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Text File | 1995-02-27 | 24KB | 499 lines

======================================================================= This version of HPACK is a beta release of the final version. A previous version, version 0.75 was released as a prototype to get feedback from users for the final version. The 0.75 release carried a warning message that it was a prototype only and not for general use. The 0.78 release supersedes version 0.75, and includes: - Improved portability to all OS's (the Mac port was done in a *single day*), and easier portability to different mutations of Unix. - Public-key and conventional encryption of archives or individual files, legally usable both inside and outside the US. - Data authentication/manipulation detection using RSA digital signatures, legally usable both inside and outside the US. - Multi-disk archive handling (your mileage may vary on this). - Improved support for OS-specific features such as OS/2 extended attributes. - Various small improvements based on suggestions from users. - Improved support for multilingual versions (extended ASCII, Japanese DBCS, Unicode, etc). Currently HPACK is available in eight different languages and eleven different character sets. - High-quality Postscript documentation. Note: HPACK is a 100% matter product. In the unlikely event that it should contact antimatter in any form, a catastrophic explosion will result. ======================================================================= General Layout ============== The executable distribution of HPACK generally contains the following files: readme.1st - This file. hpack{.exe} - The HPACK archiver hpack.sig - Digital signature for executable (Arc, MSDOS, OS/2 only) language.dat - Internationalization information needed by HPACK language.sig - Digital signature for i18n info (Arc, MSDOS, OS/2 only) hpack.doc - The HPACK documentation. hpackext.doc - The extended documentation for advanced users. register.doc - HPACK registration form. key.asc - My PGP 2.0 public key (MSDOS, OS/2 only) keycvt{.exe} - HPACK keyring converter Some of these files may have slightly different names on different systems. The layout of the source distribution is given in the file HPACKSTD.TXT. Running HPACK: MSDOS and OS/2 ============================= The OS/2 version is quite similar to the DOS version, except that it is HPFS-aware and will handle extended attributes for files and directories if this is specified by the [-a]ttribute switch. This version will also give an HPACK archive certain extended attributes such as type and icon information. Apart from that, it behaves as the DOS version. The archive containing HPACK in fact contains two executables, HPACK_16.EXE and HPACK_32.EXE. HPACK_16.EXE is a 16-bit version for use with OS/2 versions before 2.0, and HPACK_32.EXE is a 32-bit version for use with OS/2 versions 2.0 and above. The appropriate executable should be renamed to HPACK.EXE before use. Bug alert: It has been reported that, in the MSDOS version when using unit compression and adding a large number (around 2000) of small files, HPACK would crash after processing around 1000 files. Unfortunately replication of this problem has so far proven impossible. If anyone plans to create a unit- compressed archive containing thousands of files, be warned that there may be a problem. Running HPACK: Unix =================== The Unix version of HPACK is distributed in source form as hpack78src.tar.Z. It has been tested under AIX (RS6000), AIX 386, AIX 370, BSD 386, Amdahl UTS4, Convex, Irix, ISC Unix, Linux, MiNT, NeXT, OSF/1, Posix, SunOs, SVR4, and Ultrix and is known to compile succesfully on these systems (Note that in some cases the code run wasn't the latest, up-to-the-minute release so it may be necessary to tweak a line or two). Hopefully it should be possible to compile it on other systems with a minimum amount of modification. Before compiling it on a new system, you'll probably need to edit the makefile for your system (Unix flavour), and depending on your Unix flavour you will probably have to tune system.h and system/unix.c a bit (eg if you've got a memmove() or not, a rename(), and a few other odds and ends). It took about half an hour for Ultrix (of which about 20 minutes was spent waiting for the compiler), in general it only seems to take a few minutes to adapt it to any new Unix variant. In addition, you'll have to set tabstops to 4 in whatever editor you're using. Virtually all the editors used on various systems for HPACK have tabs set to 4, but most Unix editors default to 8. The only problems you may run into is with running it on 64-bit systems, I don't have any experience with them so maybe I'm just being pessimistic, certainly the move from 16 to 32-bit showed up only one minor problem which was fixed in about 5 minutes. Once you get it going, send the diffs to me (pgut1@cs.aukuni.ac.nz) and I'll integrate them into the code. If you can't get it to compile on one of the above systems, I can probably arrange to mail you an executable - hassle me via email. Running HPACK: Mac ================== The Mac version is currently a rather simplistic port of the generic CLI code. When run, it will prompt for a command-line as used by the CLI version, and display all output on the console window. A full Mac implementation should eventually become available, based on the Windows version. To compile HPACK for the Mac, use the BinHex'd project and resource files in the system subdirectory. The Mac port was done in a single day, mainly to demonstrate how easy it was to move it to virtually any OS, even one whose filesystem interface is radically different from the generic Unix-like one assumed by the high-level code. The fact that it was done in one day shows when the program is run, if anyone wants to add the usual GUI paraphernalia let me know. THIS IS NOT THE FINAL FORM OF THE MACINTOSH VERSION OF HPACK. IN ITS FINAL FORM HPACK WILL HAVE THE USUAL MACINTOSH USER INTERFACE, NOT THE CURRENT COMMAND-LINE ONE. THE CURRENT VERSION HAS BEEN RELEASED MAINLY TO PROVIDE A MEANS OF TRANSFERRING ARCHIVES TO/FROM THE MAC (and also to persuade someone to add a Mac interface to it :-). Important note: When working on a port like this, never promise to buy everyone in the room pizza if it works the first time you run it. Running HPACK: Amiga ==================== The Amiga HPACK is virtually identical to the generic Unix-like command-line version. Unfortunately, due to lack of access to Amiga hardware, this version hasn't been tested much (if someone gives me an A4000 I'll test it to death, I promise). When compiling the code, Lattice C will give about half a dozen warnings per file about function return value mismatches, and conversion from const pointer to non-const or volatile blah blah blah. These are just Lattice C being Lattice C and can be ignored. The problem can be fixed by removing all 'const' keywords, not using any of the compiler built-in functions (memset, strcpy, etc), and ignoring the fact that it doesn't like returning an int + constant from an int-valued function. In addition, Lattice C has a number of code generation bugs which HPACK must work around. Basically the Amiga HPACK exists despite of Lattice C rather than because of it. Newer versions of SAS/C are somewhat better in this respect. Running HPACK: Archimedes ========================= The Archimedes HPACK is virtually identical to the generic Unix-like command-line version. The main extra feature is the addition of the +invert command which will convert paths like dir/file.c and dir/file.h to dir.c.file and dir.h.file, saving a lot of manual work when extracting archives created on other systems. When compiling the code, Arm C will give several warnings for some files about type conversions, which can either be worked around with expressions like a = ( int ) ( ( int ) b + ( int ) c ) ), or ignored. As with the Amiga version, I couldn't do too much testing on this one. Running HPACK: Atari ST ======================= This version is, like most other versions, identical to the standard Unix command-line version. There are in fact two executables, one for 68000 systems and one for 68030 systems. To compile HPACK for the Atari ST, use the Pure C project files in the system directory. Ghod it's slow! =============== I know - it's difficult to have both speed and portability (or to rehash an old saying: "Fast, portable, good - choose any two"). HPACK can never really compete with 'one-platform wonder' archivers which are highly tuned for a particular system. HPACK has been tuned for compression performance, not speed - it is recommended that, if the OS supports it, it be run in the background with the [-s]tealth mode switch. Where to get HPACK: =================== The latest version of HPACK should always be available from the following BBS systems and archive sites: Phone: +49 234 770457 Connection: V.32bis/V.42bis + fax G3 incl. v.17 Sysop: Peter Sowa FIDO address: 2:245/302.7 Comment: This BBS contains the German versions of the HPACK executables. Note that since communcation is by snail mail, new releases may take a while to appear. Name: Fire&Ice CBCS Phone: +61 2 339 5545 Connection: Telebit Trailblaser TR100 Mk2 Sysop: Jonathan Michaels <jonathan@asstdc.oz.au> Location: Sydney, NSW, Australia The src.doc.ic.ac.uk (146.169.2.1) archive site. This site contains the complete HPACK collection and is probably the best place to look for it. The garbo.uwasa.fi (128.214.87.1) archive site and all garbo mirror sites worldwide. This is updated a few weeks after the UK site to allow potential bugfixes to be made. Availability of HPACK for Other Systems: ======================================== Anyone want to port HPACK to their particular pet system? It's about 900K of ANSI C code, with some low-level system I/O thrown in to confuse you (through some mysterious process this amount increases by about 10K a week, so get it now before it gets too much). A knowledge of assembly language is probably necessary on low-end systems to speed up a few of the core compression routines. If you want to port it to any other system, drop me a line..... International Versions of HPACK: ================================ All the text strings contained within HPACK are generated from a definitions file via a preprocessing tool. To create versions of HPACK in other languages, all that is necessary is to translate the text in the definitions file and run it through the preprocessor. HPACK will dynamically adjust itself at runtime to the currently selected locale. The definitions file is available on request from the HPACK author, or as part of the generic source code distribution. Currently Bavarian, English, German, Dutch, Italian, Polish, Spanish, and Swiss versions exist. Security of HPACK Authentication/Encryption: ============================================ There has been some talk recently on how trivial it is to break the authentication/encryption used by many archivers (for example the "authentication" used in the long-awaited version 2 of a popular archiver was touted as being "greatly strengthened", meaning it took all of an hour to break after it first appeared). To answer any worries about the security of HPACK encryption/authentication, I have included with the source code distribution two sample archives, data/crypt.hpk and data/secure.hpk, for which I offer the following challenge: SECURE.HPK contains a single stored file called SAMPLE.TXT dated 1st May 1992, with the file itself containing the text '01234567890123456789'. I challenge anyone to alter this archive in any way and yet retain the valid signature (that is, HPACK when checking it should report that it still contains my valid signature). Alternatively, I challenge anyone to create an HPACK archive which contains a forged signature from me. Sample signature generation/checking code is included in the HPACK source. CRYPT.HPK contains twenty conventional-key encrypted text files which contain 2 lines each of HPACK.DOC, beginning at the start of the document (for a total of 40 lines worth of plaintext). The encryption password is a simple lowercase-only English phrase, and is identical for all twenty files. The nature of the data is such that most of it won't even be compressed - it'll be stored as is. These conditions reflect the absolute worst-case situation in archive encryption, where the attacker knows the encrypted plaintext, the password is relatively simple, and HPACK's most insecure encryption method is used (this provides a realistic basis for an attack on the encryption. Any encryption method, no matter how bad, can be made to appear secure if the initial conditions are biased enough). I challenge anyone to provide me with either the passphrase used to encrypt the data, or to encrypt the next 2 lines of HPACK.DOC in such a way that they can be decrypted with the password. Sample en/decryption code is available as part of HPACK or a I will email anyone who requests it a reference implementation in C. In addition I will encrypt any data you like with the given passphrase, if this will help in trying to break the encryption. In fact I'll do anything short of revealing the password if this helps with an attack on the encryption. Finally, I will make the password available after some reasonable period of time, say 6 months, so users can reassure themselves that it is indeed a genuine password and not some fake garbled mess cooked up just to make the encryption look good. The attacks can be mounted on any computer system using any amount of CPU power and/or custom hardware. More details on the merits of the encryption/authentication algorithms, along with possible methods of attack, are given in the file hpackext.doc. Credits: ======== Thanks to the following people for helping in HPACK: Stuart Woolford for the Unix port and endless arguments about the code. Conrad Bullock and John Burnell for the OS/2 port. Martin Braschler for the Atari ST port Stuart Woolford and John Burnell for tirelessly finding bugs and making many helpful suggestions. All the people listed in the makefile for moving it to their version of Unix and providing feedback. Steven Perreau, Hexen Hammer, and David Dix for providing a discussion (read: flaming argument) forum for HPACK developers on their BBS's over the years. Arrigo Triulzi for providing the Italian translation of HPACK. Peter de Vocht for providing the Dutch translation of HPACK. Peter Sowa for providing the German translation of HPACK. Rafal Mazkowski for providing the Polish translation of HPACK. Eduardo Jacob for providing the Spanish translation of HPACK. Martin Braschlet for providing the Swiss German translation of HPACK. DaviD W. Sanderson for cleaning up and improving the original HPACK manpage and getting it to work properly. PurpleX for putting up with many silly questions and sarcastic remarks about the Mac API. Nick Little for compiling HPACK on an Amiga 500 using Lattice C (wow!) TMOTA and Edouard Poor for compiling HPACK on the Archimedes. Chris Gransden for finding all the bugs I put into the Archimedes port and for testing the constant stream of fixes I sent him. Philip Zimmermann for letting me steal his ideas (and in some cases code) from the PGP encryption program. Lutz Frank for letting me use his 680x0 assembly-language primitives. Joerg Plate for getting the code going with SAS/C 6.2 on the Amiga and making all sorts of changes and fixes. Bancroft Scott provided much technical assistance on ASN.1 and its various encoding rules (BER/DER/CER/PER). All kcbbs users for putting up with endless stirring about HPACK. The HPACK Curse: ================ In early June 1992 one of the Mac HPACKers downloaded a new release of the code from a BBS. Shortly thereafter his hard drive died, taking multiple megabytes of data with it and incapacitating his Mac. He logged onto another BBS which had an HPACK forum and complained about this. After he logged off, the VT100 he was using to complain also expired. In mid-August 1992 an attempt was made to place a copy of the DOS HPACK executable on an ftp site for pickup by someone interested in it. Shortly before it was to take place, the machines which were to be used were unexpectedly shut down for four days for power maintenance. Once they were back up, the comms machine which handled all ftp traffic became unstable due to a mysterious hardware problem. This problem remained in evidence for several weeks. In late September 1992 the Amiga 500 being used to compile the Amiga HPACK was destroyed by a power-line spike, and was only brought back to life some months later. In October 1992 the Atari ST hard drive on which the Atari HPACK was being stored crashed for the last time. This is an interesting case in which the hardware exhibited a limited degree of precognizance, having crashed several times even before HPACK was installed. In November 1992 the Imperial College Maths RS6000 cluster crashed 7 times in a row while the Italian translation of the text was being prepared - and then the IBM field circus that came to upgrade the systems couldn't because it didn't look like the picture in their manuals. In January 1993 the HPACK curse hit the I/O controller on the Atari ST being used to redo the Atari port, disabling the keyboard and mouse and thus rendering it inoperative. In February 1993 the person who did the HPACK Unix port was at work when one of the secretaries tried to reboot her machine after a system crash. It refused to reboot - the hard drive had died. Shortly thereafter, their network went down. Someone (or something) had removed an ethernet terminator.... but there was noone in the room at the time. A little later, another one of the secretaries couldn't read any data off a backup disk. Closer inspection revealed that the drive had been mounted upside down.... but it was working fine a few hours earlier, and noone capable of doing the job had been near the machine. Then he realised it: He was carrying a Zoo'd (not HPACK'd) copy of the HPACK source code around with him.... Does this mean HPACK is cursed? Find out more in the next release (and wait with baited breath for the full story of a 5am logon on a local BBS by someone (or something) which would only identify itself as 'hpack', and for which the call came from no known phone number). HPACK as a Compiler Test: ========================= The HPACK source code may be useful as a benchmark for compilers, as it has displayed an amazing ability to unearth compiler bugs. It has turned up a bug in TurboC/TurboC++/BorlandC++ under MSDOS, bugs all over Lattice C (mainly in the code generator) on the Amiga, a bug in the Sun acc compiler, a bug in the Xenix cc, a bug in the RS6000 cc optimizer, a bug in the Amiga DICE compiler preprocessor, and has managed to break the optimizers in TopSpeed C, Watcom C, the Irix cc, Ultrix vcc, and Arm C. Various sarcastic comments on the compilers in question are present in code workarounds at various places (except for the RS6000 cc, whose optimzer is too awesome to criticize even if it does generate incorrect code). It has been suggested that all C compilers should be made to carry a "Safe for use with HPACK" rating. The HPACK Warranty: =================== 1. Customer Obligations ----------------------- 1.1. Customer assumes full responsibility that this program meets the specifications, capacity, capabilities, and other requirements of said customer, and agrees not to bother the author if the program does not perform as expected, or performs other than expected, or does not perform at all. 1.2. Customer assumes full responsibility for any deaths or injuries that may result from the normal or abnormal operation of this program. In the event of casualties exceeding 1000 persons or property damage in excess of $10 million, customer agrees that he or she has stolen the program and we didn't even know he or she had it. 1.3. Customer agrees not to say bad things about the program or the author to anyone claiming to be from "60 Minutes". 2. Very Limited Warranty and Conditions of Sale ------------------------------------------------ 2.1. For a period of 90 minutes, commencing from the time you first thought about getting this program, we warrant that this program may or may not be free of any manufacturing defects. It will be replaced during the warranty period upon payment of an amount equal to the original purchase price plus $10.00 for handling. This warranty is void if the program has been examined or run by the user, or if the manual has been read. 2.2. This program is sold on an AS WAS basis. The author makes no warranty that it is, in fact, what we say it is in our propaganda, or that it will perform any useful function. We have no obligation whatsoever other than to provide you with this fine disclaimer. 2.3. Some countries do not allow limitations as to how long an implied warranty lasts, so we refuse to imply anything. 2.4. There is an extremely small but nonzero chance that, through a process known as "tunnelling", this program may spontaneously disappear from its present location and reappear at any random place in the universe, including your neighbours computer system. The author will not be responsible for any damages or inconvenience that may result. 3. Limitation of Liability -------------------------- 3.1. We have no liability or responsibility to the customer, the customers agents, our creditors, your creditors, or anyone else. ------------------------- Testimony from one of our satisfied customers: "I hear this crash and I find a rock, wrapped in paper, next to my living room window. I open up the note and it says, 'You want it in writing? You got it. Next time, use a *real* archiver. HPACK. We know where you live'." So why aren't *you* using HPACK? ------------------------- Here's what reviewers have been saying about HPACK: "Version 0.79 has several of the advanced features recommended in version 0.78, but not all of the ones I'd like to see in version 0.80. So, it's pretty good except when it's not. Three stars. You probably won't use half the original features anyway. I'm a little ticked off that it clashes with my most exotic memory-resident programs, but otherwise the software runs just fine on my Turbo Rambuster 486. It will probably run like molasses on your XT. It's great value at $25, and I recommend you register it, although that's easy for me to say because reviewers get freebies".