Fix formatting in Ciphers package (#2756)
This commit is contained in:
Yang Libin
GitHub
parent
0503c46680
commit
794719c773
@ -55,7 +55,9 @@ public class AES {
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0x8C, 0xA1, 0x89, 0x0D, 0xBF, 0xE6, 0x42, 0x68, 0x41, 0x99, 0x2D, 0x0F, 0xB0, 0x54, 0xBB, 0x16
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};
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/** Inverse Rijndael S-box Substitution table used for decryption in the subBytesDec step. */
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/**
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* Inverse Rijndael S-box Substitution table used for decryption in the subBytesDec step.
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*/
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private static final int[] INVERSE_SBOX = {
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0x52, 0x09, 0x6A, 0xD5, 0x30, 0x36, 0xA5, 0x38, 0xBF, 0x40, 0xA3, 0x9E, 0x81, 0xF3, 0xD7, 0xFB,
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0x7C, 0xE3, 0x39, 0x82, 0x9B, 0x2F, 0xFF, 0x87, 0x34, 0x8E, 0x43, 0x44, 0xC4, 0xDE, 0xE9, 0xCB,
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@ -1,13 +1,8 @@
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package Ciphers;
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import javax.crypto.*;
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import java.security.InvalidKeyException;
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import java.security.NoSuchAlgorithmException;
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import javax.crypto.BadPaddingException;
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import javax.crypto.Cipher;
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import javax.crypto.IllegalBlockSizeException;
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import javax.crypto.KeyGenerator;
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import javax.crypto.NoSuchPaddingException;
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import javax.crypto.SecretKey;
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/**
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* This example program shows how AES encryption and decryption can be done in Java. Please note
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@ -17,6 +12,7 @@ import javax.crypto.SecretKey;
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public class AESEncryption {
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private static final char[] HEX_ARRAY = "0123456789ABCDEF".toCharArray();
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/**
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* 1. Generate a plain text for encryption 2. Get a secret key (printed in hexadecimal form). In
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* actual use this must by encrypted and kept safe. The same key is required for decryption.
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@ -1,36 +1,23 @@
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//The ‘key’ for the Affine cipher consists of 2 numbers, we’ll call them a and b.
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// The following discussion assumes the use of a 26 character alphabet (m = 26).
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// a should be chosen to be relatively prime to m (i.e. a should have no factors in common with m).
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package Ciphers;
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import java.util.Scanner;
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class AffineCipher {
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class AffineCipher
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{
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static Scanner in = new Scanner(System.in);
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// Key values of a and b
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static int a = 17;
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static int b = 20;
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static String encryptMessage(char[] msg)
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{
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System.out.println("Enter key value a for encryption : ");
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int a = in.nextInt();
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System.out.println("Enter key value b for encryption : ");
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int b = in.nextInt();
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/// Initially empty cipher String
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static String encryptMessage(char[] msg) {
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/// Cipher Text initially empty
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String cipher = "";
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for (int i = 0; i < msg.length; i++)
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{
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for (int i = 0; i < msg.length; i++) {
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// Avoid space to be encrypted
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/* applying encryption formula ( a x + b ) mod m
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{here x is msg[i] and m is 26} and added 'A' to
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bring it in range of ascii alphabet[ 65-90 | A-Z ] */
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if (msg[i] != ' ')
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{
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if (msg[i] != ' ') {
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cipher = cipher
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+ (char) ((((a * (msg[i] - 'A')) + b) % 26) + 'A');
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} else // append space character
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} else // else simply append space character
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{
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cipher += msg[i];
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}
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@ -38,42 +25,30 @@ class AffineCipher
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return cipher;
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}
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static String decryptCipher(String cipher)
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{
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System.out.println("Enter key value a for decryption : ");
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int a = in.nextInt();
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System.out.println("Enter key value b for decryption : ");
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int b = in.nextInt();
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static String decryptCipher(String cipher) {
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String msg = "";
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int a_inv = 0;
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int flag = 0;
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//Find a^-1 (the multiplicative inverse of a
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//in the group of integers modulo m.)
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for (int i = 0; i < 26; i++)
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{
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for (int i = 0; i < 26; i++) {
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flag = (a * i) % 26;
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// Check if (a*i)%26 == 1,
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// if so, then i will be the multiplicative inverse of a
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if (flag == 1)
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{
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// then i will be the multiplicative inverse of a
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if (flag == 1) {
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a_inv = i;
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}
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}
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for (int i = 0; i < cipher.length(); i++)
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{
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for (int i = 0; i < cipher.length(); i++) {
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/*Applying decryption formula a^-1 ( x - b ) mod m
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{here x is cipher[i] and m is 26} and added 'A'
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to bring it in range of ASCII alphabet[ 65-90 | A-Z ] */
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if (cipher.charAt(i) != ' ')
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{
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if (cipher.charAt(i) != ' ') {
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msg = msg + (char) (((a_inv *
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((cipher.charAt(i) + 'A' - b)) % 26)) + 'A');
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}
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else // append space character
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} else //else simply append space character
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{
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msg += cipher.charAt(i);
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}
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@ -82,17 +57,17 @@ class AffineCipher
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return msg;
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}
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// Main method
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public static void main(String[] args)
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{
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// Driver code
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public static void main(String[] args) {
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String msg = "AFFINE CIPHER";
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// Encrypting message
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// Calling encryption function
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String cipherText = encryptMessage(msg.toCharArray());
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System.out.println("Encrypted Message is : " + cipherText);
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// Decrypting message
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// Calling Decryption function
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System.out.println("Decrypted Message is: " + decryptCipher(cipherText));
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}
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}
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@ -114,7 +114,9 @@ public class ColumnarTranspositionCipher {
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}
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}
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/** @return charValues */
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/**
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* @return charValues
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*/
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private static Object[] findElements() {
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Object[] charValues = new Object[keyword.length()];
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for (int i = 0; i < charValues.length; i++) {
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@ -1,169 +1,162 @@
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package Ciphers;
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import java.util.*;
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import java.util.Scanner;
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/*
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* Java Implementation of Hill Cipher
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* Hill cipher is a polyalphabetic substitution cipher. Each letter is represented by a number belonging to the set Z26 where A=0 , B=1, ..... Z=25.
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* To encrypt a message, each block of n letters (since matrix size is n x n) is multiplied by an invertible n × n matrix, against modulus 26.
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* To decrypt the message, each block is multiplied by the inverse of the matrix used for encryption.
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* The cipher key and plaintext/ciphertext are user inputs.
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* @author Ojasva Jain
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*/
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* Java Implementation of Hill Cipher
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* Hill cipher is a polyalphabetic substitution cipher. Each letter is represented by a number belonging to the set Z26 where A=0 , B=1, ..... Z=25.
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* To encrypt a message, each block of n letters (since matrix size is n x n) is multiplied by an invertible n × n matrix, against modulus 26.
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* To decrypt the message, each block is multiplied by the inverse of the matrix used for encryption.
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* The cipher key and plaintext/ciphertext are user inputs.
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* @author Ojasva Jain
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*/
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public class HillCipher{
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static Scanner in = new Scanner (System.in);
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public class HillCipher {
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static Scanner in = new Scanner(System.in);
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/* Following function encrypts the message
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*/
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static void encrypt(String message)
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{
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/* Following function encrypts the message
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*/
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static void encrypt(String message) {
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message = message.toUpperCase();
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// Get key matrix
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System.out.println("Enter key matrix size");
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int n = in.nextInt();
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System.out.println("Enter Key/encryptionKey matrix ");
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int keyMatrix[][] = new int [n][n];
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for(int i=0;i<n;i++){
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for(int j=0;j<n;j++){
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int keyMatrix[][] = new int[n][n];
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for (int i = 0; i < n; i++) {
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for (int j = 0; j < n; j++) {
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keyMatrix[i][j] = in.nextInt();
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}
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}
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//check if det = 0
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if(determinant(keyMatrix,n)%26 == 0)
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{
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if (determinant(keyMatrix, n) % 26 == 0) {
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System.out.println("Invalid key, as determinant = 0. Program Terminated");
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return;
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}
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int [][]messageVector = new int[n][1];
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String CipherText="";
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int cipherMatrix [][] = new int [n][1];
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int[][] messageVector = new int[n][1];
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String CipherText = "";
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int cipherMatrix[][] = new int[n][1];
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int j = 0;
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while(j<message.length()){
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for (int i = 0; i < n; i++){
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if(j>=message.length()){ messageVector[i][0] = 23;}
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else
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messageVector[i][0] = (message.charAt(j))%65;
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while (j < message.length()) {
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for (int i = 0; i < n; i++) {
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if (j >= message.length()) {
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messageVector[i][0] = 23;
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} else
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messageVector[i][0] = (message.charAt(j)) % 65;
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System.out.println(messageVector[i][0]);
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j++;
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}
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int x, i;
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for (i = 0; i < n; i++)
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{
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for (i = 0; i < n; i++) {
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cipherMatrix[i][0] = 0;
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for (x = 0; x < n; x++)
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{
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for (x = 0; x < n; x++) {
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cipherMatrix[i][0] += keyMatrix[i][x] * messageVector[x][0];
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}
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System.out.println(cipherMatrix[i][0]);
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cipherMatrix[i][0] = cipherMatrix[i][0] % 26;
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}
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for (i = 0; i < n; i++)
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CipherText += (char)(cipherMatrix[i][0] + 65);
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}
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System.out.println("Ciphertext: "+ CipherText);
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}
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//Following function decrypts a message
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static void decrypt(String message)
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{
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CipherText += (char) (cipherMatrix[i][0] + 65);
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}
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System.out.println("Ciphertext: " + CipherText);
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}
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//Following function decrypts a message
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static void decrypt(String message) {
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message = message.toUpperCase();
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// Get key matrix
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System.out.println("Enter key matrix size");
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int n = in.nextInt();
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System.out.println("Enter inverseKey/decryptionKey matrix ");
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int keyMatrix[][] = new int [n][n];
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for(int i=0;i<n;i++){
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for(int j=0;j<n;j++){
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int keyMatrix[][] = new int[n][n];
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for (int i = 0; i < n; i++) {
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for (int j = 0; j < n; j++) {
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keyMatrix[i][j] = in.nextInt();
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}
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}
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//check if det = 0
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if(determinant(keyMatrix,n)%26 == 0)
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{
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if (determinant(keyMatrix, n) % 26 == 0) {
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System.out.println("Invalid key, as determinant = 0. Program Terminated");
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return;
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}
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//solving for the required plaintext message
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int [][]messageVector = new int[n][1];
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String PlainText="";
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int plainMatrix [][] = new int [n][1];
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int[][] messageVector = new int[n][1];
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String PlainText = "";
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int plainMatrix[][] = new int[n][1];
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int j = 0;
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while(j<message.length()){
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for (int i = 0; i < n; i++){
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if(j>=message.length()){ messageVector[i][0] = 23;}
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else
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messageVector[i][0] = (message.charAt(j))%65;
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while (j < message.length()) {
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for (int i = 0; i < n; i++) {
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if (j >= message.length()) {
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messageVector[i][0] = 23;
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} else
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messageVector[i][0] = (message.charAt(j)) % 65;
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System.out.println(messageVector[i][0]);
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j++;
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}
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int x, i;
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for (i = 0; i < n; i++)
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{
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for (i = 0; i < n; i++) {
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plainMatrix[i][0] = 0;
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for (x = 0; x < n; x++)
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{
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for (x = 0; x < n; x++) {
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plainMatrix[i][0] += keyMatrix[i][x] * messageVector[x][0];
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}
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plainMatrix[i][0] = plainMatrix[i][0] % 26;
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}
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for (i = 0; i < n; i++)
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PlainText += (char)(plainMatrix[i][0] + 65);
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PlainText += (char) (plainMatrix[i][0] + 65);
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}
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System.out.println("Plaintext: " + PlainText);
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}
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System.out.println("Plaintext: "+PlainText);
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}
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// Determinant calculator
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public static int determinant(int a[][], int n){
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// Determinant calculator
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public static int determinant(int a[][], int n) {
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int det = 0, sign = 1, p = 0, q = 0;
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if(n==1){
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if (n == 1) {
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det = a[0][0];
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}
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else{
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int b[][] = new int[n-1][n-1];
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for(int x = 0 ; x < n ; x++){
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p=0;q=0;
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for(int i = 1;i < n; i++){
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for(int j = 0; j < n;j++){
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if(j != x){
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} else {
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int b[][] = new int[n - 1][n - 1];
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for (int x = 0; x < n; x++) {
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p = 0;
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q = 0;
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for (int i = 1; i < n; i++) {
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for (int j = 0; j < n; j++) {
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if (j != x) {
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b[p][q++] = a[i][j];
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if(q % (n-1) == 0){
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if (q % (n - 1) == 0) {
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p++;
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q=0;
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q = 0;
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}
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}
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}
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}
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det = det + a[0][x] *determinant(b, n-1) * sign;
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det = det + a[0][x] * determinant(b, n - 1) * sign;
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sign = -sign;
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}
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}
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return det;
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}
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}
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// Function to implement Hill Cipher
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static void hillcipher(String message)
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{
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// Function to implement Hill Cipher
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static void hillcipher(String message) {
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message.toUpperCase();
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System.out.println("What do you want to process from the message?");
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System.out.println("Press 1: To Encrypt");
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System.out.println("Press 2: To Decrypt");
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short sc = in.nextShort();
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if(sc == 1)
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if (sc == 1)
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encrypt(message);
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else if(sc == 2)
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else if (sc == 2)
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decrypt(message);
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else
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System.out.println("Invalid input, program terminated.");
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}
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}
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// Driver code
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public static void main(String[] args)
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{
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// Driver code
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public static void main(String[] args) {
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// Get the message to be encrypted
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System.out.println("Enter message");
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String message = in.nextLine();
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@ -1,10 +1,12 @@
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package Ciphers;
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import javax.swing.*;
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import java.math.BigInteger;
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import java.security.SecureRandom;
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import javax.swing.JOptionPane;
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/** @author Nguyen Duy Tiep on 23-Oct-17. */
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/**
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* @author Nguyen Duy Tiep on 23-Oct-17.
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*/
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public final class RSA {
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public static void main(String[] args) {
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@ -1,18 +1,17 @@
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package ciphers;
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import java.util.*;
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import java.util.HashMap;
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import java.util.Map;
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/**
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*
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* The simple substitution cipher is a cipher that has been in use for many hundreds of years
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* (an excellent history is given in Simon Singhs 'the Code Book').
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* It basically consists of substituting every plaintext character for a different ciphertext character.
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* It differs from the Caesar cipher in that the cipher alphabet is not simply the alphabet shifted,
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* it is completely jumbled.
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*
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*/
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public class simpleSubCipher {
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public class SimpleSubCipher {
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/**
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* Encrypt text by replacing each element with its opposite character.
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@ -25,7 +24,7 @@ public class simpleSubCipher {
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String encoded = "";
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// This map is used to encode
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Map<Character,Character> cipherMap = new HashMap<Character,Character>();
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Map<Character, Character> cipherMap = new HashMap<>();
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char beginSmallLetter = 'a';
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char beginCapitalLetter = 'A';
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@ -34,13 +33,13 @@ public class simpleSubCipher {
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String cipherCapital = cipherSmall.toUpperCase();
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// To handle Small and Capital letters
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for(int i = 0; i < cipherSmall.length(); i++){
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cipherMap.put(beginSmallLetter++,cipherSmall.charAt(i));
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cipherMap.put(beginCapitalLetter++,cipherCapital.charAt(i));
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for (int i = 0; i < cipherSmall.length(); i++) {
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cipherMap.put(beginSmallLetter++, cipherSmall.charAt(i));
|
||||
cipherMap.put(beginCapitalLetter++, cipherCapital.charAt(i));
|
||||
}
|
||||
|
||||
for(int i = 0; i < message.length(); i++){
|
||||
if(Character.isAlphabetic(message.charAt(i)))
|
||||
for (int i = 0; i < message.length(); i++) {
|
||||
if (Character.isAlphabetic(message.charAt(i)))
|
||||
encoded += cipherMap.get(message.charAt(i));
|
||||
else
|
||||
encoded += message.charAt(i);
|
||||
@ -60,7 +59,7 @@ public class simpleSubCipher {
|
||||
String decoded = "";
|
||||
|
||||
|
||||
Map<Character,Character> cipherMap = new HashMap<Character,Character>();
|
||||
Map<Character, Character> cipherMap = new HashMap<Character, Character>();
|
||||
|
||||
char beginSmallLetter = 'a';
|
||||
char beginCapitalLetter = 'A';
|
||||
@ -68,13 +67,13 @@ public class simpleSubCipher {
|
||||
cipherSmall = cipherSmall.toLowerCase();
|
||||
String cipherCapital = cipherSmall.toUpperCase();
|
||||
|
||||
for(int i = 0; i < cipherSmall.length(); i++){
|
||||
cipherMap.put(cipherSmall.charAt(i),beginSmallLetter++);
|
||||
cipherMap.put(cipherCapital.charAt(i),beginCapitalLetter++);
|
||||
for (int i = 0; i < cipherSmall.length(); i++) {
|
||||
cipherMap.put(cipherSmall.charAt(i), beginSmallLetter++);
|
||||
cipherMap.put(cipherCapital.charAt(i), beginCapitalLetter++);
|
||||
}
|
||||
|
||||
for(int i = 0; i < encryptedMessage.length(); i++){
|
||||
if(Character.isAlphabetic(encryptedMessage.charAt(i)))
|
||||
for (int i = 0; i < encryptedMessage.length(); i++) {
|
||||
if (Character.isAlphabetic(encryptedMessage.charAt(i)))
|
||||
decoded += cipherMap.get(encryptedMessage.charAt(i));
|
||||
else
|
||||
decoded += encryptedMessage.charAt(i);
|
||||
@ -84,8 +83,8 @@ public class simpleSubCipher {
|
||||
}
|
||||
|
||||
public static void main(String[] args) {
|
||||
String a = encode("defend the east wall of the castle","phqgiumeaylnofdxjkrcvstzwb");
|
||||
String b = decode(a,"phqgiumeaylnofdxjkrcvstzwb");
|
||||
String a = encode("defend the east wall of the castle", "phqgiumeaylnofdxjkrcvstzwb");
|
||||
String b = decode(a, "phqgiumeaylnofdxjkrcvstzwb");
|
||||
System.out.println(b);
|
||||
}
|
||||
|
||||
@ -1,6 +1,7 @@
|
||||
package Ciphers;
|
||||
|
||||
import java.util.*;
|
||||
import java.util.HashMap;
|
||||
import java.util.Map;
|
||||
|
||||
/**
|
||||
* The simple substitution cipher is a cipher that has been in use for many hundreds of years (an
|
||||
@ -74,7 +75,9 @@ public class SimpleSubstitutionCipher {
|
||||
return decoded.toString();
|
||||
}
|
||||
|
||||
/** TODO remove main and make JUnit Testing */
|
||||
/**
|
||||
* TODO remove main and make JUnit Testing
|
||||
*/
|
||||
public static void main(String[] args) {
|
||||
String a = encode("defend the east wall of the castle", "phqgiumeaylnofdxjkrcvstzwb");
|
||||
String b = decode(a, "phqgiumeaylnofdxjkrcvstzwb");
|
||||
|
||||
@ -1,83 +0,0 @@
|
||||
package Ciphers;
|
||||
class affineCipher
|
||||
{
|
||||
|
||||
// Key values of a and b
|
||||
static int a = 17;
|
||||
static int b = 20;
|
||||
|
||||
static String encryptMessage(char[] msg)
|
||||
{
|
||||
/// Cipher Text initially empty
|
||||
String cipher = "";
|
||||
for (int i = 0; i < msg.length; i++)
|
||||
{
|
||||
// Avoid space to be encrypted
|
||||
/* applying encryption formula ( a x + b ) mod m
|
||||
{here x is msg[i] and m is 26} and added 'A' to
|
||||
bring it in range of ascii alphabet[ 65-90 | A-Z ] */
|
||||
if (msg[i] != ' ')
|
||||
{
|
||||
cipher = cipher
|
||||
+ (char) ((((a * (msg[i] - 'A')) + b) % 26) + 'A');
|
||||
} else // else simply append space character
|
||||
{
|
||||
cipher += msg[i];
|
||||
}
|
||||
}
|
||||
return cipher;
|
||||
}
|
||||
|
||||
static String decryptCipher(String cipher)
|
||||
{
|
||||
String msg = "";
|
||||
int a_inv = 0;
|
||||
int flag = 0;
|
||||
|
||||
//Find a^-1 (the multiplicative inverse of a
|
||||
//in the group of integers modulo m.)
|
||||
for (int i = 0; i < 26; i++)
|
||||
{
|
||||
flag = (a * i) % 26;
|
||||
|
||||
// Check if (a*i)%26 == 1,
|
||||
// then i will be the multiplicative inverse of a
|
||||
if (flag == 1)
|
||||
{
|
||||
a_inv = i;
|
||||
}
|
||||
}
|
||||
for (int i = 0; i < cipher.length(); i++)
|
||||
{
|
||||
/*Applying decryption formula a^-1 ( x - b ) mod m
|
||||
{here x is cipher[i] and m is 26} and added 'A'
|
||||
to bring it in range of ASCII alphabet[ 65-90 | A-Z ] */
|
||||
if (cipher.charAt(i) != ' ')
|
||||
{
|
||||
msg = msg + (char) (((a_inv *
|
||||
((cipher.charAt(i) + 'A' - b)) % 26)) + 'A');
|
||||
}
|
||||
else //else simply append space character
|
||||
{
|
||||
msg += cipher.charAt(i);
|
||||
}
|
||||
}
|
||||
|
||||
return msg;
|
||||
}
|
||||
|
||||
// Driver code
|
||||
public static void main(String[] args)
|
||||
{
|
||||
String msg = "AFFINE CIPHER";
|
||||
|
||||
// Calling encryption function
|
||||
String cipherText = encryptMessage(msg.toCharArray());
|
||||
System.out.println("Encrypted Message is : " + cipherText);
|
||||
|
||||
// Calling Decryption function
|
||||
System.out.println("Decrypted Message is: " + decryptCipher(cipherText));
|
||||
|
||||
}
|
||||
}
|
||||
|
||||
Loading…
Reference in New Issue
Block a user