[TCP]: MTU probing

Implementation of packetization layer path mtu discovery for TCP, based on
the internet-draft currently found at
<http://www.ietf.org/internet-drafts/draft-ietf-pmtud-method-05.txt>.

Signed-off-by: John Heffner <jheffner@psc.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h
index 8ad4bea..6e8880e 100644
--- a/include/linux/sysctl.h
+++ b/include/linux/sysctl.h
@@ -397,6 +397,8 @@
 	NET_TCP_CONG_CONTROL=110,
 	NET_TCP_ABC=111,
 	NET_IPV4_IPFRAG_MAX_DIST=112,
+ 	NET_TCP_MTU_PROBING=113,
+	NET_TCP_BASE_MSS=114,
 };
 
 enum {