CloudFront - Editing Origin - Restrict Bucket Access - amazon-s3

I have a situation which I am unable to understand easily why and I am not able to find any documentation either.
I have done the following:
Created a S3 bucket
Given public access to it
Enabled it for static website hosting
Created a CloudFront distribution to it
Enabled HTTPS at cloudfront
Now I am trying to restrict the access of S3 bucket only to CloudFront.
I tried the steps presented at
https://docs.aws.amazon.com/AmazonCloudFront/latest/DeveloperGuide/private-content-restricting-access-to-s3.html
Unfortunately, when I tried to edit the origin I don't see all the options in the UI especially Restrict Bucket Access is missing.
I only see options to edit Origin Domain Name, Origin Path, Origin Id (grayedout), Origin Custom Headers - No option to enter OAI or setting Restrict Bucket Access etc.
Is it because of enabling HTTPS?
S3 masters, please help!

Origin access identities are only applicable when using the S3 REST endpoint (e.g. example-bucket.s3.amazonaws.com) for the bucket -- not when you are using the website hosting endpoint (e.g. example-bucket.s3-website.us-east-2.amazonaws.com), because website hosting endpoints do not support authenticated requests -- they are only for public content... but OAI is an authentication mechanism.
When using the website endpoint, CloudFront does not treat the origin as an S3 Origin -- it is treated as a Custom Origin, and these options are not available, because if they were available, they wouldn't work anyway (for the reason mentioned above).

For those who have since changed some S3 settings to not be public and intend it to be only retrievable via Cloudfront, it is now there but hidden. You just have to cut copy the value from Origin Domain Name in origin tab and then re-paste it in again (if its the name bucket) and the UI will now render with the Restrict Access input options.

Related

CloudFront or S3 ACL: This XML file does not appear to have... AccessDenied / Failed to contact the origin

I'm using custom domain and CloudFront for S3 static hosting site to serve https.
It's working fine when I open the pages through the app's internal buttons or link,
but if I input direct URL in the address bar, or click the browser refresh button, it shows
This XML file does not appear to have any style information associated with it. The document tree is shown below.... Access Denied error screen.
I searched related answers and tried to /index.html in the CloudFront general setting as Default Root Object but it didn't work. (Before this try, it was index.html)
When I updated it as /index.html, even the domain itself didn't work.
I have another S3 static hosting site without CloudFront and certificate just for testing.
This site is working fine even I input direct url or click the refresh button.
Above two S3 bucket have same settings (root object is index.html and error document is also index.html)
After this, I changed CloudFront Origin Domain Name from REST endpoint to website endpoint referred to this docs (https://aws.amazon.com/premiumsupport/knowledge-center/s3-website-cloudfront-error-403/)
But now getting this error when I refresh the screen.
All the object in S3 is owned to bucket owner and has public access.
This app is made by React and using react-router-dom.
Could you give me any hint or advice?
Thanks.
Solved...
My S3 bucket region requires . instead of - when I use website endpoint for cloudfront.
And FYI..
In my case, there are some little difference with the document and some tutorial. My CloudFront distribution doesn't need to use default root object, and individual objects in S3 has no public access but the bucket has it.
There are some specific endpoints to be used for website hosting buckets, which are listed in the Amazon Simple Storage Service endpoints and quotas document. For example, when hosting in eu-west-1, cloudfront will prepopulate the dropdown with example.s3.eu-west-1.amazonaws.com, but if you look into the bucket settings, Static website hosting section, it will show you the correct url example.s3-website-eu-west-1.amazonaws.com
Carefully read the table! The url scheme is not fully consistent, eg. s3-website.us-east-2.amazonaws.com but s3-website-us-east-1.amazonaws.com - just to make your day a bit more joyful.
So I had the exact same issue and was able to resolve it after taking the s3 bucket endpoint located in the properties of the s3 bucket and then pasting it into the cloudfront origins section into the origin domain. I removed the beginning of the endpoint for example: "http://website.com.s3-website.us-east-2.amazonaws.com" you would just remove the "http://" and then post the rest into the cloudfront origin domain and click save. That should solve the problem!
I tried all kinds of different options such as making sure every object was public as well in the s3 bucket. Make sure your s3 bucket is also publicly available.
Certain regions do have different endpoints for your s3 buckets. Here is a link that shows more of that: https://aws.amazon.com/premiumsupport/knowledge-center/s3-rest-api-cloudfront-error-403/

How to use Akamai infront of S3 buckets?

I have a static website that is currently hosted in apache servers. I have an akamai server which routes requests to my site to those servers. I want to move my static websites to Amazon S3, to get away from having to host those static files in my servers.
I created a S3 bucket in amazon, gave it appropriate policies. I also set up my bucket for static website hosting. It told me that I can access the site at
http://my-site.s3-website-us-east-1.amazonaws.com
I modified my akamai properties to point to this url as my origin server. When I goto my website, I get Http 504 errors.
What am i missing here?
Thanks
K
S3 buckets don't support HTTPS?
Buckets support HTTPS, but not directly in conjunction with the static web site hosting feature.
See Website Endpoints in the S3 Developer Guide for discussion of the feature set differences between the REST endpoints and the web site hosting endpoints.
Note that if you try to directly connect to your web site hosting endpoint with your browser, you will get a timeout error.
The REST endpoint https://your-bucket.s3.amazonaws.com will work for providing HTTPS between bucket and CDN, as long as there are no dots in the name of your bucket
Or if you need the web site hosting features (index documents and redirects), you can place CloudFront between Akamai and S3, encrypting the traffic inside CloudFront as it left the AWS network on its way to Akamai (it would still be in the clear from S3 to CloudFront, but this is internal traffic on the AWS network). CloudFront automatically provides HTTPS support on the dddexample.cloudfront.net hostname it assigns to each distribution.
I admit, it sounds a bit silly, initially, to put CloudFront behind another CDN but it's really pretty sensible -- CloudFront was designed in part to augment the capabilities of S3. CloudFront also provides Lambda#Edge, which allows injection of logic at 4 trigger points in the request processing cycle (before and after the CloudFront cache, during the request and during the response) where you can modify request and response headers, generate dynamic responses, and make external network requests if needed to implement processing logic.
I faced this problem currently and as mentioned by Michael - sqlbot, putting the CloudFront between Akamai and S3 Bucket could be a workaround, but doing that you're using a CDN behind another CDN. I strongly recommend you to configure the redirects and also customize the response when origin error directly in Akamai (using REST API endpoint in your bucket). You'll need to create three rules, but first, go to CDN > Properties and select your property, Edit New Version based on the last one and click on Add Rule in Property Configuration Settings section. The first rule will be responsible for redirect empty paths to index.html, create it just like the image below:
builtin.AK_PATH is an Akamai's variable. The next step is responsible for redirect paths different from the static ones (html, ico, json, js, css, jpg, png, gif, etc) to \index.html:
The last step is responsible for customize an error response when origin throws an HTTP error code (just like the CloudFront Error Pages). When the origin returns 404 or 403 HTTP status code, the Akamai will call the Failover Hostname Edge Server (which is inside the Akamai network) with the /index.html path. This setup will be triggered when refreshing pages in the browser and when the application has redirection links (which opens new tabs for example). In the Property Hostnames section, add a new hostname that will work as the Failover Hostname Edge Server, the name should has less than 16 characters, then, add the -a.akamaihd.net suffix to it (that's the Akamai pattern). For example: failover-a.akamaihd.net:
Finally, create a new empty rule just like the image below (type the hostname that you just created in the Alternate Hostname in This Property section):
Since you are already using Akamai as a CDN, you could simply use their NetStorage product line to achieve this in a simplified manner.
All you would need to do is to move the content from s3 to Akamai and it would take care of the rest(hosting, distribution, scaling, security, redundancy).
The origin settings on Luna control panel could simply point to the Netstorage FTP location. This will also remove the network latency otherwise present when accessing the S3 bucket from the Akamai Network.

Allow access to private S3 bucket only when a particular header is present in request

I have a private bucket in S3 and would like to only allow access only to requests that include a particular (secret) header, sent from a CDN (not CloudFront, as that would of course be simple to allow using its own id).
So that means writing a bucket policy to allow just those secret-header requests.
I've been doing some research (http://docs.aws.amazon.com/AmazonS3/latest/dev/example-bucket-policies.html) and I can see that you can test other attributes of the request like aws:Referer to do a comparison on the referer, and aws:SourceIp to do a comparison on the source IP - but how would I go about doing a comparison on a custom header e.g. "X-my-secret-header"?
Do bucket policies support testing header values? If so, how?
AWS recommends using the "Referer" header to store a token and then use an AWS Bucket Policy that restricts requests to aws:Referer headers that match the token. Note that the token is not the actual referer URL, it's just whatever secret you want to use.
You will need to make sure that the requests from your CDN to S3 are over HTTPS so that secret token is encrypted.
This is described in the AWS article How do I use CloudFront to serve a static website hosted on Amazon S3? under the section "Using a website endpoint as the origin, with access restricted by a Referer header" Assuming you can set the "Referer" header from your CDN to the origin, the same concepts should apply.

How can I hide a custom origin server from the public when using AWS CloudFront?

I am not sure if this exactly qualifies for StackOverflow, but since I need to do this programatically, and I figure lots of people on SO use CloudFront, I think it does... so here goes:
I want to hide public access to my custom origin server.
CloudFront pulls from the custom origin, however I cannot find documentation or any sort of example on preventing direct requests from users to my origin when proxied behind CloudFront unless my origin is S3... which isn't the case with a custom origin.
What technique can I use to identify/authenticate that a request is being proxied through CloudFront instead of being directly requested by the client?
The CloudFront documentation only covers this case when used with an S3 origin. The AWS forum post that lists CloudFront's IP addresses has a disclaimer that the list is not guaranteed to be current and should not be relied upon. See https://forums.aws.amazon.com/ann.jspa?annID=910
I assume that anyone using CloudFront has some sort of way to hide their custom origin from direct requests / crawlers. I would appreciate any sort of tip to get me started. Thanks.
I would suggest using something similar to facebook's robots.txt in order to prevent all crawlers from accessing all sensitive content in your website.
https://www.facebook.com/robots.txt (you may have to tweak it a bit)
After that, just point your app.. (eg. Rails) to be the custom origin server.
Now rewrite all the urls on your site to become absolute urls like :
https://d2d3cu3tt4cei5.cloudfront.net/hello.html
Basically all urls should point to your cloudfront distribution. Now if someone requests a file from https://d2d3cu3tt4cei5.cloudfront.net/hello.html and it does not have hello.html.. it can fetch it from your server (over an encrypted channel like https) and then serve it to the user.
so even if the user does a view source, they do not know your origin server... only know your cloudfront distribution.
more details on setting this up here:
http://blog.codeship.io/2012/05/18/Assets-Sprites-CDN.html
Create a custom CNAME that only CloudFront uses. On your own servers, block any request for static assets not coming from that CNAME.
For instance, if your site is http://abc.mydomain.net then set up a CNAME for http://xyz.mydomain.net that points to the exact same place and put that new domain in CloudFront as the origin pull server. Then, on requests, you can tell if it's from CloudFront or not and do whatever you want.
Downside is that this is security through obscurity. The client never sees the requests for http://xyzy.mydomain.net but that doesn't mean they won't have some way of figuring it out.
[I know this thread is old, but I'm answering it for people like me who see it months later.]
From what I've read and seen, CloudFront does not consistently identify itself in requests. But you can get around this problem by overriding robots.txt at the CloudFront distribution.
1) Create a new S3 bucket that only contains one file: robots.txt. That will be the robots.txt for your CloudFront domain.
2) Go to your distribution settings in the AWS Console and click Create Origin. Add the bucket.
3) Go to Behaviors and click Create Behavior:
Path Pattern: robots.txt
Origin: (your new bucket)
4) Set the robots.txt behavior at a higher precedence (lower number).
5) Go to invalidations and invalidate /robots.txt.
Now abc123.cloudfront.net/robots.txt will be served from the bucket and everything else will be served from your domain. You can choose to allow/disallow crawling at either level independently.
Another domain/subdomain will also work in place of a bucket, but why go to the trouble.

Create my own error page for Amazon S3

I was wondering if it's possible to create my own error pages for my S3 buckets. I've got CloudFront enabled and I am using my own CNAME to assign the S3 to a subdomain for my website. This helps me create tidy links that reference my domain name.
When someone tries to access a file that has perhaps been deleted or the link isn't quite correct, they get the XML S3 error page which is ugly and not very helpful to the user.
Is there a way to override these error pages so I can display a helpful HTML page instead?
If you configure your bucket as a 'website', you can create custom error pages.
For more details see the Amazon announcement of this feature and the AWS developer guide.
There are however some caveats with this approach, a major one being that your objects need to be publicly available.
It also works with Cloudfront, but the same public access limitations apply. See https://forums.aws.amazon.com/ann.jspa?annID=921.
If you want, you can try these out
right away by configuring your Amazon
S3 bucket as a website and making the
new Amazon S3 website endpoint a
custom origin for your CloudFront
distribution. A few notes when you do
this. First, you must set your custom
origin protocol policy to “http-only.”
Second, you’ll need to use a tool that
supports CloudFront’s custom origin
feature – the AWS Management Console
does not at this point offer this
feature. Finally, note that when you
use Amazon S3’s static website
feature, all the content in your S3
bucket must be publicly accessible, so
you cannot use CloudFront’s private
content feature with that bucket. If
you would like to use private content
with S3, you need to use the S3 REST
endpoint (e.g., s3.amazonaws.com).