Managing CAs

This Certificate Authority Operations section provides information on managing CAs and instructions on how to create, renew, revoke, and import and export Certificate Authorities (CAs).

For more conceptual information on CAs, see Certificate Authority Overview.

This page primarily covers x509 CAs for secure email, login, web authentication, VPN and so on. For information about CVC CAs for certificates used by EU EAC ePassports and eIDs, see the CVC CA Operations page.

Creating CAs

Once through your first installation, you'll have a default CA created on your instance of EJBCA called the Management CA. This CA is EJBCA's own bootstrap CA, and will be used by you internally from now on in order to issue end user certificates for your administrators.

From here on, you can create the CA of your choice:

• Create a Root CA
• Import an External CA
• Create an Issuing CA Signed by an External Root
• Create an Issuing CA Signed by a Root on Same Node

Creating a CA through EJBCA's WebService API

ENTERPRISE

If EJBCA's web service is set up, it is also possible to create new CA by using the WS API call createCA in your application or with the Web Services CLI.

Requesting a Cross or Bridge Certificate

If you have set up your own CA you can request another CA to cross certify your CA, or you can get certified by Bridge CA such as the Federal Bridge.

Handling the certificate chains on clients is out of the scope for EJBCA.

This is done in the following way:

1. In the Edit CA page, choose a CA that you intend to get cross certified by another CA and click Edit.
2. In the lower part of the screen, click on Make Certificate Request and skip upload of the signing certificate chain.
3. Save the created PKCS#10 certificate request to disk and send to the other CA.

Now you have a certificate request to send to the other CA or Bridge CA. When the other CA has issued a certificate for you, everything is completed. You don't need to (and usually should not) import the cross-certificate or bridge-certificate in EJBCA. What you need to do is make sure the clients using the certificates issued by your CA have access to the correct certificate chain. If you are cross-certified with several other CA, multiple possible certificate chains exist.

If you choose to upload the resulting certificate chain, this will convert your CA from an internal CA to an externally signed CA.

Renewing CAs 

When a CA expires you have the choice of renewing the existing CA, or creating a new CA. Our general recommendation is to create a new CA subject DN when renewing Root CAs, see CA Rekey Recommendations. 

Consider creating a new Root CA instead of re-keying an existing one. Having multiple Root CA certificates with different keys but using the same subject DN may lead to unexpected issues and behavior.

The following describes renewing a CA certificate keeping the same subject DN.

You can renew CAs in different ways:

• Renew only CA certificate, using the same keys.
• Renew CA keys and certificate.

To renew only the CA certificate using the same keys, click Renew CA. Note that your CA must be online to be able to sign the new certificate (if a self-signed CA), or the certificate request (if a sub CA). Additionally, if using a sub CA with the root CA in the same EJBCA instance, the root CA is also required to be online.

When renewing the CA certificate without renewing keys, the same signing key is used as before, and the subject key ID in the CA certificate will stay the same. This option is useful if something in the CA certificate needs to be fixed. To limit the time a Root CA key is used it is considered best practice to do a CA rollover with renewing CA signature keys.

To renew the CA keys, set Next CA key to Generate new key using KeySequence and click Renew CA. Note that not all HSMs support renewal of CA keys.

When using an HSM, manual renewal of keys can also be made by generating new keys on the HSM, using for example the EJBCA CLI tools, and then selecting the generated keys in the Next CA key field and clicking Renew CA.

Using CA Rollover

It is possible to renew a CA certificate, but not activate the new certificate and key immediately. This is useful for CA certificates that will become valid at some point in the future (in EJBCA, such certificates can be created by checking "Allow Validity Override" in the certificate profile). A such certificate is called a rollover certificate or a next CA certificate, and can be used in the SCEP protocol.

First, make a certificate request as usual. Then you may receive the CA certificate response without activating it. To do so, edit the CA and check the "Rollover certificate (activated later)" checkbox. Then select the new CA certificate file its corresponding key. Then click "Receive Certificate Response". A message will appear, which shows when the rollover certificate becomes valid, and may be activated.

At a later point, the new rollover certificate may be activated. To activate it, edit the CA and scroll down to "CA Life Cycle". There should be text telling when the current certificate expires and when the rollover certificate becomes valid. If not, the CA doesn't have any rollover certificate. Click the button "Perform CA Rollover", and the new rollover certificate will be activated.

There is also a service, Rollover Service, that can be configured to activate rollover certificates automatically once they become valid. There will be a 10 minute delay in this case to allow for a small amount of clock skew.

Signing a Rollover Certificate a.k.a Link Certificate

One way to handle update of trust points when renewing a Root CA is to generate a certificate that contains the new key signed with the old key. For X.509 CAs that are simply renewed (keeping the same CA subjectDN), you can create such a certificate by selecting Create link certificate before renewing the CA. The latest link certificate can then be downloaded from the Edit CA view. For CVC CAs a link certificate is always generated during the renewal.

It is possible to change the CA signature algorithm when renewing a CA (albeit it may require some technical steps) and the link certificate will consider this algorithm change (from EJBCA 8.3.0).

ICAO and some other PKI have stated requirements to create link certificates, new-with-old, in order to distribute new Root CA certificates without the need for an out of band secure channel (i.e. clients can verify the new Root certificate with their existing trust anchor). There are many details when it comes to link certificate profiles such as the signature algorithm should be the same as the old CA certificate (if CA changes algorithm), notAfter on the link certificate should be related to the old CA certificate and notBefore to the new CA certificate, and other details. Make sure to check your specification for the required details.

Some RFCs (for example, RFC4210) also specifies an old-with-new link certificate. Although we do not see much practical use of this type of link certificate, it is possible to create such an old-with-new link manually according to the following instructions.

Do not perform the following steps unless you are sure that an old-with-new link certificate is required.

If you need to create an old-with-new link certificate, perform the following steps:

1. Before starting the renewal, create a CSR from the Root CA.
2. Once the renewal is completed, sign the CSR with the new Root CA.
   • Ensure that the CA has the options Enforce unique DN and Enforce unique public keys disabled during this operation.
   • Create a suitable SubCA certificate profile for the OldWithNew link certificate. Use the option Allow Subject DN Override by CSR and configure all attributes desired.
   • Create an end entity profile for the OldWithNew with the proper subject DN naming fields.
   • Issue the certificate, using the CSR from the old CA keys, signing the certificate with the new CA keys.
   • Verify the contents of the certificate carefully and that the correct links verify as they should.

You can use the same process, but reverting New with Old to create a NewWithOld link certificate in the case of a new Root CA, with a different subjectDN, need a link certificate from another (old) Root CA.

Distributing link certificates is out of scope of the rollover functionality itself.

Revoking CAs

When revoking a sub CA, you can choose to only revoke the sub CA certificate or to revoke the sub CA certificate and all certificates issued by the sub CA. A TLS client would normally check the revocation status of each certificate in the certificate chain, in which case revoking only the sub CA certificate would be sufficient.

Revoking a CA Certificate

You revoke a sub CA certificate the same way as you revoke any other certificate in EJBCA. To revoke a sub CA certificate, do the following on the EJBCA instance where the issuer of the sub CA (normally a root CA) resides:

1. Go to the RA Web and select Search → Certificates.
2. Search for the certificate by entering the common name of the sub CA, and click View to view the sub CA certificate.
3. Choose a revocation reason in the certificate status list menu and click Revoke to revoke the sub CA certificate.
4. Go the CA UI and click CA Structure and CRLs.
5. Click Create CRL on the appropriate issuer (root CA) to create a new CRL.
6. Optionally, download and distribute the new CRL to VA instances manually if this is not done automatically with a publisher.

Revoking All Certificates Issued by a CA

You can also revoke all certificates issued by the sub CA. To revoke all certificates issued by the sub CA, do the following on the EJBCA instance where the sub CA resides:

This operation may potentially create a very large CRL if the sub CA has issued a great number of certificates.

1. Go to the CA UI and click Certification Authorities.
2. Select the sub CA whose certificates you want to revoke, and click Edit CA to edit the sub CA.
3. In the CA Life Cycle section, choose a revocation reason and click Revoke to revoke all certificates issued by the sub CA that are not yet revoked. This will also create a new CRL.

If the CA is connected to a VA using peers, the VA will not automatically get the new status of the revoked certificates and you therefore need to synchronize manually as follows:

1. Click Peer Systems in the menu.
2. Click Manage on the appropriate peer connector.
3. In the Certificate Data Synchronization tab, choose Only sync revoked and then click Start to push the status of the revoked certificates to the VA.

Exporting and Importing CAs

Under certain circumstances, it can be wise to back up the CA's signature and encryption keys. Remember to protect the backup in the same way as the CA itself.

• Soft token CAs can be exported and backed up. CAs with the keys on an HSM cannot be exported through EJBCA. Use the HSMs methods to back up such keys. 
• Soft token CAs can be imported using both the CLI and Admin GUI, while HSM CAs can only be imported using the CLI.

The aliases of the keys in exported key stores are important when importing the key stores, and allow you to assign the correct keys. To list the aliases (or friendlyName in OpenSSL terminology) in a PKCS#12 file, use the following OpenSSL command:

$ openssl pkcs12 -in /home/user/tmp/kesytore.p12

Using the CA UI 

To export and import the CA's keys using the CA GU, you need super administrator access. Make sure that .p12 files are not automatically saved to an unsuitable place by your browser before you perform an export.

To export the CA's keys, do the following:

1. Select the Certificate Authorities menu option.
2. Select the CA to export and click Edit.
3. Next to CA export requires the keystore password, enter the keystore password.
4. Click Export CA keystore.
5. The PKCS#12-file will be downloaded by your browser to the location you specify.

To import the CA's keys, do the following:

1. Select the Certificate Authorities menu option.
2. Click Import CA keystore.
3. Specify the CA's name, full pathname to the PKCS#12-file, and keystore password.
4. If you exported the CA's keys using EJBCA, do not edit the two Alias field default values.
5. Click Import CA keystore.

Using Command Line Interface

To export a CA named TestCA to the PKCS#12-file /path/TestCA.p12 with password foo123, enter the following from the $EJBCA_HOME directory:

$ bin/ejbca.sh ca exportca TestCA ./TestCA.p12
Using JBoss JNDI provider...
Enter keystore password: foo123
$

To import the backup keys for TestCA later, enter the following from the $EJBCA_HOME directory:

$ bin/ejbca.sh ca importca TestCA /path/TestCA.p12 SignatureKeyAlias EncryptionKeyAlias
Using JBoss JNDI provider...
Enter keystore password: foo123
$

To view usage instructions on how to import HSM CAs, run the following command:

$ bin/ejbca.sh ca importca --help

If you import multiple CAs that are using the same HSM, and the same slot on the HSM, duplicate crypto tokens are created in EJBCA. Although there should only be one crypto token per slot, one crypto token per CA is created during the import of the CAs. To merge these crypto tokens after the import is complete, use the CLI command mergecatokens:

$ bin/ejbca.sh ca mergecatokens --help

Remove and Restore a CA Soft Key Store 

Soft token CAs can have their keystore removed from the database. When the keystore is removed, the CA cannot issue certificates and its CA token status is set to offline.

Before removing the keystore, export it first to allow restoring it later, see Export and Import CAs above.

To remove the catoken keys for TestCA, enter the following from the $EJBCA_HOME directory:

$ bin/ejbca.sh ca removekeystore TestCA
Using JBoss JNDI provider...
$ 

To restore the catoken keys again for TestCA with the keystore exported as TestCA-exported.p12, enter the following from the $EJBCA_HOME directory:

$ bin/ejbca.sh ca restorekeystore TestCA /path/TestCA-exported.p12 -s SignatureKeyAlias -e EncryptionKeyAlias
Using JBoss JNDI provider...
Enter keystore password: foo123
$