Systemd/src/resolve/resolved-dns-query.h
Lennart Poettering 17c8de633f resolved: when using the ResolveRecord() bus call, adjust TTL for caching time
When we return the full RR wire data, let's make sure the TTL included in it is
adjusted by the time the RR sat in the cache.

As an optimization we do this only for ResolveRecord() and not for
ResolveHostname() and friends, since adjusting the TTL means copying the RR
object, and we don#t want to do that if there's no reason to.
(ResolveHostname() and friends don't return the TTL hence there's no reason to
in that case)
2016-06-21 13:20:48 +02:00

138 lines
4.3 KiB
C

#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-bus.h"
#include "set.h"
typedef struct DnsQueryCandidate DnsQueryCandidate;
typedef struct DnsQuery DnsQuery;
#include "resolved-dns-answer.h"
#include "resolved-dns-question.h"
#include "resolved-dns-stream.h"
#include "resolved-dns-search-domain.h"
struct DnsQueryCandidate {
DnsQuery *query;
DnsScope *scope;
DnsSearchDomain *search_domain;
int error_code;
Set *transactions;
LIST_FIELDS(DnsQueryCandidate, candidates_by_query);
LIST_FIELDS(DnsQueryCandidate, candidates_by_scope);
};
struct DnsQuery {
Manager *manager;
/* When resolving a service, we first create a TXT+SRV query,
* and then for the hostnames we discover auxiliary A+AAAA
* queries. This pointer always points from the auxiliary
* queries back to the TXT+SRV query. */
DnsQuery *auxiliary_for;
LIST_HEAD(DnsQuery, auxiliary_queries);
unsigned n_auxiliary_queries;
int auxiliary_result;
/* The question, formatted in IDNA for use on classic DNS, and as UTF8 for use in LLMNR or mDNS. Note that even
* on classic DNS some labels might use UTF8 encoding. Specifically, DNS-SD service names (in contrast to their
* domain suffixes) use UTF-8 encoding even on DNS. Thus, the difference between these two fields is mostly
* relevant only for explicit *hostname* lookups as well as the domain suffixes of service lookups. */
DnsQuestion *question_idna;
DnsQuestion *question_utf8;
uint64_t flags;
int ifindex;
/* If true, A or AAAA RR lookups will be suppressed on links with no routable address of the matching address
* family */
bool suppress_unroutable_family;
/* If true, the RR TTLs of the answer will be clamped by their current left validity in the cache */
bool clamp_ttl;
DnsTransactionState state;
unsigned n_cname_redirects;
LIST_HEAD(DnsQueryCandidate, candidates);
sd_event_source *timeout_event_source;
/* Discovered data */
DnsAnswer *answer;
int answer_rcode;
DnssecResult answer_dnssec_result;
bool answer_authenticated;
DnsProtocol answer_protocol;
int answer_family;
DnsSearchDomain *answer_search_domain;
int answer_errno; /* if state is DNS_TRANSACTION_ERRNO */
/* Bus client information */
sd_bus_message *request;
int request_family;
bool request_address_valid;
union in_addr_union request_address;
unsigned block_all_complete;
char *request_address_string;
/* Completion callback */
void (*complete)(DnsQuery* q);
unsigned block_ready;
sd_bus_track *bus_track;
LIST_FIELDS(DnsQuery, queries);
LIST_FIELDS(DnsQuery, auxiliary_queries);
};
enum {
DNS_QUERY_MATCH,
DNS_QUERY_NOMATCH,
DNS_QUERY_RESTARTED,
};
DnsQueryCandidate* dns_query_candidate_free(DnsQueryCandidate *c);
void dns_query_candidate_notify(DnsQueryCandidate *c);
int dns_query_new(Manager *m, DnsQuery **q, DnsQuestion *question_utf8, DnsQuestion *question_idna, int family, uint64_t flags);
DnsQuery *dns_query_free(DnsQuery *q);
int dns_query_make_auxiliary(DnsQuery *q, DnsQuery *auxiliary_for);
int dns_query_go(DnsQuery *q);
void dns_query_ready(DnsQuery *q);
int dns_query_process_cname(DnsQuery *q);
int dns_query_bus_track(DnsQuery *q, sd_bus_message *m);
DnsQuestion* dns_query_question_for_protocol(DnsQuery *q, DnsProtocol protocol);
const char *dns_query_string(DnsQuery *q);
DEFINE_TRIVIAL_CLEANUP_FUNC(DnsQuery*, dns_query_free);