PKCHECK(1)

NAME
pkcheck - Check whether a process is authorized

SYNOPSIS

pkcheck [--version] [--help|-h]

pkcheck [--list-temp]

pkcheck [--revoke-temp]

pkcheck --action-id|-a action {--process|-p { pid | pid,pid-start-time | pid,pid-start-time,uid } | --system-bus-name|-s busname} [--allow-user-interaction|-u] [--enable-internal-agent] [--detail|-d key value...]

DESCRIPTION

pkcheck is used to check whether a process, specified by either --process (see below) or --system-bus-name, is authorized for action. The --detail option can be used zero or more times to pass details about action. If --allow-user-interaction is passed, pkcheck blocks while waiting for authentication.

The invocation pkcheck --list-temp will list all temporary authorizations for the current session and pkcheck --revoke-temp will revoke all temporary authorizations for the current session.

This command is a simple wrapper around the polkit D-Bus interface; see the D-Bus interface documentation for details.

RETURN VALUE

If the specified process is authorized, pkcheck exits with a return value of 0. If the authorization result contains any details, these are printed on standard output as key/value pairs using environment style reporting, e.g. first the key followed by a an equal sign, then the value followed by a newline.

    KEY1=VALUE1
    KEY2=VALUE2
    KEY3=VALUE3
    ...

Octets that are not in [a-zA-Z0-9_] are escaped using octal codes prefixed with \. For example, the UTF-8 string føl,你好 will be printed as f\303\270l\54\344\275\240\345\245\275.

If the specified process is not authorized, pkcheck exits with a return value of 1 and a diagnostic message is printed on standard error. Details are printed on standard output.

If the specified process is not authorized because no suitable authentication agent is available or if the --allow-user-interaction wasn't passed, pkcheck exits with a return value of 2 and a diagnostic message is printed on standard error. Details are printed on standard output.

If the specified process is not authorized because the authentication dialog / request was dismissed by the user, pkcheck exits with a return value of 3 and a diagnostic message is printed on standard error. Details are printed on standard output.

If an error occurred while checking for authorization, pkcheck exits with a return value of 127 with a diagnostic message printed on standard error.

If one or more of the options passed are malformed, pkcheck exits with a return value of 126. If stdin is a tty, then this manual page is also shown.

NOTES

Do not use either the bare pid or pid,start-time syntax forms for --process. There are race conditions in both. New code should always use pid,pid-start-time,uid. The value of start-time can be determined by consulting e.g. the proc(5) file system depending on the operating system. If fewer than 3 arguments are passed, pkcheck will attempt to look up them up internally, but note that this may be racy.

If your program is a daemon with e.g. a custom Unix domain socket, you should determine the uid parameter via operating system mechanisms such as PEERCRED.

AUTHENTICATION AGENT

pkcheck, like any other polkit application, will use the authentication agent registered for the process in question. However, if no authentication agent is available, then pkcheck can register its own textual authentication agent if the option --enable-internal-agent is passed.

AUTHOR

Written by David Zeuthen <davidz@redhat.com> with a lot of help from many others.

BUGS

Please send bug reports to either the distribution or the polkit-devel mailing list, see the link https://gitlab.freedesktop.org/polkit/polkit/-/issues/ on how to subscribe.

SEE ALSO

polkit(8), polkitd(8), pkaction(1), pkexec(1), pkttyagent(1)