title: ECDSA signing and verification in windows and linux
body: <p>This is continuation of my previous post (<a href="https://stackoverflow.com/questions/20992760/understanding-bcryptsignhash-output-signature">Understanding BCryptSignHash output signature</a>).</p>
  
  <p>Let me clearly state my problem:</p>
  
  <ol>
  <li>I need to sign a data in windows application level.</li>
  <li>I need to verify the same in linux application level and windows driver (that i have wrote).</li>
  </ol>
  
  <p>I tried following:</p>
  
  <ol>
  <li><p>Using CryptoAPI, i was able to sign in windows application level and verify in the windows driver. In linux, i tried to use simpleECDSA (<a href="http://jonasfj.dk/blog/2007/12/simpleecdsa-a-simple-implementation-of-ecdsa-in-c/" rel="nofollow noreferrer">http://jonasfj.dk/blog/2007/12/simpleecdsa-a-simple-implementation-of-ecdsa-in-c/</a>) to verify the signature (generated using cryptoAPI). I was able to convert the binary key blobs from cryptoAPI in simpleECDSA but could not interpret the signature.</p></li>
  <li><p>Using Crypto++ library, i was able to sign in windows application level and verify in linux application level but could not use the same to verify in windows driver.</p></li>
  </ol>
  
  <p>Kindly let me know if there is a library available or a way that i could use the same public/private key and signature across windows application/driver and linux.</p>
  
  <p>Am new to cryptography hence forgive my naiveness.</p>
  
  <p>Thanks,</p>
  
  <p>F</p>