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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

Source: R/cognitoidentityprovider_operations.R
cognitoidentityprovider_admin_respond_to_auth_challenge.Rd

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. An admin_respond_to_auth_challenge 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.

See https://www.paws-r-sdk.com/docs/cognitoidentityprovider_admin_respond_to_auth_challenge/ for full documentation.

Usage

cognitoidentityprovider_admin_respond_to_auth_challenge(
  UserPoolId,
  ClientId,
  ChallengeName,
  ChallengeResponses = NULL,
  Session = NULL,
  AnalyticsMetadata = NULL,
  ContextData = NULL,
  ClientMetadata = NULL
)

Arguments

UserPoolId

[required] The ID of the user pool where you want to respond to an authentication challenge.

ClientId

[required] The ID of the app client where you initiated sign-in.

ChallengeName

[required] The name of the challenge that you are responding to.

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 admin_respond_to_auth_challenge or respond_to_auth_challenge, set a value for any keys that Amazon Cognito returned in the requiredAttributes parameter, then use the admin_update_user_attributes or update_user_attributes 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 initiate_auth or admin_initiate_auth as an input to associate_software_token. Then, use the session returned by verify_software_token as an input to respond_to_auth_challenge or admin_respond_to_auth_challenge 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 initiate_auth or admin_initiate_auth request.

ChallengeResponses

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 initiate_auth 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 admin_respond_to_auth_challenge or respond_to_auth_challenge, set a value for any keys that Amazon Cognito returned in the requiredAttributes parameter, then use the admin_update_user_attributes or update_user_attributes 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.

Session

The session identifier that maintains the state of authentication requests and challenge responses. If an admin_initiate_auth or admin_respond_to_auth_challenge 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 admin_respond_to_auth_challenge request.

AnalyticsMetadata

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.

ContextData

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.

ClientMetadata

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 Amazon Cognito invokes any of these functions, it passes a JSON payload, which the function receives as input. This payload contains a clientMetadata attribute that provides the data that you assigned to the ClientMetadata parameter in your request. In your function code, you can process the clientMetadata value to enhance your workflow for your specific needs.

To review the Lambda trigger types that Amazon Cognito invokes at runtime with API requests, see Connecting API actions to 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.