Run the common bucket-policy command - Object Storage Service

Bucket policies are resource-based authorization policies. Bucket owners can use bucket policies to authorize other users to access specific resources in Object Storage Service (OSS). This topic describes how to run the bucket-policy command to add, modify, query, or delete bucket policies.

Usage notes

To add or modify bucket policies, you must have the oss:PutBucketPolicy permission. To query bucket policies, you must have the oss:GetBucketPolicy permission. To delete bucket policies, you must have the oss:DeleteBucketPolicy permission. For more information, see Attach a custom policy to a RAM user.

Sample command lines in this topic are based on the 64-bit Linux system. For other systems, replace ./ossutil64 in the commands with the corresponding binary name. For more information, see ossutil command reference.
For more information about bucket policies, see Bucket policies.

Add or modify bucket policies

Before you add or modify bucket policies, you must create a JSON file on your local computer and configure bucket policies in the JSON file. You can configure multiple bucket policies in a single JSON file. However, the total size of the bucket policies cannot exceed 16 KB.

When you add or modify bucket policies, ossutil reads bucket policies from the JSON file and adds the policies to the specified bucket. When you add bucket policies, existing bucket policies are overwritten.

Command syntax
```
./ossutil64 bucket-policy --method put oss://bucketname local_json_file
```
The following table describes the parameters in the preceding command.
Parameter
Description
bucketname
The name of the bucket for which you want to add or modify bucket policies.
local_json_file
The name of the local JSON file in which you configure bucket policies.

Examples

Create a file named local_json_file on your local computer and configure different bucket policies based on different scenarios.

The following examples show how to configure common bucket policies:

Note

The following examples show how the bucket owner whose UID is 174649585760xxxx in the Resource parameter configures bucket policies to grant different permissions to RAM users, such as the RAM user whose UID is 20214760404935xxxx in the Principal parameter and the anonymous user *.

Specify that only anonymous requests from the specified IP address are allowed to access all resources in a bucket named examplebucket:

{
    "Statement": [
        {
            "Action": [
                "oss:GetObject",
                "oss:GetObjectAcl",
                "oss:ListObjects",
                "oss:RestoreObject",
                "oss:GetVodPlaylist",
                "oss:ListObjectVersions",
                "oss:GetObjectVersion",
                "oss:GetObjectVersionAcl",
                "oss:RestoreObjectVersion"
            ],
            "Condition": {
                "IpAddress": {
                    "acs:SourceIp": [
                        "10.10.10.10"
                    ]
                }
            },
            "Effect": "Allow",
            "Principal": [
                "*"
            ],
            "Resource": [
                "acs:oss:*:174649585760****:examplebucket/*"
            ]
        },
        {
            "Action": [
                "oss:ListObjects",
                "oss:GetObject"
            ],
            "Condition": {
                "StringLike": {
                    "oss:Prefix": [
                        "*"
                    ]
                },
                "IpAddress": {
                    "acs:SourceIp": [
                        "10.10.10.10"
                    ]
                }
            },
            "Effect": "Allow",
            "Principal": [
                "*"
            ],
            "Resource": [
                "acs:oss:*:174649585760****:examplebucket"
            ]
        }
    ],
    "Version": "1"
}

Grant a RAM user read-only permissions on the hangzhou/2020 and hangzhou/2015 directories in a bucket named examplebucket:

{
    "Statement": [
        {
            "Action": [
                "oss:GetObject",
                "oss:GetObjectAcl",
                "oss:ListObjects",
                "oss:RestoreObject",
                "oss:GetVodPlaylist",
                "oss:ListObjectVersions",
                "oss:GetObjectVersion",
                "oss:GetObjectVersionAcl",
                "oss:RestoreObjectVersion"
            ],
            "Effect": "Allow",
            "Principal": [
                "20214760404935****"
            ],
            "Resource": [
                "acs:oss:*:174649585760****:examplebucket/hangzhou/2020/*",
                "acs:oss:*:174649585760****:examplebucket/hangzhou/2015/*"
            ]
        },
        {
            "Action": [
                "oss:ListObjects",
                "oss:GetObject"
            ],
            "Condition": {
                "StringLike": {
                    "oss:Prefix": [
                        "hangzhou/2020/*",
                        "hangzhou/2015/*"
                    ]
                }
            },
            "Effect": "Allow",
            "Principal": [
                "20214760404935****"
            ],
            "Resource": [
                "acs:oss:*:174649585760****:examplebucket"
            ]
        }
    ],
    "Version": "1"
}

Reject anonymous requests to all objects in the hangzhou/2021/ directory of a bucket named examplebucket:

{
    "Statement": [
        {
            "Action": [
                "oss:RestoreObject",
                "oss:ListObjects",
                "oss:AbortMultipartUpload",
                "oss:PutObjectAcl",
                "oss:GetObjectAcl",
                "oss:ListParts",
                "oss:DeleteObject",
                "oss:PutObject",
                "oss:GetObject",
                "oss:GetVodPlaylist",
                "oss:PostVodPlaylist",
                "oss:PublishRtmpStream",
                "oss:ListObjectVersions",
                "oss:GetObjectVersion",
                "oss:GetObjectVersionAcl",
                "oss:RestoreObjectVersion"
            ],
            "Effect": "Deny",
            "Principal": [
                "*"
            ],
            "Resource": [
                "acs:oss:*:174649585760****:examplebucket/hangzhou/2021/*"
            ]
        },
        {
            "Action": [
                "oss:ListObjects",
                "oss:GetObject"
            ],
            "Condition": {
                "StringLike": {
                    "oss:Prefix": [
                        "hangzhou/2021/*"
                    ]
                }
            },
            "Effect": "Deny",
            "Principal": [
                "*"
            ],
            "Resource": [
                "acs:oss:*:174649585760****:examplebucket"
            ]
        }
    ],
    "Version": "1"
}

Add a bucket policy to the examplebucket bucket.
```
./ossutil64 bucket-policy --method put oss://examplebucket local_json_file
```
If the following output is displayed, the bucket policy is added to the examplebucket bucket:
```
1.125101(s) elapsed
```

Query bucket policies

Command syntax

./ossutil64 bucket-policy --method get oss://bucketname local_json_file

Parameter	Description
bucketname	The name of the bucket whose bucket policies you want to query.
local_json_file	The local JSON file that is used to store the queried bucket policies. If this parameter is not specified, queried bucket policies are displayed without being stored in the JSON file.

Examples
Run the following command to query the bucket policies of a bucket named examplebucket:
```
./ossutil64 bucket-policy --method get oss://examplebucket local_json_file
```
If the following output is displayed, the bucket policies of examplebucket are queried and written to the local JSON file:
```
0.212407(s) elapsed
```

Delete bucket policies

If you no longer need to use bucket policies to authorize other users to access your OSS resources, delete the configured bucket policies.

Command syntax

./ossutil64 bucket-policy --method delete oss://bucketname

Examples
Run the following command to delete all bucket policies of a bucket named examplebucket:
```
./ossutil64 bucket-policy --method delete oss://examplebucket
```
If the following output is displayed, all bucket policies of examplebucket are deleted:
```
0.530750(s) elapsed
```

Common options

If you use ossutil to switch to a bucket that is located in another region, add the -e option to the command to specify the endpoint of the region in which the specified bucket is located. If you use ossutil to switch to a bucket that belongs to another Alibaba Cloud account, you can add the -i option to the command to specify the AccessKey ID of the specified account, and add the -k option to the command to specify the AccessKey secret of the specified account.

For example, you can run the following command to configure a bucket policy for a bucket named examplebucket, which is located in the China (Hangzhou) region and is owned by another Alibaba Cloud account:

./ossutil64 bucket-policy --method put oss://examplebucket local_json_file -e oss-cn-hangzhou.aliyuncs.com -i LTAI4Fw2NbDUCV8zYUzA****  -k 67DLVBkH7EamOjy2W5RVAHUY9H****

For more information about common options, see Common options.