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<?php
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/**
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* Copyright 2014 Freemius, Inc.
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*
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* Licensed under the GPL v2 (the "License"); you may
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* not use this file except in compliance with the License. You may obtain
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* a copy of the License at
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*
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* http://choosealicense.com/licenses/gpl-v2/
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
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* License for the specific language governing permissions and limitations
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* under the License.
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*/
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require_once( dirname( __FILE__ ) . '/FreemiusBase.php' );
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define( 'FS_SDK__USER_AGENT', 'fs-php-' . Freemius_Api_Base::VERSION );
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if ( ! defined( 'FS_SDK__SIMULATE_NO_CURL' ) ) {
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define( 'FS_SDK__SIMULATE_NO_CURL', false );
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}
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if ( ! defined( 'FS_SDK__SIMULATE_NO_API_CONNECTIVITY_CLOUDFLARE' ) ) {
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define( 'FS_SDK__SIMULATE_NO_API_CONNECTIVITY_CLOUDFLARE', false );
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}
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if ( ! defined( 'FS_SDK__SIMULATE_NO_API_CONNECTIVITY_SQUID_ACL' ) ) {
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define( 'FS_SDK__SIMULATE_NO_API_CONNECTIVITY_SQUID_ACL', false );
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}
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define( 'FS_SDK__HAS_CURL', ! FS_SDK__SIMULATE_NO_CURL && function_exists( 'curl_version' ) );
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if ( ! FS_SDK__HAS_CURL ) {
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$curl_version = array( 'version' => '7.0.0' );
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} else {
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$curl_version = curl_version();
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}
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define( 'FS_API__PROTOCOL', version_compare( $curl_version['version'], '7.37', '>=' ) ? 'https' : 'http' );
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if ( ! defined( 'FS_API__ADDRESS' ) ) {
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define( 'FS_API__ADDRESS', '://api.freemius.com' );
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}
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if ( ! defined( 'FS_API__SANDBOX_ADDRESS' ) ) {
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define( 'FS_API__SANDBOX_ADDRESS', '://sandbox-api.freemius.com' );
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}
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class Freemius_Api extends Freemius_Api_Base {
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/**
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* Default options for curl.
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*/
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public static $CURL_OPTS = array(
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CURLOPT_CONNECTTIMEOUT => 10,
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CURLOPT_RETURNTRANSFER => true,
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CURLOPT_TIMEOUT => 60,
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CURLOPT_USERAGENT => FS_SDK__USER_AGENT,
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);
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/**
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* @param string $pScope 'app', 'developer', 'user' or 'install'.
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* @param number $pID Element's id.
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* @param string $pPublic Public key.
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* @param string|bool $pSecret Element's secret key.
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* @param bool $pSandbox Whether or not to run API in sandbox mode.
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*/
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public function __construct( $pScope, $pID, $pPublic, $pSecret = false, $pSandbox = false ) {
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// If secret key not provided, use public key encryption.
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if ( is_bool( $pSecret ) ) {
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$pSecret = $pPublic;
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}
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parent::Init( $pScope, $pID, $pPublic, $pSecret, $pSandbox );
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}
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public function GetUrl( $pCanonizedPath = '' ) {
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$address = ( $this->_sandbox ? FS_API__SANDBOX_ADDRESS : FS_API__ADDRESS );
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if ( ':' === $address[0] ) {
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$address = self::$_protocol . $address;
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}
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return $address . $pCanonizedPath;
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}
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/**
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* @var int Clock diff in seconds between current server to API server.
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*/
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private static $_clock_diff = 0;
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/**
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* Set clock diff for all API calls.
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*
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* @since 1.0.3
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*
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* @param $pSeconds
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*/
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public static function SetClockDiff( $pSeconds ) {
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self::$_clock_diff = $pSeconds;
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}
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/**
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* @var string http or https
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*/
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private static $_protocol = FS_API__PROTOCOL;
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/**
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* Set API connection protocol.
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*
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* @since 1.0.4
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*/
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public static function SetHttp() {
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self::$_protocol = 'http';
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}
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/**
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* @since 1.0.4
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*
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* @return bool
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*/
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public static function IsHttps() {
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return ( 'https' === self::$_protocol );
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}
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/**
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* Sign request with the following HTTP headers:
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* Content-MD5: MD5(HTTP Request body)
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* Date: Current date (i.e Sat, 14 Feb 2015 20:24:46 +0000)
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* Authorization: FS {scope_entity_id}:{scope_entity_public_key}:base64encode(sha256(string_to_sign,
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* {scope_entity_secret_key}))
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*
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* @param string $pResourceUrl
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* @param array $opts
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*/
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protected function SignRequest( $pResourceUrl, &$opts ) {
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$eol = "\n";
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$content_md5 = '';
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$now = ( time() - self::$_clock_diff );
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$date = date( 'r', $now );
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$content_type = '';
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if ( isset( $opts[ CURLOPT_POST ] ) && 0 < $opts[ CURLOPT_POST ] ) {
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$content_md5 = md5( $opts[ CURLOPT_POSTFIELDS ] );
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$opts[ CURLOPT_HTTPHEADER ][] = 'Content-MD5: ' . $content_md5;
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$content_type = 'application/json';
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}
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$opts[ CURLOPT_HTTPHEADER ][] = 'Date: ' . $date;
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$string_to_sign = implode( $eol, array(
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$opts[ CURLOPT_CUSTOMREQUEST ],
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$content_md5,
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$content_type,
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$date,
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$pResourceUrl
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) );
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// If secret and public keys are identical, it means that
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// the signature uses public key hash encoding.
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$auth_type = ( $this->_secret !== $this->_public ) ? 'FS' : 'FSP';
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// Add authorization header.
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$opts[ CURLOPT_HTTPHEADER ][] = 'Authorization: ' .
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$auth_type . ' ' .
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$this->_id . ':' .
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$this->_public . ':' .
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self::Base64UrlEncode(
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hash_hmac( 'sha256', $string_to_sign, $this->_secret )
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);
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}
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/**
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* Get API request URL signed via query string.
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*
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* @param string $pPath
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*
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* @throws Freemius_Exception
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*
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* @return string
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*/
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function GetSignedUrl( $pPath ) {
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$resource = explode( '?', $this->CanonizePath( $pPath ) );
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$pResourceUrl = $resource[0];
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$eol = "\n";
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$content_md5 = '';
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$content_type = '';
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$now = ( time() - self::$_clock_diff );
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$date = date( 'r', $now );
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$string_to_sign = implode( $eol, array(
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'GET',
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$content_md5,
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$content_type,
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$date,
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$pResourceUrl
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199
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) );
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201
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// If secret and public keys are identical, it means that
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202
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// the signature uses public key hash encoding.
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203
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$auth_type = ( $this->_secret !== $this->_public ) ? 'FS' : 'FSP';
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204
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205
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return $this->GetUrl(
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$pResourceUrl . '?' .
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( 1 < count( $resource ) && ! empty( $resource[1] ) ? $resource[1] . '&' : '' ) .
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208
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http_build_query( array(
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209
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'auth_date' => $date,
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'authorization' => $auth_type . ' ' . $this->_id . ':' .
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$this->_public . ':' .
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212
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self::Base64UrlEncode( hash_hmac(
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213
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'sha256', $string_to_sign, $this->_secret
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214
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) )
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215
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) ) );
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216
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}
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217
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218
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/**
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219
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* Makes an HTTP request. This method can be overridden by subclasses if
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220
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* developers want to do fancier things or use something other than curl to
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* make the request.
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*
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* @param string $pCanonizedPath The URL to make the request to
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* @param string $pMethod HTTP method
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225
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* @param array $params The parameters to use for the POST body
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226
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* @param null|resource $ch Initialized curl handle
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*
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228
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* @return object[]|object|null
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229
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*
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230
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* @throws Freemius_Exception
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231
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*/
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232
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public function MakeRequest( $pCanonizedPath, $pMethod = 'GET', $params = array(), $ch = null ) {
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233
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if ( !FS_SDK__HAS_CURL ) {
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234
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$this->ThrowNoCurlException();
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235
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}
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236
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237
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// Connectivity errors simulation.
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238
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if ( FS_SDK__SIMULATE_NO_API_CONNECTIVITY_CLOUDFLARE ) {
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239
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$this->ThrowCloudFlareDDoSException();
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240
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} else if ( FS_SDK__SIMULATE_NO_API_CONNECTIVITY_SQUID_ACL ) {
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241
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$this->ThrowSquidAclException();
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242
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}
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243
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244
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if ( ! $ch ) {
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245
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$ch = curl_init();
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246
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}
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247
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248
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$opts = self::$CURL_OPTS;
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249
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250
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if ( ! isset( $opts[ CURLOPT_HTTPHEADER ] ) || ! is_array( $opts[ CURLOPT_HTTPHEADER ] ) ) {
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251
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$opts[ CURLOPT_HTTPHEADER ] = array();
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252
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}
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253
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254
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if ( 'POST' === $pMethod || 'PUT' === $pMethod ) {
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255
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if ( is_array( $params ) && 0 < count( $params ) ) {
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256
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$opts[ CURLOPT_HTTPHEADER ][] = 'Content-Type: application/json';
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257
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$opts[ CURLOPT_POST ] = count( $params );
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258
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$opts[ CURLOPT_POSTFIELDS ] = json_encode( $params );
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259
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}
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260
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261
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$opts[ CURLOPT_RETURNTRANSFER ] = true;
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262
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}
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263
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264
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$opts[ CURLOPT_URL ] = $this->GetUrl( $pCanonizedPath );
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265
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$opts[ CURLOPT_CUSTOMREQUEST ] = $pMethod;
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266
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267
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$resource = explode( '?', $pCanonizedPath );
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268
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269
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// Only sign request if not ping.json connectivity test.
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270
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if ( '/v1/ping.json' !== strtolower( substr( $resource[0], - strlen( '/v1/ping.json' ) ) ) ) {
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271
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$this->SignRequest( $resource[0], $opts );
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272
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}
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273
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274
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// disable the 'Expect: 100-continue' behaviour. This causes CURL to wait
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275
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// for 2 seconds if the server does not support this header.
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276
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$opts[ CURLOPT_HTTPHEADER ][] = 'Expect:';
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277
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278
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if ( 'https' === substr( strtolower( $pCanonizedPath ), 0, 5 ) ) {
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279
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$opts[ CURLOPT_SSL_VERIFYHOST ] = false;
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280
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$opts[ CURLOPT_SSL_VERIFYPEER ] = false;
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281
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}
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282
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283
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curl_setopt_array( $ch, $opts );
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284
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$result = curl_exec( $ch );
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285
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286
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/*if (curl_errno($ch) == 60) // CURLE_SSL_CACERT
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|
287
|
|
|
{
|
|
288
|
|
|
self::errorLog('Invalid or no certificate authority found, using bundled information');
|
|
289
|
|
|
curl_setopt($ch, CURLOPT_CAINFO,
|
|
290
|
|
|
dirname(__FILE__) . '/fb_ca_chain_bundle.crt');
|
|
291
|
|
|
$result = curl_exec($ch);
|
|
292
|
|
|
}*/
|
|
293
|
|
|
|
|
294
|
|
|
// With dual stacked DNS responses, it's possible for a server to
|
|
295
|
|
|
// have IPv6 enabled but not have IPv6 connectivity. If this is
|
|
296
|
|
|
// the case, curl will try IPv4 first and if that fails, then it will
|
|
297
|
|
|
// fall back to IPv6 and the error EHOSTUNREACH is returned by the
|
|
298
|
|
|
// operating system.
|
|
299
|
|
|
if ( false === $result && empty( $opts[ CURLOPT_IPRESOLVE ] ) ) {
|
|
300
|
|
|
$matches = array();
|
|
301
|
|
|
$regex = '/Failed to connect to ([^:].*): Network is unreachable/';
|
|
302
|
|
|
if ( preg_match( $regex, curl_error( $ch ), $matches ) ) {
|
|
303
|
|
|
if ( strlen( @inet_pton( $matches[1] ) ) === 16 ) {
|
|
304
|
|
|
// self::errorLog('Invalid IPv6 configuration on server, Please disable or get native IPv6 on your server.');
|
|
|
|
|
|
|
305
|
|
|
self::$CURL_OPTS[ CURLOPT_IPRESOLVE ] = CURL_IPRESOLVE_V4;
|
|
306
|
|
|
curl_setopt( $ch, CURLOPT_IPRESOLVE, CURL_IPRESOLVE_V4 );
|
|
307
|
|
|
$result = curl_exec( $ch );
|
|
308
|
|
|
}
|
|
309
|
|
|
}
|
|
310
|
|
|
}
|
|
311
|
|
|
|
|
312
|
|
|
if ( $result === false ) {
|
|
313
|
|
|
$e = new Freemius_Exception( array(
|
|
314
|
|
|
'error' => array(
|
|
315
|
|
|
'code' => curl_errno( $ch ),
|
|
316
|
|
|
'message' => curl_error( $ch ),
|
|
317
|
|
|
'type' => 'CurlException',
|
|
318
|
|
|
),
|
|
319
|
|
|
) );
|
|
320
|
|
|
|
|
321
|
|
|
curl_close( $ch );
|
|
322
|
|
|
throw $e;
|
|
323
|
|
|
}
|
|
324
|
|
|
|
|
325
|
|
|
curl_close( $ch );
|
|
326
|
|
|
|
|
327
|
|
|
if (empty($result))
|
|
328
|
|
|
return null;
|
|
329
|
|
|
|
|
330
|
|
|
$decoded = json_decode( $result );
|
|
331
|
|
|
|
|
332
|
|
|
if ( is_null( $decoded ) ) {
|
|
333
|
|
|
if ( preg_match( '/Please turn JavaScript on/i', $result ) &&
|
|
334
|
|
|
preg_match( '/text\/javascript/', $result )
|
|
335
|
|
|
) {
|
|
336
|
|
|
$this->ThrowCloudFlareDDoSException( $result );
|
|
337
|
|
|
} else if ( preg_match( '/Access control configuration prevents your request from being allowed at this time. Please contact your service provider if you feel this is incorrect./', $result ) &&
|
|
338
|
|
|
preg_match( '/squid/', $result )
|
|
339
|
|
|
) {
|
|
340
|
|
|
$this->ThrowSquidAclException( $result );
|
|
341
|
|
|
} else {
|
|
342
|
|
|
$decoded = (object) array(
|
|
343
|
|
|
'error' => (object) array(
|
|
344
|
|
|
'type' => 'Unknown',
|
|
345
|
|
|
'message' => $result,
|
|
346
|
|
|
'code' => 'unknown',
|
|
347
|
|
|
'http' => 402
|
|
348
|
|
|
)
|
|
349
|
|
|
);
|
|
350
|
|
|
}
|
|
351
|
|
|
}
|
|
352
|
|
|
|
|
353
|
|
|
return $decoded;
|
|
354
|
|
|
}
|
|
355
|
|
|
|
|
356
|
|
|
/**
|
|
357
|
|
|
* @param string $pResult
|
|
358
|
|
|
*
|
|
359
|
|
|
* @throws Freemius_Exception
|
|
360
|
|
|
*/
|
|
361
|
|
|
private function ThrowNoCurlException( $pResult = '' ) {
|
|
362
|
|
|
throw new Freemius_Exception( array(
|
|
363
|
|
|
'error' => (object) array(
|
|
364
|
|
|
'type' => 'cUrlMissing',
|
|
365
|
|
|
'message' => $pResult,
|
|
366
|
|
|
'code' => 'curl_missing',
|
|
367
|
|
|
'http' => 402
|
|
368
|
|
|
)
|
|
369
|
|
|
) );
|
|
370
|
|
|
}
|
|
371
|
|
|
|
|
372
|
|
|
/**
|
|
373
|
|
|
* @param string $pResult
|
|
374
|
|
|
*
|
|
375
|
|
|
* @throws Freemius_Exception
|
|
376
|
|
|
*/
|
|
377
|
|
|
private function ThrowCloudFlareDDoSException( $pResult = '' ) {
|
|
378
|
|
|
throw new Freemius_Exception( array(
|
|
379
|
|
|
'error' => (object) array(
|
|
380
|
|
|
'type' => 'CloudFlareDDoSProtection',
|
|
381
|
|
|
'message' => $pResult,
|
|
382
|
|
|
'code' => 'cloudflare_ddos_protection',
|
|
383
|
|
|
'http' => 402
|
|
384
|
|
|
)
|
|
385
|
|
|
) );
|
|
386
|
|
|
}
|
|
387
|
|
|
|
|
388
|
|
|
/**
|
|
389
|
|
|
* @param string $pResult
|
|
390
|
|
|
*
|
|
391
|
|
|
* @throws Freemius_Exception
|
|
392
|
|
|
*/
|
|
393
|
|
|
private function ThrowSquidAclException( $pResult = '' ) {
|
|
394
|
|
|
throw new Freemius_Exception( array(
|
|
395
|
|
|
'error' => (object) array(
|
|
396
|
|
|
'type' => 'SquidCacheBlock',
|
|
397
|
|
|
'message' => $pResult,
|
|
398
|
|
|
'code' => 'squid_cache_block',
|
|
399
|
|
|
'http' => 402
|
|
400
|
|
|
)
|
|
401
|
|
|
) );
|
|
402
|
|
|
}
|
|
403
|
|
|
} |
The PSR-1: Basic Coding Standard recommends that a file should either introduce new symbols, that is classes, functions, constants or similar, or have side effects. Side effects are anything that executes logic, like for example printing output, changing ini settings or writing to a file.
The idea behind this recommendation is that merely auto-loading a class should not change the state of an application. It also promotes a cleaner style of programming and makes your code less prone to errors, because the logic is not spread out all over the place.
To learn more about the PSR-1, please see the PHP-FIG site on the PSR-1.