home *** CD-ROM | disk | FTP | other *** search
- Chaos Digest Lundi 12 Avril 1993 Volume 1 : Numero 18
-
- Editeur: Jean-Bernard Condat (jbcondat@attmail.com)
- Archiviste: Yves-Marie Crabbe
- Co-Redacteurs: Arnaud Bigare, Stephane Briere
-
- TABLE DES MATIERES, #1.18 (12 Avril 1993)
- File 1--Cryptographie a clef publique: PGP
-
- Chaos Digest is a weekly electronic journal/newsletter. Subscriptions are
- available at no cost by sending a message to:
- linux-activists-request@niksula.hut.fi
- with a mail header or first line containing the following informations:
- X-Mn-Admin: join CHAOS_DIGEST
-
- The editors may be contacted by voice (+33 1 47874083), fax (+33 1 47877070)
- or S-mail at: Jean-Bernard Condat, Chaos Computer Club France [CCCF], B.P.
- 155, 93404 St-Ouen Cedex, France.
-
- Issues of ChaosD can also be found on some French BBS. Back issues of
- ChaosD can be found on the Internet as part of the Computer underground
- Digest archives. They're accessible using anonymous FTP from:
-
- * kragar.eff.org [192.88.144.4] in /pub/cud/chaos
- * uglymouse.css.itd.umich.edu [141.211.182.91] in /pub/CuD/chaos
- * halcyon.com [192.135.191.2] in /pub/mirror/cud/chaos
- * ftp.cic.net [192.131.22.2] in /e-serials/alphabetic/c/chaos-digest
- * ftp.ee.mu.oz.au [128.250.77.2] in /pub/text/CuD/chaos
- * nic.funet.fi [128.214.6.100] in /pub/doc/cud/chaos
- * orchid.csv.warwick.ac.uk [137.205.192.5] in /pub/cud/chaos
-
- CHAOS DIGEST is an open forum dedicated to sharing French information among
- computerists and to the presentation and debate of diverse views. ChaosD
- material may be reprinted for non-profit as long as the source is cited.
- Some authors do copyright their material, and they should be contacted for
- reprint permission. Readers are encouraged to submit reasoned articles in
- French, English or German languages relating to computer culture and
- telecommunications. Articles are preferred to short responses. Please
- avoid quoting previous posts unless absolutely necessary.
-
- DISCLAIMER: The views represented herein do not necessarily represent
- the views of the moderators. Chaos Digest contributors
- assume all responsibility for ensuring that articles
- submitted do not violate copyright protections.
-
- ----------------------------------------------------------------------
-
- Date: Wed Mar 24 15:03:59 CDT 1993
- From: celma_s@epita.fr (Samuel Celma )
- Subject: File 1--Cryptographie a clef publique: PGP
-
-
- Phil Zimmerman's PGP (Pretty Good Privacy)
- Public Key Encryption for the Masses
-
-
- [ PGP Documentation extracts ]
-
- What is PGP?
-
- Pretty Good(tm) Privacy (PGP), from Phil's Pretty Good Software, is a
- high security cryptographic software application for MSDOS, Unix,
- VAX/VMS, and other computers. PGP allows people to exchange files or
- messages with privacy, authentication, and convenience. Privacy
- means that only those intended to receive a message can read it.
- Authentication means that messages that appear to be from a
- particular person can only have originated from that person.
- Convenience means that privacy and authentication are provided
- without the hassles of managing keys associated with conventional
- cryptographic software. No secure channels are needed to exchange
- keys between users, which makes PGP much easier to use. This is
- because PGP is based on a powerful new technology called "public key"
- cryptography.
-
- PGP combines the convenience of the Rivest-Shamir-Adleman (RSA)
- public key cryptosystem with the speed of conventional cryptography,
- message digests for digital signatures, data compression before
- encryption, good ergonomic design, and sophisticated key management.
- And PGP performs the public-key functions faster than most other
- software implementations. PGP is public key cryptography for the
- masses.
-
- PGP does not provide any built-in modem communications capability.
- You must use a separate software product for that.
-
- Why Do You Need PGP?
-
- It's personal. It's private. And it's no one's business but yours.
- You may be planning a political campaign, discussing your taxes, or
- having an illicit affair. Or you may be doing something that you
- feel shouldn't be illegal, but is. Whatever it is, you don't want
- your private electronic mail (E-mail) or confidential documents read
- by anyone else. There's nothing wrong with asserting your privacy.
- Privacy is as apple-pie as the Constitution.
-
- Perhaps you think your E-mail is legitimate enough that encryption is
- unwarranted. If you really are a law-abiding citizen with nothing to
- hide, then why don't you always send your paper mail on postcards?
- Why not submit to drug testing on demand? Why require a warrant for
- police searches of your house? Are you trying to hide something?
- You must be a subversive or a drug dealer if you hide your mail
- inside envelopes. Or maybe a paranoid nut. Do law-abiding citizens
- have any need to encrypt their E-mail?
-
- What if everyone believed that law-abiding citizens should use
- postcards for their mail? If some brave soul tried to assert his
- privacy by using an envelope for his mail, it would draw suspicion.
- Perhaps the authorities would open his mail to see what he's hiding.
- Fortunately, we don't live in that kind of world, because everyone
- protects most of their mail with envelopes. So no one draws suspicion
- by asserting their privacy with an envelope. There's safety in
- numbers. Analogously, it would be nice if everyone routinely used
- encryption for all their E-mail, innocent or not, so that no one drew
- suspicion by asserting their E-mail privacy with encryption. Think
- of it as a form of solidarity.
-
- Today, if the Government wants to violate the privacy of ordinary
- citizens, it has to expend a certain amount of expense and labor to
- intercept and steam open and read paper mail, and listen to and
- possibly transcribe spoken telephone conversation. This kind of
- labor-intensive monitoring is not practical on a large scale. This
- is only done in important cases when it seems worthwhile.
-
- More and more of our private communications are being routed through
- electronic channels. Electronic mail will gradually replace
- conventional paper mail. E-mail messages are just too easy to
- intercept and scan for interesting keywords. This can be done
- easily, routinely, automatically, and undetectably on a grand scale.
- International cablegrams are already scanned this way on a large
- scale by the NSA.
-
- We are moving toward a future when the nation will be crisscrossed
- with high capacity fiber optic data networks linking together all our
- increasingly ubiquitous personal computers. E-mail will be the norm
- for everyone, not the novelty it is today. Perhaps the Government
- will protect our E-mail with Government-designed encryption
- protocols. Probably most people will trust that. But perhaps some
- people will prefer their own protective measures.
-
- Senate Bill 266, a 1991 omnibus anti-crime bill, had an unsettling
- measure buried in it. If this non binding resolution had become real
- law, it would have forced manufacturers of secure communications
- equipment to insert special "trap doors" in their products, so that
- the Government can read anyone's encrypted messages. It reads: "It
- is the sense of Congress that providers of electronic communications
- services and manufacturers of electronic communications service
- equipment shall insure that communications systems permit the
- Government to obtain the plain text contents of voice, data, and
- other communications when appropriately authorized by law." This
- measure was defeated after rigorous protest from civil libertarians
- and industry groups. But the Government has since introduced other
- disturbing legislation to work toward similar objectives.
-
- If privacy is outlawed, only outlaws will have privacy. Intelligence
- agencies have access to good cryptographic technology. So do the big
- arms and drug traffickers. So do defense contractors, oil companies,
- and other corporate giants. But ordinary people and grassroots
- political organizations mostly have not had access to affordable
- "military grade" public-key cryptographic technology. Until now.
-
- PGP empowers people to take their privacy into their own hands.
- There's a growing social need for it. That's why I wrote it.
-
- Legal Issues
-
- Trademarks, Copyrights, and Warranties
- --------------------------------------
-
- "Pretty Good Privacy", "Phil's Pretty Good Software", and the "Pretty
- Good" label for computer software and hardware products are all
- trademarks of Philip Zimmermann and Phil's Pretty Good Software. PGP
- is (c) Copyright Philip R. Zimmermann, 1990-1993. Philip Zimmermann
- also holds the copyright for the PGP User's Manual, as well as any
- foreign language translations of the manual or the software.
-
- The author assumes no liability for damages resulting from the use of
- this software, even if the damage results from defects in this
- software, and makes no representations concerning the merchantability
- of this software or its suitability for any specific purpose. It is
- provided "as is" without express or implied warranty of any kind.
-
-
- Patent Rights on the Algorithms
- -------------------------------
-
- When I first released PGP, I half-expected to encounter some form of
- legal harassment from the Government. Indeed, there has been legal
- harassment, but it hasn't come from the Government-- it has come
- from a private corporation.
-
- The RSA public key cryptosystem was developed at MIT with Federal
- funding from grants from the National Science Foundation and the
- Navy. It is patented by MIT (U.S. patent #4,405,829, issued 20 Sep
- 1983). A company in California called Public Key Partners (PKP) holds
- the exclusive commercial license to sell and sub-license the RSA
- public key cryptosystem:
-
-
- +++++
- XRPX Acc No: N83-178106
- Cryptographic communication system has encoding and decoding devices
- coupled to memory so that data words may be stored ensuring file
- integrity
- Patent Assignee: (MASI ) MASSACHUSETTS INST TECH
- Author (Inventor): RIVEST R L; SHAMIR A; ADLEMAN L M
- Number of Patents: 001
- Patent Family:
- CC Number Kind Date Week
- US 4405829 A 830920 8340 (Basic)
- Priority Data (CC No Date): US 860586 (771214)
- Abstract (Basic): The system includes a communications channel coupled to
- at least one terminal having an encoding device and to at least one
- terminal having a decoding device. A message-to-be-transferred is
- enciphered to ciphertext at the encoding terminal by encoding the
- message as a number M in a predetermined set. That number is then
- raised to a first predetermined power (associated with the intended
- receiver) and finally computed. The remainder or residue, C, is
- computed when the exponentiated number is divided by the product of two
- predetermined prime numbers (associated with the intended receiver).
- The residue C is the ciphertext. The ciphertext is decipheres to
- the original message at the decoding terminal in a similar manner by
- raising the ciphertext to a second predetermined power (associated with
- the intended receiver). The residue, M', is computed when the
- exponentiated ciphertext is divided by the product of the two
- predetermined prime numbers associated with the intended receiver. The
- residue M' corresponds to the original encoded message M. (12pp.)
- Int Pat Class: H04K-001/00; H04L-009/04
- +++++
-
-
- The author of this software implementation of the RSA algorithm is
- providing this implementation for educational use only. Licensing this
- algorithm from PKP is the responsibility of you, the user, not Philip
- Zimmermann, the author of this software implementation. The author
- assumes no liability for any patent infringement that may result from
- the unlicensed use by the user of the underlying RSA algorithm used in
- this software.
-
- Unfortunately, PKP is not offering any licensing of their RSA patent
- to end users of PGP. This essentially makes PGP contraband in the
- USA. Jim Bidzos, president of PKP, threatened to take legal action
- against me unless I stop distributing PGP, until they can devise a
- licensing scheme for it. I agreed to this, since PGP is already in
- wide circulation and waiting a while for a licensing arrangement from
- PKP seemed reasonable. Mr. Bidzos assured me (he even used the word
- "promise") several times since the initial 5 June 91 release of PGP
- that they were working on a licensing scheme for PGP. Apparently, my
- release of PGP helped provide the impetus for them to offer some sort
- of a freeware-style license for noncommercial use of the RSA
- algorithm. However, in December 1991 Mr. Bidzos said he had no plans
- to ever license the RSA algorithm to PGP users, and denied ever
- implying that he would. Meanwhile, I have continued to refrain from
- distributing PGP, although I continue to update the PGP User's Guide,
- and have provided the design guidance for new revisions of PGP.
- Ironically, all this legal controversy from PKP has imparted a
- forbidden flavor to PGP that has only served to amplify its universal
- popularity.
-
- I wrote my PGP software from scratch, with my own implementation of
- the RSA algorithm. I didn't steal any software from PKP. Before
- publishing PGP, I got a formal written legal opinion from a patent
- attorney with extensive experience in software patents. I'm
- convinced that publishing PGP the way I did does not violate patent
- law. However, it is a well known axiom in the US legal system that
- regardless of the law, he with the most money and lawyers prevails,
- if not by actually winning then by crushing the little guy with legal
- expenses.
-
- Not only did PKP acquire the exclusive patent rights for the RSA
- cryptosystem, which was developed with your tax dollars, but they
- also somehow acquired the exclusive rights to three other patents
- covering rival public key schemes invented by others, also developed
- with your tax dollars. This essentially gives one company a legal
- lock in the USA on nearly all practical public key cryptosystems.
- They even appear to be claiming patent rights on the very concept of
- public key cryptography, regardless of what clever new original
- algorithms are independently invented by others. And you thought
- patent law was designed to encourage innovation! PKP does not
- actually develop any software-- they don't even have an engineering
- department-- they are essentially a litigation company.
-
- Public key cryptography is destined to become a crucial technology in
- the protection of our civil liberties and privacy in our increasingly
- connected society. Why should the Government try to limit access to
- this key technology, when a single monopoly can do it for them?
-
- It appears certain that there will be future releases of PGP,
- regardless of the outcome of licensing problems with Public Key
- Partners. If PKP does not license PGP, then future releases of PGP
- might not come from me. There are countless fans of PGP outside the
- US, and many of them are software engineers who want to improve PGP
- and promote it, regardless of what I do. The second release of PGP
- was a joint effort of an international team of software engineers,
- implementing enhancements to the original PGP with design guidance
- from me. It was released by Branko Lankester in The Netherlands and
- Peter Gutmann in New Zealand, out of reach of US patent law.
- Although released only in Europe and New Zealand, it spontaneously
- spread to the USA without help from me or the PGP development team.
-
- The IDEA(tm) conventional block cipher used by PGP is covered by a
- patent in Europe, held by ETH and a Swiss company called Ascom-Tech
- AG. The patent number is PCT/CH91/00117. International patents are
- pending. IDEA(tm) is a trademark of Ascom-Tech AG. There is no
- license fee required for noncommercial use of IDEA. Ascom Tech AG
- has granted permission for PGP to use the IDEA cipher, and places no
- restrictions on using PGP for any purpose, including commercial use.
- You may not extract the IDEA cipher from PGP and put it in another
- commercial product without a license. Commercial users of IDEA may
- obtain licensing details from Dieter Profos, Ascom Tech AG, Solothurn
- Lab, Postfach 151, 4502 Solothurn, Switzerland, Tel +41 65 242885,
- Fax +41 65 235761.
-
- The ZIP compression routines in PGP come from freeware source code,
- with the author's permission. I'm not aware of any patents on the
- ZIP algorithm, but you're welcome to check into that question
- yourself. If there are any obscure patent claims that apply to ZIP,
- then sorry, you'll have to take care of the patent licensing, not me.
-
- All this patent stuff reminds me of a Peanuts cartoon I saw in the
- newspaper where Lucy showed Charlie Brown a fallen autumn leaf and
- said "This is the first leaf to fall this year." Charlie Brown said,
- "How do you know that? Leaves have been falling for weeks." Lucy
- replied, "I had this one notarized."
-
- Licensing and Distribution
- --------------------------
-
- In the USA PKP controls, through US patent law, the licensing of the
- RSA algorithm. But I have no objection to anyone freely using or
- distributing my PGP software, without payment of fees to me. You must
- keep the copyright notices on PGP and keep this documentation with
- it. However, if you live in the USA, this may not satisfy any legal
- obligations you may have to PKP for using the RSA algorithm as
- mentioned above.
-
- In fact, if you live in the USA, and you are not a Federal agency,
- you shouldn't actually run PGP on your computer, because Public Key
- Partners wants to forbid you from running my software. PGP is
- contraband.
-
- PGP is not shareware, it's freeware. Forbidden freeware. Published
- as a community service. If I sold PGP for money, then I would get
- sued by PKP for using their RSA algorithm. More importantly, giving
- PGP away for free will encourage far more people to use it, which
- hopefully will have a greater social impact. This could lead to
- widespread awareness and use of the RSA public key cryptosystem,
- which will probably make more money for PKP in the long run. If only
- they could see that.
-
- All the source code for PGP is available for free under the "Copyleft"
- General Public License from the Free Software Foundation (FSF). A
- copy of the FSF General Public License is included in the source
- release package of PGP.
-
- The PGP version 2.2 executable object release package for MSDOS
- contains the PGP executable software, documentation, sample key rings
- including my own public key, and signatures for the software and this
- manual, all in one PKZIP compressed file called PGP22.ZIP. The PGP
- source release package for MSDOS contains all the C source files in
- one PKZIP compressed file called PGP22SRC.ZIP.
-
- You may obtain free copies or updates to PGP from thousands of BBS's
- worldwide or from other public sources such as Internet FTP sites.
- Don't ask me for a copy directly from me, since I'd rather avoid
- further legal problems with PKP at this time. I might be able to
- tell you where you can get it, however.
-
- If you have access to the Internet, watch for announcements of new
- releases of PGP on the Internet newsgroups "sci.crypt" and PGP's own
- newsgroup, "alt.security.pgp". There is also an interest group
- mailing list called info-pgp, which is intended for users without
- access to the "alt.security.pgp" newsgroup. Info-pgp is moderated by
- Hugh Miller, and you may subscribe to it by writing him a letter at
- info-pgp-request@lucpul.it.luc.edu. Include your name and Internet
- address. If you want to know where to get PGP, Hugh can send you a
- list of Internet FTP sites and BBS phone numbers. Hugh may also be
- reached at hmiller@lucpul.it.luc.edu.
-
- Export Controls
- ---------------
-
- The Government has made it illegal in many cases to export good
- cryptographic technology, and that may include PGP. They regard this
- kind of software as munitions. This is determined by volatile State
- Department policies, not fixed laws. I will not export this software
- out of the US or Canada in cases when it is illegal to do so under US
- State Department policies, and I assume no responsibility for other
- people exporting it on their own.
-
- If you live outside the US or Canada, I advise you not to violate US
- State Department policies by getting PGP from a US source. Since
- thousands of domestic users got it after its initial publication, it
- somehow leaked out of the US and spread itself widely abroad, like
- dandelion seeds blowing in the wind. If PGP has already found its
- way into your country, then I don't think you're violating US export
- law if you pick it up from a source outside of the US.
-
- It seems to some legal observers I've talked with, that the framers of
- the US export controls never envisioned that they would ever apply to
- cryptographic freeware that has been published and scattered to the
- winds. It's hard to imagine a US attorney trying to build a real
- case against someone for the "export" of software published freely in
- the US. As far as anyone I've talked to knows, it's never been done,
- despite numerous examples of export violations. I'm not a lawyer and
- I'm not giving you legal advice-- I'm just trying to point out what
- seems like common sense.
-
- Starting with PGP version 2.0, the release point of the software has
- been outside the US, on publicly-accessible computers in Europe.
- Each release is electronically sent back into the US and posted on
- publicly-accessible computers in the US by PGP privacy activists in
- foreign countries. There are some restrictions in the US regarding
- the import of munitions, but I'm not aware of any cases where this
- was ever enforced for importing cryptographic software into the US.
- I imagine that a legal action of that type would be quite a spectacle
- of controversy.
-
- Some foreign governments impose serious penalties on anyone inside
- their country for merely using encrypted communications. In some
- countries they might even shoot you for that. But if you live in
- that kind of country, perhaps you need PGP even more.
-
- Computer-Related Political Groups
-
- PGP is a very political piece of software. It seems appropriate to
- mention here some computer-related activist groups. Full details on
- these groups, and how to join them, is provided in a separate
- document file in the PGP release package.
-
- The Electronic Frontier Foundation (EFF) was founded in July, 1990,
- to assure freedom of expression in digital media, with a particular
- emphasis on applying the principles embodied in the Constitution and
- the Bill of Rights to computer-based communication. They can be
- reached at: Electronic Frontier Foundation, 238 Main Street,
- Cambridge, MA 02142, USA.
-
- The League for Programming Freedom (LPF) is a grass-roots organization
- of professors, students, businessmen, programmers and users dedicated
- to bringing back the freedom to write programs. They regard patents
- on computer algorithms as harmful to the US software industry. They
- can be reached at (617) 433-7071, or send Internet mail to
- lpf@uunet.uu.net
-
- Computer Professionals For Social Responsibility (CPSR) empowers
- computer professionals and computer users to advocate for the
- responsible use of information technology and empowers all who use
- computer technology to participate in public policy debates on the
- impacts of computers on society. They can be reached at:
- 415-322-3778 in Palo Alto, E-mail address cpsr@csli.stanford.edu.
-
- For more details on these groups, see the accompanying document in
- the PGP release package.
-
- Recommended Introductory Readings
-
- 1. Dorothy Denning, "Cryptography and Data Security", Addison-Wesley,
- Reading, MA 1982
- 2. Dorothy Denning, "Protecting Public Keys and Signature Keys",
- IEEE Computer, Feb 1983
- 3. Martin E. Hellman, "The Mathematics of Public-Key Cryptography,"
- Scientific American, Aug 1979
-
- Other Readings
-
- 4. Ronald Rivest, "The MD5 Message Digest Algorithm", MIT Laboratory
- for Computer Science, 1991
- 5. Xuejia Lai, "On the Design and Security of Block Ciphers",
- Institute for Signal and Information Processing, ETH-Zentrum,
- Zurich, Switzerland, 1992
- 6. Xuejia Lai, James L. Massey, Sean Murphy, "Markov Ciphers and
- Differential Cryptanalysis", Advances in Cryptology- EUROCRYPT'91
- 7. Philip Zimmermann, "A Proposed Standard Format for RSA
- Cryptosystems", Advances in Computer Security, Vol III, edited by
- Rein Turn, Artech House, 1988
- 8. Paul Wallich, "Electronic Envelopes", Scientific American, Feb
- 1993, pages 30-32. (This is an article on PGP)
-
- About the Author
-
- Philip Zimmermann is a software engineer consultant with 18 years
- experience, specializing in embedded real-time systems, cryptography,
- authentication, and data communications. Experience includes design
- and implementation of authentication systems for financial
- information networks, network data security, key management
- protocols, embedded real-time multitasking executives, operating
- systems, and local area networks.
-
- Custom versions of cryptography and authentication products and
- public key implementations such as the NIST DSS are available from
- Zimmermann, as well as custom product development services. His
- consulting firm's address is:
-
- Mr. Philip Zimmermann
- Boulder Software Engineering
- 3021 Eleventh Street
- Boulder, Colorado 80304 USA
- Phone 303-541-0140 (voice or FAX) (10:00am - 7:00pm Mountain Time)
- Internet: prz@sage.cgd.ucar.edu
-
- Where to Get PGP
-
- Finland: nic.funet.fi (128.214.6.100)
- Directory: /pub/unix/security/crypt/
-
- Italy: ghost.dsi.unimi.it (149.132.2.1)
- Directory: /pub/security/
-
- UK: src.doc.ic.ac.uk
- Directory: /computing/security/software/PGP
-
- For those lacking FTP connectivity to the net, nic.funet.fi also
- offers the files via email. Send the following mail message to
- mailserv@nic.funet.fi:
-
- ENCODER uuencode
- SEND pub/unix/security/crypt/pgp22src.zip
- SEND pub/unix/security/crypt/pgp22.zip
-
- This will deposit the two zipfiles, as (about) 15 batched messages in
- your mailbox within about 24 hours. Save and uudecode.
-
- PGP is also widely available on Fidonet, a large informal network of
- PC-based bulletin board systems interconnected via modems. Check
- your local bulletin board systems. It is available on many foreign
- and domestic Fidonet BBS sites.
-
- For information on PGP implementations on the Apple Macintosh,
- Commodore Amiga, or Atari ST, or any other questions about where to
- get PGP for any other platform, contact Hugh Miller at
- hmiller@lucpul.it.luc.edu.
-
- Here are a few people and their email addresses or phone numbers you
- can contact in some countries to get information on local PGP
- availability:
-
- Peter Gutmann Hugh Kennedy
- pgut1@cs.aukuni.ac.nz 70042.710@compuserve.com
- New Zealand Germany
-
- Branko Lankester Miguel Angel Gallardo
- lankeste@fwi.uva.nl gallardo@batman.fi.upm.es
- +31 2159 42242 (341) 474 38 09
- The Netherlands Spain
-
- Hugh Miller Colin Plumb
- hmiller@lucpul.it.luc.edu colin@nyx.cs.du.edu
- (312) 508-2727 Toronto, Ontario, Canada
- USA
-
- Jean-loup Gailly (21 av. mary, 92500 Rueil Malmaison, Tel.: 1-47518065)
- jloup@chorus.fr
- France
-
- ------------------------------
-
- End of Chaos Digest #1.18
- ************************************
-
- Downloaded From P-80 International Information Systems 304-744-2253
-