3b1e458374
Commit 77b8465d7e68ca102d7aae839c7b3fe0ecd28398 added a secret update
endpoint to allow updating labels on existing secrets. However, when
implementing the endpoint, the DebugRequestMiddleware was not updated
to scrub the Data field (as is being done when creating a secret).
When updating a secret (to set labels), the Data field should be either
`nil` (not set), or contain the same value as the existing secret. In
situations where the Data field is set, and the `dockerd` daemon is
running with debugging enabled / log-level debug, the base64-encoded
value of the secret is printed to the daemon logs.
The docker cli does not have a `docker secret update` command, but
when using `docker stack deploy`, the docker cli sends the secret
data both when _creating_ a stack, and when _updating_ a stack, thus
leaking the secret data if the daemon runs with debug enabled:
1. Start the daemon in debug-mode
dockerd --debug
2. Initialize swarm
docker swarm init
3. Create a file containing a secret
echo secret > my_secret.txt
4. Create a docker-compose file using that secret
cat > docker-compose.yml <<'EOF'
version: "3.3"
services:
web:
image: nginx:alpine
secrets:
- my_secret
secrets:
my_secret:
file: ./my_secret.txt
EOF
5. Deploy the stack
docker stack deploy -c docker-compose.yml test
6. Verify that the secret is scrubbed in the daemon logs
DEBU[2019-07-01T22:36:08.170617400Z] Calling POST /v1.30/secrets/create
DEBU[2019-07-01T22:36:08.171364900Z] form data: {"Data":"*****","Labels":{"com.docker.stack.namespace":"test"},"Name":"test_my_secret"}
7. Re-deploy the stack to trigger an "update"
docker stack deploy -c docker-compose.yml test
8. Notice that this time, the Data field is not scrubbed, and the base64-encoded secret is logged
DEBU[2019-07-01T22:37:35.828819400Z] Calling POST /v1.30/secrets/w3hgvwpzl8yooq5ctnyp71v52/update?version=34
DEBU[2019-07-01T22:37:35.829993700Z] form data: {"Data":"c2VjcmV0Cg==","Labels":{"com.docker.stack.namespace":"test"},"Name":"test_my_secret"}
This patch modifies `maskSecretKeys` to unconditionally scrub `Data` fields.
Currently, only the `secrets` and `configs` endpoints use a field with this
name, and no other POST API endpoints use a data field, so scrubbing this
field unconditionally will only scrub requests for those endpoints.
If a new endpoint is added in future where this field should not be scrubbed,
we can re-introduce more fine-grained (path-specific) handling.
This patch introduces some change in behavior:
- In addition to secrets, requests to create or update _configs_ will
now have their `Data` field scrubbed. Generally, the actual data should
not be interesting for debugging, so likely will not be problematic.
In addition, scrubbing this data for configs may actually be desirable,
because (even though they are not explicitely designed for this purpose)
configs may contain sensitive data (credentials inside a configuration
file, e.g.).
- Requests that send key/value pairs as a "map" and that contain a
key named "data", will see the value of that field scrubbed. This
means that (e.g.) setting a `label` named `data` on a config, will
scrub/mask the value of that label.
- Note that this is already the case for any label named `jointoken`,
`password`, `secret`, `signingcakey`, or `unlockkey`.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
(cherry picked from commit c7ce4be93ae8edd2da62a588e01c67313a4aba0c)
Signed-off-by: Tibor Vass <tibor@docker.com>
(cherry picked from commit 73db8c77bfb2d0cbdf71ce491f3d3e66c9dd5be6)
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Upstream-commit: 32b40c53662e733b4627b0b303c71b52484a31f4
Component: engine
Working on the Engine API
The Engine API is an HTTP API used by the command-line client to communicate with the daemon. It can also be used by third-party software to control the daemon.
It consists of various components in this repository:
api/swagger.yamlA Swagger definition of the API.api/types/Types shared by both the client and server, representing various objects, options, responses, etc. Most are written manually, but some are automatically generated from the Swagger definition. See #27919 for progress on this.cli/The command-line client.client/The Go client used by the command-line client. It can also be used by third-party Go programs.daemon/The daemon, which serves the API.
Swagger definition
The API is defined by the Swagger definition in api/swagger.yaml. This definition can be used to:
- Automatically generate documentation.
- Automatically generate the Go server and client. (A work-in-progress.)
- Provide a machine readable version of the API for introspecting what it can do, automatically generating clients for other languages, etc.
Updating the API documentation
The API documentation is generated entirely from api/swagger.yaml. If you make updates to the API, edit this file to represent the change in the documentation.
The file is split into two main sections:
definitions, which defines re-usable objects used in requests and responsespaths, which defines the API endpoints (and some inline objects which don't need to be reusable)
To make an edit, first look for the endpoint you want to edit under paths, then make the required edits. Endpoints may reference reusable objects with $ref, which can be found in the definitions section.
There is hopefully enough example material in the file for you to copy a similar pattern from elsewhere in the file (e.g. adding new fields or endpoints), but for the full reference, see the Swagger specification.
swagger.yaml is validated by hack/validate/swagger to ensure it is a valid Swagger definition. This is useful when making edits to ensure you are doing the right thing.
Viewing the API documentation
When you make edits to swagger.yaml, you may want to check the generated API documentation to ensure it renders correctly.
Run make swagger-docs and a preview will be running at http://localhost. Some of the styling may be incorrect, but you'll be able to ensure that it is generating the correct documentation.
The production documentation is generated by vendoring swagger.yaml into docker/docker.github.io.