Runkit_Sandbox
(PECL runkit >= 0.7.0)
Runkit_Sandbox — Runkit Sandbox Class -- PHP Virtual Machine
说明
Instantiating the Runkit_Sandbox class creates a new thread with its own scope and program stack. Using a set of options passed to the constructor, this environment may be restricted to a subset of what the primary interpreter can do and provide a safer environment for executing user supplied code.
Note: 沙箱支持(是 runkit_lint(),runkit_lint_file() 函数,与 Runkit_Sandbox 类所必需)仅可用于 PHP 5.1.0 或 PHP 5.0 的特别修补版本,并需启用线程安全。更多信息可参见 runkit 包中的 README 文件。
Constructor
$options
] ) : void
options
is an associative array containing
any combination of the special ini options listed below.
-
safe_mode
-
If the outer script which is instantiating the Runkit_Sandbox class is configured with safe_mode = off, then safe_mode may be turned on for the sandbox environment. This setting can not be used to disable safe_mode when it's already enabled in the outer script.
-
safe_mode_gid
-
If the outer script which is instantiating the Runkit_Sandbox class is configured with safe_mode_gid = on, then safe_mode_gid may be turned off for the sandbox environment. This setting can not be used to enable safe_mode_gid when it's already disabled in the outer script.
-
safe_mode_include_dir
-
If the outer script which is instantiating the Runkit_Sandbox class is configured with a safe_mode_include_dir, then a new safe_mode_include_dir may be set for sandbox environments below the currently defined value. safe_mode_include_dir may also be cleared to indicate that the bypass feature is disabled. If safe_mode_include_dir was blank in the outer script, but safe_mode was not enabled, then any arbitrary safe_mode_include_dir may be set while turning safe_mode on.
-
open_basedir
-
open_basedir
may be set to any path below the current setting of open_basedir. If open_basedir is not set within the global scope, then it is assumed to be the root directory and may be set to any location. -
allow_url_fopen
-
Like
safe_mode
, this setting can only be made more restrictive, in this case by setting it toFALSE
when it is previously set toTRUE
-
disable_functions
-
Comma separated list of functions to disable within the sandbox sub-interpreter. This list need not contain the names of the currently disabled functions, they will remain disabled whether listed here or not.
-
disable_classes
-
Comma separated list of classes to disable within the sandbox sub-interpreter. This list need not contain the names of the currently disabled classes, they will remain disabled whether listed here or not.
-
runkit.superglobal
-
Comma separated list of variables to be treated as superglobals within the sandbox sub-interpreter. These variables will be used in addition to any variables defined internally or through the global runkit.superglobal setting.
-
runkit.internal_override
-
Ini option runkit.internal_override may be disabled (but not re-enabled) within sandboxes.
Example #1 Instantiating a restricted sandbox
<?php
$options = array(
'safe_mode'=>true,
'open_basedir'=>'/var/www/users/jdoe/',
'allow_url_fopen'=>'false',
'disable_functions'=>'exec,shell_exec,passthru,system',
'disable_classes'=>'myAppClass');
$sandbox = new Runkit_Sandbox($options);
/* Non-protected ini settings may set normally */
$sandbox->ini_set('html_errors',true);
?>
Accessing Variables
All variables in the global scope of the sandbox environment are accessible as properties of the sandbox object. The first thing to note is that because of the way memory between these two threads is managed, object and resource variables can not currently be exchanged between interpreters. Additionally, all arrays are deep copied and any references will be lost. This also means that references between interpreters are not possible.
Example #2 Working with variables in a sandbox
<?php
$sandbox = new Runkit_Sandbox();
$sandbox->foo = 'bar';
$sandbox->eval('echo "$foo\n"; $bar = $foo . "baz";');
echo "{$sandbox->bar}\n";
if (isset($sandbox->foo)) unset($sandbox->foo);
$sandbox->eval('var_dump(isset($foo));');
?>
以上例程会输出:
bar barbaz bool(false)
Calling PHP Functions
Any function defined within the sandbox may be called as a method on the sandbox object. This also includes a few pseudo-function language constructs: eval(), include, include_once, require, require_once, echo, print, die(), and exit().
Example #3 Calling sandbox functions
<?php
$sandbox = new Runkit_Sandbox();
echo $sandbox->str_replace('a','f','abc');
?>
以上例程会输出:
fbc
When passing arguments to a sandbox function, the arguments are taken from the outer instance of PHP. If you wish to pass arguments from the sandbox's scope, be sure to access them as properties of the sandbox object as illustrated above.
Example #4 Passing arguments to sandbox functions
<?php
$sandbox = new Runkit_Sandbox();
$foo = 'bar';
$sandbox->foo = 'baz';
echo $sandbox->str_replace('a',$foo,'a');
echo $sandbox->str_replace('a',$sandbox->foo,'a');
?>
以上例程会输出:
bar baz
Changing Sandbox Settings
As of runkit version 0.5, certain Sandbox settings may
be modified on the fly using ArrayAccess syntax.
Some settings, such as active
are read-only and meant to provide status information.
Other settings, such as output_handler
may be set and read much like a normal array offset.
Future settings may be write-only, however no such
settings currently exist.
Setting | Type | Purpose | Default |
---|---|---|---|
active | Boolean (Read Only) |
TRUE if the Sandbox is still in a usable state,
FALSE if the request is in bailout due to a
call to die(), exit(), or because of a fatal
error condition.
|
TRUE (Initial) |
output_handler | Callback | When set to a valid callback, all output generated by the Sandbox instance will be processed through the named function. Sandbox output handlers follow the same calling conventions as the system-wide output handler. | None |
parent_access | Boolean | May the sandbox use instances of the Runkit_Sandbox_Parent class? Must be enabled for other Runkit_Sandbox_Parent related settings to work. | FALSE |
parent_read | Boolean | May the sandbox read variables in its parent's context? | FALSE |
parent_write | Boolean | May the sandbox modify variables in its parent's context? | FALSE |
parent_eval | Boolean | May the sandbox evaluate arbitrary code in its parent's context? DANGEROUS | FALSE |
parent_include | Boolean | May the sandbox include php code files in its parent's context? DANGEROUS | FALSE |
parent_echo | Boolean | May the sandbox echo data in its parent's context effectively bypassing its own output_handler? | FALSE |
parent_call | Boolean | May the sandbox call functions in its parent's context? | FALSE |
parent_die | Boolean | May the sandbox kill its own parent? (And thus itself) | FALSE |
parent_scope | Integer | What scope will parental property access look at? 0 == Global scope, 1 == Calling scope, 2 == Scope preceding calling scope, 3 == The scope before that, etc..., etc... | 0 (Global) |
parent_scope | String | When parent_scope is set to a string value, it refers to a named array variable in the global scope. If the named variable does not exist at the time of access it will be created as an empty array. If the variable exists but it not an array, a dummy array will be created containing a reference to the named global variable. |