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Introduction

This chapter describes fine-grained permissions management for your EVS. If your HUAWEI CLOUD account does not need individual EVS users, then you may skip over this chapter.

A policy is a set of permissions defined in JSON format. By default, new IAM users do not have any permissions assigned. You need to add a user to one or more groups, and assign permissions policies to these groups. The user then inherits permissions from the groups it is a member of. This process is called authorization. After authorization, the user can perform specified operations on EVS based on the permissions. For more information about policy syntax and for example policies, see Permissions Management.

There are fine-grained policies and role-based access control (RBAC) policies. An RBAC policy consists of permissions for an entire service. Users in a group with such a policy assigned are granted all of the permissions required for that service. A fine-grained policy consists of API-based permissions for operations on specific resource types. Fine-grained policies, as the name suggests, allow for more fine-grained control than RBAC policies.

NOTE:
  • Fine-grained policies are currently available for open beta testing. You can apply to use the fine-grained access control function free of charge. For more information, see Applying for Fine-Grained Access Control.
  • If you want to allow or deny the access to an API, fine-grained authorization is a good choice.

A HUAWEI CLOUD account has all of the permissions required to call all APIs, but IAM users must have the required permissions specifically assigned. The permissions required for calling an API are determined by the actions supported by the API. Only users that have been granted permissions allowing the actions can call the API successfully. For example, if an IAM user queries EVS disks using an API, the user must have been granted permissions that allow the evs:volumes:list action.

Supported Actions

Operations supported by a fine-grained policy are specific to APIs. The following describes the headers of the action tables provided in this chapter:

  • Permissions: Defined by actions in a custom policy.
  • Actions: Added to a custom policy to control permissions for specific operations.
  • Authorization Scope: A custom policy can be applied to IAM projects or enterprise projects or both. Policies that contain actions supporting both IAM and enterprise projects can be assigned to user groups and take effect in both IAM and Enterprise Management. Policies that only contain actions supporting IAM projects can be assigned to user groups and only take effect for IAM. Such policies will not take effect if they are assigned to user groups in Enterprise Project. For details about the differences between IAM and enterprise projects, see Differences Between IAM Projects and Enterprise Projects.
  • APIs: REST APIs that can be called in a custom policy.

EVS supports the following actions that can be defined in custom policies:

  • API version query actions, including actions supported by EVS's version query APIs, such as the APIs for querying API versions.
  • Disk actions, including actions supported by EVS's disk APIs, such as the APIs for creating a disk, querying disks, deleting a disk, and updating a disk.
  • Disk actions' actions, including actions supported by EVS's disk actions, such as the APIs for expanding the capacity of a disk, exporting a disk as an image, and setting read-only flag for a disk.
  • Snapshot actions, including actions supported by EVS's snapshot APIs, such as the APIs for creating a snapshot, querying snapshots, updating a snapshot, and deleting a snapshot.
  • Tag actions, including actions supported by EVS's tag APIs, such as the APIs for deleting tags by key, batch adding tags, batch deleting tags, and querying tags.
  • Disk transfer actions, including actions supported by EVS's disk transfer APIs, such as the APIs for creating a disk transfer, querying disk transfers, accepting a disk transfer, and deleting a disk transfer.