/*
 * Copyright (C) 2004-2006  Internet Systems Consortium, Inc. ("ISC")
 * Copyright (C) 1999-2002  Internet Software Consortium.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND 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.
 */

/* $ISC: aclconf.c,v 1.2.2.6 2006/03/02 00:37:22 marka Exp $ */

#include <config.h>

#include <isc/mem.h>
#include <isc/string.h>		/* Required for HP/UX (and others?) */
#include <isc/util.h>

#include <isccfg/namedconf.h>
#include <isccfg/aclconf.h>

#include <dns/acl.h>
#include <dns/fixedname.h>
#include <dns/log.h>

#define LOOP_MAGIC ISC_MAGIC('L','O','O','P') 

void
cfg_aclconfctx_init(cfg_aclconfctx_t *ctx) {
	ISC_LIST_INIT(ctx->named_acl_cache);
}

void
cfg_aclconfctx_destroy(cfg_aclconfctx_t *ctx) {
     	dns_acl_t *dacl, *next;
	for (dacl = ISC_LIST_HEAD(ctx->named_acl_cache);
	     dacl != NULL;
	     dacl = next)
	{
		next = ISC_LIST_NEXT(dacl, nextincache);
		dns_acl_detach(&dacl);
	}
}

/*
 * Find the definition of the named acl whose name is "name".
 */
static isc_result_t
get_acl_def(const cfg_obj_t *cctx, const char *name, const cfg_obj_t **ret) {
	isc_result_t result;
	const cfg_obj_t *acls = NULL;
	const cfg_listelt_t *elt;
	
	result = cfg_map_get(cctx, "acl", &acls);
	if (result != ISC_R_SUCCESS)
		return (result);
	for (elt = cfg_list_first(acls);
	     elt != NULL;
	     elt = cfg_list_next(elt)) {
		const cfg_obj_t *acl = cfg_listelt_value(elt);
		const char *aclname = cfg_obj_asstring(cfg_tuple_get(acl, "name"));
		if (strcasecmp(aclname, name) == 0) {
			*ret = cfg_tuple_get(acl, "value");
			return (ISC_R_SUCCESS);
		}
	}
	return (ISC_R_NOTFOUND);
}

static isc_result_t
convert_named_acl(const cfg_obj_t *nameobj, const cfg_obj_t *cctx,
		  isc_log_t *lctx, cfg_aclconfctx_t *ctx,
		  isc_mem_t *mctx, dns_acl_t **target)
{
	isc_result_t result;
	const cfg_obj_t *cacl = NULL;
	dns_acl_t *dacl;
	dns_acl_t loop;
	const char *aclname = cfg_obj_asstring(nameobj);

	/* Look for an already-converted version. */
	for (dacl = ISC_LIST_HEAD(ctx->named_acl_cache);
	     dacl != NULL;
	     dacl = ISC_LIST_NEXT(dacl, nextincache))
	{
		if (strcasecmp(aclname, dacl->name) == 0) {
			if (ISC_MAGIC_VALID(dacl, LOOP_MAGIC)) {
				cfg_obj_log(nameobj, lctx, ISC_LOG_ERROR,
					    "acl loop detected: %s", aclname);
				return (ISC_R_FAILURE);
			}
			dns_acl_attach(dacl, target);
			return (ISC_R_SUCCESS);
		}
	}
	/* Not yet converted.  Convert now. */
	result = get_acl_def(cctx, aclname, &cacl);
	if (result != ISC_R_SUCCESS) {
		cfg_obj_log(nameobj, lctx, ISC_LOG_WARNING,
			    "undefined ACL '%s'", aclname);
		return (result);
	}
	/*
	 * Add a loop detection element.
	 */
	memset(&loop, 0, sizeof(loop));
	ISC_LINK_INIT(&loop, nextincache);
	DE_CONST(aclname, loop.name);
	loop.magic = LOOP_MAGIC;
	ISC_LIST_APPEND(ctx->named_acl_cache, &loop, nextincache);
	result = cfg_acl_fromconfig(cacl, cctx, lctx, ctx, mctx, &dacl);
	ISC_LIST_UNLINK(ctx->named_acl_cache, &loop, nextincache);
	loop.magic = 0;
	loop.name = NULL;
	if (result != ISC_R_SUCCESS)
		return (result);
	dacl->name = isc_mem_strdup(dacl->mctx, aclname);
	if (dacl->name == NULL)
		return (ISC_R_NOMEMORY);
	ISC_LIST_APPEND(ctx->named_acl_cache, dacl, nextincache);
	dns_acl_attach(dacl, target);
	return (ISC_R_SUCCESS);
}

static isc_result_t
convert_keyname(const cfg_obj_t *keyobj, isc_log_t *lctx, isc_mem_t *mctx,
		dns_name_t *dnsname)
{
	isc_result_t result;
	isc_buffer_t buf;
	dns_fixedname_t fixname;
	unsigned int keylen;
	const char *txtname = cfg_obj_asstring(keyobj);

	keylen = strlen(txtname);
	isc_buffer_init(&buf, txtname, keylen);
	isc_buffer_add(&buf, keylen);
	dns_fixedname_init(&fixname);
	result = dns_name_fromtext(dns_fixedname_name(&fixname), &buf,
				   dns_rootname, ISC_FALSE, NULL);
	if (result != ISC_R_SUCCESS) {
		cfg_obj_log(keyobj, lctx, ISC_LOG_WARNING,
			    "key name '%s' is not a valid domain name",
			    txtname);
		return (result);
	}
	return (dns_name_dup(dns_fixedname_name(&fixname), mctx, dnsname));
}

isc_result_t
cfg_acl_fromconfig(const cfg_obj_t *caml,
		   const cfg_obj_t *cctx,
	 	   isc_log_t *lctx,
		   cfg_aclconfctx_t *ctx,
		   isc_mem_t *mctx,
		   dns_acl_t **target)
{
	isc_result_t result;
	unsigned int count;
	dns_acl_t *dacl = NULL;
	dns_aclelement_t *de;
	const cfg_listelt_t *elt;

	REQUIRE(target != NULL && *target == NULL);

	count = 0;
	for (elt = cfg_list_first(caml);
	     elt != NULL;
	     elt = cfg_list_next(elt))
		count++;

	result = dns_acl_create(mctx, count, &dacl);
	if (result != ISC_R_SUCCESS)
		return (result);

	de = dacl->elements;
	for (elt = cfg_list_first(caml);
	     elt != NULL;
	     elt = cfg_list_next(elt))
	{
		const cfg_obj_t *ce = cfg_listelt_value(elt);
		if (cfg_obj_istuple(ce)) {
			/* This must be a negated element. */
			ce = cfg_tuple_get(ce, "value");
			de->negative = ISC_TRUE;
		} else {
			de->negative = ISC_FALSE;
		}

		if (cfg_obj_isnetprefix(ce)) {
			/* Network prefix */
			de->type = dns_aclelementtype_ipprefix;

			cfg_obj_asnetprefix(ce,
					    &de->u.ip_prefix.address,
					    &de->u.ip_prefix.prefixlen);
		} else if (cfg_obj_istype(ce, &cfg_type_keyref)) {
			/* Key name */
			de->type = dns_aclelementtype_keyname;
			dns_name_init(&de->u.keyname, NULL);
			result = convert_keyname(ce, lctx, mctx,
						 &de->u.keyname);
			if (result != ISC_R_SUCCESS)
				goto cleanup;
		} else if (cfg_obj_islist(ce)) {
			/* Nested ACL */
			de->type = dns_aclelementtype_nestedacl;
			result = cfg_acl_fromconfig(ce, cctx, lctx, ctx,
						    mctx, &de->u.nestedacl);
			if (result != ISC_R_SUCCESS)
				goto cleanup;
		} else if (cfg_obj_isstring(ce)) {
			/* ACL name */
			const char *name = cfg_obj_asstring(ce);
			if (strcasecmp(name, "localhost") == 0) {
				de->type = dns_aclelementtype_localhost;
			} else if (strcasecmp(name, "localnets") == 0) {
				de->type = dns_aclelementtype_localnets;
			}  else if (strcasecmp(name, "any") == 0) {
				de->type = dns_aclelementtype_any;
			}  else if (strcasecmp(name, "none") == 0) {
				de->type = dns_aclelementtype_any;
				de->negative = ISC_TF(! de->negative);
			} else {
				de->type = dns_aclelementtype_nestedacl;
				result = convert_named_acl(ce, cctx, lctx,
							   ctx, mctx,
							   &de->u.nestedacl);
				if (result != ISC_R_SUCCESS)
					goto cleanup;
			}
		} else {
			cfg_obj_log(ce, lctx, ISC_LOG_WARNING,
				    "address match list contains "
				    "unsupported element type");
			result = ISC_R_FAILURE;
			goto cleanup;
		}
		de++;
		dacl->length++;
	}

	*target = dacl;
	return (ISC_R_SUCCESS);

 cleanup:
	dns_acl_detach(&dacl);
	return (result);
}