Software engineer at @anthropicai interested in cryptography, security, privacy, and machine learning.

San Francisco
Joined July 2007
so they were private keys all along
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Steve Weis retweeted
Nathan: Do you see why this is funny? Elizabeth: Because all these certificates have to be revoked? Nathan: Yes. But do you understand why 4 is a terrible secret key? Elizabeth: Well... it's equally likely as any other value drawn from the uniform distribution.
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“Can You Slop Out High-Assurance Cryptography?” by Michael Rosenberg: mrosenberg.pub/blog/cryptosl…
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Steve Weis retweeted
*nods sagely* Capricorn moon... just as I expected.....
P-256 was born Friday, August 15th, 1997 at 9:52PM Fort Meade time.
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This P-256 Birthday in mid-August made me crave chocolate-covered strawberries and gave me a hunch. Look who spoke at Crypto’97 within a week of P-256 being generated: iacr.org/conferences/c97/c97…
P-256 was born Friday, August 15th, 1997 at 9:52PM Fort Meade time.
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Working late in Fort Meade before flying out to Santa Barbara on the weekend?
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plot twist the nsa didn't backdoor p-256 they backdoored time itself
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Claude and @avhwl also found that Skipjack cipher's s-box is generated by srand48(48571) plus some swaps.
Replying to @sweis
Claude also noticed that the Skipjack cipher's s-box (F-table?) is generated by srand48(48571) plus some swaps. it could tell by the bits and the way it is. @dadrian update?
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we filed the first complete, machine-verified differential construction for 39 round SHA-256 applying a new technique to ePrint 2026/1120 allowing to take it further than the paper did. just 0.14 bits below current best generic search submission under the same hashsmash cost model. @cyberaxe join forces?
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I spent a good amount of time digging. I found ex-NSA employees, older cryptographers, and old documents. I had four independent people give the "Jerry and Bob deserve a raise" story -- including Jerry Solinas. Turns out nobody was right! saweis.net/posts/nist-curve-…
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As a treat, Claude also reverse engineered the NBS's 1977 DES S-box test vectors and determined that it was generated on a PDP-11 Unix V6 using rand() .
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One year ago, I would have thought replacing an entrenched source-control vendor with homegrown source control and code review systems was a terrible idea. I saw these projects take years before. It was done in 5 months and is supporting 10X the volume. anthropic.com/engineering/re…
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