Is there an S3 policy for limiting access to only see/access one bucket?

Question

I have a simple bucket that looks like images.mysite.com on my S3 and other buckets containing backups, etc.

I want to allow a specific user to be able

Answer 1

I managed to get the following working. Meant that listing other buckets recieved Access Denied message. But was still able to see the bucket that I wanted if I connected with the bucket name set as path.

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Action": [
        "s3:GetBucketLocation",
        "s3:ListAllMyBuckets"
      ],
      "Resource": "arn:aws:s3:::test"
    },
    {
      "Effect": "Allow",
      "Action": ["s3:ListBucket"],
      "Resource": ["arn:aws:s3:::test"]
    },
    {
      "Effect": "Allow",
      "Action": [
        "s3:PutObject",
        "s3:GetObject",
        "s3:DeleteObject"
      ],
      "Resource": ["arn:aws:s3:::test/*"]
    }
  ]
}

I was using Cyberduck to test this connection.

Answer 2

I use the following stuff to hide bucket's contents from other users. This not only helps to hide other buckets (don't use ListAllMyBuckets), but also folders in the same bucket, when you make one bucket, but want to have subfolders in it assigning proper permissions to IAM User/subfolder.

The following policy is applied to IAM Group and all users are in this Group. You need to take aws:userid and make a subfolder with the same name in the bucket.

UserID can be taken: aws iam get-user --user-name "user_name_for_folder_access":

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "s3:*"
            ],
            "Resource": [
                "arn:aws:s3:::bucket_name/${aws:userid}/*"
            ]
        },
        {
            "Effect": "Allow",
            "Action": [
                "s3:ListBucket"
            ],
            "Resource": [
                "arn:aws:s3:::bucket_name"
            ]
        }
    ]
}

Answer 3

Try this policy. User cannot list any bucket, they have to use direct link to allowed bucket.

For example: s3.console.aws.amazon.com/s3/buckets/bucketname/?region=us-east-1&tab=overview

{
  "Statement": [
    {
      "Action": [
        "s3:ListBucket"
      ],
      "Effect": "Allow",
      "Resource": [
        "arn:aws:s3:::bucketname"
      ]
    },
    {
      "Action": [
        "s3:PutObject",
        "s3:GetObject"
      ],
      "Effect": "Allow",
      "Resource": [
        "arn:aws:s3:::bucketname*"
      ]
    },

  ],
  "Version": "2012-10-17"
}

Answer 4

This is detailed by Amazon on http://blogs.aws.amazon.com/security/post/Tx3VRSWZ6B3SHAV/Writing-IAM-Policies-How-to-grant-access-to-an-Amazon-S3-bucket

Answer 5

Add a Deny clause for the bucket(s) you do not want to access. Remember that they might still be listed, but you won't be able to access the contents inside them.

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": "s3:*",
            "Resource": "*"
        },
        {
            "Effect": "Deny",
            "Action": "s3:*",
            "Resource": [
                "arn:aws:s3:::bucket-name",
                "arn:aws:s3:::bucket-name/*"
            ]
        }
    ]
}

Answer 6

I just add a similar need, solved by this :

{
  "Version": "2012-10-17",
  "Statement": [
    {
        "Effect": "Allow",
        "Action": [
            "s3:Get*",
            "s3:Put*",
            "s3:DeleteObject",
            "s3:ListBucket"
        ],
        "Resource": [
            "arn:aws:s3:::my-bucket-name",
            "arn:aws:s3:::my-bucket-name/*"
        ]
    }
  ]
}