csu3_am335x/EVSE/GPL/linux-pam-1.5.2/doc/man/pam_set_data.3

'\" t
.\"     Title: pam_set_data
.\"    Author: [FIXME: author] [see http://docbook.sf.net/el/author]
.\" Generator: DocBook XSL Stylesheets v1.79.1 <http://docbook.sf.net/>
.\"      Date: 09/03/2021
.\"    Manual: Linux-PAM Manual
.\"    Source: Linux-PAM Manual
.\"  Language: English
.\"
.TH "PAM_SET_DATA" "3" "09/03/2021" "Linux-PAM Manual" "Linux-PAM Manual"
.\" -----------------------------------------------------------------
.\" * Define some portability stuff
.\" -----------------------------------------------------------------
.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.\" http://bugs.debian.org/507673
.\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html
.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.ie \n(.g .ds Aq \(aq
.el       .ds Aq '
.\" -----------------------------------------------------------------
.\" * set default formatting
.\" -----------------------------------------------------------------
.\" disable hyphenation
.nh
.\" disable justification (adjust text to left margin only)
.ad l
.\" -----------------------------------------------------------------
.\" * MAIN CONTENT STARTS HERE *
.\" -----------------------------------------------------------------
.SH "NAME"
pam_set_data \- set module internal data
.SH "SYNOPSIS"
.sp
.ft B
.nf
#include <security/pam_modules\&.h>
.fi
.ft
.HP \w'int\ pam_set_data('u
.BI "int pam_set_data(pam_handle_t\ *" "pamh" ", const\ char\ *" "module_data_name" ", void\ *" "data" ", void\ " "(*cleanup)(pam_handle_t\ *pamh,\ void\ *data,\ int\ error_status)" ");"
.SH "DESCRIPTION"
.PP
The
\fBpam_set_data\fR
function associates a pointer to an object with the (hopefully) unique string
\fImodule_data_name\fR
in the PAM context specified by the
\fIpamh\fR
argument\&.
.PP
PAM modules may be dynamically loadable objects\&. In general such files should not contain
\fIstatic\fR
variables\&. This function and its counterpart
\fBpam_get_data\fR(3), provide a mechanism for a module to associate some data with the handle
\fIpamh\fR\&. Typically a module will call the
\fBpam_set_data\fR
function to register some data under a (hopefully) unique
\fImodule_data_name\fR\&. The data is available for use by other modules too but
\fInot\fR
by an application\&. Since this functions stores only a pointer to the
\fIdata\fR, the module should not modify or free the content of it\&.
.PP
The function
\fBcleanup()\fR
is associated with the
\fIdata\fR
and, if non\-NULL, it is called when this data is over\-written or following a call to
\fBpam_end\fR(3)\&.
.PP
The
\fIerror_status\fR
argument is used to indicate to the module the sort of action it is to take in cleaning this data item\&. As an example, Kerberos creates a ticket file during the authentication phase, this file might be associated with a data item\&. When
\fBpam_end\fR(3)
is called by the module, the
\fIerror_status\fR
carries the return value of the
\fBpam_authenticate\fR(3)
or other
\fIlibpam\fR
function as appropriate\&. Based on this value the Kerberos module may choose to delete the ticket file (\fIauthentication failure\fR) or leave it in place\&.
.PP
The
\fIerror_status\fR
may have been logically OR\*(Aqd with either of the following two values:
.PP
PAM_DATA_REPLACE
.RS 4
When a data item is being replaced (through a second call to
\fBpam_set_data\fR) this mask is used\&. Otherwise, the call is assumed to be from
\fBpam_end\fR(3)\&.
.RE
.PP
PAM_DATA_SILENT
.RS 4
Which indicates that the process would prefer to perform the
\fBcleanup()\fR
quietly\&. That is, discourages logging/messages to the user\&.
.RE
.SH "RETURN VALUES"
.PP
PAM_BUF_ERR
.RS 4
Memory buffer error\&.
.RE
.PP
PAM_SUCCESS
.RS 4
Data was successful stored\&.
.RE
.PP
PAM_SYSTEM_ERR
.RS 4
A NULL pointer was submitted as PAM handle or the function was called by an application\&.
.RE
.SH "SEE ALSO"
.PP
\fBpam_end\fR(3),
\fBpam_get_data\fR(3),
\fBpam_strerror\fR(3)