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Jake's Blog
Personal blog · jcraige.comprogrammingsecurity
Jake's Blog is a personal blog at jcraige.com about programming and security. Since 2020, 5 different Hacker News readers have linked it 5 times, most often “An Explainer on Ed25519 Clamping”. The last post was in 2020, but the archive is still widely read.
Too few sampled comments (2) to say how often HN recommends it.?
Why HN links it
HN commenters link posts on Curve25519 and ed25519, including an Erlang Curve25519 tour and the dangers of ed25519 SSH keys. The comments discuss prefix searches and why key clamping is needed.
Summarised by Claude from a sample of 2 HN comments that link here. Each comment is marked recommending, critical or neutral (citing without judging); how this works.
Most-linked posts?
- An Explainer on Ed25519 Clamping5 people · 5 mentions · first linked 2020-07-22
What Hacker News says?
I would certainly start by trying to generate all possible 2-byte prefixes, 3-byte prefixes, etc. OK great, I did try that to get some insight as to whether various 2/3/4-byte series at different index positions would show up... and they did. The relative lack of results by adding that 5th byte had me concerned, but figured it's due to the exponentially-decreasing odds. I'll have to read more on what you mean by #2/…
Comment linking /an-explainer-on-ed25519-clamping
on “A Tour of Curve25519 in Erlang [pdf]”Submitted An Explainer on Ed25519 Clamping as a story · 2 points
HN discussionThis article [0] has a good explanation of why clamping is necessary. But the process is very simple, you just generate 32 random bytes, clear the three least significant bits to avoid small-subgroup attacks, then clear the most significant bit and set the second most significant to avoid side-channel attacks which may occur if an implementation isn’t constant-time. The Libsodium source shows this pretty clearly: [1…
Comment linking /an-explainer-on-ed25519-clamping
on “Dangerous toys: Anything to ed25519 (SSH Keys)”Submitted An Explainer on Ed25519 Clamping as a story · 1 points
HN discussionSubmitted An Explainer on Ed25519 Clamping as a story · 1 points
HN discussion