--- /dev/null
+/* SPDX-License-Identifier: LGPL-2.1+ */
+
+#include "in-addr-util.h"
+#include "resolved-dns-synthesize.h"
+#include "resolved-varlink.h"
+#include "socket-netlink.h"
+
+typedef struct LookupParameters {
+ int ifindex;
+ uint64_t flags;
+ int family;
+ union in_addr_union address;
+ size_t address_size;
+ char *name;
+} LookupParameters;
+
+static void lookup_parameters_destroy(LookupParameters *p) {
+ assert(p);
+ free(p->name);
+}
+
+static int reply_query_state(DnsQuery *q) {
+
+ assert(q);
+ assert(q->varlink_request);
+
+ switch (q->state) {
+
+ case DNS_TRANSACTION_NO_SERVERS:
+ return varlink_error(q->varlink_request, "io.systemd.Resolve.NoNameServers", NULL);
+
+ case DNS_TRANSACTION_TIMEOUT:
+ return varlink_error(q->varlink_request, "io.systemd.Resolve.QueryTimedOut", NULL);
+
+ case DNS_TRANSACTION_ATTEMPTS_MAX_REACHED:
+ return varlink_error(q->varlink_request, "io.systemd.Resolve.MaxAttemptsReached", NULL);
+
+ case DNS_TRANSACTION_INVALID_REPLY:
+ return varlink_error(q->varlink_request, "io.systemd.Resolve.InvalidReply", NULL);
+
+ case DNS_TRANSACTION_ERRNO:
+ return varlink_error_errno(q->varlink_request, q->answer_errno);
+
+ case DNS_TRANSACTION_ABORTED:
+ return varlink_error(q->varlink_request, "io.systemd.Resolve.QueryAborted", NULL);
+
+ case DNS_TRANSACTION_DNSSEC_FAILED:
+ return varlink_errorb(q->varlink_request, "io.systemd.Resolve.DNSSECValidationFailed",
+ JSON_BUILD_OBJECT(JSON_BUILD_PAIR("result", JSON_BUILD_STRING(dnssec_result_to_string(q->answer_dnssec_result)))));
+
+ case DNS_TRANSACTION_NO_TRUST_ANCHOR:
+ return varlink_error(q->varlink_request, "io.systemd.Resolve.NoTrustAnchor", NULL);
+
+ case DNS_TRANSACTION_RR_TYPE_UNSUPPORTED:
+ return varlink_error(q->varlink_request, "io.systemd.Resolve.ResourceRecordTypeUnsupported", NULL);
+
+ case DNS_TRANSACTION_NETWORK_DOWN:
+ return varlink_error(q->varlink_request, "io.systemd.Resolve.NetworkDown", NULL);
+
+ case DNS_TRANSACTION_NOT_FOUND:
+ /* We return this as NXDOMAIN. This is only generated when a host doesn't implement LLMNR/TCP, and we
+ * thus quickly know that we cannot resolve an in-addr.arpa or ip6.arpa address. */
+ return varlink_errorb(q->varlink_request, "io.systemd.Resolve.DNSError",
+ JSON_BUILD_OBJECT(JSON_BUILD_PAIR("rcode", JSON_BUILD_INTEGER(DNS_RCODE_NXDOMAIN))));
+
+ case DNS_TRANSACTION_RCODE_FAILURE:
+ return varlink_errorb(q->varlink_request, "io.systemd.Resolve.DNSError",
+ JSON_BUILD_OBJECT(JSON_BUILD_PAIR("rcode", JSON_BUILD_INTEGER(q->answer_rcode))));
+
+ case DNS_TRANSACTION_NULL:
+ case DNS_TRANSACTION_PENDING:
+ case DNS_TRANSACTION_VALIDATING:
+ case DNS_TRANSACTION_SUCCESS:
+ default:
+ assert_not_reached("Impossible state");
+ }
+}
+
+static void vl_on_disconnect(VarlinkServer *s, Varlink *link, void *userdata) {
+ DnsQuery *q;
+
+ assert(s);
+ assert(link);
+
+ q = varlink_get_userdata(link);
+ if (!q)
+ return;
+
+ if (!DNS_TRANSACTION_IS_LIVE(q->state))
+ return;
+
+ log_debug("Client of active query vanished, aborting query.");
+ dns_query_complete(q, DNS_TRANSACTION_ABORTED);
+}
+
+static bool validate_and_mangle_flags(uint64_t *flags, uint64_t ok) {
+ assert(flags);
+
+ /* This checks that the specified client-provided flags parameter actually makes sense, and mangles
+ * it slightly. Specifically:
+ *
+ * 1. We check that only the protocol flags and the NO_CNAME flag are on at most, plus the
+ * method-specific flags specified in 'ok'.
+ *
+ * 2. If no protocols are enabled we automatically convert that to "all protocols are enabled".
+ *
+ * The second rule means that clients can just pass 0 as flags for the common case, and all supported
+ * protocols are enabled. Moreover it's useful so that client's do not have to be aware of all
+ * protocols implemented in resolved, but can use 0 as protocols flags set as indicator for
+ * "everything".
+ */
+
+ if (*flags & ~(SD_RESOLVED_PROTOCOLS_ALL|SD_RESOLVED_NO_CNAME|ok))
+ return false;
+
+ if ((*flags & SD_RESOLVED_PROTOCOLS_ALL) == 0) /* If no protocol is enabled, enable all */
+ *flags |= SD_RESOLVED_PROTOCOLS_ALL;
+
+ return true;
+}
+
+static void vl_method_resolve_hostname_complete(DnsQuery *q) {
+ _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *canonical = NULL;
+ _cleanup_(json_variant_unrefp) JsonVariant *array = NULL;
+ _cleanup_free_ char *normalized = NULL;
+ DnsResourceRecord *rr;
+ DnsQuestion *question;
+ int ifindex, r;
+
+ assert(q);
+
+ if (q->state != DNS_TRANSACTION_SUCCESS) {
+ r = reply_query_state(q);
+ goto finish;
+ }
+
+ r = dns_query_process_cname(q);
+ if (r == -ELOOP) {
+ r = varlink_error(q->varlink_request, "io.systemd.Resolve.CNAMELoop", NULL);
+ goto finish;
+ }
+ if (r < 0)
+ goto finish;
+ if (r == DNS_QUERY_RESTARTED) /* This was a cname, and the query was restarted. */
+ return;
+
+ question = dns_query_question_for_protocol(q, q->answer_protocol);
+
+ DNS_ANSWER_FOREACH_IFINDEX(rr, ifindex, q->answer) {
+ _cleanup_(json_variant_unrefp) JsonVariant *entry = NULL;
+ int family;
+ const void *p;
+
+ r = dns_question_matches_rr(question, rr, DNS_SEARCH_DOMAIN_NAME(q->answer_search_domain));
+ if (r < 0)
+ goto finish;
+ if (r == 0)
+ continue;
+
+ if (rr->key->type == DNS_TYPE_A) {
+ family = AF_INET;
+ p = &rr->a.in_addr;
+ } else if (rr->key->type == DNS_TYPE_AAAA) {
+ family = AF_INET6;
+ p = &rr->aaaa.in6_addr;
+ } else {
+ r = -EAFNOSUPPORT;
+ goto finish;
+ }
+
+ r = json_build(&entry,
+ JSON_BUILD_OBJECT(
+ JSON_BUILD_PAIR("ifindex", JSON_BUILD_INTEGER(ifindex)),
+ JSON_BUILD_PAIR("family", JSON_BUILD_INTEGER(family)),
+ JSON_BUILD_PAIR("address", JSON_BUILD_BYTE_ARRAY(p, FAMILY_ADDRESS_SIZE(family)))));
+ if (r < 0)
+ goto finish;
+
+ if (!canonical)
+ canonical = dns_resource_record_ref(rr);
+
+ r = json_variant_append_array(&array, entry);
+ if (r < 0)
+ goto finish;
+ }
+
+ if (json_variant_is_blank_object(array)) {
+ r = varlink_error(q->varlink_request, "io.systemd.Resolve.NoSuchResourceRecord", NULL);
+ goto finish;
+ }
+
+ assert(canonical);
+ r = dns_name_normalize(dns_resource_key_name(canonical->key), 0, &normalized);
+ if (r < 0)
+ goto finish;
+
+ r = varlink_replyb(q->varlink_request,
+ JSON_BUILD_OBJECT(
+ JSON_BUILD_PAIR("addresses", JSON_BUILD_VARIANT(array)),
+ JSON_BUILD_PAIR("name", JSON_BUILD_STRING(normalized)),
+ JSON_BUILD_PAIR("flags", JSON_BUILD_INTEGER(SD_RESOLVED_FLAGS_MAKE(q->answer_protocol, q->answer_family, dns_query_fully_authenticated(q))))));
+finish:
+ if (r < 0) {
+ log_error_errno(r, "Failed to send hostname reply: %m");
+ r = varlink_error_errno(q->varlink_request, r);
+ }
+
+ dns_query_free(q);
+}
+
+static int parse_as_address(Varlink *link, LookupParameters *p) {
+ _cleanup_free_ char *canonical = NULL;
+ int r, ff, parsed_ifindex, ifindex;
+ union in_addr_union parsed;
+
+ assert(link);
+ assert(p);
+
+ /* Check if this parses as literal address. If so, just parse it and return that, do not involve networking */
+ r = in_addr_ifindex_from_string_auto(p->name, &ff, &parsed, &parsed_ifindex);
+ if (r < 0)
+ return 0; /* not a literal address */
+
+ /* Make sure the data we parsed matches what is requested */
+ if ((p->family != AF_UNSPEC && ff != p->family) ||
+ (p->ifindex > 0 && parsed_ifindex > 0 && parsed_ifindex != p->ifindex))
+ return varlink_error(link, "io.systemd.Resolve.NoSuchResourceRecord", NULL);
+
+ ifindex = parsed_ifindex > 0 ? parsed_ifindex : p->ifindex;
+
+ /* Reformat the address as string, to return as canonicalized name */
+ r = in_addr_ifindex_to_string(ff, &parsed, ifindex, &canonical);
+ if (r < 0)
+ return r;
+
+ return varlink_replyb(
+ link,
+ JSON_BUILD_OBJECT(
+ JSON_BUILD_PAIR("addresses",
+ JSON_BUILD_ARRAY(
+ JSON_BUILD_OBJECT(
+ JSON_BUILD_PAIR_CONDITION(ifindex > 0, "ifindex", JSON_BUILD_INTEGER(ifindex)),
+ JSON_BUILD_PAIR("family", JSON_BUILD_INTEGER(ff)),
+ JSON_BUILD_PAIR("address", JSON_BUILD_BYTE_ARRAY(&parsed, FAMILY_ADDRESS_SIZE(ff)))))),
+ JSON_BUILD_PAIR("name", JSON_BUILD_STRING(canonical)),
+ JSON_BUILD_PAIR("flags", JSON_BUILD_INTEGER(SD_RESOLVED_FLAGS_MAKE(dns_synthesize_protocol(p->flags), ff, true)))));
+}
+
+static int vl_method_resolve_hostname(Varlink *link, JsonVariant *parameters, VarlinkMethodFlags flags, void *userdata) {
+ static const JsonDispatch dispatch_table[] = {
+ { "ifindex", JSON_VARIANT_UNSIGNED, json_dispatch_int, offsetof(LookupParameters, ifindex), 0 },
+ { "name", JSON_VARIANT_STRING, json_dispatch_string, offsetof(LookupParameters, name), JSON_MANDATORY },
+ { "family", JSON_VARIANT_UNSIGNED, json_dispatch_int, offsetof(LookupParameters, family), 0 },
+ { "flags", JSON_VARIANT_UNSIGNED, json_dispatch_uint64, offsetof(LookupParameters, flags), 0 },
+ {}
+ };
+
+ _cleanup_(dns_question_unrefp) DnsQuestion *question_idna = NULL, *question_utf8 = NULL;
+ _cleanup_(lookup_parameters_destroy) LookupParameters p = {
+ .family = AF_UNSPEC,
+ };
+ Manager *m = userdata;
+ DnsQuery *q;
+ int r;
+
+ assert(link);
+ assert(m);
+
+ if (FLAGS_SET(flags, VARLINK_METHOD_ONEWAY))
+ return -EINVAL;
+
+ r = json_dispatch(parameters, dispatch_table, NULL, 0, &p);
+ if (r < 0)
+ return r;
+
+ if (p.ifindex < 0)
+ return varlink_error_invalid_parameter(link, JSON_VARIANT_STRING_CONST("ifindex"));
+
+ r = dns_name_is_valid(p.name);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return varlink_error_invalid_parameter(link, JSON_VARIANT_STRING_CONST("name"));
+
+ if (!IN_SET(p.family, AF_UNSPEC, AF_INET, AF_INET6))
+ return varlink_error_invalid_parameter(link, JSON_VARIANT_STRING_CONST("family"));
+
+ if (!validate_and_mangle_flags(&p.flags, SD_RESOLVED_NO_SEARCH))
+ return varlink_error_invalid_parameter(link, JSON_VARIANT_STRING_CONST("flags"));
+
+ r = parse_as_address(link, &p);
+ if (r != 0)
+ return r;
+
+ r = dns_question_new_address(&question_utf8, p.family, p.name, false);
+ if (r < 0)
+ return r;
+
+ r = dns_question_new_address(&question_idna, p.family, p.name, true);
+ if (r < 0 && r != -EALREADY)
+ return r;
+
+ r = dns_query_new(m, &q, question_utf8, question_idna ?: question_utf8, p.ifindex, p.flags);
+ if (r < 0)
+ return r;
+
+ q->varlink_request = varlink_ref(link);
+ varlink_set_userdata(link, q);
+ q->request_family = p.family;
+ q->complete = vl_method_resolve_hostname_complete;
+
+ r = dns_query_go(q);
+ if (r < 0)
+ goto fail;
+
+ return 1;
+
+fail:
+ dns_query_free(q);
+ return r;
+}
+
+static int json_dispatch_address(const char *name, JsonVariant *variant, JsonDispatchFlags flags, void *userdata) {
+ LookupParameters *p = userdata;
+ union in_addr_union buf = {};
+ JsonVariant *i;
+ size_t n, k = 0;
+
+ assert(variant);
+ assert(p);
+
+ if (!json_variant_is_array(variant))
+ return json_log(variant, flags, SYNTHETIC_ERRNO(EINVAL), "JSON field '%s' is not an array.", strna(name));
+
+ n = json_variant_elements(variant);
+ if (!IN_SET(n, 4, 16))
+ return json_log(variant, flags, SYNTHETIC_ERRNO(EINVAL), "JSON field '%s' is array of unexpected size.", strna(name));
+
+ JSON_VARIANT_ARRAY_FOREACH(i, variant) {
+ intmax_t b;
+
+ if (!json_variant_is_integer(i))
+ return json_log(variant, flags, SYNTHETIC_ERRNO(EINVAL), "Element %zu of JSON field '%s' is not an integer.", k, strna(name));
+
+ b = json_variant_integer(i);
+ if (b < 0 || b > 0xff)
+ return json_log(variant, flags, SYNTHETIC_ERRNO(EINVAL), "Element %zu of JSON field '%s' is out of range 0…255.", k, strna(name));
+
+ buf.bytes[k++] = (uint8_t) b;
+ }
+
+ p->address = buf;
+ p->address_size = k;
+
+ return 0;
+}
+
+static void vl_method_resolve_address_complete(DnsQuery *q) {
+ _cleanup_(json_variant_unrefp) JsonVariant *array = NULL;
+ DnsQuestion *question;
+ DnsResourceRecord *rr;
+ int ifindex, r;
+
+ assert(q);
+
+ if (q->state != DNS_TRANSACTION_SUCCESS) {
+ r = reply_query_state(q);
+ goto finish;
+ }
+
+ r = dns_query_process_cname(q);
+ if (r == -ELOOP) {
+ r = varlink_error(q->varlink_request, "io.systemd.Resolve.CNAMELoop", NULL);
+ goto finish;
+ }
+ if (r < 0)
+ goto finish;
+ if (r == DNS_QUERY_RESTARTED) /* This was a cname, and the query was restarted. */
+ return;
+
+ question = dns_query_question_for_protocol(q, q->answer_protocol);
+
+ DNS_ANSWER_FOREACH_IFINDEX(rr, ifindex, q->answer) {
+ _cleanup_(json_variant_unrefp) JsonVariant *entry = NULL;
+ _cleanup_free_ char *normalized = NULL;
+
+ r = dns_question_matches_rr(question, rr, NULL);
+ if (r < 0)
+ goto finish;
+ if (r == 0)
+ continue;
+
+ r = dns_name_normalize(rr->ptr.name, 0, &normalized);
+ if (r < 0)
+ goto finish;
+
+ r = json_build(&entry,
+ JSON_BUILD_OBJECT(
+ JSON_BUILD_PAIR("ifindex", JSON_BUILD_INTEGER(ifindex)),
+ JSON_BUILD_PAIR("name", JSON_BUILD_STRING(normalized))));
+ if (r < 0)
+ goto finish;
+
+ r = json_variant_append_array(&array, entry);
+ if (r < 0)
+ goto finish;
+ }
+
+ if (json_variant_is_blank_object(array)) {
+ r = varlink_error(q->varlink_request, "io.systemd.Resolve.NoSuchResourceRecord", NULL);
+ goto finish;
+ }
+
+ r = varlink_replyb(q->varlink_request,
+ JSON_BUILD_OBJECT(
+ JSON_BUILD_PAIR("names", JSON_BUILD_VARIANT(array)),
+ JSON_BUILD_PAIR("flags", JSON_BUILD_INTEGER(SD_RESOLVED_FLAGS_MAKE(q->answer_protocol, q->answer_family, dns_query_fully_authenticated(q))))));
+finish:
+ if (r < 0) {
+ log_error_errno(r, "Failed to send address reply: %m");
+ r = varlink_error_errno(q->varlink_request, r);
+ }
+
+ dns_query_free(q);
+}
+
+static int vl_method_resolve_address(Varlink *link, JsonVariant *parameters, VarlinkMethodFlags flags, void *userdata) {
+ static const JsonDispatch dispatch_table[] = {
+ { "ifindex", JSON_VARIANT_UNSIGNED, json_dispatch_int, offsetof(LookupParameters, ifindex), 0 },
+ { "family", JSON_VARIANT_UNSIGNED, json_dispatch_int, offsetof(LookupParameters, family), JSON_MANDATORY },
+ { "address", JSON_VARIANT_ARRAY, json_dispatch_address, 0, JSON_MANDATORY },
+ { "flags", JSON_VARIANT_UNSIGNED, json_dispatch_uint64, offsetof(LookupParameters, flags), 0 },
+ {}
+ };
+
+ _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+ _cleanup_(lookup_parameters_destroy) LookupParameters p = {
+ .family = AF_UNSPEC,
+ };
+ Manager *m = userdata;
+ DnsQuery *q;
+ int r;
+
+ assert(link);
+ assert(m);
+
+ if (FLAGS_SET(flags, VARLINK_METHOD_ONEWAY))
+ return -EINVAL;
+
+ r = json_dispatch(parameters, dispatch_table, NULL, 0, &p);
+ if (r < 0)
+ return r;
+
+ if (p.ifindex < 0)
+ return varlink_error_invalid_parameter(link, JSON_VARIANT_STRING_CONST("ifindex"));
+
+ if (!IN_SET(p.family, AF_UNSPEC, AF_INET, AF_INET6))
+ return varlink_error_invalid_parameter(link, JSON_VARIANT_STRING_CONST("family"));
+
+ if (FAMILY_ADDRESS_SIZE(p.family) != p.address_size)
+ return varlink_error(link, "io.systemd.UserDatabase.BadAddressSize", NULL);
+
+ if (!validate_and_mangle_flags(&p.flags, 0))
+ return varlink_error_invalid_parameter(link, JSON_VARIANT_STRING_CONST("flags"));
+
+ r = dns_question_new_reverse(&question, p.family, &p.address);
+ if (r < 0)
+ return r;
+
+ r = dns_query_new(m, &q, question, question, p.ifindex, p.flags|SD_RESOLVED_NO_SEARCH);
+ if (r < 0)
+ return r;
+
+ q->varlink_request = varlink_ref(link);
+ varlink_set_userdata(link, q);
+
+ q->request_family = p.family;
+ q->request_address = p.address;
+ q->complete = vl_method_resolve_address_complete;
+
+ r = dns_query_go(q);
+ if (r < 0)
+ goto fail;
+
+ return 1;
+
+fail:
+ dns_query_free(q);
+ return r;
+}
+
+int manager_varlink_init(Manager *m) {
+ _cleanup_(varlink_server_unrefp) VarlinkServer *s = NULL;
+ int r;
+
+ assert(m);
+
+ if (m->varlink_server)
+ return 0;
+
+ r = varlink_server_new(&s, VARLINK_SERVER_ACCOUNT_UID);
+ if (r < 0)
+ return log_error_errno(r, "Failed to allocate varlink server object: %m");
+
+ varlink_server_set_userdata(s, m);
+
+ r = varlink_server_bind_method_many(
+ s,
+ "io.systemd.Resolve.ResolveHostname", vl_method_resolve_hostname,
+ "io.systemd.Resolve.ResolveAddress", vl_method_resolve_address);
+ if (r < 0)
+ return log_error_errno(r, "Failed to register varlink methods: %m");
+
+ r = varlink_server_bind_disconnect(s, vl_on_disconnect);
+ if (r < 0)
+ return log_error_errno(r, "Failed to register varlink disconnect handler: %m");
+
+ r = varlink_server_listen_address(s, "/run/systemd/resolve/io.systemd.Resolve", 0666);
+ if (r < 0)
+ return log_error_errno(r, "Failed to bind to varlink socket: %m");
+
+ r = varlink_server_attach_event(s, m->event, SD_EVENT_PRIORITY_NORMAL);
+ if (r < 0)
+ return log_error_errno(r, "Failed to attach varlink connection to event loop: %m");
+
+ m->varlink_server = TAKE_PTR(s);
+ return 0;
+}
+
+void manager_varlink_done(Manager *m) {
+ assert(m);
+
+ m->varlink_server = varlink_server_unref(m->varlink_server);
+}
projects / thirdparty / systemd.git / commitdiff
