On Tue, Sep 27, 2016 at 8:06 AM, Georgi Guninski <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.