pam_exec(8) — Linux manual page
PAM_EXEC(8) Linux-PAM Manual PAM_EXEC(8)
NAME
pam_exec - PAM module which calls an external command
SYNOPSIS
pam_exec.so [debug] [expose_authtok] [seteuid] [quiet]
[quiet_log] [stdout] [log=file] [type=type] command
[...]
DESCRIPTION
pam_exec is a PAM module that can be used to run an external
command.
The child's environment is set to the current PAM environment
list, as returned by pam_getenvlist(3) In addition, the following
PAM items are exported as environment variables: PAM_RHOST,
PAM_RUSER, PAM_SERVICE, PAM_TTY, PAM_USER and PAM_TYPE, which
contains one of the module types: account, auth, password,
open_session and close_session.
Commands called by pam_exec need to be aware of that the user can
have control over the environment.
OPTIONS
debug
Print debug information.
expose_authtok
During authentication the calling command can read the
password from stdin(3). Only first PAM_MAX_RESP_SIZE bytes of
a password are provided to the command.
log=file
The output of the command is appended to file
type=type
Only run the command if the module type matches the given
type.
stdout
Per default the output of the executed command is written to
/dev/null. With this option, the stdout output of the
executed command is redirected to the calling application.
It's in the responsibility of this application what happens
with the output. The log option is ignored.
quiet
Per default pam_exec.so will echo the exit status of the
external command if it fails. Specifying this option will
suppress the message.
quiet_log
Per default pam_exec.so will log the exit status of the
external command if it fails. Specifying this option will
suppress the log message.
seteuid
Per default pam_exec.so will execute the external command
with the real user ID of the calling process. Specifying this
option means the command is run with the effective user ID.
MODULE TYPES PROVIDED
All module types (auth, account, password and session) are
provided.
RETURN VALUES
PAM_SUCCESS
The external command was run successfully.
PAM_BUF_ERR
Memory buffer error.
PAM_CONV_ERR
The conversation method supplied by the application failed to
obtain the username.
PAM_INCOMPLETE
The conversation method supplied by the application returned
PAM_CONV_AGAIN.
PAM_SERVICE_ERR
No argument or a wrong number of arguments were given.
PAM_SYSTEM_ERR
A system error occurred or the command to execute failed.
PAM_IGNORE
pam_setcred was called, which does not execute the command.
Or, the value given for the type= parameter did not match the
module type.
EXAMPLES
Add the following line to /etc/pam.d/passwd to rebuild the NIS
database after each local password change:
password optional pam_exec.so seteuid /usr/bin/make -C /var/yp
This will execute the command
make -C /var/yp
with effective user ID.
SEE ALSO
pam.conf(5), pam.d(5), pam(8)
AUTHOR
pam_exec was written by Thorsten Kukuk <kukuk@thkukuk.de> and
Josh Triplett <josh@joshtriplett.org>.
COLOPHON
This page is part of the linux-pam (Pluggable Authentication
Modules for Linux) project. Information about the project can be
found at ⟨http://www.linux-pam.org/⟩. If you have a bug report
for this manual page, see ⟨//www.linux-pam.org/⟩. This page was
obtained from the project's upstream Git repository
⟨https://github.com/linux-pam/linux-pam.git⟩ on 2023-12-22. (At
that time, the date of the most recent commit that was found in
the repository was 2023-12-18.) If you discover any rendering
problems in this HTML version of the page, or you believe there
is a better or more up-to-date source for the page, or you have
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(which is not part of the original manual page), send a mail to
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