X-Git-Url: http://git.sameswireless.fr/l2tpns.git/blobdiff_plain/43d9ea52f9d9d7f993c02e29742f084c4f2776eb..f5354e17542c0c11b00e2c8fb48a989ba5e47bcf:/ppp.c

diff --git a/ppp.c b/ppp.c
index e805e22..a8a355d 100644
--- a/ppp.c
+++ b/ppp.c
@@ -12,6 +12,11 @@
 #include "tbf.h"
 #include "cluster.h"
 
+#ifdef LAC
+#include "l2tplac.h"
+#endif
+#include "pppoe.h"
+
 extern tunnelt *tunnel;
 extern bundlet *bundle;
 extern fragmentationt *frag;
@@ -21,6 +26,7 @@ extern int tunfd;
 extern char hostname[];
 extern uint32_t eth_tx;
 extern time_t time_now;
+extern uint64_t time_now_ms;
 extern configt *config;
 
 static int add_lcp_auth(uint8_t *b, int size, int authtype);
@@ -99,6 +105,14 @@ void processpap(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
 		LOG(3, s, t, "PAP login %s/%s\n", user, pass);
 	}
 
+#ifdef LAC
+	if ((!config->disable_lac_func) && lac_conf_forwardtoremotelns(s, user))
+	{
+		// Creating a tunnel/session has been started
+		return;
+	}
+#endif
+
 	if (session[s].ip || !(r = radiusnew(s)))
 	{
 		// respond now, either no RADIUS available or already authenticated
@@ -250,6 +264,16 @@ void processchap(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
 		packet.username = calloc(l + 1, 1);
 		memcpy(packet.username, p, l);
 
+#ifdef LAC
+		if ((!config->disable_lac_func) && lac_conf_forwardtoremotelns(s, packet.username))
+		{
+			free(packet.username);
+			free(packet.password);
+			// Creating a tunnel/session has been started
+			return;
+		}
+#endif
+
 		run_plugins(PLUGIN_PRE_AUTH, &packet);
 		if (!packet.continue_auth)
 		{
@@ -402,7 +426,7 @@ void lcp_open(sessionidt s, tunnelidt t)
 	}
 }
 
-static void lcp_restart(sessionidt s)
+void lcp_restart(sessionidt s)
 {
 	session[s].ppp.phase = Establish;
 	// This-Layer-Down
@@ -535,7 +559,7 @@ void processlcp(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
 	if (session[s].die) // going down...
 		return;
 
-	LOG((*p == EchoReq || *p == EchoReply) ? 4 : 3, s, t,
+	LOG(((*p == EchoReq || *p == EchoReply) ? 4 : 3), s, t,
 		"LCP: recv %s\n", ppp_code(*p));
 
 	if (config->debug > 3) dumplcp(p, l);
@@ -1180,24 +1204,24 @@ static void setepdis(epdist *ep1, epdist ep2)
 
 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
+	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;
+			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)
@@ -1820,7 +1844,7 @@ void processmpin(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
 	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;
+	uint16_t begin_index, end_index;
 
 	// Perform length checking
 	if(l > MAXFRAGLEN)
@@ -1873,312 +1897,323 @@ void processmpin(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
 
 	// 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;
+	// calculate the jitter average
+	uint32_t ljitter = time_now_ms - sess_local[s].prev_time;
+	if (ljitter > 0)
+	{
+		sess_local[s].jitteravg = (sess_local[s].jitteravg + ljitter)>>1;
+		sess_local[s].prev_time = time_now_ms;
+	}
+
+	uint32_t Mmin;
 
 	if (seq_num < this_fragmentation->M)
 	{
-		min = seq_num;
+		Mmin = seq_num;
 		this_fragmentation->M = seq_num;
 	}
 	else
 	{
-		min = sess_local[(this_bundle->members[0])].last_seq;
+		Mmin = sess_local[(this_bundle->members[0])].last_seq;
 		for (i = 1; i < this_bundle->num_of_links; i++)
 		{
 			uint32_t s_seq = sess_local[(this_bundle->members[i])].last_seq;
-			if (s_seq < min)
-				min = s_seq;
+			if (s_seq < Mmin)
+				Mmin = s_seq;
 		}
-		this_fragmentation->M = min;
+		this_fragmentation->M = Mmin;
 	}
 
-	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;
+	// calculate M offset of the M seq in the bundle
+	int M_offset = (int) (Mmin - this_fragmentation->start_seq);
 
-		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)
-			{
-				// Set new Start sequence
-				this_fragmentation->start_index = begin_index;
-				this_fragmentation->start_seq = min;
-				frag_offset = 0;
-			}
-			else
-			{
-				if (min == seq_num)
-				{
-					M_offset--;
-					begin_index = (begin_index ? (begin_index -1) : (MAXFRAGNUM -1));
-					b_seq--;
-				}
-
-				// Find the Begin sequence
-				while (this_fragmentation->fragment[begin_index].length)
-				{
-					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--;
-				}
-
-				// 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)))
+	if (M_offset >= MAXFRAGNUM)
 	{
-		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++;
-		}
+		// 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\n", Mmin, this_fragmentation->start_seq);
+
+		// Calculate the new start index, the previous frag are lost
+		begin_index = (M_offset + this_fragmentation->start_index) & MAXFRAGNUM_MASK;
 
 		// Set new Start sequence
-		this_fragmentation->start_index = end_index;
-		this_fragmentation->start_seq = f_seq;
+		this_fragmentation->start_index = begin_index;
+		this_fragmentation->start_seq = Mmin;
+		M_offset = 0;
 		// recalculate the fragment offset from the new begin seq in the bundle
-		frag_offset = (int) (seq_num - f_seq);
+		frag_offset = (int) (seq_num - Mmin);
 	}
 
 	// 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);
+		LOG(3, s, t, "MPPP: (COMES BEFORE) the next, seq:%d, begin_seq:%d, size_frag:%d, flags:%02X is LOST\n", seq_num, this_fragmentation->start_seq, l, flags);
 		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);
+		LOG(3, s, t, "MPPP: Index out of range, seq:%d, begin_seq:%d\n", seq_num, this_fragmentation->start_seq);
 		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)
+	// 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:%02X is LOST\n",
+			this_frag->seq, frag_index, this_frag->flags);
+
+	this_frag->length = l;
+	this_frag->sid = s;
+	this_frag->tid = t;
+	this_frag->flags = flags;
+	this_frag->seq = seq_num;
+	this_frag->jitteravg = sess_local[s].jitteravg;
+	memcpy(this_frag->data, p, l);
+
+	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;
+
+	// Clean the buffer and log the lost fragments
+	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)
+		{
 			// 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);
-
-		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)
+			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:%02X 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
+		}
+	}
+
+	// Clean the buffer and log the lost fragments
+	if ((frag_index != this_fragmentation->start_index) && this_fragmentation->fragment[frag_index_prev].length)
+	{
+		// check if the next frag is a lost fragment
+		if (this_fragmentation->fragment[frag_index_prev].seq != seq_num_prev)
 		{
-			// check if the next frag is a lost fragment
-			if (this_fragmentation->fragment[frag_index_next].seq != seq_num_next)
-			{
-				// 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;
+			// 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:%02X is LOST\n",
+				this_fragmentation->fragment[frag_index_prev].seq, frag_index_prev,
+				this_fragmentation->fragment[frag_index_prev].flags);
 
-				if (begin_frame && (!end_frame)) return; // assembling frame failed
-			}
+			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
 		}
+	}
 
-		if ((frag_index != this_fragmentation->start_index) && this_fragmentation->fragment[frag_index_prev].length)
+find_frame:
+	begin_index = this_fragmentation->start_index;
+	uint32_t b_seq = this_fragmentation->start_seq;
+	// Try to find a Begin sequence from the start_seq sequence to M sequence
+	while (b_seq < Mmin)
+	{
+		if (this_fragmentation->fragment[begin_index].length)
 		{
-			// check if the next frag is a lost fragment
-			if (this_fragmentation->fragment[frag_index_prev].seq != seq_num_prev)
+			if (b_seq == this_fragmentation->fragment[begin_index].seq)
 			{
-				// 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 (this_fragmentation->fragment[begin_index].flags & MP_BEGIN)
+				{
+					int isfoundE = 0;
+					// Adjust the new start sequence and start index
+					this_fragmentation->start_index = begin_index;
+					this_fragmentation->start_seq = b_seq;
+					// Begin Sequence found, now try to found the End Sequence to complete the frame
+					end_index = begin_index;
+					while (b_seq < Mmin)
+					{
+						if (this_fragmentation->fragment[end_index].length)
+						{
+							if (b_seq == this_fragmentation->fragment[end_index].seq)
+							{
+								if (this_fragmentation->fragment[end_index].flags & MP_END)
+								{
+									// The End sequence was found and the frame is complete
+									isfoundE = 1;
+									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: (FIND END) seq_num:%d frag_index:%d flags:%02X is LOST\n",
+									this_fragmentation->fragment[end_index].seq, begin_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;
+								// This frame is not complete find the next Begin
+								break;
+							}
+						}
+						else
+						{
+							// This frame is not complete find the next Begin if exist
+							break;
+						}
+						end_index = (end_index +1) & MAXFRAGNUM_MASK;
+						b_seq++;
+					}
 
-				if (end_frame && (!begin_frame)) return; // assembling frame failed
+					if (isfoundE)
+						// The End sequence was found and the frame is complete
+						break;
+					else
+						// find the next Begin
+						begin_index = end_index;
+				}
+			}
+			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 BEGIN) seq_num:%d frag_index:%d flags:%02X 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;
 			}
 		}
+		begin_index = (begin_index +1) & MAXFRAGNUM_MASK;
+		b_seq++;
+	}
 
 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)
+	// 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))
 		{
-			if (!(this_fragmentation->fragment[begin_index].flags & MP_BEGIN))
-				return; // assembling frame failed
-		}
-		else
+			LOG(3, this_fragmentation->fragment[begin_index].sid, this_fragmentation->fragment[begin_index].tid,
+				"MPPP: (NOT BEGIN) seq_num:%d frag_index:%d flags:%02X\n",
+				this_fragmentation->fragment[begin_index].seq, begin_index,
+				this_fragmentation->fragment[begin_index].flags);
+			// should occur only after an "M_Offset out of range"
+			// The start sequence must be a begin sequence
+			this_fragmentation->start_index = (begin_index +1) & MAXFRAGNUM_MASK;
+			this_fragmentation->start_seq++;
 			return; // assembling frame failed
+		}
+	}
+	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;
+	// get the end of his frame
+	while (this_fragmentation->fragment[end_index].length)
+	{
+		if (this_fragmentation->fragment[end_index].flags & MP_END)
+			break;
 
-			if (end_index == this_fragmentation->start_index)
-				return; // assembling frame failed
-		}
+		end_index = (end_index +1) & MAXFRAGNUM_MASK;
 
-		// return if a lost fragment is found
-		if (!(this_fragmentation->fragment[end_index].length))
+		if (end_index == this_fragmentation->start_index)
 			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
+	// return if a lost fragment is found
+	if (!(this_fragmentation->fragment[end_index].length))
+		return; // assembling frame failed
 
-		for (i = begin_index;; i = (i + 1) & MAXFRAGNUM_MASK)
-		{
-			this_frag = &this_fragmentation->fragment[i];
-			if(cur_len + this_frag->length > MAXETHER)
-			{
-				LOG(2, s, t, "MPPP: discarding reassembled frames larger than MAXETHER\n");
-				break;
-			}
+	// 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
 
-			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);
+	LOG(4, s, t, "MPPP: processing fragments from %d to %d\n", begin_index, end_index);
+	// Push to the receive buffer
 
-			cur_len += this_frag->length;
-			if (i == end_index)
-			{
-				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;
-			}
+	for (i = begin_index;; i = (i + 1) & MAXFRAGNUM_MASK)
+	{
+		this_frag = &this_fragmentation->fragment[i];
+		if(cur_len + this_frag->length > MAXETHER)
+		{
+			LOG(2, s, t, "MPPP: discarding reassembled frames larger than MAXETHER\n");
+			break;
 		}
 
-		// Set reassembled frame length to zero after processing it
-		this_fragmentation->re_frame_len = 0;
-		for (i = begin_index;; i = (i + 1) & MAXFRAGNUM_MASK)
+		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)
 		{
-			this_fragmentation->fragment[i].length = 0;      // Indicates that this fragment has been consumed
-			this_fragmentation->fragment[i].flags = 0;
-			if (i == end_index)
-				break;
+			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;
 		}
+	}
 
-		// 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;
+	// Set reassembled frame length to zero after processing it
+	this_fragmentation->re_frame_len = 0;
+	for (i = begin_index;; i = (i + 1) & MAXFRAGNUM_MASK)
+	{
+		this_fragmentation->fragment[i].length = 0;      // Indicates that this fragment has been consumed
+		this_fragmentation->fragment[i].flags = 0;
+		if (i == end_index)
+			break;
+	}
 
-		LOG(4, s, t, "MPPP after assembling: start index is = %d, start seq=%d\n", this_fragmentation->start_index, this_fragmentation->start_seq);
+	// 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)
-		{
-			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;
-			}
-		}
+	begin_index = this_fragmentation->start_index;
+	if ((this_fragmentation->fragment[begin_index].length) &&
+		(this_fragmentation->fragment[begin_index].seq != this_fragmentation->start_seq))
+	{
+		LOG(3, this_fragmentation->fragment[begin_index].sid, this_fragmentation->fragment[begin_index].tid,
+				"MPPP: (START) seq_num:%d frag_index:%d flags:%02X 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;
 	}
 
+	if (this_fragmentation->start_seq <= Mmin)
+		// It's possible to find other complete frame or lost frame.
+		goto find_frame;
+	else if ((this_fragmentation->fragment[begin_index].length) &&
+			  (this_fragmentation->fragment[begin_index].flags & MP_BEGIN))
+		// may be that the next frame is completed
+		goto assembling_frame;
+
 	return;
 }
 
@@ -2491,6 +2526,11 @@ uint8_t *makeppp(uint8_t *b, int size, uint8_t *p, int l, sessionidt s, tunnelid
 	uint16_t type = mtype;
 	uint8_t *start = b;
 
+	if (t == TUNNEL_ID_PPPOE)
+	{
+		return pppoe_makeppp(b, size, p, l, s, t, mtype, prio, bid, mp_bits);
+	}
+
 	if (size < 16) // Need more space than this!!
 	{
 		LOG(0, s, t, "makeppp buffer too small for L2TP header (size=%d)\n", size);
@@ -2571,6 +2611,85 @@ uint8_t *makeppp(uint8_t *b, int size, uint8_t *p, int l, sessionidt s, tunnelid
 	return b;
 }
 
+// fill in a L2TP message with a PPP frame,
+// returns start of PPP frame
+//(note: THIS ROUTINE CAN WRITES TO p[-28]).
+uint8_t *opt_makeppp(uint8_t *p, int l, sessionidt s, tunnelidt t, uint16_t mtype, uint8_t prio, bundleidt bid, uint8_t mp_bits)
+{
+	uint16_t hdr = 0x0002; // L2TP with no options
+	uint16_t type = mtype;
+	uint8_t *b = p;
+
+	if (t == TUNNEL_ID_PPPOE)
+	{
+		return opt_pppoe_makeppp(p, l, s, t, mtype, prio, bid, mp_bits);
+	}
+
+	// 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 (bid)
+	{
+		// Add the message type if this fragment has the begin bit set
+		if (mp_bits & MP_BEGIN)
+		{
+			b -= 2;
+			*(uint16_t *) b = htons(mtype); // Message type
+		}
+
+		// Set the sequence number and (B)egin (E)nd flags
+		if (session[s].mssf)
+		{
+			// Set the multilink bits
+			uint16_t bits_send = mp_bits;
+			b -= 2;
+			*(uint16_t *) b = htons((bundle[bid].seq_num_t & 0x0FFF)|bits_send);
+		}
+		else
+		{
+			b -= 4;
+			*(uint32_t *) b = htonl(bundle[bid].seq_num_t);
+			// Set the multilink bits
+			*b = mp_bits;
+		}
+
+		bundle[bid].seq_num_t++;
+	}
+
+	if (type < 0x100 && session[s].flags & SESSION_PFC)
+	{
+		b--;
+		*b = type;
+	}
+	else
+	{
+		b -= 2;
+		*(uint16_t *) b = htons(type);
+	}
+
+	if (type == PPPLCP || !(session[s].flags & SESSION_ACFC))
+	{
+		b -= 2;
+		*(uint16_t *) b = htons(0xFF03); // HDLC header
+	}
+
+	if (prio) hdr |= 0x0100; // set priority bit
+	b -= 2;
+	*(uint16_t *) b = htons(session[s].far); // session
+	b -= 2;
+	*(uint16_t *) b = htons(tunnel[t].far); // tunnel
+	b -= 2;
+	*(uint16_t *) b = htons(hdr);
+
+	return b;
+}
+
 static int add_lcp_auth(uint8_t *b, int size, int authtype)
 {
 	int len = 0;