pam_canonicalize_user(8) — Linux manual page

PAM_CANONICALIZE_USE(8)      Linux-PAM Manual     PAM_CANONICALIZE_USE(8)

NAME         top

       pam_canonicalize_user - Get user name and canonicalize it

SYNOPSIS         top

       pam_canonicalize_user.so

DESCRIPTION         top

       This PAM module uses the name of the user obtained via
       pam_get_user(3) as a key to query the password database, and
       replaces PAM_USER with the pw_name value that has been returned.

OPTIONS         top

       This module does not recognise any options.

MODULE TYPES PROVIDED         top

       Only the auth module type is provided.

RETURN VALUES         top

       PAM_IGNORE
           The user name was set successfully.

       PAM_USER_UNKNOWN
           The user was not found.

       PAM_SYSTEM_ERR
           The application did not supply neither a user name nor a
           conversation method.

       PAM_INCOMPLETE
           The conversation method supplied by the application is waiting
           for an event.

       PAM_CONV_ERR
           The conversation method supplied by the application failed to
           obtain the user name.

       PAM_ABORT
           Error resuming an old conversation.

       PAM_BUF_ERR
           Memory buffer error.

EXAMPLES         top

       Prepend the PAM auth stack with the following line to canonicalize
       the user name before the authentication:

                   auth required pam_canonicalize_user.so

SEE ALSO         top

       pam_get_user(3), pam_get_item(3), pam_set_item(3), getpwnam(3),
       pam.conf(5), pam.d(5), pam(8)

AUTHOR         top

       pam_canonicalize_user was written by Dmitry V. Levin
       <ldv@strace.io>.

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 2026-01-16.  (At
       that time, the date of the most recent commit that was found in
       the repository was 2026-01-12.)  If you discover any rendering
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       (which is not part of the original manual page), send a mail to
       man-pages@man7.org

Linux-PAM                       01/16/2026        PAM_CANONICALIZE_USE(8)

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