sssd-sudo.5.xml revision b24712874c686977465a551a3129133cec884584
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<!DOCTYPE reference PUBLIC "-//OASIS//DTD DocBook V4.4//EN"
<reference>
<title>SSSD Manual pages</title>
<refentry>
<refmeta>
<refentrytitle>sssd-sudo</refentrytitle>
<manvolnum>5</manvolnum>
<refmiscinfo class="manual">File Formats and Conventions</refmiscinfo>
</refmeta>
<refnamediv id='name'>
<refname>sssd-sudo</refname>
<refpurpose>the configuration file for SSSD</refpurpose>
</refnamediv>
<refsect1 id='description'>
<title>DESCRIPTION</title>
<para>
This manual page describes how to configure
<citerefentry>
<refentrytitle>sudo</refentrytitle>
<manvolnum>8</manvolnum>
</citerefentry> to work with
<citerefentry>
<refentrytitle>sssd</refentrytitle>
<manvolnum>8</manvolnum>
</citerefentry> and how SSSD caches sudo rules.
</para>
</refsect1>
<refsect1 id='sudo'>
<title>Configuring sudo to cooperate with SSSD</title>
<para>
To enable SSSD as a source for sudo rules, add
<emphasis>sss</emphasis> to the <emphasis>sudoers</emphasis> entry
in
<citerefentry>
<manvolnum>5</manvolnum>
</citerefentry>.
</para>
<para>
For example, to configure sudo to first lookup rules in the standard
<citerefentry>
<refentrytitle>sudoers</refentrytitle>
<manvolnum>5</manvolnum>
</citerefentry> file (which should contain rules that apply to
local users) and then in SSSD, the nsswitch.conf file should contain
the following line:
</para>
<para>
<programlisting>
sudoers: files sss
</programlisting>
</para>
<para>
More information about configuring the sudoers search order from the
nsswitch.conf file as well as information about the LDAP schema that
is used to store sudo rules in the directory can be found in
<citerefentry>
<manvolnum>5</manvolnum>
</citerefentry>.
</para>
</refsect1>
<refsect1 id='sssd'>
<title>Configuring SSSD to fetch sudo rules</title>
<para>
The following example shows how to configure SSSD to download sudo
rules from an LDAP server.
</para>
<para>
<programlisting>
[sssd]
config_file_version = 2
services = nss, pam, sudo
domains = EXAMPLE
id_provider = ldap
sudo_provider = ldap
ldap_uri = ldap://example.com
ldap_sudo_search_base = ou=sudoers,dc=example,dc=com
</programlisting>
</para>
<para>
The following example illustrates setting up SSSD to download
sudo rules from an IPA server. It is necessary to use the LDAP
provider and set appropriate connection parameters to authenticate
correctly against the IPA server, because SSSD does not have native
support of IPA provider for sudo yet.
</para>
<para>
<programlisting>
[sssd]
config_file_version = 2
services = nss, pam, sudo
domains = EXAMPLE
id_provider = ipa
ipa_domain = example.com
ipa_server = ipa.example.com
sudo_provider = ldap
ldap_uri = ldap://ipa.example.com
ldap_sudo_search_base = ou=sudoers,dc=example,dc=com
ldap_sasl_mech = GSSAPI
ldap_sasl_authid = host/hostname.example.com
ldap_sasl_realm = EXAMPLE.COM
krb5_server = ipa.example.com
</programlisting>
</para>
</refsect1>
<refsect1 id='cache'>
<title>The SUDO rule caching mechanism</title>
<para>
The biggest challenge, when developing sudo support in SSSD, was to
ensure that running sudo with SSSD as the data source provides the
same user experience and is as fast as sudo but keeps providing
the most current set of rules as possible. To satisfy these
requirements, SSSD uses three kinds of updates. They are referred to
as full refresh, smart refresh and rules refresh.
</para>
<para>
The <emphasis>smart refresh</emphasis> periodically downloads rules
that are new or were modified after the last update. Its primary
goal is to keep the database growing by fetching only small
increments that do not generate large amounts of network traffic.
</para>
<para>
The <emphasis>full refresh</emphasis> simply deletes all sudo rules
stored in the cache and replaces them with all rules that are stored
on the server. This is used to keep the cache consistent by removing
every rule which was deleted from the server. However, full refresh
may produce a lot of traffic and thus it should be run only
occasionally depending on the size and stability of the sudo rules.
</para>
<para>
The <emphasis>rules refresh</emphasis> ensures that we do not grant
the user more permission than defined. It is triggered each time the
user runs sudo. Rules refresh will find all rules that apply to this
user, check their expiration time and redownload them if expired.
In the case that any of these rules are missing on the server, the
SSSD will do an out of band full refresh because more rules
(that apply to other users) may have been deleted.
</para>
<para>
If enabled, SSSD will store only rules that can be applied to this
machine. This means rules that contain one of the following values
in <emphasis>sudoHost</emphasis> attribute:
</para>
<itemizedlist>
<listitem>
<para>
keyword ALL
</para>
</listitem>
<listitem>
<para>
wildcard
</para>
</listitem>
<listitem>
<para>
netgroup (in the form "+netgroup")
</para>
</listitem>
<listitem>
<para>
hostname or fully qualified domain name of this machine
</para>
</listitem>
<listitem>
<para>
one of the IP addresses of this machine
</para>
</listitem>
<listitem>
<para>
one of the IP addresses of the network
</para>
</listitem>
</itemizedlist>
<para>
There are many configuration options that can be used to adjust
the behavior. Please refer to "ldap_sudo_*" in
<citerefentry>
<refentrytitle>sssd-ldap</refentrytitle>
<manvolnum>5</manvolnum>
</citerefentry> and "sudo_*" in
<citerefentry>
<manvolnum>5</manvolnum>
</citerefentry>.
</para>
</refsect1>
</refentry>
</reference>