resolved: add dns_packet_add_{question,answer}() helper

[thirdparty/systemd.git] / src / resolve / resolved-dns-packet.h

diff --git a/src/resolve/resolved-dns-packet.h b/src/resolve/resolved-dns-packet.h
index a09ace5b7502391b9bf7839fa61e662748f51911..fe2b3862971d2609cec5602abb0a42dcf7cf73fe 100644 (file)
--- a/src/resolve/resolved-dns-packet.h
+++ b/src/resolve/resolved-dns-packet.h
@@ -1,5 +1,3 @@
-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
 #pragma once
 
 /***
@@ -119,7 +117,17 @@ static inline uint8_t* DNS_PACKET_DATA(DnsPacket *p) {
 #define DNS_PACKET_RA(p) ((be16toh(DNS_PACKET_HEADER(p)->flags) >> 7) & 1)
 #define DNS_PACKET_AD(p) ((be16toh(DNS_PACKET_HEADER(p)->flags) >> 5) & 1)
 #define DNS_PACKET_CD(p) ((be16toh(DNS_PACKET_HEADER(p)->flags) >> 4) & 1)
-#define DNS_PACKET_RCODE(p) (be16toh(DNS_PACKET_HEADER(p)->flags) & 15)
+
+static inline uint16_t DNS_PACKET_RCODE(DnsPacket *p) {
+        uint16_t rcode;
+
+        if (p->opt)
+                rcode = (uint16_t) (p->opt->ttl >> 24);
+        else
+                rcode = 0;
+
+        return rcode | (be16toh(DNS_PACKET_HEADER(p)->flags) & 15);
+}
 
 /* LLMNR defines some bits differently */
 #define DNS_PACKET_LLMNR_C(p) DNS_PACKET_AA(p)
@@ -175,6 +183,8 @@ int dns_packet_append_name(DnsPacket *p, const char *name, bool allow_compressio
 int dns_packet_append_key(DnsPacket *p, const DnsResourceKey *key, size_t *start);
 int dns_packet_append_rr(DnsPacket *p, const DnsResourceRecord *rr, size_t *start, size_t *rdata_start);
 int dns_packet_append_opt(DnsPacket *p, uint16_t max_udp_size, bool edns0_do, size_t *start);
+int dns_packet_append_question(DnsPacket *p, DnsQuestion *q);
+int dns_packet_append_answer(DnsPacket *p, DnsAnswer *a);
 
 void dns_packet_truncate(DnsPacket *p, size_t sz);
 int dns_packet_truncate_opt(DnsPacket *p);
@@ -203,6 +213,7 @@ static inline bool DNS_PACKET_SHALL_CACHE(DnsPacket *p) {
         return in_addr_is_localhost(p->family, &p->sender) == 0;
 }
 
+/* https://www.iana.org/assignments/dns-parameters/dns-parameters.xhtml#dns-parameters-6 */
 enum {
         DNS_RCODE_SUCCESS = 0,
         DNS_RCODE_FORMERR = 1,
@@ -236,7 +247,7 @@ DnsProtocol dns_protocol_from_string(const char *s) _pure_;
 #define LLMNR_MULTICAST_IPV6_ADDRESS ((struct in6_addr) { .s6_addr = { 0xFF, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x03 } })
 
 #define MDNS_MULTICAST_IPV4_ADDRESS  ((struct in_addr) { .s_addr = htobe32(224U << 24 | 251U) })
-#define MDNS_MULTICAST_IPV6_ADDRESS  ((struct in6_addr) { .s6_addr = { 0xFF, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0xfb } })
+#define MDNS_MULTICAST_IPV6_ADDRESS  ((struct in6_addr) { .s6_addr = { 0xFF, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xfb } })
 
 static inline uint64_t SD_RESOLVED_FLAGS_MAKE(DnsProtocol protocol, int family, bool authenticated) {
         uint64_t f;
@@ -253,11 +264,9 @@ static inline uint64_t SD_RESOLVED_FLAGS_MAKE(DnsProtocol protocol, int family,
                 return f|(family == AF_INET6 ? SD_RESOLVED_LLMNR_IPV6 : SD_RESOLVED_LLMNR_IPV4);
 
         case DNS_PROTOCOL_MDNS:
-                return family == AF_INET6 ? SD_RESOLVED_MDNS_IPV6 : SD_RESOLVED_MDNS_IPV4;
+                return f|(family == AF_INET6 ? SD_RESOLVED_MDNS_IPV6 : SD_RESOLVED_MDNS_IPV4);
 
         default:
-                break;
+                return f;
         }
-
-        return 0;
 }