-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
+/* SPDX-License-Identifier: LGPL-2.1+ */
#pragma once
-/***
- This file is part of systemd.
-
- Copyright 2014 Lennart Poettering
-
- systemd is free software; you can redistribute it and/or modify it
- under the terms of the GNU Lesser General Public License as published by
- the Free Software Foundation; either version 2.1 of the License, or
- (at your option) any later version.
-
- systemd is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public License
- along with systemd; If not, see <http://www.gnu.org/licenses/>.
-***/
+#include "sd-event.h"
typedef struct DnsTransaction DnsTransaction;
typedef enum DnsTransactionState DnsTransactionState;
typedef enum DnsTransactionSource DnsTransactionSource;
+#include "resolved-dns-answer.h"
+#include "resolved-dns-dnssec.h"
+#include "resolved-dns-packet.h"
+#include "resolved-dns-question.h"
+#include "resolved-dns-server.h"
+
enum DnsTransactionState {
DNS_TRANSACTION_NULL,
DNS_TRANSACTION_PENDING,
_DNS_TRANSACTION_SOURCE_INVALID = -1
};
-#include "resolved-dns-answer.h"
-#include "resolved-dns-packet.h"
-#include "resolved-dns-question.h"
-#include "resolved-dns-scope.h"
-
struct DnsTransaction {
DnsScope *scope;
DnsResourceKey *key;
- char *key_string;
DnsTransactionState state;
bool initial_jitter_scheduled:1;
bool initial_jitter_elapsed:1;
+ bool clamp_ttl:1;
+
+ bool probing:1;
+
DnsPacket *sent, *received;
DnsAnswer *answer;
sd_event_source *timeout_event_source;
unsigned n_attempts;
+ unsigned n_picked_servers;
+
/* UDP connection logic, if we need it */
int dns_udp_fd;
sd_event_source *dns_udp_event_source;
/* The features of the DNS server at time of transaction start */
DnsServerFeatureLevel current_feature_level;
+ /* If we got SERVFAIL back, we retry the lookup, using a lower feature level than we used before. */
+ DnsServerFeatureLevel clamp_feature_level;
+
/* Query candidates this transaction is referenced by and that
* shall be notified about this specific transaction
* completing. */
- Set *notify_query_candidates;
+ Set *notify_query_candidates, *notify_query_candidates_done;
/* Zone items this transaction is referenced by and that shall
* be notified about completion. */
- Set *notify_zone_items;
+ Set *notify_zone_items, *notify_zone_items_done;
/* Other transactions that this transactions is referenced by
* and that shall be notified about completion. This is used
* when transactions want to validate their RRsets, but need
* another DNSKEY or DS RR to do so. */
- Set *notify_transactions;
+ Set *notify_transactions, *notify_transactions_done;
/* The opposite direction: the transactions this transaction
* created in order to request DNSKEY or DS RRs. */
unsigned block_gc;
LIST_FIELDS(DnsTransaction, transactions_by_scope);
+ LIST_FIELDS(DnsTransaction, transactions_by_stream);
};
int dns_transaction_new(DnsTransaction **ret, DnsScope *s, DnsResourceKey *key);
DnsTransaction* dns_transaction_free(DnsTransaction *t);
bool dns_transaction_gc(DnsTransaction *t);
+DEFINE_TRIVIAL_CLEANUP_FUNC(DnsTransaction*, dns_transaction_gc);
+
int dns_transaction_go(DnsTransaction *t);
void dns_transaction_process_reply(DnsTransaction *t, DnsPacket *p);
int dns_transaction_validate_dnssec(DnsTransaction *t);
int dns_transaction_request_dnssec_keys(DnsTransaction *t);
-const char *dns_transaction_key_string(DnsTransaction *t);
-
const char* dns_transaction_state_to_string(DnsTransactionState p) _const_;
DnsTransactionState dns_transaction_state_from_string(const char *s) _pure_;
#define MDNS_JITTER_MIN_USEC (20 * USEC_PER_MSEC)
#define MDNS_JITTER_RANGE_USEC (100 * USEC_PER_MSEC)
+/* mDNS probing interval, see RFC 6762 Section 8.1 */
+#define MDNS_PROBING_INTERVAL_USEC (250 * USEC_PER_MSEC)
+
/* Maximum attempts to send DNS requests, across all DNS servers */
-#define DNS_TRANSACTION_ATTEMPTS_MAX 16
+#define DNS_TRANSACTION_ATTEMPTS_MAX 24
/* Maximum attempts to send LLMNR requests, see RFC 4795 Section 2.7 */
#define LLMNR_TRANSACTION_ATTEMPTS_MAX 3
-#define TRANSACTION_ATTEMPTS_MAX(p) ((p) == DNS_PROTOCOL_LLMNR ? LLMNR_TRANSACTION_ATTEMPTS_MAX : DNS_TRANSACTION_ATTEMPTS_MAX)
+/* Maximum attempts to send MDNS requests, see RFC 6762 Section 8.1 */
+#define MDNS_TRANSACTION_ATTEMPTS_MAX 3
+
+#define TRANSACTION_ATTEMPTS_MAX(p) (((p) == DNS_PROTOCOL_LLMNR) ? \
+ LLMNR_TRANSACTION_ATTEMPTS_MAX : \
+ (((p) == DNS_PROTOCOL_MDNS) ? \
+ MDNS_TRANSACTION_ATTEMPTS_MAX : \
+ DNS_TRANSACTION_ATTEMPTS_MAX))