Package net.i2p.crypto

Class HKDF

java.lang.Object

net.i2p.crypto.HKDF

public final class HKDF
extends Object

Various flavors of HKDF using HMAC-SHA256. See RFC 5869. One or two outputs, with or without "info". All keys and outputs are exactly 32 bytes.

Since:

0.9.38

Constructor Summary

Constructors

Constructor	Description
HKDF(I2PAppContext context)	Thread safe, no state, can be reused

Method Summary

Modifier and Type	Method	Description
void	calculate(byte[] key, byte[] data, byte[] out)	One output, no info.
void	calculate(byte[] key, byte[] data, byte[] out, byte[] out2, int off2)	Two outputs, no info.
void	calculate(byte[] key, byte[] data, String info, byte[] out)	One output with info.
void	calculate(byte[] key, byte[] data, String info, byte[] out, byte[] out2, int off2)	Two outputs with info.

Methods inherited from class java.lang.Object

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

Constructor Detail

HKDF

public HKDF(I2PAppContext context)

Thread safe, no state, can be reused

Method Detail

calculate

public void calculate(byte[] key,
                      byte[] data,
                      byte[] out)

One output, no info.

Parameters:

key - first 32 bytes used as the key

out - must be exactly 32 bytes

calculate

public void calculate(byte[] key,
                      byte[] data,
                      String info,
                      byte[] out)

One output with info.

Parameters:

key - first 32 bytes used as the key

info - non-null ASCII, "" if none

out - must be exactly 32 bytes

calculate

public void calculate(byte[] key,
                      byte[] data,
                      byte[] out,
                      byte[] out2,
                      int off2)

Two outputs, no info.

Parameters:

key - first 32 bytes used as the key

out - 32 bytes will be copied to here

out2 - 32 bytes will be copied to here, may be the same as out

off2 - offset for copy to out2

calculate

public void calculate(byte[] key,
                      byte[] data,
                      String info,
                      byte[] out,
                      byte[] out2,
                      int off2)

Two outputs with info.

Parameters:

key - first 32 bytes used as the key

info - non-null ASCII, "" if none

out - 32 bytes will be copied to here

out2 - 32 bytes will be copied to here, may be the same as out

off2 - offset for copy to out2