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/AWS1/IF_CGP=>RESPONDTOAUTHCHALLENGE()

About RespondToAuthChallenge

Some API operations in a user pool generate a challenge, like a prompt for an MFA code, for device authentication that bypasses MFA, or for a custom authentication challenge. A RespondToAuthChallenge API request provides the answer to that challenge, like a code or a secure remote password (SRP). The parameters of a response to an authentication challenge vary with the type of challenge.

For more information about custom authentication challenges, see Custom authentication challenge Lambda triggers.

Amazon Cognito doesn't evaluate Identity and Access Management (IAM) policies in requests for this API operation. For this operation, you can't use IAM credentials to authorize requests, and you can't grant IAM permissions in policies. For more information about authorization models in Amazon Cognito, see Using the Amazon Cognito user pools API and user pool endpoints.

This action might generate an SMS text message. Starting June 1, 2021, US telecom carriers require you to register an origination phone number before you can send SMS messages to US phone numbers. If you use SMS text messages in Amazon Cognito, you must register a phone number with Amazon Pinpoint. Amazon Cognito uses the registered number automatically. Otherwise, Amazon Cognito users who must receive SMS messages might not be able to sign up, activate their accounts, or sign in.

If you have never used SMS text messages with Amazon Cognito or any other Amazon Web Services service, Amazon Simple Notification Service might place your account in the SMS sandbox. In sandbox mode , you can send messages only to verified phone numbers. After you test your app while in the sandbox environment, you can move out of the sandbox and into production. For more information, see SMS message settings for Amazon Cognito user pools in the Amazon Cognito Developer Guide.

Method Signature

IMPORTING

Required arguments:

iv_clientid TYPE /AWS1/CGPCLIENTIDTYPE /AWS1/CGPCLIENTIDTYPE

The ID of the app client where the user is signing in.

iv_challengename TYPE /AWS1/CGPCHALLENGENAMETYPE /AWS1/CGPCHALLENGENAMETYPE

The name of the challenge that you are responding to.

You can't respond to an ADMIN_NO_SRP_AUTH challenge with this operation.

Possible challenges include the following:

All of the following challenges require USERNAME and, when the app client has a client secret, SECRET_HASH in the parameters. Include a DEVICE_KEY for device authentication.

  • WEB_AUTHN: Respond to the challenge with the results of a successful authentication with a WebAuthn authenticator, or passkey, as CREDENTIAL. Examples of WebAuthn authenticators include biometric devices and security keys.

  • PASSWORD: Respond with the user's password as PASSWORD.

  • PASSWORD_SRP: Respond with the initial SRP secret as SRP_A.

  • SELECT_CHALLENGE: Respond with a challenge selection as ANSWER. It must be one of the challenge types in the AvailableChallenges response parameter. Add the parameters of the selected challenge, for example USERNAME and SMS_OTP.

  • SMS_MFA: Respond with the code that your user pool delivered in an SMS message, as SMS_MFA_CODE

  • EMAIL_MFA: Respond with the code that your user pool delivered in an email message, as EMAIL_MFA_CODE

  • EMAIL_OTP: Respond with the code that your user pool delivered in an email message, as EMAIL_OTP_CODE .

  • SMS_OTP: Respond with the code that your user pool delivered in an SMS message, as SMS_OTP_CODE.

  • PASSWORD_VERIFIER: Respond with the second stage of SRP secrets as PASSWORD_CLAIM_SIGNATURE, PASSWORD_CLAIM_SECRET_BLOCK, and TIMESTAMP.

  • CUSTOM_CHALLENGE: This is returned if your custom authentication flow determines that the user should pass another challenge before tokens are issued. The parameters of the challenge are determined by your Lambda function and issued in the ChallengeParameters of a challenge response.

  • DEVICE_SRP_AUTH: Respond with the initial parameters of device SRP authentication. For more information, see Signing in with a device.

  • DEVICE_PASSWORD_VERIFIER: Respond with PASSWORD_CLAIM_SIGNATURE, PASSWORD_CLAIM_SECRET_BLOCK, and TIMESTAMP after client-side SRP calculations. For more information, see Signing in with a device.

  • NEW_PASSWORD_REQUIRED: For users who are required to change their passwords after successful first login. Respond to this challenge with NEW_PASSWORD and any required attributes that Amazon Cognito returned in the requiredAttributes parameter. You can also set values for attributes that aren't required by your user pool and that your app client can write.

    Amazon Cognito only returns this challenge for users who have temporary passwords. When you create passwordless users, you must provide values for all required attributes.

    In a NEW_PASSWORD_REQUIRED challenge response, you can't modify a required attribute that already has a value. In AdminRespondToAuthChallenge or RespondToAuthChallenge, set a value for any keys that Amazon Cognito returned in the requiredAttributes parameter, then use the AdminUpdateUserAttributes or UpdateUserAttributes API operation to modify the value of any additional attributes.

  • MFA_SETUP: For users who are required to setup an MFA factor before they can sign in. The MFA types activated for the user pool will be listed in the challenge parameters MFAS_CAN_SETUP value.

    To set up time-based one-time password (TOTP) MFA, use the session returned in this challenge from InitiateAuth or AdminInitiateAuth as an input to AssociateSoftwareToken. Then, use the session returned by VerifySoftwareToken as an input to RespondToAuthChallenge or AdminRespondToAuthChallenge with challenge name MFA_SETUP to complete sign-in.

    To set up SMS or email MFA, collect a phone_number or email attribute for the user. Then restart the authentication flow with an InitiateAuth or AdminInitiateAuth request.

Optional arguments:

iv_session TYPE /AWS1/CGPSESSIONTYPE /AWS1/CGPSESSIONTYPE

The session identifier that maintains the state of authentication requests and challenge responses. If an AdminInitiateAuth or AdminRespondToAuthChallenge API request results in a determination that your application must pass another challenge, Amazon Cognito returns a session with other challenge parameters. Send this session identifier, unmodified, to the next AdminRespondToAuthChallenge request.

it_challengeresponses TYPE /AWS1/CL_CGPCHALLENGERSPSTYP00=>TT_CHALLENGERESPONSESTYPE TT_CHALLENGERESPONSESTYPE

The responses to the challenge that you received in the previous request. Each challenge has its own required response parameters. The following examples are partial JSON request bodies that highlight challenge-response parameters.

You must provide a SECRET_HASH parameter in all challenge responses to an app client that has a client secret. Include a DEVICE_KEY for device authentication.
SELECT_CHALLENGE

"ChallengeName": "SELECT_CHALLENGE", "ChallengeResponses": { "USERNAME": "[username]", "ANSWER": "[Challenge name]"}

Available challenges are PASSWORD, PASSWORD_SRP, EMAIL_OTP, SMS_OTP, and WEB_AUTHN.

Complete authentication in the SELECT_CHALLENGE response for PASSWORD, PASSWORD_SRP, and WEB_AUTHN:

  • "ChallengeName": "SELECT_CHALLENGE", "ChallengeResponses": { "ANSWER": "WEB_AUTHN", "USERNAME": "[username]", "CREDENTIAL": "[AuthenticationResponseJSON]"}

    See AuthenticationResponseJSON.

  • "ChallengeName": "SELECT_CHALLENGE", "ChallengeResponses": { "ANSWER": "PASSWORD", "USERNAME": "[username]", "PASSWORD": "[password]"}

  • "ChallengeName": "SELECT_CHALLENGE", "ChallengeResponses": { "ANSWER": "PASSWORD_SRP", "USERNAME": "[username]", "SRP_A": "[SRP_A]"}

For SMS_OTP and EMAIL_OTP, respond with the username and answer. Your user pool will send a code for the user to submit in the next challenge response.

  • "ChallengeName": "SELECT_CHALLENGE", "ChallengeResponses": { "ANSWER": "SMS_OTP", "USERNAME": "[username]"}

  • "ChallengeName": "SELECT_CHALLENGE", "ChallengeResponses": { "ANSWER": "EMAIL_OTP", "USERNAME": "[username]"}

WEB_AUTHN

"ChallengeName": "WEB_AUTHN", "ChallengeResponses": { "USERNAME": "[username]", "CREDENTIAL": "[AuthenticationResponseJSON]"}

See AuthenticationResponseJSON.

PASSWORD

"ChallengeName": "PASSWORD", "ChallengeResponses": { "USERNAME": "[username]", "PASSWORD": "[password]"}

PASSWORD_SRP

"ChallengeName": "PASSWORD_SRP", "ChallengeResponses": { "USERNAME": "[username]", "SRP_A": "[SRP_A]"}

SMS_OTP

"ChallengeName": "SMS_OTP", "ChallengeResponses": {"SMS_OTP_CODE": "[code]", "USERNAME": "[username]"}

EMAIL_OTP

"ChallengeName": "EMAIL_OTP", "ChallengeResponses": {"EMAIL_OTP_CODE": "[code]", "USERNAME": "[username]"}

SMS_MFA

"ChallengeName": "SMS_MFA", "ChallengeResponses": {"SMS_MFA_CODE": "[code]", "USERNAME": "[username]"}

PASSWORD_VERIFIER

This challenge response is part of the SRP flow. Amazon Cognito requires that your application respond to this challenge within a few seconds. When the response time exceeds this period, your user pool returns a NotAuthorizedException error.

"ChallengeName": "PASSWORD_VERIFIER", "ChallengeResponses": {"PASSWORD_CLAIM_SIGNATURE": "[claim_signature]", "PASSWORD_CLAIM_SECRET_BLOCK": "[secret_block]", "TIMESTAMP": [timestamp], "USERNAME": "[username]"}

CUSTOM_CHALLENGE

"ChallengeName": "CUSTOM_CHALLENGE", "ChallengeResponses": {"USERNAME": "[username]", "ANSWER": "[challenge_answer]"}

NEW_PASSWORD_REQUIRED

"ChallengeName": "NEW_PASSWORD_REQUIRED", "ChallengeResponses": {"NEW_PASSWORD": "[new_password]", "USERNAME": "[username]"}

To set any required attributes that InitiateAuth returned in an requiredAttributes parameter, add "userAttributes.[attribute_name]": "[attribute_value]". This parameter can also set values for writable attributes that aren't required by your user pool.

In a NEW_PASSWORD_REQUIRED challenge response, you can't modify a required attribute that already has a value. In AdminRespondToAuthChallenge or RespondToAuthChallenge, set a value for any keys that Amazon Cognito returned in the requiredAttributes parameter, then use the AdminUpdateUserAttributes or UpdateUserAttributes API operation to modify the value of any additional attributes.
SOFTWARE_TOKEN_MFA

"ChallengeName": "SOFTWARE_TOKEN_MFA", "ChallengeResponses": {"USERNAME": "[username]", "SOFTWARE_TOKEN_MFA_CODE": [authenticator_code]}

DEVICE_SRP_AUTH

"ChallengeName": "DEVICE_SRP_AUTH", "ChallengeResponses": {"USERNAME": "[username]", "DEVICE_KEY": "[device_key]", "SRP_A": "[srp_a]"}

DEVICE_PASSWORD_VERIFIER

"ChallengeName": "DEVICE_PASSWORD_VERIFIER", "ChallengeResponses": {"DEVICE_KEY": "[device_key]", "PASSWORD_CLAIM_SIGNATURE": "[claim_signature]", "PASSWORD_CLAIM_SECRET_BLOCK": "[secret_block]", "TIMESTAMP": [timestamp], "USERNAME": "[username]"}

MFA_SETUP

"ChallengeName": "MFA_SETUP", "ChallengeResponses": {"USERNAME": "[username]"}, "SESSION": "[Session ID from VerifySoftwareToken]"

SELECT_MFA_TYPE

"ChallengeName": "SELECT_MFA_TYPE", "ChallengeResponses": {"USERNAME": "[username]", "ANSWER": "[SMS_MFA|EMAIL_MFA|SOFTWARE_TOKEN_MFA]"}

For more information about SECRET_HASH, see Computing secret hash values. For information about DEVICE_KEY, see Working with user devices in your user pool.

io_analyticsmetadata TYPE REF TO /AWS1/CL_CGPALYSMETADATATYPE /AWS1/CL_CGPALYSMETADATATYPE

Information that supports analytics outcomes with Amazon Pinpoint, including the user's endpoint ID. The endpoint ID is a destination for Amazon Pinpoint push notifications, for example a device identifier, email address, or phone number.

io_usercontextdata TYPE REF TO /AWS1/CL_CGPUSERCTXDATATYPE /AWS1/CL_CGPUSERCTXDATATYPE

Contextual data about your user session like the device fingerprint, IP address, or location. Amazon Cognito threat protection evaluates the risk of an authentication event based on the context that your app generates and passes to Amazon Cognito when it makes API requests.

For more information, see Collecting data for threat protection in applications.

it_clientmetadata TYPE /AWS1/CL_CGPCLIENTMETTYPE_W=>TT_CLIENTMETADATATYPE TT_CLIENTMETADATATYPE

A map of custom key-value pairs that you can provide as input for any custom workflows that this action triggers.

You create custom workflows by assigning Lambda functions to user pool triggers. When you use the RespondToAuthChallenge API action, Amazon Cognito invokes any functions that are assigned to the following triggers: post authentication, pre token generation, define auth challenge, create auth challenge, and verify auth challenge. When Amazon Cognito invokes any of these functions, it passes a JSON payload, which the function receives as input. This payload contains a clientMetadata attribute, which provides the data that you assigned to the ClientMetadata parameter in your RespondToAuthChallenge request. In your function code in Lambda, you can process the clientMetadata value to enhance your workflow for your specific needs.

For more information, see Using Lambda triggers in the Amazon Cognito Developer Guide.

When you use the ClientMetadata parameter, note that Amazon Cognito won't do the following:

  • Store the ClientMetadata value. This data is available only to Lambda triggers that are assigned to a user pool to support custom workflows. If your user pool configuration doesn't include triggers, the ClientMetadata parameter serves no purpose.

  • Validate the ClientMetadata value.

  • Encrypt the ClientMetadata value. Don't send sensitive information in this parameter.

RETURNING

oo_output TYPE REF TO /aws1/cl_cgprespondtoauthcha01 /AWS1/CL_CGPRESPONDTOAUTHCHA01

Domain /AWS1/RT_ACCOUNT_ID
Primitive Type NUMC

Examples

Syntax Example

This is an example of the syntax for calling the method. It includes every possible argument and initializes every possible value. The data provided is not necessarily semantically accurate (for example the value "string" may be provided for something that is intended to be an instance ID, or in some cases two arguments may be mutually exclusive). The syntax shows the ABAP syntax for creating the various data structures.

DATA(lo_result) = lo_client->/aws1/if_cgp~respondtoauthchallenge(
  io_analyticsmetadata = new /aws1/cl_cgpalysmetadatatype( |string| )
  io_usercontextdata = new /aws1/cl_cgpuserctxdatatype(
    iv_encodeddata = |string|
    iv_ipaddress = |string|
  )
  it_challengeresponses = VALUE /aws1/cl_cgpchallengerspstyp00=>tt_challengeresponsestype(
    (
      VALUE /aws1/cl_cgpchallengerspstyp00=>ts_challengerspstype_maprow(
        key = |string|
        value = new /aws1/cl_cgpchallengerspstyp00( |string| )
      )
    )
  )
  it_clientmetadata = VALUE /aws1/cl_cgpclientmettype_w=>tt_clientmetadatatype(
    (
      VALUE /aws1/cl_cgpclientmettype_w=>ts_clientmetadatatype_maprow(
        key = |string|
        value = new /aws1/cl_cgpclientmettype_w( |string| )
      )
    )
  )
  iv_challengename = |string|
  iv_clientid = |string|
  iv_session = |string|
).

This is an example of reading all possible response values

lo_result = lo_result.
IF lo_result IS NOT INITIAL.
  lv_challengenametype = lo_result->get_challengename( ).
  lv_sessiontype = lo_result->get_session( ).
  LOOP AT lo_result->get_challengeparameters( ) into ls_row.
    lv_key = ls_row-key.
    lo_value = ls_row-value.
    IF lo_value IS NOT INITIAL.
      lv_stringtype = lo_value->get_value( ).
    ENDIF.
  ENDLOOP.
  lo_authenticationresulttyp = lo_result->get_authenticationresult( ).
  IF lo_authenticationresulttyp IS NOT INITIAL.
    lv_tokenmodeltype = lo_authenticationresulttyp->get_accesstoken( ).
    lv_integertype = lo_authenticationresulttyp->get_expiresin( ).
    lv_stringtype = lo_authenticationresulttyp->get_tokentype( ).
    lv_tokenmodeltype = lo_authenticationresulttyp->get_refreshtoken( ).
    lv_tokenmodeltype = lo_authenticationresulttyp->get_idtoken( ).
    lo_newdevicemetadatatype = lo_authenticationresulttyp->get_newdevicemetadata( ).
    IF lo_newdevicemetadatatype IS NOT INITIAL.
      lv_devicekeytype = lo_newdevicemetadatatype->get_devicekey( ).
      lv_stringtype = lo_newdevicemetadatatype->get_devicegroupkey( ).
    ENDIF.
  ENDIF.
ENDIF.