+int dns_packet_append_rr(DnsPacket *p, const DnsResourceRecord *rr, size_t *start) {
+ size_t saved_size, rdlength_offset, end, rdlength;
+ int r;
+
+ assert(p);
+ assert(rr);
+
+ saved_size = p->size;
+
+ r = dns_packet_append_key(p, rr->key, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint32(p, rr->ttl, NULL);
+ if (r < 0)
+ goto fail;
+
+ /* Initially we write 0 here */
+ r = dns_packet_append_uint16(p, 0, &rdlength_offset);
+ if (r < 0)
+ goto fail;
+
+ switch (rr->unparseable ? _DNS_TYPE_INVALID : rr->key->type) {
+
+ case DNS_TYPE_SRV:
+ r = dns_packet_append_uint16(p, rr->srv.priority, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint16(p, rr->srv.weight, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint16(p, rr->srv.port, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_name(p, rr->srv.name, true, NULL);
+ break;
+
+ case DNS_TYPE_PTR:
+ case DNS_TYPE_NS:
+ case DNS_TYPE_CNAME:
+ case DNS_TYPE_DNAME:
+ r = dns_packet_append_name(p, rr->ptr.name, true, NULL);
+ break;
+
+ case DNS_TYPE_HINFO:
+ r = dns_packet_append_string(p, rr->hinfo.cpu, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_string(p, rr->hinfo.os, NULL);
+ break;
+
+ case DNS_TYPE_SPF: /* exactly the same as TXT */
+ case DNS_TYPE_TXT: {
+ char **s;
+
+ STRV_FOREACH(s, rr->txt.strings) {
+ r = dns_packet_append_string(p, *s, NULL);
+ if (r < 0)
+ goto fail;
+ }
+
+ r = 0;
+ break;
+ }
+
+ case DNS_TYPE_A:
+ r = dns_packet_append_blob(p, &rr->a.in_addr, sizeof(struct in_addr), NULL);
+ break;
+
+ case DNS_TYPE_AAAA:
+ r = dns_packet_append_blob(p, &rr->aaaa.in6_addr, sizeof(struct in6_addr), NULL);
+ break;
+
+ case DNS_TYPE_SOA:
+ r = dns_packet_append_name(p, rr->soa.mname, true, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_name(p, rr->soa.rname, true, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint32(p, rr->soa.serial, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint32(p, rr->soa.refresh, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint32(p, rr->soa.retry, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint32(p, rr->soa.expire, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint32(p, rr->soa.minimum, NULL);
+ break;
+
+ case DNS_TYPE_MX:
+ r = dns_packet_append_uint16(p, rr->mx.priority, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_name(p, rr->mx.exchange, true, NULL);
+ break;
+
+ case DNS_TYPE_LOC:
+ r = dns_packet_append_uint8(p, rr->loc.version, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint8(p, rr->loc.size, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint8(p, rr->loc.horiz_pre, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint8(p, rr->loc.vert_pre, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint32(p, rr->loc.latitude, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint32(p, rr->loc.longitude, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint32(p, rr->loc.altitude, NULL);
+ break;
+
+ case DNS_TYPE_SSHFP:
+ r = dns_packet_append_uint8(p, rr->sshfp.algorithm, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint8(p, rr->sshfp.fptype, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_blob(p, rr->sshfp.key, rr->sshfp.key_size, NULL);
+ break;
+
+ case DNS_TYPE_DNSKEY:
+ r = dns_packet_append_uint16(p, dnskey_to_flags(rr), NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint8(p, 3u, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint8(p, rr->dnskey.algorithm, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_blob(p, rr->dnskey.key, rr->dnskey.key_size, NULL);
+ break;
+
+ case DNS_TYPE_RRSIG:
+ r = dns_packet_append_uint16(p, rr->rrsig.type_covered, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint8(p, rr->rrsig.algorithm, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint8(p, rr->rrsig.labels, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint32(p, rr->rrsig.original_ttl, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint32(p, rr->rrsig.expiration, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint32(p, rr->rrsig.inception, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint8(p, rr->rrsig.key_tag, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_name(p, rr->rrsig.signer, false, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_blob(p, rr->rrsig.signature, rr->rrsig.signature_size, NULL);
+ break;
+
+ case _DNS_TYPE_INVALID: /* unparseable */
+ default:
+
+ r = dns_packet_append_blob(p, rr->generic.data, rr->generic.size, NULL);
+ break;
+ }
+ if (r < 0)
+ goto fail;
+
+ /* Let's calculate the actual data size and update the field */
+ rdlength = p->size - rdlength_offset - sizeof(uint16_t);
+ if (rdlength > 0xFFFF) {
+ r = ENOSPC;
+ goto fail;
+ }
+
+ end = p->size;
+ p->size = rdlength_offset;
+ r = dns_packet_append_uint16(p, rdlength, NULL);
+ if (r < 0)
+ goto fail;
+ p->size = end;
+
+ if (start)
+ *start = saved_size;
+
+ return 0;
+
+fail:
+ dns_packet_truncate(p, saved_size);
+ return r;
+}
+
+