diff --git a/src/main/java/top/gtb520/java/gnu/java/utils/library/utils/file/Encryption.java b/src/main/java/top/gtb520/java/gnu/java/utils/library/utils/file/Encryption.java deleted file mode 100644 index 202bf9a..0000000 --- a/src/main/java/top/gtb520/java/gnu/java/utils/library/utils/file/Encryption.java +++ /dev/null @@ -1,15 +0,0 @@ -package top.gtb520.java.gnu.java.utils.library.utils.file; - -import java.io.File; - -public class Encryption { - /*** - * 文件加密 - * - * @param file 文件 - * @param type 加密类型 - */ - public static void EncryptionFile(File file, String type) { - - } -} diff --git a/src/main/java/top/gtb520/java/gnu/java/utils/library/utils/file/EncryptionAndDecryption.java b/src/main/java/top/gtb520/java/gnu/java/utils/library/utils/file/EncryptionAndDecryption.java new file mode 100644 index 0000000..9073c80 --- /dev/null +++ b/src/main/java/top/gtb520/java/gnu/java/utils/library/utils/file/EncryptionAndDecryption.java @@ -0,0 +1,198 @@ +package top.gtb520.java.gnu.java.utils.library.utils.file; + +import java.io.File; +import java.io.OutputStream; +import java.nio.file.Files; +import java.nio.file.StandardOpenOption; +import java.security.InvalidKeyException; +import java.security.NoSuchAlgorithmException; +import java.util.concurrent.CompletableFuture; + +import javax.crypto.BadPaddingException; +import javax.crypto.Cipher; +import javax.crypto.IllegalBlockSizeException; +import javax.crypto.KeyGenerator; +import javax.crypto.NoSuchPaddingException; +import javax.crypto.SecretKey; + +public class EncryptionAndDecryption { + /*** + * 文件加密 + * 异步执行加密操作 + * 加密后的文件保存为原文件名加 .enc 后缀，位于同目录下 + * + * @param file 文件 + * @param type 加密类型 + * @return 加密后的文件，失败时返回 null + */ + public static File EncryptionFile(File file, EncryptionType type) { + File TargetFile = null; + + if (file == null || !file.exists() || !file.isFile()) { + return null; + } + + try { + TargetFile = CompletableFuture.supplyAsync(() -> { + try { + // 读取原文件内容 + byte[] plainBytes = Files.readAllBytes(file.toPath()); + + // 根据加密类型生成对称密钥 + SecretKey secretKey = generateSecretKey(type); + byte[] encryptedBytes = encryptBytes(plainBytes, secretKey, type); + + // 写入加密后的文件，文件格式：[1字节密钥长度][密钥字节][加密数据] + byte[] keyBytes = secretKey.getEncoded(); + String encryptedFileName = file.getName() + ".enc"; + File encryptedFile = new File(file.getParentFile(), encryptedFileName); + try (OutputStream os = Files.newOutputStream(encryptedFile.toPath(), + StandardOpenOption.CREATE, StandardOpenOption.TRUNCATE_EXISTING)) { + os.write(keyBytes.length); + os.write(keyBytes); + os.write(encryptedBytes); + os.flush(); + } + return encryptedFile; + } catch (Exception e) { + return null; + } + }).get(); + } catch (Exception e) { + TargetFile = null; + } + + return TargetFile; + } + + /*** + * 生成对称密钥 + * + * @param type 加密类型 + * @return 对称密钥 + */ + private static SecretKey generateSecretKey(EncryptionType type) throws NoSuchAlgorithmException { + String algorithm = switch (type) { + case AES -> "AES"; + case DES -> "DES"; + case RSA -> "AES"; // RSA 为非对称加密，此处用 AES 做对称加密替代 + }; + KeyGenerator keyGen = KeyGenerator.getInstance(algorithm); + int keySize = switch (type) { + case AES -> 128; + case DES -> 56; + case RSA -> 128; + }; + keyGen.init(keySize); + return keyGen.generateKey(); + } + + /*** + * 对字节数据进行加密 + * + * @param data 原始数据 + * @param key 密钥 + * @param type 加密类型 + * @return 加密后的数据 + */ + private static byte[] encryptBytes(byte[] data, SecretKey key, EncryptionType type) + throws NoSuchAlgorithmException, NoSuchPaddingException, + InvalidKeyException, IllegalBlockSizeException, BadPaddingException { + String algorithm = switch (type) { + case AES -> "AES/ECB/PKCS5Padding"; + case DES -> "DES/ECB/PKCS5Padding"; + case RSA -> "AES/ECB/PKCS5Padding"; + }; + Cipher cipher = Cipher.getInstance(algorithm); + cipher.init(Cipher.ENCRYPT_MODE, key); + return cipher.doFinal(data); + } + + /*** + * 文件解密 + * 异步执行解密操作 + * 解密后的文件去除 .enc 后缀，保存在同目录下 + * + * @param file 加密文件（.enc） + * @param type 加密类型，须与加密时一致 + * @return 解密后的文件，失败时返回 null + */ + public static File DecryptionFile(File file, EncryptionType type) { + File TargetFile = null; + + if (file == null || !file.exists() || !file.isFile()) { + return null; + } + + try { + TargetFile = CompletableFuture.supplyAsync(() -> { + try { + byte[] fileBytes = Files.readAllBytes(file.toPath()); + + // 读取文件头中的密钥长度和密钥 + int keyLength = fileBytes[0] & 0xFF; + byte[] keyBytes = new byte[keyLength]; + System.arraycopy(fileBytes, 1, keyBytes, 0, keyLength); + + // 还原密钥 + String algorithm = switch (type) { + case AES -> "AES"; + case DES -> "DES"; + case RSA -> "AES"; + }; + SecretKey secretKey = new javax.crypto.spec.SecretKeySpec(keyBytes, algorithm); + + // 提取加密数据部分 + byte[] encryptedBytes = new byte[fileBytes.length - 1 - keyLength]; + System.arraycopy(fileBytes, 1 + keyLength, encryptedBytes, 0, encryptedBytes.length); + + byte[] decryptedBytes = decryptBytes(encryptedBytes, secretKey, type); + + // 生成解密后的文件名，去除 .enc 后缀 + String fileName = file.getName(); + String decryptedFileName = fileName.endsWith(".enc") + ? fileName.substring(0, fileName.length() - 4) + : fileName + ".dec"; + File decryptedFile = new File(file.getParentFile(), decryptedFileName); + try (OutputStream os = Files.newOutputStream(decryptedFile.toPath(), + StandardOpenOption.CREATE, StandardOpenOption.TRUNCATE_EXISTING)) { + os.write(decryptedBytes); + os.flush(); + } + return decryptedFile; + } catch (Exception e) { + return null; + } + }).get(); + } catch (Exception e) { + TargetFile = null; + } + + return TargetFile; + } + + /*** + * 对字节数据进行解密 + * + * @param data 加密数据 + * @param key 密钥 + * @param type 加密类型 + * @return 解密后的数据 + */ + private static byte[] decryptBytes(byte[] data, SecretKey key, EncryptionType type) + throws NoSuchAlgorithmException, NoSuchPaddingException, + InvalidKeyException, IllegalBlockSizeException, BadPaddingException { + String algorithm = switch (type) { + case AES -> "AES/ECB/PKCS5Padding"; + case DES -> "DES/ECB/PKCS5Padding"; + case RSA -> "AES/ECB/PKCS5Padding"; + }; + Cipher cipher = Cipher.getInstance(algorithm); + cipher.init(Cipher.DECRYPT_MODE, key); + return cipher.doFinal(data); + } + + public enum EncryptionType { + AES, DES, RSA; + } +}