Implement Reset{Req,Ack} properly, as per rfc 1962.

(I completely mis-read the rfc last time 'round!)

This means:
  o Better CCP/WARN Reset diagnostics.
  o After we've sent a REQ and before we've received an ACK, we drop
    incoming compressed data and send another REQ.
  o Before sending an ACK, re-sequence all pending PRI_NORMAL data in
    the modem queue so that pending packets won't get to the peer
    *after* the ResetAck.
  o Send ACKs with the `identifier' from the REQ frame.
  o After we've received a correct ACK, duplicate ACKs are ok (and will
    reset our history).
  o Incorrect ACKs (not matching the last REQ) are moaned about and dropped.

Also,

  o Calculate the correct FCS after compressing a packet.  DEFLATE
    *may* produce an mbuf with more than a single link in the chain,
    but HdlcOutput didn't know how to calculate the FCS :-(
  o Make `struct fsm'::reqid a u_char, not an int.
    This fix will prevent us from sending id `255' 2,000,000,000 times
    before wrapping to `0' for another 2,000,000,000 sends :-/
  o Bump the version number a little.

The end result:  DEFLATE now works over an unreliable link layer.
                 I can txfr a 1.5Mb kernel over a (rather bad) null-modem
                 cable at an average of 21679 bytes per second using rcp.
Repeat after me: Don't test compression using a loopback ppp/tcp setup as
                 we never lose packets and therefore never have to reset!

1 files changed, 2 insertions, 2 deletions

diff --git a/usr.sbin/ppp/fsm.h b/usr.sbin/ppp/fsm.h
index d3527afae560..07ddb3bb540c 100644
--- a/usr.sbin/ppp/fsm.h
+++ b/usr.sbin/ppp/fsm.h
@@ -15,7 +15,7 @@
  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  *
- * $Id: fsm.h,v 1.12 1997/11/22 03:37:32 brian Exp $
+ * $Id: fsm.h,v 1.13 1997/12/03 10:23:47 brian Exp $
  *
  *	TODO:
  */
@@ -52,7 +52,7 @@ struct fsm {
   u_short max_code;
   int open_mode;
   int state;			/* State of the machine */
-  int reqid;			/* Next request id */
+  u_char reqid;			/* Next request id */
   int restart;			/* Restart counter value */
   int maxconfig;