lib/Beberlei/AzureBlobStorage/SharedAccessSignature.php
public function permissionMatchesRequest(
    	$permissionUrl = '',
    	$requestUrl = '',
    	$resourceType = Storage::RESOURCE_UNKNOWN,
    	$requiredPermission = CredentialsAbstract::PERMISSION_READ
    ) {
        // Build requirements
        $requiredResourceType = $resourceType;
        if ($requiredResourceType == Storage::RESOURCE_BLOB) {
            $requiredResourceType .= 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 permissionMatchesRequest(
    	$permissionUrl = '',
    	$requestUrl = '',
    	$resourceType = Storage::RESOURCE_UNKNOWN,
    	$requiredPermission = CredentialsAbstract::PERMISSION_READ
    ) {
        // Build requirements
        $requiredResourceType = $resourceType;
        if ($requiredResourceType == Storage::RESOURCE_BLOB) {
            $requiredResourceType .= 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;
    }
Permission matches request?

@param string $permissionUrl Permission URL
@param string $requestUrl Request URL
@param string $resourceType Resource type
@param string $requiredPermission Required permission
@return string Signed request URL