December 2003 - cypherpunks-legacy

Re: Graphic encryption
by danisch＠ira.uka.de 17 Dec '03

17 Dec '03

> I am currently working for a company that has a graphic encryption > product called PrivaSoft. I was wondering if there were other products > or engines that also provide graphic encryption. (graphic encryption is > the use of a encryption algorythm to scramble an image taken of a > document.) Is there anything particular in graphic encryption? I usually encrypt graphics and document images as regular files with regular encryption... Hadmut

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Re: subjective names and MITM
by jbaber＠mi.leeds.ac.uk 17 Dec '03

17 Dec '03

This discussion can be divided into two separate situations. The first of which is exemplified perfectly by Hal: hfinney(a)shell.portal.com writes: >m5(a)dev.tivoli.com (Mike McNally) writes: > >hfinney(a)shell.portal.com writes: > > > This situation with the MITM is actually about the same as if you were > > > communicating insecurely in the first place. You are exposed to all of > > > the same risks. > >The only way to achieve the level of security offered by physical face > >to face communication with a person is to have a physical face to face > >conversation at some point. If you only ever communicate via > >electronic means, you are always subject to the risk of dealing with a > >synthetic entity. (I think.) >I don't think so, or at least the risk can be minimized much more than in >the model where we just say that we're communicating with keys, therefore >a MITM is perfectly legitimate because it's just a matter of who holds >the keys. Suppose I want to talk to PC Magazine columnist John Dvorak. >Suppose I find a VeriSign certificate for his key, with his name and >employment information. I've never met him. We've never had a face to >face conversation. Yet I claim I can communicate with considerable >security with Dvorak using this certificate, certainly more than if I >just use any old key which is lying around with his name on it, one which >may be owned by a MITM. Here the wish is to communicate with a 'real' person. A person that actually exists and has an in-built reputation that is separate from his key. This is very much a real life situation and is very similar to the first time that you meet someone - it is very hard to know that someone is who they say that they are, few people ask for ID and even ID is possible to fake (an old key that is actually owned by a MITM). In this case the person is known (of) and not the key - therefore it makes sense to attempt to ensure that the link between the key and the person is a strong (trustworthy) as possible. However this is not the case in the second situation: I could say that know that I enjoy reading mail from some people on the list, that I agree with some people on the list or that some people on the list hold very strong opinions on certain subjects. However this would not be correct as I have not met anyone else on the list in person (we do not all live in the US). It would be more correct to say that I enjoy reading mail from some addresses on the list (etc.) - I have no real idea whether hfinney(a)shell.portal.com is Hal or actually Tim expressing different views. If I mail Hal therefore I am actually mailing the entity that sends mail to the list from that address and I would do so being pretty sure that I was communicating with the person who mails here - but I would have no idea whether he is actually male, female, blond, brunette etc apart from what I chose to believe from others. Now mail is far easier to fake/intercept than a digital signature/encryption - at least I hope so. Therefore if Hal where to sign all of his messages I could check the signatures with a public key obtained from anywhere at all and if they passed then I could be confident that the messages were all written by the entity with control of the secret part of the key - at least far more confident than I am at all of the mail from hfinney(a)shell.portal.com actually comes from there. So instead of me getting the idea that hfinney(a)shell.portal.com posts interesting messages I get the idea that the holder of the secret key posts interesting messages - I would probably still use the mail address as keys are less convenient with current mail readers but that is an implementation problem. Hals reputation is therefore transfered to they key - no matter where I got the key from. So if I send encrypted mail to the person with the private part of Hal's key I can be sure that it can only be read by the person who actually sent the messages pertaining to be from Hal. So the MITM problem is 'defined away' in the case where a reputation grows with a key but is still a major problem where you want to transfer a ready made reputation to a key (as in the first example). In effect the key becomes a pseudonym and you can be sure of communicating with the pseudonym safely but can not be sure of anything about the pseudonum that you have not experienced yourself without trusting someone else (VeriSign in the first example). Thus the problem is more reputation transfer than anything else. Jon C. Baber jbaber(a)mi.leeds.ac.uk http://www.chem.surrey.ac.uk:80/~ch02jb/

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Re: Graphic encryption
by shamrock＠netcom.com 17 Dec '03

17 Dec '03

-----BEGIN PGP SIGNED MESSAGE----- In article <199510061517.IAA10725(a)ix5.ix.netcom.com>, privsoft(a)ix.netcom.com (Steve ) wrote: > I am currently working for a company that has a graphic encryption > product called PrivaSoft. I was wondering if there were other products > or engines that also provide graphic encryption. (graphic encryption is > the use of a encryption algorythm to scramble an image taken of a > document.) > > Also if any of ya'll are famillar with graphic encryption, I am looking > for opinions as to its strengths / weaknesses. The description you give us is meaningless. The strengh of an encryption alogirithm must depend only on the algorithim and key used, not on the data (in your case graphics) being encrypted. It is utterly irrelevant _what_ is being encrypted, all that matters is _how_ it is being encrypted. Send us the algorithm and source code and we'll take a look at it. And by the way, "proprietary" algorithms are generally junk and should not be relied upon by security concious individuals and businesses. Only algorithms that have undergone extensive peer review should be considered for use. - --- [This message has been signed by an auto-signing service. A valid signature means only that it has been received at the address corresponding to the signature and forwarded.] -----BEGIN PGP SIGNATURE----- Version: 2.6.2 Comment: Gratis auto-signing service iQBFAwUBMHVT7yoZzwIn1bdtAQEUOgGAnyOPIjo4D18AUDNDzXAcqRLXO7vcaRiw ode3TBA5gLm1FaGPSEk5y5g3VKiVS6ai =bV6Z -----END PGP SIGNATURE-----

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National Secuirty Science and Technology Strategy
by nobody＠REPLAY.COM 17 Dec '03

17 Dec '03

This excerpt is from the summary of a long policy statement on the National Security Science and Technology Strategy published by the White House on September 19. The full report is well worth reading -- it addresses military, economic, intelligence, scientific and technological issues and lays out projected initiatives. Has anyone seen news reports on this? ----- >From URL: http://www.whitehouse.gov/White_House/EOP/OSTP/ nssts/html/execsum-plain.html Executive Summary _______________________________________________________ In March 1995, President Clinton ordered a sweeping reexamination of the United States Government's approach to putting science and technology to the service of national security and global stability in light of the changed security environment, increasing global economic competition, and growing budgetary pressures. This National Security Science and Technology Strategy, the product of that reexamination, is the country's first comprehensive Presidential statement of national security science and technology priorities. It augments the President's National Security Strategy of Engagement and Enlargement by articulating science and technology policies and initiatives that support the President's three primary national security objectives: enhancing our military readiness and capabilities, preventing conflict from occurring through engagement with other nations, and promoting prosperity at home. It advances that document's central approach of preventing conflict and maintaining the capability to respond should conflict occur. It is built on the recognition that our security depends on economic strength as well as military power. And it is grounded in the conviction that investment in science and technology is central to our ability to meet the challenges ahead. This National Security Science and Technology Strategy defines our new approaches to applying science and technology to the challenges that most directly affect our nation's security. [snip balance of summary]

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Re: Graphic encryption
by Rev. Mark Grant 17 Dec '03

17 Dec '03

On Fri, 6 Oct 1995, Lucky Green wrote: >And by the way, "proprietary" algorithms are generally junk and should not >be relied upon by security concious individuals and businesses. Only >algorithms that have undergone extensive peer review should be considered >for use. It's OK, when these guys were spamming Usenet a few weeks ago with their product announcement (admittedly, they did at least keep it to comp groups) they said it was export-approved. Therefore, it can be pretty much written off from a security standpoint - it's at best as good as 40-bit RC4, and I sure wouldn't use that for secure communications. I'd still like to know how it works so we can see just how insecure it is, though. Mark

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Open Market, Inc. Announcing security products
by Harry S. Hawk 17 Dec '03

17 Dec '03

Open Market, Inc. Is announcing "free software and services that will help hundreds of Internet-based businesses and millions of users protect themselves from potential security breaches." I don't know any more info.. I'll send more when available. -- Harry Hawk Manager of Computer Services Warwick Baker & Fiore 212 941 4438 habs(a)warwick.com

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Open Market (more info)
by Harry S. Hawk 17 Dec '03

17 Dec '03

Basically they are going to set up a web site to act as a clearing house for security related breaches. On particular thing they will do is: 1) Hosting a web site where a user with any broswer can find out if their browser is secure. List security problems associated with that browser. "basically a self diagnostic center" That will be done by tues. -- Harry Hawk

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Re: subjective names and MITM
by patrick＠Verity.COM 17 Dec '03

17 Dec '03

> > A public key *is* "very probably unique". A "randomly selected" 1024 bit > prime number has a specific amount of entropy in it. The likelihood of > two users world wide "randomly" choosing the same such prime may be > precisely determined (assuming you can figure the entropy). > Given the difficulty of finding primes, how likely do you think it is that given one of the well known methods and finding the first 1024 bit prime that pops out would give you an effective attack? Patrick _______________________________________________________________________ / These opinions are mine, and not Verity's (except by coincidence;). \ | (\ | | Patrick J. Horgan Verity Inc. \\ Have | | patrick(a)verity.com 1550 Plymouth Street \\ _ Sword | | Phone : (415)960-7600 Mountain View \\/ Will | | FAX : (415)960-7750 California 94303 _/\\ Travel | \___________________________________________________________\)__________/

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Re: Graphic encryption
by Andrew Loewenstern 17 Dec '03

17 Dec '03

> Is there anything particular in graphic encryption? I usually > encrypt graphics and document images as regular files with regular > encryption... I believe graphic encryption outputs a valid image file that is apparently white noise until you perform the decryption transformation on it. An obvious way to do this with a non-lossy file format is to encrypt pixel vales with a stream cipher. Another way to make the image unviewable would be to shuffle the pixels or rasters with a PRNG. andrew

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Open Market, Inc. Announcing security products
by Harry S. Hawk 17 Dec '03

17 Dec '03

Here is what they are going to do.. by tues 1) Hosting a web site where a user with any browser can find out if their browser is secure. List security problems associated with that browser. "a self diagnostic center" Using their knowledge base about browsers to create this feature. shortly thereafter: 2) Creating ref. implementations for the Open Market server; methods of verifying what browser you are connecting with and lookup security bugs and or proceed with transaction. Make CGI scripts available for operators of other servers. Basically letting other sites do what they are doing it step 1. 3) Offer a free upgrade problem for people who have a server that has had a security breach. They can download a known secure server. This upgrade is for any commercial server browser that has a known breach. E.g., update a netsite server but not a CERN 3.0 server even if the CERN operator has hacked it to make it secure. WWW.openmarket.com

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