一、MinIO Policy 结构

Policy 结构范例：

{
   "Version" : "2012-10-17",
   "Statement" : [
      {
         "Effect" : "Allow",
         "Action" : [ "s3:<ActionName>", ... ],
         "Resource" : "arn:aws:s3:::*",
         "Condition" : { ... }
      },
      {
         "Effect" : "Deny",
         "Action" : [ "s3:<ActionName>", ... ],
         "Resource" : "arn:aws:s3:::*",
         "Condition" : { ... }
      }
   ]
}

Statement.Action指定操作内容，可以是一个或者多个 supported S3 API operations.
Statement.Resource 指定存储桶或者存储桶前缀。可以使用 * and ? 通配符，详情参见 S3 Resource Spec.

The * wildcard may result in unintended application of a policy to multiple buckets or prefixes based on the pattern match. 通配符可能会导致基于模式匹配将策略意外应用于多个存储桶或前缀。比如，arn:aws:s3:::data* 将匹配 data, data_private, and data_internal存储桶。 Specifying only * as the resource key applies the policy to all buckets and prefixes on the deployment.仅指定作为资源键将策略应用于部署中的所有存储桶和前缀。
Statement.Condition 指定一个或多个条件 supported Conditions.

二、自定义 Policy

MinIO - access-management
AWS IAM - policies 参考

MinIO PBAC 设计上兼容 AWS IAM policy的语法、结构、行为。参考 IAM documentation 获取关于 IAM, IAM policies, or IAM JSON syntax的更多资料。

Deny overrides Allow
MinIO follows AWS IAM policy evaluation rules where a Deny rule overrides Allow rule on the same action/resource. For example, if a user has an explicitly assigned policy with an Allow rule for an action/resource while one of its groups has an assigned policy with a Deny rule for that action/resource, MinIO would apply only the Deny rule.
For more information on IAM policy evaluation logic, see the IAM documentation on Determining Whether a Request is Allowed or Denied Within an Account.

自定义 Write Policy 的主体结构

{
    "Version": "2012-10-17",
    "Statement": [
        
    ]
}

基础元素 Version 、Statement 。
Version 元素支持设置两个值： 2012-10-17，当前版本；2008-10-17，较老版本。
Statement 是策略的主体元素，必需元素。可以包含一个，或一组 statements。每个独立的 statement 块需要以 { } 包含，多个 statements 需要以 [ ] 包含，如："Statement": [{...},{...},{...}]

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

Action 语法参考

常见 S3 ，及支持的 MinIO S3 Policy Actions

S3 操作	说明
s3:*
s3:CreateBucket
s3:DeleteBucket
s3:ForceDeleteBucket
s3:GetBucketLocation
s3:ListAllMyBuckets
s3:DeleteObject
s3:GetObject
s3:ListBucket
s3:PutObject

"Action": "s3:*"
"Action": "s3:ListBucket"
"Action": [
   "s3:ListAllMyBuckets",
   "s3:GetBucketLocation"
]

Effect 语法参考

Effect 元素支持 Allow 和 Deny 两个值。

Resource 语法参考

arn:partition:service:region:namespace:relative-id

标识符	描述
`Partition`	`aws` 是通用 partition name。对于AWS，如果资源位于 China (Beijing) Region，那么 partition name 就是 `aws-cn`。
`Service`	默认 `s3`。
`Relative ID`	`存储桶名` 或 `存储桶名/对象名` 。可以使用通配符。

范例：

arn:aws:s3:::bucket_name/key_name
arn:aws:s3:::examplebucket/developers/design_info.doc
arn:aws:s3:::examplebucket/*
arn:aws:s3:::*
arn:aws:s3:::example?bucket/*
arn:aws:s3:::bucket_name/developers/${aws:username}/

三、MinIO 内置 Policy 范例

consoleadmin

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "admin:*"
            ]
        },
        {
            "Effect": "Allow",
            "Action": [
                "kms:*"
            ]
        },
        {
            "Effect": "Allow",
            "Action": [
                "s3:*"
            ],
            "Resource": [
                "arn:aws:s3:::*"
            ]
        }
    ]
}

writeonly

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

readonly

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "s3:GetBucketLocation",
                "s3:GetObject"
            ],
            "Resource": [
                "arn:aws:s3:::*"
            ]
        }
    ]
}

readwrite

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

diagnostics

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "admin:Prometheus",
                "admin:ServerInfo",
                "admin:ServerTrace",
                "admin:TopLocksInfo",
                "admin:BandwidthMonitor",
                "admin:ConsoleLog",
                "admin:OBDInfo",
                "admin:Profiling"
            ],
            "Resource": [
                "arn:aws:s3:::*"
            ]
        }
    ]
}