What is a system policy?
A policy defines a set of permissions that are described based on the policy structure and syntax. You can use policies to describe the authorized resource sets, authorized operation sets, and authorization conditions. Alibaba Cloud Resource Access Management (RAM) provides system policies and custom policies. All system policies are created and updated by Alibaba Cloud. You can use system policies, but you cannot modify them. You can manage and update custom policies based on your business requirements. You can create, update, and delete custom policies. During service iteration, KMS adds new permissions to system policies to support new features and capabilities. The update of a system policy affects all RAM identities to which the policy is attached, including RAM users, RAM user groups, and RAM roles. For more information about RAM policies, see Policy overview.
System policies are designed for new users to quickly get started with Alibaba Cloud products on the management console, though they also enable the use of more advanced methods like API operations or CLI commands. If you are familiar with the advanced methods, we recommend that you use custom policies to implement finer-grained control on who is permitted to call what API operations, thereby improving security.
System policies can be classified into service system policies, service role policies, and service-linked role policies. Some cloud services provide only one or two of the three types of policies. For more information, see the policy types that are described in the following section.
Service system policies
AliyunKMSCryptoAdminAccess
The AliyunKMSCryptoAdminAccess policy: Provides administrative access to cryptographic keys in KMS via Management Console. It can be attached to RAM identities.
AliyunKMSCryptoUserAccess
The AliyunKMSCryptoUserAccess policy: Provides access to the cryptographic APIs of KMS. It can be attached to RAM identities.
AliyunKMSFullAccess
The AliyunKMSFullAccess policy: Provides full access to Key Management Service via Management Console. It can be attached to RAM identities.
AliyunKMSReadOnlyAccess
The AliyunKMSReadOnlyAccess policy: Provides read-only access to Key Management Service via Management Console. It can be attached to RAM identities.
AliyunKMSSecretAdminAccess
The AliyunKMSSecretAdminAccess policy: Provides administrative access to secrets in KMS via Management Console. It can be attached to RAM identities.
AliyunKMSSecretUserAccess
The AliyunKMSSecretUserAccess policy: Provides access to retrieve the secrets in KMS. It can be attached to RAM identities.
Service role policies
AliyunKMSManageRAMCredentialsRolePolicy
The AliyunKMSManageRAMCredentialsRolePolicy policy is the dedicated authorization policy of the AliyunKMSManageRAMCredentialsRole service role. By default, kms uses this role to manage the user's RAM credentials. Do not attach this policy to a RAM identity other than the service role. If a service provides precise authorization capabilities, refer to the documentation provided by the service.
Service-linked role policies
AliyunServiceRolePolicyForKMSSecretsManagerForPolarDB
KMS assumes the AliyunServiceRolePolicyForKMSSecretsManagerForPolarDB service-linked role to access the resources in other cloud services. The AliyunServiceRolePolicyForKMSSecretsManagerForPolarDB policy is the dedicated authorization policy of the AliyunServiceRoleForKMSSecretsManagerForPolarDB service-linked role. This policy is defined and used by KMS. You cannot modify or delete the policy. Do not attach this policy to a RAM identity other than the service-linked role.
AliyunServiceRolePolicyForKMSSecretsManagerForPolarDB
AliyunServiceRolePolicyForKMSSecretsManagerForRedis
KMS assumes the AliyunServiceRolePolicyForKMSSecretsManagerForRedis service-linked role to access the resources in other cloud services. The AliyunServiceRolePolicyForKMSSecretsManagerForRedis policy is the dedicated authorization policy of the AliyunServiceRoleForKMSSecretsManagerForRedis service-linked role. This policy is defined and used by KMS. You cannot modify or delete the policy. Do not attach this policy to a RAM identity other than the service-linked role.
References
By default, RAM identities do not have any permissions. RAM identities can access cloud resources within an Alibaba Cloud account only after an account administrator grants the required permissions to the RAM identities. To ensure resource security, we recommend that you grant only the required permissions to the RAM identities based on the principle of least privilege. For more information, see the following topics: