Allow zone transfer in authoritative mode whenever auth-peer is specified.

CHANGELOG

@@ -29,6 +29,10 @@ version 2.80
 	have different parameters and avoids advertising the same
 	prefix twice. Thanks to Luis Marsano for spotting this case.
 
+	Allow zone transfer in authoritative mode if auth-peer is specified,
+	even if auth-sec-servers is not. Thanks to Raphaël Halimi for
+	the suggestion.
+
 
 version 2.79
 	Fix parsing of CNAME arguments, which are confused by extra spaces.

man/dnsmasq.8

@@ -817,7 +817,11 @@ authoritative zones as dnsmasq.
 Specify the addresses of secondary servers which are allowed to
 initiate zone transfer (AXFR) requests for zones for which dnsmasq is
 authoritative. If this option is not given, then AXFR requests will be
-accepted from any secondary. 
+accepted from any secondary. Specifying
+.B auth-peer
+without
+.B auth-sec-servers
+enables zone transfer but does not advertise the secondary in NS records returned by dnsmasq.
 .TP 
 .B --conntrack
 Read the Linux connection track mark associated with incoming DNS

src/auth.c

@@ -436,8 +436,9 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
 		if (sockaddr_isequal(peer_addr, &peers->addr))
 		  break;
 	      
-	      /* Refuse all AXFR unless --auth-sec-servers is set */
-	      if ((!peers && daemon->auth_peers) || !daemon->secondary_forward_server)
+	      /* Refuse all AXFR unless --auth-sec-servers or auth-peers is set */
+	      if ((!daemon->secondary_forward_server && !daemon->auth_peers) ||
+		  (daemon->auth_peers && !peers)) 
 		{
 		  if (peer_addr->sa.sa_family == AF_INET)
 		    inet_ntop(AF_INET, &peer_addr->in.sin_addr, daemon->addrbuff, ADDRSTRLEN);