From: Remi Gacogne <remi.gacogne@powerdns.com>
Date: Wed, 9 Jun 2021 10:07:42 +0000 (+0200)
Subject: dnsdist: Fix an tx ID endianess issue for DoH -> truncated UDP -> TCP
X-Git-Tag: dnsdist-1.7.0-alpha1~45^2~11
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8ac88d69894a4bc54bb93ff9519aca424e58b6f9;p=thirdparty%2Fpdns.git

dnsdist: Fix an tx ID endianess issue for DoH -> truncated UDP -> TCP
---

diff --git a/pdns/dnsdist-idstate.hh b/pdns/dnsdist-idstate.hh
index 76afc52df8..5d991042fd 100644
--- a/pdns/dnsdist-idstate.hh
+++ b/pdns/dnsdist-idstate.hh
@@ -258,6 +258,7 @@ struct IDState
 #endif
   uint16_t qtype{0}; // 2
   uint16_t qclass{0}; // 2
+  // origID is in network-byte order
   uint16_t origID{0}; // 2
   uint16_t origFlags{0}; // 2
   uint16_t cacheFlags{0}; // DNS flags as sent to the backend // 2
diff --git a/pdns/dnsdist-tcp.cc b/pdns/dnsdist-tcp.cc
index cb40ce90da..7673eaacc6 100644
--- a/pdns/dnsdist-tcp.cc
+++ b/pdns/dnsdist-tcp.cc
@@ -586,7 +586,7 @@ static void handleQuery(std::shared_ptr<IncomingTCPConnectionState>& state, cons
 
   IDState ids;
   setIDStateFromDNSQuestion(ids, dq, std::move(qname));
-  ids.origID = ntohs(dh->id);
+  ids.origID = dh->id;
 
   prependSizeToTCPQuery(state->d_buffer, 0);
 
diff --git a/pdns/dnsdistdist/dnsdist-tcp-downstream.cc b/pdns/dnsdistdist/dnsdist-tcp-downstream.cc
index 560a26ebdb..41a5b47318 100644
--- a/pdns/dnsdistdist/dnsdist-tcp-downstream.cc
+++ b/pdns/dnsdistdist/dnsdist-tcp-downstream.cc
@@ -67,8 +67,8 @@ IOState TCPConnectionToBackend::sendQuery(std::shared_ptr<TCPConnectionToBackend
   conn->incQueries();
   conn->d_currentPos = 0;
 
-  DEBUGLOG("adding a pending response for ID "<<conn->d_currentQuery.d_idstate.origID<<" and QNAME "<<conn->d_currentQuery.d_idstate.qname);
-  conn->d_pendingResponses[conn->d_currentQuery.d_idstate.origID] = std::move(conn->d_currentQuery);
+  DEBUGLOG("adding a pending response for ID "<<ntohs(conn->d_currentQuery.d_idstate.origID)<<" and QNAME "<<conn->d_currentQuery.d_idstate.qname);
+  conn->d_pendingResponses[ntohs(conn->d_currentQuery.d_idstate.origID)] = std::move(conn->d_currentQuery);
   conn->d_currentQuery.d_buffer.clear();
 
   ++conn->d_ds->outstanding;
diff --git a/pdns/dnsdistdist/doh.cc b/pdns/dnsdistdist/doh.cc
index a2d7ef3a46..fae4dbbe73 100644
--- a/pdns/dnsdistdist/doh.cc
+++ b/pdns/dnsdistdist/doh.cc
@@ -1291,7 +1291,7 @@ static void on_dnsdist(h2o_socket_t *listener, const char *err)
   if (!du->tcp && du->truncated && du->response.size() > sizeof(dnsheader)) {
     /* restoring the original ID */
     dnsheader* queryDH = reinterpret_cast<struct dnsheader*>(du->query.data() + du->proxyProtocolPayloadSize);
-    queryDH->id = htons(du->ids.origID);
+    queryDH->id = du->ids.origID;
 
     auto cpq = std::make_unique<DoHCrossProtocolQuery>(du);
 
diff --git a/regression-tests.dnsdist/test_DOH.py b/regression-tests.dnsdist/test_DOH.py
index 64439f8899..1685065fc2 100644
--- a/regression-tests.dnsdist/test_DOH.py
+++ b/regression-tests.dnsdist/test_DOH.py
@@ -999,9 +999,9 @@ class TestDOHWithCache(DNSDistDOHTest):
         # backend, then over TCP
         name = 'truncated-udp.doh-with-cache.tests.powerdns.com.'
         query = dns.message.make_query(name, 'A', 'IN')
-        query.id = 0
+        query.id = 42
         expectedQuery = dns.message.make_query(name, 'A', 'IN', use_edns=True, payload=4096)
-        expectedQuery.id = 0
+        expectedQuery.id = 42
         response = dns.message.make_response(query)
         rrset = dns.rrset.from_text(name,
                                     3600,