/* pcy_tree.c */

 /* Written by Dr Stephen N Henson (shenson@bigfoot.com) for the OpenSSL

  * project 2004.

  */

 /* ====================================================================

  * Copyright (c) 2004 The OpenSSL Project.  All rights reserved.

  *

  * Redistribution and use in source and binary forms, with or without

  * modification, are permitted provided that the following conditions

  * are met:

  *

  * 1. Redistributions of source code must retain the above copyright

  *    notice, this list of conditions and the following disclaimer. 

  *

  * 2. Redistributions in binary form must reproduce the above copyright

  *    notice, this list of conditions and the following disclaimer in

  *    the documentation and/or other materials provided with the

  *    distribution.

  *

  * 3. All advertising materials mentioning features or use of this

  *    software must display the following acknowledgment:

  *    "This product includes software developed by the OpenSSL Project

  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"

  *

  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to

  *    endorse or promote products derived from this software without

  *    prior written permission. For written permission, please contact

  *    licensing@OpenSSL.org.

  *

  * 5. Products derived from this software may not be called "OpenSSL"

  *    nor may "OpenSSL" appear in their names without prior written

  *    permission of the OpenSSL Project.

  *

  * 6. Redistributions of any form whatsoever must retain the following

  *    acknowledgment:

  *    "This product includes software developed by the OpenSSL Project

  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"

  *

  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY

  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR

  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT

  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;

  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,

  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED

  * OF THE POSSIBILITY OF SUCH DAMAGE.

  * ====================================================================

  *

  * This product includes cryptographic software written by Eric Young

  * (eay@cryptsoft.com).  This product includes software written by Tim

  * Hudson (tjh@cryptsoft.com).

  *

  */

 #include "cryptlib.h"

 #include <openssl/x509.h>

 #include <openssl/x509v3.h>

 #include "pcy_int.h"

 /* Initialize policy tree. Return values:

  *  0 Some internal error occured.

  * -1 Inconsistent or invalid extensions in certificates.

  *  1 Tree initialized OK.

  *  2 Policy tree is empty.

  *  5 Tree OK and requireExplicitPolicy true.

  *  6 Tree empty and requireExplicitPolicy true.

  */

 static int tree_init(X509_POLICY_TREE **ptree, STACK_OF(X509) *certs,

 			unsigned int flags)

 	{

 	X509_POLICY_TREE *tree;

 	X509_POLICY_LEVEL *level;

 	const X509_POLICY_CACHE *cache;

 	X509_POLICY_DATA *data = NULL;

 	X509 *x;

 	int ret = 1;

 	int i, n;

 	int explicit_policy;

 	int any_skip;

 	int map_skip;

 	*ptree = NULL;

 	n = sk_X509_num(certs);

 	/* Disable policy mapping for now... */

 	flags |= X509_V_FLAG_INHIBIT_MAP;

 	if (flags & X509_V_FLAG_EXPLICIT_POLICY)

 		explicit_policy = 0;

 	else

 		explicit_policy = n + 1;

 	if (flags & X509_V_FLAG_INHIBIT_ANY)

 		any_skip = 0;

 	else

 		any_skip = n + 1;

 	if (flags & X509_V_FLAG_INHIBIT_MAP)

 		map_skip = 0;

 	else

 		map_skip = n + 1;

 	/* Can't do anything with just a trust anchor */

 	if (n == 1)

 		return 1;

 	/* First setup policy cache in all certificates apart from the

 	 * trust anchor. Note any bad cache results on the way. Also can

 	 * calculate explicit_policy value at this point.

 	 */

 	for (i = n - 2; i >= 0; i--)

 		{

 		x = sk_X509_value(certs, i);

 		X509_check_purpose(x, -1, -1);

 		cache = policy_cache_set(x);

 		/* If cache NULL something bad happened: return immediately */

 		if (cache == NULL)

 			return 0;

 		/* If inconsistent extensions keep a note of it but continue */

 		if (x->ex_flags & EXFLAG_INVALID_POLICY)

 			ret = -1;

 		/* Otherwise if we have no data (hence no CertificatePolicies)

 		 * and haven't already set an inconsistent code note it.

 		 */

 		else if ((ret == 1) && !cache->data)

 			ret = 2;

 		if (explicit_policy > 0)

 			{

 			explicit_policy--;

 			if (!(x->ex_flags & EXFLAG_SS)

 				&& (cache->explicit_skip != -1)

 				&& (cache->explicit_skip < explicit_policy))

 				explicit_policy = cache->explicit_skip;

 			}

 		}

 	if (ret != 1)

 		{

 		if (ret == 2 && !explicit_policy)

 			return 6;

 		return ret;

 		}

 	/* If we get this far initialize the tree */

 	tree = OPENSSL_malloc(sizeof(X509_POLICY_TREE));

 	if (!tree)

 		return 0;

 	tree->flags = 0;

 	tree->levels = OPENSSL_malloc(sizeof(X509_POLICY_LEVEL) * n);

 #ifdef SYMBIAN	

 	if (!tree->levels)

 		return 0;

 #endif

 	tree->nlevel = 0;

 	tree->extra_data = NULL;

 	tree->auth_policies = NULL;

 	tree->user_policies = NULL;

 	if (!tree)

 		{

 		OPENSSL_free(tree);

 		return 0;

 		}

 	memset(tree->levels, 0, n * sizeof(X509_POLICY_LEVEL));

 	tree->nlevel = n;

 	level = tree->levels;

 	/* Root data: initialize to anyPolicy */

 	data = policy_data_new(NULL, OBJ_nid2obj(NID_any_policy), 0);

 	if (!data || !level_add_node(level, data, NULL, tree))

 		goto bad_tree;

 	for (i = n - 2; i >= 0; i--)

 		{

 		level++;

 		x = sk_X509_value(certs, i);

 		cache = policy_cache_set(x);

 		CRYPTO_add(&x->references, 1, CRYPTO_LOCK_X509);

 		level->cert = x;

 		if (!cache->anyPolicy)

 				level->flags |= X509_V_FLAG_INHIBIT_ANY;

 		/* Determine inhibit any and inhibit map flags */

 		if (any_skip == 0)

 			{

 			/* Any matching allowed if certificate is self

 			 * issued and not the last in the chain.

 			 */

 			if (!(x->ex_flags & EXFLAG_SS) || (i == 0))

 				level->flags |= X509_V_FLAG_INHIBIT_ANY;

 			}

 		else

 			{

 			any_skip--;

 			if ((cache->any_skip > 0)

 				&& (cache->any_skip < any_skip))

 				any_skip = cache->any_skip;

 			}

 		if (map_skip == 0)

 			level->flags |= X509_V_FLAG_INHIBIT_MAP;

 		else

 			{

 			map_skip--;

 			if ((cache->map_skip > 0)

 				&& (cache->map_skip < map_skip))

 				map_skip = cache->map_skip;

 			}

 		}

 	*ptree = tree;

 	if (explicit_policy)

 		return 1;

 	else

 		return 5;

 	bad_tree:

 	X509_policy_tree_free(tree);

 	return 0;

 	}

 /* This corresponds to RFC3280 XXXX XXXXX:

  * link any data from CertificatePolicies onto matching parent

  * or anyPolicy if no match.

  */

 static int tree_link_nodes(X509_POLICY_LEVEL *curr,

 				const X509_POLICY_CACHE *cache)

 	{

 	int i;

 	X509_POLICY_LEVEL *last;

 	X509_POLICY_DATA *data;

 	X509_POLICY_NODE *parent;

 	last = curr - 1;

 	for (i = 0; i < sk_X509_POLICY_DATA_num(cache->data); i++)

 		{

 		data = sk_X509_POLICY_DATA_value(cache->data, i);

 		/* If a node is mapped any it doesn't have a corresponding

 		 * CertificatePolicies entry. 

 		 * However such an identical node would be created

 		 * if anyPolicy matching is enabled because there would be

 		 * no match with the parent valid_policy_set. So we create

 		 * link because then it will have the mapping flags

 		 * right and we can prune it later.

 		 */

 		if ((data->flags & POLICY_DATA_FLAG_MAPPED_ANY)

 			&& !(curr->flags & X509_V_FLAG_INHIBIT_ANY))

 			continue;

 		/* Look for matching node in parent */

 		parent = level_find_node(last, data->valid_policy);

 		/* If no match link to anyPolicy */

 		if (!parent)

 			parent = last->anyPolicy;

 		if (parent && !level_add_node(curr, data, parent, NULL))

 				return 0;

 		}

 	return 1;

 	}

 /* This corresponds to RFC3280 XXXX XXXXX:

  * Create new data for any unmatched policies in the parent and link

  * to anyPolicy.

  */

 static int tree_link_any(X509_POLICY_LEVEL *curr,

 			const X509_POLICY_CACHE *cache,

 			X509_POLICY_TREE *tree)

 	{

 	int i;

 	X509_POLICY_DATA *data;

 	X509_POLICY_NODE *node;

 	X509_POLICY_LEVEL *last;

 	last = curr - 1;

 	for (i = 0; i < sk_X509_POLICY_NODE_num(last->nodes); i++)

 		{

 		node = sk_X509_POLICY_NODE_value(last->nodes, i);

 		/* Skip any node with any children: we only want unmathced

 		 * nodes.

 		 *

 		 * Note: need something better for policy mapping

 		 * because each node may have multiple children 

 		 */

 		if (node->nchild)

 			continue;

 		/* Create a new node with qualifiers from anyPolicy and

 		 * id from unmatched node.

 		 */

 		data = policy_data_new(NULL, node->data->valid_policy, 

 						node_critical(node));

 		if (data == NULL)

 			return 0;

 		data->qualifier_set = curr->anyPolicy->data->qualifier_set;

 		data->flags |= POLICY_DATA_FLAG_SHARED_QUALIFIERS;

 		if (!level_add_node(curr, data, node, tree))

 			{

 			policy_data_free(data);

 			return 0;

 			}

 		}

 	/* Finally add link to anyPolicy */

 	if (last->anyPolicy)

 		{

 		if (!level_add_node(curr, cache->anyPolicy,

 						last->anyPolicy, NULL))

 			return 0;

 		}

 	return 1;

 	}

 /* Prune the tree: delete any child mapped child data on the current level

  * then proceed up the tree deleting any data with no children. If we ever

  * have no data on a level we can halt because the tree will be empty.

  */

 static int tree_prune(X509_POLICY_TREE *tree, X509_POLICY_LEVEL *curr)

 	{

 	X509_POLICY_NODE *node;

 	int i;

 	for (i = sk_X509_POLICY_NODE_num(curr->nodes) - 1; i >= 0; i--)

 		{

 		node = sk_X509_POLICY_NODE_value(curr->nodes, i);

 		/* Delete any mapped data: see RFC3280 XXXX */

 		if (node->data->flags & POLICY_DATA_FLAG_MAP_MASK)

 			{

 			node->parent->nchild--;

 			OPENSSL_free(node);

 			(void)sk_X509_POLICY_NODE_delete(curr->nodes, i);

 			}

 		}

 	for(;;)	{

 		--curr;

 		for (i = sk_X509_POLICY_NODE_num(curr->nodes) - 1; i >= 0; i--)

 			{

 			node = sk_X509_POLICY_NODE_value(curr->nodes, i);

 			if (node->nchild == 0)

 				{

 				node->parent->nchild--;

 				OPENSSL_free(node);

 				(void)sk_X509_POLICY_NODE_delete(curr->nodes, i);

 				}

 			}

 		if (curr->anyPolicy && !curr->anyPolicy->nchild)

 			{

 			if (curr->anyPolicy->parent)

 				curr->anyPolicy->parent->nchild--;

 			OPENSSL_free(curr->anyPolicy);

 			curr->anyPolicy = NULL;

 			}

 		if (curr == tree->levels)

 			{

 			/* If we zapped anyPolicy at top then tree is empty */

 			if (!curr->anyPolicy)

 					return 2;

 			return 1;

 			}

 		}

 	return 1;

 	}

 static int tree_add_auth_node(STACK_OF(X509_POLICY_NODE) **pnodes,

 						 X509_POLICY_NODE *pcy)

 	{

 	if (!*pnodes)

 		{

 		*pnodes = policy_node_cmp_new();

 		if (!*pnodes)

 			return 0;

 		}

 	else if (sk_X509_POLICY_NODE_find(*pnodes, pcy) != -1)

 		return 1;

 	if (!sk_X509_POLICY_NODE_push(*pnodes, pcy))

 		return 0;

 	return 1;

 	}

 /* Calculate the authority set based on policy tree.

  * The 'pnodes' parameter is used as a store for the set of policy nodes

  * used to calculate the user set. If the authority set is not anyPolicy

  * then pnodes will just point to the authority set. If however the authority

  * set is anyPolicy then the set of valid policies (other than anyPolicy)

  * is store in pnodes. The return value of '2' is used in this case to indicate

  * that pnodes should be freed.

  */

 static int tree_calculate_authority_set(X509_POLICY_TREE *tree,

 					STACK_OF(X509_POLICY_NODE) **pnodes)

 	{

 	X509_POLICY_LEVEL *curr;

 	X509_POLICY_NODE *node, *anyptr;

 	STACK_OF(X509_POLICY_NODE) **addnodes;

 	int i, j;

 	curr = tree->levels + tree->nlevel - 1;

 	/* If last level contains anyPolicy set is anyPolicy */

 	if (curr->anyPolicy)

 		{

 		if (!tree_add_auth_node(&tree->auth_policies, curr->anyPolicy))

 			return 0;

 		addnodes = pnodes;

 		}

 	else

 		/* Add policies to authority set */

 		addnodes = &tree->auth_policies;

 	curr = tree->levels;

 	for (i = 1; i < tree->nlevel; i++)

 		{

 		/* If no anyPolicy node on this this level it can't

 		 * appear on lower levels so end search.

 		 */

 		if (!(anyptr = curr->anyPolicy))

 			break;

 		curr++;

 		for (j = 0; j < sk_X509_POLICY_NODE_num(curr->nodes); j++)

 			{

 			node = sk_X509_POLICY_NODE_value(curr->nodes, j);

 			if ((node->parent == anyptr)

 				&& !tree_add_auth_node(addnodes, node))

 					return 0;

 			}

 		}

 	if (addnodes == pnodes)

 		return 2;

 	*pnodes = tree->auth_policies;

 	return 1;

 	}

 static int tree_calculate_user_set(X509_POLICY_TREE *tree,

 				STACK_OF(ASN1_OBJECT) *policy_oids,

 				STACK_OF(X509_POLICY_NODE) *auth_nodes)

 	{

 	int i;

 	X509_POLICY_NODE *node;

 	ASN1_OBJECT *oid;

 	X509_POLICY_NODE *anyPolicy;

 	X509_POLICY_DATA *extra;

 	/* Check if anyPolicy present in authority constrained policy set:

 	 * this will happen if it is a leaf node.

 	 */

 	if (sk_ASN1_OBJECT_num(policy_oids) <= 0)

 		return 1;

 	anyPolicy = tree->levels[tree->nlevel - 1].anyPolicy;

 	for (i = 0; i < sk_ASN1_OBJECT_num(policy_oids); i++)

 		{

 		oid = sk_ASN1_OBJECT_value(policy_oids, i);

 		if (OBJ_obj2nid(oid) == NID_any_policy)

 			{

 			tree->flags |= POLICY_FLAG_ANY_POLICY;

 			return 1;

 			}

 		}

 	for (i = 0; i < sk_ASN1_OBJECT_num(policy_oids); i++)

 		{

 		oid = sk_ASN1_OBJECT_value(policy_oids, i);

 		node = tree_find_sk(auth_nodes, oid);

 		if (!node)

 			{

 			if (!anyPolicy)

 				continue;

 			/* Create a new node with policy ID from user set

 			 * and qualifiers from anyPolicy.

 			 */

 			extra = policy_data_new(NULL, oid,

 						node_critical(anyPolicy));

 			if (!extra)

 				return 0;

 			extra->qualifier_set = anyPolicy->data->qualifier_set;

 			extra->flags = POLICY_DATA_FLAG_SHARED_QUALIFIERS

 						| POLICY_DATA_FLAG_EXTRA_NODE;

 			node = level_add_node(NULL, extra, anyPolicy->parent,

 						tree);

 			}

 		if (!tree->user_policies)

 			{

 			tree->user_policies = sk_X509_POLICY_NODE_new_null();

 			if (!tree->user_policies)

 				return 1;

 			}

 		if (!sk_X509_POLICY_NODE_push(tree->user_policies, node))

 			return 0;

 		}

 	return 1;

 	}

 static int tree_evaluate(X509_POLICY_TREE *tree)

 	{

 	int ret, i;

 	X509_POLICY_LEVEL *curr = tree->levels + 1;

 	const X509_POLICY_CACHE *cache;

 	for(i = 1; i < tree->nlevel; i++, curr++)

 		{

 		cache = policy_cache_set(curr->cert);

 		if (!tree_link_nodes(curr, cache))

 			return 0;

 		if (!(curr->flags & X509_V_FLAG_INHIBIT_ANY)

 			&& !tree_link_any(curr, cache, tree))

 			return 0;

 		ret = tree_prune(tree, curr);

 		if (ret != 1)

 			return ret;

 		}

 	return 1;

 	}

 static void exnode_free(X509_POLICY_NODE *node)

 	{

 	if (node->data && (node->data->flags & POLICY_DATA_FLAG_EXTRA_NODE))

 		OPENSSL_free(node);

 	}

 EXPORT_C void X509_policy_tree_free(X509_POLICY_TREE *tree)

 	{

 	X509_POLICY_LEVEL *curr;

 	int i;

 	if (!tree)

 		return;

 	sk_X509_POLICY_NODE_free(tree->auth_policies);

 	sk_X509_POLICY_NODE_pop_free(tree->user_policies, exnode_free);

 	for(i = 0, curr = tree->levels; i < tree->nlevel; i++, curr++)

 		{

 		if (curr->cert)

 			X509_free(curr->cert);

 		if (curr->nodes)

 			sk_X509_POLICY_NODE_pop_free(curr->nodes,

 						policy_node_free);

 		if (curr->anyPolicy)

 			policy_node_free(curr->anyPolicy);

 		}

 	if (tree->extra_data)

 		sk_X509_POLICY_DATA_pop_free(tree->extra_data,

 						policy_data_free);

 	OPENSSL_free(tree->levels);

 	OPENSSL_free(tree);

 	}

 /* Application policy checking function.

  * Return codes:

  *  0 	Internal Error.

  *  1   Successful.

  * -1   One or more certificates contain invalid or inconsistent extensions

  * -2	User constrained policy set empty and requireExplicit true.

  */

 EXPORT_C int X509_policy_check(X509_POLICY_TREE **ptree, int *pexplicit_policy,

 			STACK_OF(X509) *certs,

 			STACK_OF(ASN1_OBJECT) *policy_oids,

 			unsigned int flags)

 	{

 	int ret;

 	X509_POLICY_TREE *tree = NULL;

 	STACK_OF(X509_POLICY_NODE) *nodes, *auth_nodes = NULL;

 	*ptree = NULL;

 	*pexplicit_policy = 0;

 	ret = tree_init(&tree, certs, flags);

 	switch (ret)

 		{

 		/* Tree empty requireExplicit False: OK */

 		case 2:

 		return 1;

 		/* Some internal error */

 		case 0:

 		return 0;

 		/* Tree empty requireExplicit True: Error */

 		case 6:

 		*pexplicit_policy = 1;

 		return -2;

 		/* Tree OK requireExplicit True: OK and continue */

 		case 5:

 		*pexplicit_policy = 1;

 		break;

 		/* Tree OK: continue */

 		case 1:

 		if (!tree)

 			/*

 			 * tree_init() returns success and a null tree

 			 * if it's just looking at a trust anchor.

 			 * I'm not sure that returning success here is

 			 * correct, but I'm sure that reporting this

 			 * as an internal error which our caller

 			 * interprets as a malloc failure is wrong.

 			 */

 			return 1;

 		break;

 		}

 	if (!tree) goto error;

 	ret = tree_evaluate(tree);

 	if (ret <= 0)

 		goto error;

 	/* Return value 2 means tree empty */

 	if (ret == 2)

 		{

 		X509_policy_tree_free(tree);

 		if (*pexplicit_policy)

 			return -2;

 		else

 			return 1;

 		}

 	/* Tree is not empty: continue */

 	ret = tree_calculate_authority_set(tree, &auth_nodes);

 	if (!ret)

 		goto error;

 	if (!tree_calculate_user_set(tree, policy_oids, auth_nodes))

 		goto error;

 	if (ret == 2)

 		sk_X509_POLICY_NODE_free(auth_nodes);

 	if (tree)

 		*ptree = tree;

 	if (*pexplicit_policy)

 		{

 		nodes = X509_policy_tree_get0_user_policies(tree);

 		if (sk_X509_POLICY_NODE_num(nodes) <= 0)

 			return -2;

 		}

 	return 1;

 	error:

 	X509_policy_tree_free(tree);

 	return 0;

 	}