File	Doc	Category	Size	Date	Package
RsaShaSig.java	API Doc	phoneME MR2 API (J2ME)	6172	Wed May 02 18:00:00 BST 2007	com.sun.midp.crypto

RsaShaSig

• java.lang.Object
  • Signature

Fields Summary
private static final byte[]	PREFIX_SHA1 Expected prefix in decrypted value when SHA-1 hash is used with RSA signing. This prefix is followed by the SHA hash.
RSASig	rsaSig Common signature class.

Constructors Summary
public RsaShaSig() Constructs an RSA signature object that uses SHA1 as message digest algorithm. exception RuntimeException if SHA-1 is not available try { rsaSig = new RSASig(PREFIX_SHA1, MessageDigest.getInstance("SHA-1")); } catch (NoSuchAlgorithmException e) { throw new RuntimeException("Needed algorithm not available"); }

Methods Summary
public java.lang.String	getAlgorithm() Gets the signature algorithm. return the algorithmimplemented by this signature object return "SHA1withRSA";
public int	getLength() Gets the byte-length of the signature. return the byte-length of the signature produced by this object return rsaSig.getLength();
public void	initSign(PrivateKey theKey) Initializes the RSASig object with the appropriate Key for signature creation. param theKey the key object to use for signing exception InvalidKeyException if the key type is inconsistent with the mode or signature implementation. rsaSig.initSign(theKey);
public void	initVerify(PublicKey theKey) Initializes the RSASig object with the appropriate Key for signature verification. param theKey the key object to use for verification exception InvalidKeyException if the key type is inconsistent with the mode or signature implementation. rsaSig.initVerify(theKey);
public int	sign(byte[] sigBuf, int sigOff, int sigLen) Generates the signature of all/last input data. A call to this method also resets this signature object to the state it was in when previously initialized via a call to init(). That is, the object is reset and available to sign another message. param sigBuf the output buffer to store signature data param sigOff starting offset within the output buffer at which to begin signature data param sigLen max length the signature can be return number of bytes of signature output in sigBuf exception SignatureException if the signature algorithm does not pad the message and the message is not block aligned return rsaSig.sign(sigBuf, sigOff, sigLen);
public void	update(byte[] inBuf, int inOff, int inLen) Accumulates a signature of the input data. When this method is used, temporary storage of intermediate results is required. This method should only be used if all the input data required for the signature is not available in one byte array. The sign() or verify() method is recommended whenever possible. param inBuf the input buffer of data to be signed param inOff starting offset within the input buffer for data to be signed param inLen the byte length of data to be signed exception SignatureException if the signature algorithm does not pad the message and the message is not block aligned see #verify(byte[], int, int, byte[], int, short) rsaSig.update(inBuf, inOff, inLen);
public boolean	verify(byte[] sigBuf, int sigOff, int sigLen) Verifies the signature of all/last input data against the passed in signature. A call to this method also resets this signature object to the state it was in when previously initialized via a call to init(). That is, the object is reset and available to verify another message. param sigBuf the input buffer containing signature data param sigOff starting offset within the sigBuf where signature data begins param sigLen byte length of signature data return true if signature verifies, false otherwise exception SignatureException if the signature algorithm does not pad the message and the message is not block aligned return rsaSig.verify(sigBuf, sigOff, sigLen);