Application Load Balancer Redirects - amazon-web-services

I have an EC2 instance which hosts a web site running in IIS. I have also set up a AWS Application Load Balancer with a HTTPS listener into which I have added my web site's SSL certificate (held in AWS Certificate Manager). The HTTPS listener redirects traffic to my target group which in turn points to my EC2 instance. The EC2 instance uses a security group to only allow traffic from the Load Balancer.
Firstly, am I correct in thinking that the Application Load Balancer decrypts the SSL traffic and as a result, this is forwarded to my target group using HTTP (in other words, my EC2 instance's security group only needs to accept HTTP traffic from the Load Balancer and I can remove my SSL certificate from IIS)?
Secondly, the main problem that I am experiencing at the moment is that the site has relative paths to some of the resources (CSS, JavaScript, etc). As a result I am getting mixed content errors in my FireFox console when I browse the site. I set up a HTTP listener in my Load Balancer to redirect traffic to HTTPS but this doesn't seem to be working for relative paths.
I don't particularly want to edit the site to change relative paths to fully qualified HTTPS URLs as it is a very complex content management system. Also, before using the Load Balancer the site was serving content perfectly (the DNS entry pointed to my EC2 instance's public IP address and there was a rewrite rule in IIS to handle non HTTPS traffic).
Any advice would be greatly appreciated.

For your first query, I think Yes. You can remove my SSL certificate from IIS and point EC2 instance's security group to accept HTTP traffic from the Load Balancer.
For your concern on relative path's problem, please go through this link: After introducing ALB, Mixed Content Error happened
I think it will be helpful.

Open your browser and click on the Network tab and check these call should be going somewhere else which is using HTTP, these are an outgoing call from your application and redirect will not fix these issue. see the screenshot
Seems like same error in your case, you serving images from some other side, not from the EC2, It's mean those request which EC2 server is supposed to answer will work fine, but those which your code try to pull JS file or other resources these are outgoing call and this is nothing to do with LB redirect rule.
Better to update your application and all the URLs to https.
When a user visits a page served over HTTPS, their connection with the
web server is encrypted with TLS and is therefore safeguarded from
most sniffers and man-in-the-middle attacks. An HTTPS page that
includes content fetched using cleartext HTTP is called a mixed
content page. Pages like this are only partially encrypted, leaving
the unencrypted content accessible to sniffers and man-in-the-middle
attackers. That leaves the pages unsafe.

Thanks for the replies. I managed to get to the bottom of the second issue. The site's web.config had a rewrite rule which was forcing URLs to lowercase (something to do with SEO). This was causing the problems when serving the CSS and JS files. I've made the necessary updates to this rule and it now appears to work (see IIS URL rewrite module url's to lowercase).
For the first issue, the SSL certificates do not need to be installed on the IIS web server - they are only required in AWS Certificate Manager and then to be assigned to the Load Balancer which in turn has 2 listeners - one to direct HTTPS traffic to my Target Group and one to redirect HTTP traffic to HTTPS.
My IIS site now only has HTTP bindings and only accepts HTTP traffic from the Load Balancer.
All seems to work!

Related

GCP load balancer does not redirect it's own ip to domain

I have setup a GCP load balancer following the steps as displayed on https://cloud.google.com/load-balancing/docs/https/ext-http-lb-tf-module-examples#with_a_backend . I have create an A record at my dns provider and I am succesfully able to reach my service through the domain name. I have also created a http to https redirecting load balancer, which only redirects when visiting the domain name.
However my problem is that I can also still directly access my load balancers ip adress over http, which in turn redirects to my backend service thus allowing insecure access to my service. I am not sure what steps there are to debug my configurations or if anyone has experienced something similar.
The simplest method is to redirect HTTP to HTTPS at your backend. That method provides you with more options and control.
Tip: if the client arrives at an IP address, you most likely want to discard that traffic. That traffic is typically hackers, trolls, etc.
You can also set up a redirect in the load balancer:
Set up an HTTP-to-HTTPS redirect for global external HTTP(S) load balancer

Setting up redirection for www website to non www

We have our website hosted up on AWS EC2 instance behind the Application Load Balancer. Our Route 53 is targetting the Application Load Balancer.
Assuming we have a domain name - company.com
we have SSL registered for this domain *.company.com. We have this certificate enabled on the Application load balancer at 443 port.
We want our website hosted at subdomain - sub.company.com
Current Scenario:
When we access the website with http://www.sub.company.com or http://sub.company.com or https://sub.company.com.
With the rewrite rule for the first two, we are able to redirect to the third endpoint mentioned.
Problem arises in this particular case where we are trying to access the website with https://www.sub.example.com, It gives us a Non Secure Warning. How can we redirect this to https://sub.example.com ?
Things I have tried:
I have tried adding Rewrite rules on the webserver of EC2 Instance.
Added routing rules at Application Load balancer to redirect it at https://sub.example.com
Both of these solutions are not able to resolve the problem, It's maybe because SSL validation is happening at the first step of connection establishment before it reaches to load balancer layer.
How can we resolve this?
When you request a wildcard certificate, the asterisk (*) must be in the leftmost position of the domain name and can protect only one subdomain level.
For example, *.example.com can protect login.example.com and test.example.com, but it cannot protect test.login.example.com. then you have to request a separate certificate for *.login.example.com

SSL cert for AWS domain?

I have a backend service i'm running in Fargate. I need this service to have an SSL cert on its load balancer so that it can talk to other HTTPS services. I've created the load balancer and it gives me an AWS domain (my-cool-app.us-east-1.elb.amazonaws.com).
Now, when I try to request a certificate through acm, it fails and says "Additional verification required". So i'm not sure if it's possible to add an SSL cert to this load balancer without registering a custom domain?
Also, this is a Django app and I haven't done anything other than keep it as runserver which I know isn't good for production but I just need to start by making it work as a dev environment. Do I need to change the way Django runs in order for SSL to work? Or is the load balancer sufficient?
To use an SSL for a domain you need to have control over that domain. For the AWS managed certificate service (ACM) you can verify through either DNS validation or email validation both of which you must essentially have domain control to validate.
As you're trying to use ACM for a AWS owned domain, someone from AWS would need to approve the SSL (which they won't).
Regarding your second point what you're describing is SSL offloading, in which the load balancer will serve HTTPS and then terminate encryption in transit. It will then forward the request to the Fargate container using the protocol and port defined in the target group.
The only thing you want to consider is how you display to the user, for example ensure that all CSS, JS ans links on your site are HTTPS. You can detect whether the incoming request used HTTPS at the load balancer by inspecting the X-Forwarded-Proto header in your application.

SSL certification not working when I don't use https before my domain name

So I was able to get SSL certificate for my website and it is on AWS but for some reason when I input www.mydomain.com or mydomain.com it still shows unsecured on the browser but when I add https to mydomain.com it shows the secure icon. Please anyone with how to solve this?
The reason is the server has no redirection policy, you need to add redirection policy to redirect site from HTTP to HTTPs.
If you are using Application load balancer you can go through below article to set up HTTP to HTTPS redirection.
redirect-http-to-https-using-alb
If you are using Nginx, then you can look into redirect-http-to-https-in-nginx
https-everywhere
SSL in web applications is only carried out when your user loads the website using HTTPS. Generally in this situation you would want to perform a redirect (a 302 is more preferable initially than a 301 as it is not permanent in the event of a rollback).
There are a number of ways you can trigger a redirection without having to make any server changes, it all depends on your infrastructure setup.
If the first point of call is CloudFront you can update your viewer protocol policy to Redirect HTTP to HTTPS. CloudFront will redirect any HTTP request before they touch the origin.
If you're using an application load balancer then you can update your listener rule for HTTP to redirect HTTP to HTTPS. As with the above requests would not be forwarded to your host.
Otherwise if you're a Classic Load Balancer, Network Load Balancer or just plain EC2 then it falls to you modifying the configuration of your hosts to do the redirect (remembering to set to a 302).
Below are links for most common web servers:
Apache
Nginx
IIS
Tomcat
Once you're happy with the redirect, feel free to set as a 301.
The above answer work but in addition, if you are using a load balancer in your AWS EC2 instance you can follow this video link to the best explanation and practice.
How to redirect HTTP traffic to HTTPS in the EC2 Elastic Load Balancer

Redirect HTTP to HTTPS on Classic Load Balancer AWS

I have a classic load balancer that reads from both port 80 (http) and 433 (https) for my elastic beanstalk application. I have correctly setup an SSL certificate and everything works properly with my custom domain.
However, when I search for my domain: mydomain.com it automatically uses http instead of https. How can I allow it to use https automatically?
Edit: I am trying to deploy a django application.
New to this so let me know if I am leaving out some information.
If you're not tied to a Classic Load Balancer, I recommend switching to an Application Load Balancer: it will give you much more control over how you route requests, and supports HTTP->HTTPS redirect out of the box (doc here although you'll probably want to read the rest of that page and work through one of the tutorials to understand the context).
If you are tied to the Classic ELB then you'll have to do the redirect in your client code. I'm not familiar with Django, but it seems straightforward. The prior answer on that question shows how to do it if you have nginx in front of Django.