S3 Access Features
- By default, only the account administrator and root user have access
- Permissions can be managed with IAM.
- IAM policies can be embedded directly in S3 buckets (resource-based policies)
- Connection restrictions, such as allowing only specific IP addresses, are possible.
- Authority management (access control) is also possible with ACLs.
- Account Unit
- Bucket Unit
- Object Unit
S3 bucket policies and ACLs
Control over the publication of S3 buckets is governed by the
A bucket policy is an access control set only for buckets
ACLs can be set for both buckets and objects
ACLs can be set for both buckets and objects.
Regardless of per-bucket ACL settings
ACLs per object (data)
per object (data) will be set to take precedence regardless of the per-bucket ACL setting.
In other words, in addition to setting the ACL to disallow public access on a per-bucket basis, the
Always be sure not to allow public access to uploaded objects as well.
For this reason, we have added the
S3 public access configuration function
The scope of S3's public access configuration feature is at the bucket or account level.
Public access to all objects can be blocked.
S3 maintains compliance programs such as PCI-DSS, HIPAA/HITECH, FedRAMP, EU Data Protection Directive, and FISMA to meet regulatory requirements.
S3 also supports a number of auditing functions to monitor access requests to the source.
It is also possible to deny public access to an entire S3 bucket by enabling the block.
S3 Access Control List (ACL) access control
- Block Public Access account settings (Management Console screen)
- Setting screen to prevent new uploads from being made public by default.
Amazon S3 Access Control Lists (ACLs) allow you to manage access to buckets and objects.
Each bucket and object has an ACL attached as a subresource.
This defines the AWS accounts or groups to which access is granted and the types of access.
When Amazon S3 receives a request for a resource, it checks the corresponding ACL to ensure that the requestor has the necessary permissions.
A bucket policy is a policy that sets user access rights for a bucket.
ACLs are used to control access privileges on an object-by-object basis.
Control over S3 bucket publication
Control over the publication of S3 buckets is exercised through ACLs or bucket policies.
Bucket policies are access controls set only for buckets, while ACLs can be set for both buckets and objects.
This sets the per-object ACL to take precedence regardless of the per-bucket ACL setting.
This means that in addition to setting the ACL to not allow public access on a per-bucket basis, it is necessary to always make sure that public access is not allowed for uploaded objects as well.
For this reason, the S3 public access configuration function was added.