From: Lennart Poettering <lennart@poettering.net>
Date: Thu, 7 Jan 2016 11:42:48 +0000 (+0100)
Subject: resolved: be less strict where the OPT pseudo-RR is placed
X-Git-Tag: v229~151^2~35
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=35b011ed7c108b3e3c67f641afdf75ca6c5a621e;p=thirdparty%2Fsystemd.git

resolved: be less strict where the OPT pseudo-RR is placed

This increases compatibility with crappy Belkin routers.
---

diff --git a/src/resolve/resolved-dns-packet.c b/src/resolve/resolved-dns-packet.c
index 4750bf1f5db..8a360a29fbe 100644
--- a/src/resolve/resolved-dns-packet.c
+++ b/src/resolve/resolved-dns-packet.c
@@ -2089,11 +2089,12 @@ int dns_packet_extract(DnsPacket *p) {
                                         goto finish;
                                 }
 
-                                /* The OPT RR is only valid in the Additional section */
-                                if (i < DNS_PACKET_ANCOUNT(p) + DNS_PACKET_NSCOUNT(p)) {
-                                        r = -EBADMSG;
-                                        goto finish;
-                                }
+                                /* Note that we accept the OPT RR in
+                                 * any section, not just in the
+                                 * additional section, as some routers
+                                 * (Belkin!)  blindly copy the OPT RR
+                                 * from the query to the reply packet,
+                                 * and don't get the section right. */
 
                                 /* Two OPT RRs? */
                                 if (p->opt) {