Chapter 3. Using shared system certificates
The shared system certificates storage enables NSS, GnuTLS, OpenSSL, and Java to share a default source for retrieving system certificate anchors and block-list information. By default, the truststore contains the Mozilla CA list, including positive and negative trust. The system allows updating the core Mozilla CA list or choosing another certificate list.
3.1. The system-wide truststore
In RHEL, the consolidated system-wide truststore is located in the /etc/pki/ca-trust/
and /usr/share/pki/ca-trust-source/
directories. The trust settings in /usr/share/pki/ca-trust-source/
are processed with lower priority than settings in /etc/pki/ca-trust/
.
Certificate files are treated depending on the subdirectory they are installed to. For example, trust anchors belong to the /usr/share/pki/ca-trust-source/anchors/
or /etc/pki/ca-trust/source/anchors/
directory.
In a hierarchical cryptographic system, a trust anchor is an authoritative entity that other parties consider trustworthy. In the X.509 architecture, a root certificate is a trust anchor from which a chain of trust is derived. To enable chain validation, the trusting party must have access to the trust anchor first.
Additional resources
-
update-ca-trust(8)
andtrust(1)
man pages
3.2. Adding new certificates
To acknowledge applications on your system with a new source of trust, add the corresponding certificate to the system-wide store, and use the update-ca-trust
command.
Prerequisites
-
The
ca-certificates
package is present on the system.
Procedure
To add a certificate in the simple PEM or DER file formats to the list of CAs trusted on the system, copy the certificate file to the
/usr/share/pki/ca-trust-source/anchors/
or/etc/pki/ca-trust/source/anchors/
directory, for example:# cp ~/certificate-trust-examples/Cert-trust-test-ca.pem /usr/share/pki/ca-trust-source/anchors/
To update the system-wide truststore configuration, use the
update-ca-trust
command:# update-ca-trust
Even though the Firefox browser can use an added certificate without a prior execution of update-ca-trust
, enter the update-ca-trust
command after every CA change. Also note that browsers, such as Firefox, Chromium, and GNOME Web cache files, and you might have to clear your browser’s cache or restart your browser to load the current system certificate configuration.
Additional resources
-
update-ca-trust(8)
andtrust(1)
man pages
3.3. Managing trusted system certificates
The trust
command provides a convenient way for managing certificates in the shared system-wide truststore.
To list, extract, add, remove, or change trust anchors, use the
trust
command. To see the built-in help for this command, enter it without any arguments or with the--help
directive:$ trust usage: trust command <args>... Common trust commands are: list List trust or certificates extract Extract certificates and trust extract-compat Extract trust compatibility bundles anchor Add, remove, change trust anchors dump Dump trust objects in internal format See 'trust <command> --help' for more information
To list all system trust anchors and certificates, use the
trust list
command:$ trust list pkcs11:id=%d2%87%b4%e3%df%37%27%93%55%f6%56%ea%81%e5%36%cc%8c%1e%3f%bd;type=cert type: certificate label: ACCVRAIZ1 trust: anchor category: authority pkcs11:id=%a6%b3%e1%2b%2b%49%b6%d7%73%a1%aa%94%f5%01%e7%73%65%4c%ac%50;type=cert type: certificate label: ACEDICOM Root trust: anchor category: authority ...
To store a trust anchor into the system-wide truststore, use the
trust anchor
sub-command and specify a path to a certificate. Replace <path.to/certificate.crt> by a path to your certificate and its file name:# trust anchor <path.to/certificate.crt>
To remove a certificate, use either a path to a certificate or an ID of a certificate:
# trust anchor --remove <path.to/certificate.crt> # trust anchor --remove "pkcs11:id=<%AA%BB%CC%DD%EE>;type=cert"
Additional resources
All sub-commands of the
trust
commands offer a detailed built-in help, for example:$ trust list --help usage: trust list --filter=<what> --filter=<what> filter of what to export ca-anchors certificate anchors ... --purpose=<usage> limit to certificates usable for the purpose server-auth for authenticating servers ...
Additional resources
-
update-ca-trust(8)
andtrust(1)
man pages