rdata/in_1/a6_38.c

	a6_38.c revision 40f53fa8d9c6a4fc38c0014495e7a42b08f52481
/*
 * Copyright (C) 1999, 2000  Internet Software Consortium.
 *
 * Permission to use, copy, modify, and 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 INTERNET SOFTWARE CONSORTIUM
 * DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
 * INTERNET SOFTWARE CONSORTIUM 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: a6_38.c,v 1.36 2000/08/01 01:26:16 tale Exp $ */

/* draft-ietf-ipngwg-dns-lookups-03.txt */

#ifndef RDATA_IN_1_A6_28_C
#define RDATA_IN_1_A6_28_C

#include <isc/net.h>

#define RRTYPE_A6_ATTRIBUTES (0)

static inline isc_result_t
fromtext_in_a6(ARGS_FROMTEXT) {
    isc_token_t token;
    unsigned char addr[16];
    unsigned char prefixlen;
    unsigned char octets;
    unsigned char mask;
    dns_name_t name;
    isc_buffer_t buffer;

    REQUIRE(type == 38);
    REQUIRE(rdclass == 1);

    /*
     * Prefix length.
     */
    RETERR(gettoken(lexer, &token, isc_tokentype_number, ISC_FALSE));
    if (token.value.as_ulong > 128)
        return (ISC_R_RANGE);

    prefixlen = (unsigned char)token.value.as_ulong;
    RETERR(mem_tobuffer(target, &prefixlen, 1));

    /*
     * Suffix.
     */
    if (prefixlen != 128) {
        /*
         * Prefix 0..127.
         */
        octets = prefixlen/8;
        /*
         * Octets 0..15.
         */
        RETERR(gettoken(lexer, &token, isc_tokentype_string,
                ISC_FALSE));
        if (inet_pton(AF_INET6, token.value.as_pointer, addr) != 1)
            return (DNS_R_BADAAAA);
        mask = 0xff >> (prefixlen % 8);
        addr[octets] &= mask;
        RETERR(mem_tobuffer(target, &addr[octets], 16 - octets));
    }

    if (prefixlen == 0)
        return (ISC_R_SUCCESS);

    RETERR(gettoken(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;
    return (dns_name_fromtext(&name, &buffer, origin, downcase, target));
}

static inline isc_result_t
totext_in_a6(ARGS_TOTEXT) {
    isc_region_t tr;
    isc_region_t sr;
    unsigned char addr[16];
    unsigned char prefixlen;
    unsigned char octets;
    unsigned char mask;
    char buf[sizeof "128"];
    dns_name_t name;
    dns_name_t prefix;
    isc_boolean_t sub;

    REQUIRE(rdata->type == 38);
    REQUIRE(rdata->rdclass == 1);

    dns_rdata_toregion(rdata, &sr);
    prefixlen = sr.base[0];
    INSIST(prefixlen <= 128);
    isc_region_consume(&sr, 1);
    sprintf(buf, "%u", prefixlen);
    RETERR(str_totext(buf, target));
    RETERR(str_totext(" ", target));

    if (prefixlen != 128) {
        octets = prefixlen/8;
        memset(addr, 0, sizeof addr);
        memcpy(&addr[octets], sr.base, 16 - octets);
        mask = 0xff >> (prefixlen % 8);
        addr[octets] &= mask;
        isc_buffer_availableregion(target, &tr);
        if (inet_ntop(AF_INET6, addr,
                  (char *)tr.base, tr.length) == NULL)
            return (ISC_R_NOSPACE);

        isc_buffer_add(target, strlen((char *)tr.base));
        isc_region_consume(&sr, 16 - octets);
    }

    if (prefixlen == 0)
        return (ISC_R_SUCCESS);

    RETERR(str_totext(" ", target));
    dns_name_init(&name, NULL);
    dns_name_init(&prefix, NULL);
    dns_name_fromregion(&name, &sr);
    sub = name_prefix(&name, tctx->origin, &prefix);
    return (dns_name_totext(&prefix, sub, target));
}

static inline isc_result_t
fromwire_in_a6(ARGS_FROMWIRE) {
    isc_region_t sr;
    unsigned char prefixlen;
    unsigned char octets;
    unsigned char mask;
    dns_name_t name;

    REQUIRE(type == 38);
    REQUIRE(rdclass == 1);

    dns_decompress_setmethods(dctx, DNS_COMPRESS_NONE);

    isc_buffer_activeregion(source, &sr);
    /*
     * Prefix length.
     */
    if (sr.length < 1)
        return (ISC_R_UNEXPECTEDEND);
    prefixlen = sr.base[0];
    if (prefixlen > 128)
        return (ISC_R_RANGE);
    isc_region_consume(&sr, 1);
    RETERR(mem_tobuffer(target, &prefixlen, 1));
    isc_buffer_forward(source, 1);

    /*
     * Suffix.
     */
    if (prefixlen != 128) {
        octets = 16 - prefixlen / 8;
        if (sr.length < octets)
            return (ISC_R_UNEXPECTEDEND);
        mask = 0xff >> (prefixlen % 8);
        sr.base[0] &= mask; /* Ensure pad bits are zero. */
        RETERR(mem_tobuffer(target, sr.base, octets));
        isc_buffer_forward(source, octets);
    }

    if (prefixlen == 0)
        return (ISC_R_SUCCESS);

    dns_name_init(&name, NULL);
    return (dns_name_fromwire(&name, source, dctx, downcase, target));
}

static inline isc_result_t
towire_in_a6(ARGS_TOWIRE) {
    isc_region_t sr;
    dns_name_t name;
    unsigned char prefixlen;
    unsigned char octets;

    REQUIRE(rdata->type == 38);
    REQUIRE(rdata->rdclass == 1);

    dns_compress_setmethods(cctx, DNS_COMPRESS_NONE);
    dns_rdata_toregion(rdata, &sr);
    prefixlen = sr.base[0];
    INSIST(prefixlen <= 128);

    octets = 1 + 16 - prefixlen / 8;
    RETERR(mem_tobuffer(target, sr.base, octets));
    isc_region_consume(&sr, octets);

    if (prefixlen == 0)
        return (ISC_R_SUCCESS);

    dns_name_init(&name, NULL);
    dns_name_fromregion(&name, &sr);
    return (dns_name_towire(&name, cctx, target));
}

static inline int
compare_in_a6(ARGS_COMPARE) {
    int order;
    unsigned char prefixlen1, prefixlen2;
    unsigned char octets;
    dns_name_t name1;
    dns_name_t name2;
    isc_region_t region1;
    isc_region_t region2;

    REQUIRE(rdata1->type == rdata2->type);
    REQUIRE(rdata1->rdclass == rdata2->rdclass);
    REQUIRE(rdata1->type == 38);
    REQUIRE(rdata1->rdclass == 1);

    dns_rdata_toregion(rdata1, &region1);
    dns_rdata_toregion(rdata2, &region2);
    prefixlen1 = region1.base[0];
    prefixlen2 = region2.base[0];
    isc_region_consume(&region1, 1);
    isc_region_consume(&region2, 1);
    if (prefixlen1 < prefixlen2)
        return (-1);
    else if (prefixlen1 > prefixlen2)
        return (1);
    /*
     * Prefix lengths are equal.
     */
    octets = 16 - prefixlen1 / 8;

    if (octets > 0) {
        order = memcmp(region1.base, region2.base, octets);
        if (order < 0)
            return (-1);
        else if (order > 0)
            return (1);
        /*
         * Address suffixes are equal.
         */
        if (prefixlen1 == 0)
            return (order);
        isc_region_consume(&region1, octets);
        isc_region_consume(&region2, octets);
    }

    dns_name_init(&name1, NULL);
    dns_name_init(&name2, NULL);
    dns_name_fromregion(&name1, &region1);
    dns_name_fromregion(&name2, &region2);
    return (dns_name_rdatacompare(&name1, &name2));
}

static inline isc_result_t
fromstruct_in_a6(ARGS_FROMSTRUCT) {
    dns_rdata_in_a6_t *a6 = source;
    isc_region_t region;
    int octets;
    isc_uint8_t bits;
    isc_uint8_t first;
    isc_uint8_t mask;

    REQUIRE(type == 38);
    REQUIRE(rdclass == 1);
    REQUIRE(source != NULL);
    REQUIRE(a6->common.rdtype == type);
    REQUIRE(a6->common.rdclass == rdclass);

    if (a6->prefixlen > 128)
        return (ISC_R_RANGE);

    RETERR(uint8_tobuffer(a6->prefixlen, target));

    /* Suffix */
    if (a6->prefixlen != 128) {
        octets = 16 - a6->prefixlen / 8;
        bits = a6->prefixlen % 8;
        if (bits != 0) {
            mask = 0xffU >> bits;
            first = a6->in6_addr.s6_addr[16 - octets] & mask;
            RETERR(uint8_tobuffer(first, target));
            octets--;
        }
        if (octets > 0)
            RETERR(mem_tobuffer(target,
                        a6->in6_addr.s6_addr + 16 - octets,
                        octets));
    }

    if (a6->prefixlen == 0)
        return (ISC_R_SUCCESS);
    dns_name_toregion(&a6->prefix, &region);
    return (isc_buffer_copyregion(target, &region));
}

static inline isc_result_t
tostruct_in_a6(ARGS_TOSTRUCT) {
    dns_rdata_in_a6_t *a6 = target;
    unsigned char octets;
    dns_name_t name;
    isc_region_t r;

    REQUIRE(rdata->type == 38);
    REQUIRE(rdata->rdclass == 1);
    REQUIRE(target != NULL);

    a6->common.rdclass = rdata->rdclass;
    a6->common.rdtype = rdata->type;
    ISC_LINK_INIT(&a6->common, link);

    dns_rdata_toregion(rdata, &r);

    a6->prefixlen = uint8_fromregion(&r);
    isc_region_consume(&r, 1);
    memset(a6->in6_addr.s6_addr, 0, sizeof(a6->in6_addr.s6_addr));

    /*
     * Suffix.
     */
    if (a6->prefixlen != 128) {
        octets = 16 - a6->prefixlen / 8;
        INSIST(r.length >= octets);
        memcpy(a6->in6_addr.s6_addr + 16 - octets, r.base, octets);
        isc_region_consume(&r, octets);
    }

    /*
     * Prefix.
     */
    dns_name_init(&a6->prefix, NULL);
    if (a6->prefixlen != 0) {
        dns_name_init(&name, NULL);
        dns_name_fromregion(&name, &r);
        RETERR(name_duporclone(&name, mctx, &a6->prefix));
    }
    a6->mctx = mctx;
    return (ISC_R_SUCCESS);
}

static inline void
freestruct_in_a6(ARGS_FREESTRUCT) {
    dns_rdata_in_a6_t *a6 = source;

    REQUIRE(source != NULL);
    REQUIRE(a6->common.rdclass == 1);
    REQUIRE(a6->common.rdtype == 38);

    if (a6->mctx == NULL)
        return;

    if (dns_name_dynamic(&a6->prefix))
        dns_name_free(&a6->prefix, a6->mctx);
    a6->mctx = NULL;
}

static inline isc_result_t
additionaldata_in_a6(ARGS_ADDLDATA) {
    REQUIRE(rdata->type == 38);
    REQUIRE(rdata->rdclass == 1);

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

    return (ISC_R_SUCCESS);
}

static inline isc_result_t
digest_in_a6(ARGS_DIGEST) {
    isc_region_t r1, r2;
    unsigned char prefixlen, octets;
    isc_result_t result;
    dns_name_t name;

    REQUIRE(rdata->type == 38);
    REQUIRE(rdata->rdclass == 1);

    dns_rdata_toregion(rdata, &r1);
    r2 = r1;
    prefixlen = r1.base[0];
    octets = 1 + 16 - prefixlen / 8;

    r1.length = octets;
    result = (digest)(arg, &r1);
    if (result != ISC_R_SUCCESS)
        return (result);
    if (prefixlen == 0)
        return (ISC_R_SUCCESS);

    isc_region_consume(&r2, octets);
    dns_name_init(&name, NULL);
    dns_name_fromregion(&name, &r2);
    return (dns_name_digest(&name, digest, arg));
}

#endif  /* RDATA_IN_1_A6_38_C */