Re: Thermal Imaging Decision Applicable to TEMPEST?

2001-06-12 Thread Sidney Markowitz
John Young wrote: Remote acquisition of electronic emissions, say from outside a home, are not currently prohibited by law as far as I know. And the language of the thermal imaging decision makes it applicable to any technology not commonly in use. IANAL, but when I read the decision it

Senators on civil liberties

2001-09-24 Thread Sidney Markowitz
Here's a quote from the Washington Post last Sunday, 23 Sept, 2001. The URL http://www.washingtonpost.com/wp-dyn/articles/A10701-2001Sep22.html is good for 2 weeks from then: - I've been getting e-mails from all over the country, from people both on the left and the right,

Re: Rijndael in Assembler for x86?

2001-10-14 Thread Sidney Markowitz
A little over a month ago Perry Metzger asked about free assembler language implementations of Rijndael for x86. Helger Lipmaa, whose commercial assembler language version seems to be the fastest, mentioned Brian Gladman as having the best free C implementation. Gladman's web page now says that

Re: First Steganographic Image in the Wild

2001-10-15 Thread Sidney Markowitz
The URL Kevin posted is slashdotted because of this article http://slashdot.org/articles/01/10/15/1727249.shtml Based on the comments on slashdot it appears that Niels Provos, whose program found no steganography in millions of images on the web, was able to detect and decode an example image

Re: (A)RC4 state leakage

2001-12-27 Thread Sidney Markowitz
Here's something by Ron Rivest about RC4 security that will give you a simple overview before delving into the articles that Steve Bellovin cited in his message. Note that Steve Bellovin's link includes the two papers on RC4 weaknesses that Rivest references.

Re: biometrics

2002-01-28 Thread Sidney Markowitz
On Sun, 2002-01-27 at 14:07, [EMAIL PROTECTED] wrote: The issue then is that biometric represents a particularly difficult shared-secret that doesn't have to be memorized Shared secret? People don't leave a copy of their PIN on every water glass they use. -- sidney

Bernstein's fast factorization

2002-02-27 Thread Sidney Markowitz
Someone on another mailing list pointed me to this posting by Dan Bernstein on sci.crypt newsgroup: http://groups.google.com/groups?hl=enselm=2002Jan1608.53.39.5497%40cr.yp.to [begin quote] From: D. J. Bernstein ([EMAIL PROTECTED]) Subject: Re: Strength of PGP vs SSL Newsgroups:

Re: Schneier on Bernstein factoring machine

2002-04-16 Thread Sidney Markowitz
Does anyone else notice the contradiction in these two paragraphs? First Bruce says that businesses can reasonably be content with 1024 bit keys, then he appears shocked that Lucky Green still has a 1024 bit key? The big news is does not mean the same as I'm shocked that. He appears to agree

Re: [aleph1@securityfocus.com] Implementation of Chosen-Ciphertext Attacks against PGP and GnuPG

2002-08-13 Thread Sidney Markowitz
[Perry message forwarded a notice of a paper on an attack against PGP and GnuPG] A posting on bugtraq in response said, in part: From: Werner Koch [EMAIL PROTECTED] [...] Countermeasures are defined in the OpenPGP drafts since October 2000. This MDC (Manipulation Detection Code) feature is

Re: [Bruce Schneier schneier@counterpane.com] CRYPTO-GRAM, October 15, 2002

2002-10-16 Thread Sidney Markowitz
Bill Frantz [EMAIL PROTECTED] asked: Does anyone run a service that will check an IP address for open ports? (I'd like to test my firewall.) A Google search for 'nmap test' came up with this as the first hit: http://www.linux-sec.net/Audit/nmap.test.gwif.html It seems to offer that service,

Re: Why is RMAC resistant to birthday attacks?

2002-10-22 Thread Sidney Markowitz
Ed Gerck [EMAIL PROTECTED] It does to (as you can read in the paper). BTW, the easily applies to the case WITHOUT salt Well, to be really pedantic the paper never says that it is easy only that it has a work factor of the square root of the number of possible MAC strings without salt, and that

Re: Why is RMAC resistant to birthday attacks?

2002-10-22 Thread Sidney Markowitz
[EMAIL PROTECTED] I want to understand the assumptions (threat models) behind the work factor estimates. Does the above look right? I just realized something about the salt in the RMAC algorithm, although it may have been obvious to everyone else: RMAC is equivalent to a HMAC hash-based MAC

Re: Why is RMAC resistant to birthday attacks?

2002-10-22 Thread Sidney Markowitz
Ed Gerck [EMAIL PROTECTED] said: No -- these are all independent things. One can build an RMAC wih SHA-1. An RMAC does not have to use an HMAC scheme. One can also have an HMAC hash-based MAC algorithm using a block cipher, that is not an RMAC. Some quotes from the paper: This paper defines

Re: Why is RMAC resistant to birthday attacks?

2002-10-22 Thread Sidney Markowitz
Ed Gerck [EMAIL PROTECTED] wrote: A minor nit, but sometimes looking into why things were devised is helpful. What I explained can be found in http://csrc.nist.gov/encryption/modes/workshop2/report.pdf Thank you, that was really helpful in seeing the motivation for the work that led to the

Re: comparing RMAC to AES+CBC-MAC or XCBC (Re: Why is RMAC resistant to birthday attacks?)

2002-10-24 Thread Sidney Markowitz
Adam Back [EMAIL PROTECTED] wrote: See for example Rogaway's arguments about limited value of defending against extension forgery attacks in XCBC: [... quote snipped ...] http://csrc.nist.gov/encryption/modes/workshop2/presentations/xcbc.pdf This doesn't contain the paragraph that you quoted,

Re: question about rsa encryption

2003-02-03 Thread Sidney Markowitz
Scott G. Kelly [EMAIL PROTECTED] wrote: I seem to recall reading somewhere that there is some issue with directly encrypting data with an RSA public key, perhaps some vulnerability The short answer is that you should use one of the standard padding modes that are designed for RSA encryption,

Re: question about rsa encryption

2003-02-04 Thread Sidney Markowitz
Ralf Senderek [EMAIL PROTECTED] asked: And if one loves to learn about every single one of them, can you (or others) give some references ? The page titled Prescriptions for Applications that are Vulnerable to the Adaptive Chosen Ciphertext Attack on PKCS #1 v1.5 at URL

Re: AES-128 keys unique for fixed plaintext/ciphertext pair?

2003-02-18 Thread Sidney Markowitz
Ed Gerck [EMAIL PROTECTED] wrote: For each AES-128 plaintext/ciphertext (c,p) pair with length equal to or larger than the unicity distance, there exists exactly one key k such that c=AES-128-Encrypt(p, k). Excuse my naivete in the math for this, but is it relevant that the unicity distance

Re: Face-Recognition Technology Improves

2003-03-14 Thread Sidney Markowitz
at the less busy airports (source Airports Council International, 10 Busiest Airports in US by Number of Passengers, 2001). -- sidney markowitz [EMAIL PROTECTED] - The Cryptography Mailing List Unsubscribe by sending unsubscribe

Re: Face-Recognition Technology Improves

2003-03-16 Thread Sidney Markowitz
Derek Atkins [EMAIL PROTECTED] wrote: Were there really 750 Million Passengers flying through ATL? No, 75 million. If you look at my message again I did correctly say 750,000 for the 1% false positive figure, although I did not type a comma to make it easier to read. Therefore, a better

Re: Run a remailer, go to jail?

2003-03-28 Thread Sidney Markowitz
possession, use, manufacture, etc., would seem to have the same kind of broadness we have seen misused in the DMCA, covering people who sell NAT and encryption tools that might be used by someone who sends email while attempting to defraud a communications service provider. -- sidney markowitz