Python与Java程序RSA,AES加密相互通信

python版本3.6, 在windows以及linux上都进行过测试

由于python中rsa加密存在长度限制, 虽然可以通过分片加密来解决,
但是更好的做法是通过rsa加密传输aes密钥给服务器, 携带的信息通过该密钥进行aes加密,
服务器通过rsa私钥得到aes密钥后解析信息, 并继续使用密钥进行双向通信

python中加密使用pycryptodome模块

pip install pycryptodome

Python

其中接受的参数text,key均为字符串

from Crypto.PublicKey import RSA
from Crypto.Cipher import PKCS1_v1_5
from Crypto.Cipher import AES
from base64 import b64decode
from base64 import b64encode
import re


def rsa_encode(text, public_key):
    key = RSA.importKey(b64decode(public_key))
    cipher = PKCS1_v1_5.new(key)
    return b64encode(cipher.encrypt(text.encode(encoding='utf-8'))).decode('utf-8')


def aes_encode(text, key):
    key = key.encode('utf-8')
    cipher = AES.new(key, AES.MODE_CBC, key)
    text = text + (16 - len(text) % 16) * chr(16 - len(text) % 16)
    return b64encode(cipher.encrypt(text.encode(encoding='utf-8'))).decode('utf-8')


def aes_decode(cipher_text, key):
    key = key.encode('utf-8')
    cipher = AES.new(key, AES.MODE_CBC, key)
    text = cipher.decrypt(b64decode(cipher_text)).decode('utf-8')
    return re.compile('[\\x00-\\x08\\x0b-\\x0c\\x0e-\\x1f\n\r\t]').sub('', text)

Java

java的加密代码不依赖其他包

AesUtils

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.util.Base64;
import java.util.UUID;

public class AesUtils {

    private static final String TYPE = "AES";
    private static final String ALGORITHM = "AES/CBC/PKCS5Padding";
    private static final String CHARSET = "UTF-8";

    public static String createKey(){
        return UUID.randomUUID().toString().replace("-","").substring(16);
    }

    public static String encrypt(String data, String key) throws Exception {
        IvParameterSpec ivParameterSpec = new IvParameterSpec(key.getBytes());
        SecretKeySpec keySpec = new SecretKeySpec(key.getBytes(), TYPE);
        Cipher cipher = Cipher.getInstance(ALGORITHM);
        cipher.init(Cipher.ENCRYPT_MODE, keySpec, ivParameterSpec);
        return Base64.getEncoder().encodeToString(cipher.doFinal(data.getBytes(CHARSET)));
    }

    public static String decrypt(String data, String key) throws Exception {
        IvParameterSpec ivParameterSpec = new IvParameterSpec(key.getBytes());
        SecretKeySpec keySpec = new SecretKeySpec(key.getBytes(), TYPE);
        Cipher cipher = Cipher.getInstance(ALGORITHM);
        cipher.init(Cipher.DECRYPT_MODE, keySpec, ivParameterSpec);
        return new String(cipher.doFinal(Base64.getDecoder().decode(data.getBytes())), CHARSET);
    }
}

RsaUtils

import javax.crypto.Cipher;
import java.io.ByteArrayOutputStream;
import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import java.util.Base64;

public class RsaUtils {

    private static final String TYPE = "RSA";
    private static final String ALGORITHM = "RSA/ECB/PKCS1PADDING";
    private static final String CHARSET = "UTF-8";
    private static final int KEY_SIZE = 1024;

    public static KeyPair createKeyPair() {
        try {
            KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance(TYPE);
            keyPairGenerator.initialize(KEY_SIZE);
            return keyPairGenerator.generateKeyPair();
        } catch (Exception e) {
            return null;
        }
    }

    public static String getPublicKey(KeyPair keyPair) {
        return Base64.getEncoder().encodeToString(keyPair.getPublic().getEncoded());
    }

    public static String getPrivateKey(KeyPair keyPair) {
        return Base64.getEncoder().encodeToString(keyPair.getPrivate().getEncoded());
    }

    public static String encrypt(String data, String publicKeyString) throws Exception {
        Cipher cipher = Cipher.getInstance(ALGORITHM);
        KeyFactory keyFactory = KeyFactory.getInstance(TYPE);
        X509EncodedKeySpec keySpec = new X509EncodedKeySpec(Base64.getDecoder().decode(publicKeyString));
        RSAPublicKey publicKey = (RSAPublicKey) keyFactory.generatePublic(keySpec);
        cipher.init(Cipher.ENCRYPT_MODE, publicKey);
        return Base64.getEncoder().encodeToString(splitCodec(cipher, Cipher.ENCRYPT_MODE, data.getBytes(CHARSET)));
    }

    public static String decrypt(String data, String privateKeyString) throws Exception {
        Cipher cipher = Cipher.getInstance(ALGORITHM);
        KeyFactory keyFactory = KeyFactory.getInstance(TYPE);
        PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(Base64.getDecoder().decode(privateKeyString));
        RSAPrivateKey privateKey = (RSAPrivateKey) keyFactory.generatePrivate(keySpec);
        cipher.init(Cipher.DECRYPT_MODE, privateKey);
        return new String(splitCodec(cipher, Cipher.DECRYPT_MODE, Base64.getDecoder().decode(data)), CHARSET);
    }

    private static byte[] splitCodec(Cipher cipher, int mode, byte[] data) throws Exception {
        int maxBlock = KEY_SIZE / 8 - (mode == Cipher.DECRYPT_MODE ? 0 : 11);
        try (ByteArrayOutputStream out = new ByteArrayOutputStream()) {
            byte[] buffer;
            for (int offset = 0; offset < data.length; offset += maxBlock) {
                buffer = cipher.doFinal(data, offset, Math.min(maxBlock, data.length - offset));
                out.write(buffer, 0, buffer.length);
            }
            return out.toByteArray();
        }
    }
}