From a43e859d63045b899215c742e3a6538c521d0f11 Mon Sep 17 00:00:00 2001
From: Brian Somers <brian@FreeBSD.org>
Date: Tue, 14 May 2002 00:59:28 +0000
Subject: [PATCH] Calculate the number of open links properly when deciding on
 whether to just send PROTO_IP packets when we've got only one link up in
 multi-link mode.

Problem noted by:	Adrian Close <adrian@fernhilltec.com.au>
MFC after:		1 week
---
 usr.sbin/ppp/mp.c | 21 ++++++++++-----------
 1 file changed, 10 insertions(+), 11 deletions(-)

diff --git a/usr.sbin/ppp/mp.c b/usr.sbin/ppp/mp.c
index bb26877029a..3e2ca1b5d53 100644
--- a/usr.sbin/ppp/mp.c
+++ b/usr.sbin/ppp/mp.c
@@ -668,12 +668,12 @@ mp_FillPhysicalQueues(struct bundle *bundle)
   struct mp *mp = &bundle->ncp.mp;
   struct datalink *dl, *fdl;
   size_t total, add, len;
-  int thislink, nlinks;
+  int thislink, nlinks, nopenlinks, sendasip;
   u_int32_t begin, end;
   struct mbuf *m, *mo;
   struct link *bestlink;
 
-  thislink = nlinks = 0;
+  thislink = nlinks = nopenlinks = 0;
   for (fdl = NULL, dl = bundle->links; dl; dl = dl->next) {
     /* Include non-open links here as mp->out.link will stay more correct */
     if (!fdl) {
@@ -683,6 +683,8 @@ mp_FillPhysicalQueues(struct bundle *bundle)
         thislink++;
     }
     nlinks++;
+    if (dl->state == DATALINK_OPEN)
+      nopenlinks++;
   }
 
   if (!fdl) {
@@ -714,7 +716,6 @@ mp_FillPhysicalQueues(struct bundle *bundle)
     }
 
     if (!mp_QueueLen(mp)) {
-      struct datalink *other;
       int mrutoosmall;
 
       /*
@@ -724,12 +725,10 @@ mp_FillPhysicalQueues(struct bundle *bundle)
        * in the outbound traffic going out as PROTO_IP or PROTO_IPV6 rather
        * than PROTO_MP.
        */
-      for (other = dl->next; other; other = other->next)
-        if (other->state == DATALINK_OPEN)
-          break;
 
       mrutoosmall = 0;
-      if (!other) {
+      sendasip = nopenlinks < 2;
+      if (sendasip) {
         if (dl->physical->link.lcp.his_mru < mp->peer_mrru) {
           /*
            * Actually, forget it.  This test is done against the MRRU rather
@@ -738,20 +737,20 @@ mp_FillPhysicalQueues(struct bundle *bundle)
            * too likely to upset some ppp implementations.
            */
           mrutoosmall = 1;
-          other = dl;
+          sendasip = 0;
         }
       }
 
-      bestlink = other ? &mp->link : &dl->physical->link;
+      bestlink = sendasip ? &dl->physical->link : &mp->link;
       if (!ncp_PushPacket(&bundle->ncp, &mp->out.af, bestlink))
         break;	/* Nothing else to send */
 
       if (mrutoosmall)
         log_Printf(LogDEBUG, "Don't send data as PROTO_IP, MRU < MRRU\n");
-      else if (!other)
+      else if (sendasip)
         log_Printf(LogDEBUG, "Sending data as PROTO_IP, not PROTO_MP\n");
 
-      if (!other) {
+      if (sendasip) {
         add = link_QueueLen(&dl->physical->link);
         if (add) {
           /* this link has got stuff already queued.  Let it continue */