Deploy User-Specific Client Certificates for Authentication

To authenticate individual users, you must issue a unique client certificate to each GlobalProtect user and deploy the client certificate to the endpoints prior to enabling GlobalProtect. To automate the generation and deployment of user-specific client certificates, you can configure your GlobalProtect portal to act as a Simple Certificate Enrollment Protocol (SCEP) client to a SCEP server in your enterprise PKI.
SCEP operation is dynamic in that the enterprise PKI generates a user-specific certificate when the portal requests it and sends the certificate to the portal. The portal then transparently deploys the certificate to the client. When a user requests access, the agent or app can then present the client certificate to authenticate with the portal or gateway.
The GlobalProtect portal or gateway uses identifying information about the device and user to evaluate whether to permit access to the user. GlobalProtect blocks access if the host ID is on a device block list or if the session matches any blocking options specified in a certificate profile. If client authentication fails due to an invalid SCEP-based client certificate, the GlobalProtect client tries to authenticate with the portal per the settings in the authentication profile and retrieve the certificate. If the client cannot retrieve the certificate from the portal, the device is not able to connect.
  1. Create a SCEP profile.
    1. Select
      Device
      Certificate Management
      SCEP
      and then
      Add
      a new profile.
    2. Enter a
      Name
      to identify the SCEP profile.
    3. If this profile is for a firewall with multiple virtual systems capability, select a virtual system or
      Shared
      as the
      Location
      where the profile is available.
  2. (
    Optional
    ) To make the SCEP-based certificate generation more secure, configure a SCEP challenge-response mechanism between the PKI and portal for each certificate request.
    After you configure this mechanism, its operation is invisible, and no further input from you is necessary.
    To comply with the U.S. Federal Information Processing Standard (FIPS), use a
    Dynamic
    SCEP challenge and specify a
    Server URL
    that uses HTTPS (see 7).
    Select one of the following options:
    • None
      —(
      Default
      ) The SCEP server does not challenge the portal before it issues a certificate.
    • Fixed
      —Obtain the enrollment challenge password from the SCEP server in the PKI infrastructure and then enter the password into the Password field.
    • Dynamic
      —Enter a username and password of your choice (possibly the credentials of the PKI administrator) and the SCEP
      Server URL
      where the portal-client submits these credentials. The uses the credentials to authenticate with the SCEP server which transparently generates an OTP password for the portal upon each certificate request. (You can see this OTP change after a screen refresh in
      The enrollment challenge password is
      field after each certificate request.) The PKI transparently passes each new password to the portal, which then uses the password for its certificate request.
  3. Specify the settings for the connection between the SCEP server and the portal to enable the portal to request and receive client certificates.
    You can include additional information about the client device or user by specifying tokens in the
    Subject
    name of the certificate.
    In the Subject field of the CSR to the SCEP server, the portal includes the token value as CN and Host-ID as SerialNumber. The host ID varies by device type: GUID (Windows) MAC address of the interface (Mac), Android ID (Android devices), UDID (iOS devices), or a unique name that GlobalProtect assigns (Chrome).
    1. Configure the
      Server URL
      that the portal uses to reach the SCEP server in the PKI (for example,
      http://10.200.101.1/certsrv/mscep/
      ).
    2. Enter a string (up to 255 characters in length) in the
      CA-IDENT Name
      field to identify the SCEP server.
    3. Enter the
      Subject
      name to use in the certificates generated by the SCEP server. The subject must be a distinguished name in the
      <attribute>
      =
      <value>
      format and must include a common name (CN) attribute (
      CN=
      <token>
      ). The CN supports the following dynamic tokens:
      • $USERNAME
        —Use this token to enable the portal to request certificates for a specific user. To use this variable, you must also Enable Group Mapping. The username entered by the user must match the name in the user-group mapping table.
      • $EMAILADDRESS
        —Use this token to request certificates associated with a specific email address. To use this variable, you must also Enable Group Mapping and configure the
        Mail Attributes
        in the Mail Domains section of the Server Profile. If GlobalProtect cannot identify an email address for the user, it generates a unique ID and populates the CN with that value.
      • $HOSTID
        —To request certificates for the device only, specify the host ID token. When a user attempts to log in to the portal, the endpoint sends identifying information that includes its host ID value.
      When the GlobalProtect portal pushes the SCEP settings to the agent, the CN portion of the subject name is replaced with the actual value (username, host ID, or email address) of the certificate owner (for example,
      O=acme,CN=johndoe
      ).
    4. Select the
      Subject Alternative Name Type
      :
      • RFC 822 Name
        —Enter the email name in a certificate’s subject or Subject Alternative Name extension.
      • DNS Name
        —Enter the DNS name used to evaluate certificates.
      • Uniform Resource Identifier
        —Enter the name of the resource from which the client will obtain the certificate.
      • None
        —Do not specify attributes for the certificate.
  4. (
    Optional
    ) Configure cryptographic settings for the certificate.
    • Select the key length (
      Number of Bits
      ) for the certificate.
      If the firewall is in FIPS-CC mode and the key generation algorithm is RSA. The RSA keys must be 2,048 bits or larger.
    • Select the
      Digest for CSR
      which indicates the digest algorithm for the certificate signing request (CSR): sha1, sha256, or sha384.
    Sha512 is not supported as a digest algorithm for client certificates on GlobalProtect endpoints.
  5. (
    Optional
    ) Configure the permitted uses of the certificate, either for signing or encryption.
    • To use this certificate for signing, select the
      Use as digital signature
      check box. This enables the endpoint use the private key in the certificate to validate a digital signature.
    • To use this certificate for encryption, select the
      Use for key encipherment
      check box. This enables the client use the private key in the certificate to encrypt data exchanged over the HTTPS connection established with the certificates issued by the SCEP server.
  6. (
    Optional
    ) To ensure that the portal is connecting to the correct SCEP server, enter the
    CA Certificate Fingerprint
    . Obtain this fingerprint from the SCEP server interface in the Thumbprint field.
    1. Enter the URL for the SCEP server’s administrative UI (for example,
      http://<hostname or IP>/CertSrv/mscep_admin/
      ).
    2. Copy the thumbprint and enter it in the
      CA Certificate Fingerprint
      field.
  7. Enable mutual SSL authentication between the SCEP server and the GlobalProtect portal. This is required to comply with the U.S. Federal Information Processing Standard (FIPS).
    FIPS-CC operation is indicated on the firewall login page and in its status bar.
    Select the SCEP server’s root
    CA Certificate
    . Optionally, you can enable mutual SSL authentication between the SCEP server and the GlobalProtect portal by selecting a
    Client Certificate
    .
  8. Save and commit the configuration.
    1. Click
      OK
      to save the settings and close the SCEP configuration.
    2. Commit
      the configuration.
    The portal attempts to request a CA certificate using the settings in the SCEP profile and saves it to the firewall hosting the portal. If successful, the CA certificate is shown in
    Device
    Certificate Management
    Certificates
    .
  9. (
    Optional
    ) If after saving the SCEP profile, the portal fails to obtain the certificate, you can manually generate a certificate signing request (CSR) from the portal.
    1. Select
      Device
      Certificate Management
      Certificates
      Device Certificates
      and then click
      Generate
      .
    2. Enter a
      Certificate Name
      . This name cannot contain spaces.
    3. Select the
      SCEP Profile
      to use to submit a CSR to your enterprise PKI.
    4. Click
      OK
      to submit the request and generate the certificate.
  10. Assign the SCEP profile a GlobalProtect portal agent configuration to enable the portal to transparently request and deploy client certificates to clients that receive the configuration.

Related Documentation