Role/Policy-based Authorization (Old IAM Version)

Prerequisites

• Before granting permissions to user groups, learn about system-defined permissions for UCS. To grant permissions for other services, learn about all system-defined permissions supported by IAM.
• A user with the Security Administrator role (for example, your account) has all IAM permissions except role switching. Only these users can view user groups and their permissions on the Permissions page on the UCS console.

Configuration Description

On the UCS console, when you choose Permissions > Add Permission to create a user or user group, you will be directed to the IAM console to complete the process. After the user or user group is created and the permissions are configured, you can view the information on the Permissions page of the cluster or fleet. This section describes the operations in IAM.

Process Flow

Figure 1 Process of granting UCS permissions

1. Create a user group and grant it permissions.

   On the IAM console, create a user group and grant it UCS read-only permissions (UCS ReadOnlyAccess as an example).

2. Create an IAM user and add it to the user group.

   On the IAM console, create a user and add it to the user group created in 1.

3. Log in as the IAM user and verify permissions.

   In the authorized region, perform the following operations:

   • Choose Service List > Ubiquitous Cloud Native Service. In the navigation pane, choose Infrastructure > Fleets. Create a fleet or register a cluster. If a message appears indicating that you have insufficient permissions to perform the operation, the UCS ReadOnlyAccess policy is in effect.
   • Choose another service (such as Elastic Cloud Server) from Service List. If a message appears indicating that you have insufficient permissions to access the service, the UCS ReadOnlyAccess policy is in effect.

System-defined Roles

Roles are a coarse-grained authorization strategy that defines permissions by job responsibility. Only a limited number of service-level roles are available for authorization. Roles are not ideal for fine-grained authorization and least privilege access.

The system-defined role preset for UCS in IAM is UCS Administrator. When you grant permissions to a user group using this role, you also need to attach any existing role dependencies, such as Tenant Guest, Server Administrator, ELB Administrator, OBS Administrator, SFS Administrator, APM FullAccess, and SWR Admin. For more information about role dependencies, see System Permissions.

System-defined Policies

The system-defined policies preset for UCS in IAM include UCS FullAccess, UCS CommonOperations, UCS CIAOperations, and UCS ReadOnlyAccess.

• UCS FullAccess: administrator permissions for UCS. Users with these permissions can perform all operations on UCS, including creating permission policies and security policies.
  

  UCS FullAccess does not have the RBAC permissions of CCE clusters. Users need to go to the Permissions page to grant permissions for CCE clusters.

• UCS CommonOperations: common operation permissions for UCS. Users with these permissions can create workloads, distribute traffic, and perform other operations.
• UCS CIAOperations: administrator permissions for UCS CIA.
• UCS ReadOnlyAccess: read-only permissions for UCS (excluding CIA).

You can check the content of a system-defined policy to learn about its supported actions. An action is in the format of {service-name}:{resource-type}:{action}. The wildcard (*) is allowed, indicating all actions.

The following shows the content of the UCS FullAccess policy. This policy contains all permissions for UCS, Cloud Container Engine (CCE), and SoftWare Repository for Container (SWR), and operation permissions on some resources of Application Operations Management (AOM), Simple Message Notification (SMN), Domain Name Service (DNS), and other services.

{
    "Version": "1.1",
    "Statement": [
        {
            "Action": [
                "ucs:*:*",
                "cce:*:*",
                "swr:*:*",
                "aom:*:get",
                "aom:*:list",
                "smn:*:list",
                "dns:*:get*",
                "dns:*:list*",
                "dns:*:get",
                "dns:*:list",
                "dns:recordset:create",
                "dns:recordset:delete",
                "dns:recordset:update",
                "dns:tag:get",
                "lts:*:get",
                "lts:*:list",
                "apm:*:get",
                "apm:*:list",
                "vpcep:epservices:*",
                "vpcep:connections:*",
                "vpcep:endpoints:*",
                "elb:*:get",
                "elb:*:list",
                "vpc:*:get",
                "vpc:*:list",
                "ief:*:get",
                "ief:*:list",
                "cgs:images:operate",
                "cgs:*:get",
                "cgs:*:list"
            ],
            "Effect": "Allow"
        }
    ]
}

Least-Privilege Permissions for UCS Functions

Services on Huawei Cloud are interdependent, so UCS depends on other cloud services to implement some functions (such as image repositories and domain name resolution). The preceding four system-defined policies are often used together with the roles or policies of other cloud services for refined authorization. When granting permissions to IAM users, the administrator must comply with the principle of least privilege. Table 3 lists the least-privilege permissions required by the Administrator, Operator, and Viewer roles to use UCS functions.

• If your Huawei Cloud account logs in to the UCS console for the first time, you need to grant permissions to the account. UCS will create an agency named ucs_admin_trust for you in IAM. Do not delete or modify the agency.
• If no permissions are granted to the user group that an IAM user belongs to, access to the UCS console will be denied. Grant permissions by referring to Table 3.
• UCS FullAccess does not have the RBAC permissions of CCE clusters. You need to go to the Permissions page to grant permissions for CCE clusters as described in the following table.

Custom Policies

You can create custom policies to supplement the system-defined policies of UCS. For details about actions supported in custom policies, see Permissions and Supported Actions.

To create a custom policy, choose either visual editor or JSON.

• Visual editor: Select cloud services, actions, resources, and request conditions. This does not require knowledge of policy grammar.
• JSON: Create a JSON policy or edit an existing one.

For details, see Creating a Custom Policy. The following lists examples of common UCS custom policies.

Examples:

• Example 1: Grant permission to create a cluster.

  {
      "Version": "1.1",
      "Statement": [
          {
              "Effect": "Allow",
              "Action": [
                  "ucs:clusters:create"
              ]
          }
      ]
  }

• Example 2: Grant permission to deny cluster deletion.

  A policy with only "Deny" permissions must be used together with other policies. If the permissions granted to an IAM user contain both "Allow" and "Deny", the "Deny" permissions take precedence over the "Allow" permissions.

  Assume that you want to grant the permissions of the UCSFullAccess policy to a user but want to prevent the user from deleting clusters (ucs:clusters:delete). You can create a custom policy for denying cluster deletion, and attach this policy together with the UCSFullAccess policy to the user. As an explicit "Deny" policy overrides any "Allow" policy, the user can perform all operations on clusters excepting deleting them. Example policy denying cluster deletion:

  {
      "Version": "1.1",
      "Statement": [
          {
              "Effect": "Deny",
              "Action": [
                  "ucs:clusters:delete"
              ]
          }
      ]
  }

• Example 3: Create a custom policy containing multiple actions.

  A custom policy can contain the actions of one or multiple services that are of the same type (global or project-level). Example policy containing multiple actions:

  {
      "Version": "1.1",
      "Statement": [
          {
              "Effect": "Allow",
              "Action": [
                  "ucs:clustergroups:create",
                  "ucs:ciaEvents:update",
                  "ucs:addonTemplates:delete"
              ]
          },
          {
              "Effect": "Allow",
              "Action": [
                  "obs:bucket:GetBucketInventoryConfiguration",
                  "obs:bucket:CreateBucket"
              ]
          }
      ]
  }