a6_38.c

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/*
 * Copyright (C) 2004, 2007, 2009, 2014  Internet Systems Consortium, Inc. ("ISC")
 * Copyright (C) 1999-2003  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: a6_38.c,v 1.56 2009/12/04 22:06:37 tbox Exp $ */

/* RFC2874 */

#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;
        isc_boolean_t ok;

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

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

        /*
         * Prefix length.
         */
        RETERR(isc_lex_getmastertoken(lexer, &token, isc_tokentype_number,
                                      ISC_FALSE));
        if (token.value.as_ulong > 128U)
                RETTOK(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(isc_lex_getmastertoken(lexer, &token,
                                              isc_tokentype_string,
                                              ISC_FALSE));
                if (inet_pton(AF_INET6, DNS_AS_STR(token), addr) != 1)
                        RETTOK(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(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));
        ok = ISC_TRUE;
        if ((options & DNS_RDATA_CHECKNAMES) != 0)
                ok = dns_name_ishostname(&name, ISC_FALSE);
        if (!ok && (options & DNS_RDATA_CHECKNAMESFAIL) != 0)
                RETTOK(DNS_R_BADNAME);
        if (!ok && callbacks != NULL)
                warn_badname(&name, lexer, callbacks);
        return (ISC_R_SUCCESS);
}

static inline isc_result_t
totext_in_a6(ARGS_TOTEXT) {
        isc_region_t sr, ar;
        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);
        REQUIRE(rdata->length != 0);

        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));
                memmove(&addr[octets], sr.base, 16 - octets);
                mask = 0xff >> (prefixlen % 8);
                addr[octets] &= mask;
                ar.base = addr;
                ar.length = sizeof(addr);
                RETERR(inet_totext(AF_INET6, &ar, target));
                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);

        UNUSED(type);
        UNUSED(rdclass);

        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, options, target));
}

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

        REQUIRE(rdata->type == 38);
        REQUIRE(rdata->rdclass == 1);
        REQUIRE(rdata->length != 0);

        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, offsets);
        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);
        REQUIRE(rdata1->length != 0);
        REQUIRE(rdata2->length != 0);

        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);

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

        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);
                memmove(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));
}

static inline isc_boolean_t
checkowner_in_a6(ARGS_CHECKOWNER) {

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

        UNUSED(type);
        UNUSED(rdclass);

        return (dns_name_ishostname(name, wildcard));
}

static inline isc_boolean_t
checknames_in_a6(ARGS_CHECKNAMES) {
        isc_region_t region;
        dns_name_t name;
        unsigned int prefixlen;

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

        UNUSED(owner);

        dns_rdata_toregion(rdata, &region);
        prefixlen = uint8_fromregion(&region);
        if (prefixlen == 0)
                return (ISC_TRUE);
        isc_region_consume(&region, 1 + 16 - prefixlen / 8);
        dns_name_init(&name, NULL);
        dns_name_fromregion(&name, &region);
        if (!dns_name_ishostname(&name, ISC_FALSE)) {
                if (bad != NULL)
                        dns_name_clone(&name, bad);
                return (ISC_FALSE);
        }
        return (ISC_TRUE);
}

static inline int
casecompare_in_a6(ARGS_COMPARE) {
        return (compare_in_a6(rdata1, rdata2));
}

#endif  /* RDATA_IN_1_A6_38_C */

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