/* Written by Dr Stephen N Henson (steve@openssl.org) 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 <openssl/mem.h>
#include <openssl/obj.h>
#include <openssl/thread.h>
#include <openssl/x509.h>
#include <openssl/x509v3.h>

#include "pcy_int.h"
#include "../internal.h"


static int policy_data_cmp(const X509_POLICY_DATA **a,
				const X509_POLICY_DATA **b);
static int policy_cache_set_int(long *out, ASN1_INTEGER *value);

/* Set cache entry according to CertificatePolicies extension.
 * Note: this destroys the passed CERTIFICATEPOLICIES structure.
 */

static int policy_cache_create(X509 *x,
			CERTIFICATEPOLICIES *policies, int crit)
	{
	size_t i;
	int ret = 0;
	X509_POLICY_CACHE *cache = x->policy_cache;
	X509_POLICY_DATA *data = NULL;
	POLICYINFO *policy;
	if (sk_POLICYINFO_num(policies) == 0)
		goto bad_policy;
	cache->data = sk_X509_POLICY_DATA_new(policy_data_cmp);
	if (!cache->data)
		goto bad_policy;
	for (i = 0; i < sk_POLICYINFO_num(policies); i++)
		{
		policy = sk_POLICYINFO_value(policies, i);
		data = policy_data_new(policy, NULL, crit);
		if (!data)
			goto bad_policy;
		/* Duplicate policy OIDs are illegal: reject if matches
		 * found.
		 */
		if (OBJ_obj2nid(data->valid_policy) == NID_any_policy)
			{
			if (cache->anyPolicy)
				{
				ret = -1;
				goto bad_policy;
				}
			cache->anyPolicy = data;
			}
		else if (sk_X509_POLICY_DATA_find(cache->data, NULL, data))
			{
			ret = -1;
			goto bad_policy;
			}
		else if (!sk_X509_POLICY_DATA_push(cache->data, data))
			goto bad_policy;
		data = NULL;
		}
	ret = 1;
	bad_policy:
	if (ret == -1)
		x->ex_flags |= EXFLAG_INVALID_POLICY;
	if (data)
		policy_data_free(data);
	sk_POLICYINFO_pop_free(policies, POLICYINFO_free);
	if (ret <= 0)
		{
		sk_X509_POLICY_DATA_pop_free(cache->data, policy_data_free);
		cache->data = NULL;
		}
	return ret;
	}

	
static int policy_cache_new(X509 *x)
	{
	X509_POLICY_CACHE *cache;
	ASN1_INTEGER *ext_any = NULL;
	POLICY_CONSTRAINTS *ext_pcons = NULL;
	CERTIFICATEPOLICIES *ext_cpols = NULL;
	POLICY_MAPPINGS *ext_pmaps = NULL;
	int i;
	cache = OPENSSL_malloc(sizeof(X509_POLICY_CACHE));
	if (!cache)
		return 0;
	cache->anyPolicy = NULL;
	cache->data = NULL;
	cache->any_skip = -1;
	cache->explicit_skip = -1;
	cache->map_skip = -1;

	x->policy_cache = cache;

	/* Handle requireExplicitPolicy *first*. Need to process this
	 * even if we don't have any policies.
	 */
	ext_pcons = X509_get_ext_d2i(x, NID_policy_constraints, &i, NULL);

	if (!ext_pcons)
		{
		if (i != -1)
			goto bad_cache;
		}
	else
		{
		if (!ext_pcons->requireExplicitPolicy
			&& !ext_pcons->inhibitPolicyMapping)
			goto bad_cache;
		if (!policy_cache_set_int(&cache->explicit_skip,
			ext_pcons->requireExplicitPolicy))
			goto bad_cache;
		if (!policy_cache_set_int(&cache->map_skip,
			ext_pcons->inhibitPolicyMapping))
			goto bad_cache;
		}

	/* Process CertificatePolicies */

	ext_cpols = X509_get_ext_d2i(x, NID_certificate_policies, &i, NULL);
	/* If no CertificatePolicies extension or problem decoding then
	 * there is no point continuing because the valid policies will be
	 * NULL.
	 */
	if (!ext_cpols)
		{
		/* If not absent some problem with extension */
		if (i != -1)
			goto bad_cache;
		return 1;
		}

	i = policy_cache_create(x, ext_cpols, i);

	/* NB: ext_cpols freed by policy_cache_set_policies */

	if (i <= 0)
		return i;

	ext_pmaps = X509_get_ext_d2i(x, NID_policy_mappings, &i, NULL);

	if (!ext_pmaps)
		{
		/* If not absent some problem with extension */
		if (i != -1)
			goto bad_cache;
		}
	else
		{
		i = policy_cache_set_mapping(x, ext_pmaps);
		if (i <= 0)
			goto bad_cache;
		}

	ext_any = X509_get_ext_d2i(x, NID_inhibit_any_policy, &i, NULL);

	if (!ext_any)
		{
		if (i != -1)
			goto bad_cache;
		}
	else if (!policy_cache_set_int(&cache->any_skip, ext_any))
			goto bad_cache;

	if (0)
		{
		bad_cache:
		x->ex_flags |= EXFLAG_INVALID_POLICY;
		}

	if(ext_pcons)
		POLICY_CONSTRAINTS_free(ext_pcons);

	if (ext_any)
		ASN1_INTEGER_free(ext_any);

	return 1;

	
}

void policy_cache_free(X509_POLICY_CACHE *cache)
	{
	if (!cache)
		return;
	if (cache->anyPolicy)
		policy_data_free(cache->anyPolicy);
	if (cache->data)
		sk_X509_POLICY_DATA_pop_free(cache->data, policy_data_free);
	OPENSSL_free(cache);
	}

/* g_x509_policy_cache_lock is used to protect against concurrent calls to
 * |policy_cache_new|. Ideally this would be done with a |CRYPTO_once_t|
 * in the |X509| structure, but |CRYPTO_once_t| isn't public. */
static struct CRYPTO_STATIC_MUTEX g_x509_policy_cache_lock =
    CRYPTO_STATIC_MUTEX_INIT;

const X509_POLICY_CACHE *policy_cache_set(X509 *x)
	{
	X509_POLICY_CACHE *cache;

	CRYPTO_STATIC_MUTEX_lock_read(&g_x509_policy_cache_lock);
	cache = x->policy_cache;
	CRYPTO_STATIC_MUTEX_unlock(&g_x509_policy_cache_lock);

	if (cache != NULL)
		return cache;

	CRYPTO_STATIC_MUTEX_lock_write(&g_x509_policy_cache_lock);
	if (x->policy_cache == NULL)
		policy_cache_new(x);
	cache = x->policy_cache;
	CRYPTO_STATIC_MUTEX_unlock(&g_x509_policy_cache_lock);

	return cache;
	}

X509_POLICY_DATA *policy_cache_find_data(const X509_POLICY_CACHE *cache,
						const ASN1_OBJECT *id)
	{
	size_t idx;
	X509_POLICY_DATA tmp;

	tmp.valid_policy = (ASN1_OBJECT *)id;
	if (!sk_X509_POLICY_DATA_find(cache->data, &idx, &tmp))
		return NULL;
	return sk_X509_POLICY_DATA_value(cache->data, idx);
	}

static int policy_data_cmp(const X509_POLICY_DATA **a,
				const X509_POLICY_DATA **b)
	{
	return OBJ_cmp((*a)->valid_policy, (*b)->valid_policy);
	}

static int policy_cache_set_int(long *out, ASN1_INTEGER *value)
	{
	if (value == NULL)
		return 1;
	if (value->type == V_ASN1_NEG_INTEGER)
		return 0;
	*out = ASN1_INTEGER_get(value);
	return 1;
	}