Overview of Vault

Oracle Cloud Infrastructure Vault is a managed service that lets you centrally manage the encryption keys that protect your data and the secret credentials that you use to securely access resources. Vaults securely store master encryption keys and secrets that you might otherwise store in configuration files or in code. Specifically, depending on the protection mode, keys are either stored on the server or they are stored on highly available and durable hardware security modules (HSM) that meet Federal Information Processing Standards (FIPS) 140-2 Security Level 3 security certification.

The key encryption algorithms that the Vault service supports includes the Advanced Encryption Standard (AES), the Rivest-Shamir-Adleman (RSA) algorithm, and the elliptic curve digital signature algorithm (ECDSA). You can create and use AES symmetric keys and RSA asymmetric keys for encryption and decryption. You can also use RSA or ECDSA asymmetric keys for signing digital messages.

You can use the Vault service to create and manage the following resources:

  • Vaults
  • Keys
  • Secrets

You can use the Vault service to exercise the following lifecycle management features for vaults, master encryption keys, and secrets, helping you to control these resources and access to them:

  • Create vaults
  • Create or import cryptographic material as master encryption keys
  • Create secrets to store secret credentials
  • Enable or disable master encryption keys for use in cryptographic operations
  • Rotate keys to generate new cryptographic material
  • Export key or vault metadata to a backup that you can restore and use again later
  • Continuously replicate a vault and its keys to another region in the realm
  • Update secrets with new secret contents
  • Specify which secret version is currently in use through promotion
  • Configure rules to govern the management and use of secrets
  • Tag vaults, master encryption keys, or secrets to add metadata to resources
  • Delete vaults, keys, or secrets when they're no longer needed

Regarding the use of master encryption keys, you can do the following:

  • Use keys for encryption and decryption of data while at rest or in transit
  • Use keys to sign messages and verify signed messages
  • Assign keys to supported Oracle Cloud Infrastructure resources, including, but not limited to, buckets and file systems
  • Generate data encryption keys

The following services integrate with the Vault service to support the use of customer-managed keys to encrypt data in their respective, specified resources:

  • Oracle Cloud Infrastructure Block Volume: block and boot volumes
  • Oracle Cloud Infrastructure Container Engine for Kubernetes: Kubernetes secrets at rest in the etcd key-value store (when creating new clusters only)
  • Oracle Cloud Infrastructure Database: Autonomous Container Databases on dedicated Autonomous Exadata Infrastructure and Exadata Databases (without Oracle Data Guard enabled)
  • Oracle Cloud Infrastructure File Storage: file systems
  • Oracle Cloud Infrastructure Object Storage: buckets
  • Oracle Cloud Infrastructure Streaming: stream pools

In addition, integration with Oracle Cloud Infrastructure Identity and Access Management (IAM) lets you control who and what services can access which keys and secrets and what they can do with those resources. Oracle Cloud Infrastructure Audit integration gives you a way to monitor key and secret usage. Audit tracks administrative actions on vaults, keys, and secrets.

Key and Secret Management Concepts

The following concepts are key to understanding the Vault service.

VAULTS
Vaults are logical entities where the Vault service creates and durably stores keys and secrets. The type of vault you have determines features and functionality such as degrees of storage isolation, access to management and encryption, scalability, and the ability to back up. The type of vault you have also affects pricing. You cannot change a vault's type after you create the vault.
The Vault service offers different vault types to accommodate your organization's needs and budget. All vault types ensure the security and integrity of the encryption keys and secrets that vaults store. A virtual private vault is an isolated partition on a hardware security module (HSM). Vaults otherwise share partitions on the HSM with other vaults.
Virtual private vaults include 1000 key versions by default. If you don't require the greater degree of isolation or the ability to back up the vault, you don't need a virtual private vault. Without a virtual private vault, you can manage costs by paying for key versions individually, as you need them. (Key versions count toward your key limit and costs. A key always contains at least one active key version. Similarly, a secret always has at least one secret version. However, limits on secrets apply to the tenancy, rather than a vault.)
The Vault service designates vaults as an Oracle Cloud Infrastructure resource.
KEYS
Keys are logical entities that represent one or more key versions, each of which contains cryptographic material. A key's cryptographic material is generated for a specific algorithm that lets you use the key for encryption or in digital signing. When used for encryption, a key or key pair encrypts and decrypts data, protecting the data where the data is stored or while the data is in transit. With an AES symmetric key, the same key encrypts and decrypts data. With an RSA asymmetric key, the public key encrypts data and the private key decrypts data.
You can use AES keys in encryption and decryption, but not in digital signing. RSA keys, however, can be used not only to encrypt and decrypt data, but also to digitally sign data and verify the authenticity of signed data. You can use ECDSA keys in digital signing, but not to encrypt or decrypt data.
When processed as part of an encryption algorithm, a key specifies how to transform plaintext into ciphertext during encryption and how to transform ciphertext into plaintext during decryption. When processed as part of a signing algorithm, together, the private key of an asymmetric key and a message produce a digital signature that accompanies the message in transit. When processed as part of a signature verifying algorithm by the recipient of the signed message, the message, signature, and the public key of the same asymmetric key confirm or deny the authenticity and integrity of the message.
Conceptually, the Vault service recognizes three types of encryption keys: master encryption keys, wrapping keys, and data encryption keys.
The encryption algorithms that the Vault service supports for master encryption keys include AES, RSA, and ECDSA. You can create AES, RSA, or ECDSA master encryption keys by using the Console, CLI, or API. When you create a master encryption key, the Vault service can either generate the key material internally or you can import the key material to the service from an external source. (Support for importing key material depends on the encryption algorithm of the key material.) When you create master encryption keys, you create them in a vault, but where a key is stored and processed depends on its protection mode.
Master encryption keys can have one of two protection modes: HSM or software. A master encryption key protected by an HSM is stored on an HSM and cannot be exported from the HSM. All cryptographic operations involving the key also happen on the HSM. Meanwhile, a master encryption key protected by software is stored on a server and, therefore, can be exported from the server to perform cryptographic operations on the client instead of on the server. While at rest, the software-protected key is encrypted by a root key on the HSM. For a software-protected key, any processing related to the key happens on the server. A key's protection mode affects pricing and cannot be changed after you create the key.
After you create your first symmetric master encryption key, you can then use the API to generate data encryption keys that the Vault service returns to you. Some services can also use a symmetric master encryption key to generate their own data encryption keys.
A type of encryption key that comes included with each vault by default is a wrapping key. A wrapping key is a 4096-bit asymmetric encryption key based on the RSA algorithm. The public and private key pair do not count against service limits. They also do not incur service costs. You use the public key as the key encryption key when you need to wrap key material for import into the Vault service. You cannot create, delete, or rotate wrapping keys.
The Vault service recognizes master encryption keys as an Oracle Cloud Infrastructure resource.
KEY VERSIONS
Each master encryption key is automatically assigned a key version. When you rotate a key, the Vault service generates a new key version. The Vault service can generate the key material for the new key version or you can import your own key material.
Periodically rotating keys limits the amount of data encrypted or signed by one key version. If a key is ever compromised, key rotation thus reduces the risk. A key’s unique, Oracle-assigned identifier, called an Oracle Cloud ID (OCID), remains the same across rotations, but the key version lets the Vault service seamlessly rotate keys to meet any compliance requirements you might have.
Although you can't use an older key version for encryption after you rotate a key, the key version remains available to decrypt any data that it previously encrypted. If you rotate an asymmetric key, the public key can no longer be used to encrypt data, but the private key remains available to decrypt data previously encrypted by the public key. When you rotate an asymmetric key used in digital signing, you can no longer use the private key version to sign data, but the public key version remains available to verify the digital signature of data previously signed by the older private key version.
For symmetric keys, you do not need to track which key version was used to encrypt what data because the key's ciphertext contains the information that the service needs for decryption purposes. Through rotations of asymmetric keys, however, you must track which key version was used to encrypt or sign what data. With asymmetric keys, the key's ciphertext does not contain the information that the service requires for decryption or verification.
With AES symmetric keys, each key version counts as one key version when calculating service limits usage. However, with RSA and ECDSA asymmetric keys, each key version counts as two when calculating usage against service limits because an asymmetric key has both a public key and private key. (Asymmetric keys are also known as key pairs.)
HARDWARE SECURITY MODULES
When you create an AES symmetric master encryption key with the protection mode set to HSM, the Vault service stores the key version within a hardware security module (HSM) to provide a layer of physical security. (When you create a secret, secret versions are base64-encoded and encrypted by a master encryption key, but are not stored within the HSM.) After you create the resources, the service maintains copies of any given key version or secret version within the service infrastructure to provide resilience against hardware failures. Key versions of HSM-protected keys are not otherwise stored anywhere else and cannot be exported from an HSM.
When you create an RSA or ECDSA asymmetric master encryption key with the protection mode set to HSM, the Vault service stores the private key within an HSM and does not allow its export from the HSM. However, you can download the public key.
The Vault service uses HSMs that meet Federal Information Processing Standards (FIPS) 140-2 Security Level 3 security certification. This certification means that the HSM hardware is tamper-evident, has physical safeguards for tamper-resistance, requires identity-based authentication, and deletes keys from the device when it detects tampering.
ENVELOPE ENCRYPTION
The data encryption key used to encrypt your data is, itself, encrypted with a master encryption key. This concept is known as envelope encryption. Oracle Cloud Infrastructure services do not have access to the plaintext data without interacting with the Vault service and without access to the master encryption key that is protected by Oracle Cloud Infrastructure Identity and Access Management (IAM). For decryption purposes, integrated services like Object Storage, Block Volume, and File Storage store only the encrypted form of the data encryption key.
SECRETS
Secrets are credentials such as passwords, certificates, SSH keys, or authentication tokens that you use with Oracle Cloud Infrastructure services. Storing secrets in a vault provides greater security than you might achieve storing them elsewhere, such as in code or configuration files. You can retrieve secrets from the Vault service when you need them to access resources or other services.
You can create secrets by using the Console, CLI, or API. Secret contents for a secret are imported to the service from an external source. The Vault service stores secrets in vaults.
The Vault service supports secrets as an Oracle Cloud Infrastructure resource.
SECRET VERSIONS
Each secret is automatically assigned a secret version. When you rotate secret, you provide new secret contents to the Vault service to generate a new secret version. Periodically rotating secret contents reduces the impact in case a secret is exposed. A secret’s unique, Oracle-assigned identifier, called an Oracle Cloud ID (OCID), remains the same across rotations, but the secret version lets the Vault service rotate secret contents to meet any rules or compliance requirements you might have. Although you can't use an older secret version's contents after you rotate it if you have a rule configured preventing secret reuse, the secret version remains available and is marked with a rotation state other than "current". For more information about secret versions and their rotation states, see Secret Versions and Rotation States.
SECRET BUNDLES
A secret bundle consists of the secret contents, properties of the secret and secret version (such as version number or rotation state), and user-provided contextual metadata for the secret. When you rotate a secret, you create a new secret version, which also includes a new secret bundle version.

Regions and Availability Domains

The Vault service is available in all Oracle Cloud Infrastructure commercial regions. See About Regions and Availability Domains for the list of available regions, along with associated locations, region identifiers, region keys, and availability domains.

Unlike some Oracle Cloud Infrastructure services, however, the Vault service does not have one regional endpoint for all API operations. The service has one regional endpoint for the provisioning service that handles create, update, and list operations for vaults. For create, update, and list operations for keys, service endpoints are distributed across multiple independent clusters. Service endpoints for secrets are distributed further still across different independent clusters.

Because the Vault service has public endpoints, you can directly use data encryption keys generated by the service for cryptographic operations in your applications. However, if you want to use master encryption keys with a service that has integrated with Vault, you can do so only when the service and the vault that holds the key both exist within the same region. Different endpoints exist for key management operations, key cryptographic operations, secret management operations, and secret retrieval operations. For more information, see Oracle Cloud Infrastructure API Documentation

The Vault service maintains copies of encryption keys and secrets across all availability domains within a region. This replication makes it possible for the Vault service to produce keys or secrets upon request, even when an availability domain is unavailable.

Private Access to Vault

The Vault service supports private access from Oracle Cloud Infrastructure resources in a virtual cloud network (VCN) through a service gateway. Setting up and using a service gateway on a VCN lets resources (such as the instances that your encrypted volumes are attached to) access public Oracle Cloud Infrastructure services such as the Vault service without exposing them to the public internet. No internet gateway is required and resources can be in a private subnet and use only private IP addresses. For more information, see Access to Oracle Services: Service Gateway.

Resource Identifiers

The Vault service supports vaults, keys, and secrets as Oracle Cloud Infrastructure resources. Most types of Oracle Cloud Infrastructure resources have a unique, Oracle-assigned identifier called an Oracle Cloud ID (OCID). For information about the OCID format and other ways to identify your resources, see Resource Identifiers.

Ways to Access Oracle Cloud Infrastructure

You can access Oracle Cloud Infrastructure using the Console (a browser-based interface) or the REST API. Instructions for the Console and API are included in topics throughout this guide. For a list of available SDKs, see Software Development Kits and Command Line Interface.

To access the Console, you must use a supported browser. You can use the Console link at the top of this page to go to the sign-in page. You will be prompted to enter your cloud tenant, your user name, and your password.

For general information about using the API, see REST APIs.

Authentication and Authorization

Each service in Oracle Cloud Infrastructure integrates with IAM for authentication and authorization, for all interfaces (the Console, SDK or CLI, and REST API).

An administrator in your organization needs to set up groups , compartments , and policies  that control which users can access which services, which resources, and the type of access. For example, the policies control who can create new users, create and manage the cloud network, launch instances, create buckets, download objects, etc. For more information, see Getting Started with Policies. For specific details about writing policies for each of the different services, see Policy Reference.

If you’re a regular user (not an administrator) who needs to use the Oracle Cloud Infrastructure resources that your company owns, contact your administrator to set up a user ID for you. The administrator can confirm which compartment or compartments you should be using.

Limits on Vault Resources

See Service Limits for a list of applicable limits and instructions for requesting a limit increase. To set compartment-specific limits on a resource or resource family, administrators can use compartment quotas.

For instructions to view your usage level against the tenancy's resource limits, see Viewing Your Service Limits, Quotas, and Usage. You can also get each individual vault's usage against key limits by viewing key and key version counts in the vault details.