-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
+/* SPDX-License-Identifier: LGPL-2.1+ */
/***
This file is part of systemd.
#include "alloc-util.h"
#include "dns-domain.h"
+#include "dns-type.h"
#include "hostname-util.h"
#include "local-addresses.h"
#include "resolved-dns-query.h"
#include "resolved-etc-hosts.h"
#include "string-util.h"
-/* How long to wait for the query in total */
-#define QUERY_TIMEOUT_USEC (30 * USEC_PER_SEC)
-
#define CNAME_MAX 8
#define QUERIES_MAX 2048
#define AUXILIARY_QUERIES_MAX 64
while ((t = set_steal_first(c->transactions))) {
set_remove(t->notify_query_candidates, c);
+ set_remove(t->notify_query_candidates_done, c);
dns_transaction_gc(t);
}
}
if (c->scope)
LIST_REMOVE(candidates_by_scope, c->scope->query_candidates, c);
- free(c);
-
- return NULL;
+ return mfree(c);
}
static int dns_query_candidate_next_search_domain(DnsQueryCandidate *c) {
assert(c);
- if (c->search_domain && c->search_domain->linked) {
+ if (c->search_domain && c->search_domain->linked)
next = c->search_domain->domains_next;
+ else
+ next = dns_scope_get_search_domains(c->scope);
+ for (;;) {
if (!next) /* We hit the end of the list */
return 0;
- } else {
- next = dns_scope_get_search_domains(c->scope);
+ if (!next->route_only)
+ break;
- if (!next) /* OK, there's nothing. */
- return 0;
+ /* Skip over route-only domains */
+ next = next->domains_next;
}
dns_search_domain_unref(c->search_domain);
if (r < 0)
goto gc;
+ r = set_ensure_allocated(&t->notify_query_candidates_done, NULL);
+ if (r < 0)
+ goto gc;
+
r = set_put(t->notify_query_candidates, c);
if (r < 0)
goto gc;
goto gc;
}
+ t->clamp_ttl = c->query->clamp_ttl;
return 1;
gc:
DnsTransaction *t;
Iterator i;
int r;
+ unsigned n = 0;
assert(c);
r = dns_transaction_go(t);
if (r < 0)
return r;
+
+ n++;
}
+ /* If there was nothing to start, then let's proceed immediately */
+ if (n == 0)
+ dns_query_candidate_notify(c);
+
return 0;
}
return state;
}
+static bool dns_query_candidate_is_routable(DnsQueryCandidate *c, uint16_t type) {
+ int family;
+
+ assert(c);
+
+ /* Checks whether the specified RR type matches an address family that is routable on the link(s) the scope of
+ * this candidate belongs to. Specifically, whether there's a routable IPv4 address on it if we query an A RR,
+ * or a routable IPv6 address if we query an AAAA RR. */
+
+ if (!c->query->suppress_unroutable_family)
+ return true;
+
+ if (c->scope->protocol != DNS_PROTOCOL_DNS)
+ return true;
+
+ family = dns_type_to_af(type);
+ if (family < 0)
+ return true;
+
+ if (c->scope->link)
+ return link_relevant(c->scope->link, family, false);
+ else
+ return manager_routable(c->scope->manager, family);
+}
+
static int dns_query_candidate_setup_transactions(DnsQueryCandidate *c) {
DnsQuestion *question;
DnsResourceKey *key;
/* Create one transaction per question key */
DNS_QUESTION_FOREACH(key, question) {
_cleanup_(dns_resource_key_unrefp) DnsResourceKey *new_key = NULL;
+ DnsResourceKey *qkey;
+
+ if (!dns_query_candidate_is_routable(c, key->type))
+ continue;
if (c->search_domain) {
r = dns_resource_key_new_append_suffix(&new_key, key, c->search_domain->name);
if (r < 0)
goto fail;
- }
- r = dns_query_candidate_add_transaction(c, new_key ?: key);
+ qkey = new_key;
+ } else
+ qkey = key;
+
+ if (!dns_scope_good_key(c->scope, qkey))
+ continue;
+
+ r = dns_query_candidate_add_transaction(c, qkey);
if (r < 0)
goto fail;
sd_bus_message_unref(q->request);
sd_bus_track_unref(q->bus_track);
+ dns_packet_unref(q->request_dns_packet);
+ dns_packet_unref(q->reply_dns_packet);
+
+ if (q->request_dns_stream) {
+ /* Detach the stream from our query, in case something else keeps a reference to it. */
+ q->request_dns_stream->complete = NULL;
+ q->request_dns_stream->on_packet = NULL;
+ q->request_dns_stream->query = NULL;
+ dns_stream_unref(q->request_dns_stream);
+ }
+
free(q->request_address_string);
if (q->manager) {
q->manager->n_dns_queries--;
}
- free(q);
-
- return NULL;
+ return mfree(q);
}
int dns_query_new(
DnsQuery **ret,
DnsQuestion *question_utf8,
DnsQuestion *question_idna,
- int ifindex, uint64_t flags) {
+ int ifindex,
+ uint64_t flags) {
_cleanup_(dns_query_freep) DnsQuery *q = NULL;
DnsResourceKey *key;
bool good = false;
int r;
+ char key_str[DNS_RESOURCE_KEY_STRING_MAX];
assert(m);
q->answer_family = AF_UNSPEC;
/* First dump UTF8 question */
- DNS_QUESTION_FOREACH(key, question_utf8) {
- _cleanup_free_ char *p = NULL;
-
- r = dns_resource_key_to_string(key, &p);
- if (r < 0)
- return r;
-
- log_debug("Looking up RR for %s.", strstrip(p));
- }
+ DNS_QUESTION_FOREACH(key, question_utf8)
+ log_debug("Looking up RR for %s.",
+ dns_resource_key_to_string(key, key_str, sizeof key_str));
/* And then dump the IDNA question, but only what hasn't been dumped already through the UTF8 question. */
DNS_QUESTION_FOREACH(key, question_idna) {
- _cleanup_free_ char *p = NULL;
-
r = dns_question_contains(question_utf8, key);
if (r < 0)
return r;
if (r > 0)
continue;
- r = dns_resource_key_to_string(key, &p);
- if (r < 0)
- return r;
-
- log_debug("Looking up IDNA RR for %s.", strstrip(p));
+ log_debug("Looking up IDNA RR for %s.",
+ dns_resource_key_to_string(key, key_str, sizeof key_str));
}
LIST_PREPEND(queries, m->dns_queries, q);
assert(q);
assert(auxiliary_for);
- /* Ensure that that the query is not auxiliary yet, and
+ /* Ensure that the query is not auxiliary yet, and
* nothing else is auxiliary to it either */
assert(!q->auxiliary_for);
assert(!q->auxiliary_queries);
q->question_utf8,
q->ifindex,
&answer);
+ if (r == -ENXIO) {
+ /* If we get ENXIO this tells us to generate NXDOMAIN unconditionally. */
+ dns_query_reset_answer(q);
+ q->answer_rcode = DNS_RCODE_NXDOMAIN;
+ q->answer_protocol = dns_synthesize_protocol(q->flags);
+ q->answer_family = dns_synthesize_family(q->flags);
+ q->answer_authenticated = true;
+ *state = DNS_TRANSACTION_RCODE_FAILURE;
+
+ return 0;
+ }
if (r <= 0)
return r;
q->manager->event,
&q->timeout_event_source,
clock_boottime_or_monotonic(),
- now(clock_boottime_or_monotonic()) + QUERY_TIMEOUT_USEC, 0,
- on_query_timeout, q);
+ now(clock_boottime_or_monotonic()) + SD_RESOLVED_QUERY_TIMEOUT_USEC,
+ 0, on_query_timeout, q);
if (r < 0)
goto fail;
q->answer = dns_answer_unref(q->answer);
q->answer_rcode = 0;
q->answer_dnssec_result = _DNSSEC_RESULT_INVALID;
+ q->answer_authenticated = false;
q->answer_errno = c->error_code;
}
switch (t->state) {
case DNS_TRANSACTION_SUCCESS: {
- /* We found a successfuly reply, merge it into the answer */
+ /* We found a successfully reply, merge it into the answer */
r = dns_answer_extend(&q->answer, t->answer);
if (r < 0)
goto fail;
continue;
default:
- /* Any kind of failure? Store the data away,
- * if there's nothing stored yet. */
-
+ /* Any kind of failure? Store the data away, if there's nothing stored yet. */
if (state == DNS_TRANSACTION_SUCCESS)
continue;
+ /* If there's already an authenticated negative reply stored, then prefer that over any unauthenticated one */
+ if (q->answer_authenticated && !t->answer_authenticated)
+ continue;
+
q->answer = dns_answer_unref(q->answer);
q->answer_rcode = t->answer_rcode;
q->answer_dnssec_result = t->answer_dnssec_result;
+ q->answer_authenticated = t->answer_authenticated;
q->answer_errno = t->answer_errno;
state = t->state;
assert(q);
- q->n_cname_redirects ++;
+ q->n_cname_redirects++;
if (q->n_cname_redirects > CNAME_MAX)
return -ELOOP;
if (r == 0 && k == 0) /* No actual cname happened? */
return -ELOOP;
+ if (q->answer_protocol == DNS_PROTOCOL_DNS) {
+ /* Don't permit CNAME redirects from unicast DNS to LLMNR or MulticastDNS, so that global resources
+ * cannot invade the local namespace. The opposite way we permit: local names may redirect to global
+ * ones. */
+
+ q->flags &= ~(SD_RESOLVED_LLMNR|SD_RESOLVED_MDNS); /* mask away the local protocols */
+ }
+
+ /* Turn off searching for the new name */
+ q->flags |= SD_RESOLVED_NO_SEARCH;
+
dns_question_unref(q->question_idna);
q->question_idna = nq_idna;
nq_idna = NULL;
dns_query_free_candidates(q);
dns_query_reset_answer(q);
- q->state = DNS_TRANSACTION_NULL;
- /* Turn off searching for the new name */
- q->flags |= SD_RESOLVED_NO_SEARCH;
+ q->state = DNS_TRANSACTION_NULL;
return 0;
}
if (q->flags & SD_RESOLVED_NO_CNAME)
return -ELOOP;
+ if (!q->answer_authenticated)
+ q->previous_redirect_unauthenticated = true;
+
/* OK, let's actually follow the CNAME */
r = dns_query_cname_redirect(q, cname);
if (r < 0)
return dns_question_first_name(q->question_idna);
}
+
+bool dns_query_fully_authenticated(DnsQuery *q) {
+ assert(q);
+
+ return q->answer_authenticated && !q->previous_redirect_unauthenticated;
+}