基於MD5+RSA算法實現接口調用防扯皮級鑒權

概述

最近項目中需要對第三方開發接口調用，考慮了一下，准備采用MD5+RSA算對請求數據進行簽名，來達到請求鑒權，過濾非法請求的目標。
數字簽名采用MD5+RSA算法實現。RSA私鑰要嚴格保密並提供安全存儲介質，數字簽名使用java.security.Signature 包中規定的“MD5withRSA”算法實現。私鑰簽名，公鑰驗簽即接口調用方存儲私鑰並用私鑰對請求數據進行簽名，平台方存儲調用方提供的公鑰，對於調用方的簽名進行驗簽，驗簽通過才會接收調用方請求的數據。

簡易流程

1、從平台獲取32位businessId,備用
2、本地生成keyPair，其中privateKey自行保存，需要將publicKey提供給平台
3、signature字段為businessId + signature結果
4、簽名數據根據以接口限定為准

KeyPair生成、簽名及驗簽

keyPair生成

private static final String KEY_ALGORITHM = "RSA";
private static final String SIGNATURE_ALGORITHM = "MD5withRSA";
private static final String CHARSET = "UTF-8";
private ThreadLocal<String> publicKey = new ThreadLocal<>();
private ThreadLocal<String> privateKey = new ThreadLocal<>();

public CustomKeyPair generateKeyPair() throws NoSuchAlgorithmException {
    KeyPairGenerator keygen = java.security.KeyPairGenerator
            .getInstance(KEY_ALGORITHM);
    SecureRandom secureRandom = new SecureRandom();
    secureRandom.setSeed("remote".getBytes()); // 初始化隨機產生器
    keygen.initialize(1024);
    KeyPair keys = keygen.genKeyPair();
    RSAPublicKey publicKey = (RSAPublicKey) keys.getPublic();
    RSAPrivateKey privateKey = (RSAPrivateKey) keys.getPrivate();
    CustomKeyPair customKeyPair = CustomKeyPair.builder()
            .privateKey(Base64Utils.encodeToString(privateKey.getEncoded()))
            .publicKey(Base64Utils.encodeToString(publicKey.getEncoded()))
            .build();
    log.info("privateKey:{}", customKeyPair.getPrivateKey());
    log.info("publicKey:{}", customKeyPair.getPublicKey());
    return customKeyPair;
}

@Data
@Builder
private static class CustomKeyPair {
    private String privateKey;
    private String publicKey;
}

簽名調用示例

SignatureTool.I.putPrivateKey(customKeyPair.privateKey).signature("測試簽名數據")

簽名代碼實現：

public String signature(String data) {
    try {
        return signature(data.getBytes(CHARSET));
    } catch (NoSuchAlgorithmException e) {
        e.printStackTrace();
        throw new RuntimeException("加密算法不存在");
    } catch (SignatureException e) {
        e.printStackTrace();
        throw new RuntimeException("數據簽名不存在");
    } catch (InvalidKeyException | InvalidKeySpecException e) {
        e.printStackTrace();
        throw new RuntimeException("數字簽名key異常");
    } catch (UnsupportedEncodingException e) {
        e.printStackTrace();
        throw new RuntimeException("不支持的字符編碼");
    }
}

  /**
    * 數字簽名算法
    *
    * @param data 簽名數據
    * @return 簽名結果
    * @throws NoSuchAlgorithmException 沒有此種加密算法異常
    * @throws SignatureException       簽名異常
    * @throws InvalidKeyException      不可用的私鑰
    */
private String signature(byte[] data) throws NoSuchAlgorithmException, SignatureException, InvalidKeyException, InvalidKeySpecException {
    byte[] keyBytes = Base64Utils.decodeFromString(this.privateKey.get());
    PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(keyBytes);
    KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
    PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec);
    Signature signature = Signature.getInstance(SIGNATURE_ALGORITHM);
    signature.initSign(privateKey);
    signature.update(data);
    return Base64Utils.encodeToString(Base64Utils.encodeToString(signature.sign()).getBytes());
}

驗簽調用示例

SignatureTool.I.putPublicKey(customKeyPair.publicKey).verifySignature("測試簽名數據", signature);

驗簽代碼實現：

public boolean verifySignature(String data, String signature) {
    try {
        return verifySignature(data.getBytes(CHARSET), signature);
    } catch (NoSuchAlgorithmException e) {
        log.warn("加密算法不存在");
    } catch (SignatureException e) {
        log.warn("數據簽名不存在");
    } catch (InvalidKeyException | InvalidKeySpecException e) {
        log.warn("數字簽名key異常");
    } catch (UnsupportedEncodingException e) {
        log.warn("不支持的字符編碼");
    }
    return false;
}

  /**
    * 數字簽名驗證
    *
    * @param data 驗簽數據
    * @param sign 簽名
    * @return 驗簽結果
    * @throws NoSuchAlgorithmException 沒有此種加密算法異常
    * @throws SignatureException       簽名異常
    * @throws InvalidKeyException      不可用的私鑰
    */
private boolean verifySignature(byte[] data, String sign) throws NoSuchAlgorithmException, InvalidKeyException, SignatureException, InvalidKeySpecException {
    byte[] signs = Base64Utils.decode(Base64Utils.decodeFromString(sign));
    byte[] publicKey = Base64Utils.decodeFromString(this.publicKey.get());
    X509EncodedKeySpec keySpec = new X509EncodedKeySpec(publicKey);
    KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
    PublicKey pubKey = keyFactory.generatePublic(keySpec);
    Signature signature = Signature.getInstance(SIGNATURE_ALGORITHM);
    signature.initVerify(pubKey);
    signature.update(data);
    return signature.verify(signs);
}

調用示例

簽名的數據可以根據實際的業務接口不同，單獨設置，雙方統一標准

public static void main(String[] args) throws NoSuchAlgorithmException {
    //生成秘鑰對
    CustomKeyPair customKeyPair = SignatureTool.I.generateKeyPair();
    //私鑰簽名
    String signature = SignatureTool.I.putPrivateKey(customKeyPair.privateKey).signature("測試簽名數據");
    //公鑰驗簽
    SignatureTool.I.putPublicKey(customKeyPair.publicKey).verifySignature("測試簽名數據", signature);
}

這樣，我們只要給每個調用方分配一個businessId，由調用提供公鑰並與映射到businessId，私鑰自始至終一直由調用方存儲，我們可以直接判定數據的提交來自哪個業務方，接口調用的安全性可以得到有效的保證，后續可以通過增加諸如ip白名單之類的限制，進一步加強接口的安全性，尤其在多方調用的場景下，防扯皮效果顯著，另外被調用方也可以為業務方生成單獨的keypair，實現雙向驗簽的雙保險機制。

SignatureTool 完整代碼如下：

import lombok.Builder;
import lombok.Data;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.Base64Utils;

import java.io.UnsupportedEncodingException;
import java.security.*;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.InvalidKeySpecException;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import java.util.Locale;

@Slf4j
public enum SignatureTool {
    I;

    private static final String KEY_ALGORITHM = "RSA";
    private static final String SIGNATURE_ALGORITHM = "MD5withRSA";
    private static final String CHARSET = "UTF-8";
    private ThreadLocal<String> publicKey = new ThreadLocal<>();
    private ThreadLocal<String> privateKey = new ThreadLocal<>();

    /**
     * 數字簽名
     *
     * @param data 簽名內容
     * @return 簽名
     */
    public String signature(String data) {
        try {
            return signature(data.getBytes(CHARSET));
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
            throw new RuntimeException("加密算法不存在");
        } catch (SignatureException e) {
            e.printStackTrace();
            throw new RuntimeException("數據簽名不存在");
        } catch (InvalidKeyException | InvalidKeySpecException e) {
            e.printStackTrace();
            throw new RuntimeException("數字簽名key異常");
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
            throw new RuntimeException("不支持的字符編碼");
        }
    }

    public boolean verifySignature(String data, String signature) {
        try {
            return verifySignature(data.getBytes(CHARSET), signature);
        } catch (NoSuchAlgorithmException e) {
            log.warn("加密算法不存在");
        } catch (SignatureException e) {
            log.warn("數據簽名不存在");
        } catch (InvalidKeyException | InvalidKeySpecException e) {
            log.warn("數字簽名key異常");
        } catch (UnsupportedEncodingException e) {
            log.warn("不支持的字符編碼");
        }
        return false;
    }

    /**
     * 初始化公鑰、私鑰
     */
    public SignatureTool initKeys(String privateKey, String publicKey) {
        this.publicKey.set(publicKey);
        this.privateKey.set(privateKey);
        return this;
    }

    public SignatureTool putPublicKey(String publicKey) {
        this.publicKey.set(publicKey);
        return this;
    }

    public SignatureTool putPrivateKey(String privateKey) {
        this.privateKey.set(privateKey);
        return this;
    }

    public CustomKeyPair generateKeyPair() throws NoSuchAlgorithmException {
        KeyPairGenerator keygen = KeyPairGenerator
                .getInstance(KEY_ALGORITHM);
        SecureRandom secureRandom = new SecureRandom();
        secureRandom.setSeed("ainoteRemote".getBytes()); // 初始化隨機產生器
        keygen.initialize(1024);
        KeyPair keys = keygen.genKeyPair();
        RSAPublicKey publicKey = (RSAPublicKey) keys.getPublic();
        RSAPrivateKey privateKey = (RSAPrivateKey) keys.getPrivate();
        CustomKeyPair customKeyPair = CustomKeyPair.builder()
                .privateKey(Base64Utils.encodeToString(privateKey.getEncoded()))
                .publicKey(Base64Utils.encodeToString(publicKey.getEncoded()))
                .build();
        log.info("privateKey:{}", customKeyPair.getPrivateKey());
        log.info("publicKey:{}", customKeyPair.getPublicKey());
        return customKeyPair;
    }

    /**
     * 數字簽名算法
     *
     * @param data 簽名數據
     * @return 簽名結果
     * @throws NoSuchAlgorithmException 沒有此種加密算法異常
     * @throws SignatureException       簽名異常
     * @throws InvalidKeyException      不可用的私鑰
     */
    private String signature(byte[] data) throws NoSuchAlgorithmException, SignatureException, InvalidKeyException, InvalidKeySpecException {
        byte[] keyBytes = Base64Utils.decodeFromString(this.privateKey.get());
        PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(keyBytes);
        KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
        PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec);
        Signature signature = Signature.getInstance(SIGNATURE_ALGORITHM);
        signature.initSign(privateKey);
        signature.update(data);
        return Base64Utils.encodeToString(Base64Utils.encodeToString(signature.sign()).getBytes());
    }

    /**
     * 數字簽名驗證
     *
     * @param data 驗簽數據
     * @param sign 簽名
     * @return 驗簽結果
     * @throws NoSuchAlgorithmException 沒有此種加密算法異常
     * @throws SignatureException       簽名異常
     * @throws InvalidKeyException      不可用的私鑰
     */
    private boolean verifySignature(byte[] data, String sign) throws NoSuchAlgorithmException, InvalidKeyException, SignatureException, InvalidKeySpecException {
        byte[] signs = Base64Utils.decode(Base64Utils.decodeFromString(sign));
        byte[] publicKey = Base64Utils.decodeFromString(this.publicKey.get());
        X509EncodedKeySpec keySpec = new X509EncodedKeySpec(publicKey);
        KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
        PublicKey pubKey = keyFactory.generatePublic(keySpec);
        Signature signature = Signature.getInstance(SIGNATURE_ALGORITHM);
        signature.initVerify(pubKey);
        signature.update(data);
        return signature.verify(signs);
    }

    @Data
    @Builder
    private static class CustomKeyPair {
        private String privateKey;
        private String publicKey;
    }

    public static void main(String[] args) throws NoSuchAlgorithmException {
        System.out.println(CommonUtil.newUUID().toUpperCase(Locale.ROOT));
        CustomKeyPair customKeyPair = SignatureTool.I.generateKeyPair();
        Long timeStamp = System.currentTimeMillis();
        String signature = SignatureTool.I.putPrivateKey(customKeyPair.privateKey).signature(timeStamp+"");
        System.out.println(timeStamp);
        log.debug(signature);
        SignatureTool.I.putPublicKey(customKeyPair.publicKey).verifySignature(timeStamp+"", signature);
    }
}