Adding upstream version 241.upstream/241upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1819 insertions, 0 deletions

diff --git a/src/resolve/resolved-dns-rr.c b/src/resolve/resolved-dns-rr.c
new file mode 100644
index 0000000..a1dffb0
--- /dev/null
+++ b/src/resolve/resolved-dns-rr.c
@@ -0,0 +1,1819 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
+
+#include <math.h>
+
+#include "alloc-util.h"
+#include "dns-domain.h"
+#include "dns-type.h"
+#include "escape.h"
+#include "hexdecoct.h"
+#include "resolved-dns-dnssec.h"
+#include "resolved-dns-packet.h"
+#include "resolved-dns-rr.h"
+#include "string-table.h"
+#include "string-util.h"
+#include "strv.h"
+#include "terminal-util.h"
+
+DnsResourceKey* dns_resource_key_new(uint16_t class, uint16_t type, const char *name) {
+        DnsResourceKey *k;
+        size_t l;
+
+        assert(name);
+
+        l = strlen(name);
+        k = malloc0(sizeof(DnsResourceKey) + l + 1);
+        if (!k)
+                return NULL;
+
+        k->n_ref = 1;
+        k->class = class;
+        k->type = type;
+
+        strcpy((char*) k + sizeof(DnsResourceKey), name);
+
+        return k;
+}
+
+DnsResourceKey* dns_resource_key_new_redirect(const DnsResourceKey *key, const DnsResourceRecord *cname) {
+        int r;
+
+        assert(key);
+        assert(cname);
+
+        assert(IN_SET(cname->key->type, DNS_TYPE_CNAME, DNS_TYPE_DNAME));
+
+        if (cname->key->type == DNS_TYPE_CNAME)
+                return dns_resource_key_new(key->class, key->type, cname->cname.name);
+        else {
+                DnsResourceKey *k;
+                char *destination = NULL;
+
+                r = dns_name_change_suffix(dns_resource_key_name(key), dns_resource_key_name(cname->key), cname->dname.name, &destination);
+                if (r < 0)
+                        return NULL;
+                if (r == 0)
+                        return dns_resource_key_ref((DnsResourceKey*) key);
+
+                k = dns_resource_key_new_consume(key->class, key->type, destination);
+                if (!k)
+                        return mfree(destination);
+
+                return k;
+        }
+}
+
+int dns_resource_key_new_append_suffix(DnsResourceKey **ret, DnsResourceKey *key, char *name) {
+        DnsResourceKey *new_key;
+        char *joined;
+        int r;
+
+        assert(ret);
+        assert(key);
+        assert(name);
+
+        if (dns_name_is_root(name)) {
+                *ret = dns_resource_key_ref(key);
+                return 0;
+        }
+
+        r = dns_name_concat(dns_resource_key_name(key), name, 0, &joined);
+        if (r < 0)
+                return r;
+
+        new_key = dns_resource_key_new_consume(key->class, key->type, joined);
+        if (!new_key) {
+                free(joined);
+                return -ENOMEM;
+        }
+
+        *ret = new_key;
+        return 0;
+}
+
+DnsResourceKey* dns_resource_key_new_consume(uint16_t class, uint16_t type, char *name) {
+        DnsResourceKey *k;
+
+        assert(name);
+
+        k = new0(DnsResourceKey, 1);
+        if (!k)
+                return NULL;
+
+        k->n_ref = 1;
+        k->class = class;
+        k->type = type;
+        k->_name = name;
+
+        return k;
+}
+
+DnsResourceKey* dns_resource_key_ref(DnsResourceKey *k) {
+
+        if (!k)
+                return NULL;
+
+        /* Static/const keys created with DNS_RESOURCE_KEY_CONST will
+         * set this to -1, they should not be reffed/unreffed */
+        assert(k->n_ref != (unsigned) -1);
+
+        assert(k->n_ref > 0);
+        k->n_ref++;
+
+        return k;
+}
+
+DnsResourceKey* dns_resource_key_unref(DnsResourceKey *k) {
+        if (!k)
+                return NULL;
+
+        assert(k->n_ref != (unsigned) -1);
+        assert(k->n_ref > 0);
+
+        if (k->n_ref == 1) {
+                free(k->_name);
+                free(k);
+        } else
+                k->n_ref--;
+
+        return NULL;
+}
+
+const char* dns_resource_key_name(const DnsResourceKey *key) {
+        const char *name;
+
+        if (!key)
+                return NULL;
+
+        if (key->_name)
+                name = key->_name;
+        else
+                name = (char*) key + sizeof(DnsResourceKey);
+
+        if (dns_name_is_root(name))
+                return ".";
+        else
+                return name;
+}
+
+bool dns_resource_key_is_address(const DnsResourceKey *key) {
+        assert(key);
+
+        /* Check if this is an A or AAAA resource key */
+
+        return key->class == DNS_CLASS_IN && IN_SET(key->type, DNS_TYPE_A, DNS_TYPE_AAAA);
+}
+
+bool dns_resource_key_is_dnssd_ptr(const DnsResourceKey *key) {
+        assert(key);
+
+        /* Check if this is a PTR resource key used in
+           Service Instance Enumeration as described in RFC6763 p4.1. */
+
+        if (key->type != DNS_TYPE_PTR)
+                return false;
+
+        return dns_name_endswith(dns_resource_key_name(key), "_tcp.local") ||
+                dns_name_endswith(dns_resource_key_name(key), "_udp.local");
+}
+
+int dns_resource_key_equal(const DnsResourceKey *a, const DnsResourceKey *b) {
+        int r;
+
+        if (a == b)
+                return 1;
+
+        r = dns_name_equal(dns_resource_key_name(a), dns_resource_key_name(b));
+        if (r <= 0)
+                return r;
+
+        if (a->class != b->class)
+                return 0;
+
+        if (a->type != b->type)
+                return 0;
+
+        return 1;
+}
+
+int dns_resource_key_match_rr(const DnsResourceKey *key, DnsResourceRecord *rr, const char *search_domain) {
+        int r;
+
+        assert(key);
+        assert(rr);
+
+        if (key == rr->key)
+                return 1;
+
+        /* Checks if an rr matches the specified key. If a search
+         * domain is specified, it will also be checked if the key
+         * with the search domain suffixed might match the RR. */
+
+        if (rr->key->class != key->class && key->class != DNS_CLASS_ANY)
+                return 0;
+
+        if (rr->key->type != key->type && key->type != DNS_TYPE_ANY)
+                return 0;
+
+        r = dns_name_equal(dns_resource_key_name(rr->key), dns_resource_key_name(key));
+        if (r != 0)
+                return r;
+
+        if (search_domain) {
+                _cleanup_free_ char *joined = NULL;
+
+                r = dns_name_concat(dns_resource_key_name(key), search_domain, 0, &joined);
+                if (r < 0)
+                        return r;
+
+                return dns_name_equal(dns_resource_key_name(rr->key), joined);
+        }
+
+        return 0;
+}
+
+int dns_resource_key_match_cname_or_dname(const DnsResourceKey *key, const DnsResourceKey *cname, const char *search_domain) {
+        int r;
+
+        assert(key);
+        assert(cname);
+
+        if (cname->class != key->class && key->class != DNS_CLASS_ANY)
+                return 0;
+
+        if (cname->type == DNS_TYPE_CNAME)
+                r = dns_name_equal(dns_resource_key_name(key), dns_resource_key_name(cname));
+        else if (cname->type == DNS_TYPE_DNAME)
+                r = dns_name_endswith(dns_resource_key_name(key), dns_resource_key_name(cname));
+        else
+                return 0;
+
+        if (r != 0)
+                return r;
+
+        if (search_domain) {
+                _cleanup_free_ char *joined = NULL;
+
+                r = dns_name_concat(dns_resource_key_name(key), search_domain, 0, &joined);
+                if (r < 0)
+                        return r;
+
+                if (cname->type == DNS_TYPE_CNAME)
+                        return dns_name_equal(joined, dns_resource_key_name(cname));
+                else if (cname->type == DNS_TYPE_DNAME)
+                        return dns_name_endswith(joined, dns_resource_key_name(cname));
+        }
+
+        return 0;
+}
+
+int dns_resource_key_match_soa(const DnsResourceKey *key, const DnsResourceKey *soa) {
+        assert(soa);
+        assert(key);
+
+        /* Checks whether 'soa' is a SOA record for the specified key. */
+
+        if (soa->class != key->class)
+                return 0;
+
+        if (soa->type != DNS_TYPE_SOA)
+                return 0;
+
+        return dns_name_endswith(dns_resource_key_name(key), dns_resource_key_name(soa));
+}
+
+static void dns_resource_key_hash_func(const DnsResourceKey *k, struct siphash *state) {
+        assert(k);
+
+        dns_name_hash_func(dns_resource_key_name(k), state);
+        siphash24_compress(&k->class, sizeof(k->class), state);
+        siphash24_compress(&k->type, sizeof(k->type), state);
+}
+
+static int dns_resource_key_compare_func(const DnsResourceKey *x, const DnsResourceKey *y) {
+        int ret;
+
+        ret = dns_name_compare_func(dns_resource_key_name(x), dns_resource_key_name(y));
+        if (ret != 0)
+                return ret;
+
+        ret = CMP(x->type, y->type);
+        if (ret != 0)
+                return ret;
+
+        ret = CMP(x->class, y->class);
+        if (ret != 0)
+                return ret;
+
+        return 0;
+}
+
+DEFINE_HASH_OPS(dns_resource_key_hash_ops, DnsResourceKey, dns_resource_key_hash_func, dns_resource_key_compare_func);
+
+char* dns_resource_key_to_string(const DnsResourceKey *key, char *buf, size_t buf_size) {
+        const char *c, *t;
+        char *ans = buf;
+
+        /* If we cannot convert the CLASS/TYPE into a known string,
+           use the format recommended by RFC 3597, Section 5. */
+
+        c = dns_class_to_string(key->class);
+        t = dns_type_to_string(key->type);
+
+        snprintf(buf, buf_size, "%s %s%s%.0u %s%s%.0u",
+                 dns_resource_key_name(key),
+                 strempty(c), c ? "" : "CLASS", c ? 0 : key->class,
+                 strempty(t), t ? "" : "TYPE", t ? 0 : key->type);
+
+        return ans;
+}
+
+bool dns_resource_key_reduce(DnsResourceKey **a, DnsResourceKey **b) {
+        assert(a);
+        assert(b);
+
+        /* Try to replace one RR key by another if they are identical, thus saving a bit of memory. Note that we do
+         * this only for RR keys, not for RRs themselves, as they carry a lot of additional metadata (where they come
+         * from, validity data, and suchlike), and cannot be replaced so easily by other RRs that have the same
+         * superficial data. */
+
+        if (!*a)
+                return false;
+        if (!*b)
+                return false;
+
+        /* We refuse merging const keys */
+        if ((*a)->n_ref == (unsigned) -1)
+                return false;
+        if ((*b)->n_ref == (unsigned) -1)
+                return false;
+
+        /* Already the same? */
+        if (*a == *b)
+                return true;
+
+        /* Are they really identical? */
+        if (dns_resource_key_equal(*a, *b) <= 0)
+                return false;
+
+        /* Keep the one which already has more references. */
+        if ((*a)->n_ref > (*b)->n_ref) {
+                dns_resource_key_unref(*b);
+                *b = dns_resource_key_ref(*a);
+        } else {
+                dns_resource_key_unref(*a);
+                *a = dns_resource_key_ref(*b);
+        }
+
+        return true;
+}
+
+DnsResourceRecord* dns_resource_record_new(DnsResourceKey *key) {
+        DnsResourceRecord *rr;
+
+        rr = new0(DnsResourceRecord, 1);
+        if (!rr)
+                return NULL;
+
+        rr->n_ref = 1;
+        rr->key = dns_resource_key_ref(key);
+        rr->expiry = USEC_INFINITY;
+        rr->n_skip_labels_signer = rr->n_skip_labels_source = (unsigned) -1;
+
+        return rr;
+}
+
+DnsResourceRecord* dns_resource_record_new_full(uint16_t class, uint16_t type, const char *name) {
+        _cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL;
+
+        key = dns_resource_key_new(class, type, name);
+        if (!key)
+                return NULL;
+
+        return dns_resource_record_new(key);
+}
+
+static DnsResourceRecord* dns_resource_record_free(DnsResourceRecord *rr) {
+        assert(rr);
+
+        if (rr->key) {
+                switch(rr->key->type) {
+
+                case DNS_TYPE_SRV:
+                        free(rr->srv.name);
+                        break;
+
+                case DNS_TYPE_PTR:
+                case DNS_TYPE_NS:
+                case DNS_TYPE_CNAME:
+                case DNS_TYPE_DNAME:
+                        free(rr->ptr.name);
+                        break;
+
+                case DNS_TYPE_HINFO:
+                        free(rr->hinfo.cpu);
+                        free(rr->hinfo.os);
+                        break;
+
+                case DNS_TYPE_TXT:
+                case DNS_TYPE_SPF:
+                        dns_txt_item_free_all(rr->txt.items);
+                        break;
+
+                case DNS_TYPE_SOA:
+                        free(rr->soa.mname);
+                        free(rr->soa.rname);
+                        break;
+
+                case DNS_TYPE_MX:
+                        free(rr->mx.exchange);
+                        break;
+
+                case DNS_TYPE_DS:
+                        free(rr->ds.digest);
+                        break;
+
+                case DNS_TYPE_SSHFP:
+                        free(rr->sshfp.fingerprint);
+                        break;
+
+                case DNS_TYPE_DNSKEY:
+                        free(rr->dnskey.key);
+                        break;
+
+                case DNS_TYPE_RRSIG:
+                        free(rr->rrsig.signer);
+                        free(rr->rrsig.signature);
+                        break;
+
+                case DNS_TYPE_NSEC:
+                        free(rr->nsec.next_domain_name);
+                        bitmap_free(rr->nsec.types);
+                        break;
+
+                case DNS_TYPE_NSEC3:
+                        free(rr->nsec3.next_hashed_name);
+                        free(rr->nsec3.salt);
+                        bitmap_free(rr->nsec3.types);
+                        break;
+
+                case DNS_TYPE_LOC:
+                case DNS_TYPE_A:
+                case DNS_TYPE_AAAA:
+                        break;
+
+                case DNS_TYPE_TLSA:
+                        free(rr->tlsa.data);
+                        break;
+
+                case DNS_TYPE_CAA:
+                        free(rr->caa.tag);
+                        free(rr->caa.value);
+                        break;
+
+                case DNS_TYPE_OPENPGPKEY:
+                default:
+                        if (!rr->unparseable)
+                                free(rr->generic.data);
+                }
+
+                if (rr->unparseable)
+                        free(rr->generic.data);
+
+                free(rr->wire_format);
+                dns_resource_key_unref(rr->key);
+        }
+
+        free(rr->to_string);
+        return mfree(rr);
+}
+
+DEFINE_TRIVIAL_REF_UNREF_FUNC(DnsResourceRecord, dns_resource_record, dns_resource_record_free);
+
+int dns_resource_record_new_reverse(DnsResourceRecord **ret, int family, const union in_addr_union *address, const char *hostname) {
+        _cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL;
+        _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL;
+        _cleanup_free_ char *ptr = NULL;
+        int r;
+
+        assert(ret);
+        assert(address);
+        assert(hostname);
+
+        r = dns_name_reverse(family, address, &ptr);
+        if (r < 0)
+                return r;
+
+        key = dns_resource_key_new_consume(DNS_CLASS_IN, DNS_TYPE_PTR, ptr);
+        if (!key)
+                return -ENOMEM;
+
+        ptr = NULL;
+
+        rr = dns_resource_record_new(key);
+        if (!rr)
+                return -ENOMEM;
+
+        rr->ptr.name = strdup(hostname);
+        if (!rr->ptr.name)
+                return -ENOMEM;
+
+        *ret = TAKE_PTR(rr);
+
+        return 0;
+}
+
+int dns_resource_record_new_address(DnsResourceRecord **ret, int family, const union in_addr_union *address, const char *name) {
+        DnsResourceRecord *rr;
+
+        assert(ret);
+        assert(address);
+        assert(family);
+
+        if (family == AF_INET) {
+
+                rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_A, name);
+                if (!rr)
+                        return -ENOMEM;
+
+                rr->a.in_addr = address->in;
+
+        } else if (family == AF_INET6) {
+
+                rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_AAAA, name);
+                if (!rr)
+                        return -ENOMEM;
+
+                rr->aaaa.in6_addr = address->in6;
+        } else
+                return -EAFNOSUPPORT;
+
+        *ret = rr;
+
+        return 0;
+}
+
+#define FIELD_EQUAL(a, b, field) \
+        ((a).field ## _size == (b).field ## _size &&  \
+         memcmp((a).field, (b).field, (a).field ## _size) == 0)
+
+int dns_resource_record_equal(const DnsResourceRecord *a, const DnsResourceRecord *b) {
+        int r;
+
+        assert(a);
+        assert(b);
+
+        if (a == b)
+                return 1;
+
+        r = dns_resource_key_equal(a->key, b->key);
+        if (r <= 0)
+                return r;
+
+        if (a->unparseable != b->unparseable)
+                return 0;
+
+        switch (a->unparseable ? _DNS_TYPE_INVALID : a->key->type) {
+
+        case DNS_TYPE_SRV:
+                r = dns_name_equal(a->srv.name, b->srv.name);
+                if (r <= 0)
+                        return r;
+
+                return a->srv.priority == b->srv.priority &&
+                       a->srv.weight == b->srv.weight &&
+                       a->srv.port == b->srv.port;
+
+        case DNS_TYPE_PTR:
+        case DNS_TYPE_NS:
+        case DNS_TYPE_CNAME:
+        case DNS_TYPE_DNAME:
+                return dns_name_equal(a->ptr.name, b->ptr.name);
+
+        case DNS_TYPE_HINFO:
+                return strcaseeq(a->hinfo.cpu, b->hinfo.cpu) &&
+                       strcaseeq(a->hinfo.os, b->hinfo.os);
+
+        case DNS_TYPE_SPF: /* exactly the same as TXT */
+        case DNS_TYPE_TXT:
+                return dns_txt_item_equal(a->txt.items, b->txt.items);
+
+        case DNS_TYPE_A:
+                return memcmp(&a->a.in_addr, &b->a.in_addr, sizeof(struct in_addr)) == 0;
+
+        case DNS_TYPE_AAAA:
+                return memcmp(&a->aaaa.in6_addr, &b->aaaa.in6_addr, sizeof(struct in6_addr)) == 0;
+
+        case DNS_TYPE_SOA:
+                r = dns_name_equal(a->soa.mname, b->soa.mname);
+                if (r <= 0)
+                        return r;
+                r = dns_name_equal(a->soa.rname, b->soa.rname);
+                if (r <= 0)
+                        return r;
+
+                return a->soa.serial  == b->soa.serial &&
+                       a->soa.refresh == b->soa.refresh &&
+                       a->soa.retry   == b->soa.retry &&
+                       a->soa.expire  == b->soa.expire &&
+                       a->soa.minimum == b->soa.minimum;
+
+        case DNS_TYPE_MX:
+                if (a->mx.priority != b->mx.priority)
+                        return 0;
+
+                return dns_name_equal(a->mx.exchange, b->mx.exchange);
+
+        case DNS_TYPE_LOC:
+                assert(a->loc.version == b->loc.version);
+
+                return a->loc.size == b->loc.size &&
+                       a->loc.horiz_pre == b->loc.horiz_pre &&
+                       a->loc.vert_pre == b->loc.vert_pre &&
+                       a->loc.latitude == b->loc.latitude &&
+                       a->loc.longitude == b->loc.longitude &&
+                       a->loc.altitude == b->loc.altitude;
+
+        case DNS_TYPE_DS:
+                return a->ds.key_tag == b->ds.key_tag &&
+                       a->ds.algorithm == b->ds.algorithm &&
+                       a->ds.digest_type == b->ds.digest_type &&
+                       FIELD_EQUAL(a->ds, b->ds, digest);
+
+        case DNS_TYPE_SSHFP:
+                return a->sshfp.algorithm == b->sshfp.algorithm &&
+                       a->sshfp.fptype == b->sshfp.fptype &&
+                       FIELD_EQUAL(a->sshfp, b->sshfp, fingerprint);
+
+        case DNS_TYPE_DNSKEY:
+                return a->dnskey.flags == b->dnskey.flags &&
+                       a->dnskey.protocol == b->dnskey.protocol &&
+                       a->dnskey.algorithm == b->dnskey.algorithm &&
+                       FIELD_EQUAL(a->dnskey, b->dnskey, key);
+
+        case DNS_TYPE_RRSIG:
+                /* do the fast comparisons first */
+                return a->rrsig.type_covered == b->rrsig.type_covered &&
+                       a->rrsig.algorithm == b->rrsig.algorithm &&
+                       a->rrsig.labels == b->rrsig.labels &&
+                       a->rrsig.original_ttl == b->rrsig.original_ttl &&
+                       a->rrsig.expiration == b->rrsig.expiration &&
+                       a->rrsig.inception == b->rrsig.inception &&
+                       a->rrsig.key_tag == b->rrsig.key_tag &&
+                       FIELD_EQUAL(a->rrsig, b->rrsig, signature) &&
+                       dns_name_equal(a->rrsig.signer, b->rrsig.signer);
+
+        case DNS_TYPE_NSEC:
+                return dns_name_equal(a->nsec.next_domain_name, b->nsec.next_domain_name) &&
+                       bitmap_equal(a->nsec.types, b->nsec.types);
+
+        case DNS_TYPE_NSEC3:
+                return a->nsec3.algorithm == b->nsec3.algorithm &&
+                       a->nsec3.flags == b->nsec3.flags &&
+                       a->nsec3.iterations == b->nsec3.iterations &&
+                       FIELD_EQUAL(a->nsec3, b->nsec3, salt) &&
+                       FIELD_EQUAL(a->nsec3, b->nsec3, next_hashed_name) &&
+                       bitmap_equal(a->nsec3.types, b->nsec3.types);
+
+        case DNS_TYPE_TLSA:
+                return a->tlsa.cert_usage == b->tlsa.cert_usage &&
+                       a->tlsa.selector == b->tlsa.selector &&
+                       a->tlsa.matching_type == b->tlsa.matching_type &&
+                       FIELD_EQUAL(a->tlsa, b->tlsa, data);
+
+        case DNS_TYPE_CAA:
+                return a->caa.flags == b->caa.flags &&
+                       streq(a->caa.tag, b->caa.tag) &&
+                       FIELD_EQUAL(a->caa, b->caa, value);
+
+        case DNS_TYPE_OPENPGPKEY:
+        default:
+                return FIELD_EQUAL(a->generic, b->generic, data);
+        }
+}
+
+static char* format_location(uint32_t latitude, uint32_t longitude, uint32_t altitude,
+                             uint8_t size, uint8_t horiz_pre, uint8_t vert_pre) {
+        char *s;
+        char NS = latitude >= 1U<<31 ? 'N' : 'S';
+        char EW = longitude >= 1U<<31 ? 'E' : 'W';
+
+        int lat = latitude >= 1U<<31 ? (int) (latitude - (1U<<31)) : (int) ((1U<<31) - latitude);
+        int lon = longitude >= 1U<<31 ? (int) (longitude - (1U<<31)) : (int) ((1U<<31) - longitude);
+        double alt = altitude >= 10000000u ? altitude - 10000000u : -(double)(10000000u - altitude);
+        double siz = (size >> 4) * exp10((double) (size & 0xF));
+        double hor = (horiz_pre >> 4) * exp10((double) (horiz_pre & 0xF));
+        double ver = (vert_pre >> 4) * exp10((double) (vert_pre & 0xF));
+
+        if (asprintf(&s, "%d %d %.3f %c %d %d %.3f %c %.2fm %.2fm %.2fm %.2fm",
+                     (lat / 60000 / 60),
+                     (lat / 60000) % 60,
+                     (lat % 60000) / 1000.,
+                     NS,
+                     (lon / 60000 / 60),
+                     (lon / 60000) % 60,
+                     (lon % 60000) / 1000.,
+                     EW,
+                     alt / 100.,
+                     siz / 100.,
+                     hor / 100.,
+                     ver / 100.) < 0)
+                return NULL;
+
+        return s;
+}
+
+static int format_timestamp_dns(char *buf, size_t l, time_t sec) {
+        struct tm tm;
+
+        assert(buf);
+        assert(l > STRLEN("YYYYMMDDHHmmSS"));
+
+        if (!gmtime_r(&sec, &tm))
+                return -EINVAL;
+
+        if (strftime(buf, l, "%Y%m%d%H%M%S", &tm) <= 0)
+                return -EINVAL;
+
+        return 0;
+}
+
+static char *format_types(Bitmap *types) {
+        _cleanup_strv_free_ char **strv = NULL;
+        _cleanup_free_ char *str = NULL;
+        Iterator i;
+        unsigned type;
+        int r;
+
+        BITMAP_FOREACH(type, types, i) {
+                if (dns_type_to_string(type)) {
+                        r = strv_extend(&strv, dns_type_to_string(type));
+                        if (r < 0)
+                                return NULL;
+                } else {
+                        char *t;
+
+                        r = asprintf(&t, "TYPE%u", type);
+                        if (r < 0)
+                                return NULL;
+
+                        r = strv_consume(&strv, t);
+                        if (r < 0)
+                                return NULL;
+                }
+        }
+
+        str = strv_join(strv, " ");
+        if (!str)
+                return NULL;
+
+        return strjoin("( ", str, " )");
+}
+
+static char *format_txt(DnsTxtItem *first) {
+        DnsTxtItem *i;
+        size_t c = 1;
+        char *p, *s;
+
+        LIST_FOREACH(items, i, first)
+                c += i->length * 4 + 3;
+
+        p = s = new(char, c);
+        if (!s)
+                return NULL;
+
+        LIST_FOREACH(items, i, first) {
+                size_t j;
+
+                if (i != first)
+                        *(p++) = ' ';
+
+                *(p++) = '"';
+
+                for (j = 0; j < i->length; j++) {
+                        if (i->data[j] < ' ' || i->data[j] == '"' || i->data[j] >= 127) {
+                                *(p++) = '\\';
+                                *(p++) = '0' + (i->data[j] / 100);
+                                *(p++) = '0' + ((i->data[j] / 10) % 10);
+                                *(p++) = '0' + (i->data[j] % 10);
+                        } else
+                                *(p++) = i->data[j];
+                }
+
+                *(p++) = '"';
+        }
+
+        *p = 0;
+        return s;
+}
+
+const char *dns_resource_record_to_string(DnsResourceRecord *rr) {
+        _cleanup_free_ char *t = NULL;
+        char *s, k[DNS_RESOURCE_KEY_STRING_MAX];
+        int r;
+
+        assert(rr);
+
+        if (rr->to_string)
+                return rr->to_string;
+
+        dns_resource_key_to_string(rr->key, k, sizeof(k));
+
+        switch (rr->unparseable ? _DNS_TYPE_INVALID : rr->key->type) {
+
+        case DNS_TYPE_SRV:
+                r = asprintf(&s, "%s %u %u %u %s",
+                             k,
+                             rr->srv.priority,
+                             rr->srv.weight,
+                             rr->srv.port,
+                             strna(rr->srv.name));
+                if (r < 0)
+                        return NULL;
+                break;
+
+        case DNS_TYPE_PTR:
+        case DNS_TYPE_NS:
+        case DNS_TYPE_CNAME:
+        case DNS_TYPE_DNAME:
+                s = strjoin(k, " ", rr->ptr.name);
+                if (!s)
+                        return NULL;
+
+                break;
+
+        case DNS_TYPE_HINFO:
+                s = strjoin(k, " ", rr->hinfo.cpu, " ", rr->hinfo.os);
+                if (!s)
+                        return NULL;
+                break;
+
+        case DNS_TYPE_SPF: /* exactly the same as TXT */
+        case DNS_TYPE_TXT:
+                t = format_txt(rr->txt.items);
+                if (!t)
+                        return NULL;
+
+                s = strjoin(k, " ", t);
+                if (!s)
+                        return NULL;
+                break;
+
+        case DNS_TYPE_A: {
+                _cleanup_free_ char *x = NULL;
+
+                r = in_addr_to_string(AF_INET, (const union in_addr_union*) &rr->a.in_addr, &x);
+                if (r < 0)
+                        return NULL;
+
+                s = strjoin(k, " ", x);
+                if (!s)
+                        return NULL;
+                break;
+        }
+
+        case DNS_TYPE_AAAA:
+                r = in_addr_to_string(AF_INET6, (const union in_addr_union*) &rr->aaaa.in6_addr, &t);
+                if (r < 0)
+                        return NULL;
+
+                s = strjoin(k, " ", t);
+                if (!s)
+                        return NULL;
+                break;
+
+        case DNS_TYPE_SOA:
+                r = asprintf(&s, "%s %s %s %u %u %u %u %u",
+                             k,
+                             strna(rr->soa.mname),
+                             strna(rr->soa.rname),
+                             rr->soa.serial,
+                             rr->soa.refresh,
+                             rr->soa.retry,
+                             rr->soa.expire,
+                             rr->soa.minimum);
+                if (r < 0)
+                        return NULL;
+                break;
+
+        case DNS_TYPE_MX:
+                r = asprintf(&s, "%s %u %s",
+                             k,
+                             rr->mx.priority,
+                             rr->mx.exchange);
+                if (r < 0)
+                        return NULL;
+                break;
+
+        case DNS_TYPE_LOC:
+                assert(rr->loc.version == 0);
+
+                t = format_location(rr->loc.latitude,
+                                    rr->loc.longitude,
+                                    rr->loc.altitude,
+                                    rr->loc.size,
+                                    rr->loc.horiz_pre,
+                                    rr->loc.vert_pre);
+                if (!t)
+                        return NULL;
+
+                s = strjoin(k, " ", t);
+                if (!s)
+                        return NULL;
+                break;
+
+        case DNS_TYPE_DS:
+                t = hexmem(rr->ds.digest, rr->ds.digest_size);
+                if (!t)
+                        return NULL;
+
+                r = asprintf(&s, "%s %u %u %u %s",
+                             k,
+                             rr->ds.key_tag,
+                             rr->ds.algorithm,
+                             rr->ds.digest_type,
+                             t);
+                if (r < 0)
+                        return NULL;
+                break;
+
+        case DNS_TYPE_SSHFP:
+                t = hexmem(rr->sshfp.fingerprint, rr->sshfp.fingerprint_size);
+                if (!t)
+                        return NULL;
+
+                r = asprintf(&s, "%s %u %u %s",
+                             k,
+                             rr->sshfp.algorithm,
+                             rr->sshfp.fptype,
+                             t);
+                if (r < 0)
+                        return NULL;
+                break;
+
+        case DNS_TYPE_DNSKEY: {
+                _cleanup_free_ char *alg = NULL;
+                char *ss;
+                int n;
+                uint16_t key_tag;
+
+                key_tag = dnssec_keytag(rr, true);
+
+                r = dnssec_algorithm_to_string_alloc(rr->dnskey.algorithm, &alg);
+                if (r < 0)
+                        return NULL;
+
+                r = asprintf(&s, "%s %u %u %s %n",
+                             k,
+                             rr->dnskey.flags,
+                             rr->dnskey.protocol,
+                             alg,
+                             &n);
+                if (r < 0)
+                        return NULL;
+
+                r = base64_append(&s, n,
+                                  rr->dnskey.key, rr->dnskey.key_size,
+                                  8, columns());
+                if (r < 0)
+                        return NULL;
+
+                r = asprintf(&ss, "%s\n"
+                             "        -- Flags:%s%s%s\n"
+                             "        -- Key tag: %u",
+                             s,
+                             rr->dnskey.flags & DNSKEY_FLAG_SEP ? " SEP" : "",
+                             rr->dnskey.flags & DNSKEY_FLAG_REVOKE ? " REVOKE" : "",
+                             rr->dnskey.flags & DNSKEY_FLAG_ZONE_KEY ? " ZONE_KEY" : "",
+                             key_tag);
+                if (r < 0)
+                        return NULL;
+                free(s);
+                s = ss;
+
+                break;
+        }
+
+        case DNS_TYPE_RRSIG: {
+                _cleanup_free_ char *alg = NULL;
+                char expiration[STRLEN("YYYYMMDDHHmmSS") + 1], inception[STRLEN("YYYYMMDDHHmmSS") + 1];
+                const char *type;
+                int n;
+
+                type = dns_type_to_string(rr->rrsig.type_covered);
+
+                r = dnssec_algorithm_to_string_alloc(rr->rrsig.algorithm, &alg);
+                if (r < 0)
+                        return NULL;
+
+                r = format_timestamp_dns(expiration, sizeof(expiration), rr->rrsig.expiration);
+                if (r < 0)
+                        return NULL;
+
+                r = format_timestamp_dns(inception, sizeof(inception), rr->rrsig.inception);
+                if (r < 0)
+                        return NULL;
+
+                /* TYPE?? follows
+                 * http://tools.ietf.org/html/rfc3597#section-5 */
+
+                r = asprintf(&s, "%s %s%.*u %s %u %u %s %s %u %s %n",
+                             k,
+                             type ?: "TYPE",
+                             type ? 0 : 1, type ? 0u : (unsigned) rr->rrsig.type_covered,
+                             alg,
+                             rr->rrsig.labels,
+                             rr->rrsig.original_ttl,
+                             expiration,
+                             inception,
+                             rr->rrsig.key_tag,
+                             rr->rrsig.signer,
+                             &n);
+                if (r < 0)
+                        return NULL;
+
+                r = base64_append(&s, n,
+                                  rr->rrsig.signature, rr->rrsig.signature_size,
+                                  8, columns());
+                if (r < 0)
+                        return NULL;
+
+                break;
+        }
+
+        case DNS_TYPE_NSEC:
+                t = format_types(rr->nsec.types);
+                if (!t)
+                        return NULL;
+
+                r = asprintf(&s, "%s %s %s",
+                             k,
+                             rr->nsec.next_domain_name,
+                             t);
+                if (r < 0)
+                        return NULL;
+                break;
+
+        case DNS_TYPE_NSEC3: {
+                _cleanup_free_ char *salt = NULL, *hash = NULL;
+
+                if (rr->nsec3.salt_size > 0) {
+                        salt = hexmem(rr->nsec3.salt, rr->nsec3.salt_size);
+                        if (!salt)
+                                return NULL;
+                }
+
+                hash = base32hexmem(rr->nsec3.next_hashed_name, rr->nsec3.next_hashed_name_size, false);
+                if (!hash)
+                        return NULL;
+
+                t = format_types(rr->nsec3.types);
+                if (!t)
+                        return NULL;
+
+                r = asprintf(&s, "%s %"PRIu8" %"PRIu8" %"PRIu16" %s %s %s",
+                             k,
+                             rr->nsec3.algorithm,
+                             rr->nsec3.flags,
+                             rr->nsec3.iterations,
+                             rr->nsec3.salt_size > 0 ? salt : "-",
+                             hash,
+                             t);
+                if (r < 0)
+                        return NULL;
+
+                break;
+        }
+
+        case DNS_TYPE_TLSA: {
+                const char *cert_usage, *selector, *matching_type;
+
+                cert_usage = tlsa_cert_usage_to_string(rr->tlsa.cert_usage);
+                selector = tlsa_selector_to_string(rr->tlsa.selector);
+                matching_type = tlsa_matching_type_to_string(rr->tlsa.matching_type);
+
+                t = hexmem(rr->sshfp.fingerprint, rr->sshfp.fingerprint_size);
+                if (!t)
+                        return NULL;
+
+                r = asprintf(&s,
+                             "%s %u %u %u %s\n"
+                             "        -- Cert. usage: %s\n"
+                             "        -- Selector: %s\n"
+                             "        -- Matching type: %s",
+                             k,
+                             rr->tlsa.cert_usage,
+                             rr->tlsa.selector,
+                             rr->tlsa.matching_type,
+                             t,
+                             cert_usage,
+                             selector,
+                             matching_type);
+                if (r < 0)
+                        return NULL;
+
+                break;
+        }
+
+        case DNS_TYPE_CAA: {
+                _cleanup_free_ char *value;
+
+                value = octescape(rr->caa.value, rr->caa.value_size);
+                if (!value)
+                        return NULL;
+
+                r = asprintf(&s, "%s %u %s \"%s\"%s%s%s%.0u",
+                             k,
+                             rr->caa.flags,
+                             rr->caa.tag,
+                             value,
+                             rr->caa.flags ? "\n        -- Flags:" : "",
+                             rr->caa.flags & CAA_FLAG_CRITICAL ? " critical" : "",
+                             rr->caa.flags & ~CAA_FLAG_CRITICAL ? " " : "",
+                             rr->caa.flags & ~CAA_FLAG_CRITICAL);
+                if (r < 0)
+                        return NULL;
+
+                break;
+        }
+
+        case DNS_TYPE_OPENPGPKEY: {
+                int n;
+
+                r = asprintf(&s, "%s %n",
+                             k,
+                             &n);
+                if (r < 0)
+                        return NULL;
+
+                r = base64_append(&s, n,
+                                  rr->generic.data, rr->generic.data_size,
+                                  8, columns());
+                if (r < 0)
+                        return NULL;
+                break;
+        }
+
+        default:
+                t = hexmem(rr->generic.data, rr->generic.data_size);
+                if (!t)
+                        return NULL;
+
+                /* Format as documented in RFC 3597, Section 5 */
+                r = asprintf(&s, "%s \\# %zu %s", k, rr->generic.data_size, t);
+                if (r < 0)
+                        return NULL;
+                break;
+        }
+
+        rr->to_string = s;
+        return s;
+}
+
+ssize_t dns_resource_record_payload(DnsResourceRecord *rr, void **out) {
+        assert(rr);
+        assert(out);
+
+        switch(rr->unparseable ? _DNS_TYPE_INVALID : rr->key->type) {
+        case DNS_TYPE_SRV:
+        case DNS_TYPE_PTR:
+        case DNS_TYPE_NS:
+        case DNS_TYPE_CNAME:
+        case DNS_TYPE_DNAME:
+        case DNS_TYPE_HINFO:
+        case DNS_TYPE_SPF:
+        case DNS_TYPE_TXT:
+        case DNS_TYPE_A:
+        case DNS_TYPE_AAAA:
+        case DNS_TYPE_SOA:
+        case DNS_TYPE_MX:
+        case DNS_TYPE_LOC:
+        case DNS_TYPE_DS:
+        case DNS_TYPE_DNSKEY:
+        case DNS_TYPE_RRSIG:
+        case DNS_TYPE_NSEC:
+        case DNS_TYPE_NSEC3:
+                return -EINVAL;
+
+        case DNS_TYPE_SSHFP:
+                *out = rr->sshfp.fingerprint;
+                return rr->sshfp.fingerprint_size;
+
+        case DNS_TYPE_TLSA:
+                *out = rr->tlsa.data;
+                return rr->tlsa.data_size;
+
+        case DNS_TYPE_OPENPGPKEY:
+        default:
+                *out = rr->generic.data;
+                return rr->generic.data_size;
+        }
+}
+
+int dns_resource_record_to_wire_format(DnsResourceRecord *rr, bool canonical) {
+
+        DnsPacket packet = {
+                .n_ref = 1,
+                .protocol = DNS_PROTOCOL_DNS,
+                .on_stack = true,
+                .refuse_compression = true,
+                .canonical_form = canonical,
+        };
+
+        size_t start, rds;
+        int r;
+
+        assert(rr);
+
+        /* Generates the RR in wire-format, optionally in the
+         * canonical form as discussed in the DNSSEC RFC 4034, Section
+         * 6.2. We allocate a throw-away DnsPacket object on the stack
+         * here, because we need some book-keeping for memory
+         * management, and can reuse the DnsPacket serializer, that
+         * can generate the canonical form, too, but also knows label
+         * compression and suchlike. */
+
+        if (rr->wire_format && rr->wire_format_canonical == canonical)
+                return 0;
+
+        r = dns_packet_append_rr(&packet, rr, 0, &start, &rds);
+        if (r < 0)
+                return r;
+
+        assert(start == 0);
+        assert(packet._data);
+
+        free(rr->wire_format);
+        rr->wire_format = packet._data;
+        rr->wire_format_size = packet.size;
+        rr->wire_format_rdata_offset = rds;
+        rr->wire_format_canonical = canonical;
+
+        packet._data = NULL;
+        dns_packet_unref(&packet);
+
+        return 0;
+}
+
+int dns_resource_record_signer(DnsResourceRecord *rr, const char **ret) {
+        const char *n;
+        int r;
+
+        assert(rr);
+        assert(ret);
+
+        /* Returns the RRset's signer, if it is known. */
+
+        if (rr->n_skip_labels_signer == (unsigned) -1)
+                return -ENODATA;
+
+        n = dns_resource_key_name(rr->key);
+        r = dns_name_skip(n, rr->n_skip_labels_signer, &n);
+        if (r < 0)
+                return r;
+        if (r == 0)
+                return -EINVAL;
+
+        *ret = n;
+        return 0;
+}
+
+int dns_resource_record_source(DnsResourceRecord *rr, const char **ret) {
+        const char *n;
+        int r;
+
+        assert(rr);
+        assert(ret);
+
+        /* Returns the RRset's synthesizing source, if it is known. */
+
+        if (rr->n_skip_labels_source == (unsigned) -1)
+                return -ENODATA;
+
+        n = dns_resource_key_name(rr->key);
+        r = dns_name_skip(n, rr->n_skip_labels_source, &n);
+        if (r < 0)
+                return r;
+        if (r == 0)
+                return -EINVAL;
+
+        *ret = n;
+        return 0;
+}
+
+int dns_resource_record_is_signer(DnsResourceRecord *rr, const char *zone) {
+        const char *signer;
+        int r;
+
+        assert(rr);
+
+        r = dns_resource_record_signer(rr, &signer);
+        if (r < 0)
+                return r;
+
+        return dns_name_equal(zone, signer);
+}
+
+int dns_resource_record_is_synthetic(DnsResourceRecord *rr) {
+        int r;
+
+        assert(rr);
+
+        /* Returns > 0 if the RR is generated from a wildcard, and is not the asterisk name itself */
+
+        if (rr->n_skip_labels_source == (unsigned) -1)
+                return -ENODATA;
+
+        if (rr->n_skip_labels_source == 0)
+                return 0;
+
+        if (rr->n_skip_labels_source > 1)
+                return 1;
+
+        r = dns_name_startswith(dns_resource_key_name(rr->key), "*");
+        if (r < 0)
+                return r;
+
+        return !r;
+}
+
+void dns_resource_record_hash_func(const DnsResourceRecord *rr, struct siphash *state) {
+        assert(rr);
+
+        dns_resource_key_hash_func(rr->key, state);
+
+        switch (rr->unparseable ? _DNS_TYPE_INVALID : rr->key->type) {
+
+        case DNS_TYPE_SRV:
+                siphash24_compress(&rr->srv.priority, sizeof(rr->srv.priority), state);
+                siphash24_compress(&rr->srv.weight, sizeof(rr->srv.weight), state);
+                siphash24_compress(&rr->srv.port, sizeof(rr->srv.port), state);
+                dns_name_hash_func(rr->srv.name, state);
+                break;
+
+        case DNS_TYPE_PTR:
+        case DNS_TYPE_NS:
+        case DNS_TYPE_CNAME:
+        case DNS_TYPE_DNAME:
+                dns_name_hash_func(rr->ptr.name, state);
+                break;
+
+        case DNS_TYPE_HINFO:
+                string_hash_func(rr->hinfo.cpu, state);
+                string_hash_func(rr->hinfo.os, state);
+                break;
+
+        case DNS_TYPE_TXT:
+        case DNS_TYPE_SPF: {
+                DnsTxtItem *j;
+
+                LIST_FOREACH(items, j, rr->txt.items) {
+                        siphash24_compress(j->data, j->length, state);
+
+                        /* Add an extra NUL byte, so that "a" followed by "b" doesn't result in the same hash as "ab"
+                         * followed by "". */
+                        siphash24_compress_byte(0, state);
+                }
+                break;
+        }
+
+        case DNS_TYPE_A:
+                siphash24_compress(&rr->a.in_addr, sizeof(rr->a.in_addr), state);
+                break;
+
+        case DNS_TYPE_AAAA:
+                siphash24_compress(&rr->aaaa.in6_addr, sizeof(rr->aaaa.in6_addr), state);
+                break;
+
+        case DNS_TYPE_SOA:
+                dns_name_hash_func(rr->soa.mname, state);
+                dns_name_hash_func(rr->soa.rname, state);
+                siphash24_compress(&rr->soa.serial, sizeof(rr->soa.serial), state);
+                siphash24_compress(&rr->soa.refresh, sizeof(rr->soa.refresh), state);
+                siphash24_compress(&rr->soa.retry, sizeof(rr->soa.retry), state);
+                siphash24_compress(&rr->soa.expire, sizeof(rr->soa.expire), state);
+                siphash24_compress(&rr->soa.minimum, sizeof(rr->soa.minimum), state);
+                break;
+
+        case DNS_TYPE_MX:
+                siphash24_compress(&rr->mx.priority, sizeof(rr->mx.priority), state);
+                dns_name_hash_func(rr->mx.exchange, state);
+                break;
+
+        case DNS_TYPE_LOC:
+                siphash24_compress(&rr->loc.version, sizeof(rr->loc.version), state);
+                siphash24_compress(&rr->loc.size, sizeof(rr->loc.size), state);
+                siphash24_compress(&rr->loc.horiz_pre, sizeof(rr->loc.horiz_pre), state);
+                siphash24_compress(&rr->loc.vert_pre, sizeof(rr->loc.vert_pre), state);
+                siphash24_compress(&rr->loc.latitude, sizeof(rr->loc.latitude), state);
+                siphash24_compress(&rr->loc.longitude, sizeof(rr->loc.longitude), state);
+                siphash24_compress(&rr->loc.altitude, sizeof(rr->loc.altitude), state);
+                break;
+
+        case DNS_TYPE_SSHFP:
+                siphash24_compress(&rr->sshfp.algorithm, sizeof(rr->sshfp.algorithm), state);
+                siphash24_compress(&rr->sshfp.fptype, sizeof(rr->sshfp.fptype), state);
+                siphash24_compress(rr->sshfp.fingerprint, rr->sshfp.fingerprint_size, state);
+                break;
+
+        case DNS_TYPE_DNSKEY:
+                siphash24_compress(&rr->dnskey.flags, sizeof(rr->dnskey.flags), state);
+                siphash24_compress(&rr->dnskey.protocol, sizeof(rr->dnskey.protocol), state);
+                siphash24_compress(&rr->dnskey.algorithm, sizeof(rr->dnskey.algorithm), state);
+                siphash24_compress(rr->dnskey.key, rr->dnskey.key_size, state);
+                break;
+
+        case DNS_TYPE_RRSIG:
+                siphash24_compress(&rr->rrsig.type_covered, sizeof(rr->rrsig.type_covered), state);
+                siphash24_compress(&rr->rrsig.algorithm, sizeof(rr->rrsig.algorithm), state);
+                siphash24_compress(&rr->rrsig.labels, sizeof(rr->rrsig.labels), state);
+                siphash24_compress(&rr->rrsig.original_ttl, sizeof(rr->rrsig.original_ttl), state);
+                siphash24_compress(&rr->rrsig.expiration, sizeof(rr->rrsig.expiration), state);
+                siphash24_compress(&rr->rrsig.inception, sizeof(rr->rrsig.inception), state);
+                siphash24_compress(&rr->rrsig.key_tag, sizeof(rr->rrsig.key_tag), state);
+                dns_name_hash_func(rr->rrsig.signer, state);
+                siphash24_compress(rr->rrsig.signature, rr->rrsig.signature_size, state);
+                break;
+
+        case DNS_TYPE_NSEC:
+                dns_name_hash_func(rr->nsec.next_domain_name, state);
+                /* FIXME: we leave out the type bitmap here. Hash
+                 * would be better if we'd take it into account
+                 * too. */
+                break;
+
+        case DNS_TYPE_DS:
+                siphash24_compress(&rr->ds.key_tag, sizeof(rr->ds.key_tag), state);
+                siphash24_compress(&rr->ds.algorithm, sizeof(rr->ds.algorithm), state);
+                siphash24_compress(&rr->ds.digest_type, sizeof(rr->ds.digest_type), state);
+                siphash24_compress(rr->ds.digest, rr->ds.digest_size, state);
+                break;
+
+        case DNS_TYPE_NSEC3:
+                siphash24_compress(&rr->nsec3.algorithm, sizeof(rr->nsec3.algorithm), state);
+                siphash24_compress(&rr->nsec3.flags, sizeof(rr->nsec3.flags), state);
+                siphash24_compress(&rr->nsec3.iterations, sizeof(rr->nsec3.iterations), state);
+                siphash24_compress(rr->nsec3.salt, rr->nsec3.salt_size, state);
+                siphash24_compress(rr->nsec3.next_hashed_name, rr->nsec3.next_hashed_name_size, state);
+                /* FIXME: We leave the bitmaps out */
+                break;
+
+        case DNS_TYPE_TLSA:
+                siphash24_compress(&rr->tlsa.cert_usage, sizeof(rr->tlsa.cert_usage), state);
+                siphash24_compress(&rr->tlsa.selector, sizeof(rr->tlsa.selector), state);
+                siphash24_compress(&rr->tlsa.matching_type, sizeof(rr->tlsa.matching_type), state);
+                siphash24_compress(rr->tlsa.data, rr->tlsa.data_size, state);
+                break;
+
+        case DNS_TYPE_CAA:
+                siphash24_compress(&rr->caa.flags, sizeof(rr->caa.flags), state);
+                string_hash_func(rr->caa.tag, state);
+                siphash24_compress(rr->caa.value, rr->caa.value_size, state);
+                break;
+
+        case DNS_TYPE_OPENPGPKEY:
+        default:
+                siphash24_compress(rr->generic.data, rr->generic.data_size, state);
+                break;
+        }
+}
+
+static int dns_resource_record_compare_func(const DnsResourceRecord *x, const DnsResourceRecord *y) {
+        int r;
+
+        r = dns_resource_key_compare_func(x->key, y->key);
+        if (r != 0)
+                return r;
+
+        if (dns_resource_record_equal(x, y))
+                return 0;
+
+        /* We still use CMP() here, even though don't implement proper
+         * ordering, since the hashtable doesn't need ordering anyway. */
+        return CMP(x, y);
+}
+
+DEFINE_HASH_OPS(dns_resource_record_hash_ops, DnsResourceRecord, dns_resource_record_hash_func, dns_resource_record_compare_func);
+
+DnsResourceRecord *dns_resource_record_copy(DnsResourceRecord *rr) {
+        _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *copy = NULL;
+        DnsResourceRecord *t;
+
+        assert(rr);
+
+        copy = dns_resource_record_new(rr->key);
+        if (!copy)
+                return NULL;
+
+        copy->ttl = rr->ttl;
+        copy->expiry = rr->expiry;
+        copy->n_skip_labels_signer = rr->n_skip_labels_signer;
+        copy->n_skip_labels_source = rr->n_skip_labels_source;
+        copy->unparseable = rr->unparseable;
+
+        switch (rr->unparseable ? _DNS_TYPE_INVALID : rr->key->type) {
+
+        case DNS_TYPE_SRV:
+                copy->srv.priority = rr->srv.priority;
+                copy->srv.weight = rr->srv.weight;
+                copy->srv.port = rr->srv.port;
+                copy->srv.name = strdup(rr->srv.name);
+                if (!copy->srv.name)
+                        return NULL;
+                break;
+
+        case DNS_TYPE_PTR:
+        case DNS_TYPE_NS:
+        case DNS_TYPE_CNAME:
+        case DNS_TYPE_DNAME:
+                copy->ptr.name = strdup(rr->ptr.name);
+                if (!copy->ptr.name)
+                        return NULL;
+                break;
+
+        case DNS_TYPE_HINFO:
+                copy->hinfo.cpu = strdup(rr->hinfo.cpu);
+                if (!copy->hinfo.cpu)
+                        return NULL;
+
+                copy->hinfo.os = strdup(rr->hinfo.os);
+                if (!copy->hinfo.os)
+                        return NULL;
+                break;
+
+        case DNS_TYPE_TXT:
+        case DNS_TYPE_SPF:
+                copy->txt.items = dns_txt_item_copy(rr->txt.items);
+                if (!copy->txt.items)
+                        return NULL;
+                break;
+
+        case DNS_TYPE_A:
+                copy->a = rr->a;
+                break;
+
+        case DNS_TYPE_AAAA:
+                copy->aaaa = rr->aaaa;
+                break;
+
+        case DNS_TYPE_SOA:
+                copy->soa.mname = strdup(rr->soa.mname);
+                if (!copy->soa.mname)
+                        return NULL;
+                copy->soa.rname = strdup(rr->soa.rname);
+                if (!copy->soa.rname)
+                        return NULL;
+                copy->soa.serial = rr->soa.serial;
+                copy->soa.refresh = rr->soa.refresh;
+                copy->soa.retry = rr->soa.retry;
+                copy->soa.expire = rr->soa.expire;
+                copy->soa.minimum = rr->soa.minimum;
+                break;
+
+        case DNS_TYPE_MX:
+                copy->mx.priority = rr->mx.priority;
+                copy->mx.exchange = strdup(rr->mx.exchange);
+                if (!copy->mx.exchange)
+                        return NULL;
+                break;
+
+        case DNS_TYPE_LOC:
+                copy->loc = rr->loc;
+                break;
+
+        case DNS_TYPE_SSHFP:
+                copy->sshfp.algorithm = rr->sshfp.algorithm;
+                copy->sshfp.fptype = rr->sshfp.fptype;
+                copy->sshfp.fingerprint = memdup(rr->sshfp.fingerprint, rr->sshfp.fingerprint_size);
+                if (!copy->sshfp.fingerprint)
+                        return NULL;
+                copy->sshfp.fingerprint_size = rr->sshfp.fingerprint_size;
+                break;
+
+        case DNS_TYPE_DNSKEY:
+                copy->dnskey.flags = rr->dnskey.flags;
+                copy->dnskey.protocol = rr->dnskey.protocol;
+                copy->dnskey.algorithm = rr->dnskey.algorithm;
+                copy->dnskey.key = memdup(rr->dnskey.key, rr->dnskey.key_size);
+                if (!copy->dnskey.key)
+                        return NULL;
+                copy->dnskey.key_size = rr->dnskey.key_size;
+                break;
+
+        case DNS_TYPE_RRSIG:
+                copy->rrsig.type_covered = rr->rrsig.type_covered;
+                copy->rrsig.algorithm = rr->rrsig.algorithm;
+                copy->rrsig.labels = rr->rrsig.labels;
+                copy->rrsig.original_ttl = rr->rrsig.original_ttl;
+                copy->rrsig.expiration = rr->rrsig.expiration;
+                copy->rrsig.inception = rr->rrsig.inception;
+                copy->rrsig.key_tag = rr->rrsig.key_tag;
+                copy->rrsig.signer = strdup(rr->rrsig.signer);
+                if (!copy->rrsig.signer)
+                        return NULL;
+                copy->rrsig.signature = memdup(rr->rrsig.signature, rr->rrsig.signature_size);
+                if (!copy->rrsig.signature)
+                        return NULL;
+                copy->rrsig.signature_size = rr->rrsig.signature_size;
+                break;
+
+        case DNS_TYPE_NSEC:
+                copy->nsec.next_domain_name = strdup(rr->nsec.next_domain_name);
+                if (!copy->nsec.next_domain_name)
+                        return NULL;
+                copy->nsec.types = bitmap_copy(rr->nsec.types);
+                if (!copy->nsec.types)
+                        return NULL;
+                break;
+
+        case DNS_TYPE_DS:
+                copy->ds.key_tag = rr->ds.key_tag;
+                copy->ds.algorithm = rr->ds.algorithm;
+                copy->ds.digest_type = rr->ds.digest_type;
+                copy->ds.digest = memdup(rr->ds.digest, rr->ds.digest_size);
+                if (!copy->ds.digest)
+                        return NULL;
+                copy->ds.digest_size = rr->ds.digest_size;
+                break;
+
+        case DNS_TYPE_NSEC3:
+                copy->nsec3.algorithm = rr->nsec3.algorithm;
+                copy->nsec3.flags = rr->nsec3.flags;
+                copy->nsec3.iterations = rr->nsec3.iterations;
+                copy->nsec3.salt = memdup(rr->nsec3.salt, rr->nsec3.salt_size);
+                if (!copy->nsec3.salt)
+                        return NULL;
+                copy->nsec3.salt_size = rr->nsec3.salt_size;
+                copy->nsec3.next_hashed_name = memdup(rr->nsec3.next_hashed_name, rr->nsec3.next_hashed_name_size);
+                if (!copy->nsec3.next_hashed_name_size)
+                        return NULL;
+                copy->nsec3.next_hashed_name_size = rr->nsec3.next_hashed_name_size;
+                copy->nsec3.types = bitmap_copy(rr->nsec3.types);
+                if (!copy->nsec3.types)
+                        return NULL;
+                break;
+
+        case DNS_TYPE_TLSA:
+                copy->tlsa.cert_usage = rr->tlsa.cert_usage;
+                copy->tlsa.selector = rr->tlsa.selector;
+                copy->tlsa.matching_type = rr->tlsa.matching_type;
+                copy->tlsa.data = memdup(rr->tlsa.data, rr->tlsa.data_size);
+                if (!copy->tlsa.data)
+                        return NULL;
+                copy->tlsa.data_size = rr->tlsa.data_size;
+                break;
+
+        case DNS_TYPE_CAA:
+                copy->caa.flags = rr->caa.flags;
+                copy->caa.tag = strdup(rr->caa.tag);
+                if (!copy->caa.tag)
+                        return NULL;
+                copy->caa.value = memdup(rr->caa.value, rr->caa.value_size);
+                if (!copy->caa.value)
+                        return NULL;
+                copy->caa.value_size = rr->caa.value_size;
+                break;
+
+        case DNS_TYPE_OPT:
+        default:
+                copy->generic.data = memdup(rr->generic.data, rr->generic.data_size);
+                if (!copy->generic.data)
+                        return NULL;
+                copy->generic.data_size = rr->generic.data_size;
+                break;
+        }
+
+        t = TAKE_PTR(copy);
+
+        return t;
+}
+
+int dns_resource_record_clamp_ttl(DnsResourceRecord **rr, uint32_t max_ttl) {
+        DnsResourceRecord *old_rr, *new_rr;
+        uint32_t new_ttl;
+
+        assert(rr);
+        old_rr = *rr;
+
+        if (old_rr->key->type == DNS_TYPE_OPT)
+                return -EINVAL;
+
+        new_ttl = MIN(old_rr->ttl, max_ttl);
+        if (new_ttl == old_rr->ttl)
+                return 0;
+
+        if (old_rr->n_ref == 1) {
+                /* Patch in place */
+                old_rr->ttl = new_ttl;
+                return 1;
+        }
+
+        new_rr = dns_resource_record_copy(old_rr);
+        if (!new_rr)
+                return -ENOMEM;
+
+        new_rr->ttl = new_ttl;
+
+        dns_resource_record_unref(*rr);
+        *rr = new_rr;
+
+        return 1;
+}
+
+DnsTxtItem *dns_txt_item_free_all(DnsTxtItem *i) {
+        DnsTxtItem *n;
+
+        if (!i)
+                return NULL;
+
+        n = i->items_next;
+
+        free(i);
+        return dns_txt_item_free_all(n);
+}
+
+bool dns_txt_item_equal(DnsTxtItem *a, DnsTxtItem *b) {
+
+        if (a == b)
+                return true;
+
+        if (!a != !b)
+                return false;
+
+        if (!a)
+                return true;
+
+        if (a->length != b->length)
+                return false;
+
+        if (memcmp(a->data, b->data, a->length) != 0)
+                return false;
+
+        return dns_txt_item_equal(a->items_next, b->items_next);
+}
+
+DnsTxtItem *dns_txt_item_copy(DnsTxtItem *first) {
+        DnsTxtItem *i, *copy = NULL, *end = NULL;
+
+        LIST_FOREACH(items, i, first) {
+                DnsTxtItem *j;
+
+                j = memdup(i, offsetof(DnsTxtItem, data) + i->length + 1);
+                if (!j) {
+                        dns_txt_item_free_all(copy);
+                        return NULL;
+                }
+
+                LIST_INSERT_AFTER(items, copy, end, j);
+                end = j;
+        }
+
+        return copy;
+}
+
+int dns_txt_item_new_empty(DnsTxtItem **ret) {
+        DnsTxtItem *i;
+
+        /* RFC 6763, section 6.1 suggests to treat
+         * empty TXT RRs as equivalent to a TXT record
+         * with a single empty string. */
+
+        i = malloc0(offsetof(DnsTxtItem, data) + 1); /* for safety reasons we add an extra NUL byte */
+        if (!i)
+                return -ENOMEM;
+
+        *ret = i;
+
+        return 0;
+}
+
+static const char* const dnssec_algorithm_table[_DNSSEC_ALGORITHM_MAX_DEFINED] = {
+        /* Mnemonics as listed on https://www.iana.org/assignments/dns-sec-alg-numbers/dns-sec-alg-numbers.xhtml */
+        [DNSSEC_ALGORITHM_RSAMD5]             = "RSAMD5",
+        [DNSSEC_ALGORITHM_DH]                 = "DH",
+        [DNSSEC_ALGORITHM_DSA]                = "DSA",
+        [DNSSEC_ALGORITHM_ECC]                = "ECC",
+        [DNSSEC_ALGORITHM_RSASHA1]            = "RSASHA1",
+        [DNSSEC_ALGORITHM_DSA_NSEC3_SHA1]     = "DSA-NSEC3-SHA1",
+        [DNSSEC_ALGORITHM_RSASHA1_NSEC3_SHA1] = "RSASHA1-NSEC3-SHA1",
+        [DNSSEC_ALGORITHM_RSASHA256]          = "RSASHA256",
+        [DNSSEC_ALGORITHM_RSASHA512]          = "RSASHA512",
+        [DNSSEC_ALGORITHM_ECC_GOST]           = "ECC-GOST",
+        [DNSSEC_ALGORITHM_ECDSAP256SHA256]    = "ECDSAP256SHA256",
+        [DNSSEC_ALGORITHM_ECDSAP384SHA384]    = "ECDSAP384SHA384",
+        [DNSSEC_ALGORITHM_ED25519]            = "ED25519",
+        [DNSSEC_ALGORITHM_ED448]              = "ED448",
+        [DNSSEC_ALGORITHM_INDIRECT]           = "INDIRECT",
+        [DNSSEC_ALGORITHM_PRIVATEDNS]         = "PRIVATEDNS",
+        [DNSSEC_ALGORITHM_PRIVATEOID]         = "PRIVATEOID",
+};
+DEFINE_STRING_TABLE_LOOKUP_WITH_FALLBACK(dnssec_algorithm, int, 255);
+
+static const char* const dnssec_digest_table[_DNSSEC_DIGEST_MAX_DEFINED] = {
+        /* Names as listed on https://www.iana.org/assignments/ds-rr-types/ds-rr-types.xhtml */
+        [DNSSEC_DIGEST_SHA1] = "SHA-1",
+        [DNSSEC_DIGEST_SHA256] = "SHA-256",
+        [DNSSEC_DIGEST_GOST_R_34_11_94] = "GOST_R_34.11-94",
+        [DNSSEC_DIGEST_SHA384] = "SHA-384",
+};
+DEFINE_STRING_TABLE_LOOKUP_WITH_FALLBACK(dnssec_digest, int, 255);