along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
-#include <netinet/udp.h>
#include <netinet/ip.h>
+#include <netinet/udp.h>
-#include "macro.h"
-#include "sparse-endian.h"
#include "hashmap.h"
#include "in-addr-util.h"
+#include "macro.h"
+#include "sparse-endian.h"
typedef struct DnsPacketHeader DnsPacketHeader;
typedef struct DnsPacket DnsPacket;
-#include "resolved-dns-rr.h"
-#include "resolved-dns-question.h"
-#include "resolved-dns-answer.h"
#include "resolved-def.h"
+#include "resolved-dns-answer.h"
+#include "resolved-dns-question.h"
+#include "resolved-dns-rr.h"
typedef enum DnsProtocol {
DNS_PROTOCOL_DNS,
/* RFC 1035 say 512 is the maximum, for classic unicast DNS */
#define DNS_PACKET_UNICAST_SIZE_MAX 512
+/* With EDNS0 we can use larger packets, default to 4096, which is what is commonly used */
+#define DNS_PACKET_UNICAST_SIZE_LARGE_MAX 4096
+
#define DNS_PACKET_SIZE_START 512
struct DnsPacket {
DnsQuestion *question;
DnsAnswer *answer;
- /* Packet reception meta data */
+ /* Packet reception metadata */
int ifindex;
int family, ipproto;
union in_addr_union sender, destination;
uint32_t ttl;
bool extracted;
+ bool refuse_compression;
};
static inline uint8_t* DNS_PACKET_DATA(DnsPacket *p) {
#define DNS_PACKET_ARCOUNT(p) be16toh(DNS_PACKET_HEADER(p)->arcount)
#define DNS_PACKET_MAKE_FLAGS(qr, opcode, aa, tc, rd, ra, ad, cd, rcode) \
- (((uint16_t) !!qr << 15) | \
- ((uint16_t) (opcode & 15) << 11) | \
- ((uint16_t) !!aa << 10) | \
- ((uint16_t) !!tc << 9) | \
- ((uint16_t) !!rd << 8) | \
- ((uint16_t) !!ra << 7) | \
- ((uint16_t) !!ad << 5) | \
- ((uint16_t) !!cd << 4) | \
- ((uint16_t) (rcode & 15)))
+ (((uint16_t) !!(qr) << 15) | \
+ ((uint16_t) ((opcode) & 15) << 11) | \
+ ((uint16_t) !!(aa) << 10) | /* on LLMNR: c */ \
+ ((uint16_t) !!(tc) << 9) | \
+ ((uint16_t) !!(rd) << 8) | /* on LLMNR: t */ \
+ ((uint16_t) !!(ra) << 7) | \
+ ((uint16_t) !!(ad) << 5) | \
+ ((uint16_t) !!(cd) << 4) | \
+ ((uint16_t) ((rcode) & 15)))
static inline unsigned DNS_PACKET_RRCOUNT(DnsPacket *p) {
return
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_name(DnsPacket *p, const char *name, bool allow_compression, 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);
+int dns_packet_append_opt_rr(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_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);
int dns_packet_read_uint16(DnsPacket *p, uint16_t *ret, size_t *start);
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_name(DnsPacket *p, char **ret,
- bool allow_compression, 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_skip_question(DnsPacket *p);
int dns_packet_extract(DnsPacket *p);
+static inline bool DNS_PACKET_SHALL_CACHE(DnsPacket *p) {
+ /* Never cache data originating from localhost, under the
+ * assumption, that it's coming from a locally DNS forwarder
+ * or server, that is caching on its own. */
+
+ return in_addr_is_localhost(p->family, &p->sender) == 0;
+}
+
enum {
DNS_RCODE_SUCCESS = 0,
DNS_RCODE_FORMERR = 1,
#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 DNSKEY_FLAG_ZONE_KEY (1u << 8)
-#define DNSKEY_FLAG_SEP (1u << 0)
-
-static inline uint16_t dnskey_to_flags(const DnsResourceRecord *rr) {
- return (rr->dnskey.zone_key_flag * DNSKEY_FLAG_ZONE_KEY |
- rr->dnskey.sep_flag * DNSKEY_FLAG_SEP);
-}
+#define DNSKEY_FLAG_ZONE_KEY (UINT16_C(1) << 8)
+#define DNSKEY_FLAG_SEP (UINT16_C(1) << 0)
-/* http://tools.ietf.org/html/rfc4034#appendix-A.1 */
+/* http://tools.ietf.org/html/rfc4034#appendix-A.1 and
+ * https://www.iana.org/assignments/dns-sec-alg-numbers/dns-sec-alg-numbers.xhtml */
enum {
DNSSEC_ALGORITHM_RSAMD5 = 1,
DNSSEC_ALGORITHM_DH,
DNSSEC_ALGORITHM_DSA,
DNSSEC_ALGORITHM_ECC,
DNSSEC_ALGORITHM_RSASHA1,
+ DNSSEC_ALGORITHM_DSA_NSEC3_SHA1,
+ DNSSEC_ALGORITHM_RSASHA1_NSEC3_SHA1,
+ DNSSEC_ALGORITHM_RSASHA256 = 8, /* RFC 5702 */
+ DNSSEC_ALGORITHM_RSASHA512 = 10, /* RFC 5702 */
DNSSEC_ALGORITHM_INDIRECT = 252,
DNSSEC_ALGORITHM_PRIVATEDNS,
DNSSEC_ALGORITHM_PRIVATEOID,
const char* dnssec_algorithm_to_string(int i) _const_;
int dnssec_algorithm_from_string(const char *s) _pure_;
+/* https://www.iana.org/assignments/ds-rr-types/ds-rr-types.xhtml */
+enum {
+ DNSSEC_DIGEST_SHA1 = 1,
+ DNSSEC_DIGEST_SHA256 = 2,
+ _DNSSEC_DIGEST_MAX_DEFINED
+};
+
+const char *dnssec_digest_to_string(int i) _const_;
+int dnssec_digest_from_string(const char *s) _pure_;
+
static inline uint64_t SD_RESOLVED_FLAGS_MAKE(DnsProtocol protocol, int family) {
/* Converts a protocol + family into a flags field as used in queries */
- if (protocol == DNS_PROTOCOL_DNS)
+ switch (protocol) {
+ case DNS_PROTOCOL_DNS:
return SD_RESOLVED_DNS;
- if (protocol == DNS_PROTOCOL_LLMNR)
+ case DNS_PROTOCOL_LLMNR:
return family == AF_INET6 ? SD_RESOLVED_LLMNR_IPV6 : SD_RESOLVED_LLMNR_IPV4;
+ default:
+ break;
+ }
+
return 0;
}
projects / thirdparty / systemd.git / blobdiff