SAML 構成リファレンス

About SAML configuration

To use SAML single sign-on (SSO) for authentication to GitHub Enterprise Cloud, you must configure both your external SAML identity provider (IdP) and your enterprise or organization on GitHub. In a SAML configuration, GitHub Enterprise Cloud functions as a SAML service provider (SP). For more information about authentication for your enterprise, see About identity and access management.

GitHub Enterprise Cloud provides integration according to the SAML 2.0 specification. For more information, see the SAML Wiki on the OASIS website.

You must enter unique values from your SAML IdP when configuring SAML SSO for GitHub Enterprise Cloud, and you must also enter unique values from GitHub Enterprise Cloud on your IdP.

SAML metadata

The SP metadata for GitHub Enterprise Cloud is available for either organizations or enterprises with SAML SSO. GitHub Enterprise Cloud uses the urn:oasis:names:tc:SAML:2.0:bindings:HTTP-POST binding.

If you use Enterprise Managed Users, you can only enable SAML SSO at the enterprise level.

Organizations

You can configure SAML SSO for an individual organization in your enterprise. You can also configure SAML SSO for an organization if you use an individual organization on GitHub Enterprise Cloud and do not use an enterprise account. For more information, see Managing SAML single sign-on for your organization.

The SP metadata for an organization on GitHub is available at https://github.com/orgs/ORGANIZATION/saml/metadata, where ORGANIZATION is the name of your organization on GitHub.

Value	Other names	Description	Example
SP Entity ID	SP URL, audience restriction	The top-level URL for your organization on GitHub.com	https://github.com/orgs/ORGANIZATION
SP Assertion Consumer Service (ACS) URL	Reply, recipient, or destination URL	URL where IdP sends SAML responses	https://github.com/orgs/ORGANIZATION/saml/consume
SP Single Sign-On (SSO) URL		URL where IdP begins SSO	https://github.com/orgs/ORGANIZATION/sso

Enterprises

Depending on your environment, the SP metadata for an enterprise on GitHub Enterprise Cloud is available at either:

• https://github.com/enterprises/ENTERPRISE/saml/metadata, where ENTERPRISE is the name of your enterprise
• https://SUBDOMAIN.ghe.com/enterprises/SUBDOMAIN/saml/metadata, where SUBDOMAIN is the subdomain for your enterprise

Value	Other names	Description	Example
SP Entity ID	SP URL, audience restriction	The top-level URL for your enterprise on GitHub.com	https://github.com/enterprises/ENTERPRISE
SP Assertion Consumer Service (ACS) URL	Reply, recipient, or destination URL	URL where IdP sends SAML responses	https://github.com/enterprises/ENTERPRISE/saml/consume
SP Single Sign-On (SSO) URL		URL where IdP begins SSO	https://github.com/enterprises/ENTERPRISE/saml/sso

SAML attributes

The following SAML attributes are available for GitHub Enterprise Cloud.

Name	Required	Description
NameID		A persistent user identifier. Any persistent name identifier format may be used. If you use an enterprise with Enterprise Managed Users, GitHub Enterprise Cloud will normalize the NameID element to use as a username unless one of the alternative assertions is provided. For more information, see Username considerations for external authentication. > [!NOTE] It's important to use a human-readable, persistent identifier. Using a transient identifier format like urn:oasis:names:tc:SAML:2.0:nameid-format:transient will result in re-linking of accounts on every sign-in, which can be detrimental to authorization management.
SessionNotOnOrAfter		The date that GitHub Enterprise Cloud invalidates the associated session. After invalidation, the person must authenticate once again to access your enterprise's resources. For more information, see Session duration and timeout.
full_name		If you configure SAML SSO for an enterprise and you use Enterprise Managed Users, the full name of the user to display on the user's profile page.
emails		The email addresses for the user. If you sync license usage between GitHub Enterprise Server and GitHub Enterprise Cloud, GitHub Connect uses emails to identify unique users across products. For more information, see Syncing license usage between GitHub Enterprise Server and GitHub Enterprise Cloud.
public_keys		If you configure SAML SSO for an enterprise and you use Enterprise Managed Users, the public SSH keys for the user. You can specify more than one key.
gpg_keys		If you configure SAML SSO for an enterprise and you use Enterprise Managed Users, the GPG keys for the user. You can specify more than one key.

To specify more than one value for an attribute, use multiple <saml2:AttributeValue> elements.

<saml2:Attribute FriendlyName="public_keys" Name="urn:oid:1.2.840.113549.1.1.1" NameFormat="urn:oasis:names:tc:SAML:2.0:attrname-format:uri">
    <saml2:AttributeValue>ssh-rsa LONG KEY</saml2:AttributeValue>
    <saml2:AttributeValue>ssh-rsa LONG KEY 2</saml2:AttributeValue>
</saml2:Attribute>

SAML response requirements

GitHub Enterprise Cloud requires that the response message from your IdP fulfill the following requirements.

• Your IdP must provide the <Destination> element on the root response document and match the ACS URL only when the root response document is signed. If your IdP signs the assertion, GitHub Enterprise Cloud will ignore the assertion.

• Your IdP must always provide the <Audience> element as part of the <AudienceRestriction> element. The value must match your EntityId for GitHub Enterprise Cloud.

  • If you configure SAML for an organization, this value is https://github.com/orgs/ORGANIZATION.
  • If you configure SAML for an enterprise, this URL is https://github.com/enterprises/ENTERPRISE or https://SUBDOMAIN.ghe.com/enterprises/SUBDOMAIN.

• Your IdP must protect each assertion in the response with a digital signature. You can accomplish this by signing each individual <Assertion> element or by signing the <Response> element.

• Your IdP must provide a <NameID> element as part of the <Subject> element. You may use any persistent name identifier format.

• Your IdP must include the Recipient attribute, which must be set to the ACS URL. The following example demonstrates the attribute.

  <samlp:Response ...>
    <saml:Assertion ...>
      <saml:Subject>
        <saml:NameID ...>...</saml:NameID>
        <saml:SubjectConfirmation ...>
          <saml:SubjectConfirmationData Recipient="https://github.com/enterprises/ENTERPRISE/saml/consume" .../>
        </saml:SubjectConfirmation>
      </saml:Subject>
      <saml:AttributeStatement>
        <saml:Attribute FriendlyName="USERNAME-ATTRIBUTE" ...>
          <saml:AttributeValue>monalisa</saml:AttributeValue>
        </saml:Attribute>
      </saml:AttributeStatement>
    </saml:Assertion>
  </samlp:Response>
  

Session duration and timeout

To prevent a person from authenticating with your IdP and staying authorized indefinitely, GitHub Enterprise Cloud periodically invalidates the session for each user account with access to your enterprise's resources. After invalidation, the person must authenticate with your IdP once again.

By default, if your IdP does not assert a value for the SessionNotOnOrAfter attribute, GitHub Enterprise Cloud invalidates a session 24 hours after successful authentication with your IdP.

GitHub Enterprise Cloud will support a customized session duration if your IdP provides the option to configure a SessionNotOnOrAfter attribute and value.

If you define a customized session duration value less than 24 hours, GitHub Enterprise Cloud may prompt people to authenticate every time GitHub Enterprise Cloud initiates a redirect.

To prevent authentication errors, we recommend a minimum session duration of 4 hours. For more information, see Troubleshooting SAML authentication.