我有两个使用 Thrift 进行交互的应用程序。他们共享相同的密钥，我需要加密他们的消息。使用对称算法（例如 AES）是有意义的，但我还没有找到任何库来执行此操作。所以我做了一个研究并看到了以下选项：
使用内置 SSL 支持
我可以使用内置的 SSL 支持，建立安全连接并使用我的密钥作为身份验证令牌。除了已有的密钥之外，它还需要安装证书，但除了检查从客户端接收到的密钥是否与本地存储的密钥相同之外，我不需要执行任何操作。
实施对称加密
到目前为止，有以下几种选择：
- Extend
TSocket并覆盖write() and read()方法并加密/解密其中的数据。小写入流量将会增加。例如，如果TBinaryProtocol写入 4 字节整数，加密状态下将占用 1 个块（16 字节）。
- Extend
TSocket并包裹InputStream and OutputStream with CipherInputStream and CipherOutputStream. CipherOutputStream不会立即加密小字节数组，更新Cipher跟他们。当我们有足够的数据后，它们将被加密并写入底层OutputStream。所以它会等到你添加 4 个 4 字节整数并加密它们。它允许我们不浪费流量，但也是问题的一个原因 - 如果最后一个值不能填充块，它将永远不会被加密并写入底层流。它希望我写入可被其块大小（16 字节）整除的字节数，但我不能使用TBinaryProtocol.
- 重新实施
TBinaryProtocol，缓存所有写入，而不是将它们写入流并加密writeMessageEnd()方法。实现解密readMessageBegin()。我认为加密应该在传输层而不是协议层进行。
请与我分享您的想法。
UPDATE
TFramedTransport 之上的 Java 实现
TEncryptedFramedTransport.java
package tutorial;
import org.apache.thrift.TByteArrayOutputStream;
import org.apache.thrift.transport.TMemoryInputTransport;
import org.apache.thrift.transport.TTransport;
import org.apache.thrift.transport.TTransportException;
import org.apache.thrift.transport.TTransportFactory;
import javax.crypto.Cipher;
import java.security.Key;
/**
* TEncryptedFramedTransport is a buffered TTransport. It encrypts fully read message
* with the "AES/ECB/PKCS5Padding" symmetric algorithm and send it, preceeding with a 4-byte frame size.
*/
public class TEncryptedFramedTransport extends TTransport {
public static final String ALGORITHM = "AES/ECB/PKCS5Padding";
private Cipher encryptingCipher;
private Cipher decryptingCipher;
protected static final int DEFAULT_MAX_LENGTH = 0x7FFFFFFF;
private int maxLength_;
private TTransport transport_ = null;
private final TByteArrayOutputStream writeBuffer_ = new TByteArrayOutputStream(1024);
private TMemoryInputTransport readBuffer_ = new TMemoryInputTransport(new byte[0]);
public static class Factory extends TTransportFactory {
private int maxLength_;
private Key secretKey_;
public Factory(Key secretKey) {
this(secretKey, DEFAULT_MAX_LENGTH);
}
public Factory(Key secretKey, int maxLength) {
maxLength_ = maxLength;
secretKey_ = secretKey;
}
@Override
public TTransport getTransport(TTransport base) {
return new TEncryptedFramedTransport(base, secretKey_, maxLength_);
}
}
/**
* Constructor wraps around another tranpsort
*/
public TEncryptedFramedTransport(TTransport transport, Key secretKey, int maxLength) {
transport_ = transport;
maxLength_ = maxLength;
try {
encryptingCipher = Cipher.getInstance(ALGORITHM);
encryptingCipher.init(Cipher.ENCRYPT_MODE, secretKey);
decryptingCipher = Cipher.getInstance(ALGORITHM);
decryptingCipher.init(Cipher.DECRYPT_MODE, secretKey);
} catch (Exception e) {
throw new RuntimeException("Unable to initialize ciphers.");
}
}
public TEncryptedFramedTransport(TTransport transport, Key secretKey) {
this(transport, secretKey, DEFAULT_MAX_LENGTH);
}
public void open() throws TTransportException {
transport_.open();
}
public boolean isOpen() {
return transport_.isOpen();
}
public void close() {
transport_.close();
}
public int read(byte[] buf, int off, int len) throws TTransportException {
if (readBuffer_ != null) {
int got = readBuffer_.read(buf, off, len);
if (got > 0) {
return got;
}
}
// Read another frame of data
readFrame();
return readBuffer_.read(buf, off, len);
}
@Override
public byte[] getBuffer() {
return readBuffer_.getBuffer();
}
@Override
public int getBufferPosition() {
return readBuffer_.getBufferPosition();
}
@Override
public int getBytesRemainingInBuffer() {
return readBuffer_.getBytesRemainingInBuffer();
}
@Override
public void consumeBuffer(int len) {
readBuffer_.consumeBuffer(len);
}
private final byte[] i32buf = new byte[4];
private void readFrame() throws TTransportException {
transport_.readAll(i32buf, 0, 4);
int size = decodeFrameSize(i32buf);
if (size < 0) {
throw new TTransportException("Read a negative frame size (" + size + ")!");
}
if (size > maxLength_) {
throw new TTransportException("Frame size (" + size + ") larger than max length (" + maxLength_ + ")!");
}
byte[] buff = new byte[size];
transport_.readAll(buff, 0, size);
try {
buff = decryptingCipher.doFinal(buff);
} catch (Exception e) {
throw new TTransportException(0, e);
}
readBuffer_.reset(buff);
}
public void write(byte[] buf, int off, int len) throws TTransportException {
writeBuffer_.write(buf, off, len);
}
@Override
public void flush() throws TTransportException {
byte[] buf = writeBuffer_.get();
int len = writeBuffer_.len();
writeBuffer_.reset();
try {
buf = encryptingCipher.doFinal(buf, 0, len);
} catch (Exception e) {
throw new TTransportException(0, e);
}
encodeFrameSize(buf.length, i32buf);
transport_.write(i32buf, 0, 4);
transport_.write(buf);
transport_.flush();
}
public static void encodeFrameSize(final int frameSize, final byte[] buf) {
buf[0] = (byte) (0xff & (frameSize >> 24));
buf[1] = (byte) (0xff & (frameSize >> 16));
buf[2] = (byte) (0xff & (frameSize >> 8));
buf[3] = (byte) (0xff & (frameSize));
}
public static int decodeFrameSize(final byte[] buf) {
return
((buf[0] & 0xff) << 24) |
((buf[1] & 0xff) << 16) |
((buf[2] & 0xff) << 8) |
((buf[3] & 0xff));
}
}
乘法服务器.java
package tutorial;
import co.runit.prototype.CryptoTool;
import org.apache.thrift.server.TNonblockingServer;
import org.apache.thrift.server.TServer;
import org.apache.thrift.transport.TNonblockingServerSocket;
import org.apache.thrift.transport.TNonblockingServerTransport;
import java.security.Key;
public class MultiplicationServer {
public static MultiplicationHandler handler;
public static MultiplicationService.Processor processor;
public static void main(String[] args) {
try {
handler = new MultiplicationHandler();
processor = new MultiplicationService.Processor(handler);
Runnable simple = () -> startServer(processor);
new Thread(simple).start();
} catch (Exception x) {
x.printStackTrace();
}
}
public static void startServer(MultiplicationService.Processor processor) {
try {
Key key = CryptoTool.decodeKeyBase64("1OUXS3MczVFp3SdfX41U0A==");
TNonblockingServerTransport serverTransport = new TNonblockingServerSocket(9090);
TServer server = new TNonblockingServer(new TNonblockingServer.Args(serverTransport)
.transportFactory(new TEncryptedFramedTransport.Factory(key))
.processor(processor));
System.out.println("Starting the simple server...");
server.serve();
} catch (Exception e) {
e.printStackTrace();
}
}
}
乘法客户端.java
package tutorial;
import co.runit.prototype.CryptoTool;
import org.apache.thrift.TException;
import org.apache.thrift.protocol.TBinaryProtocol;
import org.apache.thrift.protocol.TProtocol;
import org.apache.thrift.transport.TSocket;
import org.apache.thrift.transport.TTransport;
import java.security.Key;
public class MultiplicationClient {
public static void main(String[] args) {
Key key = CryptoTool.decodeKeyBase64("1OUXS3MczVFp3SdfX41U0A==");
try {
TSocket baseTransport = new TSocket("localhost", 9090);
TTransport transport = new TEncryptedFramedTransport(baseTransport, key);
transport.open();
TProtocol protocol = new TBinaryProtocol(transport);
MultiplicationService.Client client = new MultiplicationService.Client(protocol);
perform(client);
transport.close();
} catch (TException x) {
x.printStackTrace();
}
}
private static void perform(MultiplicationService.Client client) throws TException {
int product = client.multiply(3, 5);
System.out.println("3*5=" + product);
}
}
当然，客户端和服务器上的密钥必须相同。生成并存储为 Base64：
public static String generateKey() throws NoSuchAlgorithmException, InvalidAlgorithmParameterException {
KeyGenerator generator = KeyGenerator.getInstance("AES");
generator.init(128);
Key key = generator.generateKey();
return encodeKeyBase64(key);
}
public static String encodeKeyBase64(Key key) {
return Base64.getEncoder().encodeToString(key.getEncoded());
}
public static Key decodeKeyBase64(String encodedKey) {
byte[] keyBytes = Base64.getDecoder().decode(encodedKey);
return new SecretKeySpec(keyBytes, ALGORITHM);
}
UPDATE 2
TFramedTransport 之上的 Python 实现
TEncryptedTransport.py
from cStringIO import StringIO
from struct import pack, unpack
from Crypto.Cipher import AES
from thrift.transport.TTransport import TTransportBase, CReadableTransport
__author__ = 'Marboni'
BLOCK_SIZE = 16
pad = lambda s: s + (BLOCK_SIZE - len(s) % BLOCK_SIZE) * chr(BLOCK_SIZE - len(s) % BLOCK_SIZE)
unpad = lambda s: '' if not s else s[0:-ord(s[-1])]
class TEncryptedFramedTransportFactory:
def __init__(self, key):
self.__key = key
def getTransport(self, trans):
return TEncryptedFramedTransport(trans, self.__key)
class TEncryptedFramedTransport(TTransportBase, CReadableTransport):
def __init__(self, trans, key):
self.__trans = trans
self.__rbuf = StringIO()
self.__wbuf = StringIO()
self.__cipher = AES.new(key)
def isOpen(self):
return self.__trans.isOpen()
def open(self):
return self.__trans.open()
def close(self):
return self.__trans.close()
def read(self, sz):
ret = self.__rbuf.read(sz)
if len(ret) != 0:
return ret
self.readFrame()
return self.__rbuf.read(sz)
def readFrame(self):
buff = self.__trans.readAll(4)
sz, = unpack('!i', buff)
encrypted = StringIO(self.__trans.readAll(sz)).getvalue()
decrypted = unpad(self.__cipher.decrypt(encrypted))
self.__rbuf = StringIO(decrypted)
def write(self, buf):
self.__wbuf.write(buf)
def flush(self):
wout = self.__wbuf.getvalue()
self.__wbuf = StringIO()
encrypted = self.__cipher.encrypt(pad(wout))
encrypted_len = len(encrypted)
buf = pack("!i", encrypted_len) + encrypted
self.__trans.write(buf)
self.__trans.flush()
# Implement the CReadableTransport interface.
@property
def cstringio_buf(self):
return self.__rbuf
def cstringio_refill(self, prefix, reqlen):
while len(prefix) < reqlen:
self.readFrame()
prefix += self.__rbuf.getvalue()
self.__rbuf = StringIO(prefix)
return self.__rbuf
乘法客户端.py
import base64
from thrift import Thrift
from thrift.transport import TSocket
from thrift.protocol import TBinaryProtocol
from tutorial import MultiplicationService, TEncryptedTransport
key = base64.b64decode("1OUXS3MczVFp3SdfX41U0A==")
try:
transport = TSocket.TSocket('localhost', 9090)
transport = TEncryptedTransport.TEncryptedFramedTransport(transport, key)
protocol = TBinaryProtocol.TBinaryProtocol(transport)
client = MultiplicationService.Client(protocol)
transport.open()
product = client.multiply(4, 5, 'Echo!')
print '4*5=%d' % product
transport.close()
except Thrift.TException, tx:
print tx.message
