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-rw-r--r--src/resolve/resolved-dns-packet.h112
1 files changed, 66 insertions, 46 deletions
diff --git a/src/resolve/resolved-dns-packet.h b/src/resolve/resolved-dns-packet.h
index fbbabaf232..c53431576b 100644
--- a/src/resolve/resolved-dns-packet.h
+++ b/src/resolve/resolved-dns-packet.h
@@ -21,21 +21,21 @@
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,
@@ -65,6 +65,9 @@ struct DnsPacketHeader {
/* 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 {
@@ -73,10 +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;
@@ -85,8 +90,13 @@ struct DnsPacket {
uint16_t sender_port, destination_port;
uint32_t ttl;
- bool extracted;
- bool refuse_compression;
+ /* For support of truncated packets */
+ DnsPacket *more;
+
+ bool on_stack:1;
+ bool extracted:1;
+ bool refuse_compression:1;
+ bool canonical_form:1;
};
static inline uint8_t* DNS_PACKET_DATA(DnsPacket *p) {
@@ -109,7 +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)
@@ -139,7 +159,9 @@ 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);
+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);
@@ -150,16 +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_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_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, 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);
+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);
+
+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);
@@ -167,16 +195,25 @@ int dns_packet_read_uint8(DnsPacket *p, uint8_t *ret, 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_key(DnsPacket *p, DnsResourceKey **ret, size_t *start);
-int dns_packet_read_rr(DnsPacket *p, DnsResourceRecord **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, 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);
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;
+}
+
+/* https://www.iana.org/assignments/dns-parameters/dns-parameters.xhtml#dns-parameters-6 */
enum {
DNS_RCODE_SUCCESS = 0,
DNS_RCODE_FORMERR = 1,
@@ -209,42 +246,25 @@ 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 DNSKEY_FLAG_ZONE_KEY (1u << 8)
-#define DNSKEY_FLAG_SEP (1u << 0)
+#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 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);
-}
+static inline uint64_t SD_RESOLVED_FLAGS_MAKE(DnsProtocol protocol, int family, bool authenticated) {
+ uint64_t f;
-/* http://tools.ietf.org/html/rfc4034#appendix-A.1 */
-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_INDIRECT = 252,
- DNSSEC_ALGORITHM_PRIVATEDNS,
- DNSSEC_ALGORITHM_PRIVATEOID,
- _DNSSEC_ALGORITHM_MAX_DEFINED
-};
+ /* Converts a protocol + family into a flags field as used in queries and responses */
-const char* dnssec_algorithm_to_string(int i) _const_;
-int dnssec_algorithm_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 */
+ f = authenticated ? SD_RESOLVED_AUTHENTICATED : 0;
switch (protocol) {
case DNS_PROTOCOL_DNS:
- return SD_RESOLVED_DNS;
+ return f|SD_RESOLVED_DNS;
case DNS_PROTOCOL_LLMNR:
- return family == AF_INET6 ? SD_RESOLVED_LLMNR_IPV6 : SD_RESOLVED_LLMNR_IPV4;
+ 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;
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2025-01-23 10:43:22 +0000