I am sorry if this is a naive question but is there any justification for the way that s is computed in the DSA signature algorithm:

$$ s = k^{-1} * (rx + m) $$

This looks to me like a very arbitrary combination of $k$, $r$, $x$ and $m$. Is this just one particular way that's found to work or does it actually have some kind of structure/reason behind it that I am missing?

  • 1
    $\begingroup$ I'll vote this up because the Wikipedia page doesn't show the Discrete Logarithm problem. You should however read into it a bit before asking, did you read the paper by Divest, Shamir and Adleman? $\endgroup$
    – Maarten Bodewes
    Mar 24, 2018 at 20:06


Browse other questions tagged or ask your own question.