clrtrust

Manual section

1

SYNOPSIS

clrtrust is a tool for generating and managing a centralized trusted certificate store.

clrtrust [-v|--verbose] [-h|--help] [-c|--internal-rehash] <command> [options]

DESCRIPTION

A trust store contains a set of X.509 certificates which the operating system and applications should consider trustworthy.

The clrtrust tool provides a frontend for centralized trust store management. It allows for adding (trusting) and removing (distrusting) certificate authorities (CAs). It also provides maintenance commands for viewing and re-generating the trust store.

Certificates can be provided by the operating system for out-of-box functionality. Certificates can also be provided and modified by privileged users.

It is up to each application to make use of the trust store generated by clrtrust.

OPTIONS

Usage: clrtrust [-v|--verbose] [-h|--help] [-c|--internal-rehash] <command> [options]

    -v | --verbose          Shows more details about execution
    -c | --internal-rehash  Forces use of internal implementation of c_rehash
    -h | --help             Prints this message

    Commands
        generate    generates the trust store
        list        list CAs
        add         add trust to a CA
        remove      remove trust to a CA
        restore     restore trust to previously removed CA
        check       sanity/consistency check of the trust store

clrtrust <command> --help to get help on specific command.

Commands that modify the trust store require root privileges.

  • clrtrust generate [-f|--force]

The generate command has no arguments and generates a unified trust store composed of system-provided and user-provided certificates, if any. The optional --force parameter will forcibly generate the trust store, even if it results in an empty store. See the FILES section for paths used for trust store generation.

  • clrtrust list

The list command has no arguments and outputs a list of trusted certificates with the following fields:

id uniquely identifies the certificate. It can be used as input to other clrtrust commands such as remove or restore.

File contains the file path of the certificate in the trust store.

Authority shows the name of the organization that issued the certificate. This field is extracted from the certificate file.

Expires shows the expiration date of the certificate. This field is extracted from the certificate file.

  • clrtust add [<certificateFile> ...] [-f|--force]

The add command takes one or more certificates as required argument(s). The certificate is identified by a file path. The certificate file(s) must be PEM-encoded with only one certificate per file. The optional --force parameter will forcibly add the certificate to the trust store, even if it is not a root CA.

Adding a root CA to the trust store allows applications using the trust store to trust the root CA certificate, trust certificate chains issued by the authority, verify the authenticity of peer’s certificate, and establish a connection.

  • clrtrust remove [<certificateFile|id> ...]

The remove command takes one or more certificates as required argument(s). The certificate is identified by a file path or id. The argument can be an id of the certificate (see the list command) or the file path of the certificate.

Removing a root CA from the trust store distrusts the certificate for applications using the trust store. Certificate chains issued by the authority will no longer be trusted, authenticity of the peer’s certificate will no longer be verified, and a connection will not be established.

  • clrtrust check

The check command has no arguments and validate the consistency of a previously generated unified trust store.

EXAMPLES

View the list of trusted CAs

clrtrust list

The command above outputs a list of trusted certificates in the format below:

id: FA:B7:EE:36:97:26:62:FB:2D:B0:2A:F6:BF:03:FD:E8:7C:4B:2F:9B   File: /var/cache/ca-certs/anchors/certSIGN_ROOT_CA.crt   Authority: /C=RO/O=certSIGN/OU=certSIGN ROOT CA   Expires: Jul  4 17:20:04 2031 GMT

The certificate can be further inspected using the openssl x509 command. For example:

openssl x509 -in /var/cache/ca-certs/anchors/certSIGN_ROOT_CA.crt -noout -text

Add (trust) a root CA

clrtrust add ~/PrivateCA.pem

The command above will add a root CA certificate located in the ~/PrivateCA.pem file. If the certificate file is not in the PEM format, use openssl x509 command to convert to PEM first. For example:

openssl x509 -in PrivateCA.cer -inform der -out PrivateCA.pem -outform pem

Remove (distrust) a root CA

clrtrust remove ~/PrivateCA.pem

The command above will remove a root CA certificate located in the ~/PrivateCA.pem file from the trust store and distrust it.

FILES

/var/cache/ca-certs

Generated directory of certificates and verification keys. Do not modify contents outside of clrtrust.

/usr/share/ca-certs/

Operating-system provided certificates and keys. Do not modify contents outside of clrtrust.

/etc/ca-certs/

Generated directory of user-supplied certificates and verification keys. Do not modify contents outside of clrtrust.

SEE ALSO

openssl(1)