bin/dnssec/dnssectool.c

	dnssectool.c revision bd911976d51f102751848568ccf56592fd5f6d77
/*
 * Copyright (C) 2000, 2001, 2003-2005, 2007, 2009-2017  Internet Systems Consortium, Inc. ("ISC")
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 */

/*! \file */

/*%
 * DNSSEC Support Routines.
 */

#include <config.h>

#include <stdlib.h>

#ifdef _WIN32
#include <Winsock2.h>
#endif

#include <isc/base32.h>
#include <isc/buffer.h>
#include <isc/commandline.h>
#include <isc/dir.h>
#include <isc/entropy.h>
#include <isc/file.h>
#include <isc/heap.h>
#include <isc/list.h>
#include <isc/mem.h>
#include <isc/print.h>
#include <isc/string.h>
#include <isc/time.h>
#include <isc/util.h>

#include <dns/db.h>
#include <dns/dbiterator.h>
#include <dns/dnssec.h>
#include <dns/fixedname.h>
#include <dns/keyvalues.h>
#include <dns/log.h>
#include <dns/name.h>
#include <dns/nsec.h>
#include <dns/nsec3.h>
#include <dns/rdatastruct.h>
#include <dns/rdataclass.h>
#include <dns/rdataset.h>
#include <dns/rdatasetiter.h>
#include <dns/rdatatype.h>
#include <dns/result.h>
#include <dns/secalg.h>
#include <dns/time.h>

#include "dnssectool.h"

static isc_heap_t *expected_chains, *found_chains;

struct nsec3_chain_fixed {
    isc_uint8_t hash;
    isc_uint8_t salt_length;
    isc_uint8_t next_length;
    isc_uint16_t    iterations;
    /* unsigned char salt[0]; */
    /* unsigned char owner[0]; */
    /* unsigned char next[0]; */
};

extern int verbose;
extern const char *program;

typedef struct entropysource entropysource_t;

struct entropysource {
    isc_entropysource_t *source;
    isc_mem_t *mctx;
    ISC_LINK(entropysource_t) link;
};

static ISC_LIST(entropysource_t) sources;
static fatalcallback_t *fatalcallback = NULL;

void
fatal(const char *format, ...) {
    va_list args;

    fprintf(stderr, "%s: fatal: ", program);
    va_start(args, format);
    vfprintf(stderr, format, args);
    va_end(args);
    fprintf(stderr, "\n");
    if (fatalcallback != NULL)
        (*fatalcallback)();
    exit(1);
}

void
setfatalcallback(fatalcallback_t *callback) {
    fatalcallback = callback;
}

void
check_result(isc_result_t result, const char *message) {
    if (result != ISC_R_SUCCESS)
        fatal("%s: %s", message, isc_result_totext(result));
}

void
vbprintf(int level, const char *fmt, ...) {
    va_list ap;
    if (level > verbose)
        return;
    va_start(ap, fmt);
    fprintf(stderr, "%s: ", program);
    vfprintf(stderr, fmt, ap);
    va_end(ap);
}

void
version(const char *name) {
    fprintf(stderr, "%s %s\n", name, VERSION);
    exit(0);
}

void
type_format(const dns_rdatatype_t type, char *cp, unsigned int size) {
    isc_buffer_t b;
    isc_region_t r;
    isc_result_t result;

    isc_buffer_init(&b, cp, size - 1);
    result = dns_rdatatype_totext(type, &b);
    check_result(result, "dns_rdatatype_totext()");
    isc_buffer_usedregion(&b, &r);
    r.base[r.length] = 0;
}

void
sig_format(dns_rdata_rrsig_t *sig, char *cp, unsigned int size) {
    char namestr[DNS_NAME_FORMATSIZE];
    char algstr[DNS_NAME_FORMATSIZE];

    dns_name_format(&sig->signer, namestr, sizeof(namestr));
    dns_secalg_format(sig->algorithm, algstr, sizeof(algstr));
    snprintf(cp, size, "%s/%s/%d", namestr, algstr, sig->keyid);
}

void
setup_logging(isc_mem_t *mctx, isc_log_t **logp) {
    isc_result_t result;
    isc_logdestination_t destination;
    isc_logconfig_t *logconfig = NULL;
    isc_log_t *log = NULL;
    int level;

    if (verbose < 0)
        verbose = 0;
    switch (verbose) {
    case 0:
        /*
         * We want to see warnings about things like out-of-zone
         * data in the master file even when not verbose.
         */
        level = ISC_LOG_WARNING;
        break;
    case 1:
        level = ISC_LOG_INFO;
        break;
    default:
        level = ISC_LOG_DEBUG(verbose - 2 + 1);
        break;
    }

    RUNTIME_CHECK(isc_log_create(mctx, &log, &logconfig) == ISC_R_SUCCESS);
    isc_log_setcontext(log);
    dns_log_init(log);
    dns_log_setcontext(log);

    RUNTIME_CHECK(isc_log_settag(logconfig, program) == ISC_R_SUCCESS);

    /*
     * Set up a channel similar to default_stderr except:
     *  - the logging level is passed in
     *  - the program name and logging level are printed
     *  - no time stamp is printed
     */
    destination.file.stream = stderr;
    destination.file.name = NULL;
    destination.file.versions = ISC_LOG_ROLLNEVER;
    destination.file.maximum_size = 0;
    result = isc_log_createchannel(logconfig, "stderr",
                       ISC_LOG_TOFILEDESC,
                       level,
                       &destination,
                       ISC_LOG_PRINTTAG|ISC_LOG_PRINTLEVEL);
    check_result(result, "isc_log_createchannel()");

    RUNTIME_CHECK(isc_log_usechannel(logconfig, "stderr",
                     NULL, NULL) == ISC_R_SUCCESS);

    *logp = log;
}

void
cleanup_logging(isc_log_t **logp) {
    isc_log_t *log;

    REQUIRE(logp != NULL);

    log = *logp;
    if (log == NULL)
        return;
    isc_log_destroy(&log);
    isc_log_setcontext(NULL);
    dns_log_setcontext(NULL);
    logp = NULL;
}

void
setup_entropy(isc_mem_t *mctx, const char *randomfile, isc_entropy_t **ectx) {
    isc_result_t result;
    isc_entropysource_t *source = NULL;
    entropysource_t *elt;
    int usekeyboard = ISC_ENTROPY_KEYBOARDMAYBE;

    REQUIRE(ectx != NULL);

    if (*ectx == NULL) {
        result = isc_entropy_create(mctx, ectx);
        if (result != ISC_R_SUCCESS)
            fatal("could not create entropy object");
        ISC_LIST_INIT(sources);
    }

    if (randomfile != NULL && strcmp(randomfile, "keyboard") == 0) {
        usekeyboard = ISC_ENTROPY_KEYBOARDYES;
        randomfile = NULL;
    }

    result = isc_entropy_usebestsource(*ectx, &source, randomfile,
                       usekeyboard);

    if (result != ISC_R_SUCCESS)
        fatal("could not initialize entropy source: %s",
              isc_result_totext(result));

    if (source != NULL) {
        elt = isc_mem_get(mctx, sizeof(*elt));
        if (elt == NULL)
            fatal("out of memory");
        elt->source = source;
        elt->mctx = mctx;
        ISC_LINK_INIT(elt, link);
        ISC_LIST_APPEND(sources, elt, link);
    }
}

void
cleanup_entropy(isc_entropy_t **ectx) {
    entropysource_t *source;
    while (!ISC_LIST_EMPTY(sources)) {
        source = ISC_LIST_HEAD(sources);
        ISC_LIST_UNLINK(sources, source, link);
        isc_entropy_destroysource(&source->source);
        isc_mem_put(source->mctx, source, sizeof(*source));
    }
    isc_entropy_detach(ectx);
}

static isc_stdtime_t
time_units(isc_stdtime_t offset, char *suffix, const char *str) {
    switch (suffix[0]) {
        case 'Y': case 'y':
        return (offset * (365 * 24 * 3600));
        case 'M': case 'm':
        switch (suffix[1]) {
            case 'O': case 'o':
            return (offset * (30 * 24 * 3600));
            case 'I': case 'i':
            return (offset * 60);
            case '\0':
            fatal("'%s' ambiguous: use 'mi' for minutes "
                  "or 'mo' for months", str);
            default:
            fatal("time value %s is invalid", str);
        }
        /* NOTREACHED */
        break;
        case 'W': case 'w':
        return (offset * (7 * 24 * 3600));
        case 'D': case 'd':
        return (offset * (24 * 3600));
        case 'H': case 'h':
        return (offset * 3600);
        case 'S': case 's': case '\0':
        return (offset);
        default:
        fatal("time value %s is invalid", str);
    }
    /* NOTREACHED */
    return(0); /* silence compiler warning */
}

static inline isc_boolean_t
isnone(const char *str) {
    return (ISC_TF((strcasecmp(str, "none") == 0) ||
               (strcasecmp(str, "never") == 0)));
}

dns_ttl_t
strtottl(const char *str) {
    const char *orig = str;
    dns_ttl_t ttl;
    char *endp;

    if (isnone(str))
        return ((dns_ttl_t) 0);

    ttl = strtol(str, &endp, 0);
    if (ttl == 0 && endp == str)
        fatal("TTL must be numeric");
    ttl = time_units(ttl, endp, orig);
    return (ttl);
}

isc_stdtime_t
strtotime(const char *str, isc_int64_t now, isc_int64_t base,
      isc_boolean_t *setp)
{
    isc_int64_t val, offset;
    isc_result_t result;
    const char *orig = str;
    char *endp;
    size_t n;

    if (isnone(str)) {
        if (setp != NULL)
            *setp = ISC_FALSE;
        return ((isc_stdtime_t) 0);
    }

    if (setp != NULL)
        *setp = ISC_TRUE;

    if ((str[0] == '0' || str[0] == '-') && str[1] == '\0')
        return ((isc_stdtime_t) 0);

    /*
     * We accept times in the following formats:
     *   now([+-]offset)
     *   YYYYMMDD([+-]offset)
     *   YYYYMMDDhhmmss([+-]offset)
     *   [+-]offset
     */
    n = strspn(str, "0123456789");
    if ((n == 8u || n == 14u) &&
        (str[n] == '\0' || str[n] == '-' || str[n] == '+'))
    {
        char timestr[15];

        strlcpy(timestr, str, sizeof(timestr));
        timestr[n] = 0;
        if (n == 8u)
            strlcat(timestr, "000000", sizeof(timestr));
        result = dns_time64_fromtext(timestr, &val);
        if (result != ISC_R_SUCCESS)
            fatal("time value %s is invalid: %s", orig,
                  isc_result_totext(result));
        base = val;
        str += n;
    } else if (strncmp(str, "now", 3) == 0) {
        base = now;
        str += 3;
    }

    if (str[0] == '\0')
        return ((isc_stdtime_t) base);
    else if (str[0] == '+') {
        offset = strtol(str + 1, &endp, 0);
        offset = time_units((isc_stdtime_t) offset, endp, orig);
        val = base + offset;
    } else if (str[0] == '-') {
        offset = strtol(str + 1, &endp, 0);
        offset = time_units((isc_stdtime_t) offset, endp, orig);
        val = base - offset;
    } else
        fatal("time value %s is invalid", orig);

    return ((isc_stdtime_t) val);
}

dns_rdataclass_t
strtoclass(const char *str) {
    isc_textregion_t r;
    dns_rdataclass_t rdclass;
    isc_result_t ret;

    if (str == NULL)
        return dns_rdataclass_in;
    DE_CONST(str, r.base);
    r.length = strlen(str);
    ret = dns_rdataclass_fromtext(&rdclass, &r);
    if (ret != ISC_R_SUCCESS)
        fatal("unknown class %s", str);
    return (rdclass);
}

isc_result_t
try_dir(const char *dirname) {
    isc_result_t result;
    isc_dir_t d;

    isc_dir_init(&d);
    result = isc_dir_open(&d, dirname);
    if (result == ISC_R_SUCCESS) {
        isc_dir_close(&d);
    }
    return (result);
}

/*
 * Check private key version compatibility.
 */
void
check_keyversion(dst_key_t *key, char *keystr) {
    int major, minor;
    dst_key_getprivateformat(key, &major, &minor);
    INSIST(major <= DST_MAJOR_VERSION); /* invalid private key */

    if (major < DST_MAJOR_VERSION || minor < DST_MINOR_VERSION)
        fatal("Key %s has incompatible format version %d.%d, "
              "use -f to force upgrade to new version.",
              keystr, major, minor);
    if (minor > DST_MINOR_VERSION)
        fatal("Key %s has incompatible format version %d.%d, "
              "use -f to force downgrade to current version.",
              keystr, major, minor);
}

void
set_keyversion(dst_key_t *key) {
    int major, minor;
    dst_key_getprivateformat(key, &major, &minor);
    INSIST(major <= DST_MAJOR_VERSION);

    if (major != DST_MAJOR_VERSION || minor != DST_MINOR_VERSION)
        dst_key_setprivateformat(key, DST_MAJOR_VERSION,
                     DST_MINOR_VERSION);

    /*
     * If the key is from a version older than 1.3, set
     * set the creation date
     */
    if (major < 1 || (major == 1 && minor <= 2)) {
        isc_stdtime_t now;
        isc_stdtime_get(&now);
        dst_key_settime(key, DST_TIME_CREATED, now);
    }
}

isc_boolean_t
key_collision(dst_key_t *dstkey, dns_name_t *name, const char *dir,
          isc_mem_t *mctx, isc_boolean_t *exact)
{
    isc_result_t result;
    isc_boolean_t conflict = ISC_FALSE;
    dns_dnsseckeylist_t matchkeys;
    dns_dnsseckey_t *key = NULL;
    isc_uint16_t id, oldid;
    isc_uint32_t rid, roldid;
    dns_secalg_t alg;
    char filename[ISC_DIR_NAMEMAX];
    isc_buffer_t fileb;

    if (exact != NULL)
        *exact = ISC_FALSE;

    id = dst_key_id(dstkey);
    rid = dst_key_rid(dstkey);
    alg = dst_key_alg(dstkey);

    /*
     * For HMAC and Diffie Hellman just check if there is a
     * direct collision as they can't be revoked.  Additionally
     * dns_dnssec_findmatchingkeys only handles DNSKEY which is
     * not used for HMAC.
     */
    switch (alg) {
    case DST_ALG_HMACMD5:
    case DST_ALG_HMACSHA1:
    case DST_ALG_HMACSHA224:
    case DST_ALG_HMACSHA256:
    case DST_ALG_HMACSHA384:
    case DST_ALG_HMACSHA512:
    case DST_ALG_DH:
        isc_buffer_init(&fileb, filename, sizeof(filename));
        result = dst_key_buildfilename(dstkey, DST_TYPE_PRIVATE,
                           dir, &fileb);
        if (result != ISC_R_SUCCESS)
            return (ISC_TRUE);
        return (isc_file_exists(filename));
    }

    ISC_LIST_INIT(matchkeys);
    result = dns_dnssec_findmatchingkeys(name, dir, mctx, &matchkeys);
    if (result == ISC_R_NOTFOUND)
        return (ISC_FALSE);

    while (!ISC_LIST_EMPTY(matchkeys) && !conflict) {
        key = ISC_LIST_HEAD(matchkeys);
        if (dst_key_alg(key->key) != alg)
            goto next;

        oldid = dst_key_id(key->key);
        roldid = dst_key_rid(key->key);

        if (oldid == rid || roldid == id || id == oldid) {
            conflict = ISC_TRUE;
            if (id != oldid) {
                if (verbose > 1)
                    fprintf(stderr, "Key ID %d could "
                        "collide with %d\n",
                        id, oldid);
            } else {
                if (exact != NULL)
                    *exact = ISC_TRUE;
                if (verbose > 1)
                    fprintf(stderr, "Key ID %d exists\n",
                        id);
            }
        }

 next:
        ISC_LIST_UNLINK(matchkeys, key, link);
        dns_dnsseckey_destroy(mctx, &key);
    }

    /* Finish freeing the list */
    while (!ISC_LIST_EMPTY(matchkeys)) {
        key = ISC_LIST_HEAD(matchkeys);
        ISC_LIST_UNLINK(matchkeys, key, link);
        dns_dnsseckey_destroy(mctx, &key);
    }

    return (conflict);
}

isc_boolean_t
is_delegation(dns_db_t *db, dns_dbversion_t *ver, dns_name_t *origin,
          dns_name_t *name, dns_dbnode_t *node, isc_uint32_t *ttlp)
{
    dns_rdataset_t nsset;
    isc_result_t result;

    if (dns_name_equal(name, origin))
        return (ISC_FALSE);

    dns_rdataset_init(&nsset);
    result = dns_db_findrdataset(db, node, ver, dns_rdatatype_ns,
                     0, 0, &nsset, NULL);
    if (dns_rdataset_isassociated(&nsset)) {
        if (ttlp != NULL)
            *ttlp = nsset.ttl;
        dns_rdataset_disassociate(&nsset);
    }

    return (ISC_TF(result == ISC_R_SUCCESS));
}

static isc_boolean_t
goodsig(dns_name_t *origin, dns_rdata_t *sigrdata, dns_name_t *name,
    dns_rdataset_t *keyrdataset, dns_rdataset_t *rdataset, isc_mem_t *mctx)
{
    dns_rdata_dnskey_t key;
    dns_rdata_rrsig_t sig;
    dst_key_t *dstkey = NULL;
    isc_result_t result;

    result = dns_rdata_tostruct(sigrdata, &sig, NULL);
    check_result(result, "dns_rdata_tostruct()");

    for (result = dns_rdataset_first(keyrdataset);
         result == ISC_R_SUCCESS;
         result = dns_rdataset_next(keyrdataset)) {
        dns_rdata_t rdata = DNS_RDATA_INIT;
        dns_rdataset_current(keyrdataset, &rdata);
        result = dns_rdata_tostruct(&rdata, &key, NULL);
        check_result(result, "dns_rdata_tostruct()");
        result = dns_dnssec_keyfromrdata(origin, &rdata, mctx,
                         &dstkey);
        if (result != ISC_R_SUCCESS)
            return (ISC_FALSE);
        if (sig.algorithm != key.algorithm ||
            sig.keyid != dst_key_id(dstkey) ||
            !dns_name_equal(&sig.signer, origin)) {
            dst_key_free(&dstkey);
            continue;
        }
        result = dns_dnssec_verify(name, rdataset, dstkey, ISC_FALSE,
                       mctx, sigrdata);
        dst_key_free(&dstkey);
        if (result == ISC_R_SUCCESS)
            return(ISC_TRUE);
    }
    return (ISC_FALSE);
}

static isc_result_t
verifynsec(dns_db_t *db, dns_dbversion_t *ver, dns_name_t *name,
       dns_dbnode_t *node, dns_name_t *nextname)
{
    unsigned char buffer[DNS_NSEC_BUFFERSIZE];
    char namebuf[DNS_NAME_FORMATSIZE];
    char nextbuf[DNS_NAME_FORMATSIZE];
    char found[DNS_NAME_FORMATSIZE];
    dns_rdataset_t rdataset;
    dns_rdata_t rdata = DNS_RDATA_INIT;
    dns_rdata_t tmprdata = DNS_RDATA_INIT;
    dns_rdata_nsec_t nsec;
    isc_result_t result;

    dns_rdataset_init(&rdataset);
    result = dns_db_findrdataset(db, node, ver, dns_rdatatype_nsec,
                     0, 0, &rdataset, NULL);
    if (result != ISC_R_SUCCESS) {
        dns_name_format(name, namebuf, sizeof(namebuf));
        fprintf(stderr, "Missing NSEC record for %s\n", namebuf);
        goto failure;
    }

    result = dns_rdataset_first(&rdataset);
    check_result(result, "dns_rdataset_first()");

    dns_rdataset_current(&rdataset, &rdata);
    result = dns_rdata_tostruct(&rdata, &nsec, NULL);
    check_result(result, "dns_rdata_tostruct()");
    /* Check bit next name is consistent */
    if (!dns_name_equal(&nsec.next, nextname)) {
        dns_name_format(name, namebuf, sizeof(namebuf));
        dns_name_format(nextname, nextbuf, sizeof(nextbuf));
        dns_name_format(&nsec.next, found, sizeof(found));
        fprintf(stderr, "Bad NSEC record for %s, next name "
                "mismatch (expected:%s, found:%s)\n", namebuf,
                nextbuf, found);
        goto failure;
    }
    /* Check bit map is consistent */
    result = dns_nsec_buildrdata(db, ver, node, nextname, buffer,
                     &tmprdata);
    check_result(result, "dns_nsec_buildrdata()");
    if (dns_rdata_compare(&rdata, &tmprdata) != 0) {
        dns_name_format(name, namebuf, sizeof(namebuf));
        fprintf(stderr, "Bad NSEC record for %s, bit map "
                "mismatch\n", namebuf);
        goto failure;
    }
    result = dns_rdataset_next(&rdataset);
    if (result != ISC_R_NOMORE) {
        dns_name_format(name, namebuf, sizeof(namebuf));
        fprintf(stderr, "Multipe NSEC records for %s\n", namebuf);
        goto failure;

    }
    dns_rdataset_disassociate(&rdataset);
    return (ISC_R_SUCCESS);
 failure:
    if (dns_rdataset_isassociated(&rdataset))
        dns_rdataset_disassociate(&rdataset);
    return (ISC_R_FAILURE);
}

static void
check_no_rrsig(dns_db_t *db, dns_dbversion_t *ver, dns_rdataset_t *rdataset,
           dns_name_t *name, dns_dbnode_t *node)
{
    char namebuf[DNS_NAME_FORMATSIZE];
    char typebuf[80];
    dns_rdataset_t sigrdataset;
    dns_rdatasetiter_t *rdsiter = NULL;
    isc_result_t result;

    dns_rdataset_init(&sigrdataset);
    result = dns_db_allrdatasets(db, node, ver, 0, &rdsiter);
    check_result(result, "dns_db_allrdatasets()");
    for (result = dns_rdatasetiter_first(rdsiter);
         result == ISC_R_SUCCESS;
         result = dns_rdatasetiter_next(rdsiter)) {
        dns_rdatasetiter_current(rdsiter, &sigrdataset);
        if (sigrdataset.type == dns_rdatatype_rrsig &&
            sigrdataset.covers == rdataset->type)
            break;
        dns_rdataset_disassociate(&sigrdataset);
    }
    if (result == ISC_R_SUCCESS) {
        dns_name_format(name, namebuf, sizeof(namebuf));
        type_format(rdataset->type, typebuf, sizeof(typebuf));
        fprintf(stderr, "Warning: Found unexpected signatures for "
            "%s/%s\n", namebuf, typebuf);
    }
    if (dns_rdataset_isassociated(&sigrdataset))
        dns_rdataset_disassociate(&sigrdataset);
    dns_rdatasetiter_destroy(&rdsiter);
}

static isc_boolean_t
chain_compare(void *arg1, void *arg2) {
    struct nsec3_chain_fixed *e1 = arg1, *e2 = arg2;
    size_t len;

    /*
     * Do each element in turn to get a stable sort.
     */
    if (e1->hash < e2->hash)
        return (ISC_TRUE);
    if (e1->hash > e2->hash)
        return (ISC_FALSE);
    if (e1->iterations < e2->iterations)
        return (ISC_TRUE);
    if (e1->iterations > e2->iterations)
        return (ISC_FALSE);
    if (e1->salt_length < e2->salt_length)
        return (ISC_TRUE);
    if (e1->salt_length > e2->salt_length)
        return (ISC_FALSE);
    if (e1->next_length < e2->next_length)
        return (ISC_TRUE);
    if (e1->next_length > e2->next_length)
        return (ISC_FALSE);
    len = e1->salt_length + 2 * e1->next_length;
    if (memcmp(e1 + 1, e2 + 1, len) < 0)
        return (ISC_TRUE);
    return (ISC_FALSE);
}

static isc_boolean_t
chain_equal(struct nsec3_chain_fixed *e1, struct nsec3_chain_fixed *e2) {
    size_t len;

    if (e1->hash != e2->hash)
        return (ISC_FALSE);
    if (e1->iterations != e2->iterations)
        return (ISC_FALSE);
    if (e1->salt_length != e2->salt_length)
        return (ISC_FALSE);
    if (e1->next_length != e2->next_length)
        return (ISC_FALSE);
    len = e1->salt_length + 2 * e1->next_length;
    if (memcmp(e1 + 1, e2 + 1, len) != 0)
        return (ISC_FALSE);
    return (ISC_TRUE);
}

static isc_result_t
record_nsec3(const unsigned char *rawhash, const dns_rdata_nsec3_t *nsec3,
         isc_mem_t *mctx, isc_heap_t *chains)
{
    struct nsec3_chain_fixed *element;
    size_t len;
    unsigned char *cp;
    isc_result_t result;

    len = sizeof(*element) + nsec3->next_length * 2 + nsec3->salt_length;

    element = isc_mem_get(mctx, len);
    if (element == NULL)
        return (ISC_R_NOMEMORY);
    memset(element, 0, len);
    element->hash = nsec3->hash;
    element->salt_length = nsec3->salt_length;
    element->next_length = nsec3->next_length;
    element->iterations = nsec3->iterations;
    cp = (unsigned char *)(element + 1);
    memmove(cp, nsec3->salt, nsec3->salt_length);
    cp += nsec3->salt_length;
    memmove(cp, rawhash, nsec3->next_length);
    cp += nsec3->next_length;
    memmove(cp, nsec3->next, nsec3->next_length);
    result = isc_heap_insert(chains, element);
    if (result != ISC_R_SUCCESS) {
        fprintf(stderr, "isc_heap_insert failed: %s\n",
            isc_result_totext(result));
        isc_mem_put(mctx, element, len);
    }
    return (result);
}

static isc_result_t
match_nsec3(dns_name_t *name, isc_mem_t *mctx,
        dns_rdata_nsec3param_t *nsec3param, dns_rdataset_t *rdataset,
        unsigned char types[8192], unsigned int maxtype,
        unsigned char *rawhash, size_t rhsize)
{
    unsigned char cbm[8244];
    char namebuf[DNS_NAME_FORMATSIZE];
    dns_rdata_nsec3_t nsec3;
    isc_result_t result;
    unsigned int len;

    /*
     * Find matching NSEC3 record.
     */
    for (result = dns_rdataset_first(rdataset);
         result == ISC_R_SUCCESS;
         result = dns_rdataset_next(rdataset)) {
        dns_rdata_t rdata = DNS_RDATA_INIT;
        dns_rdataset_current(rdataset, &rdata);
        result = dns_rdata_tostruct(&rdata, &nsec3, NULL);
        check_result(result, "dns_rdata_tostruct()");
        if (nsec3.hash == nsec3param->hash &&
            nsec3.next_length == rhsize &&
            nsec3.iterations == nsec3param->iterations &&
            nsec3.salt_length == nsec3param->salt_length &&
            memcmp(nsec3.salt, nsec3param->salt,
               nsec3param->salt_length) == 0)
            break;
    }
    if (result != ISC_R_SUCCESS) {
        dns_name_format(name, namebuf, sizeof(namebuf));
        fprintf(stderr, "Missing NSEC3 record for %s\n", namebuf);
        return (result);
    }

    /*
     * Check the type list.
     */
    len = dns_nsec_compressbitmap(cbm, types, maxtype);
    if (nsec3.len != len || memcmp(cbm, nsec3.typebits, len) != 0) {
        dns_name_format(name, namebuf, sizeof(namebuf));
        fprintf(stderr, "Bad NSEC3 record for %s, bit map "
                "mismatch\n", namebuf);
        return (ISC_R_FAILURE);
    }

    /*
     * Record chain.
     */
    result = record_nsec3(rawhash, &nsec3, mctx, expected_chains);
    check_result(result, "record_nsec3()");

    /*
     * Make sure there is only one NSEC3 record with this set of
     * parameters.
     */
    for (result = dns_rdataset_next(rdataset);
         result == ISC_R_SUCCESS;
         result = dns_rdataset_next(rdataset)) {
        dns_rdata_t rdata = DNS_RDATA_INIT;
        dns_rdataset_current(rdataset, &rdata);
        result = dns_rdata_tostruct(&rdata, &nsec3, NULL);
        check_result(result, "dns_rdata_tostruct()");
        if (nsec3.hash == nsec3param->hash &&
            nsec3.iterations == nsec3param->iterations &&
            nsec3.salt_length == nsec3param->salt_length &&
            memcmp(nsec3.salt, nsec3param->salt,
               nsec3.salt_length) == 0) {
            dns_name_format(name, namebuf, sizeof(namebuf));
            fprintf(stderr, "Multiple NSEC3 records with the "
                "same parameter set for %s", namebuf);
            result = DNS_R_DUPLICATE;
            break;
        }
    }
    if (result != ISC_R_NOMORE)
        return (result);

    result = ISC_R_SUCCESS;
    return (result);
}

static isc_boolean_t
innsec3params(dns_rdata_nsec3_t *nsec3, dns_rdataset_t *nsec3paramset) {
    dns_rdata_nsec3param_t nsec3param;
    isc_result_t result;

    for (result = dns_rdataset_first(nsec3paramset);
         result == ISC_R_SUCCESS;
         result = dns_rdataset_next(nsec3paramset)) {
        dns_rdata_t rdata = DNS_RDATA_INIT;

        dns_rdataset_current(nsec3paramset, &rdata);
        result = dns_rdata_tostruct(&rdata, &nsec3param, NULL);
        check_result(result, "dns_rdata_tostruct()");
        if (nsec3param.flags == 0 &&
            nsec3param.hash == nsec3->hash &&
            nsec3param.iterations == nsec3->iterations &&
            nsec3param.salt_length == nsec3->salt_length &&
            memcmp(nsec3param.salt, nsec3->salt,
               nsec3->salt_length) == 0)
            return (ISC_TRUE);
    }
    return (ISC_FALSE);
}

static isc_result_t
record_found(dns_db_t *db, dns_dbversion_t *ver, isc_mem_t *mctx,
         dns_name_t *name, dns_dbnode_t *node,
         dns_rdataset_t *nsec3paramset)
{
    unsigned char owner[NSEC3_MAX_HASH_LENGTH];
    dns_rdata_nsec3_t nsec3;
    dns_rdataset_t rdataset;
    dns_label_t hashlabel;
    isc_buffer_t b;
    isc_result_t result;

    if (nsec3paramset == NULL || !dns_rdataset_isassociated(nsec3paramset))
        return (ISC_R_SUCCESS);

    dns_rdataset_init(&rdataset);
    result = dns_db_findrdataset(db, node, ver, dns_rdatatype_nsec3,
                     0, 0, &rdataset, NULL);
    if (result != ISC_R_SUCCESS)
        return (ISC_R_SUCCESS);

    dns_name_getlabel(name, 0, &hashlabel);
    isc_region_consume(&hashlabel, 1);
    isc_buffer_init(&b, owner, sizeof(owner));
    result = isc_base32hex_decoderegion(&hashlabel, &b);
    if (result != ISC_R_SUCCESS)
        goto cleanup;

    for (result = dns_rdataset_first(&rdataset);
         result == ISC_R_SUCCESS;
         result = dns_rdataset_next(&rdataset)) {
        dns_rdata_t rdata = DNS_RDATA_INIT;
        dns_rdataset_current(&rdataset, &rdata);
        result = dns_rdata_tostruct(&rdata, &nsec3, NULL);
        check_result(result, "dns_rdata_tostruct()");
        if (nsec3.next_length != isc_buffer_usedlength(&b))
            continue;
        /*
         * We only care about NSEC3 records that match a NSEC3PARAM
         * record.
         */
        if (!innsec3params(&nsec3, nsec3paramset))
            continue;

        /*
         * Record chain.
         */
        result = record_nsec3(owner, &nsec3, mctx, found_chains);
        check_result(result, "record_nsec3()");
    }

 cleanup:
    dns_rdataset_disassociate(&rdataset);
    return (ISC_R_SUCCESS);
}

static isc_boolean_t
isoptout(dns_db_t *db, dns_dbversion_t *ver, dns_name_t *origin,
     dns_rdata_t *nsec3rdata)
{
    dns_rdataset_t rdataset;
    dns_rdata_t rdata = DNS_RDATA_INIT;
    dns_rdata_nsec3_t nsec3;
    dns_rdata_nsec3param_t nsec3param;
    dns_fixedname_t fixed;
    dns_name_t *hashname;
    isc_result_t result;
    dns_dbnode_t *node = NULL;
    unsigned char rawhash[NSEC3_MAX_HASH_LENGTH];
    size_t rhsize = sizeof(rawhash);
    isc_boolean_t ret;

    result = dns_rdata_tostruct(nsec3rdata, &nsec3param, NULL);
    check_result(result, "dns_rdata_tostruct()");

    dns_fixedname_init(&fixed);
    result = dns_nsec3_hashname(&fixed, rawhash, &rhsize, origin, origin,
                    nsec3param.hash, nsec3param.iterations,
                    nsec3param.salt, nsec3param.salt_length);
    check_result(result, "dns_nsec3_hashname()");

    dns_rdataset_init(&rdataset);
    hashname = dns_fixedname_name(&fixed);
    result = dns_db_findnsec3node(db, hashname, ISC_FALSE, &node);
    if (result == ISC_R_SUCCESS)
        result = dns_db_findrdataset(db, node, ver, dns_rdatatype_nsec3,
                         0, 0, &rdataset, NULL);
    if (result != ISC_R_SUCCESS)
        return (ISC_FALSE);

    result = dns_rdataset_first(&rdataset);
    check_result(result, "dns_rdataset_first()");

    dns_rdataset_current(&rdataset, &rdata);

    result = dns_rdata_tostruct(&rdata, &nsec3, NULL);
    if (result != ISC_R_SUCCESS)
        ret = ISC_FALSE;
    else
        ret = ISC_TF((nsec3.flags & DNS_NSEC3FLAG_OPTOUT) != 0);

    if (dns_rdataset_isassociated(&rdataset))
        dns_rdataset_disassociate(&rdataset);
    if (node != NULL)
        dns_db_detachnode(db, &node);

    return (ret);
}

static isc_result_t
verifynsec3(dns_db_t *db, dns_dbversion_t *ver, dns_name_t *origin,
        isc_mem_t *mctx, dns_name_t *name, dns_rdata_t *rdata,
        isc_boolean_t delegation, isc_boolean_t empty,
        unsigned char types[8192], unsigned int maxtype)
{
    char namebuf[DNS_NAME_FORMATSIZE];
    char hashbuf[DNS_NAME_FORMATSIZE];
    dns_rdataset_t rdataset;
    dns_rdata_nsec3param_t nsec3param;
    dns_fixedname_t fixed;
    dns_name_t *hashname;
    isc_result_t result;
    dns_dbnode_t *node = NULL;
    unsigned char rawhash[NSEC3_MAX_HASH_LENGTH];
    size_t rhsize = sizeof(rawhash);
    isc_boolean_t optout;

    result = dns_rdata_tostruct(rdata, &nsec3param, NULL);
    check_result(result, "dns_rdata_tostruct()");

    if (nsec3param.flags != 0)
        return (ISC_R_SUCCESS);

    if (!dns_nsec3_supportedhash(nsec3param.hash))
        return (ISC_R_SUCCESS);

    optout = isoptout(db, ver, origin, rdata);

    dns_fixedname_init(&fixed);
    result = dns_nsec3_hashname(&fixed, rawhash, &rhsize, name, origin,
                    nsec3param.hash, nsec3param.iterations,
                    nsec3param.salt, nsec3param.salt_length);
    check_result(result, "dns_nsec3_hashname()");

    /*
     * We don't use dns_db_find() here as it works with the choosen
     * nsec3 chain and we may also be called with uncommitted data
     * from dnssec-signzone so the secure status of the zone may not
     * be up to date.
     */
    dns_rdataset_init(&rdataset);
    hashname = dns_fixedname_name(&fixed);
    result = dns_db_findnsec3node(db, hashname, ISC_FALSE, &node);
    if (result == ISC_R_SUCCESS)
        result = dns_db_findrdataset(db, node, ver, dns_rdatatype_nsec3,
                         0, 0, &rdataset, NULL);
    if (result != ISC_R_SUCCESS &&
        (!delegation || (empty && !optout) ||
         (!empty && dns_nsec_isset(types, dns_rdatatype_ds))))
    {
        dns_name_format(name, namebuf, sizeof(namebuf));
        dns_name_format(hashname, hashbuf, sizeof(hashbuf));
        fprintf(stderr, "Missing NSEC3 record for %s (%s)\n",
            namebuf, hashbuf);
    } else if (result == ISC_R_NOTFOUND &&
           delegation && (!empty || optout))
    {
        result = ISC_R_SUCCESS;
    } else if (result == ISC_R_SUCCESS) {
        result = match_nsec3(name, mctx, &nsec3param, &rdataset,
                     types, maxtype, rawhash, rhsize);
    }

    if (dns_rdataset_isassociated(&rdataset))
        dns_rdataset_disassociate(&rdataset);
    if (node != NULL)
        dns_db_detachnode(db, &node);

    return (result);
}

static isc_result_t
verifynsec3s(dns_db_t *db, dns_dbversion_t *ver, dns_name_t *origin,
         isc_mem_t *mctx, dns_name_t *name, dns_rdataset_t *nsec3paramset,
         isc_boolean_t delegation, isc_boolean_t empty,
         unsigned char types[8192], unsigned int maxtype)
{
    isc_result_t result;

    for (result = dns_rdataset_first(nsec3paramset);
         result == ISC_R_SUCCESS;
         result = dns_rdataset_next(nsec3paramset)) {
        dns_rdata_t rdata = DNS_RDATA_INIT;

        dns_rdataset_current(nsec3paramset, &rdata);
        result = verifynsec3(db, ver, origin, mctx, name, &rdata,
                     delegation, empty, types, maxtype);
        if (result != ISC_R_SUCCESS)
            break;
    }
    if (result == ISC_R_NOMORE)
        result = ISC_R_SUCCESS;
    return (result);
}

static void
verifyset(dns_db_t *db, dns_dbversion_t *ver, dns_name_t *origin,
      isc_mem_t *mctx, dns_rdataset_t *rdataset, dns_name_t *name,
      dns_dbnode_t *node, dns_rdataset_t *keyrdataset,
      unsigned char *act_algorithms, unsigned char *bad_algorithms)
{
    unsigned char set_algorithms[256];
    char namebuf[DNS_NAME_FORMATSIZE];
    char algbuf[80];
    char typebuf[80];
    dns_rdataset_t sigrdataset;
    dns_rdatasetiter_t *rdsiter = NULL;
    isc_result_t result;
    int i;

    dns_rdataset_init(&sigrdataset);
    result = dns_db_allrdatasets(db, node, ver, 0, &rdsiter);
    check_result(result, "dns_db_allrdatasets()");
    for (result = dns_rdatasetiter_first(rdsiter);
         result == ISC_R_SUCCESS;
         result = dns_rdatasetiter_next(rdsiter)) {
        dns_rdatasetiter_current(rdsiter, &sigrdataset);
        if (sigrdataset.type == dns_rdatatype_rrsig &&
            sigrdataset.covers == rdataset->type)
            break;
        dns_rdataset_disassociate(&sigrdataset);
    }
    if (result != ISC_R_SUCCESS) {
        dns_name_format(name, namebuf, sizeof(namebuf));
        type_format(rdataset->type, typebuf, sizeof(typebuf));
        fprintf(stderr, "No signatures for %s/%s\n", namebuf, typebuf);
        for (i = 0; i < 256; i++)
            if (act_algorithms[i] != 0)
                bad_algorithms[i] = 1;
        dns_rdatasetiter_destroy(&rdsiter);
        return;
    }

    memset(set_algorithms, 0, sizeof(set_algorithms));
    for (result = dns_rdataset_first(&sigrdataset);
         result == ISC_R_SUCCESS;
         result = dns_rdataset_next(&sigrdataset)) {
        dns_rdata_t rdata = DNS_RDATA_INIT;
        dns_rdata_rrsig_t sig;

        dns_rdataset_current(&sigrdataset, &rdata);
        result = dns_rdata_tostruct(&rdata, &sig, NULL);
        check_result(result, "dns_rdata_tostruct()");
        if (rdataset->ttl != sig.originalttl) {
            dns_name_format(name, namebuf, sizeof(namebuf));
            type_format(rdataset->type, typebuf, sizeof(typebuf));
            fprintf(stderr, "TTL mismatch for %s %s keytag %u\n",
                namebuf, typebuf, sig.keyid);
            continue;
        }
        if ((set_algorithms[sig.algorithm] != 0) ||
            (act_algorithms[sig.algorithm] == 0))
            continue;
        if (goodsig(origin, &rdata, name, keyrdataset, rdataset, mctx))
            set_algorithms[sig.algorithm] = 1;
    }
    dns_rdatasetiter_destroy(&rdsiter);
    if (memcmp(set_algorithms, act_algorithms, sizeof(set_algorithms))) {
        dns_name_format(name, namebuf, sizeof(namebuf));
        type_format(rdataset->type, typebuf, sizeof(typebuf));
        for (i = 0; i < 256; i++)
            if ((act_algorithms[i] != 0) &&
                (set_algorithms[i] == 0)) {
                dns_secalg_format(i, algbuf, sizeof(algbuf));
                fprintf(stderr, "No correct %s signature for "
                    "%s %s\n", algbuf, namebuf, typebuf);
                bad_algorithms[i] = 1;
            }
    }
    dns_rdataset_disassociate(&sigrdataset);
}

static isc_result_t
verifynode(dns_db_t *db, dns_dbversion_t *ver, dns_name_t *origin,
       isc_mem_t *mctx, dns_name_t *name, dns_dbnode_t *node,
       isc_boolean_t delegation, dns_rdataset_t *keyrdataset,
       unsigned char *act_algorithms, unsigned char *bad_algorithms,
       dns_rdataset_t *nsecset, dns_rdataset_t *nsec3paramset,
       dns_name_t *nextname)
{
    unsigned char types[8192];
    unsigned int maxtype = 0;
    dns_rdataset_t rdataset; dns_rdatasetiter_t *rdsiter = NULL;
    isc_result_t result, tresult;

    memset(types, 0, sizeof(types));
    result = dns_db_allrdatasets(db, node, ver, 0, &rdsiter);
    check_result(result, "dns_db_allrdatasets()");
    result = dns_rdatasetiter_first(rdsiter);
    dns_rdataset_init(&rdataset);
    while (result == ISC_R_SUCCESS) {
        dns_rdatasetiter_current(rdsiter, &rdataset);
        /*
         * If we are not at a delegation then everything should be
         * signed.  If we are at a delegation then only the DS set
         * is signed.  The NS set is not signed at a delegation but
         * its existance is recorded in the bit map.  Anything else
         * other than NSEC and DS is not signed at a delegation.
         */
        if (rdataset.type != dns_rdatatype_rrsig &&
            rdataset.type != dns_rdatatype_dnskey &&
            (!delegation || rdataset.type == dns_rdatatype_ds ||
             rdataset.type == dns_rdatatype_nsec)) {
            verifyset(db, ver, origin, mctx, &rdataset,
                  name, node, keyrdataset,
                  act_algorithms, bad_algorithms);
            dns_nsec_setbit(types, rdataset.type, 1);
            if (rdataset.type > maxtype)
                maxtype = rdataset.type;
        } else if (rdataset.type != dns_rdatatype_rrsig &&
               rdataset.type != dns_rdatatype_dnskey) {
            if (rdataset.type == dns_rdatatype_ns)
                dns_nsec_setbit(types, rdataset.type, 1);
            check_no_rrsig(db, ver, &rdataset, name, node);
        } else
            dns_nsec_setbit(types, rdataset.type, 1);
        dns_rdataset_disassociate(&rdataset);
        result = dns_rdatasetiter_next(rdsiter);
    }
    if (result != ISC_R_NOMORE)
        fatal("rdataset iteration failed: %s",
              isc_result_totext(result));
    dns_rdatasetiter_destroy(&rdsiter);

    result = ISC_R_SUCCESS;

    if (nsecset != NULL && dns_rdataset_isassociated(nsecset))
        result = verifynsec(db, ver, name, node, nextname);

    if (nsec3paramset != NULL && dns_rdataset_isassociated(nsec3paramset)) {
        tresult = verifynsec3s(db, ver, origin, mctx, name,
                       nsec3paramset, delegation, ISC_FALSE,
                       types, maxtype);
        if (result == ISC_R_SUCCESS && tresult != ISC_R_SUCCESS)
            result = tresult;
    }
    return (result);
}

static isc_boolean_t
is_empty(dns_db_t *db, dns_dbversion_t *ver, dns_dbnode_t *node) {
    dns_rdatasetiter_t *rdsiter = NULL;
    isc_result_t result;

    result = dns_db_allrdatasets(db, node, ver, 0, &rdsiter);
    check_result(result, "dns_db_allrdatasets()");
    result = dns_rdatasetiter_first(rdsiter);
    dns_rdatasetiter_destroy(&rdsiter);
    if (result == ISC_R_NOMORE)
        return (ISC_TRUE);
    return (ISC_FALSE);
}

static void
check_no_nsec(dns_name_t *name, dns_dbnode_t *node, dns_db_t *db,
          dns_dbversion_t *ver)
{
    dns_rdataset_t rdataset;
    isc_result_t result;

    dns_rdataset_init(&rdataset);
    result = dns_db_findrdataset(db, node, ver, dns_rdatatype_nsec,
                     0, 0, &rdataset, NULL);
    if (result != ISC_R_NOTFOUND) {
        char namebuf[DNS_NAME_FORMATSIZE];
        dns_name_format(name, namebuf, sizeof(namebuf));
        fatal("unexpected NSEC RRset at %s\n", namebuf);
    }

    if (dns_rdataset_isassociated(&rdataset))
        dns_rdataset_disassociate(&rdataset);
}

static isc_boolean_t
newchain(const struct nsec3_chain_fixed *first,
     const struct nsec3_chain_fixed *e)
{
    if (first->hash != e->hash ||
        first->iterations != e->iterations ||
        first->salt_length != e->salt_length ||
        first->next_length != e->next_length ||
        memcmp(first + 1, e + 1, first->salt_length) != 0)
        return (ISC_TRUE);
    return (ISC_FALSE);
}

static void
free_element(isc_mem_t *mctx, struct nsec3_chain_fixed *e) {
    size_t len;

    len = sizeof(*e) + e->salt_length + 2 * e->next_length;
    isc_mem_put(mctx, e, len);
}

static isc_boolean_t
checknext(const struct nsec3_chain_fixed *first,
      const struct nsec3_chain_fixed *e)
{
    char buf[512];
    const unsigned char *d1 = (const unsigned char *)(first + 1);
    const unsigned char *d2 = (const unsigned char *)(e + 1);
    isc_buffer_t b;
    isc_region_t sr;

    d1 += first->salt_length + first->next_length;
    d2 += e->salt_length;

    if (memcmp(d1, d2, first->next_length) == 0)
        return (ISC_TRUE);

    DE_CONST(d1 - first->next_length, sr.base);
    sr.length = first->next_length;
    isc_buffer_init(&b, buf, sizeof(buf));
    isc_base32hex_totext(&sr, 1, "", &b);
    fprintf(stderr, "Break in NSEC3 chain at: %.*s\n",
        (int) isc_buffer_usedlength(&b), buf);

    DE_CONST(d1, sr.base);
    sr.length = first->next_length;
    isc_buffer_init(&b, buf, sizeof(buf));
    isc_base32hex_totext(&sr, 1, "", &b);
    fprintf(stderr, "Expected: %.*s\n", (int) isc_buffer_usedlength(&b),
        buf);

    DE_CONST(d2, sr.base);
    sr.length = first->next_length;
    isc_buffer_init(&b, buf, sizeof(buf));
    isc_base32hex_totext(&sr, 1, "", &b);
    fprintf(stderr, "Found: %.*s\n", (int) isc_buffer_usedlength(&b), buf);

    return (ISC_FALSE);
}

#define EXPECTEDANDFOUND "Expected and found NSEC3 chains not equal\n"

static isc_result_t
verify_nsec3_chains(isc_mem_t *mctx) {
    isc_result_t result = ISC_R_SUCCESS;
    struct nsec3_chain_fixed *e, *f = NULL;
    struct nsec3_chain_fixed *first = NULL, *prev = NULL;

    while ((e = isc_heap_element(expected_chains, 1)) != NULL) {
        isc_heap_delete(expected_chains, 1);
        if (f == NULL)
            f = isc_heap_element(found_chains, 1);
        if (f != NULL) {
            isc_heap_delete(found_chains, 1);

            /*
             * Check that they match.
             */
            if (chain_equal(e, f)) {
                free_element(mctx, f);
                f = NULL;
            } else {
                if (result == ISC_R_SUCCESS)
                    fprintf(stderr, EXPECTEDANDFOUND);
                result = ISC_R_FAILURE;
                /*
                 * Attempt to resync found_chain.
                 */
                while (f != NULL && !chain_compare(e, f)) {
                    free_element(mctx, f);
                    f = isc_heap_element(found_chains, 1);
                    if (f != NULL)
                        isc_heap_delete(found_chains, 1);
                    if (f != NULL && chain_equal(e, f)) {
                        free_element(mctx, f);
                        f = NULL;
                        break;
                    }
                }
            }
        } else if (result == ISC_R_SUCCESS) {
            fprintf(stderr, EXPECTEDANDFOUND);
            result = ISC_R_FAILURE;
        }
        if (first == NULL || newchain(first, e)) {
            if (prev != NULL) {
                if (!checknext(prev, first))
                    result = ISC_R_FAILURE;
                if (prev != first)
                    free_element(mctx, prev);
            }
            if (first != NULL)
                free_element(mctx, first);
            prev = first = e;
            continue;
        }
        if (!checknext(prev, e))
            result = ISC_R_FAILURE;
        if (prev != first)
            free_element(mctx, prev);
        prev = e;
    }
    if (prev != NULL) {
        if (!checknext(prev, first))
            result = ISC_R_FAILURE;
        if (prev != first)
            free_element(mctx, prev);
    }
    if (first != NULL)
        free_element(mctx, first);
    do {
        if (f != NULL) {
            if (result == ISC_R_SUCCESS) {
                fprintf(stderr, EXPECTEDANDFOUND);
                result = ISC_R_FAILURE;
            }
            free_element(mctx, f);
        }
        f = isc_heap_element(found_chains, 1);
        if (f != NULL)
            isc_heap_delete(found_chains, 1);
    } while (f != NULL);

    return (result);
}

static isc_result_t
verifyemptynodes(dns_db_t *db, dns_dbversion_t *ver, dns_name_t *origin,
         isc_mem_t *mctx, dns_name_t *name, dns_name_t *prevname,
         isc_boolean_t isdelegation, dns_rdataset_t *nsec3paramset)
{
    dns_namereln_t reln;
    int order;
    unsigned int labels, nlabels, i;
    dns_name_t suffix;
    isc_result_t result = ISC_R_SUCCESS, tresult;

    reln = dns_name_fullcompare(prevname, name, &order, &labels);
    if (order >= 0)
        return (result);

    nlabels = dns_name_countlabels(name);

    if (reln == dns_namereln_commonancestor ||
        reln == dns_namereln_contains) {
        dns_name_init(&suffix, NULL);
        for (i = labels + 1; i < nlabels; i++) {
            dns_name_getlabelsequence(name, nlabels - i, i,
                          &suffix);
            if (nsec3paramset != NULL &&
                 dns_rdataset_isassociated(nsec3paramset)) {
                tresult = verifynsec3s(db, ver, origin, mctx,
                               &suffix, nsec3paramset,
                               isdelegation, ISC_TRUE,
                               NULL, 0);
                if (result == ISC_R_SUCCESS &&
                    tresult != ISC_R_SUCCESS)
                    result = tresult;
            }
        }
    }
    return (result);
}

/*%
 * Verify that certain things are sane:
 *
 *   The apex has a DNSKEY record with at least one KSK, and at least
 *   one ZSK if the -x flag was not used.
 *
 *   The DNSKEY record was signed with at least one of the KSKs in this
 *   set.
 *
 *   The rest of the zone was signed with at least one of the ZSKs
 *   present in the DNSKEY RRSET.
 */
void
verifyzone(dns_db_t *db, dns_dbversion_t *ver,
       dns_name_t *origin, isc_mem_t *mctx,
       isc_boolean_t ignore_kskflag, isc_boolean_t keyset_kskonly)
{
    char algbuf[80];
    dns_dbiterator_t *dbiter = NULL;
    dns_dbnode_t *node = NULL, *nextnode = NULL;
    dns_fixedname_t fname, fnextname, fprevname, fzonecut;
    dns_name_t *name, *nextname, *prevname, *zonecut;
    dns_rdata_dnskey_t dnskey;
    dns_rdata_t rdata = DNS_RDATA_INIT;
    dns_rdataset_t keyset, soaset;
    dns_rdataset_t keysigs, soasigs;
    dns_rdataset_t nsecset, nsecsigs;
    dns_rdataset_t nsec3paramset, nsec3paramsigs;
    int i;
    isc_boolean_t done = ISC_FALSE;
    isc_boolean_t first = ISC_TRUE;
    isc_boolean_t goodksk = ISC_FALSE;
    isc_boolean_t goodzsk = ISC_FALSE;
    isc_result_t result, vresult = ISC_R_UNSET;
    unsigned char revoked_ksk[256];
    unsigned char revoked_zsk[256];
    unsigned char standby_ksk[256];
    unsigned char standby_zsk[256];
    unsigned char ksk_algorithms[256];
    unsigned char zsk_algorithms[256];
    unsigned char bad_algorithms[256];
    unsigned char act_algorithms[256];

    result = isc_heap_create(mctx, chain_compare, NULL, 1024,
                 &expected_chains);
    check_result(result, "isc_heap_create()");
    result = isc_heap_create(mctx, chain_compare, NULL, 1024,
                 &found_chains);
    check_result(result, "isc_heap_create()");

    result = dns_db_findnode(db, origin, ISC_FALSE, &node);
    if (result != ISC_R_SUCCESS)
        fatal("failed to find the zone's origin: %s",
              isc_result_totext(result));

    dns_rdataset_init(&keyset);
    dns_rdataset_init(&keysigs);
    dns_rdataset_init(&soaset);
    dns_rdataset_init(&soasigs);
    dns_rdataset_init(&nsecset);
    dns_rdataset_init(&nsecsigs);
    dns_rdataset_init(&nsec3paramset);
    dns_rdataset_init(&nsec3paramsigs);
    result = dns_db_findrdataset(db, node, ver, dns_rdatatype_dnskey,
                     0, 0, &keyset, &keysigs);
    if (result != ISC_R_SUCCESS)
        fatal("Zone contains no DNSSEC keys\n");

    result = dns_db_findrdataset(db, node, ver, dns_rdatatype_soa,
                     0, 0, &soaset, &soasigs);
    if (result != ISC_R_SUCCESS)
        fatal("Zone contains no SOA record\n");

    result = dns_db_findrdataset(db, node, ver, dns_rdatatype_nsec,
                     0, 0, &nsecset, &nsecsigs);
    if (result != ISC_R_SUCCESS && result != ISC_R_NOTFOUND)
        fatal("NSEC lookup failed\n");

    result = dns_db_findrdataset(db, node, ver, dns_rdatatype_nsec3param,
                     0, 0, &nsec3paramset, &nsec3paramsigs);
    if (result != ISC_R_SUCCESS && result != ISC_R_NOTFOUND)
        fatal("NSEC3PARAM lookup failed\n");

    if (!dns_rdataset_isassociated(&keysigs))
        fatal("DNSKEY is not signed (keys offline or inactive?)\n");

    if (!dns_rdataset_isassociated(&soasigs))
        fatal("SOA is not signed (keys offline or inactive?)\n");

    if (dns_rdataset_isassociated(&nsecset) &&
        !dns_rdataset_isassociated(&nsecsigs))
        fatal("NSEC is not signed (keys offline or inactive?)\n");

    if (dns_rdataset_isassociated(&nsec3paramset) &&
        !dns_rdataset_isassociated(&nsec3paramsigs))
        fatal("NSEC3PARAM is not signed (keys offline or inactive?)\n");

    if (!dns_rdataset_isassociated(&nsecset) &&
        !dns_rdataset_isassociated(&nsec3paramset))
        fatal("No valid NSEC/NSEC3 chain for testing\n");

    dns_db_detachnode(db, &node);

    memset(revoked_ksk, 0, sizeof(revoked_ksk));
    memset(revoked_zsk, 0, sizeof(revoked_zsk));
    memset(standby_ksk, 0, sizeof(standby_ksk));
    memset(standby_zsk, 0, sizeof(standby_zsk));
    memset(ksk_algorithms, 0, sizeof(ksk_algorithms));
    memset(zsk_algorithms, 0, sizeof(zsk_algorithms));
    memset(bad_algorithms, 0, sizeof(bad_algorithms));
    memset(act_algorithms, 0, sizeof(act_algorithms));

    /*
     * Check that the DNSKEY RR has at least one self signing KSK
     * and one ZSK per algorithm in it (or, if -x was used, one
     * self-signing KSK).
     */
    for (result = dns_rdataset_first(&keyset);
         result == ISC_R_SUCCESS;
         result = dns_rdataset_next(&keyset)) {
        dns_rdataset_current(&keyset, &rdata);
        result = dns_rdata_tostruct(&rdata, &dnskey, NULL);
        check_result(result, "dns_rdata_tostruct");

        if ((dnskey.flags & DNS_KEYOWNER_ZONE) == 0)
            ;
        else if ((dnskey.flags & DNS_KEYFLAG_REVOKE) != 0) {
            if ((dnskey.flags & DNS_KEYFLAG_KSK) != 0 &&
                !dns_dnssec_selfsigns(&rdata, origin, &keyset,
                          &keysigs, ISC_FALSE,
                          mctx)) {
                char namebuf[DNS_NAME_FORMATSIZE];
                char buffer[1024];
                isc_buffer_t buf;

                dns_name_format(origin, namebuf,
                        sizeof(namebuf));
                isc_buffer_init(&buf, buffer, sizeof(buffer));
                result = dns_rdata_totext(&rdata, NULL, &buf);
                check_result(result, "dns_rdata_totext");
                fatal("revoked KSK is not self signed:\n"
                      "%s DNSKEY %.*s", namebuf,
                      (int)isc_buffer_usedlength(&buf), buffer);
            }
            if ((dnskey.flags & DNS_KEYFLAG_KSK) != 0 &&
                 revoked_ksk[dnskey.algorithm] != 255)
                revoked_ksk[dnskey.algorithm]++;
            else if ((dnskey.flags & DNS_KEYFLAG_KSK) == 0 &&
                 revoked_zsk[dnskey.algorithm] != 255)
                revoked_zsk[dnskey.algorithm]++;
        } else if ((dnskey.flags & DNS_KEYFLAG_KSK) != 0) {
            if (dns_dnssec_selfsigns(&rdata, origin, &keyset,
                         &keysigs, ISC_FALSE, mctx)) {
                if (ksk_algorithms[dnskey.algorithm] != 255)
                    ksk_algorithms[dnskey.algorithm]++;
                goodksk = ISC_TRUE;
            } else {
                if (standby_ksk[dnskey.algorithm] != 255)
                    standby_ksk[dnskey.algorithm]++;
            }
        } else if (dns_dnssec_selfsigns(&rdata, origin, &keyset,
                        &keysigs, ISC_FALSE, mctx)) {
            if (zsk_algorithms[dnskey.algorithm] != 255)
                zsk_algorithms[dnskey.algorithm]++;
            goodzsk = ISC_TRUE;
        } else if (dns_dnssec_signs(&rdata, origin, &soaset,
                        &soasigs, ISC_FALSE, mctx)) {
            if (zsk_algorithms[dnskey.algorithm] != 255)
                zsk_algorithms[dnskey.algorithm]++;
        } else {
            if (standby_zsk[dnskey.algorithm] != 255)
                standby_zsk[dnskey.algorithm]++;
        }
        dns_rdata_freestruct(&dnskey);
        dns_rdata_reset(&rdata);
    }
    dns_rdataset_disassociate(&keysigs);
    dns_rdataset_disassociate(&soaset);
    dns_rdataset_disassociate(&soasigs);
    if (dns_rdataset_isassociated(&nsecsigs))
        dns_rdataset_disassociate(&nsecsigs);
    if (dns_rdataset_isassociated(&nsec3paramsigs))
        dns_rdataset_disassociate(&nsec3paramsigs);

    if (ignore_kskflag ) {
        if (!goodksk && !goodzsk)
            fatal("No self-signed DNSKEY found.");
    } else if (!goodksk)
        fatal("No self-signed KSK DNSKEY found.  Supply an active\n"
              "key with the KSK flag set, or use '-P'.");

    fprintf(stderr, "Verifying the zone using the following algorithms:");
    for (i = 0; i < 256; i++) {
        if (ignore_kskflag)
            act_algorithms[i] = (ksk_algorithms[i] != 0 ||
                         zsk_algorithms[i] != 0) ? 1 : 0;
        else
            act_algorithms[i] = ksk_algorithms[i] != 0 ? 1 : 0;
        if (act_algorithms[i] != 0) {
            dns_secalg_format(i, algbuf, sizeof(algbuf));
            fprintf(stderr, " %s", algbuf);
        }
    }
    fprintf(stderr, ".\n");

    if (!ignore_kskflag && !keyset_kskonly) {
        for (i = 0; i < 256; i++) {
            /*
             * The counts should both be zero or both be non-zero.
             * Mark the algorithm as bad if this is not met.
             */
            if ((ksk_algorithms[i] != 0) ==
                (zsk_algorithms[i] != 0))
                continue;
            dns_secalg_format(i, algbuf, sizeof(algbuf));
            fprintf(stderr, "Missing %s for algorithm %s\n",
                (ksk_algorithms[i] != 0)
                   ? "ZSK"
                   : "self-signed KSK",
                algbuf);
            bad_algorithms[i] = 1;
        }
    }

    /*
     * Check that all the other records were signed by keys that are
     * present in the DNSKEY RRSET.
     */

    dns_fixedname_init(&fname);
    name = dns_fixedname_name(&fname);
    dns_fixedname_init(&fnextname);
    nextname = dns_fixedname_name(&fnextname);
    dns_fixedname_init(&fprevname);
    prevname = NULL;
    dns_fixedname_init(&fzonecut);
    zonecut = NULL;

    result = dns_db_createiterator(db, DNS_DB_NONSEC3, &dbiter);
    check_result(result, "dns_db_createiterator()");

    result = dns_dbiterator_first(dbiter);
    check_result(result, "dns_dbiterator_first()");

    while (!done) {
        isc_boolean_t isdelegation = ISC_FALSE;

        result = dns_dbiterator_current(dbiter, &node, name);
        check_dns_dbiterator_current(result);
        if (!dns_name_issubdomain(name, origin)) {
            check_no_nsec(name, node, db, ver);
            dns_db_detachnode(db, &node);
            result = dns_dbiterator_next(dbiter);
            if (result == ISC_R_NOMORE)
                done = ISC_TRUE;
            else
                check_result(result, "dns_dbiterator_next()");
            continue;
        }
        if (is_delegation(db, ver, origin, name, node, NULL)) {
            zonecut = dns_fixedname_name(&fzonecut);
            dns_name_copy(name, zonecut, NULL);
            isdelegation = ISC_TRUE;
        }
        nextnode = NULL;
        result = dns_dbiterator_next(dbiter);
        while (result == ISC_R_SUCCESS) {
            result = dns_dbiterator_current(dbiter, &nextnode,
                            nextname);
            check_dns_dbiterator_current(result);
            if (!dns_name_issubdomain(nextname, origin) ||
                (zonecut != NULL &&
                 dns_name_issubdomain(nextname, zonecut)))
            {
                check_no_nsec(nextname, nextnode, db, ver);
                dns_db_detachnode(db, &nextnode);
                result = dns_dbiterator_next(dbiter);
                continue;
            }
            if (is_empty(db, ver, nextnode)) {
                dns_db_detachnode(db, &nextnode);
                result = dns_dbiterator_next(dbiter);
                continue;
            }
            dns_db_detachnode(db, &nextnode);
            break;
        }
        if (result == ISC_R_NOMORE) {
            done = ISC_TRUE;
            nextname = origin;
        } else if (result != ISC_R_SUCCESS)
            fatal("iterating through the database failed: %s",
                  isc_result_totext(result));
        result = verifynode(db, ver, origin, mctx, name, node,
                    isdelegation, &keyset, act_algorithms,
                    bad_algorithms, &nsecset, &nsec3paramset,
                    nextname);
        if (vresult == ISC_R_UNSET)
            vresult = ISC_R_SUCCESS;
        if (vresult == ISC_R_SUCCESS && result != ISC_R_SUCCESS)
            vresult = result;
        if (prevname != NULL) {
            result = verifyemptynodes(db, ver, origin, mctx, name,
                          prevname, isdelegation,
                          &nsec3paramset);
        } else
            prevname = dns_fixedname_name(&fprevname);
        dns_name_copy(name, prevname, NULL);
        if (vresult == ISC_R_SUCCESS && result != ISC_R_SUCCESS)
            vresult = result;
        dns_db_detachnode(db, &node);
    }

    dns_dbiterator_destroy(&dbiter);

    result = dns_db_createiterator(db, DNS_DB_NSEC3ONLY, &dbiter);
    check_result(result, "dns_db_createiterator()");

    for (result = dns_dbiterator_first(dbiter);
         result == ISC_R_SUCCESS;
         result = dns_dbiterator_next(dbiter) ) {
        result = dns_dbiterator_current(dbiter, &node, name);
        check_dns_dbiterator_current(result);
        result = verifynode(db, ver, origin, mctx, name, node,
                    ISC_FALSE, &keyset, act_algorithms,
                    bad_algorithms, NULL, NULL, NULL);
        check_result(result, "verifynode");
        record_found(db, ver, mctx, name, node, &nsec3paramset);
        dns_db_detachnode(db, &node);
    }
    dns_dbiterator_destroy(&dbiter);

    dns_rdataset_disassociate(&keyset);
    if (dns_rdataset_isassociated(&nsecset))
        dns_rdataset_disassociate(&nsecset);
    if (dns_rdataset_isassociated(&nsec3paramset))
        dns_rdataset_disassociate(&nsec3paramset);

    result = verify_nsec3_chains(mctx);
    if (vresult == ISC_R_UNSET)
        vresult = ISC_R_SUCCESS;
    if (result != ISC_R_SUCCESS && vresult == ISC_R_SUCCESS)
        vresult = result;
    isc_heap_destroy(&expected_chains);
    isc_heap_destroy(&found_chains);

    /*
     * If we made it this far, we have what we consider a properly signed
     * zone.  Set the good flag.
     */
    for (i = 0; i < 256; i++) {
        if (bad_algorithms[i] != 0) {
            if (first)
                fprintf(stderr, "The zone is not fully signed "
                    "for the following algorithms:");
            dns_secalg_format(i, algbuf, sizeof(algbuf));
            fprintf(stderr, " %s", algbuf);
            first = ISC_FALSE;
        }
    }
    if (!first) {
        fprintf(stderr, ".\n");
        fatal("DNSSEC completeness test failed.");
    }

    if (vresult != ISC_R_SUCCESS)
        fatal("DNSSEC completeness test failed (%s).",
              dns_result_totext(vresult));

    if (goodksk || ignore_kskflag) {
        /*
         * Print the success summary.
         */
        fprintf(stderr, "Zone fully signed:\n");
        for (i = 0; i < 256; i++) {
            if ((ksk_algorithms[i] != 0) ||
                (standby_ksk[i] != 0) ||
                (revoked_ksk[i] != 0) ||
                (zsk_algorithms[i] != 0) ||
                (standby_zsk[i] != 0) ||
                (revoked_zsk[i] != 0)) {
                dns_secalg_format(i, algbuf, sizeof(algbuf));
                fprintf(stderr, "Algorithm: %s: KSKs: "
                    "%u active, %u stand-by, %u revoked\n",
                    algbuf, ksk_algorithms[i],
                    standby_ksk[i], revoked_ksk[i]);
                fprintf(stderr, "%*sZSKs: "
                    "%u active, %u %s, %u revoked\n",
                    (int) strlen(algbuf) + 13, "",
                    zsk_algorithms[i],
                    standby_zsk[i],
                    keyset_kskonly ? "present" : "stand-by",
                    revoked_zsk[i]);
            }
        }
    }
}

isc_boolean_t
isoptarg(const char *arg, char **argv, void(*usage)(void)) {
    if (!strcasecmp(isc_commandline_argument, arg)) {
        if (argv[isc_commandline_index] == NULL) {
            fprintf(stderr, "%s: missing argument -%c %s\n",
                program, isc_commandline_option,
                isc_commandline_argument);
            usage();
        }
        isc_commandline_argument = argv[isc_commandline_index];
        /* skip to next arguement */
        isc_commandline_index++;
        return (ISC_TRUE);
    }
    return (ISC_FALSE);
}

#ifdef _WIN32
void
InitSockets(void) {
    WORD wVersionRequested;
    WSADATA wsaData;
    int err;

    wVersionRequested = MAKEWORD(2, 0);

    err = WSAStartup( wVersionRequested, &wsaData );
    if (err != 0) {
        fprintf(stderr, "WSAStartup() failed: %d\n", err);
        exit(1);
    }
}

void
DestroySockets(void) {
    WSACleanup();
}
#endif