Cryptography Tutorials - Herong's Tutorial Examples - Version 5.36, by Dr. Herong Yang
Testing RsaKeyEncryption.java with a 16-bit Key
This section provides a tutorial example on testing my RSA encryption and decryption implementation using the java.math.BigInteger class with a 16-bit key.
For the first test, I created a simple text file called, hello.text:
Hello world!
Then I generated a 16-bit RSA key:
C:\herong>java RsaKeyGeneration 16 > rsa_16.key C:\herong>type rsa_16.key p: 211 q: 223 m: 46620 Modulus: 47053 Key size: 16 Public key: 17837 Private key: 22373
Result of encryption and decryption is listed below:
C:\herong>java RsaKeyEncryption rsa_16.key hello.text hello.encrypted --- Reading public key --- Modulus: 47053 Key size: 16 Public key: 17837 Cleartext block size: 1 Ciphertext block size: 2 Encryption block count: 13 C:\herong>java RsaKeyDecryption rsa_16.key hello.encrypted hello.decrypted --- Reading private key --- Modulus: 47053 Key size: 16 Private key: 22373 Cleartext block size: 1 Ciphertext block size: 2 Decryption block count: 13 C:\herong>type hello.decrypted Hello world!
My RSA encryption and decryption implementation seems to be working. To confirm this, I tested it again with a binary file:
C:\herong>copy \windows\System32\xcopy.exe my_xcopy.exe
1 file(s) copied.
C:\herong>my_xcopy.exe
Invalid number of parameters
0 File(s) copied
C:\herong>java RsaKeyEncryption rsa_16.key
my_xcopy.exe my_xcopy_exe.encrypted
--- Reading public key ---
Modulus: 47053
Key size: 16
Public key: 17837
Cleartext block size: 1
Ciphertext block size: 2
Encryption block count: 36865
C:\herong>java RsaKeyDecryption rsa_16.key
my_xcopy_exe.encrypted my_xcopy_decrypted.exe
--- Reading private key ---
Modulus: 47053
Key size: 16
Private key: 22373
Cleartext block size: 1
Ciphertext block size: 2
Decryption block count: 36865
C:\herong>my_xcopy_decrypted.exe
Invalid number of parameters
0 File(s) copied
Looks very good. My RSA encryption and decryption implementation is working with my RSA 16-bit key.
Last update: 2013.
Table of Contents
Introduction to AES (Advanced Encryption Standard)
DES Algorithm - Illustrated with Java Programs
DES Algorithm Java Implementation
DES Algorithm - Java Implementation in JDK JCE
DES Encryption Operation Modes
PHP Implementation of DES - mcrypt
Blowfish - 8-Byte Block Cipher
Secret Key Generation and Management
Cipher - Secret Key Encryption and Decryption
►RSA Implementation using java.math.BigInteger Class
Generating Prime Number with BigInteger Class
Performance of Prime Number Generation
RSA Encryption Implementation using BigInteger Class
RsaKeyGenerator.java for RSA Key Generation
RSA Keys Generated by RsaKeyGenerator.java
RsaKeyValidator.java for RSA Key Validation
64-bit RSA Key Validated by RsaKeyValidator.java
Converting Byte Sequences to Positive Integers
Cleartext Block Size for RSA Encryption
Cleartext Message Padding and Revised Block Size
Ciphertext Block Size for RSA Encryption
RsaKeyEncryption.java for RSA Encryption Operation
RsaKeyDecryption.java for RSA Decryption Operation
►Testing RsaKeyEncryption.java with a 16-bit Key
Testing RsaKeyEncryption.java with a 64-bit Key
Testing RsaKeyEncryption.java with a 3072-bit Key
Introduction of DSA (Digital Signature Algorithm)
Java Default Implementation of DSA
Private key and Public Key Pair Generation
PKCS#8/X.509 Private/Public Encoding Standards
Cipher - Public Key Encryption and Decryption
OpenSSL Introduction and Installation
OpenSSL Generating and Managing RSA Keys
OpenSSL Generating and Signing CSR
OpenSSL Validating Certificate Path
"keytool" and "keystore" from JDK
"OpenSSL" Signing CSR Generated by "keytool"
Migrating Keys from "keystore" to "OpenSSL" Key Files
Certificate X.509 Standard and DER/PEM Formats
Migrating Keys from "OpenSSL" Key Files to "keystore"
Using Certificates in IE (Internet Explorer)