A lot of JWKS queries on apigateway.googleapis.com - google-cloud-platform

I've configured a Google API gateway in front of our Cloud Run services with JWT authentication as a custom security definition. It works but I'm seeing a lot of outgoing queries. I can see multiple (2-4) log entries every five minutes for the same endpoint (logname: apigateway.googleapis.com/jwks_queries). Is there a way to further debug this or to allow some caching on this. I'm assuming this is causing some delay on our API requests.

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Setting Cloud Monitoring uptime checks for non publicly accessible backends

I'm having some trouble setting uptime checks for some Cloud Run services that don't allow unauthenticated invocations.
For context, I'm using Cloud Endpoints + ESPv2 as an API gateway that's connected to a few Cloud Run services.
The ESPv2 container/API gateway allows unauthenticated invocations, but the underlying Cloud Run services do not (since requests to these backends flow via the API gateway).
Each Cloud Run service has an internal health check endpoint that I'd like to hit periodically via Cloud Monitoring uptime checks.
This serves the purpose of ensuring that my Cloud Run services are healthy, but also gives the added benefit of reduced cold boot times as the containers are kept 'warm'
However, since the protected Cloud Run services expect a valid authorisation header all of the requests from Cloud Monitoring fail with a 403.
From the Cloud Monitoring UI, it looks like you can only configure a static auth header, which won't work in this case. I need to be able to dynamically create an auth header per request sent from Cloud Monitoring.
I can see that Cloud Scheduler supports this already. I have a few internal endpoints on the Cloud Run services (that aren't exposed via the API gateway) that are hit via Cloud Scheduler, and I am able to configure an OIDC auth header on each request. Ideally, I'd be able to do the same with Cloud Monitoring.
I can see a few workarounds for this, but all of them are less than ideal:
Allow unauthenticated invocations for the underlying Cloud Run services. This will make my internal services publicly accessible and then I will have to worry about handling auth within each service.
Expose the internal endpoints via the API gateway/ESPv2. This is effectively the same as the previous workaround.
Expose the internal endpoints via the API gateway/ESPv2 AND configure some sort of auth. This sort of works but at the time of writing the only auth methods supported by ESPv2 are API Keys and JWT. JWT is already out of the question but I guess an API key would work. Again, this requires a bit of set up which I'd rather avoid if possible.
Would appreciate any thought/advice on this.
Thanks!
This simple solution may work on your use case as it is easier to just use a TCP uptime check on port 443:
Create your own Cloud Run service using https://cloud.google.com/run/docs/quickstarts/prebuilt-deploy.
Create a new uptime check on TCP port 443 Cloud Run URL.
Wait a couple of minutes.
Location results: All locations passed
Virginia OK
Oregon OK
Iowa OK
Belgium OK
Singapore OK
Sao Paulo OK
I would also like to advise that Cloud Run is a Google fully managed product and it has a 99.95 % monthly up time SLA, with no recent incidents in the past few months, but proactively monitoring this on your end is a very good thing too.

How to set quota for CORS preflight requests with AWS API Gateway

I'm building a serverless application with AWS Lambda and API Gateway. In order to prevent DDOS attacks doing a large number of requests costing me lots of money, I've set up a usage plan with a request quota (e.g. 10K requests/month). This requires an API key to be passed as header by callers.
This seemingly works well, but I also need to enable CORS for this service. For that I need to allow for an unauthorized OPTIONS request ("CORS preflight" request) as browsers don't support sending any special header there. But then I can't seem to find a way for enforcing a quota and I'm back to square one: an uncontrolled number of those requests could cost an unforeseeable amount of money. Is there any way to exclude this possibility?
To enforce a quota on OPTIONS requests, create a web ACL in AWS WAF & associate it to a stage of your API in API Gateway. Add a rate-based rule in the web ACL that blocks all OPTIONS requests beyond the rate limit you specify. Rules in web ACLs can be configured specifically for this, as shown below:
For a screenshot-guided tutorial of this entire process, see my blog post.
You are not paying for any unauthorized calls to API-Gateway.
AWS is picking up this charge.
You are paying after the request is authorized and only if it does not exceed your usage plan.
So if somebody is doing a DDOS on your API without authentication it is free of charge.
If somebody is doing a DDOS with a valid api key you will only pay until your usage plan is exceeded.
Find more information here.
Requests are not charged for authorization and authentication
failures.
Calls to methods that require API keys are not charged when API keys
are missing or invalid.
API Gateway-throttled requests are not charged when the request rate
or burst rate exceeds the preconfigured limits.
Usage plan-throttled requests are not charged when rate limits or
quota exceed the preconfigured limits.
So make sure to have authentication enabled on your API and a usage plan in place for all the authenticated requests.

How do we address/what are good practices for "serverless" resource abuse?

If I create a public endpoint using AWS API Gateway, the entire world could access it. This would be a problem because the end point would trigger an AWS Lambda function. If we assume that I can't query a data source to determine the frequency that the incoming IP address queried the resource in the past, what would be the best practice for protecting this end point from abuse? Do I have any other security options?
I realize I could use a reCaptcha but this would still invoke the AWS Lambda function and would incur costs if done a million times over a short window of time.
A very simple way of protecting your API gateway
Use AWS Cloudfront with TTL 0 and pass custom headers from AWS Cloudfront to API gateway
Use AWS WAF with AWS Cloudfront
AWS API Gateway also handles some basic level of DDOS attacks.
Kindly also view these blogs for securing AWS API Gateway
https://aws.amazon.com/blogs/compute/protecting-your-api-using-amazon-api-gateway-and-aws-waf-part-i/
https://aws.amazon.com/blogs/compute/protecting-your-api-using-amazon-api-gateway-and-aws-waf-part-2/
You are probably looking for throttling limit configuration or usage plan definition:
To prevent your API from being overwhelmed by too many requests,
Amazon API Gateway throttles requests to your API using the token
bucket algorithm, where a token counts for a request. Specifically,
API Gateway sets a limit on a steady-state rate and a burst of request
submissions against all APIs in your account. In the token bucket
algorithm, the burst is the maximum bucket size.
When request submissions exceed the steady-state request rate and
burst limits, API Gateway fails the limit-exceeding requests and
returns 429 Too Many Requests error responses to the client. Upon
catching such exceptions, the client can resubmit the failed requests
in a rate-limiting fashion, while complying with the API Gateway
throttling limits.
As an API developer, you can set the limits for individual API stages
or methods to improve overall performance across all APIs in your
account. Alternatively, you can enable usage plans to restrict client
request submissions to within specified request rates and quotas. This
restricts the overall request submissions so that they don't go
significantly past the account-level throttling limits.
References:
https://docs.aws.amazon.com/apigateway/latest/developerguide/api-gateway-request-throttling.html
https://docs.aws.amazon.com/apigateway/latest/developerguide/api-gateway-create-usage-plans-with-console.html#api-gateway-usage-plan-create

Prevent AWS Lambda flooding

I'm considering about moving my service from a VPS to AWS Lambda + DynamoDB to use it as a FaaS, because it's basically 2 API GET calls that fetch info from the database and serve it, and the normal use of those API calls are really rare (about 50 times a week)
But it makes me wonder... As I can't setup a limit on how many calls I want to serve each month, some attacker could theoretically flood my service by calling it a couple thousands times a day and make my AWS bill extremely expensive. Setting up a limit per month wouldn't be a nice idea either, because the attacker could flood the first day and I won't have more requests to serve. The ideal thing would be to set up a limit on request rate per client.
Anyone knows how could I protect it? I've seen that AWS also offers a Firewall, but that's for CloudFront. Isn't there any way to make it work with Lambda directly?
You can put AWS CloudFront in front API Gateway and Lambda so that, the traffic will be served to outside through CloudFront.
In addition by configuring AWS WAF with rate base blocking, it is possible to block high frequencies of access by attackers.
However when configuring AWS CloudFront in front of API Gateway and Lambda, you also need to restrict direct access to API Gateway (Since API Gateway will be publicly accessible by default). This can be achieved in following ways.
Enable API Keys for API Gateway and use the API Key in AWS CloudFront Headers in the Origin.
Use a Token Header and Verify it using a Custom Authorizer Lambda function.
Two options spring to mind:
place API Gateway in front of Lambda so that API requests
have to be authenticated. API Gateway also has built-in throttles and other useful features.
invoke the Lambda directly, which will require the client
invoking the Lambda to have the relevant IAM credentials.

WSO2 API Manager v1.8.0 - Clustering

I have a question on WSO2 API Manager Clustering. I have gone through the deployment documentation in detail and understand the distributed deployment concept where in one can seggregate the publisher, store, key manager and gateway. But as per my asessment, that makes the deployment architecture pretty complex to maintain. So I would like to have a simpler deployment.
What I have tested is to simply have two different instances of the WSO2 API Manager to run in two different boxes pointing to the same underlying data sources in MySQL. What I have seen is that, the API calls work perfectly and the tokens obtained from one WSO2 instance would work for API invocation on the other API Manager instance. The only issue with this model is that we need to deploy the APIs from individual publisher components for as many WSO2 API Manager instances that are running. I am fine to do that since the publishing will be done by one single small team. We will have a hardware load balancer in front having the API endpoint URLs and token endpoint URLs for both the API managers and the harware LB will do the load balancing.
So my question is - are there any problems in following this simple approach from the RUNTIME perspective? Does the clustering add any benefit from RUNTIME perspective for WSO2 API Manager?
Thank you.
Your approach has following drawbacks (there can be more which I do not know);
It is not scalable. Meaning - you can't independently scale (adding more instances of) store or publisher or gateway or key manager.
Distributed throttling won't work. It will lead to throttling inconsistencies since the throttling replication won't happen if you don't enable clustering. Lets say you define 'Gold' tier for an API. Doesn't matter how many gateway instances you are using, a user should be restricted to access no more than 20req/min to this API. This should have been implemented based on a distributed counter (not sure the exact implementation details). So if you don't enable clustering, one gateway node doesn't know the number of requests served by other gateway nodes. So each gateway node will have their own throttle counter. Meaning - a user might be able to access your API more than 20req/min. So this is one of the throttling inconsistencies. Further, lets say one gateway node is throttled out a user but the other gateway node is not. Now, if your LB routes the request to 1st gateway node, user will not be able to access the API. If your LB routes the request to 2nd gateway node, user will be able to access the API. This is another instance of throttling inconsistency. To overcome all these issues, you just need to replicate the throttling across all the gateway nodes by enabling clustering.
Distributed caching won't work. For example, API Key validation information are cached. If you revoke a token in one API Manager node, cache will be cleared in that node. So a user can't use revoked token via that API Manager node, BUT he is able to use the token via the other API Manager node until the cache is invalidated (I guess 15 min by default). This is just one instance where things can go wrong if you don't cluster your API Manager instances. To solve these issues, you just need to enable clustering, then the cache will be in sync across the cluster. Read this doc for more details on various caching available in WSO2 API Manager.
You will be having several issues if you don't have above features. WSO2 highly recommends distributed deployment in production.