MyDSASignature (anonlib 00.21.029-SNAPSHOT API)

java.lang.Object
- anon.crypto.MyDSASignature

All Implemented Interfaces:

IMySignature, ISignatureCreationAlgorithm, ISignatureVerificationAlgorithm
```
public final class MyDSASignature
extends java.lang.Object
implements IMySignature
```
Implements the DSA algorithm for signatures.

Constructor Summary

Constructors
Constructor and Description

MyDSASignature()
The key with that this algorithm has been initialised.

Constructors
Constructor and Description
`MyDSASignature()` The key with that this algorithm has been initialised.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`byte[]`	`decodeForXMLSignature(byte[] a_encodedSignature)` Tries to decode a signature in a way as it would meet the W3C standard for DSA XML signature values.
`byte[]`	`encodeForXMLSignature(byte[] a_signature)` Encodes a signature in a way it meets the W3C standard for DSA XML signature values.
`mybouncycastle.org.bouncycastle.asn1.x509.AlgorithmIdentifier`	`getIdentifier()` Returns the algorithm identifier (DSA with SHA1).
`java.lang.String`	`getXMLSignatureAlgorithmReference()` Returns http://www.w3.org/2000/09/xmldsig#dsa-sha1.
`void`	`initSign(IMyPrivateKey k)` Initialises the algorithm for signing.
`void`	`initVerify(IMyPublicKey k)` Initialises the algorithm for verifying.
`byte[]`	`sign(byte[] bytesToSign)` Signs a message and returns the signature.
`boolean`	`verify(byte[] a_message, byte[] a_signature)` Tests if the signature of a specified message is valid.
`boolean`	`verify(byte[] a_message, int message_offset, int message_len, byte[] a_signature, int signature_offset, int signature_len)` Tests if the signature of a specified message is valid.

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

- Constructor Detail
  - MyDSASignature
```
public MyDSASignature()
```
    The key with that this algorithm has been initialised.
- Method Detail
  - initVerify
```
public void initVerify(IMyPublicKey k)
                throws java.security.InvalidKeyException
```
    Description copied from interface: IMySignature
    
    Initialises the algorithm for verifying. This must be done before doing the verify operation. The general contract of this method is that it must check if the algorithm has previously been initialised with the given key. If yes the method does nothing to save resources.
    
    Specified by:
    
    initVerify in interface IMySignature
    
    Parameters:
    
    k - a public key
    
    Throws:
    
    java.security.InvalidKeyException - if the key is invalid
  - initSign
```
public void initSign(IMyPrivateKey k)
              throws java.security.InvalidKeyException
```
    Description copied from interface: IMySignature
    
    Initialises the algorithm for signing. This must be done before doing the sign operation. The general contract of this method is that it must check if the algorithm has previously been initialised with the given key. If yes the method does nothing to save resources.
    
    Specified by:
    
    initSign in interface IMySignature
    
    Parameters:
    
    k - a private key
    
    Throws:
    
    java.security.InvalidKeyException - if the key is invalid
  - verify
```
public boolean verify(byte[] a_message,
                      int message_offset,
                      int message_len,
                      byte[] a_signature,
                      int signature_offset,
                      int signature_len)
```
    Description copied from interface: ISignatureVerificationAlgorithm
    
    Tests if the signature of a specified message is valid.
    
    Specified by:
    
    verify in interface ISignatureVerificationAlgorithm
    
    Parameters:
    
    a_message - a message
    
    message_offset - start of message
    
    message_len - length of message
    
    a_signature - a signature
    
    signature_offset - start of signature
    
    signature_len - length of signature
    
    Returns:
    
    true if the signature of a specified message is valid; false otherwiese
  - verify
```
public boolean verify(byte[] a_message,
                      byte[] a_signature)
```
    Description copied from interface: IMySignature
    
    Tests if the signature of a specified message is valid.
    
    Specified by:
    
    verify in interface IMySignature
    
    Specified by:
    
    verify in interface ISignatureVerificationAlgorithm
    
    Parameters:
    
    a_message - a message
    
    a_signature - a signature
    
    Returns:
    
    true if the signature of a specified message is valid; false otherwiese
  - sign
```
public byte[] sign(byte[] bytesToSign)
```
    Description copied from interface: IMySignature
    
    Signs a message and returns the signature.
    
    Specified by:
    
    sign in interface IMySignature
    
    Specified by:
    
    sign in interface ISignatureCreationAlgorithm
    
    Parameters:
    
    bytesToSign - a message
    
    Returns:
    
    the signature that was created
  - getIdentifier
```
public mybouncycastle.org.bouncycastle.asn1.x509.AlgorithmIdentifier getIdentifier()
```
    Returns the algorithm identifier (DSA with SHA1).
    
    Specified by:
    
    getIdentifier in interface ISignatureCreationAlgorithm
    
    Specified by:
    
    getIdentifier in interface ISignatureVerificationAlgorithm
    
    Returns:
    
    the algorithm identifier (DSA with SHA1)
  - encodeForXMLSignature
```
public byte[] encodeForXMLSignature(byte[] a_signature)
```
    Encodes a signature in a way it meets the W3C standard for DSA XML signature values. Extracts the ASN.1 encoded values for r and s from a DER encoded byte array. ASN.1 Notation: sequence { integer r integer s } --> Der-Encoding byte 0x30 // Sequence byte 44 + x // len in bytes (x = {0|1|2} depending on r and s byte 0x02 // integer byte <= 21 // len of r (21: if first bit of r set, we need a leading 0 --> 20 + 1 bytes) byte[] ... // value of r (with leading zero if necessary) byte 0x02 // integer byte <= 21 // len of s (21: if first bit of s set, we need a leading 0 --> 20 + 1 bytes) byte[] ... // value of s (with leading zero if necessary)
    
    Specified by:
    
    encodeForXMLSignature in interface IMySignature
    
    Specified by:
    
    encodeForXMLSignature in interface ISignatureCreationAlgorithm
    
    Parameters:
    
    a_signature - an non-encoded signature in DER format
    
    Returns:
    
    the encoded signature in R-S-encoding or null if an error occured
    
    See Also:
    
    http://www.w3.org/TR/xmldsig-core/#sec-DSA
  - decodeForXMLSignature
```
public byte[] decodeForXMLSignature(byte[] a_encodedSignature)
```
    Tries to decode a signature in a way as it would meet the W3C standard for DSA XML signature values. Making DER-Encoding of r and s..... ASN.1 Notation: sequence { integer r integer s } HINT: Sun JDK 1.4.x needs a leading '0' in the binary representation of r (and s) if r[0]>0x7F or s[0]>0x7F --> Der-Encoding 0x30 //Sequence 44 + x // len in bytes (x = {0|1|2} depending on r and s (see above) 0x02 // integer 20 | 21 // len in bytes of r .... //value of r (with leading zero if necessary) 0x02 //integer 20 | 21 //len of s ... value of s (with leading zero if necessary)
    
    Specified by:
    
    decodeForXMLSignature in interface IMySignature
    
    Specified by:
    
    decodeForXMLSignature in interface ISignatureVerificationAlgorithm
    
    Parameters:
    
    a_encodedSignature - an encoded signature in R-S format
    
    Returns:
    
    the decoded signature in DER format or null if an error occured
    
    See Also:
    
    http://www.w3.org/TR/xmldsig-core/#sec-DSA
  - getXMLSignatureAlgorithmReference
```
public java.lang.String getXMLSignatureAlgorithmReference()
```
    Returns http://www.w3.org/2000/09/xmldsig#dsa-sha1.
    
    Specified by:
    
    getXMLSignatureAlgorithmReference in interface IMySignature
    
    Specified by:
    
    getXMLSignatureAlgorithmReference in interface ISignatureCreationAlgorithm
    
    Specified by:
    
    getXMLSignatureAlgorithmReference in interface ISignatureVerificationAlgorithm
    
    Returns:
    
    http://www.w3.org/2000/09/xmldsig#dsa-sha1
    
    See Also:
    
    http://www.w3.org/TR/xmldsig-core/#sec-AlgID

Class MyDSASignature

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

MyDSASignature

Method Detail

initVerify

initSign

verify

verify

sign

getIdentifier

encodeForXMLSignature

decodeForXMLSignature

getXMLSignatureAlgorithmReference