path: root/modules/pam_tally/pam_tally.8.xml

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<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
	"http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd">

<refentry id="pam_tally">

  <refmeta>
    <refentrytitle>pam_tally</refentrytitle>
    <manvolnum>8</manvolnum>
    <refmiscinfo class="sectdesc">Linux-PAM Manual</refmiscinfo>
  </refmeta>

  <refnamediv id="pam_tally-name">
    <refname>pam_tally</refname>
    <refpurpose>The login counter (tallying) module</refpurpose>
  </refnamediv>

  <refsynopsisdiv>
    <cmdsynopsis id="pam_tally-cmdsynopsis1">
      <command>pam_tally.so</command>
      <arg choice="opt">
	file=<replaceable>/path/to/counter</replaceable>
      </arg>
      <arg choice="opt">
        onerr=[<replaceable>fail</replaceable>|<replaceable>succeed</replaceable>]
      </arg>
      <arg choice="opt">
        magic_root
      </arg>
      <arg choice="opt">
        even_deny_root_account
      </arg>
      <arg choice="opt">
        deny=<replaceable>n</replaceable>
      </arg>
      <arg choice="opt">
        lock_time=<replaceable>n</replaceable>
      </arg>
      <arg choice="opt">
        unlock_time=<replaceable>n</replaceable>
      </arg>
      <arg choice="opt">
        per_user
      </arg>
      <arg choice="opt">
        no_lock_time
      </arg>
      <arg choice="opt">
        no_reset
      </arg>
      <arg choice="opt">
        audit
      </arg>
      <arg choice="opt">
        silent
      </arg>
      <arg choice="opt">
        no_log_info
      </arg>
    </cmdsynopsis>
    <cmdsynopsis id="pam_tally-cmdsynopsis2">
      <command>pam_tally</command>
      <arg choice="opt">
	--file <replaceable>/path/to/counter</replaceable>
      </arg>
      <arg choice="opt">
	--user <replaceable>username</replaceable>
      </arg>
      <arg choice="opt">
	--reset[=<replaceable>n</replaceable>]
      </arg>
      <arg choice="opt">
        --quiet
      </arg>
    </cmdsynopsis>
  </refsynopsisdiv>

  <refsect1 id="pam_tally-description">

    <title>DESCRIPTION</title>

    <para>
      This module maintains a count of attempted accesses, can
      reset count on success, can deny access if too many attempts
      fail.
    </para>
    <para>
      pam_tally has several limitations, which are solved with
      pam_tally2. For this reason pam_tally is deprecated and
      will be removed in a future release.
    </para>
    <para>
      pam_tally comes in two parts:
      <emphasis remap='B'>pam_tally.so</emphasis> and
      <command>pam_tally</command>. The former is the PAM module and
      the latter, a stand-alone program. <command>pam_tally</command>
      is an (optional) application which can be used to interrogate and
      manipulate the counter file. It can display user counts, set
      individual counts, or clear all counts. Setting artificially high
      counts may be useful for blocking users without changing their
      passwords. For example, one might find it useful to clear all counts
      every midnight from a cron job. The
      <citerefentry>
	<refentrytitle>faillog</refentrytitle><manvolnum>8</manvolnum>
      </citerefentry> command can be used instead of pam_tally to to
      maintain the counter file.
    </para>
    <para>
      Normally, failed attempts to access <emphasis>root</emphasis> will
      <emphasis remap='B'>not</emphasis> cause the root account to become
      blocked, to prevent denial-of-service: if your users aren't given
      shell accounts and root may only login via <command>su</command> or
      at the machine console (not telnet/rsh, etc), this is safe.
    </para>
  </refsect1>

  <refsect1 id="pam_tally-options">

    <title>OPTIONS</title>
    <variablelist>
      <varlistentry>
        <term>
          GLOBAL OPTIONS
        </term>
        <listitem>
          <para>
            This can be used for <emphasis>auth</emphasis> and
            <emphasis>account</emphasis> module types.
          </para>
          <variablelist>
            <varlistentry>
              <term>
                <option>onerr=[<replaceable>fail</replaceable>|<replaceable>succeed</replaceable>]</option>
              </term>
              <listitem>
                <para>
                  If something weird happens (like unable to open the file),
                  return with <errorcode>PAM_SUCCESS</errorcode> if
                  <option>onerr=<replaceable>succeed</replaceable></option>
                  is given, else with the corresponding PAM error code.
                </para>
              </listitem>
            </varlistentry>
            <varlistentry>
              <term>
                <option>file=<replaceable>/path/to/counter</replaceable></option>
              </term>
              <listitem>
                <para>
                  File where to keep counts. Default is
                  <filename>/var/log/faillog</filename>.
                </para>
              </listitem>
            </varlistentry>
            <varlistentry>
              <term>
                <option>audit</option>
              </term>
              <listitem>
                <para>
                  Will log the user name into the system log if the user is not found.
                </para>
              </listitem>
            </varlistentry>
            <varlistentry>
              <term>
                <option>silent</option>
              </term>
              <listitem>
                <para>
                  Don't print informative messages.
                </para>
              </listitem>
            </varlistentry>
            <varlistentry>
              <term>
                <option>no_log_info</option>
              </term>
              <listitem>
                <para>
                  Don't log informative messages via <citerefentry><refentrytitle>syslog</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
                </para>
              </listitem>
            </varlistentry>
          </variablelist>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>
          AUTH OPTIONS
        </term>
        <listitem>
          <para>
            Authentication phase first checks if user should be denied
            access and if not it increments attempted login counter. Then
            on call to <citerefentry>
	      <refentrytitle>pam_setcred</refentrytitle><manvolnum>3</manvolnum>
            </citerefentry> it resets the attempts counter.
          </para>
          <variablelist>
            <varlistentry>
              <term>
                <option>deny=<replaceable>n</replaceable></option>
              </term>
              <listitem>
                <para>
                  Deny access if tally for this user exceeds
                  <replaceable>n</replaceable>.
                </para>
              </listitem>
            </varlistentry>
            <varlistentry>
              <term>
                <option>lock_time=<replaceable>n</replaceable></option>
              </term>
              <listitem>
                <para>
                  Always deny for <replaceable>n</replaceable> seconds
                  after failed attempt.
                </para>
              </listitem>
            </varlistentry>
            <varlistentry>
              <term>
                <option>unlock_time=<replaceable>n</replaceable></option>
              </term>
              <listitem>
                <para>
                  Allow access after <replaceable>n</replaceable> seconds
                  after failed attempt. If this option is used the user will
                  be locked out for the specified amount of time after he
                  exceeded his maximum allowed attempts. Otherwise the
                  account is locked until the lock is removed by a manual
                  intervention of the system administrator.
                </para>
              </listitem>
            </varlistentry>
            <varlistentry>
              <term>
                <option>magic_root</option>
              </term>
              <listitem>
                <para>
                  If the module is invoked by a user with uid=0 the
                  counter is not incremented. The sysadmin should use this
                  for user launched services, like <command>su</command>,
                  otherwise this argument should be omitted.
                </para>
              </listitem>
            </varlistentry>
            <varlistentry>
              <term>
                <option>no_lock_time</option>
              </term>
              <listitem>
                <para>
                  Do not use the .fail_locktime field in
                  <filename>/var/log/faillog</filename> for this user.
                </para>
              </listitem>
            </varlistentry>
            <varlistentry>
              <term>
                <option>no_reset</option>
              </term>
              <listitem>
                <para>
                  Don't reset count on successful entry, only decrement.
                </para>
              </listitem>
            </varlistentry>
            <varlistentry>
              <term>
                <option>even_deny_root_account</option>
              </term>
              <listitem>
                <para>
                  Root account can become unavailable.
                </para>
              </listitem>
            </varlistentry>
            <varlistentry>
              <term>
                <option>per_user</option>
              </term>
              <listitem>
                <para>
                  If <filename>/var/log/faillog</filename> contains a non-zero
                  .fail_max/.fail_locktime field for this user then use it
                  instead of <option>deny=<replaceable>n</replaceable></option>/
                  <option>lock_time=<replaceable>n</replaceable></option> parameter.
                </para>
              </listitem>
            </varlistentry>
            <varlistentry>
              <term>
                <option>no_lock_time</option>
              </term>
              <listitem>
                <para>
                  Don't use .fail_locktime filed in
                  <filename>/var/log/faillog</filename> for this user.
                </para>
              </listitem>
            </varlistentry>

          </variablelist>
        </listitem>
      </varlistentry>


      <varlistentry>
        <term>
          ACCOUNT OPTIONS
        </term>
        <listitem>
          <para>
            Account phase resets attempts counter if the user is
            <emphasis remap='B'>not</emphasis> magic root.
            This phase can be used optionally for services which don't call
            <citerefentry>
	      <refentrytitle>pam_setcred</refentrytitle><manvolnum>3</manvolnum>
            </citerefentry> correctly or if the reset should be done regardless
            of the failure of the account phase of other modules.
          </para>
          <variablelist>
            <varlistentry>
              <term>
                <option>magic_root</option>
              </term>
              <listitem>
                <para>
                  If the module is invoked by a user with uid=0 the
                  counter is not incremented. The sysadmin should use this
                  for user launched services, like <command>su</command>,
                  otherwise this argument should be omitted.
                </para>
              </listitem>
            </varlistentry>
            <varlistentry>
              <term>
                <option>no_reset</option>
              </term>
              <listitem>
                <para>
                  Don't reset count on successful entry, only decrement.
                </para>
              </listitem>
            </varlistentry>
          </variablelist>
        </listitem>
      </varlistentry>
    </variablelist>
  </refsect1>

  <refsect1 id="pam_tally-types">
    <title>MODULE TYPES PROVIDED</title>
    <para>
      The <option>auth</option> and <option>account</option>
      module types are provided.
    </para>
  </refsect1>

  <refsect1 id='pam_tally-return_values'>
    <title>RETURN VALUES</title>
    <variablelist>
      <varlistentry>
        <term>PAM_AUTH_ERR</term>
        <listitem>
          <para>
            A invalid option was given, the module was not able
            to retrieve the user name, no valid counter file
            was found, or too many failed logins.
          </para>
        </listitem>
      </varlistentry>
      <varlistentry>
        <term>PAM_SUCCESS</term>
        <listitem>
          <para>
            Everything was successful.
          </para>
        </listitem>
      </varlistentry>
      <varlistentry>
        <term>PAM_USER_UNKNOWN</term>
        <listitem>
          <para>
	    User not known.
          </para>
        </listitem>
      </varlistentry>
    </variablelist>
  </refsect1>

  <refsect1 id='pam_tally-examples'>
    <title>EXAMPLES</title>
    <para>
      Add the following line to <filename>/etc/pam.d/login</filename> to
      lock the account after too many failed logins. The number of
      allowed fails is specified by <filename>/var/log/faillog</filename>
      and needs to be set with pam_tally or <citerefentry>
	<refentrytitle>faillog</refentrytitle><manvolnum>8</manvolnum>
      </citerefentry> before.
    </para>
    <programlisting>
auth     required       pam_securetty.so
auth     required       pam_tally.so per_user
auth     required       pam_env.so
auth     required       pam_unix.so
auth     required       pam_nologin.so
account  required       pam_unix.so
password required       pam_unix.so
session  required       pam_limits.so
session  required       pam_unix.so
session  required       pam_lastlog.so nowtmp
session  optional       pam_mail.so standard
    </programlisting>
  </refsect1>

  <refsect1 id="pam_tally-files">
    <title>FILES</title>
    <variablelist>
      <varlistentry>
        <term><filename>/var/log/faillog</filename></term>
        <listitem>
          <para>failure logging file</para>
        </listitem>
      </varlistentry>
    </variablelist>
  </refsect1>

  <refsect1 id='pam_tally-see_also'>
    <title>SEE ALSO</title>
    <para>
      <citerefentry>
	<refentrytitle>faillog</refentrytitle><manvolnum>8</manvolnum>
      </citerefentry>,
      <citerefentry>
	<refentrytitle>pam.conf</refentrytitle><manvolnum>5</manvolnum>
      </citerefentry>,
      <citerefentry>
	<refentrytitle>pam.d</refentrytitle><manvolnum>5</manvolnum>
      </citerefentry>,
      <citerefentry>
	<refentrytitle>pam</refentrytitle><manvolnum>8</manvolnum>
      </citerefentry>
    </para>
  </refsect1>

  <refsect1 id='pam_tally-author'>
    <title>AUTHOR</title>
      <para>
        pam_tally was written by Tim Baverstock and Tomas Mraz.
      </para>
  </refsect1>

</refentry>