\input texinfo @c -*-texinfo-*- @c %**start of header @setfilename uucp.info @settitle Taylor UUCP @setchapternewpage odd @c %**end of header @setchapternewpage odd @ignore ----------------------------------------------------------------------> Franc,ois Pinard says: Hi, Ian! This is the promised merging of the current documents from Taylor UUCP 1.01, plus the patches to documentation you sent to me, into a taylor.texi file. Many things remain to do, among which: - merging in the Taylor UUCP program man pages. - integrating the three documents describing the protocol. - gleaning miscellaneous information from my archives. ----------------------------------------------------------------------< @end ignore @ifinfo This file documents Taylor UUCP, version 1.03. Copyright @copyright{} 1992 Free Software Foundation, Inc. Permission is granted to make and distribute verbatim copies of this manual provided the copyright notice and this permission notice are preserved on all copies. @ignore Permission is granted to process this file through TeX and print the results, provided the printed document carries a copying permission notice identical to this one except for the removal of this paragraph (this paragraph not being relevant to the printed manual). @end ignore Permission is granted to copy and distribute modified versions of this manual under the conditions for verbatim copying, provided also that the section entitled ``Copying'' are included exactly as in the original, and provided that the entire resulting derived work is distributed under the terms of a permission notice identical to this one. Permission is granted to copy and distribute translations of this manual into another language, under the above conditions for modified versions, except that the section entitled ``Copying'' may be included in a translation approved by the author instead of in the original English. @end ifinfo @titlepage @title Taylor UUCP @subtitle Version 1.03 @author Ian Lance Taylor @file{} @page @vskip 0pt plus 1filll Copyright @copyright{} 1992 Free Software Foundation, Inc. Published by Ian Lance Taylor @file{}. Permission is granted to make and distribute verbatim copies of this manual provided the copyright notice and this permission notice are preserved on all copies. Permission is granted to copy and distribute modified versions of this manual under the conditions for verbatim copying, provided also that the section entitled ``Copying'' are included exactly as in the original, and provided that the entire resulting derived work is distributed under the terms of a permission notice identical to this one. Permission is granted to copy and distribute translations of this manual into another language, under the above conditions for modified versions, except that the section entitled ``Copying'' may be included in a translation approved by the author instead of in the original English. @end titlepage @node Top, Copying, (dir), (dir) @top Taylor UUCP 1.03 This is the documentation for the Taylor UUCP package, version 1.03. The programs were written by Ian Lance Taylor. The author can be reached at @file{}, or, equivalently, @file{}, or @cite{c/o Infinity Development, P.O. Box 520, Waltham MA, 02254}. There is a mailing list for discussion of the package. To join the list, send a message to @file{}. Make sure you include the address you want to receive messages at; do not rely on the @code{From:} header. To send a message to the list, send it to @file{}. @menu * Copying:: Taylor UUCP copying conditions * Introduction:: Introduction to Taylor UUCP * Overall Installation:: Taylor UUCP installation * Configuration Files:: Taylor UUCP configuration files * Protocols:: UUCP protocol internals * Hacking:: Hacking Taylor UUCP * Acknowledgements:: Acknowledgements * Index (concepts):: Concept index * Index (configuration file):: Index to new configuration files --- The Detailed Node Listing --- Taylor UUCP Overall Installation * Configuration:: Configuring Taylor UUCP * Compilation:: Compiling Taylor UUCP * Testing:: Testing Taylor UUCP * Installation:: Installing Taylor UUCP * Usage:: Using Taylor UUCP * TCP:: TCP together with Taylor UUCP Taylor UUCP Configuration Files * Configuration File Format:: Configuration file format * Configuration Examples:: Examples of configuration files * Time Strings:: How to write time strings * Chat Scripts:: How to write chat scripts * config File:: The main configuration file * sys File:: The system configuration file * port File:: The port configuration files * dial File:: The dialer configuration files * Security:: Security issues Examples of Configuration Files * config File Examples:: Examples of the main configuration file * Leaf Example:: Call a single remote site * Gateway Example:: The gateway for several local systems The Main Configuration File * Miscellaneous (config):: Miscellaneous config file commands * Configuration File Names:: Using different configuration files * Log File Names:: Using different log files * Debugging Levels:: Debugging levels The System Configuration File * Defaults and Alternates:: Using defaults and alternates * Naming the System:: Naming the system * Calling Out:: Calling out * Accepting a Call:: Accepting a call * Protocol Selection:: Protocol selection * File Transfer Control:: File transfer control * Miscellaneous (sys):: Miscellaneous sys file commands * Default sys File Values:: Default values Calling Out * When to Call:: When to call * Placing the Call:: Placing the call * Logging In:: Logging in UUCP protocol internals * Grades:: UUCP grades * Lock Files:: UUCP lock file format * UUCP Protocol:: The common UUCP protocol * g Protocol:: The UUCP @samp{g} protocol * f Protocol:: The UUCP @samp{f} protocol * t Protocol:: The UUCP @samp{t} protocol * e Protocol:: The UUCP @samp{e} protocol * x Protocol:: The UUCP @samp{x} protocol * d Protocol:: The UUCP @samp{d} protocol * Capital G Protocol:: The UUCP @samp{G} protocol * Documentation References:: Documentation references The Common UUCP Protocol * Initial Handshake:: Initial handshake * File Requests:: File requests * Final Handshake:: Final handshake File Requests * S Request:: S request * R Request:: R request * X Request:: X request * H Request:: H request Hacking Taylor UUCP * System Dependence:: System Dependence * Naming Conventions:: Naming Conventions * Patches:: Patches @end menu @node Copying, Introduction, Top, Top @unnumbered Taylor UUCP Copying Conditions This package is covered by the GNU Public License. See the file @file{COPYING} for details. If you would like to do something with this package that you feel is reasonable but you feel is prohibited by the license, contact me to see if we can work it out. Here is some propaganda from the Free Software Foundation. If you find this stuff offensive or annoying, remember that you probably did not spend any money to get this code. I did not write this code to make life easier for developers of UUCP packages, I wrote it to help end users, and I believe that these are the most appropriate conditions for distribution. All the programs, scripts and documents relating to Taylor UUCP are @dfn{free}; this means that everyone is free to use them and free to redistribute them on a free basis. The Taylor UUCP-related programs are not in the public domain; they are copyrighted and there are restrictions on their distribution, but these restrictions are designed to permit everything that a good cooperating citizen would want to do. What is not allowed is to try to prevent others from further sharing any version of these programs that they might get from you. Specifically, we want to make sure that you have the right to give away copies of the programs that relate to Taylor UUCP, that you receive source code or else can get it if you want it, that you can change these programs or use pieces of them in new free programs, and that you know you can do these things. To make sure that everyone has such rights, we have to forbid you to deprive anyone else of these rights. For example, if you distribute copies of the Taylor UUCP related programs, you must give the recipients all the rights that you have. You must make sure that they, too, receive or can get the source code. And you must tell them their rights. Also, for our own protection, we must make certain that everyone finds out that there is no warranty for the programs that relate to Taylor UUCP. If these programs are modified by someone else and passed on, we want their recipients to know that what they have is not what we distributed, so that any problems introduced by others will not reflect on our reputation. The precise conditions of the licenses for the programs currently being distributed that relate to Taylor UUCP are found in the General Public Licenses that accompany them. @node Introduction, Overall Installation, Copying, Top @chapter Introduction to Taylor UUCP General introductions to UUCP are available, and perhaps one day I will write one. In the meantime, here is a very brief one that concentrates on the programs provided by Taylor UUCP. Taylor UUCP is a complete UUCP package. It is covered by the GNU Public License, which means that the source code is always available. It is composed of several programs, the names of which were established by earlier UUCP packages. @table @code @item uucp The @code{uucp} program is used to copy file between systems. It is similar to the standard Unix @code{cp} program, except that you can refer to a file on a remote system by using @samp{system!} before the file name. For example, to copy the file @file{notes.txt} to the system @samp{airs}, you would say @samp{uucp notes.txt airs!~/notes.txt}. In this example @samp{~} is used to name the UUCP public directory on @samp{airs}. @item uux The @code{uux} program is used to request a program to be executed on a remote system. This is how mail and news are transferred over UUCP. As with @code{uucp}, programs and files on remote systems may be named by using @samp{system!}. For example, to run the @code{rnews} program on @samp{airs} passing it standard input, you would say @samp{uux - airs!rnews}. The @samp{-} means to read standard input and set things up so that when @code{rnews} runs on @samp{airs} it will receive the same standard input. @end table Neither @code{uucp} nor @code{uux} actually do any work immediately. Instead, they queue up requests for later processing. They then start a daemon process which processes the requests and calls up the appropriate systems. Usually the daemon will also be started regularly to check if there is any work to be done and to do it. The advantage of this system is that it all happens automatically. You don't have to sit around waiting for the files to be transferred. The disadvantage is that if anything goes wrong it might be a while before anybody notices. @table @code @item uustat The @code{uustat} program does several things. By default it will simply list all the jobs you have queued with @code{uucp} or @code{uux} that have not yet been processed. You can use @code{uustat} to remove any of your jobs from the queue. You can also it use it to show the status of the UUCP system in various ways, such as showing the connection status of all systems your system knows about. @item uuname The @code{uuname} program by default lists all the remote systems your system knows about. You can also use it to get the name of your local system. It is mostly useful for shell scripts. @item uulog The @code{uulog} program can be used to display entries in the UUCP log file. It can select the entries for a particular system or a particular user. You can use it to see what has happened to your queued jobs in the past. @end table These five programs just described, @code{uucp}, @code{uux}, @code{uustat}, @code{uuname}, and @code{uulog}, are the user programs provided by Taylor UUCP. The first two add requests to the work queue, the third examines the work queue, the fourth examines the configuration files, and the last examines the log files. The real work is actually done by two daemon processes, which are normally run automatically rather than by a user. @table @code @item uucico The @code{uucico} daemon is the program which actually calls the remote system and transfers files and requests. @code{uucico} is normally started automatically by @code{uucp} and @code{uux}. Most systems will also start it periodically to make sure that all work requests are handled. @code{uucico} checks the queue to see what work needs to be done, and then calls the appropriate systems. If the call fails, perhaps because the phone line is busy, @code{uucico} leaves the requests in the queue and goes on to the next system to call. It is also possible to force @code{uucico} to call a remote system even if there is no work to be done for it, so that it can pick up any work that may be queued up remotely. @item uuxqt The @code{uuxqt} daemon processes execution requests made by the @code{uux} program on remote systems. It also processes requests made on the local system which require files from a remote system. It is normally started by @code{uucico}. @end table Suppose you, on the system @samp{bantam}, want to copy a file to the system @samp{airs}. You would run the @code{uucp} command locally, with a command like @samp{uucp notes.txt airs!~/notes.txt}. This would queue up a request on @samp{bantam} for @samp{airs}, and would then start the @code{uucico} daemon. @code{uucico} would see that there was a request for @samp{airs} and attempt to call it. When the call succeeded, another copy of @code{uucico} would be started on @samp{airs}. The two copies of @code{uucico} would tell each other what they had to do and transfer the file from @samp{bantam} to @samp{airs}. When the file transfer was complete the @code{uucico} on @samp{airs} would move it into the UUCP public directory. UUCP is often used to transfer mail. This is normally done automatically by mailer programs. When @samp{bantam} has a mail message to send to @samp{ian} at @samp{airs}, it executes @samp{uux - airs!rmail ian} and writes the mail message to the @code{uux} process as standard input. The @code{uux} program, running on @samp{bantam}, will read the standard input and store it and the @code{rmail} request on the work queue for @code{airs}. @code{uux} will then start the @code{uucico} daemon. The @code{uucico} daemon will call up @samp{airs}, just as in the @code{uucp} example, and transfer the work request and the mail message itself. The @code{uucico} daemon on @samp{airs} will put the files on a local work queue. When the communication session is over, the @code{uucico} daemon on @samp{airs} will start the @code{uuxqt} daemon. @code{uuxqt} will see the request to run, and will run @samp{rmail ian} with the mail message as standard input. The @code{rmail} program, which is not part of the UUCP package, is then responsible for either putting the message in the right mailbox on @samp{airs} or forwarding the message on to another system. Taylor UUCP comes with two other programs that are useful when installing and configuring UUCP. @table @code @item uuchk The @code{uuchk} program reads the UUCP configuration files and displays a rather lengthy description of what it finds. This is very useful when configuring UUCP to make certain that the UUCP package will do what you expect it to do. @item tstuu The @code{tstuu} program is a test harness for the UUCP package, which will help ensure that it has been configured and compiled correctly. It does not test everything, however, and it only runs on Unix systems which support Berkeley style pseudo-terminals. It can be useful when initially installing Taylor UUCP. @end table @node Overall Installation, Configuration Files, Introduction, Top @chapter Taylor UUCP Overall Installation These are the installation instructions for the Taylor UUCP package. @menu * Configuration:: Configuring Taylor UUCP * Compilation:: Compiling Taylor UUCP * Testing:: Testing Taylor UUCP * Installation:: Installing Taylor UUCP * Usage:: Using Taylor UUCP * TCP:: TCP together with Taylor UUCP @end menu @node Configuration, Compilation, Overall Installation, Overall Installation @section Configuring Taylor UUCP You will have to decide what types of configuration files you want to use. This package supports a new sort of configuration file; @xref{Configuration files}. It also supports V2 configuration files (@file{L.sys}, @file{L-devices}, etc.) and BNU configuration files (@file{Systems}, @file{Devices}, etc.). No documentation is provided for V2 or BNU configuration files. All types of configuration files can be used at once, if you are so inclined. Currently using just V2 configuration files is not really possible, because there is no way to specify a dialer (there are no built in dialers, and the program does not know how to read @file{acucap} or @file{modemcap}); however, V2 configuration files can be used with a new style dialer file (@pxref{dial file}), or with a BNU @file{Dialers} file. Use of BNU configuration files has two known bugs. A blank line in the middle of an entry in the @file{Permissions} file will not be ignored as it should be. Dialer programs are not recognized directly. If you must use a dialer program, rather than an entry in @file{Devices}, you must use the @code{chat-program} command in a new style dialer file; see @ref{dial file}. You will have to invoke the dialer program via a shell script, since an exit code of 0 is required to recognize success. If you are installing a new system, or you want to use the new form of configuration files, you must write the configuration files. You must also decide what sort of spool directory you want to use. If you will only be using these programs, I recommend @samp{SPOOLDIR_TAYLOR}; otherwise select the spool directory corresponding to your existing UUCP package. The details of the spool directory choices are described at somewhat tedious length in @file{sys3.unx}. @node Compilation, Testing, Configuration, Overall Installation @section Compiling Taylor UUCP @enumerate @item Take a look at the top of @file{Makefile.in} and set the appropriate values for your system. These control where the program is installed and which user on the system owns them (normally they will be owned by a special user @code{uucp} rather than a real person; they should probably not be owned by @code{root}). @item Run the shell script @code{configure}. This script was generated using David MacKenzie's @code{autoconf} program. It takes a while to run. It will generate a file @file{conf.h}, and copy @file{Makefile.in} to @file{Makefile} with substitions (specifically, it will replace all words between @kbd{@@} characters in @file{Makefile.in}). You can pass certain arguments to @code{configure} in the environment. Because @code{configure} will compile and run little test programs to see what is available on your system, you must tell it how to run your compiler. It recognizes the following environment variables: @table @samp @item CC The C compiler. If this is not set, then if @code{configure} can find @code{gcc} it will use @samp{gcc -O}, otherwise it will use @samp{cc}. @item DEFS Flags to pass the C compiler during configuration testing. If this is not set, @code{configure} will use the empty string. @item CFLAGS Flags to pass to the C compiler when compiling the actual code. If this is not set, @code{configure} will use @samp{-g}. @item LDFLAGS Flags to pass to the C compiler when only linking, not compiling. If this is not set, @code{configure} will use the empty string. @item LIBS Libraries to pass to the C compiler. If this is not set, @code{configure} will use the empty string. @item INSTALL The program to run to install UUCP in the binary directory. If @code{configure} finds the BSD @code{install} program, it will set this to @samp{install -c}; otherwise, it will use @samp{cp}. @item INSTALLDATA The program to run to install UUCP data files, such as the man pages and the info pages. If @code{configure} finds the BSD @code{install} program, it will set this to @samp{install -c -m 644}; otherwise, it will use @samp{cp}. @end table Suppose you want to set the environment variable @samp{CC} to @samp{rcc}. If you are using @code{sh} or @code{bash}, invoke @code{configure} as @samp{CC=rcc configure}. If you are using @code{csh}, do @samp{setenv CC rcc; sh configure}. On some systems you will want to use @samp{LIBS=-lmalloc}. On some you will want @samp{LIBS=-lsocket}. On Xenix derived systems do not use @samp{LIBS=-lx} because this will bring in the wrong versions of certain routines; if you want to use @samp{-lx} you must specify @samp{LIBS=-lc -lx}. If @code{configure} fails for some reason, or if you have a very wierd system, you may have to configure the package by hand. To do this, copy the file @file{conf.h-dist} to @file{conf.h} and edit it for your system. Then copy @file{Makefile.in} to @file{Makefile}, find the words within @kbd{@@} characters, and set them correctly for your system. @item You should verify that @code{configure} worked correctly by checking the files @file{conf.h} and @file{Makefile}. @item This package uses the @code{alloca} function. The @code{configure} script will try to figure out how to make it work on your system. If @code{alloca} cannot be found, a simplistic substitute from @file{alloca.c} will be used. If you provide your own @file{alloca.o} file, it will be used instead; you might, for example, use the one from the GNU emacs distribution. If none of this makes any sense to you, don't worry; everything will probably work fine. @item Edit @file{policy.h} for your local system. The comments should explain the various choices. The default values are intended to be reasonable, so you may not have to make any changes. @item Type @samp{make} to compile everything. You may get warnings about implicit function declarations; ignore these (if you think they can be eliminated, and you really know what you are talking about, you may tell me about them). You may also get warnings about @file{getopt.c} (this is from the GNU library and I do not want to change it) and about a variable not protected from @code{setjmp} in @file{sys2.c} (the data flow ensures that this can never be a problem). The @file{tstuu.c} file is not particularly portable; if you can't figure out how to compile it you can safely ignore it, as it is only used for testing. If you have any other problems there is probably a bug in the @code{configure} script. @item Please report any problems you have. That is the only way they will get fixed for other people. Supply a patch if you can, or just ask for help. @end enumerate @node Testing, Installation, Compilation, Overall Installation @section Testing Taylor UUCP This package is in use at many sites, and has been running at @file{airs.com} for several months. However, it will doubtless fail in some situations. Do not rely on this code until you have proven to yourself that it will work. You can use the @code{uuchk} program to test your configuration files. It will read them and print out a verbose description. This is particularly important if you are using V2 or BNU configuration files, because there may be bugs in how they are read. This program should not be made suid, because it will display passwords if it can read them. If your system supports BSD style pseudo-terminals, and you compiled the code to support the new style of configuration files, you should be able to use the @code{tstuu} program to test the @code{uucico} daemon. Just type @samp{tstuu} with no arguments while logged in to the compilation directory (since it runs @file{./uucp}, @file{./uux} and @file{./uucico}) to run a lengthy series of tests (it takes over ten minutes on a slow VAX). You will need a fair amount of space available in @file{/usr/tmp}. You will probably want to put it in the background. Do not use @kbd{^Z}, because the program traps on @code{SIGCHLD} and winds up dying. It will create a directory @file{/usr/tmp/tstuu} and fill it with configuration files, and create spool directories @file{/usr/tmp/tstuu/spool1} and @file{/usr/tmp/tstuu/spool2}. The program will finish with an execute file @file{X.@var{something}} and a data file @file{D.@var{something}} in @file{/usr/tmp/tstuu/spool1} (or, more likely, in subdirectories, depending on the choice of @code{SPOOLDIR} in @file{sysdep.h}). The log files @file{/usr/tmp/tstuu/Log1} and @file{/usr/tmp/tstuu/Log2} (or, if you have selected @code{HAVE_BNU_LOGGING}, @file{/usr/tmp/tstuu/Log1/uucico/test2} and @file{/usr/tmp/tstuu/Log2/uucico/test1}) should look fairly normal. You can test @code{uuxqt} by typing @samp{./uuxqt -I /usr/tmp/tstuu/Config1}. This should leave a command file @file{C.@var{something}} and a data file @file{D.@var{something}} in @file{/usr/tmp/tstuu/spool1} or in subdirectories. Again, there should be no errors in the log file. Assuming you compiled the code with debugging enabled, the @samp{-x} switch can be used to set debugging modes; see the @code{debug} command for details (@pxref{Debugging Levels}). Use @samp{-x all} to turn on all debugging and generate far more output than you will ever want to see. The @code{uucico} daemons will put debugging output in @file{/usr/tmp/tstuu/Debug1} and @file{/usr/tmp/tstuu/Debug2}. At this point you're pretty much on your own. On some systems you can also use @code{tstuu} to test my @code{uucico} against the system @code{uucico}, by using the @samp{-u} switch. For this to work, change the definitions of @code{ZUUCICO_CMD} and @code{UUCICO_EXECL} at the top of @file{tstuu.c} to something appropriate for your system. The definitions in @file{tstuu.c} are what I used for Ultrix 4.0, in which @file{/usr/lib/uucp/uucico} is particularly obstinate about being run as a child; I was only able to run it by creating a login name with no password whose shell was @file{/usr/lib/uucp/uucico}. Calling login in this way will leave fake entries in @file{wtmp} and @file{utmp}; if you compile @file{tstout.c} (in the @file{contrib} directory) as an suid @code{root} program, @code{tstuu} will run it to clear those entries out. On most systems, such hackery should not be necessary, although on SCO I had to su to @code{root} (@code{uucp} might also have worked) before I could run @file{/usr/lib/uucp/uucico}. You can test @code{uucp} and @code{uux} (give them the @samp{-r} switch to keep them from starting @code{uucico}) to make sure they create the right sorts of files. Unfortunately if you don't know what the right sorts of files are I'm not going to tell you here. If @code{tstuu} passes, or you can't run it for some reason or other, move on to testing with some other system. Set up the configuration files (@pxref{Configuration files}), or use an existing configuration. Tell @code{uucico} to dial out to the system by using the @samp{-s} system switch (e.g. @samp{uucico -s uunet}). The log file should tell you what happens. If you compiled the code with debugging enabled, you can use debugging mode to get a great deal of information about what sort of data is flowing back and forth; the various possibilities are described under the @code{debug} command (@pxref{Debugging Levels}). When initially setting up a connection @samp{-x chat} is probably the most useful (e.g. @samp{uucico -s uunet -x chat}); you may also want to use @samp{-x handshake,incoming,outgoing}. You can use @samp{-x} multiple times on one command line, or you can give it comma separated arguments as in the last example. Use @samp{-x all} to turn on all possible debugging information. The debugging information is written to a file, normally @file{/usr/spool/uucp/Debug} although the default can be changed in @file{policy.h} and the configuration file can override the name with the @code{debugfile} command. The debugging file may contain passwords and some file contents as they are transmitted over the line, so the debugging file is only readable by the @code{uucp} user. You can use the @samp{-f} switch to force @code{uucico} to call out even if the last call failed recently; using @samp{-S} when naming a system has the same effect. Otherwise the status file (in the @file{.Status} subdirectory of the main spool directory, normally @file{/usr/spool/uucp}) will prevent too many attempts from occurring in rapid succession. Again, let me know about any problems you have and how you got around them. @node Installation, Usage, Testing, Overall Installation @section Installing Taylor UUCP You can install by suing to @code{root} and typing @samp{make install}. Or you can look at what make install does and do it by hand. It tries to preserve your old programs, if any. You can retrieve them by typing @samp{make uninstall}. @node Usage, TCP, Installation, Overall Installation @section Using Taylor UUCP This package does not come with any fancy shell scripts or scheduling programs. Maybe someday. If you have another package, you may well be able to use the scheduling mechanisms it provides. Otherwise, the program can be used by making crontab entries. Whenever you want to call all systems with outstanding work, use @example uucico -r1 @end example Whenever you want to call a specific system @samp{foo}, use @example uucico -s foo @end example If you want to make sure that a system foo gets retried if the original call fails, create an empty work file for it. For example, if using @code{SPOOLDIR_TAYLOR}, @example touch /usr/spool/uucp/foo/C./C.A0000 @end example If using @code{SPOOLDIR_BNU}, use @example touch /usr/spool/uucp/foo/C.fooA0000 @end example I use the following crontab entries locally: @example 45 * * * * /bin/echo /usr/lib/uucp/uucico -r1 | /bin/su uucpa 40 4,10,15 * * * touch /usr/spool/uucp/uunet/C./C.A0000 @end example Every hour, at 45 minutes past, this will check if there is any work to be done. Also, at 4:40am, 10:40am and 3:40pm this will create an empty work file for @file{uunet}, forcing the next check to call @file{uunet}. You will also want to periodically trim the log files, which by default are @file{/usr/spool/uucp/Log} and @file{/usr/spool/uucp/Stats}. The @code{savelog} program in the @file{contrib} directory may be of use. @node TCP, , Usage, Overall Installation @section TCP together with Taylor UUCP If your system has a Berkeley style socket library, you can compile the code to permit making connections over TCP. Specifying that a system should be reached via TCP is easy, but nonobvious. If you are using the new style configuration files, see @ref{Configuration files}. Basically, you can just add the line @samp{port type tcp} to the entry in the system configuration file. By default UUCP will get the port number by looking up @samp{uucp} in @file{/etc/services}; if @samp{uucp} is not found, port 540 will be used. You can set the port number to use with the command @samp{port service @var{xxx}}, where @var{xxx} can be either a number or a name to look up in @file{/etc/services}. You can specify the address of the remote host with @samp{address @var{a.b.c}}; if you don't give an address, the remote system name will be used. You should give an explicit chat script for the system when you use TCP; the default chat script begins with a carriage return, which will not work with some UUCP TCP servers. If you are using V2 configuration files, add a line like this to @file{L.sys}: @example foo Any TCP uucp foo.domain chat-script @end example This will make an entry for system foo, to be called at any time, over TCP, using port number @samp{uucp} (as found in @file{/etc/services}; this may be specified as a number), using remote host @file{foo.domain}, with some chat script. If you are using BNU configuration files, add a line like this to Systems: @example foo Any TCP - foo.domain chat-script @end example and a line like this to Devices: @example TCP uucp - - @end example You only need one line in Devices regardless of how many systems you contact over TCP. This will make an entry for system foo, to be called at any time, over TCP, using port number @samp{uucp} (as found in @file{/etc/services}; this may be specified as a number), using remote host @file{foo.domain}, with some chat script. The @code{uucico} daemon can also be run as a TCP server. This code mostly works, but it's not perfect. I don't recommend investigating it unless you are willing to tinker a bit. You will not be able to use the default port number because @code{uucico} will not be running as @code{root} and will therefore not be able to bind a reserved port. Basically, you must define a port, either using the port file (@pxref{port file}) if you are using the new configuration method or with an entry in Devices if you are using BNU; there is no way to define a port using V2. If you are using BNU the port must be named @samp{TCP}; a line as shown above will suffice. You can then start @code{uucico} as @samp{uucico -p TCP} (after the @samp{-p}, name the port; in BNU it must be @samp{TCP}). This will wait for incoming connections, and fork off a child for each one. Each connection will be prompted with @samp{login:} and @samp{Password:}; the results will be checked against the UUCP (not the system) password file (@pxref{Configuration File Names}). Of course, you can get a similar effect by using the BSD @code{uucpd} program. You can also have @code{inetd} start up @code{uucico} with the @samp{-l} switch, which will cause it to prompt with @samp{login:} and @samp{Password:} and check the results against the UUCP (not the system) password file. This may be used in place of @code{uucpd}. @node Configuration Files, Protocols, Overall Installation, Top @chapter Taylor UUCP Configuration Files This chapter describes the configuration files accepted by the Taylor UUCP package if compiled with @code{HAVE_TAYLOR_CONFIG} defined in @file{conf.h}. The configuration files are normally found in the directory @var{newconfigdir}, which is defined by the @file{Makefile} variable @file{newconfigdir}; by default @var{newconfigdir} is @file{/usr/local/lib/uucp}. However, the main configuration file, @file{config}, is the only one which must be in that directory, since it may specify a different location for any or all of the other files. You may run any of the UUCP programs with a different main configuration file by using the @samp{-I} option; this can be useful when testing a new configuration. When you use the @samp{-I} option the programs will revoke their setuid privileges. @menu * Configuration File Format:: Configuration file format * Configuration Examples:: Examples of configuration files * Time Strings:: How to write time strings * Chat Scripts:: How to write chat scripts * config File:: The main configuration file * sys File:: The system configuration file * port File:: The port configuration files * dial File:: The dialer configuration files * Security:: Security issues @end menu @node Configuration File Format, Configuration Examples, Configuration Files, Configuration Files @section Configuration File Format All the configuration files follow a simple line-oriented @samp{@var{keyword} @var{value}} format. Empty lines are ignored, as are leading spaces; unlike BNU, lines with leading spaces are read. The first word on each line is a keyword. The rest of the line is interpreted according to the keyword. Most keywords are followed by numbers, boolean values or simple strings with no embedded spaces. The @kbd{#} character is used for comments. Everything from a @kbd{#} to the end of the line is ignored unless the @kbd{#} is preceded by a @kbd{\} (backslash); if the @kbd{#} is preceeded by a @kbd{\}, the @kbd{\} is removed but the @kbd{#} remains in the line. This can be useful for a phone number containing a @kbd{#}. To enter the sequence @samp{\#}, you would use @samp{\\#}. The backslash character may be used to continue lines. If the last character in a line is a backslash, the backslash is removed and the line is continued by the next line. The second line is attached to the first with no intervening characters; if you want any whitespace between the end of the first line and the start of the second line, you must insert it yourself. However, the backslash is not a general quoting character. For example, you cannot use it to get an embedded space in a string argument. Everything after the keyword must be on the same line. A @var{boolean} may be specified as @kbd{y}, @kbd{Y}, @kbd{t}, or @kbd{T} for true and @kbd{n}, @kbd{N}, @kbd{f}, or @kbd{F} for false; any trailing characters are ignored, so @code{true}, @code{false}, etc., are also acceptable. @node Configuration Examples, Time Strings, Configuration File Format, Configuration Files @section Examples of Configuration Files All the configuration commands are explained in the following sections. However, I'll start by giving a few examples of configuration files. For a more complete description of any of the commands used here see the appropriate section of this chapter. @menu * config File Examples:: Examples of the main configuration file * Leaf Example:: Call a single remote site * Gateway Example:: The gateway for several local systems @end menu @node config File Examples, Leaf Example, Configuration Examples, Configuration Examples @subsection config File Examples @cindex config file examples To start with, here are some examples of uses of the main configuration file, @file{config}. For a complete description of the commands that are permitted in @file{config}, see @ref{config file}. In many cases you will not need to create a @file{config} file at all. The most common reason to create one is to give your machine a special UUCP name. Other reasons might be to change the UUCP spool directory or to permit any remote system to call in. If you have an internal network of machines, then it is likely that the internal name of your UUCP machine is not the name you want to use when calling other systems. For example, here at @file{airs.com} our mail/news gateway machine is named @file{elmer.airs.com} (it is one of several machines all named @file{@var{localname}.airs.com}). If we did not provide a @file{config} file, then our UUCP name would be @file{elmer}; however, we actually want it to be @file{airs}. Therefore, we use the following line in @file{config}: @example nodename airs @end example @cindex changing spool directory @cindex spool directory (changing) The UUCP spool directory name is set in @file{policy.h} when the code is compiled. You might at some point decide that it is appropriate to move the spool directory, perhaps to put it on a different disk partition. You might use the following commands in @file{config} to change to directories on the partition @file{/uucp}: @example spool /uucp/spool pubdir /uucp/uucppublic logfile /uucp/spool/Log debugfile /uucp/spool/Debug @end example You would then move the contents of the current spool directory to @file{/uucp/spool}. If you do this, make sure that no UUCP processes are running while you change @file{config} and move the spool directory. @cindex anonymous UUCP Suppose you wanted to permit any system to call in to your system and request files. This is generally known as @dfn{anonymous UUCP}, since the systems which call in are effectively anonymous. By default, unknown systems are not permitted to call in. To permit this you must use the @code{unknown} command in @file{config}. The @code{unknown} command is followed by any command that may appear in the system file; for full details, see @ref{sys file}. I will show two possible anonymous UUCP configurations. The first will let any system call in and download files, but will not permit them to upload files to your system. @example # No files may be transferred to this system unknown request no # The public directory is /usr/spool/anonymous unknown pubdir /usr/spool/anonymous # Only files in the public directory may be sent (the default anyhow) unknown remote-send ~ @end example @noindent Setting the public directory is convenient for the systems which call in. It permits to request a file by prefixing it with @file{~/}. For example, assuming your system is known as @samp{server}, then to retrieve the file @file{/usr/spool/anonymous/INDEX} a user on a remote site could just enter @samp{uucp server!~/INDEX ~}; this would transfer @file{INDEX} from @samp{server}'s public directory to the user's local public directory. Note that when using @samp{csh} or @samp{bash} the @kbd{!} and the second @kbd{~} must be quoted. The next example will permit remote systems to upload files to a special directory @file{/usr/spool/anonymous/upload}. Permitting a remote system to upload files permits it to send work requests as well; this example is careful to prohibit commands from unknown systems. @example # No commands may be executed (the list of permitted commands is empty) unknown commands # The public directory is /usr/spool/anonymous unknown pubdir /usr/spool/anonymous # Only files in the public directory may be sent; users may not download # files from the upload directory unknown remote-send ~ !~/upload # May only upload files into /usr/spool/anonymous/upload unknown remote-receive ~/upload @end example @node Leaf Example, Gateway Example, config File Examples, Configuration Examples @subsection Leaf Example @cindex leaf site @cindex sys file example (leaf) A relatively common simple case is a @dfn{leaf site}, a system which only calls or is called by a single remote site. Here is a typical @file{sys} file that might be used in such a case. For full details on what commands can appear in the @file{sys} file, see @ref{sys file}. This is the @file{sys} file that is used at @file{airs.com}. We use a single modem to dial out to @file{uunet}. This example shows how you can specify the port and dialer information directly in the @file{sys} file for simple cases. It also shows the use of the following: @table @code @item call-login Using @code{call-login} and @code{call-password} allows the default login chat script to be used. In this case, the login name is specified in the call-out login file (@pxref{Configuration File Names}). @item call-timegrade @file{uunet} is requested to not send us news during the daytime. @item chat-fail If the modem returns @samp{BUSY} or @samp{NO CARRIER} the call is immediately aborted. @item protocol-parameter Since @file{uunet} tends to be slow, the default timeout has been increased. @end table This @file{sys} file relies on certain defaults. It will allow @file{uunet} to queue up @samp{rmail} and @samp{rnews} commands. It will allow users to request files from @file{uunet} into the UUCP public directory. It will also @file{uunet} to request files from the UUCP public directory; in fact @file{uunet} never requests files, but for additional security we could add the line @samp{request false}. @example # The following information is for uunet system uunet # The login name and password are kept in the callout password file call-login * call-password * # We can send anything at any time. time any # During the day we only accept grade 'Z' or above; at other times # (not mentioned here) we accept all grades. uunet queues up news # at grade 'd', which is lower than 'Z'. call-timegrade Z Wk0755-2305,Su1655-2305 # The phone number. phone 7389449 # uunet tends to be slow, so we increase the timeout chat-timeout 120 # We are using a preconfigured Telebit 2500. port type modem port device /dev/ttyd0 port baud 19200 port carrier true port dialer chat "" ATZ\r\d\c OK ATDT\D CONNECT port dialer chat-fail BUSY port dialer chat-fail NO\sCARRIER port dialer complete \d\d+++\d\dATH\r\c port dialer abort \d\d+++\d\dATH\r\c # Increase the timeout and the number of retries. protocol-parameter g timeout 20 protocol-parameter g retries 10 @end example @node Gateway Example, , Leaf Example, Configuration Examples @subsection Gateway Example @cindex gateway @cindex sys file example (gateway) Many organizations have several local machines which are connected by UUCP, and a single machine which connects to the outside world. This single machine is often referred to as a @dfn{gateway} machine. For this example I will assume a fairly simple case. It should still provide a good general example. There are three machines, @file{elmer}, @file{comton} and @file{bugs}. @file{elmer} is the gateway machine for which I will show the configuration file. @file{elmer} calls out to @file{uupsi}. As an additional complication, @file{uupsi} knows @file{elmer} as @file{airs}; this will show how a machine can have one name on an internal network but a different name to the external world. @file{elmer} has two modems. It also has an TCP/IP connection to @file{uupsi}, but since that is supposed to be reserved for interactive work (it is, perhaps, only a 9600 baud SLIP line) it will only use it if the modems are not available. A network this small would normally use a single @file{sys} file. However, for pedagogical purposes I will show two separate @file{sys} files, one for the local systems and one for @file{uupsi}. This is done with the @code{sysfile} command in the @file{config} file. Here is the @file{config} file. @example # This is config # The local sys file sysfile /usr/local/lib/uucp/sys.local # The remote sys file sysfile /usr/local/lib/uucp/sys.remote @end example Using the defaults feature of the @file{sys} file can greatly simplify the listing of local systems. Here is @file{sys.local}. Note that this assumes that the local systems are trusted; they are permited to request any world readable file and to write files into any world writable directory. @example # This is sys.local # Get the login name and password to use from the call-out file call-login * call-password * # The systems must use a particular login called-login Ulocal # Permit sending any world readable file local-send / remote-send / # Permit requesting into any world writable directory local-receive / remote-receive / # Call at any time time any # Use port1, then port2 port port1 alternate port port2 # Now define the systems themselves. Because of all the defaults we # used, there is very little to specify for the systems themselves. system comton phone 5551212 system bugs phone 5552424 @end example The @file{sys.remote} file describes the @file{uupsi} connection. The @code{myname} command is used to change the UUCP name to @file{airs} when talking to @file{uupsi}. @example # This is sys.remote # Define uupsi system uupsi # The login name and password are in the call-out file call-login * call-password * # We can call out at any time time any # uupsi uses a special login name called-login Uuupsi # uuspi thinks of us as `airs' myname airs # The phone number phone 5554848 # We use port2 first, then port1, then TCP port port2 alternate port port1 alternate # We don't bother to make a special entry in the port file for TCP, we # just describe the entire port right here. We use a special chat # script over TCP because the usual one confuses some TCP servers. port type TCP address uu.psi.com chat ogin: \L word: \P @end example The ports are defined in the file @file{port} (@pxref{port file}). For this example they are both connected to the same type of 2400 baud Hayes-compatible modem. @example # This is port port port1 type modem device /dev/ttyd0 dialer hayes speed 2400 port port2 type modem device /dev/ttyd1 dialer hayes speed 2400 @end example Dialers are described in the @file{dial} file (@pxref{dial file}). @example # This is dial dialer hayes # The chat script used to dial the phone. \D is the phone number. chat "" ATZ\r\d\c OK ATDT\D CONNECT # If we get BUSY or NO CARRIER we abort the dial immediately chat-fail BUSY chat-fail NO\sCARRIER # When the call is over we make sure we hangup the modem. complete \d\d+++\d\dATH\r\c abort \d\d+++\d\dATH\r\c @end example @node Time Strings, Chat Scripts, Configuration Examples, Configuration Files @section Time Strings @cindex time strings Several commands use time strings to specify a range of times. This section describes how to write time strings. A time string may be a list of simple time strings separated with a vertical bar @kbd{|} or a command @kbd{,}. Each simple time string must begin with @samp{Su}, @samp{Mo}, @samp{Tu}, @samp{We}, @samp{Th}, @samp{Fr}, or @samp{Sa}, or @samp{Wk} for any weekday, or @samp{Any} for any day. Following the day may be a range of hours separated with a hyphen using 24 hour time. The range of hours may cross 0; for example @samp{2300-0700} means any time except 7 AM to 11 PM. If no time is given, calls may be made at any time on the specified day(s). The time string may also consist of the single word @samp{Never}, which does not match any time, or a single word with a name defined in a previous @code{timetable} command (@pxref{Miscellaneous (sys)}). Here are a few sample time strings with an explanation of what they mean. @table @samp @item Wk2305-0855,Sa,Su2305-1655 This means weekdays before 8:55 AM or after 11:05 PM, any time Saturday, or Sunday before 4:55 PM or after 11:05 PM. These are approximately the times during which night rates apply to phone calls in the U.S.A. Note that this time string uses, for example, @samp{2305} rather than @samp{2300}; this will ensure a cheap rate phone call even if the computer clock is running up to five minutes ahead of the real time. @item Wk0905-2255,Su1705-2255 This means weekdays from 9:05 AM to 10:55 PM, or Sunday from 5:05 PM to 10:55 PM. This is approximately the opposite of the previous example. @item Any Since no time is specified, this means any time on any day. @end table @node Chat Scripts, config File, Time Strings, Configuration Files @section Chat Scripts @cindex chat scripts Chat scripts are used in several different places, such as dialing out on modems or logging in to remote systems. Chat scripts are made up of pairs of strings. The program waits until it sees the first string, known as the @dfn{expect} string, and then sends out the second string, the @dfn{send} string. Each chat script is defined using a set of commands. These commands always end in a string beginning with @code{chat}, but may start with different strings. For example, in the @file{sys} file there is one set of commands beginning with @code{chat} and another set beginning with @code{called-chat}. The prefixes are only used to disambiguate different types of chat scripts, and this section ignores the prefixes when describing the commands. @table @code @item chat @var{strings} @findex chat Specify a chat script. The arguments to the @code{chat} command are pairs of strings separated by whitespace. The first string of each pair is an expect string, the second is a send string. The program will wait for the expect string to appear; when it does, the program will send the send string. If the expect string does not appear within a certain number of seconds (as set by the @code{chat-timeout} command) the chat script fails and, typically, the call is aborted. If the final expect string is seen (and the optional final send string has been sent), the chat script is successful. An expect string may contain additional subsend and subexpect strings, separated by hyphens. If the expect string is not seen, the subsend string is sent and the chat script continues by waiting for the subexpect string. This means that a hyphen may not appear in an expect string; use @samp{\055} instead. An expect string may simply be @samp{""}, meaning to skip the expect phase. Otherwise, the following escape characters may appear in expect strings: @table @samp @item \b a backspace character @item \n a newline or line feed character @item \N a null character (for BNU compatibility) @item \r a carriage return character @item \s a space character @item \t a tab character @item \\ a backslash character @item \@var{ddd} character @var{ddd}, where @var{ddd} are up to three octal digits @item \x@var{ddd} character @var{ddd}, where @var{ddd} are hexadecimal digits. @end table As in C, there may be up to three octal digits following a backslash, but the hexadecimal escape sequence continues as far as possible. To follow a hexadecimal escape sequence with a hex digit, interpose a send string of @samp{""}. A send string may also simply be @samp{""} to skip the send phase. Otherwise, all of the escape characters legal for expect strings may be used, and the following escape characters are also permitted: @table @samp @item EOT send an end of transmission character (@kbd{^D}) @item BREAK send a break character (may not work on all systems) @item \c suppress trailing carriage return at end of send string @item \d delay sending for 1 second @item \e disable echo checking @item \E enable echo checking (wait for echo before continuing) @item \K same as @kbd{BREAK} (for BNU compatibility) @item \p pause sending for a fraction of a second @end table Some specific types of chat scripts also define additional escape sequences that may appear in the send string. For example, the login chat script defines @samp{\L} and @samp{\P} to send the login name and password, respectively. A carriage return will be sent at the end of each send string, unless the @kbd{\c} escape sequence appears in the string. Note that some UUCP packages use @kbd{\b} for break, but here it means backspace. Echo checking means that after writing each character the program will wait until the character is echoed. Echo checking must be turned on separately for each send string for which it is desired; it will be turned on for characters following @kbd{\E} and turned off for characters following @kbd{\e}. @item chat-timeout @var{number} @findex chat-timeout The number of seconds to wait for an expect string in the chat script before timing out and sending the next subsend or failing the chat script entirely. The default value is 10 for a login chat or 60 for any other type of chat. @item chat-fail @var{string} @findex chat-fail If the @var{string} is seen at any time during a chat script, the chat script is aborted. The string may not contain any whitespace characters; escape sequences must be used for them. Multiple @code{chat-fail} commands may appear in a single chat script. The default is to have none. This permits a chat script to be quickly aborted if an error string is seen. For example, a script used to dial out on a modem might use the command @samp{chat-fail BUSY} to stop the chat script immediately if the string @samp{BUSY} was seen. @item chat-seven-bit @var{boolean} @findex chat-seven-bit If the argument is true, all incoming characters are stripped to seven bits when being compared to the expect string. Otherwise all eight bits are used in the comparison. The default is true because some Unix systems generate parity bits during the login prompt which must be ignored while running a chat script. This has no effect on any @code{chat-program}, which must ignore parity by itself if necessary. @item chat-program @var{strings} @findex chat-program in sys file Specify a program to run before executing the chat script. This program could run its own version of a chat script, or it could do whatever it wants. If both @code{chat-program} and @code{chat} are specified, the program is executed first followed by the chat script. The first argument to the @code{chat-program} command is the program name to run. The remaining arguments are passed to the program. The following escape sequences are recognized in the arguments: @table @kbd @item \Y port device name @item \S port speed @item \\ backslash @end table Some specific uses of @code{chat-program} define additional escape sequences. Arguments other than escape sequences are passed exactly as they appear in the configuration file, except that sequences of whitespace are compressed to a single space character; this exception may be removed in the future. If the @code{chat-program} command is not used, no program is run. On Unix, the standard input and standard output of the program will be attached to the port in use. Anything the program writes to standard error will be written to the UUCP log file. No other file descriptors will be open. If the program does not exit with a status of 0, it will be assumed to have failed; this means that the dialing programs used by some versions of BNU may not be used directly, although of course a shell script could be used as an interface. The program will be run as the @code{uucp} user, and the environment will be that of the process that started @code{uucico}, so care must be taken to maintain security. No search path is used to find the program; a full path name must be given. If the program is an executable shell script, it will be passed to @file{/bin/sh} even on systems which are unable to execute shell scripts. It is also easy to invoke @file{/bin/sh} directly. @end table Here is a simple example of a chat script that might be used to reset a Hayes compatible modem. @example chat "" ATZ OK-ATZ-OK @end example The first expect string is @samp{""}, so it is ignored. The chat script then sends @samp{ATZ}. If the modem responds with @samp{OK}, the chat script finishes. If 60 seconds (the default timeout) pass before seeing @samp{OK}, the chat script sends another @samp{ATZ}. If it then sees @samp{OK}, the chat script succeeds. Otherwise, the chat script fails. For a more complex chat script example, see @ref{Logging In}. @node config File, sys File, Chat Scripts, Configuration Files @section The Main Configuration File @cindex config file @cindex main configuration file @cindex configuration file (config) The main configuration file is named @file{config}. Since all the values that may be specified in the main configuration file also have defaults, there need not be a main configuration file at all. @menu * Miscellaneous (config):: Miscellaneous config file commands * Configuration File Names:: Using different configuration files * Log File Names:: Using different log files * Debugging Levels:: Debugging levels @end menu @node Miscellaneous (config), Configuration File Names, config File, config File @subsection Miscellaneous config File Commands @table @code @item nodename @var{string} @findex nodename @itemx hostname @var{string} @findex hostname @itemx uuname @var{string} @findex uuname @cindex UUCP system name @cindex system name These keywords are equivalent. They specify the UUCP name of the local host. If there is no configuration file, an appropriate function will be used to get the host name, if possible. @item spool @var{string} @findex spool @cindex spool directory @cindex /usr/spool/uucp Specify the spool directory. The default is from @file{policy.h}. Command files, work files, temporary files, etc., are stored in this directory and in subdirectories of it. @item pubdir @var{string} @findex pubdir in config file @cindex public directory @cindex uucppublic @cindex /usr/spool/uucppublic Specify the public directory. The default is from @file{policy.h}. On Unix, when a file is named using a leading @kbd{~/}, it is taken from or to the public directory. Each system may use a separate public directory by using the @code{pubdir} command in the system configuration file; see @ref{Miscellaneous (sys)}. @item unknown @var{string} @dots{} @findex unknown @cindex unknown systems The @var{string} and subsequent arguments are treated as though they appeared in the system file (@pxref{sys file}). They are used to apply to any unknown systems that may call in, probably to set file transfer permissions and the like. If the @code{unknown} command is not used, unknown systems are not permitted to call in. @item max-uuxqts @var{number} @findex max-uuxqts Specify the maximum number of @code{uuxqt} processes which may run at the same time. Having several @code{uuxqt} processes running at once can significantly slow down a system, but since @code{uuxqt} is automatically started by @code{uucico}, it can happen quite easily. The default for @code{max-uuxqts} is 0, which means that there is no limit. If BNU configuration files are being read and the code was compiled without @code{HAVE_TAYLOR_CONFIG}, then if the file @file{Maxuuxqts} in the configuration directory contains a readable number it will be used as the value for @code{max-uuxqts}. @item v2-files @var{boolean} @findex v2-files If the code was compiled to be able to read V2 configuration files, a false argument to this command will prevent them from being read. This can be useful while testing. The default is true. @item bnu-files @var{boolean} @findex bnu-files If the code was compiled to be able to read BNU configuration files, a false argument to this command will prevent them from being read. This can be useful while testing. The default is true. @end table @node Configuration File Names, Log File Names, Miscellaneous (config), config File @subsection Configuration File Names @table @code @item sysfile @var{strings} @findex sysfile Specify the system file(s). The default is the file @file{sys} in the directory @var{newconfigdir}. These files hold information about other systems with which this system communicates; see @ref{sys file}. Multiple system files may be given on the line, and the @code{sysfile} command may be repeated; each system file has its own set of defaults. @item portfile @var{strings} @findex portfile Specify the port file(s). The default is the file @file{port} in the directory @var{newconfigdir}. These files describe ports which are used to call other systems and accept calls from other systems; see @ref{port file}. No port files need be named at all. Multiple port files may be given on the line, and the @code{portfile} command may be repeated. @item dialfile @var{strings} @findex dialfile Specify the dial file(s). The default is the file @file{dial} in the directory @var{newconfigdir}. These files describe dialing devices (modems); @xref{dial file}. No dial files need be named at all. Multiple dial files may be given on the line, and the @code{dialfile} command may be repeated. @item dialcodefile @var{strings} @findex dialcodefile @cindex configuration file (dialcode) @cindex dialcode file @cindex dialcode configuration file Specify the dialcode file(s). The default is the file @file{dialcode} in the directory @var{newconfigdir}. These files specify dialcodes that may be used when sending phone numbers to a modem. This permits using the same set of phone numbers in different area-codes or with different phone systems, by using dialcodes to specify the calling sequence. When a phone number goes through dialcode translation, the leading alphabetic characters are stripped off. The dialcode files are read line by line, just like any other configuration file, and when a line is found whose first word is the same as the leading characters from the phone number, the second word on the line (which would normally consist of numbers) replaces the dialcode in the phone number. No dialcode file need be used. Multiple dialcode files may be specified on the line, and the @code{dialcodefile} command may be repeated; all the dialcode files will be read in turn until a dialcode is located. @item callfile @var{strings} @findex callfile @cindex call out file @cindex call configuration file @cindex call out login name @cindex call out password @cindex configuration file (call) Specify the call out login name and password file(s). The default is the file @file{call} in the directory @var{newconfigdir}. If the call out login name or password for a system are given as @kbd{*} (@pxref{Logging In}), these files are read to get the real login name or password. Each line in the file(s) has three words: the system name, the login name, and the password. This file is only used when placing calls to remote systems; the password file described under @code{passwdfile} below is used for incoming calls. The intention of the call out file is to permit the system file to be publically readable; the call out files must obviously be kept secure. These files need not be used. Multiple call out files may be specified on the line, and the @code{callfile} command may be repeated; all the files will be read in turn until the system is found. @item passwdfile @var{strings} @findex passwdfile @cindex passwd file @cindex passwd configuration file @cindex configuration file (passwd) @cindex call in login name @cindex call in password Specify the password file(s) to use for login names when @code{uucico} is doing its own login prompting, which it does when given the @samp{-e}, @samp{-l} or @samp{-w} switch. The default is the file @file{passwd} in the directory @var{newconfigdir}. Each line in the file(s) has two words: the login name and the password (e.g. @code{Ufoo foopas}). The login name is accepted before the system name is known, so these are independent of which system is calling in; a particular login may be required for a system by using the @code{called-login} command in the system file (@pxref{Accepting a Call}). These password files are optional, although one must exist if @code{uucico} is to present its own login prompts. Multiple password files may be specified on the line, and the @code{passwdfile} command may be repeated; all the files will be read in turn until the login name is found. @end table @node Log File Names, Debugging Levels, Configuration File Names, config File @subsection Log File Names @table @code @item logfile @var{string} @findex logfile @cindex log file Name the log file. The default is from @file{policy.h}. Logging information is written to this file. If @code{HAVE_BNU_LOGGING} is defined in @file{conf.h}, then by default a separate log file is used for each system. Using this command to name a log file will cause all the systems to use it. @item statfile @var{string} @findex statfile @cindex statistics file Name the statistics file. The default is from @file{policy.h}. Statistical information about file transfers is written to this file. @item debugfile @var{string} @findex debugfile @cindex debugging file Name the file to which debugging information is written. The default is from @file{policy.h}. This command is only effective if the code has been compiled to include debugging (this is controlled by the @code{DEBUG} variable in @file{policy.h}). After the first debugging message has been written, messages written to the log file are also written to the debugging file to make it easier to keep the order of actions straight. The debugging file is different from the log file because information such as passwords can appear in it, so it must be not be publically readable. @end table @node Debugging Levels, , Log File Names, config File @subsection Debugging Levels @table @code @item debug @var{string} @dots{} @findex debug in config file Set the debugging level. This command is only effective if the code has been compiled to include debugging. The default is to have no debugging. The arguments are strings which name the types of debugging to be turned on. The following types of debugging are defined: @table @samp @item abnormal Output debugging messages for abnormal situations, such as recoverable errors. @item chat Output debugging messages for chat scripts. @item handshake Output debugging messages for the initial handshake. @item uucp-proto Output debugging messages for the UUCP protocol itself. @item proto Output debugging messages for the individual protocols. @item port Output debugging messages for actions on the communication port. @item config Output debugging messages while reading the configuration files. @item spooldir Output debugging messages for actions in the spool directory. @item execute Output debugging messages whenever another program is executed. @item incoming List all incoming data in the debugging file. @item outgoing List all outgoing data in the debugging file. @item all All of the above. @end table The debugging level may also be specified as a number. A 1 will set @samp{chat} debugging, a 2 will set both @samp{chat} and @samp{handshake} debugging, and so on down the possibilities. Currently an 11 will turn on all possible debugging, since there are 11 types of debugging messages listed above; more debugging types may be added in the future. The @code{debug} command may be used several times in the configuration file; every debugging type named will be turned on. When running any of the programs, the @samp{-x} switch (actually, for @code{uulog} it's the @samp{-X} switch) may be used to turn on debugging. The argument to the @samp{-x} switch is one of the strings listed above, or a number as described above, or a comma separated list of strings (e.g. @samp{-x chat,handshake}). The @samp{-x} switch may also appear several times on the command line, in which case all named debugging types will be turned on. The @samp{-x} debugging is in addition to any debugging specified by the @code{debug} command; there is no way to cancel debugging information. The debugging level may also be set specifically for calls to or from a specific system with the @code{debug} command in the system file (@pxref{Miscellaneous (sys)}). The debugging messages are somewhat idiosyncratic; it may be necessary to refer to the source code for additional information in some cases. @end table @node sys File, port File, config File, Configuration Files @section The System Configuration File @cindex sys file @cindex system configuration file @cindex configuration file (sys) By default there is a single system configuration, named @file{sys} in the directory @var{newconfigdir}. This may be overridden by the @code{sysfile} command in the main configuration file; see @ref{Configuration File Names}. These files describe all remote systems known to the UUCP package. @menu * Defaults and Alternates:: Using defaults and alternates * Naming the System:: Naming the system * Calling Out:: Calling out * Accepting a Call:: Accepting a call * Protocol Selection:: Protocol selection * File Transfer Control:: File transfer control * Miscellaneous (sys):: Miscellaneous sys file commands * Default sys File Values:: Default values @end menu @node Defaults and Alternates, Naming the System, sys File, sys File @subsection Defaults and Alternates The first set of commands in the file, up to the first @code{system} command, specify defaults to be used for all systems in that file. Each system file uses a different set of defaults. Subsequently, each set of commands from @code{system} up to the next @code{system} command describe a particular system. Default values may be overridden for specific systems. Each system may then have a series of alternate choices to use when calling out or calling in. The first set of commands for a particular system, up to the first @code{alternate} command, provide the first choice. Subsequently, each set of commands from @code{alternate} up to the next @code{alternate} command describe an alternate choice for calling out or calling in. When a system is called, the commands before the first @code{alternate} are used to select a phone number, port, and so forth; if the call fails for some reason, the commands between the first @code{alternate} and the second are used, and so forth. Well, not quite. Actually, each succeeding alternate will only be used if it is different in some relevant way (different phone number, different chat script, etc.). If you want to force the same alternate to be used again (to retry a phone call more than once, for example), enter the phone number (or any other relevant field) again to make it appear different. The alternates can also be used to give different permissions to an incoming call based on the login name. This will only be done if the first set of commands, before the first @code{alternate} command, uses the @code{called-login} command. The list of alternates will be searched, and the first alternate with a matching @code{called-login} command will be used. If no alternates match, the call will be rejected. The @code{alternate} command may also be used in the file-wide defaults (the set of commands before the first @code{system} command). This might be used to specify a list of ports which are available for all systems (for an example of this, see @ref{Gateway Example}) or to specify permissions based on the login name used by the remote system when it calls in. The first alternate for each system will default to the first alternate for the file-wide defaults (as modified by the commands used before the first @code{alternate} command for this system), the second alternate for each system to the second alternate for the file-wide defaults (as modified the same way), and so forth. If a system specifies more alternates than the file-wide defaults, the trailing ones will default to the last file-wide default alternate. If a system specifies fewer alternates than the file-wide defaults, the trailing file-wide default alternates will be used unmodified. The @code{default-alternates} command may be used to modify this behaviour. This can all get rather confusing, although it's easier to use than to describe concisely; the @code{uuchk} program may be used to ensure that you are getting what you want. @node Naming the System, Calling Out, Defaults and Alternates, sys File @subsection Naming the System @table @code @item system @var{string} @findex system Specify the remote system name. Subsequent commands up to the next @code{system} command refer to this system. @item alternate [@var{string}] @findex alternate Start an alternate set of commands (@pxref{Defaults and Alternates}). An optional argument may be used to name the alternate. This name will be put in the log file if the alternate is used to call the system. There is no way to name the first alternate (the commands before the first @code{alternate} command). @item default-alternates @var{boolean} @findex default-alternates If the argument is false, any remaining default alternates (from the defaults specified at the top of the current system file) will not be used. The default is true. @item alias @var{string} @findex alias Specify an alias for the current system. The alias may be used by local @code{uucp} and @code{uux} commands. The default is to have no aliases. @item myname @var{string} @findex myname Specifies a different system name to use when calling the remote system. Also, if @code{called-login} is used and is not @samp{ANY}, then, when a system logs in with that login name, @var{string} is used as the system name. Because the local system name must be determined before the remote system has identified itself, using @code{myname} and @code{called-login} together for any system will set the local name for that login; this means that each locally used system name must have a unique login name associated with it. This allows a system to have different names for an external and an internal network. The default is to not use a special local name. @end table @node Calling Out, Accepting a Call, Naming the System, sys File @subsection Calling Out This section describes commands used when placing a call to another system. @menu * When to Call:: When to call * Placing the Call:: Placing the call * Logging In:: Logging in @end menu @node When to Call, Placing the Call, Calling Out, Calling Out @subsubsection When to Call @table @code @item time @var{string} [@var{number}] @findex time Specify when the system may be called. The first argument is a time string; see @ref{Time Strings}. The optional second argument specifies a retry time in minutes. If a call made during a time that matches the time string fails, no more calls are permitted until the retry time has passed. By default an exponentially increasing retry time is used: after each failure the next retry period is longer. A retry time specified in the @code{time} command is always a fixed amount of time. The @code{time} command may appear multiple times in a single alternate, in which case if any time string matches the system may be called. The default time string is @samp{Never}. @item timegrade @var{character} @var{string} [@var{number}] @findex timegrade The @var{character} specifies a grade. It must be a single letter or digit. The @var{string} is a time string (@pxref{Time Strings}). All jobs of grade @var{character} or higher (where @kbd{0} > @kbd{9} > @kbd{A} > @kbd{Z} > @kbd{a} > @kbd{z}) may be run at the specified time. An ordinary @code{time} command is equivalent to using @code{timegrade} with a grade of @kbd{z}, permitting all jobs. If there are no jobs of a sufficiently high grade according to the time string, the system will not be called. Giving the @samp{-s} switch to @code{uucico} to force it to call a system causes it to assume there is a job of grade @kbd{0} waiting to be run. The optional third argument specifies a retry time in minutes. See the @code{time} command, above, for more details. Note that the @code{timegrade} command serves two purposes: 1) if there is no job of sufficiently high grade the system will not be called, and 2) if the system is called anyway (because the @samp{-s} switch was given to @code{uucico}) only jobs of sufficiently high grade will be transferred. However, if the other system calls in, the @code{timegrade} commands are ignored, and jobs of any grade may be transferred (but see @code{call-timegrade} below). Also, the @code{timegrade} command will not prevent the other system from transferring any job it chooses, regardless of who placed the call. The @code{timegrade} command may appear multiple times without using @code{alternate}. If this command does not appear, there are no restrictions on what grade of work may be done at what time. @item call-timegrade @var{character} @var{string} @findex call-timegrade The @var{character} is a single character @kbd{A} to @kbd{Z}, @kbd{a} to @kbd{z}, or @kbd{0} to @kbd{9} and specifies a grade. The @var{string} is a time string as described under the @code{time} command. If a call is placed to the other system during a time which matches the time string, the remote system will be requested to only run jobs of grade @var{character} or higher. Unfortunately, there is no way to guarantee that the other system will obey the request (this UUCP package will, but there are others which will not); moreover job grades are historically somewhat arbitrary, so specifying a grade will only be meaningful if the other system cooperates in assigning grades. This grade restriction only applies when the other system is called, not when the other system calls in. The @code{call-timegrade} command may appear multiple times without using @code{alternate}. If this command does not appear, or if none of the time strings match, the remote system will be allowed to send whatever grades of work it chooses. @end table @node Placing the Call, Logging In, When to Call, Calling Out @subsubsection Placing the Call @table @code @item baud @var{number} @findex baud in sys file @itemx speed @var{number} @findex speed in sys file Specify the speed (the term @dfn{baud} is technically incorrect, but widely understood) at which to call the system. This will try all available ports with that baud rate until an unlocked port is found. The ports are defined in the port file. If both @code{baud} and @code{port} commands appear, both are used when selecting a port. To allow calls at more than one baud rate, the @code{alternate} command must be used (@pxref{Defaults and Alternates}). If this command does not appear, there is no default; the baud rate may be specified in the port file, but if it is not then the natural baud rate of the port will be used (whatever that means on the system). Specifying an explicit baud rate of 0 will request the natural baud rate of the port, overriding any default baud rate from the defaults at the top of the file. @item port @var{string} @findex port in sys file Name a particular port or type of port to use when calling the system. The information for this port is obtained from the port file. If this command does not appear, there is no default; a port must somehow be specified in order to call out (it may be specified implicitly using the @code{baud} command or explicitly using the next version of @code{port}). There may be many ports with the same name; each will be tried in turn until an unlocked one is found which matches the desired baud rate. @item port @var{string} @dots{} If more than one string follows the @code{port} command, the subsequent strings are treated as commands that might appear in the port file (@pxref{port file}). If a port is named (by using a single string following @code{port}) these commands are ignored; their purpose is to permit defining the port completely in the system file rather than always requiring entries in two different files. In order to call out, a port must be specified using some version of the @code{port} command, or by using the @code{baud} command to select ports from the port file. @item phone @var{string} @findex phone @itemx address @var{string} @findex address Give a phone number to call (when using a modem port) or a remote host to contact (when using a TCP port). The commands @code{phone} and @code{address} are equivalent, but are intended to be more mnemonic depending on the type of port in use. When used with a modem port, an @kbd{=} character in the phone number means to wait for a secondary dial tone (although only some modems support this); a @kbd{-} character means to pause while dialing for 1 second (again, only some modems support this). If the system has more than one phone number, each one must appear in a different alternate. The @code{phone} command must appear in order to call out on a modem; there is no default. When used with a TCP port, the string names the host to contact. It may be a domain name or a numeric Internet address. If no address is specified, the system name is used. When used with a port that neither is a modem nor TCP, this command is ignored. @end table @node Logging In, , Placing the Call, Calling Out @subsubsection Logging In @table @code @item chat @var{strings} @findex chat in sys file @item chat-timeout @var{number} @findex chat-timeout in sys file @item chat-fail @var{string} @findex chat-fail in sys file @item chat-seven-bit @var{boolean} @findex chat-seven-bit in sys file @item chat-program @var{strings} @findex chat-program in sys file These commands describe a chat script to use when logging on to a remote system. Chat scripts are explained in @ref{Chat Scripts}. Two additional escape sequences may be used in send strings. @table @samp @item \L Send the login name, as set by the @code{call-login} command. @item \P Send the passowrd, as set by the @code{call-password} command. @end table Three additional escape sequences may be used with the @code{chat-program} command. These are @samp{\L} and @samp{\P}, which become the login name and password, respectively, and @samp{\Z}, which becomes the name of the system of being called. The default chat script is: @example chat "" \r\c ogin:-BREAK-ogin:-BREAK-ogin: \L word: \P @end example This will send a carriage return (the @kbd{\c} suppresses the additional trailing carriage return that would otherwise be sent) and waits for the string @samp{ogin:} (which would be the last part of the @samp{login:} prompt supplied by a Unix system). If it doesn't see @samp{ogin:}, it sends a break and waits for @samp{ogin:} again. If it still doesn't see @samp{ogin:}, it sends another break and waits for @samp{ogin:} again. If it still doesn't see @samp{ogin:}, the chat script aborts and hangs up the phone. If it does see @samp{ogin:} at some point, it sends the login name (as specified by the @code{call-login} command) followed by a carriage return (since all send strings are followed by a carriage return unless @kbd{\c} is used) and waits for the string @samp{word:} (which would be the last part of the @samp{Password:} prompt supplied by a Unix system). If it sees @samp{word:}, it sends the password and a carriage return, completing the chat script. The program will then enter the handshake phase of the UUCP protocol. This chat script will work for most systems, so you will only be required to use the @code{call-login} and @code{call-password} commands. In fact, in the file-wide defaults you could set defaults of @samp{call-login *} and @samp{call-password *}; you would then just have to make an entry for each system in the call-out login file. Some systems seem to flush input after the @samp{login:} prompt, so they may need a version of this chat script with a @kbd{\d} before the @kbd{\L}. When using UUCP over TCP, some servers will not be handle the initial carriage return sent by this chat script; in this case you may have to specify the simple chat script @samp{ogin: \L word: \P}. @item call-login @var{string} @findex call-login Specify the login name to send with @kbd{\L} in the chat script. If the string is @samp{*} (e.g. @samp{call-login *}) the login name will be fetched from the call out login name and password file (@pxref{Configuration File Names}). There is no default. @item call-password @var{string} @findex call-password Specify the password to send with @kbd{\P} in the chat script. If the string is @samp{*} (e.g. @samp{call-password *}) the password will be fetched from the call-out login name and password file (@pxref{Configuration File Names}). There is no default. @end table @node Accepting a Call, Protocol Selection, Calling Out, sys File @subsection Accepting a Call @table @code @item called-login @var{strings} @findex called-login The first @var{string} specifies the login name that the system must use when calling in. If it is @samp{ANY} (e.g. @samp{called-login ANY}) any login name may be used; this is useful to override a file-wide default and to indicate that future alternates may have different login names. Case is significant. The default value is @samp{ANY}. Different alternates (@pxref{Defaults and Alternates}) may use different @code{called-login} commands, in which case the login name will be used to select which alternate is in effect; this will only work if the first alternate (before the first @code{alternate} command) uses the @code{called-login} command. Additional strings may be specified after the login name; they are a list of which systems are permitted to use this login name. If this feature is used, then normally the login name will only be given in a single @code{called-login} command. Only systems which appear on the list, or which use an explicit @code{called-login} command, will be permitted to use that login name. If the same login name is used more than once with a list of systems, all the lists are concatenated together. This feature permits you to restrict a login name to a particular set of systems without requiring you to use the @code{called-login} command for every single system; you can achieve a similar effect by using a different system file for each permitted login name with an appropriate @code{called-login} command in the file-wide defaults. @item callback @var{boolean} @findex callback If @var{boolean} is true, then when the remote system calls @code{uucico} will hang up the connection and prepare to call it back. This is false by default. @item called-chat @var{strings} @findex called-chat @item called-chat-timeout @var{number} @findex called-chat-timeout @item called-chat-fail @var{string} @findex called-chat-fail @item called-chat-seven-bit @var{boolean} @findex called-chat-seven-bit @item called-chat-program @var{strings} @findex called-chat-program These commands may be used to define a chat script (@pxref{Chat Scripts}) that is run whenever the local system is called by the system being defined. The chat script defined by the @code{chat} command (@pxref{Logging In}), on the other hand, is used when the remote system is called. This called chat script might be used to set special modem parameters that are appropriate to a particular system. It is run after protocol negotiation is complete, but before the protocol has been started. See @ref{Logging In} for additional escape sequence which may be used besides those defined for all chat scripts. There is no default called chat script. If the called chat script fails, the incoming call will be aborted. @end table @node Protocol Selection, File Transfer Control, Accepting a Call, sys File @subsection Protocol Selection @table @code @item protocol @var{string} @findex protocol in sys file Specifies which protocols to use for the other system, and in which order to use them. This would not normally be used. For example, @samp{protocol tfg}. The default depends on the characteristics of the port and the dialer, as specified by the @code{seven-bit} and @code{reliable} commands. If neither the port nor the dialer use either of these commands, the default is to assume an eight-bit reliable connection. The commands @samp{seven-bit true} or @samp{reliable false} might be used in either the port or the dialer to change this. Each protocol has particular requirements that must be met before it will be considered during negotiation with the remote side. The @samp{t} and @samp{e} protocols are intended for use over TCP or some other communication path with end to end reliability, as they do no checking of the data at all. They will only be considered on a TCP port which is both reliable and eight bit. The @samp{g} protocol is robust, but requires an eight-bit connection. The @samp{f} protocol is intended for use with X.25 connections; it checksums each file as a whole, so any error causes the entire file to be retransmitted. It requires a reliable connection, but only uses seven-bit transmissions. It is a streaming protocol, so, while it can be used on a serial port, the port must be completely reliable and flow controlled; many aren't. The protocols will be considered in the order shown above. This means that if neither the @code{seven-bit} nor the @code{reliable} command are used, the @samp{t} protocol will be used over a TCP connection and the @samp{g} protocol will be used over any other type of connection (subject, of course, to what is supported by the remote system; it may be assumed that all systems support the @samp{g} protocol). Note that currently specifying both @samp{seven-bit true} and @samp{reliable false} will not match any protocol. If this occurs through a combination of port and dialer specifications, you will have to use the @code{protocol} command for the system or no protocol will be selected at all (the only reasonable choice would be @samp{protocol f}). A protocol list may also be specified for a port (@pxref{port file}), but if there is a list for the system the list for the port is ignored. @item protocol-parameter @var{character} @var{string} @dots{} @findex protocol-parameter in sys file @var{character} is a single character specifying a protocol. The remaining strings are a command specific to that protocol which will be executed if that protocol is used. A typical command is something like @samp{window 7}. The particular commands are protocol specific. The @samp{g} protocol supports the following commands, all of which take numeric arguments: @table @code @item window The window size to request the remote system to use. This must be between 1 and 7 inclusive. The default is 7. @item packet-size The packet size to request the remote system to use. This must be a power of 2 between 32 and 4096 inclusive. The default is 64, which is the only packet size supported by many older UUCP packages. Some UUCP packages will even dump core if a larger packet size is requested. @item startup-retries The number of times to retry the initialization sequence. The default is 8. @item init-retries The number of times to retry one phase of the initialization sequence (there are three phases). The default is 4. @item init-timeout The timeout in seconds for one phase of the initialization sequence. The default is 10. @item retries The number of times to retry sending either a data packet or a request for the next packet. The default is 6. @item timeout The timeout in seconds when waiting for either a data packet or an acknowledgement. The default is 10. @item garbage The number of unrecognized bytes to permit before dropping the connection. This must be larger than the packet size. The default is 10000. @item errors The number of errors (malformed packets, out of order packets, bad checksums, or packets rejected by the remote system) to permit before dropping the connection. The default is 100. @item remote-window If this is between 1 and 7 inclusive, the window size requested by the remote system is ignored and this is used instead. This can be useful when dealing with some poor UUCP packages. The default is 0, which means that the remote system's request is honored. @item remote-packet-size If this is between 32 and 4096 inclusive the packet size requested by the remote system is ignored and this is used instead. There is probably no good reason to use this. The default is 0, which means that the remote system's request is honored. @end table The @samp{f} protocol is intended for use with error-correcting modems only; it checksums each file as a whole, so any error causes the entire file to be retransmitted. It supports the following commands, both of which take numeric arguments: @table @code @item timeout The timeout in seconds before giving up. The default is 120. @item retries How many times to retry sending a file. The default is 2. @end table The @samp{t} and @samp{e} protocols are intended for use over TCP or some other communication path with end to end reliability, as they do no checking of the data at all. They both support a single command, which takes a numeric argument: @table @code @item timeout The timeout in seconds before giving up. The default is 120. @end table The protocol parameters are reset to their default values after each call. @end table @node File Transfer Control, Miscellaneous (sys), Protocol Selection, sys File @subsection File Transfer Control @table @code @item call-request @var{boolean} @findex call-request The @var{boolean} is checked when the local system places the call. It determines whether the remote system may request any file transfers. The default is yes. @item called-request @var{boolean} @findex called-request The @var{boolean} is checked when the remote system calls in. It determines whether the remote system may request any file transfers. The default is yes. @item request @var{boolean} @findex request Equivalent to specifying both @samp{call-request @var{boolean}} and @samp{called-request @var{boolean}}. @item call-transfer @var{boolean} @findex call-transfer The @var{boolean} is checked when the local system places the call. It determines whether the local system may do file transfers queued up for the remote system. The default is yes. @item called-transfer @var{boolean} @findex called-transfer The @var{boolean} is checked when the remote system calls in. It determines whether the local system may do file transfers queued up for the remote system. The default is yes. @item transfer @var{boolean} @findex transfer Equivalent to specifying both @samp{call-transfer @var{boolean}} @samp{called-transfer @var{boolean}}. @item call-local-size @var{number} @var{string} @findex call-local-size The @var{string} is a time string (@pxref{Time Strings}). The @var{number} is the size in bytes of the largest file that should be transferred at a time matching the time string if the local system placed the call and the request was made by the local system. This command may appear multiple times in a single alternate. If this command does not appear, or if none of the time strings match, there are no size restrictions. With all the size control commands, the size of a file from the remote system (as opposed to a file from the local system) will only be checked if the other system is running this package; other UUCP packages will not understand a maximum size request, nor will they inform this package of the size of remote files. @item call-remote-size @var{number} @var{string} @findex call-remote-size Specify the size in bytes of the largest file that should be transferred at a given time by remote request when the local system placed the call. This command may appear multiple times in a single alternate. If this command does not appear, there are no size restrictions. @item called-local-size @var{number} @var{string} @findex called-local-size Specify the size in bytes of the largest file that should be transferred at a given time by local request when the remote system placed the call. This command may appear multiple times in a single alternate. If this command does not appear, there are no size restrictions. @item called-remote-size @var{number} @var{string} @findex called-remote-size Specify the size in bytes of the largest file that should be transferred at a given time by remote request when the remote system placed the call. This command may appear multiple times in a single alternate. If this command does not appear, there are no size restrictions. @item local-send @var{strings} @findex local-send Specifies that files in the directories named by the @var{strings} may be sent to the remote system when requested locally (using @code{uucp} or @code{uux}). The directories in the list should be separated by whitespace. A @kbd{~} may be used for the public directory. On a Unix system, this is typically @file{/usr/spool/uucppublic}; the public directory may be set with the @code{pubdir} command. Here is an example of @code{local-send}: @example local-send ~ /usr/spool/ftp/pub @end example Listing a directory allows all files within the directory and all subdirectories to be sent. Directories may be excluded by preceding them with an exclamation point. For example: @example local-send /usr/ftp !/usr/ftp/private ~ @end example @noindent means that all files in @file{/usr/ftp} or the public directory may be sent, except those files in @file{/usr/ftp/private}. The list of directories is read from left to right, and the last directory to apply takes effect; this means that directories should be listed from top down. The default is the root directory (i.e., any file at all may be sent by local request). @item remote-send @var{strings} @findex remote-send Specifies that files in the named directories may be sent to the remote system when requested by the remote system. The default is @kbd{~}. @item local-receive @var{strings} @findex local-receive Specifies that files may be received into the named directories when requested by a local user. The default is @kbd{~}. @item remote-receive @var{strings} @findex remote-receive Specifies that files may be received into the named directories when requested by the remote system. The default is @kbd{~}. On Unix, the remote system may only request that files be received into directories that are writeable by the world, regardless of how this is set. @end table @node Miscellaneous (sys), Default sys File Values, File Transfer Control, sys File @subsection Miscellaneous sys File Commands @table @code @item sequence @var{boolean} @findex sequence If @var{boolean} is true, then conversation sequencing is automatically used for the remote system, so that if somebody manages to spoof as the remote system, it will be detected the next time the remote system actually calls. This is false by default. @item command-path @var{string} @findex command-path Specifies the path (a list of whitespace separated directories) to be searched to locate commands to execute. This is only used for commands requested by @code{uux}, not for chat programs. The default is from @file{policy.h}. @item commands @var{strings} @findex commands The list of commands which the remote system is permitted to execute locally. For example: @samp{commands rnews rmail}. If the value is @samp{ALL} (case significant), all commands may be executed. The default is @samp{rnews rmail}. @item free-space @var{number} @findex free-space Specify the minimum amount of file system space (in bytes) to leave free after receiving a file. If the incoming file will not fit, it will be rejected. This will only work when talking to another instance of this package, since older UUCP packages do not provide the file size of incoming files. There is no provision for reserving space, so it is still possible for multiple @code{uucico} daemons to use up all available file space; a sufficiently large value for @code{free-space} will avoid this problem to some extent. The default is from @file{policy.h}. Not all systems may be able to provide the amount of available space. @item pubdir @var{string} @findex pubdir in sys file Specifies the public directory that is used when @kbd{~} is specifed in a file transfer or a list of directories. This essentially overrides the public directory specified in the main configuration file for this system only. The default is the public directory specified in the main configuration file (which defaults to a value from @file{policy.h}). @item debug @var{string} @dots{} @findex debug in sys file Set additional debugging for calls to or from the system. This may be used to debug a connection with a specific system. It is particularly useful when debugging incoming calls, since debugging information will be generated whenever the call comes in. See the @code{debug} command in the main configuration file (@pxref{Debugging Levels}) for more details. The debugging information specified here is in addition to that specified in the main configuration file or on the command line. @item max-remote-debug @var{string} @dots{} @findex max-remote-debug When the system calls in, it may request that the debugging level be set to a certain value. This command may be used to put a limit on the debugging level which the system may request, to avoid filling up the disk with debugging information. Only the debugging types named in the @code{max-remote-debug} command may be turned on by the remote system. To prohibit any debugging, use @samp{max-remote-debug none}. The default is @samp{abnormal,chat,handshake}; to turn off these default entries, you must use @samp{max-remote-debug none} followed by other @code{max-remote-debug} commands specifying the settings you want. @item timetable @var{string} @var{string} @findex timetable This is actually not specific to a system; it can appear anywhere in the file(s). In a future release this command will probably be moved to the main configuration file. The @code{timetable} defines a timetable that may be used in subsequently appearing time strings; @ref{Time Strings}. The first string names the timetable entry; the second is a time string. The following @code{timetable} commands are predefined. The NonPeak timetable is included for compatibility. It originally described the offpeak hours of Tymnet and Telenet, but both have since changed their schedules. @example timetable Evening Wk1705-0755,Sa,Su timetable Night Wk2305-0755,Sa,Su2305-1655 timetable NonPeak Wk1805-0655,Sa,Su @end example If this command does not appear, then obviously no additional timetables will be defined. @end table @node Default sys File Values, , Miscellaneous (sys), sys File @subsection Default sys File Values The following are used as default values for all systems; they can be considered as appearing before the start of the file. @example timetable Evening Wk1705-0755,Sa,Su timetable Night Wk2305-0755,Sa,Su2305-1655 timetable NonPeak Wk1805-0655,Sa,Su time Never chat "" \r\c ogin:-BREAK-ogin:-BREAK-ogin: \L word: \P chat-timeout 10 callback n sequence n request y transfer y local-send / remote-send ~ local-receive ~ remove-receive ~ command-path [ from @file{policy.h} ] commands rnews rmail max-remote-debug abnormal,chat,handshake @end example @node port File, dial File, sys File, Configuration Files @section The Port Configuration File @cindex port file @cindex port configuration file @cindex configuration file (port) The port files may be used to name and describe ports. The first command in each file must be @code{port}. All command up to the next @code{port} command then describe that port. There are different types of ports; each type supports its own set of commands. Each command indicates which types of ports support it. There may be many ports with the same name; if a system requests a port by name then each port with that name will be tried until an unlocked one is found. @table @code @item port @var{string} @findex port in port file Introduces and names a port. @item type @var{string} @findex type Define the type of port. The default is @samp{modem}. If this command appears, it must immediately follow the @code{port} command. The type defines what commands are subsequently allowed. Currently the types are: @table @samp @item modem For a modem hookup. @item stdin For a connection through standard input and standard output, as when @code{uucico} is run as a login shell. @item direct For a direct connection to another system. @item tcp For a connection using TCP. @end table @item protocol @var{string} @findex protocol in port file Specify a list of protocols to use for this port. This is just like the corresponding command for a system (@pxref{Protocol Selection}). A protocol list for a system takes precedence over a list for a port. @item protocol-parameter @var{character} @var{strings} [ any type ] @findex protocol-parameter in port file The same command as the @code{protocol-parameter} command used for systems (@pxref{Protocol Selection}). This one takes precedence. @item seven-bit @var{boolean} [ any type ] @findex seven-bit in port file This is only used during protocol negotiation; if the argument is @samp{true}, it forces the selection of a protocol which works across a seven-bit link. It does not prevent eight bit characters from being transmitted. The default is @samp{false}. @item reliable @var{boolean} [ any type ] @findex reliable in port file This is only used during protocol negotiation; if the argument is @samp{false}, it forces the selection of a protocol which works across an unreliable communication link. The default is @samp{true}. It would be more common to specify this for a dialer rather than a port. @item device @var{string} [ modem and direct only ] @findex device Names the device associated with this port. If the device is not named, the port name is taken as the device. Device names are system dependent, but a Unix example would be @file{/dev/ttyd0}. @item baud @var{number} [ modem and direct only ] @findex baud in port file @itemx speed @var{number} [modem and direct only ] @findex speed in port file The speed this port runs at. If a system specifies a speed but no port name, then all ports which match the speed will be tried in order. If the speed is not specified here and is not specified by the system, the natural speed of the port will be used by default. @item baud-range @var{number} @var{number} [ modem only ] @findex baud-range @itemx speed-range @var{number} @var{number} [ modem only ] @findex speed-range Specify a range of speeds this port can run at. The first number is the minimum speed, the second number is the maximum speed. These numbers will be used when matching a system which specifies a desired speed. The simple @code{speed} (or @code{baud}) command is still used to determine the speed to run at if the system does not specify a speed. For example, the command @samp{speed-range 300 19200} means that the port will match any system which uses a speed from 300 to 19200 baud (and will use the speed specified by the system); this could be combined with @samp{speed 2400}, which means that when this port is used with a system that does not specify a speed, the port will be used at 2400 baud. @item carrier @var{boolean} [ modem only ] @findex carrier in port file The argument indicates whether the port supports carrier. If it does not, carrier will never be required on this port, regardless of what the modem chat script indicates. The default is @samp{true}. @item dial-device @var{string} [ modem only ] @findex dial-device Dialing instructions should be output to the named device, rather than to the normal port device. The default is to output to the normal port device. @item dialer @var{string} [ modem only ] @findex dialer in port file Name a dialer to use. The information is looked up in the dialer file. There is no default. Some sort of dialer information must be specified to call out on a modem. @item dialer @var{string} @dots{} [ modem only ] Execute a dialer command. If a dialer is named (by using the first form of this command, described just above), these commands are ignored. They may be used to specify dialer information directly in simple situations without needing to go to a separate file. There is no default. Some sort of dialer information must be specified to call out on a modem. @item dialer-sequence @var{strings} [ modem only ] @findex dialer-sequence Name a sequence of dialers and tokens (phone numbers) to use. The first argument names a dialer, and the second argument names a token. The third argument names another dialer, and so on. If there are an odd number of arguments, the phone number specified with a @code{phone} command in the system file is used as the final token. The token is what is used for @kbd{\D} or @kbd{\T} in the dialer chat script. If the token in this string is @kbd{\D}, the system phone number will be used; if it is @kbd{\T}, the system phone number will be used after undergoing dialcodes translation. A missing final token is taken as @kbd{\D}. This command currently does not work if @code{dial-device} is specified; to handle this correctly will require a more systematic notion of chat scripts. Moreover, only the @code{complete} and @code{abort} chat scripts from the first dialer specified are used, and only the protocol parameters from the first dialer are used. @item lockname @var{string} [ modem and direct only ] @findex lockname Give the name to use when locking this port. On Unix, this is the name of the file that will be created in the lock directory. It is used as is, so on Unix it should generally start with @samp{LCK..}. For example, if a single port were named both @file{/dev/ttycu0} and @file{/dev/tty0} (perhaps with different characteristics keyed on the minor device number), then the command @code{lockname LCK..ttycu0} could be used to force the latter to use the same lock file name as the former. @item service @var{string} [ tcp only ] @findex service Name the TCP port number to use. This may be a number. If not, it will be looked up in @file{/etc/services}. If this is not specified, the string @samp{uucp} is looked up in @file{/etc/services}. If it is not found, port number 540 (the standard UUCP-over-TCP port number) will be used. @end table @node dial File, Security, port File, Configuration Files @section The Dialer Configuration File @cindex dial file @cindex dialer configuration file @cindex configuration file (dial) The dialer configuration files define dialers. The first command in each file must be a @code{dialer} command, which names the dialer. Subsequent commands up to the next @code{dialer} command are associated with the named dialer. @table @code @item dialer @var{string} @findex dialer in dial file Introduces and names a dialer. @item chat @var{strings} @findex chat in dial file @item chat-timeout @var{number} @findex chat-timeout in dial file @item chat-fail @var{string} @findex chat-fail in dial file @item chat-seven-bit @var{boolean} @findex chat-seven-bit in dial file @item chat-program @var{strings} @findex chat-program in dial file Specify a chat script to be used to dial the phone. See @ref{Chat Scripts} for full details on chat scripts. Taylor UUCP will sleep for one second between attempts to dial out on a modem. If your modem requires a longer wait period, you must start your chat script with delays (@samp{\d} in a send string). The chat script will be read from and sent to the port specified by the @code{dial-device} command for the port, if there is one. The following escape addition escape sequences may appear in send strings: @table @kbd @item \D send phone number without dialcode translation @item \T send phone number with dialcode translation @item \M do not require carrier @item \m require carrier (fail if not present) @end table See the description of the dialcodes file (@pxref{Configuration File Names}) for a description of dialcode translation. If the port does not support carrier (as set by the @code{carrier} command in the port file) @kbd{\M} and @kbd{\m} are ignored. If both the port and the dialer support carrier (as set by the @code{carrier} command in the port file and the @code{carrier} command in the dialer file), then every chat script implicitly begins with @kbd{\M} and ends with @kbd{\m}. There is no default chat script for dialers. The following additional escape sequences may be used in @code{chat-program}: @table @kbd @item \D phone number without dialcode translation @item \T phone number with dialcode translation @end table If the program changes the port in any way (e.g., sets parity) the changes will be preserved during protocol negotiation, but once the protocol is selected it will change the port settings. @item dialtone @var{string} @findex dialtone A string to output when dialing the phone number which causes the modem to wait for a secondary dial tone. This is used to translate the @kbd{=} character in a phone number. The default is a comma. @item pause @var{string} @findex pause A string to output when dialing the phone number which causes the modem to wait for 1 second. This is used to translate the @kbd{-} character in a phone number. The default is a comma. @item carrier @var{boolean} @findex carrier in dial file If the argument is @samp{true}, the dialer supports the modem carrier signal. After the phone number is dialed, @code{uucico} will require that carrier be on. One some systems, it will be able to wait for it. If the argument is @samp{false}, carrier will not be required. The default is @samp{true}. @item carrier-wait @var{number} @findex carrier-wait If the port is supposed to wait for carrier, this may be used to indicate how many seconds to wait. The default is 60 seconds. Only some systems support waiting for carrier. @item dtr-toggle @var{boolean} @var{boolean} @findex dtr-toggle If the first argument is @samp{true}, then DTR is toggled before using the modem. This is only supported on some systems and some ports. The second @var{boolean} need not be present; if it is, and it is @samp{true}, the program will sleep for 1 second after toggling DTR. The default is not to toggle DTR. @item complete-chat @var{strings} @findex complete-chat @item complete-chat-timeout @var{number} @findex complete-chat-timeout @item complete-chat-fail @var{string} @findex complete-chat-fail @item complete-chat-seven-bit @var{boolean} @findex complete-chat-seven-bit @item complete-chat-program @var{strings} @findex complete-chat-program These commands define a chat script (@pxref{Chat Scripts}) which is run when a call is finished normally. This allows the modem to be reset. There is no default. No additional escape sequences may be used. @item complete @var{string} @findex complete This is a simple use of @code{complete-chat}. It is equivalent to @code{complete-chat "" @var{string}}; this has the effect of sending @var{string} to the modem when a call finishes normally. @item abort-chat @var{strings} @findex abort-chat @item abort-chat-timeout @var{number} @findex abort-chat-timeout @item abort-chat-fail @var{string} @findex abort-chat-fail @item abort-chat-seven-bit @var{boolean} @findex abort-chat-seven-bit @item abort-chat-program @var{strings} @findex abort-chat-program These commands define a chat script (@pxref{Chat Scripts}) to be run when a call is aborted. They may be used to interrupt and reset the modem. There is no default. No additional escape sequences may be used. @item abort @var{string} @findex abort This is a simple use of @code{abort-chat}. It is equivalent to @code{abort-chat "" @var{string}}; this has the effect of sending @var{string} to the modem when a call is aborted. @item protocol-parameter @var{character} @var{strings} @findex protocol-parameter in dial file Set protocol parameters, just like the @code{protocol-parameter} command in the system configuration file or the port configuration file; see @ref{Protocol Selection}. These parameters take precedence, then those for the port, then those for the system. @item seven-bit @var{boolean} @findex seven-bit in dial file This is only used during protocol negotiation; if it is @samp{true}, it forces selection of a protocol which works across a seven-bit link. It does not prevent eight bit characters from being transmitted. The default is @samp{false}. It would be more common to specify this for a port than for a dialer. @item reliable @var{boolean} @findex reliable in dial file This is only used during protocol negotiation; if it is @samp{false}, it forces selection of a protocol which works across an unreliable communication link. The default is @samp{true}. @end table @node Security, , dial File, Configuration Files @section Security This discussion of UUCP security applies only to Unix. It is a bit cursory; suggestions for improvement are solicited. UUCP is traditionally not very secure. Taylor UUCP addresses some security issues, but is still far from being a secure system. If security is very important to you, then you should not permit any external access to your computer, including UUCP. Any opening to the outside world is a potential security risk. By default Taylor UUCP provides few mechanisms to secure local users of the system from each other. You can allow increased security by putting the owner of the UUCP programs (normally @code{uucp}) into a separate group; the use of this is explained in the following paragraphs, which refer to this separate group as @code{uucp-group}. When the @code{uucp} program is invoked to copy a file to a remote system, it will by default copy the file into the UUCP spool directory. When the @code{uux} program is used, the @samp{-C} switch must be used to copy the file into the UUCP spool directory. In any case, once the file has been copied into the spool directory, other local users will not be able to access it. In version 1.03 there is a security hole in that for the file to be copied it must be readable by @code{uucp}. Changing the group of the file to @code{uucp-group} and making it group readable will permit UUCP to read it without granting access to other users. When a file is requested from a remote system, UUCP will only permit it to be placed in a directory which is writable by the requesting user. The directory must also be writable by UUCP. A local user can create a directory with a group of @code{uucp-group} and set the mode to permit group write access. This will allow the file be requested without permitting it to be viewed by any other user. There is no provision for security for @code{uucp} requests (as opposed to @code{uux} requests) made by a user on a remote system. A file sent over by a remote request may only be placed in a directory which is world writable, and the file will be world readable and writable. This will permit any local user to destroy or replace the contents of the file. A file requested by a remote system must be world readable, and the directory it is in must be world readable. Any local user will be able to examine, although not necessarily modify, the file before it is sent. There are some security holes and race conditions that apply to the above discussion which I will not elaborate on. They are not hidden from anybody who reads the source code, but they are somewhat technical and difficult (but scarcely impossible) to exploit. Suffice it to say that even under the best of conditions UUCP is not completely secure. For many sites, security from remote sites is a more important consideration. Fortunately, Taylor UUCP does provide some support in this area. The greatest security is provided by always dialing out to the other site. This prevents anybody from pretending to be the other site. Of course, only one side of the connection can do this. If remote dialins must be permitted, then it is best if the dialin line is used only for UUCP. If this is the case, then you should create a call-in password file (@pxref{Configuration File Names}) and let @code{uucico} do its own login prompting. For example, to let remote sites log in on a port named @samp{entry} in the port file (@pxref{port file}) you might invoke @samp{uucico -p entry}. This would cause @code{uucico} to enter an endless loop of login prompts and daemon executions. The advantage of this approach is that even if remote users break into the system by guessing or learning the password, they will only be able to do whatever @code{uucico} permits them to do. They will not be able to start a shell on your system. If remote users can dial in and log on to your system, then you have a security hazard more serious than that posed by UUCP. But then, you probably knew that already. Once your system has connected with the remote UUCP, there is a fair amount of control you can exercise. You can use the @code{remote-send} and @code{remote-receive} commands to control the directories the remote UUCP can access. You can use the @code{request} command to prevent the remote UUCP from making any requests of your system at all; however, if you do this it will not even be able to send you mail or news. If you do permit remote requests, you should be careful to restrict what commands may be executed at the remote system's request. The default is @code{rmail} and @code{rnews}, which will suffice for most systems. If different remote systems call in and they must be granted different privileges (perhaps some systems are within the same organization and some are not) then the @code{called-login} command should be used for each system to require that they different login names. Otherwise it would be simple for a remote system to use the @code{myname} command and pretend to be a different system. The @code{sequence} command can be used to detect when one system pretended to be another, but since the sequence numbers must be reset manually after a failed handshake this can sometimes be more trouble than it's worth. @node Protocols, Hacking, Configuration Files, Top @chapter UUCP protocol internals This chapter describes how the various UUCP protocols work, and discusses some other internal UUCP issues. This chapter is quite technical. You do not need to understand it, or even read it, in order to use Taylor UUCP. It is intended for people who are interested in how UUCP code works. Most of the discussion covers the protocols used by all UUCP packages, not just Taylor UUCP. Any information specific to Taylor UUCP is indicated as such. There are some pointers to the actual functions in the Taylor UUCP source code, for those who are extremely interested in actual UUCP implementation. @menu * Grades:: UUCP grades * Lock Files:: UUCP lock file format * UUCP Protocol:: The common UUCP protocol * g Protocol:: The UUCP @samp{g} protocol * f Protocol:: The UUCP @samp{f} protocol * t Protocol:: The UUCP @samp{t} protocol * e Protocol:: The UUCP @samp{e} protocol * x Protocol:: The UUCP @samp{x} protocol * d Protocol:: The UUCP @samp{d} protocol * Capital G Protocol:: The UUCP @samp{G} protocol * Documentation References:: Documentation references @end menu @node Grades, Lock Files, Protocols, Protocols @section UUCP Grades @cindex grades Modern UUCP packages support grades for each command. The grades generally range from @samp{A} (the highest) to @samp{Z} followed by @samp{a} to @samp{z}. Taylor UUCP also supports @samp{0} to @samp{9} before @samp{A}. Some UUCP packages may permit any ASCII character as a grade. On Unix, these grades are encoded in the name of the command file. A command file name generally has the form @example C.nnnngssss @end example @noindent where @var{nnnn} is the remote system name for which the command is queued, @var{g} is a single character grade, and @var{ssss} is a four character sequence number. For example, a command file created for the system @file{airs} at grade @samp{Z} might be named @example C.airsZ2551 @end example The remote system name will be truncated to seven characters, to ensure that the command file name will fit in the 14 character file name limit of the traditional Unix file system. UUCP packages which have no other means of distinguishing which command files are intended for which systems thus require all @emph{systems they connect to} to have names that are unique in the first seven characters. Some UUCP packages use a variant of this format which truncates the system name to six characters. BNU uses a different spool directory format, which allows up to fourteen characters to be used for each system name. The Taylor UUCP spool directory format is configurable. The new Taylor spool directory format permits system names to be as long as file names; the maximum length of a file name depends on the particular Unix file system being used. The sequence number in the command file name may be a decimal integer, or it may be a hexadecimal integer, or it may contain any alphanumeric character. Different UUCP packages are different. Taylor UUCP creates command files in the function @code{zsysdep_spool_commands}. The file name is constructed by the function @code{zsfile_name}, which knows about all the different types of spool directories supported by Taylor UUCP. The Taylor UUCP sequence number can contain any alphanumeric character; the next sequence number is determined by the function @code{fscmd_seq}. I do not know how command grades are handled in non-Unix UUCP packages. Modern UUCP packages allow you to restrict file transfer by grade depending on the time of day. Typically this is done with a line in the @file{Systems} (or @file{L.sys}) file like this: @example airs Any/Z,Any2305-0855 ... @end example This allows only grades @samp{Z} and above to be transferred at any time. Lower grades may only be transferred at night. I believe that this grade restriction applies to local commands as well as to remote commands, but I am not sure. It may only apply if the UUCP package places the call, not if it is called by the remote system. Taylor UUCP can use the @code{timegrade} and @code{call-timegrade} commands (@pxref{When to Call}) to achieve the same effect (and supports the above format when reading @file{Systems} or @file{L.sys}). This sort of grade restriction is most useful if you know what grades are being used at the remote site. The default grades used depend on the UUCP package. Generally @code{uucp} and @code{uux} have different defaults. A particular grade can be specified with the @samp{-g} option to @code{uucp} or @code{uux}. For example, to request execution of rnews on airs with grade @samp{d}, you might use something like @example uux -gd - airs!rnews
= 128}, let @code{b2} be the second byte in the data field. Then there are @code{l - ((b1 & 0x7f) + (b2 << 7))} valid bytes of data in the data field, beginning with the third byte. In all cases @code{l} bytes of data are sent (and all data bytes participate in the checksum calculation) but some of the trailing bytes may be dropped by the receiver. The @var{xxx} and @var{yyy} fields are described below. @end table In a data packet (short or not) the @var{xxx} field gives the sequence number of the packet. Thus sequence numbers can range from 0 to 7, inclusive. The @var{yyy} field gives the sequence number of the last correctly received packet. Each communication direction uses a window which indicates how many unacknowledged packets may be transmitted before waiting for an acknowledgement. The window may range from 1 to 7 packets, and may be different in each direction. For example, if the window is 3 and the last packet acknowledged was packet number 6, packet numbers 7, 0 and 1 may be sent but the sender must wait for an acknowledgement before sending packet number 2. This acknowledgement could come as the @var{yyy} field of a data packet or as the @var{yyy} field of a @code{RJ} or @code{RR} control packet (described below). Each packet must be transmitted in order (the sender may not skip sequence numbers). Each packet must be acknowledged, and each packet must be acknowledged in order. In a control packet, the @var{xxx} field takes on the following values: @table @asis @item 1 @code{CLOSE} The connection should be closed immediately. This is typically sent when one side has seen too many errors and wants to give up. It is also sent when shutting down the protocol. If an unexpected @code{CLOSE} packet is received, a @code{CLOSE} packet should be sent in reply and the @samp{g} protocol should halt, causing UUCP to enter the final handshake. @item 2 @code{RJ} or @code{NAK} The last packet was not received correctly. The @var{yyy} field contains the sequence number of the last correctly received packet. @item 3 @code{SRJ} Selective reject. The @var{yyy} field contains the sequence number of a packet that was not received correctly, and should be retransmitted. This is not used by UUCP, and most implementations will not recognize it. Taylor UUCP will recognize it but not generate it. @item 4 @code{RR} or @code{ACK} Packet acknowledgement. The @var{yyy} field contains the sequence number of the last correctly received packet. @item 5 @code{INITC} Third initialization packet. The @var{yyy} field contains the maximum window size to use. @item 6 @code{INITB} @ifinfo Second initialization packet. The @var{yyy} field contains the packet size to use. It requests a size of 2 ** (@var{yyy} + 5). Note that this is not the same coding used for the @var{k} byte in the packet header (it is 1 less). Some UUCP implementations can handle any packet size up to that specified; some can only handled exactly the size specified. Taylor UUCP will always accept any packet size. @end ifinfo @iftex Second initialization packet. The @var{yyy} field contains the packet size to use. It requests a size of @math{2^{@var{yyy}+5}}. Note that this is not the same coding used for the @var{k} byte in the packet header (it is 1 less). Some UUCP implementations can handle any packet size up to that specified; some can only handled exactly the size specified. Taylor UUCP will always accept any packet size. @end iftex @item 7 @code{INITA} First initialization packet. The @var{yyy} field contains the maximum window size to use. @end table To compute the checksum, call the control byte (the fifth byte in the header) @code{c}. The checksum of a control packet is simply @code{0xaaaa - c}. The checksum of a data packet is @code{0xaaaa - (@var{check} ^ c)} (@code{^} denotes exclusive or, as in C), and @code{@var{check}} is the result of the following routine run on the contents of the data field (every byte in the data field participates in the checksum, even for a short data packet). Below is the routine used by Taylor UUCP; it is a slightly modified version of a routine which John Gilmore patched from G.L. Chesson's original paper. The @code{z} argument points to the data and the @code{c} argument indicates how much data there is. @example int igchecksum (z, c) register const char *z; register int c; @{ register unsigned int ichk1, ichk2; ichk1 = 0xffff; ichk2 = 0; do @{ register unsigned int b; /* Rotate ichk1 left. */ if ((ichk1 & 0x8000) == 0) ichk1 <<= 1; else @{ ichk1 <<= 1; ++ichk1; @} /* Add the next character to ichk1. */ b = *z++ & 0xff; ichk1 += b; /* Add ichk1 xor the character position in the buffer counting from the back to ichk2. */ ichk2 += ichk1 ^ c; /* If the character was zero, or adding it to ichk1 caused an overflow, xor ichk2 to ichk1. */ if (b == 0 || (ichk1 & 0xffff) < b) ichk1 ^= ichk2; @} while (--c > 0); return ichk1 & 0xffff; @} @end example When the @samp{g} protocol is started, the calling UUCP sends an INITA control packet with the window size it wishes the called UUCP to use. The called UUCP responds with an INITA packet with the window size it wishes the calling UUCP to use. Pairs of INITB and INITC packets are then similarly exchanged. When these exchanges are completed, the protocol is considered to have been started. The window size is sent twice, with both the INITA and the INITC packets. When a UUCP package transmits a command, it sends one or more data packets. All the data packets will normally be complete, although some UUCP packages may send the last one as a short packet. The command string is sent with a trailing null byte, to let the receiving package know when the command is finished. Some UUCP packages require the last byte of the last packet sent to be null, even if the command ends earlier in the packet. Some packages may require all the trailing bytes in the last packet to be null, but I have not confirmed this. When a UUCP package sends a file, it will send a sequence of data packets. The end of the file is signalled by a short data packet containing zero valid bytes (it will normally be preceeded by a short data packet containing the last few bytes in the file). Note that the sequence numbers cover the entire communication session, including both command and file data. When the protocol is shut down, each UUCP package sends a @code{CLOSE} control packet. @node f Protocol, t Protocol, g Protocol, Protocols @section The UUCP @samp{f} Protocol @cindex f protocol @cindex protocol (f) The @samp{f} protocol is a seven bit protocol which checksums an entire file at a time. It only uses the characters between \040 and \176 (ASCII space and @samp{~}) inclusive as well as the carriage return character. It can be very efficient for transferring text only data, but it is very inefficient at transferring eight bit data (such as compressed news). It is not flow controlled, and the checksum is fairly insecure over large files, so using it over a serial connection requires handshaking (@code{XON}/@code{XOFF} can be used) and error correcting modems. Some people think it should not be used even under those circumstances. I believe the @samp{f} protocol originated in BSD versions of UUCP. It was originally intended for transmission over X.25 PAD links. The Taylor UUCP code for the @samp{f} protocol is in @file{protf.c}. The @samp{f} protocol has no startup or finish protocol. However, both sides typically sleep for a couple of seconds before starting up, because they switch the terminal into @code{XON}/@code{XOFF} mode and want to allow the changes to settle before beginning transmission. When a UUCP package transmits a command, it simply sends a string terminated by a carriage return. When a UUCP package transmits a file, each byte b of the file is translated according to the following table: @example 0 <= b <= 037: 0172, b + 0100 (0100 to 0137) 040 <= b <= 0171: b ( 040 to 0171) 0172 <= b <= 0177: 0173, b - 0100 ( 072 to 077) 0200 <= b <= 0237: 0174, b - 0100 (0100 to 0137) 0240 <= b <= 0371: 0175, b - 0200 ( 040 to 0171) 0372 <= b <= 0377: 0176, b - 0300 ( 072 to 077) @end example That is, a byte between \040 and \171 inclusive is transmitted as is, and all other bytes are prefixed and modified as shown. When all the file data is sent, a seven byte sequence is sent: two bytes of \176 followed by four ASCII bytes of the checksum as printed in base 16 followed by a carriage return. For example, if the checksum was 0x1234, this would be sent: "\176\1761234\r". The checksum is initialized to 0xffff. For each byte that is sent it is modified as follows (where @code{b} is the byte before it has been transformed as described above): @example /* Rotate the checksum left. */ if ((ichk & 0x8000) == 0) ichk <<= 1; else @{ ichk <<= 1; ++ichk; @} /* Add the next byte into the checksum. */ ichk += b; @end example When the receiving UUCP sees the checksum, it compares it against its own calculated checksum and replies with a single character followed by a carriage return. @table @samp @item G The file was received correctly. @item R The checksum did not match, and the file should be resent from the beginning. @item Q The checksum did not match, but too many retries have occurred and the communication session should be abandoned. @end table The sending UUCP checks the returned character and acts accordingly. @node t Protocol, e Protocol, f Protocol, Protocols @section The UUCP @samp{t} Protocol @cindex t protocol @cindex protocol (t) The @samp{t} protocol is intended for TCP links. It does no error checking or flow control, and requires an eight bit clear channel. I believe the @samp{t} protocol originated in BSD versions of UUCP. The Taylor UUCP code for the @samp{t} protocol is in @file{prott.c}. When a UUCP package transmits a command, it first gets the length of the command string, @var{c}. It then sends ((@var{c} / 512) + 1) * 512 bytes (the smallest multiple of 512 which can hold @var{c} bytes plus a null byte) consisting of the command string itself followed by trailing null bytes. When a UUCP package sends a file, it sends it in blocks. Each block contains at most 1024 bytes of data. Each block consists of four bytes containing the amount of data in binary (most significant byte first, the same format as used by the Unix function @code{htonl}) followed by that amount of data. The end of the file is signalled by a block containing zero bytes of data. @node e Protocol, x Protocol, t Protocol, Protocols @section The UUCP @samp{e} Protocol @cindex e protocol @cindex protocol (e) The @samp{e} protocol is similar to the @samp{t} protocol. It does no flow control or error checking and is intended for use over TCP. The @samp{e} protocol originated in versions of BNU UUCP. The Taylor UUCP code for the @samp{e} protocol is in @file{prote.c}. When a UUCP package transmits a command, it simply sends the command as an ASCII string terminated by a null byte. When a UUCP package transmits a file, it sends the complete size of the file as an ASCII decimal number. The ASCII string is padded out to 20 bytes with null bytes (i.e., if the file is 1000 bytes long, it sends @samp{1000\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0}). It then sends the entire file. @node x Protocol, d Protocol, e Protocol, Protocols @section The UUCP @samp{x} Protocol I believe that the @samp{x} protocol was intended for use over X.25 virtual circuits. It relies on a write of zero bytes being read as zero bytes without stopping communication. I have heard that it does not work correctly. If someone would care to fill this in more, I would be grateful. Taylor UUCP does not implement the @samp{x} protocol. @node d Protocol, Capital G Protocol, x Protocol, Protocols @section The UUCP @samp{d} Protocol This is apparently used for DataKit connections, and relies on a write of zero bytes being read as zero bytes, much as the @samp{x} protocol does. I don't really know anything else about it. Taylor UUCP does not implement the @samp{d} protocol. @node Capital G Protocol, Documentation References, d Protocol, Protocols @section The UUCP @samp{G} Protocol The @samp{G} protocol is apparently simply the @samp{g} protocol, except that it is known to support all possible window and packet sizes. It was introduced by SVR4 UUCP; the SVR4 implementation of the @samp{g} protocol is apparently fixed at a packet size of 64 and a window size of 7. Taylor UUCP does not recognize the @samp{G} protocol. It does support all window and packet sizes for the @samp{g} protocol. @node Documentation References, , Capital G Protocol, Protocols @section Documentation References I took a lot of the information from Jamie E. Hanrahan's paper in the Fall 1990 DECUS Symposium, and from Managing UUCP and Usenet by Tim O'Reilly and Grace Todino (with contributions by several other people). The latter includes most of the former, and is published by O'Reilly & Associates, Inc. Some information is originally due to a Usenet article by Chuck Wegrzyn. The information on the @samp{g} protocol comes partially from a paper by G.L. Chesson of Bell Laboratories, partially from Jamie E. Hanrahan's paper, and partially from source code by John Gilmore. The information on the @samp{f} protocol comes from the source code by Piet Berteema. The information on the @samp{t} protocol comes from the source code by Rick Adams. The information on the @samp{e} protocol comes from a Usenet article by Matthias Urlichs. @node Hacking, Acknowledgements, Protocols, Top @chapter Hacking Taylor UUCP This chapter provides the briefest of guides to the Taylor UUCP source code itself. @menu * System Dependence:: System Dependence * Naming Conventions:: Naming Conventions * Patches:: Patches @end menu @node System Dependence, Naming Conventions, Hacking, Hacking @section System Dependence The code is carefully segregated into a system independent portion and a system dependent portion. The system dependent code is in @file{sys?.*} and @file{tcp.c}. Note that @file{sysh.*} is included as @file{sysdep.h}. Currently the only system dependent files are for Unix, and the file name for all of them ends in @file{.unx}. Hopefully the code will eventually be ported to other systems. With the right configuration parameters, the system independent code calls only ANSI C functions. Some of the less common ANSI C functions are also provided in @file{util.c}. The replacement function @code{strtol} in @file{util.c} assumes that the characters @kbd{A} to @kbd{F} and @kbd{a} to @kbd{f} appear in strictly sequential order. The function @code{igradecmp} in @file{config.c} assumes that the upper and lower case letters appear in order. Both assumptions are true for ASCII and EBCDIC, but neither is guaranteed by ANSI C. The replacement function @code{memmove} in @file{util.c} assumes that two arbitrary pointers may be safely compared. Disregarding these caveats, I believe that the system independent portion of the code is strictly conforming. That's not too exciting, since all the work is done in the system dependent code. I think that this code can conform to POSIX 1003.1, given the right compilation parameters. I'm a bit less certain about this, though. The code is in use on a 16 bit segmented system with no function prototypes, so I'm certain that all casts to long and pointers are done when necessary. The code uses alloca extensively. It comes with a simple replacement, in @file{alloca.c} (otherwise I would lost ANSI C conformance, after all). Using a real @code{alloca} function will be considerably more efficient. It will also cause significant stack usage, which may be a problem on systems without virtual memory. @node Naming Conventions, Patches, System Dependence, Hacking @section Naming Conventions I use a modified Hungarian naming convention for my variables and functions. As with all naming conventions, the code is rather opaque if you are not familiar with it, but becomes clear and easy to use with time. The first character indicates the type of the variable (or function return value). Sometimes additional characters are used. I use the following type prefixes: @table @samp @item a array; the next character is the type of an element @item b byte or character @item c count of something @item e stdio FILE * @item f boolean @item i generic integer @item l double @item o file descriptor (as returned by open, creat, etc.) @item p generic pointer @item q pointer to structure @item s structure @item u void (function return values only) @item z character string @end table A generic pointer ('p') is sometimes a @code{void *}, sometimes a function pointer in which case the prefix is pf, and sometimes a pointer to another type, in which case the next character is the type to which it points (pf is overloaded). An array of strings (@code{char *[]}) would be named @code{az} (array of string). If this array were passed to a function, the function parameter would be named @code{paz} (pointer to array of string). Note that the variable name prefixes do not necessarily indicate the type of the variable. For example, a variable prefixed with i may be int, long or short. Similarly, a variable prefixed with b may be a char or an int; for example, the return value of getchar would be caught in an int variable prefixed with b. For a non-local variable (extern or file static), the first character after the type prefix is capitalized. Most static variables and functions use another letter after the type prefix to indicate which module they come from. This is to help distinguish different names in the debugger. For example, all static functions in @file{protg.c}, the @samp{g} protocol source code, use a module prefix of @samp{g}. This isn't too useful, as a number of modules use a module prefix of @samp{s}. @node Patches, , Naming Conventions, Hacking @section Patches I am always grateful for any patches sent in. Much of the flexibility and portability of the code is due to other people. Please do not hesitate to send me any changes you have found necessary or useful. I rarely apply the patches directly. Instead I work my way through them and apply each one separately. This ensures that the naming remains consistent and that I understand all the code. @node Acknowledgements, Index (concepts), Hacking, Top @chapter Acknowledgements This is a list of people who gave help or suggestions while I was working on the Taylor UUCP project. Appearance on this list does not constitute endorsement of the program, particularly since some of the comments were criticisms. I've probably left some people off, and I apologize for any oversight; it does not mean your contribution was unappreciated. @ifinfo First of all, I would like to thank the people at Infinity Development Systems (formerly AIRS, which lives on in the domain name, at least for now) for permitting me to use their computers and @file{uunet} access. I would also like to thank Richard Stallman @file{} for founding the Free Software Foundation and John Gilmore @file{} for writing the initial version of gnuucp which was a direct inspiration for this somewhat larger project. Chip Salzenberg @file{} contributed many early patches. Franc,ois Pinard @file{} tirelessly tested the code and suggested many improvements. He also put together the initial version of this document. Finally, Verbus M. Counts @file{} and Centel Federal Systems, Inc. deserve special thanks, since they actually paid me money to port this code to System III. @end ifinfo @iftex First of all, I would like to thank the people at Infinity Development Systems (formerly AIRS, which lives on in the domain name, at least for now) for permitting me to use their computers and @file{uunet} access. I would also like to thank Richard Stallman @file{} for founding the Free Software Foundation and John Gilmore @file{} for writing the initial version of gnuucp which was a direct inspiration for this somewhat larger project. Chip Salzenberg @file{} contributed many early patches. @tex Fran\c cois Pinard @end tex @file{} tirelessly tested the code and suggested many improvements. He also put together the initial version of this document. Finally, Verbus M. Counts @file{} and Centel Federal Systems, Inc. deserve special thanks, since they actually paid me money to port this code to System III. @end iftex In alphabetical order: @example "Earle F. Ake - SAIC" @file{} @file{mra@@searchtech.com} (Michael Almond) @file{cambler@@zeus.calpoly.edu} (Christopher J. Ambler) Brian W. Antoine @file{} @file{jantypas@@soft21.s21.com} (John Antypas) @file{nba@@sysware.DK} (Niels Baggesen) @file{uunet!hotmomma!sdb} (Scott Ballantyne) @file{magus!dolphin!zack} (Zacharias Beckman) @file{mike@@mbsun.ann-arbor.mi.us} (Mike Bernson) @file{bob@@usixth.sublink.org} (Roberto Biancardi) Marc Boucher @file{} @file{dean@@coplex.com} (Dean Brooks) @file{dave@@dlb.com} (Dave Buck) @file{gordon@@sneaky.lonestar.org} (Gordon Burditt) @file{mib@@gnu.ai.mit.edu} (Michael I Bushnell) Brian Campbell @file{} @file{verbus@@westmark.westmark.com} (Verbus M. Counts) @file{cbmvax!snark.thyrsus.com!cowan} (John Cowan) @file{denny@@dakota.alisa.com} (Bob Denny) @file{dje@@ersys.edmonton.ab.ca} (Doug Evans) @file{fenner@@jazz.psu.edu} (Bill Fenner) "David J. Fiander" @file{} Thomas Fischer @file{} @file{erik@@eab.retix.com} (Erik Forsberg) Lele Gaifax @file{} @file{Peter.Galbavy@@micromuse.co.uk} @file{hunter@@phoenix.pub.uu.oz.au} (James Gardiner [hunter]) Terry Gardner @file{} @file{jimmy@@tokyo07.info.com} (Jim Gottlieb) @file{ryan@@cs.umb.edu} (Daniel R. Guilderson) @file{greg@@gagme.chi.il.us} (Gregory Gulik) Michael Haberler @file{} @file{guy@@auspex.auspex.com} (Guy Harris) Petri Helenius @file{} Peter Honeyman @file{} @file{bei@@dogface.austin.tx.us} (Bob Izenberg) @file{harvee!esj} (Eric S Johansson) @file{chris@@cj_net.in-berlin.de} (Christof Junge) @file{tron@@Veritas.COM} (Ronald S. Karr) @file{kent@@sparky.IMD.Sterling.COM} (Kent Landfield) @file{lebaron@@inrs-telecom.uquebec.ca} (Gregory LeBaron) @file{karl@@sugar.NeoSoft.Com} (Karl Lehenbauer) @file{libove@@libove.det.dec.com} (Jay Vassos-Libove) @file{bruce%blilly@@Broadcast.Sony.COM} (Bruce Lilly) Ted Lindgreen @file{} "Arne Ludwig" @file{} Matthew Lyle @file{} @file{djm@@eng.umd.edu} (David J. MacKenzie) John R MacMillan @file{} @file{mem@@mv.MV.COM} (Mark E. Mallett) @file{martelli@@cadlab.sublink.org} (Alex Martelli) Yanek Martinson @file{} @file{les@@chinet.chi.il.us} (Leslie Mikesell) @file{mmitchel@@digi.lonestar.org} (Mitch Mitchell) @file{rmohr@@infoac.rmi.de} (Rupert Mohr) @file{service@@infohh.rmi.de} (Dirk Musstopf) @file{lyndon@@cs.athabascau.ca} (Lyndon Nerenberg) @file{nolan@@helios.unl.edu} (Michael Nolan) david nugent @file{} @file{abekas!dragoman!mikep@@decwrl.dec.com} (Mike Park) "Mark Pizzolato 415-369-9366" @file{} @file{dplatt@@ntg.com} (Dave Platt) @file{eldorado@@tharr.UUCP} (Mark Powell) @file{pozar@@kumr.lns.com} (Tim Pozar) @file{putsch@@uicc.com} (Jeff Putsch) Jarmo Raiha @file{} @file{mcr@@Sandelman.OCUnix.On.Ca} (Michael Richardson) @file{ross@@sun490.fdu.edu} (Jeff Ross) Aleksey P. Rudnev @file{} @file{wolfgang@@wsrcc.com} (Wolfgang S. Rupprecht) @file{tbr@@tfic.bc.ca} (Tom Rushworth) @file{rsalz@@bbn.com} (Rich Salz) @file{sojurn!mike@@hobbes.cert.sei.cmu.edu} (Mike Sangrey) @file{swiers@@plains.NoDak.edu} @file{s4mjs!mjs@@nirvo.nirvonics.com} (M. J. Shannon Jr.) @file{peter@@ficc.ferranti.com} (Peter da Silva) @file{frumious!pat} (Patrick Smith) @file{roscom!monty@@bu.edu} (Monty Solomon) @file{chs@@antic.apu.fi} (Hannu Strang) @file{ralf@@reswi.ruhr.de} (Ralf E. Stranzenbach) Oleg Tabarovsky @file{} John Theus @file{} @file{rmtodd@@servalan.servalan.com} (Richard Todd) Len Tower @file{} @file{mju@@mudos.ann-arbor.mi.us} (Marc Unangst) @file{jv@@mh.nl} (Johan Vromans) @file{rna-nl!gerben@@relay.nluug.nl} (Drs. Gerben C. Th. Wierda) @file{frnkmth!twwells.com!bill} (T. William Wells) @file{mauxci!eci386!woods@@apple.com} (Greg A. Woods) @file{jon@@console.ais.org} (Jon Zeeff) Eric Ziegast @file{} @end example @node Index (concepts), Index (configuration file), Acknowledgements, Top @unnumbered Concept Index @printindex cp @node Index (configuration file), , Index (concepts), Top @unnumbered Index to New Configuration File @printindex fn @contents @bye