resolved: fix the rcode to SUCCESS if we find at least one matching RR in a DNS response

[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 aa2823cfb9daecec941dfa4397dc6d2b490d2642..c53431576b82ee6b5aa97fa7c95739ef841d87a6 100644 (file)
--- a/src/resolve/resolved-dns-packet.h
+++ b/src/resolve/resolved-dns-packet.h
@@ -76,10 +76,12 @@ struct DnsPacket {
         size_t size, allocated, rindex;
         void *_data; /* don't access directly, use DNS_PACKET_DATA()! */
         Hashmap *names; /* For name compression */
+        size_t opt_start, opt_size;
 
         /* Parsed data */
         DnsQuestion *question;
         DnsAnswer *answer;
+        DnsResourceRecord *opt;
 
         /* Packet reception metadata */
         int ifindex;
@@ -88,6 +90,9 @@ struct DnsPacket {
         uint16_t sender_port, destination_port;
         uint32_t ttl;
 
+        /* For support of truncated packets */
+        DnsPacket *more;
+
         bool on_stack:1;
         bool extracted:1;
         bool refuse_compression:1;
@@ -114,7 +119,17 @@ 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)
@@ -146,6 +161,8 @@ static inline unsigned DNS_PACKET_RRCOUNT(DnsPacket *p) {
 int dns_packet_new(DnsPacket **p, DnsProtocol protocol, size_t mtu);
 int dns_packet_new_query(DnsPacket **p, DnsProtocol protocol, size_t mtu, bool dnssec_checking_disabled);
 
+void dns_packet_set_flags(DnsPacket *p, bool dnssec_checking_disabled, bool truncated);
+
 DnsPacket *dns_packet_ref(DnsPacket *p);
 DnsPacket *dns_packet_unref(DnsPacket *p);
 
@@ -155,19 +172,22 @@ int dns_packet_validate(DnsPacket *p);
 int dns_packet_validate_reply(DnsPacket *p);
 int dns_packet_validate_query(DnsPacket *p);
 
+int dns_packet_is_reply_for(DnsPacket *p, const DnsResourceKey *key);
+
 int dns_packet_append_blob(DnsPacket *p, const void *d, size_t sz, size_t *start);
 int dns_packet_append_uint8(DnsPacket *p, uint8_t v, size_t *start);
 int dns_packet_append_uint16(DnsPacket *p, uint16_t v, size_t *start);
 int dns_packet_append_uint32(DnsPacket *p, uint32_t v, size_t *start);
 int dns_packet_append_string(DnsPacket *p, const char *s, size_t *start);
 int dns_packet_append_raw_string(DnsPacket *p, const void *s, size_t size, size_t *start);
-int dns_packet_append_label(DnsPacket *p, const char *s, size_t l, size_t *start);
-int dns_packet_append_name(DnsPacket *p, const char *name, bool allow_compression, size_t *start);
+int dns_packet_append_label(DnsPacket *p, const char *s, size_t l, bool canonical_candidate, size_t *start);
+int dns_packet_append_name(DnsPacket *p, const char *name, bool allow_compression, bool canonical_candidate, size_t *start);
 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_rr(DnsPacket *p, uint16_t max_udp_size, bool edns0_do, size_t *start);
+int dns_packet_append_opt(DnsPacket *p, uint16_t max_udp_size, bool edns0_do, size_t *start);
 
 void dns_packet_truncate(DnsPacket *p, size_t sz);
+int dns_packet_truncate_opt(DnsPacket *p);
 
 int dns_packet_read(DnsPacket *p, size_t sz, const void **ret, size_t *start);
 int dns_packet_read_blob(DnsPacket *p, void *d, size_t sz, size_t *start);
@@ -177,8 +197,8 @@ int dns_packet_read_uint32(DnsPacket *p, uint32_t *ret, size_t *start);
 int dns_packet_read_string(DnsPacket *p, char **ret, size_t *start);
 int dns_packet_read_raw_string(DnsPacket *p, const void **ret, size_t *size, size_t *start);
 int dns_packet_read_name(DnsPacket *p, char **ret, bool allow_compression, size_t *start);
-int dns_packet_read_key(DnsPacket *p, DnsResourceKey **ret, size_t *start);
-int dns_packet_read_rr(DnsPacket *p, DnsResourceRecord **ret, size_t *start);
+int dns_packet_read_key(DnsPacket *p, DnsResourceKey **ret, bool *ret_cache_flush, size_t *start);
+int dns_packet_read_rr(DnsPacket *p, DnsResourceRecord **ret, bool *ret_cache_flush, size_t *start);
 
 void dns_packet_rewind(DnsPacket *p, size_t idx);
 
@@ -193,6 +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,
@@ -225,6 +246,9 @@ DnsProtocol dns_protocol_from_string(const char *s) _pure_;
 #define LLMNR_MULTICAST_IPV4_ADDRESS ((struct in_addr) { .s_addr = htobe32(224U << 24 | 252U) })
 #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, 0x00, 0x00, 0xfb } })
+
 static inline uint64_t SD_RESOLVED_FLAGS_MAKE(DnsProtocol protocol, int family, bool authenticated) {
         uint64_t f;
 
@@ -239,6 +263,9 @@ static inline uint64_t SD_RESOLVED_FLAGS_MAKE(DnsProtocol protocol, int family,
         case DNS_PROTOCOL_LLMNR:
                 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;
+
         default:
                 break;
         }