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@allanfreitas

allanfreitas/Encryptor.java

Forked from hsanger/Encryptor.java
Created February 19, 2023 20:21
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  1. @hsanger hsanger created this gist Feb 20, 2017.
    161 changes: 161 additions & 0 deletions Encryptor.java
    View file
    Original file line number Diff line number Diff line change
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    import java.io.BufferedReader;
    import java.io.BufferedWriter;
    import java.io.File;
    import java.io.FileNotFoundException;
    import java.io.FileReader;
    import java.io.FileWriter;
    import java.io.IOException;
    import java.util.Arrays;
    import java.util.Scanner;

    import javax.crypto.Cipher;
    import javax.crypto.spec.IvParameterSpec;
    import javax.crypto.spec.SecretKeySpec;

    import org.apache.commons.codec.binary.Base64;

    public class Encryptor {

    public static void main(String[] args) throws Exception {
    String original = "Hello World!";
    System.out.println("Original: " + original);
    String encrypted = encrypt("abc123ghidef9123", "RandomInitVector", original);
    System.out.println("Encrypted: " + encrypted);
    System.out.println("Decrypted: " + decrypt("abc123ghidef9123", "RandomInitVector", encrypted));
    }

    public static void encryptFile(File f, String key, String iv) throws IOException {
    BufferedReader br = new BufferedReader(new FileReader(f));
    int i = 0;
    String line = null;
    while ((line = br.readLine()) != null) {
    i++;
    }
    String[] linesToEncrypt = new String[i];
    BufferedReader br1 = new BufferedReader(new FileReader(f));
    int i1 = 0;
    String line1 = null;
    while ((line1 = br1.readLine()) != null) {
    linesToEncrypt[i1] = line1;
    System.out.println("Processing line " + i1 + ": " + line1);
    i1++;
    }
    String[] encryptedLines = new String[i];
    Arrays.fill(encryptedLines, "");
    int i2 = 0;
    for(String line2 : linesToEncrypt) {
    System.out.println(line2);
    encryptedLines[i2] = encrypt(key, iv, line2);
    i2++;
    }
    f.delete();
    f.createNewFile();
    for(String line3 : encryptedLines) {
    BufferedWriter bw = null;
    FileWriter fw = null;
    try {
    String data = line3 + "\n";
    fw = new FileWriter(f.getAbsoluteFile(), true);
    bw = new BufferedWriter(fw);
    bw.write(data);
    } catch (IOException e) {
    e.printStackTrace();
    } finally {
    try {
    if (bw != null)
    bw.close();
    if (fw != null)
    fw.close();
    } catch (IOException ex) {
    ex.printStackTrace();
    }
    }
    }
    }

    public static void decryptFile(File f, String key, String iv) throws IOException {
    BufferedReader br = new BufferedReader(new FileReader(f));
    int i = 0;
    String line = null;
    while ((line = br.readLine()) != null) {
    i++;
    }
    String[] linesToDecrypt = new String[i];
    BufferedReader br1 = new BufferedReader(new FileReader(f));
    int i1 = 0;
    String line1 = null;
    while ((line1 = br1.readLine()) != null) {
    linesToDecrypt[i1] = line1;
    System.out.println("Processing line " + i1 + ": " + line1);
    i1++;
    }
    String[] decryptedLines = new String[i];
    Arrays.fill(decryptedLines, "");
    int i2 = 0;
    for(String line2 : linesToDecrypt) {
    System.out.println(line2);
    decryptedLines[i2] = decrypt(key, iv, line2);
    i2++;
    }
    f.delete();
    f.createNewFile();
    for(String line3 : decryptedLines) {
    BufferedWriter bw = null;
    FileWriter fw = null;
    try {
    String data = line3 + "\n";
    fw = new FileWriter(f.getAbsoluteFile(), true);
    bw = new BufferedWriter(fw);
    bw.write(data);
    } catch (IOException e) {
    e.printStackTrace();
    } finally {
    try {
    if (bw != null)
    bw.close();
    if (fw != null)
    fw.close();
    } catch (IOException ex) {
    ex.printStackTrace();
    }
    }
    }
    }

    public static String encrypt(String key, String initVector, String value) {
    try {
    IvParameterSpec iv = new IvParameterSpec(initVector.getBytes("UTF-8"));
    SecretKeySpec skeySpec = new SecretKeySpec(key.getBytes("UTF-8"), "AES");

    Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5PADDING");
    cipher.init(Cipher.ENCRYPT_MODE, skeySpec, iv);

    byte[] encrypted = cipher.doFinal(value.getBytes());

    return Base64.encodeBase64String(encrypted);
    } catch (Exception ex) {
    ex.printStackTrace();
    }

    return null;
    }

    public static String decrypt(String key, String initVector, String encrypted) {
    try {
    IvParameterSpec iv = new IvParameterSpec(initVector.getBytes("UTF-8"));
    SecretKeySpec skeySpec = new SecretKeySpec(key.getBytes("UTF-8"), "AES");

    Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5PADDING");
    cipher.init(Cipher.DECRYPT_MODE, skeySpec, iv);

    byte[] original = cipher.doFinal(Base64.decodeBase64(encrypted));

    return new String(original);
    } catch (Exception ex) {
    ex.printStackTrace();
    }

    return null;
    }

    }