docs/source/includes/common/common-minio-kes.rst

Enabling on a MinIO deployment automatically encrypts the backend data for that deployment using the default encryption key.

MinIO requires access to KES and the root KMS to decrypt the backend and start normally. You cannot disable KES later or "undo" the configuration at a later point.

This procedure provides instructions for modifying the startup environment variables of a MinIO deployment to enable via KES and the root KMS.

For instructions on new production deployments, see the Multi-Node Multi-Drive (Distributed) <minio-mnmd> tutorial. For instructions on new local or evaluation deployments, see the Single-Node Single-Drive <minio-snsd> tutorial.

When creating the environment file for the deployment, pause and switch back to this tutorial to include the necessary environment variables to support .

For existing MinIO Deployments, you can modify the existing environment file and restart the deployment as instructed during this procedure.

The following commands create two TLS certificates that expire within 30 days of creation:

• A TLS certificate for KES to secure communications between it and the Vault deployment
• A TLS certificate for MinIO to perform mTLS authentication to KES.

Use Caution in Production Environments

DO NOT use the TLS certificates generated as part of this procedure for any long-term development or production environments.

Defer to organization/industry best practices around TLS certificate generation and management. A complete guide to creating valid certificates (e.g. well-formed, current, and trusted) is beyond the scope of this procedure.

# These commands output keys to |kescertpath|
# and |miniocertpath| respectively

kes identity new kes_server \
  --key  |kescertpath|/kes-server.key  \
  --cert |kescertpath|/kes-server.cert  \
  --ip   "127.0.0.1"  \
  --dns  localhost

kes identity new minio_server \
  --key  |miniocertpath|/minio-kes.key  \
  --cert |miniocertpath|/minio-kes.cert  \
  --ip   "127.0.0.1"  \
  --dns  localhost

The --ip and --dns parameters set the IP and DNS SubjectAlternativeName for the certificate. The above example assumes that all components (Vault, MinIO, and KES) deploy on the same local host machine accessible via localhost or 127.0.0.1. You can specify additional IP or Hostnames based on the network configuration of your local host.

Run the following command in a terminal or shell to start the MinIO server as a foreground process.

export MINIO_CONFIG_ENV_FILE=|minioconfigpath|/minio
minio server --console-address :9090

Run the following commands in a terminal or shell to start the KES server as a foreground process:

sudo setcap cap_ipc_lock=+ep $(readlink -f $(which kes))

kes server --auth=off --config=|kesconfigpath|/kes-config.yaml

The first command allows to use the mlock system call without running as root. mlock ensures the OS does not write in-memory data to a drive (swap memory) and mitigates the risk of cryptographic operations being written to unsecured drive at any time. KES 0.21.0 and later automatically detect and enable mlock if supported by the host OS. Versions 0.20.0 and earlier required specifying the --mlock argument to KES.

The second command starts the KES server in the foreground using the configuration file created in the last step. The --auth=off disables strict validation of client TLS certificates. Using self-signed certificates for either the MinIO client or the root KMS server requires specifying this option.

listens on port 7373 by default. You can monitor the server logs from the terminal session. If you run without tying it to the current shell session (e.g. with nohup), use that method's associated logging system (e.g. nohup.txt).

MinIO requires that the exist on the root KMS before performing operations using that key. Use kes key create or mc admin kms key create to add a new for use with .

The following command uses the kes key create command to add a new External Key (EK) stored on the root KMS server for use with encrypting the MinIO backend.

export KES_SERVER=https://127.0.0.1:7373
export KES_CLIENT_KEY=|miniocertpath|/minio-kes.key
export KES_CLIENT_CERT=|miniocertpath|/minio-kes.cert

kes key create -k encrypted-bucket-key

Add the following lines to the MinIO Environment file on each MinIO host. See the tutorials for minio-snsd, minio-snmd, or minio-mnmd for more detailed descriptions of a base MinIO environment file.

# Add these environment variables to the existing environment file

MINIO_KMS_KES_ENDPOINT=https://HOSTNAME:7373
MINIO_KMS_KES_CERT_FILE=|miniocertpath|/minio-kes.cert
MINIO_KMS_KES_KEY_FILE=|miniocertpath|/minio-kes.key

# Allows validation of the KES Server Certificate (Self-Signed or Third-Party CA)
# Change this path to the location of the KES CA Path
MINIO_KMS_KES_CAPATH=|kescertpath|/kes-server.cert

# Sets the default KMS key for the backend and SSE-KMS/SSE-S3 Operations)
MINIO_KMS_KES_KEY_NAME=minio-backend-default-key

# Optional, defines the name for the KES server enclave to use.
MINIO_KMS_KES_ENCLAVE=<name>

Replace HOSTNAME with the IP address or hostname of the KES server. If the MinIO server host machines cannot resolve or reach the specified HOSTNAME, the deployment may return errors or fail to start.

• If using a single KES server host, specify the IP or hostname of that host
• If using multiple KES server hosts, specify a comma-separated list of IPs or hostnames of each host

MinIO uses the MINIO_KMS_KES_KEY_NAME key for the following cryptographic operations:

• Encrypting the MinIO backend (IAM, configuration, etc.)
• Encrypting objects using SSE-KMS <minio-encryption-sse-kms> if the request does not include a specific .
• Encrypting objects using SSE-S3 <minio-encryption-sse-s3>.

MinIO uses the MINIO_KMS_KES_ENCLAVE key to define the name of the KES enclave to use.

• Replace <name> with the name of the enclave to use.

• If not defined, MinIO does not send any enclave information. This may result in using the default enclave for stateful KES servers.

  A KES enclave provides an isolated space for its associated keys separate from other enclaves on a stateful KES server.

The minio-kes certificates enable mTLS between the MinIO deployment and the KES server only. They do not otherwise enable TLS for other client connections to MinIO.

You can use either the MinIO Console or the MinIO mc CLI to enable bucket-default SSE-KMS with the generated key:

MinIO Console

Open the MinIO Console by navigating to http://127.0.0.1:9090 in your preferred browser and logging in with the root credentials specified to the MinIO container. If you deployed MinIO using a different Console listen port, substitute 9090 with that port value.

Once logged in, create a new Bucket and name it to your preference. Select the Gear gear icon to open the management view.

Select the pencil pencil icon next to the Encryption field to open the modal for configuring a bucket default SSE scheme.

Select SSE-KMS, then enter the name of the key created in the previous step.

Once you save your changes, try to upload a file to the bucket. When viewing that file in the object browser, note that in the sidebar the metadata includes the SSE encryption scheme and information on the key used to encrypt that object. This indicates the successful encrypted state of the object.

MinIO CLI

The following commands:

• Create a new alias <alias> for the MinIO deployment
• Create a new bucket for storing encrypted data
• Enable SSE-KMS encryption on that bucket

mc alias set local http://127.0.0.1:9000 ROOTUSER ROOTPASSWORD

mc mb local/encryptedbucket
mc encrypt set SSE-KMS encrypted-bucket-key ALIAS/encryptedbucket

Write a file to the bucket using mc cp or any S3-compatible SDK with a PutObject function. You can then run mc stat on the file to confirm the associated encryption metadata.

The network address and port the KES server listens to on startup. Defaults to port 7373 on all host network interfaces.

The identity for the KES superuser (root) identity. Clients connecting with a TLS certificate whose hash (kes identity of client.cert) matches this value have access to all KES API operations.

Specify disabled to remove the root identity and rely only on the policy configuration for controlling identity and access management to KES.

The TLS private key and certificate used by KES for establishing TLS-secured communications. Specify the full path for both the private .key and public .cert to the key and cert fields, respectively.

Specify one or more policies <kes/wiki/Configuration#policy-configuration> to control access to the KES server.

MinIO requires access to the following KES cryptographic APIs:

• /v1/key/create/*
• /v1/key/generate/*
• /v1/key/decrypt/*

Specifying additional keys does not expand MinIO functionality and may violate security best practices around providing unnecessary client access to cryptographic key operations.

You can restrict the range of key names MinIO can create as part of performing by specifying a prefix before the *. For example, minio-sse-* only grants access to create, generate, or decrypt keys using the minio-sse- prefix.

uses mTLS to authorize connecting clients by comparing the hash of the TLS certificate against the identities of each configured policy. Use the kes identity of command to compute the identity of the MinIO mTLS certificate and add it to the policy.<NAME>.identities array to associate MinIO to the <NAME> policy.

Specify an array of keys which must exist on the root KMS for to successfully start. KES attempts to create the keys if they do not exist and exits with an error if it fails to create any key. KES does not accept any client requests until it completes validation of all specified keys.

Important

The MinIO KES Play sandbox is public and grants root access to all created External Keys (EK). Any stored on the Play sandbox may be accessed or destroyed at any time, rendering protected data vulnerable or permanently unreadable.

• Never use the Play sandbox to protect data you cannot afford to lose or reveal.
• Never generate using names that reveal private, confidential, or internal naming conventions for your organization.
• Never use the Play sandbox for production environments.