The target name is the name of a security configuration parameter (see below). Currently the SecurityPermission object is used to guard access to the Policy, Security, Provider, Signer, and Identity objects.
The following table lists all the possible SecurityPermission 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 |
---|---|---|
createAccessControlContext | Creation of an AccessControlContext | This allows someone to instantiate an AccessControlContext
with a DomainCombiner . Since DomainCombiners are given
a reference to the ProtectionDomains currently on the stack,
this could potentially lead to a privacy leak if the DomainCombiner
is malicious. |
getDomainCombiner | Retrieval of an AccessControlContext's DomainCombiner | This allows someone to retrieve an AccessControlContext's
DomainCombiner . Since DomainCombiners may contain
sensitive information, this could potentially lead to a privacy leak. |
getPolicy | Retrieval of the system-wide security policy (specifically, of the currently-installed Policy object) | This allows someone to query the policy via the
getPermissions call,
which discloses which permissions would be granted to a given CodeSource.
While revealing the policy does not compromise the security of
the system, it does provide malicious code with additional information
which it may use to better aim an attack. It is wise
not to divulge more information than necessary. |
setPolicy | Setting of the system-wide security policy (specifically, the Policy object) | Granting this permission is extremely dangerous, as malicious code may grant itself all the necessary permissions it needs to successfully mount an attack on the system. |
getProperty.{key} | Retrieval of the security property with the specified key | Depending on the particular key for which access has been granted, the code may have access to the list of security providers, as well as the location of the system-wide and user security policies. while revealing this information does not compromise the security of the system, it does provide malicious code with additional information which it may use to better aim an attack. |
setProperty.{key} | Setting of the security property with the specified key | This could include setting a security provider or defining the location of the the system-wide security policy. Malicious code that has permission to set a new security provider may set a rogue provider that steals confidential information such as cryptographic private keys. In addition, malicious code with permission to set the location of the system-wide security policy may point it to a security policy that grants the attacker all the necessary permissions it requires to successfully mount an attack on the system. |
insertProvider.{provider name} | Addition of a new provider, with the specified name | This would allow somebody to introduce a possibly malicious provider (e.g., one that discloses the private keys passed to it) as the highest-priority provider. This would be possible because the Security object (which manages the installed providers) currently does not check the integrity or authenticity of a provider before attaching it. |
removeProvider.{provider name} | Removal of the specified provider | This may change the behavior or disable execution of other parts of the program. If a provider subsequently requested by the program has been removed, execution may fail. Also, if the removed provider is not explicitly requested by the rest of the program, but it would normally be the provider chosen when a cryptography service is requested (due to its previous order in the list of providers), a different provider will be chosen instead, or no suitable provider will be found, thereby resulting in program failure. |
setSystemScope | Setting of the system identity scope | This would allow an attacker to configure the system identity scope with certificates that should not be trusted, thereby granting applet or application code signed with those certificates privileges that would have been denied by the system's original identity scope |
setIdentityPublicKey | Setting of the public key for an Identity | If the identity is marked as "trusted", this allows an attacker to introduce a different public key (e.g., its own) that is not trusted by the system's identity scope, thereby granting applet or application code signed with that public key privileges that would have been denied otherwise. |
setIdentityInfo | Setting of a general information string for an Identity | This allows attackers to set the general description for an identity. This may trick applications into using a different identity than intended or may prevent applications from finding a particular identity. |
addIdentityCertificate | Addition of a certificate for an Identity | This allows attackers to set a certificate for an identity's public key. This is dangerous because it affects the trust relationship across the system. This public key suddenly becomes trusted to a wider audience than it otherwise would be. |
removeIdentityCertificate | Removal of a certificate for an Identity | This allows attackers to remove a certificate for an identity's public key. This is dangerous because it affects the trust relationship across the system. This public key suddenly becomes considered less trustworthy than it otherwise would be. |
printIdentity | Viewing the name of a principal and optionally the scope in which it is used, and whether or not it is considered "trusted" in that scope | The scope that is printed out may be a filename, in which case
it may convey local system information. For example, here's a sample
printout of an identity named "carol", who is
marked not trusted in the user's identity database: carol[/home/luehe/identitydb.obj][not trusted] |
clearProviderProperties.{provider name} | "Clearing" of a Provider so that it no longer contains the properties used to look up services implemented by the provider | This disables the lookup of services implemented by the provider. This may thus change the behavior or disable execution of other parts of the program that would normally utilize the Provider, as described under the "removeProvider.{provider name}" permission. |
putProviderProperty.{provider name} | Setting of properties for the specified Provider | The provider properties each specify the name and location of a particular service implemented by the provider. By granting this permission, you let code replace the service specification with another one, thereby specifying a different implementation. |
removeProviderProperty.{provider name} | Removal of properties from the specified Provider | This disables the lookup of services implemented by the provider. They are no longer accessible due to removal of the properties specifying their names and locations. This may change the behavior or disable execution of other parts of the program that would normally utilize the Provider, as described under the "removeProvider.{provider name}" permission. |
getSignerPrivateKey | Retrieval of a Signer's private key | It is very dangerous to allow access to a private key; private keys are supposed to be kept secret. Otherwise, code can use the private key to sign various files and claim the signature came from the Signer. |
setSignerKeyPair | Setting of the key pair (public key and private key) for a Signer | This would allow an attacker to replace somebody else's (the "target's") keypair with a possibly weaker keypair (e.g., a keypair of a smaller keysize). This also would allow the attacker to listen in on encrypted communication between the target and its peers. The target's peers might wrap an encryption session key under the target's "new" public key, which would allow the attacker (who possesses the corresponding private key) to unwrap the session key and decipher the communication data encrypted under that session key. |
SecurityManager.checkPermission
method is called,
passing this permission object as the permission to check.
Returns silently if access is granted. Otherwise, throws
a SecurityException.java.io.FilePermission
,
the name will be a pathname.getName().hashCode()
, where getName
is
from the Permission superclass.More specifically, this method returns true if:
A BasicPermissionCollection stores a collection of BasicPermission permissions.
BasicPermission objects must be stored in a manner that allows them
to be inserted in any order, but that also enables the
PermissionCollection implies
method
to be implemented in an efficient (and consistent) manner.
wait
methods.
The awakened thread will not be able to proceed until the current thread relinquishes the lock on this object. The awakened thread will compete in the usual manner with any other threads that might be actively competing to synchronize on this object; for example, the awakened thread enjoys no reliable privilege or disadvantage in being the next thread to lock this object.
This method should only be called by a thread that is the owner of this object's monitor. A thread becomes the owner of the object's monitor in one of three ways:
synchronized
statement
that synchronizes on the object.
Class,
by executing a
synchronized static method of that class.
Only one thread at a time can own an object's monitor.
wait
methods.
The awakened threads will not be able to proceed until the current thread relinquishes the lock on this object. The awakened threads will compete in the usual manner with any other threads that might be actively competing to synchronize on this object; for example, the awakened threads enjoy no reliable privilege or disadvantage in being the next thread to lock this object.
This method should only be called by a thread that is the owner
of this object's monitor. See the notify
method for a
description of the ways in which a thread can become the owner of
a monitor.
The current thread must own this object's monitor. The thread
releases ownership of this monitor and waits until another thread
notifies threads waiting on this object's monitor to wake up
either through a call to the notify
method or the
notifyAll
method. The thread then waits until it can
re-obtain ownership of the monitor and resumes execution.
As in the one argument version, interrupts and spurious wakeups are possible, and this method should always be used in a loop:
synchronized (obj) { while (<condition does not hold>) obj.wait(); ... // Perform action appropriate to condition }This method should only be called by a thread that is the owner of this object's monitor. See the
notify
method for a
description of the ways in which a thread can become the owner of
a monitor.The current thread must own this object's monitor.
This method causes the current thread (call it T) to place itself in the wait set for this object and then to relinquish any and all synchronization claims on this object. Thread T becomes disabled for thread scheduling purposes and lies dormant until one of four things happens:
A thread can also wake up without being notified, interrupted, or timing out, a so-called spurious wakeup. While this will rarely occur in practice, applications must guard against it by testing for the condition that should have caused the thread to be awakened, and continuing to wait if the condition is not satisfied. In other words, waits should always occur in loops, like this one:
synchronized (obj) { while (<condition does not hold>) obj.wait(timeout); ... // Perform action appropriate to condition }(For more information on this topic, see Section 3.2.3 in Doug Lea's "Concurrent Programming in Java (Second Edition)" (Addison-Wesley, 2000), or Item 50 in Joshua Bloch's "Effective Java Programming Language Guide" (Addison-Wesley, 2001).
If the current thread is interrupted by another thread while it is waiting, then an InterruptedException is thrown. This exception is not thrown until the lock status of this object has been restored as described above.
Note that the wait method, as it places the current thread into the wait set for this object, unlocks only this object; any other objects on which the current thread may be synchronized remain locked while the thread waits.
This method should only be called by a thread that is the owner
of this object's monitor. See the notify
method for a
description of the ways in which a thread can become the owner of
a monitor.
This method is similar to the wait
method of one
argument, but it allows finer control over the amount of time to
wait for a notification before giving up. The amount of real time,
measured in nanoseconds, is given by:
1000000*timeout+nanos
In all other respects, this method does the same thing as the method of one argument. In particular, wait(0, 0) means the same thing as wait(0).
The current thread must own this object's monitor. The thread releases ownership of this monitor and waits until either of the following two conditions has occurred:
notify
method
or the notifyAll
method.
timeout
milliseconds plus nanos
nanoseconds arguments, has
elapsed.
The thread then waits until it can re-obtain ownership of the monitor and resumes execution.
As in the one argument version, interrupts and spurious wakeups are possible, and this method should always be used in a loop:
synchronized (obj) { while (<condition does not hold>) obj.wait(timeout, nanos); ... // Perform action appropriate to condition }This method should only be called by a thread that is the owner of this object's monitor. See the
notify
method for a
description of the ways in which a thread can become the owner of
a monitor.