#include <netinet/tcp.h>
-#include "missing.h"
-#include "strv.h"
-#include "socket-util.h"
#include "af-list.h"
-#include "random-util.h"
-#include "hostname-util.h"
+#include "alloc-util.h"
#include "dns-domain.h"
-#include "resolved-llmnr.h"
+#include "fd-util.h"
+#include "hostname-util.h"
+#include "missing.h"
+#include "random-util.h"
#include "resolved-dns-scope.h"
+#include "resolved-llmnr.h"
+#include "socket-util.h"
+#include "strv.h"
#define MULTICAST_RATELIMIT_INTERVAL_USEC (1*USEC_PER_SEC)
#define MULTICAST_RATELIMIT_BURST 1000
+/* After how much time to repeat LLMNR requests, see RFC 4795 Section 7 */
+#define MULTICAST_RESEND_TIMEOUT_MIN_USEC (100 * USEC_PER_MSEC)
+#define MULTICAST_RESEND_TIMEOUT_MAX_USEC (1 * USEC_PER_SEC)
+
int dns_scope_new(Manager *m, DnsScope **ret, Link *l, DnsProtocol protocol, int family) {
DnsScope *s;
s->link = l;
s->protocol = protocol;
s->family = family;
+ s->resend_timeout = MULTICAST_RESEND_TIMEOUT_MIN_USEC;
LIST_PREPEND(scopes, m->dns_scopes, s);
dns_scope_llmnr_membership(s, false);
- while ((t = s->transactions)) {
-
+ while ((t = hashmap_steal_first(s->transactions))) {
/* Abort the transaction, but make sure it is not
* freed while we still look at it */
dns_transaction_free(t);
}
+ hashmap_free(s->transactions);
+
while ((rr = ordered_hashmap_steal_first(s->conflict_queue)))
dns_resource_record_unref(rr);
dns_zone_flush(&s->zone);
LIST_REMOVE(scopes, s->manager->dns_scopes, s);
- strv_free(s->domains);
free(s);
return NULL;
manager_next_dns_server(s->manager);
}
-int dns_scope_emit(DnsScope *s, DnsTransaction *t, DnsPacket *p, DnsServer **server) {
- DnsServer *srv = NULL;
+void dns_scope_packet_received(DnsScope *s, usec_t rtt) {
+ assert(s);
+
+ if (rtt <= s->max_rtt)
+ return;
+
+ s->max_rtt = rtt;
+ s->resend_timeout = MIN(MAX(MULTICAST_RESEND_TIMEOUT_MIN_USEC, s->max_rtt * 2), MULTICAST_RESEND_TIMEOUT_MAX_USEC);
+}
+
+void dns_scope_packet_lost(DnsScope *s, usec_t usec) {
+ assert(s);
+
+ if (s->resend_timeout <= usec)
+ s->resend_timeout = MIN(s->resend_timeout * 2, MULTICAST_RESEND_TIMEOUT_MAX_USEC);
+}
+
+int dns_scope_emit(DnsScope *s, int fd, DnsPacket *p) {
union in_addr_union addr;
int ifindex = 0, r;
int family;
uint16_t port;
uint32_t mtu;
- int fd;
assert(s);
assert(p);
assert(p->protocol == s->protocol);
+ assert((s->protocol == DNS_PROTOCOL_DNS) != (fd < 0));
if (s->link) {
mtu = s->link->mtu;
} else
mtu = manager_find_mtu(s->manager);
- if (s->protocol == DNS_PROTOCOL_DNS) {
+ switch (s->protocol) {
+ case DNS_PROTOCOL_DNS:
if (DNS_PACKET_QDCOUNT(p) > 1)
return -EOPNOTSUPP;
- srv = dns_scope_get_dns_server(s);
- if (!srv)
- return -ESRCH;
-
- family = srv->family;
- addr = srv->address;
- port = 53;
-
if (p->size > DNS_PACKET_UNICAST_SIZE_MAX)
return -EMSGSIZE;
if (p->size + UDP_PACKET_HEADER_SIZE > mtu)
return -EMSGSIZE;
- if (family == AF_INET)
- fd = transaction_dns_ipv4_fd(t);
- else if (family == AF_INET6)
- fd = transaction_dns_ipv6_fd(t);
- else
- return -EAFNOSUPPORT;
- if (fd < 0)
- return fd;
+ r = manager_write(s->manager, fd, p);
+ if (r < 0)
+ return r;
- } else if (s->protocol == DNS_PROTOCOL_LLMNR) {
+ break;
+ case DNS_PROTOCOL_LLMNR:
if (DNS_PACKET_QDCOUNT(p) > 1)
return -EOPNOTSUPP;
return -EAFNOSUPPORT;
if (fd < 0)
return fd;
- } else
- return -EAFNOSUPPORT;
- r = manager_send(s->manager, fd, ifindex, family, &addr, port, p);
- if (r < 0)
- return r;
+ r = manager_send(s->manager, fd, ifindex, family, &addr, port, p);
+ if (r < 0)
+ return r;
- if (server)
- *server = srv;
+ break;
+
+ default:
+ return -EAFNOSUPPORT;
+ }
return 1;
}
-int dns_scope_tcp_socket(DnsScope *s, int family, const union in_addr_union *address, uint16_t port, DnsServer **server) {
+static int dns_scope_socket(DnsScope *s, int type, int family, const union in_addr_union *address, uint16_t port, DnsServer **server) {
DnsServer *srv = NULL;
_cleanup_close_ int fd = -1;
union sockaddr_union sa = {};
return -EAFNOSUPPORT;
}
- fd = socket(sa.sa.sa_family, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
+ fd = socket(sa.sa.sa_family, type|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
if (fd < 0)
return -errno;
- r = setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &one, sizeof(one));
- if (r < 0)
- return -errno;
+ if (type == SOCK_STREAM) {
+ r = setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &one, sizeof(one));
+ if (r < 0)
+ return -errno;
+ }
if (s->link) {
uint32_t ifindex = htobe32(s->link->ifindex);
return ret;
}
+int dns_scope_udp_dns_socket(DnsScope *s, DnsServer **server) {
+ return dns_scope_socket(s, SOCK_DGRAM, AF_UNSPEC, NULL, 53, server);
+}
+
+int dns_scope_tcp_socket(DnsScope *s, int family, const union in_addr_union *address, uint16_t port, DnsServer **server) {
+ return dns_scope_socket(s, SOCK_STREAM, family, address, port, server);
+}
+
DnsScopeMatch dns_scope_good_domain(DnsScope *s, int ifindex, uint64_t flags, const char *domain) {
- char **i;
+ DnsSearchDomain *d;
assert(s);
assert(domain);
if ((SD_RESOLVED_FLAGS_MAKE(s->protocol, s->family) & flags) == 0)
return DNS_SCOPE_NO;
- STRV_FOREACH(i, s->domains)
- if (dns_name_endswith(domain, *i) > 0)
- return DNS_SCOPE_YES;
-
if (dns_name_root(domain) != 0)
return DNS_SCOPE_NO;
- if (is_localhost(domain))
+ /* Never resolve any loopback hostname or IP address via DNS,
+ * LLMNR or mDNS. Instead, always rely on synthesized RRs for
+ * these. */
+ if (is_localhost(domain) ||
+ dns_name_endswith(domain, "127.in-addr.arpa") > 0 ||
+ dns_name_equal(domain, "1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa") > 0)
return DNS_SCOPE_NO;
- if (s->protocol == DNS_PROTOCOL_DNS) {
+ LIST_FOREACH(domains, d, dns_scope_get_search_domains(s))
+ if (dns_name_endswith(domain, d->name) > 0)
+ return DNS_SCOPE_YES;
+
+ switch (s->protocol) {
+ case DNS_PROTOCOL_DNS:
if (dns_name_endswith(domain, "254.169.in-addr.arpa") == 0 &&
dns_name_endswith(domain, "0.8.e.f.ip6.arpa") == 0 &&
dns_name_single_label(domain) == 0)
return DNS_SCOPE_MAYBE;
return DNS_SCOPE_NO;
- }
- if (s->protocol == DNS_PROTOCOL_MDNS) {
- if (dns_name_endswith(domain, "254.169.in-addr.arpa") > 0 ||
- dns_name_endswith(domain, "0.8.e.f.ip6.arpa") > 0 ||
- (dns_name_endswith(domain, "local") > 0 && dns_name_equal(domain, "local") == 0))
+ case DNS_PROTOCOL_MDNS:
+ if ((s->family == AF_INET && dns_name_endswith(domain, "in-addr.arpa") > 0) ||
+ (s->family == AF_INET6 && dns_name_endswith(domain, "ip6.arpa") > 0) ||
+ (dns_name_endswith(domain, "local") > 0 && /* only resolve names ending in .local via mDNS */
+ dns_name_equal(domain, "local") == 0 && /* but not the single-label "local" name itself */
+ manager_is_own_hostname(s->manager, domain) <= 0)) /* never resolve the local hostname via mDNS */
return DNS_SCOPE_MAYBE;
return DNS_SCOPE_NO;
- }
- if (s->protocol == DNS_PROTOCOL_LLMNR) {
- if (dns_name_endswith(domain, "in-addr.arpa") > 0 ||
- dns_name_endswith(domain, "ip6.arpa") > 0 ||
- (dns_name_single_label(domain) > 0 &&
- dns_name_equal(domain, "gateway") <= 0)) /* don't resolve "gateway" with LLMNR, let nss-myhostname handle this */
+ case DNS_PROTOCOL_LLMNR:
+ if ((s->family == AF_INET && dns_name_endswith(domain, "in-addr.arpa") > 0) ||
+ (s->family == AF_INET6 && dns_name_endswith(domain, "ip6.arpa") > 0) ||
+ (dns_name_single_label(domain) > 0 && /* only resolve single label names via LLMNR */
+ !is_gateway_hostname(domain) && /* don't resolve "gateway" with LLMNR, let nss-myhostname handle this */
+ manager_is_own_hostname(s->manager, domain) <= 0)) /* never resolve the local hostname via LLMNR */
return DNS_SCOPE_MAYBE;
return DNS_SCOPE_NO;
- }
- assert_not_reached("Unknown scope protocol");
+ default:
+ assert_not_reached("Unknown scope protocol");
+ }
}
int dns_scope_good_key(DnsScope *s, DnsResourceKey *key) {
if (answer) {
for (i = 0; i < answer->n_rrs; i++) {
- r = dns_packet_append_rr(p, answer->rrs[i], NULL);
+ r = dns_packet_append_rr(p, answer->items[i].rr, NULL);
if (r < 0)
return r;
}
if (soa) {
for (i = 0; i < soa->n_rrs; i++) {
- r = dns_packet_append_rr(p, soa->rrs[i], NULL);
+ r = dns_packet_append_rr(p, soa->items[i].rr, NULL);
if (r < 0)
return r;
}
dns_zone_verify_conflicts(&s->zone, p->question->keys[n]);
if (p->answer)
for (n = 0; n < p->answer->n_rrs; n++)
- dns_zone_verify_conflicts(&s->zone, p->answer->rrs[n]->key);
+ dns_zone_verify_conflicts(&s->zone, p->answer->items[n].rr->key);
}
void dns_scope_process_query(DnsScope *s, DnsStream *stream, DnsPacket *p) {
_cleanup_(dns_packet_unrefp) DnsPacket *reply = NULL;
_cleanup_(dns_answer_unrefp) DnsAnswer *answer = NULL, *soa = NULL;
+ DnsResourceKey *key = NULL;
bool tentative = false;
int r, fd;
return;
}
- r = dns_zone_lookup(&s->zone, p->question, &answer, &soa, &tentative);
+ assert(p->question->n_keys == 1);
+ key = p->question->keys[0];
+
+ r = dns_zone_lookup(&s->zone, key, &answer, &soa, &tentative);
if (r < 0) {
log_debug_errno(r, "Failed to lookup key: %m");
return;
}
}
-DnsTransaction *dns_scope_find_transaction(DnsScope *scope, DnsQuestion *question, bool cache_ok) {
+DnsTransaction *dns_scope_find_transaction(DnsScope *scope, DnsResourceKey *key, bool cache_ok) {
DnsTransaction *t;
assert(scope);
- assert(question);
-
- /* Try to find an ongoing transaction that is a equal or a
- * superset of the specified question */
-
- LIST_FOREACH(transactions_by_scope, t, scope->transactions) {
+ assert(key);
- /* Refuse reusing transactions that completed based on
- * cached data instead of a real packet, if that's
- * requested. */
- if (!cache_ok &&
- IN_SET(t->state, DNS_TRANSACTION_SUCCESS, DNS_TRANSACTION_FAILURE) &&
- !t->received)
- continue;
+ /* Try to find an ongoing transaction that is a equal to the
+ * specified question */
+ t = hashmap_get(scope->transactions, key);
+ if (!t)
+ return NULL;
- if (dns_question_is_superset(t->question, question) > 0)
- return t;
- }
+ /* Refuse reusing transactions that completed based on cached
+ * data instead of a real packet, if that's requested. */
+ if (!cache_ok &&
+ IN_SET(t->state, DNS_TRANSACTION_SUCCESS, DNS_TRANSACTION_FAILURE) &&
+ !t->received)
+ return NULL;
- return NULL;
+ return t;
}
static int dns_scope_make_conflict_packet(
return 0;
}
- r = dns_scope_emit(scope, NULL, p, NULL);
+ r = dns_scope_emit(scope, -1, p);
if (r < 0)
log_debug_errno(r, "Failed to send conflict packet: %m");
}
/* Check for conflicts against the local zone. If we
* found one, we won't check any further */
- r = dns_zone_check_conflicts(&scope->zone, p->answer->rrs[i]);
+ r = dns_zone_check_conflicts(&scope->zone, p->answer->items[i].rr);
if (r != 0)
continue;
/* Check for conflicts against the local cache. If so,
* send out an advisory query, to inform everybody */
- r = dns_cache_check_conflicts(&scope->cache, p->answer->rrs[i], p->family, &p->sender);
+ r = dns_cache_check_conflicts(&scope->cache, p->answer->items[i].rr, p->family, &p->sender);
if (r <= 0)
continue;
- dns_scope_notify_conflict(scope, p->answer->rrs[i]);
+ dns_scope_notify_conflict(scope, p->answer->items[i].rr);
}
}
+
+void dns_scope_dump(DnsScope *s, FILE *f) {
+ assert(s);
+
+ if (!f)
+ f = stdout;
+
+ fputs("[Scope protocol=", f);
+ fputs(dns_protocol_to_string(s->protocol), f);
+
+ if (s->link) {
+ fputs(" interface=", f);
+ fputs(s->link->name, f);
+ }
+
+ if (s->family != AF_UNSPEC) {
+ fputs(" family=", f);
+ fputs(af_to_name(s->family), f);
+ }
+
+ fputs("]\n", f);
+
+ if (!dns_zone_is_empty(&s->zone)) {
+ fputs("ZONE:\n", f);
+ dns_zone_dump(&s->zone, f);
+ }
+
+ if (!dns_cache_is_empty(&s->cache)) {
+ fputs("CACHE:\n", f);
+ dns_cache_dump(&s->cache, f);
+ }
+}
+
+DnsSearchDomain *dns_scope_get_search_domains(DnsScope *s) {
+
+ if (s->protocol != DNS_PROTOCOL_DNS)
+ return NULL;
+
+ if (s->link)
+ return s->link->search_domains;
+
+ return NULL;
+}