坏消息是：恕我直言，该错误是由原生 Java 中 AES GCM 模式的错误实现引起的。即使您可以让它工作，您也会发现解密一个大文件（1 GB 左右）将花费大量时间（可能是几个小时？）。
但也有好消息：您可以/应该使用 BouncyCastle 作为解密任务的服务提供商 - 这样解密将起作用并且速度更快。
以下完整示例将创建一个 1 GB 大小的示例文件，使用 BouncyCastle 对其进行加密，然后对其进行解密。最后有一个文件比较显示明文和解密文件内容相等，文件将被删除。 您的设备上需要临时总共超过 3 GB 的可用空间才能运行此示例。
使用 64 KB 的缓冲区，我正在使用以下数据运行此示例：
加密毫秒数：14295 |解密：16249
1 KB 的缓冲区在加密方面有点慢，但在解密任务上要慢得多：
加密毫秒数：15250 |解密：21952
关于您的密码的最后一句话 - “AES/GCM/PKCS5Padding”在某些实现中不存在且“可用”，但实际使用的算法是“AES/GCM/NoPadding”（有关更多详细信息，请参阅Can PKCS5Padding be in AES/GCM mode?）。
import org.bouncycastle.jce.provider.BouncyCastleProvider;
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.spec.GCMParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.io.*;
import java.nio.file.Files;
import java.security.*;
import java.util.Arrays;
public class GcmTestBouncyCastle {
public static void main(String[] args) throws IOException, NoSuchPaddingException, InvalidAlgorithmParameterException,
NoSuchAlgorithmException, IllegalBlockSizeException, BadPaddingException, NoSuchProviderException, InvalidKeyException {
System.out.println("Encryption & Decryption with BouncyCastle AES-GCM-Mode");
System.out.println("https://stackoverflow.com/questions/61792534/out-of-memory-exception-when-decrypt-large-file-using-cipher");
// you need bouncy castle, get version 1.65 here:
// https://mvnrepository.com/artifact/org.bouncycastle/bcprov-jdk15on/1.65
Security.addProvider(new BouncyCastleProvider());
// setup files
// filenames
String filenamePlain = "plain.dat";
String filenameEncrypt = "encrypt.dat";
String filenameDecrypt = "decrypt.dat";
// generate a testfile of 1024 byte | 1 gb
//createFileWithDefinedLength(filenamePlain, 1024);
createFileWithDefinedLength(filenamePlain, 1024 * 1024 * 1024); // 1 gb
// time measurement
long startMilli = 0;
long encryptionMilli = 0;
long decryptionMilli = 0;
// generate nonce/iv
int GCM_NONCE_LENGTH = 12; // for a nonce of 96 bit length
int GCM_TAG_LENGTH = 16;
int GCM_KEY_LENGTH = 32; // 32 = 256 bit keylength, 16 = 128 bit keylength
SecureRandom r = new SecureRandom();
byte[] nonce = new byte[GCM_NONCE_LENGTH];
r.nextBytes(nonce);
// key should be generated as random byte[]
byte[] key = new byte[GCM_KEY_LENGTH];
r.nextBytes(key);
// encrypt file
startMilli = System.currentTimeMillis();
encryptWithGcmBc(filenamePlain, filenameEncrypt, key, nonce, GCM_TAG_LENGTH);
encryptionMilli = System.currentTimeMillis() - startMilli;
startMilli = System.currentTimeMillis();
decryptWithGcmBc(filenameEncrypt, filenameDecrypt, key, nonce, GCM_TAG_LENGTH);
decryptionMilli = System.currentTimeMillis() - startMilli;
// check that plain and decrypted files are equal
System.out.println("SHA256-file compare " + filenamePlain + " | " + filenameDecrypt + " : "
+ Arrays.equals(sha256File(filenamePlain), sha256File(filenameDecrypt)));
System.out.println("Milliseconds for Encryption: " + encryptionMilli + " | Decryption: " + decryptionMilli);
// clean up with files
Files.deleteIfExists(new File(filenamePlain).toPath());
Files.deleteIfExists(new File(filenameEncrypt).toPath());
Files.deleteIfExists(new File(filenameDecrypt).toPath());
}
public static void encryptWithGcmBc(String filenamePlain, String filenameEnc, byte[] key, byte[] nonce, int gcm_tag_length)
throws IOException, NoSuchAlgorithmException, NoSuchPaddingException, InvalidKeyException,
InvalidAlgorithmParameterException, IllegalBlockSizeException, BadPaddingException, NoSuchProviderException {
Cipher cipher = Cipher.getInstance("AES/GCM/NoPadding", "BC");
SecretKeySpec keySpec = new SecretKeySpec(key, "AES");
GCMParameterSpec gcmSpec = new GCMParameterSpec(gcm_tag_length * 8, nonce);
cipher.init(Cipher.ENCRYPT_MODE, keySpec, gcmSpec);
try (FileInputStream fis = new FileInputStream(filenamePlain);
BufferedInputStream in = new BufferedInputStream(fis);
FileOutputStream out = new FileOutputStream(filenameEnc);
BufferedOutputStream bos = new BufferedOutputStream(out)) {
//byte[] ibuf = new byte[1024];
byte[] ibuf = new byte[0x10000]; // = 65536
int len;
while ((len = in.read(ibuf)) != -1) {
byte[] obuf = cipher.update(ibuf, 0, len);
if (obuf != null)
bos.write(obuf);
}
byte[] obuf = cipher.doFinal();
if (obuf != null)
bos.write(obuf);
}
}
public static void decryptWithGcmBc(String filenameEnc, String filenameDec, byte[] key, byte[] nonce, int gcm_tag_length)
throws IOException, NoSuchAlgorithmException, NoSuchPaddingException, InvalidKeyException,
InvalidAlgorithmParameterException, IllegalBlockSizeException, BadPaddingException, NoSuchProviderException {
try (FileInputStream in = new FileInputStream(filenameEnc);
FileOutputStream out = new FileOutputStream(filenameDec)) {
//byte[] ibuf = new byte[1024];
byte[] ibuf = new byte[0x10000]; // = 65536
int len;
Cipher cipher = Cipher.getInstance("AES/GCM/NoPadding", "BC");
SecretKeySpec keySpec = new SecretKeySpec(key, "AES");
GCMParameterSpec gcmSpec = new GCMParameterSpec(gcm_tag_length * 8, nonce);
cipher.init(Cipher.DECRYPT_MODE, keySpec, gcmSpec);
while ((len = in.read(ibuf)) != -1) {
byte[] obuf = cipher.update(ibuf, 0, len);
if (obuf != null)
out.write(obuf);
}
byte[] obuf = cipher.doFinal();
if (obuf != null)
out.write(obuf);
}
}
// just for creating a large file within seconds
private static void createFileWithDefinedLength(String filenameString, long sizeLong) throws IOException {
RandomAccessFile raf = new RandomAccessFile(filenameString, "rw");
try {
raf.setLength(sizeLong);
} finally {
raf.close();
}
}
// just for file comparing
public static byte[] sha256File(String filenameString) throws IOException, NoSuchAlgorithmException {
byte[] buffer = new byte[8192];
int count;
MessageDigest md = MessageDigest.getInstance("SHA-256");
BufferedInputStream bis = new BufferedInputStream(new FileInputStream(filenameString));
while ((count = bis.read(buffer)) > 0) {
md.update(buffer, 0, count);
}
bis.close();
return md.digest();
}
}