pam_usertype(8) — Linux manual page

PAM_USERTYPE(8)                 Linux-PAM                 PAM_USERTYPE(8)

NAME         top

       pam_usertype - check if the authenticated user is a system or
       regular account

SYNOPSIS         top

       pam_usertype.so [flag...] {condition}

DESCRIPTION         top

       pam_usertype.so is designed to succeed or fail authentication
       based on type of the account of the authenticated user. The type
       of the account is decided with help of SYS_UID_MAX settings in
       /etc/login.defs. One use is to select whether to load other
       modules based on this test.

       The module should be given only one condition as module argument.
       Authentication will succeed only if the condition is met.

OPTIONS         top

       The following flags are supported:

       use_uid
           Evaluate conditions using the account of the user whose UID
           the application is running under instead of the user being
           authenticated.

       audit
           Log unknown users to the system log.

       Available conditions are:

       issystem
           Succeed if the user is a system user.

       isregular
           Succeed if the user is a regular user.

MODULE TYPES PROVIDED         top

       All module types (account, auth, password and session) are
       provided.

RETURN VALUES         top

       PAM_SUCCESS
           The condition was true.

       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_AUTH_ERR
           The condition was false.

       PAM_SERVICE_ERR
           A service error occurred or the arguments can't be parsed
           correctly.

       PAM_USER_UNKNOWN
           User was not found.

EXAMPLES         top

       Skip remaining modules if the user is a system user:

           account sufficient pam_usertype.so issystem

SEE ALSO         top

       login.defs(5), pam(8)

AUTHOR         top

       Pavel Březina <pbrezina@redhat.com>

COLOPHON         top

       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                       12/22/2023                PAM_USERTYPE(8)

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