# MIT Kerberos Documentation

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# KRB5_RESPONDER_QUESTION_OTP

`KRB5_RESPONDER_QUESTION_OTP`

OTP responder question.

The OTP responder question is asked when the KDC indicates that an OTP value is required in order to complete the authentication. The JSON format of the challenge is:

    {
      "service": <string (optional)>,
      "tokenInfo": [
        {
          "flags":     <number>,
          "vendor":    <string (optional)>,
          "challenge": <string (optional)>,
          "length":    <number (optional)>,
          "format":    <number (optional)>,
          "tokenID":   <string (optional)>,
          "algID":     <string (optional)>,
        },
        ...
      ]
    }

The answer to the question MUST be JSON formatted:

    {
      "tokeninfo": <number>,
      "value":     <string (optional)>,
      "pin":       <string (optional)>,
    }

For more detail, please see RFC 6560.

`KRB5_RESPONDER_QUESTION_OTP` | `"otp"`