Attaching a usage plan to a public Api Gateway Endpoint - amazon-web-services

For learning purposes, I have developed a front-end application in Angular with AWS as back-end.
As this is a didactic project, I must prevent any possible costs explosion. Overall, for what concerns API Gateway calls.
At the moment, I have a single public GET endpoint for providing the information to the public homepage in the front-end.
I need to attach a usage plan to this endpoint for limiting the maximum number of calls to this endpoint. For example, max 10000 calls/week.
I already tried with an API-KEY:
Created the Usage Plan with "Quota: 10,000 requests per week"
Created the API KEY connected to the Usage Plan
Connected the API KEY to the authentication method of the endpoint
It works, but in this way I need to hard code the API KEY on the front-end.
I know that hard coding sensitive information on the front-end is a bad practice, but I thought that in this case the API KEY is needed only for connecting a Usage Plan, not for securing private information or operations. So I'm not sure if in this case it should be acceptable or not.
Is this solution safe, or could the same API KEY be used for other malicious purposes?
Are there any other solutions?

To add to the other answer, API Keys are not Authorization Tokens.
API Keys associated with Usage Plans are sent to the gateway on the x-api-key header (by default).
Tokens used by authorizers live on the standard Authorization header.
Use API Keys to set custom throttling and quotas for a particular caller, but you still need an Authorizer on any secure endpoints.
You can optionally set an API Key to be returned from the Authorizer when using a custom authorizer to be applied to the Usage Plan, which prevents you from having to distribute keys to clients in addition to their secrets.
APIG Key Source Docs

As the documentation says, generally you wouldn't want to rely on a hardcoded API key for authentication.
In addition, based on the information you provided, the usage plan limits are tied to the use by the user of the API key. So you could also set up throttling on the account or stage itself.
Finally, if it's possible, you could set up security group rules on your server or access control lists on your vpc that is serving your front end so that not everyone can access it.
Other ideas are to shut down the API gateway when you aren't using it and also rotate the API key frequently.
Obviously none of these are going to be enough if this were hosting sensitive information or doing anything remotely important. But as long as the only information in the client side is that API Key to access the API Gateway and that API Gateway itself doesn't interact with anything sensitive that's probably enough for a learning project.
But you should do all of this at your own risk as for all you know I'm the person who's going to try to hack you ;)

Related

How to give access to API behing AWS Api Gateway from our SDK

we use Aws Api Gateway to protect our apis.
We want to create an sdk for developers. The idea is to have In app purchase in their apps and call our apis in order to start payment.
We are trying to have a way to connect machine from machine. The first machine will be an sdk integrated in Android games and the second will be our back end protected by the api gateway.
The sdk should have a the authorization to consume the api.
Today we don't know how to do it, even after discussing with many architects.
The sdk is not going to have user and password, because it is not a user, so no way to generate the classic access token.
How could we achieve this use case ?
Thanks
The sdk should have a the authorization to consume the api. Today we don't know how to do it, even after discussing with many architects.
There are three possible ways to have a protected API Gateway. AWS Cognito and AWS Lambda. The third option, API Keys, is a little bit different than the previous two.
With Cognito, you create user pools and API Gateway automatically handles authorization when a request is received.
With Lambda, you create your own custom authorization logic.
I generally prefer the Lambda approach due to the ease of use but it depends on the use-case.
With the API Key option, you create API Keys for specific routes and API Gateway checks them through the request headers. I think any use-case that requires this can be handled with the Lambda option as well.
What you are describing doesn't sound difficult to achieve.
You will generate an API key and you will give them to the developers that will use your API.
In your SDK, you can accept the API key as an initialization parameter and provide it in the requests to API Gateway.

How to charge users by usage?

I’m building a service and I’m planning to charge a fixed price for each lambda call.
How to count requests per client if the lambda function being called is the same? I’m planning to pass a client id
You can use API Gateway Usage Plans for your requirement.
After you create, test, and deploy your APIs, you can use API Gateway usage plans to make them available as product offerings for your customers. You can configure usage plans and API keys to allow customers to access selected APIs at agreed-upon request rates and quotas that meet their business requirements and budget constraints. If desired, you can set default method-level throttling limits for an API or set throttling limits for individual API methods.
A usage plan specifies who can access one or more deployed API stages and methods—and also how much and how fast they can access them. The plan uses API keys to identify API clients and meters access to the associated API stages for each key. It also lets you configure throttling limits and quota limits that are enforced on individual client API keys.
Read this docs for more detail explanation.
You can use api gateway https://aws.amazon.com/api-gateway/
"Amazon API Gateway is a fully managed service that makes it easy for developers to create, publish, maintain, monitor, and secure APIs at any scale. APIs act as the "front door" for applications to access data, business logic, or functionality from your backend services."
It provides you with statistics about usage as well as different options like limit numbers of requests per api_key, etc

AWS API Gateway: Best practice for API key

What are best practices for API Keys within AWS API Gateway?
One APIKey per customer
OR
One APIKey per customer and API (so customers would have to use a different key for every API they use)
What are the Pros and Cons for each alternative?
Do we lose flexibility when customers have a single APIKey for every API?
I am always advising to have a single apikey for each client. That means single key for each Api. This way you will be able to easier diagnose which application/service is sending requests. Additionally you put yourself in a position that key rotation will only impact a single client. Furthermore you can make a great use of usage plans to throttle your clients one by one so that it is not going to impact other clients using the same API gateway.
In terms of flexibility, you as an owner of API gateway, your job is to protect your api so that each client can use it in a reasonable way up to predefined limits. Therefore, single key for each client is absolutely the right way to go.

How to add default throttled API key for unauthenticated API Gateway requests to prevent abuse?

I'd like to add a default throttled API key for unauthenticated requests to prevent abuse.
How would I do this in API Gateway?
EDIT
To make it clearer what I need, how do I transform a request in API Gateway? Is this possible?
I would say using Cognito is the best way of authorizing API gateway.
If you want a default API key then you can go for custom API gateway authorizer. Please have a look on official documentation for the same here
You need to store the API Key in the Server Side of your application and shouldn't expose it to the Client Side (Although API Key is not considered as a security token, it can be used by malicious party to call your API).
There are couple of options you have based on the nature of your application consuming the API.
If it is a single page web application where front-end is hosted in S3, you can use AWS CloudFront to store the API Key in headers and forward it to the API Gateway, while also serving the frontend through the same CloudFront distribution. This will also remove the cross origin resource sharing problem between your web application and API Gateway.
If you have a web server, you can store the API Key at Web Server and use to proxy request to the API Gateway while setting the API Key header value.
Note: Don't use API Key for authentication which is not recommended.
This is how I would solve it.
Create Usage Plan with the throttle, burst and max limit on the request allowed.
http://docs.aws.amazon.com/AWSJavaScriptSDK/latest/AWS/APIGateway.html#createUsagePlan-property
API Key:
Create API Key (createApiKey) and associate it (createUsagePlanKey) with Usage Plan already defined. That will allow the limit defined for the requests received.
http://docs.aws.amazon.com/AWSJavaScriptSDK/latest/AWS/APIGateway.html#createApiKey-property
http://docs.aws.amazon.com/AWSJavaScriptSDK/latest/AWS/APIGateway.html#createUsagePlanKey-property
Have a separate lambda to monitor the Generated API-Keys and cleanup once it is expired, so you will not flood API-Gateway with unused keys.
If you take it to CloudFront, you can create Self Signed URL, that will be valid for a given period of time. After that time limit URL will be invalid. This is to keep yourself time-limited for the user, so within the given timelimit, what resource they can access.
One more usecase, we worked on, you can authenticate the user only on certain urls with custom Authorizer. Any other urls that get invokes, will return unauthorized without any additional code.
Hope it helps.

Monitor API Gateway APIs based on API key

How can I monitor my Amazon API Gateway APIs API key wise?
Currently it is showing data for all API keys, but I want to display API calls, 5xx errors, 4xx errors etc for particular API key.
If you're looking at monitoring the API on X-Api-Key header level, it looks like this is currently not possible. I'm guessing you'd have to do it yourself on the application layer, which should be relatively easy if you're using Lambda. Your question brings up another question: Does it really make sense to monitor individual API keys when errors are associated with particular API deployment/version?
If you'd like to monitor per-user use, you need to make use of IAM credentials with your API and CloudTrail to monitor requests made with specific credentials. You can find more info on the API Gateway CloudTrail integration page.
API Gateway doesn't (yet) offer first-class support for API Key metrics. As #kixorz mentioned, you could implement this in the application layer for the time being (for example using Lambda and CloudWatch).