Signature Test Program Result

JDK Tutorials - Herong's Tutorial Examples - Version 6.02, by Dr. Herong Yang

JDK Tutorials - Herong's Tutorial Examples

∟Digital Signature Algorithm and Sample Program

∟Signature Test Program Result

This section provides test result of JcaSignatureTest.java with SHA1withDSA and SHA1withRSA digital signature algorithms.

Here is the result of my first test of JcaSignatureTest.java with the SHA1withDSA algorithm. It was done with JDK 1.8.

>javac -classpath . JcaSignatureTest.java

>java -cp . JcaSignatureTest JcaSignatureTest.class 
   sign.dsa DSA SHA1withDSA

Signature Object Info:
Algorithm = SHA1withDSA
Provider = SUN version 1.8

Sign Processing Info:
Number of input bytes = 4022
Number of output bytes = 47

Signature Object Info:
Algorithm = SHA1withDSA
Provider = SUN version 1.8
Verify Processing Info:
Number of input bytes = 4022
Verification result = true

>java HexWriter sign.dsa sign_dsa.hex

type sign_dsa.hex
302D02141DE6EF6B92A5A2539D10B190
DE3910C8FB9AD27B02150084B5D4EB2A
1079FFD20BEA187C842F954169B243

The program seems to be working:

A pair of keys is generated using the DSA algorithm first.
Then a signature is generated for input file, JcaSignatureTest.class, using the SHA1withDSA algorithm, which uses SHA-1 for the message digest generation, and DSA for encryption.
Finally, the signature is verified with the public key and the result shows that the signature is valid.

Of course, you can choose other combinations of different key pair generation algorithms and message digest algorithms. For example, SHA1withRSA:

>java -cp . JcaSignatureTest JcaSignatureTest.class 
   sign.rsa RSA SHA1withRSA

Signature Object Info:
Algorithm = SHA1withRSA
Provider = SunRsaSign version 1.8

Sign Processing Info:
Number of input bytes = 4022
Number of output bytes = 64

Signature Object Info:
Algorithm = SHA1withRSA
Provider = SunRsaSign version 1.8
Verify Processing Info:
Number of input bytes = 4022
Verification result = true

>java -cp . JcaSignatureTest JcaSignatureTest.class 
   sign_2.rsa RSA MD5withRSA

Signature Object Info:
Algorithm = MD5withRSA
Provider = SunRsaSign version 1.8

Sign Processing Info:
Number of input bytes = 4022
Number of output bytes = 64

Signature Object Info:
Algorithm = MD5withRSA
Provider = SunRsaSign version 1.8
Verify Processing Info:
Number of input bytes = 4022
Verification result = true

>java -cp . JcaSignatureTest JcaSignatureTest.class 
   sign_3.rsa RSA MD2withRSA

Signature Object Info:
Algorithm = MD2withRSA
Provider = SunRsaSign version 1.8

Sign Processing Info:
Number of input bytes = 4022
Number of output bytes = 64

Signature Object Info:
Algorithm = MD2withRSA
Provider = SunRsaSign version 1.8
Verify Processing Info:
Number of input bytes = 4022
Verification result = true

This sample program generates the signature and verifies the signature in single program. But in the real world, we must have at least two programs, one to be used by the sender of the date to generate the signature, and the other to be used by the receiver to verify the signature.

Last update: 2014.

Table of Contents

About This JDK Tutorial Book

Downloading and Installing JDK 1.8.0 on Windows

Downloading and Installing JDK 1.7.0 on Windows

Downloading and Installing JDK 1.6.2 on Windows

Java Date-Time API

Date, Time and Calendar Classes

Date and Time Object and String Conversion

Number Object and Numeric String Conversion

Locales, Localization Methods and Resource Bundles

Calling and Importing Classes Defined in Unnamed Packages