dnssec.c

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/*
 * 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(const 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(const ldns_rdf *qname,
                                   ATTR_UNUSED(ldns_rr_type qtype),
                                   const 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,
                                                                        const 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(const 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(const ldns_buffer *key)
{
        return ldns_key_buf2dsa_raw((const unsigned char*)ldns_buffer_begin(key),
                                                   ldns_buffer_position(key));
}
 
DSA *
ldns_key_buf2dsa_raw(const 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;
        }
#if OPENSSL_VERSION_NUMBER < 0x10100000 || defined(HAVE_LIBRESSL)
#ifndef S_SPLINT_S
        dsa->p = P;
        dsa->q = Q;
        dsa->g = G;
        dsa->pub_key = Y;
#endif /* splint */
#else /* OPENSSL_VERSION_NUMBER */
        if (!DSA_set0_pqg(dsa, P, Q, G)) {
                /* QPG not yet attached, need to free */
                BN_free(Q);
                BN_free(P);
                BN_free(G);
 
                DSA_free(dsa);
                BN_free(Y);
                return NULL;
        }
        if (!DSA_set0_key(dsa, Y, NULL)) {
                /* QPG attached, cleaned up by DSA_fre() */
                DSA_free(dsa);
                BN_free(Y);
                return NULL;
        }
#endif /* OPENSSL_VERSION_NUMBER */
        return dsa;
}
 
RSA *
ldns_key_buf2rsa(const ldns_buffer *key)
{
        return ldns_key_buf2rsa_raw((const unsigned char*)ldns_buffer_begin(key),
                                                   ldns_buffer_position(key));
}
 
RSA *
ldns_key_buf2rsa_raw(const 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;
        }
#if OPENSSL_VERSION_NUMBER < 0x10100000 || defined(HAVE_LIBRESSL)
#ifndef S_SPLINT_S
        rsa->n = modulus;
        rsa->e = exponent;
#endif /* splint */
#else /* OPENSSL_VERSION_NUMBER */
        if (!RSA_set0_key(rsa, modulus, exponent, NULL)) {
                BN_free(exponent);
                BN_free(modulus);
                RSA_free(rsa);
                return NULL;
        }
#endif /* OPENSSL_VERSION_NUMBER */
 
        return rsa;
}
 
int
ldns_digest_evp(const 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 */
        int      windows[256];          /* Max subtype per window */
        uint8_t  windowpresent[256];    /* bool if window appears in bitmap */
        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;
        }
        memset(windows, 0, sizeof(int)*256);
        memset(windowpresent, 0, 256);
 
        /* 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;
                windowpresent[window] = 1;
                if (windows[window] < (int)subtype) {
                        windows[window] = (int)subtype;
                }
        }
 
        /* How much space do we need in the rdf for those windows?
         */
        sz = 0;
        for (i = 0; i < 256; i++) {
                if (windowpresent[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 (windowpresent[i]) {
                                *dptr++ = (uint8_t)i;
                                *dptr++ = (uint8_t)(windows[i] / 8 + 1);
 
                                /* Now let windows[i] index the bitmap
                                 * within data
                                 */
                                windows[i] = (int)(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(const ldns_dnssec_rrsets *rrsets,
                                 ldns_rr_type type)
{
        const 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(const ldns_dnssec_name *from,
                        const 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(const ldns_dnssec_name *from,
                                        const ldns_dnssec_name *to,
                                        const ldns_rdf *zone_name,
                                        uint8_t algorithm,
                                        uint8_t flags,
                                        uint16_t iterations,
                                        uint8_t salt_length,
                                        const 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(const ldns_rdf *name,
                                 uint8_t algorithm,
                                 uint16_t iterations,
                                 uint8_t salt_length,
                                 const 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,
                                         const 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(const ldns_rdf *origin, const 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(const ldns_rdf *cur_owner,
                  const ldns_rdf *cur_zone,
                  const ldns_rr_list *rrs,
                  uint8_t algorithm,
                  uint8_t flags,
                  uint16_t iterations,
                  uint8_t salt_length,
                  const 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, const 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(const ldns_pkt *p, ldns_rr_type t, const ldns_rdf *o, 
                const ldns_rr_list *k, const 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 = (ldns_rr_list *)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(const ldns_pkt *p, ldns_rr_type t, const ldns_rdf *o, 
                const ldns_rr_list *k, const 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)
{
#ifdef USE_DSA
        ldns_rdf *sigdata_rdf;
        DSA_SIG *dsasig;
        const BIGNUM *R, *S;
        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;
# ifdef HAVE_DSA_SIG_GET0
        DSA_SIG_get0(dsasig, &R, &S);
# else
        R = dsasig->r;
        S = dsasig->s;
# endif
        byte_offset = (size_t) (20 - BN_num_bytes(R));
        if (byte_offset > 20) {
                DSA_SIG_free(dsasig);
                LDNS_FREE(dsasig_data);
                return NULL;
        }
        memset(&dsasig_data[1], 0, byte_offset);
        BN_bn2bin(R, &dsasig_data[1 + byte_offset]);
        byte_offset = (size_t) (20 - BN_num_bytes(S));
        if (byte_offset > 20) {
                DSA_SIG_free(dsasig);
                LDNS_FREE(dsasig_data);
                return NULL;
        }
        memset(&dsasig_data[21], 0, byte_offset);
        BN_bn2bin(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;
#else
        (void)sig; (void)sig_len;
        return NULL;
#endif
}
 
ldns_status
ldns_convert_dsa_rrsig_rdf2asn1(ldns_buffer *target_buffer,
                                                  const ldns_rdf *sig_rdf)
{
#ifdef USE_DSA
        /* 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;
        }
# ifdef HAVE_DSA_SIG_SET0
       if (! DSA_SIG_set0(dsasig, R, S))
               return LDNS_STATUS_SSL_ERR;
# else
        dsasig->r = R;
        dsasig->s = S;
# endif
 
        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);
#else
        (void)target_buffer; (void)sig_rdf;
        return LDNS_STATUS_CRYPTO_ALGO_NOT_IMPL;
#endif
}
 
#ifdef USE_ECDSA
#ifndef S_SPLINT_S
ldns_rdf *
ldns_convert_ecdsa_rrsig_asn1len2rdf(const ldns_buffer *sig,
        const long sig_len, int num_bytes)
{
        ECDSA_SIG* ecdsa_sig;
        const BIGNUM *r, *s;
        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;
 
#ifdef HAVE_ECDSA_SIG_GET0
        ECDSA_SIG_get0(ecdsa_sig, &r, &s);
#else
        r = ecdsa_sig->r;
        s = ecdsa_sig->s;
#endif
        /* "r | s". */
        if(BN_num_bytes(r) > num_bytes ||
                BN_num_bytes(s) > num_bytes) {
                ECDSA_SIG_free(ecdsa_sig);
                return NULL; /* numbers too big for passed curve size */
        }
        data = LDNS_XMALLOC(unsigned char, num_bytes*2);
        if(!data) {
                ECDSA_SIG_free(ecdsa_sig);
                return NULL;
        }
        /* write the bignums (in big-endian) a little offset if the BN code
         * wants to write a shorter number of bytes, with zeroes prefixed */
        memset(data, 0, num_bytes*2);
        BN_bn2bin(r, data+num_bytes-BN_num_bytes(r));
        BN_bn2bin(s, data+num_bytes*2-BN_num_bytes(s));
        rdf = ldns_rdf_new(LDNS_RDF_TYPE_B64, (size_t)(num_bytes*2), data);
        ECDSA_SIG_free(ecdsa_sig);
        return rdf;
}
 
ldns_status
ldns_convert_ecdsa_rrsig_rdf2asn1(ldns_buffer *target_buffer,
        const ldns_rdf *sig_rdf)
{
        /* convert from two BIGNUMs in the rdata buffer, to ASN notation.
         * ASN preable:  30440220 <R 32bytefor256> 0220 <S 32bytefor256>
         * the '20' is the length of that field (=bnsize).
         * the '44' is the total remaining length.
         * if negative, start with leading zero.
         * if starts with 00s, remove them from the number.
         */
        uint8_t pre[] = {0x30, 0x44, 0x02, 0x20};
        int pre_len = 4;
        uint8_t mid[] = {0x02, 0x20};
        int mid_len = 2;
        int raw_sig_len, r_high, s_high, r_rem=0, s_rem=0;
        long bnsize = (long)ldns_rdf_size(sig_rdf) / 2;
        uint8_t* d = ldns_rdf_data(sig_rdf);
        /* 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;
        /* strip leading zeroes from r (but not last one) */
        while(r_rem < bnsize-1 && d[r_rem] == 0)
                r_rem++;
        /* strip leading zeroes from s (but not last one) */
        while(s_rem < bnsize-1 && d[bnsize+s_rem] == 0)
                s_rem++;
 
        r_high = ((d[0+r_rem]&0x80)?1:0);
        s_high = ((d[bnsize+s_rem]&0x80)?1:0);
        raw_sig_len = pre_len + r_high + bnsize - r_rem + mid_len +
                s_high + bnsize - s_rem;
        if(ldns_buffer_reserve(target_buffer, (size_t) raw_sig_len)) {
                ldns_buffer_write_u8(target_buffer, pre[0]);
                ldns_buffer_write_u8(target_buffer, raw_sig_len-2);
                ldns_buffer_write_u8(target_buffer, pre[2]);
                ldns_buffer_write_u8(target_buffer, bnsize + r_high - r_rem);
                if(r_high)
                        ldns_buffer_write_u8(target_buffer, 0);
                ldns_buffer_write(target_buffer, d+r_rem, bnsize-r_rem);
                ldns_buffer_write(target_buffer, mid, mid_len-1);
                ldns_buffer_write_u8(target_buffer, bnsize + s_high - s_rem);
                if(s_high)
                        ldns_buffer_write_u8(target_buffer, 0);
                ldns_buffer_write(target_buffer, d+bnsize+s_rem, bnsize-s_rem);
        }
        return ldns_buffer_status(target_buffer);
}
 
#endif /* S_SPLINT_S */
#endif /* USE_ECDSA */
 
#if defined(USE_ED25519) || defined(USE_ED448)
/* debug printout routine */
static void print_hex(const char* str, uint8_t* d, int len)
{
        const char hex[] = "0123456789abcdef";
        int i;
        printf("%s [len=%d]: ", str, len);
        for(i=0; i<len; i++) {
                int x = (d[i]&0xf0)>>4;
                int y = (d[i]&0x0f);
                printf("%c%c", hex[x], hex[y]);
        }
        printf("\n");
}
#endif
 
#ifdef USE_ED25519
ldns_rdf *
ldns_convert_ed25519_rrsig_asn12rdf(const ldns_buffer *sig, long sig_len)
{
        unsigned char *data = (unsigned char*)ldns_buffer_begin(sig);
        ldns_rdf* rdf = NULL;
 
        /* TODO when Openssl supports signing and you can test this */
        print_hex("sig in ASN", data, sig_len);
 
        return rdf;
}
 
ldns_status
ldns_convert_ed25519_rrsig_rdf2asn1(ldns_buffer *target_buffer,
        const ldns_rdf *sig_rdf)
{
        /* TODO when Openssl supports signing and you can test this. */
        /* convert sig_buf into ASN1 into the target_buffer */
        print_hex("sig raw", ldns_rdf_data(sig_rdf), ldns_rdf_size(sig_rdf));
        return ldns_buffer_status(target_buffer);
}
#endif /* USE_ED25519 */
 
#ifdef USE_ED448
ldns_rdf *
ldns_convert_ed448_rrsig_asn12rdf(const ldns_buffer *sig, long sig_len)
{
        unsigned char *data = (unsigned char*)ldns_buffer_begin(sig);
        ldns_rdf* rdf = NULL;
 
        /* TODO when Openssl supports signing and you can test this */
        print_hex("sig in ASN", data, sig_len);
 
        return rdf;
}
 
ldns_status
ldns_convert_ed448_rrsig_rdf2asn1(ldns_buffer *target_buffer,
        const ldns_rdf *sig_rdf)
{
        /* TODO when Openssl supports signing and you can test this. */
        /* convert sig_buf into ASN1 into the target_buffer */
        print_hex("sig raw", ldns_rdf_data(sig_rdf), ldns_rdf_size(sig_rdf));
        return ldns_buffer_status(target_buffer);
}
#endif /* USE_ED448 */
 
#endif /* HAVE_SSL */