.gitignore | 70 A8Eq.c | 49 AA16.c | 51 AA32.c | 51 AA8.c | 51 Alloc.c | 79 - AofA8.c | 51 Array.c | 247 +++ CA8.c | 48 CmpKey.c | 49 DA16.c | 46 DA32.c | 44 DA8.c | 44 DAofA8.c | 50 DecKey.c | 49 Fill.c | 14 Flush.c | 9 GenKey.c | 74 INSTALL | 236 --- IncKey.c | 49 Key.c | 102 + Makefile.am | 64 RA16.c | 70 RA32.c | 70 RA8.c | 70 RAofA8.c | 73 RC16.c | 50 RC32.c | 54 RC8.c | 45 RHead.c | 46 RR.c | 42 RaA16.c | 51 RaA32.c | 51 RaA8.c | 51 RaAoA8.c | 51 Read.c | 244 +++ Unwrap.c | 5 WA16.c | 49 WA32.c | 49 WA8.c | 49 WAofA8.c | 49 WC16.c | 50 WC32.c | 53 WC8.c | 49 Whead.c | 64 Wrap.c | 5 Wrap.h | 4 Wraphelp.c | 5 Write.c | 151 ++ configure.ac | 28 doc/.gitignore | 5 doc/Makefile.am | 64 doc/xdmcp.xml | 3895 ++++++++++++++++++++++++++++++++++++++++++++++++++++ include/X11/Xdmcp.h | 27 54 files changed, 4812 insertions(+), 2284 deletions(-)
New commits: commit 7db29ff43eb3cdcbfe77c35ecc78c7ca3ddba595 Author: Alan Coopersmith <[email protected]> Date: Fri Oct 29 15:13:16 2010 -0700 libXdmcp 1.1.0 Signed-off-by: Alan Coopersmith <[email protected]> diff --git a/configure.ac b/configure.ac index 7585365..5de378a 100644 --- a/configure.ac +++ b/configure.ac @@ -22,7 +22,8 @@ dnl dnl Process this file with autoconf to create configure. AC_PREREQ([2.60]) -AC_INIT(libXdmcp, 1.0.3, [https://bugs.freedesktop.org/enter_bug.cgi?product=xorg],libXdmcp) +AC_INIT([libXdmcp], [1.1.0], + [https://bugs.freedesktop.org/enter_bug.cgi?product=xorg], [libXdmcp]) AM_INIT_AUTOMAKE([foreign dist-bzip2]) AM_MAINTAINER_MODE commit fef4451fa3c55dcf81e7eee7ca001c57e301a150 Author: Alan Coopersmith <[email protected]> Date: Wed Oct 27 23:01:49 2010 -0700 Remove AC_PROG_CC & AC_PROG_INSTALL that XORG_DEFAULT_OPTIONS already call Signed-off-by: Alan Coopersmith <[email protected]> diff --git a/configure.ac b/configure.ac index 576fc2d..7585365 100644 --- a/configure.ac +++ b/configure.ac @@ -38,8 +38,6 @@ XORG_WITH_XMLTO(0.0.20) XORG_WITH_FOP XORG_CHECK_SGML_DOCTOOLS(1.5) -AC_PROG_CC -AC_PROG_INSTALL AC_PROG_LN_S AC_LIBTOOL_WIN32_DLL AM_PROG_LIBTOOL commit 21c9f93bb5200dda0bfdd05b928c19829f23d646 Author: Gaetan Nadon <[email protected]> Date: Tue Aug 3 15:28:51 2010 -0400 config: require xorg-macros minimum of 1.10 for XORG_CHECK_SGML_DOCTOOLS Signed-off-by: Gaetan Nadon <[email protected]> diff --git a/configure.ac b/configure.ac index a49d9c2..576fc2d 100644 --- a/configure.ac +++ b/configure.ac @@ -28,10 +28,10 @@ AM_MAINTAINER_MODE AM_CONFIG_HEADER(config.h) -# Require xorg-macros: XORG_DEFAULT_OPTIONS +# Require xorg-macros minimum of 1.10 for HAVE_STYLESHEETS in XORG_CHECK_SGML_DOCTOOLS m4_ifndef([XORG_MACROS_VERSION], - [m4_fatal([must install xorg-macros 1.3 or later before running autoconf/autogen])]) -XORG_MACROS_VERSION(1.3) + [m4_fatal([must install xorg-macros 1.10 or later before running autoconf/autogen])]) +XORG_MACROS_VERSION(1.10) XORG_DEFAULT_OPTIONS XORG_ENABLE_DOCS XORG_WITH_XMLTO(0.0.20) commit adaf75c9aac6ca77b26379cc5e451728d9f1a78b Author: Matt Dew <[email protected]> Date: Sun Aug 1 14:23:18 2010 -0400 specs: replace troff source with docbook-xml source Signed-off-by: Gaetan Nadon <[email protected]> diff --git a/Makefile.am b/Makefile.am index fd16ccc..c3b85aa 100644 --- a/Makefile.am +++ b/Makefile.am @@ -1,3 +1,5 @@ +SUBDIRS=doc + lib_LTLIBRARIES = libXdmcp.la AM_CPPFLAGS = -I${top_srcdir}/include diff --git a/configure.ac b/configure.ac index 9582762..a49d9c2 100644 --- a/configure.ac +++ b/configure.ac @@ -33,6 +33,10 @@ m4_ifndef([XORG_MACROS_VERSION], [m4_fatal([must install xorg-macros 1.3 or later before running autoconf/autogen])]) XORG_MACROS_VERSION(1.3) XORG_DEFAULT_OPTIONS +XORG_ENABLE_DOCS +XORG_WITH_XMLTO(0.0.20) +XORG_WITH_FOP +XORG_CHECK_SGML_DOCTOOLS(1.5) AC_PROG_CC AC_PROG_INSTALL @@ -61,4 +65,5 @@ XORG_WITH_LINT XORG_LINT_LIBRARY([Xdmcp]) AC_OUTPUT([Makefile + doc/Makefile xdmcp.pc]) diff --git a/doc/.gitignore b/doc/.gitignore new file mode 100644 index 0000000..09b6a89 --- /dev/null +++ b/doc/.gitignore @@ -0,0 +1,5 @@ +*.html +*.ps +*.pdf +*.txt +*.css diff --git a/doc/Makefile.am b/doc/Makefile.am new file mode 100644 index 0000000..c2aa671 --- /dev/null +++ b/doc/Makefile.am @@ -0,0 +1,64 @@ +# +# Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved. +# +# Permission is hereby granted, free of charge, to any person obtaining a +# copy of this software and associated documentation files (the "Software"), +# to deal in the Software without restriction, including without limitation +# the rights to use, copy, modify, merge, publish, distribute, sublicense, +# and/or sell copies of the Software, and to permit persons to whom the +# Software is furnished to do so, subject to the following conditions: +# +# The above copyright notice and this permission notice (including the next +# paragraph) shall be included in all copies or substantial portions of the +# Software. +# +# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL +# THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING +# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER +# DEALINGS IN THE SOFTWARE. +# + +if ENABLE_DOCS +doc_sources = xdmcp.xml +dist_doc_DATA = $(doc_sources) + +if HAVE_XMLTO +doc_DATA = $(doc_sources:.xml=.html) + +if HAVE_FOP +doc_DATA += $(doc_sources:.xml=.ps) $(doc_sources:.xml=.pdf) +endif + +if HAVE_XMLTO_TEXT +doc_DATA += $(doc_sources:.xml=.txt) +endif + +if HAVE_STYLESHEETS +XMLTO_FLAGS = -m $(XSL_STYLESHEET) + +doc_DATA += xorg.css +xorg.css: $(STYLESHEET_SRCDIR)/xorg.css + $(AM_V_GEN)cp -pf $(STYLESHEET_SRCDIR)/xorg.css $@ +endif + +CLEANFILES = $(doc_DATA) + +SUFFIXES = .xml .ps .pdf .txt .html + +.xml.txt: + $(AM_V_GEN)$(XMLTO) $(XMLTO_FLAGS) txt $< + +.xml.html: + $(AM_V_GEN)$(XMLTO) $(XMLTO_FLAGS) xhtml-nochunks $< + +.xml.pdf: + $(AM_V_GEN)$(XMLTO) $(XMLTO_FLAGS) --with-fop pdf $< + +.xml.ps: + $(AM_V_GEN)$(XMLTO) $(XMLTO_FLAGS) --with-fop ps $< + +endif HAVE_XMLTO +endif ENABLE_DOCS diff --git a/doc/xdmcp.xml b/doc/xdmcp.xml new file mode 100644 index 0000000..22bccc6 --- /dev/null +++ b/doc/xdmcp.xml @@ -0,0 +1,3895 @@ +<?xml version="1.0" encoding="UTF-8" ?> +<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN" + "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd";> + +<book id="xdmcp"> + +<bookinfo> + <title>X Display Manager Control Protocol</title> + <subtitle>X.Org Standard</subtitle> + <releaseinfo>Version 1.1</releaseinfo> + <authorgroup> + <author> + <firstname>Keith</firstname><surname>Packard</surname> + <affiliation><orgname> +X Consortium, +Laboratory for Computer Science, +Massachusetts Institute of Technology + </orgname></affiliation> + </author> + </authorgroup> + + <copyright><year>1989</year><holder>The Open Group</holder></copyright> + <copyright><year>2004</year><holder>The Open Group</holder></copyright> + <productnumber>X Version 11, Release 6.8</productnumber> + +<legalnotice> + + + +<para> +Permission is hereby granted, free of charge, to any person obtaining a copy +of this software and associated documentation files (the "Software"), to deal +in the Software without restriction, including without limitation the rights +to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +copies of the Software, and to permit persons to whom the Software is +furnished to do so, subject to the following conditions: +</para> +<para> +The above copyright notice and this permission notice shall be included in +all copies or substantial portions of the Software. +</para> +<para> +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN +AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN +CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. +</para> +<para> +Except as contained in this notice, the name of The Open Group shall not be +used in advertising or otherwise to promote the sale, use or other dealings +in this Software without prior written authorization from The Open Group. +</para> + +<para> +<emphasis remap='I'>X Window System</emphasis> is a trademark of The Open Group. +</para> +</legalnotice> +</bookinfo> + +<chapter id="TITLE"> +<title>TITLE</title> +<sect1 id="Purpose_and_Goals"> +<title>Purpose and Goals</title> +<!-- .XS --> +<!-- (SN Purpose and Goals --> +<!-- .XE --> +<para> +<!-- .LP --> +The purpose of the X Display Manager Control Protocol (XDMCP) +is to provide a uniform mechanism for an autonomous +display to request login service from a remote host. +By autonomous, we mean +the display consists of hardware and processes that are independent of any +particular host where login service is desired. (For example, the server +cannot simply be started by a +<function>fork/exec</function> +sequence on the host.) +An X terminal (screen, keyboard, mouse, processor, network interface) +is a prime example of an autonomous display. +</para> + +<para> +From the point of view of the end user, it is very important to make +autonomous displays as easy to use as traditional hardwired character +terminals. Specifically, you can typically just power on a hardwired +terminal and be greeted with a login prompt. The same should be possible +with autonomous displays. However, in a network environment with multiple +hosts, the end user may want to choose which host(s) to connect to. In an +environment with many displays and many hosts, a site administrator may want +to associate particular collections of hosts with particular displays. We +would like to support the following options: +</para> + +<itemizedlist> + <listitem> + <para> +The display has a single, fixed host to which it should connect. It should be +possible to power on the display and receive a login prompt, without user +intervention. + </para> + </listitem> + <listitem> + <para> +Any one of several hosts on a network or subnetwork may be acceptable +for accepting login from the display. +(For example, the user's file systems can be mounted onto +any such host, providing comparable environments.) It should be possible +for the display to broadcast to find such hosts and to have the display +either automatically choose a host or present the possible hosts to the +user for selection. + </para> + </listitem> + <listitem> + <para> +The display has a fixed set of hosts that it can connect to. It should be +possible for the display to have that set stored in RAM, but it should also be +possible for a site administrator to be able to maintain host sets for a +large number of displays using a centralized facility, without having to +interact (physically or electronically) with each individual display. +Particular hosts should be allowed to refuse login service, based on +whatever local criteria are desired. + </para> + </listitem> +</itemizedlist> + +<para> +The control protocol should be designed in such a way that it can be used over +a reasonable variety of communication transport layers. In fact, it is quite +desirable if every major network protocol family that supports the standard X +protocol is also capable of supporting XDMCP, because the end result of XDMCP +negotiation will be standard X protocol connections to the display. +However, because the number of displays per host may be large, +a connection-based protocol appears less desirable +than a connection-less protocol. For this reason the protocol is designed +to use datagram services with the display responsible for sequencing and +retransmission. +</para> +<para> +<!-- .LP --> +To keep the burden on displays at a minimum (because display cost is not +a factor that can be ignored), it is desirable that displays not be required +to maintain permanent state (across power cycles) for the purposes +of the control protocol, +and it is desirable to keep required state at a minimum while the +display is powered on. +</para> +<para> +<!-- .LP --> +Security is an important consideration and must be an integral part of the +design. The important security goals in the context of XDMCP are: +</para> +<itemizedlist> + <listitem> + <para> +It should be possible for the display to verify that it is communicating +with a legitimate host login service. Because the user will present +credentials (for example, password) to this service, +it is important to avoid spoof attacks. + </para> + </listitem> + <listitem> + <para> +It should be possible for the display and the login service to negotiate the +authorization mechanism to be used for the standard X protocol. + </para> + </listitem> + <listitem> + <para> +It should be possible to provide the same level of security in verifying the +login service as is provided by the negotiated authorization mechanism. + </para> + </listitem> + <listitem> + <para> +Because there are no firm standards yet in the area of security, +XDMCP must be flexible enough to accomodate a variety of security mechanisms. + </para> + </listitem> +</itemizedlist> +</sect1> + +<sect1 id="Overview_of_the_Protocol"> +<title>Overview of the Protocol</title> +<!-- .XS --> +<!-- (SN Overview of the Protocol --> +<!-- .XE --> +<para> +<!-- .LP --> +XDMCP is designed to provide authenticated access to display management +services for remote displays. A new network server, called a \fIDisplay +Manager\fP, will use XDMCP to communicate with displays to negotiate the +startup of X sessions. The protocol allows the display to authenticate the +manager. It also allows most of the configuration information to be +centralized with the manager and to ease the burden of system administration +in a large network of displays. +The essential goal is to provide plug-and-play +services similar to those provided in the familiar mainframe/terminal world. +</para> +<para> +<!-- .LP --> +Displays may be turned off by the user at any time. Any existing session +running on a display that has been turned off must be identifiable. This +is made possible by requiring a three-way handshake to start a session. If +the handshake succeeds, any existing session is terminated immediately and a +new session started. There is the problem (at least with TCP) that +connections may not be closed when the display is turned off. In most +environments, the manager should reduce this problem by periodically XSync'ing +on its own connection, perhaps every five to ten minutes, and terminating the +session if its own connection ever closes. +</para> +<para> +<!-- .LP --> +Displays should not be required to retain permanent state for purposes of +the control protocol. One solution to packets received out of sequence +would be to use monotonically increasing message identifiers in each message +to allow both sides to ignore messages that arrive out-of-sequence. For +this to work, displays would at a minimum have to increment a stable crash +count each time they are powered on and use that number as part of a +larger sequence number. But if displays cannot retain permanent state this +cannot work. Instead, the manager assumes the responsibility for permanent +state by generating unique numbers that identify a particular session and +the protocol simply ignores packets that correspond to an invalid session. +</para> +<para> +<!-- .LP --> +The Manager must not be responsible for packet reception. To prevent the +Manager from becoming stuck because of a hostile display, no portion of the +protocol requires the Manager to retransmit a packet. Part of this means +that any valid packet that the Manager does receive must be +acknowledged in some way to prevent the display from continuously resending +packets. The display can keep the protocol running as it will always know +when the Manager has received (at least one copy of) a packet. On the +Manager side, this means that any packet may be received more than once (if +the response was lost) and duplicates must be ignored. +</para> +</sect1> + +<sect1 id="Data_Types"> +<title>Data Types</title> +<!-- .XS --> +<!-- (SN Data Types --> +<!-- .XE --> +<para> +<!-- .LP --> +XDMCP packets contain several types of data. Integer values are always +stored most significant byte first in the packet ("Big Endian" order). +As XDMCP will not be used to transport large quantities of data, this +restriction will not substantially hamper the efficiency of any +implementation. Also, no padding of any sort will occur within the packets. +</para> + +<informaltable frame="none"> + <tgroup cols='3' align='left'> + <colspec colname='c1' colsep="0"/> + <colspec colname='c2' colsep="0"/> + <colspec colname='c3' colsep="0"/> + <thead> + <row> + <entry>Type Name</entry> + <entry>Length (Bytes)</entry> + <entry>Description</entry> + </row> + </thead> + <tbody> + <row rowsep="0"> + <entry>CARD8</entry> + <entry>1</entry> + <entry>A single byte unsigned integer</entry> + </row> + <row rowsep="0"> + <entry>CARD16</entry> + <entry>2</entry> + <entry>Two byte unsigned integer</entry> + </row> + <row rowsep="0"> + <entry>CARD32</entry> + <entry>4</entry> + <entry>Four byte unsigned integer</entry> + </row> + <row rowsep="0"> + <entry>ARRAY8</entry> + <entry>n+2</entry> + <entry> +This is actually a CARD16 followed by +a collection of CARD8. The value of the CARD16 +field (n) specifies the number of CARD8 values to follow + </entry> + </row> + <row rowsep="0"> + <entry>ARRAY16</entry> + <entry>2*m+1</entry> + <entry> +This is a CARD8 (m) which specifies the +number of CARD16 values to follow + </entry> + </row> + <row rowsep="0"> + <entry>ARRAY32</entry> + <entry>4*l+1</entry> + <entry> +This is a CARD8 (l) which specifies the +number of CARD32 values to follow + </entry> + </row> + <row rowsep="0"> + <entry>ARRAYofARRAY8</entry> + <entry>?</entry> + <entry> +This is a CARD8 which specifies the +number of ARRAY8 values to follow. + </entry> + </row> + </tbody> + </tgroup> +</informaltable> +</sect1> + +<sect1 id="Packet_Format"> +<title>Packet Format</title> +<!-- .XS --> +<!-- (SN Packet Format --> +<!-- .XE --> +<para> +All XDMCP packets have the following information: +</para> + +<informaltable frame="none"> + <tgroup cols='3' align='left'> + <colspec colname='c1' colsep="0"/> + <colspec colname='c2' colsep="0"/> + <colspec colname='c3' colsep="0"/> + <thead> + <row> + <entry>Length (Bytes)</entry> + <entry>Field Type</entry> + <entry>Description</entry> + </row> + </thead> + <tbody> + <row rowsep="0"> + <entry>2</entry> + <entry>CARD16</entry> + <entry>version number</entry> + </row> + <row rowsep="0"> + <entry>2</entry> + <entry>CARD16</entry> + <entry>opcode packet header</entry> + </row> + <row rowsep="0"> + <entry>2</entry> + <entry>CARD16</entry> + <entry>n = length of remaining data in bytes</entry> + </row> + <row rowsep="0"> + <entry>n</entry> + <entry>???</entry> + <entry>packet-specific data</entry> + </row> + </tbody> + </tgroup> +</informaltable> + +<para> +<!-- .LP --> +The fields are as follows: +</para> + +<variablelist> + <varlistentry> + <term>Version number</term> + <listitem> + <para> +This specifies the version of XDMCP that generated this packet in +case changes in this protocol are required. Displays and +managers may choose to support older versions for compatibility. +This field will initially be one (1). + </para> + </listitem> + </varlistentry> + <varlistentry> + <term>Opcode</term> + <listitem> + <para> +This specifies what step of the protocol this packet represents and should +contain one of the following values (encoding provided in section below): +<emphasis role="bold">BroadcastQuery</emphasis>, +<emphasis role="bold">Query</emphasis>, +<emphasis role="bold">IndirectQuery</emphasis>, +<emphasis role="bold">ForwardQuery</emphasis>, +<emphasis role="bold">Willing</emphasis>, +<emphasis role="bold">Unwilling</emphasis>, +<emphasis role="bold">Request</emphasis>, +<emphasis role="bold">Accept</emphasis>, +<emphasis role="bold">Decline</emphasis>, +<emphasis role="bold">Manage</emphasis>, +<emphasis role="bold">Refuse</emphasis>, +<emphasis role="bold">Failed</emphasis>, +<emphasis role="bold">KeepAlive</emphasis> +or +<emphasis role="bold">Alive</emphasis>. + </para> + </listitem> + </varlistentry> + <varlistentry> + <term>Length of data in bytes</term> + <listitem> + <para> +This specifies the length of the information following the first 6 bytes. +Each packet-type has a different format and will need to be separately +length-checked against this value. Because every data item has either an +explicit or implicit length, this can be easily accomplished. +Packets that have too little or too much data should be ignored. + </para> + </listitem> + </varlistentry> +</variablelist> +<para> +Packets should be checked to make sure that they satisfy the following +conditions: +</para> + +<orderedlist> + <listitem> + <para> +They must contain valid opcodes. + </para> + </listitem> + <listitem> + <para> +The length of the remaining data should correspond to the sum of the +lengths of the individual remaining data items. + </para> + </listitem> + <listitem> + <para> +The opcode should be expected (a finite state diagram is given +in a later section). + </para> + </listitem> + <listitem> + <para> +If the packet is of type +<emphasis role="bold">Manage</emphasis> or +<emphasis role="bold">Refuse</emphasis>, +the Session ID should match the value sent in the preceding +<emphasis role="bold">Accept</emphasis> packet. + </para> + </listitem> +</orderedlist> +</sect1> + +<sect1 id="Protocol"> +<title>Protocol</title> +<!-- .XS --> +<!-- (SN Protocol --> +<!-- .XE --> +<para> +Each of the opcodes is described below. Because a given packet type is only +ever sent one way, each packet description below indicates the direction. +Most of the packets have additional information included beyond the +description above. The additional information is appended to the packet +header in the order described without padding, and the length field is +computed accordingly. +</para> + +<informaltable frame="none"> + <tgroup cols='10' align='left'> + <colspec colname='col1' colsep="0" colwidth="1*"/> + <colspec colname='col2' colsep="0" colwidth="1*"/> + <colspec colname='col3' colsep="0" colwidth="1*"/> + <colspec colname='col4' colsep="0" colwidth="1*"/> + <colspec colname='col5' colsep="0" colwidth="1*"/> + <colspec colname='col6' colsep="0" colwidth="1*"/> + <colspec colname='col7' colsep="0" colwidth="1*"/> + <colspec colname='col8' colsep="0" colwidth="1*"/> + <colspec colname='col9' colsep="0" colwidth="1*"/> + <colspec colname='col10' colsep="0" colwidth="1*"/> + <spanspec namest="col1" nameend="col10" spanname="col1_on" align="left"/> + <spanspec namest="col2" nameend="col10" spanname="col2_on" align="left"/> + <spanspec namest="col3" nameend="col10" spanname="col3_on" align="left"/> + <spanspec namest="col4" nameend="col10" spanname="col4_on" align="left"/> + <spanspec namest="col5" nameend="col10" spanname="col5_on" align="left"/> + <tbody> + <row rowsep="0"> + <entry spanname="col1_on"><emphasis role="bold">Query</emphasis></entry> + </row> + <row rowsep="0"> + <entry spanname="col1_on"><emphasis role="bold">BroadcastQuery</emphasis></entry> + </row> + <row rowsep="0"> + <entry spanname="col1_on"><emphasis role="bold">IndirectQuery</emphasis></entry> + </row> + <row rowsep="0"> + <entry></entry> + <entry spanname="col2_on">Display -> Manager</entry> + </row> + <row rowsep="0"> + <entry></entry> + <entry spanname="col2_on">Additional Fields:</entry> + </row> + <row rowsep="0"> + <entry></entry> + <entry></entry> + <entry spanname="col3_on"> +<emphasis>Authentication Names</emphasis>: ARRAYofARRAY8 + </entry> + </row> + <row rowsep="0"> + <entry></entry> + <entry></entry> + <entry></entry> + <entry spanname="col4_on"> +Specifies a list of authentication names that the display supports. The +manager will choose one of these and return it in the +<emphasis role="bold">Willing</emphasis> packet. + </entry> + </row> +<!-- AAAAAAAAAAAAA --> + <row rowsep="0"> + <entry></entry> + <entry></entry> + <entry>Semantics</entry> + </row> + <row rowsep="0"> + <entry></entry> + <entry></entry> + <entry></entry> + <entry spanname="col4_on"> +<para> +A <function>Query</function> +packet is sent from the display to a specific host to ask if +that host is willing to provide management services to this display. The +host should respond with +<function>Willing</function> +if it is willing to service the display or +<function>Unwilling</function> +if it is not. +</para> + +<para> +A +<function>BroadcastQuery</function> +packet is similar to the +<function>Query</function> +packet except that it is intended to be received by all hosts on the network +(or subnetwork). However, unlike +<function>Query</function> +requests, hosts that are not willing to service the display +should simply ignore +<function>BroadcastQuery</function> +requests. +</para> + +<para> +An +<function>IndirectQuery</function> +packet is sent to a well known manager that forwards +the request to a larger collection of secondary managers using +<function>ForwardQuery</function> +packets. +In this way, the collection of managers that respond can be grouped +on other than network boundaries; the use of a central manager reduces +system administrative overhead. +The primary manager may also send a +<function>Willing</function> +packet in response to this packet. +</para> + +<para> +Each packet type has slightly different semantics: +</para> + </entry> + </row> + <row rowsep="0"> + <entry></entry> + <entry></entry> + <entry></entry> + <entry></entry> + <entry spanname="col5_on"> +<para> +The +<function>Query</function> +packet is destined only for a single host. +If the display is instructed to +<function>Query</function> +multiple managers, it will send multiple +<function>Query</function> +packets. The +<function>Query</function> +packet also demands a response from the manager, either +<function>Willing</function> +or +<function>Unwilling</function>. + </para> + <para> +The +<function>BroadcastQuery</function> +packet is sent to many hosts. +Each manager that receives this packet will not respond with an +<function>Unwilling</function> +packet. + </para> + <para> +The +<function>IndirectQuery</function> +packet is sent to only one manager with the request +that the request be forwarded to a larger list of managers using +<function>ForwardQuery</function> +packets. This list is expected to be maintained at one +central site to reduce administrative overhead. +The function of this packet type is similar to +<function>BroadcastQuery except that</function> +<function>BroadcastQuery</function> +is not forwarded. + </para> + </entry> + </row> + <row rowsep="0"> + <entry></entry> + <entry></entry> + <entry></entry> + <entry spanname="col4_on">Valid Responses:</entry> + </row> + <row rowsep="0"> + <entry></entry> + <entry></entry> + <entry spanname="col3_on"> +<function>Willing</function>, +<function>Unwilling</function> + </entry> + </row> + <row rowsep="0"> + <entry></entry> + <entry></entry> + <entry></entry> + <entry spanname="col4_on">Problems/Solutions:</entry> + </row> + <row rowsep="0"> + <entry></entry> + <entry></entry> + <entry spanname="col3_on">Problem:</entry> + </row> + <row rowsep="0"> + <entry></entry> + <entry></entry> + <entry></entry> + <entry spanname="col4_on"> +<para>Not all managers receive the query packet.</para> +<para>Indication:</para> + </entry> + </row> + <row rowsep="0"> + <entry></entry> + <entry></entry> + <entry></entry> + <entry></entry> + <entry spanname="col5_on"> +None if +<function>BroadcastQuery</function> +or +<function>IndirectQuery</function> +was sent, else failure to receive +<function>Willing</function>. + </entry> + </row> + <row rowsep="0"> + <entry></entry> + <entry></entry> + <entry></entry> + <entry spanname="col4_on">Solution:</entry> + </row> + <row rowsep="0"> + <entry></entry> + <entry></entry> + <entry></entry> + <entry></entry> + <entry spanname="col5_on"> +Repeatedly send the packet while waiting for user to choose a manager. + </entry> + </row> + <row rowsep="0"> + <entry></entry> + <entry></entry> + <entry spanname="col3_on"> +Timeout/Retransmission policy: + </entry> + </row> + <row rowsep="0"> + <entry></entry> + <entry></entry> + <entry></entry> + <entry spanname="col4_on"> +An exponential backoff algorithm should be used here to reduce network load +for long-standing idle displays. Start at 2 seconds, back off by factors of +2 to 32 seconds, and discontinue retransmit after 126 seconds. The display +should reset the timeout when user-input is detected. In this way, the +display will wakeup when touched by the user. + </entry> + </row> + <row rowsep="0"> + <entry spanname="col1_on"> +<function>ForwardQuery</function> + </entry> + </row> + <row rowsep="0"> + <entry></entry> + <entry spanname="col2_on"> +<para>Primary Manager -> Secondary Manager</para> +<para>Additional Fields:</para> + </entry> + </row> + <row rowsep="0"> + <entry></entry> + <entry></entry> + <entry spanname="col3_on"> +<emphasis remap='I'>Client Address</emphasis>: ARRAY8 + </entry> + </row> + <row rowsep="0"> + <entry></entry> + <entry></entry> + <entry></entry> + <entry spanname="col4_on"> +Specifies the network address of the client display. + </entry> + </row> + <row rowsep="0"> + <entry></entry> + <entry></entry> + <entry spanname="col3_on"> +<emphasis remap='I'>Client Port</emphasis>: ARRAY8 + </entry> + </row> + <row rowsep="0"> + <entry></entry> + <entry></entry> + <entry></entry> + <entry spanname="col4_on"> +Specifies an identification of the client task on the client display. + </entry> + </row> + <row rowsep="0"> -- To UNSUBSCRIBE, email to [email protected] with a subject of "unsubscribe". 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