Cloud Function 使用 KMS 密钥解密的权限被拒绝

Question

我有一个 Python 云函数，它使用 KMS 密钥来解密环境中其他服务的一些身份验证令牌，如https://dev.to/googlecloud/using-secrets-in-google-cloud-functions-5aem

每当我运行我的函数时，我都会收到 403 Permission Denied。 当我在计算机上本地调用该函数时，它工作正常。 我已经尝试将“Cloud KMS CryptoKey Decrypter”角色添加到默认的 Compute Engine 服务帐户，但没有奏效。

还有其他想法吗？

编辑：这里有一些代码显示了我在做什么。 环境变量存储在environment.yaml文件中，我在gcloud functions deploy时指向该文件

def decrypt_secret(key: str, secret: str):
    kms_client = kms.KeyManagementServiceClient()
    decrypted = kms_client.decrypt(key, base64.b64decode(secret))
    return decrypted.plaintext.decode("ascii")

def do_kms_stuff():
    key = os.environ["KMS_RESOURCE_NAME"]
    session = boto3.Session(
        profile_name="my-profile",
        aws_access_key_id=decrypt_secret(
            key, os.environ["AWS_ACCESS_KEY_ID_ENCRYPTED"]
        ),
        aws_secret_access_key=decrypt_secret(
            key, os.environ["AWS_SECRET_ACCESS_KEY_ENCRYPTED"]
        ),
    )
    # ...

这是来自 Cloud Functions 控制台的错误：

File "<string>", line 3, in raise_from: google.api_core.exceptions.PermissionDenied: 403 Permission 'cloudkms.cryptoKeyVersions.useToDecrypt' denied on resource 'projects/my-project/locations/my-location1/keyRings/my-keyring/cryptoKeys/my-key' (or it may not exist). at error_remapped_callable (/env/local/lib/python3.7/site-packages/google/api_core/grpc_helpers.py:59) at func_with_timeout (/env/local/lib/python3.7/site-packages/google/api_core/timeout.py:214) at retry_target (/env/local/lib/python3.7/site-packages/google/api_core/retry.py:182) at retry_wrapped_func (/env/local/lib/python3.7/site-packages/google/api_core/retry.py:277) at
__call__ (/env/local/lib/python3.7/site-packages/google/api_core/gapic_v1/method.py:143) at decrypt (/env/local/lib/python3.7/site-packages/google/cloud/kms_v1/gapic/key_management_service_client.py:1816) at decrypt_secret (/user_code/kms_stuff.py:17) at do_kms_stuff (/user_code/kms_stuff.py:48) at my_cloud_function (/user_code/main.py:46) at call_user_function (/env/local/lib/python3.7/site-packages/google/cloud/functions/worker.py:214) at invoke_user_function (/env/local/lib/python3.7/site-packages/google/cloud/functions/worker.py:217) at run_background_function (/env/local/lib/python3.7/site-packages/google/cloud/functions/worker.py:383)

Answer 1

正如@DazWilkin 和@pessolato 所提到的，问题是我使用了错误的服务帐户。 一旦我更改为使用默认的 AppSpot 帐户，一切都会顺利进行。