I am trying to reduce the number of login a user needs to gain access to multiple application. I have aws ad set that provides me authentication to vpn and mail client. No i need a website that I can use ad creds to allow users to upload,dowload and list files in an s3 bucket. it seems like i can do this with cognito maybe but the aws ad doesn't seem to support SAML/ADFS that allows you to link cognito to aws ad. Is there something I am missing
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I'm developing a mobile app that must access some AWS resources, so it needs authentication to AWS endpoint. The app doesn't manage users (sign-in, sign-out, register and so on).
My first solution was to create a IAM user dedicated to the mobile app and embed its credentials in the mobile app code. The app authenticate itself to AWS using the embedded credentials. It works, however AWS suggests to avoid embedding credentials directly in the app.
I think a better solution is Cognito. Because I don't need users management, I should use unauthenticated (guest) identity to request temporary AWS credentials.
However I don't understand why a guest Cognito identity is more secure than an embedded credentials. The mobile app receive a temporary AWS credentials by sending a Cognito Identity Pool ID, that is a long-term "number" embedded in the mobile app. If someone is able to find this Identity Pool ID, she can receive AWS credentials and access AWS resources as my official mobile app. It seems there's no difference between embedded AWS long-term credentials and huest Cognito access.
Why Cognito solution is better than embedded AWS credentials?
If you are creating unauthenticated access using identity pool, you are allowing public to access your AWS resources. Make sure you write your policy carefully and it won't matter if you use a single IAM user or cognito unauthenticated access as far as security is concerned.
Using federated identity will provide you benefits like getting statistics on usage and adding triggers to events. Also keep in mind that creating a single IAM user and then allowing multiple people to use these credentials is a "hack" way of doing what cognito federated unauthenticated idenity was designed to do. You might run into unexpected complications later if AWS decides to throttle this behavior of IAM.
We're building an application using AWS App Sync, we're still in a very early stage.
Our application has a restricted area, through user sign-in, which is being managed via aws cognito users pool. And this is fine.
We're having issues on the public area which doesn't require any authentication.
How can we protect these public endpoints?
We're having some doubts about hard coding the api key (that we know can be rotated), is it a good practice (documentation page says that it isn't ideal for production)?
Is there any way to authorise the origin? (aka, any request coming from www.foobar.baz is ok)
I would suggest using Amazon Cognito Federated Identity to control authenticated and unauthenticated access to the api. In order to do use Amazon Cognito Federated Identity with AWS AppSync, you need to use AWS IAM based authorization.
For the authenticated access you can use Amazon Cognito User Pools and federated to Amazon Cognito Federated Identity and since the federated identity can also allow for unauthenticated users it will allow you to control some api's which can be made public via an IAM policy.
For more information please read the AWS IAM Section of our security guide here
Under your AppSync app's Settings menu, where you set the User Pool Configuration, there is an option to set a default action. You can change this to DENY and all unauthenticated requests will be rejected. The alternative approach is to ALLOW everything, and manually add #aws_auth directives to every query/mutation/subscription field that you care about restricting.
I would like to create my own HTML page to allow users to login using the IAM credentials. I could not find any reference how to do it without getting the credential token first. I would like to host this on an AWS S3 bucket.
A combination of Javascript web app and using Javascript SDK for AWS cognito could work to serve your purposes.
Example of creating a page using Javascript to log in users with Facebook login and access an S3 bucket.
http://docs.aws.amazon.com/sdk-for-javascript/v2/developer-guide/getting-started-browser.html
https://aws.amazon.com/developers/getting-started/browser/
Using Cognito
Amazon Cognito lets you easily add user sign-up and sign-in to your mobile and web apps. With Amazon Cognito, you also have the options to authenticate users through social identity providers such as Facebook, Twitter, or Amazon, with SAML identity solutions, or by using your own identity system. In addition, Amazon Cognito enables you to save data locally on users devices, allowing your applications to work even when the devices are offline. You can then synchronize data across users devices so that their app experience remains consistent regardless of the device they use.
https://aws.amazon.com/cognito/
AWS S3 documentation clearly explains, it's not possible.
You can host a static website on Amazon S3. On a static website,
individual web pages include static content. They may also contain
client-side scripts. By contrast, a dynamic website relies on
server-side processing, including server-side scripts such as PHP,
JSP, or ASP.NET. Amazon S3 does not support server-side scripting.
If you mean, you would like to grant access to HTML content for only certain users without their IAM, you could explore S3 pre-signed object URL option.
IAM username/password credentials are only for use with the AWS console.
There is no exposed API that you can use to validate IAM credentials.
Q: Is there an authentication API to verify IAM user sign-ins?
No. There is no programmatic way to verify user sign-ins.
https://aws.amazon.com/iam/faqs/
I am building web application based on microservice architecture. At this moment I am considering few ways of user authentication flow. I predict following, example user roles:
admin - is able to create content, upload files etc (admin account can be created only by another admin)
unauthorized user - can view content
authorized user - can comment content
Here is, how I was thinking about authentication flow so far:
authentication service - have access to DB with users credentials and permissions
api gateway - retrieve requests from user, check if user is logged in (ie verifies OAuth2 access token with auth service) and transfer flow to other services based on user request (attaching JWT token with some basic user info)
another service - accept only requests from api gateway, and trusts user data from JWT token (does not need to connect with auth service to get information about user).
After deploying some stuff on AWS infrastructure my way of thinking have changed a little bit. As far as I understand AWS products (Lambda - serverless applications and API gateway), I should implement authentication flow as follows:
authentication service - gets request from user, retrieve data from dynamoDB and provide user cookie with JWT signed by private key
any other service - retrieves request with JWT token, verifies signature using public key, and perform some action.
And now the question comes:
How deos AWS Cognito fits here? Is it something useful for me? As far as I understand, Cognito simplifies flow of authenticating users via 3rd parties (facebook, twitter etc. etc.). Does AWS Cognito serves login page, separated from my application, or it is only background/webservices impelementation?
So far I am thinking about Cognito as a replacement for my authentication service - any of my services, should impelemnt Cognito authentication flow provided by SDK from amazon, and my static website would implement JavaScript SDK for user login/register. Am I right?
First of all AWS Cognito consists of two services.
AWS Cognito UserPools (Which is the Identity Provider) - This is the service where you can create the users and manage their credentials with other policies. It can also provide the login screen where we can customize the logo and look and feel so that it can become a plug and play Login service. Then it is also possible to configure the authentication flow (For example to make the service as an OpenIDConnect authentication provider so that it will return a JWT token once user logs in). It is also possible to connect Social Identities (Facebook, Google & etc.) and SAML.
AWS Cognito Federated Identities (Identity Federation to grant users access AWS Services) - This service is capable of accepting AWS Cognito UserPool Token or direct access from other providers where we can federate the access to AWS resources. For example, AWS Cognito Federated Identities can grant temporal access to a User, Authenticated from another provider (e.g; AWS Cognito UserPools) to upload files to S3.
For more details refer the article The Difference Between AWS Cognito UserPools and Federated Identities?.
So coming back to your questions,
So far I am thinking about Cognito as a replacement for my
authentication service?
you can use AWS Cognito UserPools authentication service to issue JWT tokens and validate the token in AWS Lambda Custom Authorizer at your other service endpoints. This is also the place where you can do Authorization.
My static website would implement JavaScript SDK for user
login/register. Am I right?
Not necessarily. If you use AWS Cognito UserPools Hosted UI, you will get Login, Signup, Password Change, Confirmation pages, by default along with auto redirection for Federated Identities (Based on the configurations) such as Facebook, Google or Corporate Credentials like Office365. Although the customization is limited, you should be able to add your own logo and change the background color of these screens. If you plan to implement this by your self, then you can use AWS SDKs to implement these screens.
For more details on the serverless architecture refer Full Stack Serverless Web Apps with AWS.
I have a client that has an on-prem AD Server... I am developing an application running through API Gateway that will use a custom authorizer to authorize the endpoints. The on-prem AD server will be used to authenticate internal users, thinking about deploying an AD server in AWS for external users and using some sort of "link" between the two to connect them.
I want to query AD to authenticate the users and then get their IAM roles to allow access the API. Is this a good implementation?
If you are able to run AD FS and expose it to Cognito, I would suggest looking into using Cognito Federated Identity and setting the Method to require AWS_IAM authorization. Here is a link to the docs for AD FS:
https://aws.amazon.com/blogs/mobile/announcing-saml-support-for-amazon-cognito/
Alternatively, if you can't run AD FS and are running AWS Directory Service for Microsoft Active Directory for some other purpose, you could create a trust relationship to your on-prem AD through a direct connect / VPN. You could then create a service which took the AD credentials and authenticated the user via LDAP (lambda function configured to used with a VPC). Finally a custom authorizer could be created that validated the token for subsequent calls and return an appropriate IAM policy.