CA handler for XCA

Support for an XCA based Certificate Authorities

This handler can be used to store, certificates and requests in an XCA SQLite database.

It is also possible to fetch enrollment templates from XCA an apply them to certificate signing requests.

Prerequisites

You need to have a ready-made xca database with CA certificate and keys imported. You further need the Internal Name from the Certificate Authorities to be used as show in the XCA application.

Configuration

• copy the ca_handler into the acme directory

root@rlh:~# cp example/ca_handlers/xca_ca_handler.py acme_srv/ca_handler.py

• place the XCA database into a directory which is accessible by acme2certifier.

• modify the server configuration (/acme_srv/acme_srv.cfg) and add the following parameters

[CAhandler]
xdb_file: acme_srv/xca/acme2certifier.xdb
issuing_ca_name: sub-ca
issuing_ca_key: sub-ca-key
passphrase_variable: XCA_PASSPHRASE
ca_cert_chain_list: ["root-ca"]
template_name: XCA template to be applied to CSRs

• xdb_file - path to XCA database
• issuing_ca_name - XCA name of the certificate authority used to issue certificates.
• issuing_ca_key - XCA name of the ley used to sign certificates. If not set same value as configured in issuing_ca_name will be assumed.
• passphrase_variable - optional - name of the environment variable containing the passphrase to decrypt the CA key (a configured passphrase parameter takes precedence)
• passphrase - optional - passphrase to access the database and decrypt the private CA Key
• ca_cert_chain_list - optional - List of root and intermediate CA certificates to be added to the bundle return to an ACME-client (the issuing CA cert must not be included)
• template_name - optional - name of the XCA template to be applied during certificate issuance
• eab_profiling - optional - activate eab profiling (default: False)

Template support has been introduced starting from v0.13. Support is limited to the below parameters which can be applied during certificate issuance:

• Certificate validity (validN/validM)
• basicConstraints (ca)
• KeyUsage attributes (keyUse) - if not included attribute will be defaulted to digitalSignature, nonRepudiation, keyEncipherment, keyAgreement
• extendedKeyUsage attributes (eKeyUse)
• crlDistributionPoints (crlDist)
• Enforcement of the following DN attributes:
  • OU: OrganizationalUnit
  • O: Organization
  • L: Locality
  • S: StateOrProvinceName
  • C: CountryName

eab profiling

This handler can use the eab profiling feture to allow individual enrollment configuration per acme-account as well as restriction of CN and SANs to be submitted within the CSR. The feature is disabled by default and must be activated in acme_srv.cfg

[EABhandler]
eab_handler_file: examples/eab_handler/kid_profile_handler.py
key_file: <profile_file>

[CAhandler]
eab_profiling: True

below an example key-file used during regression testing:

{
  "keyid_00": {
    "hmac": "V2VfbmVlZF9hbm90aGVyX3ZlcnkfX2xvbmdfaG1hY190b19jaGVja19lYWJfZm9yX2tleWlkXzAwX2FzX2xlZ29fZW5mb3JjZXNfYW5faG1hY19sb25nZXJfdGhhbl8yNTZfYml0cw",
    "cahandler": {
      "template_name": ["template", "acme"],
      "allowed_domainlist": ["www.example.com", "www.example.org", "*.acme"],
      "unknown_key": "unknown_value"
    }
  },
  "keyid_01": {
    "hmac": "YW5vdXRoZXJfdmVyeV9sb25nX2htYWNfZm9yX2tleWlkXzAxX3doaWNoIHdpbGxfYmUgdXNlZF9kdXJpbmcgcmVncmVzc2lvbg",
    "cahandler": {
      "template_name": "template",
      "allowed_domainlist": ["www.example.com", "www.example.org", "*.acme"],
      "issuing_ca_name": "root-ca",
      "issuing_ca_key": "root-ca"
    }
  },
  "keyid_02": {
    "hmac": "dGhpc19pc19hX3ZlcnlfbG9uZ19obWFjX3RvX21ha2Vfc3VyZV90aGF0X2l0c19tb3JlX3RoYW5fMjU2X2JpdHM",
    "cahandler": {
      "allowed_domainlist": ["www.example.com", "www.example.org"]
    }
  },
  "keyid_03": {
    "hmac": "YW5kX2ZpbmFsbHlfdGhlX2xhc3RfaG1hY19rZXlfd2hpY2hfaXNfbG9uZ2VyX3RoYW5fMjU2X2JpdHNfYW5kX3Nob3VsZF93b3Jr"
  }
}

Enjoy enrolling and revoking certificates...