Elastic Volume Service (EVS)

IAM provides system-defined identity policies to define common actions supported by cloud services. You can also create custom identity policies using the actions supported by cloud services for more refined access control.

In addition to IAM, the Organizations service provides Service Control Policies (SCPs) to set access control policies.

SCPs do not actually grant any permissions to a principal. They only set the permissions boundary for the principal. When SCPs are attached to a member account or an organizational unit (OU), they do not directly grant permissions to that member account or OU. Instead, the SCPs just determine what permissions are available for that member account or the member accounts under that OU. The granted permissions can be applied only if they are allowed by the SCPs.

To learn more about how IAM is different from Organizations for access control, see What Are the Differences in Access Control Between IAM and Organizations?

This section describes the elements used by IAM custom identity policies and Organizations SCPs. The elements include actions, resources, and conditions.

For details about how to use these elements to create an IAM custom identity policy, see Creating a Custom Identity Policy.
For details about how to use these elements to create a custom SCP, see Creating an SCP.

Actions

Actions are specific operations that are allowed or denied in an identity policy.

The Access Level column describes how the action is classified (List, Read, or Write). This classification helps you understand the level of access that an action grants when you use it in an identity policy.
The Resource Type column indicates whether the action supports resource-level permissions.
- You can use a wildcard (*) to indicate all resource types. If this column is empty (-), the action does not support resource-level permissions and you must specify all resources ("*") in your identity policy statements.
- If this column includes a resource type, you must specify the URN in the Resource element of your statements.
- Required resources are marked with asterisks (*) in the table. If you specify a resource in a statement using this action, then it must be of this type.
For details about the resource types defined by EVS, see Resources.
The Condition Key column contains keys that you can specify in the Condition element of an identity policy statement.
- If the Resource Type column has values for an action, the condition key takes effect only for the listed resource types.
- If the Resource Type column is empty (-) for an action, the condition key takes effect for all resources that action supports.
- If the Condition Key column is empty (-) for an action, the action does not support any condition keys.
For details about the condition keys defined by EVS, see Conditions.
The Alias column lists the policy actions that are configured in identity policies. With these actions, you can use APIs for identity policy-based authorization. For details, see Policies and Identity Policies.

The following table lists the actions that you can define in identity policy statements for EVS.

**Table 1** Actions supported by EVS
Action	Description	Access Level	Resource Type (*: required)	Condition Key	Alias
evs::enableEncryptionByDefault	Grants permission to enable default encryption.	Write	-	-	-
evs::disableEncryptionByDefault	Grants permission to disable default encryption.	Write	-	-	-
evs::getEncryptionByDefault	Grants permission to query default encryption.	Write	-	-	-
evs::modifyDefaultKmsKeyId	Grants permission to change the default key.	Write	-	evs:KmsKeyId	-
evs::resetDefaultKmsKeyId	Grants permission to reset the default key to evs/default.	Write	-	-	-
evs::getDefaultKmsKeyId	Grants permission to query the default key.	Write	-	-	-
evs:volumes:create	Grants permission to create disks.	Write	volume *	-	-
evs:volumes:create	Grants permission to create disks.	Write	-	g:RequestTag/<tag-key> g:TagKeys g:EnterpriseProjectId evs:Encrypted cbr:VaultId evs:KmsKeyId evs:ImageId evs:BackupId evs:SnapshotId evs:AvailabilityZone evs:VolumeType evs:VolumeSize evs:VolumeIops evs:VolumeThroughput evs:ChargingMode evs:ServerServiceType ecs:ServerId bms:ServerId evs:SourceAvailabilityZone	-
evs:volumes:list	Grants permission to list disks.	List	-	g:EnterpriseProjectId	-
evs:volumes:get	Grants permission to query disks.	Read	volume *	g:ResourceTag/<tag-key> g:EnterpriseProjectId	-
evs:volumes:delete	Grants permission to delete disks.	Write	volume *	g:ResourceTag/<tag-key> g:EnterpriseProjectId	-
evs:volumes:update	Grants permission to update disks.	Write	volume *	g:ResourceTag/<tag-key> g:EnterpriseProjectId	-
evs:volumes:resize	Grants permission to expand disk capacities.	Write	volume *	g:ResourceTag/<tag-key> g:EnterpriseProjectId	evs:volumes:extend
evs:volumes:modifyQos	Grants permission to modify disk QoS configurations.	Write	volume *	g:ResourceTag/<tag-key> g:EnterpriseProjectId	evs:volumes:extend
evs:volumes:retype	Grants permission to change disk types.	Write	volume *	g:ResourceTag/<tag-key> g:EnterpriseProjectId	-
evs:volumes:revert	Grants permission to recover disks from the recycle bin.	Write	volume *	g:ResourceTag/<tag-key> g:EnterpriseProjectId	-
evs:recycle_policy:get	Grants permission to query the recycle bin policy.	Read	-	-	-
evs:recycle_policy:update	Grants permission to update the recycle bin policy.	Write	-	-	-
evs:volumes:changeChargeMode	Grants permission to change the disk billing mode.	Write	volume *	g:ResourceTag/<tag-key> g:EnterpriseProjectId	-
evs:snapshots:create	Grants permission to create snapshots for disks.	Write	snapshot *	-	-
			volume *	g:ResourceTag/<tag-key> g:EnterpriseProjectId
			-	evs:SourceAvailabilityZone evs:AvailabilityZone
evs:snapshots:list	Grants permission to list snapshots.	List	-	g:EnterpriseProjectId	-
evs:snapshots:get	Grants permission to query snapshots.	Read	-	g:EnterpriseProjectId	-
evs:snapshots:delete	Grants permission to delete snapshots.	Write	-	g:EnterpriseProjectId	-
evs:snapshots:update	Grants permission to update snapshots.	Write	-	g:EnterpriseProjectId	-
evs:snapshots:rollback	Grants permission to roll back data from snapshots.	Write	-	g:EnterpriseProjectId	-
evs:types:get	Grants permission to query disk types.	Read	-	-	-
evs:quotas:get	Grants permission to query EVS quotas.	Read	-	-	-
evs:volumes:tagResource	Grants permission to add tags to a disk.	Write	volume *	g:ResourceTag/<tag-key> g:EnterpriseProjectId	evs:volumeTags:create
evs:volumes:tagResource	Grants permission to add tags to a disk.	Write	-	g:RequestTag/<tag-key> g:TagKeys	evs:volumeTags:create
evs:volumes:unTagResource	Grants permission to delete tags from a disk.	Write	volume *	g:ResourceTag/<tag-key> g:EnterpriseProjectId	evs:volumeTags:delete
evs:volumes:unTagResource	Grants permission to delete tags from a disk.	Write	-	g:TagKeys	evs:volumeTags:delete
evs:volumes:listTags	Grants permission to query all disk tags in a project.	List	-	-	evs:volumeTags:list
evs:volumes:listTagsForResource	Grants permission to query disk tags.	Read	volume *	g:ResourceTag/<tag-key> g:EnterpriseProjectId	evs:volumeTags:getById
evs:volumes:listResourcesByTag	Grants permission to list disks by tag.	List	-	g:TagKeys	evs:volumeTags:get
evs:volumes:use	Grants permission to allow ECSs and BMSs to use EVS disks.	Write	-	g:EnterpriseProjectId	-

Each API of EVS usually supports one or more actions. Table 2 lists the supported actions and dependencies.

**Table 2** Actions and dependencies supported by EVS APIs
API	Action	Dependencies
POST /v5/{project_id}/default-encryption/enable	evs::enableEncryptionByDefault	-
POST /v5/{project_id}/default-encryption/disable	evs::disableEncryptionByDefault	-
GET /v5/{project_id}/default-encryption/status	evs::getEncryptionByDefault	-
PUT /v5/{project_id}/default-encryption/key	evs::modifyDefaultKmsKeyId	-
PUT /v5/{project_id}/default-encryption/key/reset	evs::resetDefaultKmsKeyId	-
GET /v5/{project_id}/default-encryption/key	evs::getDefaultKmsKeyId	-
POST /v2.1/{project_id}/cloudvolumes	evs:volumes:create	billing:order:pay
POST /v2/{project_id}/cloudvolumes	evs:volumes:create	-
POST /v3/{project_id}/cloudvolumes	evs:volumes:create	-
GET /v2/{project_id}/cloudvolumes/detail	evs:volumes:list	-
GET /v2/{project_id}/cloudvolumes/{volume_id}	evs:volumes:get	-
DELETE /v2/{project_id}/cloudvolumes/{volume_id}	evs:volumes:delete	-
POST /v1/{project_id}/volumes/deleted-list/batch-action	evs:volumes:delete	-
PUT /v2/{project_id}/cloudvolumes/{volume_id}	evs:volumes:update	-
POST /v2.1/{project_id}/cloudvolumes/{volume_id}/action	evs:volumes:resize	billing:order:pay
-	evs:volumes:resize	billing:order:pay
POST /v2/{project_id}/cloudvolumes/{volume_id}/action	evs:volumes:resize	-
PUT /v5/{project_id}/cloudvolumes/{volume_id}/qos	evs:volumes:modifyQos	-
POST /v2/{project_id}/volumes/{volume_id}/retype	evs:volumes:retype	billing:order:pay
POST /v2/{project_id}/cloudvolumes/unsubscribe	evs:volumes:delete	billing:subscription:unsubscribe
POST /v2/{project_id}/cloudvolumes/change-charge-mode	evs:volumes:changeChargeMode	billing:order:pay billing:subscription:renew
POST /v2/{project_id}/cloudsnapshots	evs:snapshots:create	-
GET /v2/{project_id}/cloudsnapshots/detail	evs:snapshots:list	-
GET /v2/{project_id}/cloudsnapshots/{snapshot_id}	evs:snapshots:get	-
DELETE /v2/{project_id}/cloudsnapshots/{snapshot_id}	evs:snapshots:delete	-
PUT /v2/{project_id}/cloudsnapshots/{snapshot_id}	evs:snapshots:update	-
POST /v2/{project_id}/cloudsnapshots/{snapshot_id}/rollback	evs:snapshots:rollback	-
POST /v2/{project_id}/cloudvolumes/{volume_id}/tags/action	evs:volumes:tagResource	-
POST 01 /v2/{project_id}/cloudvolumes/{volume_id}/tags/action	evs:volumes:unTagResource	-
GET /v2/{project_id}/cloudvolumes/tags	evs:volumes:listTags	-
GET /v2/{project_id}/cloudvolumes/{volume_id}/tags	evs:volumes:listTagsForResource	-
POST /v2/{project_id}/cloudvolumes/resource_instances/action	evs:volumes:listResourcesByTag	-

Resources

A resource type indicates the resources that an identity policy applies to. If you specify a resource type for any action in Table 3, the resource URN must be specified in the identity policy statements using that action, and the identity policy applies only to resources of this type. If no resource type is specified, the Resource element is marked with an asterisk (*) and the policy applies to all resources. You can also set condition keys in an identity policy to define resource types.

The following table lists the resource types that you can define in identity policy statements for EVS.

**Table 3** Resource types supported by EVS
Resource Type	URN
imageCache	evs:<region>:<account-id>:imageCache:<imageCache-id>
snapshot	evs:<region>:<account-id>:snapshot:<snapshot-id>
volume	evs:<region>:<account-id>:volume:<volume-id>

Conditions

About condition keys

A Condition element lets you specify conditions for when an identity policy is in effect. It contains condition keys and operators.

The condition key that you specify can be a global condition key or a service-specific condition key.
- Global condition keys (with the g: prefix) apply to all actions. Cloud services do not need to provide user identity information. Instead, the system automatically obtains such information and authenticates users. For details, see Global Condition Keys.
- Service-specific condition keys (with the abbreviation of a service name plus a colon as the prefix, for example, evs:) apply only to operations of EVS. For details, see Table 4.
- The number of values associated with a condition key in the request context of an API call makes the condition key single-valued or multivalued. Single-valued condition keys have at most one value in the request context of an API call. Multivalued condition keys can have multiple values in the request context of an API call. For example, a request can originate from at most one VPC endpoint, so g:SourceVpce is a single-valued condition key. You can tag resources and include multiple tag key-value pairs in a request, so g:TagKeys is a multivalued condition key.
A condition operator, condition key, and a condition value together constitute a complete condition statement. An identity policy can be applied only when its request conditions are met. For supported condition operators, see Condition operators.

Service-specific condition keys supported by EVS

The following table lists the condition keys that you can define in custom identity policies for EVS. You can include these condition keys to specify conditions for when your identity policy is in effect.

**Table 4** Service-specific condition keys supported by EVS
Service-specific Condition Key	Type	Single-valued/Multivalued	Description
evs:KmsKeyId	string	Single-valued	Filters access based on the key ID used by the disk.
evs:Encrypted	boolean	Single-valued	Filters access based on whether the disk is encrypted.
evs:KmsKeyId	string	Single-valued	Filters access based on the key ID used by the disk.
evs:ImageId	string	Single-valued	Filters access by image ID.
evs:BackupId	string	Single-valued	Filters access by backup ID.
evs:SnapshotId	string	Single-valued	Filters access by snapshot ID.
evs:AvailabilityZone	string	Single-valued	Filters access based on the AZ of the disk.
evs:SourceAvailabilityZone	string	Single-valued	Filters access by source AZ.
evs:VolumeType	string	Single-valued	Filters access by disk type.
evs:VolumeSize	numeric	Single-valued	Filters access by disk capacity.
evs:VolumeIops	numeric	Single-valued	Filters access by disk IOPS.
evs:VolumeThroughput	numeric	Single-valued	Filters access by disk throughput.
evs:ChargingMode	string	Single-valued	Filters access by disk billing mode.
evs:ServerServiceType	string	Single-valued	Filters access based on the service type of the cloud server.
evs:VolumeId	string	Single-valued	Filters access by disk ID.