Adding upstream version 1:9.16.44.upstream/1%9.16.44upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1604 insertions, 0 deletions

diff --git a/lib/dns/tkey.c b/lib/dns/tkey.c
new file mode 100644
index 0000000..d91ed31
--- /dev/null
+++ b/lib/dns/tkey.c
@@ -0,0 +1,1604 @@
+/*
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0
+ *
+ * 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 https://mozilla.org/MPL/2.0/.
+ *
+ * See the COPYRIGHT file distributed with this work for additional
+ * information regarding copyright ownership.
+ */
+
+/*! \file */
+
+#include <inttypes.h>
+#include <stdbool.h>
+
+#include <isc/buffer.h>
+#include <isc/md.h>
+#include <isc/mem.h>
+#include <isc/nonce.h>
+#include <isc/print.h>
+#include <isc/random.h>
+#include <isc/string.h>
+#include <isc/util.h>
+
+#include <pk11/site.h>
+
+#include <dns/dnssec.h>
+#include <dns/fixedname.h>
+#include <dns/keyvalues.h>
+#include <dns/log.h>
+#include <dns/message.h>
+#include <dns/name.h>
+#include <dns/rdata.h>
+#include <dns/rdatalist.h>
+#include <dns/rdataset.h>
+#include <dns/rdatastruct.h>
+#include <dns/result.h>
+#include <dns/tkey.h>
+#include <dns/tsig.h>
+
+#include <dst/dst.h>
+#include <dst/gssapi.h>
+
+#include "dst_internal.h"
+
+#define TEMP_BUFFER_SZ	   8192
+#define TKEY_RANDOM_AMOUNT 16
+
+#if USE_PKCS11
+#include <pk11/pk11.h>
+#endif /* if USE_PKCS11 */
+
+#define RETERR(x)                            \
+	do {                                 \
+		result = (x);                \
+		if (result != ISC_R_SUCCESS) \
+			goto failure;        \
+	} while (0)
+
+static void
+tkey_log(const char *fmt, ...) ISC_FORMAT_PRINTF(1, 2);
+
+static void
+tkey_log(const char *fmt, ...) {
+	va_list ap;
+
+	va_start(ap, fmt);
+	isc_log_vwrite(dns_lctx, DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_REQUEST,
+		       ISC_LOG_DEBUG(4), fmt, ap);
+	va_end(ap);
+}
+
+static void
+dumpmessage(dns_message_t *msg) {
+	isc_buffer_t outbuf;
+	unsigned char *output;
+	int len = TEMP_BUFFER_SZ;
+	isc_result_t result;
+
+	for (;;) {
+		output = isc_mem_get(msg->mctx, len);
+
+		isc_buffer_init(&outbuf, output, len);
+		result = dns_message_totext(msg, &dns_master_style_debug, 0,
+					    &outbuf);
+		if (result == ISC_R_NOSPACE) {
+			isc_mem_put(msg->mctx, output, len);
+			len *= 2;
+			continue;
+		}
+
+		if (result == ISC_R_SUCCESS) {
+			tkey_log("%.*s", (int)isc_buffer_usedlength(&outbuf),
+				 (char *)isc_buffer_base(&outbuf));
+		} else {
+			tkey_log("Warning: dns_message_totext: %s",
+				 dns_result_totext(result));
+		}
+		break;
+	}
+
+	if (output != NULL) {
+		isc_mem_put(msg->mctx, output, len);
+	}
+}
+
+isc_result_t
+dns_tkeyctx_create(isc_mem_t *mctx, dns_tkeyctx_t **tctxp) {
+	dns_tkeyctx_t *tctx;
+
+	REQUIRE(mctx != NULL);
+	REQUIRE(tctxp != NULL && *tctxp == NULL);
+
+	tctx = isc_mem_get(mctx, sizeof(dns_tkeyctx_t));
+	tctx->mctx = NULL;
+	isc_mem_attach(mctx, &tctx->mctx);
+	tctx->dhkey = NULL;
+	tctx->domain = NULL;
+	tctx->gsscred = NULL;
+	tctx->gssapi_keytab = NULL;
+
+	*tctxp = tctx;
+	return (ISC_R_SUCCESS);
+}
+
+void
+dns_tkeyctx_destroy(dns_tkeyctx_t **tctxp) {
+	isc_mem_t *mctx;
+	dns_tkeyctx_t *tctx;
+
+	REQUIRE(tctxp != NULL && *tctxp != NULL);
+
+	tctx = *tctxp;
+	*tctxp = NULL;
+	mctx = tctx->mctx;
+
+	if (tctx->dhkey != NULL) {
+		dst_key_free(&tctx->dhkey);
+	}
+	if (tctx->domain != NULL) {
+		if (dns_name_dynamic(tctx->domain)) {
+			dns_name_free(tctx->domain, mctx);
+		}
+		isc_mem_put(mctx, tctx->domain, sizeof(dns_name_t));
+	}
+	if (tctx->gssapi_keytab != NULL) {
+		isc_mem_free(mctx, tctx->gssapi_keytab);
+	}
+	if (tctx->gsscred != NULL) {
+		dst_gssapi_releasecred(&tctx->gsscred);
+	}
+	isc_mem_putanddetach(&mctx, tctx, sizeof(dns_tkeyctx_t));
+}
+
+static isc_result_t
+add_rdata_to_list(dns_message_t *msg, dns_name_t *name, dns_rdata_t *rdata,
+		  uint32_t ttl, dns_namelist_t *namelist) {
+	isc_result_t result;
+	isc_region_t r, newr;
+	dns_rdata_t *newrdata = NULL;
+	dns_name_t *newname = NULL;
+	dns_rdatalist_t *newlist = NULL;
+	dns_rdataset_t *newset = NULL;
+	isc_buffer_t *tmprdatabuf = NULL;
+
+	RETERR(dns_message_gettemprdata(msg, &newrdata));
+
+	dns_rdata_toregion(rdata, &r);
+	isc_buffer_allocate(msg->mctx, &tmprdatabuf, r.length);
+	isc_buffer_availableregion(tmprdatabuf, &newr);
+	memmove(newr.base, r.base, r.length);
+	dns_rdata_fromregion(newrdata, rdata->rdclass, rdata->type, &newr);
+	dns_message_takebuffer(msg, &tmprdatabuf);
+
+	RETERR(dns_message_gettempname(msg, &newname));
+	dns_name_copynf(name, newname);
+
+	RETERR(dns_message_gettemprdatalist(msg, &newlist));
+	newlist->rdclass = newrdata->rdclass;
+	newlist->type = newrdata->type;
+	newlist->ttl = ttl;
+	ISC_LIST_APPEND(newlist->rdata, newrdata, link);
+
+	RETERR(dns_message_gettemprdataset(msg, &newset));
+	RETERR(dns_rdatalist_tordataset(newlist, newset));
+
+	ISC_LIST_INIT(newname->list);
+	ISC_LIST_APPEND(newname->list, newset, link);
+
+	ISC_LIST_APPEND(*namelist, newname, link);
+
+	return (ISC_R_SUCCESS);
+
+failure:
+	if (newrdata != NULL) {
+		if (ISC_LINK_LINKED(newrdata, link)) {
+			INSIST(newlist != NULL);
+			ISC_LIST_UNLINK(newlist->rdata, newrdata, link);
+		}
+		dns_message_puttemprdata(msg, &newrdata);
+	}
+	if (newname != NULL) {
+		dns_message_puttempname(msg, &newname);
+	}
+	if (newset != NULL) {
+		dns_rdataset_disassociate(newset);
+		dns_message_puttemprdataset(msg, &newset);
+	}
+	if (newlist != NULL) {
+		dns_message_puttemprdatalist(msg, &newlist);
+	}
+	return (result);
+}
+
+static void
+free_namelist(dns_message_t *msg, dns_namelist_t *namelist) {
+	dns_name_t *name;
+	dns_rdataset_t *set;
+
+	while (!ISC_LIST_EMPTY(*namelist)) {
+		name = ISC_LIST_HEAD(*namelist);
+		ISC_LIST_UNLINK(*namelist, name, link);
+		while (!ISC_LIST_EMPTY(name->list)) {
+			set = ISC_LIST_HEAD(name->list);
+			ISC_LIST_UNLINK(name->list, set, link);
+			if (dns_rdataset_isassociated(set)) {
+				dns_rdataset_disassociate(set);
+			}
+			dns_message_puttemprdataset(msg, &set);
+		}
+		dns_message_puttempname(msg, &name);
+	}
+}
+
+static isc_result_t
+compute_secret(isc_buffer_t *shared, isc_region_t *queryrandomness,
+	       isc_region_t *serverrandomness, isc_buffer_t *secret) {
+	isc_md_t *md;
+	isc_region_t r, r2;
+	unsigned char digests[ISC_MAX_MD_SIZE * 2];
+	unsigned char *digest1, *digest2;
+	unsigned int digestslen, digestlen1 = 0, digestlen2 = 0;
+	unsigned int i;
+	isc_result_t result;
+
+	isc_buffer_usedregion(shared, &r);
+
+	md = isc_md_new();
+	if (md == NULL) {
+		return (ISC_R_NOSPACE);
+	}
+
+	/*
+	 * MD5 ( query data | DH value ).
+	 */
+	digest1 = digests;
+
+	result = isc_md_init(md, ISC_MD_MD5);
+	if (result != ISC_R_SUCCESS) {
+		goto end;
+	}
+
+	result = isc_md_update(md, queryrandomness->base,
+			       queryrandomness->length);
+	if (result != ISC_R_SUCCESS) {
+		goto end;
+	}
+
+	result = isc_md_update(md, r.base, r.length);
+	if (result != ISC_R_SUCCESS) {
+		goto end;
+	}
+
+	result = isc_md_final(md, digest1, &digestlen1);
+	if (result != ISC_R_SUCCESS) {
+		goto end;
+	}
+
+	result = isc_md_reset(md);
+	if (result != ISC_R_SUCCESS) {
+		goto end;
+	}
+
+	/*
+	 * MD5 ( server data | DH value ).
+	 */
+	digest2 = digests + digestlen1;
+
+	result = isc_md_init(md, ISC_MD_MD5);
+	if (result != ISC_R_SUCCESS) {
+		goto end;
+	}
+
+	result = isc_md_update(md, serverrandomness->base,
+			       serverrandomness->length);
+	if (result != ISC_R_SUCCESS) {
+		goto end;
+	}
+
+	result = isc_md_update(md, r.base, r.length);
+	if (result != ISC_R_SUCCESS) {
+		goto end;
+	}
+
+	result = isc_md_final(md, digest2, &digestlen2);
+	if (result != ISC_R_SUCCESS) {
+		goto end;
+	}
+
+	isc_md_free(md);
+	md = NULL;
+
+	digestslen = digestlen1 + digestlen2;
+
+	/*
+	 * XOR ( DH value, MD5-1 | MD5-2).
+	 */
+	isc_buffer_availableregion(secret, &r);
+	isc_buffer_usedregion(shared, &r2);
+	if (r.length < digestslen || r.length < r2.length) {
+		return (ISC_R_NOSPACE);
+	}
+	if (r2.length > digestslen) {
+		memmove(r.base, r2.base, r2.length);
+		for (i = 0; i < digestslen; i++) {
+			r.base[i] ^= digests[i];
+		}
+		isc_buffer_add(secret, r2.length);
+	} else {
+		memmove(r.base, digests, digestslen);
+		for (i = 0; i < r2.length; i++) {
+			r.base[i] ^= r2.base[i];
+		}
+		isc_buffer_add(secret, digestslen);
+	}
+	result = ISC_R_SUCCESS;
+end:
+	if (md != NULL) {
+		isc_md_free(md);
+	}
+	return (result);
+}
+
+static isc_result_t
+process_dhtkey(dns_message_t *msg, dns_name_t *signer, dns_name_t *name,
+	       dns_rdata_tkey_t *tkeyin, dns_tkeyctx_t *tctx,
+	       dns_rdata_tkey_t *tkeyout, dns_tsig_keyring_t *ring,
+	       dns_namelist_t *namelist) {
+	isc_result_t result = ISC_R_SUCCESS;
+	dns_name_t *keyname, ourname;
+	dns_rdataset_t *keyset = NULL;
+	dns_rdata_t keyrdata = DNS_RDATA_INIT, ourkeyrdata = DNS_RDATA_INIT;
+	bool found_key = false, found_incompatible = false;
+	dst_key_t *pubkey = NULL;
+	isc_buffer_t ourkeybuf, *shared = NULL;
+	isc_region_t r, r2, ourkeyr;
+	unsigned char keydata[DST_KEY_MAXSIZE];
+	unsigned int sharedsize;
+	isc_buffer_t secret;
+	unsigned char *randomdata = NULL, secretdata[256];
+	dns_ttl_t ttl = 0;
+
+	if (tctx->dhkey == NULL) {
+		tkey_log("process_dhtkey: tkey-dhkey not defined");
+		tkeyout->error = dns_tsigerror_badalg;
+		return (DNS_R_REFUSED);
+	}
+
+	if (!dns_name_equal(&tkeyin->algorithm, DNS_TSIG_HMACMD5_NAME)) {
+		tkey_log("process_dhtkey: algorithms other than "
+			 "hmac-md5 are not supported");
+		tkeyout->error = dns_tsigerror_badalg;
+		return (ISC_R_SUCCESS);
+	}
+
+	/*
+	 * Look for a DH KEY record that will work with ours.
+	 */
+	for (result = dns_message_firstname(msg, DNS_SECTION_ADDITIONAL);
+	     result == ISC_R_SUCCESS && !found_key;
+	     result = dns_message_nextname(msg, DNS_SECTION_ADDITIONAL))
+	{
+		keyname = NULL;
+		dns_message_currentname(msg, DNS_SECTION_ADDITIONAL, &keyname);
+		keyset = NULL;
+		result = dns_message_findtype(keyname, dns_rdatatype_key, 0,
+					      &keyset);
+		if (result != ISC_R_SUCCESS) {
+			continue;
+		}
+
+		for (result = dns_rdataset_first(keyset);
+		     result == ISC_R_SUCCESS && !found_key;
+		     result = dns_rdataset_next(keyset))
+		{
+			dns_rdataset_current(keyset, &keyrdata);
+			pubkey = NULL;
+			result = dns_dnssec_keyfromrdata(keyname, &keyrdata,
+							 msg->mctx, &pubkey);
+			if (result != ISC_R_SUCCESS) {
+				dns_rdata_reset(&keyrdata);
+				continue;
+			}
+			if (dst_key_alg(pubkey) == DNS_KEYALG_DH) {
+				if (dst_key_paramcompare(pubkey, tctx->dhkey)) {
+					found_key = true;
+					ttl = keyset->ttl;
+					break;
+				} else {
+					found_incompatible = true;
+				}
+			}
+			dst_key_free(&pubkey);
+			dns_rdata_reset(&keyrdata);
+		}
+	}
+
+	if (!found_key) {
+		if (found_incompatible) {
+			tkey_log("process_dhtkey: found an incompatible key");
+			tkeyout->error = dns_tsigerror_badkey;
+			return (ISC_R_SUCCESS);
+		} else {
+			tkey_log("process_dhtkey: failed to find a key");
+			return (DNS_R_FORMERR);
+		}
+	}
+
+	RETERR(add_rdata_to_list(msg, keyname, &keyrdata, ttl, namelist));
+
+	isc_buffer_init(&ourkeybuf, keydata, sizeof(keydata));
+	RETERR(dst_key_todns(tctx->dhkey, &ourkeybuf));
+	isc_buffer_usedregion(&ourkeybuf, &ourkeyr);
+	dns_rdata_fromregion(&ourkeyrdata, dns_rdataclass_any,
+			     dns_rdatatype_key, &ourkeyr);
+
+	dns_name_init(&ourname, NULL);
+	dns_name_clone(dst_key_name(tctx->dhkey), &ourname);
+
+	/*
+	 * XXXBEW The TTL should be obtained from the database, if it exists.
+	 */
+	RETERR(add_rdata_to_list(msg, &ourname, &ourkeyrdata, 0, namelist));
+
+	RETERR(dst_key_secretsize(tctx->dhkey, &sharedsize));
+	isc_buffer_allocate(msg->mctx, &shared, sharedsize);
+
+	result = dst_key_computesecret(pubkey, tctx->dhkey, shared);
+	if (result != ISC_R_SUCCESS) {
+		tkey_log("process_dhtkey: failed to compute shared secret: %s",
+			 isc_result_totext(result));
+		goto failure;
+	}
+	dst_key_free(&pubkey);
+
+	isc_buffer_init(&secret, secretdata, sizeof(secretdata));
+
+	randomdata = isc_mem_get(tkeyout->mctx, TKEY_RANDOM_AMOUNT);
+
+	isc_nonce_buf(randomdata, TKEY_RANDOM_AMOUNT);
+
+	r.base = randomdata;
+	r.length = TKEY_RANDOM_AMOUNT;
+	r2.base = tkeyin->key;
+	r2.length = tkeyin->keylen;
+	RETERR(compute_secret(shared, &r2, &r, &secret));
+	isc_buffer_free(&shared);
+
+	RETERR(dns_tsigkey_create(
+		name, &tkeyin->algorithm, isc_buffer_base(&secret),
+		isc_buffer_usedlength(&secret), true, signer, tkeyin->inception,
+		tkeyin->expire, ring->mctx, ring, NULL));
+
+	/* This key is good for a long time */
+	tkeyout->inception = tkeyin->inception;
+	tkeyout->expire = tkeyin->expire;
+
+	tkeyout->key = randomdata;
+	tkeyout->keylen = TKEY_RANDOM_AMOUNT;
+
+	return (ISC_R_SUCCESS);
+
+failure:
+	if (!ISC_LIST_EMPTY(*namelist)) {
+		free_namelist(msg, namelist);
+	}
+	if (shared != NULL) {
+		isc_buffer_free(&shared);
+	}
+	if (pubkey != NULL) {
+		dst_key_free(&pubkey);
+	}
+	if (randomdata != NULL) {
+		isc_mem_put(tkeyout->mctx, randomdata, TKEY_RANDOM_AMOUNT);
+	}
+	return (result);
+}
+
+static isc_result_t
+process_gsstkey(dns_message_t *msg, dns_name_t *name, dns_rdata_tkey_t *tkeyin,
+		dns_tkeyctx_t *tctx, dns_rdata_tkey_t *tkeyout,
+		dns_tsig_keyring_t *ring) {
+	isc_result_t result = ISC_R_SUCCESS;
+	dst_key_t *dstkey = NULL;
+	dns_tsigkey_t *tsigkey = NULL;
+	dns_fixedname_t fixed;
+	dns_name_t *principal;
+	isc_stdtime_t now;
+	isc_region_t intoken;
+	isc_buffer_t *outtoken = NULL;
+	dns_gss_ctx_id_t gss_ctx = NULL;
+
+	/*
+	 * You have to define either a gss credential (principal) to
+	 * accept with tkey-gssapi-credential, or you have to
+	 * configure a specific keytab (with tkey-gssapi-keytab) in
+	 * order to use gsstkey.
+	 */
+	if (tctx->gsscred == NULL && tctx->gssapi_keytab == NULL) {
+		tkey_log("process_gsstkey(): no tkey-gssapi-credential "
+			 "or tkey-gssapi-keytab configured");
+		return (ISC_R_NOPERM);
+	}
+
+	if (!dns_name_equal(&tkeyin->algorithm, DNS_TSIG_GSSAPI_NAME) &&
+	    !dns_name_equal(&tkeyin->algorithm, DNS_TSIG_GSSAPIMS_NAME))
+	{
+		tkeyout->error = dns_tsigerror_badalg;
+		tkey_log("process_gsstkey(): dns_tsigerror_badalg"); /* XXXSRA
+								      */
+		return (ISC_R_SUCCESS);
+	}
+
+	/*
+	 * XXXDCL need to check for key expiry per 4.1.1
+	 * XXXDCL need a way to check fully established, perhaps w/key_flags
+	 */
+
+	intoken.base = tkeyin->key;
+	intoken.length = tkeyin->keylen;
+
+	result = dns_tsigkey_find(&tsigkey, name, &tkeyin->algorithm, ring);
+	if (result == ISC_R_SUCCESS) {
+		gss_ctx = dst_key_getgssctx(tsigkey->key);
+	}
+
+	principal = dns_fixedname_initname(&fixed);
+
+	/*
+	 * Note that tctx->gsscred may be NULL if tctx->gssapi_keytab is set
+	 */
+	result = dst_gssapi_acceptctx(tctx->gsscred, tctx->gssapi_keytab,
+				      &intoken, &outtoken, &gss_ctx, principal,
+				      tctx->mctx);
+	if (result == DNS_R_INVALIDTKEY) {
+		if (tsigkey != NULL) {
+			dns_tsigkey_detach(&tsigkey);
+		}
+		tkeyout->error = dns_tsigerror_badkey;
+		tkey_log("process_gsstkey(): dns_tsigerror_badkey"); /* XXXSRA
+								      */
+		return (ISC_R_SUCCESS);
+	}
+	if (result != DNS_R_CONTINUE && result != ISC_R_SUCCESS) {
+		goto failure;
+	}
+	/*
+	 * XXXDCL Section 4.1.3: Limit GSS_S_CONTINUE_NEEDED to 10 times.
+	 */
+
+	isc_stdtime_get(&now);
+
+	if (dns_name_countlabels(principal) == 0U) {
+		if (tsigkey != NULL) {
+			dns_tsigkey_detach(&tsigkey);
+		}
+	} else if (tsigkey == NULL) {
+#ifdef GSSAPI
+		OM_uint32 gret, minor, lifetime;
+#endif /* ifdef GSSAPI */
+		uint32_t expire;
+
+		RETERR(dst_key_fromgssapi(name, gss_ctx, ring->mctx, &dstkey,
+					  &intoken));
+		/*
+		 * Limit keys to 1 hour or the context's lifetime whichever
+		 * is smaller.
+		 */
+		expire = now + 3600;
+#ifdef GSSAPI
+		gret = gss_context_time(&minor, gss_ctx, &lifetime);
+		if (gret == GSS_S_COMPLETE && now + lifetime < expire) {
+			expire = now + lifetime;
+		}
+#endif /* ifdef GSSAPI */
+		RETERR(dns_tsigkey_createfromkey(
+			name, &tkeyin->algorithm, dstkey, true, principal, now,
+			expire, ring->mctx, ring, &tsigkey));
+		dst_key_free(&dstkey);
+		tkeyout->inception = now;
+		tkeyout->expire = expire;
+	} else {
+		tkeyout->inception = tsigkey->inception;
+		tkeyout->expire = tsigkey->expire;
+	}
+
+	if (outtoken) {
+		tkeyout->key = isc_mem_get(tkeyout->mctx,
+					   isc_buffer_usedlength(outtoken));
+		tkeyout->keylen = isc_buffer_usedlength(outtoken);
+		memmove(tkeyout->key, isc_buffer_base(outtoken),
+			isc_buffer_usedlength(outtoken));
+		isc_buffer_free(&outtoken);
+	} else {
+		tkeyout->key = isc_mem_get(tkeyout->mctx, tkeyin->keylen);
+		tkeyout->keylen = tkeyin->keylen;
+		memmove(tkeyout->key, tkeyin->key, tkeyin->keylen);
+	}
+
+	tkeyout->error = dns_rcode_noerror;
+
+	tkey_log("process_gsstkey(): dns_tsigerror_noerror"); /* XXXSRA */
+
+	/*
+	 * We found a TKEY to respond with.  If the request is not TSIG signed,
+	 * we need to make sure the response is signed (see RFC 3645, Section
+	 * 2.2).
+	 */
+	if (tsigkey != NULL) {
+		if (msg->tsigkey == NULL && msg->sig0key == NULL) {
+			dns_message_settsigkey(msg, tsigkey);
+		}
+		dns_tsigkey_detach(&tsigkey);
+	}
+
+	return (ISC_R_SUCCESS);
+
+failure:
+	if (tsigkey != NULL) {
+		dns_tsigkey_detach(&tsigkey);
+	}
+
+	if (dstkey != NULL) {
+		dst_key_free(&dstkey);
+	}
+
+	if (outtoken != NULL) {
+		isc_buffer_free(&outtoken);
+	}
+
+	tkey_log("process_gsstkey(): %s", isc_result_totext(result)); /* XXXSRA
+								       */
+
+	return (result);
+}
+
+static isc_result_t
+process_deletetkey(dns_name_t *signer, dns_name_t *name,
+		   dns_rdata_tkey_t *tkeyin, dns_rdata_tkey_t *tkeyout,
+		   dns_tsig_keyring_t *ring) {
+	isc_result_t result;
+	dns_tsigkey_t *tsigkey = NULL;
+	const dns_name_t *identity;
+
+	result = dns_tsigkey_find(&tsigkey, name, &tkeyin->algorithm, ring);
+	if (result != ISC_R_SUCCESS) {
+		tkeyout->error = dns_tsigerror_badname;
+		return (ISC_R_SUCCESS);
+	}
+
+	/*
+	 * Only allow a delete if the identity that created the key is the
+	 * same as the identity that signed the message.
+	 */
+	identity = dns_tsigkey_identity(tsigkey);
+	if (identity == NULL || !dns_name_equal(identity, signer)) {
+		dns_tsigkey_detach(&tsigkey);
+		return (DNS_R_REFUSED);
+	}
+
+	/*
+	 * Set the key to be deleted when no references are left.  If the key
+	 * was not generated with TKEY and is in the config file, it may be
+	 * reloaded later.
+	 */
+	dns_tsigkey_setdeleted(tsigkey);
+
+	/* Release the reference */
+	dns_tsigkey_detach(&tsigkey);
+
+	return (ISC_R_SUCCESS);
+}
+
+isc_result_t
+dns_tkey_processquery(dns_message_t *msg, dns_tkeyctx_t *tctx,
+		      dns_tsig_keyring_t *ring) {
+	isc_result_t result = ISC_R_SUCCESS;
+	dns_rdata_tkey_t tkeyin, tkeyout;
+	bool freetkeyin = false;
+	dns_name_t *qname, *name, *keyname, *signer, tsigner;
+	dns_fixedname_t fkeyname;
+	dns_rdataset_t *tkeyset;
+	dns_rdata_t rdata;
+	dns_namelist_t namelist;
+	char tkeyoutdata[512];
+	isc_buffer_t tkeyoutbuf;
+
+	REQUIRE(msg != NULL);
+	REQUIRE(tctx != NULL);
+	REQUIRE(ring != NULL);
+
+	ISC_LIST_INIT(namelist);
+
+	/*
+	 * Interpret the question section.
+	 */
+	result = dns_message_firstname(msg, DNS_SECTION_QUESTION);
+	if (result != ISC_R_SUCCESS) {
+		return (DNS_R_FORMERR);
+	}
+
+	qname = NULL;
+	dns_message_currentname(msg, DNS_SECTION_QUESTION, &qname);
+
+	/*
+	 * Look for a TKEY record that matches the question.
+	 */
+	tkeyset = NULL;
+	name = NULL;
+	result = dns_message_findname(msg, DNS_SECTION_ADDITIONAL, qname,
+				      dns_rdatatype_tkey, 0, &name, &tkeyset);
+	if (result != ISC_R_SUCCESS) {
+		/*
+		 * Try the answer section, since that's where Win2000
+		 * puts it.
+		 */
+		name = NULL;
+		if (dns_message_findname(msg, DNS_SECTION_ANSWER, qname,
+					 dns_rdatatype_tkey, 0, &name,
+					 &tkeyset) != ISC_R_SUCCESS)
+		{
+			result = DNS_R_FORMERR;
+			tkey_log("dns_tkey_processquery: couldn't find a TKEY "
+				 "matching the question");
+			goto failure;
+		}
+	}
+	result = dns_rdataset_first(tkeyset);
+	if (result != ISC_R_SUCCESS) {
+		result = DNS_R_FORMERR;
+		goto failure;
+	}
+	dns_rdata_init(&rdata);
+	dns_rdataset_current(tkeyset, &rdata);
+
+	RETERR(dns_rdata_tostruct(&rdata, &tkeyin, NULL));
+	freetkeyin = true;
+
+	if (tkeyin.error != dns_rcode_noerror) {
+		result = DNS_R_FORMERR;
+		goto failure;
+	}
+
+	/*
+	 * Before we go any farther, verify that the message was signed.
+	 * GSSAPI TKEY doesn't require a signature, the rest do.
+	 */
+	dns_name_init(&tsigner, NULL);
+	result = dns_message_signer(msg, &tsigner);
+	if (result != ISC_R_SUCCESS) {
+		if (tkeyin.mode == DNS_TKEYMODE_GSSAPI &&
+		    result == ISC_R_NOTFOUND)
+		{
+			signer = NULL;
+		} else {
+			tkey_log("dns_tkey_processquery: query was not "
+				 "properly signed - rejecting");
+			result = DNS_R_FORMERR;
+			goto failure;
+		}
+	} else {
+		signer = &tsigner;
+	}
+
+	tkeyout.common.rdclass = tkeyin.common.rdclass;
+	tkeyout.common.rdtype = tkeyin.common.rdtype;
+	ISC_LINK_INIT(&tkeyout.common, link);
+	tkeyout.mctx = msg->mctx;
+
+	dns_name_init(&tkeyout.algorithm, NULL);
+	dns_name_clone(&tkeyin.algorithm, &tkeyout.algorithm);
+
+	tkeyout.inception = tkeyout.expire = 0;
+	tkeyout.mode = tkeyin.mode;
+	tkeyout.error = 0;
+	tkeyout.keylen = tkeyout.otherlen = 0;
+	tkeyout.key = tkeyout.other = NULL;
+
+	/*
+	 * A delete operation must have a fully specified key name.  If this
+	 * is not a delete, we do the following:
+	 * if (qname != ".")
+	 *	keyname = qname + defaultdomain
+	 * else
+	 *	keyname = <random hex> + defaultdomain
+	 */
+	if (tkeyin.mode != DNS_TKEYMODE_DELETE) {
+		dns_tsigkey_t *tsigkey = NULL;
+
+		if (tctx->domain == NULL && tkeyin.mode != DNS_TKEYMODE_GSSAPI)
+		{
+			tkey_log("dns_tkey_processquery: tkey-domain not set");
+			result = DNS_R_REFUSED;
+			goto failure;
+		}
+
+		keyname = dns_fixedname_initname(&fkeyname);
+
+		if (!dns_name_equal(qname, dns_rootname)) {
+			unsigned int n = dns_name_countlabels(qname);
+			dns_name_copynf(qname, keyname);
+			dns_name_getlabelsequence(keyname, 0, n - 1, keyname);
+		} else {
+			static char hexdigits[16] = { '0', '1', '2', '3',
+						      '4', '5', '6', '7',
+						      '8', '9', 'A', 'B',
+						      'C', 'D', 'E', 'F' };
+			unsigned char randomdata[16];
+			char randomtext[32];
+			isc_buffer_t b;
+			unsigned int i, j;
+
+			isc_nonce_buf(randomdata, sizeof(randomdata));
+
+			for (i = 0, j = 0; i < sizeof(randomdata); i++) {
+				unsigned char val = randomdata[i];
+				randomtext[j++] = hexdigits[val >> 4];
+				randomtext[j++] = hexdigits[val & 0xF];
+			}
+			isc_buffer_init(&b, randomtext, sizeof(randomtext));
+			isc_buffer_add(&b, sizeof(randomtext));
+			result = dns_name_fromtext(keyname, &b, NULL, 0, NULL);
+			if (result != ISC_R_SUCCESS) {
+				goto failure;
+			}
+		}
+
+		if (tkeyin.mode == DNS_TKEYMODE_GSSAPI) {
+			/* Yup.  This is a hack */
+			result = dns_name_concatenate(keyname, dns_rootname,
+						      keyname, NULL);
+			if (result != ISC_R_SUCCESS) {
+				goto failure;
+			}
+		} else {
+			result = dns_name_concatenate(keyname, tctx->domain,
+						      keyname, NULL);
+			if (result != ISC_R_SUCCESS) {
+				goto failure;
+			}
+		}
+
+		result = dns_tsigkey_find(&tsigkey, keyname, NULL, ring);
+
+		if (result == ISC_R_SUCCESS) {
+			tkeyout.error = dns_tsigerror_badname;
+			dns_tsigkey_detach(&tsigkey);
+			goto failure_with_tkey;
+		} else if (result != ISC_R_NOTFOUND) {
+			goto failure;
+		}
+	} else {
+		keyname = qname;
+	}
+
+	switch (tkeyin.mode) {
+	case DNS_TKEYMODE_DIFFIEHELLMAN:
+		tkeyout.error = dns_rcode_noerror;
+		RETERR(process_dhtkey(msg, signer, keyname, &tkeyin, tctx,
+				      &tkeyout, ring, &namelist));
+		break;
+	case DNS_TKEYMODE_GSSAPI:
+		tkeyout.error = dns_rcode_noerror;
+		RETERR(process_gsstkey(msg, keyname, &tkeyin, tctx, &tkeyout,
+				       ring));
+		break;
+	case DNS_TKEYMODE_DELETE:
+		tkeyout.error = dns_rcode_noerror;
+		RETERR(process_deletetkey(signer, keyname, &tkeyin, &tkeyout,
+					  ring));
+		break;
+	case DNS_TKEYMODE_SERVERASSIGNED:
+	case DNS_TKEYMODE_RESOLVERASSIGNED:
+		result = DNS_R_NOTIMP;
+		goto failure;
+	default:
+		tkeyout.error = dns_tsigerror_badmode;
+	}
+
+failure_with_tkey:
+
+	dns_rdata_init(&rdata);
+	isc_buffer_init(&tkeyoutbuf, tkeyoutdata, sizeof(tkeyoutdata));
+	result = dns_rdata_fromstruct(&rdata, tkeyout.common.rdclass,
+				      tkeyout.common.rdtype, &tkeyout,
+				      &tkeyoutbuf);
+
+	if (freetkeyin) {
+		dns_rdata_freestruct(&tkeyin);
+		freetkeyin = false;
+	}
+
+	if (tkeyout.key != NULL) {
+		isc_mem_put(tkeyout.mctx, tkeyout.key, tkeyout.keylen);
+	}
+	if (tkeyout.other != NULL) {
+		isc_mem_put(tkeyout.mctx, tkeyout.other, tkeyout.otherlen);
+	}
+	if (result != ISC_R_SUCCESS) {
+		goto failure;
+	}
+
+	RETERR(add_rdata_to_list(msg, keyname, &rdata, 0, &namelist));
+
+	RETERR(dns_message_reply(msg, true));
+
+	name = ISC_LIST_HEAD(namelist);
+	while (name != NULL) {
+		dns_name_t *next = ISC_LIST_NEXT(name, link);
+		ISC_LIST_UNLINK(namelist, name, link);
+		dns_message_addname(msg, name, DNS_SECTION_ANSWER);
+		name = next;
+	}
+
+	return (ISC_R_SUCCESS);
+
+failure:
+
+	if (freetkeyin) {
+		dns_rdata_freestruct(&tkeyin);
+	}
+	if (!ISC_LIST_EMPTY(namelist)) {
+		free_namelist(msg, &namelist);
+	}
+	return (result);
+}
+
+static isc_result_t
+buildquery(dns_message_t *msg, const dns_name_t *name, dns_rdata_tkey_t *tkey,
+	   bool win2k) {
+	dns_name_t *qname = NULL, *aname = NULL;
+	dns_rdataset_t *question = NULL, *tkeyset = NULL;
+	dns_rdatalist_t *tkeylist = NULL;
+	dns_rdata_t *rdata = NULL;
+	isc_buffer_t *dynbuf = NULL;
+	isc_result_t result;
+	unsigned int len;
+
+	REQUIRE(msg != NULL);
+	REQUIRE(name != NULL);
+	REQUIRE(tkey != NULL);
+
+	RETERR(dns_message_gettempname(msg, &qname));
+	RETERR(dns_message_gettempname(msg, &aname));
+
+	RETERR(dns_message_gettemprdataset(msg, &question));
+	dns_rdataset_makequestion(question, dns_rdataclass_any,
+				  dns_rdatatype_tkey);
+
+	len = 16 + tkey->algorithm.length + tkey->keylen + tkey->otherlen;
+	isc_buffer_allocate(msg->mctx, &dynbuf, len);
+	RETERR(dns_message_gettemprdata(msg, &rdata));
+
+	RETERR(dns_rdata_fromstruct(rdata, dns_rdataclass_any,
+				    dns_rdatatype_tkey, tkey, dynbuf));
+	dns_message_takebuffer(msg, &dynbuf);
+
+	RETERR(dns_message_gettemprdatalist(msg, &tkeylist));
+	tkeylist->rdclass = dns_rdataclass_any;
+	tkeylist->type = dns_rdatatype_tkey;
+	ISC_LIST_APPEND(tkeylist->rdata, rdata, link);
+
+	RETERR(dns_message_gettemprdataset(msg, &tkeyset));
+	RETERR(dns_rdatalist_tordataset(tkeylist, tkeyset));
+
+	dns_name_copynf(name, qname);
+	dns_name_copynf(name, aname);
+
+	ISC_LIST_APPEND(qname->list, question, link);
+	ISC_LIST_APPEND(aname->list, tkeyset, link);
+
+	dns_message_addname(msg, qname, DNS_SECTION_QUESTION);
+
+	/*
+	 * Windows 2000 needs this in the answer section, not the additional
+	 * section where the RFC specifies.
+	 */
+	if (win2k) {
+		dns_message_addname(msg, aname, DNS_SECTION_ANSWER);
+	} else {
+		dns_message_addname(msg, aname, DNS_SECTION_ADDITIONAL);
+	}
+
+	return (ISC_R_SUCCESS);
+
+failure:
+	if (qname != NULL) {
+		dns_message_puttempname(msg, &qname);
+	}
+	if (aname != NULL) {
+		dns_message_puttempname(msg, &aname);
+	}
+	if (question != NULL) {
+		dns_rdataset_disassociate(question);
+		dns_message_puttemprdataset(msg, &question);
+	}
+	if (dynbuf != NULL) {
+		isc_buffer_free(&dynbuf);
+	}
+	if (rdata != NULL) {
+		dns_message_puttemprdata(msg, &rdata);
+	}
+	if (tkeylist != NULL) {
+		dns_message_puttemprdatalist(msg, &tkeylist);
+	}
+	if (tkeyset != NULL) {
+		if (dns_rdataset_isassociated(tkeyset)) {
+			dns_rdataset_disassociate(tkeyset);
+		}
+		dns_message_puttemprdataset(msg, &tkeyset);
+	}
+	return (result);
+}
+
+isc_result_t
+dns_tkey_builddhquery(dns_message_t *msg, dst_key_t *key,
+		      const dns_name_t *name, const dns_name_t *algorithm,
+		      isc_buffer_t *nonce, uint32_t lifetime) {
+	dns_rdata_tkey_t tkey;
+	dns_rdata_t *rdata = NULL;
+	isc_buffer_t *dynbuf = NULL;
+	isc_region_t r;
+	dns_name_t keyname;
+	dns_namelist_t namelist;
+	isc_result_t result;
+	isc_stdtime_t now;
+	dns_name_t *item;
+
+	REQUIRE(msg != NULL);
+	REQUIRE(key != NULL);
+	REQUIRE(dst_key_alg(key) == DNS_KEYALG_DH);
+	REQUIRE(dst_key_isprivate(key));
+	REQUIRE(name != NULL);
+	REQUIRE(algorithm != NULL);
+
+	tkey.common.rdclass = dns_rdataclass_any;
+	tkey.common.rdtype = dns_rdatatype_tkey;
+	ISC_LINK_INIT(&tkey.common, link);
+	tkey.mctx = msg->mctx;
+	dns_name_init(&tkey.algorithm, NULL);
+	dns_name_clone(algorithm, &tkey.algorithm);
+	isc_stdtime_get(&now);
+	tkey.inception = now;
+	tkey.expire = now + lifetime;
+	tkey.mode = DNS_TKEYMODE_DIFFIEHELLMAN;
+	if (nonce != NULL) {
+		isc_buffer_usedregion(nonce, &r);
+	} else {
+		r.base = NULL;
+		r.length = 0;
+	}
+	tkey.error = 0;
+	tkey.key = r.base;
+	tkey.keylen = r.length;
+	tkey.other = NULL;
+	tkey.otherlen = 0;
+
+	RETERR(buildquery(msg, name, &tkey, false));
+
+	RETERR(dns_message_gettemprdata(msg, &rdata));
+	isc_buffer_allocate(msg->mctx, &dynbuf, 1024);
+	RETERR(dst_key_todns(key, dynbuf));
+	isc_buffer_usedregion(dynbuf, &r);
+	dns_rdata_fromregion(rdata, dns_rdataclass_any, dns_rdatatype_key, &r);
+	dns_message_takebuffer(msg, &dynbuf);
+
+	dns_name_init(&keyname, NULL);
+	dns_name_clone(dst_key_name(key), &keyname);
+
+	ISC_LIST_INIT(namelist);
+	RETERR(add_rdata_to_list(msg, &keyname, rdata, 0, &namelist));
+	item = ISC_LIST_HEAD(namelist);
+	while (item != NULL) {
+		dns_name_t *next = ISC_LIST_NEXT(item, link);
+		ISC_LIST_UNLINK(namelist, item, link);
+		dns_message_addname(msg, item, DNS_SECTION_ADDITIONAL);
+		item = next;
+	}
+
+	return (ISC_R_SUCCESS);
+
+failure:
+
+	if (dynbuf != NULL) {
+		isc_buffer_free(&dynbuf);
+	}
+	return (result);
+}
+
+isc_result_t
+dns_tkey_buildgssquery(dns_message_t *msg, const dns_name_t *name,
+		       const dns_name_t *gname, isc_buffer_t *intoken,
+		       uint32_t lifetime, dns_gss_ctx_id_t *context, bool win2k,
+		       isc_mem_t *mctx, char **err_message) {
+	dns_rdata_tkey_t tkey;
+	isc_result_t result;
+	isc_stdtime_t now;
+	isc_buffer_t token;
+	unsigned char array[TEMP_BUFFER_SZ];
+
+	UNUSED(intoken);
+
+	REQUIRE(msg != NULL);
+	REQUIRE(name != NULL);
+	REQUIRE(gname != NULL);
+	REQUIRE(context != NULL);
+	REQUIRE(mctx != NULL);
+
+	isc_buffer_init(&token, array, sizeof(array));
+	result = dst_gssapi_initctx(gname, NULL, &token, context, mctx,
+				    err_message);
+	if (result != DNS_R_CONTINUE && result != ISC_R_SUCCESS) {
+		return (result);
+	}
+
+	tkey.common.rdclass = dns_rdataclass_any;
+	tkey.common.rdtype = dns_rdatatype_tkey;
+	ISC_LINK_INIT(&tkey.common, link);
+	tkey.mctx = NULL;
+	dns_name_init(&tkey.algorithm, NULL);
+
+	if (win2k) {
+		dns_name_clone(DNS_TSIG_GSSAPIMS_NAME, &tkey.algorithm);
+	} else {
+		dns_name_clone(DNS_TSIG_GSSAPI_NAME, &tkey.algorithm);
+	}
+
+	isc_stdtime_get(&now);
+	tkey.inception = now;
+	tkey.expire = now + lifetime;
+	tkey.mode = DNS_TKEYMODE_GSSAPI;
+	tkey.error = 0;
+	tkey.key = isc_buffer_base(&token);
+	tkey.keylen = isc_buffer_usedlength(&token);
+	tkey.other = NULL;
+	tkey.otherlen = 0;
+
+	return (buildquery(msg, name, &tkey, win2k));
+}
+
+isc_result_t
+dns_tkey_builddeletequery(dns_message_t *msg, dns_tsigkey_t *key) {
+	dns_rdata_tkey_t tkey;
+
+	REQUIRE(msg != NULL);
+	REQUIRE(key != NULL);
+
+	tkey.common.rdclass = dns_rdataclass_any;
+	tkey.common.rdtype = dns_rdatatype_tkey;
+	ISC_LINK_INIT(&tkey.common, link);
+	tkey.mctx = msg->mctx;
+	dns_name_init(&tkey.algorithm, NULL);
+	dns_name_clone(key->algorithm, &tkey.algorithm);
+	tkey.inception = tkey.expire = 0;
+	tkey.mode = DNS_TKEYMODE_DELETE;
+	tkey.error = 0;
+	tkey.keylen = tkey.otherlen = 0;
+	tkey.key = tkey.other = NULL;
+
+	return (buildquery(msg, &key->name, &tkey, false));
+}
+
+static isc_result_t
+find_tkey(dns_message_t *msg, dns_name_t **name, dns_rdata_t *rdata,
+	  int section) {
+	dns_rdataset_t *tkeyset;
+	isc_result_t result;
+
+	result = dns_message_firstname(msg, section);
+	while (result == ISC_R_SUCCESS) {
+		*name = NULL;
+		dns_message_currentname(msg, section, name);
+		tkeyset = NULL;
+		result = dns_message_findtype(*name, dns_rdatatype_tkey, 0,
+					      &tkeyset);
+		if (result == ISC_R_SUCCESS) {
+			result = dns_rdataset_first(tkeyset);
+			if (result != ISC_R_SUCCESS) {
+				return (result);
+			}
+			dns_rdataset_current(tkeyset, rdata);
+			return (ISC_R_SUCCESS);
+		}
+		result = dns_message_nextname(msg, section);
+	}
+	if (result == ISC_R_NOMORE) {
+		return (ISC_R_NOTFOUND);
+	}
+	return (result);
+}
+
+isc_result_t
+dns_tkey_processdhresponse(dns_message_t *qmsg, dns_message_t *rmsg,
+			   dst_key_t *key, isc_buffer_t *nonce,
+			   dns_tsigkey_t **outkey, dns_tsig_keyring_t *ring) {
+	dns_rdata_t qtkeyrdata = DNS_RDATA_INIT, rtkeyrdata = DNS_RDATA_INIT;
+	dns_name_t keyname, *tkeyname, *theirkeyname, *ourkeyname, *tempname;
+	dns_rdataset_t *theirkeyset = NULL, *ourkeyset = NULL;
+	dns_rdata_t theirkeyrdata = DNS_RDATA_INIT;
+	dst_key_t *theirkey = NULL;
+	dns_rdata_tkey_t qtkey, rtkey;
+	unsigned char secretdata[256];
+	unsigned int sharedsize;
+	isc_buffer_t *shared = NULL, secret;
+	isc_region_t r, r2;
+	isc_result_t result;
+	bool freertkey = false;
+
+	REQUIRE(qmsg != NULL);
+	REQUIRE(rmsg != NULL);
+	REQUIRE(key != NULL);
+	REQUIRE(dst_key_alg(key) == DNS_KEYALG_DH);
+	REQUIRE(dst_key_isprivate(key));
+	if (outkey != NULL) {
+		REQUIRE(*outkey == NULL);
+	}
+
+	if (rmsg->rcode != dns_rcode_noerror) {
+		return (ISC_RESULTCLASS_DNSRCODE + rmsg->rcode);
+	}
+	RETERR(find_tkey(rmsg, &tkeyname, &rtkeyrdata, DNS_SECTION_ANSWER));
+	RETERR(dns_rdata_tostruct(&rtkeyrdata, &rtkey, NULL));
+	freertkey = true;
+
+	RETERR(find_tkey(qmsg, &tempname, &qtkeyrdata, DNS_SECTION_ADDITIONAL));
+	RETERR(dns_rdata_tostruct(&qtkeyrdata, &qtkey, NULL));
+
+	if (rtkey.error != dns_rcode_noerror ||
+	    rtkey.mode != DNS_TKEYMODE_DIFFIEHELLMAN ||
+	    rtkey.mode != qtkey.mode ||
+	    !dns_name_equal(&rtkey.algorithm, &qtkey.algorithm) ||
+	    rmsg->rcode != dns_rcode_noerror)
+	{
+		tkey_log("dns_tkey_processdhresponse: tkey mode invalid "
+			 "or error set(1)");
+		result = DNS_R_INVALIDTKEY;
+		dns_rdata_freestruct(&qtkey);
+		goto failure;
+	}
+
+	dns_rdata_freestruct(&qtkey);
+
+	dns_name_init(&keyname, NULL);
+	dns_name_clone(dst_key_name(key), &keyname);
+
+	ourkeyname = NULL;
+	ourkeyset = NULL;
+	RETERR(dns_message_findname(rmsg, DNS_SECTION_ANSWER, &keyname,
+				    dns_rdatatype_key, 0, &ourkeyname,
+				    &ourkeyset));
+
+	result = dns_message_firstname(rmsg, DNS_SECTION_ANSWER);
+	while (result == ISC_R_SUCCESS) {
+		theirkeyname = NULL;
+		dns_message_currentname(rmsg, DNS_SECTION_ANSWER,
+					&theirkeyname);
+		if (dns_name_equal(theirkeyname, ourkeyname)) {
+			goto next;
+		}
+		theirkeyset = NULL;
+		result = dns_message_findtype(theirkeyname, dns_rdatatype_key,
+					      0, &theirkeyset);
+		if (result == ISC_R_SUCCESS) {
+			RETERR(dns_rdataset_first(theirkeyset));
+			break;
+		}
+	next:
+		result = dns_message_nextname(rmsg, DNS_SECTION_ANSWER);
+	}
+
+	if (theirkeyset == NULL) {
+		tkey_log("dns_tkey_processdhresponse: failed to find server "
+			 "key");
+		result = ISC_R_NOTFOUND;
+		goto failure;
+	}
+
+	dns_rdataset_current(theirkeyset, &theirkeyrdata);
+	RETERR(dns_dnssec_keyfromrdata(theirkeyname, &theirkeyrdata, rmsg->mctx,
+				       &theirkey));
+
+	RETERR(dst_key_secretsize(key, &sharedsize));
+	isc_buffer_allocate(rmsg->mctx, &shared, sharedsize);
+
+	RETERR(dst_key_computesecret(theirkey, key, shared));
+
+	isc_buffer_init(&secret, secretdata, sizeof(secretdata));
+
+	r.base = rtkey.key;
+	r.length = rtkey.keylen;
+	if (nonce != NULL) {
+		isc_buffer_usedregion(nonce, &r2);
+	} else {
+		r2.base = NULL;
+		r2.length = 0;
+	}
+	RETERR(compute_secret(shared, &r2, &r, &secret));
+
+	isc_buffer_usedregion(&secret, &r);
+	result = dns_tsigkey_create(tkeyname, &rtkey.algorithm, r.base,
+				    r.length, true, NULL, rtkey.inception,
+				    rtkey.expire, rmsg->mctx, ring, outkey);
+	isc_buffer_free(&shared);
+	dns_rdata_freestruct(&rtkey);
+	dst_key_free(&theirkey);
+	return (result);
+
+failure:
+	if (shared != NULL) {
+		isc_buffer_free(&shared);
+	}
+
+	if (theirkey != NULL) {
+		dst_key_free(&theirkey);
+	}
+
+	if (freertkey) {
+		dns_rdata_freestruct(&rtkey);
+	}
+
+	return (result);
+}
+
+isc_result_t
+dns_tkey_processgssresponse(dns_message_t *qmsg, dns_message_t *rmsg,
+			    const dns_name_t *gname, dns_gss_ctx_id_t *context,
+			    isc_buffer_t *outtoken, dns_tsigkey_t **outkey,
+			    dns_tsig_keyring_t *ring, char **err_message) {
+	dns_rdata_t rtkeyrdata = DNS_RDATA_INIT, qtkeyrdata = DNS_RDATA_INIT;
+	dns_name_t *tkeyname;
+	dns_rdata_tkey_t rtkey, qtkey;
+	dst_key_t *dstkey = NULL;
+	isc_buffer_t intoken;
+	isc_result_t result;
+	unsigned char array[TEMP_BUFFER_SZ];
+
+	REQUIRE(outtoken != NULL);
+	REQUIRE(qmsg != NULL);
+	REQUIRE(rmsg != NULL);
+	REQUIRE(gname != NULL);
+	REQUIRE(ring != NULL);
+	if (outkey != NULL) {
+		REQUIRE(*outkey == NULL);
+	}
+
+	if (rmsg->rcode != dns_rcode_noerror) {
+		return (ISC_RESULTCLASS_DNSRCODE + rmsg->rcode);
+	}
+	RETERR(find_tkey(rmsg, &tkeyname, &rtkeyrdata, DNS_SECTION_ANSWER));
+	RETERR(dns_rdata_tostruct(&rtkeyrdata, &rtkey, NULL));
+
+	/*
+	 * Win2k puts the item in the ANSWER section, while the RFC
+	 * specifies it should be in the ADDITIONAL section.  Check first
+	 * where it should be, and then where it may be.
+	 */
+	result = find_tkey(qmsg, &tkeyname, &qtkeyrdata,
+			   DNS_SECTION_ADDITIONAL);
+	if (result == ISC_R_NOTFOUND) {
+		result = find_tkey(qmsg, &tkeyname, &qtkeyrdata,
+				   DNS_SECTION_ANSWER);
+	}
+	if (result != ISC_R_SUCCESS) {
+		goto failure;
+	}
+
+	RETERR(dns_rdata_tostruct(&qtkeyrdata, &qtkey, NULL));
+
+	if (rtkey.error != dns_rcode_noerror ||
+	    rtkey.mode != DNS_TKEYMODE_GSSAPI ||
+	    !dns_name_equal(&rtkey.algorithm, &qtkey.algorithm))
+	{
+		tkey_log("dns_tkey_processgssresponse: tkey mode invalid "
+			 "or error set(2) %d",
+			 rtkey.error);
+		dumpmessage(qmsg);
+		dumpmessage(rmsg);
+		result = DNS_R_INVALIDTKEY;
+		goto failure;
+	}
+
+	isc_buffer_init(outtoken, array, sizeof(array));
+	isc_buffer_init(&intoken, rtkey.key, rtkey.keylen);
+	RETERR(dst_gssapi_initctx(gname, &intoken, outtoken, context,
+				  ring->mctx, err_message));
+
+	RETERR(dst_key_fromgssapi(dns_rootname, *context, rmsg->mctx, &dstkey,
+				  NULL));
+
+	RETERR(dns_tsigkey_createfromkey(
+		tkeyname, DNS_TSIG_GSSAPI_NAME, dstkey, false, NULL,
+		rtkey.inception, rtkey.expire, ring->mctx, ring, outkey));
+	dst_key_free(&dstkey);
+	dns_rdata_freestruct(&rtkey);
+	return (result);
+
+failure:
+	/*
+	 * XXXSRA This probably leaks memory from rtkey and qtkey.
+	 */
+	if (dstkey != NULL) {
+		dst_key_free(&dstkey);
+	}
+	return (result);
+}
+
+isc_result_t
+dns_tkey_processdeleteresponse(dns_message_t *qmsg, dns_message_t *rmsg,
+			       dns_tsig_keyring_t *ring) {
+	dns_rdata_t qtkeyrdata = DNS_RDATA_INIT, rtkeyrdata = DNS_RDATA_INIT;
+	dns_name_t *tkeyname, *tempname;
+	dns_rdata_tkey_t qtkey, rtkey;
+	dns_tsigkey_t *tsigkey = NULL;
+	isc_result_t result;
+
+	REQUIRE(qmsg != NULL);
+	REQUIRE(rmsg != NULL);
+
+	if (rmsg->rcode != dns_rcode_noerror) {
+		return (ISC_RESULTCLASS_DNSRCODE + rmsg->rcode);
+	}
+
+	RETERR(find_tkey(rmsg, &tkeyname, &rtkeyrdata, DNS_SECTION_ANSWER));
+	RETERR(dns_rdata_tostruct(&rtkeyrdata, &rtkey, NULL));
+
+	RETERR(find_tkey(qmsg, &tempname, &qtkeyrdata, DNS_SECTION_ADDITIONAL));
+	RETERR(dns_rdata_tostruct(&qtkeyrdata, &qtkey, NULL));
+
+	if (rtkey.error != dns_rcode_noerror ||
+	    rtkey.mode != DNS_TKEYMODE_DELETE || rtkey.mode != qtkey.mode ||
+	    !dns_name_equal(&rtkey.algorithm, &qtkey.algorithm) ||
+	    rmsg->rcode != dns_rcode_noerror)
+	{
+		tkey_log("dns_tkey_processdeleteresponse: tkey mode invalid "
+			 "or error set(3)");
+		result = DNS_R_INVALIDTKEY;
+		dns_rdata_freestruct(&qtkey);
+		dns_rdata_freestruct(&rtkey);
+		goto failure;
+	}
+
+	dns_rdata_freestruct(&qtkey);
+
+	RETERR(dns_tsigkey_find(&tsigkey, tkeyname, &rtkey.algorithm, ring));
+
+	dns_rdata_freestruct(&rtkey);
+
+	/*
+	 * Mark the key as deleted.
+	 */
+	dns_tsigkey_setdeleted(tsigkey);
+	/*
+	 * Release the reference.
+	 */
+	dns_tsigkey_detach(&tsigkey);
+
+failure:
+	return (result);
+}
+
+isc_result_t
+dns_tkey_gssnegotiate(dns_message_t *qmsg, dns_message_t *rmsg,
+		      const dns_name_t *server, dns_gss_ctx_id_t *context,
+		      dns_tsigkey_t **outkey, dns_tsig_keyring_t *ring,
+		      bool win2k, char **err_message) {
+	dns_rdata_t rtkeyrdata = DNS_RDATA_INIT, qtkeyrdata = DNS_RDATA_INIT;
+	dns_name_t *tkeyname;
+	dns_rdata_tkey_t rtkey, qtkey, tkey;
+	isc_buffer_t intoken, outtoken;
+	dst_key_t *dstkey = NULL;
+	isc_result_t result;
+	unsigned char array[TEMP_BUFFER_SZ];
+	bool freertkey = false;
+
+	REQUIRE(qmsg != NULL);
+	REQUIRE(rmsg != NULL);
+	REQUIRE(server != NULL);
+	if (outkey != NULL) {
+		REQUIRE(*outkey == NULL);
+	}
+
+	if (rmsg->rcode != dns_rcode_noerror) {
+		return (ISC_RESULTCLASS_DNSRCODE + rmsg->rcode);
+	}
+
+	RETERR(find_tkey(rmsg, &tkeyname, &rtkeyrdata, DNS_SECTION_ANSWER));
+	RETERR(dns_rdata_tostruct(&rtkeyrdata, &rtkey, NULL));
+	freertkey = true;
+
+	if (win2k) {
+		RETERR(find_tkey(qmsg, &tkeyname, &qtkeyrdata,
+				 DNS_SECTION_ANSWER));
+	} else {
+		RETERR(find_tkey(qmsg, &tkeyname, &qtkeyrdata,
+				 DNS_SECTION_ADDITIONAL));
+	}
+
+	RETERR(dns_rdata_tostruct(&qtkeyrdata, &qtkey, NULL));
+
+	if (rtkey.error != dns_rcode_noerror ||
+	    rtkey.mode != DNS_TKEYMODE_GSSAPI ||
+	    !dns_name_equal(&rtkey.algorithm, &qtkey.algorithm))
+	{
+		tkey_log("dns_tkey_processdhresponse: tkey mode invalid "
+			 "or error set(4)");
+		result = DNS_R_INVALIDTKEY;
+		goto failure;
+	}
+
+	isc_buffer_init(&intoken, rtkey.key, rtkey.keylen);
+	isc_buffer_init(&outtoken, array, sizeof(array));
+
+	result = dst_gssapi_initctx(server, &intoken, &outtoken, context,
+				    ring->mctx, err_message);
+	if (result != DNS_R_CONTINUE && result != ISC_R_SUCCESS) {
+		return (result);
+	}
+
+	if (result == DNS_R_CONTINUE) {
+		dns_fixedname_t fixed;
+
+		dns_fixedname_init(&fixed);
+		dns_name_copynf(tkeyname, dns_fixedname_name(&fixed));
+		tkeyname = dns_fixedname_name(&fixed);
+
+		tkey.common.rdclass = dns_rdataclass_any;
+		tkey.common.rdtype = dns_rdatatype_tkey;
+		ISC_LINK_INIT(&tkey.common, link);
+		tkey.mctx = NULL;
+		dns_name_init(&tkey.algorithm, NULL);
+
+		if (win2k) {
+			dns_name_clone(DNS_TSIG_GSSAPIMS_NAME, &tkey.algorithm);
+		} else {
+			dns_name_clone(DNS_TSIG_GSSAPI_NAME, &tkey.algorithm);
+		}
+
+		tkey.inception = qtkey.inception;
+		tkey.expire = qtkey.expire;
+		tkey.mode = DNS_TKEYMODE_GSSAPI;
+		tkey.error = 0;
+		tkey.key = isc_buffer_base(&outtoken);
+		tkey.keylen = isc_buffer_usedlength(&outtoken);
+		tkey.other = NULL;
+		tkey.otherlen = 0;
+
+		dns_message_reset(qmsg, DNS_MESSAGE_INTENTRENDER);
+		RETERR(buildquery(qmsg, tkeyname, &tkey, win2k));
+		return (DNS_R_CONTINUE);
+	}
+
+	RETERR(dst_key_fromgssapi(dns_rootname, *context, rmsg->mctx, &dstkey,
+				  NULL));
+
+	/*
+	 * XXXSRA This seems confused.  If we got CONTINUE from initctx,
+	 * the GSS negotiation hasn't completed yet, so we can't sign
+	 * anything yet.
+	 */
+
+	RETERR(dns_tsigkey_createfromkey(
+		tkeyname,
+		(win2k ? DNS_TSIG_GSSAPIMS_NAME : DNS_TSIG_GSSAPI_NAME), dstkey,
+		true, NULL, rtkey.inception, rtkey.expire, ring->mctx, ring,
+		outkey));
+	dst_key_free(&dstkey);
+	dns_rdata_freestruct(&rtkey);
+	return (result);
+
+failure:
+	/*
+	 * XXXSRA This probably leaks memory from qtkey.
+	 */
+	if (freertkey) {
+		dns_rdata_freestruct(&rtkey);
+	}
+	if (dstkey != NULL) {
+		dst_key_free(&dstkey);
+	}
+	return (result);
+}