From: Denis Ovsienko <infrastation@yandex.ru>
Date: Tue, 27 Sep 2011 11:35:39 +0000 (+0400)
Subject: bgpd: ignore 4 bits of attribute flags byte
X-Git-Tag: frr-2.0-rc1~2013
X-Git-Url: https://git.puffer.fish/?a=commitdiff_plain;h=2d42e68aa032ed2f11471aee444935918d35c8bb;p=mirror%2Ffrr.git

bgpd: ignore 4 bits of attribute flags byte
---

diff --git a/bgpd/bgp_attr.c b/bgpd/bgp_attr.c
index aa4ce8f1e2..45a17fac36 100644
--- a/bgpd/bgp_attr.c
+++ b/bgpd/bgp_attr.c
@@ -1788,7 +1788,10 @@ bgp_attr_parse (struct peer *peer, struct attr *attr, bgp_size_t size,
 
       /* Fetch attribute flag and type. */
       startp = BGP_INPUT_PNT (peer);
-      flag = stream_getc (BGP_INPUT (peer));
+      /* "The lower-order four bits of the Attribute Flags octet are
+         unused.  They MUST be zero when sent and MUST be ignored when
+         received." */
+      flag = 0xF0 & stream_getc (BGP_INPUT (peer));
       type = stream_getc (BGP_INPUT (peer));
 
       /* Check whether Extended-Length applies and is in bounds */