C:/xampp/htdocs/moodle/lib/zend/Zend/Service/WindowsAzure/Credentials/SharedAccessSignature.php

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<?php
require_once 'Zend/Service/WindowsAzure/Credentials/CredentialsAbstract.php';

require_once 'Zend/Service/WindowsAzure/Storage.php';

require_once 'Zend/Http/Client.php';

class Zend_Service_WindowsAzure_Credentials_SharedAccessSignature
    extends Zend_Service_WindowsAzure_Credentials_CredentialsAbstract
{
    protected $_permissionSet = array();
    
        public function __construct(
                $accountName = Zend_Service_WindowsAzure_Credentials_CredentialsAbstract::DEVSTORE_ACCOUNT,
                $accountKey  = Zend_Service_WindowsAzure_Credentials_CredentialsAbstract::DEVSTORE_KEY,
                $usePathStyleUri = false, $permissionSet = array()
        ) {
            parent::__construct($accountName, $accountKey, $usePathStyleUri);
            $this->_permissionSet = $permissionSet;
        }
        
    public function getPermissionSet()
        {
            return $this->_permissionSet;   
        }
        
    public function setPermissionSet($value = array())
        {
                foreach ($value as $url) {
                        if (strpos($url, $this->_accountName) === false) {
                                throw new Zend_Service_WindowsAzure_Exception('The permission set can only contain URLs for the account name specified in the Zend_Service_WindowsAzure_Credentials_SharedAccessSignature instance.');
                        }
                }
            $this->_permissionSet = $value;
        }
    
    public function createSignature(
        $path = '/',
        $resource = 'b',
        $permissions = 'r',
        $start = '',
        $expiry = '',
        $identifier = ''
    ) {
                // Determine path
                if ($this->_usePathStyleUri) {
                        $path = substr($path, strpos($path, '/'));
                }
                        
                // Add trailing slash to $path
                if (substr($path, 0, 1) !== '/') {
                    $path = '/' . $path;
                }

                // Build canonicalized resource string
                $canonicalizedResource  = '/' . $this->_accountName;
                /*if ($this->_usePathStyleUri) {
                        $canonicalizedResource .= '/' . $this->_accountName;
                }*/
                $canonicalizedResource .= $path;
                    
                // Create string to sign   
                $stringToSign   = array();
                $stringToSign[] = $permissions;
        $stringToSign[] = $start;
        $stringToSign[] = $expiry;
        $stringToSign[] = $canonicalizedResource;
        $stringToSign[] = $identifier;

        $stringToSign = implode("\n", $stringToSign);
        $signature    = base64_encode(hash_hmac('sha256', $stringToSign, $this->_accountKey, true));
        
        return $signature;
    }

    public function createSignedQueryString(
        $path = '/',
        $queryString = '',
        $resource = 'b',
        $permissions = 'r',
        $start = '',
        $expiry = '',
        $identifier = ''
    ) {
        // Parts
        $parts = array();
        if ($start !== '') {
            $parts[] = 'st=' . urlencode($start);
        }
        $parts[] = 'se=' . urlencode($expiry);
        $parts[] = 'sr=' . $resource;
        $parts[] = 'sp=' . $permissions;
        if ($identifier !== '') {
            $parts[] = 'si=' . urlencode($identifier);
        }
        $parts[] = 'sig=' . urlencode($this->createSignature($path, $resource, $permissions, $start, $expiry, $identifier));

        // Assemble parts and query string
        if ($queryString != '') {
            $queryString .= '&';
            }
        $queryString .= implode('&', $parts);

        return $queryString;
    }
    
    public function permissionMatchesRequest(
        $permissionUrl = '',
        $requestUrl = '',
        $resourceType = Zend_Service_WindowsAzure_Storage::RESOURCE_UNKNOWN,
        $requiredPermission = Zend_Service_WindowsAzure_Credentials_CredentialsAbstract::PERMISSION_READ
    ) {
        // Build requirements
        $requiredResourceType = $resourceType;
        if ($requiredResourceType == Zend_Service_WindowsAzure_Storage::RESOURCE_BLOB) {
            $requiredResourceType .= Zend_Service_WindowsAzure_Storage::RESOURCE_CONTAINER;
        }

        // Parse permission url
            $parsedPermissionUrl = parse_url($permissionUrl);
            
            // Parse permission properties
            $permissionParts = explode('&', $parsedPermissionUrl['query']);
            
            // Parse request url
            $parsedRequestUrl = parse_url($requestUrl);
            
            // Check if permission matches request
            $matches = true;
            foreach ($permissionParts as $part) {
                list($property, $value) = explode('=', $part, 2);
                
                if ($property == 'sr') {
                    $matches = $matches && (strpbrk($value, $requiredResourceType) !== false);
                }
                
                if ($property == 'sp') {
                    $matches = $matches && (strpbrk($value, $requiredPermission) !== false);
                }
            }
            
            // Ok, but... does the resource match?
            $matches = $matches && (strpos($parsedRequestUrl['path'], $parsedPermissionUrl['path']) !== false);
            
        // Return
            return $matches;
    }    
    
        public function signRequestUrl(
                $requestUrl = '',
                $resourceType = Zend_Service_WindowsAzure_Storage::RESOURCE_UNKNOWN,
                $requiredPermission = Zend_Service_WindowsAzure_Credentials_CredentialsAbstract::PERMISSION_READ
        ) {
            // Look for a matching permission
            foreach ($this->getPermissionSet() as $permittedUrl) {
                if ($this->permissionMatchesRequest($permittedUrl, $requestUrl, $resourceType, $requiredPermission)) {
                    // This matches, append signature data
                    $parsedPermittedUrl = parse_url($permittedUrl);

                    if (strpos($requestUrl, '?') === false) {
                        $requestUrl .= '?';
                    } else {
                        $requestUrl .= '&';
                    }
                    
                    $requestUrl .= $parsedPermittedUrl['query'];

                    // Return url
                    return $requestUrl;
                }
            }
            
            // Return url, will be unsigned...
            return $requestUrl;
        }
    
        public function signRequestHeaders(
                $httpVerb = Zend_Http_Client::GET,
                $path = '/',
                $queryString = '',
                $headers = null,
                $forTableStorage = false,
                $resourceType = Zend_Service_WindowsAzure_Storage::RESOURCE_UNKNOWN,
                $requiredPermission = Zend_Service_WindowsAzure_Credentials_CredentialsAbstract::PERMISSION_READ
        ) {
            return $headers;
        }
}