pcy_tree.c

开源的ssl算法openssl,版本0.9.8H

/* pcy_tree.c */
/* Written by Dr Stephen N Henson ([e-mail]) 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
 *    [e-mail].
 *
 * 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
 * ([e-mail]).  This product includes software written by Tim
 * Hudson ([e-mail]).
 *
 */

#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);
	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);