MSP360 News
Articles, guides, whitepapers and other useful content for MSPs and IT Professionals
CloudBerry Explorer featured image

How to Give Access to an Amazon S3 Folder to a User with CloudBerry Explorer

Published: by on Post Type: Categories: AWS, CloudBerry Explorer

In this blog post, we will demonstrate how to grant a user access to a specific folder in a bucket.

Table of Contents

    First, you need to create an IAM user and assign a policy that will allow the user to access a specific bucket and folder:

    Further reading How to Create IAM Users and Assign Policies

    As an example, we will grant access for one specific user to the bucket named cloudberry.public and ”images” folder inside it.

    Allow Required Amazon S3 Permissions

    First of all you need to specify permissions that are required for access to Amazon S3 - ListAllMyBuckets and GetBucketLocation. If these two permissions are not specified, the user will face the “Access Denied” error on each attempt to access any object within the bucket.

    Policy required:

    {
    "Sid": "AllowUserToSeeBucketListInTheConsole",
    "Action": ["s3:GetBucketLocation", "s3:ListAllMyBuckets"],
    "Effect": "Allow",
    "Resource": ["arn:aws:s3:::*"]
    }

    ListAllMyBuckets grants the user with a permission to list all the buckets in the AWS account. It is required for navigating buckets via the Amazon S3 console and CloudBerry Explorer.

    GetBucketLocation grants the user with a permission to navigate within the AWS account via the Amazon S3 console and CloudBerry S3 Explorer.

    FREE WHITEPAPER
    Mastering AWS IAM for Amazon S3
    Learn how to effectively manage the security of your Amazon S3 account to protect your and your clients' data
    New call-to-action
    WP icon

    Allow Listing Objects in the Root Folder

    Our user should have access to only one folder named “Images” but all the other folders within a bucket shall be visible for them. To have an ability to navigate objects within an S3 bucket we need to specify additional permissions. These permissions allow the user to view the contents of the root of the bucket:

    {
    "Sid": " AllowRootAndHomeListingOfCompanyBucket",
    "Action": ["s3:GetBucketLocation", "s3:ListBucket"],
    "Effect": "Allow",
    "Resource": ["arn:aws:s3:::cloudberry.public"],
    "Condition":{"StringEquals":{"s3:prefix":[""],"s3:delimiter":["/"]}}
    }

    ListBucket is required to specify a list of files and folders that will be visible to the user. Without the ListBucket permission specified user will face an access denied error each time trying to view contents of the root of the bucket.

    Note: The user won't be able to view the contents of any files or folders except his own.

    The s3:prefix condition specifies files and folders that are visible for the user.

    The s3:delimiter condition specifies a slash as a delimiter of the folder. It is not necessary to specify a delimiter but it is worth specifying as it will help to create folders and subfolders within a bucket in future.

    Allow Listing Objects in Images Folder

    Now our user can view files and folders in the root of the bucket. We shall grant them with an access to all the objects in the folder and any subfolders that might be created in future. For it we have to specify the following policy:

    {
    "Sid": "AllowListingOfUserFolder",
    "Action": ["s3:GetBucketLocation", "s3:ListBucket"],
    "Effect": "Allow",
    "Resource": ["arn:aws:s3:::cloudberry.public"],
    "Condition":{"StringLike":{"s3:prefix":["images/*"]}}
    }

    Allow All Amazon S3 Actions in Images Folder

    Finally we have to specify a list of user's actions that they shall be able to take with objects within a folder. We shall allow all the actions such as read, write, and delete permissions and limit them to just one folder - “images”.

    {
    "Sid": "AllowAllS3ActionsInUserFolder",
    "Effect": "Allow",
    "Action": ["s3:*"],
    "Resource": ["arn:aws:s3:::cloudberry.public/images/*"]
    }
    Action” element with “s3:*” specified allows the user to take all the Amazon S3 actions.
    "Resource" element limits allowed actions to just one specified folder.
    The whole policy for the user shall look like this:
    {
    "Statement": [
    {
    "Sid": "AllowUserToSeeBucketListInTheConsole",
    "Effect": "Allow",
    "Action": [
    "s3:GetBucketLocation",
    "s3:ListAllMyBuckets"
    ],
    "Resource": "arn:aws:s3:::*",
    "Condition": {}
    },
    {
    "Sid": "AllowRootAndHomeListingOfCompanyBucket",
    "Effect": "Allow",
    "Action": ["s3:ListBucket", "s3:GetBucketLocation"]
    "Resource": "arn:aws:s3:::cloudberry.public",
    "Condition": {
    "StringEquals": {
    "s3:prefix": "",
    "s3:delimiter": "/"
    }
    }
    },
    {
    "Sid": "AllowListingOfUserFolder",
    "Effect": "Allow",
    "Action": ["s3:ListBucket", "s3:GetBucketLocation"]
    "Resource": "arn:aws:s3:::cloudberry.public",
    "Condition": {
    "StringLike": {
    "s3:prefix": "Images/*"
    }
    }
    },
    {
    "Sid": "AllowAllS3ActionsInUserFolder",
    "Effect": "Allow",
    "Action": "s3:*",
    "Resource": "arn:aws:s3:::cloudberry.public/Images/*",
    "Condition": {}
    }
    ]
    }

    Create an External Bucket with CloudBerry Explorer

    Now, the user should create an External Bucket. Note that the user can use CloudBerry Explorer freeware.

    S3 Policy Actions: Creating an External Bucket

    Specifying the bucket and the path:

    S3 Policy Actions: Specifying Bucket and the Path

    After that they will be able to browse the content of the bucket and perform file operations allowed in the policy.

    S3 Policy Actions: External Bucket Added

    Note: this post applies to CloudBerry Explorer 2.7.5 and later.

    CloudBerry Explorer for Amazon S3
    • S3 bucket management
    • Security management and encryption
    • File sharing
    New call-to-action
    Explorer icon
    Ratings:
    1 Star2 Stars3 Stars4 Stars5 Stars (4 votes, average: 5.00 out of 5)
    Loading...