Fix: MLPPP complete lost frame.

[l2tpns.git] / ppp.c

diff --git a/ppp.c b/ppp.c
index a1ad56a..e805e22 100644 (file)
--- a/ppp.c
+++ b/ppp.c
@@ -1,7 +1,5 @@
 // L2TPNS PPP Stuff
 
 // L2TPNS PPP Stuff
 

-char const *cvs_id_ppp = "$Id: ppp.c,v 1.102 2006-08-02 13:35:39 bodea Exp $";
-

 #include <stdio.h>
 #include <string.h>
 #include <unistd.h>
 #include <stdio.h>
 #include <string.h>
 #include <unistd.h>


@@ -31,6 +29,16 @@ static int epdiscmp(epdist, epdist);
 static void setepdis(epdist *, epdist);
 static void ipcp_open(sessionidt s, tunnelidt t);
 
 static void setepdis(epdist *, epdist);
 static void ipcp_open(sessionidt s, tunnelidt t);
 

+static int first_session_in_bundle(sessionidt s)
+{
+       bundleidt i;
+       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))
+                               return 0;
+       return 1;       
+}
+

 // Process PAP messages
 void processpap(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
 {
 // Process PAP messages
 void processpap(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
 {


@@ -140,7 +148,10 @@ void processpap(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
 
                radius[r].id = p[1];
                LOG(3, s, t, "Sending login for %s/%s to RADIUS\n", user, pass);
 
                radius[r].id = p[1];
                LOG(3, s, t, "Sending login for %s/%s to RADIUS\n", user, pass);

-               radiussend(r, RADIUSAUTH);
+               if ((session[s].mrru) && (!first_session_in_bundle(s)))
+                       radiussend(r, RADIUSJUSTAUTH);
+               else
+                       radiussend(r, RADIUSAUTH);

        }
 }
 
        }
 }
 


@@ -257,7 +268,10 @@ void processchap(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
 
        radius[r].chap = 1;
        LOG(3, s, t, "CHAP login %s\n", session[s].user);
 
        radius[r].chap = 1;
        LOG(3, s, t, "CHAP login %s\n", session[s].user);

-       radiussend(r, RADIUSAUTH);
+       if ((session[s].mrru) && (!first_session_in_bundle(s)))
+               radiussend(r, RADIUSJUSTAUTH);
+       else
+               radiussend(r, RADIUSAUTH);

 }
 
 static void dumplcp(uint8_t *p, int l)
 }
 
 static void dumplcp(uint8_t *p, int l)


@@ -366,17 +380,7 @@ void lcp_open(sessionidt s, tunnelidt t)
        }
        else
        {
        }
        else
        {

-               if (session[s].bundle && bundle[session[s].bundle].num_of_links > 1)
-               {
-                       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].session_timeout = session[first_ses].session_timeout;
-                       ipcp_open(s, t);
-               }
-               else
+               if(session[s].bundle == 0 || bundle[session[s].bundle].num_of_links == 1)

                {
                        // This-Layer-Up
                        sendipcp(s, t);
                {
                        // This-Layer-Up
                        sendipcp(s, t);


@@ -389,6 +393,12 @@ void lcp_open(sessionidt s, tunnelidt t)
 
                        change_state(s, ccp, Stopped);
                }
 
                        change_state(s, ccp, Stopped);
                }

+               else
+               {
+                       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);
+                       ipcp_open(s, t);
+                }

        }
 }
 
        }
 }
 


@@ -809,6 +819,10 @@ void processlcp(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
 
                        break;
 
 
                        break;
 

+               case Closing:
+                       sessionshutdown(s, "LCP: ConfigReq in state Closing. This should not happen. Killing session.", CDN_ADMIN_DISC, TERM_LOST_SERVICE);
+                       break;
+

                default:
                        LOG(2, s, t, "LCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.lcp));
                        return;
                default:
                        LOG(2, s, t, "LCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.lcp));
                        return;


@@ -1091,10 +1105,20 @@ int join_bundle(sessionidt s)
                {
                        if (epdiscmp(session[s].epdis,bundle[i].epdis) && !strcmp(session[s].user, bundle[i].user))
                        {
                {
                        if (epdiscmp(session[s].epdis,bundle[i].epdis) && !strcmp(session[s].user, bundle[i].user))
                        {

+                               sessionidt first_ses = bundle[i].members[0];
+                               if (bundle[i].mssf != session[s].mssf)
+                               {
+                                       // uniformity of sequence number format must be insured
+                                       LOG(3, s, session[s].tunnel, "MPPP: unable to bundle session %d in bundle %d cause of different mssf\n", s, i);
+                                       return -1;
+                               }

                                session[s].bundle = i;
                                session[s].bundle = i;

-                               bundle[i].mrru = session[s].mrru;
-                               bundle[i].mssf = session[s].mssf;
-                               if (session[s].epdis.length > 0)
+                               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;
+
+                               if(session[s].epdis.length > 0)

                                        setepdis(&bundle[i].epdis, session[s].epdis);
 
                                strcpy(bundle[i].user, session[s].user);
                                        setepdis(&bundle[i].epdis, session[s].epdis);
 
                                strcpy(bundle[i].user, session[s].user);


@@ -1112,11 +1136,19 @@ int join_bundle(sessionidt s)
        session[s].bundle = b;
        bundle[b].mrru = session[s].mrru;
        bundle[b].mssf = session[s].mssf;
        session[s].bundle = b;
        bundle[b].mrru = session[s].mrru;
        bundle[b].mssf = session[s].mssf;

-       if (session[s].epdis.length > 0)
+       // FIXME !!! to enable l2tpns reading mssf frames receiver_max_seq, sender_max_seq must be introduce
+       // now session[s].mssf flag indecates that the receiver wish to receive frames in mssf, so max_seq (i.e. recv_max_seq) = 1<<24
+       /*
+       if (bundle[b].mssf)
+               bundle[b].max_seq = 1 << 12;
+       else */
+               bundle[b].max_seq = 1 << 24;
+       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;
                setepdis(&bundle[b].epdis, session[s].epdis);
 
        strcpy(bundle[b].user, session[s].user);
        bundle[b].members[0] = s;

+       bundle[b].timeout = session[s].timeout;

        LOG(3, s, session[s].tunnel, "MPPP: Created a new bundle (%d)\n", b);
        return b;
 }
        LOG(3, s, session[s].tunnel, "MPPP: Created a new bundle (%d)\n", b);
        return b;
 }


@@ -1148,23 +1180,24 @@ static void setepdis(epdist *ep1, epdist ep2)
 
 static bundleidt new_bundle()
 {
 
 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;
+        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
+                       memset(&frag[i], 0, sizeof(fragmentationt));
+                        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)
 }
 
 static void ipcp_open(sessionidt s, tunnelidt t)


@@ -1505,7 +1538,7 @@ void processipv6cp(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
                uint8_t *o = p + 4;
                int length = l - 4;
                int gotip = 0;
                uint8_t *o = p + 4;
                int length = l - 4;
                int gotip = 0;

-               uint8_t ident[8];
+               uint32_t ident[2];

 
                while (length > 2)
                {
 
                while (length > 2)
                {


@@ -1517,12 +1550,12 @@ void processipv6cp(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
                                gotip++; // seen address
                                if (o[1] != 10) return;
 
                                gotip++; // seen address
                                if (o[1] != 10) return;
 

-                               *(uint32_t *) ident = htonl(session[s].ip);
-                               *(uint32_t *) (ident + 4) = 0;
+                               ident[0] = htonl(session[s].ip);
+                               ident[1] = 0;

 
                                if (memcmp(o + 2, ident, sizeof(ident)))
                                {
 
                                if (memcmp(o + 2, ident, sizeof(ident)))
                                {

-                                       q = ppp_conf_nak(s, b, sizeof(b), PPPIPV6CP, &response, q, p, o, ident, sizeof(ident));
+                                       q = ppp_conf_nak(s, b, sizeof(b), PPPIPV6CP, &response, q, p, o, (uint8_t *)ident, sizeof(ident));

                                        if (!q) return;
                                }
 
                                        if (!q) return;
                                }
 


@@ -1645,6 +1678,39 @@ void processipv6cp(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
        }
 }
 
        }
 }
 

+static void update_sessions_in_stat(sessionidt s, uint16_t l)
+{
+       bundleidt b = session[s].bundle;
+       if (!b)
+       {
+               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++;
+       }
+       else
+       {
+               int i = frag[b].re_frame_begin_index;
+               int end = frag[b].re_frame_end_index;
+               for (;;)
+               {
+                       l = frag[b].fragment[i].length;
+                       s = frag[b].fragment[i].sid;
+                       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++;
+                       if (i == end)
+                               return;
+                       i = (i + 1) & MAXFRAGNUM_MASK;
+               }
+       }
+}
+

 // process IP packet received
 //
 // This MUST be called with at least 4 byte behind 'p'.
 // process IP packet received
 //
 // This MUST be called with at least 4 byte behind 'p'.


@@ -1703,17 +1769,13 @@ void processipin(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
        *(uint32_t *) p = htonl(PKTIP);
        l += 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);
+       if (session[s].tbf_in)
+       {
+               // Are we throttling this session?
+               if (config->cluster_iam_master)
+                       tbf_queue_packet(session[s].tbf_in, p, l);
+               else
+                       master_throttle_packet(session[s].tbf_in, p, l);

                return;
        }
 
                return;
        }
 


@@ -1736,12 +1798,7 @@ void processipin(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
                snoop_send_packet(p, l, session[s].snoop_ip, session[s].snoop_port);
        }
 
                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++;
+       update_sessions_in_stat(s, l);

 
        eth_tx += l;
 
 
        eth_tx += l;
 


@@ -1753,161 +1810,376 @@ void processipin(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
 void processmpin(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
 {
        bundleidt b = session[s].bundle;
 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;
+       bundlet * this_bundle = &bundle[b];
+       uint32_t maskSeq, max_seq;
+       int frag_offset;
+       uint16_t frag_index, frag_index_next, frag_index_prev;
+       fragmentationt *this_fragmentation = &frag[b];
+       uint8_t begin_frame = (*p & MP_BEGIN);
+       uint8_t end_frame = (*p & MP_END);
+       uint32_t seq_num, seq_num_next, seq_num_prev;
+       uint32_t i;
+       uint8_t flags = *p;
+       uint16_t begin_index, end_index, start_index;
+
+       // Perform length checking
+       if(l > MAXFRAGLEN)
+       {
+               LOG(2, s, t, "MPPP: discarding fragment larger than MAXFRAGLEN\n");
+               return;
+       }

 
 

-       if (!b)
+       if(!b)

        {
        {

-               LOG(3, s, t, "MPPP: Invalid bundle id: 0\n");
+               LOG(2, s, t, "MPPP: Invalid bundle id: 0\n");

                return;
        }
                return;
        }

-
-       begin_frame = (*p & 0x80);
-       end_frame = (*p & 0x40);
-       if (session[s].mssf)
+       // FIXME !! session[s].mssf means that the receiver wants to receive frames in mssf not means the receiver will send frames in mssf
+       /* if(session[s].mssf)

        {
                // Get 12 bit for seq number
        {
                // 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;
+               seq_num = ntohs((*(uint16_t *) p) & 0xFF0F);

                p += 2;
                l -= 2;
                p += 2;
                l -= 2;

-               seq_num = short_seq_num2;

                // After this point the pointer should be advanced 2 bytes
                // 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);
+               LOG(3, s, t, "MPPP: 12 bits, sequence number: %d\n",seq_num);

        }
        }

-       else
+       else */

        {
                // Get 24 bit for seq number
        {
                // Get 24 bit for seq number

-               p++;

                seq_num = ntohl((*(uint32_t *) p) & 0xFFFFFF00);
                seq_num = ntohl((*(uint32_t *) p) & 0xFFFFFF00);

-               seq_num = seq_num >> 8;
-               p += 3;
+               p += 4;

                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);
        }
 
                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)
+       max_seq = this_bundle->max_seq;
+       maskSeq = max_seq - 1;
+
+       /*
+        * Expand sequence number to 32 bits, making it as close
+        * as possible to this_fragmentation->M.
+        */
+       seq_num |= this_fragmentation->M & ~maskSeq;
+       if ((int)(this_fragmentation->M - seq_num) > (int)(maskSeq >> 1))
+       {
+               seq_num += maskSeq + 1;
+       }
+       else if ((int)(seq_num - this_fragmentation->M) > (int)(maskSeq >> 1))

        {
        {

-               bundle[b].offset = 0;
-               bundle[b].pending_frag = 0;
+               seq_num -= maskSeq + 1; /* should never happen */

        }
 
        }
 

-       offset = bundle[b].offset;
-       if (begin_frame)
+       // calculate this fragment's offset from the begin seq in the bundle
+       frag_offset = (int) (seq_num - this_fragmentation->start_seq);
+       start_index = this_fragmentation->start_index;
+       
+       sess_local[s].last_seq = seq_num;
+
+       uint32_t min;
+
+       if (seq_num < this_fragmentation->M)
+       {
+               min = seq_num;
+               this_fragmentation->M = seq_num;
+       }
+       else

        {
        {

-               // Check for previous non-assembled frames
-               int error = 0;
-               if (bundle[b].pending_frag)
+               min = sess_local[(this_bundle->members[0])].last_seq;
+               for (i = 1; i < this_bundle->num_of_links; i++)

                {
                {

-                       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;
-                       }
+                       uint32_t s_seq = sess_local[(this_bundle->members[i])].last_seq;
+                       if (s_seq < min)
+                               min = s_seq;
+               }
+               this_fragmentation->M = min;
+       }

 
 

-                       if (seq_num-offset < 0 || seq_num-offset > MAXFRAGNUM)
+       if (min >= (this_fragmentation->start_seq + this_bundle->num_of_links))
+       {
+               // Find the new start sequence, the previous frag are lost
+               // calculate M offset of the M seq in the bundle
+               int M_offset = (int) (min - this_fragmentation->start_seq);
+               begin_index = (M_offset + this_fragmentation->start_index) & MAXFRAGNUM_MASK;
+
+               if (M_offset >= MAXFRAGNUM)
+               {
+                       // There have a long break of the link !!!!!!!!
+                       // M_offset is bigger that the fragmentation buffer size
+                       LOG(3, s, t, "MPPP: M_offset out of range, min:%d, begin_seq:%d, size frag:%d\n", min, this_fragmentation->start_seq, l);
+
+                       // Set new Start sequence
+                       this_fragmentation->start_index = begin_index;
+                       this_fragmentation->start_seq = min;
+                       M_offset = 0;
+                       // recalculate the fragment offset from the new begin seq in the bundle
+                       frag_offset = (int) (seq_num - min);
+               }
+               else if (M_offset > 0)
+               {
+                       uint32_t b_seq = min;
+                       if ((min == seq_num) && begin_frame)

                        {
                        {

-                               LOG(2, s, t, "ERROR: Index out of range fn(last):%d, bundle:%d\n",fn,b);
-                               return;
+                               // Set new Start sequence
+                               this_fragmentation->start_index = begin_index;
+                               this_fragmentation->start_seq = min;
+                               frag_offset = 0;

                        }
                        }

-                       /////////////////////////////////////////////////////
-                       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++)
+                       else

                        {
                        {

-                               if (!frag[b].fragment[fn].length)
+                               if (min == seq_num)

                                {
                                {

-                                       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;
+                                       M_offset--;
+                                       begin_index = (begin_index ? (begin_index -1) : (MAXFRAGNUM -1));
+                                       b_seq--;

                                }
 
                                }
 

-                               if (cur_len + frag[b].fragment[fn].length > MAXETHER)
+                               // Find the Begin sequence
+                               while (this_fragmentation->fragment[begin_index].length)

                                {
                                {

-                                       LOG(2, s, t, "MPPP: ERROR: very long frame after assembling %d\n", frag[b].fragment[fn].length+cur_len);
-                                       error = 1;
-                                       break;
+                                       if (b_seq == this_fragmentation->fragment[begin_index].seq)
+                                       {
+                                               if (this_fragmentation->fragment[begin_index].flags & MP_BEGIN)
+                                                       break;
+                                       }
+                                       else
+                                       {
+                                               // This fragment is lost, it was never completed the packet.
+                                               LOG(3, this_fragmentation->fragment[begin_index].sid, this_fragmentation->fragment[begin_index].tid,
+                                                       "MPPP: (FIND) seq_num:%d frag_index:%d flags:%d is LOST\n",
+                                                       this_fragmentation->fragment[begin_index].seq, begin_index, this_fragmentation->fragment[begin_index].flags);
+                                               // this frag is lost
+                                               this_fragmentation->fragment[begin_index].length = 0;
+                                               this_fragmentation->fragment[begin_index].flags = 0;
+                                               break;
+                                       }
+                                       begin_index = (begin_index ? (begin_index -1) : (MAXFRAGNUM -1));
+                                       b_seq--;

                                }
 
                                }
 

-                               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));
+                               // begin sequence found ?
+                               if (this_fragmentation->fragment[begin_index].length)
+                               {
+                                       // Set new Start sequence
+                                       this_fragmentation->start_index = begin_index;
+                                       this_fragmentation->start_seq = b_seq;
+                                       // recalculate the fragment offset from the new begin seq in the bundle
+                                       frag_offset = (int) (seq_num - b_seq);
+                               }
+                       }
+               }
+       }
+       else if ((this_fragmentation->fragment[start_index].length) &&
+                        (!(this_fragmentation->fragment[start_index].flags & MP_BEGIN)))
+       {
+               uint32_t f_seq = this_fragmentation->start_seq;
+               end_index = start_index;
+               // Find the Begin sequence
+               while (this_fragmentation->fragment[end_index].length)
+               {
+                       if (f_seq == this_fragmentation->fragment[end_index].seq)
+                       {
+                               if (this_fragmentation->fragment[end_index].flags & MP_BEGIN)
+                                       break;
+                       }
+                       else
+                       {
+                               // This fragment is lost, it was never completed the packet.
+                               LOG(3, this_fragmentation->fragment[end_index].sid, this_fragmentation->fragment[end_index].tid,
+                                       "MPPP: (FIND2) seq_num:%d frag_index:%d flags:%d is LOST\n",
+                                       this_fragmentation->fragment[end_index].seq, end_index, this_fragmentation->fragment[end_index].flags);
+                               // this frag is lost
+                               this_fragmentation->fragment[end_index].length = 0;
+                               this_fragmentation->fragment[end_index].flags = 0;
+                               break;

                        }
                        }

+                       end_index = (end_index +1) & MAXFRAGNUM_MASK;
+                       f_seq++;
+               }
+
+               // Set new Start sequence
+               this_fragmentation->start_index = end_index;
+               this_fragmentation->start_seq = f_seq;
+               // recalculate the fragment offset from the new begin seq in the bundle
+               frag_offset = (int) (seq_num - f_seq);
+       }
+
+       // discard this fragment if the packet comes before the start sequence
+       if (frag_offset < 0)
+       {
+               // this packet comes before the next
+               LOG(3, s, t, "MPPP: packet comes before the next, seq:%d, begin_seq:%d, size frag:%d\n", seq_num, this_fragmentation->start_seq, l);
+               return;
+       }
+       
+       // discard if frag_offset is bigger that the fragmentation buffer size
+       if (frag_offset >= MAXFRAGNUM)
+       {
+               // frag_offset is bigger that the fragmentation buffer size
+               LOG(3, s, t, "MPPP: Index out of range, seq:%d, begin_seq:%d, size frag:%d\n", seq_num, this_fragmentation->start_seq, l);
+               return;
+       }
+
+       //caculate received fragment's index in the fragment array
+       frag_index = (frag_offset + this_fragmentation->start_index) & MAXFRAGNUM_MASK;
+
+       {
+               // insert the frame in it's place
+               fragmentt *this_frag = &this_fragmentation->fragment[frag_index];
+
+               if (this_frag->length > 0)
+                       // This fragment is lost, It was around the buffer and it was never completed the packet.
+                       LOG(3, this_frag->sid, this_frag->tid, "MPPP: (INSERT) seq_num:%d frag_index:%d flags:%d is LOST\n",
+                               this_frag->seq, frag_index, this_frag->flags);
+
+               this_frag->length = l;
+               this_frag->sid = s;
+               this_frag->flags = flags;
+               this_frag->seq = seq_num;
+               memcpy(this_frag->data, p, l);

 
 

-                       if (!error)
+               LOG(4, s, t, "MPPP: seq_num:%d frag_index:%d INSERTED flags: %02X\n",  seq_num, frag_index, flags);
+
+               //next frag index
+               frag_index_next = (frag_index + 1) & MAXFRAGNUM_MASK;
+               //previous frag index
+               frag_index_prev = (frag_index - 1) & MAXFRAGNUM_MASK;
+               // next seq
+               seq_num_next = seq_num + 1;
+               // previous seq
+               seq_num_prev = seq_num - 1;
+
+               if ((frag_index_next != this_fragmentation->start_index) && this_fragmentation->fragment[frag_index_next].length)
+               {
+                       // check if the next frag is a lost fragment
+                       if (this_fragmentation->fragment[frag_index_next].seq != seq_num_next)

                        {
                        {

-                               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));
+                               // This fragment is lost, It was around the buffer and it was never completed the packet.
+                               LOG(3, this_fragmentation->fragment[frag_index_next].sid, this_fragmentation->fragment[frag_index_next].tid,
+                                       "MPPP: (NEXT) seq_num:%d frag_index:%d flags:%d is LOST\n",
+                                       this_fragmentation->fragment[frag_index_next].seq, frag_index_next, this_fragmentation->fragment[frag_index_next].flags);
+                               // this frag is lost
+                               this_fragmentation->fragment[frag_index_next].length = 0;
+                               this_fragmentation->fragment[frag_index_next].flags = 0;
+
+                               if (begin_frame && (!end_frame)) return; // assembling frame failed

                        }
                }
                        }
                }

-               //////////////////////////////////////////
-               bundle[b].seq_num_m = seq_num;
-               if (end_frame)
+
+               if ((frag_index != this_fragmentation->start_index) && this_fragmentation->fragment[frag_index_prev].length)

                {
                {

-                       // 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)
+                       // check if the next frag is a lost fragment
+                       if (this_fragmentation->fragment[frag_index_prev].seq != seq_num_prev)

                        {
                        {

-                               bundle[b].offset = seq_num;
-                               LOG(4, s, t, "MPPP: Setting offset to: %d\n",bundle[b].offset);
+                               // This fragment is lost, It was around the buffer and it was never completed the packet.
+                               LOG(3, this_fragmentation->fragment[frag_index_prev].sid, this_fragmentation->fragment[frag_index_prev].tid,
+                                       "MPPP: (PREV) seq_num:%d frag_index:%d flags:%d is LOST\n",
+                                       this_fragmentation->fragment[frag_index_prev].seq, frag_index_prev, this_fragmentation->fragment[frag_index_prev].flags);
+
+                               this_fragmentation->fragment[frag_index_prev].length = 0;
+                               this_fragmentation->fragment[frag_index_prev].flags = 0;
+
+                               if (end_frame && (!begin_frame)) return; // assembling frame failed

                        }
                }
                        }
                }

+
+assembling_frame:
+               // try to assemble the frame that has the received fragment as a member         
+               // get the beginning of this frame
+               begin_index = end_index = this_fragmentation->start_index;
+               if (this_fragmentation->fragment[begin_index].length)
+               {
+                       if (!(this_fragmentation->fragment[begin_index].flags & MP_BEGIN))
+                               return; // assembling frame failed
+               }

                else
                else

+                       return; // assembling frame failed
+
+               // get the end of his frame
+               while (this_fragmentation->fragment[end_index].length)
+               {
+                       if (this_fragmentation->fragment[end_index].flags & MP_END)
+                               break;
+
+                       end_index = (end_index +1) & MAXFRAGNUM_MASK;
+
+                       if (end_index == this_fragmentation->start_index)
+                               return; // assembling frame failed
+               }
+
+               // return if a lost fragment is found
+               if (!(this_fragmentation->fragment[end_index].length))
+                       return; // assembling frame failed
+
+               // assemble the packet
+               //assemble frame, process it, reset fragmentation
+               uint16_t cur_len = 4;   // This is set to 4 to leave 4 bytes for function processipin
+
+               LOG(4, s, t, "MPPP: processing fragments from %d to %d\n", begin_index, end_index);
+               // Push to the receive buffer
+
+               for (i = begin_index;; i = (i + 1) & MAXFRAGNUM_MASK)

                {
                {

-                       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)
+                       this_frag = &this_fragmentation->fragment[i];
+                       if(cur_len + this_frag->length > MAXETHER)

                        {
                        {

-                               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;
+                               LOG(2, s, t, "MPPP: discarding reassembled frames larger than MAXETHER\n");
+                               break;

                        }
                        }

-                       // Perform length checking
-                       if (l > MAXFRAGLEN)
+
+                       memcpy(this_fragmentation->reassembled_frame+cur_len, this_frag->data, this_frag->length);
+                       LOG(5, s, t, "MPPP: processing frame at %d, with len %d\n", i, this_frag->length);
+
+                       cur_len += this_frag->length;
+                       if (i == end_index)

                        {
                        {

-                               LOG(2, s, t, "MPPP: ERROR: very long fragment length (1)\n");
-                               return;
+                               this_fragmentation->re_frame_len = cur_len;
+                               this_fragmentation->re_frame_begin_index = begin_index;
+                               this_fragmentation->re_frame_end_index = end_index;
+                               // Process the resassembled frame
+                               LOG(5, s, t, "MPPP: Process the reassembled frame, len=%d\n",cur_len);
+                               processmpframe(s, t, this_fragmentation->reassembled_frame, this_fragmentation->re_frame_len, 1);
+                               break;

                        }
                        }

-                       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)
+
+               // Set reassembled frame length to zero after processing it
+               this_fragmentation->re_frame_len = 0;
+               for (i = begin_index;; i = (i + 1) & MAXFRAGNUM_MASK)

                {
                {

-                       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;
+                       this_fragmentation->fragment[i].length = 0;      // Indicates that this fragment has been consumed
+                       this_fragmentation->fragment[i].flags = 0;
+                       if (i == end_index)
+                               break;

                }
                }

-               // Perform length checking
-               if (l > MAXFRAGLEN)
+
+               // Set the new start_index and start_seq
+               this_fragmentation->start_index = (end_index + 1) & MAXFRAGNUM_MASK;
+               this_fragmentation->start_seq = this_fragmentation->fragment[end_index].seq + 1;
+
+               LOG(4, s, t, "MPPP after assembling: start index is = %d, start seq=%d\n", this_fragmentation->start_index, this_fragmentation->start_seq);
+
+               begin_index = this_fragmentation->start_index;
+               if (this_fragmentation->fragment[begin_index].length)

                {
                {

-                       LOG(2, s, t, "MPPP: ERROR: very long fragment length (2).\n");
-                       return;
+                       if (this_fragmentation->fragment[begin_index].seq == this_fragmentation->start_seq)
+                       {
+                               if (this_fragmentation->fragment[begin_index].flags & MP_BEGIN)
+                                       goto assembling_frame;
+                       }
+                       else
+                       {
+                               LOG(3, this_fragmentation->fragment[begin_index].sid, this_fragmentation->fragment[begin_index].tid,
+                                       "MPPP: START seq_num:%d frag_index:%d flags:%d is LOST\n",
+                                       this_fragmentation->fragment[begin_index].seq, begin_index, this_fragmentation->fragment[begin_index].flags);
+                               this_fragmentation->fragment[begin_index].length = 0;
+                               this_fragmentation->fragment[begin_index].flags = 0;
+                       }

                }
                }

-               frag[b].fragment[seq_num - offset].length = l;
-               memcpy(frag[b].fragment[seq_num - offset].data, p, l);

        }
        }

+
+       return;

 }
 
 // process IPv6 packet received
 }
 
 // process IPv6 packet received


@@ -1993,12 +2265,7 @@ void processipv6in(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
                snoop_send_packet(p, l, session[s].snoop_ip, session[s].snoop_port);
        }
 
                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++;
+       update_sessions_in_stat(s, l);

 
        eth_tx += l;
 
 
        eth_tx += l;
 


@@ -2269,7 +2536,7 @@ uint8_t *makeppp(uint8_t *b, int size, uint8_t *p, int l, sessionidt s, tunnelid
                {
                        // Set the multilink bits
                        uint16_t bits_send = mp_bits;
                {
                        // Set the multilink bits
                        uint16_t bits_send = mp_bits;

-                       *(uint16_t *) b = htons((bundle[bid].seq_num_t & 0xFF0F)|bits_send);
+                       *(uint16_t *) b = htons((bundle[bid].seq_num_t & 0x0FFF)|bits_send);

                        b += 2;
                }
                else
                        b += 2;
                }
                else


@@ -2293,7 +2560,7 @@ uint8_t *makeppp(uint8_t *b, int size, uint8_t *p, int l, sessionidt s, tunnelid
 
        if ((b - start) + l > size)
        {
 
        if ((b - start) + l > size)
        {

-               LOG(2, s, t, "makeppp would overflow buffer (size=%d, header+payload=%d)\n", size, (b - start) + l);
+               LOG(2, s, t, "makeppp would overflow buffer (size=%d, header+payload=%td)\n", size, (b - start) + l);

                return NULL;
        }
 
                return NULL;
        }