diff --git a/src/resolve/meson.build b/src/resolve/meson.build
index 20caecee0f..4fc2bc8006 100644
--- a/src/resolve/meson.build
+++ b/src/resolve/meson.build
@@ -174,6 +174,9 @@ executables += [
         resolve_test_template + {
                 'sources' : files('test-dns-rr.c'),
         },
+        resolve_test_template + {
+                'sources' : files('test-dns-question.c'),
+        },
         resolve_test_template + {
                 'sources' : files(
                         'test-resolved-etc-hosts.c',
diff --git a/src/resolve/test-dns-question.c b/src/resolve/test-dns-question.c
new file mode 100644
index 0000000000..a621aeeca2
--- /dev/null
+++ b/src/resolve/test-dns-question.c
@@ -0,0 +1,1028 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include "dns-type.h"
+#include "resolved-dns-question.h"
+#include "resolved-dns-rr.h"
+
+#include "log.h"
+#include "tests.h"
+
+#include "fd-util.h"
+#include "fileio.h"
+#include "fs-util.h"
+#include "tmpfile-util.h"
+
+/* ================================================================
+ * dns_question_add()
+ * ================================================================ */
+
+TEST(dns_question_add_full) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+        _cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL;
+
+        question = dns_question_new(0);
+        ASSERT_NOT_NULL(question);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(key);
+
+        ASSERT_ERROR(dns_question_add(question, key, 0), ENOSPC);
+
+        ASSERT_FALSE(dns_question_contains_key(question, key));
+
+        assert(dns_question_size(question) == 0);
+        assert(dns_question_isempty(question) == 1);
+}
+
+TEST(dns_question_add_with_space) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+        _cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL;
+
+        assert(dns_question_size(question) == 0);
+        assert(dns_question_isempty(question) == 1);
+
+        question = dns_question_new(1);
+        ASSERT_NOT_NULL(question);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(key);
+
+        ASSERT_OK(dns_question_add(question, key, 0));
+
+        ASSERT_TRUE(dns_question_contains_key(question, key));
+
+        assert(dns_question_size(question) == 1);
+        assert(dns_question_isempty(question) == 0);
+}
+
+/* ================================================================
+ * dns_question_new_address()
+ * ================================================================ */
+
+TEST(dns_question_new_address_ipv4) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+        _cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL;
+
+        ASSERT_OK(dns_question_new_address(&question, AF_INET, "www.example.com", 0));
+        ASSERT_NOT_NULL(question);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(key);
+
+        ASSERT_EQ(dns_question_size(question), 1u);
+        ASSERT_TRUE(dns_question_contains_key(question, key));
+}
+
+TEST(dns_question_new_address_ipv6) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+        _cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL;
+
+        ASSERT_OK(dns_question_new_address(&question, AF_INET6, "www.example.com", 0));
+        ASSERT_NOT_NULL(question);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_AAAA, "www.example.com");
+        ASSERT_NOT_NULL(key);
+
+        ASSERT_EQ(dns_question_size(question), 1u);
+        ASSERT_TRUE(dns_question_contains_key(question, key));
+}
+
+#if HAVE_LIBIDN || HAVE_LIBIDN2
+TEST(dns_question_new_address_convert_idna) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+        _cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL;
+
+        ASSERT_OK(dns_question_new_address(&question, AF_INET, "www.\xF0\x9F\x98\xB1.com", 1));
+        ASSERT_NOT_NULL(question);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.xn--s38h.com");
+        ASSERT_NOT_NULL(key);
+
+        ASSERT_EQ(dns_question_size(question), 1u);
+        ASSERT_TRUE(dns_question_contains_key(question, key));
+}
+#endif
+
+/* ================================================================
+ * dns_question_new_reverse()
+ * ================================================================ */
+
+TEST(dns_question_new_reverse_ipv4) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+        _cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL;
+
+        union in_addr_union addr = { .in.s_addr = htobe32(0xc0a8017f) };
+
+        ASSERT_OK(dns_question_new_reverse(&question, AF_INET, &addr));
+        ASSERT_NOT_NULL(question);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_PTR, "127.1.168.192.in-addr.arpa");
+        ASSERT_NOT_NULL(key);
+
+        ASSERT_EQ(dns_question_size(question), 1u);
+        ASSERT_TRUE(dns_question_contains_key(question, key));
+}
+
+/* ================================================================
+ * dns_question_new_service()
+ * ================================================================ */
+
+TEST(dns_question_new_service_no_domain) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+
+        ASSERT_ERROR(dns_question_new_service(&question, NULL, "_xmpp._tcp", NULL, 0, 0), EINVAL);
+        ASSERT_NULL(question);
+}
+
+TEST(dns_question_new_service_domain_only) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+        _cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL;
+
+        ASSERT_OK(dns_question_new_service(&question, NULL, NULL, "www.example.com", 0, 0));
+        ASSERT_NOT_NULL(question);
+        ASSERT_EQ(dns_question_size(question), 1u);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_SRV, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        ASSERT_TRUE(dns_question_contains_key(question, key));
+}
+
+TEST(dns_question_new_service_domain_ignores_idna) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+        _cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL;
+
+        ASSERT_OK(dns_question_new_service(&question, NULL, NULL, "\xF0\x9F\x98\xB1.com", 0, 1));
+        ASSERT_NOT_NULL(question);
+        ASSERT_EQ(dns_question_size(question), 1u);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_SRV, "\xF0\x9F\x98\xB1.com");
+        ASSERT_NOT_NULL(key);
+        ASSERT_TRUE(dns_question_contains_key(question, key));
+}
+
+TEST(dns_question_new_service_with_type) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+        _cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL;
+
+        ASSERT_OK(dns_question_new_service(&question, NULL, "_xmpp._tcp", "example.com", 0, 0));
+        ASSERT_NOT_NULL(question);
+        ASSERT_EQ(dns_question_size(question), 1u);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_SRV, "_xmpp._tcp.example.com");
+        ASSERT_NOT_NULL(key);
+        ASSERT_TRUE(dns_question_contains_key(question, key));
+}
+
+#if HAVE_LIBIDN || HAVE_LIBIDN2
+TEST(dns_question_new_service_with_type_applies_idna) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+        _cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL;
+
+        ASSERT_OK(dns_question_new_service(&question, NULL, "_xmpp._tcp", "\xF0\x9F\x98\xB1.com", 0, 1));
+        ASSERT_NOT_NULL(question);
+        ASSERT_EQ(dns_question_size(question), 1u);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_SRV, "_xmpp._tcp.xn--s38h.com");
+        ASSERT_NOT_NULL(key);
+        ASSERT_TRUE(dns_question_contains_key(question, key));
+}
+
+TEST(dns_question_new_service_with_type_with_txt) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+        DnsResourceKey *key = NULL;
+
+        ASSERT_OK(dns_question_new_service(&question, NULL, "_xmpp._tcp", "\xF0\x9F\x98\xB1.com", 1, 1));
+        ASSERT_NOT_NULL(question);
+        ASSERT_EQ(dns_question_size(question), 2u);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_SRV, "_xmpp._tcp.xn--s38h.com");
+        ASSERT_NOT_NULL(key);
+        ASSERT_TRUE(dns_question_contains_key(question, key));
+        dns_resource_key_unref(key);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_TXT, "_xmpp._tcp.xn--s38h.com");
+        ASSERT_NOT_NULL(key);
+        ASSERT_TRUE(dns_question_contains_key(question, key));
+        dns_resource_key_unref(key);
+}
+#endif
+
+TEST(dns_question_new_service_with_invalid_type) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+
+        ASSERT_ERROR(dns_question_new_service(&question, NULL, "_xmpp.tcp", "example.com", 0, 0), EINVAL);
+        ASSERT_NULL(question);
+}
+
+TEST(dns_question_new_service_with_type_too_short) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+
+        ASSERT_ERROR(dns_question_new_service(&question, NULL, "_xmpp", "example.com", 0, 0), EINVAL);
+        ASSERT_NULL(question);
+}
+
+TEST(dns_question_new_service_with_type_too_long) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+
+        ASSERT_ERROR(dns_question_new_service(&question, NULL, "_xmpp._tcp._extra", "example.com", 0, 0), EINVAL);
+        ASSERT_NULL(question);
+}
+
+TEST(dns_question_new_service_with_service_and_type) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+        _cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL;
+
+        ASSERT_OK(dns_question_new_service(&question, "service", "_xmpp._tcp", "example.com", 0, 0));
+        ASSERT_NOT_NULL(question);
+        ASSERT_EQ(dns_question_size(question), 1u);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_SRV, "service._xmpp._tcp.example.com");
+        ASSERT_NOT_NULL(key);
+        ASSERT_TRUE(dns_question_contains_key(question, key));
+}
+
+TEST(dns_question_new_service_with_service_no_type) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+
+        ASSERT_ERROR(dns_question_new_service(&question, "service", NULL, "example.com", 0, 0), EINVAL);
+        ASSERT_NULL(question);
+}
+
+/* ================================================================
+ * dns_question_matches_rr()
+ * ================================================================ */
+
+TEST(dns_question_matches_rr_first) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+        DnsResourceKey *key = NULL;
+        _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL;
+
+        question = dns_question_new(2);
+        ASSERT_NOT_NULL(question);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(question, key, 0);
+        dns_resource_key_unref(key);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "mail.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(question, key, 0);
+        dns_resource_key_unref(key);
+
+        rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(rr);
+        ASSERT_TRUE(dns_question_matches_rr(question, rr, NULL));
+}
+
+TEST(dns_question_matches_rr_second) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+        DnsResourceKey *key = NULL;
+        _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL;
+
+        question = dns_question_new(2);
+        ASSERT_NOT_NULL(question);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(question, key, 0);
+        dns_resource_key_unref(key);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "mail.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(question, key, 0);
+        dns_resource_key_unref(key);
+
+        rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_A, "mail.example.com");
+        ASSERT_NOT_NULL(rr);
+        ASSERT_TRUE(dns_question_matches_rr(question, rr, NULL));
+}
+
+TEST(dns_question_matches_rr_fail) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+        DnsResourceKey *key = NULL;
+        _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL;
+
+        question = dns_question_new(2);
+        ASSERT_NOT_NULL(question);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(question, key, 0);
+        dns_resource_key_unref(key);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "mail.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(question, key, 0);
+        dns_resource_key_unref(key);
+
+        rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_CNAME, "mail.example.com");
+        ASSERT_NOT_NULL(rr);
+        ASSERT_FALSE(dns_question_matches_rr(question, rr, NULL));
+}
+
+/* ================================================================
+ * dns_question_matches_cname_or_dname()
+ * ================================================================ */
+
+TEST(dns_question_matches_cname) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+        _cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL;
+        _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL;
+
+        question = dns_question_new(1);
+        ASSERT_NOT_NULL(question);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(question, key, 0);
+
+        rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_CNAME, "www.example.com");
+        ASSERT_NOT_NULL(rr);
+        ASSERT_TRUE(dns_question_matches_cname_or_dname(question, rr, NULL));
+}
+
+TEST(dns_question_matches_dname) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+        _cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL;
+        _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL;
+
+        question = dns_question_new(1);
+        ASSERT_NOT_NULL(question);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(question, key, 0);
+
+        rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_DNAME, "example.com");
+        ASSERT_NOT_NULL(rr);
+        ASSERT_TRUE(dns_question_matches_cname_or_dname(question, rr, NULL));
+}
+
+TEST(dns_question_matches_cname_or_dname_fail) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+        _cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL;
+        _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL;
+
+        question = dns_question_new(1);
+        ASSERT_NOT_NULL(question);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(question, key, 0);
+
+        rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(rr);
+        ASSERT_FALSE(dns_question_matches_cname_or_dname(question, rr, NULL));
+}
+
+TEST(dns_question_matches_cname_or_dname_all_must_redirect) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+        DnsResourceKey *key = NULL;
+        _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL;
+
+        question = dns_question_new(2);
+        ASSERT_NOT_NULL(question);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_CNAME, "example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(question, key, 0);
+        dns_resource_key_unref(key);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(question, key, 0);
+        dns_resource_key_unref(key);
+
+        rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_CNAME, "www.example.com");
+        ASSERT_NOT_NULL(rr);
+        ASSERT_FALSE(dns_question_matches_cname_or_dname(question, rr, NULL));
+}
+
+/* ================================================================
+ * dns_question_is_valid_for_query()
+ * ================================================================ */
+
+TEST(dns_question_is_valid_for_query_empty) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+
+        question = dns_question_new(0);
+        ASSERT_NOT_NULL(question);
+        ASSERT_FALSE(dns_question_is_valid_for_query(question));
+}
+
+TEST(dns_question_is_valid_for_query_single) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+        _cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL;
+
+        question = dns_question_new(1);
+        ASSERT_NOT_NULL(question);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(question, key, 0);
+
+        ASSERT_TRUE(dns_question_is_valid_for_query(question));
+}
+
+TEST(dns_question_is_valid_for_query_invalid_type) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+        _cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL;
+
+        question = dns_question_new(1);
+        ASSERT_NOT_NULL(question);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_OPT, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(question, key, 0);
+
+        ASSERT_FALSE(dns_question_is_valid_for_query(question));
+}
+
+TEST(dns_question_is_valid_for_query_multi_same_name) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+        DnsResourceKey *key = NULL;
+
+        question = dns_question_new(2);
+        ASSERT_NOT_NULL(question);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(question, key, 0);
+        dns_resource_key_unref(key);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_AAAA, "www.EXAMPLE.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(question, key, 0);
+        dns_resource_key_unref(key);
+
+        ASSERT_TRUE(dns_question_is_valid_for_query(question));
+}
+
+TEST(dns_question_is_valid_for_query_multi_different_names) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+        DnsResourceKey *key = NULL;
+
+        question = dns_question_new(2);
+        ASSERT_NOT_NULL(question);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(question, key, 0);
+        dns_resource_key_unref(key);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_AAAA, "www.example.org");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(question, key, 0);
+        dns_resource_key_unref(key);
+
+        ASSERT_FALSE(dns_question_is_valid_for_query(question));
+}
+
+/* ================================================================
+ * dns_question_is_equal()
+ * ================================================================ */
+
+TEST(dns_question_is_equal_same_pointer) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *a = NULL;
+
+        a = dns_question_new(0);
+        ASSERT_NOT_NULL(a);
+
+        ASSERT_TRUE(dns_question_is_equal(a, a));
+}
+
+TEST(dns_question_is_equal_both_empty) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *a = NULL, *b = NULL;
+
+        a = dns_question_new(0);
+        ASSERT_NOT_NULL(a);
+
+        b = dns_question_new(0);
+        ASSERT_NOT_NULL(b);
+
+        ASSERT_TRUE(dns_question_is_equal(a, b));
+}
+
+TEST(dns_question_is_equal_single) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *a = NULL, *b = NULL;
+        DnsResourceKey *key = NULL;
+
+        a = dns_question_new(1);
+        ASSERT_NOT_NULL(a);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(a, key, 0);
+        dns_resource_key_unref(key);
+
+        b = dns_question_new(1);
+        ASSERT_NOT_NULL(b);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.EXAMPLE.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(b, key, 0);
+        dns_resource_key_unref(key);
+
+        ASSERT_TRUE(dns_question_is_equal(a, b));
+}
+
+TEST(dns_question_is_equal_different_names) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *a = NULL, *b = NULL;
+        DnsResourceKey *key = NULL;
+
+        a = dns_question_new(1);
+        ASSERT_NOT_NULL(a);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(a, key, 0);
+        dns_resource_key_unref(key);
+
+        b = dns_question_new(1);
+        ASSERT_NOT_NULL(b);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.org");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(b, key, 0);
+        dns_resource_key_unref(key);
+
+        ASSERT_FALSE(dns_question_is_equal(a, b));
+}
+
+TEST(dns_question_is_equal_different_types) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *a = NULL, *b = NULL;
+        DnsResourceKey *key = NULL;
+
+        a = dns_question_new(1);
+        ASSERT_NOT_NULL(a);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(a, key, 0);
+        dns_resource_key_unref(key);
+
+        b = dns_question_new(1);
+        ASSERT_NOT_NULL(b);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_AAAA, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(b, key, 0);
+        dns_resource_key_unref(key);
+
+        ASSERT_FALSE(dns_question_is_equal(a, b));
+}
+
+TEST(dns_question_is_equal_first_larger) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *a = NULL, *b = NULL;
+        DnsResourceKey *key = NULL;
+
+        a = dns_question_new(2);
+        ASSERT_NOT_NULL(a);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(a, key, 0);
+        dns_resource_key_unref(key);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_AAAA, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(a, key, 0);
+        dns_resource_key_unref(key);
+
+        b = dns_question_new(1);
+        ASSERT_NOT_NULL(b);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(b, key, 0);
+        dns_resource_key_unref(key);
+
+        ASSERT_FALSE(dns_question_is_equal(a, b));
+}
+
+TEST(dns_question_is_equal_second_larger) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *a = NULL, *b = NULL;
+        DnsResourceKey *key = NULL;
+
+        a = dns_question_new(1);
+        ASSERT_NOT_NULL(a);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(a, key, 0);
+        dns_resource_key_unref(key);
+
+        b = dns_question_new(2);
+        ASSERT_NOT_NULL(b);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(b, key, 0);
+        dns_resource_key_unref(key);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_AAAA, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(b, key, 0);
+        dns_resource_key_unref(key);
+
+        ASSERT_FALSE(dns_question_is_equal(a, b));
+}
+
+TEST(dns_question_is_equal_different_order) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *a = NULL, *b = NULL;
+        DnsResourceKey *key = NULL;
+
+        a = dns_question_new(2);
+        ASSERT_NOT_NULL(a);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_AAAA, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(a, key, 0);
+        dns_resource_key_unref(key);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(a, key, 0);
+        dns_resource_key_unref(key);
+
+        b = dns_question_new(2);
+        ASSERT_NOT_NULL(b);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(b, key, 0);
+        dns_resource_key_unref(key);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_AAAA, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(b, key, 0);
+        dns_resource_key_unref(key);
+
+        ASSERT_TRUE(dns_question_is_equal(a, b));
+}
+
+/* ================================================================
+ * dns_question_cname_redirect()
+ * ================================================================ */
+
+TEST(dns_question_cname_redirect_empty) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL, *ret = NULL;
+        _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL;
+
+        question = dns_question_new(0);
+        ASSERT_NOT_NULL(question);
+
+        rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_CNAME, "www.example.com");
+        ASSERT_NOT_NULL(rr);
+        rr->cname.name = strdup("example.com");
+
+        ASSERT_FALSE(dns_question_cname_redirect(question, rr, &ret));
+        ASSERT_NULL(ret);
+}
+
+TEST(dns_question_cname_redirect_single_cname_match) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL, *ret = NULL;
+        DnsResourceKey *key = NULL;
+        _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL;
+
+        question = dns_question_new(1);
+        ASSERT_NOT_NULL(question);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(question, key, 0);
+        dns_resource_key_unref(key);
+
+        rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_CNAME, "www.example.com");
+        ASSERT_NOT_NULL(rr);
+        rr->cname.name = strdup("example.com");
+
+        ASSERT_TRUE(dns_question_cname_redirect(question, rr, &ret));
+
+        ASSERT_NOT_NULL(ret);
+        ASSERT_TRUE(question != ret);
+        ASSERT_FALSE(dns_question_is_equal(question, ret));
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        ASSERT_TRUE(dns_question_contains_key(question, key));
+        dns_resource_key_unref(key);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "example.com");
+        ASSERT_NOT_NULL(key);
+        ASSERT_TRUE(dns_question_contains_key(ret, key));
+        dns_resource_key_unref(key);
+}
+
+TEST(dns_question_cname_redirect_single_cname_no_change) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL, *ret = NULL;
+        DnsResourceKey *key = NULL;
+        _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL;
+
+        question = dns_question_new(1);
+        ASSERT_NOT_NULL(question);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(question, key, 0);
+        dns_resource_key_unref(key);
+
+        rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_CNAME, "www.example.com");
+        ASSERT_NOT_NULL(rr);
+        rr->cname.name = strdup("example.com");
+
+        ASSERT_FALSE(dns_question_cname_redirect(question, rr, &ret));
+        ASSERT_NULL(ret);
+}
+
+TEST(dns_question_cname_redirect_single_cname_no_match) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL, *ret = NULL;
+        DnsResourceKey *key = NULL;
+        _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL;
+
+        question = dns_question_new(1);
+        ASSERT_NOT_NULL(question);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "mail.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(question, key, 0);
+        dns_resource_key_unref(key);
+
+        rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_CNAME, "www.example.com");
+        ASSERT_NOT_NULL(rr);
+        rr->cname.name = strdup("example.com");
+
+        ASSERT_TRUE(dns_question_cname_redirect(question, rr, &ret));
+
+        ASSERT_NOT_NULL(ret);
+        ASSERT_TRUE(question != ret);
+        ASSERT_FALSE(dns_question_is_equal(question, ret));
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "mail.example.com");
+        ASSERT_NOT_NULL(key);
+        ASSERT_TRUE(dns_question_contains_key(question, key));
+        dns_resource_key_unref(key);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "example.com");
+        ASSERT_NOT_NULL(key);
+        ASSERT_TRUE(dns_question_contains_key(ret, key));
+        dns_resource_key_unref(key);
+}
+
+TEST(dns_question_cname_redirect_single_dname_match) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL, *ret = NULL;
+        DnsResourceKey *key = NULL;
+        _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL;
+
+        question = dns_question_new(1);
+        ASSERT_NOT_NULL(question);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(question, key, 0);
+        dns_resource_key_unref(key);
+
+        rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_DNAME, "example.com");
+        ASSERT_NOT_NULL(rr);
+        rr->cname.name = strdup("v2.example.com");
+
+        ASSERT_TRUE(dns_question_cname_redirect(question, rr, &ret));
+
+        ASSERT_NOT_NULL(ret);
+        ASSERT_TRUE(question != ret);
+        ASSERT_FALSE(dns_question_is_equal(question, ret));
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        ASSERT_TRUE(dns_question_contains_key(question, key));
+        dns_resource_key_unref(key);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.v2.example.com");
+        ASSERT_NOT_NULL(key);
+        ASSERT_TRUE(dns_question_contains_key(ret, key));
+        dns_resource_key_unref(key);
+}
+
+TEST(dns_question_cname_redirect_multi_dname_match) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL, *ret = NULL;
+        DnsResourceKey *key = NULL;
+        _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL;
+
+        question = dns_question_new(2);
+        ASSERT_NOT_NULL(question);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(question, key, 0);
+        dns_resource_key_unref(key);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "mail.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(question, key, 0);
+        dns_resource_key_unref(key);
+
+        rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_DNAME, "example.com");
+        ASSERT_NOT_NULL(rr);
+        rr->cname.name = strdup("v2.example.com");
+
+        ASSERT_TRUE(dns_question_cname_redirect(question, rr, &ret));
+
+        ASSERT_NOT_NULL(ret);
+        ASSERT_TRUE(question != ret);
+        ASSERT_FALSE(dns_question_is_equal(question, ret));
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.v2.example.com");
+        ASSERT_NOT_NULL(key);
+        ASSERT_TRUE(dns_question_contains_key(ret, key));
+        dns_resource_key_unref(key);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "mail.v2.example.com");
+        ASSERT_NOT_NULL(key);
+        ASSERT_TRUE(dns_question_contains_key(ret, key));
+        dns_resource_key_unref(key);
+}
+
+/* ================================================================
+ * dns_question_dump()
+ * ================================================================ */
+
+static void check_dump_contents(FILE *f, const char **expected, size_t n) {
+        char *actual[n];
+        size_t i, r;
+        rewind(f);
+
+        for (i = 0; i < n; i++) {
+                r = read_line(f, 1024, &actual[i]);
+                ASSERT_GT(r, 0u);
+        }
+
+        for (i = 0; i < n; i++)
+                ASSERT_STREQ(actual[i], expected[i]);
+
+        for (i = 0; i < n; i++)
+                free(actual[i]);
+}
+
+TEST(dns_question_dump) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+        DnsResourceKey *key = NULL;
+
+        question = dns_question_new(3);
+        ASSERT_NOT_NULL(question);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(question, key, 0);
+        dns_resource_key_unref(key);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_AAAA, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(question, key, 0);
+        dns_resource_key_unref(key);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_TXT, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(question, key, 0);
+        dns_resource_key_unref(key);
+
+        ASSERT_EQ(dns_question_size(question), 3u);
+
+        _cleanup_(unlink_tempfilep) char p[] = "/tmp/dns-question-dump-XXXXXX";
+        _cleanup_fclose_ FILE *f = NULL;
+        fmkostemp_safe(p, "r+", &f);
+        dns_question_dump(question, f);
+
+        const char *expected[] = {
+                "\twww.example.com IN A",
+                "\twww.example.com IN AAAA",
+                "\twww.example.com IN TXT"
+        };
+        check_dump_contents(f, expected, 3);
+}
+
+/* ================================================================
+ * dns_question_first_name()
+ * ================================================================ */
+
+TEST(dns_question_first_name_empty) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+        const char *name = NULL;
+
+        question = dns_question_new(0);
+        ASSERT_NOT_NULL(question);
+
+        name = dns_question_first_name(question);
+        ASSERT_NULL(name);
+}
+
+TEST(dns_question_first_name_multi) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+        DnsResourceKey *key = NULL;
+        const char *name = NULL;
+
+        question = dns_question_new(2);
+        ASSERT_NOT_NULL(question);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(question, key, 0);
+        dns_resource_key_unref(key);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "mail.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(question, key, 0);
+        dns_resource_key_unref(key);
+
+        name = dns_question_first_name(question);
+        ASSERT_STREQ(name, "www.example.com");
+}
+
+/* ================================================================
+ * dns_question_merge()
+ * ================================================================ */
+
+TEST(dns_question_merge_empty_first) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *a = NULL, *b = NULL, *ret = NULL;
+        DnsResourceKey *key = NULL;
+
+        a = dns_question_new(0);
+        ASSERT_NOT_NULL(a);
+
+        b = dns_question_new(1);
+        ASSERT_NOT_NULL(b);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(b, key, 0);
+        dns_resource_key_unref(key);
+
+        ASSERT_OK(dns_question_merge(a, b, &ret));
+        ASSERT_TRUE(ret == b);
+}
+
+TEST(dns_question_merge_empty_second) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *a = NULL, *b = NULL, *ret = NULL;
+        DnsResourceKey *key = NULL;
+
+        a = dns_question_new(1);
+        ASSERT_NOT_NULL(a);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(a, key, 0);
+        dns_resource_key_unref(key);
+
+        b = dns_question_new(0);
+        ASSERT_NOT_NULL(b);
+
+        ASSERT_OK(dns_question_merge(a, b, &ret));
+        ASSERT_TRUE(ret == a);
+}
+
+TEST(dns_question_merge_multi) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *a = NULL, *b = NULL, *ret = NULL;
+        DnsResourceKey *key = NULL;
+        int i;
+        uint16_t types[3];
+
+        a = dns_question_new(1);
+        ASSERT_NOT_NULL(a);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(a, key, 0);
+        dns_resource_key_unref(key);
+
+        b = dns_question_new(2);
+        ASSERT_NOT_NULL(b);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_AAAA, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(b, key, 0);
+        dns_resource_key_unref(key);
+
+        key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_TXT, "www.example.com");
+        ASSERT_NOT_NULL(key);
+        dns_question_add(b, key, 0);
+        dns_resource_key_unref(key);
+
+        ASSERT_OK(dns_question_merge(a, b, &ret));
+        ASSERT_TRUE(ret != a);
+        ASSERT_TRUE(ret != b);
+
+        ASSERT_EQ(dns_question_size(a), 1u);
+        ASSERT_EQ(dns_question_size(b), 2u);
+        ASSERT_EQ(dns_question_size(ret), 3u);
+
+        i = 0;
+        DNS_QUESTION_FOREACH(key, ret) {
+                types[i++] = key->type;
+        }
+
+        ASSERT_EQ(types[0], DNS_TYPE_A);
+        ASSERT_EQ(types[1], DNS_TYPE_AAAA);
+        ASSERT_EQ(types[2], DNS_TYPE_TXT);
+}
+
+DEFINE_TEST_MAIN(LOG_DEBUG);