回调和回包验签支持平台公钥 (#272)

* 回调和回包验签支持使用平台公钥

---------

Co-authored-by: Xiaoyu PENG <peng.xiaoyu@gmail.com>

Author: wujunjiesd

README.md

@@ -233,6 +233,23 @@ Config config =
         .build();
 ```
 
+## 使用本地平台公钥
+
+如果你的商户可使用微信支付的公钥验证应答和回调的签名，可使用微信支付公钥和公钥ID初始化。
+
+```java
+// 可以根据实际情况使用publicKeyFromPath或publicKey加载公钥
+Config config =
+    new RSAPublicKeyConfig.Builder()
+        .merchantId(merchantId)
+        .privateKeyFromPath(privateKeyPath)
+        .publicKeyFromPath(publicKeyPath)
+        .publicKeyId(publicKeyId)
+        .merchantSerialNumber(merchantSerialNumber)
+        .apiV3Key(apiV3Key)
+        .build();
+```
+
 ## 回调通知
 
 首先，你需要在你的服务器上创建一个公开的 HTTP 端点，接受来自微信支付的回调通知。

core/src/main/java/com/wechat/pay/java/core/AbstractRSAConfig.java

@@ -14,11 +14,13 @@
 import com.wechat.pay.java.core.cipher.Signer;
 import com.wechat.pay.java.core.util.PemUtil;
 import java.security.PrivateKey;
+import java.security.PublicKey;
 import java.security.cert.X509Certificate;
 
 /** RSAConfig抽象类 */
 public abstract class AbstractRSAConfig implements Config {
 
+  /** 使用微信支付平台证书验签 */
   protected AbstractRSAConfig(
       String merchantId,
       PrivateKey privateKey,
@@ -28,6 +30,23 @@ protected AbstractRSAConfig(
     this.privateKey = privateKey;
     this.merchantSerialNumber = merchantSerialNumber;
     this.certificateProvider = certificateProvider;
+    this.publicKey = null;
+    this.publicKeyId = null;
+  }
+
+  /** 使用微信支付公钥验签 */
+  protected AbstractRSAConfig(
+      String merchantId,
+      PrivateKey privateKey,
+      String merchantSerialNumber,
+      PublicKey publicKey,
+      String publicKeyId) {
+    this.merchantId = merchantId;
+    this.privateKey = privateKey;
+    this.merchantSerialNumber = merchantSerialNumber;
+    this.certificateProvider = null;
+    this.publicKey = publicKey;
+    this.publicKeyId = publicKeyId;
   }
 
   /** 商户号 */
@@ -42,8 +61,17 @@ protected AbstractRSAConfig(
   /** 微信支付平台证书Provider */
   private final CertificateProvider certificateProvider;
 
+  /** 微信支付平台公钥 */
+  private final PublicKey publicKey;
+
+  /** 微信支付平台公钥Id */
+  private final String publicKeyId;
+
   @Override
   public PrivacyEncryptor createEncryptor() {
+    if (publicKey != null) {
+      return new RSAPrivacyEncryptor(publicKey, publicKeyId);
+    }
     X509Certificate certificate = certificateProvider.getAvailableCertificate();
     return new RSAPrivacyEncryptor(
         certificate.getPublicKey(), PemUtil.getSerialNumber(certificate));
@@ -61,6 +89,9 @@ public Credential createCredential() {
 
   @Override
   public Validator createValidator() {
+    if (publicKey != null) {
+      return new WechatPay2Validator(new RSAVerifier(publicKey, publicKeyId));
+    }
     return new WechatPay2Validator(new RSAVerifier(certificateProvider));
   }
 

core/src/main/java/com/wechat/pay/java/core/RSAPublicKeyConfig.java

@@ -0,0 +1,120 @@
+package com.wechat.pay.java.core;
+
+import static com.wechat.pay.java.core.notification.Constant.AES_CIPHER_ALGORITHM;
+import static com.wechat.pay.java.core.notification.Constant.RSA_SIGN_TYPE;
+import static java.util.Objects.requireNonNull;
+
+import com.wechat.pay.java.core.cipher.AeadAesCipher;
+import com.wechat.pay.java.core.cipher.AeadCipher;
+import com.wechat.pay.java.core.cipher.RSAVerifier;
+import com.wechat.pay.java.core.cipher.Verifier;
+import com.wechat.pay.java.core.notification.NotificationConfig;
+import com.wechat.pay.java.core.util.PemUtil;
+import java.nio.charset.StandardCharsets;
+import java.security.PublicKey;
+
+/** 使用微信支付平台公钥的RSA配置类。 每次构造都要求传入平台公钥以及平台公钥id，如果使用平台证书建议用RSAAutoCertificateConfig类 */
+public final class RSAPublicKeyConfig extends AbstractRSAConfig implements NotificationConfig {
+
+  private final PublicKey publicKey;
+  private final AeadCipher aeadCipher;
+  private final String publicKeyId;
+
+  private RSAPublicKeyConfig(Builder builder) {
+    super(
+        builder.merchantId,
+        builder.privateKey,
+        builder.merchantSerialNumber,
+        builder.publicKey,
+        builder.publicKeyId);
+    this.publicKey = builder.publicKey;
+    this.publicKeyId = builder.publicKeyId;
+    this.aeadCipher = new AeadAesCipher(builder.apiV3Key);
+  }
+
+  /**
+   * 获取签名类型
+   *
+   * @return 签名类型
+   */
+  @Override
+  public String getSignType() {
+    return RSA_SIGN_TYPE;
+  }
+
+  /**
+   * 获取认证加解密器类型
+   *
+   * @return 认证加解密器类型
+   */
+  @Override
+  public String getCipherType() {
+    return AES_CIPHER_ALGORITHM;
+  }
+
+  /**
+   * 创建验签器
+   *
+   * @return 验签器
+   */
+  @Override
+  public Verifier createVerifier() {
+    return new RSAVerifier(publicKey, publicKeyId);
+  }
+
+  /**
+   * 创建认证加解密器
+   *
+   * @return 认证加解密器
+   */
+  @Override
+  public AeadCipher createAeadCipher() {
+    return aeadCipher;
+  }
+
+  public static class Builder extends AbstractRSAConfigBuilder<Builder> {
+    protected byte[] apiV3Key;
+    protected PublicKey publicKey;
+    protected String publicKeyId;
+
+    public Builder apiV3Key(String apiV3Key) {
+      this.apiV3Key = apiV3Key.getBytes(StandardCharsets.UTF_8);
+      return self();
+    }
+
+    public Builder publicKey(String publicKey) {
+      this.publicKey = PemUtil.loadPublicKeyFromString(publicKey);
+      return self();
+    }
+
+    public Builder publicKey(PublicKey publicKey) {
+      this.publicKey = publicKey;
+      return self();
+    }
+
+    public Builder publicKeyFromPath(String publicKeyPath) {
+      this.publicKey = PemUtil.loadPublicKeyFromPath(publicKeyPath);
+      return self();
+    }
+
+    public Builder publicKeyId(String publicKeyId) {
+      this.publicKeyId = publicKeyId;
+      return self();
+    }
+
+    @Override
+    protected Builder self() {
+      return this;
+    }
+
+    public RSAPublicKeyConfig build() {
+      requireNonNull(merchantId);
+      requireNonNull(publicKey);
+      requireNonNull(publicKeyId);
+      requireNonNull(privateKey);
+      requireNonNull(merchantSerialNumber);
+
+      return new RSAPublicKeyConfig(this);
+    }
+  }
+}

core/src/main/java/com/wechat/pay/java/core/certificate/CertificateDownloader.java

@@ -6,13 +6,13 @@
 import com.wechat.pay.java.core.certificate.model.DownloadCertificateResponse;
 import com.wechat.pay.java.core.certificate.model.EncryptCertificate;
 import com.wechat.pay.java.core.cipher.AeadCipher;
+import com.wechat.pay.java.core.exception.ServiceException;
 import com.wechat.pay.java.core.http.Constant;
 import com.wechat.pay.java.core.http.HttpClient;
 import com.wechat.pay.java.core.http.HttpMethod;
 import com.wechat.pay.java.core.http.HttpRequest;
 import com.wechat.pay.java.core.http.HttpResponse;
 import com.wechat.pay.java.core.http.MediaType;
-import com.wechat.pay.java.core.util.PemUtil;
 import java.nio.charset.StandardCharsets;
 import java.security.cert.X509Certificate;
 import java.util.Base64;
@@ -77,16 +77,17 @@ public Map<String, X509Certificate> download() {
             .addHeader(Constant.ACCEPT, " */*")
             .addHeader(Constant.CONTENT_TYPE, MediaType.APPLICATION_JSON.getValue())
             .build();
-    HttpResponse<DownloadCertificateResponse> httpResponse =
-        httpClient.execute(httpRequest, DownloadCertificateResponse.class);
-
-    Map<String, X509Certificate> downloaded = decryptCertificate(httpResponse);
-    validateCertificate(downloaded);
-    return downloaded;
-  }
-
-  private void validateCertificate(Map<String, X509Certificate> certificates) {
-    certificates.forEach((serialNo, cert) -> certificateHandler.validateCertPath(cert));
+    try {
+      HttpResponse<DownloadCertificateResponse> httpResponse =
+          httpClient.execute(httpRequest, DownloadCertificateResponse.class);
+      return decryptCertificate(httpResponse);
+    } catch (ServiceException e) {
+      // 如果证书不存在，可能是切换为平台公钥，该处不报错
+      if (e.getErrorCode().equals("NOT_FOUND")) {
+        return new HashMap<>();
+      }
+      throw e;
+    }
   }
 
   /**
@@ -109,7 +110,7 @@ private Map<String, X509Certificate> decryptCertificate(
               Base64.getDecoder().decode(encryptCertificate.getCiphertext()));
 
       certificate = certificateHandler.generateCertificate(decryptCertificate);
-      downloadCertMap.put(PemUtil.getSerialNumber(certificate), certificate);
+      downloadCertMap.put(data.getSerialNo(), certificate);
     }
     return downloadCertMap;
   }

core/src/main/java/com/wechat/pay/java/core/certificate/CertificateHandler.java

@@ -14,7 +14,7 @@ public interface CertificateHandler {
   X509Certificate generateCertificate(String certificate);
 
   /**
-   * * 验证证书链
+   * * 验证证书链（不推荐验证，如果证书过期不及时更换会导致验证失败，从而影响业务）
    *
    * @param certificate 微信支付平台证书
    * @throws com.wechat.pay.java.core.exception.ValidationException 证书验证失败

core/src/main/java/com/wechat/pay/java/core/certificate/RSACertificateHandler.java

@@ -1,69 +1,17 @@
 package com.wechat.pay.java.core.certificate;
 
-import com.wechat.pay.java.core.exception.ValidationException;
 import com.wechat.pay.java.core.util.PemUtil;
 import java.security.cert.*;
-import java.util.*;
 
 final class RSACertificateHandler implements CertificateHandler {
 
-  private static final X509Certificate tenpayCACert =
-      PemUtil.loadX509FromString(
-          "-----BEGIN CERTIFICATE-----\n"
-              + "MIIEcDCCA1igAwIBAgIUG9QiDlDbwEsGrTl1SYRsAcPo69IwDQYJKoZIhvcNAQEL\n"
-              + "BQAwcDELMAkGA1UEBhMCQ04xEzARBgNVBAoMCmlUcnVzQ2hpbmExHDAaBgNVBAsM\n"
-              + "E0NoaW5hIFRydXN0IE5ldHdvcmsxLjAsBgNVBAMMJWlUcnVzQ2hpbmEgQ2xhc3Mg\n"
-              + "MiBFbnRlcnByaXNlIENBIC0gRzMwHhcNMTcwODA5MDkxNTU1WhcNMzIwODA5MDkx\n"
-              + "NTU1WjBeMQswCQYDVQQGEwJDTjETMBEGA1UEChMKVGVucGF5LmNvbTEdMBsGA1UE\n"
-              + "CxMUVGVucGF5LmNvbSBDQSBDZW50ZXIxGzAZBgNVBAMTElRlbnBheS5jb20gUm9v\n"
-              + "dCBDQTCCASIwDQYJKoZIhvcNAQEBBQADggEPADCCAQoCggEBALvnPD6k39BdPYAH\n"
-              + "+6lnWPjuHH+2pcmZUf2E8cNFQFNr+ECRZylYV2iKyItCQt3I2/7VIDZl6aR9TE7n\n"
-              + "sZrtSmOXCw635QOrq2yF9LTSDotAhf3ER0+216w3age/VzGcNVQpTf6gRCHCuQIk\n"
-              + "8pe/oh06JagGvX0wERa+I6NfuG58ZHQY9d6RqLXKQl0Up95v73HDsG487z8k6jcn\n"
-              + "qpGngmHQxdWiWRJugqxNRUD+awv2/DUsqGOffPX4jzJ6rLSJSlQXvuniDYxmaiaD\n"
-              + "cK0bUbB5aM+1zMwogoHSYxWj/6B+vgcnHQCUrwGdiQR5+F+yRWzy5bO09IzaFgeO\n"
-              + "PNPLPOsCAwEAAaOCARIwggEOMBIGA1UdEwEB/wQIMAYBAf8CAQAwDgYDVR0PAQH/\n"
-              + "BAQDAgEGMCAGA1UdEQQZMBekFTATMREwDwYDVQQDDAhzd2JlLTI2NjAdBgNVHQ4E\n"
-              + "FgQUTFo4GLdm9oHX52HcWnzuL4tui2gwHwYDVR0jBBgwFoAUK1vVxWgI69vN5LA5\n"
-              + "MqJf/8dPmEUwRgYDVR0gBD8wPTA7BgoqgRyG7xcBAQECMC0wKwYIKwYBBQUHAgEW\n"
-              + "H2h0dHBzOi8vd3d3Lml0cnVzLmNvbS5jbi9jdG5jcHMwPgYDVR0fBDcwNTAzoDGg\n"
-              + "L4YtaHR0cDovL3RvcGNhLml0cnVzLmNvbS5jbi9jcmwvaXRydXNjMmNhZzMuY3Js\n"
-              + "MA0GCSqGSIb3DQEBCwUAA4IBAQBwZhL/eiOQmMyo1D0IR9mu1DPWl5J3XXhjc4R6\n"
-              + "mFgsN/FCeVP9M4U9y2FJH6i5Ha5YCecKGw5pwhA0rjZr/6okWwo22GF+nzI/gQiz\n"
-              + "6ugAKs5VjFbeiEb04Ncz4HT8FP1idK3tyCjqCUTkLNt0U3tR7wy26hgOqlT2wCZ9\n"
-              + "X4MfT8dUMdt9nCZx4ujN5yZOzaLOCHmzoGDGxgKg91bbu0TG2Yzd2ylhrxxRtFH9\n"
-              + "aZ/J1x5UoF7uwhTM8P92DuAldWC1/bX1kciOtQvQEZeAy+9y/1BtFxoBnmDxnqkX\n"
-              + "+lirIUYTLDaL7HaLrOLECUlaxZCU/Nkwm3tmqQxtCh+XQBdd\n"
-              + "-----END CERTIFICATE-----");
-
-  private static final Set<TrustAnchor> trustAnchor =
-      new LinkedHashSet<>(Collections.singletonList(new TrustAnchor(tenpayCACert, null)));
-
   @Override
   public X509Certificate generateCertificate(String certificate) {
     return PemUtil.loadX509FromString(certificate);
   }
 
   @Override
   public void validateCertPath(X509Certificate certificate) {
-    try {
-      PKIXParameters params = new PKIXParameters(trustAnchor);
-      params.setRevocationEnabled(false);
-
-      List<X509Certificate> certs = new ArrayList<>();
-      certs.add(certificate);
-
-      CertificateFactory cf = CertificateFactory.getInstance("X.509");
-      CertPath certPath = cf.generateCertPath(certs);
-
-      CertPathValidator validator = CertPathValidator.getInstance("PKIX");
-      validator.validate(certPath, params);
-    } catch (Exception e) {
-      throw new ValidationException(
-          String.format(
-              "certificate[%s] validation failed: %s",
-              PemUtil.getSerialNumber(certificate), e.getMessage()),
-          e);
-    }
+    // 为防止证书过期导致验签失败，从而影响业务，后续不再验证证书信任链
   }
 }