Reaching GCP Cloud Run instance through VPC with "only internal range" egress - google-cloud-platform

The current setup is as follows:
I have a Cloud Run service, which acts as "back-end", which needs to reach external services but wants to be reached ONLY by the second Cloud Run instance. which acts as a "front-end", which needs to reach auth0 and the "back-end" and be reached by any client with a browser.
I recognize that the setup is not optimal, but I've inherited as is and we cannot migrate to another solution (maybe k8n). I'm trying to make this work with the least amount of impact on the infrastructure and, ideally, without having to touch the services themselves.
What I've tried is to restrict the ingress of the back-end service to INTERNAL and place two serverless VPC connectors (one per service), so that the front-end service would be able to reach the back-end but no one else could.
But I've encountered a huge issue: if I set the egress of the front-end all on the VPC it works, but now the front-end cannot reach auth0 and therefore the users cannot authenticate. If I place the egress as "mixed" (only internal ip ranges go through the VPC) the Google Run URL (*.run.app) is resolved not through the VPC and therefore it returns a big bad 403.
What I tried so far:
Placing a load balancer in front of the back-end service. But the serverless NEG only supports the global http load balancer and I'd need an internal one if I wanted an internal ip to resolve against
Trying to see if the VPC accessor itself MAYBE provided an internal (static) ip, but it doesn't seem so
Someone in another question suggested a "MIG as a proxy" but I haven't managed to figure that out (Can I run Cloud Run applications on a private IP (inside dedicated VPC network)?)
Fooled around with the Gateway API, but it seems that I'd have to provide a openAPI specification for the back-end, and I'm still under the delusion that this might be resolved with a cheaper (in terms of effort) approach.
So, I get that the Cloud Run instance cannot possibly have an internal IP by itself, but is there any kind of GCP product that can act as a proxy? Can someone elaborate on the "MIG as a proxy" approach (Managed Instance Group? Of what, though?), which might be the solution I'm looking for? (Sadly, I do not have the reputation needed to comment on that question or I would have).
Any kind of pointer is, as always, deeply appreciated.

You are designing this wrong. Use Cloud Run's identity-based access control instead of trying to route traffic. Google IAP (Identity Aware Proxy) will block all traffic that is not authorized.
Authenticating service-to-service

Related

Restrict access to some endpoints on Google Cloud

I have a k8s cluster that runs my app (gce as an ingress) and I want to restrict access to some endpoints "/test/*" but all other endpoints should be publically available. I don't want to restrict for specific IP's to have some flexibility and ability to access restricted endpoints from any device like phones.
I considered IAP but it restricts access to the full service when I need it only for some endpoints. Hence extra.
I have thought about VPN. But I don't understand how to set this up, or would it even resolve my issues.
I have heard about proxy but seems to me it can't fulfill my requirements (?)
I can't tell that solution should be super extensible or generic because only a few people will use this feature.
I want the solution to be light, flexible, simple, and fulfill my needs at the same time. So if you say that there are solutions but it's complex I would consider restricting access by the IP, but I worry about how the restricted IP's approach is viable in the real life. In a sense would it be too cumbersome to add the IP of my phone every time I change my location and so on?
You can use API Gateway for that. It approximatively meets your needs, it's not so flexible and simple.
But it's fully managed and can scale with your traffic.
For a more convenient solution, you have to use software proxy (or API Gateway), or go to the Bank and use Apigee
I set up OpenVPN.
It was not a tedious process because of the various small obstacles but I encourage you to do the same.
Get a host (machine, cluster, or whatever) with the static IP
Setup an OpenVPN instance. I do docker https://hub.docker.com/r/kylemanna/openvpn/ (follow instructions but update a host -u YOUR_IP)
Ensure that VPN setup works from your local machine
To the routes you need limit IP access to the VPN one. Nginx example
allow x.x.x.x;
deny all;
Make sure that nginx treats IP right. I had an issue that the nginx was having Load Balancer IP as client IP's, so I have to put some as trusted. http://nginx.org/en/docs/http/ngx_http_realip_module.html
Test the setup

AWS HTTP API Gateway connected to ALB returns 503

My current solution:
My application consists of two separate services/containers deployed to ECS. These services are inside Virtual Private Cloud (VPC) and to expose the application I created EC2 Application Load Balancer, which works flawlessly, I can access the application through Load Balancer URL easily.
What I'm trying to achieve:
Currently I'm trying to create an API Gateway linked to the load balancer mentioned above, to access the application by API Gateway instead of Load Balancer.
What I did to achieve this
I found an AWS tutorial which basically does what I'm trying to do, so I went step by step with this tutorial
Created Http API Gateway
Created VPC-LINK (connected to all possibles subnets and all possible security groups just in case)
Created single route ANY /{proxy+} to catch basically everything
Created integration to that route (where I selected mentioned above load balancer as a target service).
Everything is step by step, the same as in the tutorial, but unfortunately last step where I should see my webpage I see ERROR: 503 {"message":"Service Unavailable"}
What I did additionally to solve the issue:
Added Api Gateway logs, but I'm not receiving anything interesting there, just raw data like below:
{
"requestId": "PgELwjAyjoEEPgQ=",
"ip": "185.244.96.51",
"requestTime": "24/Mar/2022:18:09:40 +0000",
"httpMethod": "GET",
"routeKey": "ANY /{proxy+}",
"status": "503",
"protocol": "HTTP/1.1",
"responseLength": "33"
}
played with different load balancer listeners (443 or 80).
played with different security groups (tried with same security groups as ALB, or with all possible security groups)
The question is, what I'm missing here?
I guess the problem lies somewhere in the connection between VPC link and load balancer, but to be honest I don't know how to check and verify it. I clicked everything step by step, in many places there was single choice option, so I'm really confused where I could have made a mistake. Here is an illustrative photo of the infrastructure and my guess where the problem could be (but it's still a guess.
The only thing I can think of is, why? Like seriously, APIGW doesn't provide any additional value over the ALB. If you are already using an ALB, the easiest, cheapest, and best thing to do, is point your route53 DNS at the ALB and be done.
In any case VPC-link will never work, APIGW doesn't work with internal VPC, and VPC-link requires the client to be in the same VPC as the service. Since VPC-link is inside the VPC and the HTTP API is outside of course this would cause a problem, and specifically "I can't find that dependency" where 503 is the expected status code.
If some ridiculous reason you still wanted to use APIGW with a public ALB, you can point the APIGW directly at the ALB DNS, and be done. But again, this offers negative value AND costs additional money + performance for an all around negative impact on your users, developers, and your corporate wallet.
If for some reason after all that, here is the AWS Documentation on VPC-Link. In reality the problem with the setup is likely a further configuration issue. You can validate this by checking the ALB flow logs.
One reason to want to do this approach is that the API Gw is being used with say Cognito to provide the access security to the backend API in the VPC rather than say an x-api-key header which is very insecure. In this way API Gw can provide user group level security of all the APIs exported by the backend service. It can also be used to deny access to certain apis through route configuration.

Private service to service communication for Google Cloud Run

I'd like to have my Google Cloud Run services privately communicate with one another over non-HTTP and/or without having to add bearer authentication in my code.
I'm aware of this documentation from Google which describes how you can do authenticated access between services, although it's obviously only for HTTP.
I think I have a general idea of what's necessary:
Create a custom VPC for my project
Enable the Serverless VPC Connector
What I'm not totally clear on is:
Is any of this necessary? Can Cloud Run services within the same project already see each other?
How do services address one another after this?
Do I gain the ability to use simpler by-convention DNS names? For example, could I have each service in Cloud Run manifest on my VPC as a single first level DNS name like apione and apitwo rather than a larger DNS name that I'd then have to hint in through my deployments?
If not, is there any kind of mechanism for services to discover names?
If I put my managed Cloud SQL postgres database on this network, can I control its DNS name?
Finally, are there any other gotchas I might want to be aware of? You can assume my use case is very simple, two or more long lived services on Cloud Run, doing non-HTTP TCP/UDP communications.
I also found a potentially related Google Cloud Run feature request that is worth upvoting if this isn't currently possible.
Cloud Run services are only reachable through HTTP request. you can't use other network protocol (SSH to log into instances for example, or TCP/UDP communication).
However, Cloud Run can initiate these kind of connection to external services (for instance Compute Engine instances deployed in your VPC, thanks to the serverless VPC Connector).
the serverless VPC connector allow you to make a bridge between the Google Cloud managed environment (where live the Cloud Run (and Cloud Functions/App Engine) instances) and the VPC of your project where you have your own instances (Compute Engine, GKE node pools,...)
Thus you can have a Cloud Run service that reach a Kubernetes pods on GKE through a TCP connection, if it's your requirement.
About service discovery, it's not yet the case but Google work actively on that and Ahmet (Google Cloud Dev Advocate on Cloud Run) has released recently a tool for that. But nothing really build in.

AWS 3-Tier Architecture Issue

Need some serious help here, thanks a lot in advance !
I need to deploy a scalable 3 tier web application on AWS and I am having some doubts/trouble understanding the best practice to design the architecture.
NOTE: As per my understanding, all the backend requests are requested through the browser, after the Frontend server serves html/css/js to the user.
Let me show you what I have come up with till now :
Assuming the above 'note':
Cons (as per my understanding):
All the backend routes will be exposed to the outside world.
Even though backend servers are in private subnet, now that they're being accessed via external load balancer, the endpoints API could be accessed from the users.
How will we route a request from a Load balancer to another Load balancer. Because what I have seen is that you could only route a request to an EC2 instance added in the target group.
To overcome the cons as I think in the above approach, I came up with this architecture instead:
Pros (as per my understanding):
The backend routes are safe (in a way) because we have a way of internally connecting from the frontend to the backend servers(if required).
Cons:
If the request is made from the browser, the endpoints are again exposed.
Solution that I found online:
REAL BIG DOUBT IN THIS LAST ONE
This breaks all the logic of my understanding that : All the requests are made by the browser from the user to the backend because in this the requests to the backend are being routed FROM the frontend servers.
QUESTIONS
What if the backend request (say login) is made by the user from the browser?
How will this work out in such case?
seems like you have done some good work here.
Let me start by making things easy for you:
Users only interact with the Load Balancer: If you want to keep it simple and not break off your frontend asset serving to an external service like CloudFront, which you should if you are starting out, you will be hosting the application only via EC2 instances (application origin, or simply orgin). Your requests would look something like this:
Users <--> ALB <--> EC2
Notice how users never interact with EC2 instances directly, its always via Application Load Balancer (ALB).
If I can oversimply thing, this is how HTTP operates, a request is made to a resource at an IP and the response is sent back from the same resource or IP. So as in your diagram, a request will not be responded back by EC2 but rather be relayed via the ALB.
You don't need NAT gateway: NAT gateway are there to make it possible for resources in provate subnet access the internet. In this case, unless you want your application to access the internet, you don't need NAT gateway. Many large scale applications are actually locked down in part by not keeping this resource at all.
You are still protecting the origin: Given that only the ALB can be accessed over the internet and everything else internal you can structure things here in any way that you want to. you could have few internal microservices that can be used internally without ever being exposed to end users. Note that here request never leaves the VPN.
You can read more about this and build a sample application via the official docs here or access AWS tutorials here.
To me, #3 is the correct solution because it does not expose /api to end users (since you mention "I DO NOT want the users to directly access the /api"). In #1, I don't think you could limit access to /api to only the front-end servers, since security groups work on the whole load balancer, not per-target.
Also, being an Internet-facing load balancer, any requests from the front-end servers to the load balancer in #1 will be referencing the load balancer via public IP addresses. This will cause a 1c/GB charge to go "out of" the VPC and then back in again.
Only #3 correctly refers to back-end resources via private IP addresses. The internal load balancer will be referenced via private IP addresses.

Setting up a loadbalancer behind a proxy server on Google Cloud Compute engine

I am looking to build a scalable REST webservice on the Google Cloud Compute Engine but have a couple of requirements that I am not sure how best to implement.
Structure so far:
2 Instances running a REST webservice connected to a MySQL Cloud database.
(number of instances to scale up in the future)
Load balancer to split request between the two or more Instances.
this part is fine.
What I need next is that the traffic (POST requests from instances to an external webservice) must come from a single IP address. I assume these requests can not route back through the public IP of the load balancer?
I get the impression the solution to this is to route all requests from instances though a 3rd instance running squid. Is this the best way to do this? (side question)
Now to my main question:
I have been reading about ApiAxle which sounds like a nice proxy for Web Services, giving some good access control, throttling and reporting capabilities.
Can I have an instance running ApiAxle followed by a google cloud Load Balancer which shares the request from the proxy to the backend instances that do the leg work and feed the response back through the ApiAxle proxy, thus having everything though a single IP visible to clients using the API? (letting me add new instances to the pool to add capacity.)
and Would the proxy be much of a bottle neck?
Thanks in advance.
/Dave
(new to this, so sorry if its a stupid question because I cant find anything like this on the web)
Sounds like you need to NAT on your outbound traffic so it appears to come from one IP address. You need to do that via a third instance since Google LB stack doesn't provide this. GCLB works only with inbound connections on the load-balanced IP.
You can setup source-NAT using advanced routing, or you can use a proxy as you suggested.