From 82248353c8fd7322e39e475f73d18db2536a71fe Mon Sep 17 00:00:00 2001
From: Brendan O'Dea <bod@optus.net>
Date: Thu, 25 Nov 2004 12:41:35 +0000
Subject: [PATCH] reinstate sendccp as initccp; send only once

---
 Changes  |  2 +-
 l2tpns.h |  3 ++-
 ppp.c    | 53 +++++++++++++++++++++++++++++++++++++++++++----------
 3 files changed, 46 insertions(+), 12 deletions(-)

diff --git a/Changes b/Changes
index 793b695..59dde80 100644
--- a/Changes
+++ b/Changes
@@ -1,5 +1,5 @@
 * Thu Nov 25 2004 Brendan O'Dea <bod@optusnet.com.au> 2.0.9
-- Drop sendccp.  If client sends a CCP request for compression just NAK it.
+- Revise CCP, send ConfigReq once only.
 - Don't copy the old buffer into Config{Nak,Rej} LCP responses (oops);
   add length checks when appending.
 - Have makeppp print a backtrace on overflow.
diff --git a/l2tpns.h b/l2tpns.h
index 6859236..c73727b 100644
--- a/l2tpns.h
+++ b/l2tpns.h
@@ -1,5 +1,5 @@
 // L2TPNS Global Stuff
-// $Id: l2tpns.h,v 1.36 2004-11-25 02:45:27 bodea Exp $
+// $Id: l2tpns.h,v 1.37 2004-11-25 12:41:35 bodea Exp $
 
 #ifndef __L2TPNS_H__
 #define __L2TPNS_H__
@@ -205,6 +205,7 @@ sessiont;
 
 #define SF_IPCP_ACKED	1	// Has this session seen an IPCP Ack?
 #define SF_LCP_ACKED	2	// LCP negotiated
+#define SF_CCP_ACKED	4	// CCP negotiated
 
 typedef struct {
 	u32	cin;
diff --git a/ppp.c b/ppp.c
index 9467ef1..1207b3c 100644
--- a/ppp.c
+++ b/ppp.c
@@ -1,6 +1,6 @@
 // L2TPNS PPP Stuff
 
-char const *cvs_id_ppp = "$Id: ppp.c,v 1.28 2004-11-25 02:45:27 bodea Exp $";
+char const *cvs_id_ppp = "$Id: ppp.c,v 1.29 2004-11-25 12:41:35 bodea Exp $";
 
 #include <stdio.h>
 #include <string.h>
@@ -23,6 +23,8 @@ extern u32 eth_tx;
 extern time_t time_now;
 extern struct configt *config;
 
+static void initccp(tunnelidt t, sessionidt s);
+
 // Process PAP messages
 void processpap(tunnelidt t, sessionidt s, u8 *p, u16 l)
 {
@@ -589,8 +591,8 @@ void processipcp(tunnelidt t, sessionidt s, u8 *p, u16 l)
 
 		LOG(3, session[s].ip, s, t, "IPCP Acked, session is now active\n");
 
-		// clear  LCP_ACKED flag  for possible fast renegotiaion for routers
-		session[s].flags &= ~SF_LCP_ACKED;
+		// clear LCP_ACKED/CCP_ACKED flag for possible fast renegotiaion for routers
+		session[s].flags &= ~(SF_LCP_ACKED|SF_CCP_ACKED);
 
 		return;
 	}
@@ -806,11 +808,23 @@ void processccp(tunnelidt t, sessionidt s, u8 *p, u16 l)
 	LOG_HEX(5, "CCP", p, l);
 	switch (l > 1 ? *p : 0)
 	{
+	case ConfigAck:
+		session[s].flags |= SF_CCP_ACKED;
+		return;
+
 	case ConfigReq:
-		if (l < 6)
-			*p = ConfigAck;		// accept no compression
-		else
-			*p = ConfigRej;		// reject
+		if (l < 6) // accept no compression
+		{
+			*p = ConfigAck;
+			break;
+		}
+
+		// compression requested--reject
+		*p = ConfigRej;
+
+		// send CCP request for no compression for our end if not negotiated
+		if (!(session[s].flags & SF_CCP_ACKED))
+			initccp();
 
 		break;
 
@@ -924,10 +938,10 @@ u8 *makeppp(u8 *b, int size, u8 *p, int l, tunnelidt t, sessionidt s, u16 mtype)
 	return b;
 }
 
-// Send initial LCP ConfigReq
+// Send initial LCP ConfigReq for PAP, set magic no.
 void initlcp(tunnelidt t, sessionidt s)
 {
-	char b[500] = {0}, *q;
+	char b[500], *q;
 
 	if (!(q = makeppp(b, sizeof(b), NULL, 0, t, s, PPPLCP)))
 		return;
@@ -942,5 +956,24 @@ void initlcp(tunnelidt t, sessionidt s)
 	*(u8 *)(q + 10) = 3;
 	*(u8 *)(q + 11) = 4;
 	*(u16 *)(q + 12) = htons(PPPPAP); // PAP
-	tunnelsend(b, 12 + 14, t);
+
+	LOG_HEX(5, "PPPLCP", q, 14);
+	tunnelsend(b, (q - b) + 14, t);
+}
+
+// Send CCP request for no compression
+static void sendccp(tunnelidt t, sessionidt s)
+{
+	char b[500], *q;
+
+	if (!(q = makeppp(b, sizeof(b), NULL, 0, t, s, PPPCCP)))
+		return;
+
+	LOG(4, 0, s, t, "Sending CCP ConfigReq for no compression\n");
+	*q = ConfigReq;
+	*(u8 *)(q + 1) = (time_now % 255) + 1; // ID
+	*(u16 *)(q + 2) = htons(4); // Length
+
+	LOG_HEX(5, "PPPCCP", q, 4);
+	tunnelsend(b, (q - b) + 4 , t);
 }
-- 
2.20.1