distribution/docs/insecure.md
Novak Ivanovski e7dc768ae5 Self-signed certificate with Kubernetes fix
In Go 1.15 there is common name deprecation for using Common name:
https://golang.google.cn/doc/go1.15#commonname

This causes the self-signed cert to be rejected by some Kubernetes platforms:
https://stackoverflow.com/questions/64814173/how-do-i-use-sans-with-openssl-instead-of-common-name

Fix is to add this field to the cert.
2021-02-05 23:58:09 -05:00

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---
description: Deploying a Registry in an insecure fashion
keywords: registry, on-prem, images, tags, repository, distribution, insecure
title: Test an insecure registry
---
{% include registry.md %}
While it's highly recommended to secure your registry using a TLS certificate
issued by a known CA, you can choose to use self-signed certificates, or use
your registry over an unencrypted HTTP connection. Either of these choices
involves security trade-offs and additional configuration steps.
## Deploy a plain HTTP registry
> **Warning**:
> It's not possible to use an insecure registry with basic authentication.
{:.warning}
This procedure configures Docker to entirely disregard security for your
registry. This is **very** insecure and is not recommended. It exposes your
registry to trivial man-in-the-middle (MITM) attacks. Only use this solution for
isolated testing or in a tightly controlled, air-gapped environment.
1. Edit the `daemon.json` file, whose default location is
`/etc/docker/daemon.json` on Linux or
`C:\ProgramData\docker\config\daemon.json` on Windows Server. If you use
Docker Desktop for Mac or Docker Desktop for Windows, click the Docker icon, choose
**Preferences** (Mac) or **Settings** (Windows), and choose **Docker Engine**.
If the `daemon.json` file does not exist, create it. Assuming there are no
other settings in the file, it should have the following contents:
```json
{
"insecure-registries" : ["myregistrydomain.com:5000"]
}
```
Substitute the address of your insecure registry for the one in the example.
With insecure registries enabled, Docker goes through the following steps:
- First, try using HTTPS.
- If HTTPS is available but the certificate is invalid, ignore the error
about the certificate.
- If HTTPS is not available, fall back to HTTP.
2. Restart Docker for the changes to take effect.
Repeat these steps on every Engine host that wants to access your registry.
## Use self-signed certificates
> **Warning**:
> Using this along with basic authentication requires to **also** trust the certificate into the OS cert store for some versions of docker (see below)
{:.warning}
This is more secure than the insecure registry solution.
1. Generate your own certificate:
```bash
$ mkdir -p certs
$ openssl req \
-newkey rsa:4096 -nodes -sha256 -keyout certs/domain.key \
-addext "subjectAltName = DNS:myregistry.domain.com" \
-x509 -days 365 -out certs/domain.crt
```
Be sure to use the name `myregistrydomain.com` as a CN.
2. Use the result to [start your registry with TLS enabled](./deploying.md#get-a-certificate).
3. Instruct every Docker daemon to trust that certificate. The way to do this
depends on your OS.
- **Linux**: Copy the `domain.crt` file to
`/etc/docker/certs.d/myregistrydomain.com:5000/ca.crt` on every Docker
host. You do not need to restart Docker.
- **Windows Server**:
1. Open Windows Explorer, right-click the `domain.crt`
file, and choose Install certificate. When prompted, select the following
options:
| Store location | local machine |
| Place all certificates in the following store | selected |
2. Click **Browser** and select **Trusted Root Certificate Authorities**.
3. Click **Finish**. Restart Docker.
- **Docker Desktop for Mac**: Follow the instructions in
[Adding custom CA certificates](../docker-for-mac/index.md#add-tls-certificates){: target="_blank" rel="noopener" class="_"}.
Restart Docker.
- **Docker Desktop for Windows**: Follow the instructions in
[Adding custom CA certificates](../docker-for-windows/index.md#adding-tls-certificates){: target="_blank" rel="noopener" class="_"}.
Restart Docker.
## Troubleshoot insecure registry
This section lists some common failures and how to recover from them.
### Failing...
Failing to configure the Engine daemon and trying to pull from a registry that is not using
TLS results in the following message:
```none
FATA[0000] Error response from daemon: v1 ping attempt failed with error:
Get https://myregistrydomain.com:5000/v1/_ping: tls: oversized record received with length 20527.
If this private registry supports only HTTP or HTTPS with an unknown CA certificate, add
`--insecure-registry myregistrydomain.com:5000` to the daemon's arguments.
In the case of HTTPS, if you have access to the registry's CA certificate, no need for the flag;
simply place the CA certificate at /etc/docker/certs.d/myregistrydomain.com:5000/ca.crt
```
### Docker still complains about the certificate when using authentication?
When using authentication, some versions of Docker also require you to trust the
certificate at the OS level.
#### Ubuntu
```bash
$ cp certs/domain.crt /usr/local/share/ca-certificates/myregistrydomain.com.crt
update-ca-certificates
```
#### Red Hat Enterprise Linux
```bash
cp certs/domain.crt /etc/pki/ca-trust/source/anchors/myregistrydomain.com.crt
update-ca-trust
```
#### Oracle Linux
```bash
$ update-ca-trust enable
```
Restart Docker for the changes to take effect.
### Windows
Open Windows Explorer, right-click the certificate, and choose
**Install certificate**.
Then, select the following options:
* Store location: local machine
* Check **place all certificates in the following store**
* Click **Browser**, and select **Trusted Root Certificate Authorities**
* Click **Finish**
[Learn more about managing TLS certificates](https://technet.microsoft.com/en-us/library/cc754841(v=ws.11).aspx#BKMK_addlocal).
After adding the CA certificate to Windows, restart Docker Desktop for Windows.