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diff --git a/modules/pam_namespace/namespace.conf.5.xml b/modules/pam_namespace/namespace.conf.5.xml new file mode 100644 index 0000000..a94b49e --- /dev/null +++ b/modules/pam_namespace/namespace.conf.5.xml @@ -0,0 +1,223 @@ +<?xml version="1.0" encoding='UTF-8'?> +<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN" + "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd"> + +<refentry id="namespace.conf"> + + <refmeta> + <refentrytitle>namespace.conf</refentrytitle> + <manvolnum>5</manvolnum> + <refmiscinfo class="sectdesc">Linux-PAM Manual</refmiscinfo> + </refmeta> + + <refnamediv> + <refname>namespace.conf</refname> + <refpurpose>the namespace configuration file</refpurpose> + </refnamediv> + + + <refsect1 id='namespace.conf-description'> + <title>DESCRIPTION</title> + + <para> + The <emphasis>pam_namespace.so</emphasis> module allows setup of + private namespaces with polyinstantiated directories. + Directories can be polyinstantiated based on user name + or, in the case of SELinux, user name, sensitivity level or complete security context. If an + executable script <filename>/etc/security/namespace.init</filename> + exists, it is used to initialize the namespace every time an instance + directory is set up and mounted. The script receives the polyinstantiated + directory path and the instance directory path as its arguments. + </para> + + <para> + The <filename>/etc/security/namespace.conf</filename> file specifies + which directories are polyinstantiated, how they are polyinstantiated, + how instance directories would be named, and any users for whom + polyinstantiation would not be performed. + </para> + + <para> + When someone logs in, the file <filename>namespace.conf</filename> is + scanned. Comments are marked by <emphasis>#</emphasis> characters. + Each non comment line represents one polyinstantiated + directory. The fields are separated by spaces but can be quoted by + <emphasis>"</emphasis> characters also escape + sequences <emphasis>\b</emphasis>, <emphasis>\n</emphasis>, and + <emphasis>\t</emphasis> are recognized. The fields are as follows: + </para> + + <para><replaceable>polydir</replaceable> <replaceable>instance_prefix</replaceable> <replaceable>method</replaceable> <replaceable>list_of_uids</replaceable> + </para> + + <para> + The first field, <replaceable>polydir</replaceable>, is the absolute + pathname of the directory to polyinstantiate. The special string + <emphasis>$HOME</emphasis> is replaced with the user's home directory, + and <emphasis>$USER</emphasis> with the username. This field cannot + be blank. + </para> + + <para> + The second field, <replaceable>instance_prefix</replaceable> is + the string prefix used to build the pathname for the instantiation + of <polydir>. Depending on the polyinstantiation + <replaceable>method</replaceable> it is then appended with + "instance differentiation string" to generate the final + instance directory path. This directory is created if it did not exist + already, and is then bind mounted on the <polydir> to provide an + instance of <polydir> based on the <method> column. + The special string <emphasis>$HOME</emphasis> is replaced with the + user's home directory, and <emphasis>$USER</emphasis> with the username. + This field cannot be blank. + </para> + + <para> + The third field, <replaceable>method</replaceable>, is the method + used for polyinstantiation. It can take these values; "user" + for polyinstantiation based on user name, "level" for + polyinstantiation based on process MLS level and user name, "context" for + polyinstantiation based on process security context and user name, + "tmpfs" for mounting tmpfs filesystem as an instance dir, and + "tmpdir" for creating temporary directory as an instance dir which is + removed when the user's session is closed. + Methods "context" and "level" are only available with SELinux. This + field cannot be blank. + </para> + + <para> + The fourth field, <replaceable>list_of_uids</replaceable>, is + a comma separated list of user names for whom the polyinstantiation + is not performed. If left blank, polyinstantiation will be performed + for all users. If the list is preceded with a single "~" character, + polyinstantiation is performed only for users in the list. + </para> + + <para> + The <replaceable>method</replaceable> field can contain also following + optional flags separated by <emphasis>:</emphasis> characters. + </para> + + <para><emphasis>create</emphasis>=<replaceable>mode</replaceable>,<replaceable>owner</replaceable>,<replaceable>group</replaceable> + - create the polyinstantiated directory. The mode, owner and group parameters + are optional. The default for mode is determined by umask, the default + owner is the user whose session is opened, the default group is the + primary group of the user. + </para> + + <para><emphasis>iscript</emphasis>=<replaceable>path</replaceable> + - path to the instance directory init script. The base directory for relative + paths is <filename>/etc/security/namespace.d</filename>. + </para> + + <para><emphasis>noinit</emphasis> + - instance directory init script will not be executed. + </para> + + <para><emphasis>shared</emphasis> + - the instance directories for "context" and "level" methods will not + contain the user name and will be shared among all users. + </para> + + <para><emphasis>mntopts</emphasis>=<replaceable>value</replaceable> + - value of this flag is passed to the mount call when the tmpfs mount is + done. It allows for example the specification of the maximum size of the + tmpfs instance that is created by the mount call. In addition to + options specified in the <citerefentry> + <refentrytitle>tmpfs</refentrytitle><manvolnum>5</manvolnum> + </citerefentry> manual the <emphasis>nosuid</emphasis>, + <emphasis>noexec</emphasis>, and <emphasis>nodev</emphasis> flags + can be used to respectively disable setuid bit effect, disable running + executables, and disable devices to be interpreted on the mounted + tmpfs filesystem. + </para> + + <para> + The directory where polyinstantiated instances are to be + created, must exist and must have, by default, the mode of 0000. The + requirement that the instance parent be of mode 0000 can be overridden + with the command line option <emphasis>ignore_instance_parent_mode</emphasis> + </para> + + <para> + In case of context or level polyinstantiation the SELinux context + which is used for polyinstantiation is the context used for executing + a new process as obtained by getexeccon. This context must be set + by the calling application or <filename>pam_selinux.so</filename> + module. If this context is not set the polyinstatiation will be + based just on user name. + </para> + + <para> + The "instance differentiation string" is <user name> for "user" + method and <user name>_<raw directory context> for "context" + and "level" methods. If the whole string is too long the end of it is + replaced with md5sum of itself. Also when command line option + <emphasis>gen_hash</emphasis> is used the whole string is replaced + with md5sum of itself. + </para> + + </refsect1> + + <refsect1 id="namespace.conf-examples"> + <title>EXAMPLES</title> + <para> + These are some example lines which might be specified in + <filename>/etc/security/namespace.conf</filename>. + </para> + + <literallayout> + # The following three lines will polyinstantiate /tmp, + # /var/tmp and user's home directories. /tmp and /var/tmp + # will be polyinstantiated based on the security level + # as well as user name, whereas home directory will be + # polyinstantiated based on the full security context and user name. + # Polyinstantiation will not be performed for user root + # and adm for directories /tmp and /var/tmp, whereas home + # directories will be polyinstantiated for all users. + # + # Note that instance directories do not have to reside inside + # the polyinstantiated directory. In the examples below, + # instances of /tmp will be created in /tmp-inst directory, + # where as instances of /var/tmp and users home directories + # will reside within the directories that are being + # polyinstantiated. + # + /tmp /tmp-inst/ level root,adm + /var/tmp /var/tmp/tmp-inst/ level root,adm + $HOME $HOME/$USER.inst/inst- context + </literallayout> + + <para> + For the <service>s you need polyinstantiation (login for example) + put the following line in /etc/pam.d/<service> as the last line for + session group: + </para> + + <para> + session required pam_namespace.so [arguments] + </para> + + <para> + This module also depends on pam_selinux.so setting the context. + </para> + + </refsect1> + + <refsect1 id="namespace.conf-see_also"> + <title>SEE ALSO</title> + <para> + <citerefentry><refentrytitle>pam_namespace</refentrytitle><manvolnum>8</manvolnum></citerefentry>, + <citerefentry><refentrytitle>pam.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>, + <citerefentry><refentrytitle>pam</refentrytitle><manvolnum>8</manvolnum></citerefentry> + </para> + </refsect1> + + <refsect1 id="namespace.conf-author"> + <title>AUTHORS</title> + <para> + The namespace.conf manual page was written by Janak Desai <janak@us.ibm.com>. + More features added by Tomas Mraz <tmraz@redhat.com>. + </para> + </refsect1> +</refentry> |