PKI stands for Public Key Infrastructure. Tokens are documents, cryptographically signed using the X509 standard. In order to work correctly token generation requires a public/private key pair. The public key must be signed in an X509 certificate, and the certificate used to sign it must be available as Certificate Authority (CA) certificate. These files can be generated either using the keystone-manage utility, or externally generated. The files need to be in the locations specified by the top level Identity Service configuration file keystone.conf as specified in the above section. Additionally, the private key should only be readable by the system user that will run the Identity Service. The certificates can be world readable, but the private key cannot be. The private key should only be readable by the account that is going to sign tokens. When generating files with the keystone-manage pki_setup command, your best option is to run as the pki user. If you run keystone-manage as root, you can append --keystone-user and --keystone-group parameters to set the user name and group keystone is going to run under. The values that specify where to read the certificates are under the [signing] section of the configuration file. The configuration values are: token_format - Determines the algorithm used to generate tokens. Can be either UUID or PKI. Defaults to PKI. certfile - Location of certificate used to verify tokens. Default is /etc/keystone/ssl/certs/signing_cert.pem. keyfile - Location of private key used to sign tokens. Default is /etc/keystone/ssl/private/signing_key.pem. ca_certs - Location of certificate for the authority that issued the above certificate. Default is /etc/keystone/ssl/certs/ca.pem. key_size - Default is 1024. valid_days - Default is 3650. ca_password - Password required to read the ca_file. Default is None. If token_format=UUID, a typical token looks like 53f7f6ef0cc344b5be706bcc8b1479e1. If token_format=PKI, a typical token is a much longer string, such as: MIIKtgYJKoZIhvcNAQcCoIIKpzCCCqMCAQExCTAHBgUrDgMCGjCCCY8GCSqGSIb3DQEHAaCCCYAEggl8eyJhY2Nlc3MiOiB7InRva2VuIjogeyJpc3N1ZWRfYXQiOiAiMjAxMy0wNS0z MFQxNTo1MjowNi43MzMxOTgiLCAiZXhwaXJlcyI6ICIyMDEzLTA1LTMxVDE1OjUyOjA2WiIsICJpZCI6ICJwbGFjZWhvbGRlciIsICJ0ZW5hbnQiOiB7ImRlc2NyaXB0aW9uIjogbnVs bCwgImVuYWJsZWQiOiB0cnVlLCAiaWQiOiAiYzJjNTliNGQzZDI4NGQ4ZmEwOWYxNjljYjE4MDBlMDYiLCAibmFtZSI6ICJkZW1vIn19LCAic2VydmljZUNhdGFsb2ciOiBbeyJlbmRw b2ludHMiOiBbeyJhZG1pblVSTCI6ICJodHRwOi8vMTkyLjE2OC4yNy4xMDA6ODc3NC92Mi9jMmM1OWI0ZDNkMjg0ZDhmYTA5ZjE2OWNiMTgwMGUwNiIsICJyZWdpb24iOiAiUmVnaW9u T25lIiwgImludGVybmFsVVJMIjogImh0dHA6Ly8xOTIuMTY4LjI3LjEwMDo4Nzc0L3YyL2MyYzU5YjRkM2QyODRkOGZhMDlmMTY5Y2IxODAwZTA2IiwgImlkIjogIjFmYjMzYmM5M2Y5 ODRhNGNhZTk3MmViNzcwOTgzZTJlIiwgInB1YmxpY1VSTCI6ICJodHRwOi8vMTkyLjE2OC4yNy4xMDA6ODc3NC92Mi9jMmM1OWI0ZDNkMjg0ZDhmYTA5ZjE2OWNiMTgwMGUwNiJ9XSwg ImVuZHBvaW50c19saW5rcyI6IFtdLCAidHlwZSI6ICJjb21wdXRlIiwgIm5hbWUiOiAibm92YSJ9LCB7ImVuZHBvaW50cyI6IFt7ImFkbWluVVJMIjogImh0dHA6Ly8xOTIuMTY4LjI3 LjEwMDozMzMzIiwgInJlZ2lvbiI6ICJSZWdpb25PbmUiLCAiaW50ZXJuYWxVUkwiOiAiaHR0cDovLzE5Mi4xNjguMjcuMTAwOjMzMzMiLCAiaWQiOiAiN2JjMThjYzk1NWFiNDNkYjhm MGU2YWNlNDU4NjZmMzAiLCAicHVibGljVVJMIjogImh0dHA6Ly8xOTIuMTY4LjI3LjEwMDozMzMzIn1dLCAiZW5kcG9pbnRzX2xpbmtzIjogW10sICJ0eXBlIjogInMzIiwgIm5hbWUi OiAiczMifSwgeyJlbmRwb2ludHMiOiBbeyJhZG1pblVSTCI6ICJodHRwOi8vMTkyLjE2OC4yNy4xMDA6OTI5MiIsICJyZWdpb24iOiAiUmVnaW9uT25lIiwgImludGVybmFsVVJMIjog Imh0dHA6Ly8xOTIuMTY4LjI3LjEwMDo5MjkyIiwgImlkIjogIjczODQzNTJhNTQ0MjQ1NzVhM2NkOTVkN2E0YzNjZGY1IiwgInB1YmxpY1VSTCI6ICJodHRwOi8vMTkyLjE2OC4yNy4x MDA6OTI5MiJ9XSwgImVuZHBvaW50c19saW5rcyI6IFtdLCAidHlwZSI6ICJpbWFnZSIsICJuYW1lIjogImdsYW5jZSJ9LCB7ImVuZHBvaW50cyI6IFt7ImFkbWluVVJMIjogImh0dHA6 Ly8xOTIuMTY4LjI3LjEwMDo4Nzc2L3YxL2MyYzU5YjRkM2QyODRkOGZhMDlmMTY5Y2IxODAwZTA2IiwgInJlZ2lvbiI6ICJSZWdpb25PbmUiLCAiaW50ZXJuYWxVUkwiOiAiaHR0cDov LzE5Mi4xNjguMjcuMTAwOjg3NzYvdjEvYzJjNTliNGQzZDI4NGQ4ZmEwOWYxNjljYjE4MDBlMDYiLCAiaWQiOiAiMzQ3ZWQ2ZThjMjkxNGU1MGFlMmJiNjA2YWQxNDdjNTQiLCAicHVi bGljVVJMIjogImh0dHA6Ly8xOTIuMTY4LjI3LjEwMDo4Nzc2L3YxL2MyYzU5YjRkM2QyODRkOGZhMDlmMTY5Y2IxODAwZTA2In1dLCAiZW5kcG9pbnRzX2xpbmtzIjogW10sICJ0eXBl IjogInZvbHVtZSIsICJuYW1lIjogImNpbmRlciJ9LCB7ImVuZHBvaW50cyI6IFt7ImFkbWluVVJMIjogImh0dHA6Ly8xOTIuMTY4LjI3LjEwMDo4NzczL3NlcnZpY2VzL0FkbWluIiwg InJlZ2lvbiI6ICJSZWdpb25PbmUiLCAiaW50ZXJuYWxVUkwiOiAiaHR0cDovLzE5Mi4xNjguMjcuMTAwOjg3NzMvc2VydmljZXMvQ2xvdWQiLCAiaWQiOiAiMmIwZGMyYjNlY2U4NGJj YWE1NDAzMDMzNzI5YzY3MjIiLCAicHVibGljVVJMIjogImh0dHA6Ly8xOTIuMTY4LjI3LjEwMDo4NzczL3NlcnZpY2VzL0Nsb3VkIn1dLCAiZW5kcG9pbnRzX2xpbmtzIjogW10sICJ0 eXBlIjogImVjMiIsICJuYW1lIjogImVjMiJ9LCB7ImVuZHBvaW50cyI6IFt7ImFkbWluVVJMIjogImh0dHA6Ly8xOTIuMTY4LjI3LjEwMDozNTM1Ny92Mi4wIiwgInJlZ2lvbiI6ICJS ZWdpb25PbmUiLCAiaW50ZXJuYWxVUkwiOiAiaHR0cDovLzE5Mi4xNjguMjcuMTAwOjUwMDAvdjIuMCIsICJpZCI6ICJiNTY2Y2JlZjA2NjQ0ZmY2OWMyOTMxNzY2Yjc5MTIyOSIsICJw dWJsaWNVUkwiOiAiaHR0cDovLzE5Mi4xNjguMjcuMTAwOjUwMDAvdjIuMCJ9XSwgImVuZHBvaW50c19saW5rcyI6IFtdLCAidHlwZSI6ICJpZGVudGl0eSIsICJuYW1lIjogImtleXN0 b25lIn1dLCAidXNlciI6IHsidXNlcm5hbWUiOiAiZGVtbyIsICJyb2xlc19saW5rcyI6IFtdLCAiaWQiOiAiZTVhMTM3NGE4YTRmNDI4NWIzYWQ3MzQ1MWU2MDY4YjEiLCAicm9sZXMi OiBbeyJuYW1lIjogImFub3RoZXJyb2xlIn0sIHsibmFtZSI6ICJNZW1iZXIifV0sICJuYW1lIjogImRlbW8ifSwgIm1ldGFkYXRhIjogeyJpc19hZG1pbiI6IDAsICJyb2xlcyI6IFsi YWRiODM3NDVkYzQzNGJhMzk5ODllNjBjOTIzYWZhMjgiLCAiMzM2ZTFiNjE1N2Y3NGFmZGJhNWUwYTYwMWUwNjM5MmYiXX19fTGB-zCB-AIBATBcMFcxCzAJBgNVBAYTAlVTMQ4wDAYD VQQIEwVVbnNldDEOMAwGA1UEBxMFVW5zZXQxDjAMBgNVBAoTBVVuc2V0MRgwFgYDVQQDEw93d3cuZXhhbXBsZS5jb20CAQEwBwYFKw4DAhowDQYJKoZIhvcNAQEBBQAEgYCAHLpsEs2R nouriuiCgFayIqCssK3SVdhOMINiuJtqv0sE-wBDFiEj-Prcudqlz-n+6q7VgV4mwMPszz39-rwp+P5l4AjrJasUm7FrO-4l02tPLaaZXU1gBQ1jUG5e5aL5jPDP08HbCWuX6wr-QQQB SrWY8lF3HrTcJT23sZIleg==

You can use a signing certificate issued by an external CA instead of generated by keystone-manage. However, a certificate issued by an external CA must satisfy the following conditions: all certificate and key files must be in Privacy Enhanced Mail (PEM) format private key files must not be protected by a password When using signing certificate issued by an external CA, you do not need to specify key_size, valid_days, and ca_password as they will be ignored. The basic workflow for using a signing certificate issued by an external CA involves: Request Signing Certificate from External CA Convert certificate and private key to PEM if needed Install External Signing Certificate

One way to request a signing certificate from an external CA is to first generate a PKCS #10 Certificate Request Syntax (CRS) using OpenSSL CLI. Create a certificate request configuration file. For example, create the cert_req.conf file, as follows: [ req ] default_bits = 1024 default_keyfile = keystonekey.pem default_md = sha1 prompt = no distinguished_name = distinguished_name [ distinguished_name ] countryName = US stateOrProvinceName = CA localityName = Sunnyvale organizationName = OpenStack organizationalUnitName = Keystone commonName = Keystone Signing emailAddress = keystone@openstack.org Then generate a CRS with OpenSSL CLI. Do not encrypt the generated private key. Must use the -nodes option. For example: $ openssl req -newkey rsa:1024 -keyout signing_key.pem -keyform PEM \ -out signing_cert_req.pem -outform PEM -config cert_req.conf -nodes If everything is successful, you should end up with signing_cert_req.pem and signing_key.pem. Send signing_cert_req.pem to your CA to request a token signing certificate and make sure to ask the certificate to be in PEM format. Also, make sure your trusted CA certificate chain is also in PEM format.

Assuming you have the following already: signing_cert.pem - (Keystone token) signing certificate in PEM format signing_key.pem - corresponding (non-encrypted) private key in PEM format cacert.pem - trust CA certificate chain in PEM format Copy the above to your certificate directory. For example: # mkdir -p /etc/keystone/ssl/certs # cp signing_cert.pem /etc/keystone/ssl/certs/ # cp signing_key.pem /etc/keystone/ssl/certs/ # cp cacert.pem /etc/keystone/ssl/certs/ # chmod -R 700 /etc/keystone/ssl/certs Make sure the certificate directory is only accessible by root. The copying of the key and cert files may be better done after first running keystone-manage pki_setup since this command also creates other needed files, such as the index.txt and serial files. Also, when copying the necessary files to a different server for replicating the functionality, the entire directory of files is needed, not just the key and cert files. If your certificate directory path is different from the default /etc/keystone/ssl/certs, make sure it is reflected in the [signing] section of the configuration file.