RC2ParameterSpec ("Entrust Authority Security Toolkit for the Java Platform")

java.lang.Object
- javax.crypto.spec.RC2ParameterSpec
- - com.entrust.toolkit.security.spec.RC2ParameterSpec

All Implemented Interfaces:

ASN1Type, java.security.spec.AlgorithmParameterSpec
```
public class RC2ParameterSpec
extends javax.crypto.spec.RC2ParameterSpec
implements ASN1Type, java.security.spec.AlgorithmParameterSpec
```
This class implements the RC2 Parameter structure as defined in RFC 2268.
It specifies the initialization vector (IV) and version, and is designed for use with RC2 symmetric block cipher implementations.
```
 RC2Parameter ::= SEQUENCE {
     version    INTEGER,         -- [1..1024]
     iv         OCTET STRING     -- 8 octets
 }
 
```
The version number, on the range [1..1024], specifies in a round-about manner the number of effective key bits to be used for the RC2 encryption/decryption. The correspondence between effective key bits and version number is as follows:
- 1. If the number of effective key bits(EKB) is in the range [1..255], then the version number is given from a translation table as Table[EKB], where Table[] is a 256-byte translation table. The translation table simply specifies a permutation on the numbers 1-255.
- 2. If the number of effective key bits(EKB) is in the range [256-1024], then the version number is simply EKB.
Since:

7.0

Constructor Summary

Constructors
Constructor and Description
`RC2ParameterSpec()` The default constructor.
`RC2ParameterSpec(ASN1Object obj)` Creates a new `RC2ParameterSpec` object from an `ASN1Object`.
`RC2ParameterSpec(int effectiveKeyBits, byte[] iv)` Creates a new `RC2ParameterSpec` object with the specified components.
`RC2ParameterSpec(int effectiveKeyBits, byte[] iv, int offset)` Creates a new `RC2ParameterSpec` object with the specified components.

Method Summary

Methods
Modifier and Type	Method and Description
`void`	`decode(ASN1Object obj)` Decodes a `RC2ParameterSpec` object from an `ASN1Object`.
`static int`	`effectiveKeyBitsToVersion(int effectiveKeyBits)` This is a utility method that provides a conversion from the number of effective key bits to a version number.
`int`	`getEffectiveKeyBits()` Returns the number of effective key bits.
`byte[]`	`getIV()` Returns a copy of the initialization vector (IV).
`void`	`setEffectiveKeyBits(int effectiveKeyBits)` Sets the number of effective key bits.
`void`	`setIV(byte[] iv, int offset)` Sets the initialization vector (IV) by copying 8 bytes of data from the byte array beginning at the specified offset.
`ASN1Object`	`toASN1Object()` Encodes this `RC2ParameterSpec` object as an `ASN1Object`.
`java.lang.String`	`toString()` Creates a text representation of the ASN.1 structure of this `RC2ParameterSpec` object.
`static int`	`versionToEffectiveKeyBits(int version)` This is a utility method that provides a conversion from a version number to the number of effective key bits.

Methods inherited from class javax.crypto.spec.RC2ParameterSpec
equals, hashCode

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

- Constructor Detail
  - RC2ParameterSpec
```
public RC2ParameterSpec()
```
    The default constructor.
    It creates a new RC2ParameterSpec object with default components; effective key bits of 32, and an empty or all-zero 8-byte initialization vector (IV).
  - RC2ParameterSpec
```
public RC2ParameterSpec(int effectiveKeyBits,
                byte[] iv)
```
    Creates a new RC2ParameterSpec object with the specified components.
    The first 8 bytes of the supplied byte array are copied, and used as the initialization vector (IV).
    
    Parameters:
    effectiveKeyBits - the number of effective key bits
    iv - a byte array containing the initialization vector
    
    Throws:
    
    java.lang.IllegalArgumentException - thrown if the byte array is null, or if the number of effective key bits is not in the allowed range of [1..1024]
    
    java.lang.ArrayIndexOutOfBoundsException - thrown if an 8-byte initialization vector could not be extracted from the byte array
  - RC2ParameterSpec
```
public RC2ParameterSpec(int effectiveKeyBits,
                byte[] iv,
                int offset)
```
    Creates a new RC2ParameterSpec object with the specified components.
    The 8-byte initialization vector (IV) is copied from the supplied byte array starting at the indicated offset.
    
    Parameters:
    effectiveKeyBits - the number of effective key bits
    iv - a byte array containing the initialization vector
    offset - the offset in the byte array where the initialization vector begins
    
    Throws:
    
    java.lang.IllegalArgumentException - thrown if the byte array is null, or if the number of effective key bits is not in the allowed range of [1..1024]
    
    java.lang.ArrayIndexOutOfBoundsException - thrown if an 8-byte initialization vector could not be extracted from the byte array
  - RC2ParameterSpec
```
public RC2ParameterSpec(ASN1Object obj)
                 throws CodingException
```
    Creates a new RC2ParameterSpec object from an ASN1Object.
    The ASN1Object must be a RC2Parameter structure.
    
    Parameters:
    obj - the ASN.1 representation of a RC2Parameter structure
    
    Throws:
    
    CodingException - thrown if an errors occurs while decoding the ANS1Object
- Method Detail
  - effectiveKeyBitsToVersion
```
public static int effectiveKeyBitsToVersion(int effectiveKeyBits)
```
    This is a utility method that provides a conversion from the number of effective key bits to a version number.
    The version number is only used during the ASN.1 encoding/deocding of an RC2Parameter is not used by the RC2 symmetric block cipher. This conversion is automatically done during a call to toASN1Object() to set the version number in the ASN.1 structure.
    
    The version number, on the range [1..1024], specifies in a round-about manner the number of effective key bits to be used for the RC2 encryption/decryption. The correspondence between effective key bits and version number is as follows:
    - 1. If the number of effective key bits(EKB) is in the range [1..255], then the version number is given from a translation table as Table[EKB], where Table[] is a 256-byte translation table. The translation table simply specifies a permutation on the numbers 0-255.
    - 2. If the number of effective key bits(EKB) is in the range [256-1024], then the version number is simply EKB.
    Parameters:
    effectiveKeyBits - the number of effective key bits
    
    Returns:
    the version number
    
    Throws:
    
    java.lang.IllegalArgumentException - thrown if number of effective key bits is not in the allowed range of [1..1024]
  - versionToEffectiveKeyBits
```
public static int versionToEffectiveKeyBits(int version)
```
    This is a utility method that provides a conversion from a version number to the number of effective key bits.
    The version number is only used during the ASN.1 encoding/deocding of an RC2Parameter is not used by the RC2 symmetric block cipher. This conversion is automatically done during a call to decode(ASN1Object) to retrieve the number of effective key bits from the ASN.1 structure.
    The version number, on the range [1..1024], specifies in a round-about manner the number of effective key bits to be used for the RC2 encryption/decryption. The correspondence between effective key bits and version number is as follows:
    - 1. If the number of effective key bits(EKB) is in the range [1..255], then the version number is given from a translation table as Table[EKB], where Table[] is a 256-byte translation table. The translation table simply specifies a permutation on the numbers 0-255.
    - 2. If the number of effective key bits(EKB) is in the range [256-1024], then the version number is simply EKB.
    Parameters:
    version - the version number
    
    Returns:
    the number of effective key bits
    
    Throws:
    
    java.lang.IllegalArgumentException - thrown if version number is not in the allowed range of [1..1024]
  - getEffectiveKeyBits
```
public int getEffectiveKeyBits()
```
    Returns the number of effective key bits.
    
    Overrides:
    
    getEffectiveKeyBits in class javax.crypto.spec.RC2ParameterSpec
    
    Returns:
    the number of effective key bits
  - getIV
```
public byte[] getIV()
```
    Returns a copy of the initialization vector (IV).
    
    Overrides:
    
    getIV in class javax.crypto.spec.RC2ParameterSpec
    
    Returns:
    a copy of the initialization vector
  - setEffectiveKeyBits
```
public void setEffectiveKeyBits(int effectiveKeyBits)
```
    Sets the number of effective key bits.
    
    Parameters:
    effectiveKeyBits - the number of effective key bits
    
    Throws:
    
    java.lang.IllegalArgumentException - thrown if the number of effective key bits is not in the allowed range of [1..1024]
  - setIV
```
public void setIV(byte[] iv,
         int offset)
```
    Sets the initialization vector (IV) by copying 8 bytes of data from the byte array beginning at the specified offset.
    
    Parameters:
    iv - a byte array containing the initialization vector
    offset - the offset in the byte array where the initialization vector begins
    
    Throws:
    
    java.lang.ArrayIndexOutOfBoundsException - thrown if an 8-byte initialization vector could not be extracted from the byte array
  - decode
```
public void decode(ASN1Object obj)
            throws CodingException
```
    Decodes a RC2ParameterSpec object from an ASN1Object.
    The ASN1Object must be a RC2Parameter structure.
    
    This method internally performs the version to effective key bit transform, so that the effective key bit length is set properly.
    
    Specified by:
    
    decode in interface ASN1Type
    
    Parameters:
    obj - an ASN.1 representation of a RC2Parameter structure
    
    Throws:
    
    CodingException - thrown if an errors occurs while decoding the ANS1Object
  - toASN1Object
```
public ASN1Object toASN1Object()
```
    Encodes this RC2ParameterSpec object as an ASN1Object.
    This method internally performs the effective key bit to version transform, so that the version (and not the effective key bit length) is included in the ASN1 structure.
    
    Specified by:
    
    toASN1Object in interface ASN1Type
    
    Returns:
    an ASN.1 representation of the RC2Parameter structure
  - toString
```
public java.lang.String toString()
```
    Creates a text representation of the ASN.1 structure of this RC2ParameterSpec object.
    
    Overrides:
    
    toString in class java.lang.Object
    
    Returns:
    a text representation of the ASN.1 structure of this object

Class RC2ParameterSpec

Constructor Summary

Method Summary

Methods inherited from class javax.crypto.spec.RC2ParameterSpec

Methods inherited from class java.lang.Object

Constructor Detail

RC2ParameterSpec

RC2ParameterSpec

RC2ParameterSpec

RC2ParameterSpec

Method Detail

effectiveKeyBitsToVersion

versionToEffectiveKeyBits

getEffectiveKeyBits

getIV

setEffectiveKeyBits

setIV

decode

toASN1Object

toString