I've configured an S3 bucket with CloudFront and using alternate domain name provided by CludFront (I setup the domain alias images.mydomain.com at my DNS zone file).
At my DNS host the CNAME I'm pointing to xyz.cloudfront.net. Both my s3 bucket name and CNAME domain alias are images.mydomain.com.
I want world to access my images at images.mydomain.com/image.jpg and this is working perfectly.
The problem is the same resource is directly accessible by the world via below two URLs too and I don't want this to happen. I want only images.mydomain.com/image.jpg to work for world and not the below two.
images.mydomain.com.s3.amazonaws.com/image.jpg
s3.amazonaws.com/images.mydomain.com/image.jpg
How do I achieve this? please help.
http://docs.aws.amazon.com/AmazonCloudFront/latest/DeveloperGuide/private-content-restricting-access-to-s3.html
You restrict access to Amazon S3 content by creating an origin access
identity, which is a special CloudFront user. You change Amazon S3
permissions to give the origin access identity permission to access
your objects, and to remove permissions from everyone else. When your
users access your Amazon S3 objects using CloudFront URLs, the
CloudFront origin access identity gets the objects on your users'
behalf. If your users try to access objects using Amazon S3 URLs,
they're denied access. The origin access identity has permission to
access objects in your Amazon S3 bucket, but users don't.
Related
I have provided AmazonS3FullAccess policy for both the IAM user and group. Also the buket that I am trying to access says "Objects can be public". I have explicitly made the folder inside the bucket public. Despite all this I am getting access denied error when I tried to access it through its url. Any idea on this?
Objects in Amazon S3 are private by default. This means that objects are not accessible by anonymous users.
You have granted permission for your IAM User to be able to access S3. Therefore, you have access to the objects but you must identify yourself to S3 so that it can verify your identity.
You should be able to access S3 content:
Via the Amazon S3 management console
Using the AWS CLI (eg aws s3 ls s3://bucketname)
Via authenticated requests in a web browser
I suspect that you have been accessing your bucket via an unauthenticated request (eg bucketname.s3.amazonaws.com/foo.txt. Unfortunately, this does not tell Amazon S3 who you are, so it will deny the request.
To access content with this type of URL, you can generate an Amazon S3 pre-signed URLs, which appends some authentication information to the URL to prove your identity. An easy way to generate the URL is with the AWS CLI:
aws s3 presign s3://bucketname/foo.txt
It will return a URL that looks like this:
https://bucketname.s3.amazonaws.com/foo.txt?AWSAccessKeyId=AKIAxxx&Signature=xxx&Expires=1608175109
The URL will be valid for one hour by default, up to 7 days.
There are two ways I will recommend.
go to s3 dashboard, and download the object you need, one by one manually, the bucket can be kept private at the same time.
build a gateway/a small service, to handle authentication for you, set a policy and give the permission to the service container/lambda to visit the private bucket, and restrict only specific users to download the objects.
References
download from aws s3
aws policy, permission and roles
I want to protect my s3 object from Public access and the object can only be accessed from my origin. How can I do that? I tried by setting Objects Access control to Private, then Set in the buckets CORS settings, Allowed origin to my origin with the method GET but I'm getting an error while accessing the object.
How do I set the bucket to access the bucket objects only from my origin?
It sounds like you might be asking how to make an Amazon S3 bucket accessible to a specific Amazon CloudFront distribution.
From Restricting Access to Amazon S3 Content by Using an Origin Access Identity - Amazon CloudFront:
To restrict access to content that you serve from Amazon S3 buckets, follow these steps:
Create a special CloudFront user called an origin access identity (OAI) and associate it with your distribution.
Configure your S3 bucket permissions so that CloudFront can use the OAI to access the files in your bucket and serve them to your users. Make sure that users can’t use a direct URL to the S3 bucket to access a file there.
After you take these steps, users can only access your files through CloudFront, not directly from the S3 bucket.
I want to connect CDN to an AWS S3 Bucket, but the AWS Document indicates that the bucket name must be the same as the CNAME. Therefore, it is very easy to guess the real s3 bucket url by others.
For example,
- My domain: example.com
- My S3 Bucket name: image.example.com
- My CDN CNAME(image.example.com) will point to image.example.com.s3.amazonaws.com
After that, people can access the CDN URL -> http://image.example.com to obtain the resources from my S3 Bucket. However, under this restriction, people can guess my real S3 bucket url from the CNAME (CNAME + s3.amazonaws.com) easily.
So, my question is that how can I hide my real s3 bucket url? Because I don't want to expose my real S3 url to anyone for preventing any attacks.
I am not sure I understand what you are asking for or what you are trying to do [hiding your bucket does not really help anything], however I will attempt to answer your question regarding "hiding" your bucket name. Before I answer, I would like to ask these two questions:
Why do you want to hide your S3 bucket url?
What kind of attacks are you trying to prevent?
You are correct that the S3 bucket name had to be the same as your URL. This is no longer a requirement as you can mask the S3 bucket using cloudfront. CloudFront as you know is a CDN from AWS. Thus the bucket name could be anything (randomstring).
You can restrict access to the bucket, such that only CloudFront can access it. Data in the bucket is then replicated to edge locations and served from there. Even if one knows the S3 URL, it will not do anything as access to the s3 bucket is restricted, an IAM rule grants CloudFront access and no one else.
Access restriction is done via origin access and while you can manually configure this using a bucket policy, you can also set a flag in CloudFront to do this on your behalf. More information is available here.
Use the CloudFront name in Route53. Do not use CNAME, but rather use A type, and set it up as an Alias. For more information see this document.
If you are using a different DNS provider, AWS aliases will naturally not be available. I suggest moving the zone file from your other provider to AWS. If you cannot do this, then you can still use a CNAME. Again see here for more information.
I suggest using your own domain name for CloudFront and setting up HTTPS. AWS offers certificates at no additional cost for services within AWS. You can register a certificate for your domain name which is either validated by a DNS entry or an Email. To set this up please see this document.
If you want to restrict access to specific files within AWS, you can use signed URLs. More information about that is provided here.
my cloud front distribution's origin is my S3 bucket . to access a S3 bucket object we put a url in such as like "cloudfront_domainname/object_name" it should be show the object if the object is public . but in my case the cloud front URL in the URL bar redirects a S3 URL, the data retrieved from S3 not from cloud front distribution. why it cause ?
You can optionally secure the content in your Amazon S3 bucket so users can access it through CloudFront but cannot access it directly by using Amazon S3 URLs. This prevents anyone from bypassing CloudFront and using the Amazon S3 URL to get content that you want to restrict access to. This step isn't required to use signed URLs, but we recommend it.
To require that users access your content through CloudFront URLs, you perform the following tasks:
Create a special CloudFront user called an origin access identity.
Give the origin access identity permission to read the objects in your bucket.
Remove permission for anyone else to use Amazon S3 URLs to read the objects.
Please see documentation here
Say you want to host a static web site on S3 :
You create a bucket with name your-website.com and set it up for web hosting;
You add a CNAME in your domain's zone file to point to your S3 bucket.
Great. Everything works fine when you visit http://your-website.com. But you don't want the raw/"naked" endpoint to be accessible.
Is there any setting in the bucket to disable direct access to http://your-website.com.s3-website.your-region.amazonaws.com ?
The reason is that if your web site is accessible both through http://your-website.com and http://your-website.com.s3-website.your-region.amazonaws.com would hurt your SEO (duplicate content)
You mention your major concern is SEO. For that purpose, you could use a other techniques, that are probably easier to implement than the one you initially asked about.
One of the main techniques to deal with duplicate content is to use rel=canonical, which is probably fairly easy to implement. For more information, see http://googlewebmastercentral.blogspot.com.br/2013/04/5-common-mistakes-with-relcanonical.html
If you insist on the need to disable access to the bucket unless the client connects through your CNAME, your best bet is to use CloudFront. You disable the S3 website hosting option on your bucket, make your S3 bucket private (i.e., remove bucket policies or ACLs allowing public read), create a CloudFront distribution, define your bucket as the origin, configure a CNAME on your distribution, change your DNS records to point to your distribution instead of bucket, create an Origin Access Identity (OAI) on your distribution and grant access to your bucket for that OAI. Phew.
By doing all this, there's no way for a user to access the content on your S3 bucket (unless they have an AK/SK with permissions to read the bucket, and send a signed request, obviously). The only way will be through your domain.
For more detail on Origin Access Identity, see http://docs.aws.amazon.com/AmazonCloudFront/latest/DeveloperGuide/private-content-restricting-access-to-s3.html