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/* SPDX-License-Identifier: LGPL-2.1-or-later */
#pragma once
#include "sd-bus.h"
#include "set.h"
#include "varlink.h"
typedef struct DnsQueryCandidate DnsQueryCandidate;
typedef struct DnsQuery DnsQuery;
typedef struct DnsStubListenerExtra DnsStubListenerExtra;
#include "resolved-dns-answer.h"
#include "resolved-dns-question.h"
#include "resolved-dns-search-domain.h"
#include "resolved-dns-transaction.h"
struct DnsQueryCandidate {
unsigned n_ref;
int error_code;
DnsQuery *query;
DnsScope *scope;
DnsSearchDomain *search_domain;
Set *transactions;
LIST_FIELDS(DnsQueryCandidate, candidates_by_query);
LIST_FIELDS(DnsQueryCandidate, candidates_by_scope);
};
struct DnsQuery {
Manager *manager;
/* 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.
*
* Note that questions may consist of multiple RR keys at once, but they must be for the same domain
* name. This is used for A+AAAA and TXT+SRV lookups: we'll allocate a single DnsQuery object for
* them instead of two separate ones. That allows us minor optimizations with response handling:
* CNAME/DNAMEs of the first reply we get can already be used to follow the CNAME/DNAME chain for
* both, and we can take benefit of server replies that oftentimes put A responses into AAAA queries
* and vice versa (in the additional section). */
DnsQuestion *question_idna;
DnsQuestion *question_utf8;
/* If this is not a question by ourselves, but a "bypass" request, we propagate the original packet
* here, and use that instead. */
DnsPacket *question_bypass;
/* When we follow a CNAME redirect, we save the original question here, for informational/monitoring
* purposes. We'll keep adding to this whenever we go one step in the redirect, so that in the end
* this will contain the complete set of CNAME questions. */
DnsQuestion *collected_questions;
uint64_t flags;
int ifindex;
/* 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. */
int auxiliary_result;
DnsQuery *auxiliary_for;
LIST_HEAD(DnsQuery, auxiliary_queries);
LIST_HEAD(DnsQueryCandidate, candidates);
sd_event_source *timeout_event_source;
/* Discovered data */
DnsAnswer *answer;
int answer_rcode;
DnssecResult answer_dnssec_result;
uint64_t answer_query_flags;
DnsProtocol answer_protocol;
int answer_family;
DnsPacket *answer_full_packet;
DnsSearchDomain *answer_search_domain;
DnsTransactionState state;
int answer_errno; /* if state is DNS_TRANSACTION_ERRNO */
unsigned block_ready;
uint8_t n_auxiliary_queries;
uint8_t n_cname_redirects;
bool previous_redirect_unauthenticated:1;
bool previous_redirect_non_confidential:1;
bool previous_redirect_non_synthetic:1;
bool request_address_valid:1;
/* Bus + Varlink client information */
sd_bus_message *bus_request;
Varlink *varlink_request;
int request_family;
union in_addr_union request_address;
unsigned block_all_complete;
char *request_address_string;
/* DNS stub information */
DnsPacket *request_packet;
DnsStream *request_stream;
DnsAnswer *reply_answer;
DnsAnswer *reply_authoritative;
DnsAnswer *reply_additional;
DnsStubListenerExtra *stub_listener_extra;
/* Completion callback */
void (*complete)(DnsQuery* q);
sd_bus_track *bus_track;
LIST_FIELDS(DnsQuery, queries);
LIST_FIELDS(DnsQuery, auxiliary_queries);
/* Note: fields should be ordered to minimize alignment gaps. Use pahole! */
};
enum {
DNS_QUERY_MATCH,
DNS_QUERY_NOMATCH,
DNS_QUERY_CNAME,
};
DnsQueryCandidate* dns_query_candidate_ref(DnsQueryCandidate*);
DnsQueryCandidate* dns_query_candidate_unref(DnsQueryCandidate*);
DEFINE_TRIVIAL_CLEANUP_FUNC(DnsQueryCandidate*, dns_query_candidate_unref);
void dns_query_candidate_notify(DnsQueryCandidate *c);
int dns_query_new(Manager *m, DnsQuery **q, DnsQuestion *question_utf8, DnsQuestion *question_idna, DnsPacket *question_bypass, 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_one(DnsQuery *q);
int dns_query_process_cname_many(DnsQuery *q);
void dns_query_complete(DnsQuery *q, DnsTransactionState state);
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);
bool dns_query_fully_authenticated(DnsQuery *q);
bool dns_query_fully_confidential(DnsQuery *q);
bool dns_query_fully_authoritative(DnsQuery *q);
static inline uint64_t dns_query_reply_flags_make(DnsQuery *q) {
assert(q);
return SD_RESOLVED_FLAGS_MAKE(q->answer_protocol,
q->answer_family,
dns_query_fully_authenticated(q),
dns_query_fully_confidential(q)) |
(q->answer_query_flags & (SD_RESOLVED_FROM_MASK|SD_RESOLVED_SYNTHETIC));
}
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