mirror of
https://github.com/moby/moby.git
synced 2022-11-09 12:21:53 -05:00
7df5493071
This commit contains a re-structured re-write of the original
certificated.md file, containing the amendments proposed with
PR #7120 (commit ID bd28595e31) by @timthelion.
Related to: https://github.com/dotcloud/docker/pull/7120
2014-07-30: Update/rebase/squash based on the comments from @jamtur01 and @fredlf.
2014-08-12: Update/rebase/squash based on the comments from @fredlf (of 2014-08-12).
Docker-DCO-1.1-Signed-off-by: O.S. Tezer <ostezer@gmail.com> (github: ostezer)
114 lines
4.3 KiB
Markdown
114 lines
4.3 KiB
Markdown
page_title: Using certificates for repository client verification
|
|
page_description: How to set up and use certificates with a registry to verify access
|
|
page_keywords: Usage, registry, repository, client, root, certificate, docker, apache, ssl, tls, documentation, examples, articles, tutorials
|
|
|
|
# Using certificates for repository client verification
|
|
|
|
In [Running Docker with HTTPS](/articles/https), you learned that, by default,
|
|
Docker runs via a non-networked Unix socket and TLS must be enabled in order
|
|
to have the Docker client and the daemon communicate securely over HTTPS.
|
|
|
|
Now, you will see how to allow the Docker registry (i.e., *a server*) to
|
|
verify that the Docker daemon (i.e., *a client*) has the right to access the
|
|
images being hosted with *certificate-based client-server authentication*.
|
|
|
|
We will show you how to install a Certificate Authority (CA) root certificate
|
|
for the registry and how to set the client TLS certificate for verification.
|
|
|
|
## Understanding the configuration
|
|
|
|
A custom certificate is configured by creating a directory under
|
|
`/etc/docker/certs.d` using the same name as the registry's hostname (e.g.,
|
|
`localhost`). All `*.crt` files are added to this directory as CA roots.
|
|
|
|
> **Note:**
|
|
> In the absence of any root certificate authorities, Docker
|
|
> will use the system default (i.e., host's root CA set).
|
|
|
|
The presence of one or more `<filename>.key/cert` pairs indicates to Docker
|
|
that there are custom certificates required for access to the desired
|
|
repository.
|
|
|
|
> **Note:**
|
|
> If there are multiple certificates, each will be tried in alphabetical
|
|
> order. If there is an authentication error (e.g., 403, 5xx, etc.), Docker
|
|
> will continue to try with the next certificate.
|
|
|
|
Our example is set up like this:
|
|
|
|
/etc/docker/certs.d/ <-- Certificate directory
|
|
└── localhost <-- Hostname
|
|
├── client.cert <-- Client certificate
|
|
├── client.key <-- Client key
|
|
└── localhost.crt <-- Registry certificate
|
|
|
|
## Creating the client certificates
|
|
|
|
You will use OpenSSL's `genrsa` and `req` commands to first generate an RSA
|
|
key and then use the key to create the certificate request.
|
|
|
|
$ openssl genrsa -out client.key 1024
|
|
$ openssl req -new -x509 -text -key client.key -out client.cert
|
|
|
|
> **Warning:**:
|
|
> Using TLS and managing a CA is an advanced topic.
|
|
> You should be familiar with OpenSSL, x509, and TLS before
|
|
> attempting to use them in production.
|
|
|
|
> **Warning:**
|
|
> These TLS commands will only generate a working set of certificates on Linux.
|
|
> The version of OpenSSL in Mac OS X is incompatible with the type of
|
|
> certificate Docker requires.
|
|
|
|
## Testing the verification setup
|
|
|
|
You can test this setup by using Apache to host a Docker registry.
|
|
For this purpose, you can copy a registry tree (containing images) inside
|
|
the Apache root.
|
|
|
|
> **Note:**
|
|
> You can find such an example [here](
|
|
> http://people.gnome.org/~alexl/v1.tar.gz) - which contains the busybox image.
|
|
|
|
Once you set up the registry, you can use the following Apache configuration
|
|
to implement certificate-based protection.
|
|
|
|
# This must be in the root context, otherwise it causes a re-negotiation
|
|
# which is not supported by the TLS implementation in go
|
|
SSLVerifyClient optional_no_ca
|
|
|
|
<Location /v1>
|
|
Action cert-protected /cgi-bin/cert.cgi
|
|
SetHandler cert-protected
|
|
|
|
Header set x-docker-registry-version "0.6.2"
|
|
SetEnvIf Host (.*) custom_host=$1
|
|
Header set X-Docker-Endpoints "%{custom_host}e"
|
|
</Location>
|
|
|
|
Save the above content as `/etc/httpd/conf.d/registry.conf`, and
|
|
continue with creating a `cert.cgi` file under `/var/www/cgi-bin/`.
|
|
|
|
#!/bin/bash
|
|
if [ "$HTTPS" != "on" ]; then
|
|
echo "Status: 403 Not using SSL"
|
|
echo "x-docker-registry-version: 0.6.2"
|
|
echo
|
|
exit 0
|
|
fi
|
|
if [ "$SSL_CLIENT_VERIFY" == "NONE" ]; then
|
|
echo "Status: 403 Client certificate invalid"
|
|
echo "x-docker-registry-version: 0.6.2"
|
|
echo
|
|
exit 0
|
|
fi
|
|
echo "Content-length: $(stat --printf='%s' $PATH_TRANSLATED)"
|
|
echo "x-docker-registry-version: 0.6.2"
|
|
echo "X-Docker-Endpoints: $SERVER_NAME"
|
|
echo "X-Docker-Size: 0"
|
|
echo
|
|
|
|
cat $PATH_TRANSLATED
|
|
|
|
This CGI script will ensure that all requests to `/v1` *without* a valid
|
|
certificate will be returned with a `403` (i.e., HTTP forbidden) error.
|