edns_cookies extension

src/request-internal.c

@@ -209,6 +209,8 @@ dns_req_new(getdns_context *context, getdns_eventloop *loop,
 	    =  is_extension_set(extensions, "dnssec_return_validation_chain");
 	int dnssec_ok_checking_disabled
 	    =  is_extension_set(extensions, "dnssec_ok_checking_disabled");
+	int edns_cookies
+	    =  is_extension_set(extensions, "edns_cookies");
 
 	int dnssec_extension_set = dnssec_return_status
 	    || dnssec_return_only_secure || dnssec_return_validation_chain
@@ -281,7 +283,8 @@ dns_req_new(getdns_context *context, getdns_eventloop *loop,
 		(void) getdns_list_get_length(options, &noptions);
 
 	with_opt = edns_do_bit != 0 || edns_maximum_udp_payload_size != 512 ||
-	    edns_extended_rcode != 0 || edns_version != 0 || noptions;
+	    edns_extended_rcode != 0 || edns_version != 0 || noptions ||
+	    edns_cookies;
 
 	edns_maximum_udp_payload_size = with_opt &&
 	    ( edns_maximum_udp_payload_size == -1 ||
@@ -307,6 +310,12 @@ dns_req_new(getdns_context *context, getdns_eventloop *loop,
 		max_query_sz = ( GLDNS_HEADER_SIZE
 		    + strlen(name) + 1 + 4 /* dname always smaller then strlen(name) + 1 */
 		    + 12 + opt_options_size /* space needed for OPT (if needed) */
+		    + ( !edns_cookies ? 0
+		      :  2 /* EDNS0 Option Code */
+		      +  2 /* Option length = 8 + 16 = 24 */
+		      +  8 /* client cookie */
+		      + 16 /* server cookie */
+		      )
 		    /* TODO: TSIG */
 		    + 7) / 8 * 8;
 	}
@@ -343,6 +352,7 @@ dns_req_new(getdns_context *context, getdns_eventloop *loop,
 	result->dnssec_return_status           = dnssec_return_status;
 	result->dnssec_return_only_secure      = dnssec_return_only_secure;
 	result->dnssec_return_validation_chain = dnssec_return_validation_chain;
+	result->edns_cookies                   = edns_cookies;
 
 	/* will be set by caller */
 	result->user_pointer = NULL;

src/types-internal.h

@@ -46,6 +46,7 @@ struct getdns_context;
 struct getdns_upstreams;
 struct getdns_upstream;
 
+#define EDNSCOOKIE_OPCODE 65001
 
 /**
  * \defgroup strings String Constants
@@ -238,6 +239,7 @@ typedef struct getdns_dns_req {
 	int dnssec_return_status;
 	int dnssec_return_only_secure;
 	int dnssec_return_validation_chain;
+	int edns_cookies;
 
 	/* Internally used by return_validation_chain */
 	int dnssec_ok_checking_disabled;

src/util-internal.c

@@ -64,6 +64,9 @@ static getdns_extension_format extformats[] = {
 	{"dnssec_return_only_secure", t_int},
 	{"dnssec_return_status", t_int},
 	{"dnssec_return_validation_chain", t_int},
+#ifdef EDNS_COOKIES
+	{"edns_cookies", t_int},
+#endif
 	{"return_api_information", t_int},
 	{"return_both_v4_and_v6", t_int},
 	{"return_call_debugging", t_int},