Deploy Certificates Using SCEP
If you have a Simple Certificate Enrollment Protocol (SCEP) server in your enterprise PKI, you can configure a SCEP profile to automate the generation and distribution of unique client certificates. SCEP operation is dynamic in that the enterprise PKI generates a user-specific certificate when the SCEP client requests it and sends the certificate to the SCEP client. The SCEP client then transparently deploys the certificate to the client device.
You can use a SCEP profile with GlobalProtect to assign user-specific client certificates to each GlobalProtect user. In this use case, the GlobalProtect portal acts as a SCEP client to the SCEP server in your enterprise PKI. Additionally, you can use a SCEP profile to assign client certificates to Palo Alto Networks devices for mutual authentication with other Palo Alto Networks devices for management access and inter-device communication.
- Create a SCEP profile.
- Selectand thenDeviceCertificate ManagementSCEPAdda new profile.
- Enter aNameto identify the SCEP profile.
- If this profile is for a firewall with multiple virtual systems capability, select a virtual system orSharedas theLocationwhere the profile is available.
- (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 aDynamicSCEP challenge and specify aServer URLthat uses HTTPS.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 SCEPServer URLwhere 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 inThe enrollment challenge password isfield after each certificate request.) The PKI transparently passes each new password to the portal, which then uses the password for its certificate request.
- 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 theSubjectname of the certificate.The portal includes the token value and host ID in the CSR request to the SCEP server.
- Configure theServer URLthat the portal uses to reach the SCEP server in the PKI (for example,http://10.200.101.1/certsrv/mscep/).
- Enter a string (up to 255 characters in length) in theCA-IDENT Namefield to identify the SCEP server.
- Enter theSubjectname 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=<variable>). The CN supports the following dynamic tokens:
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).
- $USERNAME—Use this token to enable the portal to request certificates for a specific user. To use this variable with GlobalProtect, 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 theMail Attributesin 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. The host ID value varies by device type, either GUID (Windows) MAC address of the interface (Mac), Android ID (Android devices), UDID (iOS devices), or a unique name that GlobalProtect assigns (Chrome).
- $UDID—Use the UDID common name attribute to request certificates based on the client’s device UDID for GlobalProtect or device serial number for mutual authentication between Palo Alto Networks devices.
- Select theSubject 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.
- (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 theDigest for CSRwhich indicates the digest algorithm for the certificate signing request (CSR): sha1, sha256, or sha384.
- (Optional) Configure the permitted uses of the certificate, either for signing or encryption.
- To use this certificate for signing, select theUse as digital signaturecheck box. This enables the endpoint use the private key in the certificate to validate a digital signature.
- To use this certificate for encryption, select theUse for key enciphermentcheck 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.
- (Optional) To ensure that the portal is connecting to the correct SCEP server, enter theCA Certificate Fingerprint. Obtain this fingerprint from the SCEP server interface in the Thumbprint field.
- Enter the URL for the SCEP server’s administrative UI (for example,http://<hostname or IP>/CertSrv/mscep_admin/).
- Copy the thumbprint and enter it in theCA Certificate Fingerprintfield.
- Enable mutual SSL authentication between the SCEP server and the firewall. 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 rootCA Certificate. Optionally, you can enable mutual SSL authentication between the SCEP server and the firewall by selecting aClient Certificate.
- Save and 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.DeviceCertificate ManagementCertificates
- ClickOKto save the settings and close the SCEP configuration.
- Committhe configuration.
- (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.
- Selectand then clickDeviceCertificate ManagementCertificatesDevice CertificatesGenerate.
- Enter aCertificate Name. This name cannot contain spaces.
- Select theSCEP Profileto use to submit a CSR to your enterprise PKI.
- ClickOKto submit the request and generate the certificate.