java.security
Class KeyStore

java.lang.Object   
  java.security.KeyStore

public class KeyStore
extends Object   

This class represents a storage facility for cryptographic keys and certificates.

A KeyStore manages different types of entries. Each type of entry implements the KeyStore.Entry interface. Three basic KeyStore.Entry implementations are provided:

• KeyStore.PrivateKeyEntry

  This type of entry holds a cryptographic PrivateKey, which is optionally stored in a protected format to prevent unauthorized access. It is also accompanied by a certificate chain for the corresponding public key.

  Private keys and certificate chains are used by a given entity for self-authentication. Applications for this authentication include software distribution organizations which sign JAR files as part of releasing and/or licensing software.

• KeyStore.SecretKeyEntry

  This type of entry holds a cryptographic SecretKey, which is optionally stored in a protected format to prevent unauthorized access.

• KeyStore.TrustedCertificateEntry

  This type of entry contains a single public key Certificate belonging to another party. It is called a trusted certificate because the keystore owner trusts that the public key in the certificate indeed belongs to the identity identified by the subject (owner) of the certificate.

  This type of entry can be used to authenticate other parties.

Each entry in a keystore is identified by an "alias" string. In the case of private keys and their associated certificate chains, these strings distinguish among the different ways in which the entity may authenticate itself. For example, the entity may authenticate itself using different certificate authorities, or using different public key algorithms.

Whether keystores are persistent, and the mechanisms used by the keystore if it is persistent, are not specified here. This allows use of a variety of techniques for protecting sensitive (e.g., private or secret) keys. Smart cards or other integrated cryptographic engines (SafeKeyper) are one option, and simpler mechanisms such as files may also be used (in a variety of formats).

Typical ways to request a KeyStore object include relying on the default type and providing a specific keystore type.

• To rely on the default type:

      KeyStore ks = KeyStore.getInstance(KeyStore.getDefaultType());
   

  The system will return a keystore implementation for the default type.

• To provide a specific keystore type:

        KeyStore ks = KeyStore.getInstance("JKS");
   

  The system will return the most preferred implementation of the specified keystore type available in the environment.

Before a keystore can be accessed, it must be loaded .

    KeyStore ks = KeyStore.getInstance(KeyStore.getDefaultType());

    // get user password and file input stream
    char[] password = getPassword();
    java.io.FileInputStream fis =
        new java.io.FileInputStream("keyStoreName");
    ks.load(fis, password);
    fis.close();
 

To create an empty keystore using the above load method, pass null as the InputStream argument.

Once the keystore has been loaded, it is possible to read existing entries from the keystore, or to write new entries into the keystore:

    // get my private key
    KeyStore.PrivateKeyEntry pkEntry = (KeyStore.PrivateKeyEntry)
        ks.getEntry("privateKeyAlias", password);
    PrivateKey myPrivateKey = pkEntry.getPrivateKey();

    // save my secret key
    javax.crypto.SecretKey mySecretKey;
    KeyStore.SecretKeyEntry skEntry =
        new KeyStore.SecretKeyEntry(mySecretKey);
    ks.setEntry("secretKeyAlias", skEntry, password);

    // store away the keystore
    java.io.FileOutputStream fos =
        new java.io.FileOutputStream("newKeyStoreName");
    ks.store(fos, password);
    fos.close();
 

Note that although the same password may be used to load the keystore, to protect the private key entry, to protect the secret key entry, and to store the keystore (as is shown in the sample code above), different passwords or other protection parameters may also be used.

Since:

1.2

See Also:

PrivateKey , SecretKey, Certificate

Nested Class Summary

static class	KeyStore.Builder A description of a to-be-instantiated KeyStore object.
static class	KeyStore.CallbackHandlerProtection A ProtectionParameter encapsulating a CallbackHandler.
static interface	KeyStore.Entry A marker interface for KeyStore entry types.
static interface	KeyStore.LoadStoreParameter A marker interface for KeyStore load and store parameters.
static class	KeyStore.PasswordProtection A password-based implementation of ProtectionParameter.
static class	KeyStore.PrivateKeyEntry A KeyStore entry that holds a PrivateKey and corresponding certificate chain.
static interface	KeyStore.ProtectionParameter A marker interface for keystore protection parameters.
static class	KeyStore.SecretKeyEntry A KeyStore entry that holds a SecretKey.
static class	KeyStore.TrustedCertificateEntry A KeyStore entry that holds a trusted Certificate.

Constructor Summary

protected

KeyStore (KeyStoreSpi keyStoreSpi, Provider provider, String type) Creates a KeyStore object of the given type, and encapsulates the given provider implementation (SPI object) in it.

Method Summary

Enumeration <String >	aliases () Lists all the alias names of this keystore.
boolean	containsAlias (String alias) Checks if the given alias exists in this keystore.
void	deleteEntry (String alias) Deletes the entry identified by the given alias from this keystore.
boolean	entryInstanceOf (String alias, Class <? extends KeyStore.Entry > entryClass) Determines if the keystore Entry for the specified alias is an instance or subclass of the specified entryClass.
Certificate	getCertificate (String alias) Returns the certificate associated with the given alias.
String	getCertificateAlias (Certificate cert) Returns the (alias) name of the first keystore entry whose certificate matches the given certificate.
Certificate []	getCertificateChain (String alias) Returns the certificate chain associated with the given alias.
Date	getCreationDate (String alias) Returns the creation date of the entry identified by the given alias.
static String	getDefaultType () Returns the default keystore type as specified in the Java security properties file, or the string "jks" (acronym for "Java keystore") if no such property exists.
KeyStore.Entry	getEntry (String alias, KeyStore.ProtectionParameter protParam) Gets a keystore Entry for the specified alias with the specified protection parameter.
static KeyStore	getInstance (String type) Generates a keystore object of the given type.
static KeyStore	getInstance (String type, Provider provider) Generates a keystore object for the specified keystore type from the specified provider.
static KeyStore	getInstance (String type, String provider) Generates a keystore object for the specified keystore type from the specified provider.
Key	getKey (String alias, char[] password) Returns the key associated with the given alias, using the given password to recover it.
Provider	getProvider () Returns the provider of this keystore.
String	getType () Returns the type of this keystore.
boolean	isCertificateEntry (String alias) Returns true if the entry identified by the given alias was created by a call to setCertificateEntry, or created by a call to setEntry with a TrustedCertificateEntry.
boolean	isKeyEntry (String alias) Returns true if the entry identified by the given alias was created by a call to setKeyEntry, or created by a call to setEntry with a PrivateKeyEntry or a SecretKeyEntry.
void	load (InputStream stream, char[] password) Loads this KeyStore from the given input stream.
void	load (KeyStore.LoadStoreParameter param) Loads this keystore using the given LoadStoreParameter.
void	setCertificateEntry (String alias, Certificate cert) Assigns the given trusted certificate to the given alias.
void	setEntry (String alias, KeyStore.Entry entry, KeyStore.ProtectionParameter protParam) Saves a keystore Entry under the specified alias.
void	setKeyEntry (String alias, byte[] key, Certificate [] chain) Assigns the given key (that has already been protected) to the given alias.
void	setKeyEntry (String alias, Key key, char[] password, Certificate [] chain) Assigns the given key to the given alias, protecting it with the given password.
int	size () Retrieves the number of entries in this keystore.
void	store (KeyStore.LoadStoreParameter param) Stores this keystore using the given LoadStoreParameter.
void	store (OutputStream stream, char[] password) Stores this keystore to the given output stream, and protects its integrity with the given password.

Methods inherited from class java.lang.Object

clone , equals , finalize , getClass , hashCode , notify , notifyAll , toString , wait , wait , wait

Constructor Detail

KeyStore

protected KeyStore(KeyStoreSpi    keyStoreSpi,
                   Provider    provider,
                   String    type)

Creates a KeyStore object of the given type, and encapsulates the given provider implementation (SPI object) in it.

Parameters:

keyStoreSpi - the provider implementation.

provider - the provider.

type - the keystore type.

Method Detail

getInstance

public static KeyStore    getInstance(String    type)
                            throws KeyStoreException   

Generates a keystore object of the given type.

If the default provider package provides a keystore implementation of the given type, an instance of KeyStore containing that implementation is returned. If the requested keystore type is not available in the default package, other packages are searched.

Parameters:

type - the type of keystore. See Appendix A in the Java Cryptography Architecture API Specification & Reference for information about standard keystore types.

Returns:

a keystore object of the specified type.

Throws:

KeyStoreException - if the requested keystore type is not available in the default provider package or any of the other provider packages that were searched.

getInstance

public static KeyStore    getInstance(String    type,
                                   String    provider)
                            throws KeyStoreException   ,
                                   NoSuchProviderException   

Generates a keystore object for the specified keystore type from the specified provider.

Parameters:

type - the type of keystore. See Appendix A in the Java Cryptography Architecture API Specification & Reference for information about standard keystore types.

provider - the name of the provider.

Returns:

a keystore object of the specified type, as supplied by the specified provider.

Throws:

KeyStoreException - if the requested keystore type is not available from the provider.

NoSuchProviderException - if the provider has not been configured.

IllegalArgumentException - if the provider name is null or empty.

See Also:

Provider

getInstance

public static KeyStore    getInstance(String    type,
                                   Provider    provider)
                            throws KeyStoreException   

Generates a keystore object for the specified keystore type from the specified provider. Note: the provider doesn't have to be registered.

Parameters:

type - the type of keystore. See Appendix A in the Java Cryptography Architecture API Specification & Reference for information about standard keystore types.

provider - the provider.

Returns:

a keystore object of the specified type, as supplied by the specified provider.

Throws:

KeyStoreException - if the requested keystore type is not available from the provider.

IllegalArgumentException - if the provider is null.

Since:

1.4

See Also:

Provider

getDefaultType

public static final String    getDefaultType()

Returns the default keystore type as specified in the Java security properties file, or the string "jks" (acronym for "Java keystore") if no such property exists. The Java security properties file is located in the file named <JAVA_HOME>/lib/security/java.security, where <JAVA_HOME> refers to the directory where the JDK was installed.

The default keystore type can be used by applications that do not want to use a hard-coded keystore type when calling one of the getInstance methods, and want to provide a default keystore type in case a user does not specify its own.

The default keystore type can be changed by setting the value of the "keystore.type" security property (in the Java security properties file) to the desired keystore type.

Returns:

the default keystore type as specified in the Java security properties file, or the string "jks" if no such property exists.

getProvider

public final Provider    getProvider()

Returns the provider of this keystore.

Returns:

the provider of this keystore.

getType

public final String    getType()

Returns the type of this keystore.

Returns:

the type of this keystore.

getKey

public final Key    getKey(String    alias,
                        char[] password)
                 throws KeyStoreException   ,
                        NoSuchAlgorithmException   ,
                        UnrecoverableKeyException   

Returns the key associated with the given alias, using the given password to recover it. The key must have been associated with the alias by a call to setKeyEntry, or by a call to setEntry with a PrivateKeyEntry or SecretKeyEntry.

Parameters:

alias - the alias name

password - the password for recovering the key

Returns:

the requested key, or null if the given alias does not exist or does not identify a key-related entry.

Throws:

KeyStoreException - if the keystore has not been initialized (loaded).

NoSuchAlgorithmException - if the algorithm for recovering the key cannot be found

UnrecoverableKeyException - if the key cannot be recovered (e.g., the given password is wrong).

getCertificateChain

public final Certificate   [] getCertificateChain(String    alias)
                                        throws KeyStoreException   

Returns the certificate chain associated with the given alias. The certificate chain must have been associated with the alias by a call to setKeyEntry, or by a call to setEntry with a PrivateKeyEntry.

Parameters:

alias - the alias name

Returns:

the certificate chain (ordered with the user's certificate first and the root certificate authority last), or null if the given alias does not exist or does not contain a certificate chain

Throws:

KeyStoreException - if the keystore has not been initialized (loaded).

getCertificate