SAML

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Chef Automate can integrate with existing Security Assertion Markup Language (SAML) services to authenticate users in Chef Automate, and use their existing group memberships to determine their Chef Automate permissions.

Authentication via Existing Identity Management Systems

Chef Automate supports externally managed users from an external identity provider (IdP) as well as local users. You can configure one LDAP service (or MSAD for simplified configuration of Active Directory setups) and one SAML IdP on the same instance.

If you are only using local users and teams that you create in Chef Automate, then you do not need to configure an external IdP. See the Users documentation for information on creating and managing local users.

Configure Identity Providers

To configure authentication for your Chef Automate installation:

1. Create a TOML file with your partial SAML configuration.
2. Run chef-automate config patch </path/to/your-file.toml> on the command line to apply your change.

Change Identity Providers

To change your configured IdP, replace your existing configuration with these steps:

1. Run chef-automate config show config.toml.
2. Edit config.toml to replace the dex.v1.sys.connectors section with the config values for your new identity provider.
3. Run chef-automate config set config.toml to set your updated config.

Supported Identity Management Systems

• Azure AD
• Office365
• OKTA
• OneLogin
• Ping
• Tivoli Federated Identity Manager

Chef Automate uses the Dex library to support SAML integrations. Dex does not support IdP-initiated SAML logins with for these IdPs. This means that Chef Automate also cannot support IdP-initiated SAML logins with these IdPs.

Attempting to sign in with an unsupported IdP-supported SAML login causes the unsupported auth mode error. Fall back to the typical SP-initiated login mode and proceed with your Chef Automate SAML configuration.

Azure Active Directory

Using Azure AD as an SAML IdP requires specific configuration for both Azure AD and Chef Automate.

In Azure AD, add Chef Automate as a non-gallery application, and then configure its SAML sign-in method. The Azure AD documentation provides a detailed guide. Enter https://automate.example.com/dex/callback as the value for both Identifier (Entity ID) and Reply URL (Assertion Consumer Service URL).

You may use the default claims provided by Azure AD. Remember to edit the Chef Automate configuration in config.toml to reflect this claims information.

Download the Certificate (Base64) in Azure AD and take note of the Login URL of use in the Chef Automate configuration.

After configuring Azure AD, edit your Chef Automate config.toml configuration file to reflect the values entered in the Azure AD interface.

The minimal configuration snippet in config.toml will looks like:

[dex.v1.sys.connectors.saml]
ca_contents="""
<<Certificate (Base64)>>
"""
sso_url = "<<Login URL>>"
email_attr = "http://schemas.xmlsoap.org/ws/2005/05/identity/claims/emailaddress"
username_attr = "http://schemas.xmlsoap.org/ws/2005/05/identity/claims/emailaddress"
entity_issuer = "https://automate.example.com/dex/callback"

where:

• ca_contents contains the value of the Certificate (Base64), and includes the -----BEGIN CERTIFICATE----- and -----END CERTIFICATE----- markers
• sso_url contains the value of Login URL
• entity_issuer contains the value of Identifier (Entity ID)

See the SAML Configuration Settings for further configuration options.

SAML Configuration Settings

The SAML configuration settings are:

[dex.v1.sys.connectors.saml]
ca_contents = "<your ca contents>"          # required
sso_url = "<your SSO URL>"                  # required
email_attr = "<your email attribute>"       # required
username_attr = "<your username attribute>" # required
groups_attr = "<your groups attribute>"     # optional
allowed_groups = ["group1", "group 2"]      # optional
entity_issuer = "<your entity issuer>"      # optional
name_id_policy_format = "<see below>"       # optional

ca_contents must contain a copy of the certificate used to sign the SAML assertions. The certificate should be a PEM-encoded string. For example,

ca_contents = """-----BEGIN CERTIFICATE-----
MIIE+DCCAuCgAwIBAgIBATANBgkqhkiG9w0BAQsFADAcMRowGAYDVQQDExFDaGVm
[...]
s1V9oZ7+NcK8vtcdXhjB5N65LbPlaT3nbvXGIvsQmoGc+FQ5WI4agoNlofOCogdW
k2WFcoiiKyeIznNScx/K6AeykKR/lPrJedanSA==
-----END CERTIFICATE-----
"""

Setting allowed_groups provides SAML sign-in for members of the listed groups and discards all user groups that are not in the list. Groups must be on the allowed_groups list to access Chef Automate.

For example, in the configuration example above, the users that belong to “group1” or “group2” may sign in to Chef Automate, and those groups would appear as team:saml:group1 and team:saml:group2, respectively. Members of the unlisted “group 3” would not have access to Chef Automate.

Chef Automate supports using SAML to authenticate users and apply permissions to SAML groups. See IAM Overview.

Member expressions are required for externally managed users and teams, as well as API tokens. See IAM_v2_Guide.

[dex.v1.sys.connectors.saml]
  ca_contents = "<your ca contents>"
  sso_url = "<your SAML SSO URL>"

  ###
  # SAML Attributes to map to a user's Chef Automate session
  ###
  # Example: "email"
  email_attr = "<your email attribute>"
  # Example: "name"
  username_attr = "<your username attribute>"
  # Example: "groups"
  groups_attr = "<your groups attribute>"

  # Optional: Manually specify Chef Automate's Issuer value.
  #
  # When provided Chef Automate will include this as the Issuer value in the SAML
  # AuthnRequest. It will also override the redirectURI as the required audience
  # when evaluating AudienceRestriction elements in the response.
  # Example: "https://automate.example.com/dex/callback"
  entity_issuer = "<your entity issuer>"

  # Optional: Specify the NameIDPolicy to use
  #
  # When provided, Chef Automate will request a name ID of the configured format
  # in the SAML AuthnRequest.
  # Defaults to "urn:oasis:names:tc:SAML:2.0:nameid-format:persistent".
  #
  # Note: Even when configured otherwise, the username gathered from the SAML
  # response is _treated_ as persistent. So, if this is set to
  #    "urn:oasis:names:tc:SAML:1.1:nameid-format:emailAddress"
  # and a user has changed their email address, they will be a _new_ user to Chef
  # Automate.
  name_id_policy_format = "urn:oasis:names:tc:SAML:1.1:nameid-format:unspecified"

In your SAML Identity Provider (IdP), your Chef Automate instance needs to be referenced as a Service Provider (SP). To do so, use https://automate.example.com/dex/callback. The concrete configuration items differ between IdP products, but it is often something like “Assertion Consumption URI” or “Single sign on URL”. For “Audience URI” or “SP Entity ID”, use the same address.

These values are accepted for name_id_policy_format:

• urn:oasis:names:tc:SAML:1.1:nameid-format:emailAddress
• urn:oasis:names:tc:SAML:1.1:nameid-format:unspecified
• urn:oasis:names:tc:SAML:1.1:nameid-format:X509SubjectName
• urn:oasis:names:tc:SAML:1.1:nameid-format:WindowsDomainQualifiedName
• urn:oasis:names:tc:SAML:2.0:nameid-format:encrypted
• urn:oasis:names:tc:SAML:2.0:nameid-format:entity
• urn:oasis:names:tc:SAML:2.0:nameid-format:kerberos
• urn:oasis:names:tc:SAML:2.0:nameid-format:persistent
• urn:oasis:names:tc:SAML:2.0:nameid-format:transient

Troubleshooting

Error: Unsupported auth mode

Attempting to sign in with an unsupported IdP-supported SAML login causes the unsupported auth mode error.

To remedy this error, fall back to the standard SP-initiated login mode.

Chef Automate uses the Dex library to support SAML integrations. Dex does not support IdP-initiated SAML logins with of these IdPs. This means that Chef Automate also cannot support IdP-initiated SAML logins with the IdPs:

• Azure AD
• Office365
• OKTA
• OneLogin
• Ping
• Tivoli Federated Identity Manager