[src/netbsd-1-4]: src/sys/netinet Pull up revision 1.23 (via patch, requested...

[he <he%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/50d6cb1003ed
branches:  netbsd-1-4
changeset: 471286:50d6cb1003ed
user:      he <he%NetBSD.org@localhost>
date:      Sat Apr 14 21:14:26 2001 +0000

description:
Pull up revision 1.23 (via patch, requested by darrenr):
  Fix bug related to fragment cache handling.

diffstat:

 sys/netinet/ip_frag.c |  33 +++++++++++++++++++++++++++------
 1 files changed, 27 insertions(+), 6 deletions(-)

diffs (82 lines):

diff -r 0ee1f85ab9d7 -r 50d6cb1003ed sys/netinet/ip_frag.c
--- a/sys/netinet/ip_frag.c     Thu Apr 05 12:18:09 2001 +0000
+++ b/sys/netinet/ip_frag.c     Sat Apr 14 21:14:26 2001 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: ip_frag.c,v 1.14.2.1 1999/12/20 21:07:13 he Exp $      */
+/*     $NetBSD: ip_frag.c,v 1.14.2.2 2001/04/14 21:14:26 he Exp $      */
 
 /*
  * Copyright (C) 1993-1998 by Darren Reed.
@@ -9,7 +9,7 @@
  */
 #if !defined(lint)
 #if defined(__NetBSD__)
-static const char rcsid[] = "$NetBSD: ip_frag.c,v 1.14.2.1 1999/12/20 21:07:13 he Exp $";
+static const char rcsid[] = "$NetBSD: ip_frag.c,v 1.14.2.2 2001/04/14 21:14:26 he Exp $";
 #else
 static const char sccsid[] = "@(#)ip_frag.c    1.11 3/24/96 (C) 1993-1995 Darren Reed";
 static const char rcsid[] = "@(#)Id: ip_frag.c,v 2.4.2.3 1999/09/18 15:03:54 darrenr Exp ";
@@ -141,8 +141,11 @@
 u_int pass;
 ipfr_t *table[];
 {
-       ipfr_t  **fp, *fra, frag;
-       u_int   idx;
+       ipfr_t **fp, *fra, frag;
+       u_int idx, off;
+
+       if (!(fin->fin_fi.fi_fl & FI_FRAG))
+               return NULL;
 
        frag.ipfr_p = ip->ip_p;
        idx = ip->ip_p;
@@ -196,7 +199,10 @@
        /*
         * Compute the offset of the expected start of the next packet.
         */
-       fra->ipfr_off = (ip->ip_off & IP_OFFMASK) + (fin->fin_dlen >> 3);
+       off = ip->ip_off & IP_OFFMASK;
+       if (!off)
+               fra->ipfr_seen0 = 1;
+       fra->ipfr_off = off + (fin->fin_dlen >> 3);
        ATOMIC_INC(ipfr_stats.ifs_new);
        ATOMIC_INC(ipfr_inuse);
        return fra;
@@ -248,6 +254,9 @@
        ipfr_t  *f, frag;
        u_int   idx;
 
+       if (!(fin->fin_fi.fi_fl & FI_FRAG))
+               return NULL;
+
        /*
         * For fragments, we record protocol, packet id, TOS and both IP#'s
         * (these should all be the same for all fragments of a packet).
@@ -274,6 +283,19 @@
                          IPFR_CMPSZ)) {
                        u_short atoff, off;
 
+                       /*
+                        * XXX - We really need to be guarding against the
+                        * retransmission of (src,dst,id,offset-range) here
+                        * because a fragmented packet is never resent with
+                        * the same IP ID#.
+                        */
+                       off = ip->ip_off & IP_OFFMASK;
+                       if (f->ipfr_seen0) {
+                               if (!off || (fin->fin_fi.fi_fl & FI_SHORT))
+                                       continue;
+                       } else if (!off)
+                               f->ipfr_seen0 = 1;
+
                        if (f != table[idx]) {
                                /*
                                 * move fragment info. to the top of the list
@@ -286,7 +308,6 @@
                                f->ipfr_prev = NULL;
                                table[idx] = f;
                        }
-                       off = ip->ip_off & IP_OFFMASK;
                        atoff = off + (fin->fin_dlen >> 3);
                        /*
                         * If we've follwed the fragments, and this is the