pam_env.conf(5) — Linux manual page

PAM_ENV.CONF(5)             Linux-PAM Manual             PAM_ENV.CONF(5)

NAME

       pam_env.conf, environment - the environment variables config
       files

DESCRIPTION

       The /etc/security/pam_env.conf file specifies the environment
       variables to be set, unset or modified by pam_env(8). When
       someone logs in, this file is read and the environment variables
       are set according.

       Each line starts with the variable name, there are then two
       possible options for each variable DEFAULT and OVERRIDE. DEFAULT
       allows an administrator to set the value of the variable to some
       default value, if none is supplied then the empty string is
       assumed. The OVERRIDE option tells pam_env that it should enter
       in its value (overriding the default value) if there is one to
       use. OVERRIDE is not used, "" is assumed and no override will be
       done.

       VARIABLE [DEFAULT=[value]] [OVERRIDE=[value]]

       (Possibly non-existent) environment variables may be used in
       values using the ${string} syntax and (possibly non-existent)
       PAM_ITEMs as well as HOME and SHELL may be used in values using
       the @{string} syntax. Both the $ and @ characters can be
       backslash escaped to be used as literal values values can be
       delimited with "", escaped " not supported. Note that many
       environment variables that you would like to use may not be set
       by the time the module is called. For example, ${HOME} is used
       below several times, but many PAM applications don't make it
       available by the time you need it. The special variables @{HOME}
       and @{SHELL} are expanded to the values for the user from his
       passwd entry.

       The "#" character at start of line (no space at front) can be
       used to mark this line as a comment line.

       The /etc/environment file specifies the environment variables to
       be set. The file must consist of simple NAME=VALUE pairs on
       separate lines. The pam_env(8) module will read the file after
       the pam_env.conf file.

EXAMPLES

       These are some example lines which might be specified in
       /etc/security/pam_env.conf.

       Set the REMOTEHOST variable for any hosts that are remote,
       default to "localhost" rather than not being set at all

                 REMOTEHOST     DEFAULT=localhost OVERRIDE=@{PAM_RHOST}

       Set the DISPLAY variable if it seems reasonable

                 DISPLAY        DEFAULT=${REMOTEHOST}:0.0 OVERRIDE=${DISPLAY}

       Now some simple variables

                 PAGER          DEFAULT=less
                 MANPAGER       DEFAULT=less
                 LESS           DEFAULT="M q e h15 z23 b80"
                 NNTPSERVER     DEFAULT=localhost
                 PATH           DEFAULT=${HOME}/bin:/usr/local/bin:/bin\
                 :/usr/bin:/usr/local/bin/X11:/usr/bin/X11
                 XDG_DATA_HOME  DEFAULT=@{HOME}/share/

       Silly examples of escaped variables, just to show how they work.

                 DOLLAR         DEFAULT=\$
                 DOLLARDOLLAR   DEFAULT=        OVERRIDE=\$${DOLLAR}
                 DOLLARPLUS     DEFAULT=\${REMOTEHOST}${REMOTEHOST}
                 ATSIGN         DEFAULT=""      OVERRIDE=\@

SEE ALSO

       pam_env(8), pam.d(5), pam(8), environ(7)

AUTHOR

       pam_env was written by Dave Kinchlea <kinch@kinch.ark.com>.

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
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to
       man-pages@man7.org

Linux-PAM Manual               12/22/2023                PAM_ENV.CONF(5)

Pages that refer to this page: pam_env(8)

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