From 6b4a26e23c60d06354cd5e9b8d200a31ccc9ec17 Mon Sep 17 00:00:00 2001 From: Ricardo Pardini Date: Tue, 6 Oct 2020 11:16:03 +0200 Subject: [PATCH] README: reword, one less header level --- README.md | 38 ++++++++++++++++++-------------------- 1 file changed, 18 insertions(+), 20 deletions(-) diff --git a/README.md b/README.md index fe9a88f..d024d91 100644 --- a/README.md +++ b/README.md @@ -1,10 +1,8 @@ -## docker-registry-proxy - -### TL,DR +## TL,DR A caching proxy for Docker; allows centralised management of (multiple) registries and their authentication; caches images from *any* registry. -### What? +## What? Essentially, it's a [man in the middle](https://en.wikipedia.org/wiki/Man-in-the-middle_attack): an intercepting proxy based on `nginx`, to which all docker traffic is directed using the `HTTPS_PROXY` mechanism and injected CA root certificates. @@ -15,25 +13,25 @@ As a bonus it allows for centralized management of Docker registry credentials, You configure the Docker clients (_err... Kubernetes Nodes?_) once, and then all configuration is done on the proxy -- for this to work it requires inserting a root CA certificate into system trusted root certs. -### master is unstable/beta +## master is unstable/beta - `master` (and `:latest` Docker tag) is unstable - Currently, stable version is `0.3.0`, see [0.3.0 tag on Github](https://github.com/rpardini/docker-registry-proxy/tree/0.3.0) -### Usage +## Usage - Run the proxy on a host close (network-wise: high bandwidth, same-VPC, etc) to the Docker clients - Expose port 3128 to the network - Map volume `/docker_mirror_cache` for up to `CACHE_MAX_SIZE` (32gb by default) of cached images across all cached registries - Map volume `/ca`, the proxy will store the CA certificate here across restarts. **Important** this is security sensitive. - Env `CACHE_MAX_SIZE` (default `32g`): set the max size to be used for caching local Docker image layers. Use [Nginx sizes](http://nginx.org/en/docs/syntax.html). -- Env `REGISTRIES`: space separated list of registries to cache; no need to include Docker Hub, its already there. +- Env `REGISTRIES`: space separated list of registries to cache; no need to include DockerHub, its already done internally. - Env `AUTH_REGISTRIES`: space separated list of `hostname:username:password` authentication info. - `hostname`s listed here should be listed in the REGISTRIES environment as well, so they can be intercepted. - Env `AUTH_REGISTRIES_DELIMITER` to change the separator between authentication info. By default, a space: "` `". If you use keys that contain spaces (as with Google Cloud Registry), you should update this variable, e.g. setting it to `AUTH_REGISTRIES_DELIMITER=";;;"`. In that case, `AUTH_REGISTRIES` could contain something like `registry1.com:user1:pass1;;;registry2.com:user2:pass2`. - Env `AUTH_REGISTRY_DELIMITER` to change the separator between authentication info *parts*. By default, a colon: "`:`". If you use keys that contain single colons, you should update this variable, e.g. setting it to `AUTH_REGISTRIES_DELIMITER=":::"`. In that case, `AUTH_REGISTRIES` could contain something like `registry1.com:::user1:::pass1 registry2.com:::user2:::pass2`. -#### DockerHub specifics +### DockerHub For Docker Hub authentication: - `hostname` should be `auth.docker.io` @@ -49,7 +47,7 @@ docker run --rm --name docker_registry_proxy -it \ rpardini/docker-registry-proxy:0.3.0 ``` -#### Simple registries (HTTP Basic auth) +### Simple registries (HTTP Basic auth) For regular registry auth (HTTP Basic), the `hostname` should be the registry itself... unless your registry uses a different auth server. @@ -57,7 +55,7 @@ See the example above for DockerHub, adapt the `your.own.registry` parts (in bot This should work for quay.io also, but I have no way to test. -#### GitLab specifics +### GitLab GitLab may use a different/separate domain to handle the authentication procedure. @@ -77,7 +75,7 @@ docker run --rm --name docker_registry_proxy -it \ rpardini/docker-registry-proxy:0.3.0 ``` -#### Google Container Registry (GCR) specifics +### Google Container Registry (GCR) For Google Container Registry (GCR), username should be `_json_key` and the password should be the contents of the service account JSON. Check out [GCR docs](https://cloud.google.com/container-registry/docs/advanced-authentication#json_key_file). @@ -100,7 +98,7 @@ docker run --rm --name docker_registry_proxy -it \ rpardini/docker-registry-proxy:0.3.0 ``` -### Configuring the Docker clients / Kubernetes nodes +## Configuring the Docker clients / Kubernetes nodes Let's say you setup the proxy on host `192.168.66.72`, you can then `curl http://192.168.66.72:3128/ca.crt` and get the proxy CA certificate. @@ -133,7 +131,7 @@ systemctl daemon-reload systemctl restart docker.service ``` -### Testing +## Testing Clear `dockerd` of everything not currently running: `docker system prune -a -f` *beware* @@ -145,7 +143,7 @@ Do the same for `docker pull ubuntu` and rejoice. Test your own registry caching and authentication the same way; you don't need `docker login`, or `.docker/config.json` anymore. -### Gotchas +## Gotchas - If you authenticate to a private registry and pull through the proxy, those images will be served to any client that can reach the proxy, even without authentication. *beware* - Repeat, **this will make your private images very public if you're not careful**. @@ -154,7 +152,7 @@ Test your own registry caching and authentication the same way; you don't need ` - On Mac and Windows the CA-certificate part will be very different but should work in principle. - Please send PRs with instructions for Windows and Mac if you succeed! -#### Why not use Docker's own registry, which has a mirror feature? +### Why not use Docker's own registry, which has a mirror feature? Yes, Docker offers [Registry as a pull through cache](https://docs.docker.com/registry/recipes/mirror/), *unfortunately* it only covers the DockerHub case. It won't cache images from `quay.io`, `k8s.gcr.io`, `gcr.io`, or any such, including any private registries. @@ -167,14 +165,14 @@ with no repository reference (eg, from DockerHub). When a repository is specified `dockerd` goes directly there, via HTTPS (and also via HTTP if included in a `--insecure-registry` list), thus completely ignoring the configured mirror. -#### Docker itself should provide this. +### Docker itself should provide this. Yeah. Docker Inc should do it. So should NPM, Inc. Wonder why they don't. 😼 ### TODO: -- Allow using multiple credentials for DockerHub; this is possible since the `/token` request includes the wanted repo as a query string parameter. -- Test and make auth work with quay.io, unfortunately I don't have access to it (_hint, hint, quay_) -- Hide the mitmproxy building code under a Docker build ARG. [DONE] -- I hope that in the future this can also be used as a "Developer Office" proxy, where many developers on a fast local network +- [ ] Allow using multiple credentials for DockerHub; this is possible since the `/token` request includes the wanted repo as a query string parameter. +- [ ] Test and make auth work with quay.io, unfortunately I don't have access to it (_hint, hint, quay_) +- [x] Hide the mitmproxy building code under a Docker build ARG. +- [ ] hope that in the future this can also be used as a "Developer Office" proxy, where many developers on a fast local network share a proxy for bandwidth and speed savings; work is ongoing in this direction.