无法从 Golang 中的 iOS 解析 base64 DER 编码的 ASN.1 public 密钥

Question

我在 Golang 中有一个带有 RSA 加密的项目，所以现在，我有一个用于加密消息的 Base64 public 密钥格式，

我使用了这个代码：

publicKeyBase64 = "MIGJAoGBAJJYXgBem1scLKPEjwKrW8+ci3B/YNN3aY2DJ3lc5e2wNc0SmFikDpow1TdYcKl2wdrXX7sMRsyjTk15IECMezyHzaJGQ9TinnkQixJ+YnlNdLC04TNWOg13plyahIXBforYAjYl2wVIA8Yma2bEQFhmAFkEX1A/Q1dIKy6EfQ+xAgMBAAE="
publicKeyBinary, err := base64.StdEncoding.DecodeString(publicKeyBase64)

publicKeyInterface, err := x509.ParsePKIXPublicKey(publicKeyBinary)
    if err != nil {
    fmt.Println("Could not parse DER encoded public key (encryption key)")
    return "","",err
}

publicKey, isRSAPublicKey := publicKeyInterface.(*rsa.PublicKey)
if !isRSAPublicKey {
    fmt.Println("Public key parsed is not an RSA public key")
    return "","",err
}

encryptedMessage, err := rsa.EncryptPKCS1v15(rand.Reader, publicKey, "message")

当我运行这段代码时，我得到了这个错误：

Could not parse DER encoded public key (encryption key)

asn1: structure error: tags don't match (16 vs {class:0 tag:2 length:129 isCompound:false}) {optional:false explicit:false application:false defaultValue:<nil> tag:<nil> stringType:0 timeType:0 set:false omitEmpty:false} AlgorithmIdentifier @3

错误指向publicKeyInterface，无法从Base64解码格式解析为public密钥，我的代码有什么问题？

=======已更新=====

我的 publicKeyBase64 是从我的二进制数据类型的模型中检索到的

当我将它从我的 Rails API 存储在我的 mongoDB 中时，我收到 public_key 参数作为 Base64 格式，但我将其解码为二进制，然后我用此代码存储它

def create
  params = device_params      
  public_key = Base64.decode64 device_params[:public_key]
  #device_params[:public_key] value is "MIGJAoGBAJJYXgBem1scLKPEjwKrW8+ci3B/YNN3aY2DJ3lc5e2wNc0SmFikDpow1TdYcKl2wdrXX7sMRsyjTk15IECMezyHzaJGQ9TinnkQixJ+YnlNdLC04TNWOg13plyahIXBforYAjYl2wVIA8Yma2bEQFhmAFkEX1A/Q1dIKy6EfQ+xAgMBAAE="
  params[:public_key] = BSON::Binary.new(public_key, :generic)
  device = Device.find_or_create_by(id: device_params[:id])

  render_success device.update_attributes(params), device
end

当我使用 rails 代码使用此代码转换我的 Base64 public 密钥字符串时，它成功了：

rsa_public_key = OpenSSL::PKey::RSA.new(Base64.decode64(public_key))

在我的 iOS 应用程序中，我使用 https://github.com/DigitalLeaves/AsymmetricCrypto 使用此代码生成 public 密钥：

AsymmetricCryptoManager.sharedInstance.createSecureKeyPair({ (success, error) -> Void in
   if success {
    print("RSA-1024 keypair successfully generated.")
    let publicKey = AsymmetricCryptoManager.sharedInstance.getPublicKeyData()?.base64EncodedString()

    let url = ENV.BASE_URL + "devices"
    let headers = ["Authentication-Token": CurrentUser.getCurrentUser().token] as! HTTPHeaders
    let params = ["device[user_id]": CurrentUser.getCurrentUser().id!, "device[id]": instanceID,"device[token]": fcmToken, "device[os]": "ios", "device[public_key]": publicKey!]

    Alamofire.request(url, method: .post, parameters: params, encoding: URLEncoding.default, headers: headers)
} else { print("An error happened while generating a keypair: \(error)") }
})

Answer 1

我们可以转储 ASN.1 内容以查看它们的外观：

$ echo "MIGJAoGBAJJYXgBem1scLKPEjwKrW8+ci3B/YNN3aY2DJ3lc5e2wNc0SmFikDpow1TdYcKl2wdrXX7sMRsyjTk15IECMezyHzaJGQ9TinnkQixJ+YnlNdLC04TNWOg13plyahIXBforYAjYl2wVIA8Yma2bEQFhmAFkEX1A/Q1dIKy6EfQ+xAgMBAAE=" | \
    base64 -d | \
    dumpasn1 -
  0 137: SEQUENCE {
  3 129:   INTEGER
       :     00 92 58 5E 00 5E 9B 5B 1C 2C A3 C4 8F 02 AB 5B
       :     CF 9C 8B 70 7F 60 D3 77 69 8D 83 27 79 5C E5 ED
       :     B0 35 CD 12 98 58 A4 0E 9A 30 D5 37 58 70 A9 76
       :     C1 DA D7 5F BB 0C 46 CC A3 4E 4D 79 20 40 8C 7B
       :     3C 87 CD A2 46 43 D4 E2 9E 79 10 8B 12 7E 62 79
       :     4D 74 B0 B4 E1 33 56 3A 0D 77 A6 5C 9A 84 85 C1
       :     7E 8A D8 02 36 25 DB 05 48 03 C6 26 6B 66 C4 40
       :     58 66 00 59 04 5F 50 3F 43 57 48 2B 2E 84 7D 0F
       :     B1
135   3:   INTEGER 65537
       :   }

0 warnings, 0 errors.

格式正确的 ASN.1 public 密钥也应包括算法。我们应该有一行类似于：

  5   9:     OBJECT IDENTIFIER rsaEncryption (1 2 840 113549 1 1 1)

AsymmetricCryptoManager.getPublicKeyData() returns 非常准系统的 ASN.1 密钥，没有任何算法信息。这让 Go 非常不高兴，因为它无法知道它是什么类型的密钥。参见 more about correctly exporting the key here。

如果可以更改 iOS 代码，则应改用 CryptoExportImportManager and use one of exportPublicKeyToPEM or exportPublicKeyToDER. These take the output of getPublicKeyData and generate output usable by other tools. You can find an example of how to use them in the CryptoExportImportManager example.

如果无法更改密钥导出代码，则可以直接在 Go 中解析它。这假设您确定它是一个 RSA public 密钥：

func main() {
    publicKeyBase64 := "MIGJAoGBAJJYXgBem1scLKPEjwKrW8+ci3B/YNN3aY2DJ3lc5e2wNc0SmFikDpow1TdYcKl2wdrXX7sMRsyjTk15IECMezyHzaJGQ9TinnkQixJ+YnlNdLC04TNWOg13plyahIXBforYAjYl2wVIA8Yma2bEQFhmAFkEX1A/Q1dIKy6EfQ+xAgMBAAE="

    // Base64 decode.
    publicKeyBinary, err := base64.StdEncoding.DecodeString(publicKeyBase64)
    if err != nil {
        panic(err)
    }

    // rsa.PublicKey is a big.Int (N: modulus) and an integer (E: exponent).
    var pubKey rsa.PublicKey
    if rest, err := asn1.Unmarshal(publicKeyBinary, &pubKey); err != nil {
        panic(err)
    } else if len(rest) != 0 {
        panic("rest is not nil")
    }

    fmt.Printf("key: %+v\n", pubKey)
}

打印出来：

key: {N:+102767083290202280873554060983826675083148443795791447833515664566475334389364583758312108980110921996262487865832851258326049062353432991986398760705560379825908169063986770245967781444794847106351934016144540466696422397564949226710181429429140226472206572796987719088983654589217713611861345869296293449649 E:65537}

您现在可以在包 rsa 函数中使用您的 public 密钥。

无法从 Golang 中的 iOS 解析 base64 DER 编码的 ASN.1 public 密钥

Could not parse base64 DER-encoded ASN.1 public key from iOS in Golang

rsa

go

public-key-encryption

ios

swift3