I have a site which allows users to define their subdomains
xxx.mysite.com
I allow the users to upload their own avatars and logos - ideally, it should upload directly to s3.
1
I am able to generate the policy http://s3.amazonaws.com/doc/s3-example-code/post/post_sample.html here.
However, I do not know what to give
["starts-with", "$success_action_redirect", "http://xxx.mysite.com/"]
I can leave it out but I am not very comfortable allowing anyone to just upload easily. How can I add more restrictions?
I currently restrict the content-type to images
2 https and http
I know that I can force ssl on the entire site and use https://xxx.mysite.com for success_action_redirect.
Is there a regex I can use?
I'm answering my own question.
It is not possible to do a wildcard search. We can do only starts-with.
I just restricted it to https for now. The other way to do it is to have a common code for upload across subdomains and use a parent.xx browser functions. Since it is in the same domain, browser will not complain and the s3 policy will go through.
Related
The current situation is that I have a CloudFront distribution with a OAI pointing to my images bucket that are served in my app. I've managed to make the bucket policy to only allow the getObject action from the cloudfront distribution and only to be accessed from my app's domain with the Referer header.
The issue is that if someone manages to fake that referer from a script they could access the images and make a scraping bot and fetch all my data. Is there any way to prevent the access even futher to only be accessible from my own app ?
App's business is a photo news market between news agencies and photographers so my aim is to have a cheap and scalable mechanisms for those restrictions as I manage a lot of photos at once, thus a presigned request for each is load intensive and using a firewall could be very expensive.
If you don't want to go with signed urls approach, other approach you could try -
You can add a custom header along with traditional headers like referrer etc. - This will take care of 99% of the scraping, while there might be few scrapers who would replicate even this header, for them you can simply start blocking them.
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.
I'm currently looking to host an app with the Angular frontend in a AWS S3 bucket connecting to a PHP backend using the AWS Elastic Beanstalk. I've got it set up and it's working nicely.
However, using S3 to create a static website, anyone can view your code, including the various Angular JS files. This is mostly fine, but I want to create either a file or folder to keep sensitive information in that cannot be viewed by anyone, but can be included/required by all other files. Essentially I want a key that I can attach to all calls to the backend to make sure only authorised requests get through.
I've experimented with various permissions but always seems to be able to view all files, presumably because the static website hosting bucket policy ensures everything is public.
Any suggestions appreciated!
Cheers.
The whole idea of static website hosting on S3 means the content to be public, for example, you have maintenance of your app/web, so you redirect users to the S3 static page notifying there is maintenance ongoing.
I am not sure what all have you tried when you refer to "experimented with various permissions", however, have you tried to setup a bucket policy or maybe setup the bucket as a CloudFront origin and set a Signed URL. This might be a bit tricky considering you want to call these sensitive files by other files. But the way to hide those sensitive files will either be by using some sort of bucket policy or by restricting using some sort of signed URL in my opinion.
We are considering moving our file delivery to Cloudfront.
Currently, we generate "secure" URLs for our file delivery on a individual basis which look like:
http://downloads.xxxxx.com/1/2005-01-01_2006-01-01.csv?AWSAccessKeyId=012NFZM3D44FSG20CP82&Expires=1495287427&response-cache-control=No-cache&response-content-disposition=attachment%3B%20filename%3D2005-01-01_2006-01-01.csv&Signature=tWAeES3rhAlv2SQoZkqyYJEexH0%3D
Is there an easy way to apply Cloudfront to the URL above, or do we need to configure them from scratch using Signed URLs? Would the S3 authenticated URL "pass-through" using Cloudfront if I create a simple distribution there?
It is theoretically possible to configure CloudFront to pass-through an S3 signed URL, but doing so would defeat all caching, so... no, it's not a viable solution.
CloudFront uses an entirely different algorithm for signed URLs, so there's not a way to simply transform an existing S3 signed URL into a CloudFront signed URL.
Note also that you'll need to embed the existing response-* parameters in the URL before signing it. CloudFront should still pass them through so that S3 can modify its response as indicated.
Unrelated: one feature you might find interesting is that with CloudFront signed URLs, you actually have the optional ability to embed the client's IP address in the URL in such a way that the URL can only be used from a single IP address. This isn't something that can be done in a straightforward way with an S3 signed URL.
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.