# Configuring a Bucket Policy

A bucket policy defines the access control policy of resources (buckets and objects) in OBS.

#### Procedure

1. Log in to OBS Browser.
2. Click the blank area in the row of the bucket for which you want to configure a bucket policy and choose More > Configure Bucket Policy.
3. In the Configure Bucket Policy dialog box, input required parameters.

   The size of a bucket policy cannot exceed 20 KB.

   Table 1 describes the parameters of bucket policies. All fields except the Effect field are optional.

   Table 1 Parameters in bucket policies
   Parameter | Description | Mandatory or Not
   --- | --- | ---
   Version | The value can be 2008-10-17 or 2012-10-17. | Optional
   Id | The ID of the bucket policy. The value must be unique. | Optional

   Statement

   The description of the bucket policy. The statement defines complete permission control. Each bucket policy can have multiple statements, and each statement contains the following parameters:
   - Sid
   - Effect
   - Principal
   - NotPrincipal
   - Action
   - NotAction
   - Resource
   - NotResource
   - Condition

   Mandatory

   Effect | Effect of the bucket policy. The statement can be set to accept or reject requests. Possible values are Allow and Deny | Mandatory
   Sid | The statement ID. | Optional
   Principal/NotPrincipal | Users on whom the bucket policy statement takes effect Either Principal or NotPrincipal must be selected to specify the user on whom the bucket policy statement takes effect or does not take effect. | Mandatory
   Action/NotAction | OBS operations on which the bucket policy statement takes effect Either Action or NotAction must be selected to specify whether the bucket policy statement takes effect on the OBS operation. | Mandatory
   Resource/NotResource | Objects on which the bucket policy statement takes effect Either Resource or NotResource must be selected to specify whether the bucket policy statement takes effect on the OBS resources. | Mandatory
   Condition | The conditions under which the bucket policy takes effect | Optional

   Example: Uploading objects to bucket bucket-example is not allowed.

       {
           "Version":"2008-10-17",
           "Id":"Policy1527928945090",
           "Statement":[
               {
                   "Sid":"Stmt1527929149040",
                   "Effect":"Deny",
                   "Principal":
                   {
                       "AWS":[
                           "*"
                       ]
                   },
                   "Action":[
                       "s3:Put*"
                   ],
                   "Resource":[
                       "arn:aws:s3:::bucket-example/*"
                   ]
               }
           ]
       }

4. Click Save.
5. In the displayed dialog box, click Close to close the dialog box.

Parent topic: Permission Control