KeyGenerator (Javadocs [I2P+ 2.13.0+]

java.lang.Object
- net.i2p.crypto.KeyGenerator

```
public final class KeyGenerator
extends Object
```
Comprehensive key generation facility for I2P cryptographic operations. This class provides methods to generate various types of cryptographic keys used throughout the I2P network, including:
- Asymmetric key pairs (ElGamal, DSA, ECDSA, EdDSA, RSA)
- Symmetric session keys (AES)
- Key derivation and conversion utilities
Supports both legacy algorithms (DSA, ElGamal) and modern cryptographic schemes (EdDSA, ECDSA) with configurable parameters for security and performance optimization.

Constructor Summary
Constructors
Constructor and Description
KeyGenerator(I2PAppContext context)
Create a new KeyGenerator.

Constructors
Constructor and Description
`KeyGenerator(I2PAppContext context)` Create a new KeyGenerator.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`Object[]`	`generatePKIKeypair()` ElGamal only.
`SimpleDataStructure[]`	`generatePKIKeys()` ElGamal only.
`KeyPair`	`generatePKIKeys(EncType type)` Supports EncTypes
`SessionKey`	`generateSessionKey()` Generate a private 256 bit session key
`SessionKey`	`generateSessionKey(byte[] salt, byte[] passphrase)` PBE the passphrase with the salt.
`SessionKey`	`generateSessionKey(byte[] salt, byte[] passphrase, int rounds)` PBE the passphrase with the salt using specified rounds.
`Object[]`	`generateSigningKeypair()` Generate a pair of DSA keys, where index 0 is a SigningPublicKey, and index 1 is a SigningPrivateKey.
`SimpleDataStructure[]`	`generateSigningKeys()` DSA-SHA1 only.
`SimpleDataStructure[]`	`generateSigningKeys(SigType type)` Generic signature type, supports DSA, RSA, ECDSA, EdDSA
`int`	`getElGamalExponentSize()` Size of the ElGamal exponent in bits.
`static KeyGenerator`	`getInstance()` Get the global KeyGenerator instance.
`int`	`getPBERT()` Get current rounds for new encryptions.
`int`	`getPBERTLegacy()` Get legacy rounds for migration.
`static PublicKey`	`getPublicKey(PrivateKey priv)` Convert a PrivateKey to its corresponding PublicKey.
`static SigningPublicKey`	`getSigningPublicKey(SigningPrivateKey priv)` Convert a SigningPrivateKey to a SigningPublicKey.
`static void`	`main(String[] args)` Usage: KeyGenerator [sigtype...]
`boolean`	`useLongElGamalExponent()` Whether to use a long (2048-bit) ElGamal exponent.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - KeyGenerator
```
public KeyGenerator(I2PAppContext context)
```
    Create a new KeyGenerator.
    Parameters:
    context - the I2P app context
- Method Detail
  - generatePKIKeypair
```
public Object[] generatePKIKeypair()
```
    ElGamal only. Generate a pair of keys, where index 0 is a PublicKey, and index 1 is a PrivateKey
    Returns:
    pair of keys
  - generatePKIKeys
```
public SimpleDataStructure[] generatePKIKeys()
```
    ElGamal only. Same as generatePKIKeypair() but different return type.
    Returns:
    pair of keys
  - generatePKIKeys
```
public KeyPair generatePKIKeys(EncType type)
```
    Supports EncTypes
    Parameters:
    type - the encryption type
    Returns:
    the key pair
  - generateSessionKey
```
public SessionKey generateSessionKey()
```
    Generate a private 256 bit session key
    Returns:
    session key
  - generateSessionKey
```
public SessionKey generateSessionKey(byte[] salt,
                                     byte[] passphrase)
```
    PBE the passphrase with the salt. Warning - SLOW
    Parameters:
    salt - the salt
    passphrase - the passphrase
    Returns:
    the session key
  - generateSessionKey
```
public SessionKey generateSessionKey(byte[] salt,
                                     byte[] passphrase,
                                     int rounds)
```
    PBE the passphrase with the salt using specified rounds. Warning - SLOW
    Parameters:
    salt - 16 bytes
    passphrase - the password
    rounds - iteration count (1000 for legacy, 1000000 for current)
    Returns:
    derived key
  - generateSigningKeypair
```
public Object[] generateSigningKeypair()
```
    Generate a pair of DSA keys, where index 0 is a SigningPublicKey, and index 1 is a SigningPrivateKey. DSA-SHA1 only.
    Returns:
    pair of keys
  - generateSigningKeys
```
public SimpleDataStructure[] generateSigningKeys()
```
    DSA-SHA1 only. Same as above but different return type
    Returns:
    pair of keys
  - generateSigningKeys
```
public SimpleDataStructure[] generateSigningKeys(SigType type)
                                          throws GeneralSecurityException
```
    Generic signature type, supports DSA, RSA, ECDSA, EdDSA
    Parameters:
    type - the signature type
    Returns:
    the key pair
    Throws:
    GeneralSecurityException - if key generation fails
  - getElGamalExponentSize
```
public int getElGamalExponentSize()
```
    Size of the ElGamal exponent in bits.
    Returns:
    the size in bits
  - getInstance
```
public static KeyGenerator getInstance()
```
    Get the global KeyGenerator instance.
    Returns:
    the global instance
  - getPBERT
```
public int getPBERT()
```
    Get current rounds for new encryptions.
    Returns:
    1000000
  - getPBERTLegacy
```
public int getPBERTLegacy()
```
    Get legacy rounds for migration.
    Returns:
    1000
  - getPublicKey
```
public static PublicKey getPublicKey(PrivateKey priv)
```
    Convert a PrivateKey to its corresponding PublicKey. As of 0.9.38, supports EncTypes
    Parameters:
    priv - PrivateKey object
    Returns:
    the corresponding PublicKey object
    Throws:
    IllegalArgumentException - on bad key
  - getSigningPublicKey
```
public static SigningPublicKey getSigningPublicKey(SigningPrivateKey priv)
```
    Convert a SigningPrivateKey to a SigningPublicKey. As of 0.9.16, supports all key types.
    Parameters:
    priv - a SigningPrivateKey object
    Returns:
    a SigningPublicKey object
    Throws:
    IllegalArgumentException - on bad key or unknown type
  - main
```
public static void main(String[] args)
```
    Usage: KeyGenerator [sigtype...]
    Parameters:
    args - command line arguments
  - useLongElGamalExponent
```
public boolean useLongElGamalExponent()
```
    Whether to use a long (2048-bit) ElGamal exponent.
    Returns:
    true if using long exponent

Class KeyGenerator

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

KeyGenerator

Method Detail

generatePKIKeypair

generatePKIKeys

generatePKIKeys

generateSessionKey

generateSessionKey

generateSessionKey

generateSigningKeypair

generateSigningKeys

generateSigningKeys

getElGamalExponentSize

getInstance

getPBERT

getPBERTLegacy

getPublicKey

getSigningPublicKey

main

useLongElGamalExponent