nsec3_50.c

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/*
 * Copyright (C) 2008, 2009, 2011, 2012, 2014, 2015  Internet Systems Consortium, Inc. ("ISC")
 *
 * 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.
 */

/* $Id$ */

/*
 * Copyright (C) 2004  Nominet, Ltd.
 *
 * 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 NOMINET 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.
 */

/* RFC 5155 */

#ifndef RDATA_GENERIC_NSEC3_50_C
#define RDATA_GENERIC_NSEC3_50_C

#include <isc/iterated_hash.h>
#include <isc/base32.h>

#define RRTYPE_NSEC3_ATTRIBUTES DNS_RDATATYPEATTR_DNSSEC

static inline isc_result_t
fromtext_nsec3(ARGS_FROMTEXT) {
        isc_token_t token;
        unsigned char bm[8*1024]; /* 64k bits */
        dns_rdatatype_t covered;
        int octet;
        int window;
        unsigned int flags;
        unsigned char hashalg;
        isc_buffer_t b;

        REQUIRE(type == 50);

        UNUSED(type);
        UNUSED(rdclass);
        UNUSED(callbacks);
        UNUSED(origin);
        UNUSED(options);

        /* Hash. */
        RETERR(isc_lex_getmastertoken(lexer, &token, isc_tokentype_string,
                                      ISC_FALSE));
        RETTOK(dns_hashalg_fromtext(&hashalg, &token.value.as_textregion));
        RETERR(uint8_tobuffer(hashalg, target));

        /* Flags. */
        RETERR(isc_lex_getmastertoken(lexer, &token, isc_tokentype_number,
                                      ISC_FALSE));
        flags = token.value.as_ulong;
        if (flags > 255U)
                RETTOK(ISC_R_RANGE);
        RETERR(uint8_tobuffer(flags, target));

        /* Iterations. */
        RETERR(isc_lex_getmastertoken(lexer, &token, isc_tokentype_number,
                                      ISC_FALSE));
        if (token.value.as_ulong > 0xffffU)
                RETTOK(ISC_R_RANGE);
        RETERR(uint16_tobuffer(token.value.as_ulong, target));

        /* salt */
        RETERR(isc_lex_getmastertoken(lexer, &token, isc_tokentype_string,
                                      ISC_FALSE));
        if (token.value.as_textregion.length > (255*2))
                RETTOK(DNS_R_TEXTTOOLONG);
        if (strcmp(DNS_AS_STR(token), "-") == 0) {
                RETERR(uint8_tobuffer(0, target));
        } else {
                RETERR(uint8_tobuffer(strlen(DNS_AS_STR(token)) / 2, target));
                RETERR(isc_hex_decodestring(DNS_AS_STR(token), target));
        }

        /*
         * Next hash a single base32hex word.
         */
        RETERR(isc_lex_getmastertoken(lexer, &token, isc_tokentype_string,
                                      ISC_FALSE));
        isc_buffer_init(&b, bm, sizeof(bm));
        RETTOK(isc_base32hexnp_decodestring(DNS_AS_STR(token), &b));
        if (isc_buffer_usedlength(&b) > 0xffU)
                RETTOK(ISC_R_RANGE);
        RETERR(uint8_tobuffer(isc_buffer_usedlength(&b), target));
        RETERR(mem_tobuffer(target, &bm, isc_buffer_usedlength(&b)));

        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_nsec3(ARGS_TOTEXT) {
        isc_region_t sr;
        unsigned int i, j, k;
        unsigned int window, len;
        unsigned char hash;
        unsigned char flags;
        char buf[sizeof("TYPE65535")];
        isc_uint32_t iterations;
        isc_boolean_t first;

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

        dns_rdata_toregion(rdata, &sr);

        /* Hash */
        hash = uint8_fromregion(&sr);
        isc_region_consume(&sr, 1);
        sprintf(buf, "%u ", hash);
        RETERR(str_totext(buf, target));

        /* Flags */
        flags = uint8_fromregion(&sr);
        isc_region_consume(&sr, 1);
        sprintf(buf, "%u ", flags);
        RETERR(str_totext(buf, target));

        /* Iterations */
        iterations = uint16_fromregion(&sr);
        isc_region_consume(&sr, 2);
        sprintf(buf, "%u ", iterations);
        RETERR(str_totext(buf, target));

        /* Salt */
        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;
        } else
                RETERR(str_totext("-", target));

        if ((tctx->flags & DNS_STYLEFLAG_MULTILINE) != 0)
                RETERR(str_totext(" (", target));
        RETERR(str_totext(tctx->linebreak, target));

        /* Next hash */
        j = uint8_fromregion(&sr);
        isc_region_consume(&sr, 1);
        INSIST(j <= sr.length);

        i = sr.length;
        sr.length = j;
        RETERR(isc_base32hexnp_totext(&sr, 1, "", target));
        sr.length = i - j;

        if ((tctx->flags & DNS_STYLEFLAG_MULTILINE) == 0)
                RETERR(str_totext(" ", target));

        /* Types covered */
        first = ISC_TRUE;
        for (i = 0; i < sr.length; i += len) {
                if ((tctx->flags & DNS_STYLEFLAG_MULTILINE) != 0) {
                        RETERR(str_totext(tctx->linebreak, target));
                        first = ISC_TRUE;
                }
                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;
                                if (!first)
                                        RETERR(str_totext(" ", target));
                                first = ISC_FALSE;
                                if (dns_rdatatype_isknown(t)) {
                                        RETERR(dns_rdatatype_totext(t, target));
                                } else {
                                        sprintf(buf, "TYPE%u", t);
                                        RETERR(str_totext(buf, target));
                                }
                        }
                }
        }

        if ((tctx->flags & DNS_STYLEFLAG_MULTILINE) != 0)
                RETERR(str_totext(" )", 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), iteration(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) {
        unsigned char owner[NSEC3_MAX_HASH_LENGTH];
        isc_buffer_t buffer;
        dns_label_t label;

        REQUIRE(type == 50);

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

        /*
         * First label is a base32hex string without padding.
         */
        dns_name_getlabel(name, 0, &label);
        isc_region_consume(&label, 1);
        isc_buffer_init(&buffer, owner, sizeof(owner));
        if (isc_base32hexnp_decoderegion(&label, &buffer) == ISC_R_SUCCESS)
                return (ISC_TRUE);

        return (ISC_FALSE);
}

static inline isc_boolean_t
checknames_nsec3(ARGS_CHECKNAMES) {

        REQUIRE(rdata->type == 50);

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

        return (ISC_TRUE);
}

static inline int
casecompare_nsec3(ARGS_COMPARE) {
        return (compare_nsec3(rdata1, rdata2));
}

#endif  /* RDATA_GENERIC_NSEC3_50_C */

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