Adding upstream version 1:9.18.19.upstream/1%9.18.19upstream

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

1 files changed, 1057 insertions, 0 deletions

diff --git a/lib/isccc/cc.c b/lib/isccc/cc.c
new file mode 100644
index 0000000..cbd9bad
--- /dev/null
+++ b/lib/isccc/cc.c
@@ -0,0 +1,1057 @@
+/*
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0 AND 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 https://mozilla.org/MPL/2.0/.
+ *
+ * See the COPYRIGHT file distributed with this work for additional
+ * information regarding copyright ownership.
+ */
+
+/*
+ * Copyright (C) 2001 Nominum, Inc.
+ *
+ * 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 AND NOMINUM 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.
+ */
+
+/*! \file */
+
+#include <errno.h>
+#include <inttypes.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <isc/assertions.h>
+#include <isc/hmac.h>
+#include <isc/print.h>
+#include <isc/result.h>
+#include <isc/safe.h>
+
+#include <isccc/alist.h>
+#include <isccc/base64.h>
+#include <isccc/cc.h>
+#include <isccc/sexpr.h>
+#include <isccc/symtab.h>
+#include <isccc/symtype.h>
+#include <isccc/util.h>
+
+#define MAX_TAGS     256
+#define DUP_LIFETIME 900
+#ifndef ISCCC_MAXDEPTH
+#define ISCCC_MAXDEPTH \
+	10 /* Big enough for rndc which just sends a string each way. */
+#endif
+
+typedef isccc_sexpr_t *sexpr_ptr;
+
+static unsigned char auth_hmd5[] = {
+	0x05, 0x5f, 0x61, 0x75, 0x74, 0x68, /*%< len + _auth */
+	ISCCC_CCMSGTYPE_TABLE,		    /*%< message type */
+	0x00, 0x00, 0x00, 0x20,		    /*%< length == 32 */
+	0x04, 0x68, 0x6d, 0x64, 0x35,	    /*%< len + hmd5 */
+	ISCCC_CCMSGTYPE_BINARYDATA,	    /*%< message type */
+	0x00, 0x00, 0x00, 0x16,		    /*%< length == 22 */
+	/*
+	 * The base64 encoding of one of our HMAC-MD5 signatures is
+	 * 22 bytes.
+	 */
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
+};
+
+#define HMD5_OFFSET 21 /*%< 21 = 6 + 1 + 4 + 5 + 1 + 4 */
+#define HMD5_LENGTH 22
+
+static unsigned char auth_hsha[] = {
+	0x05, 0x5f, 0x61, 0x75, 0x74, 0x68, /*%< len + _auth */
+	ISCCC_CCMSGTYPE_TABLE,		    /*%< message type */
+	0x00, 0x00, 0x00, 0x63,		    /*%< length == 99 */
+	0x04, 0x68, 0x73, 0x68, 0x61,	    /*%< len + hsha */
+	ISCCC_CCMSGTYPE_BINARYDATA,	    /*%< message type */
+	0x00, 0x00, 0x00, 0x59,		    /*%< length == 89 */
+	0x00,				    /*%< algorithm */
+	/*
+	 * The base64 encoding of one of our HMAC-SHA* signatures is
+	 * 88 bytes.
+	 */
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	0x00, 0x00, 0x00, 0x00
+};
+
+#define HSHA_OFFSET 22 /*%< 21 = 6 + 1 + 4 + 5 + 1 + 4 + 1 */
+#define HSHA_LENGTH 88
+
+static isc_result_t
+table_towire(isccc_sexpr_t *alist, isc_buffer_t **buffer);
+
+static isc_result_t
+list_towire(isccc_sexpr_t *alist, isc_buffer_t **buffer);
+
+static isc_result_t
+value_towire(isccc_sexpr_t *elt, isc_buffer_t **buffer) {
+	unsigned int len;
+	isccc_region_t *vr;
+	isc_result_t result;
+
+	if (isccc_sexpr_binaryp(elt)) {
+		vr = isccc_sexpr_tobinary(elt);
+		len = REGION_SIZE(*vr);
+		result = isc_buffer_reserve(buffer, 1 + 4);
+		if (result != ISC_R_SUCCESS) {
+			return (ISC_R_NOSPACE);
+		}
+		isc_buffer_putuint8(*buffer, ISCCC_CCMSGTYPE_BINARYDATA);
+		isc_buffer_putuint32(*buffer, len);
+
+		result = isc_buffer_reserve(buffer, len);
+		if (result != ISC_R_SUCCESS) {
+			return (ISC_R_NOSPACE);
+		}
+		isc_buffer_putmem(*buffer, vr->rstart, len);
+	} else if (isccc_alist_alistp(elt)) {
+		unsigned int used;
+		isc_buffer_t b;
+
+		result = isc_buffer_reserve(buffer, 1 + 4);
+		if (result != ISC_R_SUCCESS) {
+			return (ISC_R_NOSPACE);
+		}
+		isc_buffer_putuint8(*buffer, ISCCC_CCMSGTYPE_TABLE);
+		/*
+		 * Emit a placeholder length.
+		 */
+		used = (*buffer)->used;
+		isc_buffer_putuint32(*buffer, 0);
+
+		/*
+		 * Emit the table.
+		 */
+		result = table_towire(elt, buffer);
+		if (result != ISC_R_SUCCESS) {
+			return (result);
+		}
+
+		len = (*buffer)->used - used;
+		/*
+		 * 'len' is 4 bytes too big, since it counts
+		 * the placeholder length too.	Adjust and
+		 * emit.
+		 */
+		INSIST(len >= 4U);
+		len -= 4;
+
+		isc_buffer_init(&b, (unsigned char *)(*buffer)->base + used, 4);
+		isc_buffer_putuint32(&b, len);
+	} else if (isccc_sexpr_listp(elt)) {
+		unsigned int used;
+		isc_buffer_t b;
+
+		result = isc_buffer_reserve(buffer, 1 + 4);
+		if (result != ISC_R_SUCCESS) {
+			return (ISC_R_NOSPACE);
+		}
+		isc_buffer_putuint8(*buffer, ISCCC_CCMSGTYPE_LIST);
+		/*
+		 * Emit a placeholder length.
+		 */
+		used = (*buffer)->used;
+		isc_buffer_putuint32(*buffer, 0);
+
+		/*
+		 * Emit the list.
+		 */
+		result = list_towire(elt, buffer);
+		if (result != ISC_R_SUCCESS) {
+			return (result);
+		}
+
+		len = (*buffer)->used - used;
+		/*
+		 * 'len' is 4 bytes too big, since it counts
+		 * the placeholder length too.	Adjust and
+		 * emit.
+		 */
+		INSIST(len >= 4U);
+		len -= 4;
+
+		isc_buffer_init(&b, (unsigned char *)(*buffer)->base + used, 4);
+		isc_buffer_putuint32(&b, len);
+	}
+
+	return (ISC_R_SUCCESS);
+}
+
+static isc_result_t
+table_towire(isccc_sexpr_t *alist, isc_buffer_t **buffer) {
+	isccc_sexpr_t *kv, *elt, *k, *v;
+	char *ks;
+	isc_result_t result;
+	unsigned int len;
+
+	for (elt = isccc_alist_first(alist); elt != NULL;
+	     elt = ISCCC_SEXPR_CDR(elt))
+	{
+		kv = ISCCC_SEXPR_CAR(elt);
+		k = ISCCC_SEXPR_CAR(kv);
+		ks = isccc_sexpr_tostring(k);
+		v = ISCCC_SEXPR_CDR(kv);
+		len = (unsigned int)strlen(ks);
+		INSIST(len <= 255U);
+		/*
+		 * Emit the key name.
+		 */
+		result = isc_buffer_reserve(buffer, 1 + len);
+		if (result != ISC_R_SUCCESS) {
+			return (ISC_R_NOSPACE);
+		}
+		isc_buffer_putuint8(*buffer, (uint8_t)len);
+		isc_buffer_putmem(*buffer, (const unsigned char *)ks, len);
+		/*
+		 * Emit the value.
+		 */
+		result = value_towire(v, buffer);
+		if (result != ISC_R_SUCCESS) {
+			return (result);
+		}
+	}
+
+	return (ISC_R_SUCCESS);
+}
+
+static isc_result_t
+list_towire(isccc_sexpr_t *list, isc_buffer_t **buffer) {
+	isc_result_t result;
+
+	while (list != NULL) {
+		result = value_towire(ISCCC_SEXPR_CAR(list), buffer);
+		if (result != ISC_R_SUCCESS) {
+			return (result);
+		}
+		list = ISCCC_SEXPR_CDR(list);
+	}
+
+	return (ISC_R_SUCCESS);
+}
+
+static isc_result_t
+sign(unsigned char *data, unsigned int length, unsigned char *hmac,
+     uint32_t algorithm, isccc_region_t *secret) {
+	const isc_md_type_t *md_type;
+	isc_result_t result;
+	isccc_region_t source, target;
+	unsigned char digest[ISC_MAX_MD_SIZE];
+	unsigned int digestlen = sizeof(digest);
+	unsigned char digestb64[HSHA_LENGTH + 4];
+
+	source.rstart = digest;
+
+	switch (algorithm) {
+	case ISCCC_ALG_HMACMD5:
+		md_type = ISC_MD_MD5;
+		break;
+	case ISCCC_ALG_HMACSHA1:
+		md_type = ISC_MD_SHA1;
+		break;
+	case ISCCC_ALG_HMACSHA224:
+		md_type = ISC_MD_SHA224;
+		break;
+	case ISCCC_ALG_HMACSHA256:
+		md_type = ISC_MD_SHA256;
+		break;
+	case ISCCC_ALG_HMACSHA384:
+		md_type = ISC_MD_SHA384;
+		break;
+	case ISCCC_ALG_HMACSHA512:
+		md_type = ISC_MD_SHA512;
+		break;
+	default:
+		return (ISC_R_NOTIMPLEMENTED);
+	}
+
+	result = isc_hmac(md_type, secret->rstart, REGION_SIZE(*secret), data,
+			  length, digest, &digestlen);
+	if (result != ISC_R_SUCCESS) {
+		return (result);
+	}
+	source.rend = digest + digestlen;
+
+	memset(digestb64, 0, sizeof(digestb64));
+	target.rstart = digestb64;
+	target.rend = digestb64 + sizeof(digestb64);
+	result = isccc_base64_encode(&source, 64, "", &target);
+	if (result != ISC_R_SUCCESS) {
+		return (result);
+	}
+	if (algorithm == ISCCC_ALG_HMACMD5) {
+		PUT_MEM(digestb64, HMD5_LENGTH, hmac);
+	} else {
+		PUT_MEM(digestb64, HSHA_LENGTH, hmac);
+	}
+	return (ISC_R_SUCCESS);
+}
+
+isc_result_t
+isccc_cc_towire(isccc_sexpr_t *alist, isc_buffer_t **buffer, uint32_t algorithm,
+		isccc_region_t *secret) {
+	unsigned int hmac_base, signed_base;
+	isc_result_t result;
+
+	result = isc_buffer_reserve(buffer,
+				    4 + ((algorithm == ISCCC_ALG_HMACMD5)
+						 ? sizeof(auth_hmd5)
+						 : sizeof(auth_hsha)));
+	if (result != ISC_R_SUCCESS) {
+		return (ISC_R_NOSPACE);
+	}
+
+	/*
+	 * Emit protocol version.
+	 */
+	isc_buffer_putuint32(*buffer, 1);
+
+	if (secret != NULL) {
+		/*
+		 * Emit _auth section with zeroed HMAC signature.
+		 * We'll replace the zeros with the real signature once
+		 * we know what it is.
+		 */
+		if (algorithm == ISCCC_ALG_HMACMD5) {
+			hmac_base = (*buffer)->used + HMD5_OFFSET;
+			isc_buffer_putmem(*buffer, auth_hmd5,
+					  sizeof(auth_hmd5));
+		} else {
+			unsigned char *hmac_alg;
+
+			hmac_base = (*buffer)->used + HSHA_OFFSET;
+			hmac_alg = (unsigned char *)isc_buffer_used(*buffer) +
+				   HSHA_OFFSET - 1;
+			isc_buffer_putmem(*buffer, auth_hsha,
+					  sizeof(auth_hsha));
+			*hmac_alg = algorithm;
+		}
+	} else {
+		hmac_base = 0;
+	}
+	signed_base = (*buffer)->used;
+	/*
+	 * Delete any existing _auth section so that we don't try
+	 * to encode it.
+	 */
+	isccc_alist_delete(alist, "_auth");
+	/*
+	 * Emit the message.
+	 */
+	result = table_towire(alist, buffer);
+	if (result != ISC_R_SUCCESS) {
+		return (result);
+	}
+	if (secret != NULL) {
+		return (sign((unsigned char *)(*buffer)->base + signed_base,
+			     (*buffer)->used - signed_base,
+			     (unsigned char *)(*buffer)->base + hmac_base,
+			     algorithm, secret));
+	}
+	return (ISC_R_SUCCESS);
+}
+
+static isc_result_t
+verify(isccc_sexpr_t *alist, unsigned char *data, unsigned int length,
+       uint32_t algorithm, isccc_region_t *secret) {
+	const isc_md_type_t *md_type;
+	isccc_region_t source;
+	isccc_region_t target;
+	isc_result_t result;
+	isccc_sexpr_t *_auth, *hmac;
+	unsigned char digest[ISC_MAX_MD_SIZE];
+	unsigned int digestlen = sizeof(digest);
+	unsigned char digestb64[HSHA_LENGTH * 4];
+
+	/*
+	 * Extract digest.
+	 */
+	_auth = isccc_alist_lookup(alist, "_auth");
+	if (!isccc_alist_alistp(_auth)) {
+		return (ISC_R_FAILURE);
+	}
+	if (algorithm == ISCCC_ALG_HMACMD5) {
+		hmac = isccc_alist_lookup(_auth, "hmd5");
+	} else {
+		hmac = isccc_alist_lookup(_auth, "hsha");
+	}
+	if (!isccc_sexpr_binaryp(hmac)) {
+		return (ISC_R_FAILURE);
+	}
+	/*
+	 * Compute digest.
+	 */
+	source.rstart = digest;
+
+	switch (algorithm) {
+	case ISCCC_ALG_HMACMD5:
+		md_type = ISC_MD_MD5;
+		break;
+	case ISCCC_ALG_HMACSHA1:
+		md_type = ISC_MD_SHA1;
+		break;
+	case ISCCC_ALG_HMACSHA224:
+		md_type = ISC_MD_SHA224;
+		break;
+	case ISCCC_ALG_HMACSHA256:
+		md_type = ISC_MD_SHA256;
+		break;
+	case ISCCC_ALG_HMACSHA384:
+		md_type = ISC_MD_SHA384;
+		break;
+	case ISCCC_ALG_HMACSHA512:
+		md_type = ISC_MD_SHA512;
+		break;
+	default:
+		return (ISC_R_NOTIMPLEMENTED);
+	}
+
+	result = isc_hmac(md_type, secret->rstart, REGION_SIZE(*secret), data,
+			  length, digest, &digestlen);
+	if (result != ISC_R_SUCCESS) {
+		return (result);
+	}
+	source.rend = digest + digestlen;
+
+	target.rstart = digestb64;
+	target.rend = digestb64 + sizeof(digestb64);
+	memset(digestb64, 0, sizeof(digestb64));
+	result = isccc_base64_encode(&source, 64, "", &target);
+	if (result != ISC_R_SUCCESS) {
+		return (result);
+	}
+
+	/*
+	 * Verify.
+	 */
+	if (algorithm == ISCCC_ALG_HMACMD5) {
+		isccc_region_t *region;
+		unsigned char *value;
+
+		region = isccc_sexpr_tobinary(hmac);
+		if ((region->rend - region->rstart) != HMD5_LENGTH) {
+			return (ISCCC_R_BADAUTH);
+		}
+		value = region->rstart;
+		if (!isc_safe_memequal(value, digestb64, HMD5_LENGTH)) {
+			return (ISCCC_R_BADAUTH);
+		}
+	} else {
+		isccc_region_t *region;
+		unsigned char *value;
+		uint32_t valalg;
+
+		region = isccc_sexpr_tobinary(hmac);
+
+		/*
+		 * Note: with non-MD5 algorithms, there's an extra octet
+		 * to identify which algorithm is in use.
+		 */
+		if ((region->rend - region->rstart) != HSHA_LENGTH + 1) {
+			return (ISCCC_R_BADAUTH);
+		}
+		value = region->rstart;
+		GET8(valalg, value);
+		if ((valalg != algorithm) ||
+		    !isc_safe_memequal(value, digestb64, HSHA_LENGTH))
+		{
+			return (ISCCC_R_BADAUTH);
+		}
+	}
+
+	return (ISC_R_SUCCESS);
+}
+
+static isc_result_t
+table_fromwire(isccc_region_t *source, isccc_region_t *secret,
+	       uint32_t algorithm, unsigned int depth, isccc_sexpr_t **alistp);
+
+static isc_result_t
+list_fromwire(isccc_region_t *source, unsigned int depth,
+	      isccc_sexpr_t **listp);
+
+static isc_result_t
+value_fromwire(isccc_region_t *source, unsigned int depth,
+	       isccc_sexpr_t **valuep) {
+	unsigned int msgtype;
+	uint32_t len;
+	isccc_sexpr_t *value;
+	isccc_region_t active;
+	isc_result_t result;
+
+	if (depth > ISCCC_MAXDEPTH) {
+		return (ISCCC_R_MAXDEPTH);
+	}
+
+	if (REGION_SIZE(*source) < 1 + 4) {
+		return (ISC_R_UNEXPECTEDEND);
+	}
+	GET8(msgtype, source->rstart);
+	GET32(len, source->rstart);
+	if (REGION_SIZE(*source) < len) {
+		return (ISC_R_UNEXPECTEDEND);
+	}
+	active.rstart = source->rstart;
+	active.rend = active.rstart + len;
+	source->rstart = active.rend;
+	if (msgtype == ISCCC_CCMSGTYPE_BINARYDATA) {
+		value = isccc_sexpr_frombinary(&active);
+		if (value != NULL) {
+			*valuep = value;
+			result = ISC_R_SUCCESS;
+		} else {
+			result = ISC_R_NOMEMORY;
+		}
+	} else if (msgtype == ISCCC_CCMSGTYPE_TABLE) {
+		result = table_fromwire(&active, NULL, 0, depth + 1, valuep);
+	} else if (msgtype == ISCCC_CCMSGTYPE_LIST) {
+		result = list_fromwire(&active, depth + 1, valuep);
+	} else {
+		result = ISCCC_R_SYNTAX;
+	}
+
+	return (result);
+}
+
+static isc_result_t
+table_fromwire(isccc_region_t *source, isccc_region_t *secret,
+	       uint32_t algorithm, unsigned int depth, isccc_sexpr_t **alistp) {
+	char key[256];
+	uint32_t len;
+	isc_result_t result;
+	isccc_sexpr_t *alist, *value;
+	bool first_tag;
+	unsigned char *checksum_rstart;
+
+	REQUIRE(alistp != NULL && *alistp == NULL);
+
+	if (depth > ISCCC_MAXDEPTH) {
+		return (ISCCC_R_MAXDEPTH);
+	}
+
+	checksum_rstart = NULL;
+	first_tag = true;
+	alist = isccc_alist_create();
+	if (alist == NULL) {
+		return (ISC_R_NOMEMORY);
+	}
+
+	while (!REGION_EMPTY(*source)) {
+		GET8(len, source->rstart);
+		if (REGION_SIZE(*source) < len) {
+			result = ISC_R_UNEXPECTEDEND;
+			goto bad;
+		}
+		GET_MEM(key, len, source->rstart);
+		key[len] = '\0'; /* Ensure NUL termination. */
+		value = NULL;
+		result = value_fromwire(source, depth + 1, &value);
+		if (result != ISC_R_SUCCESS) {
+			goto bad;
+		}
+		if (isccc_alist_define(alist, key, value) == NULL) {
+			result = ISC_R_NOMEMORY;
+			goto bad;
+		}
+		if (first_tag && secret != NULL && strcmp(key, "_auth") == 0) {
+			checksum_rstart = source->rstart;
+		}
+		first_tag = false;
+	}
+
+	if (secret != NULL) {
+		if (checksum_rstart != NULL) {
+			result = verify(
+				alist, checksum_rstart,
+				(unsigned int)(source->rend - checksum_rstart),
+				algorithm, secret);
+		} else {
+			result = ISCCC_R_BADAUTH;
+		}
+	} else {
+		result = ISC_R_SUCCESS;
+	}
+
+bad:
+	if (result == ISC_R_SUCCESS) {
+		*alistp = alist;
+	} else {
+		isccc_sexpr_free(&alist);
+	}
+
+	return (result);
+}
+
+static isc_result_t
+list_fromwire(isccc_region_t *source, unsigned int depth,
+	      isccc_sexpr_t **listp) {
+	isccc_sexpr_t *list, *value;
+	isc_result_t result;
+
+	if (depth > ISCCC_MAXDEPTH) {
+		return (ISCCC_R_MAXDEPTH);
+	}
+
+	list = NULL;
+	while (!REGION_EMPTY(*source)) {
+		value = NULL;
+		result = value_fromwire(source, depth + 1, &value);
+		if (result != ISC_R_SUCCESS) {
+			isccc_sexpr_free(&list);
+			return (result);
+		}
+		if (isccc_sexpr_addtolist(&list, value) == NULL) {
+			isccc_sexpr_free(&value);
+			isccc_sexpr_free(&list);
+			return (ISC_R_NOMEMORY);
+		}
+	}
+
+	*listp = list;
+
+	return (ISC_R_SUCCESS);
+}
+
+isc_result_t
+isccc_cc_fromwire(isccc_region_t *source, isccc_sexpr_t **alistp,
+		  uint32_t algorithm, isccc_region_t *secret) {
+	unsigned int size;
+	uint32_t version;
+
+	size = REGION_SIZE(*source);
+	if (size < 4) {
+		return (ISC_R_UNEXPECTEDEND);
+	}
+	GET32(version, source->rstart);
+	if (version != 1) {
+		return (ISCCC_R_UNKNOWNVERSION);
+	}
+
+	return (table_fromwire(source, secret, algorithm, 0, alistp));
+}
+
+static isc_result_t
+createmessage(uint32_t version, const char *from, const char *to,
+	      uint32_t serial, isccc_time_t now, isccc_time_t expires,
+	      isccc_sexpr_t **alistp, bool want_expires) {
+	isccc_sexpr_t *alist, *_ctrl, *_data;
+	isc_result_t result;
+
+	REQUIRE(alistp != NULL && *alistp == NULL);
+
+	if (version != 1) {
+		return (ISCCC_R_UNKNOWNVERSION);
+	}
+
+	alist = isccc_alist_create();
+	if (alist == NULL) {
+		return (ISC_R_NOMEMORY);
+	}
+
+	result = ISC_R_NOMEMORY;
+
+	_ctrl = isccc_alist_create();
+	if (_ctrl == NULL) {
+		goto bad;
+	}
+	if (isccc_alist_define(alist, "_ctrl", _ctrl) == NULL) {
+		isccc_sexpr_free(&_ctrl);
+		goto bad;
+	}
+
+	_data = isccc_alist_create();
+	if (_data == NULL) {
+		goto bad;
+	}
+	if (isccc_alist_define(alist, "_data", _data) == NULL) {
+		isccc_sexpr_free(&_data);
+		goto bad;
+	}
+
+	if (isccc_cc_defineuint32(_ctrl, "_ser", serial) == NULL ||
+	    isccc_cc_defineuint32(_ctrl, "_tim", now) == NULL ||
+	    (want_expires &&
+	     isccc_cc_defineuint32(_ctrl, "_exp", expires) == NULL))
+	{
+		goto bad;
+	}
+	if (from != NULL && isccc_cc_definestring(_ctrl, "_frm", from) == NULL)
+	{
+		goto bad;
+	}
+	if (to != NULL && isccc_cc_definestring(_ctrl, "_to", to) == NULL) {
+		goto bad;
+	}
+
+	*alistp = alist;
+
+	return (ISC_R_SUCCESS);
+
+bad:
+	isccc_sexpr_free(&alist);
+
+	return (result);
+}
+
+isc_result_t
+isccc_cc_createmessage(uint32_t version, const char *from, const char *to,
+		       uint32_t serial, isccc_time_t now, isccc_time_t expires,
+		       isccc_sexpr_t **alistp) {
+	return (createmessage(version, from, to, serial, now, expires, alistp,
+			      true));
+}
+
+isc_result_t
+isccc_cc_createack(isccc_sexpr_t *message, bool ok, isccc_sexpr_t **ackp) {
+	char *_frm, *_to;
+	uint32_t serial;
+	isccc_sexpr_t *ack, *_ctrl;
+	isc_result_t result;
+	isccc_time_t t;
+
+	REQUIRE(ackp != NULL && *ackp == NULL);
+
+	_ctrl = isccc_alist_lookup(message, "_ctrl");
+	if (!isccc_alist_alistp(_ctrl) ||
+	    isccc_cc_lookupuint32(_ctrl, "_ser", &serial) != ISC_R_SUCCESS ||
+	    isccc_cc_lookupuint32(_ctrl, "_tim", &t) != ISC_R_SUCCESS)
+	{
+		return (ISC_R_FAILURE);
+	}
+	/*
+	 * _frm and _to are optional.
+	 */
+	_frm = NULL;
+	(void)isccc_cc_lookupstring(_ctrl, "_frm", &_frm);
+	_to = NULL;
+	(void)isccc_cc_lookupstring(_ctrl, "_to", &_to);
+	/*
+	 * Create the ack.
+	 */
+	ack = NULL;
+	result = createmessage(1, _to, _frm, serial, t, 0, &ack, false);
+	if (result != ISC_R_SUCCESS) {
+		return (result);
+	}
+
+	_ctrl = isccc_alist_lookup(ack, "_ctrl");
+	if (_ctrl == NULL) {
+		result = ISC_R_FAILURE;
+		goto bad;
+	}
+	if (isccc_cc_definestring(ack, "_ack", (ok) ? "1" : "0") == NULL) {
+		result = ISC_R_NOMEMORY;
+		goto bad;
+	}
+
+	*ackp = ack;
+
+	return (ISC_R_SUCCESS);
+
+bad:
+	isccc_sexpr_free(&ack);
+
+	return (result);
+}
+
+bool
+isccc_cc_isack(isccc_sexpr_t *message) {
+	isccc_sexpr_t *_ctrl;
+
+	_ctrl = isccc_alist_lookup(message, "_ctrl");
+	if (!isccc_alist_alistp(_ctrl)) {
+		return (false);
+	}
+	if (isccc_cc_lookupstring(_ctrl, "_ack", NULL) == ISC_R_SUCCESS) {
+		return (true);
+	}
+	return (false);
+}
+
+bool
+isccc_cc_isreply(isccc_sexpr_t *message) {
+	isccc_sexpr_t *_ctrl;
+
+	_ctrl = isccc_alist_lookup(message, "_ctrl");
+	if (!isccc_alist_alistp(_ctrl)) {
+		return (false);
+	}
+	if (isccc_cc_lookupstring(_ctrl, "_rpl", NULL) == ISC_R_SUCCESS) {
+		return (true);
+	}
+	return (false);
+}
+
+isc_result_t
+isccc_cc_createresponse(isccc_sexpr_t *message, isccc_time_t now,
+			isccc_time_t expires, isccc_sexpr_t **alistp) {
+	char *_frm, *_to, *type = NULL;
+	uint32_t serial;
+	isccc_sexpr_t *alist, *_ctrl, *_data;
+	isc_result_t result;
+
+	REQUIRE(alistp != NULL && *alistp == NULL);
+
+	_ctrl = isccc_alist_lookup(message, "_ctrl");
+	_data = isccc_alist_lookup(message, "_data");
+	if (!isccc_alist_alistp(_ctrl) || !isccc_alist_alistp(_data) ||
+	    isccc_cc_lookupuint32(_ctrl, "_ser", &serial) != ISC_R_SUCCESS ||
+	    isccc_cc_lookupstring(_data, "type", &type) != ISC_R_SUCCESS)
+	{
+		return (ISC_R_FAILURE);
+	}
+	/*
+	 * _frm and _to are optional.
+	 */
+	_frm = NULL;
+	(void)isccc_cc_lookupstring(_ctrl, "_frm", &_frm);
+	_to = NULL;
+	(void)isccc_cc_lookupstring(_ctrl, "_to", &_to);
+	/*
+	 * Create the response.
+	 */
+	alist = NULL;
+	result = isccc_cc_createmessage(1, _to, _frm, serial, now, expires,
+					&alist);
+	if (result != ISC_R_SUCCESS) {
+		return (result);
+	}
+
+	_ctrl = isccc_alist_lookup(alist, "_ctrl");
+	if (_ctrl == NULL) {
+		result = ISC_R_FAILURE;
+		goto bad;
+	}
+
+	_data = isccc_alist_lookup(alist, "_data");
+	if (_data == NULL) {
+		result = ISC_R_FAILURE;
+		goto bad;
+	}
+
+	if (isccc_cc_definestring(_ctrl, "_rpl", "1") == NULL ||
+	    isccc_cc_definestring(_data, "type", type) == NULL)
+	{
+		result = ISC_R_NOMEMORY;
+		goto bad;
+	}
+
+	*alistp = alist;
+
+	return (ISC_R_SUCCESS);
+
+bad:
+	isccc_sexpr_free(&alist);
+	return (result);
+}
+
+isccc_sexpr_t *
+isccc_cc_definestring(isccc_sexpr_t *alist, const char *key, const char *str) {
+	size_t len;
+	isccc_region_t r;
+
+	len = strlen(str);
+	DE_CONST(str, r.rstart);
+	r.rend = r.rstart + len;
+
+	return (isccc_alist_definebinary(alist, key, &r));
+}
+
+isccc_sexpr_t *
+isccc_cc_defineuint32(isccc_sexpr_t *alist, const char *key, uint32_t i) {
+	char b[100];
+	size_t len;
+	isccc_region_t r;
+
+	snprintf(b, sizeof(b), "%u", i);
+	len = strlen(b);
+	r.rstart = (unsigned char *)b;
+	r.rend = (unsigned char *)b + len;
+
+	return (isccc_alist_definebinary(alist, key, &r));
+}
+
+isc_result_t
+isccc_cc_lookupstring(isccc_sexpr_t *alist, const char *key, char **strp) {
+	isccc_sexpr_t *kv, *v;
+
+	REQUIRE(strp == NULL || *strp == NULL);
+
+	kv = isccc_alist_assq(alist, key);
+	if (kv != NULL) {
+		v = ISCCC_SEXPR_CDR(kv);
+		if (isccc_sexpr_binaryp(v)) {
+			if (strp != NULL) {
+				*strp = isccc_sexpr_tostring(v);
+			}
+			return (ISC_R_SUCCESS);
+		} else {
+			return (ISC_R_EXISTS);
+		}
+	}
+
+	return (ISC_R_NOTFOUND);
+}
+
+isc_result_t
+isccc_cc_lookupuint32(isccc_sexpr_t *alist, const char *key, uint32_t *uintp) {
+	isccc_sexpr_t *kv, *v;
+
+	kv = isccc_alist_assq(alist, key);
+	if (kv != NULL) {
+		v = ISCCC_SEXPR_CDR(kv);
+		if (isccc_sexpr_binaryp(v)) {
+			if (uintp != NULL) {
+				*uintp = (uint32_t)strtoul(
+					isccc_sexpr_tostring(v), NULL, 10);
+			}
+			return (ISC_R_SUCCESS);
+		} else {
+			return (ISC_R_EXISTS);
+		}
+	}
+
+	return (ISC_R_NOTFOUND);
+}
+
+static void
+symtab_undefine(char *key, unsigned int type, isccc_symvalue_t value,
+		void *arg) {
+	UNUSED(type);
+	UNUSED(value);
+	UNUSED(arg);
+
+	free(key);
+}
+
+static bool
+symtab_clean(char *key, unsigned int type, isccc_symvalue_t value, void *arg) {
+	isccc_time_t *now;
+
+	UNUSED(key);
+	UNUSED(type);
+
+	now = arg;
+
+	if (*now < value.as_uinteger) {
+		return (false);
+	}
+	if ((*now - value.as_uinteger) < DUP_LIFETIME) {
+		return (false);
+	}
+	return (true);
+}
+
+isc_result_t
+isccc_cc_createsymtab(isccc_symtab_t **symtabp) {
+	return (isccc_symtab_create(11897, symtab_undefine, NULL, false,
+				    symtabp));
+}
+
+void
+isccc_cc_cleansymtab(isccc_symtab_t *symtab, isccc_time_t now) {
+	isccc_symtab_foreach(symtab, symtab_clean, &now);
+}
+
+static bool
+has_whitespace(const char *str) {
+	char c;
+
+	if (str == NULL) {
+		return (false);
+	}
+	while ((c = *str++) != '\0') {
+		if (c == ' ' || c == '\t' || c == '\n') {
+			return (true);
+		}
+	}
+	return (false);
+}
+
+isc_result_t
+isccc_cc_checkdup(isccc_symtab_t *symtab, isccc_sexpr_t *message,
+		  isccc_time_t now) {
+	const char *_frm;
+	const char *_to;
+	char *_ser = NULL, *_tim = NULL, *tmp;
+	isc_result_t result;
+	char *key;
+	size_t len;
+	isccc_symvalue_t value;
+	isccc_sexpr_t *_ctrl;
+
+	_ctrl = isccc_alist_lookup(message, "_ctrl");
+	if (!isccc_alist_alistp(_ctrl) ||
+	    isccc_cc_lookupstring(_ctrl, "_ser", &_ser) != ISC_R_SUCCESS ||
+	    isccc_cc_lookupstring(_ctrl, "_tim", &_tim) != ISC_R_SUCCESS)
+	{
+		return (ISC_R_FAILURE);
+	}
+
+	INSIST(_ser != NULL);
+	INSIST(_tim != NULL);
+
+	/*
+	 * _frm and _to are optional.
+	 */
+	tmp = NULL;
+	if (isccc_cc_lookupstring(_ctrl, "_frm", &tmp) != ISC_R_SUCCESS) {
+		_frm = "";
+	} else {
+		_frm = tmp;
+	}
+	tmp = NULL;
+	if (isccc_cc_lookupstring(_ctrl, "_to", &tmp) != ISC_R_SUCCESS) {
+		_to = "";
+	} else {
+		_to = tmp;
+	}
+	/*
+	 * Ensure there is no newline in any of the strings.  This is so
+	 * we can write them to a file later.
+	 */
+	if (has_whitespace(_frm) || has_whitespace(_to) ||
+	    has_whitespace(_ser) || has_whitespace(_tim))
+	{
+		return (ISC_R_FAILURE);
+	}
+	len = strlen(_frm) + strlen(_to) + strlen(_ser) + strlen(_tim) + 4;
+	key = malloc(len);
+	if (key == NULL) {
+		return (ISC_R_NOMEMORY);
+	}
+	snprintf(key, len, "%s;%s;%s;%s", _frm, _to, _ser, _tim);
+	value.as_uinteger = now;
+	result = isccc_symtab_define(symtab, key, ISCCC_SYMTYPE_CCDUP, value,
+				     isccc_symexists_reject);
+	if (result != ISC_R_SUCCESS) {
+		free(key);
+		return (result);
+	}
+
+	return (ISC_R_SUCCESS);
+}