debian-mirror-gitlab/doc/administration/auth/smartcard.md
2020-08-09 17:41:57 +05:30

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---
type: reference
---
# Smartcard authentication **(PREMIUM ONLY)**
GitLab supports authentication using smartcards.
## Existing password authentication
> [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/33669) in GitLab 12.6.
By default, existing users can continue to log in with a username and password when smartcard
authentication is enabled.
To force existing users to use only smartcard authentication,
[disable username and password authentication](../../user/admin_area/settings/sign_in_restrictions.md#password-authentication-enabled).
## Authentication methods
GitLab supports two authentication methods:
- X.509 certificates with local databases.
- LDAP servers.
### Authentication against a local database with X.509 certificates
> [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/726) in [GitLab Premium](https://about.gitlab.com/pricing/) 11.6 as an experimental feature.
CAUTION: **Caution:**
Smartcard authentication against local databases may change or be removed completely in future
releases.
Smartcards with X.509 certificates can be used to authenticate with GitLab.
To use a smartcard with an X.509 certificate to authenticate against a local
database with GitLab, `CN` and `emailAddress` must be defined in the
certificate. For example:
```plaintext
Certificate:
Data:
Version: 1 (0x0)
Serial Number: 12856475246677808609 (0xb26b601ecdd555e1)
Signature Algorithm: sha256WithRSAEncryption
Issuer: O=Random Corp Ltd, CN=Random Corp
Validity
Not Before: Oct 30 12:00:00 2018 GMT
Not After : Oct 30 12:00:00 2019 GMT
Subject: CN=Gitlab User, emailAddress=gitlab-user@example.com
```
### Authentication against a local database with X.509 certificates and SAN extension
> [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/8605) in [GitLab Premium](https://about.gitlab.com/pricing/) 12.3.
Smartcards with X.509 certificates using SAN extensions can be used to authenticate
with GitLab.
NOTE: **Note:**
This is an experimental feature. Smartcard authentication against local databases may
change or be removed completely in future releases.
To use a smartcard with an X.509 certificate to authenticate against a local
database with GitLab, in:
- GitLab 12.4 and later, at least one of the `subjectAltName` (SAN) extensions
need to define the user identity (`email`) within the GitLab instance (`URI`).
`URI`: needs to match `Gitlab.config.host.gitlab`.
- From [GitLab 12.5](https://gitlab.com/gitlab-org/gitlab/-/issues/33907),
if your certificate contains only **one** SAN email entry, you don't need to
add or modify it to match the `email` with the `URI`.
For example:
```plaintext
Certificate:
Data:
Version: 1 (0x0)
Serial Number: 12856475246677808609 (0xb26b601ecdd555e1)
Signature Algorithm: sha256WithRSAEncryption
Issuer: O=Random Corp Ltd, CN=Random Corp
Validity
Not Before: Oct 30 12:00:00 2018 GMT
Not After : Oct 30 12:00:00 2019 GMT
...
X509v3 extensions:
X509v3 Key Usage:
Key Encipherment, Data Encipherment
X509v3 Extended Key Usage:
TLS Web Server Authentication
X509v3 Subject Alternative Name:
email:gitlab-user@example.com, URI:http://gitlab.example.com/
```
### Authentication against an LDAP server
> [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/7693) in [GitLab Premium](https://about.gitlab.com/pricing/) 11.8 as an experimental feature. Smartcard authentication against an LDAP server may change or be removed completely in future releases.
GitLab implements a standard way of certificate matching following
[RFC4523](https://tools.ietf.org/html/rfc4523). It uses the
`certificateExactMatch` certificate matching rule against the `userCertificate`
attribute. As a prerequisite, you must use an LDAP server that:
- Supports the `certificateExactMatch` matching rule.
- Has the certificate stored in the `userCertificate` attribute.
## Configure GitLab for smartcard authentication
**For Omnibus installations**
1. Edit `/etc/gitlab/gitlab.rb`:
```ruby
gitlab_rails['smartcard_enabled'] = true
gitlab_rails['smartcard_ca_file'] = "/etc/ssl/certs/CA.pem"
gitlab_rails['smartcard_client_certificate_required_port'] = 3444
```
1. Save the file and [reconfigure](../restart_gitlab.md#omnibus-gitlab-reconfigure)
GitLab for the changes to take effect.
---
**For installations from source**
1. Configure NGINX to request a client side certificate
In NGINX configuration, an **additional** server context must be defined with
the same configuration except:
- The additional NGINX server context must be configured to run on a different
port:
```plaintext
listen *:3444 ssl;
```
- It can also be configured to run on a different hostname:
```plaintext
listen smartcard.example.com:443 ssl;
```
- The additional NGINX server context must be configured to require the client
side certificate:
```plaintext
ssl_verify_depth 2;
ssl_client_certificate /etc/ssl/certs/CA.pem;
ssl_verify_client on;
```
- The additional NGINX server context must be configured to forward the client
side certificate:
```plaintext
proxy_set_header X-SSL-Client-Certificate $ssl_client_escaped_cert;
```
For example, the following is an example server context in an NGINX
configuration file (such as in `/etc/nginx/sites-available/gitlab-ssl`):
```plaintext
server {
listen smartcard.example.com:3443 ssl;
# certificate for configuring SSL
ssl_certificate /path/to/example.com.crt;
ssl_certificate_key /path/to/example.com.key;
ssl_verify_depth 2;
# CA certificate for client side certificate verification
ssl_client_certificate /etc/ssl/certs/CA.pem;
ssl_verify_client on;
location / {
proxy_set_header Host $http_host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header X-Forwarded-Proto $scheme;
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection $connection_upgrade;
proxy_set_header X-SSL-Client-Certificate $ssl_client_escaped_cert;
proxy_read_timeout 300;
proxy_pass http://gitlab-workhorse;
}
}
```
1. Edit `config/gitlab.yml`:
```yaml
## Smartcard authentication settings
smartcard:
# Allow smartcard authentication
enabled: true
# Path to a file containing a CA certificate
ca_file: '/etc/ssl/certs/CA.pem'
# Host and port where the client side certificate is requested by the
# webserver (NGINX/Apache)
client_certificate_required_host: smartcard.example.com
client_certificate_required_port: 3443
```
NOTE: **Note:**
Assign a value to at least one of the following variables:
`client_certificate_required_host` or `client_certificate_required_port`.
1. Save the file and [restart](../restart_gitlab.md#installations-from-source)
GitLab for the changes to take effect.
### Additional steps when using SAN extensions
**For Omnibus installations**
1. Add to `/etc/gitlab/gitlab.rb`:
```ruby
gitlab_rails['smartcard_san_extensions'] = true
```
1. Save the file and [reconfigure](../restart_gitlab.md#omnibus-gitlab-reconfigure)
GitLab for the changes to take effect.
**For installations from source**
1. Add the `san_extensions` line to `config/gitlab.yml` within the smartcard section:
```yaml
smartcard:
enabled: true
ca_file: '/etc/ssl/certs/CA.pem'
client_certificate_required_port: 3444
# Enable the use of SAN extensions to match users with certificates
san_extensions: true
```
1. Save the file and [restart](../restart_gitlab.md#installations-from-source)
GitLab for the changes to take effect.
### Additional steps when authenticating against an LDAP server
**For Omnibus installations**
1. Edit `/etc/gitlab/gitlab.rb`:
```ruby
gitlab_rails['ldap_servers'] = YAML.load <<-EOS
main:
# snip...
# Enable smartcard authentication against the LDAP server. Valid values
# are "false", "optional", and "required".
smartcard_auth: optional
EOS
```
1. Save the file and [reconfigure](../restart_gitlab.md#omnibus-gitlab-reconfigure)
GitLab for the changes to take effect.
**For installations from source**
1. Edit `config/gitlab.yml`:
```yaml
production:
ldap:
servers:
main:
# snip...
# Enable smartcard authentication against the LDAP server. Valid values
# are "false", "optional", and "required".
smartcard_auth: optional
```
1. Save the file and [restart](../restart_gitlab.md#installations-from-source)
GitLab for the changes to take effect.
### Require browser session with smartcard sign-in for Git access
**For Omnibus installations**
1. Edit `/etc/gitlab/gitlab.rb`:
```ruby
gitlab_rails['smartcard_required_for_git_access'] = true
```
1. Save the file and [reconfigure](../restart_gitlab.md#omnibus-gitlab-reconfigure)
GitLab for the changes to take effect.
**For installations from source**
1. Edit `config/gitlab.yml`:
```yaml
## Smartcard authentication settings
smartcard:
# snip...
# Browser session with smartcard sign-in is required for Git access
required_for_git_access: true
```
1. Save the file and [restart](../restart_gitlab.md#installations-from-source)
GitLab for the changes to take effect.
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