svn commit: r355129 - head/sys/netipsec

[Andrey V. Elsukov]

Author: ae
Date: Wed Nov 27 10:24:46 2019
New Revision: 355129
URL: https://svnweb.freebsd.org/changeset/base/355129

Log:
  Add support for dummy ESP packets with next header field equal to
  IPPROTO_NONE.
  
  According to RFC4303 2.6 they should be silently dropped.
  
  Submitted by:	aurelien.cazuc.external_stormshield.eu
  MFC after:	10 days
  Sponsored by:	Stormshield
  Differential Revision:	https://reviews.freebsd.org/D22557

Modified:
  head/sys/netipsec/xform_esp.c

Modified: head/sys/netipsec/xform_esp.c
==============================================================================
--- head/sys/netipsec/xform_esp.c	Wed Nov 27 07:51:29 2019	(r355128)
+++ head/sys/netipsec/xform_esp.c	Wed Nov 27 10:24:46 2019	(r355129)
@@ -614,6 +614,13 @@ esp_input_cb(struct cryptop *crp)
 		}
 	}
 
+	/*
+	 * RFC4303 2.6:
+	 * Silently drop packet if next header field is IPPROTO_NONE.
+	 */
+	if (lastthree[2] == IPPROTO_NONE)
+		goto bad;
+
 	/* Trim the mbuf chain to remove trailing authenticator and padding */
 	m_adj(m, -(lastthree[1] + 2));