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<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE reference PUBLIC "-//OASIS//DTD DocBook V4.4//EN"
"http://www.oasis-open.org/docbook/xml/4.4/docbookx.dtd">
<reference>
<title>GssProxy Manual pages</title>
<refentry>
<refentryinfo>
<productname>GSS Proxy</productname>
<orgname>GSS-Proxy - http://fedorahosted.org/gss-proxy</orgname>
</refentryinfo>
<refmeta>
<refentrytitle>gssproxy.conf</refentrytitle>
<manvolnum>5</manvolnum>
</refmeta>
<refnamediv id='name'>
<refname>gssproxy.conf</refname>
<refpurpose>GssProxy Daemon Configuration file</refpurpose>
</refnamediv>
<refsect1 id='description'>
<title>DESCRIPTION</title>
<para>
Optional configuration directives for the gssproxy daemon.
</para>
<para>
GSS-Proxy conf files are classic ini-style configuration files.
Each option consist of a key = value pair.
Any characters behind '#' will be treated as comments and will be ignored.
Boolean parameters accept "1", "true", "yes" and "on" as
positive values. All other values will be considered as negative
values.
</para>
<para>
GSS-Proxy conf files must either be named "gssproxy.conf", or be
of the form "##-foo.conf" (that is, start with two numbers
followed by a dash, and end in ".conf"). Files not conforming to
this will be ignored unless specifically requested through command
line parameters. Within a single file, any duplicate values or
sections will be merged. Across multiple files, duplicates will
generate a warning, and the first value encountered will take
precedence (i.e., there is no merging).
</para>
</refsect1>
<refsect1 id='sections'>
<title>SECTIONS</title>
<para>
A section in a GSS-Proxy conf file is identified by the sectionname in square brackets ([sectionname]).
</para>
<para>
There is one special section for global gssproxy settings, called
[gssproxy].
</para>
<para>
Services such as nfs, apache, ssh, etc. are represented by
sections like [service/nfs], [service/apache], etc. and are
identified by the "euid" setting (see below).
</para>
</refsect1>
<refsect1 id='substitutions'>
<title>VARIABLE SUBSTITUTIONS</title>
<para>
String parameters may contain substitution patterns. This allows gssproxy to deal with patterns for
the storage location of keytabs or credential caches easier.
</para>
<para>
The supported patterns are:
</para>
<variablelist>
<varlistentry>
<term>%U</term>
<listitem><para>substitutes to the user's numeric uid (e.g. 123)</para></listitem>
</varlistentry>
<varlistentry>
<term>%u</term>
<listitem><para>substitutes to the user's username (e.g. john).</para></listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1 id='options'>
<title>OPTIONS</title>
<para>
gssproxy supports the following options:
<variablelist>
<varlistentry>
<term>allow_any_uid (boolean)</term>
<listitem>
<para>Allow any process of any user to use this service.</para>
<para>Note that absent a custom socket option this
option may cause a service definition to mask
access to following services. To avoid issues
change the order of services in your
configuration file so that services with
allow_any_uid enabled are listed last, or define
a custom socket for other services.</para>
<para>Default: false</para>
</listitem>
</varlistentry>
<varlistentry>
<term>allow_protocol_transition (boolean)</term>
<listitem>
<para>Allow clients to request a ticket to self for an arbitrary user.</para>
<para>This option controls whether s4u2self requests are allowed for the
requesting client. The configured keytab is used as the service
identity for which a ticket is requested. The KDC still needs to allow
the operation for it to succeed.</para>
<para>Default: false</para>
</listitem>
</varlistentry>
<varlistentry>
<term>allow_constrained_delegation (boolean)</term>
<listitem>
<para>Allow clients to request a ticket to another service using an
evidence ticket.</para>
<para>This option controls whether s4u2proxy requests are allowed for
the requesting client. The KDC still needs to allow the operation
for it to succeed.</para>
<para>Default: false</para>
</listitem>
</varlistentry>
<varlistentry>
<term>allow_client_ccache_sync (boolean)</term>
<listitem>
<para>Allow clients to request credentials to be sent back for better
caching.</para>
<para>This option allows the proxy, in certain circumstances, to send back
an additional option in the response structure of certain calls when
it determines that a new ticket may have been added to the internal
ccache. Clients can then replace their (encrypted) copy with the
updated ccache.</para>
<para>Default: false</para>
</listitem>
</varlistentry>
<varlistentry>
<term>cred_store (string)</term>
<listitem>
<para>This parameter allows one to control in which way gssproxy should use the cred_store interface provided by GSSAPI. The parameter can be defined multiple times per service.</para>
<para>The syntax of the cred_store parameter is as
follows:
<![CDATA[cred_store = <cred_store_option>:<cred_store_value>]]></para>
<para>Currently this interface supports the following
options:</para>
<variablelist>
<varlistentry>
<term>keytab</term>
<listitem><para>Defines the keytab the service should use. Example: cred_store = keytab:/path/to/keytab</para></listitem>
</varlistentry>
<varlistentry>
<term>client_keytab</term>
<listitem><para>Defines a client keytab the service should use. Example: cred_store = client_keytab:/path/to/client_keytab.</para></listitem>
</varlistentry>
<varlistentry>
<term>ccache</term>
<listitem><para>Defines a credential cache the service should use. Example: cred_store = ccache:/path/to/ccache.</para></listitem>
</varlistentry>
</variablelist>
<para>Notably the client_keytab and the ccache setting
typically are used with variable substitution
placeholders (see above). For example:</para>
<programlisting>
<userinput moreinfo="none">cred_store = keytab:/etc/krb5.keytab</userinput>
<userinput moreinfo="none">cred_store = ccache:FILE:/var/lib/gssproxy/krb5cc_%U</userinput>
<userinput moreinfo="none">cred_store = client_keytab:/var/lib/gssproxy/%U.keytab</userinput>
</programlisting>
<para>Default: cred_store = </para>
</listitem>
</varlistentry>
<varlistentry>
<term>cred_usage (string)</term>
<listitem>
<para>Allow one to restrict the kind of operations permitted for this service.</para>
<para>The allowed options are: initiate, accept, both</para>
<para>Default: cred_usage = both </para>
</listitem>
</varlistentry>
<varlistentry>
<term>debug (boolean)</term>
<listitem>
<para>
Enable debugging to syslog. Setting to true is
identical to setting debug_level to 1.
</para>
<para>Default: debug = false</para>
</listitem>
</varlistentry>
<varlistentry>
<term>debug_level (integer)</term>
<listitem>
<para>
Detail level at which to log debugging messages.
0 corresponds to no logging, while 1 turns on
basic debug logging. Level 2 increases verbosity,
including more detailed credential verification.
</para>
<para>
At level 3 and above, KRB5_TRACE output is logged.
If KRB5_TRACE was already set in the execution
environment, trace output is sent to its value
instead. Refer to docs/KRB5_TRACE.md for more information.
</para>
<para>Default: 1 if debug is true, otherwise 0</para>
</listitem>
</varlistentry>
<varlistentry>
<term>enforce_flags (string)</term>
<listitem>
<para>
A list of GSS Request Flags that are added
unconditionally to every context initialization
call.
Flags can only be added to the list or removed
from the list by prepending a +/- sign to the
flag name or value.
</para>
<para>
Recognized flag names: DELEGATE, MUTUAL_AUTH,
REPLAY_DETECT, SEQUENCE, CONFIDENTIALITY,
INTEGRITY, ANONYMOUS
</para>
<para>Examples:
<programlisting>
<userinput moreinfo="none">enforce_flags = +REPLAY_DETECT</userinput>
<userinput moreinfo="none">enforce_flags = -0x0001</userinput>
</programlisting>
</para>
<para>Default: enforce_flags =</para>
</listitem>
</varlistentry>
<varlistentry>
<term>euid (integer or string)</term>
<listitem>
<para>Either the numeric (e.g., 48) or symbolic (e.g.,
apache) effective uid of a running process,
required to identify a service.</para>
<para>The "euid" parameter is imperative, any section
without it will be discarded.</para>
<para>Default: euid =</para>
</listitem>
</varlistentry>
<varlistentry>
<term>filter_flags (string)</term>
<listitem>
<para>
A list of GSS Request Flags that are filtered
unconditionally from every context initialization
call.
Flags can only be added to the list or removed
from the list by prepending a +/- sign to the
flag name or value.
</para>
<para>
NOTE: Because often gssproxy is used to withhold
access to credentials the Delegate Flag is filtered
by default. To allow a service to delegate
credentials use the first example below.
</para>
<para>
Recognized flag names: DELEGATE, MUTUAL_AUTH,
REPLAY_DETECT, SEQUENCE, CONFIDENTIALITY,
INTEGRITY, ANONYMOUS
</para>
<para>Examples:
<programlisting>
<userinput moreinfo="none">filter_flags = -DELEGATE</userinput>
<userinput moreinfo="none">filter_flags = -0x0001 +ANONYMOUS</userinput>
</programlisting>
</para>
<para>Default: filter_flags = +DELEGATE</para>
</listitem>
</varlistentry>
<varlistentry>
<term>impersonate (boolean)</term>
<listitem>
<para>Use impersonation (s4u2self + s4u2proxy) to obtain credentials</para>
<para>Default: impersonate = false</para>
</listitem>
</varlistentry>
<varlistentry>
<term>kernel_nfsd (boolean)</term>
<listitem>
<para>Boolean flag that allows the Linux kernel to check if gssproxy is running (via <filename>/proc/net/rpc/use-gss-proxy</filename>).</para>
<para>Default: kernel_nfsd = false</para>
</listitem>
</varlistentry>
<varlistentry>
<term>krb5_principal (string)</term>
<listitem>
<para>
The krb5 principal to be used preferred for this
service, if one isn't requested by the
application. Note that this does not enforce use
of this specific name; it only sets a default.
</para>
<para>Default: krb5_principal = </para>
</listitem>
</varlistentry>
<varlistentry>
<term>mechs (string)</term>
<listitem>
<para>Currently only <parameter>krb5</parameter> is supported.</para>
<para>The "mechs" parameter is imperative, any section
without it will be discarded.</para>
<para>Default: mechs = </para>
</listitem>
</varlistentry>
<varlistentry>
<term>min_lifetime (integer)</term>
<listitem>
<para>Minimum lifetime of a cached credential, in seconds.</para>
<para>If non-zero, when gssproxy is deciding whether to use
a cached credential, it will compare the lifetime of the
cached credential to this value. If the lifetime of the
cached credential is lower, gssproxy will treat the cached
credential as expired and will attempt to obtain a new
credential.
</para>
<para>Default: min_lifetime = 15</para>
</listitem>
</varlistentry>
<varlistentry>
<term>program (string)</term>
<listitem>
<para>If specified, this service will only match when
the program being run is the specified string.
</para>
<para>Programs are assumed to be specified as
canonical paths (i.e., no relative paths, no
symlinks). Additionally, the '|' character is
reserved for future use and therefore forbidden.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term>run_as_user (string)</term>
<listitem>
<para>The name of the user gssproxy will drop privileges to.</para>
<para>This option is only available in the global section.</para>
<para>Default: run_as_user = </para>
</listitem>
</varlistentry>
<varlistentry>
<term>selinux_context (string)</term>
<listitem>
<para>This option is deprecated. Use a custom socket
or euid instead.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term>socket (string)</term>
<listitem>
<para>This parameter allows one to create a per-service socket file over which gssproxy client and server components communicate.
</para>
<para>When this parameter is not set, gssproxy will
use a compiled-in default.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>syslog_status (boolean)</term>
<listitem>
<para>Enable per-call debugging output to the syslog.
This may be useful for investigating problems in
applications using gssproxy.</para>
<para>Default: syslog_status = false</para>
</listitem>
</varlistentry>
<varlistentry>
<term>trusted (boolean)</term>
<listitem><para>Defines whether this service is considered trusted. Use with caution, this enables impersonation.</para>
<para>Default: trusted = false</para>
</listitem>
</varlistentry>
<varlistentry>
<term>worker threads (integer)</term>
<listitem>
<para>Defines the amount of worker threads gssproxy will create at startup.</para>
<para>Default: worker threads = </para>
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect1>
<refsect1>
<title>SEE ALSO</title>
<para>
<citerefentry>
<refentrytitle>gssproxy</refentrytitle><manvolnum>8</manvolnum>
</citerefentry> and
<citerefentry>
<refentrytitle>gssproxy-mech</refentrytitle><manvolnum>8</manvolnum>
</citerefentry>.
</para>
</refsect1>
</refentry>
</reference>
|
