java.net

Class NetPermission

java.lang.Object

java.security.Permission

java.security.BasicPermission

java.net.NetPermission

All Implemented Interfaces:

Serializable, Guard

public final class NetPermission
extends BasicPermission

This class is for various network permissions. A NetPermission contains a name (also referred to as a "target name") but no actions list; you either have the named permission or you don't.

The target name is the name of the network permission (see below). The naming convention follows the hierarchical property naming convention. Also, an asterisk may appear at the end of the name, following a ".", or by itself, to signify a wildcard match. For example: "foo.*" and "*" signify a wildcard match, while "*foo" and "a*b" do not.

The following table lists all the possible NetPermission target names, and for each provides a description of what the permission allows and a discussion of the risks of granting code the permission.

Permission Target Name	What the Permission Allows	Risks of Allowing this Permission
allowHttpTrace	The ability to use the HTTP TRACE method in HttpURLConnection.	Malicious code using HTTP TRACE could get access to security sensitive information in the HTTP headers (such as cookies) that it might not otherwise have access to.
getCookieHandler	The ability to get the cookie handler that processes highly security sensitive cookie information for an Http session.	Malicious code can get a cookie handler to obtain access to highly security sensitive cookie information. Some web servers use cookies to save user private information such as access control information, or to track user browsing habit.
getNetworkInformation	The ability to retrieve all information about local network interfaces.	Malicious code can read information about network hardware such as MAC addresses, which could be used to construct local IPv6 addresses.
getProxySelector	The ability to get the proxy selector used to make decisions on which proxies to use when making network connections.	Malicious code can get a ProxySelector to discover proxy hosts and ports on internal networks, which could then become targets for attack.
getResponseCache	The ability to get the response cache that provides access to a local response cache.	Malicious code getting access to the local response cache could access security sensitive information.
requestPasswordAuthentication	The ability to ask the authenticator registered with the system for a password	Malicious code may steal this password.
setCookieHandler	The ability to set the cookie handler that processes highly security sensitive cookie information for an Http session.	Malicious code can set a cookie handler to obtain access to highly security sensitive cookie information. Some web servers use cookies to save user private information such as access control information, or to track user browsing habit.
setDefaultAuthenticator	The ability to set the way authentication information is retrieved when a proxy or HTTP server asks for authentication	Malicious code can set an authenticator that monitors and steals user authentication input as it retrieves the input from the user.
setProxySelector	The ability to set the proxy selector used to make decisions on which proxies to use when making network connections.	Malicious code can set a ProxySelector that directs network traffic to an arbitrary network host.
setResponseCache	The ability to set the response cache that provides access to a local response cache.	Malicious code getting access to the local response cache could access security sensitive information, or create false entries in the response cache.
specifyStreamHandler	The ability to specify a stream handler when constructing a URL	Malicious code may create a URL with resources that it would normally not have access to (like file:/foo/fum/), specifying a stream handler that gets the actual bytes from someplace it does have access to. Thus it might be able to trick the system into creating a ProtectionDomain/CodeSource for a class even though that class really didn't come from that location.

Author:

Marianne Mueller, Roland Schemers

See Also:

Permission, SecurityManager, Serialized Form

Constructor Summary

Constructors

Constructor and Description
NetPermission(String name) Creates a new NetPermission with the specified name.
NetPermission(String name, String actions) Creates a new NetPermission object with the specified name.

Method Summary

Methods inherited from class java.security.BasicPermission

equals, getActions, hashCode, implies

Methods inherited from class java.security.Permission

getName, toString

Methods inherited from class java.lang.Object

clone, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

NetPermission

public NetPermission(String name)

Creates a new NetPermission with the specified name. The name is the symbolic name of the NetPermission, such as "setDefaultAuthenticator", etc. An asterisk may appear at the end of the name, following a ".", or by itself, to signify a wildcard match.

Parameters:

name - the name of the NetPermission.

Throws:

NullPointerException - if name is null.

IllegalArgumentException - if name is empty.

NetPermission

public NetPermission(String name,
                     @Nullable
                     String actions)

Creates a new NetPermission object with the specified name. The name is the symbolic name of the NetPermission, and the actions String is currently unused and should be null.

Parameters:

name - the name of the NetPermission.

actions - should be null.

Throws:

NullPointerException - if name is null.

IllegalArgumentException - if name is empty.