+GNUNET_DNSPARSER_free_packet (struct GNUNET_DNSPARSER_Packet *p);
+
+
+/**
+ * Given a DNS packet @a p, generate the corresponding UDP payload.
+ * Note that we do not attempt to pack the strings with pointers
+ * as this would complicate the code and this is about being
+ * simple and secure, not fast, fancy and broken like bind.
+ *
+ * @param p packet to pack
+ * @param max maximum allowed size for the resulting UDP payload
+ * @param buf set to a buffer with the packed message
+ * @param buf_length set to the length of @a buf
+ * @return #GNUNET_SYSERR if @a p is invalid
+ * #GNUNET_NO if @a p was truncated (but there is still a result in @a buf)
+ * #GNUNET_OK if @a p was packed completely into @a buf
+ */
+int
+GNUNET_DNSPARSER_pack (const struct GNUNET_DNSPARSER_Packet *p,
+ uint16_t max,
+ char **buf,
+ size_t *buf_length);
+
+/* ***************** low-level packing API ******************** */
+
+/**
+ * Add a DNS name to the UDP packet at the given location, converting
+ * the name to IDNA notation as necessary.
+ *
+ * @param dst where to write the name (UDP packet)
+ * @param dst_len number of bytes in @a dst
+ * @param off pointer to offset where to write the name (increment by bytes used)
+ * must not be changed if there is an error
+ * @param name name to write
+ * @return #GNUNET_SYSERR if @a name is invalid
+ * #GNUNET_NO if @a name did not fit
+ * #GNUNET_OK if @a name was added to @a dst
+ */
+int
+GNUNET_DNSPARSER_builder_add_name (char *dst,
+ size_t dst_len,
+ size_t *off,
+ const char *name);
+
+
+/**
+ * Add a DNS query to the UDP packet at the given location.
+ *
+ * @param dst where to write the query
+ * @param dst_len number of bytes in @a dst
+ * @param off pointer to offset where to write the query (increment by bytes used)
+ * must not be changed if there is an error
+ * @param query query to write
+ * @return #GNUNET_SYSERR if @a query is invalid
+ * #GNUNET_NO if @a query did not fit
+ * #GNUNET_OK if @a query was added to @a dst
+ */
+int
+GNUNET_DNSPARSER_builder_add_query (char *dst,
+ size_t dst_len,
+ size_t *off,
+ const struct GNUNET_DNSPARSER_Query *query);
+
+
+/**
+ * Add an MX record to the UDP packet at the given location.
+ *
+ * @param dst where to write the mx record
+ * @param dst_len number of bytes in @a dst
+ * @param off pointer to offset where to write the mx information (increment by bytes used);
+ * can also change if there was an error
+ * @param mx mx information to write
+ * @return #GNUNET_SYSERR if @a mx is invalid
+ * #GNUNET_NO if @a mx did not fit
+ * #GNUNET_OK if @a mx was added to @a dst
+ */
+int
+GNUNET_DNSPARSER_builder_add_mx (char *dst,
+ size_t dst_len,
+ size_t *off,
+ const struct GNUNET_DNSPARSER_MxRecord *mx);
+
+
+/**
+ * Add an SOA record to the UDP packet at the given location.
+ *
+ * @param dst where to write the SOA record
+ * @param dst_len number of bytes in @a dst
+ * @param off pointer to offset where to write the SOA information (increment by bytes used)
+ * can also change if there was an error
+ * @param soa SOA information to write
+ * @return #GNUNET_SYSERR if @a soa is invalid
+ * #GNUNET_NO if @a soa did not fit
+ * #GNUNET_OK if @a soa was added to @a dst
+ */
+int
+GNUNET_DNSPARSER_builder_add_soa (char *dst,
+ size_t dst_len,
+ size_t *off,
+ const struct GNUNET_DNSPARSER_SoaRecord *soa);
+
+
+/**
+ * Add CERT record to the UDP packet at the given location.
+ *
+ * @param dst where to write the CERT record
+ * @param dst_len number of bytes in @a dst
+ * @param off pointer to offset where to write the CERT information (increment by bytes used)
+ * can also change if there was an error
+ * @param cert CERT information to write
+ * @return #GNUNET_SYSERR if @a soa is invalid
+ * #GNUNET_NO if @a soa did not fit
+ * #GNUNET_OK if @a soa was added to @a dst
+ */
+int
+GNUNET_DNSPARSER_builder_add_cert (char *dst,
+ size_t dst_len,
+ size_t *off,
+ const struct GNUNET_DNSPARSER_CertRecord *cert);
+
+
+/**
+ * Add an SRV record to the UDP packet at the given location.
+ *
+ * @param dst where to write the SRV record
+ * @param dst_len number of bytes in @a dst
+ * @param off pointer to offset where to write the SRV information (increment by bytes used)
+ * can also change if there was an error
+ * @param srv SRV information to write
+ * @return #GNUNET_SYSERR if @a srv is invalid
+ * #GNUNET_NO if @a srv did not fit
+ * #GNUNET_OK if @a srv was added to @a dst
+ */
+int
+GNUNET_DNSPARSER_builder_add_srv (char *dst,
+ size_t dst_len,
+ size_t *off,
+ const struct GNUNET_DNSPARSER_SrvRecord *srv);
+
+/* ***************** low-level parsing API ******************** */
+
+/**
+ * Parse a DNS record entry.
+ *
+ * @param udp_payload entire UDP payload
+ * @param udp_payload_length length of @a udp_payload
+ * @param off pointer to the offset of the record to parse in the udp_payload (to be
+ * incremented by the size of the record)
+ * @param r where to write the record information
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR if the record is malformed
+ */
+int
+GNUNET_DNSPARSER_parse_record (const char *udp_payload,
+ size_t udp_payload_length,
+ size_t *off,
+ struct GNUNET_DNSPARSER_Record *r);
+
+
+/**
+ * Parse name inside of a DNS query or record.
+ *
+ * @param udp_payload entire UDP payload
+ * @param udp_payload_length length of @a udp_payload
+ * @param off pointer to the offset of the name to parse in the udp_payload (to be
+ * incremented by the size of the name)
+ * @return name as 0-terminated C string on success, NULL if the payload is malformed
+ */
+char *
+GNUNET_DNSPARSER_parse_name (const char *udp_payload,
+ size_t udp_payload_length,
+ size_t *off);
+
+
+/**
+ * Parse a DNS query entry.
+ *
+ * @param udp_payload entire UDP payload
+ * @param udp_payload_length length of @a udp_payload
+ * @param off pointer to the offset of the query to parse in the udp_payload (to be
+ * incremented by the size of the query)
+ * @param q where to write the query information
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR if the query is malformed
+ */
+int
+GNUNET_DNSPARSER_parse_query (const char *udp_payload,
+ size_t udp_payload_length,
+ size_t *off,
+ struct GNUNET_DNSPARSER_Query *q);
+
+
+/**
+ * Parse a DNS SOA record.
+ *
+ * @param udp_payload reference to UDP packet
+ * @param udp_payload_length length of @a udp_payload
+ * @param off pointer to the offset of the query to parse in the SOA record (to be
+ * incremented by the size of the record), unchanged on error
+ * @return the parsed SOA record, NULL on error
+ */
+struct GNUNET_DNSPARSER_SoaRecord *
+GNUNET_DNSPARSER_parse_soa (const char *udp_payload,
+ size_t udp_payload_length,
+ size_t *off);
+
+
+/**
+ * Parse a DNS CERT record.
+ *
+ * @param udp_payload reference to UDP packet
+ * @param udp_payload_length length of @a udp_payload
+ * @param off pointer to the offset of the query to parse in the CERT record (to be
+ * incremented by the size of the record), unchanged on error
+ * @return the parsed CERT record, NULL on error
+ */
+struct GNUNET_DNSPARSER_CertRecord *
+GNUNET_DNSPARSER_parse_cert (const char *udp_payload,
+ size_t udp_payload_length,
+ size_t *off);
+
+
+/**
+ * Parse a DNS MX record.
+ *
+ * @param udp_payload reference to UDP packet
+ * @param udp_payload_length length of @a udp_payload
+ * @param off pointer to the offset of the query to parse in the MX record (to be
+ * incremented by the size of the record), unchanged on error
+ * @return the parsed MX record, NULL on error
+ */
+struct GNUNET_DNSPARSER_MxRecord *
+GNUNET_DNSPARSER_parse_mx (const char *udp_payload,
+ size_t udp_payload_length,
+ size_t *off);
+
+
+/**
+ * Parse a DNS SRV record.
+ *
+ * @param udp_payload reference to UDP packet
+ * @param udp_payload_length length of @a udp_payload
+ * @param off pointer to the offset of the query to parse in the SRV record (to be
+ * incremented by the size of the record), unchanged on error
+ * @return the parsed SRV record, NULL on error
+ */
+struct GNUNET_DNSPARSER_SrvRecord *
+GNUNET_DNSPARSER_parse_srv (const char *udp_payload,
+ size_t udp_payload_length,
+ size_t *off);
+
+/* ***************** low-level deallocation API ******************** */
+
+/**
+ * Free the given DNS record.
+ *
+ * @param r record to free
+ */
+void
+GNUNET_DNSPARSER_free_record (struct GNUNET_DNSPARSER_Record *r);
+
+
+/**
+ * Free MX information record.
+ *
+ * @param mx record to free
+ */
+void
+GNUNET_DNSPARSER_free_mx (struct GNUNET_DNSPARSER_MxRecord *mx);
+
+
+/**
+ * Free SRV information record.
+ *
+ * @param srv record to free
+ */
+void
+GNUNET_DNSPARSER_free_srv (struct GNUNET_DNSPARSER_SrvRecord *srv);
+
+
+/**
+ * Free SOA information record.
+ *
+ * @param soa record to free
+ */
+void
+GNUNET_DNSPARSER_free_soa (struct GNUNET_DNSPARSER_SoaRecord *soa);
+
+
+/**
+ * Free CERT information record.
+ *
+ * @param cert record to free
+ */
+void
+GNUNET_DNSPARSER_free_cert (struct GNUNET_DNSPARSER_CertRecord *cert);
+
+
+/**
+ * Convert a block of binary data to HEX.
+ *
+ * @param data binary data to convert
+ * @param data_size number of bytes in @a data
+ * @return HEX string (lower case)
+ */
+char *
+GNUNET_DNSPARSER_bin_to_hex (const void *data,
+ size_t data_size);
+
+
+/**
+ * Convert a HEX string to block of binary data.
+ *
+ * @param hex HEX string to convert (may contain mixed case)
+ * @param data where to write result, must be
+ * at least `strlen(hex)/2` bytes long
+ * @return number of bytes written to data
+ */
+size_t
+GNUNET_DNSPARSER_hex_to_bin (const char *hex,
+ void *data);
+