svn commit: r200141 - stable/8/sys/netipsec

[Bjoern A. Zeeb]

Author: bz
Date: Sat Dec  5 19:03:20 2009
New Revision: 200141
URL: http://svn.freebsd.org/changeset/base/200141

Log:
  MFC r199896:
    Directly send data uncompressed if the packet payload size is lower than
    the compression algorithm threshold.

Modified:
  stable/8/sys/netipsec/xform_ipcomp.c
Directory Properties:
  stable/8/sys/   (props changed)
  stable/8/sys/amd64/include/xen/   (props changed)
  stable/8/sys/cddl/contrib/opensolaris/   (props changed)
  stable/8/sys/contrib/dev/acpica/   (props changed)
  stable/8/sys/contrib/pf/   (props changed)
  stable/8/sys/dev/xen/xenpci/   (props changed)

Modified: stable/8/sys/netipsec/xform_ipcomp.c
==============================================================================
--- stable/8/sys/netipsec/xform_ipcomp.c	Sat Dec  5 19:01:50 2009	(r200140)
+++ stable/8/sys/netipsec/xform_ipcomp.c	Sat Dec  5 19:03:20 2009	(r200141)
@@ -343,6 +343,17 @@ ipcomp_output(
 	ipcompx = sav->tdb_compalgxform;
 	IPSEC_ASSERT(ipcompx != NULL, ("null compression xform"));
 
+	/*
+	 * Do not touch the packet in case our payload to compress
+	 * is lower than the minimal threshold of the compression
+	 * alogrithm.  We will just send out the data uncompressed.
+	 * See RFC 3173, 2.2. Non-Expansion Policy.
+	 */
+	if (m->m_pkthdr.len <= ipcompx->minlen) {
+		/* XXX-BZ V_ipcompstat.threshold++; */
+		return ipsec_process_done(m, isr);
+	}
+
 	ralen = m->m_pkthdr.len - skip;	/* Raw payload length before comp. */
 	hlen = IPCOMP_HLENGTH;