diff options
Diffstat (limited to 'src/resolve/resolved-dns-stub.c')
| -rw-r--r-- | src/resolve/resolved-dns-stub.c | 776 |
1 files changed, 776 insertions, 0 deletions
diff --git a/src/resolve/resolved-dns-stub.c b/src/resolve/resolved-dns-stub.c new file mode 100644 index 0000000..6a3dc99 --- /dev/null +++ b/src/resolve/resolved-dns-stub.c @@ -0,0 +1,776 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ + +#include <net/if_arp.h> + +#include "errno-util.h" +#include "fd-util.h" +#include "missing_network.h" +#include "missing_socket.h" +#include "resolved-dns-stub.h" +#include "socket-netlink.h" +#include "socket-util.h" +#include "string-table.h" + +/* The MTU of the loopback device is 64K on Linux, advertise that as maximum datagram size, but subtract the Ethernet, + * IP and UDP header sizes */ +#define ADVERTISE_DATAGRAM_SIZE_MAX (65536U-14U-20U-8U) + +/* On the extra stubs, use a more conservative choice */ +#define ADVERTISE_EXTRA_DATAGRAM_SIZE_MAX DNS_PACKET_UNICAST_SIZE_LARGE_MAX + +static int manager_dns_stub_fd_extra(Manager *m, DnsStubListenerExtra *l, int type); + +static void dns_stub_listener_extra_hash_func(const DnsStubListenerExtra *a, struct siphash *state) { + assert(a); + + siphash24_compress(&a->mode, sizeof(a->mode), state); + siphash24_compress(&a->family, sizeof(a->family), state); + siphash24_compress(&a->address, FAMILY_ADDRESS_SIZE(a->family), state); + siphash24_compress(&a->port, sizeof(a->port), state); +} + +static int dns_stub_listener_extra_compare_func(const DnsStubListenerExtra *a, const DnsStubListenerExtra *b) { + int r; + + assert(a); + assert(b); + + r = CMP(a->mode, b->mode); + if (r != 0) + return r; + + r = CMP(a->family, b->family); + if (r != 0) + return r; + + r = memcmp(&a->address, &b->address, FAMILY_ADDRESS_SIZE(a->family)); + if (r != 0) + return r; + + return CMP(a->port, b->port); +} + +DEFINE_HASH_OPS_WITH_KEY_DESTRUCTOR( + dns_stub_listener_extra_hash_ops, + DnsStubListenerExtra, + dns_stub_listener_extra_hash_func, + dns_stub_listener_extra_compare_func, + dns_stub_listener_extra_free); + +int dns_stub_listener_extra_new( + Manager *m, + DnsStubListenerExtra **ret) { + + DnsStubListenerExtra *l; + + l = new(DnsStubListenerExtra, 1); + if (!l) + return -ENOMEM; + + *l = (DnsStubListenerExtra) { + .manager = m, + }; + + *ret = TAKE_PTR(l); + return 0; +} + +DnsStubListenerExtra *dns_stub_listener_extra_free(DnsStubListenerExtra *p) { + if (!p) + return NULL; + + p->udp_event_source = sd_event_source_unref(p->udp_event_source); + p->tcp_event_source = sd_event_source_unref(p->tcp_event_source); + + return mfree(p); +} + +static int dns_stub_make_reply_packet( + DnsPacket **p, + size_t max_size, + DnsQuestion *q, + DnsAnswer *answer, + bool *ret_truncated) { + + bool truncated = false; + DnsResourceRecord *rr; + unsigned c = 0; + int r; + + assert(p); + + /* Note that we don't bother with any additional RRs, as this is stub is for local lookups only, and hence + * roundtrips aren't expensive. */ + + if (!*p) { + r = dns_packet_new(p, DNS_PROTOCOL_DNS, 0, max_size); + if (r < 0) + return r; + + r = dns_packet_append_question(*p, q); + if (r < 0) + return r; + + DNS_PACKET_HEADER(*p)->qdcount = htobe16(dns_question_size(q)); + } + + DNS_ANSWER_FOREACH(rr, answer) { + + r = dns_question_matches_rr(q, rr, NULL); + if (r < 0) + return r; + if (r > 0) + goto add; + + r = dns_question_matches_cname_or_dname(q, rr, NULL); + if (r < 0) + return r; + if (r > 0) + goto add; + + continue; + add: + r = dns_packet_append_rr(*p, rr, 0, NULL, NULL); + if (r == -EMSGSIZE) { + truncated = true; + break; + } + if (r < 0) + return r; + + c++; + } + + if (ret_truncated) + *ret_truncated = truncated; + else if (truncated) + return -EMSGSIZE; + + DNS_PACKET_HEADER(*p)->ancount = htobe16(be16toh(DNS_PACKET_HEADER(*p)->ancount) + c); + + return 0; +} + +static int dns_stub_finish_reply_packet( + DnsPacket *p, + uint16_t id, + int rcode, + bool tc, /* set the Truncated bit? */ + bool add_opt, /* add an OPT RR to this packet? */ + bool edns0_do, /* set the EDNS0 DNSSEC OK bit? */ + bool ad, /* set the DNSSEC authenticated data bit? */ + uint16_t max_udp_size) { /* The maximum UDP datagram size to advertise to clients */ + + int r; + + assert(p); + + if (add_opt) { + r = dns_packet_append_opt(p, max_udp_size, edns0_do, /* include_rfc6975 = */ false, rcode, NULL); + if (r == -EMSGSIZE) /* Hit the size limit? then indicate truncation */ + tc = true; + else if (r < 0) + return r; + + } else { + /* If the client can't to EDNS0, don't do DO either */ + edns0_do = false; + + /* If the client didn't do EDNS, clamp the rcode to 4 bit */ + if (rcode > 0xF) + rcode = DNS_RCODE_SERVFAIL; + } + + /* Don't set the AD bit unless DO is on, too */ + if (!edns0_do) + ad = false; + + DNS_PACKET_HEADER(p)->id = id; + + DNS_PACKET_HEADER(p)->flags = htobe16(DNS_PACKET_MAKE_FLAGS( + 1 /* qr */, + 0 /* opcode */, + 0 /* aa */, + tc /* tc */, + 1 /* rd */, + 1 /* ra */, + ad /* ad */, + 0 /* cd */, + rcode)); + + return 0; +} + +static int dns_stub_send( + Manager *m, + DnsStubListenerExtra *l, + DnsStream *s, + DnsPacket *p, + DnsPacket *reply) { + + int r; + + assert(m); + assert(p); + assert(reply); + + if (s) + r = dns_stream_write_packet(s, reply); + else + /* Note that it is essential here that we explicitly choose the source IP address for this packet. This + * is because otherwise the kernel will choose it automatically based on the routing table and will + * thus pick 127.0.0.1 rather than 127.0.0.53. */ + r = manager_send(m, + manager_dns_stub_fd_extra(m, l, SOCK_DGRAM), + l ? p->ifindex : LOOPBACK_IFINDEX, /* force loopback iface if this is the main listener stub */ + p->family, &p->sender, p->sender_port, &p->destination, + reply); + if (r < 0) + return log_debug_errno(r, "Failed to send reply packet: %m"); + + return 0; +} + +static int dns_stub_send_failure( + Manager *m, + DnsStubListenerExtra *l, + DnsStream *s, + DnsPacket *p, + int rcode, + bool authenticated) { + + _cleanup_(dns_packet_unrefp) DnsPacket *reply = NULL; + int r; + + assert(m); + assert(p); + + r = dns_stub_make_reply_packet(&reply, DNS_PACKET_PAYLOAD_SIZE_MAX(p), p->question, NULL, NULL); + if (r < 0) + return log_debug_errno(r, "Failed to make failure packet: %m"); + + r = dns_stub_finish_reply_packet( + reply, + DNS_PACKET_ID(p), + rcode, + /* truncated = */ false, + !!p->opt, + DNS_PACKET_DO(p), + authenticated, + l ? ADVERTISE_EXTRA_DATAGRAM_SIZE_MAX : ADVERTISE_DATAGRAM_SIZE_MAX); + if (r < 0) + return log_debug_errno(r, "Failed to build failure packet: %m"); + + return dns_stub_send(m, l, s, p, reply); +} + +static void dns_stub_query_complete(DnsQuery *q) { + int r; + + assert(q); + assert(q->request_dns_packet); + + switch (q->state) { + + case DNS_TRANSACTION_SUCCESS: { + bool truncated; + + r = dns_stub_make_reply_packet(&q->reply_dns_packet, DNS_PACKET_PAYLOAD_SIZE_MAX(q->request_dns_packet), q->question_idna, q->answer, &truncated); + if (r < 0) { + log_debug_errno(r, "Failed to build reply packet: %m"); + break; + } + + if (!truncated) { + r = dns_query_process_cname(q); + if (r == -ELOOP) { + (void) dns_stub_send_failure(q->manager, q->stub_listener_extra, q->request_dns_stream, q->request_dns_packet, DNS_RCODE_SERVFAIL, false); + break; + } + if (r < 0) { + log_debug_errno(r, "Failed to process CNAME: %m"); + break; + } + if (r == DNS_QUERY_RESTARTED) + return; + } + + r = dns_stub_finish_reply_packet( + q->reply_dns_packet, + DNS_PACKET_ID(q->request_dns_packet), + q->answer_rcode, + truncated, + !!q->request_dns_packet->opt, + DNS_PACKET_DO(q->request_dns_packet), + dns_query_fully_authenticated(q), + q->stub_listener_extra ? ADVERTISE_EXTRA_DATAGRAM_SIZE_MAX : ADVERTISE_DATAGRAM_SIZE_MAX); + if (r < 0) { + log_debug_errno(r, "Failed to finish reply packet: %m"); + break; + } + + (void) dns_stub_send(q->manager, q->stub_listener_extra, q->request_dns_stream, q->request_dns_packet, q->reply_dns_packet); + break; + } + + case DNS_TRANSACTION_RCODE_FAILURE: + (void) dns_stub_send_failure(q->manager, q->stub_listener_extra, q->request_dns_stream, q->request_dns_packet, q->answer_rcode, dns_query_fully_authenticated(q)); + break; + + case DNS_TRANSACTION_NOT_FOUND: + (void) dns_stub_send_failure(q->manager, q->stub_listener_extra, q->request_dns_stream, q->request_dns_packet, DNS_RCODE_NXDOMAIN, dns_query_fully_authenticated(q)); + break; + + case DNS_TRANSACTION_TIMEOUT: + case DNS_TRANSACTION_ATTEMPTS_MAX_REACHED: + /* Propagate a timeout as a no packet, i.e. that the client also gets a timeout */ + break; + + case DNS_TRANSACTION_NO_SERVERS: + case DNS_TRANSACTION_INVALID_REPLY: + case DNS_TRANSACTION_ERRNO: + case DNS_TRANSACTION_ABORTED: + case DNS_TRANSACTION_DNSSEC_FAILED: + case DNS_TRANSACTION_NO_TRUST_ANCHOR: + case DNS_TRANSACTION_RR_TYPE_UNSUPPORTED: + case DNS_TRANSACTION_NETWORK_DOWN: + (void) dns_stub_send_failure(q->manager, q->stub_listener_extra, q->request_dns_stream, q->request_dns_packet, DNS_RCODE_SERVFAIL, false); + break; + + case DNS_TRANSACTION_NULL: + case DNS_TRANSACTION_PENDING: + case DNS_TRANSACTION_VALIDATING: + default: + assert_not_reached("Impossible state"); + } + + dns_query_free(q); +} + +static int dns_stub_stream_complete(DnsStream *s, int error) { + assert(s); + + log_debug_errno(error, "DNS TCP connection terminated, destroying queries: %m"); + + for (;;) { + DnsQuery *q; + + q = set_first(s->queries); + if (!q) + break; + + dns_query_free(q); + } + + /* This drops the implicit ref we keep around since it was allocated, as incoming stub connections + * should be kept as long as the client wants to. */ + dns_stream_unref(s); + return 0; +} + +static void dns_stub_process_query(Manager *m, DnsStubListenerExtra *l, DnsStream *s, DnsPacket *p) { + _cleanup_(dns_query_freep) DnsQuery *q = NULL; + int r; + + assert(m); + assert(p); + assert(p->protocol == DNS_PROTOCOL_DNS); + + if (!l && /* l == NULL if this is the main stub */ + (in_addr_is_localhost(p->family, &p->sender) <= 0 || + in_addr_is_localhost(p->family, &p->destination) <= 0)) { + log_warning("Got packet on unexpected (i.e. non-localhost) IP range, ignoring."); + return; + } + + r = dns_packet_extract(p); + if (r < 0) { + log_debug_errno(r, "Failed to extract resources from incoming packet, ignoring packet: %m"); + dns_stub_send_failure(m, l, s, p, DNS_RCODE_FORMERR, false); + return; + } + + if (!DNS_PACKET_VERSION_SUPPORTED(p)) { + log_debug("Got EDNS OPT field with unsupported version number."); + dns_stub_send_failure(m, l, s, p, DNS_RCODE_BADVERS, false); + return; + } + + if (dns_type_is_obsolete(p->question->keys[0]->type)) { + log_debug("Got message with obsolete key type, refusing."); + dns_stub_send_failure(m, l, s, p, DNS_RCODE_NOTIMP, false); + return; + } + + if (dns_type_is_zone_transer(p->question->keys[0]->type)) { + log_debug("Got request for zone transfer, refusing."); + dns_stub_send_failure(m, l, s, p, DNS_RCODE_NOTIMP, false); + return; + } + + if (!DNS_PACKET_RD(p)) { + /* If the "rd" bit is off (i.e. recursion was not requested), then refuse operation */ + log_debug("Got request with recursion disabled, refusing."); + dns_stub_send_failure(m, l, s, p, DNS_RCODE_REFUSED, false); + return; + } + + if (DNS_PACKET_DO(p) && DNS_PACKET_CD(p)) { + log_debug("Got request with DNSSEC CD bit set, refusing."); + dns_stub_send_failure(m, l, s, p, DNS_RCODE_NOTIMP, false); + return; + } + + r = dns_query_new(m, &q, p->question, p->question, 0, SD_RESOLVED_PROTOCOLS_ALL|SD_RESOLVED_NO_SEARCH); + if (r < 0) { + log_error_errno(r, "Failed to generate query object: %m"); + dns_stub_send_failure(m, l, s, p, DNS_RCODE_SERVFAIL, false); + return; + } + + /* Request that the TTL is corrected by the cached time for this lookup, so that we return vaguely useful TTLs */ + q->clamp_ttl = true; + + q->request_dns_packet = dns_packet_ref(p); + q->request_dns_stream = dns_stream_ref(s); /* make sure the stream stays around until we can send a reply through it */ + q->stub_listener_extra = l; + q->complete = dns_stub_query_complete; + + if (s) { + /* Remember which queries belong to this stream, so that we can cancel them when the stream + * is disconnected early */ + + r = set_ensure_put(&s->queries, NULL, q); + if (r < 0) { + log_oom(); + return; + } + assert(r > 0); + } + + r = dns_query_go(q); + if (r < 0) { + log_error_errno(r, "Failed to start query: %m"); + dns_stub_send_failure(m, l, s, p, DNS_RCODE_SERVFAIL, false); + return; + } + + log_debug("Processing query..."); + TAKE_PTR(q); +} + +static int on_dns_stub_packet_internal(sd_event_source *s, int fd, uint32_t revents, Manager *m, DnsStubListenerExtra *l) { + _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL; + int r; + + r = manager_recv(m, fd, DNS_PROTOCOL_DNS, &p); + if (r <= 0) + return r; + + if (dns_packet_validate_query(p) > 0) { + log_debug("Got DNS stub UDP query packet for id %u", DNS_PACKET_ID(p)); + + dns_stub_process_query(m, l, NULL, p); + } else + log_debug("Invalid DNS stub UDP packet, ignoring."); + + return 0; +} + +static int on_dns_stub_packet(sd_event_source *s, int fd, uint32_t revents, void *userdata) { + return on_dns_stub_packet_internal(s, fd, revents, userdata, NULL); +} + +static int on_dns_stub_packet_extra(sd_event_source *s, int fd, uint32_t revents, void *userdata) { + DnsStubListenerExtra *l = userdata; + + assert(l); + + return on_dns_stub_packet_internal(s, fd, revents, l->manager, l); +} + +static int on_dns_stub_stream_packet(DnsStream *s) { + _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL; + + assert(s); + + p = dns_stream_take_read_packet(s); + assert(p); + + if (dns_packet_validate_query(p) > 0) { + log_debug("Got DNS stub TCP query packet for id %u", DNS_PACKET_ID(p)); + + dns_stub_process_query(s->manager, s->stub_listener_extra, s, p); + } else + log_debug("Invalid DNS stub TCP packet, ignoring."); + + return 0; +} + +static int on_dns_stub_stream_internal(sd_event_source *s, int fd, uint32_t revents, Manager *m, DnsStubListenerExtra *l) { + DnsStream *stream; + int cfd, r; + + cfd = accept4(fd, NULL, NULL, SOCK_NONBLOCK|SOCK_CLOEXEC); + if (cfd < 0) { + if (ERRNO_IS_ACCEPT_AGAIN(errno)) + return 0; + + return -errno; + } + + r = dns_stream_new(m, &stream, DNS_STREAM_STUB, DNS_PROTOCOL_DNS, cfd, NULL); + if (r < 0) { + safe_close(cfd); + return r; + } + + stream->stub_listener_extra = l; + stream->on_packet = on_dns_stub_stream_packet; + stream->complete = dns_stub_stream_complete; + + /* We let the reference to the stream dangle here, it will be dropped later by the complete callback. */ + + return 0; +} + +static int on_dns_stub_stream(sd_event_source *s, int fd, uint32_t revents, void *userdata) { + return on_dns_stub_stream_internal(s, fd, revents, userdata, NULL); +} + +static int on_dns_stub_stream_extra(sd_event_source *s, int fd, uint32_t revents, void *userdata) { + DnsStubListenerExtra *l = userdata; + + assert(l); + return on_dns_stub_stream_internal(s, fd, revents, l->manager, l); +} + +static int set_dns_stub_common_socket_options(int fd, int family) { + int r; + + assert(fd >= 0); + assert(IN_SET(family, AF_INET, AF_INET6)); + + r = setsockopt_int(fd, SOL_SOCKET, SO_REUSEADDR, true); + if (r < 0) + return r; + + r = socket_set_recvpktinfo(fd, family, true); + if (r < 0) + return r; + + r = socket_set_recvttl(fd, family, true); + if (r < 0) + return r; + + return 0; +} + +static int manager_dns_stub_fd(Manager *m, int type) { + union sockaddr_union sa = { + .in.sin_family = AF_INET, + .in.sin_addr.s_addr = htobe32(INADDR_DNS_STUB), + .in.sin_port = htobe16(53), + }; + _cleanup_close_ int fd = -1; + int r; + + assert(IN_SET(type, SOCK_DGRAM, SOCK_STREAM)); + + sd_event_source **event_source = type == SOCK_DGRAM ? &m->dns_stub_udp_event_source : &m->dns_stub_tcp_event_source; + if (*event_source) + return sd_event_source_get_io_fd(*event_source); + + fd = socket(AF_INET, type | SOCK_CLOEXEC | SOCK_NONBLOCK, 0); + if (fd < 0) + return -errno; + + r = set_dns_stub_common_socket_options(fd, AF_INET); + if (r < 0) + return r; + + /* Make sure no traffic from outside the local host can leak to onto this socket */ + r = socket_bind_to_ifindex(fd, LOOPBACK_IFINDEX); + if (r < 0) + return r; + + r = setsockopt_int(fd, IPPROTO_IP, IP_TTL, 1); + if (r < 0) + return r; + + if (bind(fd, &sa.sa, sizeof(sa.in)) < 0) + return -errno; + + if (type == SOCK_STREAM && + listen(fd, SOMAXCONN) < 0) + return -errno; + + r = sd_event_add_io(m->event, event_source, fd, EPOLLIN, + type == SOCK_DGRAM ? on_dns_stub_packet : on_dns_stub_stream, + m); + if (r < 0) + return r; + + r = sd_event_source_set_io_fd_own(*event_source, true); + if (r < 0) + return r; + + (void) sd_event_source_set_description(*event_source, + type == SOCK_DGRAM ? "dns-stub-udp" : "dns-stub-tcp"); + + return TAKE_FD(fd); +} + +static int manager_dns_stub_fd_extra(Manager *m, DnsStubListenerExtra *l, int type) { + _cleanup_free_ char *pretty = NULL; + _cleanup_close_ int fd = -1; + union sockaddr_union sa; + int r; + + assert(m); + assert(IN_SET(type, SOCK_DGRAM, SOCK_STREAM)); + + if (!l) + return manager_dns_stub_fd(m, type); + + sd_event_source **event_source = type == SOCK_DGRAM ? &l->udp_event_source : &l->tcp_event_source; + if (*event_source) + return sd_event_source_get_io_fd(*event_source); + + if (l->family == AF_INET) + sa = (union sockaddr_union) { + .in.sin_family = l->family, + .in.sin_port = htobe16(l->port != 0 ? l->port : 53U), + .in.sin_addr = l->address.in, + }; + else + sa = (union sockaddr_union) { + .in6.sin6_family = l->family, + .in6.sin6_port = htobe16(l->port != 0 ? l->port : 53U), + .in6.sin6_addr = l->address.in6, + }; + + fd = socket(l->family, type | SOCK_CLOEXEC | SOCK_NONBLOCK, 0); + if (fd < 0) { + r = -errno; + goto fail; + } + + r = set_dns_stub_common_socket_options(fd, l->family); + if (r < 0) + goto fail; + + /* Do not set IP_TTL for extra DNS stub listeners, as the address may not be local and in that case + * people may want ttl > 1. */ + + r = socket_set_freebind(fd, l->family, true); + if (r < 0) + goto fail; + + if (bind(fd, &sa.sa, SOCKADDR_LEN(sa)) < 0) { + r = -errno; + goto fail; + } + + if (type == SOCK_STREAM && + listen(fd, SOMAXCONN) < 0) { + r = -errno; + goto fail; + } + + r = sd_event_add_io(m->event, event_source, fd, EPOLLIN, + type == SOCK_DGRAM ? on_dns_stub_packet_extra : on_dns_stub_stream_extra, + l); + if (r < 0) + goto fail; + + r = sd_event_source_set_io_fd_own(*event_source, true); + if (r < 0) + goto fail; + + (void) sd_event_source_set_description(*event_source, + type == SOCK_DGRAM ? "dns-stub-udp-extra" : "dns-stub-tcp-extra"); + + if (DEBUG_LOGGING) { + (void) in_addr_port_to_string(l->family, &l->address, l->port, &pretty); + log_debug("Listening on %s socket %s.", + type == SOCK_DGRAM ? "UDP" : "TCP", + strnull(pretty)); + } + + return TAKE_FD(fd); + +fail: + assert(r < 0); + (void) in_addr_port_to_string(l->family, &l->address, l->port, &pretty); + return log_warning_errno(r, + r == -EADDRINUSE ? "Another process is already listening on %s socket %s: %m" : + "Failed to listen on %s socket %s: %m", + type == SOCK_DGRAM ? "UDP" : "TCP", + strnull(pretty)); +} + +int manager_dns_stub_start(Manager *m) { + const char *t = "UDP"; + int r = 0; + + assert(m); + + if (m->dns_stub_listener_mode == DNS_STUB_LISTENER_NO) + log_debug("Not creating stub listener."); + else + log_debug("Creating stub listener using %s.", + m->dns_stub_listener_mode == DNS_STUB_LISTENER_UDP ? "UDP" : + m->dns_stub_listener_mode == DNS_STUB_LISTENER_TCP ? "TCP" : + "UDP/TCP"); + + if (FLAGS_SET(m->dns_stub_listener_mode, DNS_STUB_LISTENER_UDP)) + r = manager_dns_stub_fd(m, SOCK_DGRAM); + + if (r >= 0 && + FLAGS_SET(m->dns_stub_listener_mode, DNS_STUB_LISTENER_TCP)) { + t = "TCP"; + r = manager_dns_stub_fd(m, SOCK_STREAM); + } + + if (IN_SET(r, -EADDRINUSE, -EPERM)) { + log_warning_errno(r, + r == -EADDRINUSE ? "Another process is already listening on %s socket 127.0.0.53:53.\n" + "Turning off local DNS stub support." : + "Failed to listen on %s socket 127.0.0.53:53: %m.\n" + "Turning off local DNS stub support.", + t); + manager_dns_stub_stop(m); + } else if (r < 0) + return log_error_errno(r, "Failed to listen on %s socket 127.0.0.53:53: %m", t); + + if (!ordered_set_isempty(m->dns_extra_stub_listeners)) { + DnsStubListenerExtra *l; + + log_debug("Creating extra stub listeners."); + + ORDERED_SET_FOREACH(l, m->dns_extra_stub_listeners) { + if (FLAGS_SET(l->mode, DNS_STUB_LISTENER_UDP)) + (void) manager_dns_stub_fd_extra(m, l, SOCK_DGRAM); + if (FLAGS_SET(l->mode, DNS_STUB_LISTENER_TCP)) + (void) manager_dns_stub_fd_extra(m, l, SOCK_STREAM); + } + } + + return 0; +} + +void manager_dns_stub_stop(Manager *m) { + assert(m); + + m->dns_stub_udp_event_source = sd_event_source_unref(m->dns_stub_udp_event_source); + m->dns_stub_tcp_event_source = sd_event_source_unref(m->dns_stub_tcp_event_source); +} + +static const char* const dns_stub_listener_mode_table[_DNS_STUB_LISTENER_MODE_MAX] = { + [DNS_STUB_LISTENER_NO] = "no", + [DNS_STUB_LISTENER_UDP] = "udp", + [DNS_STUB_LISTENER_TCP] = "tcp", + [DNS_STUB_LISTENER_YES] = "yes", +}; +DEFINE_STRING_TABLE_LOOKUP_WITH_BOOLEAN(dns_stub_listener_mode, DnsStubListenerMode, DNS_STUB_LISTENER_YES); |