com.dalsemi.system
Class Security
java.lang.Object
|
+--com.dalsemi.system.Security
- public class Security
- extends java.lang.Object
A SHA-1 Hash and a "Better than Java" random number generator.
Method Summary |
static int |
getRandom()
Return a 32 bit random number from the system
random number generator. |
static byte[] |
hashMessage(byte[] message)
Computes a SHA-1 hash on the given message. |
static void |
hashMessage(byte[] msg,
int msgoffs,
int msglen,
byte[] hash,
int hashoffs,
byte[] buffer)
Computes a SHA-1 hash on the given message. |
Methods inherited from class java.lang.Object |
clone,
equals,
finalize,
getClass,
hashCode,
notify,
notifyAll,
toString,
wait,
wait,
wait |
getRandom
public static int getRandom()
- Return a 32 bit random number from the system
random number generator. This value is constructed
from four calls into the system generator each which
returns a byte. Each byte is the LSB of a 16
bit LFSR which is mixed using XOR with
clock/timer values from throughout the sytem.
This is definitely not cryptographically secure,
but it's better than pure pseudo random.
- Returns:
- one 32 bit pseudorandom doubleplusgood number
hashMessage
public static byte[] hashMessage(byte[] message)
- Computes a SHA-1 hash on the given message.
See FIPS 180-1 for more information on SHA-1.
- Parameters:
message
- the message to hash- Returns:
- the result of the hash (20 bytes)
hashMessage
public static void hashMessage(byte[] msg,
int msgoffs,
int msglen,
byte[] hash,
int hashoffs,
byte[] buffer)
- Computes a SHA-1 hash on the given message.
See FIPS 180-1 for more information on SHA-1.
- Parameters:
msg
- the message to hashmsgoffs
- offset into the message arraymsglen
- length of the message to hashhash
- holds the hash value on return (20 bytes minimum)hashoffs
- offset into the hash value arraybuffer
- buffer for SHA-1 calculation (320 bytes minimum)
Also see:
o TINI 1.16 API, Optional Modules
o TINI Home Page
o 1-Wire API
o JDK 1.1
Last update Wed Jun 8 17:19:36 CDT 2005