I am planning to map an Amazon S3 bucket as a basic shared folder/file server using TNT drive.
I've managed to map a drive in Windows perfectly fine I just need to lock down the shared folder permissions. I have some unix experience but I'm completely baffled by the Amazon permissions commands, if the folder path is;
'MyBucket/Shares/LON1'
& the user group is
'Design'
how can I grant the Design group the usual read/write/delete/list contents/create folder permissions for the folder 'LON1' but no higher?
Thanks very much,
Use IAM to assign permissions to buckets. Each user will have it's own Access Key ID and Secret Access Key. You can restrict access to the bucket and folders based on the policies you attach to the user or the group that the user belong to.
For example the following policy:
{
"Version": "2012-10-17",
"Statement": [
{
"Sid": "Stmt1388785271000",
"Effect": "Allow",
"Action": [
"s3:*"
],
"Resource": [
"arn:aws:s3:::bucketname/objectpath"
]
}
]
}
will allow the user or group to do all possible actions on bucketname/objectpath.
Here's a walkthrough from Amazon:
http://docs.aws.amazon.com/AmazonS3/latest/dev/walkthrough1.html
Please refer to the following policy to restrict the user to upload or list objects only to specific folders. I have created a policy that allows me to list only the objects of folder1 and folder2, and also allows to put the object to folder1 and deny uploads to other folders of the buckets. The policy does as below: 1.List all the folders of bucket 2.List objects and folders of allowed folders 3.Uploads files only to allowed folders
{
"Version": "2012-10-17",
"Statement": [{
"Sid": "AllowUserToSeeBucketListInTheConsole",
"Action": ["s3:ListAllMyBuckets", "s3:GetBucketLocation"],
"Effect": "Allow",
"Resource": ["arn:aws:s3:::"]
}, {
"Sid": "AllowListingOfFolder1And2",
"Action": ["s3:"],
"Effect": "Deny",
"Resource": ["arn:aws:s3:::bucketname"],
"Condition": {
"StringNotLike": {
"s3:prefix": ["folder1/", "folder2/"]
},
"StringLike": {
"s3:prefix": ""
}
}
}, {
"Sid": "Allowputobjecttofolder1only",
"Effect": "Deny",
"Action": "s3:PutObject",
"NotResource": "arn:aws:s3:::bucketname/folder1/"
}]
}
Related
I know how to create a user through AWS Console en IAM, but I wonder where or how should I set the permissions to that user in order that he only could:
upload/delete files to a specific folder in a specific S3 bucket
I have this bucket:
So I wonder if I have to set up the permissions in that interface, or directly in the user in IAM service
I'm creating a Group there with this policy:
but for "Write" and "Read" there are a lot of policies, which ones do I need only for write/read files in a specific bucket?
Edit: Currently I have this policy:
{
"Version": "2012-10-17",
"Statement": [
{
"Sid": "VisualEditor0",
"Effect": "Allow",
"Action": [
"s3:PutObject",
"s3:ListBucket",
"s3:DeleteObject"
],
"Resource": "arn:aws:s3:::static.XXXXXX.com/images/carousel/*",
"Condition": {
"BoolIfExists": {
"aws:MultiFactorAuthPresent": "true"
}
}
}
]
}
I wonder if that is enough to:
log in AWS Console
go to S3 buckets and delete/read objects in the folder of the bucket that I want
You can attach a role to that user that gets a custom policy (Doc).
There you can choose the service, the actions which you want to allow and also the resource which are whitelisted.
You can either use a resource based policy that is attached with S3 or an identity based policy attached to an IAM User, Group or Role.
Identity-based policies and resource-based policies
You can attach below identity policy to the user to upload/delete files to a specific folder in a specific S3 bucket.
{
"Version": "2012-10-17",
"Statement": [
{
"Sid": "VisualEditor0",
"Effect": "Allow",
"Action": [
"s3:PutObject",
"s3:DeleteObject"
],
"Resource": "arn:aws:s3:::SAMPLE-BUCKET-NAME/foldername"
}
]
}
For more details, refer Grant Access to User-Specific Folders in an Amazon S3 Bucket
I need to create an IAM policy that restricts access only to the user's folder. I followed the guidelines as specified here:
https://docs.amazonaws.cn/en_us/AmazonS3/latest/dev/walkthrough1.html
I also am using this S3 browser since I don't like my users to be using the console: https://s3browser.com/
However, when I tried navigating to the bucket root folder, it gives me an "Access Denied. Would you like to try Requester Pays access?" error.
But if I specify the prefix with the user's folder, I receive no error. Here's the IAM policy I have created:
{
"Version": "2012-10-17",
"Statement": [
{
"Sid": "AllowRequiredAmazonS3ConsolePermissions",
"Effect": "Allow",
"Action": [
"s3:ListAllMyBuckets",
"s3:GetBucketLocation"
],
"Resource": "*"
},
{
"Sid": "VisualEditor0",
"Effect": "Allow",
"Action": "s3:ListBucket",
"Resource": [
"arn:aws:s3:::bucket-name"
],
"Condition": {
"StringEquals": {
"s3:prefix": [
""
],
"s3:delimiter": [
"/"
]
}
}
}
]
}
The expected result for this IAM policy should allow the user to navigate from the root folder to his/her specific folder.
Your s3:ListBucket has a condition that it will only allow listing of objects when in certain prefix. This is the expected behavior of this policy. If you remove this condition then the person can view all objects in your whole bucket.
There is no way to let user navigate via gui since he isn't allowed to see the folders in the root.
I'm trying to define a policy for a specific user.
I have several buckets in my S3 but I want to give the user access to some of them.
I created the following policy:
{
"Version":"2012-10-17",
"Statement":[
{
"Sid":"AddPerm",
"Effect":"Allow",
"Principal": "*",
"Action":["s3:GetObject",
"s3:ListBucket",
"s3:ListAllMyBuckets",
"s3:GetBucketLocation",
"s3:PutObject"],
"Resource":["arn:aws:s3:::examplebucket"]
}
when I try to add a list of resources like this:
"Resource":["arn:aws:s3:::examplebucket1","arn:aws:s3:::examplebucket2"]
I get access denied
The only option that works for me (I get buckets lists) is:
"Resource": ["arn:aws:s3:::*"]
whats the problem?
Some Amazon S3 API calls operate at the Bucket-level, while some operate at the Object-level. Therefore, you will need a policy like:
{
"Version": "2012-10-17",
"Statement": [
{
"Effect": "Allow",
"Action": ["s3:ListBucket"],
"Resource": ["arn:aws:s3:::test"]
},
{
"Effect": "Allow",
"Action": [
"s3:PutObject",
"s3:GetObject",
"s3:DeleteObject"
],
"Resource": ["arn:aws:s3:::test/*"]
}
]
}
See: AWS Security Blog - Writing IAM Policies: How to Grant Access to an Amazon S3 Bucket
I found that its an AWS limitation.
There is no option get filtered list of buckets.
Once you give permissions to ListAllMyBuckets like this:
{
"Sid": "AllowUserToSeeBucketListInTheConsole",
"Action": ["s3:GetBucketLocation", "s3:ListAllMyBuckets"],
"Effect": "Allow",
"Resource": ["arn:aws:s3:::*"]
}
you get the list of all bucket (including buckets that you don't have permissions to it).
More info could be found here: https://aws.amazon.com/blogs/security/writing-iam-policies-grant-access-to-user-specific-folders-in-an-amazon-s3-bucket/
Few workarounds could be found here: Is there an S3 policy for limiting access to only see/access one bucket?
I have setup an unauthenticated role under Amazon Cognito Identity pool. My goal is that guest users of my mobile app would be able to upload debugging logs (small text files) to my S3 bucket so I can troubleshoot issues. I notice I would get "Access Denied" from S3 if I don't modify my S3 bucket permission. If I add allow "Everyone" to have "Upload/Delete" privilege, the file upload succeeded. My concern is someone would then be able to upload large files to my bucket and cause a security issue. What is the recommend configuration for my need above? I am a newbie to S3 and Cognito.
I am using Amazon AWS SDK for iOS but I suppose this question is platform neutral.
Edit:
My policy is as follows:
{
"Version": "2012-10-17",
"Statement": [
{
"Effect": "Allow",
"Action": "iam:GetUser",
"Resource": "*"
},
{
"Effect": "Allow",
"Action": [
"s3:ListAllMyBuckets"
],
"Resource": "*"
},
{
"Effect": "Allow",
"Action": [
"s3:CreateBucket",
"s3:DeleteBucket",
"s3:DeleteObject",
"s3:GetBucketLocation",
"s3:GetObject",
"s3:ListBucket",
"s3:PutObject"
],
"Resource": ["arn:aws:s3:::import-to-ec2-*", "arn:aws:s3:::<my bucket name>/*"]
}
]
}
You don't need to modify the S3 bucket permission, but rather the IAM role associated with your identity pool. Try the following:
Visit the IAM console.
Find the role associated with your identity pool.
Attach a policy similar to the following to your role:
{
"Version": "2012-10-17",
"Statement": [
{
"Effect": "Allow",
"Action": ["s3:PutObject"],
"Resource": ["arn:aws:s3:::MYBUCKET/*"]
}
]
}
Replace MYBUCKET with your bucket name
Access your bucket as normal from your application use the iOS SDK and Cognito
You may want to consider limiting permissions further, including ${cognito-identity.amazonaws.com:sub} to partition your users, but the above policy will get you started.
The answer above is incomplete as of 2015, you need to authorize BOTH the role AND the bucket polity in S3 to authorize that Role to write to the bucket. Use s3:PutObject in both cases. The console has wizards for both cases
As #einarc said (cannot comment yet), to make it works I had to edit role and Bucket Policy. This is good enough for testing:
Bucket Policy:
{
"Id": "Policy1500742753994",
"Version": "2012-10-17",
"Statement": [
{
"Sid": "Stmt1500742752148",
"Action": "s3:*",
"Effect": "Allow",
"Resource": "arn:aws:s3:::admin1.user1",
"Principal": "*"
}
]
}
Authenticated role's policy:
{
"Version": "2012-10-17",
"Statement": [
{
"Effect": "Allow",
"Action": [
"s3:*"
],
"Resource": [
"arn:aws:s3:::*"
]
}
]
}
I'm working to create a policy document to allow a IAM users to S3 to a specific "blog" directory where they can create/edit/delete files as well as modify file permissions inside the bucket to global read so uploaded files can be made public on a blog. Here is what I have so far, only issue is the policy is not letting the user modify permissions.
How can this policy be updated to allow the user to modify permissions to global read access?
{
"Version": "2012-10-17",
"Statement": [
{
"Effect": "Allow",
"Action": ["s3:ListAllMyBuckets"],
"Resource": "arn:aws:s3:::*"
},
{
"Effect": "Allow",
"Action": [
"s3:ListBucket",
"s3:GetBucketLocation"
],
"Resource": "arn:aws:s3:::blog"
},
{
"Effect": "Allow",
"Action": [
"s3:PutObject",
"s3:GetObject",
"s3:DeleteObject"
],
"Resource": "arn:aws:s3:::blog/*"
}
]
}
only issue is the policy is not letting the user modify permissions.
Correct. You have granted only the Put, Get and Delete Permission. In order to provide access for manipulating the Object level permission, you need to provide s3:PutObjectAcl API access.
Check s3:PutObjectAcl IAM Action documentation and S3 PUT Object acl Documentation for more details on how you can leverage this API.