rdata/generic/nsec3_50.c

	nsec3_50.c revision 6098d364b690cb9dabf96e9664c4689c8559bd2e
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer/*
0c27b3fe77ac1d5094ba3521e8142d9e7973133fMark Andrews * Copyright (C) 2004  Internet Systems Consortium, Inc. ("ISC")
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer * Copyright (C) 2003  Internet Software Consortium.
0c27b3fe77ac1d5094ba3521e8142d9e7973133fMark Andrews *
0c27b3fe77ac1d5094ba3521e8142d9e7973133fMark Andrews * Permission to use, copy, modify, and distribute this software for any
0c27b3fe77ac1d5094ba3521e8142d9e7973133fMark Andrews * purpose with or without fee is hereby granted, provided that the above
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer * copyright notice and this permission notice appear in all copies.
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer *
70e5a7403f0e0a3bd292b8287c5fed5772c15270Automatic Updater * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer * PERFORMANCE OF THIS SOFTWARE.
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer */
31707708c585c53b61ca1edb2e224e6bb1b985a5Evan Hunt
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer/*
2f1c460beaa1e372255e7a1b8aad8996f011816dMark Andrews * Copyright (C) 2004  Nominet, Ltd.
2f1c460beaa1e372255e7a1b8aad8996f011816dMark Andrews *
2f1c460beaa1e372255e7a1b8aad8996f011816dMark Andrews * Permission to use, copy, modify, and distribute this software for any
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer * purpose with or without fee is hereby granted, provided that the above
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer * copyright notice and this permission notice appear in all copies.
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer *
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer * THE SOFTWARE IS PROVIDED "AS IS" AND NOMINET DISCLAIMS ALL WARRANTIES WITH
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer * PERFORMANCE OF THIS SOFTWARE.
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer */
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer/* RFC 5155 */
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer#ifndef RDATA_GENERIC_NSEC3_50_C
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer#define RDATA_GENERIC_NSEC3_50_C
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer#include <isc/iterated_hash.h>
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer#include <isc/base32.h>
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer#define RRTYPE_NSEC3_ATTRIBUTES DNS_RDATATYPEATTR_DNSSEC
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayerstatic inline isc_result_t
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayerfromtext_nsec3(ARGS_FROMTEXT) {
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    isc_token_t token;
31707708c585c53b61ca1edb2e224e6bb1b985a5Evan Hunt    unsigned char bm[8*1024]; /* 64k bits */
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    dns_rdatatype_t covered;
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    int octet;
c3c8823fed039b3a2b8e5ca8bc2f3301d1dd840eMark Andrews    int window;
f42c0dcca86f2009c089e27ba513cb6fc9ee88baEvan Hunt    unsigned int flags;
c3c8823fed039b3a2b8e5ca8bc2f3301d1dd840eMark Andrews    unsigned char hashalg;
c3c8823fed039b3a2b8e5ca8bc2f3301d1dd840eMark Andrews    isc_buffer_t b;
c3c8823fed039b3a2b8e5ca8bc2f3301d1dd840eMark Andrews
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    REQUIRE(type == 50);
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    UNUSED(type);
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    UNUSED(rdclass);
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    UNUSED(callbacks);
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    UNUSED(origin);
31707708c585c53b61ca1edb2e224e6bb1b985a5Evan Hunt    UNUSED(options);
31707708c585c53b61ca1edb2e224e6bb1b985a5Evan Hunt
c3c8823fed039b3a2b8e5ca8bc2f3301d1dd840eMark Andrews    /* Hash. */
f42c0dcca86f2009c089e27ba513cb6fc9ee88baEvan Hunt    RETERR(isc_lex_getmastertoken(lexer, &token, isc_tokentype_string,
c3c8823fed039b3a2b8e5ca8bc2f3301d1dd840eMark Andrews                      ISC_FALSE));
c3c8823fed039b3a2b8e5ca8bc2f3301d1dd840eMark Andrews    RETTOK(dns_hashalg_fromtext(&hashalg, &token.value.as_textregion));
c3c8823fed039b3a2b8e5ca8bc2f3301d1dd840eMark Andrews    RETERR(uint8_tobuffer(hashalg, target));
31707708c585c53b61ca1edb2e224e6bb1b985a5Evan Hunt
31707708c585c53b61ca1edb2e224e6bb1b985a5Evan Hunt    /* Flags. */
31707708c585c53b61ca1edb2e224e6bb1b985a5Evan Hunt    RETERR(isc_lex_getmastertoken(lexer, &token, isc_tokentype_number,
c3c8823fed039b3a2b8e5ca8bc2f3301d1dd840eMark Andrews                      ISC_FALSE));
f42c0dcca86f2009c089e27ba513cb6fc9ee88baEvan Hunt    flags = token.value.as_ulong;
c3c8823fed039b3a2b8e5ca8bc2f3301d1dd840eMark Andrews    if (flags > 255U)
c3c8823fed039b3a2b8e5ca8bc2f3301d1dd840eMark Andrews        RETTOK(ISC_R_RANGE);
c3c8823fed039b3a2b8e5ca8bc2f3301d1dd840eMark Andrews    RETERR(uint8_tobuffer(flags, target));
31707708c585c53b61ca1edb2e224e6bb1b985a5Evan Hunt
31707708c585c53b61ca1edb2e224e6bb1b985a5Evan Hunt    /* Iterations. */
31707708c585c53b61ca1edb2e224e6bb1b985a5Evan Hunt    RETERR(isc_lex_getmastertoken(lexer, &token, isc_tokentype_number,
31707708c585c53b61ca1edb2e224e6bb1b985a5Evan Hunt                      ISC_FALSE));
31707708c585c53b61ca1edb2e224e6bb1b985a5Evan Hunt    if (token.value.as_ulong > 0xffffU)
31707708c585c53b61ca1edb2e224e6bb1b985a5Evan Hunt        RETTOK(ISC_R_RANGE);
31707708c585c53b61ca1edb2e224e6bb1b985a5Evan Hunt    RETERR(uint16_tobuffer(token.value.as_ulong, target));
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    /* salt */
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    RETERR(isc_lex_getmastertoken(lexer, &token, isc_tokentype_string,
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer                      ISC_FALSE));
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    if (token.value.as_textregion.length > (255*2))
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer        RETTOK(DNS_R_TEXTTOOLONG);
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    if (strcmp(DNS_AS_STR(token), "-") == 0) {
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer        RETERR(uint8_tobuffer(0, target));
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    } else {
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer        RETERR(uint8_tobuffer(strlen(DNS_AS_STR(token)) / 2, target));
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer        RETERR(isc_hex_decodestring(DNS_AS_STR(token), target));
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    }
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    /*
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer     * Next hash a single base32hex word.
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer     */
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    RETERR(isc_lex_getmastertoken(lexer, &token, isc_tokentype_string,
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer                      ISC_FALSE));
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    isc_buffer_init(&b, bm, sizeof(bm));
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    RETTOK(isc_base32hex_decodestring(DNS_AS_STR(token), &b));
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    if (isc_buffer_usedlength(&b) > 0xffU)
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer        RETTOK(ISC_R_RANGE);
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    RETERR(uint8_tobuffer(isc_buffer_usedlength(&b), target));
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    RETERR(mem_tobuffer(target, &bm, isc_buffer_usedlength(&b)));
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    memset(bm, 0, sizeof(bm));
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    do {
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer        RETERR(isc_lex_getmastertoken(lexer, &token,
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer                          isc_tokentype_string, ISC_TRUE));
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer        if (token.type != isc_tokentype_string)
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer            break;
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer        RETTOK(dns_rdatatype_fromtext(&covered,
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer                          &token.value.as_textregion));
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer        bm[covered/8] |= (0x80>>(covered%8));
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    } while (1);
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    isc_lex_ungettoken(lexer, &token);
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    for (window = 0; window < 256 ; window++) {
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer        /*
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer         * Find if we have a type in this window.
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer         */
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer        for (octet = 31; octet >= 0; octet--)
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer            if (bm[window * 32 + octet] != 0)
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer                break;
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer        if (octet < 0)
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer            continue;
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer        RETERR(uint8_tobuffer(window, target));
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer        RETERR(uint8_tobuffer(octet + 1, target));
2f1c460beaa1e372255e7a1b8aad8996f011816dMark Andrews        RETERR(mem_tobuffer(target, &bm[window * 32], octet + 1));
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    }
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    return (ISC_R_SUCCESS);
2f1c460beaa1e372255e7a1b8aad8996f011816dMark Andrews}
2f1c460beaa1e372255e7a1b8aad8996f011816dMark Andrews
2f1c460beaa1e372255e7a1b8aad8996f011816dMark Andrewsstatic inline isc_result_t
2f1c460beaa1e372255e7a1b8aad8996f011816dMark Andrewstotext_nsec3(ARGS_TOTEXT) {
2f1c460beaa1e372255e7a1b8aad8996f011816dMark Andrews    isc_region_t sr;
2f1c460beaa1e372255e7a1b8aad8996f011816dMark Andrews    unsigned int i, j, k;
2f1c460beaa1e372255e7a1b8aad8996f011816dMark Andrews    unsigned int window, len;
2f1c460beaa1e372255e7a1b8aad8996f011816dMark Andrews    unsigned char hash;
2f1c460beaa1e372255e7a1b8aad8996f011816dMark Andrews    unsigned char flags;
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    char buf[sizeof("65535 ")];
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    isc_uint32_t iterations;
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    REQUIRE(rdata->type == 50);
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    REQUIRE(rdata->length != 0);
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer
9ecea05b89aca9e8411ae5bb1ea7f185e06615a3Danny Mayer    UNUSED(tctx);

    dns_rdata_toregion(rdata, &sr);

    hash = uint8_fromregion(&sr);
    isc_region_consume(&sr, 1);

    flags = uint8_fromregion(&sr);
    isc_region_consume(&sr, 1);

    iterations = uint16_fromregion(&sr);
    isc_region_consume(&sr, 2);

    sprintf(buf, "%u ", hash);
    RETERR(str_totext(buf, target));

    sprintf(buf, "%u ", flags);
    RETERR(str_totext(buf, target));

    sprintf(buf, "%u ", iterations);
    RETERR(str_totext(buf, target));

    j = uint8_fromregion(&sr);
    isc_region_consume(&sr, 1);
    INSIST(j <= sr.length);

    if (j != 0) {
        i = sr.length;
        sr.length = j;
        RETERR(isc_hex_totext(&sr, 1, "", target));
        sr.length = i - j;
        RETERR(str_totext(" ", target));
    } else
        RETERR(str_totext("- ", target));

    j = uint8_fromregion(&sr);
    isc_region_consume(&sr, 1);
    INSIST(j <= sr.length);

    i = sr.length;
    sr.length = j;
    RETERR(isc_base32hex_totext(&sr, 1, "", target));
    sr.length = i - j;

    for (i = 0; i < sr.length; i += len) {
        INSIST(i + 2 <= sr.length);
        window = sr.base[i];
        len = sr.base[i + 1];
        INSIST(len > 0 && len <= 32);
        i += 2;
        INSIST(i + len <= sr.length);
        for (j = 0; j < len; j++) {
            dns_rdatatype_t t;
            if (sr.base[i + j] == 0)
                continue;
            for (k = 0; k < 8; k++) {
                if ((sr.base[i + j] & (0x80 >> k)) == 0)
                    continue;
                t = window * 256 + j * 8 + k;
                RETERR(str_totext(" ", target));
                if (dns_rdatatype_isknown(t)) {
                    RETERR(dns_rdatatype_totext(t, target));
                } else {
                    char buf[sizeof("TYPE65535")];
                    sprintf(buf, "TYPE%u", t);
                    RETERR(str_totext(buf, target));
                }
            }
        }
    }
    return (ISC_R_SUCCESS);
}

static inline isc_result_t
fromwire_nsec3(ARGS_FROMWIRE) {
    isc_region_t sr, rr;
    unsigned int window, lastwindow = 0;
    unsigned int len;
    unsigned int saltlen, hashlen;
    isc_boolean_t first = ISC_TRUE;
    unsigned int i;

    REQUIRE(type == 50);

    UNUSED(type);
    UNUSED(rdclass);
    UNUSED(options);
    UNUSED(dctx);

    isc_buffer_activeregion(source, &sr);
    rr = sr;

    /* hash(1), flags(1), interation(2), saltlen(1) */
    if (sr.length < 5U)
        RETERR(DNS_R_FORMERR);
    saltlen = sr.base[4];
    isc_region_consume(&sr, 5);

    if (sr.length < saltlen)
        RETERR(DNS_R_FORMERR);
    isc_region_consume(&sr, saltlen);

    if (sr.length < 1U)
        RETERR(DNS_R_FORMERR);
    hashlen = sr.base[0];
    isc_region_consume(&sr, 1);

    if (sr.length < hashlen)
        RETERR(DNS_R_FORMERR);
    isc_region_consume(&sr, hashlen);

    for (i = 0; i < sr.length; i += len) {
        /*
         * Check for overflow.
         */
        if (i + 2 > sr.length)
            RETERR(DNS_R_FORMERR);
        window = sr.base[i];
        len = sr.base[i + 1];
        i += 2;
        /*
         * Check that bitmap windows are in the correct order.
         */
        if (!first && window <= lastwindow)
            RETERR(DNS_R_FORMERR);
        /*
         * Check for legal lengths.
         */
        if (len < 1 || len > 32)
            RETERR(DNS_R_FORMERR);
        /*
         * Check for overflow.
         */
        if (i + len > sr.length)
            RETERR(DNS_R_FORMERR);
        /*
         * The last octet of the bitmap must be non zero.
         */
        if (sr.base[i + len - 1] == 0)
            RETERR(DNS_R_FORMERR);
        lastwindow = window;
        first = ISC_FALSE;
    }
    if (i != sr.length)
        return (DNS_R_EXTRADATA);
    RETERR(mem_tobuffer(target, rr.base, rr.length));
    isc_buffer_forward(source, rr.length);
    return (ISC_R_SUCCESS);
}

static inline isc_result_t
towire_nsec3(ARGS_TOWIRE) {
    isc_region_t sr;

    REQUIRE(rdata->type == 50);
    REQUIRE(rdata->length != 0);

    UNUSED(cctx);

    dns_rdata_toregion(rdata, &sr);
    return (mem_tobuffer(target, sr.base, sr.length));
}

static inline int
compare_nsec3(ARGS_COMPARE) {
    isc_region_t r1;
    isc_region_t r2;

    REQUIRE(rdata1->type == rdata2->type);
    REQUIRE(rdata1->rdclass == rdata2->rdclass);
    REQUIRE(rdata1->type == 50);
    REQUIRE(rdata1->length != 0);
    REQUIRE(rdata2->length != 0);

    dns_rdata_toregion(rdata1, &r1);
    dns_rdata_toregion(rdata2, &r2);
    return (isc_region_compare(&r1, &r2));
}

static inline isc_result_t
fromstruct_nsec3(ARGS_FROMSTRUCT) {
    dns_rdata_nsec3_t *nsec3 = source;
    unsigned int i, len, window, lastwindow = 0;
    isc_boolean_t first = ISC_TRUE;

    REQUIRE(type == 50);
    REQUIRE(source != NULL);
    REQUIRE(nsec3->common.rdtype == type);
    REQUIRE(nsec3->common.rdclass == rdclass);
    REQUIRE(nsec3->typebits != NULL || nsec3->len == 0);
    REQUIRE(nsec3->hash == dns_hash_sha1);

    UNUSED(type);
    UNUSED(rdclass);

    RETERR(uint8_tobuffer(nsec3->hash, target));
    RETERR(uint8_tobuffer(nsec3->flags, target));
    RETERR(uint16_tobuffer(nsec3->iterations, target));
    RETERR(uint8_tobuffer(nsec3->salt_length, target));
    RETERR(mem_tobuffer(target, nsec3->salt, nsec3->salt_length));
    RETERR(uint8_tobuffer(nsec3->next_length, target));
    RETERR(mem_tobuffer(target, nsec3->next, nsec3->next_length));

    /*
     * Perform sanity check.
     */
    for (i = 0; i < nsec3->len ; i += len) {
        INSIST(i + 2 <= nsec3->len);
        window = nsec3->typebits[i];
        len = nsec3->typebits[i+1];
        i += 2;
        INSIST(first || window > lastwindow);
        INSIST(len > 0 && len <= 32);
        INSIST(i + len <= nsec3->len);
        INSIST(nsec3->typebits[i + len - 1] != 0);
        lastwindow = window;
        first = ISC_FALSE;
    }
    return (mem_tobuffer(target, nsec3->typebits, nsec3->len));
}

static inline isc_result_t
tostruct_nsec3(ARGS_TOSTRUCT) {
    isc_region_t region;
    dns_rdata_nsec3_t *nsec3 = target;

    REQUIRE(rdata->type == 50);
    REQUIRE(target != NULL);
    REQUIRE(rdata->length != 0);

    nsec3->common.rdclass = rdata->rdclass;
    nsec3->common.rdtype = rdata->type;
    ISC_LINK_INIT(&nsec3->common, link);

    region.base = rdata->data;
    region.length = rdata->length;
    nsec3->hash = uint8_consume_fromregion(&region);
    nsec3->flags = uint8_consume_fromregion(&region);
    nsec3->iterations = uint16_consume_fromregion(&region);

    nsec3->salt_length = uint8_consume_fromregion(&region);
    nsec3->salt = mem_maybedup(mctx, region.base, nsec3->salt_length);
    if (nsec3->salt == NULL)
        return (ISC_R_NOMEMORY);
    isc_region_consume(&region, nsec3->salt_length);

    nsec3->next_length = uint8_consume_fromregion(&region);
    nsec3->next = mem_maybedup(mctx, region.base, nsec3->next_length);
    if (nsec3->next == NULL)
        goto cleanup;
    isc_region_consume(&region, nsec3->next_length);

    nsec3->len = region.length;
    nsec3->typebits = mem_maybedup(mctx, region.base, region.length);
    if (nsec3->typebits == NULL)
        goto cleanup;

    nsec3->mctx = mctx;
    return (ISC_R_SUCCESS);

  cleanup:
    if (nsec3->next != NULL)
        isc_mem_free(mctx, nsec3->next);
    isc_mem_free(mctx, nsec3->salt);
    return (ISC_R_NOMEMORY);
}

static inline void
freestruct_nsec3(ARGS_FREESTRUCT) {
    dns_rdata_nsec3_t *nsec3 = source;

    REQUIRE(source != NULL);
    REQUIRE(nsec3->common.rdtype == 50);

    if (nsec3->mctx == NULL)
        return;

    if (nsec3->salt != NULL)
        isc_mem_free(nsec3->mctx, nsec3->salt);
    if (nsec3->next != NULL)
        isc_mem_free(nsec3->mctx, nsec3->next);
    if (nsec3->typebits != NULL)
        isc_mem_free(nsec3->mctx, nsec3->typebits);
    nsec3->mctx = NULL;
}

static inline isc_result_t
additionaldata_nsec3(ARGS_ADDLDATA) {
    REQUIRE(rdata->type == 50);

    UNUSED(rdata);
    UNUSED(add);
    UNUSED(arg);

    return (ISC_R_SUCCESS);
}

static inline isc_result_t
digest_nsec3(ARGS_DIGEST) {
    isc_region_t r;

    REQUIRE(rdata->type == 50);

    dns_rdata_toregion(rdata, &r);
    return ((digest)(arg, &r));
}

static inline isc_boolean_t
checkowner_nsec3(ARGS_CHECKOWNER) {

       REQUIRE(type == 50);

       UNUSED(name);
       UNUSED(type);
       UNUSED(rdclass);
       UNUSED(wildcard);

       return (ISC_TRUE);
}

static inline isc_boolean_t
checknames_nsec3(ARGS_CHECKNAMES) {

    REQUIRE(rdata->type == 50);

    UNUSED(rdata);
    UNUSED(owner);
    UNUSED(bad);

    return (ISC_TRUE);
}

#endif  /* RDATA_GENERIC_NSEC3_50_C */