Subversion-Projekte lars-tiefland.php_share

<?php
/*
 * Copyright 2010-2012 Amazon.com, Inc. or its affiliates. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License").
 * You may not use this file except in compliance with the License.
 * A copy of the License is located at
 *
 *  http://aws.amazon.com/apache2.0
 *
 * or in the "license" file accompanying this file. This file is distributed
 * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
 * express or implied. See the License for the specific language governing
 * permissions and limitations under the License.
 */


/*%******************************************************************************************%*/
// CLASS

/**
 * Simplifies the process of signing JSON policy documents.
 *
 * @version 2011.04.25
 * @license See the included NOTICE.md file for more information.
 * @copyright See the included NOTICE.md file for more information.
 * @link http://aws.amazon.com/php/ PHP Developer Center
 */
class CFPolicy
{
        /**
         * Stores the object that contains the authentication credentials.
         */
        public $auth;

        /**
         * Stores the policy object that we're working with.
         */
        public $json_policy;

        /**
         * Constructs a new instance of this class.
         *
         * @param CFRuntime $auth (Required) An instance of any authenticated AWS object that is an instance of <CFRuntime> (e.g. <AmazonEC2>, <AmazonS3>).
         * @param string|array $policy (Required) The associative array representing the S3 policy to use, or a string of JSON content.
         * @return $this A reference to the current instance.
         * @link http://docs.amazonwebservices.com/AmazonS3/2006-03-01/dev/index.html?HTTPPOSTForms.html S3 Policies
         * @link http://docs.amazonwebservices.com/AmazonS3/latest/dev/index.html?AccessPolicyLanguage.html Access Policy Language
         */
        public function __construct($auth, $policy)
        {
                $this->auth = $auth;

                if (is_array($policy)) // We received an associative array...
                {
                        $this->json_policy = json_encode($policy);
                }
                else // We received a valid, parseable JSON string...
                {
                        $this->json_policy = json_encode(json_decode($policy, true));
                }

                return $this;
        }

        /**
         * Alternate approach to constructing a new instance. Supports chaining.
         *
         * @param CFRuntime $auth (Required) An instance of any authenticated AWS object that is an instance of <CFRuntime> (e.g. <AmazonEC2>, <AmazonS3>).
         * @param string|array $policy (Required) The associative array representing the S3 policy to use, or a string of JSON content.
         * @return $this A reference to the current instance.
         */
        public static function init($auth, $policy)
        {
                if (version_compare(PHP_VERSION, '5.3.0', '<'))
                {
                        throw new Exception('PHP 5.3 or newer is required to instantiate a new class with CLASS::init().');
                }

                $self = get_called_class();
                return new $self($auth, $policy);
        }

        /**
         * Get the key from the authenticated instance.
         *
         * @return string The key from the authenticated instance.
         */
        public function get_key()
        {
                return $this->auth->key;
        }

        /**
         * Base64-encodes the JSON string.
         *
         * @return string The Base64-encoded version of the JSON string.
         */
        public function get_policy()
        {
                return base64_encode($this->json_policy);
        }

        /**
         * Gets the JSON string with the whitespace removed.
         *
         * @return string The JSON string without extraneous whitespace.
         */
        public function get_json()
        {
                return $this->json_policy;
        }

        /**
         * Gets the JSON string with the whitespace removed.
         *
         * @return string The Base64-encoded, signed JSON string.
         */
        public function get_policy_signature()
        {
                return base64_encode(hash_hmac('sha1', $this->get_policy(), $this->auth->secret_key));
        }

        /**
         * Decode a policy that was returned from the service.
         *
         * @param string $response (Required) The policy returned by AWS that you want to decode into an object.
         * @return string The Base64-encoded, signed JSON string.
         */
        public static function decode_policy($response)
        {
                return json_decode(urldecode($response), true);
        }
}