Certmagic Storage Backend for Google Cloud Storage

This library allows you to use Google Cloud Storage as key/certificate storage backend for your Certmagic-enabled HTTPS server. To protect your keys from unwanted attention, client-side encryption is possible.

Usage

In this section, we create an caddy confi using our GCS storage.

Getting started

1. Create a Caddyfile

{
	storage gcs {
    bucket some-bucket
  }
}
localhost
acme_server
respond "Hello Caddy Storage GCS!"

2. Start GCS emulator

docker run -d \
  -p 9023:9023 \
  --name gcp-storage-emulator \
  oittaa/gcp-storage-emulator \
  start --default-bucket=some-bucket --port 9023 --in-memory


export STORAGE_EMULATOR_HOST=http://localhost:9023

3. Start caddy

xcaddy run

4. Check that it works

open https://localhost

Client Side Encryption

This module supports client side encryption using google Tink, thus providing a simple way to customize the encryption algorithm and handle key rotation. To get started:

1. Install tinkey

2. Create a key set

  tinkey create-keyset --key-template AES128_GCM_RAW --out keyset.json

Here is an example keyset.json

{
  "primaryKeyId": 1818673287,
  "key": [
    {
      "keyData": {
        "typeUrl": "type.googleapis.com/google.crypto.tink.AesGcmKey",
        "value": "GhDEQ/4v72esAv3rbwZyS+ls",
        "keyMaterialType": "SYMMETRIC"
      },
      "status": "ENABLED",
      "keyId": 1818673287,
      "outputPrefixType": "RAW"
    }
  ]
}

3. Start caddy with the following config

{
  storage gcs {
    bucket-name some-bucket
    encryption-key-set ./keyset.json
  }
}
localhost
acme_server
respond "Hello Caddy Storage GCS!"

# restart the fake gcs backend to start with an empty bucket
docker restart gcp-storage-emulator

# start caddy
xcaddy run

# to rotate the key-set
tinkey rotate-keyset --in keyset.json  --key-template AES128_GCM_RAW