On Tue, Sep 27, 2016 at 8:06 AM, Georgi Guninski
   <[1]guninski@guninski.com> wrote:

     On Tue, Sep 27, 2016 at 02:43:48PM +0000, Sean Lynch wrote:
     > > Is this a bug at all?
     > >
     >
     > I think the bug is that openssl is silently ignoring parameters,
     because
     > I'm pretty sure what you're doing is producing and verifying sha1
     hashes,
     > not cryptographic signatures. Which means your keys aren't
     entering the
     > picture at all.
     > I
     >
     No, this is not the case. openssl do the math. I verified both
     signatures in my sage implementation and in python's Crypto.DSA, so
     math
     is going on, not only hashes.
     This fails in the same directory with a random new key:
     $ openssl dsaparam 1024 > dsapar ; openssl gendsa dsapar >
     keyrandom.priv ; openssl dsa -in keyrandom.priv -pubout -out
     keyrandom.pub
     $ openssl dgst -sha1 -verify keyrandom.pub -signature file.txt.sig
     file.txt
     Verification Failure

   My apologies. I was on my phone so didn't have ready access to the dgst
   manpage. That does seem very strange.

References

   1. mailto:guninski@guninski.com