rdata.c

/*
 * rdata.c -- RDATA conversion functions.
 *
 * Copyright (c) 2001-2006, NLnet Labs. All rights reserved.
 *
 * See LICENSE for the license.
 *
 */

#include "config.h"

#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <ctype.h>
#include <netdb.h>
#include <stdlib.h>
#include <string.h>
#include <inttypes.h>
#ifdef HAVE_STRINGS_H
#include <strings.h>
#endif

#include "rdata.h"
#include "zonec.h"
#include "query.h"
#include "dname.h"

/* Taken from RFC 4398, section 2.1.  */
lookup_table_type dns_certificate_types[] = {
/*	0		Reserved */
	{ 1, "PKIX" },	/* X.509 as per PKIX */
	{ 2, "SPKI" },	/* SPKI cert */
	{ 3, "PGP" },	/* OpenPGP packet */
	{ 4, "IPKIX" },	/* The URL of an X.509 data object */
	{ 5, "ISPKI" },	/* The URL of an SPKI certificate */
	{ 6, "IPGP" },	/* The fingerprint and URL of an OpenPGP packet */
	{ 7, "ACPKIX" },	/* Attribute Certificate */
	{ 8, "IACPKIX" },	/* The URL of an Attribute Certificate */
	{ 253, "URI" },	/* URI private */
	{ 254, "OID" },	/* OID private */
/*	255 		Reserved */
/* 	256-65279	Available for IANA assignment */
/*	65280-65534	Experimental */
/*	65535		Reserved */
	{ 0, NULL }
};

/* Taken from RFC 2535, section 7.  */
lookup_table_type dns_algorithms[] = {
	{ 1, "RSAMD5" },	/* RFC 2537 */
	{ 2, "DH" },		/* RFC 2539 */
	{ 3, "DSA" },		/* RFC 2536 */
	{ 4, "ECC" },
	{ 5, "RSASHA1" },	/* RFC 3110 */
	{ 6, "DSA-NSEC3-SHA1" },	/* RFC 5155 */
	{ 7, "RSASHA1-NSEC3-SHA1" },	/* RFC 5155 */
	{ 8, "RSASHA256" },		/* RFC 5702 */
	{ 10, "RSASHA512" },		/* RFC 5702 */
	{ 12, "ECC-GOST" },		/* RFC 5933 */
	{ 13, "ECDSAP256SHA256" },	/* RFC 6605 */
	{ 14, "ECDSAP384SHA384" },	/* RFC 6605 */
	{ 15, "ED25519" },		/* RFC 8080 */
	{ 16, "ED448" },		/* RFC 8080 */
	{ 252, "INDIRECT" },
	{ 253, "PRIVATEDNS" },
	{ 254, "PRIVATEOID" },
	{ 0, NULL }
};

/* Print svcparam key without a value */
static int print_svcparam_no_value(struct buffer *output, uint16_t svcparamkey,
	const uint8_t* data, uint16_t datalen);

/* Print svcparam mandatory */
static int print_svcparam_mandatory(struct buffer *output,
	uint16_t svcparamkey, const uint8_t* data, uint16_t datalen);

/* Print svcparam alpn */
static int print_svcparam_alpn(struct buffer *output,
	uint16_t svcparamkey, const uint8_t* data, uint16_t datalen);

/* Print svcparam port */
static int print_svcparam_port(struct buffer *output,
	uint16_t svcparamkey, const uint8_t* data, uint16_t datalen);

/* Print svcparam ipv4hint */
static int print_svcparam_ipv4hint(struct buffer *output,
	uint16_t svcparamkey, const uint8_t* data, uint16_t datalen);

/* Print svcparam ech */
static int print_svcparam_ech(struct buffer *output,
	uint16_t svcparamkey, const uint8_t* data, uint16_t datalen);

/* Print svcparam ipv6hint */
static int print_svcparam_ipv6hint(struct buffer *output,
	uint16_t svcparamkey, const uint8_t* data, uint16_t datalen);

/* Print svcparam dohpath */
static int print_svcparam_dohpath(struct buffer *output,
	uint16_t svcparamkey, const uint8_t* data, uint16_t datalen);

/* Print svcparam tls-supported-groups */
static int print_svcparam_tls_supported_groups(struct buffer *output,
	uint16_t svcparamkey, const uint8_t* data, uint16_t datalen);

static const nsd_svcparam_descriptor_type svcparams[] = {
	{ SVCB_KEY_MANDATORY, "mandatory", print_svcparam_mandatory },
	{ SVCB_KEY_ALPN, "alpn", print_svcparam_alpn },
	{ SVCB_KEY_NO_DEFAULT_ALPN, "no-default-alpn",
		print_svcparam_no_value },
	{ SVCB_KEY_PORT, "port", print_svcparam_port },
	{ SVCB_KEY_IPV4HINT, "ipv4hint", print_svcparam_ipv4hint },
	{ SVCB_KEY_ECH, "ech", print_svcparam_ech },
	{ SVCB_KEY_IPV6HINT, "ipv6hint", print_svcparam_ipv6hint },
	{ SVCB_KEY_DOHPATH, "dohpath", print_svcparam_dohpath },
	{ SVCB_KEY_OHTTP, "ohttp", print_svcparam_no_value },
	{ SVCB_KEY_TLS_SUPPORTED_GROUPS, "tls-supported-groups",
		print_svcparam_tls_supported_groups },
};

/*
 * Print domain name, as example.com. with escapes.
 * The domain name is wireformat in the rdata. That is a literal dname
 * in the rdata.
 * @param output: the string is output here.
 * @param rdlength: length of rdata.
 * @param rdata: the rdata. The rdata+*offset is where the field is.
 * @param offset: the current position on input. The position is updated to
 *	be incremented with the length of rdata that was used.
 * @return false on failure.
 */
static int
print_name_literal(struct buffer *output, uint16_t rdlength,
	const uint8_t *rdata, uint16_t *offset)
{
	const uint8_t *name, *label, *limit;
	assert(rdlength >= *offset);
	if (rdlength - *offset == 0)
		return 0;

	name = rdata + *offset;
	label = name;
	limit = rdata + rdlength;

	if(*label) {
		do {
			/* space for labellen, label and a next root label. */
			if (label - name > MAXDOMAINLEN-1
				|| *label > MAXLABELLEN
				|| limit - label < 2 + *label)
				return 0;
			label += 1 + *label;
		} while (*label);
	} else {
		/* root domain. */
		/* The label is within the rdlength by the checks at start of
		 * the function. */
	}

	buffer_printf(output, "%s", wiredname2str(name));
	*offset += (label - name) + 1 /* root label */;
	return 1;
}

/*
 * Print domain name, as example.com. with escapes.
 * The domain must be a reference in the rdata. That is a stored pointer
 * to struct domain.
 * @param output: the string is output here.
 * @param rdlength: length of rdata.
 * @param rdata: the rdata. The rdata+*offset is where the field is.
 * @param offset: the current position on input. The position is updated to
 *	be incremented with the length of rdata that was used.
 * @return false on failure.
 */
static int
print_domain(struct buffer *output, uint16_t rdlength, const uint8_t *rdata,
	uint16_t *offset)
{
	const struct dname *dname;
	struct domain *domain;
	if(rdlength - *offset < (uint16_t)sizeof(void*))
		return 0;
	memcpy(&domain, rdata+*offset, sizeof(void*));
	dname = domain_dname(domain);
	buffer_printf(output, "%s", dname_to_string(dname, NULL));
	*offset += sizeof(void*);
	return 1;
}

/* Return length of string or -1 on wireformat error. offset is moved +len. */
static inline int32_t
skip_string(struct buffer* output, uint16_t rdlength, uint16_t* offset)
{
	int32_t length;
	if (rdlength - *offset < 1)
		return -1;
	length = buffer_read_u8(output);
	if (length + 1 > rdlength - *offset)
		return -1;
	buffer_skip(output, length);
	*offset += length + 1;
	return length + 1;
}

/* Return length of strings or -1 on wireformat error. offset is moved +len. */
static inline int32_t
skip_strings(struct buffer* output, uint16_t rdlength, uint16_t* offset)
{
	int32_t olen = 0;
	while(*offset < rdlength) {
		int32_t slen = skip_string(output, rdlength, offset);
		if(slen < 0)
			return slen;
		olen += slen;
	}
	return olen;
}

/*
 * Print string, as "string" with escapes.
 * @param output: the string is output here.
 * @param rdlength: length of rdata.
 * @param rdata: the rdata. The rdata+*offset is where the field is.
 * @param offset: the current position on input. The position is updated to
 *	be incremented with the length of rdata that was used.
 * @return false on failure.
 */
static int
print_string(struct buffer *output, uint16_t rdlength, const uint8_t *rdata,
	uint16_t *offset)
{
	size_t n;
	if(rdlength - *offset < 1)
		return 0;
	n = rdata[*offset];
	if((size_t)rdlength - *offset < 1 + n)
		return 0;
	buffer_printf(output, "\"");
	for (size_t i = 1; i <= n; i++) {
		char ch = (char) rdata[*offset+i];
		if (isprint((unsigned char)ch)) {
			if (ch == '"' || ch == '\\') {
				buffer_printf(output, "\\");
			}
			buffer_printf(output, "%c", ch);
		} else {
			buffer_printf(output, "\\%03u",
				(unsigned) rdata[*offset+i]);
		}
	}
	buffer_printf(output, "\"");
	*offset += 1;
	*offset += n;
	return 1;
}

static int32_t
print_text(struct buffer *output, uint16_t rdlength, const uint8_t *rdata,
	uint16_t *offset)
{
	buffer_printf(output, "\"");
	for (size_t i = *offset; i < rdlength; ++i) {
		char ch = (char) rdata[i];
		if (isprint((unsigned char)ch)) {
			if (ch == '"' || ch == '\\') {
				buffer_printf(output, "\\");
			}
			buffer_printf(output, "%c", ch);
		} else {
			buffer_printf(output, "\\%03u", (unsigned) rdata[i]);
		}
	}
	buffer_printf(output, "\"");
	*offset = rdlength;
	return 1;
}

static int
print_unquoted(buffer_type *output, uint16_t rdlength,
	const uint8_t* rdata, uint16_t* offset)
{
	uint8_t len;
	size_t i;

	if(rdlength - *offset < 1)
		return 0;
	len = rdata[*offset];
	if(((size_t)len) + 1 > (size_t)rdlength - *offset)
		return 0;

	for (i = 1; i <= (size_t)len; ++i) {
		char ch = (char) rdata[*offset + i];
		if (isprint((unsigned char)ch)) {
			if (ch == '"' || ch == '\\' || ch == '(' || ch == ')'
			  || ch == '\'' || isspace((unsigned char)ch)) {
				buffer_printf(output, "\\");
			}
			buffer_printf(output, "%c", ch);
		} else {
			buffer_printf(output, "\\%03u",
				(unsigned) rdata[*offset + i]);
		}
	}
	*offset += 1;
	*offset += len;
	return 1;
}

static int
print_unquoteds(buffer_type *output, uint16_t rdlength,
	const uint8_t* rdata, uint16_t* offset)
{
	while (*offset < rdlength) {
		if(!print_unquoted(output, rdlength, rdata, offset))
			return 0;
		if(*offset < rdlength)
			buffer_printf(output, " ");
	}
	return 1;
}

/*
 * Print IP4 address.
 * @param output: the string is output here.
 * @param rdlength: length of rdata.
 * @param rdata: the rdata. The rdata+*offset is where the field is.
 * @param offset: the current position on input. The position is updated to
 *	be incremented with the length of rdata that was used.
 * @return false on failure.
 */
static int
print_ip4(struct buffer *output, size_t rdlength, const uint8_t *rdata,
	uint16_t *offset)
{
	char str[INET_ADDRSTRLEN + 1];
	assert(rdlength >= *offset);
	if(((size_t)*offset) + 4 > rdlength)
		return 0;
	if(!inet_ntop(AF_INET, rdata + *offset, str, sizeof(str)))
		return 0;
	buffer_printf(output, "%s", str);
	*offset += 4;
	return 1;
}

/*
 * Print IP6 address.
 * @param output: the string is output here.
 * @param rdlength: length of rdata.
 * @param rdata: the rdata. The rdata+*offset is where the field is.
 * @param offset: the current position on input. The position is updated to
 *	be incremented with the length of rdata that was used.
 * @return false on failure.
 */
static int
print_ip6(struct buffer *output, size_t rdlength, const uint8_t *rdata,
	uint16_t *offset)
{
	char str[INET6_ADDRSTRLEN + 1];
	assert(rdlength >= *offset);
	if (rdlength - *offset < 16)
		return 0;
	if (!inet_ntop(AF_INET6, rdata + *offset, str, sizeof(str)))
		return 0;
	buffer_printf(output, "%s", str);
	*offset += 16;
	return 1;
}

/*
 * Print ilnp64 field.
 * @param output: the string is output here.
 * @param rdlength: length of rdata.
 * @param rdata: the rdata. The rdata+*offset is where the field is.
 * @param offset: the current position on input. The position is updated to
 *	be incremented with the length of rdata that was used.
 * @return false on failure.
 */
static int
print_ilnp64(struct buffer *output, uint16_t rdlength, const uint8_t *rdata,
	uint16_t *offset)
{
	uint16_t a1, a2, a3, a4;
	assert(rdlength >= *offset);
	if (rdlength - *offset < 8)
		return 0;
	a1 = read_uint16(rdata + *offset);
	a2 = read_uint16(rdata + *offset + 2);
	a3 = read_uint16(rdata + *offset + 4);
	a4 = read_uint16(rdata + *offset + 6);

	buffer_printf(output, "%.4x:%.4x:%.4x:%.4x", a1, a2, a3, a4);
	*offset += 8;
	return 1;
}

/*
 * Print certificate type.
 * @param output: the string is output here.
 * @param rdlength: length of rdata.
 * @param rdata: the rdata. The rdata+*offset is where the field is.
 * @param offset: the current position on input. The position is updated to
 *	be incremented with the length of rdata that was used.
 * @return false on failure.
 */
static int
print_certificate_type(struct buffer *output, size_t rdlength,
	const uint8_t *rdata, uint16_t *offset)
{
	uint16_t id;
	lookup_table_type* type;
	if (rdlength < *offset || rdlength - *offset < 2)
		return 0;
	id = read_uint16(rdata + *offset);
	type = lookup_by_id(dns_certificate_types, id);
	if (type)
		buffer_printf(output, "%s", type->name);
	else
		buffer_printf(output, "%u", (unsigned) id);
	*offset += 2;
	return 1;
}

/*
 * Print time field.
 * @param output: the string is output here.
 * @param rdlength: length of rdata.
 * @param rdata: the rdata. The rdata+*offset is where the field is.
 * @param offset: the current position on input. The position is updated to
 *	be incremented with the length of rdata that was used.
 * @return false on failure.
 */
static int
print_time(struct buffer *output, uint16_t rdlength, const uint8_t *rdata,
	uint16_t *offset)
{
	time_t time;
	struct tm tmbuf;
	struct tm* tm;
	char buf[15];

	assert(rdlength >= *offset);
	if (rdlength - *offset < 4)
		return 0;
	time = (time_t)read_uint32(rdata + *offset);
	tm = gmtime_r(&time, &tmbuf);
	if (!strftime(buf, sizeof(buf), "%Y%m%d%H%M%S", tm))
		return 0;
	buffer_printf(output, "%s", buf);
	*offset += 4;
	return 1;
}

/*
 * Print base32 output for a b32 field length uint8_t, like for NSEC3.
 * @param output: the string is output here.
 * @param rdlength: length of rdata.
 * @param rdata: the rdata. The rdata+*offset is where the field is.
 * @param offset: the current position on input. The position is updated to
 *	be incremented with the length of rdata that was used.
 * @return false on failure.
 */
static int
print_base32(struct buffer *output, uint16_t rdlength, const uint8_t *rdata,
	uint16_t *offset)
{
	size_t size;
	int length;
	if(rdlength - *offset == 0)
		return 0;
	size = rdata[*offset];
	if (rdlength - ((size_t)*offset) < 1 + size)
		return 0;

	if (size == 0) {
		buffer_write(output, "-", 1);
		*offset += 1;
		return 1;
	}

	buffer_reserve(output, size * 2 + 1);
	length = b32_ntop(rdata + *offset + 1, size,
			  (char *)buffer_current(output), size * 2);
	if (length == -1)
		return 0;
	buffer_skip(output, length);
	*offset += 1 + size;
	return 1;
}

/*
 * Print base64 output for the remainder of rdata.
 * @param output: the string is output here.
 * @param rdlength: length of rdata.
 * @param rdata: the rdata. The rdata+*offset is where the field is.
 * @param offset: the current position on input. The position is updated to
 *	be incremented with the length of rdata that was used.
 * @return false on failure.
 */
static int
print_base64(struct buffer *output, uint16_t rdlength, const uint8_t *rdata,
	uint16_t *offset)
{
	int length;
	size_t size = rdlength - *offset;
	if(size == 0) {
		/* single zero represents empty buffer */
		buffer_write(output, "0", 1);
		return 1;
	}
	buffer_reserve(output, size * 2 + 1);
	length = b64_ntop(rdata + *offset, size,
			  (char *) buffer_current(output), size * 2);
	if (length == -1)
		return 0;
	buffer_skip(output, length);
	*offset += size;
	return 1;
}

static void
buffer_print_hex(buffer_type *output, const uint8_t *data, size_t size)
{
	static const char hexdigits[] = {
		'0', '1', '2', '3', '4', '5', '6', '7',
		'8', '9', 'a', 'b', 'c', 'd', 'e', 'f'
	};
	size_t i;

	buffer_reserve(output, size * 2);
	for (i = 0; i < size; ++i) {
		uint8_t octet = *data++;
		buffer_write_u8(output, hexdigits[octet >> 4]);
		buffer_write_u8(output, hexdigits[octet & 0x0f]);
	}
}

/*
 * Print base16 output for the remainder of rdata, in hex lowercase.
 * @param output: the string is output here.
 * @param rdlength: length of rdata.
 * @param rdata: the rdata. The rdata+*offset is where the field is.
 * @param offset: the current position on input. The position is updated to
 *	be incremented with the length of rdata that was used.
 * @return false on failure.
 */
static int
print_base16(struct buffer *output, uint16_t rdlength, const uint8_t *rdata,
	uint16_t *offset)
{
	size_t size = rdlength - *offset;
	if(size == 0) {
		/* single zero represents empty buffer, such as CDS deletes */
		buffer_write(output, "0", 1);
		return 1;
	} else {
		buffer_print_hex(output, rdata+*offset, size);
	}
	*offset += size;
	return 1;
}

/*
 * Print salt, for NSEC3, in hex lowercase.
 * @param output: the string is output here.
 * @param rdlength: length of rdata.
 * @param rdata: the rdata. The rdata+*offset is where the field is.
 * @param offset: the current position on input. The position is updated to
 *	be incremented with the length of rdata that was used.
 * @return false on failure.
 */
static int
print_salt(struct buffer *output, uint16_t rdlength, const uint8_t *rdata,
	uint16_t *offset)
{
	uint8_t length;
	assert(rdlength >= *offset);
	if (rdlength - *offset == 0)
		return 0;

	length = rdata[*offset];
	if (rdlength - *offset < 1 + length)
		return 0;
	if (!length)
		/* NSEC3 salt hex can be empty */
		buffer_printf(output, "-");
	else
		buffer_print_hex(output, rdata + *offset + 1, length);
	*offset += 1 + (uint16_t)length;
	return 1;
}

/* Return length of nsec type bitmap or -1 on wireformat error. offset is
 * moved +len. rdlength is the length of the rdata, offset is offset in it. */
static inline int32_t
skip_nsec(struct buffer* packet, uint16_t rdlength, uint16_t *offset)
{
	uint16_t length = 0;
	uint8_t last_window = 0;

	while (rdlength - *offset - length > 2) {
		uint8_t window = buffer_read_u8(packet);
		uint8_t blocks = buffer_read_u8(packet);
		if (length > 0 && window <= last_window)
			return -1;
		if (!blocks || blocks > 32)
			return -1;
		if (rdlength - *offset - length < 2 + blocks)
			return -1;
		buffer_skip(packet, blocks);
		length += 2 + blocks;
		last_window = window;
	}

	*offset += length;
	if (rdlength != *offset)
		return -1;

	return length;
}

/*
 * Print nsec type bitmap, for the remainder of rdata.
 * @param output: the string is output here.
 * @param rdlength: length of rdata.
 * @param rdata: the rdata. The rdata+*offset is where the field is.
 * @param offset: the current position on input. The position is updated to
 *	be incremented with the length of rdata that was used.
 * @return false on failure.
 */
static int
print_nsec_bitmap(struct buffer *output, uint16_t rdlength,
	const uint8_t *rdata, uint16_t *offset)
{
	int insert_space = 0;

	rdata += *offset;
	while(rdlength - *offset > 0) {
		uint8_t window, bitmap_size;
		const uint8_t* bitmap;
		int i;

		if(rdlength - *offset < 2)
			return 0;
		window = rdata[0];
		bitmap_size = rdata[1];
		*offset += 2;

		if(rdlength - *offset < bitmap_size)
			return 0;

		bitmap = rdata + 2;
		rdata += 2;
		for(i=0; i<((int)bitmap_size)*8; i++) {
			if (get_bit(bitmap, i)) {
				buffer_printf(output,
					      "%s%s",
					      insert_space ? " " : "",
					      rrtype_to_string(
						      window * 256 + i));
				insert_space = 1;
			}
		}
		rdata += bitmap_size;
		*offset += bitmap_size;
	}
	return 1;
}

/* If an svcparam must have a value */
static int
svcparam_must_have_value(uint16_t svcparamkey)
{
	switch (svcparamkey) {
	case SVCB_KEY_ALPN:
	case SVCB_KEY_PORT:
	case SVCB_KEY_IPV4HINT:
	case SVCB_KEY_IPV6HINT:
	case SVCB_KEY_MANDATORY:
	case SVCB_KEY_DOHPATH:
	case SVCB_KEY_TLS_SUPPORTED_GROUPS:
		return 1;
	default:
		break;
	}
	return 0;
}

/* If an svcparam must not have a value */
static int
svcparam_must_not_have_value(uint16_t svcparamkey)
{
	switch (svcparamkey) {
	case SVCB_KEY_NO_DEFAULT_ALPN:
	case SVCB_KEY_OHTTP:
		return 1;
	default:
		break;
	}
	return 0;
};

/*
 * Skip over the svcparams in the packet. Moves position.
 * @param packet: wire packet, position at rdata fields of svcparams.
 * @param rdlength: remaining rdata length in the packet.
 * @return 0 on wireformat error.
 */
static inline int
skip_svcparams(struct buffer *packet, uint16_t rdlength)
{
	unsigned pos = 0;
	uint16_t key, count;
	while(pos < rdlength) {
		if(pos+4 > (unsigned)rdlength)
			return 0;
		if(!buffer_available(packet, 4))
			return 0;
		key = buffer_read_u16(packet);
		count = buffer_read_u16(packet);
		if(count == 0 && svcparam_must_have_value(key))
			return 0;
		if(count != 0 && svcparam_must_not_have_value(key))
			return 0;
		pos += 4;
		if(pos+count > (unsigned)rdlength)
			return 0;
		if(!buffer_available(packet, count))
			return 0;
		buffer_skip(packet, count);
		pos += count;
	}
	return 1;
}

/*
 * Print svcparamkey name to the buffer, or unknown as key<NUM>.
 * @param output: printed to string.
 * @param svcparamkey: the key to print.
 */
static void
buffer_print_svcparamkey(buffer_type *output, uint16_t svcparamkey)
{
	if (svcparamkey < sizeof(svcparams)/sizeof(svcparams[0]))
		buffer_printf(output, "%s", svcparams[svcparamkey].name);
	else
		buffer_printf(output, "key%" PRIu16, svcparamkey);
}

static int
print_svcparam_no_value(struct buffer *output, uint16_t svcparamkey,
	const uint8_t* ATTR_UNUSED(data), uint16_t ATTR_UNUSED(datalen))
{
	buffer_print_svcparamkey(output, svcparamkey);
	return 1;
}

static int
print_svcparam_mandatory(struct buffer *output, uint16_t svcparamkey,
	const uint8_t* data, uint16_t datalen)
{
	assert(datalen > 0); /* Guaranteed by svcparam_print */

	if (datalen % sizeof(uint16_t))
		return 0; /* wireformat error, val_len must be multiple of shorts */
	buffer_print_svcparamkey(output, svcparamkey);
	buffer_write_u8(output, '=');
	buffer_print_svcparamkey(output, read_uint16(data));
	data += 2;

	while ((datalen -= sizeof(uint16_t))) {
		buffer_write_u8(output, ',');
		buffer_print_svcparamkey(output, read_uint16(data));
		data += 2;
	}

	return 1;
}

static int
print_svcparam_alpn(struct buffer *output, uint16_t svcparamkey,
	const uint8_t* data, uint16_t datalen)
{
	uint8_t *dp = (void *)data;

	assert(datalen > 0); /* Guaranteed by svcparam_print */

	buffer_print_svcparamkey(output, svcparamkey);
	buffer_write_u8(output, '=');
	buffer_write_u8(output, '"');
	while (datalen) {
		uint8_t i, str_len = *dp++;

		if (str_len > --datalen)
			return 0;

		for (i = 0; i < str_len; i++) {
			if (dp[i] == '"' || dp[i] == '\\')
				buffer_printf(output, "\\\\\\%c", dp[i]);

			else if (dp[i] == ',')
				buffer_printf(output, "\\\\%c", dp[i]);

			else if (!isprint(dp[i]))
				buffer_printf(output, "\\%03u", (unsigned) dp[i]);

			else
				buffer_write_u8(output, dp[i]);
		}
		dp += str_len;
		if ((datalen -= str_len))
			buffer_write_u8(output, ',');
	}
	buffer_write_u8(output, '"');
	return 1;
}

static int
print_svcparam_port(struct buffer *output, uint16_t svcparamkey,
	const uint8_t* data, uint16_t datalen)
{
	if (datalen != 2)
		return 0; /* wireformat error, a short is 2 bytes */
	buffer_print_svcparamkey(output, svcparamkey);
	buffer_printf(output, "=%d", (int)read_uint16(data));
	return 1;
}

static int
print_svcparam_ipv4hint(struct buffer *output, uint16_t svcparamkey,
	const uint8_t* data, uint16_t datalen)
{
	char ip_str[INET_ADDRSTRLEN + 1];

	assert(datalen > 0); /* Guaranteed by svcparam_print */

	buffer_print_svcparamkey(output, svcparamkey);
	if ((datalen % IP4ADDRLEN) == 0) {
		if (inet_ntop(AF_INET, data, ip_str, sizeof(ip_str)) == NULL)
			return 0; /* wireformat error, incorrect size or inet family */

		buffer_printf(output, "=%s", ip_str);
		data += IP4ADDRLEN;

		while ((datalen -= IP4ADDRLEN) > 0) {
			if (inet_ntop(AF_INET, data, ip_str, sizeof(ip_str))
				== NULL)
				return 0; /* wireformat error, incorrect size or inet family */

			buffer_printf(output, ",%s", ip_str);
			data += IP4ADDRLEN;
		}
		return 1;
	}
	return 0;
}

static int
print_svcparam_ech(struct buffer *output, uint16_t svcparamkey,
	const uint8_t* data, uint16_t datalen)
{
	int length;

	buffer_print_svcparamkey(output, svcparamkey);
	if(datalen == 0)
		return 1;
	buffer_write_u8(output, '=');

	buffer_reserve(output, datalen * 2 + 1);
	length = b64_ntop(data, datalen, (char*)buffer_current(output),
		datalen * 2);
	if (length > 0) {
		buffer_skip(output, length);
	}

	return length != -1;
}

static int
print_svcparam_ipv6hint(struct buffer *output, uint16_t svcparamkey,
	const uint8_t* data, uint16_t datalen)
{
	char ip_str[INET6_ADDRSTRLEN + 1];

	assert(datalen > 0); /* Guaranteed by svcparam_print */

	buffer_print_svcparamkey(output, svcparamkey);
	if ((datalen % IP6ADDRLEN) == 0) {
		if (inet_ntop(AF_INET6, data, ip_str, sizeof(ip_str)) == NULL)
			return 0; /* wireformat error, incorrect size or inet family */

		buffer_printf(output, "=%s", ip_str);
		data += IP6ADDRLEN;

		while ((datalen -= IP6ADDRLEN) > 0) {
			if (inet_ntop(AF_INET6, data, ip_str, sizeof(ip_str))
				== NULL)
				return 0; /* wireformat error, incorrect size or inet family */

			buffer_printf(output, ",%s", ip_str);
			data += IP6ADDRLEN;
		}
		return 1;
	}
	return 0;
}

static int
print_svcparam_dohpath(struct buffer *output, uint16_t svcparamkey,
	const uint8_t* data, uint16_t datalen)
{
	const uint8_t* dp = data;
	unsigned i;

	buffer_print_svcparamkey(output, svcparamkey);
	buffer_write(output, "=\"", 2);
	for (i = 0; i < datalen; i++) {
		if (dp[i] == '"' || dp[i] == '\\')
			buffer_printf(output, "\\%c", dp[i]);

		else if (!isprint(dp[i]))
			buffer_printf(output, "\\%03u", (unsigned) dp[i]);

		else
			buffer_write_u8(output, dp[i]);
	}
	buffer_write_u8(output, '"');
	return 1;
}

static int
print_svcparam_tls_supported_groups(struct buffer *output,
	uint16_t svcparamkey, const uint8_t* data, uint16_t datalen)
{
	assert(datalen > 0); /* Guaranteed by svcparam_print */

	if ((datalen % sizeof(uint16_t)) == 1)
		return 0; /* A series of uint16_t is an even number of bytes */

	buffer_print_svcparamkey(output, svcparamkey);
	buffer_printf(output, "=%d", (int)read_uint16(data));
	data += 2;
	while ((datalen -= sizeof(uint16_t)) > 0) {
		buffer_printf(output, ",%d", (int)read_uint16(data));
		data += 2;
	}
	return 1;
}

/*
 * Print svcparam.
 * @param output: the string is output here.
 * @param rdlength: length of rdata.
 * @param rdata: the rdata. The rdata+*offset is where the field is.
 * @param offset: the current position on input. The position is updated to
 *	be incremented with the length of rdata that was used.
 * @return false on failure.
 */
static int
print_svcparam(struct buffer *output, uint16_t rdlength, const uint8_t *rdata,
	uint16_t *offset)
{
	uint16_t key, length;
	const uint8_t* dp;
	unsigned i;

	assert(rdlength >= *offset);
	if (rdlength - *offset < 4)
		return 0;

	key = read_uint16(rdata + *offset);
	length = read_uint16(rdata + *offset + 2);

	if (rdlength - *offset < length + 4)
		return 0; /* wireformat error */

	if(length == 0 && svcparam_must_have_value(key))
		return 0;
	if(length != 0 && svcparam_must_not_have_value(key))
		return 0;
	if (key < sizeof(svcparams)/sizeof(svcparams[0])) {
		if(!svcparams[key].print_rdata(output, key, rdata+*offset+4, length))
			return 0;
		*offset += length+4;
		return 1;
	}

	buffer_printf(output, "key%" PRIu16, key);
	if (!length) {
		*offset += 4;
		return 1;
	}

	buffer_write(output, "=\"", 2);
	dp = rdata + *offset + 4;

	for (i = 0; i < length; i++) {
		if (dp[i] == '"' || dp[i] == '\\')
			buffer_printf(output, "\\%c", dp[i]);

		else if (!isprint(dp[i]))
			buffer_printf(output, "\\%03u", (unsigned) dp[i]);

		else
			buffer_write_u8(output, dp[i]);
	}
	buffer_write_u8(output, '"');
	*offset += length + 4;
	return 1;
}

static inline int32_t
read_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	if (buffer_remaining(packet) < rdlength)
		return MALFORMED;
	if (!(*rr = region_alloc(domains->region, sizeof(**rr) + rdlength)))
		return TRUNCATED;
	if(rdlength != 0)
		buffer_read(packet, (*rr)->rdata, rdlength);
	(*rr)->rdlength = rdlength;
	return rdlength;
}

int32_t
read_generic_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	return read_rdata(domains, rdlength, packet, rr);
}

void
write_generic_rdata(struct query *query, const struct rr *rr)
{
	if(rr->rdlength != 0)
		buffer_write(query->packet, rr->rdata, rr->rdlength);
}

int
print_generic_rdata(struct buffer *output, const struct rr *rr)
{
	const nsd_type_descriptor_type* descriptor =
		nsd_type_descriptor(rr->type);
	return print_unknown_rdata_field(output, descriptor, rr);
}

int
lookup_rdata_field_entry(const nsd_type_descriptor_type* descriptor,
	size_t index, const rr_type* rr, uint16_t offset, uint16_t* field_len,
	struct domain** domain)
{
	const nsd_rdata_descriptor_type* field =
		&descriptor->rdata.fields[index];
	if(field->calculate_length) {
		/* Call field length function. */
		int32_t l = field->calculate_length(rr->rdlength, rr->rdata,
			offset, domain);
		if(l < 0)
			return 0;
		*field_len = l;
	} else if(field->length >= 0) {
		*field_len = field->length;
		*domain = NULL;
	} else {
		size_t dlen;
		int32_t flen;
		if(offset > rr->rdlength)
			return 0;
		/* Handle the specialized value cases. */
		switch(field->length) {
		case RDATA_COMPRESSED_DNAME:
		case RDATA_UNCOMPRESSED_DNAME:
			if(rr->rdlength - offset <
				(uint16_t)sizeof(void*))
				return 0;
			*field_len = sizeof(void*);
			memcpy(domain, rr->rdata+offset, sizeof(void*));
			break;
		case RDATA_LITERAL_DNAME:
			dlen = buf_dname_length(rr->rdata+offset,
				rr->rdlength-offset);
			if(dlen == 0)
				return 0;
			*field_len = dlen;
			*domain = NULL;
			break;
		case RDATA_STRING:
		case RDATA_BINARY:
			if(rr->rdlength - offset < 1)
				return 0;
			flen = (rr->rdata+offset)[0];
			*field_len = flen+1;
			*domain = NULL;
			break;
		case RDATA_IPSECGATEWAY:
		case RDATA_AMTRELAY_RELAY:
			return 0; /* Has a callback function. */
		case RDATA_REMAINDER:
			*field_len = rr->rdlength - offset;
			*domain = NULL;
			break;
		default:
			/* Unknown specialized value. */
			return 0;
		}
	}
	if(offset + *field_len > rr->rdlength)
		return 0; /* The field does not fit in the rdata. */
	return 1;
}

int
lookup_rdata_field_entry_uncompressed_wire(
	const nsd_type_descriptor_type* descriptor, size_t index,
	const uint8_t* rdata, uint16_t rdlength, uint16_t offset,
	uint16_t* field_len, struct domain** domain)
{
	const nsd_rdata_descriptor_type* field =
		&descriptor->rdata.fields[index];
	if(field->calculate_length) {
		/* Call field length function. */
		int32_t l = field->calculate_length_uncompressed_wire(rdlength,
			rdata, offset, domain);
		if(l < 0)
			return 0;
		*field_len = l;
	} else if(field->length >= 0) {
		*field_len = field->length;
		*domain = NULL;
	} else {
		size_t dlen;
		int32_t flen;
		if(offset > rdlength)
			return 0;
		/* Handle the specialized value cases. */
		switch(field->length) {
		case RDATA_COMPRESSED_DNAME:
		case RDATA_UNCOMPRESSED_DNAME:
			/* In the case that the field type is of type dname,
			 * since this function deals with uncompressed
			 * wireformat in the rdata buffer, the dname is
			 * going to be there as an uncompressed wireformat
			 * dname, for RDATA_COMPRESSED_DNAME and
			 * RDATA_UNCOMPRESSED_DNAME. */
		case RDATA_LITERAL_DNAME:
			dlen = buf_dname_length(rdata+offset, rdlength-offset);
			if(dlen == 0)
				return 0;
			*field_len = dlen;
			*domain = NULL;
			break;
		case RDATA_STRING:
		case RDATA_BINARY:
			if(rdlength - offset < 1)
				return 0;
			flen = (rdata+offset)[0];
			*field_len = flen+1;
			*domain = NULL;
			break;
		case RDATA_IPSECGATEWAY:
		case RDATA_AMTRELAY_RELAY:
			return 0; /* Has a callback function. */
		case RDATA_REMAINDER:
			*field_len = rdlength - offset;
			*domain = NULL;
			break;
		default:
			/* Unknown specialized value. */
			return 0;
		}
	}
	if(offset + *field_len > rdlength)
		return 0; /* The field does not fit in the rdata. */
	return 1;
}

int32_t
rr_calculate_uncompressed_rdata_length(const rr_type* rr)
{
	size_t i;
	const nsd_type_descriptor_type* descriptor =
		nsd_type_descriptor(rr->type);
	uint16_t offset = 0;
	int32_t result = 0;
	if(!descriptor->has_references)
		return rr->rdlength; /* It does not really validate the
			fields versus the rdlength. */
	for(i=0; i < descriptor->rdata.length; i++) {
		uint16_t field_len;
		struct domain* domain;
		if(rr->rdlength == offset &&
			descriptor->rdata.fields[i].is_optional)
			break; /* There are no more rdata fields. */
		if(!lookup_rdata_field_entry(descriptor, i, rr, offset,
			&field_len, &domain))
			return -1; /* malformed rdata buffer */
		if(domain != NULL) {
			/* Handle RDATA_COMPRESSED_DNAME and
			 * RDATA_UNCOMPRESSED_DNAME fields. */
			const struct dname* dname = domain_dname(domain);
			result += dname->name_size;
		} else {
			result += field_len;
		}
		offset += field_len;
	}
	return result;
}

void
rr_write_uncompressed_rdata(const rr_type* rr, uint8_t* buf, size_t len)
{
	size_t i;
	const nsd_type_descriptor_type* descriptor =
		nsd_type_descriptor(rr->type);
	uint16_t offset = 0; /* The offset in rr->rdatas. */
	size_t pos = 0; /* The position in buf. */
	if(!descriptor->has_references) {
		/* It does not really validate the fields versus the
		 * rdlength. */
		if(rr->rdlength > len)
			return; /* buffer too small */
		memcpy(buf, rr->rdata, rr->rdlength);
		return;
	}
	for(i=0; i < descriptor->rdata.length; i++) {
		uint16_t field_len;
		struct domain* domain;
		if(rr->rdlength == offset &&
			descriptor->rdata.fields[i].is_optional)
			break; /* There are no more rdata fields. */
		if(!lookup_rdata_field_entry(descriptor, i, rr, offset,
			&field_len, &domain))
			return; /* malformed rdata buffer */
		if(domain != NULL) {
			/* Handle RDATA_COMPRESSED_DNAME and
			 * RDATA_UNCOMPRESSED_DNAME fields. */
			const struct dname* dname = domain_dname(domain);
			if(pos + dname->name_size > len)
				return; /* buffer too small */
			memcpy(buf+pos, dname_name(dname), dname->name_size);
			pos += dname->name_size;
		} else {
			if(pos + field_len > len)
				return; /* buffer too small */
			memcpy(buf+pos, rr->rdata+offset, field_len);
			pos += field_len;
		}
		offset += field_len;
	}
}

int print_unknown_rdata_field(buffer_type *output,
	const nsd_type_descriptor_type *descriptor, const rr_type *rr)
{
	size_t i;
	int32_t size;
	uint16_t length = 0;

	if(!descriptor->has_references) {
		/* There are no references to the domain table, the
		 * rdata can be printed literally. */
		buffer_printf(output, "\\# %lu ", (unsigned long)rr->rdlength);
		buffer_print_hex(output, rr->rdata, rr->rdlength);
		return 1;
	}

	size = rr_calculate_uncompressed_rdata_length(rr);
	if(size < 0)
		return 0;
	buffer_printf(output, "\\# %lu ", (unsigned long) size);

	for(i=0; i < descriptor->rdata.length; i++) {
		uint16_t field_len;
		struct domain* domain;
		const uint8_t* to_print;
		size_t to_print_len;
		if(rr->rdlength == length &&
			descriptor->rdata.fields[i].is_optional)
			break; /* There are no more rdata fields. */
		if(!lookup_rdata_field_entry(descriptor, i, rr, length,
			&field_len, &domain))
			return 0; /* malformed rdata buffer */
		if(domain != NULL) {
			/* Handle RDATA_COMPRESSED_DNAME and
			 * RDATA_UNCOMPRESSED_DNAME fields. */
			const struct dname* dname = domain_dname(domain);
			to_print = dname_name(dname);
			to_print_len = dname->name_size;
		} else {
			to_print = rr->rdata+length;
			to_print_len = field_len;
		}
		buffer_print_hex(output, to_print, to_print_len);
		length += field_len;
	}
	return 1;
}

int print_unknown_rdata(buffer_type *output,
	const nsd_type_descriptor_type *descriptor, const rr_type *rr)
{
	buffer_printf(output, "\t");
	return print_unknown_rdata_field(output, descriptor, rr);
}

int32_t
read_compressed_name_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	struct domain *domain;
	struct dname_buffer dname;
	size_t size;
	const size_t mark = buffer_position(packet);

	if (!dname_make_from_packet_buffered(&dname, packet, 1, 1) ||
	    rdlength != buffer_position(packet) - mark)
		return MALFORMED;
	size = sizeof(**rr) + sizeof(void*);
	if (!(*rr = region_alloc(domains->region, size)))
		return TRUNCATED;
	domain = domain_table_insert(domains, (void*)&dname);
	domain->usage++;
	memcpy((*rr)->rdata, &domain, sizeof(void*));
	(*rr)->rdlength = sizeof(void*);
	return rdlength;
}

int32_t
read_uncompressed_name_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	struct domain *domain;
	struct dname_buffer dname;
	size_t size;
	const size_t mark = buffer_position(packet);

	if (!dname_make_from_packet_buffered(&dname, packet,
		1 /* Lenient, allows pointers. */, 1) ||
		rdlength != buffer_position(packet)-mark)
		return MALFORMED;
	size = sizeof(**rr) + sizeof(void*);
	if (!(*rr = region_alloc(domains->region, size)))
		return TRUNCATED;
	domain = domain_table_insert(domains, (void*)&dname);
	domain->usage++;
	memcpy((*rr)->rdata, &domain, sizeof(void*));
	(*rr)->rdlength = sizeof(void*);
	return rdlength;
}

static void
encode_dname(query_type *q, domain_type *domain)
{
	while (domain->parent && query_get_dname_offset(q, domain) == 0) {
		query_put_dname_offset(q, domain, buffer_position(q->packet));
		DEBUG(DEBUG_NAME_COMPRESSION, 2,
		      (LOG_INFO, "dname: %s, number: %lu, offset: %u\n",
		       domain_to_string(domain),
		       (unsigned long) domain->number,
		       query_get_dname_offset(q, domain)));
		buffer_write(q->packet, dname_name(domain_dname(domain)),
			     label_length(dname_name(domain_dname(domain))) + 1U);
		domain = domain->parent;
	}
	if (domain->parent) {
		DEBUG(DEBUG_NAME_COMPRESSION, 2,
		      (LOG_INFO, "dname: %s, number: %lu, pointer: %u\n",
		       domain_to_string(domain),
		       (unsigned long) domain->number,
		       query_get_dname_offset(q, domain)));
		assert(query_get_dname_offset(q, domain) <= MAX_COMPRESSION_OFFSET);
		buffer_write_u16(q->packet,
				 0xc000 | query_get_dname_offset(q, domain));
	} else {
		buffer_write_u8(q->packet, 0);
	}
}

void
write_compressed_name_rdata(struct query *query, const struct rr *rr)
{
	struct domain *domain;
	assert(rr->rdlength == sizeof(void*));
	memcpy(&domain, rr->rdata, sizeof(void*));
	encode_dname(query, domain);
}

void
write_uncompressed_name_rdata(struct query *query, const struct rr *rr)
{
	const struct dname *dname;
	struct domain *domain;
	assert(rr->rdlength >= sizeof(void*));
	memcpy(&domain, rr->rdata, sizeof(void*));
	dname = domain_dname(domain);
	buffer_write(query->packet, dname_name(dname), dname->name_size);
}

int
print_name_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 0;
	assert(rr->rdlength == sizeof(void*));
	/* This prints a reference to a name stored as a pointer. */
	return print_domain(output, rr->rdlength, rr->rdata, &length);
}

int32_t
read_a_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	if (rdlength != 4)
		return MALFORMED;
	return read_rdata(domains, rdlength, packet, rr);
}

int
print_a_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 0;
	assert(rr->rdlength == 4);
	return print_ip4(output, rr->rdlength, rr->rdata, &length);
}

int32_t
read_soa_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	struct domain *primary_domain, *mailbox_domain;
	struct dname_buffer primary, mailbox;
	size_t size;

	/* domain + domain + uint32 + uint32 + uint32 + uint32 + uint32 */
	const size_t mark = buffer_position(packet);
	if (!dname_make_from_packet_buffered(&primary, packet, 1, 1) ||
	    !dname_make_from_packet_buffered(&mailbox, packet, 1, 1) ||
	    rdlength != (buffer_position(packet) - mark) + 20)
		return MALFORMED;

	size = sizeof(**rr) + 2 * sizeof(void*) + 20;
	if (!(*rr = region_alloc(domains->region, size)))
		return TRUNCATED;
	primary_domain = domain_table_insert(domains, (void*)&primary);
	primary_domain->usage++;
	mailbox_domain = domain_table_insert(domains, (void*)&mailbox);
	mailbox_domain->usage++;

	memcpy((*rr)->rdata, &primary_domain, sizeof(void*));
	memcpy((*rr)->rdata + sizeof(void*), &mailbox_domain, sizeof(void*));
	buffer_read(packet, (*rr)->rdata + 2 * sizeof(void*), 20);
	(*rr)->rdlength = 2 * sizeof(void*) + 20;
	return rdlength;
}

void
write_soa_rdata(struct query *query, const struct rr *rr)
{
	struct domain *primary, *mailbox;
	/* domain + domain + uint32 + uint32 + uint32 + uint32 + uint32 */
	assert(rr->rdlength == 2 * sizeof(void*) + 20);
	memcpy(&primary, rr->rdata, sizeof(void*));
	memcpy(&mailbox, rr->rdata + sizeof(void*), sizeof(void*));
	encode_dname(query, primary);
	encode_dname(query, mailbox);
	buffer_write(query->packet, rr->rdata + (2 * sizeof(void*)), 20);
}

int
print_soa_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 0;
	uint32_t serial, refresh, retry, expire, minimum;
	assert(rr->rdlength == 2 * sizeof(void*) + 20);
	if (!print_domain(output, rr->rdlength, rr->rdata, &length))
		return 0;
	buffer_printf(output, " ");
	if (!print_domain(output, rr->rdlength, rr->rdata, &length))
		return 0;

	assert(length == 2 * sizeof(void*));
	serial = read_uint32(rr->rdata + length);
	refresh = read_uint32(rr->rdata + length + 4);
	retry = read_uint32(rr->rdata + length + 8);
	expire = read_uint32(rr->rdata + length + 12);
	minimum = read_uint32(rr->rdata + length + 16);

	buffer_printf(
		output, " %" PRIu32 " %" PRIu32 " %" PRIu32 " %" PRIu32 " %" PRIu32,
		serial, refresh, retry, expire, minimum);
	return 1;
}

int
print_soa_rdata_twoline(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 0;
	uint32_t serial, refresh, retry, expire, minimum;
	assert(rr->rdlength == 2 * sizeof(void*) + 20);
	if (!print_domain(output, rr->rdlength, rr->rdata, &length))
		return 0;
	buffer_printf(output, " ");
	if (!print_domain(output, rr->rdlength, rr->rdata, &length))
		return 0;

	assert(length == 2 * sizeof(void*));
	serial = read_uint32(rr->rdata + length);
	refresh = read_uint32(rr->rdata + length + 4);
	retry = read_uint32(rr->rdata + length + 8);
	expire = read_uint32(rr->rdata + length + 12);
	minimum = read_uint32(rr->rdata + length + 16);

	buffer_printf(
		output, " (\n\t\t%" PRIu32 " %" PRIu32 " %" PRIu32 " %" PRIu32 " %" PRIu32 " )",
		serial, refresh, retry, expire, minimum);
	return 1;
}

int32_t
read_wks_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	if (rdlength < 5)
		return MALFORMED;
	return read_rdata(domains, rdlength, packet, rr);
}

/*
 * Print protocol and service numbers rather than names for Well-Know Services
 * (WKS) RRs. WKS RRs are deprecated, though not technically, and should not
 * be used. The parser supports tcp/udp for protocols and a small subset of
 * services because getprotobyname and/or getservbyname are marked MT-Unsafe
 * and locale. getprotobyname_r and getservbyname_r exist on some platforms,
 * but are still marked locale (meaning the locale object is used without
 * synchonization, which is a problem for a library). Failure to load a zone
 * on a primary server because of an unknown protocol or service name is
 * acceptable as the operator can opt to use the numeric value. Failure to
 * load a zone on a secondary server is problematic because "unsupported"
 * protocols and services might be written. Print the numeric value for
 * maximum compatibility.
 *
 * (see simdzone/generic/wks.h for details).
 */
int
print_wks_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 0;
	uint8_t protocol;
	int bits;
	const uint8_t* bitmap;

	if(rr->rdlength < 5)
		return 0;
	if (!print_ip4(output, rr->rdlength, rr->rdata, &length))
		return 0;

	buffer_printf(output, " ");
	protocol = rr->rdata[4];
	if(protocol == 6)
		buffer_printf(output, "tcp");
	else if(protocol == 17)
		buffer_printf(output, "udp");
	else
		buffer_printf(output, "%" PRIu8, protocol);

	bits = (rr->rdlength - 5) * 8;
	bitmap = rr->rdata + 5;
	for (int service = 0; service < bits; service++) {
		if (get_bit(bitmap, service))
			buffer_printf(output, " %d", service);
	}
	return 1;
}

int32_t
read_hinfo_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	uint16_t length = 0;
	const size_t mark = buffer_position(packet);

	if(!buffer_available(packet, rdlength))
		return MALFORMED;
	if (skip_string(packet, rdlength, &length) < 0
	 || skip_string(packet, rdlength, &length) < 0
	 || rdlength != length)
		return MALFORMED;
	buffer_set_position(packet, mark);
	return read_rdata(domains, rdlength, packet, rr);
}

int
print_hinfo_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 0;
	if (!print_string(output, rr->rdlength, rr->rdata, &length))
		return 0;
	buffer_printf(output, " ");
	if (!print_string(output, rr->rdlength, rr->rdata, &length))
		return 0;
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int32_t
read_minfo_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	struct domain *rmailbx_domain, *emailbx_domain;
	struct dname_buffer rmailbx, emailbx;
	size_t size;
	const size_t mark = buffer_position(packet);

	if (buffer_remaining(packet) < rdlength ||
	    !dname_make_from_packet_buffered(&rmailbx, packet, 1, 1) ||
	    !dname_make_from_packet_buffered(&emailbx, packet, 1, 1) ||
	    rdlength != buffer_position(packet)-mark)
		return MALFORMED;
	size = sizeof(**rr) + 2 * sizeof(void*);
	if (!(*rr = region_alloc(domains->region, size)))
		return TRUNCATED;
	rmailbx_domain = domain_table_insert(domains, (void*)&rmailbx);
	rmailbx_domain->usage++;
	emailbx_domain = domain_table_insert(domains, (void*)&emailbx);
	emailbx_domain->usage++;
	memcpy((*rr)->rdata, &rmailbx_domain, sizeof(void*));
	memcpy((*rr)->rdata + sizeof(void*), &emailbx_domain, sizeof(void*));
	(*rr)->rdlength = 2 * sizeof(void*);
	return rdlength;
}

void
write_minfo_rdata(struct query *query, const struct rr *rr)
{
	struct domain *rmailbx, *emailbx;
	assert(rr->rdlength == 2 * sizeof(void*));
	memcpy(&rmailbx, rr->rdata, sizeof(void*));
	memcpy(&emailbx, rr->rdata + sizeof(void*), sizeof(void*));
	encode_dname(query, rmailbx);
	encode_dname(query, emailbx);
}

int
print_minfo_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 0;
	assert(rr->rdlength == 2 * sizeof(void*));
	if (!print_domain(output, rr->rdlength, rr->rdata, &length))
		return 0;
	buffer_printf(output, " ");
	if (!print_domain(output, rr->rdlength, rr->rdata, &length))
		return 0;
	assert(rr->rdlength == length);
	return 1;
}

int32_t
read_mx_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	struct domain *domain;
	struct dname_buffer exchange;
	size_t size;

	/* short + name */
	const size_t mark = buffer_position(packet);
	if (buffer_remaining(packet) < rdlength || rdlength < 2)
		return MALFORMED;
	buffer_skip(packet, 2);
	if (!dname_make_from_packet_buffered(&exchange, packet, 1, 1))
		return MALFORMED;
	if (rdlength != buffer_position(packet)-mark)
		return MALFORMED;
	size = sizeof(**rr) + 2 + sizeof(void*);
	if (!(*rr = region_alloc(domains->region, size)))
		return -1;
	domain = domain_table_insert(domains, (void*)&exchange);
	domain->usage++;
	buffer_read_at(packet, mark, (*rr)->rdata, 2);
	memcpy((*rr)->rdata + 2, &domain, sizeof(void*));
	(*rr)->rdlength = 2 + sizeof(void*);
	return rdlength;
}

void
write_mx_rdata(struct query *query, const struct rr *rr)
{
	struct domain *domain;
	assert(rr->rdlength == 2 + sizeof(void*));
	memcpy(&domain, rr->rdata + 2, sizeof(void*));
	buffer_write(query->packet, rr->rdata, 2);
	encode_dname(query, domain);
}

int
print_mx_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 2;
	assert(rr->rdlength > length);
	buffer_printf(output, "%" PRIu16 " ", read_uint16(rr->rdata));
	if (!print_domain(output, rr->rdlength, rr->rdata, &length))
		return 0;
	assert(rr->rdlength == length);
	return 1;
}

int32_t
read_txt_rdata(struct domain_table *owners, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	uint16_t length = 0;
	const size_t mark = buffer_position(packet);
	if(!buffer_available(packet, rdlength))
		return MALFORMED;
	if (skip_strings(packet, rdlength, &length) < 0 || rdlength != length)
		return MALFORMED;
	buffer_set_position(packet, mark);
	return read_rdata(owners, rdlength, packet, rr);
}

int
print_txt_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 0;
	if (length < rr->rdlength) {
		if (!print_string(output, rr->rdlength, rr->rdata, &length))
			return 0;
		while (length < rr->rdlength) {
			buffer_printf(output, " ");
			if (!print_string(output, rr->rdlength, rr->rdata,
				&length))
				return 0;
		}
	}
	return 1;
}

int32_t
read_rp_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	struct domain *mbox_domain, *txt_domain;
	struct dname_buffer mbox, txt;
	size_t size;
	const size_t mark = buffer_position(packet);

	if (buffer_remaining(packet) < rdlength ||
	    !dname_make_from_packet_buffered(&mbox, packet, 1 /*lenient*/, 1) ||
	    !dname_make_from_packet_buffered(&txt, packet, 1 /*lenient*/, 1) ||
	    rdlength != buffer_position(packet)-mark)
		return MALFORMED;
	size = sizeof(**rr) + 2 * sizeof(void*);
	if (!(*rr = region_alloc(domains->region, size)))
		return TRUNCATED;
	mbox_domain = domain_table_insert(domains, (void*)&mbox);
	mbox_domain->usage++;
	txt_domain = domain_table_insert(domains, (void*)&txt);
	txt_domain->usage++;
	memcpy((*rr)->rdata, &mbox_domain, sizeof(void*));
	memcpy((*rr)->rdata + sizeof(void*), &txt_domain, sizeof(void*));
	(*rr)->rdlength = 2 * sizeof(void*);
	return rdlength;
}

void
write_rp_rdata(struct query *query, const struct rr *rr)
{
	struct domain *mbox_domain, *txt_domain;
	const struct dname *mbox, *txt;

	assert(rr->rdlength == 2 * sizeof(void*));
	memcpy(&mbox_domain, rr->rdata, sizeof(void*));
	memcpy(&txt_domain, rr->rdata + sizeof(void*), sizeof(void*));
	mbox = domain_dname(mbox_domain);
	txt = domain_dname(txt_domain);
	buffer_write(query->packet, dname_name(mbox), mbox->name_size);
	buffer_write(query->packet, dname_name(txt), txt->name_size);
}

int
print_rp_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 0;
	if(!print_domain(output, rr->rdlength, rr->rdata, &length))
		return 0;
	buffer_printf(output, " ");
	if(!print_domain(output, rr->rdlength, rr->rdata, &length))
		return 0;
	assert(rr->rdlength == length);
	return 1;
}

int32_t
read_afsdb_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	struct domain *domain;
	struct dname_buffer hostname;
	size_t size;
	/* short + uncompressed name */
	const size_t mark = buffer_position(packet);

	if (buffer_remaining(packet) < rdlength || rdlength < 2)
		return MALFORMED;
	buffer_skip(packet, 2);
	if (!dname_make_from_packet_buffered(&hostname, packet,
		1 /*lenient*/, 1) ||
	    rdlength != buffer_position(packet)-mark)
		return MALFORMED;
	size = sizeof(**rr) + 2 + sizeof(void*);
	if (!(*rr = region_alloc(domains->region, size)))
		return TRUNCATED;
	domain = domain_table_insert(domains, (void*)&hostname);
	domain->usage++;
	buffer_read_at(packet, mark, (*rr)->rdata, 2);
	memcpy((*rr)->rdata + 2, &domain, sizeof(void*));
	(*rr)->rdlength = 2 + sizeof(void*);
	return rdlength;
}

void
write_afsdb_rdata(struct query *query, const struct rr *rr)
{
	struct domain *domain;
	const struct dname *dname;

	assert(rr->rdlength == 2 + sizeof(void*));
	memcpy(&domain, rr->rdata + 2, sizeof(void*));
	dname = domain_dname(domain);
	buffer_write(query->packet, rr->rdata, 2);
	buffer_write(query->packet, dname_name(dname), dname->name_size);
}

int
print_afsdb_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t subtype, length=2;
	assert(rr->rdlength == 2 + sizeof(void*));
	subtype = read_uint16(rr->rdata);
	buffer_printf(output, "%" PRIu16 " ", subtype);
	if(!print_domain(output, rr->rdlength, rr->rdata, &length))
		return 0;
	return 1;
}

int32_t
read_x25_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	uint16_t length = 0;
	const size_t mark = buffer_position(packet);
	if(!buffer_available(packet, rdlength))
		return MALFORMED;
	if (skip_string(packet, rdlength, &length) < 0 || rdlength != length)
		return MALFORMED;
	buffer_set_position(packet, mark);
	return read_rdata(domains, rdlength, packet, rr);
}

int
print_x25_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 0;
	if (!print_string(output, rr->rdlength, rr->rdata, &length))
		return 0;
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int32_t
read_isdn_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	uint16_t length = 0;
	const size_t mark = buffer_position(packet);

	if(!buffer_available(packet, rdlength))
		return MALFORMED;
	if (skip_string(packet, rdlength, &length) < 0)
		return MALFORMED;
	if(rdlength > length) {
		/* Optional subaddress field is present. */
		if (skip_string(packet, rdlength, &length) < 0
		 || rdlength != length)
			return MALFORMED;
	}
	buffer_set_position(packet, mark);
	return read_rdata(domains, rdlength, packet, rr);
}

int
print_isdn_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 0;
	if (!print_string(output, rr->rdlength, rr->rdata, &length))
		return 0;
	if(rr->rdlength > length) {
		/* Optional subaddress field is present. */
		buffer_printf(output, " ");
		if (!print_string(output, rr->rdlength, rr->rdata, &length))
			return 0;
	}
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int32_t
read_rt_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	struct domain *domain;
	struct dname_buffer dname;
	size_t size;
	const size_t mark = buffer_position(packet);

	if(!buffer_available(packet, rdlength))
		return MALFORMED;
	if (rdlength < 2)
		return MALFORMED;
	buffer_skip(packet, 2);
	if (!dname_make_from_packet_buffered(&dname, packet, 1 /*lenient*/, 1))
		return MALFORMED;
	if (rdlength != buffer_position(packet)-mark)
		return MALFORMED;
	size = sizeof(**rr) + 2 + sizeof(void*);
	if (!(*rr = region_alloc(domains->region, size)))
		return -1;
	domain = domain_table_insert(domains, (void*)&dname);
	domain->usage++;
	buffer_read_at(packet, mark, (*rr)->rdata, 2);
	memcpy((*rr)->rdata + 2, &domain, sizeof(void*));
	(*rr)->rdlength = 2 + sizeof(void*);
	return rdlength;
}

void
write_rt_rdata(struct query *query, const struct rr *rr)
{
	struct domain *domain;
	const struct dname *dname;

	assert(rr->rdlength == 2 + sizeof(void*));
	memcpy(&domain, rr->rdata + 2, sizeof(void*));
	dname = domain_dname(domain);
	buffer_write(query->packet, rr->rdata, 2);
	buffer_write(query->packet, dname_name(dname), dname->name_size);
}

int
print_nsap_rdata(struct buffer *output, const struct rr *rr)
{
	buffer_printf(output, "0x");
	buffer_print_hex(output, rr->rdata, rr->rdlength);
	return 1;
}

int
print_nsap_ptr_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 0;
	if(!print_unquoted(output, rr->rdlength, rr->rdata, &length))
		return 0;
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int
print_key_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 4;
	if(rr->rdlength < length)
		return 0;
	buffer_printf(
		output, "%" PRIu16 " %" PRIu8 " %" PRIu8 " ",
		read_uint16(rr->rdata), rr->rdata[2], rr->rdata[3]);
	if (!print_base64(output, rr->rdlength, rr->rdata, &length))
		return 0;
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int32_t
read_px_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	struct domain *map822_domain, *mapx400_domain;
	struct dname_buffer map822, mapx400;
	size_t size;
	const size_t mark = buffer_position(packet);

	/* short + uncompressed name + uncompressed name */
	if (buffer_remaining(packet) < rdlength ||
	    rdlength < 2)
		return MALFORMED;
	buffer_skip(packet, 2);
	if(!dname_make_from_packet_buffered(&map822, packet,
		1 /*lenient*/, 1) ||
	   !dname_make_from_packet_buffered(&mapx400, packet,
		1 /*lenient*/, 1) ||
	   rdlength != buffer_position(packet) - mark)
		return MALFORMED;

	size = sizeof(**rr) + 2 + 2*sizeof(void*);
	if (!(*rr = region_alloc(domains->region, size)))
		return TRUNCATED;
	map822_domain = domain_table_insert(domains, (void*)&map822);
	map822_domain->usage++;
	mapx400_domain = domain_table_insert(domains, (void*)&mapx400);
	mapx400_domain->usage++;

	buffer_read_at(packet, mark, (*rr)->rdata, 2);
	memcpy((*rr)->rdata+2, &map822_domain, sizeof(void*));
	memcpy((*rr)->rdata+2+sizeof(void*), &mapx400_domain, sizeof(void*));
	(*rr)->rdlength = 2 + 2*sizeof(void*);
	return rdlength;
}

void
write_px_rdata(struct query *query, const struct rr *rr)
{
	struct domain *map822_domain, *mapx400_domain;
	const struct dname *map822, *mapx400;

	memcpy(&map822_domain, rr->rdata + 2, sizeof(void*));
	memcpy(&mapx400_domain, rr->rdata + 2 + sizeof(void*), sizeof(void*));
	map822 = domain_dname(map822_domain);
	mapx400 = domain_dname(mapx400_domain);
	buffer_write(query->packet, rr->rdata, 2);
	buffer_write(query->packet, dname_name(map822), map822->name_size);
	buffer_write(query->packet, dname_name(mapx400), mapx400->name_size);
}

int
print_px_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 2;
	assert(rr->rdlength > 3);
	buffer_printf(output, "%" PRIu16 " ", read_uint16(rr->rdata));
	if (!print_domain(output, rr->rdlength, rr->rdata, &length))
		return 0;
	buffer_printf(output, " ");
	if (!print_domain(output, rr->rdlength, rr->rdata, &length))
		return 0;
	assert(rr->rdlength == length);
	return 1;
}

int
print_gpos_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 0;
	if(!print_unquoted(output, rr->rdlength, rr->rdata, &length))
		return 0;
	buffer_printf(output, " ");
	if(!print_unquoted(output, rr->rdlength, rr->rdata, &length))
		return 0;
	buffer_printf(output, " ");
	if(!print_unquoted(output, rr->rdlength, rr->rdata, &length))
		return 0;
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int32_t
read_aaaa_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	if (rdlength != 16)
		return MALFORMED;
	return read_rdata(domains, rdlength, packet, rr);
}

int
print_aaaa_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 0;
	assert(rr->rdlength == 16);
	return print_ip6(output, rr->rdlength, rr->rdata, &length);
}

int32_t
read_loc_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	size_t mark;
	uint8_t version;
	uint16_t size_version_0;

	if(!buffer_available(packet, rdlength))
		return MALFORMED;
	/* version (byte) */
	if (rdlength < 1)
		return MALFORMED;
	/* version (byte) + size (byte)
	 * + horizontal precision (byte) + vertical precision (byte)
	 * + latitude (uint32) + longitude (uint32) + altitude (uint32) */
	mark = buffer_position(packet);
	version = buffer_read_u8_at(packet, mark + 0);
	size_version_0 = 16u;
	if (version == 0 && rdlength != size_version_0)
		return MALFORMED;
	return read_rdata(domains, rdlength, packet, rr);
}

/* Print the cm for LOC. */
static void
loc_cm_print(struct buffer* output, uint8_t mantissa, uint8_t exponent)
{
	uint8_t i;
	/* is it 0.<two digits> ? */
	if(exponent < 2) {
		if(exponent == 1)
			mantissa *= 10;
		buffer_printf(output, "0.%02ld", (long)mantissa);
		return;
	}
	/* always <digit><string of zeros> */
	buffer_printf(output, "%d", (int)mantissa);
	for(i=0; i<exponent-2; i++)
		buffer_printf(output, "0");
}

int
print_loc_rdata(struct buffer *output, const struct rr *rr)
{
	/* This does not perform checking (ie degrees < 90 etc). */
	uint8_t version;
	uint8_t size;
	uint8_t horizontal_precision;
	uint8_t vertical_precision;
	uint32_t longitude;
	uint32_t latitude;
	uint32_t altitude;
	char northerness;
	char easterness;
	uint32_t h;
	uint32_t m;
	double s;
	uint32_t equator = (uint32_t)1 << 31; /* 2**31 */

	if(rr->rdlength < 16)
		return 0;
	version = rr->rdata[0];
	if(version != 0)
		return 0;
	size = rr->rdata[1];
	horizontal_precision = rr->rdata[2];
	vertical_precision = rr->rdata[3];

	latitude = read_uint32(rr->rdata+4);
	longitude = read_uint32(rr->rdata+8);
	altitude = read_uint32(rr->rdata+12);

	if (latitude > equator) {
		northerness = 'N';
		latitude = latitude - equator;
	} else {
		northerness = 'S';
		latitude = equator - latitude;
	}
	h = latitude / (1000 * 60 * 60);
	latitude = latitude % (1000 * 60 * 60);
	m = latitude / (1000 * 60);
	latitude = latitude % (1000 * 60);
	s = (double) latitude / 1000.0;
	buffer_printf(output, "%02u %02u %06.3f %c ",
		h, m, s, northerness);

	if (longitude > equator) {
		easterness = 'E';
		longitude = longitude - equator;
	} else {
		easterness = 'W';
		longitude = equator - longitude;
	}
	h = longitude / (1000 * 60 * 60);
	longitude = longitude % (1000 * 60 * 60);
	m = longitude / (1000 * 60);
	longitude = longitude % (1000 * 60);
	s = (double) longitude / (1000.0);
	buffer_printf(output, "%02u %02u %06.3f %c ",
		h, m, s, easterness);

	s = ((double) altitude) / 100;
	s -= 100000;

	if(altitude%100 != 0)
		buffer_printf(output, "%.2f", s);
	else
		buffer_printf(output, "%.0f", s);
	buffer_printf(output, "m ");

	loc_cm_print(output, (size & 0xf0) >> 4, size & 0x0f);
	buffer_printf(output, "m ");

	loc_cm_print(output, (horizontal_precision & 0xf0) >> 4,
		horizontal_precision & 0x0f);
	buffer_printf(output, "m ");

	loc_cm_print(output, (vertical_precision & 0xf0) >> 4,
		vertical_precision & 0x0f);
	buffer_printf(output, "m");

	return 1;
}

int32_t
read_nxt_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	struct domain *domain;
	struct dname_buffer dname;
	size_t size;
	uint16_t bitmap_size;
	const size_t mark = buffer_position(packet);

	/* name + nxt */
	if(!buffer_available(packet, rdlength))
		return MALFORMED;
	if (!dname_make_from_packet_buffered(&dname, packet, 1, 1))
		return MALFORMED;
	if(rdlength < buffer_position(packet) - mark)
		return MALFORMED;
	bitmap_size = rdlength - (buffer_position(packet) - mark);
	size = sizeof(**rr) + sizeof(void*) + bitmap_size;
	if (!(*rr = region_alloc(domains->region, size)))
		return TRUNCATED;
	domain = domain_table_insert(domains, (void*)&dname);
	domain->usage++;
	memcpy((*rr)->rdata, &domain, sizeof(void*));
	if(bitmap_size != 0)
		buffer_read(packet, (*rr)->rdata + sizeof(void*), bitmap_size);
	(*rr)->rdlength = sizeof(void*) + bitmap_size;
	return rdlength;
}

void
write_nxt_rdata(struct query *query, const struct rr *rr)
{
	struct domain *domain;
	const struct dname *dname;

	assert(rr->rdlength >= sizeof(void*));
	memcpy(&domain, rr->rdata, sizeof(void*));
	dname = domain_dname(domain);
	buffer_write(query->packet, dname_name(dname), dname->name_size);
	if(rr->rdlength - sizeof(void*) != 0)
		buffer_write(query->packet, rr->rdata + sizeof(void*),
			rr->rdlength - sizeof(void*));
}

int
print_nxt_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 0;
	int bitmap_size;
	const uint8_t* bitmap;

	assert(rr->rdlength > sizeof(void*));
	if (!print_domain(output, rr->rdlength, rr->rdata, &length))
		return 0;

	bitmap_size = rr->rdlength - length;
	bitmap = rr->rdata + length;
	for (int type = 0; type < bitmap_size * 8; type++) {
		if (get_bit(bitmap, type)) {
			buffer_printf(output, " %s", rrtype_to_string(type));
		}
	}

	return 1;
}

int
print_eid_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 0;
	if(!print_base16(output, rr->rdlength, rr->rdata, &length))
		return 0;
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int
print_nimloc_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 0;
	if(!print_base16(output, rr->rdlength, rr->rdata, &length))
		return 0;
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int32_t
read_srv_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	struct domain *domain;
	struct dname_buffer dname;
	size_t size;
	const size_t mark = buffer_position(packet);

	/* short + short + short + name */
	if (buffer_remaining(packet) < rdlength || rdlength < 6)
		return MALFORMED;
	buffer_skip(packet, 6);
	if (!dname_make_from_packet_buffered(&dname, packet,
		1 /* lenient */, 1) ||
	    rdlength != buffer_position(packet)-mark)
		return MALFORMED;
	size = sizeof(**rr) + 6 + sizeof(void*);
	if (!(*rr = region_alloc(domains->region, size)))
		return TRUNCATED;
	domain = domain_table_insert(domains, (void*)&dname);
	domain->usage++;
	buffer_read_at(packet, mark, (*rr)->rdata, 6);
	memcpy((*rr)->rdata + 6, &domain, sizeof(void*));
	(*rr)->rdlength = 6 + sizeof(void*);
	return rdlength;
}

void
write_srv_rdata(struct query *query, const struct rr *rr)
{
	struct domain *domain;
	const struct dname *dname;

	assert(rr->rdlength == 6 + sizeof(void*));
	memcpy(&domain, rr->rdata + 6, sizeof(void*));
	dname = domain_dname(domain);
	buffer_write(query->packet, rr->rdata, 6);
	buffer_write(query->packet, dname_name(dname), dname->name_size);
}

int
print_srv_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 6;
	assert(rr->rdlength > length);
	buffer_printf(
		output, "%" PRIu16 " %" PRIu16 " %" PRIu16 " ",
		read_uint16(rr->rdata), read_uint16(rr->rdata+2),
		read_uint16(rr->rdata+4));
	if (!print_domain(output, rr->rdlength, rr->rdata, &length))
		return 0;
	assert(rr->rdlength == length);
	return 1;
}

int
print_atma_rdata(struct buffer *output, const struct rr *rr)
{
	uint8_t format;
	if(rr->rdlength < 1)
		return 0;
	format = rr->rdata[0];
	if(format == 0) {
		/* AESA format (ATM End System Address). */
		uint16_t length = 1;
		if (!print_base16(output, rr->rdlength, rr->rdata, &length))
			return 0;
		if(rr->rdlength != length)
			return 0;
		return 1;
	} else if(format == 1) {
		/* E.164 format. */
		/* '+' and then digits '0'-'9' from the rdata string. */
		buffer_printf(output, "+");
		for (size_t i = 1; i < rr->rdlength; i++) {
			char ch = (char)rr->rdata[i];
			if(!isdigit((unsigned char)ch))
				return 0;
			buffer_printf(output, "%c", ch);
		}
		return 1;
	}
	/* Unknown format. */
	return 0;
}

int32_t
read_naptr_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	struct domain *domain;
	struct dname_buffer dname;
	uint16_t length = 4;
	size_t size;
	const size_t mark = buffer_position(packet);

	/* short + short + text + text + text + name */
	if (buffer_remaining(packet) < rdlength ||
	    rdlength < length)
		return MALFORMED;
	buffer_skip(packet, 4);
	if(skip_string(packet, rdlength, &length) < 0 ||
	   skip_string(packet, rdlength, &length) < 0 ||
	   skip_string(packet, rdlength, &length) < 0 ||
	   !dname_make_from_packet_buffered(&dname, packet, 1, 1) ||
	   rdlength != buffer_position(packet) - mark)
		return MALFORMED;

	size = sizeof(**rr) + length + sizeof(void*);
	if (!(*rr = region_alloc(domains->region, size)))
		return TRUNCATED;
	domain = domain_table_insert(domains, (void*)&dname);
	domain->usage++;
	buffer_read_at(packet, mark, (*rr)->rdata, length);
	memcpy((*rr)->rdata + length, &domain, sizeof(void*));
	(*rr)->rdlength = length + sizeof(void*);
	return rdlength;
}

void
write_naptr_rdata(struct query *query, const struct rr *rr)
{
	struct domain *domain;
	const struct dname *dname;
	uint16_t length;

	/* short + short + string + string + string + uncompressed name */
	assert(rr->rdlength >= 7 + sizeof(void*));
	length = rr->rdlength - sizeof(void*);
	memcpy(&domain, rr->rdata + length, sizeof(void*));
	dname = domain_dname(domain);
	buffer_write(query->packet, rr->rdata, length);
	buffer_write(query->packet, dname_name(dname), dname->name_size);
}

int
print_naptr_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 4;

	assert(rr->rdlength >= 7 + sizeof(void*));
	buffer_printf(
		output, "%" PRIu16 " %" PRIu16 " ",
		read_uint16(rr->rdata), read_uint16(rr->rdata+2));
	if (!print_string(output, rr->rdlength, rr->rdata, &length))
		return 0;
	buffer_printf(output, " ");
	if (!print_string(output, rr->rdlength, rr->rdata, &length))
		return 0;
	buffer_printf(output, " ");
	if (!print_string(output, rr->rdlength, rr->rdata, &length))
		return 0;
	buffer_printf(output, " ");
	if (!print_domain(output, rr->rdlength, rr->rdata, &length))
		return 0;
	assert(rr->rdlength == length);
	return 1;
}

int32_t
read_kx_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	struct domain *domain;
	struct dname_buffer dname;
	const size_t mark = buffer_position(packet);
	size_t size;

	/* short + uncompressed name */
	if(buffer_remaining(packet) < rdlength || rdlength < 2)
		return MALFORMED;
	buffer_skip(packet, 2);
	if(!dname_make_from_packet_buffered(&dname, packet,
		1 /* lenient */, 1) ||
	    rdlength != buffer_position(packet) - mark)
		return MALFORMED;

	size = sizeof(**rr) + 2 + sizeof(void*);
	if (!(*rr = region_alloc(domains->region, size)))
		return TRUNCATED;
	domain = domain_table_insert(domains, (void*)&dname);
	domain->usage++;
	buffer_read_at(packet, mark, (*rr)->rdata, 2);
	memcpy((*rr)->rdata + 2, &domain, sizeof(void*));
	(*rr)->rdlength = 2 + sizeof(void*);
	return rdlength;
}

void
write_kx_rdata(struct query *query, const struct rr *rr)
{
	struct domain *domain;
	const struct dname *dname;

	/* short + uncompressed name */
	assert(rr->rdlength == 2 + sizeof(void*));
	memcpy(&domain, rr->rdata + 2, sizeof(void*));
	dname = domain_dname(domain);
	buffer_write(query->packet, rr->rdata, 2);
	buffer_write(query->packet, dname_name(dname), dname->name_size);
}

int32_t
read_cert_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	/* short + short + byte + binary */
	if (rdlength < 5)
		return MALFORMED;
	return read_rdata(domains, rdlength, packet, rr);
}

int
print_cert_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 0;
	if(rr->rdlength < 5)
		return 0;
	if(!print_certificate_type(output, rr->rdlength, rr->rdata, &length))
		return 0;
	buffer_printf(output, " %" PRIu16 " %" PRIu8 " ",
		read_uint16(rr->rdata+2), rr->rdata[4]);
	length += 3;
	if (!print_base64(output, rr->rdlength, rr->rdata, &length))
		return 0;
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int
print_sink_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 2;
	if(rr->rdlength < 2)
		return 0;
	buffer_printf(output, "%" PRIu8 " %" PRIu8 " ",
		rr->rdata[0], rr->rdata[1]);
	if (!print_base64(output, rr->rdlength, rr->rdata, &length))
		return 0;
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int32_t
read_apl_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	uint16_t length = 0;
	const uint8_t *rdata = buffer_current(packet);

	if (buffer_remaining(packet) < rdlength)
		return MALFORMED;
	while (rdlength - length >= 4) {
		uint8_t afdlength = rdata[length + 3] & APL_LENGTH_MASK;
		if (rdlength - (length + 4) < afdlength)
			return MALFORMED;
		length += 4 + afdlength;
	}

	if (length != rdlength)
		return MALFORMED;
	return read_rdata(domains, rdlength, packet, rr);
}

/*
 * Print one APL field.
 * @param output: string is printed to the buffer.
 * @param rdlength: length of rdata.
 * @param rdata: the rdata
 * @param offset: on input the current position, adjusted on output to
 *	increment for the rdata used.
 * @return false on failure.
 */
static int
print_apl(struct buffer *output, size_t rdlength, const uint8_t *rdata,
	uint16_t *offset)
{
	size_t size = rdlength - *offset;
	uint16_t address_family;
	uint8_t prefix, length, negated;
	int af;
	char text_address[INET6_ADDRSTRLEN + 1];
	uint8_t address[16];

	if (size < 4)
		return 0;

	address_family = read_uint16(rdata + *offset);
	prefix = rdata[*offset + 2];
	length = rdata[*offset + 3] & APL_LENGTH_MASK;
	negated = rdata[*offset + 3] & APL_NEGATION_MASK;
	af = -1;

	switch (address_family) {
	case 1: af = AF_INET; break;
	case 2: af = AF_INET6; break;
	}

	if (af == -1 || size - 4 < length)
		return 0;

	memset(address, 0, sizeof(address));
	memmove(address, rdata + *offset + 4, length);

	if (!inet_ntop(af, address, text_address, sizeof(text_address)))
		return 0;

	buffer_printf(
		output, "%s%" PRIu16 ":%s/%" PRIu8,
		(negated ? "!" : ""), address_family, text_address, prefix);
	*offset += 4 + length;
	return 1;
}

int
print_apl_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 0;

	while (length < rr->rdlength) {
		if(length != 0)
			buffer_printf(output, " ");
		if (!print_apl(output, rr->rdlength, rr->rdata, &length))
			return 0;
	}
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int32_t
read_ds_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	/* short + byte + byte + binary */
	if (rdlength < 4)
		return MALFORMED;
	return read_rdata(domains, rdlength, packet, rr);
}

int
print_ds_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 4;

	if(rr->rdlength < length)
		return 0;
	buffer_printf(
		output, "%" PRIu16 " %" PRIu8 " %" PRIu8 " ",
		read_uint16(rr->rdata), rr->rdata[2], rr->rdata[3]);
	if (!print_base16(output, rr->rdlength, rr->rdata, &length))
		return 0;
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int32_t
read_sshfp_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	/* byte + byte + binary */
	if (rdlength < 2)
		return MALFORMED;
	return read_rdata(domains, rdlength, packet, rr);
}

int
print_sshfp_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 2;
	uint8_t algorithm, ftype;

	if(rr->rdlength < length)
		return 0;
	algorithm = rr->rdata[0];
	ftype = rr->rdata[1];

	buffer_printf(output, "%" PRIu8 " %" PRIu8 " ", algorithm, ftype);
	if (!print_base16(output, rr->rdlength, rr->rdata, &length))
		return 0;
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int32_t
read_ipseckey_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	struct dname_buffer gateway;
	const uint8_t *gateway_rdata;
	uint8_t gateway_length = 0;
	const size_t mark = buffer_position(packet);
	uint16_t keylen;

	/* byte + byte + byte + gateway + binary */
	if (buffer_remaining(packet) < rdlength || rdlength < 3)
		return MALFORMED;

	buffer_skip(packet, 3);

	switch (buffer_read_u8_at(packet, mark + 1)) {
	case IPSECKEY_NOGATEWAY:
		gateway_length = 0;
		gateway_rdata = NULL;
		break;
	case IPSECKEY_IP4:
		gateway_length = 4;
		gateway_rdata = buffer_current(packet);
		if (rdlength < 3 + gateway_length)
			return MALFORMED;
		buffer_skip(packet, gateway_length);
		break;
	case IPSECKEY_IP6:
		gateway_length = 16;
		gateway_rdata = buffer_current(packet);
		if (rdlength < 3 + gateway_length)
			return MALFORMED;
		buffer_skip(packet, gateway_length);
		break;
	case IPSECKEY_DNAME:
		/* The dname is stored as literal dname. On the wire
		 * skip possibly compressed format, in the rdata there
		 * is an uncompressed wire format. */
		if (!dname_make_from_packet_buffered(&gateway, packet,
			1 /* lenient */, 0))
			return MALFORMED;
		if(rdlength < buffer_position(packet) - mark)
			return MALFORMED;
		gateway_length = gateway.dname.name_size;
		gateway_rdata = dname_name((void*)&gateway);
		break;
	default:
		return MALFORMED;
	}
	keylen = rdlength - (buffer_position(packet)-mark);

	if (!(*rr = region_alloc(domains->region,
		sizeof(**rr) + 3 + gateway_length + keylen)))
		return TRUNCATED;

	buffer_read_at(packet, mark, (*rr)->rdata, 3);
	if(gateway_rdata)
		memcpy((*rr)->rdata + 3, gateway_rdata, gateway_length);
	if(keylen != 0)
		buffer_read(packet, (*rr)->rdata + 3 + gateway_length, keylen);
	(*rr)->rdlength = 3 + gateway_length + keylen;
	return rdlength;
}

int
print_ipseckey_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 3;
	uint8_t gateway_type;

	if(rr->rdlength < length)
		return 0;
	buffer_printf(
		output, "%" PRIu8 " %" PRIu8 " %" PRIu8 " ",
		rr->rdata[0], rr->rdata[1], rr->rdata[2]);
	gateway_type = rr->rdata[1];
	switch (gateway_type) {
	case IPSECKEY_NOGATEWAY:
		buffer_printf(output, ".");
		break;
	case IPSECKEY_IP4:
		if (!print_ip4(output, rr->rdlength, rr->rdata, &length))
			return 0;
		break;
	case IPSECKEY_IP6:
		if (!print_ip6(output, rr->rdlength, rr->rdata, &length))
			return 0;
		break;
	case IPSECKEY_DNAME:
		if (!print_name_literal(output, rr->rdlength, rr->rdata,
			&length))
			return 0;
		break;
	default:
		return 0;
	}

	if(rr->rdlength > length) {
		/* Print key field in base64. */
		buffer_printf(output, " ");
		if (!print_base64(output, rr->rdlength, rr->rdata, &length))
			return 0;
	}
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int32_t
ipseckey_gateway_length(uint16_t rdlength, const uint8_t *rdata,
	uint16_t offset, struct domain** domain)
{
	/* The ipseckey gateway length depends only on earlier bytes, so both
	 * the in-memory and uncompressed wireformat refer to the same
	 * earlier bytes. Also the domain name is stored literally, so it
	 * does not need to return a reference. */
	uint8_t gateway_type;
	*domain = NULL;
	/* Calculate the gateway length, based on the gateway type.
	 * That is stored in an earlier field. */
	if(rdlength < 3 || offset < 3)
		return -1; /* too short */
	gateway_type = rdata[1];
	switch(gateway_type) {
	case IPSECKEY_NOGATEWAY:
		return 0;
	case IPSECKEY_IP4:
		return 4;
	case IPSECKEY_IP6:
		return 16;
	case IPSECKEY_DNAME:
		return buf_dname_length(rdata+offset, rdlength-offset);
	default:
		/* Unknown gateway type. */
		break;
	}
	return -1;
}

int32_t
read_rrsig_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	struct dname_buffer signer;
	const size_t mark = buffer_position(packet);
	uint16_t memrdlen, b64len;

	/* short + byte + byte + uint32 + uint32 + uint32 + short */
	if (buffer_remaining(packet) < rdlength || rdlength < 18)
		return MALFORMED;
	buffer_skip(packet, 18);
	if (!dname_make_from_packet_buffered(&signer, packet,
		1 /* lenient */, 0))
		return MALFORMED;
	if (rdlength < buffer_position(packet) - mark)
		return MALFORMED;
	memrdlen = 18 + signer.dname.name_size;
	b64len = rdlength - (buffer_position(packet) - mark);
	if (!(*rr = region_alloc(domains->region, sizeof(**rr) + memrdlen + b64len)))
		return TRUNCATED;
	buffer_read_at(packet, mark, (*rr)->rdata, 18);
	memcpy((*rr)->rdata + 18, dname_name((void*)&signer),
		signer.dname.name_size);
	if(b64len != 0)
		buffer_read(packet, (*rr)->rdata+memrdlen, b64len);
	(*rr)->rdlength = memrdlen + b64len;
	return rdlength;
}

int
print_rrsig_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 8;

	if(rr->rdlength < 18)
		return 0;
	buffer_printf(
		output, "%s %" PRIu8 " %" PRIu8 " %" PRIu32 " ",
		rrtype_to_string(read_uint16(rr->rdata)), rr->rdata[2],
		rr->rdata[3], read_uint32(rr->rdata+4));
	if (!print_time(output, rr->rdlength, rr->rdata, &length))
		return 0;
	buffer_printf(output, " ");
	if (!print_time(output, rr->rdlength, rr->rdata, &length))
		return 0;

	buffer_printf(output, " %" PRIu16 " ", read_uint16(rr->rdata+length));
	length += 2;

	if (!print_name_literal(output, rr->rdlength, rr->rdata, &length))
		return 0;
	buffer_printf(output, " ");
	if (!print_base64(output, rr->rdlength, rr->rdata, &length))
		return 0;
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int32_t
read_nsec_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	struct dname_buffer next;
	uint16_t length, memrdlen, bitmaplen;
	size_t bitmapmark;
	const size_t mark = buffer_position(packet);

	/* uncompressed name + nsec */
	if(buffer_remaining(packet) < rdlength ||
	   !dname_make_from_packet_buffered(&next, packet,
		1 /* lenient */, 0 /* The NSEC record can have a non normalized
		dname as the next owner name. And if so this should be
		preserved, so that the RRSIG verifies. */ ) ||
	   rdlength < buffer_position(packet) - mark)
		return MALFORMED;

	bitmapmark = buffer_position(packet);
	length = bitmapmark - mark;
	if (skip_nsec(packet, rdlength, &length) < 0
		|| rdlength != length)
		return MALFORMED;
	bitmaplen = buffer_position(packet) - bitmapmark;
	memrdlen = next.dname.name_size + bitmaplen;
	if (!(*rr = region_alloc(domains->region, sizeof(**rr) + memrdlen)))
		return TRUNCATED;
	memcpy((*rr)->rdata, dname_name((void*)&next), next.dname.name_size);
	if(bitmaplen != 0)
		buffer_read_at(packet, bitmapmark,
			(*rr)->rdata + next.dname.name_size, bitmaplen);
	(*rr)->rdlength = memrdlen;
	return rdlength;
}

int
print_nsec_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 0;

	if (!print_name_literal(output, rr->rdlength, rr->rdata, &length))
		return 0;
	buffer_printf(output, " ");
	if (!print_nsec_bitmap(output, rr->rdlength, rr->rdata, &length))
		return 0;
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int32_t
read_dnskey_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	/* short + byte + byte + binary of remainder */
	if (rdlength < 4)
		return MALFORMED;
	return read_rdata(domains, rdlength, packet, rr);
}

int
print_dnskey_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 4;

	if(rr->rdlength < length)
		return 0;
	buffer_printf(
		output, "%" PRIu16 " %" PRIu8 " %" PRIu8 " ",
		read_uint16(rr->rdata), rr->rdata[2], rr->rdata[3]);
	if (!print_base64(output, rr->rdlength, rr->rdata, &length))
		return 0;
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int32_t
read_dhcid_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	/* short + byte + digest */
	if (rdlength < 3)
		return MALFORMED;
	return read_rdata(domains, rdlength, packet, rr);
}

int
print_dhcid_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 0;

	if (!print_base64(output, rr->rdlength, rr->rdata, &length))
		return 0;
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int32_t
read_nsec3_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	uint16_t length = 4;
	/* byte + byte + short + string + string + binary */
	const size_t mark = buffer_position(packet);

	if (buffer_remaining(packet) < rdlength || rdlength < length)
		return MALFORMED;
	buffer_skip(packet, length);
	if (skip_string(packet, rdlength, &length) < 0 ||
			skip_string(packet, rdlength, &length) < 0 ||
			skip_nsec(packet, rdlength, &length) < 0 ||
			rdlength != length)
		return MALFORMED;
	buffer_set_position(packet, mark);
	return read_rdata(domains, rdlength, packet, rr);
}

int
print_nsec3_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 4;

	if(rr->rdlength < length)
		return 0;
	buffer_printf(
		output, "%" PRIu8 " %" PRIu8 " %" PRIu16 " ",
		rr->rdata[0], rr->rdata[1], read_uint16(rr->rdata + 2));
	if (!print_salt(output, rr->rdlength, rr->rdata, &length))
		return 0;
	buffer_printf(output, " ");
	if (!print_base32(output, rr->rdlength, rr->rdata, &length))
		return 0;
	buffer_printf(output, " ");
	if (!print_nsec_bitmap(output, rr->rdlength, rr->rdata, &length))
		return 0;
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int32_t
read_nsec3param_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	uint16_t length = 4;
	/* byte + byte + short + string */
	const size_t mark = buffer_position(packet);

	if (buffer_remaining(packet) < rdlength || rdlength < length)
		return MALFORMED;
	buffer_skip(packet, length);
	if (skip_string(packet, rdlength, &length) < 0 ||
	    rdlength != length)
		return MALFORMED;
	buffer_set_position(packet, mark);
	return read_rdata(domains, rdlength, packet, rr);
}

int
print_nsec3param_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 4;

	if(rr->rdlength < length)
		return 0;
	buffer_printf(
		output, "%" PRIu8 " %" PRIu8 " %" PRIu16 " ",
		rr->rdata[0], rr->rdata[1], read_uint16(rr->rdata + 2));

	if (!print_salt(output, rr->rdlength, rr->rdata, &length))
		return 0;
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int32_t
read_tlsa_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	/* byte + byte + byte + binary */
	if (rdlength < 3)
		return MALFORMED;
	return read_rdata(domains, rdlength, packet, rr);
}

int
print_tlsa_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 3;

	if(rr->rdlength < length)
		return 0;
	buffer_printf(
		output, "%" PRIu8 " %" PRIu8 " %" PRIu8 " ",
		rr->rdata[0], rr->rdata[1], rr->rdata[2]);

	if (!print_base16(output, rr->rdlength, rr->rdata, &length))
		return 0;
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int32_t
read_hip_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	/* byte (hit length) + byte (PK algorithm) + short (PK length) +
	 * HIT(hex) + pubkey(base64) + rendezvous servers(literal dnames) */
	if (rdlength < 4)
		return MALFORMED;
	return read_rdata(domains, rdlength, packet, rr);
}

int
print_hip_rdata(struct buffer *output, const struct rr *rr)
{
	/* byte (hit length) + byte (PK algorithm) + short (PK length) +
	 * HIT(hex) + pubkey(base64) + rendezvous servers(literal dnames) */
	uint8_t hit_length, pk_algorithm;
	uint16_t pk_length;
	uint16_t length = 4;

	if(rr->rdlength < length)
		return 0;
	hit_length = rr->rdata[0];
	pk_algorithm = rr->rdata[1];
	pk_length = read_uint16(rr->rdata+2);
	buffer_printf(output, "%" PRIu8 " ", pk_algorithm);
	if(!print_base16(output, length+hit_length, rr->rdata, &length))
		return 0;
	buffer_printf(output, " ");
	if(!print_base64(output, length+pk_length, rr->rdata, &length))
		return 0;
	while(length < rr->rdlength) {
		buffer_printf(output, " ");
		if(!print_name_literal(output, rr->rdlength, rr->rdata,
			&length))
			return 0;
	}
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int32_t
read_rkey_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	/* short + byte + byte + binary of remainder */
	if (rdlength < 4)
		return MALFORMED;
	return read_rdata(domains, rdlength, packet, rr);
}

int
print_rkey_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 4;

	if(rr->rdlength < length)
		return 0;
	buffer_printf(
		output, "%" PRIu16 " %" PRIu8 " %" PRIu8 " ",
		read_uint16(rr->rdata), rr->rdata[2], rr->rdata[3]);
	if (!print_base64(output, rr->rdlength, rr->rdata, &length))
		return 0;
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int32_t
read_talink_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	struct dname_buffer prev, next;
	const size_t mark = buffer_position(packet);
	if(!buffer_available(packet, rdlength))
		return MALFORMED;
	if(!dname_make_from_packet_buffered(&prev, packet,
		1 /* lenient */, 0))
		return MALFORMED;
	if(buffer_position(packet)-mark > rdlength)
		return MALFORMED;
	if(!dname_make_from_packet_buffered(&next, packet,
		1 /* lenient */, 0))
		return MALFORMED;
	if(buffer_position(packet)-mark != rdlength)
		return MALFORMED;
	if (!(*rr = region_alloc(domains->region,
		sizeof(**rr) + prev.dname.name_size + next.dname.name_size)))
		return TRUNCATED;
	memcpy((*rr)->rdata, dname_name((void*)&prev), prev.dname.name_size);
	memcpy((*rr)->rdata + prev.dname.name_size, dname_name((void*)&next),
		next.dname.name_size);
	(*rr)->rdlength = prev.dname.name_size + next.dname.name_size;
	return rdlength;
}

int
print_talink_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 0;
	if(!print_name_literal(output, rr->rdlength, rr->rdata, &length))
		return 0;
	buffer_printf(output, " ");
	if(!print_name_literal(output, rr->rdlength, rr->rdata, &length))
		return 0;
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int
print_openpgpkey_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 0;

	if (!print_base64(output, rr->rdlength, rr->rdata, &length))
		return 0;
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int32_t
read_csync_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	/* long + short + binary bitmap in remainder */
	if (rdlength < 6)
		return MALFORMED;
	return read_rdata(domains, rdlength, packet, rr);
}

int
print_csync_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 6;

	if(rr->rdlength < length)
		return 0;
	buffer_printf(
		output, "%" PRIu32 " %" PRIu16 " ",
		read_uint32(rr->rdata), read_uint16(rr->rdata + 4));
	if (!print_nsec_bitmap(output, rr->rdlength, rr->rdata, &length))
		return 0;
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int32_t
read_zonemd_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	/* long + byte + byte + binary */
	if (rdlength < 6)
		return MALFORMED;
	return read_rdata(domains, rdlength, packet, rr);
}

int
print_zonemd_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 6;

	if(rr->rdlength < length)
		return 0;
	buffer_printf(
		output, "%" PRIu32 " %" PRIu8 " %" PRIu8 " ",
		read_uint32(rr->rdata), rr->rdata[4], rr->rdata[5]);
	if (!print_base16(output, rr->rdlength, rr->rdata, &length))
		return 0;
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int32_t
read_svcb_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	struct domain *domain;
	struct dname_buffer target;
	uint16_t length = 2, svcparams_length = 0;
	uint16_t size;
	const size_t mark = buffer_position(packet);

	/* short + name + svc_params */
	if (buffer_remaining(packet) < rdlength || rdlength < length)
		return MALFORMED;
	buffer_skip(packet, length);
	if (!dname_make_from_packet_buffered(&target, packet,
		1 /* lenient */, 1))
		return MALFORMED;
	if(rdlength < buffer_position(packet) - mark)
		return MALFORMED;
	length = buffer_position(packet)-mark;
	/* For secondary, the server should accept the wireformat more
	 * leniently. So this check is skipped. */
	/*
	if(!skip_svcparams(packet, rdlength-length))
		return MALFORMED;
	if(rdlength < buffer_position(packet) - mark)
		return MALFORMED;
	*/
	svcparams_length = rdlength - length;
	buffer_skip(packet, svcparams_length);

	size = sizeof(**rr) + 2 + sizeof(void*) + svcparams_length;
	if (!(*rr = region_alloc(domains->region, size)))
		return TRUNCATED;
	domain = domain_table_insert(domains, (void*)&target);
	domain->usage++;
	buffer_read_at(packet, mark, (*rr)->rdata, 2);
	memcpy((*rr)->rdata + 2, &domain, sizeof(void*));
	if(svcparams_length != 0)
		buffer_read_at(packet, mark + length,
			(*rr)->rdata + 2 + sizeof(void*), svcparams_length);
	(*rr)->rdlength = 2 + sizeof(void*) + svcparams_length;
	return rdlength;
}

void
write_svcb_rdata(struct query *query, const struct rr *rr)
{
	struct domain *domain;
	const struct dname *target;
	uint8_t length;

	assert(rr->rdlength >= 2 + sizeof(void*));
	memcpy(&domain, rr->rdata + 2, sizeof(void*));
	target = domain_dname(domain);
	buffer_write(query->packet, rr->rdata, 2);
	buffer_write(query->packet, dname_name(target), target->name_size);
	length = 2 + sizeof(void*);
	if(rr->rdlength > length)
		buffer_write(query->packet, rr->rdata + length,
			rr->rdlength - length);
}

int
print_svcb_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 2;

	assert(rr->rdlength > length); /* It has 2+sizeof(void*) at least. */
	buffer_printf(output, "%" PRIu16 " ", read_uint16(rr->rdata));
	if (!print_domain(output, rr->rdlength, rr->rdata, &length))
		return 0;
	while (length < rr->rdlength) {
		buffer_printf(output, " ");
		if (!print_svcparam(output, rr->rdlength, rr->rdata, &length))
			return 0;
	}
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int32_t
read_dsync_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	struct dname_buffer target;
	uint16_t length = 5;
	const size_t mark = buffer_position(packet);

	/* type + byte + short + literaldname */
	if (buffer_remaining(packet) < rdlength || rdlength < length)
		return MALFORMED;
	buffer_skip(packet, length);
	if(!dname_make_from_packet_buffered(&target, packet,
		1 /* lenient */, 0) ||
	   rdlength != buffer_position(packet) - mark)
		return MALFORMED;
	length += target.dname.name_size;

	if (!(*rr = region_alloc(domains->region, sizeof(**rr)+length)))
		return TRUNCATED;
	buffer_read_at(packet, mark, (*rr)->rdata, 5);
	memcpy((*rr)->rdata + 5, dname_name((void*)&target),
		target.dname.name_size);
	(*rr)->rdlength = length;
	return rdlength;
}

int
print_dsync_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 5;
	if(rr->rdlength < length)
		return 0;
	buffer_printf(output, "%s %" PRIu8 " %" PRIu16 " ",
		rrtype_to_string(read_uint16(rr->rdata)), rr->rdata[2],
		read_uint16(rr->rdata+3));
	if(!print_name_literal(output, rr->rdlength, rr->rdata, &length))
		return 0;
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int32_t
read_nid_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	if (rdlength != 10)
		return MALFORMED;
	return read_rdata(domains, rdlength, packet, rr);
}

int
print_nid_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 2;

	if(rr->rdlength != 10)
		return 0;
	buffer_printf(output, "%" PRIu16 " ", read_uint16(rr->rdata));
	if (!print_ilnp64(output, rr->rdlength, rr->rdata, &length))
		return 0;
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int32_t
read_l32_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	if (rdlength != 6)
		return MALFORMED;
	return read_rdata(domains, rdlength, packet, rr);
}

int
print_l32_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 2;

	if(rr->rdlength != 6)
		return 0;
	buffer_printf(output, "%" PRIu16 " ", read_uint16(rr->rdata));
	if (!print_ip4(output, rr->rdlength, rr->rdata, &length))
		return 0;
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int32_t
read_l64_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	if (rdlength != 10)
		return MALFORMED;
	return read_rdata(domains, rdlength, packet, rr);
}

int
print_l64_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 2;

	if(rr->rdlength != 10)
		return 0;
	buffer_printf(output, "%" PRIu16 " ", read_uint16(rr->rdata));
	if (!print_ilnp64(output, rr->rdlength, rr->rdata, &length))
		return 0;
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int32_t
read_lp_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	struct domain *domain;
	struct dname_buffer target;
	size_t size;
	/* short + name */
	const size_t mark = buffer_position(packet);

	if (buffer_remaining(packet) < rdlength || rdlength < 2)
		return MALFORMED;
	buffer_skip(packet, 2);
	if (!dname_make_from_packet_buffered(&target, packet,
		1 /* lenient */, 1) ||
	    rdlength != buffer_position(packet) - mark)
		return MALFORMED;
	size = sizeof(**rr) + 2 + sizeof(void*);
	if (!(*rr = region_alloc(domains->region, size)))
		return TRUNCATED;
	domain = domain_table_insert(domains, (void*)&target);
	domain->usage++;
	buffer_read_at(packet, mark, (*rr)->rdata, 2);
	memcpy((*rr)->rdata + 2, &domain, sizeof(void*));
	(*rr)->rdlength = 2 + sizeof(void*);
	return rdlength;
}

void
write_lp_rdata(struct query *query, const struct rr *rr)
{
	struct domain *domain;
	const struct dname *dname;

	/* short + uncompressed name */
	assert(rr->rdlength == 2 + sizeof(void*));
	memcpy(&domain, rr->rdata + 2, sizeof(void*));
	dname = domain_dname(domain);
	buffer_write(query->packet, rr->rdata, 2);
	buffer_write(query->packet, dname_name(dname), dname->name_size);
}

int
print_lp_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 2;

	assert(rr->rdlength == 2 + sizeof(void*));
	buffer_printf(output, "%" PRIu16 " ", read_uint16(rr->rdata));
	if (!print_domain(output, rr->rdlength, rr->rdata, &length))
		return 0;
	assert(rr->rdlength == length);
	return 1;
}

int32_t
read_eui48_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	if (rdlength != 6)
		return MALFORMED;
	return read_rdata(domains, rdlength, packet, rr);
}

int
print_eui48_rdata(struct buffer *output, const struct rr *rr)
{
	const uint8_t *x = rr->rdata;
	if(rr->rdlength != 6)
		return 0;
	buffer_printf(output, "%.2x-%.2x-%.2x-%.2x-%.2x-%.2x",
		x[0], x[1], x[2], x[3], x[4], x[5]);
	return 1;
}

int32_t
read_eui64_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	if (rdlength != 8)
		return MALFORMED;
	return read_rdata(domains, rdlength, packet, rr);
}

int
print_eui64_rdata(struct buffer *output, const struct rr *rr)
{
	const uint8_t *x = rr->rdata;
	if(rr->rdlength != 8)
		return 0;
	buffer_printf(output, "%.2x-%.2x-%.2x-%.2x-%.2x-%.2x-%.2x-%.2x",
		x[0], x[1], x[2], x[3], x[4], x[5], x[6], x[7]);
	return 1;
}

int32_t
read_uri_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	/* short + short + long string */
	if (rdlength < 4)
		return MALFORMED;
	return read_rdata(domains, rdlength, packet, rr);
}

int
print_uri_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 4;

	if(rr->rdlength < length)
		return 0;
	buffer_printf(
		output, "%" PRIu16 " %" PRIu16 " ",
		read_uint16(rr->rdata), read_uint16(rr->rdata + 2));
	if(!print_text(output, rr->rdlength, rr->rdata, &length))
		return 0;
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int
print_resinfo_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 0;
	if(!print_unquoteds(output, rr->rdlength, rr->rdata, &length))
		return 0;
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int32_t
read_caa_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	const size_t mark = buffer_position(packet);
	uint16_t length = 1;

	/* byte + string + long string */
	if (buffer_remaining(packet) < rdlength || rdlength < 2)
		return MALFORMED;
	buffer_skip(packet, 1);
	if (skip_string(packet, rdlength, &length) < 0 || rdlength < length)
		return MALFORMED;
	buffer_set_position(packet, mark);
	return read_rdata(domains, rdlength, packet, rr);
}

int
print_caa_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 1;

	if(rr->rdlength < 2)
		return 0;
	buffer_printf(output, "%" PRIu8 " ", rr->rdata[0]);

	length = 2 + rr->rdata[1];
	if (rr->rdlength < length)
		return 0;

	for (uint16_t i = 2; i < length; ++i) {
		char ch = (char) rr->rdata[i];
		if (isdigit((unsigned char)ch) || islower((unsigned char)ch))
			buffer_printf(output, "%c", ch);
		else	return 0;
	}

	buffer_printf(output, " ");
	if (!print_text(output, rr->rdlength, rr->rdata, &length))
		return 0;
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int
print_doa_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 9;
	if(rr->rdlength < length)
		return 0;
	buffer_printf(output, "%" PRIu32 " %" PRIu32 " %" PRIu8 " ",
		read_uint32(rr->rdata), read_uint32(rr->rdata+4),
		rr->rdata[8]);
	if(!print_string(output, rr->rdlength, rr->rdata, &length))
		return 0;
	buffer_printf(output, " ");
	if(rr->rdlength == length) {
		/* The base64 string is empty, and DOA uses '-' for that. */
		buffer_printf(output, "-");
	} else {
		if(!print_base64(output, rr->rdlength, rr->rdata, &length))
			return 0;
	}
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int32_t
read_amtrelay_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	struct dname_buffer relay;
	const uint8_t *relay_rdata;
	uint8_t relay_length = 0;
	const size_t mark = buffer_position(packet);

	/* byte + byte + relay */
	if (buffer_remaining(packet) < rdlength || rdlength < 2)
		return MALFORMED;

	buffer_skip(packet, 2);

	switch (buffer_read_u8_at(packet, mark + 1)&AMTRELAY_TYPE_MASK) {
	case AMTRELAY_NOGATEWAY:
		relay_length = 0;
		relay_rdata = NULL;
		break;
	case AMTRELAY_IP4:
		relay_length = 4;
		relay_rdata = buffer_current(packet);
		if (rdlength < 2 + relay_length)
			return MALFORMED;
		buffer_skip(packet, relay_length);
		break;
	case AMTRELAY_IP6:
		relay_length = 16;
		relay_rdata = buffer_current(packet);
		if (rdlength < 2 + relay_length)
			return MALFORMED;
		buffer_skip(packet, relay_length);
		break;
	case AMTRELAY_DNAME:
		/* The dname is stored as literal dname. On the wire
		 * skip possibly compressed format, in the rdata there
		 * is an uncompressed wire format. */
		if(!dname_make_from_packet_buffered(&relay, packet,
			1 /* lenient */, 0))
			return MALFORMED;
		if(rdlength < buffer_position(packet) - mark)
			return MALFORMED;
		relay_length = relay.dname.name_size;
		relay_rdata = dname_name((void*)&relay);
		break;
	default:
		return MALFORMED;
	}
	if(rdlength != buffer_position(packet) - mark)
		return MALFORMED; /* trailing bytes */

	if (!(*rr = region_alloc(domains->region,
		sizeof(**rr) + 2 + relay_length)))
		return TRUNCATED;

	buffer_read_at(packet, mark, (*rr)->rdata, 2);
	if(relay_rdata)
		memcpy((*rr)->rdata + 2, relay_rdata, relay_length);
	(*rr)->rdlength = 2 + relay_length;
	return rdlength;
}

int
print_amtrelay_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 2;
	uint8_t relay_type;

	if(rr->rdlength < length)
		return 0;
	relay_type = rr->rdata[1]&AMTRELAY_TYPE_MASK;
	buffer_printf(output, "%" PRIu8 " %c %" PRIu8,
		rr->rdata[0],
		(rr->rdata[1] & AMTRELAY_DISCOVERY_OPTIONAL_MASK ? '1' : '0'),
		relay_type);
	switch(relay_type) {
	case AMTRELAY_NOGATEWAY:
		buffer_printf(output, " .");
		break;
	case AMTRELAY_IP4:
		buffer_printf(output, " ");
		if(!print_ip4(output, rr->rdlength, rr->rdata, &length))
			return 0;
		break;
	case AMTRELAY_IP6:
		buffer_printf(output, " ");
		if(!print_ip6(output, rr->rdlength, rr->rdata, &length))
			return 0;
		break;
	case AMTRELAY_DNAME:
		buffer_printf(output, " ");
		if(!print_name_literal(output, rr->rdlength, rr->rdata,
			&length))
			return 0;
		break;
	default:
		return 0;
	}

	if(rr->rdlength != length)
		return 0;
	return 1;
}

int32_t
amtrelay_relay_length(uint16_t rdlength, const uint8_t *rdata, uint16_t offset,
	struct domain** domain)
{
	/* The amtrelay relay length depends only on earlier bytes, so both
	 * the in-memory and uncompressed wireformat refer to the same
	 * earlier bytes. Also the domain name is stored literally, so it
	 * does not need to return a reference. */
	uint8_t relay_type;
	*domain = NULL;
	/* Calculate the relay length, based on the relay type.
	 * That is stored in an earlier field. */
	if(rdlength < 2 || offset < 2)
		return -1; /* too short */
	relay_type = rdata[1]&AMTRELAY_TYPE_MASK;
	switch(relay_type) {
	case AMTRELAY_NOGATEWAY:
		return 0;
	case AMTRELAY_IP4:
		return 4;
	case AMTRELAY_IP6:
		return 16;
	case AMTRELAY_DNAME:
		return buf_dname_length(rdata+offset, rdlength-offset);
	default:
		/* Unknown relay type. */
		break;
	}
	return -1;
}

int
print_ipn_rdata(struct buffer *output, const struct rr *rr)
{
	uint64_t data;

	if(rr->rdlength < sizeof(data))
		return 0;
	data = read_uint64(rr->rdata);
	buffer_printf(output, "%llu", (unsigned long long) data);
	return 1;
}

int32_t
read_dlv_rdata(struct domain_table *domains, uint16_t rdlength,
	struct buffer *packet, struct rr **rr)
{
	/* short + byte + byte + binary */
	if (rdlength < 4)
		return MALFORMED;
	return read_rdata(domains, rdlength, packet, rr);
}

int
print_dlv_rdata(struct buffer *output, const struct rr *rr)
{
	uint16_t length = 4;

	if(rr->rdlength < length)
		return 0;
	buffer_printf(
		output, "%" PRIu16 " %" PRIu8 " %" PRIu8 " ",
		read_uint16(rr->rdata), rr->rdata[2], rr->rdata[3]);
	if (!print_base16(output, rr->rdlength, rr->rdata, &length))
		return 0;
	if(rr->rdlength != length)
		return 0;
	return 1;
}

int
print_rdata(buffer_type *output, const nsd_type_descriptor_type *descriptor,
	const rr_type *rr)
{
	size_t saved_position = buffer_position(output);
	/* If print_rdata is going to print "", omit the tab printout. */
	if(!(rr->type == TYPE_APL && rr->rdlength == 0))
		buffer_printf(output, "\t");
	if(!descriptor->print_rdata(output, rr)) {
		buffer_set_position(output, saved_position);
		return 0;
	}
	return 1;
}

/*
 * Compare two wireformat byte strings. In canonical order for this comparison.
 * Sorts equal as equal, and if there is a prefix match, the shorter one is
 * before the longer one; so it sorts like normalized domain names,
 * ab ac acd ace ad ae af.  And ab < abc , abc < ac .
 * @param b1: byte string1.
 * @param len1: length of b1.
 * @param b2: byte string2.
 * @param len2: length of b2
 * @return comparison, -1, 0, 1.
 */
static int
compare_bytestring(const uint8_t* b1, uint16_t len1, const uint8_t* b2,
	uint16_t len2)
{
	uint16_t blen;
	int res;

	if(len1 == 0 && len2 == 0)
		return 0;
	if(len1 == 0 && len2 != 0)
		return -1;
	if(len1 != 0 && len2 == 0)
		return 1;
	blen = len1;
	if(len2 < blen)
		blen = len2;
	res = memcmp(b1, b2, blen);
	if(res != 0)
		return res;
	if(len1 < len2)
		return -1;
	if(len1 > len2)
		return 1;
	/* len1 == len2 and equal. */
	return 0;
}

int
equal_rr_rdata(const nsd_type_descriptor_type *descriptor,
	const struct rr *rr1, const struct rr *rr2)
{
	size_t i;
	uint16_t offset = 0;
	int res;

	if(!descriptor->has_references) {
		/* Compare the wireformat of the rdata. */
		res = compare_bytestring(rr1->rdata, rr1->rdlength,
			rr2->rdata, rr2->rdlength);
		if(res != 0)
			return 0;
		return 1;
	}

	for(i=0; i < descriptor->rdata.length; i++) {
		uint16_t field_len1, field_len2;
		struct domain* domain1, *domain2;
		int malf1 = 0, malf2 = 0;
		/* The fields are equal up to this point. */
		if((rr1->rdlength == offset || rr2->rdlength == offset) &&
			descriptor->rdata.fields[i].is_optional) {
			/* There are no more rdata fields. */
			/* Check lengths. */
			if(rr1->rdlength == rr2->rdlength)
				return 1;
			else
				return 0;
		}
		if(!lookup_rdata_field_entry(descriptor, i, rr1, offset,
			&field_len1, &domain1))
			malf1 = 1; /* malformed rdata buffer */
		if(!lookup_rdata_field_entry(descriptor, i, rr2, offset,
			&field_len2, &domain2))
			malf2 = 1; /* malformed rdata buffer */
		if(malf1 || malf2) {
			/* Malformed entries sort last, and are sorted
			 * equal with other malformed entries. */
			if(malf1 && malf2)
				return 1;
			else
				return 0;
		}
		/* Compare the two fields. */
		/* If they have a different type field, they are not the
		 * same. */
		if(domain1 && !domain2)
			return 0;
		if(!domain1 && domain2)
			return 0;
		if(domain1 && domain2) {
			/* Handle RDATA_COMPRESSED_DNAME and
			 * RDATA_UNCOMPRESSED_DNAME fields. */
			res = dname_compare(domain_dname(domain1),
				domain_dname(domain2));
			if(res != 0)
				return 0;
		} else {
			res = compare_bytestring(rr1->rdata + offset,
				field_len1, rr2->rdata + offset, field_len2);
			if(res != 0)
				return 0;
		}
		/* The fields are equal, field_len1 == field_len2. */
		offset += field_len1;
	}
	return 1;
}

int
equal_rr_rdata_uncompressed_wire(const nsd_type_descriptor_type *descriptor,
	const struct rr *rr1, const uint8_t* rr2_rdata, uint16_t rr2_rdlen)
{
	size_t i;
	uint16_t offset1 = 0, offset2 = 0;
	int res;

	if(!descriptor->has_references) {
		/* Compare the wireformat of the rdata. */
		res = compare_bytestring(rr1->rdata, rr1->rdlength,
			rr2_rdata, rr2_rdlen);
		if(res != 0)
			return 0;
		return 1;
	}

	for(i=0; i < descriptor->rdata.length; i++) {
		uint16_t field_len1, field_len2;
		struct domain* domain1, *domain2;
		int malf1 = 0, malf2 = 0;
		/* The fields are equal up to this point. */
		if((rr1->rdlength == offset1 || rr2_rdlen == offset2) &&
			descriptor->rdata.fields[i].is_optional) {
			/* There are no more rdata fields. */
			/* Check lengths. */
			int remain1 = rr1->rdlength - offset1;
			int remain2 = rr2_rdlen - offset2;
			if(remain1 < remain2)
				return 0;
			if(remain1 > remain2)
				return 0;
			/* It is equal. */
			return 1;
		}
		if(!lookup_rdata_field_entry(descriptor, i, rr1, offset1,
			&field_len1, &domain1))
			malf1 = 1; /* malformed rdata buffer */
		if(!lookup_rdata_field_entry_uncompressed_wire(descriptor, i,
			rr2_rdata, rr2_rdlen, offset2, &field_len2, &domain2))
			malf2 = 1; /* malformed rdata buffer */
		if(malf1 || malf2) {
			/* Malformed entries sort last, and are sorted
			 * equal with other malformed entries. */
			if(!malf1 && malf2)
				return 0;
			if(malf1 && !malf2)
				return 0;
			return 1;
		}
		/* Compare the two fields. */
		/* If they have a different type field, they are not the
		 * same. */
		if(domain1) {
			if(domain2) {
				/* Handle RDATA_COMPRESSED_DNAME and
				 * RDATA_UNCOMPRESSED_DNAME fields. */
				res = dname_compare(domain_dname(domain1),
					domain_dname(domain2));
				if(res != 0)
					return 0;
			} else {
				uint16_t dname_len2 = buf_dname_length(
					rr2_rdata+offset2,
					rr2_rdlen-offset2);
				if(domain_dname(domain1)->name_size !=
					dname_len2) {
					/* not the same length dnames. */
					return 0;
				}
				if(!dname_equal_nocase(
					(uint8_t*)dname_name(domain_dname(
						domain1)),
					(uint8_t*)rr2_rdata+offset2,
					dname_len2)) {
					/* name comparison not equal. */
					return 0;
				}
			}
		} else {
			if(domain2) {
				uint16_t dname_len1 = buf_dname_length(
					rr1->rdata + offset1,
					rr1->rdlength-offset1);
				if(dname_len1 !=
					domain_dname(domain2)->name_size) {
					/* not the same length dnames. */
					return 0;
				}
				if(!dname_equal_nocase(
					(uint8_t*)rr1->rdata+offset1,
					(uint8_t*)dname_name(domain_dname(
						domain2)),
					dname_len1)) {
					/* name comparison not equal. */
					return 0;
				}
			} else {
				res = compare_bytestring(rr1->rdata + offset1,
					field_len1, rr2_rdata + offset2,
					field_len2);
				if(res != 0)
					return 0;
			}
		}
		offset1 += field_len1;
		offset2 += field_len2;
	}
	return 1;
}

struct domain*
retrieve_rdata_ref_domain_offset(const struct rr* rr, uint16_t offset)
{
	struct domain *domain;
	if(rr->rdlength < offset+sizeof(void*))
		return NULL;
	memcpy(&domain, rr->rdata+offset, sizeof(void*));
	return domain;
}

struct domain*
retrieve_rdata_ref_domain(const struct rr* rr)
{
	struct domain *domain;
	if(rr->rdlength < sizeof(void*))
		return NULL;
	memcpy(&domain, rr->rdata, sizeof(void*));
	return domain;
}

struct domain*
retrieve_ns_ref_domain(const struct rr* rr)
{
	assert(rr->type == TYPE_NS);
	return retrieve_rdata_ref_domain(rr);
}

struct domain*
retrieve_cname_ref_domain(const struct rr* rr)
{
	assert(rr->type == TYPE_CNAME);
	return retrieve_rdata_ref_domain(rr);
}

struct domain*
retrieve_dname_ref_domain(const struct rr* rr)
{
	assert(rr->type == TYPE_DNAME);
	return retrieve_rdata_ref_domain(rr);
}

struct domain*
retrieve_mb_ref_domain(const struct rr* rr)
{
	assert(rr->type == TYPE_MB);
	return retrieve_rdata_ref_domain(rr);
}

struct domain*
retrieve_mx_ref_domain(const struct rr* rr)
{
	assert(rr->type == TYPE_MX);
	return retrieve_rdata_ref_domain_offset(rr, 2);
}

struct domain*
retrieve_kx_ref_domain(const struct rr* rr)
{
	assert(rr->type == TYPE_KX);
	return retrieve_rdata_ref_domain_offset(rr, 2);
}

struct domain*
retrieve_rt_ref_domain(const struct rr* rr)
{
	assert(rr->type == TYPE_RT);
	return retrieve_rdata_ref_domain_offset(rr, 2);
}

struct domain*
retrieve_srv_ref_domain(const struct rr* rr)
{
	assert(rr->type == TYPE_SRV);
	return retrieve_rdata_ref_domain_offset(rr, 6);
}

struct domain*
retrieve_ptr_ref_domain(const struct rr* rr)
{
	assert(rr->type == TYPE_PTR);
	return retrieve_rdata_ref_domain(rr);
}

int
retrieve_soa_rdata_serial(const struct rr* rr, uint32_t* serial)
{
	assert(rr->type == TYPE_SOA);
	if(rr->rdlength < 20 + 2*sizeof(void*))
		return 0;
	/* primary mail serial[4] refresh[4] retry[4] expire[4] minimum[4] */
	*serial = read_uint32(rr->rdata+2*sizeof(void*));
	return 1;
}

int
retrieve_soa_rdata_minttl(const struct rr* rr, uint32_t* minttl)
{
	assert(rr->type == TYPE_SOA);
	if(rr->rdlength < 20 + 2*sizeof(void*))
		return 0;
	/* primary mail serial[4] refresh[4] retry[4] expire[4] minimum[4] */
	*minttl = read_uint32(rr->rdata+2*sizeof(void*)+16);
	return 1;
}

struct dname* retrieve_cname_ref_dname(const struct rr* rr)
{
	struct domain* domain;
	assert(rr->type == TYPE_CNAME);
	domain = retrieve_rdata_ref_domain(rr);
	if(!domain)
		return NULL;
	return domain_dname(domain);
}

void
rr_lower_usage(namedb_type* db, rr_type* rr)
{
	const nsd_type_descriptor_type *descriptor =
		nsd_type_descriptor(rr->type);
	uint16_t offset = 0;
	size_t i;
	for(i=0; i<descriptor->rdata.length; i++) {
		uint16_t field_len;
		struct domain* domain;
		if(rr->rdlength == offset &&
			descriptor->rdata.fields[i].is_optional)
			break;
		if(!lookup_rdata_field_entry(descriptor, i, rr, offset,
			&field_len, &domain))
			break;
		if(domain) {
			assert(domain->usage > 0);
			domain->usage --;
			if(domain->usage == 0)
				domain_table_deldomain(db,
					domain);
		}
		offset += field_len;
	}
}

const char*
read_rdata_fail_str(int32_t code)
{
	switch(code) {
	case TRUNCATED:
		return "out of memory";
	case MALFORMED:
		return "malformed rdata fields";
	default:
		break;
	}
	return "failed to read rdata fields";
}