
+
+       STAT(tun_tx_packets);
+       INC_STAT(tun_tx_bytes, l);
+}
+
+//
+// Helper routine for the TBF filters.
+// Used to send queued data in from the user.
+//
+void send_ipin(sessionidt s, uint8_t *buf, int len)
+{
+       LOG_HEX(5, "IP in throttled", buf, len);
+
+       if (write(tunfd, buf, len) < 0)
+       {
+               STAT(tun_tx_errors);
+               LOG(0, 0, 0, "Error writing %d bytes to TUN device: %s (tunfd=%d, p=%p)\n",
+                       len, strerror(errno), tunfd, buf);
+
+               return;
+       }
+
+       buf += 4;
+       len -= 4;
+
+       if (session[s].snoop_ip && session[s].snoop_port)
+       {
+               // Snooping this session
+               snoop_send_packet(buf, len, session[s].snoop_ip, session[s].snoop_port);
+       }
+
+       // Increment packet counters
+       increment_counter(&session[s].cin, &session[s].cin_wrap, len);
+       session[s].cin_delta += len;
+       session[s].pin++;
+
+       sess_local[s].cin += len;
+       sess_local[s].pin++;
+
+       eth_tx += len;
+
+       STAT(tun_tx_packets);
+       INC_STAT(tun_tx_bytes, len - 4);
+}
+
+
+// Process CCP messages
+void processccp(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
+{
+       uint8_t b[MAXETHER];
+       uint8_t *q;
+
+       CSTAT(processccp);
+
+       LOG_HEX(5, "CCP", p, l);
+
+       if (session[s].ppp.phase < Network)
+       {
+               LOG(2, s, t, "CCP %s ignored in %s phase\n", ppp_code(*p), ppp_phase(session[s].ppp.phase));
+               return;
+       }
+
+       if (l < 1)
+       {
+               LOG(1, s, t, "Short CCP packet\n");
+               STAT(tunnel_rx_errors);
+       }
+
+       LOG(4, s, t, "CCP: recv %s\n", ppp_code(*p));
+       if (*p == ConfigAck)
+       {
+               switch (session[s].ppp.ccp)
+               {
+               case RequestSent:
+                       initialise_restart_count(s, ccp);
+                       change_state(s, ccp, AckReceived);
+                       break;
+
+               case AckReceived:
+               case Opened:
+                       LOG(2, s, t, "CCP: ConfigAck in state %s?  Sending ConfigReq\n", ppp_state(session[s].ppp.ccp));
+                       sendccp(s, t);
+                       change_state(s, ccp, RequestSent);
+                       break;
+
+               case AckSent:
+                       LOG(3, s, t, "CCP: Opened\n");
+                       change_state(s, ccp, Opened);
+                       break;
+
+               default:
+                       LOG(2, s, t, "CCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.ccp));
+               }
+       }
+       else if (*p == ConfigReq)
+       {
+               if (l < 6) // accept no compression
+                       *p = ConfigAck;
+               else // compression requested--reject
+                       *p = ConfigRej;
+
+               q = makeppp(b, sizeof(b), p, l, s, t, PPPCCP, 0, 0, 0);
+               if (!q) return;
+
+               switch (session[s].ppp.ccp)
+               {
+               case Closed:
+                       q = makeppp(b, sizeof(b), p, 2, s, t, PPPCCP, 0, 0, 0);
+                       if (!q) return;
+                       *q = TerminateAck;
+                       *((uint16_t *) (q + 2)) = htons(l = 4);
+                       break;
+
+               case Stopped:
+                       initialise_restart_count(s, ccp);
+                       sendccp(s, t);
+                       if (*q == ConfigAck)
+                               change_state(s, ccp, AckSent);
+                       else
+                               change_state(s, ccp, RequestSent);
+
+                       break;
+
+               case RequestSent:
+                       if (*q == ConfigAck)
+                               change_state(s, ccp, AckSent);
+
+                       break;
+
+               case AckReceived:
+                       if (*q == ConfigAck)
+                               change_state(s, ccp, Opened);
+
+                       break;
+
+               case Opened:
+                       initialise_restart_count(s, ccp);
+                       sendccp(s, t);
+                       /* fallthrough */
+
+               case AckSent:
+                       if (*q == ConfigAck)
+                               change_state(s, ccp, AckSent);
+                       else
+                               change_state(s, ccp, RequestSent);
+
+                       break;
+
+               default:
+                       LOG(2, s, t, "CCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.ccp));
+                       return;
+               }
+
+               LOG(4, s, t, "CCP: send %s\n", ppp_code(*q));
+               tunnelsend(b, l + (q - b), t);
+       }
+       else if (*p == TerminateReq)
+       {
+               *p = TerminateAck;
+               q = makeppp(b, sizeof(b),  p, l, s, t, PPPCCP, 0, 0, 0);
+               if (!q) return;
+               LOG(3, s, t, "CCP: send %s\n", ppp_code(*q));
+               tunnelsend(b, l + (q - b), t);
+               change_state(s, ccp, Stopped);
+       }
+       else if (*p != CodeRej)
+       {
+               ppp_code_rej(s, t, PPPCCP, "CCP", p, l, b, sizeof(b));
+       }
+}
+
+// send a CHAP challenge
+void sendchap(sessionidt s, tunnelidt t)
+{
+       uint8_t b[MAXETHER];
+       uint16_t r;
+       uint8_t *q;
+
+       CSTAT(sendchap);
+
+       r = radiusnew(s);
+       if (!r)
+       {
+               LOG(1, s, t, "No RADIUS to send challenge\n");
+               STAT(tunnel_tx_errors);
+               return;
        }
-       radius[r].chap = 1;          // CHAP not PAP
+
+       LOG(1, s, t, "Send CHAP challenge\n");
+
+       radius[r].chap = 1;             // CHAP not PAP
        radius[r].id++;
        if (radius[r].state != RADIUSCHAP)
                radius[r].try = 0;
+
        radius[r].state = RADIUSCHAP;
        radius[r].retry = backoff(radius[r].try++);
        if (radius[r].try > 5)
        {
-               sessionshutdown(s, "Timeout CHAP");
+               sessionshutdown(s, "CHAP timeout.", CDN_ADMIN_DISC, TERM_REAUTHENTICATION_FAILURE);
                STAT(tunnel_tx_errors);
                return ;
        }
-       q = makeppp(b, 0, 0, t, s, PPPCHAP);
-       *q = 1;                      // challenhe
-       q[1] = radius[r].id;         // ID
-       q[4] = 16;                   // length
-       memcpy(q + 5, radius[r].auth, 16); // challenge
-       strcpy(q + 21, hostname);    // our name
-       *(u16 *) (q + 2) = htons(strlen(hostname) + 21); // length
+       q = makeppp(b, sizeof(b), 0, 0, s, t, PPPCHAP, 0, 0, 0);
+       if (!q) return;
+
+       *q = 1;                                 // challenge
+       q[1] = radius[r].id;                    // ID
+       q[4] = 16;                              // value size (size of challenge)
+       memcpy(q + 5, radius[r].auth, 16);      // challenge
+       strcpy((char *) q + 21, hostname);      // our name
+       *(uint16_t *) (q + 2) = htons(strlen(hostname) + 21); // length
        tunnelsend(b, strlen(hostname) + 21 + (q - b), t); // send it
 }
 
 // fill in a L2TP message with a PPP frame,
-// copies existing PPP message and changes magic number if seen
 // returns start of PPP frame
-u8 *makeppp(u8 * b, u8 * p, int l, tunnelidt t, sessionidt s, u16 mtype)
+uint8_t *makeppp(uint8_t *b, int size, uint8_t *p, int l, sessionidt s, tunnelidt t, uint16_t mtype, uint8_t prio, bundleidt bid, uint8_t mp_bits)
 {
-       *(u16 *) (b + 0) = htons(0x0002); // L2TP with no options
-       *(u16 *) (b + 2) = htons(tunnel[t].far); // tunnel
-       *(u16 *) (b + 4) = htons(session[s].far); // session
+       uint16_t hdr = 0x0002; // L2TP with no options
+       uint16_t type = mtype;
+       uint8_t *start = b;
+
+       if (size < 16) // Need more space than this!!
+       {
+               LOG(0, s, t, "makeppp buffer too small for L2TP header (size=%d)\n", size);
+               return NULL;
+       }
+
+       if (prio) hdr |= 0x0100; // set priority bit
+
+       *(uint16_t *) (b + 0) = htons(hdr);
+       *(uint16_t *) (b + 2) = htons(tunnel[t].far); // tunnel
+       *(uint16_t *) (b + 4) = htons(session[s].far); // session
        b += 6;
-       if (mtype != PPPLCP && !(session[s].flags & SESSIONACFC))
+
+       // Check whether this session is part of multilink
+       if (bid)
+       {
+               if (bundle[bid].num_of_links > 1)
+                       type = PPPMP; // Change PPP message type to the PPPMP
+               else
+                       bid = 0;
+       }
+
+       if (type == PPPLCP || !(session[s].flags & SESSION_ACFC))
        {
-               *(u16 *) b = htons(0xFF03); // HDLC header
+               *(uint16_t *) b = htons(0xFF03); // HDLC header
                b += 2;
        }
-       if (mtype < 0x100 && session[s].flags & SESSIONPFC)
-               *b++ = mtype;
+
+       if (type < 0x100 && session[s].flags & SESSION_PFC)
+       {
+               *b++ = type;
+       }
        else
        {
-               *(u16 *) b = htons(mtype);
+               *(uint16_t *) b = htons(type);
                b += 2;
        }
+
+       if (bid)
+       {
+               // Set the sequence number and (B)egin (E)nd flags
+               if (session[s].mssf)
+               {
+                       // Set the multilink bits
+                       uint16_t bits_send = mp_bits;
+                       *(uint16_t *) b = htons((bundle[bid].seq_num_t & 0xFF0F)|bits_send);
+                       b += 2;
+               }
+               else
+               {
+                       *(uint32_t *) b = htonl(bundle[bid].seq_num_t);
+                       // Set the multilink bits
+                       *b = mp_bits;
+                       b += 4;
+               }
+
+               bundle[bid].seq_num_t++;
+
+               // Add the message type if this fragment has the begin bit set
+               if (mp_bits & MP_BEGIN)
+               {
+                       //*b++ = mtype; // The next two lines are instead of this 
+                       *(uint16_t *) b = htons(mtype); // Message type
+                       b += 2;
+               }
+       }
+
+       if ((b - start) + l > size)
+       {
+               LOG(2, s, t, "makeppp would overflow buffer (size=%d, header+payload=%d)\n", size, (b - start) + l);
+               return NULL;
+       }
+
+       // Copy the payload
        if (p && l)
                memcpy(b, p, l);
+
        return b;
 }
 
-// find a PPP option, returns point to option, or 0 if not found
-u8 *findppp(u8 * b, u8 mtype)
+static int add_lcp_auth(uint8_t *b, int size, int authtype)
 {
-       u16 l = ntohs(*(u16 *) (b + 2));
-       if (l < 4)
+       int len = 0;
+       if ((authtype == AUTHCHAP && size < 5) || size < 4)
                return 0;
-       b += 4;
-       l -= 4;
-       while (l)
+
+       *b++ = 3; // Authentication-Protocol
+       if (authtype == AUTHCHAP)
        {
-               if (l < b[1] || !b[1])
-                       return 0;            // faulty
-               if (*b == mtype)
-                       return b;
-               l -= b[1];
-               b += b[1];
+               len = *b++ = 5; // length
+               *(uint16_t *) b = htons(PPPCHAP); b += 2;
+               *b++ = 5; // MD5
        }
-       return 0;
+       else if (authtype == AUTHPAP)
+       {
+               len = *b++ = 4; // length
+               *(uint16_t *) b = htons(PPPPAP); b += 2;
+       }
+       else
+       {
+               LOG(0, 0, 0, "add_lcp_auth called with unsupported auth type %d\n", authtype);
+       }
+
+       return len;
+}
+
+// Send LCP ConfigReq for MRU, authentication type and magic no
+void sendlcp(sessionidt s, tunnelidt t)
+{
+       uint8_t b[500], *q, *l;
+       int authtype = sess_local[s].lcp_authtype;
+
+        if (!(q = makeppp(b, sizeof(b), NULL, 0, s, t, PPPLCP, 0, 0, 0)))
+               return;
+
+        LOG(3, s, t, "LCP: send ConfigReq%s%s%s including MP options\n",
+           authtype ? " (" : "",
+           authtype ? (authtype == AUTHCHAP ? "CHAP" : "PAP") : "",
+           authtype ? ")" : "");
+
+       l = q;
+       *l++ = ConfigReq;
+       *l++ = ++sess_local[s].lcp_ident; // ID
+
+       l += 2; //Save space for length
+
+       if (sess_local[s].ppp_mru)
+       {
+               *l++ = 1; *l++ = 4; // Maximum-Receive-Unit (length 4)
+               *(uint16_t *) l = htons(sess_local[s].ppp_mru); l += 2;
+       }
+
+       if (authtype)
+               l += add_lcp_auth(l, sizeof(b) - (l - b), authtype);
+
+       if (session[s].magic)
+       {
+               *l++ = 5; *l++ = 6; // Magic-Number (length 6)
+               *(uint32_t *) l = htonl(session[s].magic);
+               l += 4;
+       }
+
+        if (sess_local[s].mp_mrru)
+        {
+               *l++ = 17; *l++ = 4; // Multilink Max-Receive-Reconstructed-Unit (length 4)
+               *(uint16_t *) l = htons(sess_local[s].mp_mrru); l += 2;
+       }
+
+        if (sess_local[s].mp_epdis)
+        {
+               *l++ = 19; *l++ = 7;    // Multilink Endpoint Discriminator (length 7)
+               *l++ = IPADDR;  // Endpoint Discriminator class
+               *(uint32_t *) l = htonl(sess_local[s].mp_epdis);
+               l += 4;
+       }
+
+       *(uint16_t *)(q + 2) = htons(l - q); // Length
+
+       LOG_HEX(5, "PPPLCP", q, l - q);
+       if (config->debug > 3) dumplcp(q, l - q);
+
+       tunnelsend(b, (l - b), t);
+       restart_timer(s, lcp);
 }
 
-// Send initial LCP ConfigReq
-void initlcp(tunnelidt t, sessionidt s)
+// Send CCP request for no compression
+void sendccp(sessionidt s, tunnelidt t)
 {
-       char b[500] = {0}, *q;
+       uint8_t b[500], *q;
+
+       if (!(q = makeppp(b, sizeof(b), NULL, 0, s, t, PPPCCP, 0, 0, 0)))
+               return;
+
+       LOG(3, s, t, "CCP: send ConfigReq (no compression)\n");
 
-       q = makeppp(b, NULL, 0, t, s, PPPLCP);
-       log(4, 0, s, t, "Sending LCP ConfigReq for PAP\n");
        *q = ConfigReq;
-       *(u8 *)(q + 1) = (time_now % 255) + 1; // ID
-       *(u16 *)(q + 2) = htons(8); // Length
-       *(u8 *)(q + 4) = 3;
-       *(u8 *)(q + 5) = 4;
-       *(u16 *)(q + 6) = htons(0xC023); // PAP
-       tunnelsend(b, 12 + 8, t);
+       *(q + 1) = ++sess_local[s].lcp_ident; // ID
+       *(uint16_t *)(q + 2) = htons(4); // Length
+
+       LOG_HEX(5, "PPPCCP", q, 4);
+       tunnelsend(b, (q - b) + 4 , t);
+       restart_timer(s, ccp);
 }
 
+// Reject unknown/unconfigured protocols
+void protoreject(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l, uint16_t proto)
+{
+
+       uint8_t buf[MAXETHER];
+       uint8_t *q;
+       int mru = session[s].mru;
+       if (mru < MINMTU) mru = MINMTU;
+       if (mru > sizeof(buf)) mru = sizeof(buf);
+
+       l += 6;
+       if (l > mru) l = mru;
+
+       q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPLCP, 0, 0, 0);
+       if (!q) return;
+
+       *q = ProtocolRej;
+       *(q + 1) = ++sess_local[s].lcp_ident;
+       *(uint16_t *)(q + 2) = htons(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);
+}