lib/dns/dnssec.c

	dnssec.c revision e8831e51c162f5961fcf1d89f68acd9336cf8a83
/*
 * Copyright (C) 2004-2009  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: dnssec.c,v 1.108 2009/10/27 03:59:45 each Exp $
 */

/*! \file */

#include <config.h>

#include <stdlib.h>

#include <isc/buffer.h>
#include <isc/dir.h>
#include <isc/mem.h>
#include <isc/serial.h>
#include <isc/string.h>
#include <isc/util.h>

#include <dns/db.h>
#include <dns/diff.h>
#include <dns/dnssec.h>
#include <dns/fixedname.h>
#include <dns/keyvalues.h>
#include <dns/message.h>
#include <dns/rdata.h>
#include <dns/rdatalist.h>
#include <dns/rdataset.h>
#include <dns/rdatastruct.h>
#include <dns/result.h>
#include <dns/tsig.h>       /* for DNS_TSIG_FUDGE */

#include <dst/result.h>

#define is_response(msg) (msg->flags & DNS_MESSAGEFLAG_QR)

#define RETERR(x) do { \
    result = (x); \
    if (result != ISC_R_SUCCESS) \
        goto failure; \
    } while (0)


#define TYPE_SIGN 0
#define TYPE_VERIFY 1

static isc_result_t
digest_callback(void *arg, isc_region_t *data);

static int
rdata_compare_wrapper(const void *rdata1, const void *rdata2);

static isc_result_t
rdataset_to_sortedarray(dns_rdataset_t *set, isc_mem_t *mctx,
            dns_rdata_t **rdata, int *nrdata);

static isc_result_t
digest_callback(void *arg, isc_region_t *data) {
    dst_context_t *ctx = arg;

    return (dst_context_adddata(ctx, data));
}

/*
 * Make qsort happy.
 */
static int
rdata_compare_wrapper(const void *rdata1, const void *rdata2) {
    return (dns_rdata_compare((const dns_rdata_t *)rdata1,
                  (const dns_rdata_t *)rdata2));
}

/*
 * Sort the rdataset into an array.
 */
static isc_result_t
rdataset_to_sortedarray(dns_rdataset_t *set, isc_mem_t *mctx,
            dns_rdata_t **rdata, int *nrdata)
{
    isc_result_t ret;
    int i = 0, n;
    dns_rdata_t *data;
    dns_rdataset_t rdataset;

    n = dns_rdataset_count(set);

    data = isc_mem_get(mctx, n * sizeof(dns_rdata_t));
    if (data == NULL)
        return (ISC_R_NOMEMORY);

    dns_rdataset_init(&rdataset);
    dns_rdataset_clone(set, &rdataset);
    ret = dns_rdataset_first(&rdataset);
    if (ret != ISC_R_SUCCESS) {
        dns_rdataset_disassociate(&rdataset);
        isc_mem_put(mctx, data, n * sizeof(dns_rdata_t));
        return (ret);
    }

    /*
     * Put them in the array.
     */
    do {
        dns_rdata_init(&data[i]);
        dns_rdataset_current(&rdataset, &data[i++]);
    } while (dns_rdataset_next(&rdataset) == ISC_R_SUCCESS);

    /*
     * Sort the array.
     */
    qsort(data, n, sizeof(dns_rdata_t), rdata_compare_wrapper);
    *rdata = data;
    *nrdata = n;
    dns_rdataset_disassociate(&rdataset);
    return (ISC_R_SUCCESS);
}

isc_result_t
dns_dnssec_keyfromrdata(dns_name_t *name, dns_rdata_t *rdata, isc_mem_t *mctx,
            dst_key_t **key)
{
    isc_buffer_t b;
    isc_region_t r;

    INSIST(name != NULL);
    INSIST(rdata != NULL);
    INSIST(mctx != NULL);
    INSIST(key != NULL);
    INSIST(*key == NULL);
    REQUIRE(rdata->type == dns_rdatatype_key ||
        rdata->type == dns_rdatatype_dnskey);

    dns_rdata_toregion(rdata, &r);
    isc_buffer_init(&b, r.base, r.length);
    isc_buffer_add(&b, r.length);
    return (dst_key_fromdns(name, rdata->rdclass, &b, mctx, key));
}

static isc_result_t
digest_sig(dst_context_t *ctx, dns_rdata_t *sigrdata, dns_rdata_rrsig_t *sig) {
    isc_region_t r;
    isc_result_t ret;
    dns_fixedname_t fname;

    dns_rdata_toregion(sigrdata, &r);
    INSIST(r.length >= 19);

    r.length = 18;
    ret = dst_context_adddata(ctx, &r);
    if (ret != ISC_R_SUCCESS)
        return (ret);
    dns_fixedname_init(&fname);
    RUNTIME_CHECK(dns_name_downcase(&sig->signer,
                    dns_fixedname_name(&fname), NULL)
              == ISC_R_SUCCESS);
    dns_name_toregion(dns_fixedname_name(&fname), &r);
    return (dst_context_adddata(ctx, &r));
}

isc_result_t
dns_dnssec_sign(dns_name_t *name, dns_rdataset_t *set, dst_key_t *key,
        isc_stdtime_t *inception, isc_stdtime_t *expire,
        isc_mem_t *mctx, isc_buffer_t *buffer, dns_rdata_t *sigrdata)
{
    dns_rdata_rrsig_t sig;
    dns_rdata_t tmpsigrdata;
    dns_rdata_t *rdatas;
    int nrdatas, i;
    isc_buffer_t sigbuf, envbuf;
    isc_region_t r;
    dst_context_t *ctx = NULL;
    isc_result_t ret;
    isc_buffer_t *databuf = NULL;
    char data[256 + 8];
    isc_uint32_t flags;
    unsigned int sigsize;
    dns_fixedname_t fnewname;

    REQUIRE(name != NULL);
    REQUIRE(dns_name_countlabels(name) <= 255);
    REQUIRE(set != NULL);
    REQUIRE(key != NULL);
    REQUIRE(inception != NULL);
    REQUIRE(expire != NULL);
    REQUIRE(mctx != NULL);
    REQUIRE(sigrdata != NULL);

    if (*inception >= *expire)
        return (DNS_R_INVALIDTIME);

    /*
     * Is the key allowed to sign data?
     */
    flags = dst_key_flags(key);
    if (flags & DNS_KEYTYPE_NOAUTH)
        return (DNS_R_KEYUNAUTHORIZED);
    if ((flags & DNS_KEYFLAG_OWNERMASK) != DNS_KEYOWNER_ZONE)
        return (DNS_R_KEYUNAUTHORIZED);

    sig.mctx = mctx;
    sig.common.rdclass = set->rdclass;
    sig.common.rdtype = dns_rdatatype_rrsig;
    ISC_LINK_INIT(&sig.common, link);

    dns_name_init(&sig.signer, NULL);
    dns_name_clone(dst_key_name(key), &sig.signer);

    sig.covered = set->type;
    sig.algorithm = dst_key_alg(key);
    sig.labels = dns_name_countlabels(name) - 1;
    if (dns_name_iswildcard(name))
        sig.labels--;
    sig.originalttl = set->ttl;
    sig.timesigned = *inception;
    sig.timeexpire = *expire;
    sig.keyid = dst_key_id(key);
    ret = dst_key_sigsize(key, &sigsize);
    if (ret != ISC_R_SUCCESS)
        return (ret);
    sig.siglen = sigsize;
    /*
     * The actual contents of sig.signature are not important yet, since
     * they're not used in digest_sig().
     */
    sig.signature = isc_mem_get(mctx, sig.siglen);
    if (sig.signature == NULL)
        return (ISC_R_NOMEMORY);

    ret = isc_buffer_allocate(mctx, &databuf, sigsize + 256 + 18);
    if (ret != ISC_R_SUCCESS)
        goto cleanup_signature;

    dns_rdata_init(&tmpsigrdata);
    ret = dns_rdata_fromstruct(&tmpsigrdata, sig.common.rdclass,
                   sig.common.rdtype, &sig, databuf);
    if (ret != ISC_R_SUCCESS)
        goto cleanup_databuf;

    ret = dst_context_create(key, mctx, &ctx);
    if (ret != ISC_R_SUCCESS)
        goto cleanup_databuf;

    /*
     * Digest the SIG rdata.
     */
    ret = digest_sig(ctx, &tmpsigrdata, &sig);
    if (ret != ISC_R_SUCCESS)
        goto cleanup_context;

    dns_fixedname_init(&fnewname);
    RUNTIME_CHECK(dns_name_downcase(name, dns_fixedname_name(&fnewname),
                    NULL) == ISC_R_SUCCESS);
    dns_name_toregion(dns_fixedname_name(&fnewname), &r);

    /*
     * Create an envelope for each rdata: <name|type|class|ttl>.
     */
    isc_buffer_init(&envbuf, data, sizeof(data));
    memcpy(data, r.base, r.length);
    isc_buffer_add(&envbuf, r.length);
    isc_buffer_putuint16(&envbuf, set->type);
    isc_buffer_putuint16(&envbuf, set->rdclass);
    isc_buffer_putuint32(&envbuf, set->ttl);

    ret = rdataset_to_sortedarray(set, mctx, &rdatas, &nrdatas);
    if (ret != ISC_R_SUCCESS)
        goto cleanup_context;
    isc_buffer_usedregion(&envbuf, &r);

    for (i = 0; i < nrdatas; i++) {
        isc_uint16_t len;
        isc_buffer_t lenbuf;
        isc_region_t lenr;

        /*
         * Skip duplicates.
         */
        if (i > 0 && dns_rdata_compare(&rdatas[i], &rdatas[i-1]) == 0)
            continue;

        /*
         * Digest the envelope.
         */
        ret = dst_context_adddata(ctx, &r);
        if (ret != ISC_R_SUCCESS)
            goto cleanup_array;

        /*
         * Digest the length of the rdata.
         */
        isc_buffer_init(&lenbuf, &len, sizeof(len));
        INSIST(rdatas[i].length < 65536);
        isc_buffer_putuint16(&lenbuf, (isc_uint16_t)rdatas[i].length);
        isc_buffer_usedregion(&lenbuf, &lenr);
        ret = dst_context_adddata(ctx, &lenr);
        if (ret != ISC_R_SUCCESS)
            goto cleanup_array;

        /*
         * Digest the rdata.
         */
        ret = dns_rdata_digest(&rdatas[i], digest_callback, ctx);
        if (ret != ISC_R_SUCCESS)
            goto cleanup_array;
    }

    isc_buffer_init(&sigbuf, sig.signature, sig.siglen);
    ret = dst_context_sign(ctx, &sigbuf);
    if (ret != ISC_R_SUCCESS)
        goto cleanup_array;
    isc_buffer_usedregion(&sigbuf, &r);
    if (r.length != sig.siglen) {
        ret = ISC_R_NOSPACE;
        goto cleanup_array;
    }
    memcpy(sig.signature, r.base, sig.siglen);

    ret = dns_rdata_fromstruct(sigrdata, sig.common.rdclass,
                  sig.common.rdtype, &sig, buffer);

cleanup_array:
    isc_mem_put(mctx, rdatas, nrdatas * sizeof(dns_rdata_t));
cleanup_context:
    dst_context_destroy(&ctx);
cleanup_databuf:
    isc_buffer_free(&databuf);
cleanup_signature:
    isc_mem_put(mctx, sig.signature, sig.siglen);

    return (ret);
}

isc_result_t
dns_dnssec_verify2(dns_name_t *name, dns_rdataset_t *set, dst_key_t *key,
           isc_boolean_t ignoretime, isc_mem_t *mctx,
           dns_rdata_t *sigrdata, dns_name_t *wild)
{
    dns_rdata_rrsig_t sig;
    dns_fixedname_t fnewname;
    isc_region_t r;
    isc_buffer_t envbuf;
    dns_rdata_t *rdatas;
    int nrdatas, i;
    isc_stdtime_t now;
    isc_result_t ret;
    unsigned char data[300];
    dst_context_t *ctx = NULL;
    int labels = 0;
    isc_uint32_t flags;

    REQUIRE(name != NULL);
    REQUIRE(set != NULL);
    REQUIRE(key != NULL);
    REQUIRE(mctx != NULL);
    REQUIRE(sigrdata != NULL && sigrdata->type == dns_rdatatype_rrsig);

    ret = dns_rdata_tostruct(sigrdata, &sig, NULL);
    if (ret != ISC_R_SUCCESS)
        return (ret);

    if (set->type != sig.covered)
        return (DNS_R_SIGINVALID);

    if (isc_serial_lt(sig.timeexpire, sig.timesigned))
        return (DNS_R_SIGINVALID);

    if (!ignoretime) {
        isc_stdtime_get(&now);

        /*
         * Is SIG temporally valid?
         */
        if (isc_serial_lt((isc_uint32_t)now, sig.timesigned))
            return (DNS_R_SIGFUTURE);
        else if (isc_serial_lt(sig.timeexpire, (isc_uint32_t)now))
            return (DNS_R_SIGEXPIRED);
    }

    /*
     * NS, SOA and DNSSKEY records are signed by their owner.
     * DS records are signed by the parent.
     */
    switch (set->type) {
    case dns_rdatatype_ns:
    case dns_rdatatype_soa:
    case dns_rdatatype_dnskey:
        if (!dns_name_equal(name, &sig.signer))
            return (DNS_R_SIGINVALID);
        break;
    case dns_rdatatype_ds:
        if (dns_name_equal(name, &sig.signer))
            return (DNS_R_SIGINVALID);
        /* FALLTHROUGH */
    default:
        if (!dns_name_issubdomain(name, &sig.signer))
            return (DNS_R_SIGINVALID);
        break;
    }

    /*
     * Is the key allowed to sign data?
     */
    flags = dst_key_flags(key);
    if (flags & DNS_KEYTYPE_NOAUTH)
        return (DNS_R_KEYUNAUTHORIZED);
    if ((flags & DNS_KEYFLAG_OWNERMASK) != DNS_KEYOWNER_ZONE)
        return (DNS_R_KEYUNAUTHORIZED);

    ret = dst_context_create(key, mctx, &ctx);
    if (ret != ISC_R_SUCCESS)
        goto cleanup_struct;

    /*
     * Digest the SIG rdata (not including the signature).
     */
    ret = digest_sig(ctx, sigrdata, &sig);
    if (ret != ISC_R_SUCCESS)
        goto cleanup_context;

    /*
     * If the name is an expanded wildcard, use the wildcard name.
     */
    dns_fixedname_init(&fnewname);
    labels = dns_name_countlabels(name) - 1;
    RUNTIME_CHECK(dns_name_downcase(name, dns_fixedname_name(&fnewname),
                    NULL) == ISC_R_SUCCESS);
    if (labels - sig.labels > 0)
        dns_name_split(dns_fixedname_name(&fnewname), sig.labels + 1,
                   NULL, dns_fixedname_name(&fnewname));

    dns_name_toregion(dns_fixedname_name(&fnewname), &r);

    /*
     * Create an envelope for each rdata: <name|type|class|ttl>.
     */
    isc_buffer_init(&envbuf, data, sizeof(data));
    if (labels - sig.labels > 0) {
        isc_buffer_putuint8(&envbuf, 1);
        isc_buffer_putuint8(&envbuf, '*');
        memcpy(data + 2, r.base, r.length);
    }
    else
        memcpy(data, r.base, r.length);
    isc_buffer_add(&envbuf, r.length);
    isc_buffer_putuint16(&envbuf, set->type);
    isc_buffer_putuint16(&envbuf, set->rdclass);
    isc_buffer_putuint32(&envbuf, sig.originalttl);

    ret = rdataset_to_sortedarray(set, mctx, &rdatas, &nrdatas);
    if (ret != ISC_R_SUCCESS)
        goto cleanup_context;

    isc_buffer_usedregion(&envbuf, &r);

    for (i = 0; i < nrdatas; i++) {
        isc_uint16_t len;
        isc_buffer_t lenbuf;
        isc_region_t lenr;

        /*
         * Skip duplicates.
         */
        if (i > 0 && dns_rdata_compare(&rdatas[i], &rdatas[i-1]) == 0)
            continue;

        /*
         * Digest the envelope.
         */
        ret = dst_context_adddata(ctx, &r);
        if (ret != ISC_R_SUCCESS)
            goto cleanup_array;

        /*
         * Digest the rdata length.
         */
        isc_buffer_init(&lenbuf, &len, sizeof(len));
        INSIST(rdatas[i].length < 65536);
        isc_buffer_putuint16(&lenbuf, (isc_uint16_t)rdatas[i].length);
        isc_buffer_usedregion(&lenbuf, &lenr);

        /*
         * Digest the rdata.
         */
        ret = dst_context_adddata(ctx, &lenr);
        if (ret != ISC_R_SUCCESS)
            goto cleanup_array;
        ret = dns_rdata_digest(&rdatas[i], digest_callback, ctx);
        if (ret != ISC_R_SUCCESS)
            goto cleanup_array;
    }

    r.base = sig.signature;
    r.length = sig.siglen;
    ret = dst_context_verify(ctx, &r);
    if (ret == DST_R_VERIFYFAILURE)
        ret = DNS_R_SIGINVALID;

cleanup_array:
    isc_mem_put(mctx, rdatas, nrdatas * sizeof(dns_rdata_t));
cleanup_context:
    dst_context_destroy(&ctx);
cleanup_struct:
    dns_rdata_freestruct(&sig);

    if (ret == ISC_R_SUCCESS && labels - sig.labels > 0) {
        if (wild != NULL)
            RUNTIME_CHECK(dns_name_concatenate(dns_wildcardname,
                         dns_fixedname_name(&fnewname),
                         wild, NULL) == ISC_R_SUCCESS);
        ret = DNS_R_FROMWILDCARD;
    }
    return (ret);
}

isc_result_t
dns_dnssec_verify(dns_name_t *name, dns_rdataset_t *set, dst_key_t *key,
          isc_boolean_t ignoretime, isc_mem_t *mctx,
          dns_rdata_t *sigrdata)
{
    isc_result_t result;

    result = dns_dnssec_verify2(name, set, key, ignoretime, mctx,
                    sigrdata, NULL);
    if (result == DNS_R_FROMWILDCARD)
        result = ISC_R_SUCCESS;
    return (result);
}

#define is_zone_key(key) ((dst_key_flags(key) & DNS_KEYFLAG_OWNERMASK) \
              == DNS_KEYOWNER_ZONE)

isc_result_t
dns_dnssec_findzonekeys2(dns_db_t *db, dns_dbversion_t *ver,
             dns_dbnode_t *node, dns_name_t *name,
             const char *directory, isc_mem_t *mctx,
             unsigned int maxkeys, dst_key_t **keys,
             unsigned int *nkeys)
{
    dns_rdataset_t rdataset;
    dns_rdata_t rdata = DNS_RDATA_INIT;
    isc_result_t result;
    dst_key_t *pubkey = NULL;
    unsigned int count = 0;

    REQUIRE(nkeys != NULL);
    REQUIRE(keys != NULL);

    *nkeys = 0;
    dns_rdataset_init(&rdataset);
    RETERR(dns_db_findrdataset(db, node, ver, dns_rdatatype_dnskey, 0, 0,
                   &rdataset, NULL));
    RETERR(dns_rdataset_first(&rdataset));
    while (result == ISC_R_SUCCESS && count < maxkeys) {
        pubkey = NULL;
        dns_rdataset_current(&rdataset, &rdata);
        RETERR(dns_dnssec_keyfromrdata(name, &rdata, mctx, &pubkey));
        if (!is_zone_key(pubkey) ||
            (dst_key_flags(pubkey) & DNS_KEYTYPE_NOAUTH) != 0)
            goto next;
        /* Corrupted .key file? */
        if (!dns_name_equal(name, dst_key_name(pubkey)))
            goto next;
        keys[count] = NULL;
        result = dst_key_fromfile(dst_key_name(pubkey),
                      dst_key_id(pubkey),
                      dst_key_alg(pubkey),
                      DST_TYPE_PUBLIC|DST_TYPE_PRIVATE,
                      directory,
                      mctx, &keys[count]);
        if (result == ISC_R_FILENOTFOUND) {
            keys[count] = pubkey;
            pubkey = NULL;
            count++;
            goto next;
        }
        if (result != ISC_R_SUCCESS)
            goto failure;
        if ((dst_key_flags(keys[count]) & DNS_KEYTYPE_NOAUTH) != 0) {
            /* We should never get here. */
            dst_key_free(&keys[count]);
            goto next;
        }
        count++;
 next:
        if (pubkey != NULL)
            dst_key_free(&pubkey);
        dns_rdata_reset(&rdata);
        result = dns_rdataset_next(&rdataset);
    }
    if (result != ISC_R_NOMORE)
        goto failure;
    if (count == 0)
        result = ISC_R_NOTFOUND;
    else
        result = ISC_R_SUCCESS;

 failure:
    if (dns_rdataset_isassociated(&rdataset))
        dns_rdataset_disassociate(&rdataset);
    if (pubkey != NULL)
        dst_key_free(&pubkey);
    if (result != ISC_R_SUCCESS)
        while (count > 0)
            dst_key_free(&keys[--count]);
    *nkeys = count;
    return (result);
}

isc_result_t
dns_dnssec_findzonekeys(dns_db_t *db, dns_dbversion_t *ver,
            dns_dbnode_t *node, dns_name_t *name, isc_mem_t *mctx,
            unsigned int maxkeys, dst_key_t **keys,
            unsigned int *nkeys)
{
    return (dns_dnssec_findzonekeys2(db, ver, node, name, NULL, mctx,
                     maxkeys, keys, nkeys));
}

isc_result_t
dns_dnssec_signmessage(dns_message_t *msg, dst_key_t *key) {
    dns_rdata_sig_t sig;    /* SIG(0) */
    unsigned char data[512];
    unsigned char header[DNS_MESSAGE_HEADERLEN];
    isc_buffer_t headerbuf, databuf, sigbuf;
    unsigned int sigsize;
    isc_buffer_t *dynbuf = NULL;
    dns_rdata_t *rdata;
    dns_rdatalist_t *datalist;
    dns_rdataset_t *dataset;
    isc_region_t r;
    isc_stdtime_t now;
    dst_context_t *ctx = NULL;
    isc_mem_t *mctx;
    isc_result_t result;
    isc_boolean_t signeedsfree = ISC_TRUE;

    REQUIRE(msg != NULL);
    REQUIRE(key != NULL);

    if (is_response(msg))
        REQUIRE(msg->query.base != NULL);

    mctx = msg->mctx;

    memset(&sig, 0, sizeof(sig));

    sig.mctx = mctx;
    sig.common.rdclass = dns_rdataclass_any;
    sig.common.rdtype = dns_rdatatype_sig;  /* SIG(0) */
    ISC_LINK_INIT(&sig.common, link);

    sig.covered = 0;
    sig.algorithm = dst_key_alg(key);
    sig.labels = 0; /* the root name */
    sig.originalttl = 0;

    isc_stdtime_get(&now);
    sig.timesigned = now - DNS_TSIG_FUDGE;
    sig.timeexpire = now + DNS_TSIG_FUDGE;

    sig.keyid = dst_key_id(key);

    dns_name_init(&sig.signer, NULL);
    dns_name_clone(dst_key_name(key), &sig.signer);

    sig.siglen = 0;
    sig.signature = NULL;

    isc_buffer_init(&databuf, data, sizeof(data));

    RETERR(dst_context_create(key, mctx, &ctx));

    /*
     * Digest the fields of the SIG - we can cheat and use
     * dns_rdata_fromstruct.  Since siglen is 0, the digested data
     * is identical to dns format.
     */
    RETERR(dns_rdata_fromstruct(NULL, dns_rdataclass_any,
                    dns_rdatatype_sig /* SIG(0) */,
                    &sig, &databuf));
    isc_buffer_usedregion(&databuf, &r);
    RETERR(dst_context_adddata(ctx, &r));

    /*
     * If this is a response, digest the query.
     */
    if (is_response(msg))
        RETERR(dst_context_adddata(ctx, &msg->query));

    /*
     * Digest the header.
     */
    isc_buffer_init(&headerbuf, header, sizeof(header));
    dns_message_renderheader(msg, &headerbuf);
    isc_buffer_usedregion(&headerbuf, &r);
    RETERR(dst_context_adddata(ctx, &r));

    /*
     * Digest the remainder of the message.
     */
    isc_buffer_usedregion(msg->buffer, &r);
    isc_region_consume(&r, DNS_MESSAGE_HEADERLEN);
    RETERR(dst_context_adddata(ctx, &r));

    RETERR(dst_key_sigsize(key, &sigsize));
    sig.siglen = sigsize;
    sig.signature = (unsigned char *) isc_mem_get(mctx, sig.siglen);
    if (sig.signature == NULL) {
        result = ISC_R_NOMEMORY;
        goto failure;
    }

    isc_buffer_init(&sigbuf, sig.signature, sig.siglen);
    RETERR(dst_context_sign(ctx, &sigbuf));
    dst_context_destroy(&ctx);

    rdata = NULL;
    RETERR(dns_message_gettemprdata(msg, &rdata));
    RETERR(isc_buffer_allocate(msg->mctx, &dynbuf, 1024));
    RETERR(dns_rdata_fromstruct(rdata, dns_rdataclass_any,
                    dns_rdatatype_sig /* SIG(0) */,
                    &sig, dynbuf));

    isc_mem_put(mctx, sig.signature, sig.siglen);
    signeedsfree = ISC_FALSE;

    dns_message_takebuffer(msg, &dynbuf);

    datalist = NULL;
    RETERR(dns_message_gettemprdatalist(msg, &datalist));
    datalist->rdclass = dns_rdataclass_any;
    datalist->type = dns_rdatatype_sig; /* SIG(0) */
    datalist->covers = 0;
    datalist->ttl = 0;
    ISC_LIST_INIT(datalist->rdata);
    ISC_LIST_APPEND(datalist->rdata, rdata, link);
    dataset = NULL;
    RETERR(dns_message_gettemprdataset(msg, &dataset));
    dns_rdataset_init(dataset);
    RUNTIME_CHECK(dns_rdatalist_tordataset(datalist, dataset) == ISC_R_SUCCESS);
    msg->sig0 = dataset;

    return (ISC_R_SUCCESS);

failure:
    if (dynbuf != NULL)
        isc_buffer_free(&dynbuf);
    if (signeedsfree)
        isc_mem_put(mctx, sig.signature, sig.siglen);
    if (ctx != NULL)
        dst_context_destroy(&ctx);

    return (result);
}

isc_result_t
dns_dnssec_verifymessage(isc_buffer_t *source, dns_message_t *msg,
             dst_key_t *key)
{
    dns_rdata_sig_t sig;    /* SIG(0) */
    unsigned char header[DNS_MESSAGE_HEADERLEN];
    dns_rdata_t rdata = DNS_RDATA_INIT;
    isc_region_t r, source_r, sig_r, header_r;
    isc_stdtime_t now;
    dst_context_t *ctx = NULL;
    isc_mem_t *mctx;
    isc_result_t result;
    isc_uint16_t addcount;
    isc_boolean_t signeedsfree = ISC_FALSE;

    REQUIRE(source != NULL);
    REQUIRE(msg != NULL);
    REQUIRE(key != NULL);

    mctx = msg->mctx;

    msg->verify_attempted = 1;

    if (is_response(msg)) {
        if (msg->query.base == NULL)
            return (DNS_R_UNEXPECTEDTSIG);
    }

    isc_buffer_usedregion(source, &source_r);

    RETERR(dns_rdataset_first(msg->sig0));
    dns_rdataset_current(msg->sig0, &rdata);

    RETERR(dns_rdata_tostruct(&rdata, &sig, NULL));
    signeedsfree = ISC_TRUE;

    if (sig.labels != 0) {
        result = DNS_R_SIGINVALID;
        goto failure;
    }

    if (isc_serial_lt(sig.timeexpire, sig.timesigned)) {
        result = DNS_R_SIGINVALID;
        msg->sig0status = dns_tsigerror_badtime;
        goto failure;
    }

    isc_stdtime_get(&now);
    if (isc_serial_lt((isc_uint32_t)now, sig.timesigned)) {
        result = DNS_R_SIGFUTURE;
        msg->sig0status = dns_tsigerror_badtime;
        goto failure;
    }
    else if (isc_serial_lt(sig.timeexpire, (isc_uint32_t)now)) {
        result = DNS_R_SIGEXPIRED;
        msg->sig0status = dns_tsigerror_badtime;
        goto failure;
    }

    if (!dns_name_equal(dst_key_name(key), &sig.signer)) {
        result = DNS_R_SIGINVALID;
        msg->sig0status = dns_tsigerror_badkey;
        goto failure;
    }

    RETERR(dst_context_create(key, mctx, &ctx));

    /*
     * Digest the SIG(0) record, except for the signature.
     */
    dns_rdata_toregion(&rdata, &r);
    r.length -= sig.siglen;
    RETERR(dst_context_adddata(ctx, &r));

    /*
     * If this is a response, digest the query.
     */
    if (is_response(msg))
        RETERR(dst_context_adddata(ctx, &msg->query));

    /*
     * Extract the header.
     */
    memcpy(header, source_r.base, DNS_MESSAGE_HEADERLEN);

    /*
     * Decrement the additional field counter.
     */
    memcpy(&addcount, &header[DNS_MESSAGE_HEADERLEN - 2], 2);
    addcount = htons((isc_uint16_t)(ntohs(addcount) - 1));
    memcpy(&header[DNS_MESSAGE_HEADERLEN - 2], &addcount, 2);

    /*
     * Digest the modified header.
     */
    header_r.base = (unsigned char *) header;
    header_r.length = DNS_MESSAGE_HEADERLEN;
    RETERR(dst_context_adddata(ctx, &header_r));

    /*
     * Digest all non-SIG(0) records.
     */
    r.base = source_r.base + DNS_MESSAGE_HEADERLEN;
    r.length = msg->sigstart - DNS_MESSAGE_HEADERLEN;
    RETERR(dst_context_adddata(ctx, &r));

    sig_r.base = sig.signature;
    sig_r.length = sig.siglen;
    result = dst_context_verify(ctx, &sig_r);
    if (result != ISC_R_SUCCESS) {
        msg->sig0status = dns_tsigerror_badsig;
        goto failure;
    }

    msg->verified_sig = 1;

    dst_context_destroy(&ctx);
    dns_rdata_freestruct(&sig);

    return (ISC_R_SUCCESS);

failure:
    if (signeedsfree)
        dns_rdata_freestruct(&sig);
    if (ctx != NULL)
        dst_context_destroy(&ctx);

    return (result);
}

/*%
 * Does this key ('rdata') self sign the rrset ('rdataset')?
 */
isc_boolean_t
dns_dnssec_selfsigns(dns_rdata_t *rdata, dns_name_t *name,
             dns_rdataset_t *rdataset, dns_rdataset_t *sigrdataset,
             isc_boolean_t ignoretime, isc_mem_t *mctx)
{
    dst_key_t *dstkey = NULL;
    dns_keytag_t keytag;
    dns_rdata_dnskey_t key;
    dns_rdata_rrsig_t sig;
    dns_rdata_t sigrdata = DNS_RDATA_INIT;
    isc_result_t result;

    INSIST(rdataset->type == dns_rdatatype_key ||
           rdataset->type == dns_rdatatype_dnskey);
    if (rdataset->type == dns_rdatatype_key) {
        INSIST(sigrdataset->type == dns_rdatatype_sig);
        INSIST(sigrdataset->covers == dns_rdatatype_key);
    } else {
        INSIST(sigrdataset->type == dns_rdatatype_rrsig);
        INSIST(sigrdataset->covers == dns_rdatatype_dnskey);
    }

    result = dns_dnssec_keyfromrdata(name, rdata, mctx, &dstkey);
    if (result != ISC_R_SUCCESS)
        return (ISC_FALSE);
    result = dns_rdata_tostruct(rdata, &key, NULL);
    RUNTIME_CHECK(result == ISC_R_SUCCESS);

    keytag = dst_key_id(dstkey);
    for (result = dns_rdataset_first(sigrdataset);
         result == ISC_R_SUCCESS;
         result = dns_rdataset_next(sigrdataset))
    {
        dns_rdata_reset(&sigrdata);
        dns_rdataset_current(sigrdataset, &sigrdata);
        result = dns_rdata_tostruct(&sigrdata, &sig, NULL);
        RUNTIME_CHECK(result == ISC_R_SUCCESS);

        if (sig.algorithm == key.algorithm &&
            sig.keyid == keytag) {
            result = dns_dnssec_verify2(name, rdataset, dstkey,
                            ignoretime, mctx,
                            &sigrdata, NULL);
            if (result == ISC_R_SUCCESS) {
                dst_key_free(&dstkey);
                return (ISC_TRUE);
            }
        }
    }
    dst_key_free(&dstkey);
    return (ISC_FALSE);
}

isc_result_t
dns_dnsseckey_create(isc_mem_t *mctx, dst_key_t **dstkey,
             dns_dnsseckey_t **dkp)
{
    isc_result_t result;
    dns_dnsseckey_t *dk;
    int major, minor;

    REQUIRE(dkp != NULL && *dkp == NULL);
    dk = isc_mem_get(mctx, sizeof(dns_dnsseckey_t));
    if (dk == NULL)
        return (ISC_R_NOMEMORY);

    dk->key = *dstkey;
    *dstkey = NULL;
    dk->force_publish = ISC_FALSE;
    dk->force_sign = ISC_FALSE;
    dk->hint_publish = ISC_FALSE;
    dk->hint_sign = ISC_FALSE;
    dk->hint_remove = ISC_FALSE;
    dk->first_sign = ISC_FALSE;
    dk->is_active = ISC_FALSE;
    dk->prepublish = 0;
    dk->source = dns_keysource_unknown;
    dk->index = 0;

    /* KSK or ZSK? */
    dk->ksk = ISC_TF((dst_key_flags(dk->key) & DNS_KEYFLAG_KSK) != 0);

    /* Is this an old-style key? */
    result = dst_key_getprivateformat(dk->key, &major, &minor);

    /* Smart signing started with key format 1.3 */
    dk->legacy = ISC_TF(major == 1 && minor <= 2);

    ISC_LINK_INIT(dk, link);
    *dkp = dk;
    return (ISC_R_SUCCESS);
}

void
dns_dnsseckey_destroy(isc_mem_t *mctx, dns_dnsseckey_t **dkp) {
    dns_dnsseckey_t *dk;

    REQUIRE(dkp != NULL && *dkp != NULL);
    dk = *dkp;
    if (dk->key != NULL)
        dst_key_free(&dk->key);
    isc_mem_put(mctx, dk, sizeof(dns_dnsseckey_t));
    *dkp = NULL;
}

static void
get_hints(dns_dnsseckey_t *key) {
    isc_result_t result;
    isc_stdtime_t now, publish, active, revoke, inactive, delete;
    isc_boolean_t pubset = ISC_FALSE, actset = ISC_FALSE;
    isc_boolean_t revset = ISC_FALSE, inactset = ISC_FALSE;
    isc_boolean_t delset = ISC_FALSE;

    REQUIRE(key != NULL && key->key != NULL);

    isc_stdtime_get(&now);

    result = dst_key_gettime(key->key, DST_TIME_PUBLISH, &publish);
    if (result == ISC_R_SUCCESS)
        pubset = ISC_TRUE;

    result = dst_key_gettime(key->key, DST_TIME_ACTIVATE, &active);
    if (result == ISC_R_SUCCESS)
        actset = ISC_TRUE;

    result = dst_key_gettime(key->key, DST_TIME_REVOKE, &revoke);
    if (result == ISC_R_SUCCESS)
        revset = ISC_TRUE;

    result = dst_key_gettime(key->key, DST_TIME_INACTIVE, &inactive);
    if (result == ISC_R_SUCCESS)
        inactset = ISC_TRUE;

    result = dst_key_gettime(key->key, DST_TIME_DELETE, &delete);
    if (result == ISC_R_SUCCESS)
        delset = ISC_TRUE;

    /* Metadata says publish (but possibly not activate) */
    if (pubset && publish <= now)
        key->hint_publish = ISC_TRUE;

    /* Metadata says activate (so we must also publish) */
    if (actset && active <= now) {
        key->hint_sign = ISC_TRUE;
        key->hint_publish = ISC_TRUE;
    }

    /*
     * Activation date is set (maybe in the future), but
     * publication date isn't. Most likely the user wants to
     * publish now and activate later.
     */
    if (actset && !pubset)
        key->hint_publish = ISC_TRUE;

    /*
     * If activation date is in the future, make note of how far off
     */
    if (key->hint_publish && actset && active > now) {
        key->prepublish = active - now;
    }

    /*
     * Key has been marked inactive: we can continue publishing,
     * but don't sign.
     */
    if (key->hint_publish && inactset && inactive <= now) {
        key->hint_sign = ISC_FALSE;
    }

    /*
     * Metadata says revoke.  If the key is published,
     * we *have to* sign with it per RFC5011--even if it was
     * not active before.
     *
     * If it hasn't already been done, we should also revoke it now.
     */
    if (key->hint_publish && (revset && revoke < now)) {
        isc_uint32_t flags;
        key->hint_sign = ISC_TRUE;
        flags = dst_key_flags(key->key);
        if ((flags & DNS_KEYFLAG_REVOKE) == 0) {
            flags |= DNS_KEYFLAG_REVOKE;
            dst_key_setflags(key->key, flags);
        }
    }

    /*
     * Metadata says delete, so don't publish this key or sign with it.
     */
    if (delset && delete <= now) {
        key->hint_publish = ISC_FALSE;
        key->hint_sign = ISC_FALSE;
        key->hint_remove = ISC_TRUE;
    }
}

/*%
 * Get a list of DNSSEC keys from the key repository
 */
isc_result_t
dns_dnssec_findmatchingkeys(dns_name_t *origin, const char *directory,
                isc_mem_t *mctx, dns_dnsseckeylist_t *keylist)
{
    isc_result_t result = ISC_R_SUCCESS;
    isc_boolean_t dir_open = ISC_FALSE;
    dns_dnsseckeylist_t list;
    isc_dir_t dir;
    dns_dnsseckey_t *key = NULL;
    dst_key_t *dstkey = NULL;
    char namebuf[DNS_NAME_FORMATSIZE], *p;
    isc_buffer_t b;
    unsigned int len;

    REQUIRE(keylist != NULL);
    ISC_LIST_INIT(list);
    isc_dir_init(&dir);

    isc_buffer_init(&b, namebuf, sizeof(namebuf) - 1);
    RETERR(dns_name_totext(origin, ISC_FALSE, &b));
    len = isc_buffer_usedlength(&b);
    namebuf[len] = '\0';

    RETERR(isc_dir_open(&dir, directory));
    dir_open = ISC_TRUE;

    while (isc_dir_read(&dir) == ISC_R_SUCCESS) {
        if (dir.entry.name[0] == 'K' &&
            dir.entry.length > len + 1 &&
            dir.entry.name[len + 1] == '+' &&
            strncasecmp(dir.entry.name + 1, namebuf, len) == 0) {
            p = strrchr(dir.entry.name, '.');
            if (p != NULL && strcmp(p, ".private") != 0)
                continue;

            dstkey = NULL;
            RETERR(dst_key_fromnamedfile(dir.entry.name, directory,
                         DST_TYPE_PUBLIC | DST_TYPE_PRIVATE,
                         mctx, &dstkey));

            RETERR(dns_dnsseckey_create(mctx, &dstkey, &key));
            key->source = dns_keysource_repository;
            get_hints(key);

            if (key->legacy) {
                dns_dnsseckey_destroy(mctx, &key);
            } else {
                ISC_LIST_APPEND(list, key, link);
                key = NULL;
            }
        }
    }

    if (!ISC_LIST_EMPTY(list))
        ISC_LIST_APPENDLIST(*keylist, list, link);
    else
        result = ISC_R_NOTFOUND;

 failure:
    if (dir_open)
        isc_dir_close(&dir);
    INSIST(key == NULL);
    while ((key = ISC_LIST_HEAD(list)) != NULL) {
        ISC_LIST_UNLINK(list, key, link);
        INSIST(key->key != NULL);
        dst_key_free(&key->key);
        dns_dnsseckey_destroy(mctx, &key);
    }
    if (dstkey != NULL)
        dst_key_free(&dstkey);
    return (result);
}

/*%
 * Add 'newkey' to 'keylist' if it's not already there.
 *
 * If 'savekeys' is ISC_TRUE, then we need to preserve all
 * the keys in the keyset, regardless of whether they have
 * metadata indicating they should be deactivated or removed.
 */
static void
addkey(dns_dnsseckeylist_t *keylist, dst_key_t **newkey,
       isc_boolean_t savekeys, isc_mem_t *mctx)
{
    dns_dnsseckey_t *key;

    /* Skip duplicates */
    for (key = ISC_LIST_HEAD(*keylist);
         key != NULL;
         key = ISC_LIST_NEXT(key, link)) {
        if (dst_key_id(key->key) == dst_key_id(*newkey) &&
            dst_key_alg(key->key) == dst_key_alg(*newkey) &&
            dns_name_equal(dst_key_name(key->key),
                   dst_key_name(*newkey)))
            break;
    }

    if (key != NULL) {
        /*
         * Found a match.  If the old key was only public and the
         * new key is private, replace the old one; otherwise
         * leave it.  But either way, mark the key as having
         * been found in the zone.
         */
        if (dst_key_isprivate(key->key)) {
            dst_key_free(newkey);
        } else if (dst_key_isprivate(*newkey)) {
            dst_key_free(&key->key);
            key->key = *newkey;
        }

        key->source = dns_keysource_zoneapex;
        return;
    }

    dns_dnsseckey_create(mctx, newkey, &key);
    if (key->legacy || savekeys) {
        key->force_publish = ISC_TRUE;
        key->force_sign = dst_key_isprivate(key->key);
    }
    key->source = dns_keysource_zoneapex;
    ISC_LIST_APPEND(*keylist, key, link);
    *newkey = NULL;
}


/*%
 * Mark all keys which signed the DNSKEY/SOA RRsets as "active",
 * for future reference.
 */
static isc_result_t
mark_active_keys(dns_dnsseckeylist_t *keylist, dns_rdataset_t *rrsigs) {
    isc_result_t result = ISC_R_SUCCESS;
    dns_rdata_t rdata = DNS_RDATA_INIT;
    dns_rdataset_t sigs;
    dns_dnsseckey_t *key;

    REQUIRE(rrsigs != NULL && dns_rdataset_isassociated(rrsigs));

    dns_rdataset_init(&sigs);
    dns_rdataset_clone(rrsigs, &sigs);
    for (key = ISC_LIST_HEAD(*keylist);
         key != NULL;
         key = ISC_LIST_NEXT(key, link)) {
        isc_uint16_t keyid, sigid;
        dns_secalg_t keyalg, sigalg;
        keyid = dst_key_id(key->key);
        keyalg = dst_key_alg(key->key);

        for (result = dns_rdataset_first(&sigs);
             result == ISC_R_SUCCESS;
             result = dns_rdataset_next(&sigs)) {
            dns_rdata_rrsig_t sig;

            dns_rdata_reset(&rdata);
            dns_rdataset_current(&sigs, &rdata);
            result = dns_rdata_tostruct(&rdata, &sig, NULL);
            RUNTIME_CHECK(result == ISC_R_SUCCESS);
            sigalg = sig.algorithm;
            sigid = sig.keyid;
            if (keyid == sigid && keyalg == sigalg) {
                key->is_active = ISC_TRUE;
                break;
            }
        }
    }

    if (result == ISC_R_NOMORE)
        result = ISC_R_SUCCESS;

    if (dns_rdataset_isassociated(&sigs))
        dns_rdataset_disassociate(&sigs);
    return (result);
}

/*%
 * Add the contents of a DNSKEY rdataset 'keyset' to 'keylist'.
 */
isc_result_t
dns_dnssec_keylistfromrdataset(dns_name_t *origin,
                   const char *directory, isc_mem_t *mctx,
                   dns_rdataset_t *keyset, dns_rdataset_t *keysigs,
                   dns_rdataset_t *soasigs, isc_boolean_t savekeys,
                   isc_boolean_t public,
                   dns_dnsseckeylist_t *keylist)
{
    dns_rdataset_t keys;
    dns_rdata_t rdata = DNS_RDATA_INIT;
    dst_key_t *pubkey = NULL, *privkey = NULL;
    isc_result_t result;

    REQUIRE(keyset != NULL && dns_rdataset_isassociated(keyset));

    dns_rdataset_init(&keys);

    dns_rdataset_clone(keyset, &keys);
    for (result = dns_rdataset_first(&keys);
         result == ISC_R_SUCCESS;
         result = dns_rdataset_next(&keys)) {
        dns_rdata_reset(&rdata);
        dns_rdataset_current(&keys, &rdata);
        RETERR(dns_dnssec_keyfromrdata(origin, &rdata, mctx, &pubkey));

        if (!is_zone_key(pubkey) ||
            (dst_key_flags(pubkey) & DNS_KEYTYPE_NOAUTH) != 0)
            goto skip;

        /* Corrupted .key file? */
        if (!dns_name_equal(origin, dst_key_name(pubkey)))
            goto skip;

        if (public) {
            addkey(keylist, &pubkey, savekeys, mctx);
            goto skip;
        }

        result = dst_key_fromfile(dst_key_name(pubkey),
                      dst_key_id(pubkey),
                      dst_key_alg(pubkey),
                      DST_TYPE_PUBLIC|DST_TYPE_PRIVATE,
                      directory, mctx, &privkey);
        if (result == ISC_R_FILENOTFOUND) {
            addkey(keylist, &pubkey, savekeys, mctx);
            goto skip;
        }
        RETERR(result);

        /* This should never happen. */
        if ((dst_key_flags(privkey) & DNS_KEYTYPE_NOAUTH) != 0)
            goto skip;

        addkey(keylist, &privkey, savekeys, mctx);
 skip:
        if (pubkey != NULL)
            dst_key_free(&pubkey);
        if (privkey != NULL)
            dst_key_free(&privkey);
    }

    if (result != ISC_R_NOMORE)
        RETERR(result);

    if (keysigs != NULL && dns_rdataset_isassociated(keysigs))
        RETERR(mark_active_keys(keylist, keysigs));

    if (soasigs != NULL && dns_rdataset_isassociated(soasigs))
        RETERR(mark_active_keys(keylist, soasigs));

    result = ISC_R_SUCCESS;

 failure:
    if (dns_rdataset_isassociated(&keys))
        dns_rdataset_disassociate(&keys);
    if (pubkey != NULL)
        dst_key_free(&pubkey);
    if (privkey != NULL)
        dst_key_free(&privkey);
    return (result);
}

static isc_result_t
make_dnskey(dst_key_t *key, dns_rdata_t *target) {
    isc_result_t result;
    unsigned char data[DST_KEY_MAXSIZE];
    isc_buffer_t b;
    isc_region_t r;

    isc_buffer_init(&b, data, sizeof(data));
    result = dst_key_todns(key, &b);
    if (result != ISC_R_SUCCESS)
        return (result);

    dns_rdata_reset(target);
    isc_buffer_usedregion(&b, &r);
    dns_rdata_fromregion(target, dst_key_class(key),
                 dns_rdatatype_dnskey, &r);
    return (ISC_R_SUCCESS);
}

static isc_result_t
publish_key(dns_diff_t *add, dns_dnsseckey_t *key, dns_name_t *origin,
        dns_ttl_t ttl, isc_mem_t *mctx, isc_boolean_t allzsk,
        void (*report)(const char *, ...))
{
    isc_result_t result;
    dns_difftuple_t *tuple = NULL;
    dns_rdata_t dnskey = DNS_RDATA_INIT;
    char alg[80];

    dns_rdata_reset(&dnskey);
    RETERR(make_dnskey(key->key, &dnskey));

    dns_secalg_format(dst_key_alg(key->key), alg, sizeof(alg));
    report("Fetching %s %d/%s from key %s\n",
           key->ksk ?  (allzsk ?  "KSK/ZSK" : "KSK") : "ZSK",
           dst_key_id(key->key), alg,
           key->source == dns_keysource_user ?  "file" : "repository");

    if (key->prepublish && ttl > key->prepublish) {
        char keystr[DST_KEY_FORMATSIZE];
        isc_stdtime_t now;

        dst_key_format(key->key, keystr, sizeof(keystr));
        report("Key %s: Delaying activation to match the DNSKEY TTL.",
               keystr, ttl);

        isc_stdtime_get(&now);
        dst_key_settime(key->key, DST_TIME_ACTIVATE, now + ttl);
    }

    /* publish key */
    RETERR(dns_difftuple_create(mctx, DNS_DIFFOP_ADD, origin, ttl,
                    &dnskey, &tuple));
    dns_diff_append(add, &tuple);
    result = ISC_R_SUCCESS;

 failure:
    return (result);
}

static isc_result_t
remove_key(dns_diff_t *del, dns_dnsseckey_t *key, dns_name_t *origin,
      dns_ttl_t ttl, isc_mem_t *mctx, const char *reason,
      void (*report)(const char *, ...))
{
    isc_result_t result;
    dns_difftuple_t *tuple = NULL;
    dns_rdata_t dnskey = DNS_RDATA_INIT;
    char alg[80];

    dns_secalg_format(dst_key_alg(key->key), alg, sizeof(alg));
    report("Removing %s key %d/%s from DNSKEY RRset.\n",
           reason, dst_key_id(key->key), alg);

    RETERR(make_dnskey(key->key, &dnskey));
    RETERR(dns_difftuple_create(mctx, DNS_DIFFOP_DEL, origin, ttl, &dnskey,
                    &tuple));
    dns_diff_append(del, &tuple);
    result = ISC_R_SUCCESS;

 failure:
    return (result);
}

/*
 * Update 'keys' with information from 'newkeys'.
 *
 * If 'removed' is not NULL, any keys that are being removed from
 * the zone will be added to the list for post-removal processing.
 */
isc_result_t
dns_dnssec_updatekeys(dns_dnsseckeylist_t *keys, dns_dnsseckeylist_t *newkeys,
              dns_dnsseckeylist_t *removed, dns_name_t *origin,
              dns_ttl_t ttl, dns_diff_t *add, dns_diff_t *del,
              isc_boolean_t allzsk, isc_mem_t *mctx,
              void (*report)(const char *, ...))
{
    isc_result_t result;
    dns_dnsseckey_t *key, *key1, *key2, *next;

    /*
     * First, look through the existing key list to find keys
     * supplied from the command line which are not in the zone.
     * Update the zone to include them.
     */
    for (key = ISC_LIST_HEAD(*keys);
         key != NULL;
         key = ISC_LIST_NEXT(key, link)) {
        if (key->source == dns_keysource_user &&
            (key->hint_publish || key->force_publish)) {
            RETERR(publish_key(add, key, origin, ttl,
                       mctx, allzsk, report));
        }
    }

    /*
     * Second, scan the list of newly found keys looking for matches
     * with known keys, and update accordingly.
     */
    for (key1 = ISC_LIST_HEAD(*newkeys); key1 != NULL; key1 = next) {
        isc_boolean_t key_revoked = ISC_FALSE;

        next = ISC_LIST_NEXT(key1, link);

        for (key2 = ISC_LIST_HEAD(*keys);
             key2 != NULL;
             key2 = ISC_LIST_NEXT(key2, link)) {
            if (dst_key_pubcompare(key1->key, key2->key,
                           ISC_TRUE)) {
                int r1, r2;
                r1 = dst_key_flags(key1->key) &
                    DNS_KEYFLAG_REVOKE;
                r2 = dst_key_flags(key2->key) &
                    DNS_KEYFLAG_REVOKE;
                key_revoked = ISC_TF(r1 != r2);
                break;
            }
        }

        /* No match found in keys; add the new key. */
        if (key2 == NULL) {
            dns_dnsseckey_t *next;

            next = ISC_LIST_NEXT(key1, link);
            ISC_LIST_UNLINK(*newkeys, key1, link);
            ISC_LIST_APPEND(*keys, key1, link);

            if (key1->source != dns_keysource_zoneapex &&
                (key1->hint_publish || key1->force_publish)) {
                RETERR(publish_key(add, key1, origin, ttl,
                           mctx, allzsk, report));
                if (key1->hint_sign || key1->force_sign)
                    key1->first_sign = ISC_TRUE;
            }

            continue;
        }

        /* Match found: remove or update it as needed */
        if (key1->hint_remove) {
            RETERR(remove_key(del, key2, origin, ttl, mctx,
                      "expired", report));
            ISC_LIST_UNLINK(*keys, key2, link);
            if (removed != NULL)
                ISC_LIST_APPEND(*removed, key2, link);
            else
                dns_dnsseckey_destroy(mctx, &key2);
        } else if (key_revoked &&
             (dst_key_flags(key1->key) & DNS_KEYFLAG_REVOKE) != 0) {

            /*
             * A previously valid key has been revoked.
             * We need to remove the old version and pull
             * in the new one.
             */
            RETERR(remove_key(del, key2, origin, ttl, mctx,
                      "revoked", report));
            ISC_LIST_UNLINK(*keys, key2, link);
            if (removed != NULL)
                ISC_LIST_APPEND(*removed, key2, link);
            else
                dns_dnsseckey_destroy(mctx, &key2);

            RETERR(publish_key(add, key1, origin, ttl,
                       mctx, allzsk, report));
            ISC_LIST_UNLINK(*newkeys, key1, link);
            ISC_LIST_APPEND(*keys, key1, link);

            /*
             * XXX: The revoke flag is only defined for trust
             * anchors.  Setting the flag on a non-KSK is legal,
             * but not defined in any RFC.  It seems reasonable
             * to treat it the same as a KSK: keep it in the
             * zone, sign the DNSKEY set with it, but not
             * sign other records with it.
             */
            key1->ksk = ISC_TRUE;
            continue;
        } else {
            if (!key2->is_active &&
                (key1->hint_sign || key1->force_sign))
                key2->first_sign = ISC_TRUE;
            key2->hint_sign = key1->hint_sign;
            key2->hint_publish = key1->hint_publish;
        }
    }

    /* Free any leftover keys in newkeys */
    while (!ISC_LIST_EMPTY(*newkeys)) {
        key1 = ISC_LIST_HEAD(*newkeys);
        ISC_LIST_UNLINK(*newkeys, key1, link);
        dns_dnsseckey_destroy(mctx, &key1);
    }

    result = ISC_R_SUCCESS;

 failure:
    return (result);
}