I2PHMac (I2P Anonymous Network - Java Documentation - Version 1.5.0)

java.lang.Object
- net.i2p.router.transport.udp.I2PHMac

```
class I2PHMac
extends Object
```
HMAC implementation based on RFC2104 H(K XOR opad, H(K XOR ipad, text)) modified by jrandom to use the session key byte array directly and to cache a frequently used buffer (called on doFinal). changes released into the public domain in 2005. This is renamed from HMac because the constructor HMac(digest, sz) does not exist in the standard bouncycastle library, thus it conflicts in JVMs that contain the standard library (Android). As of 0.9.12, refactored to use standard MessageDigest. Deprecated - Do not use outside of router or Syndie. Not a public API - Not for external use!

Since:

0.9.43 moved from org.bouncycastle.oldcrypto.macs

Constructor Summary

Constructors
Constructor Description

I2PHMac(MessageDigest digest)
Deprecated.
Use javax.crypto.Mac

I2PHMac(MessageDigest digest, int sz)

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`int`	`doFinal(byte[] out, int outOff)`
`String`	`getAlgorithmName()`
`int`	`getMacSize()`
`MessageDigest`	`getUnderlyingDigest()`
`void`	`init(byte[] key)`
`void`	`reset()`	Reset the mac generator.
`void`	`update(byte in)`
`void`	`update(byte[] in, int inOff, int len)`

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

Constructor Detail
- I2PHMac
```
@Deprecated
public I2PHMac(MessageDigest digest)
```
  Deprecated.
  Use javax.crypto.Mac
  
  Standard HMAC, size == digest size.
- I2PHMac
```
public I2PHMac(MessageDigest digest,
               int sz)
```
  Parameters:
  
  sz - override the digest's size, nonstandard if different. SEE NOTES in HMACGenerator about why this isn't compatible with standard HmacMD5

Method Detail

getAlgorithmName
```
public String getAlgorithmName()
```

getUnderlyingDigest

public MessageDigest getUnderlyingDigest()

init
```
public void init(byte[] key)
```

getMacSize
```
public int getMacSize()
```

update
```
public void update(byte in)
```

update

public void update(byte[] in,
                   int inOff,
                   int len)

doFinal

public int doFinal(byte[] out,
                   int outOff)

reset
```
public void reset()
```
Reset the mac generator.