rdata/generic/nsec_47.c

/*
 * Copyright (C) 2004, 2007, 2008, 2011, 2012  Internet Systems Consortium, Inc. ("ISC")
 * Copyright (C) 2003  Internet Software Consortium.
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
 * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
 * PERFORMANCE OF THIS SOFTWARE.
 */

/* $Id$ */

/* reviewed: Wed Mar 15 18:21:15 PST 2000 by brister */

/* RFC 3845 */

#ifndef RDATA_GENERIC_NSEC_47_C
#define RDATA_GENERIC_NSEC_47_C

/*
 * The attributes do not include DNS_RDATATYPEATTR_SINGLETON
 * because we must be able to handle a parent/child NSEC pair.
 */
#define RRTYPE_NSEC_ATTRIBUTES (DNS_RDATATYPEATTR_DNSSEC)

static inline isc_result_t
fromtext_nsec(ARGS_FROMTEXT) {
    isc_token_t token;
    dns_name_t name;
    isc_buffer_t buffer;
    unsigned char bm[8*1024]; /* 64k bits */
    dns_rdatatype_t covered;
    int octet;
    int window;

    REQUIRE(type == 47);

    UNUSED(type);
    UNUSED(rdclass);
    UNUSED(callbacks);

    /*
     * Next domain.
     */
    RETERR(isc_lex_getmastertoken(lexer, &token, isc_tokentype_string,
                      ISC_FALSE));
    dns_name_init(&name, NULL);
    buffer_fromregion(&buffer, &token.value.as_region);
    origin = (origin != NULL) ? origin : dns_rootname;
    RETTOK(dns_name_fromtext(&name, &buffer, origin, options, target));

    memset(bm, 0, sizeof(bm));
    do {
        RETERR(isc_lex_getmastertoken(lexer, &token,
                          isc_tokentype_string, ISC_TRUE));
        if (token.type != isc_tokentype_string)
            break;
        RETTOK(dns_rdatatype_fromtext(&covered,
                          &token.value.as_textregion));
        bm[covered/8] |= (0x80>>(covered%8));
    } while (1);
    isc_lex_ungettoken(lexer, &token);
    for (window = 0; window < 256 ; window++) {
        /*
         * Find if we have a type in this window.
         */
        for (octet = 31; octet >= 0; octet--)
            if (bm[window * 32 + octet] != 0)
                break;
        if (octet < 0)
            continue;
        RETERR(uint8_tobuffer(window, target));
        RETERR(uint8_tobuffer(octet + 1, target));
        RETERR(mem_tobuffer(target, &bm[window * 32], octet + 1));
    }
    return (ISC_R_SUCCESS);
}

static inline isc_result_t
totext_nsec(ARGS_TOTEXT) {
    isc_region_t sr;
    unsigned int i, j, k;
    dns_name_t name;
    unsigned int window, len;

    REQUIRE(rdata->type == 47);
    REQUIRE(rdata->length != 0);

    UNUSED(tctx);

    dns_name_init(&name, NULL);
    dns_rdata_toregion(rdata, &sr);
    dns_name_fromregion(&name, &sr);
    isc_region_consume(&sr, name_length(&name));
    RETERR(dns_name_totext(&name, ISC_FALSE, target));


    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_nsec(ARGS_FROMWIRE) {
    isc_region_t sr;
    dns_name_t name;
    unsigned int window, lastwindow = 0;
    unsigned int len;
    isc_boolean_t first = ISC_TRUE;
    unsigned int i;

    REQUIRE(type == 47);

    UNUSED(type);
    UNUSED(rdclass);

    dns_decompress_setmethods(dctx, DNS_COMPRESS_NONE);

    dns_name_init(&name, NULL);
    RETERR(dns_name_fromwire(&name, source, dctx, options, target));

    isc_buffer_activeregion(source, &sr);
    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);
    if (first)
        RETERR(DNS_R_FORMERR);
    RETERR(mem_tobuffer(target, sr.base, sr.length));
    isc_buffer_forward(source, sr.length);
    return (ISC_R_SUCCESS);
}

static inline isc_result_t
towire_nsec(ARGS_TOWIRE) {
    isc_region_t sr;
    dns_name_t name;
    dns_offsets_t offsets;

    REQUIRE(rdata->type == 47);
    REQUIRE(rdata->length != 0);

    dns_compress_setmethods(cctx, DNS_COMPRESS_NONE);
    dns_name_init(&name, offsets);
    dns_rdata_toregion(rdata, &sr);
    dns_name_fromregion(&name, &sr);
    isc_region_consume(&sr, name_length(&name));
    RETERR(dns_name_towire(&name, cctx, target));

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

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

    REQUIRE(rdata1->type == rdata2->type);
    REQUIRE(rdata1->rdclass == rdata2->rdclass);
    REQUIRE(rdata1->type == 47);
    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_nsec(ARGS_FROMSTRUCT) {
    dns_rdata_nsec_t *nsec = source;
    isc_region_t region;
    unsigned int i, len, window, lastwindow = 0;
    isc_boolean_t first = ISC_TRUE;

    REQUIRE(type == 47);
    REQUIRE(source != NULL);
    REQUIRE(nsec->common.rdtype == type);
    REQUIRE(nsec->common.rdclass == rdclass);
    REQUIRE(nsec->typebits != NULL || nsec->len == 0);

    UNUSED(type);
    UNUSED(rdclass);

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

static inline isc_result_t
tostruct_nsec(ARGS_TOSTRUCT) {
    isc_region_t region;
    dns_rdata_nsec_t *nsec = target;
    dns_name_t name;

    REQUIRE(rdata->type == 47);
    REQUIRE(target != NULL);
    REQUIRE(rdata->length != 0);

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

    dns_name_init(&name, NULL);
    dns_rdata_toregion(rdata, &region);
    dns_name_fromregion(&name, &region);
    isc_region_consume(&region, name_length(&name));
    dns_name_init(&nsec->next, NULL);
    RETERR(name_duporclone(&name, mctx, &nsec->next));

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

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

 cleanup:
    if (mctx != NULL)
        dns_name_free(&nsec->next, mctx);
    return (ISC_R_NOMEMORY);
}

static inline void
freestruct_nsec(ARGS_FREESTRUCT) {
    dns_rdata_nsec_t *nsec = source;

    REQUIRE(source != NULL);
    REQUIRE(nsec->common.rdtype == 47);

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

    dns_name_free(&nsec->next, nsec->mctx);
    if (nsec->typebits != NULL)
        isc_mem_free(nsec->mctx, nsec->typebits);
    nsec->mctx = NULL;
}

static inline isc_result_t
additionaldata_nsec(ARGS_ADDLDATA) {
    REQUIRE(rdata->type == 47);

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

    return (ISC_R_SUCCESS);
}

static inline isc_result_t
digest_nsec(ARGS_DIGEST) {
    isc_region_t r;

    REQUIRE(rdata->type == 47);

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

static inline isc_boolean_t
checkowner_nsec(ARGS_CHECKOWNER) {

       REQUIRE(type == 47);

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

       return (ISC_TRUE);
}

static inline isc_boolean_t
checknames_nsec(ARGS_CHECKNAMES) {

    REQUIRE(rdata->type == 47);

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

    return (ISC_TRUE);
}

#endif  /* RDATA_GENERIC_NSEC_47_C */