xref: /freebsd-10.1-release/contrib/ldns/dnssec.c

/*
 * dnssec.c
 *
 * contains the cryptographic function needed for DNSSEC in ldns
 * The crypto library used is openssl
 *
 * (c) NLnet Labs, 2004-2008
 *
 * See the file LICENSE for the license
 */

#include <ldns/config.h>

#include <ldns/ldns.h>
#include <ldns/dnssec.h>

#include <strings.h>
#include <time.h>

#ifdef HAVE_SSL
#include <openssl/ssl.h>
#include <openssl/evp.h>
#include <openssl/rand.h>
#include <openssl/err.h>
#include <openssl/md5.h>
#endif

ldns_rr *
ldns_dnssec_get_rrsig_for_name_and_type(const ldns_rdf *name,
                                        const ldns_rr_type type,
                                        const ldns_rr_list *rrs)
{
	size_t i;
	ldns_rr *candidate;

	if (!name || !rrs) {
		return NULL;
	}

	for (i = 0; i < ldns_rr_list_rr_count(rrs); i++) {
		candidate = ldns_rr_list_rr(rrs, i);
		if (ldns_rr_get_type(candidate) == LDNS_RR_TYPE_RRSIG) {
			if (ldns_dname_compare(ldns_rr_owner(candidate),
			                       name) == 0 &&
			    ldns_rdf2rr_type(ldns_rr_rrsig_typecovered(candidate))
			    == type
			    ) {
				return candidate;
			}
		}
	}

	return NULL;
}

ldns_rr *
ldns_dnssec_get_dnskey_for_rrsig(const ldns_rr *rrsig,
						   const ldns_rr_list *rrs)
{
	size_t i;
	ldns_rr *candidate;

	if (!rrsig || !rrs) {
		return NULL;
	}

	for (i = 0; i < ldns_rr_list_rr_count(rrs); i++) {
		candidate = ldns_rr_list_rr(rrs, i);
		if (ldns_rr_get_type(candidate) == LDNS_RR_TYPE_DNSKEY) {
			if (ldns_dname_compare(ldns_rr_owner(candidate),
			                       ldns_rr_rrsig_signame(rrsig)) == 0 &&
			    ldns_rdf2native_int16(ldns_rr_rrsig_keytag(rrsig)) ==
			    ldns_calc_keytag(candidate)
			    ) {
				return candidate;
			}
		}
	}

	return NULL;
}

ldns_rdf *
ldns_nsec_get_bitmap(ldns_rr *nsec) {
	if (ldns_rr_get_type(nsec) == LDNS_RR_TYPE_NSEC) {
		return ldns_rr_rdf(nsec, 1);
	} else if (ldns_rr_get_type(nsec) == LDNS_RR_TYPE_NSEC3) {
		return ldns_rr_rdf(nsec, 5);
	} else {
		return NULL;
	}
}

/*return the owner name of the closest encloser for name from the list of rrs */
/* this is NOT the hash, but the original name! */
ldns_rdf *
ldns_dnssec_nsec3_closest_encloser(ldns_rdf *qname,
                                   ATTR_UNUSED(ldns_rr_type qtype),
                                   ldns_rr_list *nsec3s)
{
	/* remember parameters, they must match */
	uint8_t algorithm;
	uint32_t iterations;
	uint8_t salt_length;
	uint8_t *salt;

	ldns_rdf *sname, *hashed_sname, *tmp;
	bool flag;

	bool exact_match_found;
	bool in_range_found;

	ldns_status status;
	ldns_rdf *zone_name;

	size_t nsec_i;
	ldns_rr *nsec;
	ldns_rdf *result = NULL;

	if (!qname || !nsec3s || ldns_rr_list_rr_count(nsec3s) < 1) {
		return NULL;
	}

	nsec = ldns_rr_list_rr(nsec3s, 0);
	algorithm = ldns_nsec3_algorithm(nsec);
	salt_length = ldns_nsec3_salt_length(nsec);
	salt = ldns_nsec3_salt_data(nsec);
	iterations = ldns_nsec3_iterations(nsec);

	sname = ldns_rdf_clone(qname);

	flag = false;

	zone_name = ldns_dname_left_chop(ldns_rr_owner(nsec));

	/* algorithm from nsec3-07 8.3 */
	while (ldns_dname_label_count(sname) > 0) {
		exact_match_found = false;
		in_range_found = false;

		hashed_sname = ldns_nsec3_hash_name(sname,
									 algorithm,
									 iterations,
									 salt_length,
									 salt);

		status = ldns_dname_cat(hashed_sname, zone_name);
                if(status != LDNS_STATUS_OK) {
	                LDNS_FREE(salt);
	                ldns_rdf_deep_free(zone_name);
	                ldns_rdf_deep_free(sname);
                        return NULL;
                }

		for (nsec_i = 0; nsec_i < ldns_rr_list_rr_count(nsec3s); nsec_i++) {
			nsec = ldns_rr_list_rr(nsec3s, nsec_i);

			/* check values of iterations etc! */

			/* exact match? */
			if (ldns_dname_compare(ldns_rr_owner(nsec), hashed_sname) == 0) {
			 	exact_match_found = true;
			} else if (ldns_nsec_covers_name(nsec, hashed_sname)) {
				in_range_found = true;
			}

		}
		if (!exact_match_found && in_range_found) {
			flag = true;
		} else if (exact_match_found && flag) {
			result = ldns_rdf_clone(sname);
			/* RFC 5155: 8.3. 2.** "The proof is complete" */
			ldns_rdf_deep_free(hashed_sname);
			goto done;
		} else if (exact_match_found && !flag) {
			/* error! */
			ldns_rdf_deep_free(hashed_sname);
			goto done;
		} else {
			flag = false;
		}

		ldns_rdf_deep_free(hashed_sname);
		tmp = sname;
		sname = ldns_dname_left_chop(sname);
		ldns_rdf_deep_free(tmp);
	}

	done:
	LDNS_FREE(salt);
	ldns_rdf_deep_free(zone_name);
	ldns_rdf_deep_free(sname);

	return result;
}

bool
ldns_dnssec_pkt_has_rrsigs(const ldns_pkt *pkt)
{
	size_t i;
	for (i = 0; i < ldns_pkt_ancount(pkt); i++) {
		if (ldns_rr_get_type(ldns_rr_list_rr(ldns_pkt_answer(pkt), i)) ==
		    LDNS_RR_TYPE_RRSIG) {
			return true;
		}
	}
	for (i = 0; i < ldns_pkt_nscount(pkt); i++) {
		if (ldns_rr_get_type(ldns_rr_list_rr(ldns_pkt_authority(pkt), i)) ==
		    LDNS_RR_TYPE_RRSIG) {
			return true;
		}
	}
	return false;
}

ldns_rr_list *
ldns_dnssec_pkt_get_rrsigs_for_name_and_type(const ldns_pkt *pkt,
									ldns_rdf *name,
									ldns_rr_type type)
{
	uint16_t t_netorder;
	ldns_rr_list *sigs;
	ldns_rr_list *sigs_covered;
	ldns_rdf *rdf_t;

	sigs = ldns_pkt_rr_list_by_name_and_type(pkt,
									 name,
									 LDNS_RR_TYPE_RRSIG,
									 LDNS_SECTION_ANY_NOQUESTION
									 );

	t_netorder = htons(type); /* rdf are in network order! */
	rdf_t = ldns_rdf_new(LDNS_RDF_TYPE_TYPE, LDNS_RDF_SIZE_WORD, &t_netorder);
	sigs_covered = ldns_rr_list_subtype_by_rdf(sigs, rdf_t, 0);

	ldns_rdf_free(rdf_t);
	ldns_rr_list_deep_free(sigs);

	return sigs_covered;

}

ldns_rr_list *
ldns_dnssec_pkt_get_rrsigs_for_type(const ldns_pkt *pkt, ldns_rr_type type)
{
	uint16_t t_netorder;
	ldns_rr_list *sigs;
	ldns_rr_list *sigs_covered;
	ldns_rdf *rdf_t;

	sigs = ldns_pkt_rr_list_by_type(pkt,
	                                LDNS_RR_TYPE_RRSIG,
	                                LDNS_SECTION_ANY_NOQUESTION
							  );

	t_netorder = htons(type); /* rdf are in network order! */
	rdf_t = ldns_rdf_new(LDNS_RDF_TYPE_TYPE,
					 2,
					 &t_netorder);
	sigs_covered = ldns_rr_list_subtype_by_rdf(sigs, rdf_t, 0);

	ldns_rdf_free(rdf_t);
	ldns_rr_list_deep_free(sigs);

	return sigs_covered;

}

/* used only on the public key RR */
uint16_t
ldns_calc_keytag(const ldns_rr *key)
{
	uint16_t ac16;
	ldns_buffer *keybuf;
	size_t keysize;

	if (!key) {
		return 0;
	}

	if (ldns_rr_get_type(key) != LDNS_RR_TYPE_DNSKEY &&
	    ldns_rr_get_type(key) != LDNS_RR_TYPE_KEY
	    ) {
		return 0;
	}

	/* rdata to buf - only put the rdata in a buffer */
	keybuf = ldns_buffer_new(LDNS_MIN_BUFLEN); /* grows */
	if (!keybuf) {
		return 0;
	}
	(void)ldns_rr_rdata2buffer_wire(keybuf, key);
	/* the current pos in the buffer is the keysize */
	keysize= ldns_buffer_position(keybuf);

	ac16 = ldns_calc_keytag_raw(ldns_buffer_begin(keybuf), keysize);
	ldns_buffer_free(keybuf);
	return ac16;
}

uint16_t ldns_calc_keytag_raw(uint8_t* key, size_t keysize)
{
	unsigned int i;
	uint32_t ac32;
	uint16_t ac16;

	if(keysize < 4) {
		return 0;
	}
	/* look at the algorithm field, copied from 2535bis */
	if (key[3] == LDNS_RSAMD5) {
		ac16 = 0;
		if (keysize > 4) {
			memmove(&ac16, key + keysize - 3, 2);
		}
		ac16 = ntohs(ac16);
		return (uint16_t) ac16;
	} else {
		ac32 = 0;
		for (i = 0; (size_t)i < keysize; ++i) {
			ac32 += (i & 1) ? key[i] : key[i] << 8;
		}
		ac32 += (ac32 >> 16) & 0xFFFF;
		return (uint16_t) (ac32 & 0xFFFF);
	}
}

#ifdef HAVE_SSL
DSA *
ldns_key_buf2dsa(ldns_buffer *key)
{
	return ldns_key_buf2dsa_raw((unsigned char*)ldns_buffer_begin(key),
						   ldns_buffer_position(key));
}

DSA *
ldns_key_buf2dsa_raw(unsigned char* key, size_t len)
{
	uint8_t T;
	uint16_t length;
	uint16_t offset;
	DSA *dsa;
	BIGNUM *Q; BIGNUM *P;
	BIGNUM *G; BIGNUM *Y;

	if(len == 0)
		return NULL;
	T = (uint8_t)key[0];
	length = (64 + T * 8);
	offset = 1;

	if (T > 8) {
		return NULL;
	}
	if(len < (size_t)1 + SHA_DIGEST_LENGTH + 3*length)
		return NULL;

	Q = BN_bin2bn(key+offset, SHA_DIGEST_LENGTH, NULL);
	offset += SHA_DIGEST_LENGTH;

	P = BN_bin2bn(key+offset, (int)length, NULL);
	offset += length;

	G = BN_bin2bn(key+offset, (int)length, NULL);
	offset += length;

	Y = BN_bin2bn(key+offset, (int)length, NULL);
	offset += length;

	/* create the key and set its properties */
	if(!Q || !P || !G || !Y || !(dsa = DSA_new())) {
		BN_free(Q);
		BN_free(P);
		BN_free(G);
		BN_free(Y);
		return NULL;
	}
#ifndef S_SPLINT_S
	dsa->p = P;
	dsa->q = Q;
	dsa->g = G;
	dsa->pub_key = Y;
#endif /* splint */

	return dsa;
}

RSA *
ldns_key_buf2rsa(ldns_buffer *key)
{
	return ldns_key_buf2rsa_raw((unsigned char*)ldns_buffer_begin(key),
						   ldns_buffer_position(key));
}

RSA *
ldns_key_buf2rsa_raw(unsigned char* key, size_t len)
{
	uint16_t offset;
	uint16_t exp;
	uint16_t int16;
	RSA *rsa;
	BIGNUM *modulus;
	BIGNUM *exponent;

	if (len == 0)
		return NULL;
	if (key[0] == 0) {
		if(len < 3)
			return NULL;
		/* need some smart comment here XXX*/
		/* the exponent is too large so it's places
		 * futher...???? */
		memmove(&int16, key+1, 2);
		exp = ntohs(int16);
		offset = 3;
	} else {
		exp = key[0];
		offset = 1;
	}

	/* key length at least one */
	if(len < (size_t)offset + exp + 1)
		return NULL;

	/* Exponent */
	exponent = BN_new();
	if(!exponent) return NULL;
	(void) BN_bin2bn(key+offset, (int)exp, exponent);
	offset += exp;

	/* Modulus */
	modulus = BN_new();
	if(!modulus) {
		BN_free(exponent);
		return NULL;
	}
	/* length of the buffer must match the key length! */
	(void) BN_bin2bn(key+offset, (int)(len - offset), modulus);

	rsa = RSA_new();
	if(!rsa) {
		BN_free(exponent);
		BN_free(modulus);
		return NULL;
	}
#ifndef S_SPLINT_S
	rsa->n = modulus;
	rsa->e = exponent;
#endif /* splint */

	return rsa;
}

int
ldns_digest_evp(unsigned char* data, unsigned int len, unsigned char* dest,
	const EVP_MD* md)
{
	EVP_MD_CTX* ctx;
	ctx = EVP_MD_CTX_create();
	if(!ctx)
		return false;
	if(!EVP_DigestInit_ex(ctx, md, NULL) ||
		!EVP_DigestUpdate(ctx, data, len) ||
		!EVP_DigestFinal_ex(ctx, dest, NULL)) {
		EVP_MD_CTX_destroy(ctx);
		return false;
	}
	EVP_MD_CTX_destroy(ctx);
	return true;
}
#endif /* HAVE_SSL */

ldns_rr *
ldns_key_rr2ds(const ldns_rr *key, ldns_hash h)
{
	ldns_rdf *tmp;
	ldns_rr *ds;
	uint16_t keytag;
	uint8_t  sha1hash;
	uint8_t *digest;
	ldns_buffer *data_buf;
#ifdef USE_GOST
	const EVP_MD* md = NULL;
#endif

	if (ldns_rr_get_type(key) != LDNS_RR_TYPE_DNSKEY) {
		return NULL;
	}

	ds = ldns_rr_new();
	if (!ds) {
		return NULL;
	}
	ldns_rr_set_type(ds, LDNS_RR_TYPE_DS);
	ldns_rr_set_owner(ds, ldns_rdf_clone(
								  ldns_rr_owner(key)));
	ldns_rr_set_ttl(ds, ldns_rr_ttl(key));
	ldns_rr_set_class(ds, ldns_rr_get_class(key));

	switch(h) {
	default:
	case LDNS_SHA1:
		digest = LDNS_XMALLOC(uint8_t, LDNS_SHA1_DIGEST_LENGTH);
		if (!digest) {
			ldns_rr_free(ds);
			return NULL;
		}
		break;
	case LDNS_SHA256:
		digest = LDNS_XMALLOC(uint8_t, LDNS_SHA256_DIGEST_LENGTH);
		if (!digest) {
			ldns_rr_free(ds);
			return NULL;
		}
		break;
	case LDNS_HASH_GOST:
#ifdef USE_GOST
		(void)ldns_key_EVP_load_gost_id();
		md = EVP_get_digestbyname("md_gost94");
		if(!md) {
			ldns_rr_free(ds);
			return NULL;
		}
		digest = LDNS_XMALLOC(uint8_t, EVP_MD_size(md));
		if (!digest) {
			ldns_rr_free(ds);
			return NULL;
		}
                break;
#else
		/* not implemented */
		ldns_rr_free(ds);
		return NULL;
#endif
	case LDNS_SHA384:
#ifdef USE_ECDSA
		digest = LDNS_XMALLOC(uint8_t, SHA384_DIGEST_LENGTH);
		if (!digest) {
			ldns_rr_free(ds);
			return NULL;
		}
                break;
#else
		/* not implemented */
		ldns_rr_free(ds);
		return NULL;
#endif
	}

	data_buf = ldns_buffer_new(LDNS_MAX_PACKETLEN);
	if (!data_buf) {
		LDNS_FREE(digest);
		ldns_rr_free(ds);
		return NULL;
	}

	/* keytag */
	keytag = htons(ldns_calc_keytag((ldns_rr*)key));
	tmp = ldns_rdf_new_frm_data(LDNS_RDF_TYPE_INT16,
						   sizeof(uint16_t),
						   &keytag);
	ldns_rr_push_rdf(ds, tmp);

	/* copy the algorithm field */
	if ((tmp = ldns_rr_rdf(key, 2)) == NULL) {
		LDNS_FREE(digest);
		ldns_buffer_free(data_buf);
		ldns_rr_free(ds);
		return NULL;
	} else {
		ldns_rr_push_rdf(ds, ldns_rdf_clone( tmp ));
	}

	/* digest hash type */
	sha1hash = (uint8_t)h;
	tmp = ldns_rdf_new_frm_data(LDNS_RDF_TYPE_INT8,
						   sizeof(uint8_t),
						   &sha1hash);
	ldns_rr_push_rdf(ds, tmp);

	/* digest */
	/* owner name */
	tmp = ldns_rdf_clone(ldns_rr_owner(key));
	ldns_dname2canonical(tmp);
	if (ldns_rdf2buffer_wire(data_buf, tmp) != LDNS_STATUS_OK) {
		LDNS_FREE(digest);
		ldns_buffer_free(data_buf);
		ldns_rr_free(ds);
		ldns_rdf_deep_free(tmp);
		return NULL;
	}
	ldns_rdf_deep_free(tmp);

	/* all the rdata's */
	if (ldns_rr_rdata2buffer_wire(data_buf,
							(ldns_rr*)key) != LDNS_STATUS_OK) {
		LDNS_FREE(digest);
		ldns_buffer_free(data_buf);
		ldns_rr_free(ds);
		return NULL;
	}
	switch(h) {
	case LDNS_SHA1:
		(void) ldns_sha1((unsigned char *) ldns_buffer_begin(data_buf),
		                 (unsigned int) ldns_buffer_position(data_buf),
		                 (unsigned char *) digest);

		tmp = ldns_rdf_new_frm_data(LDNS_RDF_TYPE_HEX,
		                            LDNS_SHA1_DIGEST_LENGTH,
		                            digest);
		ldns_rr_push_rdf(ds, tmp);

		break;
	case LDNS_SHA256:
		(void) ldns_sha256((unsigned char *) ldns_buffer_begin(data_buf),
		                   (unsigned int) ldns_buffer_position(data_buf),
		                   (unsigned char *) digest);
		tmp = ldns_rdf_new_frm_data(LDNS_RDF_TYPE_HEX,
		                            LDNS_SHA256_DIGEST_LENGTH,
		                            digest);
		ldns_rr_push_rdf(ds, tmp);
		break;
	case LDNS_HASH_GOST:
#ifdef USE_GOST
		if(!ldns_digest_evp((unsigned char *) ldns_buffer_begin(data_buf),
				(unsigned int) ldns_buffer_position(data_buf),
				(unsigned char *) digest, md)) {
			LDNS_FREE(digest);
			ldns_buffer_free(data_buf);
			ldns_rr_free(ds);
			return NULL;
		}
		tmp = ldns_rdf_new_frm_data(LDNS_RDF_TYPE_HEX,
		                            (size_t)EVP_MD_size(md),
		                            digest);
		ldns_rr_push_rdf(ds, tmp);
#endif
		break;
	case LDNS_SHA384:
#ifdef USE_ECDSA
		(void) SHA384((unsigned char *) ldns_buffer_begin(data_buf),
		                 (unsigned int) ldns_buffer_position(data_buf),
		                 (unsigned char *) digest);
		tmp = ldns_rdf_new_frm_data(LDNS_RDF_TYPE_HEX,
		                            SHA384_DIGEST_LENGTH,
		                            digest);
		ldns_rr_push_rdf(ds, tmp);
#endif
		break;
	}

	LDNS_FREE(digest);
	ldns_buffer_free(data_buf);
	return ds;
}

/* From RFC3845:
 *
 * 2.1.2.  The List of Type Bit Map(s) Field
 *
 *    The RR type space is split into 256 window blocks, each representing
 *    the low-order 8 bits of the 16-bit RR type space.  Each block that
 *    has at least one active RR type is encoded using a single octet
 *    window number (from 0 to 255), a single octet bitmap length (from 1
 *    to 32) indicating the number of octets used for the window block's
 *    bitmap, and up to 32 octets (256 bits) of bitmap.
 *
 *    Window blocks are present in the NSEC RR RDATA in increasing
 *    numerical order.
 *
 *    "|" denotes concatenation
 *
 *    Type Bit Map(s) Field = ( Window Block # | Bitmap Length | Bitmap ) +
 *
 *    <cut>
 *
 *    Blocks with no types present MUST NOT be included.  Trailing zero
 *    octets in the bitmap MUST be omitted.  The length of each block's
 *    bitmap is determined by the type code with the largest numerical
 *    value within that block, among the set of RR types present at the
 *    NSEC RR's owner name.  Trailing zero octets not specified MUST be
 *    interpreted as zero octets.
 */
ldns_rdf *
ldns_dnssec_create_nsec_bitmap(ldns_rr_type rr_type_list[],
                               size_t size,
                               ldns_rr_type nsec_type)
{
	uint8_t  window;		/*  most significant octet of type */
	uint8_t  subtype;		/* least significant octet of type */
	uint16_t windows[256]		/* Max subtype per window */
#ifndef S_SPLINT_S
	                      = { 0 }	/* Initialize ALL elements with 0 */
#endif
	                             ;
	ldns_rr_type* d;	/* used to traverse rr_type_list*/
	size_t i;		/* used to traverse windows array */

	size_t sz;			/* size needed for type bitmap rdf */
	uint8_t* data = NULL;		/* rdf data */
	uint8_t* dptr;			/* used to itraverse rdf data */
	ldns_rdf* rdf;			/* bitmap rdf to return */

	if (nsec_type != LDNS_RR_TYPE_NSEC &&
	    nsec_type != LDNS_RR_TYPE_NSEC3) {
		return NULL;
	}

	/* Which other windows need to be in the bitmap rdf?
	 */
	for (d = rr_type_list; d < rr_type_list + size; d++) {
		window  = *d >> 8;
		subtype = *d & 0xff;
		if (windows[window] < subtype) {
			windows[window] = subtype;
		}
	}

	/* How much space do we need in the rdf for those windows?
	 */
	sz = 0;
	for (i = 0; i < 256; i++) {
		if (windows[i]) {
			sz += windows[i] / 8 + 3;
		}
	}
	if (sz > 0) {
		/* Format rdf data according RFC3845 Section 2.1.2 (see above)
		 */
		dptr = data = LDNS_CALLOC(uint8_t, sz);
		if (!data) {
			return NULL;
		}
		for (i = 0; i < 256; i++) {
			if (windows[i]) {
				*dptr++ = (uint8_t)i;
				*dptr++ = (uint8_t)(windows[i] / 8 + 1);

				/* Now let windows[i] index the bitmap
				 * within data
				 */
				windows[i] = (uint16_t)(dptr - data);

				dptr += dptr[-1];
			}
		}
	}

	/* Set the bits?
	 */
	for (d = rr_type_list; d < rr_type_list + size; d++) {
		subtype = *d & 0xff;
		data[windows[*d >> 8] + subtype/8] |= (0x80 >> (subtype % 8));
	}

	/* Allocate and return rdf structure for the data
	 */
	rdf = ldns_rdf_new(LDNS_RDF_TYPE_BITMAP, sz, data);
	if (!rdf) {
		LDNS_FREE(data);
		return NULL;
	}
	return rdf;
}

int
ldns_dnssec_rrsets_contains_type(ldns_dnssec_rrsets *rrsets,
                                 ldns_rr_type type)
{
	ldns_dnssec_rrsets *cur_rrset = rrsets;
	while (cur_rrset) {
		if (cur_rrset->type == type) {
			return 1;
		}
		cur_rrset = cur_rrset->next;
	}
	return 0;
}

ldns_rr *
ldns_dnssec_create_nsec(ldns_dnssec_name *from,
                        ldns_dnssec_name *to,
                        ldns_rr_type nsec_type)
{
	ldns_rr *nsec_rr;
	ldns_rr_type types[65536];
	size_t type_count = 0;
	ldns_dnssec_rrsets *cur_rrsets;
	int on_delegation_point;

	if (!from || !to || (nsec_type != LDNS_RR_TYPE_NSEC)) {
		return NULL;
	}

	nsec_rr = ldns_rr_new();
	ldns_rr_set_type(nsec_rr, nsec_type);
	ldns_rr_set_owner(nsec_rr, ldns_rdf_clone(ldns_dnssec_name_name(from)));
	ldns_rr_push_rdf(nsec_rr, ldns_rdf_clone(ldns_dnssec_name_name(to)));

	on_delegation_point = ldns_dnssec_rrsets_contains_type(
			from->rrsets, LDNS_RR_TYPE_NS)
		&& !ldns_dnssec_rrsets_contains_type(
			from->rrsets, LDNS_RR_TYPE_SOA);

	cur_rrsets = from->rrsets;
	while (cur_rrsets) {
		/* Do not include non-authoritative rrsets on the delegation point
		 * in the type bitmap */
		if ((on_delegation_point && (
				cur_rrsets->type == LDNS_RR_TYPE_NS
			     || cur_rrsets->type == LDNS_RR_TYPE_DS))
			|| (!on_delegation_point &&
				cur_rrsets->type != LDNS_RR_TYPE_RRSIG
			     && cur_rrsets->type != LDNS_RR_TYPE_NSEC)) {

			types[type_count] = cur_rrsets->type;
			type_count++;
		}
		cur_rrsets = cur_rrsets->next;

	}
	types[type_count] = LDNS_RR_TYPE_RRSIG;
	type_count++;
	types[type_count] = LDNS_RR_TYPE_NSEC;
	type_count++;

	ldns_rr_push_rdf(nsec_rr, ldns_dnssec_create_nsec_bitmap(types,
	                               type_count,
	                               nsec_type));

	return nsec_rr;
}

ldns_rr *
ldns_dnssec_create_nsec3(ldns_dnssec_name *from,
					ldns_dnssec_name *to,
					ldns_rdf *zone_name,
					uint8_t algorithm,
					uint8_t flags,
					uint16_t iterations,
					uint8_t salt_length,
					uint8_t *salt)
{
	ldns_rr *nsec_rr;
	ldns_rr_type types[65536];
	size_t type_count = 0;
	ldns_dnssec_rrsets *cur_rrsets;
	ldns_status status;
	int on_delegation_point;

	if (!from) {
		return NULL;
	}

	nsec_rr = ldns_rr_new_frm_type(LDNS_RR_TYPE_NSEC3);
	ldns_rr_set_owner(nsec_rr,
	                  ldns_nsec3_hash_name(ldns_dnssec_name_name(from),
	                  algorithm,
	                  iterations,
	                  salt_length,
	                  salt));
	status = ldns_dname_cat(ldns_rr_owner(nsec_rr), zone_name);
        if(status != LDNS_STATUS_OK) {
                ldns_rr_free(nsec_rr);
                return NULL;
        }
	ldns_nsec3_add_param_rdfs(nsec_rr,
	                          algorithm,
	                          flags,
	                          iterations,
	                          salt_length,
	                          salt);

	on_delegation_point = ldns_dnssec_rrsets_contains_type(
			from->rrsets, LDNS_RR_TYPE_NS)
		&& !ldns_dnssec_rrsets_contains_type(
			from->rrsets, LDNS_RR_TYPE_SOA);
	cur_rrsets = from->rrsets;
	while (cur_rrsets) {
		/* Do not include non-authoritative rrsets on the delegation point
		 * in the type bitmap. Potentionally not skipping insecure
		 * delegation should have been done earlier, in function
		 * ldns_dnssec_zone_create_nsec3s, or even earlier in:
		 * ldns_dnssec_zone_sign_nsec3_flg .
		 */
		if ((on_delegation_point && (
				cur_rrsets->type == LDNS_RR_TYPE_NS
			     || cur_rrsets->type == LDNS_RR_TYPE_DS))
			|| (!on_delegation_point &&
				cur_rrsets->type != LDNS_RR_TYPE_RRSIG)) {

			types[type_count] = cur_rrsets->type;
			type_count++;
		}
		cur_rrsets = cur_rrsets->next;
	}
	/* always add rrsig type if this is not an unsigned
	 * delegation
	 */
	if (type_count > 0 &&
	    !(type_count == 1 && types[0] == LDNS_RR_TYPE_NS)) {
		types[type_count] = LDNS_RR_TYPE_RRSIG;
		type_count++;
	}

	/* leave next rdata empty if they weren't precomputed yet */
	if (to && to->hashed_name) {
		(void) ldns_rr_set_rdf(nsec_rr,
		                       ldns_rdf_clone(to->hashed_name),
		                       4);
	} else {
		(void) ldns_rr_set_rdf(nsec_rr, NULL, 4);
	}

	ldns_rr_push_rdf(nsec_rr,
	                 ldns_dnssec_create_nsec_bitmap(types,
	                 type_count,
	                 LDNS_RR_TYPE_NSEC3));

	return nsec_rr;
}

ldns_rr *
ldns_create_nsec(ldns_rdf *cur_owner, ldns_rdf *next_owner, ldns_rr_list *rrs)
{
	/* we do not do any check here - garbage in, garbage out */

	/* the the start and end names - get the type from the
	 * before rrlist */

	/* inefficient, just give it a name, a next name, and a list of rrs */
	/* we make 1 big uberbitmap first, then windows */
	/* todo: make something more efficient :) */
	uint16_t i;
	ldns_rr *i_rr;
	uint16_t i_type;

	ldns_rr *nsec = NULL;
	ldns_rr_type i_type_list[65536];
	size_t type_count = 0;

	nsec = ldns_rr_new();
	ldns_rr_set_type(nsec, LDNS_RR_TYPE_NSEC);
	ldns_rr_set_owner(nsec, ldns_rdf_clone(cur_owner));
	ldns_rr_push_rdf(nsec, ldns_rdf_clone(next_owner));

	for (i = 0; i < ldns_rr_list_rr_count(rrs); i++) {
		i_rr = ldns_rr_list_rr(rrs, i);
		if (ldns_rdf_compare(cur_owner,
						 ldns_rr_owner(i_rr)) == 0) {
			i_type = ldns_rr_get_type(i_rr);
			if (i_type != LDNS_RR_TYPE_RRSIG && i_type != LDNS_RR_TYPE_NSEC) {
				if (type_count == 0 || i_type_list[type_count-1] != i_type) {
					i_type_list[type_count] = i_type;
					type_count++;
				}
			}
		}
	}

	i_type_list[type_count] = LDNS_RR_TYPE_RRSIG;
	type_count++;
	i_type_list[type_count] = LDNS_RR_TYPE_NSEC;
	type_count++;

	ldns_rr_push_rdf(nsec,
				  ldns_dnssec_create_nsec_bitmap(i_type_list,
						type_count, LDNS_RR_TYPE_NSEC));

	return nsec;
}

ldns_rdf *
ldns_nsec3_hash_name(ldns_rdf *name,
				 uint8_t algorithm,
				 uint16_t iterations,
				 uint8_t salt_length,
				 uint8_t *salt)
{
	size_t hashed_owner_str_len;
	ldns_rdf *cann;
	ldns_rdf *hashed_owner;
	unsigned char *hashed_owner_str;
	char *hashed_owner_b32;
	size_t hashed_owner_b32_len;
	uint32_t cur_it;
	/* define to contain the largest possible hash, which is
	 * sha1 at the moment */
	unsigned char hash[LDNS_SHA1_DIGEST_LENGTH];
	ldns_status status;

	/* TODO: mnemonic list for hash algs SHA-1, default to 1 now (sha1) */
	if (algorithm != LDNS_SHA1) {
		return NULL;
	}

	/* prepare the owner name according to the draft section bla */
	cann = ldns_rdf_clone(name);
	if(!cann) {
#ifdef STDERR_MSGS
		fprintf(stderr, "Memory error\n");
#endif
		return NULL;
	}
	ldns_dname2canonical(cann);

	hashed_owner_str_len = salt_length + ldns_rdf_size(cann);
	hashed_owner_str = LDNS_XMALLOC(unsigned char, hashed_owner_str_len);
        if(!hashed_owner_str) {
	        ldns_rdf_deep_free(cann);
                return NULL;
        }
	memcpy(hashed_owner_str, ldns_rdf_data(cann), ldns_rdf_size(cann));
	memcpy(hashed_owner_str + ldns_rdf_size(cann), salt, salt_length);
	ldns_rdf_deep_free(cann);

	for (cur_it = iterations + 1; cur_it > 0; cur_it--) {
		(void) ldns_sha1((unsigned char *) hashed_owner_str,
		                 (unsigned int) hashed_owner_str_len, hash);

		LDNS_FREE(hashed_owner_str);
		hashed_owner_str_len = salt_length + LDNS_SHA1_DIGEST_LENGTH;
		hashed_owner_str = LDNS_XMALLOC(unsigned char, hashed_owner_str_len);
		if (!hashed_owner_str) {
			return NULL;
		}
		memcpy(hashed_owner_str, hash, LDNS_SHA1_DIGEST_LENGTH);
		memcpy(hashed_owner_str + LDNS_SHA1_DIGEST_LENGTH, salt, salt_length);
		hashed_owner_str_len = LDNS_SHA1_DIGEST_LENGTH + salt_length;
	}

	LDNS_FREE(hashed_owner_str);
	hashed_owner_str = hash;
	hashed_owner_str_len = LDNS_SHA1_DIGEST_LENGTH;

	hashed_owner_b32 = LDNS_XMALLOC(char,
                  ldns_b32_ntop_calculate_size(hashed_owner_str_len) + 1);
        if(!hashed_owner_b32) {
                return NULL;
        }
        hashed_owner_b32_len = (size_t) ldns_b32_ntop_extended_hex(
                (uint8_t *) hashed_owner_str,
                hashed_owner_str_len,
                hashed_owner_b32,
                ldns_b32_ntop_calculate_size(hashed_owner_str_len)+1);
	if (hashed_owner_b32_len < 1) {
#ifdef STDERR_MSGS
		fprintf(stderr, "Error in base32 extended hex encoding ");
		fprintf(stderr, "of hashed owner name (name: ");
		ldns_rdf_print(stderr, name);
		fprintf(stderr, ", return code: %u)\n",
		        (unsigned int) hashed_owner_b32_len);
#endif
		LDNS_FREE(hashed_owner_b32);
		return NULL;
	}
	hashed_owner_b32[hashed_owner_b32_len] = '\0';

	status = ldns_str2rdf_dname(&hashed_owner, hashed_owner_b32);
	if (status != LDNS_STATUS_OK) {
#ifdef STDERR_MSGS
		fprintf(stderr, "Error creating rdf from %s\n", hashed_owner_b32);
#endif
		LDNS_FREE(hashed_owner_b32);
		return NULL;
	}

	LDNS_FREE(hashed_owner_b32);
	return hashed_owner;
}

void
ldns_nsec3_add_param_rdfs(ldns_rr *rr,
					 uint8_t algorithm,
					 uint8_t flags,
					 uint16_t iterations,
					 uint8_t salt_length,
					 uint8_t *salt)
{
	ldns_rdf *salt_rdf = NULL;
	uint8_t *salt_data = NULL;
	ldns_rdf *old;

	old = ldns_rr_set_rdf(rr,
	                      ldns_rdf_new_frm_data(LDNS_RDF_TYPE_INT8,
	                                            1, (void*)&algorithm),
	                      0);
	if (old) ldns_rdf_deep_free(old);

	old = ldns_rr_set_rdf(rr,
	                      ldns_rdf_new_frm_data(LDNS_RDF_TYPE_INT8,
	                                            1, (void*)&flags),
	                      1);
	if (old) ldns_rdf_deep_free(old);

	old = ldns_rr_set_rdf(rr,
                          ldns_native2rdf_int16(LDNS_RDF_TYPE_INT16,
                                                iterations),
	                      2);
	if (old) ldns_rdf_deep_free(old);

	salt_data = LDNS_XMALLOC(uint8_t, salt_length + 1);
        if(!salt_data) {
                /* no way to return error */
                return;
        }
	salt_data[0] = salt_length;
	memcpy(salt_data + 1, salt, salt_length);
	salt_rdf = ldns_rdf_new_frm_data(LDNS_RDF_TYPE_NSEC3_SALT,
							   salt_length + 1,
							   salt_data);
        if(!salt_rdf) {
                LDNS_FREE(salt_data);
                /* no way to return error */
                return;
        }

	old = ldns_rr_set_rdf(rr, salt_rdf, 3);
	if (old) ldns_rdf_deep_free(old);
	LDNS_FREE(salt_data);
}

static int
rr_list_delegation_only(ldns_rdf *origin, ldns_rr_list *rr_list)
{
	size_t i;
	ldns_rr *cur_rr;
	if (!origin || !rr_list) return 0;
	for (i = 0; i < ldns_rr_list_rr_count(rr_list); i++) {
		cur_rr = ldns_rr_list_rr(rr_list, i);
		if (ldns_dname_compare(ldns_rr_owner(cur_rr), origin) == 0) {
			return 0;
		}
		if (ldns_rr_get_type(cur_rr) != LDNS_RR_TYPE_NS) {
			return 0;
		}
	}
	return 1;
}

/* this will NOT return the NSEC3  completed, you will have to run the
   finalize function on the rrlist later! */
ldns_rr *
ldns_create_nsec3(ldns_rdf *cur_owner,
                  ldns_rdf *cur_zone,
                  ldns_rr_list *rrs,
                  uint8_t algorithm,
                  uint8_t flags,
                  uint16_t iterations,
                  uint8_t salt_length,
                  uint8_t *salt,
                  bool emptynonterminal)
{
	size_t i;
	ldns_rr *i_rr;
	uint16_t i_type;

	ldns_rr *nsec = NULL;
	ldns_rdf *hashed_owner = NULL;

	ldns_status status;

    ldns_rr_type i_type_list[1024];
	size_t type_count = 0;

	hashed_owner = ldns_nsec3_hash_name(cur_owner,
								 algorithm,
								 iterations,
								 salt_length,
								 salt);
	status = ldns_dname_cat(hashed_owner, cur_zone);
        if(status != LDNS_STATUS_OK) {
		ldns_rdf_deep_free(hashed_owner);
                return NULL;
	}
	nsec = ldns_rr_new_frm_type(LDNS_RR_TYPE_NSEC3);
        if(!nsec) {
		ldns_rdf_deep_free(hashed_owner);
                return NULL;
	}
	ldns_rr_set_type(nsec, LDNS_RR_TYPE_NSEC3);
	ldns_rr_set_owner(nsec, hashed_owner);

	ldns_nsec3_add_param_rdfs(nsec,
						 algorithm,
						 flags,
						 iterations,
						 salt_length,
						 salt);
	(void) ldns_rr_set_rdf(nsec, NULL, 4);


	for (i = 0; i < ldns_rr_list_rr_count(rrs); i++) {
		i_rr = ldns_rr_list_rr(rrs, i);
		if (ldns_rdf_compare(cur_owner,
						 ldns_rr_owner(i_rr)) == 0) {
			i_type = ldns_rr_get_type(i_rr);
			if (type_count == 0 || i_type_list[type_count-1] != i_type) {
				i_type_list[type_count] = i_type;
				type_count++;
			}
		}
	}

	/* add RRSIG anyway, but only if this is not an ENT or
	 * an unsigned delegation */
	if (!emptynonterminal && !rr_list_delegation_only(cur_zone, rrs)) {
		i_type_list[type_count] = LDNS_RR_TYPE_RRSIG;
		type_count++;
	}

	/* and SOA if owner == zone */
	if (ldns_dname_compare(cur_zone, cur_owner) == 0) {
		i_type_list[type_count] = LDNS_RR_TYPE_SOA;
		type_count++;
	}

	ldns_rr_push_rdf(nsec,
				  ldns_dnssec_create_nsec_bitmap(i_type_list,
						type_count, LDNS_RR_TYPE_NSEC3));

	return nsec;
}

uint8_t
ldns_nsec3_algorithm(const ldns_rr *nsec3_rr)
{
	if (nsec3_rr &&
	      (ldns_rr_get_type(nsec3_rr) == LDNS_RR_TYPE_NSEC3 ||
	       ldns_rr_get_type(nsec3_rr) == LDNS_RR_TYPE_NSEC3PARAM)
	    && (ldns_rr_rdf(nsec3_rr, 0) != NULL)
	    && ldns_rdf_size(ldns_rr_rdf(nsec3_rr, 0)) > 0) {
		return ldns_rdf2native_int8(ldns_rr_rdf(nsec3_rr, 0));
	}
	return 0;
}

uint8_t
ldns_nsec3_flags(const ldns_rr *nsec3_rr)
{
	if (nsec3_rr &&
	      (ldns_rr_get_type(nsec3_rr) == LDNS_RR_TYPE_NSEC3 ||
	       ldns_rr_get_type(nsec3_rr) == LDNS_RR_TYPE_NSEC3PARAM)
	    && (ldns_rr_rdf(nsec3_rr, 1) != NULL)
	    && ldns_rdf_size(ldns_rr_rdf(nsec3_rr, 1)) > 0) {
		return ldns_rdf2native_int8(ldns_rr_rdf(nsec3_rr, 1));
	}
	return 0;
}

bool
ldns_nsec3_optout(const ldns_rr *nsec3_rr)
{
	return (ldns_nsec3_flags(nsec3_rr) & LDNS_NSEC3_VARS_OPTOUT_MASK);
}

uint16_t
ldns_nsec3_iterations(const ldns_rr *nsec3_rr)
{
	if (nsec3_rr &&
	      (ldns_rr_get_type(nsec3_rr) == LDNS_RR_TYPE_NSEC3 ||
	       ldns_rr_get_type(nsec3_rr) == LDNS_RR_TYPE_NSEC3PARAM)
	    && (ldns_rr_rdf(nsec3_rr, 2) != NULL)
	    && ldns_rdf_size(ldns_rr_rdf(nsec3_rr, 2)) > 0) {
		return ldns_rdf2native_int16(ldns_rr_rdf(nsec3_rr, 2));
	}
	return 0;

}

ldns_rdf *
ldns_nsec3_salt(const ldns_rr *nsec3_rr)
{
	if (nsec3_rr &&
	      (ldns_rr_get_type(nsec3_rr) == LDNS_RR_TYPE_NSEC3 ||
	       ldns_rr_get_type(nsec3_rr) == LDNS_RR_TYPE_NSEC3PARAM)
	    ) {
		return ldns_rr_rdf(nsec3_rr, 3);
	}
	return NULL;
}

uint8_t
ldns_nsec3_salt_length(const ldns_rr *nsec3_rr)
{
	ldns_rdf *salt_rdf = ldns_nsec3_salt(nsec3_rr);
	if (salt_rdf && ldns_rdf_size(salt_rdf) > 0) {
		return (uint8_t) ldns_rdf_data(salt_rdf)[0];
	}
	return 0;
}

/* allocs data, free with LDNS_FREE() */
uint8_t *
ldns_nsec3_salt_data(const ldns_rr *nsec3_rr)
{
	uint8_t salt_length;
	uint8_t *salt;

	ldns_rdf *salt_rdf = ldns_nsec3_salt(nsec3_rr);
	if (salt_rdf && ldns_rdf_size(salt_rdf) > 0) {
	    	salt_length = ldns_rdf_data(salt_rdf)[0];
		salt = LDNS_XMALLOC(uint8_t, salt_length);
                if(!salt) return NULL;
		memcpy(salt, &ldns_rdf_data(salt_rdf)[1], salt_length);
		return salt;
	}
	return NULL;
}

ldns_rdf *
ldns_nsec3_next_owner(const ldns_rr *nsec3_rr)
{
	if (!nsec3_rr || ldns_rr_get_type(nsec3_rr) != LDNS_RR_TYPE_NSEC3) {
		return NULL;
	} else {
		return ldns_rr_rdf(nsec3_rr, 4);
	}
}

ldns_rdf *
ldns_nsec3_bitmap(const ldns_rr *nsec3_rr)
{
	if (!nsec3_rr || ldns_rr_get_type(nsec3_rr) != LDNS_RR_TYPE_NSEC3) {
		return NULL;
	} else {
		return ldns_rr_rdf(nsec3_rr, 5);
	}
}

ldns_rdf *
ldns_nsec3_hash_name_frm_nsec3(const ldns_rr *nsec, ldns_rdf *name)
{
	uint8_t algorithm;
	uint16_t iterations;
	uint8_t salt_length;
	uint8_t *salt = 0;

	ldns_rdf *hashed_owner;

	algorithm = ldns_nsec3_algorithm(nsec);
	salt_length = ldns_nsec3_salt_length(nsec);
	salt = ldns_nsec3_salt_data(nsec);
	iterations = ldns_nsec3_iterations(nsec);

	hashed_owner = ldns_nsec3_hash_name(name,
								 algorithm,
								 iterations,
								 salt_length,
								 salt);

	LDNS_FREE(salt);
	return hashed_owner;
}

bool
ldns_nsec_bitmap_covers_type(const  ldns_rdf* bitmap, ldns_rr_type type)
{
	uint8_t* dptr;
	uint8_t* dend;

	/* From RFC3845 Section 2.1.2:
	 *
	 *	"The RR type space is split into 256 window blocks, each re-
	 *	 presenting the low-order 8 bits of the 16-bit RR type space."
	 */
	uint8_t  window = type >> 8;
	uint8_t subtype = type & 0xff;

	if (! bitmap) {
		return false;
	}
	assert(ldns_rdf_get_type(bitmap) == LDNS_RDF_TYPE_BITMAP);

	dptr = ldns_rdf_data(bitmap);
	dend = ldns_rdf_data(bitmap) + ldns_rdf_size(bitmap);

	/* Type Bitmap = ( Window Block # | Bitmap Length | Bitmap ) +
	 *                 dptr[0]          dptr[1]         dptr[2:]
	 */
	while (dptr < dend && dptr[0] <= window) {

		if (dptr[0] == window && subtype / 8 < dptr[1] &&
				dptr + dptr[1] + 2 <= dend) {

			return dptr[2 + subtype / 8] & (0x80 >> (subtype % 8));
		}
		dptr += dptr[1] + 2; /* next window */
	}
	return false;
}

ldns_status
ldns_nsec_bitmap_set_type(ldns_rdf* bitmap, ldns_rr_type type)
{
	uint8_t* dptr;
	uint8_t* dend;

	/* From RFC3845 Section 2.1.2:
	 *
	 *	"The RR type space is split into 256 window blocks, each re-
	 *	 presenting the low-order 8 bits of the 16-bit RR type space."
	 */
	uint8_t  window = type >> 8;
	uint8_t subtype = type & 0xff;

	if (! bitmap) {
		return false;
	}
	assert(ldns_rdf_get_type(bitmap) == LDNS_RDF_TYPE_BITMAP);

	dptr = ldns_rdf_data(bitmap);
	dend = ldns_rdf_data(bitmap) + ldns_rdf_size(bitmap);

	/* Type Bitmap = ( Window Block # | Bitmap Length | Bitmap ) +
	 *                 dptr[0]          dptr[1]         dptr[2:]
	 */
	while (dptr < dend && dptr[0] <= window) {

		if (dptr[0] == window && subtype / 8 < dptr[1] &&
				dptr + dptr[1] + 2 <= dend) {

			dptr[2 + subtype / 8] |= (0x80 >> (subtype % 8));
			return LDNS_STATUS_OK;
		}
		dptr += dptr[1] + 2; /* next window */
	}
	return LDNS_STATUS_TYPE_NOT_IN_BITMAP;
}

ldns_status
ldns_nsec_bitmap_clear_type(ldns_rdf* bitmap, ldns_rr_type type)
{
	uint8_t* dptr;
	uint8_t* dend;

	/* From RFC3845 Section 2.1.2:
	 *
	 *	"The RR type space is split into 256 window blocks, each re-
	 *	 presenting the low-order 8 bits of the 16-bit RR type space."
	 */
	uint8_t  window = type >> 8;
	uint8_t subtype = type & 0xff;

	if (! bitmap) {
		return false;
	}

	assert(ldns_rdf_get_type(bitmap) == LDNS_RDF_TYPE_BITMAP);

	dptr = ldns_rdf_data(bitmap);
	dend = ldns_rdf_data(bitmap) + ldns_rdf_size(bitmap);

	/* Type Bitmap = ( Window Block # | Bitmap Length | Bitmap ) +
	 *                 dptr[0]          dptr[1]         dptr[2:]
	 */
	while (dptr < dend && dptr[0] <= window) {

		if (dptr[0] == window && subtype / 8 < dptr[1] &&
				dptr + dptr[1] + 2 <= dend) {

			dptr[2 + subtype / 8] &= ~(0x80 >> (subtype % 8));
			return LDNS_STATUS_OK;
		}
		dptr += dptr[1] + 2; /* next window */
	}
	return LDNS_STATUS_TYPE_NOT_IN_BITMAP;
}


bool
ldns_nsec_covers_name(const ldns_rr *nsec, const ldns_rdf *name)
{
	ldns_rdf *nsec_owner = ldns_rr_owner(nsec);
	ldns_rdf *hash_next;
	char *next_hash_str;
	ldns_rdf *nsec_next = NULL;
	ldns_status status;
	ldns_rdf *chopped_dname;
	bool result;

	if (ldns_rr_get_type(nsec) == LDNS_RR_TYPE_NSEC) {
		if (ldns_rr_rdf(nsec, 0) != NULL) {
			nsec_next = ldns_rdf_clone(ldns_rr_rdf(nsec, 0));
		} else {
			return false;
		}
	} else if (ldns_rr_get_type(nsec) == LDNS_RR_TYPE_NSEC3) {
		hash_next = ldns_nsec3_next_owner(nsec);
		next_hash_str = ldns_rdf2str(hash_next);
		nsec_next = ldns_dname_new_frm_str(next_hash_str);
		LDNS_FREE(next_hash_str);
		chopped_dname = ldns_dname_left_chop(nsec_owner);
		status = ldns_dname_cat(nsec_next, chopped_dname);
		ldns_rdf_deep_free(chopped_dname);
		if (status != LDNS_STATUS_OK) {
			printf("error catting: %s\n", ldns_get_errorstr_by_id(status));
		}
	} else {
		ldns_rdf_deep_free(nsec_next);
		return false;
	}

	/* in the case of the last nsec */
	if(ldns_dname_compare(nsec_owner, nsec_next) > 0) {
		result = (ldns_dname_compare(nsec_owner, name) <= 0 ||
				ldns_dname_compare(name, nsec_next) < 0);
	} else if(ldns_dname_compare(nsec_owner, nsec_next) < 0) {
		result = (ldns_dname_compare(nsec_owner, name) <= 0 &&
		          ldns_dname_compare(name, nsec_next) < 0);
	} else {
		result = true;
	}

	ldns_rdf_deep_free(nsec_next);
	return result;
}

#ifdef HAVE_SSL
/* sig may be null - if so look in the packet */

ldns_status
ldns_pkt_verify_time(ldns_pkt *p, ldns_rr_type t, ldns_rdf *o,
		ldns_rr_list *k, ldns_rr_list *s,
		time_t check_time, ldns_rr_list *good_keys)
{
	ldns_rr_list *rrset;
	ldns_rr_list *sigs;
	ldns_rr_list *sigs_covered;
	ldns_rdf *rdf_t;
	ldns_rr_type t_netorder;

	if (!k) {
		return LDNS_STATUS_ERR;
		/* return LDNS_STATUS_CRYPTO_NO_DNSKEY; */
	}

	if (t == LDNS_RR_TYPE_RRSIG) {
		/* we don't have RRSIG(RRSIG) (yet? ;-) ) */
		return LDNS_STATUS_ERR;
	}

	if (s) {
		/* if s is not NULL, the sigs are given to use */
		sigs = s;
	} else {
		/* otherwise get them from the packet */
		sigs = ldns_pkt_rr_list_by_name_and_type(p, o,
				LDNS_RR_TYPE_RRSIG,
				LDNS_SECTION_ANY_NOQUESTION);
		if (!sigs) {
			/* no sigs */
			return LDNS_STATUS_ERR;
			/* return LDNS_STATUS_CRYPTO_NO_RRSIG; */
		}
	}

	/* rrsig are subtyped, so now we need to find the correct
	 * sigs for the type t
	 */
	t_netorder = htons(t); /* rdf are in network order! */
	/* a type identifier is a 16-bit number, so the size is 2 bytes */
	rdf_t = ldns_rdf_new(LDNS_RDF_TYPE_TYPE, 2, &t_netorder);

	sigs_covered = ldns_rr_list_subtype_by_rdf(sigs, rdf_t, 0);
	ldns_rdf_free(rdf_t);
	if (! sigs_covered) {
		if (! s) {
			ldns_rr_list_deep_free(sigs);
		}
		return LDNS_STATUS_ERR;
	}
	ldns_rr_list_deep_free(sigs_covered);

	rrset = ldns_pkt_rr_list_by_name_and_type(p, o, t,
			LDNS_SECTION_ANY_NOQUESTION);
	if (!rrset) {
		if (! s) {
			ldns_rr_list_deep_free(sigs);
		}
		return LDNS_STATUS_ERR;
	}
	return ldns_verify_time(rrset, sigs, k, check_time, good_keys);
}

ldns_status
ldns_pkt_verify(ldns_pkt *p, ldns_rr_type t, ldns_rdf *o,
		ldns_rr_list *k, ldns_rr_list *s, ldns_rr_list *good_keys)
{
	return ldns_pkt_verify_time(p, t, o, k, s, ldns_time(NULL), good_keys);
}
#endif /* HAVE_SSL */

ldns_status
ldns_dnssec_chain_nsec3_list(ldns_rr_list *nsec3_rrs)
{
	size_t i;
	char *next_nsec_owner_str;
	ldns_rdf *next_nsec_owner_label;
	ldns_rdf *next_nsec_rdf;
	ldns_status status = LDNS_STATUS_OK;

	for (i = 0; i < ldns_rr_list_rr_count(nsec3_rrs); i++) {
		if (i == ldns_rr_list_rr_count(nsec3_rrs) - 1) {
			next_nsec_owner_label =
				ldns_dname_label(ldns_rr_owner(ldns_rr_list_rr(nsec3_rrs,
													  0)), 0);
			next_nsec_owner_str = ldns_rdf2str(next_nsec_owner_label);
			if (next_nsec_owner_str[strlen(next_nsec_owner_str) - 1]
			    == '.') {
				next_nsec_owner_str[strlen(next_nsec_owner_str) - 1]
					= '\0';
			}
			status = ldns_str2rdf_b32_ext(&next_nsec_rdf,
									next_nsec_owner_str);
			if (!ldns_rr_set_rdf(ldns_rr_list_rr(nsec3_rrs, i),
							 next_nsec_rdf, 4)) {
				/* todo: error */
			}

			ldns_rdf_deep_free(next_nsec_owner_label);
			LDNS_FREE(next_nsec_owner_str);
		} else {
			next_nsec_owner_label =
				ldns_dname_label(ldns_rr_owner(ldns_rr_list_rr(nsec3_rrs,
													  i + 1)),
							  0);
			next_nsec_owner_str = ldns_rdf2str(next_nsec_owner_label);
			if (next_nsec_owner_str[strlen(next_nsec_owner_str) - 1]
			    == '.') {
				next_nsec_owner_str[strlen(next_nsec_owner_str) - 1]
					= '\0';
			}
			status = ldns_str2rdf_b32_ext(&next_nsec_rdf,
									next_nsec_owner_str);
			ldns_rdf_deep_free(next_nsec_owner_label);
			LDNS_FREE(next_nsec_owner_str);
			if (!ldns_rr_set_rdf(ldns_rr_list_rr(nsec3_rrs, i),
							 next_nsec_rdf, 4)) {
				/* todo: error */
			}
		}
	}
	return status;
}

int
qsort_rr_compare_nsec3(const void *a, const void *b)
{
	const ldns_rr *rr1 = * (const ldns_rr **) a;
	const ldns_rr *rr2 = * (const ldns_rr **) b;
	if (rr1 == NULL && rr2 == NULL) {
		return 0;
	}
	if (rr1 == NULL) {
		return -1;
	}
	if (rr2 == NULL) {
		return 1;
	}
	return ldns_rdf_compare(ldns_rr_owner(rr1), ldns_rr_owner(rr2));
}

void
ldns_rr_list_sort_nsec3(ldns_rr_list *unsorted)
{
	qsort(unsorted->_rrs,
	      ldns_rr_list_rr_count(unsorted),
	      sizeof(ldns_rr *),
	      qsort_rr_compare_nsec3);
}

int
ldns_dnssec_default_add_to_signatures( ATTR_UNUSED(ldns_rr *sig)
				     , ATTR_UNUSED(void *n)
				     )
{
	return LDNS_SIGNATURE_LEAVE_ADD_NEW;
}

int
ldns_dnssec_default_leave_signatures( ATTR_UNUSED(ldns_rr *sig)
				    , ATTR_UNUSED(void *n)
				    )
{
	return LDNS_SIGNATURE_LEAVE_NO_ADD;
}

int
ldns_dnssec_default_delete_signatures( ATTR_UNUSED(ldns_rr *sig)
				     , ATTR_UNUSED(void *n)
				     )
{
	return LDNS_SIGNATURE_REMOVE_NO_ADD;
}

int
ldns_dnssec_default_replace_signatures( ATTR_UNUSED(ldns_rr *sig)
				      , ATTR_UNUSED(void *n)
				      )
{
	return LDNS_SIGNATURE_REMOVE_ADD_NEW;
}

#ifdef HAVE_SSL
ldns_rdf *
ldns_convert_dsa_rrsig_asn12rdf(const ldns_buffer *sig,
						  const long sig_len)
{
	ldns_rdf *sigdata_rdf;
	DSA_SIG *dsasig;
	unsigned char *dsasig_data = (unsigned char*)ldns_buffer_begin(sig);
	size_t byte_offset;

	dsasig = d2i_DSA_SIG(NULL,
					 (const unsigned char **)&dsasig_data,
					 sig_len);
	if (!dsasig) {
                DSA_SIG_free(dsasig);
		return NULL;
	}

	dsasig_data = LDNS_XMALLOC(unsigned char, 41);
        if(!dsasig_data) {
                DSA_SIG_free(dsasig);
                return NULL;
        }
	dsasig_data[0] = 0;
	byte_offset = (size_t) (20 - BN_num_bytes(dsasig->r));
	if (byte_offset > 20) {
                DSA_SIG_free(dsasig);
                LDNS_FREE(dsasig_data);
		return NULL;
	}
	memset(&dsasig_data[1], 0, byte_offset);
	BN_bn2bin(dsasig->r, &dsasig_data[1 + byte_offset]);
	byte_offset = (size_t) (20 - BN_num_bytes(dsasig->s));
	if (byte_offset > 20) {
                DSA_SIG_free(dsasig);
                LDNS_FREE(dsasig_data);
		return NULL;
	}
	memset(&dsasig_data[21], 0, byte_offset);
	BN_bn2bin(dsasig->s, &dsasig_data[21 + byte_offset]);

	sigdata_rdf = ldns_rdf_new(LDNS_RDF_TYPE_B64, 41, dsasig_data);
        if(!sigdata_rdf) {
                LDNS_FREE(dsasig_data);
        }
	DSA_SIG_free(dsasig);

	return sigdata_rdf;
}

ldns_status
ldns_convert_dsa_rrsig_rdf2asn1(ldns_buffer *target_buffer,
						  const ldns_rdf *sig_rdf)
{
	/* the EVP api wants the DER encoding of the signature... */
	BIGNUM *R, *S;
	DSA_SIG *dsasig;
	unsigned char *raw_sig = NULL;
	int raw_sig_len;

        if(ldns_rdf_size(sig_rdf) < 1 + 2*SHA_DIGEST_LENGTH)
                return LDNS_STATUS_SYNTAX_RDATA_ERR;
	/* extract the R and S field from the sig buffer */
	R = BN_new();
	if(!R) return LDNS_STATUS_MEM_ERR;
	(void) BN_bin2bn((unsigned char *) ldns_rdf_data(sig_rdf) + 1,
	                 SHA_DIGEST_LENGTH, R);
	S = BN_new();
	if(!S) {
		BN_free(R);
		return LDNS_STATUS_MEM_ERR;
	}
	(void) BN_bin2bn((unsigned char *) ldns_rdf_data(sig_rdf) + 21,
	                 SHA_DIGEST_LENGTH, S);

	dsasig = DSA_SIG_new();
	if (!dsasig) {
		BN_free(R);
		BN_free(S);
		return LDNS_STATUS_MEM_ERR;
	}

	dsasig->r = R;
	dsasig->s = S;

	raw_sig_len = i2d_DSA_SIG(dsasig, &raw_sig);
	if (raw_sig_len < 0) {
		DSA_SIG_free(dsasig);
		free(raw_sig);
		return LDNS_STATUS_SSL_ERR;
	}
	if (ldns_buffer_reserve(target_buffer, (size_t) raw_sig_len)) {
		ldns_buffer_write(target_buffer, raw_sig, (size_t)raw_sig_len);
	}

	DSA_SIG_free(dsasig);
	free(raw_sig);

	return ldns_buffer_status(target_buffer);
}

#ifdef USE_ECDSA
#ifndef S_SPLINT_S
ldns_rdf *
ldns_convert_ecdsa_rrsig_asn12rdf(const ldns_buffer *sig, const long sig_len)
{
        ECDSA_SIG* ecdsa_sig;
	unsigned char *data = (unsigned char*)ldns_buffer_begin(sig);
        ldns_rdf* rdf;
	ecdsa_sig = d2i_ECDSA_SIG(NULL, (const unsigned char **)&data, sig_len);
        if(!ecdsa_sig) return NULL;

        /* "r | s". */
        data = LDNS_XMALLOC(unsigned char,
                BN_num_bytes(ecdsa_sig->r) + BN_num_bytes(ecdsa_sig->s));
        if(!data) {
                ECDSA_SIG_free(ecdsa_sig);
                return NULL;
        }
        BN_bn2bin(ecdsa_sig->r, data);
        BN_bn2bin(ecdsa_sig->s, data+BN_num_bytes(ecdsa_sig->r));
	rdf = ldns_rdf_new(LDNS_RDF_TYPE_B64, (size_t)(
		BN_num_bytes(ecdsa_sig->r) + BN_num_bytes(ecdsa_sig->s)), data);
        ECDSA_SIG_free(ecdsa_sig);
        return rdf;
}

ldns_status
ldns_convert_ecdsa_rrsig_rdf2asn1(ldns_buffer *target_buffer,
        const ldns_rdf *sig_rdf)
{
        ECDSA_SIG* sig;
	int raw_sig_len;
        long bnsize = (long)ldns_rdf_size(sig_rdf) / 2;
        /* if too short, or not even length, do not bother */
        if(bnsize < 16 || (size_t)bnsize*2 != ldns_rdf_size(sig_rdf))
                return LDNS_STATUS_ERR;

        /* use the raw data to parse two evenly long BIGNUMs, "r | s". */
        sig = ECDSA_SIG_new();
        if(!sig) return LDNS_STATUS_MEM_ERR;
        sig->r = BN_bin2bn((const unsigned char*)ldns_rdf_data(sig_rdf),
                bnsize, sig->r);
        sig->s = BN_bin2bn((const unsigned char*)ldns_rdf_data(sig_rdf)+bnsize,
                bnsize, sig->s);
        if(!sig->r || !sig->s) {
                ECDSA_SIG_free(sig);
                return LDNS_STATUS_MEM_ERR;
        }

	raw_sig_len = i2d_ECDSA_SIG(sig, NULL);
	if (ldns_buffer_reserve(target_buffer, (size_t) raw_sig_len)) {
                unsigned char* pp = (unsigned char*)
			ldns_buffer_current(target_buffer);
	        raw_sig_len = i2d_ECDSA_SIG(sig, &pp);
                ldns_buffer_skip(target_buffer, (ssize_t) raw_sig_len);
	}
        ECDSA_SIG_free(sig);

	return ldns_buffer_status(target_buffer);
}

#endif /* S_SPLINT_S */
#endif /* USE_ECDSA */
#endif /* HAVE_SSL */