pcy_tree.c

开源的ssl算法openssl,版本0.9.8H

			(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);
	}


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.
 */

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;

	}