diff --git a/README.md b/README.md new file mode 100644 index 0000000..142c133 --- /dev/null +++ b/README.md @@ -0,0 +1,373 @@ +Readme.txt for IFS v1.1: + +1. Introduction and Overview +============================ + +In the 1970s, Xerox PARC developed a set of protocols based around the "PUP" +(the "PARC Universal Packet"). These were intended to be a stopgap until +something "real" could be designed and implemented, so the suite was referred +to as "IFS" ("Interim File Server"). That "real" implementation never came +into being during the Alto's lifetime, so the IFS was a permanent fixture of +the network environment at PARC during the heyday of the Alto. + +The LCM+L's IFS implementation is an implementation of this protocol suite +that runs on a modern PC, and is designed to work with the ContrAlto Alto +emulator over either Raw Ethernet packets or UDP broadcasts. + +It provides the following IFS services: + + - BreathOfLife: Provides the "Breath Of Life" packet needed to bootstrap + an Alto over the network. + - EFTP/Boot: Provides boot files over the network. + - FTP: File Transfer Protocol. + - CopyDisk: Allows imaging and restoring of Alto disk packs over the + network. + - Misc. Services: Provides network name lookup, time and other miscellaneous + services. + - Mail: Delivers mail to other users. + + +The following services are not yet provided, but are planned: + + - EFTP/Printing: Provides print services to networked Altos + - Gateway: Routes PUPs to other Alto networks across the Internet + +If you have questions, or run into issues or have feature requests, please +feel free to e-mail me at joshd@livingcomputers.org. + + +1.1 Getting Started +------------------- + +IFS does not provide an installer; unzip the archive to a directory on the +machine you wish to use as a server. Modify the configuration files in the +"Conf" directory to your liking (See Section 2.0) and run the "IFS.exe" +executable to run the IFS services. The startup banner will print and you'll +be at the Console command prompt (See Section 3.0 for details). The IFS +server is now running and is ready to serve your network of Altos. + + +1.2 Important Note +------------------ + +This IFS implementation is still a work in progress and should not be used for +any mission-critical or security-critical purposes. IFS protocols sent +passwords in plain-text and in general were not designed with tight security +in mind. All files (even those in user directories) are globally readable. + + +2.0 Configuration +================= + +IFS uses a set of files in the "Conf" subdirectory to configure the server. +These include: + + - accounts.txt: Defines the set of user accounts + - bootdirectory.txt: Maps boot numbers to boot files for network boot + - hosts.txt: Maps Inter-network numbers to names + - ifs.cfg: General configuration for the IFS server + +2.1 ifs.cfg: +------------ + +ifs.cfg contains general configuration details for the server. It specifies +configuration for the network transport, directory paths and debugging options. + +Directory configuration: + - FTPRoot: Specifies the path for the root of the FTP directory tree. + - CopyDiskRoot: Specifies the path for the directory to store CopyDisk + images. + - BootRoot: Specifies the path for boot images. + - MailRoot: Specifies the path for the root of the Mail directory tree. + (User mail folders are placed in this directory.) + +Interface configuration: + - InterfaceType: "RAW" or "UDP". Specifies the transport to use for + communication. + - InterfaceName: The name of the host network adapter to use for + communication. + + - UDPPort: The port number (decimal) to use for the UDP transport. + +Network configuration: + - ServerNetwork: The IFS server's network number. + - ServerHost: The IFS server's host number. + +Debugging configuration: + - LogTypes: The level of verbosity for logging. One of: + None, Normal, Warning, Error, Verbose, or All + + - LogComponent: The components to log details about. One of: + None, Ethernet, RTP, BSP, MiscServices, CopyDisk, + DirectoryServices, PUP, FTP, BreathOfLife, EFTP, + BootServer, UDP, Mail, Configuration, or All + +2.2 hosts.txt: +-------------- + +hosts.txt maps Xerox "inter-network" names to hostnames. If you're familiar +with /etc/hosts on UNIX-like machines, this will be very familiar. + +Each line is either a comment (beginning with '#') or contains an inter-network +name and a hostname to associate with it, separated by whitespace. At this +time, each inter-network name maps to exactly one hostname. + +A Xerox "inter-network name" defines a host number and a network number, and is +expressed in the format "##", where both and +are octal values between 0 and 377. So, for example, an Alto on network 5 +with host number 72 would have an inter-network name of "5#72#". Hosts on the +same network as the IFS server (see Section 2.1 for IFS server configuration) +need not specify the network number and have the format of "#". + +A Hostname is an alphanumeric sequence that must begin with a letter. + +A hosts.txt entry for our Alto on network 5 with host number 72 providing said +system with name "alan" would thus look like: + +5#72# alan + +Or optionally, if our IFS server is on network 5: + +72# alan + +It is a good idea to provide an entry for the IFS server itself so that the +server can easily be reached by name. By default (unless ifs.cfg has been +changed), the IFS server's inter-network name is 1#1# (network 1, host 1). + + +2.3 bootdirectory.txt +--------------------- + +bootdirectory.txt maps boot numbers to the bootfile they correspond to. The +file format is very similar to the hosts.txt file -- each line consists of +either a comment (again beginning with '#') or contains a boot file number (in +octal) and the boot file to associate with it. + +The boot files listed in bootdirectory.txt correspond to files placed in the +BootRoot directory, as specified in ifs.cfg (see Section 2.1 for details). + +By default bootdirectory.txt contains a set of entries that map to the file +numbers conventionally used at Xerox PARC. This allows Alto programs and +subsystems that rely on this convention to work properly. It is advisable +to leave these as is for this reason. Anything past 100 (octal) is fair game +generally, configure those as you will. + +Note that the IFS server does not include the actual boot files -- see Section +6.0 for details on where to find these files to populate your BootRoot +directory. + +2.4 accounts.txt +---------------- + +accounts.txt defines user accounts for the IFS system. + +Note: These accounts are unrelated to any user accounts that might be provided +by the host system (i.e.a Windows or Linux box that is running IFS). It is +*extremely* advisable to avoid using the same password for your IFS account +that you do for any real-world account (see Section 1.2). + +Each line in accounts.txt consists of either a comment (beginning with '#') +or a user definition. If you're familiar with /etc/password on UNIX systems +this will look very familiar. + +This file can be hand-edited using a text editor, but the file will be +re-generated if the Console (see Section 3.0) is used to add or modify user +accounts, so comments will be lost. It is generally advisable to use the +console to add, remove, or change user accounts. + +Each user definition is a line in the format: +:::: + + - username: an alphanumeric sequence starting with a letter. This + define's the user's login name. + - password hash: an encoded version of the user's password. This can be + edited, but is generally not advisable. See Section + 3.0 for details on setting and changing user passwords. + - privileges: Either Admin (administrative privileges) or User (normal + user privileges). See section 4.0 for details. + - full user name: Self explanatory; the full name (i.e. Alan Kay) of the + user. + - home directory: The user's directory (which is placed under the FTPRoot + directory). See Section 4.0 for details on user + directories. + +Changes made to this file while IFS is running will not take effect until IFS +is restarted. (This is another reason to use the Console to make changes -- +see Section 3.0). + +3.0 The Command Console +======================= + +The IFS server provides a command console, designated by the ">" prompt. The +console provides numerous commands for managing the state of the server and +for managing user accounts. + +The console provides simple command completion; hit the "TAB" key at any time +to see possible completions for the command you are entering. + +The "show commmands" command displays a list of possible commands with brief +synopses and descriptions. + +Here is a rundown of the basic command set: + + show users - Displays the current user database (See Section 4.0) + + show user - Displays information for the specified user + (See Section 4.0) + + set password - Sets the password for the specified user + (See Section 4.0) + + add user [User|Admin] + - Adds a new user account (See section 4.0 for details) + + remove user - Removes an existing user account (See Section 4.0) + + show active servers - Displays active server statistics. + + quit - Terminates the IFS process + + show commands - Shows console commands and their descriptions. + + +4.0 User Accounts, Authentication, and Security +=============================================== + +IFS provides a very simple model for user accounts, authentication and security. +It is by no means expected to be extensive or useful for all applications, nor +does it guarantee any level of security. It provides a set of facilities for +creating user accounts and assigning passwords and coarsely-grained permissions, +approximating the environment as it would have existed at Xerox PARC. + +Rephrasing the note in Section 1.2: Do not rely on IFS for security or privacy. +Allow only trusted users into the network that hosts IFS, and use common sense. + +4.1 User Accounts +----------------- + +Each user account is defined by an entry in the accounts.txt file (as described +in section 2.4). + +A new user account can be created either be editing the accounts.txt file, or +through use of the "add user" Console command. The latter is recommended. + +Each user can be assigned a password, or have his/her password changed using +the "set password" command. + +Every user gets his or her own user directory for files; this is a +subdirectory of the FTPRoot directory and will be automatically created by the +"add user" Console command (See Setion 3.0) and removed by the "remove user" +command. + +There are exactly two levels of privilege possible: User and Admin. A user +with "User" level privileges has read/write access to their own user file +directory, and read-only access to all other file directories (including other user +directories). A user with "Admin" privileges has read-write access to all +directories. + +Every user gets his or her own mail directory as a subdirectory +of the MailRoot directory. This directory is automatically created the first +time a user sends or receives mail. A given user's mail directory is only +readable (or writable) by that user, regardless of privilege. + +Additionally, every user (including guest) has read access to disk images in +the CopyDiskRoot directory. Administrative users also have the ability to +write new images to this directory. + + +4.2 The Guest Account +--------------------- + +There is one special account, the "guest" account. The guest account does not +have an entry in the accounts.txt file, and has no password. The guest user +has read-only access, but has no user directory. + +5.0 Network Transports: Care and Feeding +======================================== + +IFS simulates the original "Experimental" 3mbit Xerox Ethernet by encapsulating +3mbit packets in a modern transport, either via UDP broadcasts or via Raw +Ethernet packets. + +The transport type is configured in the ifs.cfg file (See Section 2.1) via the +"InterfaceType" parameter. The UDP port can be defined by the "UDPPort" parameter, +if unspecified it defaults to 42424. + +In both cases, packets are broadcast over the network. This is done in order +to make the use of the simulated network easier and to keep the implementation +simple as well. In general, Altos (simulated or otherwise) do not generate +large amounts of traffic as compared with the bandwidth of a modern network. +(The maximum throughput of an Alto transferring a file via FTP, for example, +is on the order of 20K/sec). It may be a good idea to run your IFS server +and Altos on a separate network segment if you are concerned about network +usage. + +You cannot run both the IFS server and a ContrAlto emulator on the same machine +if they are configured to use UDP as the transport. + +6.0 Where to Find Alto Files +============================ + +The IFS server distribution does not include any Alto files, but they can be +found in many places on the Internet. + +Disk images (for use with the CopyDisk protocol) and some boot files can be +found on Bitsavers, at http://bitsavers.org/bits/Xerox/Alto/. + +A wide variety of files, including programs, documentation, and related data +can be found in the CHM's Xerox PARC Alto filesystem archive at +http://xeroxalto.computerhistory.org/. The raw files can be downloaded and +placed in your FTPRoot or BootRoot directories as desired. + + +7.0 Xerox Documentation Reference +================================= + +The following documents may be useful in actually using the Alto-land client +tools (FTP, CopyDisk, mail, etc) to communicate with the IFS server: + +The Alto User's Handbook: + http://bitsavers.org/pdf/xerox/alto/Alto_Users_Handbook_Sep79.pdf +Alto Subsystems: + http://bitsavers.org/pdf/xerox/alto/memos_1981/Alto_Subsystems_May81.pdf + + +The following specifications were used to implement the IFS protocol suite: + +FTP: http://xeroxalto.computerhistory.org/_cd8_/pup/.ftpspec.press!2.pdf +Boot: http://xeroxalto.computerhistory.org/_cd8_/pup/.altoboot.press!1.pdf +CopyDisk: http://xeroxalto.computerhistory.org/_cd8_/pup/.copydisk.press!1.pdf +Gateway: +http://xeroxalto.computerhistory.org/_cd8_/pup/.gatewayinformation.press!1.pdf +Misc Services: +http://xeroxalto.computerhistory.org/_cd8_/pup/.miscservices.press!1.pdf + + +8.0 Packet-Level Protocol +========================= + +IFS (and ContrAlto) use a very simple encapsulation for transmitting 3mbit +Ethernet packets over modern transports. An encapsulated packet consists of +two fields: + - Packet Length (2 bytes): Length (in 16-bit words) of the 3mbit Packet + Data field (see below) + - Packet Data (N bytes): The 3mbit packet, including 3mbit Ethernet header + but excluding the checksum word. + +All words are stored in big-endian format. + +The Packet Length field is necessary to allow proper transport over Raw +Ethernet packets -- modern Ethernet defines a minimum length for a packet +whereas the Experimental 3mbit Ethernet (as implemented on the Alto) does not. +Short packets are therefore padded by the modern transport, so a separate field +is necessary in order to ascertain the intended packet length. + +As discussed in Section 5.0, all packets are broadcast. The technical reasons +for this are documented in the source code; see Transport\UDP.cs for details. + + +9.0 Thanks +========== + +This project would not have been possible without the conservation efforts of +the CHM and Bitsavers. diff --git a/license.txt b/license.txt new file mode 100644 index 0000000..dbbe355 --- /dev/null +++ b/license.txt @@ -0,0 +1,661 @@ + GNU AFFERO GENERAL PUBLIC LICENSE + Version 3, 19 November 2007 + + Copyright (C) 2007 Free Software Foundation, Inc. + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + Preamble + + The GNU Affero General Public License is a free, copyleft license for +software and other kinds of works, specifically designed to ensure +cooperation with the community in the case of network server software. + + The licenses for most software and other practical works are designed +to take away your freedom to share and change the works. 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No Surrender of Others' Freedom. + + If conditions are imposed on you (whether by court order, agreement or +otherwise) that contradict the conditions of this License, they do not +excuse you from the conditions of this License. If you cannot convey a +covered work so as to satisfy simultaneously your obligations under this +License and any other pertinent obligations, then as a consequence you may +not convey it at all. For example, if you agree to terms that obligate you +to collect a royalty for further conveying from those to whom you convey +the Program, the only way you could satisfy both those terms and this +License would be to refrain entirely from conveying the Program. + + 13. Remote Network Interaction; Use with the GNU General Public License. + + Notwithstanding any other provision of this License, if you modify the +Program, your modified version must prominently offer all users +interacting with it remotely through a computer network (if your version +supports such interaction) an opportunity to receive the Corresponding +Source of your version by providing access to the Corresponding Source +from a network server at no charge, through some standard or customary +means of facilitating copying of software. This Corresponding Source +shall include the Corresponding Source for any work covered by version 3 +of the GNU General Public License that is incorporated pursuant to the +following paragraph. + + Notwithstanding any other provision of this License, you have +permission to link or combine any covered work with a work licensed +under version 3 of the GNU General Public License into a single +combined work, and to convey the resulting work. The terms of this +License will continue to apply to the part which is the covered work, +but the work with which it is combined will remain governed by version +3 of the GNU General Public License. + + 14. Revised Versions of this License. + + The Free Software Foundation may publish revised and/or new versions of +the GNU Affero General Public License from time to time. Such new versions +will be similar in spirit to the present version, but may differ in detail to +address new problems or concerns. + + Each version is given a distinguishing version number. If the +Program specifies that a certain numbered version of the GNU Affero General +Public License "or any later version" applies to it, you have the +option of following the terms and conditions either of that numbered +version or of any later version published by the Free Software +Foundation. If the Program does not specify a version number of the +GNU Affero General Public License, you may choose any version ever published +by the Free Software Foundation. + + If the Program specifies that a proxy can decide which future +versions of the GNU Affero General Public License can be used, that proxy's +public statement of acceptance of a version permanently authorizes you +to choose that version for the Program. + + Later license versions may give you additional or different +permissions. However, no additional obligations are imposed on any +author or copyright holder as a result of your choosing to follow a +later version. + + 15. Disclaimer of Warranty. + + THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY +APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT +HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY +OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, +THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR +PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM +IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF +ALL NECESSARY SERVICING, REPAIR OR CORRECTION. + + 16. Limitation of Liability. + + IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING +WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS +THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY +GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE +USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF +DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD +PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), +EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF +SUCH DAMAGES. + + 17. Interpretation of Sections 15 and 16. + + If the disclaimer of warranty and limitation of liability provided +above cannot be given local legal effect according to their terms, +reviewing courts shall apply local law that most closely approximates +an absolute waiver of all civil liability in connection with the +Program, unless a warranty or assumption of liability accompanies a +copy of the Program in return for a fee. + + END OF TERMS AND CONDITIONS + + How to Apply These Terms to Your New Programs + + If you develop a new program, and you want it to be of the greatest +possible use to the public, the best way to achieve this is to make it +free software which everyone can redistribute and change under these terms. + + To do so, attach the following notices to the program. It is safest +to attach them to the start of each source file to most effectively +state the exclusion of warranty; and each file should have at least +the "copyright" line and a pointer to where the full notice is found. + + + Copyright (C) + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU Affero General Public License as published + by the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU Affero General Public License for more details. + + You should have received a copy of the GNU Affero General Public License + along with this program. If not, see . + +Also add information on how to contact you by electronic and paper mail. + + If your software can interact with users remotely through a computer +network, you should also make sure that it provides a way for users to +get its source. For example, if your program is a web application, its +interface could display a "Source" link that leads users to an archive +of the code. There are many ways you could offer source, and different +solutions will be better for different programs; see section 13 for the +specific requirements. + + You should also get your employer (if you work as a programmer) or school, +if any, to sign a "copyright disclaimer" for the program, if necessary. +For more information on this, and how to apply and follow the GNU AGPL, see +.