In RISKS-17.75, Peter Wayner noted the computer study done by Professor Donald Foster at Vassar College that attributed the writing style of the anonymously authored novel ``Primary Colors'' to Joe Klein, a Newsweek columnist and CBS commentator. Recently, Maureen Casey Owens, past president of the American Academy of Forensic Sciences, studied the handwritten notes on the amended typescript pages for the novel and concluded that the handwriting was most certainly that of Joe Klein. [Source: an article by David Streitfeld in *The Washington Post*, 17 July 1996] (An NPR program I heard at lunchtime on 17 Jul noted that other investigators had turned up the fact that Klein had recently paid cash for half of the price of his new house, seemingly having struck it rich in a short period of time.) On the same day, Random House finally admitted that Klein was indeed the author. Peter Wayner earlier had suggested in RISKS-17.75 that if Joe Klein were really trying to hide his identity, he would have disguised his writing style more assiduously. But we might suspect that Joe did not want to hide his identity completely, because the suspense has undoubtedly increased sales and paid for his house, and the having been identified will now dramatically increase his name-recognition index. On the other hand, Klein is now taking a lot of flak relating to his integrity as a journalist, because until now he has lied in denying authorship. Is it really true that all publicity is good publicity, even if it is bad publicity? So, you may ask, where is the RISKS relevance in this case? * RISKS readers are by now accustomed to being suspicious of purported computer evidence. Here, the winnowing out of Joe Klein's identity by Professor Foster is in retrospect very impressive. A case in which such evidence turns out to be actually correct is certainly worth mentioning, particularly because RISKS is sometimes criticized for including so many negative computer-related cases (a situation that occurs largely because we so seldom see real successes). Thus, there can be risks in *doubting* that digital evidence is truthful. But, above all, there are always risks in *believing* that digital evidence is truthful. * There is the risk of believing that you can reliably hide your identity, even in the presence of altered writing styles, veiled attacks on oneself (the novel contains ``an unflattering portrait of a reporter who resembles Klein, according to Streitfeld), various forms of steganography, spoofed e-mail, and a trustworthy senior editor. You must also beware of telephone records, credit-card records, airplane reservation databases, library records, nosy realtors, snoopy neighbors, coincidental encounters, etc. * The art of lying is very difficult. If you are going to attempt it, you must be prepared to be absolutely consistent forever, because otherwise inferences can be drawn that can smoke you out. However, absolute consistency is in general impossible, especially if the cover story is in any way inconsistent with perceivable reality. Cover stories with plausible deniability are best when they are also legitimate. However, with webservers and cross-linked databases, it is increasingly difficult to hide the rest of the story. Also, covert activities in the intelligence world are such that you must lie in denying the mere existence of a covert operation (which, *by definition* "does not exist"), and in the name of national security you must perjure yourself whenever you are challenged. So, beware of what can be gleaned from computer-related inferences -- especially when some of the information is perfectly above-board but perhaps not completely correct. In this case, the Klein battle to remain anonymous may seem to have turned inside out, but the situation is now really a Klein bottle in which secrecy and full disclosure are both on the same surface and ethics have become blurred with nonethics. Stay tuned for the Klein re-buttle. I'm not taking bet-tles. The only consistent course is clearly to avoid putting yourself in such a position in the first place. Although that might seem to preclude April Fools' spoofs, note that in our most famous cases (for example, the Chernenko and Spafford e-mail spoofs discussed in the RISKS archives and in my RISKS book), the prankster has unabashedly 'fessed up when confronted (Piet Beertema and Chuq von Rospach, respectively), and generally received admiration for his cleverness. (The negative responses that "Chernenko" took are also worth noting.) Similarly, Robert Morris never denied his involvement in the Internet Worm experiment that went seriously awry. So, perhaps it would have been OK for Klein to publish anonymously if he had admitted his authorship when first challenged? However, to expect that he could remain anonymous forever is totally unrealistic in our information-laden world, and that realization may color [!] future authors seeking similar subterfuges. On the other hand, to retain anonymity in order to further increase sales is either (1) morally reprehensible, or (2) just consistent with the emerging American Way -- anything is OK as long as you can get away with it, or (3) both 1 and 2. [Peter Wayner found the following quote in Media Circus on-line, referring to Maureen Casey Owens' analysis of the Klein typescript: Says Joshua Sostrin, "The analyst later concluded that the Declaration of Independence, as has long been suspected, was indeed penned by Bob Dole."]
Musings on the ever-increasing complexity of everyday life, triggered by the ever-increasing size of the "end-of-the-digest" announcement of the RISKS Digest: I am alternately amused and terrified by the ever-increasing complexity of everyday life. Technology provides more and more functions essential to our life. More and more artifacts pervade our lives and make themselves essential to our lifestyles. Many of the new technologies involve communication networks that interconnect large numbers of systems. These lead to an increase in the complexity of societal interactions and the sheer number of contacts among people. As a result, the number of potential weak points increase, and thereby the dangers. The ever-increasing amount of interactions among people, institutions, and governments gives ever-more opportunities for disaster, and the natural tendency of governments and institutions is to tackle each known problem by instituting rules, regulations, and laws to control the abuses. But these well-intentioned (and sometimes not so well intentioned) efforts simply proliferate to add yet more complexity to our lives. Those in computer science know how difficult it is to disentangle the interactions of a rule-based system. What happens when the rules are those of an institution or government, designed by multiple people over decades -- centuries? We have rules that interaction unplanned ways, rules that are inconsistent. Rules that are vague and ambiguous. Rules that were relatively clear and precise in the era they were developed, but become outmoded or imprecise with the passage of time and the invention of new technologies. We all know what the result is: unstable, unpredictable systems. Even my own home grows rapidly in complexity. 8+ remote controls to operate my home theatre/TV. An ever-increasing set of manuals for the ever-increasing number of home appliances. A dozen or so electric clocks to be reset when power fails and during the biannual summertime/regular time switch over. Items to be lubricated, adjusted, dusted, tested. batteries to be checked and replaced on a regular basis. Security precautions in the home and at work: identification badges, more secure driver's license, more secure $100 bills, and the ever proliferation of passwords --each to be non-words, each to be changed at frequent intervals. Even the RISKS Digest itself is not immune. Look at the end-of-the-digest announcement. Once this was a few lines, at the beginning of the digest. Then, people like me had problems with the FTP instructions, so the instructions were made more complete and precise -- but thereby longer. Then people like me kept asking for permission to reprint, so the announcement was modified to spell out the policy (which, of course, required inventing a policy). Soon, the number of items got so large that the whole thing was put at the rear of the digest, where it now takes up over a page of printed text. How long before it is two pages? How long before it rivals the size of the digest itself? [SEE NEXT ITEM. PGN] What's the RISK? Well, as life gets more and more complex, the number of interactions increases (as N-squared? faster?). The number of unexpected interactions also increases, usually with unknown impact. We have already seen how the interconnectedness of the phone systems and the electric utility systems means that single-point failures can sometimes bring down a large region of the country. I expect these instances to increase, both in number and in magnitude, as the number of interconnections increase. The real question is: are there alternatives or are we doomed to ever-increasing complexity? Don Norman. VP, Apple Research Labs firstname.lastname@example.org
Don, I am really glad you raised this issue. It is worthy of considerable discussion in RISKS. Not incidentally, a problem in the past is that RISKS gets distributed to net-lame places that cannot use the web or FTP or much else, or in some cases cannot even reply by e-mail. The full risks.info message kept growing in part to stave off all of the victims of noncompliant Internet service providers and sites without webservers. I too have been annoyed at the increasing volume of the risks info message. So, thanks to your urging, from now on new subscribers will continue to get the full info page initially when their subscription is acknowledged, and the regular end-of-issue item will be BRIEF. The full info message can be gotten by e-mail to risks-request@CSL.sri.com with the one line INFO, by ftp, and as a web page, and the brief message (see the end of this issue) states that "All contributors are assumed to have read the full info file." I hope that suffices. MANY THANKS for the prompt. PGN
PA News 7/10/96 12:39 PM <> A computer buff who downloaded the Marks & Spencer's security <>file containing pin numbers when he visited a London store to <>carry out maintenance, was ordered to complete 70 hours <>community service work today. <> Former Olivetti computer engineer Edward Yearley, 29, of <>Vicarage Lane, Bovingdon, Hemel Hempstead, Herts, was convicted <>in June of gaining unauthorised access to computer material in <>October 12 1994, under the Computer Misuse Act 1990. o Yearly posted the file to the "Gates of the Underworld" BBS where it was noticed in November. Police duly executed a search warrant on his home, seizing his PC and disks. Yearly denied belonging to the BBS, but his computer showed where he had uploaded the file under the pseudonym "Mr. Ed." <> After reading pre-sentence reports magistrate Paul Clark <>said: "There is an element of breach of trust here. It is fair <>to say a certain amount of knowledge and expertise is needed to <>commit an offence such as this." [DMK: I don't know whether to sigh or barf.] <> He added: "I'm satisfied there was no question of personal <>profit for you, no gain and no loss to Marks & Spencer. But <>the scope for other people to misuse the information that was <>downloaded is hard to judge." o Yearley was ordered to perform 70 hours of community service and pay UKP170 in cour costs. His computer will be returned to him. <> "Although your own personal computer was seized and evidence <>gathered from it, your own computer was not used for committing <>the offence or facilitating it." [DMK: Stealing the data in the first place and violating the Parker principle of Possession or posting it to the BBS and violating the principle of Confidentiality? Maybe I'll barf after all.] Dave Kennedy [CISSP] InfoSec Recon Team Chief, National Computer Security Assn
An article in the 10 Jul 1996 *San Francisco Chronicle* (p. A13 of the East Bay edition) describes a group of high-school students who broke into a drink manufacturer's voice-mail system, erased information, changed passwords, created new accounts for their own use, and eventually crashed the system through overuse. The article reports that the company had to spend $40,000 to bring in an outside technician and upgrade their software. A few questions remain. Should superuser functions like the creation of new users be allowed via the phone at all? How was the infiltration so pervasive that they couldn't just shut the system down, erase bogus accounts, and chance privileged passwords? I'm reminded of a similar, more limited, incident which occurred five or six years ago when my high school set up a voice mail system to keep parents informed of their children's homework assignments. There was a system-wide password to update the information, which was changed monthly for security reasons -- in January, it was 1111, in February it was 2222, and in December it was 1212. After the system was broken into, its administrator decided against changing the password. Her reasoning: it was near the end of the month, and the password would be changed soon, anyway. Tom Insel
18 July 1996 There is currently being circulated, to members of Congress and possibly elsewhere, a four page document entitled ``Brute-Force Cryptanalytic Attacks'' that calls into question some of the conclusions of the ``Minimum Key Lengths for Symmetric Ciphers'' white paper . The document bears no author or organization attribution, but we are told that it originated from NSA. The NSA document argues that ``physical realities'' make parallel key search much more expensive and time consuming than our white paper estimated. However, the NSA document appears to have been written from the perspective of general parallel processing or cryptanalysis rather than exhaustive key search per se. It ignores several elementary principles of parallel processing that apply specifically to exhaustive key search machines of the type that our white paper considered. In particular, NSA argues that interconnections, heat dissipation, input/output bandwidth, and interprocessor communication make it difficult to ``scale up'' a key search machine by dividing the task among a large number of small components. While these factors do limit the scalability of more general purpose multiprocessor computers (such as those made by Cray), they do not apply at all to specialized exhaustive key search machines. The NSA argument ignores the most fundamental feature of brute-force key search: the processors performing the search have no need to communicate with other components of the system while they perform their share of the search, and therefore the system has no need for any of the global interconnections that limit scaling. Indeed, there is no reason that all the components of a parallel search machine must be located even within the same city, let alone the same computer housing. We note that one of our co-authors (Eric Thompson, of Access Data, Inc.) designs and builds medium-scale FPGA-based key search machines with exactly this loosely-coupled structure, and regularly uses them to recover keys for clients that include the FBI. The NSA document also calls into question our cost estimates for ASIC components, suggesting that ASIC chips of this type cost NSA approximately $1000.00 each. However, our $10.00 per chip estimate is based on an actual price quote from a commercial chip fabrication vendor for a moderate-size order for an exhaustive search ASIC designed in 1993 by Michael Wiener . Perhaps NSA could reduce its own costs by changing vendors. Finally, the NSA report offers estimates of the time required to perform exhaustive search using a Cray model T3D supercomputer. This is a curious choice, for as our report notes, general-purpose supercomputers of this type make poor (and uneconomical) key search engines. However, even the artificially low performance results for this machine should give little comfort to the users of 56 bit keys. According to NSA, 56 bit keys can be searched on such a machine in less than 453 days. ``Moore's law'' predicts that it will not be long before relatively inexpensive general-purpose computers offer similar computational capability. /s/ Matt Blaze Whitfield Diffie References:  Blaze, M., Diffie, W., Rivest, R., Schneier, B., Shimomura, T., Thompson, E., and Wiener, M. ``Minimum Key Lengths for Symmetric Key Ciphers for Commercial Security.'' January 1996. Available from ftp://ftp.research.att.com/dist/mab/keylength.txt  Wiener, M. ``Exhaustive DES Key Search.'' Presented at Crypto-93, Santa Barbara, CA. August 1993. ========================================================================= [Transcription of document circulated to various members of congress and others in June, 1996, apparently by NSA] BRUTE-FORCE CRYPTANALYTIC ATTACKS Two published theoretical estimates of cost versus time to perform brute-force hardware attacks on selected cryptography key lengths differ between themselves and differ significantly from what we find when we buy or build computers to carry out such attacks. The differences lie in assumptions made in the theoretical estimates, which are not fully spelled out by the authors, and in scaling up hypothesized small machines to ever larger ones without accounting for physical realities. The factors not accounted for are: o R&D costs for the first machine, typically on the order of $10 million. o As more and more chips are added to a machine, two effects occur: o Interconnections increase and increase running time; o Heat from the chips eventually limit [sic] the size of a machine. o Memory costs are not included. o When get [sic] to the very fast processing speed estimates, machines can become Input/Output bound; so [sic] it cannot achieve the estimated speed. o Assuming every algorithm can be tested in same amount of time and key length is the only difference. Table 1 are [sic] the average time estimates made for a given cost done by Michael Wiener of Bell Norther Research in 1995. These are published in Bruce Schneier's Applied Cryptography book. Note that these are average times, one-half of the total exhaust time. Table 2 are [sic] the estimates for total exhaust times using Field Programmmable Gate Arrays (FPGA) and Application Specific ICs (ASICs) done for the Business Software Alliance by Blaze, Diffie, Rivest, Schneier, Shimomura, Thompson, and Wiener in 1996. In addition to the above factors not accounted for they have assumed ASICs cost as low as $10. We find ASICs more typically cost $1000 and their capabilities can vary considerably depending upon the specific task. Table 3 are out estimates based on our experience with a Cray T3D supercomputer with 1024 nodes. This machine costs $30 million. [Tables 1, 2, and 3 not transcribed here.]
The "Edupage Editors" make a critical mistake of logic in an item in RISKS-18.25. The item reports on Philip Zimmermann's testimony before the Senate. In his testimony, Zimmermann discussed a well-known Michael Wiener paper on the feasibility of building a DES cracking machine. The RISKS item correctly states that a $100 million version of the machine could (according to Wiener) crack a DES key in about two minutes. Wiener's hypothetical machine is composed of a parallel array of custom designed DES cracking chips. It is by no means a general purpose computer. Still, the RISKS item says, "Zimmermann's testimony contradicted a recent statement by U.S. Attorney General Janet Reno that even with a 'top of the line supercomputer, decoding a 56-bit key would take over a year and the evidence would be long gone.'" There is no contradiction at all. One is a "machine" that may not even qualify as a programmable computer. A "top of the line supercomputer" should not be expected to be anywhere near as effective a DES cracking engine as would be a machine such as Wiener's, built for the task out of custom chips.
I love how politicians can find ways to say what they want people to believe - actually both are right. It *would* take a supercomputer a year. However as long time readers know neither I nor Michael have been suggesting supercomputers, instead boolean sieves (could use DSPs) made up of cascadable arrays of single bit processors were what I would use. Similar to parallel processors but much simpler hence faster. The state of the art today is about 300 million keys per second for a single sieve. Of course for a few more dollars you can set up a parallel array of sieves, as many as you wish (initial value can be distributed and once cranking you need not be concerned about intercommunication, a single bit would do for success). Actually, the hard part is testing for success - of course if you have known plaintext as most cryptographers always assume...(can think of several ways to avoid that). Other problem is that you also must know the exact algorithm being used - DES of course is fixed (FIPS PUB 46(A|B|C)) but a DES machine would not work - you would need a different one - for COAST. Not difficult, just different. Of course if you knew the target were using ENTRUST... Now I am just am amateur cryptographer just as I have not done any serious digital design for years, still have a pretty good idea what sub-micron lithography is capable of so know the numbers above are supportable. I do disagree with the designated heros of the MIT 7 on one point, they got the economics wrong - while their per-wafer price is possible, the total design would cost a bit more and there would be overhead involved (maybe governments do not worry about that but I do). My current feeling is that 56-bit DES is OK today for a corporation so long as every message is encrypted (including the trivial ones), each key is only used once, and a good random key generator is used. Know that relying on high volume to raise cost-to-break vs value-of-break above buying an employee is "Security by Obscurity" but is real cost/benefit. More (64 bits) is better and many of today's computers have granularities of 32 or 64 bits (something I never see mentioned - design steps beyond 64 are 96 and then 128). Padgett P.S. I was confining my thoughts to symmetric message keys - asymmetric keys and algorithms that may be used for key exchange are an entirely different subject. (Have seen the two confused. Often.).
My local grocery store recently installed a kiosk with the newest generation of automatic teller machine from Wells Fargo Bank. This ATM has a high resolution color graphic display, with a touchscreen and virtual keypad for entering the PIN number. I was standing in line about 6 feet behind the person currently using it when I noticed that each time they entered a digit on the keypad, that digit and only that digit lit up, so I could clearly make out each digit of their PIN as they pressed it, as could anybody walking by. Somehow I think this negates the value of using a PIN, when anybody within a 10 foot radius can read it without even meaning to. Carl Resnikoff WebLogic, Inc
Addison-Wesley, ISBN 0-201-42787-7 http://www.eng.warwick.ac.uk/~neil/safebook.htm This is an introductory text covering all aspects of the development of Safety-Critical Computer Systems. It is intended for undergraduate and postgraduate students, and for engineers who use microcomputers within real-time embedded systems. It assumes no prior knowledge of safety, or of any specific computer hardware or programming language. The book covers all phases of the life of a safety-critical system from its conception and specification, through to its certification, installation, service and decommissioning. It provides information on how to assess the safety implications of projects, and determine the measures necessary to develop systems to meet safety needs. It gives a thorough grounding in the techniques available to investigate the safety aspects of computer-based systems and the methods that may be used to enhance their dependability. The book uses cases studies and worked examples from a wide range of industrial sectors including the nuclear, aircraft, automotive and consumer products industries. The approach taken in equally suited to engineers who consider computers from a hardware, software or systems viewpoint.
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