ldns-testns match on edns0 udp_size

examples/ldns-testpkts.c

@@ -130,6 +130,13 @@ static void matchline(char* line, struct entry* e)
 			e->ixfr_soa_serial = (uint32_t)strtol(parse, (char**)&parse, 10);
 			while(isspace((int)*parse)) 
 				parse++;
+		} else if(str_keyword(&parse, "udp_size")) {
+			if(*parse != '=' && *parse != ':')
+				error("expected = or : in MATCH: %s", line);
+			parse++;
+			e->match_udp_size = (uint32_t)strtol(parse, (char**)&parse, 10);
+			while(isspace((int)*parse)) 
+				parse++;
 		} else {
 			error("could not parse MATCH: '%s'", parse);
 		}
@@ -243,6 +250,7 @@ static struct entry* new_entry(void)
 	e->match_serial = false;
 	e->ixfr_soa_serial = 0;
 	e->match_transport = transport_any;
+	e->match_udp_size = 0;
 	e->reply_list = NULL;
 	e->copy_id = false;
 	e->copy_query = false;
@@ -795,6 +803,12 @@ find_match(struct entry* entries, ldns_pkt* query_pkt,
 			verbose(3, "bad transport\n");
 			continue;
 		}
+		if(p->match_udp_size > 0 && transport == transport_udp && (
+			!ldns_pkt_edns(query_pkt) ||
+			ldns_pkt_edns_udp_size(query_pkt) < p->match_udp_size)) {
+			verbose(3, "bad udp_size\n");
+			continue;
+		}
 		if(p->match_all && !match_all(query_pkt, reply, p->match_ttl)) {
 			verbose(3, "bad allmatch\n");
 			continue;

examples/ldns-testpkts.h

@@ -49,6 +49,9 @@
 	; 'DO' will match only queries with DO bit set.
 	; 'noedns' matches queries without EDNS OPT records.
 	; 'ednsdata' matches queries to HEX_EDNS section.
+	; 'udp_size=1232' makes the query match if:
+	;   udp_size in query edns0 field >= 1232,
+	;   or the query came over TCP.
 	MATCH [opcode] [qtype] [qname] [serial=<value>] [all] [ttl]
 	MATCH [UDP|TCP] DO
 	MATCH ...
@@ -185,6 +188,8 @@ struct entry {
 	uint32_t ixfr_soa_serial; 
 	/** match on UDP/TCP */
 	enum transport_type match_transport; 
+	/** match on edns udp size (larger or equal) */
+	uint16_t match_udp_size;
 
 	/** pre canned reply */
 	struct reply_packet *reply_list;