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<html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><title>Chapter 4.  Security issues of Linux-PAM</title><meta name="generator" content="DocBook XSL Stylesheets Vsnapshot"><link rel="home" href="Linux-PAM_ADG.html" title="The Linux-PAM Application Developers' Guide"><link rel="up" href="Linux-PAM_ADG.html" title="The Linux-PAM Application Developers' Guide"><link rel="prev" href="adg-interface-programming-notes.html" title="3.3. Programming notes"><link rel="next" href="adg-security-library-calls.html" title="4.1. Care about standard library calls"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">Chapter 4.  Security issues of <span class="emphasis"><em>Linux-PAM</em></span> </th></tr><tr><td width="20%" align="left"><a accesskey="p" href="adg-interface-programming-notes.html">Prev</a> </td><th width="60%" align="center"> </th><td width="20%" align="right"> <a accesskey="n" href="adg-security-library-calls.html">Next</a></td></tr></table><hr></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="adg-security"></a>Chapter 4.  Security issues of <span class="emphasis"><em>Linux-PAM</em></span> </h1></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl class="toc"><dt><span class="section"><a href="adg-security-library-calls.html">4.1. Care about standard library calls</a></span></dt><dt><span class="section"><a href="adg-security-service-name.html">4.2. Choice of a service name</a></span></dt><dt><span class="section"><a href="adg-security-conv-function.html">4.3. The conversation function</a></span></dt><dt><span class="section"><a href="adg-security-user-identity.html">4.4. The identity of the user</a></span></dt><dt><span class="section"><a href="adg-security-resources.html">4.5. Sufficient resources</a></span></dt></dl></div><p> PAM, from the perspective of an application, is a convenient API for authenticating users. PAM modules generally have no increased privilege over that possessed by the application that is making use of it. For this reason, the application must take ultimate responsibility for protecting the environment in which PAM operates. </p><p> A poorly (or maliciously) written application can defeat any <span class="emphasis"><em>Linux-PAM</em></span> module's authentication mechanisms by simply ignoring it's return values. It is the applications task and responsibility to grant privileges and access to services. The <span class="emphasis"><em>Linux-PAM</em></span> library simply assumes the responsibility of <span class="emphasis"><em>authenticating</em></span> the user; ascertaining that the user <span class="emphasis"><em>is</em></span> who they say they are. Care should be taken to anticipate all of the documented behavior of the <span class="emphasis"><em>Linux-PAM</em></span> library functions. A failure to do this will most certainly lead to a future security breach. </p></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="adg-interface-programming-notes.html">Prev</a> </td><td width="20%" align="center"> </td><td width="40%" align="right"> <a accesskey="n" href="adg-security-library-calls.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">3.3. Programming notes </td><td width="20%" align="center"><a accesskey="h" href="Linux-PAM_ADG.html">Home</a></td><td width="40%" align="right" valign="top"> 4.1. Care about standard library calls</td></tr></table></div></body></html>