diff --git a/src/mslookup/mdns.c b/src/mslookup/mdns.c
new file mode 100644
index 0000000..4742a7c
--- /dev/null
+++ b/src/mslookup/mdns.c
@@ -0,0 +1,425 @@
+/* mslookup specific functions for encoding and decoding mslookup queries/results into mDNS packets, using the high
+ * level functions from mdns_msg.c and mdns_record.c to build the request/answer messages. */
+
+/* Copyright 2019 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
+ *
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <osmocom/hlr/logging.h>
+#include <osmocom/core/msgb.h>
+#include <osmocom/mslookup/mslookup.h>
+#include <osmocom/mslookup/mdns_msg.h>
+#include <osmocom/mslookup/mdns_rfc.h>
+#include <errno.h>
+#include <inttypes.h>
+
+static struct msgb *osmo_mdns_msgb_alloc(const char *label)
+{
+	return msgb_alloc(1024, label);
+}
+
+/*! Combine the mslookup query service, ID and ID type into a domain string.
+ * \param[in] domain_suffix  is appended to each domain in the queries to avoid colliding with the top-level domains
+ *                           administrated by IANA. Example: "mdns.osmocom.org"
+ * \returns allocated buffer with the resulting domain (i.e. "sip.voice.123.msisdn.mdns.osmocom.org") on success,
+ * 	    NULL on failure.
+ */
+static char *domain_from_query(void *ctx, const struct osmo_mslookup_query *query, const char *domain_suffix)
+{
+	const char *id;
+
+	/* Get id from query */
+	switch (query->id.type) {
+		case OSMO_MSLOOKUP_ID_IMSI:
+			id = query->id.imsi;
+			break;
+		case OSMO_MSLOOKUP_ID_MSISDN:
+			id = query->id.msisdn;
+			break;
+		default:
+			LOGP(DMSLOOKUP, LOGL_ERROR, "can't encode mslookup query id type %i", query->id.type);
+			return NULL;
+	}
+
+	return talloc_asprintf(ctx, "%s.%s.%s.%s", query->service, id, osmo_mslookup_id_type_name(query->id.type),
+			       domain_suffix);
+}
+
+/*! Split up query service, ID and ID type from a domain string into a mslookup query.
+ * \param[in] domain  with domain_suffix, e.g. "sip.voice.123.msisdn.mdns.osmocom.org"
+ * \param[in] domain_suffix  is appended to each domain in the queries to avoid colliding with the top-level domains
+ *                           administrated by IANA. It is not part of the resulting struct osmo_mslookup_query, so we
+ *                           remove it in this function. Example: "mdns.osmocom.org"
+ */
+int query_from_domain(struct osmo_mslookup_query *query, const char *domain, const char *domain_suffix)
+{
+	int domain_len = strlen(domain) - strlen(domain_suffix) - 1;
+	char domain_buf[OSMO_MDNS_RFC_MAX_NAME_LEN];
+
+	if (domain_len <= 0 || domain_len >= sizeof(domain_buf))
+		return -EINVAL;
+
+	if (domain[domain_len] != '.' || strcmp(domain + domain_len + 1, domain_suffix) != 0)
+		return -EINVAL;
+
+	memcpy(domain_buf, domain, domain_len);
+	domain_buf[domain_len] = '\0';
+	return osmo_mslookup_query_init_from_domain_str(query, domain_buf);
+}
+
+/*! Encode a mslookup query into a mDNS packet.
+ * \param[in] domain_suffix  is appended to each domain in the queries to avoid colliding with the top-level domains
+ *                           administrated by IANA. Example: "mdns.osmocom.org"
+ * \returns msgb, or NULL on error.
+ */
+struct msgb *osmo_mdns_query_encode(void *ctx, uint16_t packet_id, const struct osmo_mslookup_query *query,
+				    const char *domain_suffix)
+{
+	struct osmo_mdns_msg_request req = {0};
+	struct msgb *msg = osmo_mdns_msgb_alloc(__func__);
+
+	req.id = packet_id;
+	req.type = OSMO_MDNS_RFC_RECORD_TYPE_ALL;
+	req.domain = domain_from_query(ctx, query, domain_suffix);
+	if (!req.domain)
+		goto error;
+	if (osmo_mdns_msg_request_encode(ctx, msg, &req))
+		goto error;
+	talloc_free(req.domain);
+	return msg;
+error:
+	msgb_free(msg);
+	talloc_free(req.domain);
+	return NULL;
+}
+
+/*! Decode a mDNS request packet into a mslookup query.
+ * \param[out] packet_id  the result must be sent with the same packet_id.
+ * \param[in] domain_suffix  is appended to each domain in the queries to avoid colliding with the top-level domains
+ *                           administrated by IANA. Example: "mdns.osmocom.org"
+ * \returns allocated mslookup query on success, NULL on error.
+ */
+struct osmo_mslookup_query *osmo_mdns_query_decode(void *ctx, const uint8_t *data, size_t data_len,
+						   uint16_t *packet_id, const char *domain_suffix)
+{
+	struct osmo_mdns_msg_request *req = NULL;
+	struct osmo_mslookup_query *query = NULL;
+
+	req = osmo_mdns_msg_request_decode(ctx, data, data_len);
+	if (!req)
+		return NULL;
+
+	query = talloc_zero(ctx, struct osmo_mslookup_query);
+	OSMO_ASSERT(query);
+	if (query_from_domain(query, req->domain, domain_suffix) < 0)
+		goto error_free;
+
+	*packet_id = req->id;
+	talloc_free(req);
+	return query;
+error_free:
+	talloc_free(req);
+	talloc_free(query);
+	return NULL;
+}
+
+/*! Parse sockaddr_str from mDNS record, so the mslookup result can be filled with it.
+ * \param[out] sockaddr_str resulting IPv4 or IPv6 sockaddr_str.
+ * \param[in] rec  single record of the abstracted list of mDNS records
+ * \returns 0 on success, -EINVAL on error.
+ */
+static int sockaddr_str_from_mdns_record(struct osmo_sockaddr_str *sockaddr_str, struct osmo_mdns_record *rec)
+{
+	switch (rec->type) {
+	case OSMO_MDNS_RFC_RECORD_TYPE_A:
+		if (rec->length != 4) {
+			LOGP(DMSLOOKUP, LOGL_ERROR, "unexpected length of A record\n");
+			return -EINVAL;
+		}
+		osmo_sockaddr_str_from_32(sockaddr_str, *(uint32_t *)rec->data, 0);
+		break;
+	case OSMO_MDNS_RFC_RECORD_TYPE_AAAA:
+		if (rec->length != 16) {
+			LOGP(DMSLOOKUP, LOGL_ERROR, "unexpected length of AAAA record\n");
+			return -EINVAL;
+		}
+		osmo_sockaddr_str_from_in6_addr(sockaddr_str, (struct in6_addr*)rec->data, 0);
+		break;
+	default:
+		LOGP(DMSLOOKUP, LOGL_ERROR, "unexpected record type\n");
+		return -EINVAL;
+	}
+	return 0;
+}
+
+/*! Encode a successful mslookup result, along with the original query and packet_id into one mDNS answer packet.
+ *
+ * The records in the packet are ordered as follows:
+ * 1) "age", ip_v4/v6, "port" (only IPv4 or IPv6 present) or
+ * 2) "age", ip_v4, "port", ip_v6, "port" (both IPv4 and v6 present).
+ * "age" and "port" are TXT records, ip_v4 is an A record, ip_v6 is an AAAA record.
+ *
+ * \param[in] packet_id  as received in osmo_mdns_query_decode().
+ * \param[in] query  the original query, so we can send the domain back in the answer (i.e. "sip.voice.1234.msisdn").
+ * \param[in] result  holds the age, IPs and ports of the queried service.
+ * \param[in] domain_suffix  is appended to each domain in the queries to avoid colliding with the top-level domains
+ *                           administrated by IANA. Example: "mdns.osmocom.org"
+ * \returns msg on success, NULL on error.
+ */
+struct msgb *osmo_mdns_result_encode(void *ctx, uint16_t packet_id, const struct osmo_mslookup_query *query,
+				     const struct osmo_mslookup_result *result, const char *domain_suffix)
+{
+	struct osmo_mdns_msg_answer ans = {};
+	struct osmo_mdns_record *rec_age = NULL;
+	struct osmo_mdns_record rec_ip_v4 = {0};
+	struct osmo_mdns_record rec_ip_v6 = {0};
+	struct osmo_mdns_record *rec_ip_v4_port = NULL;
+	struct osmo_mdns_record *rec_ip_v6_port = NULL;
+	struct in_addr rec_ip_v4_in;
+	struct in6_addr rec_ip_v6_in;
+	struct msgb *msg = osmo_mdns_msgb_alloc(__func__);
+	char buf[256];
+
+	ctx = talloc_named(ctx, 0, "osmo_mdns_result_encode");
+
+	/* Prepare answer (ans) */
+	ans.domain = domain_from_query(ctx, query, domain_suffix);
+	if (!ans.domain)
+		goto error;
+	ans.id = packet_id;
+	INIT_LLIST_HEAD(&ans.records);
+
+	/* Record for age */
+	rec_age = osmo_mdns_record_txt_keyval_encode(ctx, "age", "%"PRIu32, result->age);
+	OSMO_ASSERT(rec_age);
+	llist_add_tail(&rec_age->list, &ans.records);
+
+	/* Records for IPv4 */
+	if (osmo_sockaddr_str_is_set(&result->host_v4)) {
+		if (osmo_sockaddr_str_to_in_addr(&result->host_v4, &rec_ip_v4_in) < 0) {
+			LOGP(DMSLOOKUP, LOGL_ERROR, "failed to encode ipv4: %s\n",
+			     osmo_mslookup_result_name_b(buf, sizeof(buf), query, result));
+			goto error;
+		}
+		rec_ip_v4.type = OSMO_MDNS_RFC_RECORD_TYPE_A;
+		rec_ip_v4.data = (uint8_t *)&rec_ip_v4_in;
+		rec_ip_v4.length = sizeof(rec_ip_v4_in);
+		llist_add_tail(&rec_ip_v4.list, &ans.records);
+
+		rec_ip_v4_port = osmo_mdns_record_txt_keyval_encode(ctx, "port", "%"PRIu16, result->host_v4.port);
+		OSMO_ASSERT(rec_ip_v4_port);
+		llist_add_tail(&rec_ip_v4_port->list, &ans.records);
+	}
+
+	/* Records for IPv6 */
+	if (osmo_sockaddr_str_is_set(&result->host_v6)) {
+		if (osmo_sockaddr_str_to_in6_addr(&result->host_v6, &rec_ip_v6_in) < 0) {
+			LOGP(DMSLOOKUP, LOGL_ERROR, "failed to encode ipv6: %s\n",
+			     osmo_mslookup_result_name_b(buf, sizeof(buf), query, result));
+			goto error;
+		}
+		rec_ip_v6.type = OSMO_MDNS_RFC_RECORD_TYPE_AAAA;
+		rec_ip_v6.data = (uint8_t *)&rec_ip_v6_in;
+		rec_ip_v6.length = sizeof(rec_ip_v6_in);
+		llist_add_tail(&rec_ip_v6.list, &ans.records);
+
+		rec_ip_v6_port = osmo_mdns_record_txt_keyval_encode(ctx, "port", "%"PRIu16, result->host_v6.port);
+		OSMO_ASSERT(rec_ip_v6_port);
+		llist_add_tail(&rec_ip_v6_port->list, &ans.records);
+	}
+
+	if (osmo_mdns_msg_answer_encode(ctx, msg, &ans)) {
+		LOGP(DMSLOOKUP, LOGL_ERROR, "failed to encode mDNS answer: %s\n",
+		     osmo_mslookup_result_name_b(buf, sizeof(buf), query, result));
+		goto error;
+	}
+	talloc_free(ctx);
+	return msg;
+error:
+	msgb_free(msg);
+	talloc_free(ctx);
+	return NULL;
+}
+
+static int decode_uint32_t(const char *str, uint32_t *val)
+{
+	long long int lld;
+	char *endptr = NULL;
+	*val = 0;
+	errno = 0;
+	lld = strtoll(str, &endptr, 10);
+	if (errno || !endptr || *endptr)
+		return -EINVAL;
+	if (lld < 0 || lld > UINT32_MAX)
+		return -EINVAL;
+	*val = lld;
+	return 0;
+}
+
+static int decode_port(const char *str, uint16_t *port)
+{
+	uint32_t val;
+	if (decode_uint32_t(str, &val))
+		return -EINVAL;
+	if (val > 65535)
+		return -EINVAL;
+	*port = val;
+	return 0;
+}
+
+/*! Read expected mDNS records into mslookup result.
+ *
+ * The records in the packet must be ordered as follows:
+ * 1) "age", ip_v4/v6, "port" (only IPv4 or IPv6 present) or
+ * 2) "age", ip_v4, "port", ip_v6, "port" (both IPv4 and v6 present).
+ * "age" and "port" are TXT records, ip_v4 is an A record, ip_v6 is an AAAA record.
+ *
+ * \param[out] result  holds the age, IPs and ports of the queried service.
+ * \param[in] ans  abstracted mDNS answer with a list of resource records.
+ * \returns 0 on success, -EINVAL on error.
+ */
+int osmo_mdns_result_from_answer(struct osmo_mslookup_result *result, const struct osmo_mdns_msg_answer *ans)
+{
+	struct osmo_mdns_record *rec;
+	char txt_key[64];
+	char txt_value[64];
+	bool found_age = false;
+	bool found_ip_v4 = false;
+	bool found_ip_v6 = false;
+	struct osmo_sockaddr_str *expect_port_for = NULL;
+
+	*result = (struct osmo_mslookup_result){};
+
+	result->rc = OSMO_MSLOOKUP_RC_NONE;
+
+	llist_for_each_entry(rec, &ans->records, list) {
+		switch (rec->type) {
+			case OSMO_MDNS_RFC_RECORD_TYPE_A:
+				if (expect_port_for) {
+					LOGP(DMSLOOKUP, LOGL_ERROR,
+					     "'A' record found, but still expecting a 'port' value first\n");
+					return -EINVAL;
+				}
+				if (found_ip_v4) {
+					LOGP(DMSLOOKUP, LOGL_ERROR, "'A' record found twice in mDNS answer\n");
+					return -EINVAL;
+				}
+				found_ip_v4 = true;
+				expect_port_for = &result->host_v4;
+				if (sockaddr_str_from_mdns_record(expect_port_for, rec)) {
+					LOGP(DMSLOOKUP, LOGL_ERROR, "'A' record with invalid address data\n");
+					return -EINVAL;
+				}
+				break;
+			case OSMO_MDNS_RFC_RECORD_TYPE_AAAA:
+				if (expect_port_for) {
+					LOGP(DMSLOOKUP, LOGL_ERROR,
+					     "'AAAA' record found, but still expecting a 'port' value first\n");
+					return -EINVAL;
+				}
+				if (found_ip_v6) {
+					LOGP(DMSLOOKUP, LOGL_ERROR, "'AAAA' record found twice in mDNS answer\n");
+					return -EINVAL;
+				}
+				found_ip_v6 = true;
+				expect_port_for = &result->host_v6;
+				if (sockaddr_str_from_mdns_record(expect_port_for, rec) != 0) {
+					LOGP(DMSLOOKUP, LOGL_ERROR, "'AAAA' record with invalid address data\n");
+					return -EINVAL;
+				}
+				break;
+			case OSMO_MDNS_RFC_RECORD_TYPE_TXT:
+				if (osmo_mdns_record_txt_keyval_decode(rec, txt_key, sizeof(txt_key),
+								       txt_value, sizeof(txt_value)) != 0) {
+					LOGP(DMSLOOKUP, LOGL_ERROR, "failed to decode txt record\n");
+					return -EINVAL;
+				}
+				if (strcmp(txt_key, "age") == 0) {
+					if (found_age) {
+						LOGP(DMSLOOKUP, LOGL_ERROR, "duplicate 'TXT' record for 'age'\n");
+						return -EINVAL;
+					}
+					found_age = true;
+					if (decode_uint32_t(txt_value, &result->age)) {
+						LOGP(DMSLOOKUP, LOGL_ERROR,
+						     "'TXT' record: invalid 'age' value ('age=%s')\n", txt_value);
+						return -EINVAL;
+					}
+				} else if (strcmp(txt_key, "port") == 0) {
+					if (!expect_port_for) {
+						LOGP(DMSLOOKUP, LOGL_ERROR,
+						     "'TXT' record for 'port' without previous 'A' or 'AAAA' record\n");
+						return -EINVAL;
+					}
+					if (decode_port(txt_value, &expect_port_for->port)) {
+						LOGP(DMSLOOKUP, LOGL_ERROR,
+						     "'TXT' record: invalid 'port' value ('port=%s')\n", txt_value);
+						return -EINVAL;
+					}
+					expect_port_for = NULL;
+				} else {
+					LOGP(DMSLOOKUP, LOGL_ERROR, "unexpected key '%s' in TXT record\n", txt_key);
+					return -EINVAL;
+				}
+				break;
+			default:
+				LOGP(DMSLOOKUP, LOGL_ERROR, "unexpected record type\n");
+				return -EINVAL;
+		}
+	}
+
+	/* Check if everything was found */
+	if (!found_age || !(found_ip_v4 || found_ip_v6) || expect_port_for) {
+		LOGP(DMSLOOKUP, LOGL_ERROR, "missing resource records in mDNS answer\n");
+		return -EINVAL;
+	}
+
+	result->rc = OSMO_MSLOOKUP_RC_RESULT;
+	return 0;
+}
+
+/*! Decode a mDNS answer packet into a mslookup result, query and packet_id.
+ * \param[out] packet_id  same ID as sent in the request packet.
+ * \param[out] query  the original query (service, ID, ID type).
+ * \param[out] result  holds the age, IPs and ports of the queried service.
+ * \param[in] domain_suffix  is appended to each domain in the queries to avoid colliding with the top-level domains
+ *                           administrated by IANA. Example: "mdns.osmocom.org"
+ * \returns 0 on success, -EINVAL on error.
+ */
+int osmo_mdns_result_decode(void *ctx, const uint8_t *data, size_t data_len, uint16_t *packet_id,
+			    struct osmo_mslookup_query *query, struct osmo_mslookup_result *result,
+			    const char *domain_suffix)
+{
+	int rc = -EINVAL;
+	struct osmo_mdns_msg_answer *ans;
+	ans = osmo_mdns_msg_answer_decode(ctx, data, data_len);
+	if (!ans)
+		goto exit_free;
+
+	if (query_from_domain(query, ans->domain, domain_suffix) < 0)
+		goto exit_free;
+
+	if (osmo_mdns_result_from_answer(result, ans) < 0)
+		goto exit_free;
+
+	*packet_id = ans->id;
+	rc = 0;
+
+exit_free:
+	talloc_free(ans);
+	return rc;
+}