title: ASN.1 DER formatted private key
body: <p>Why is the modulus padded with leading zeros? I was reading PKCS#1 and PKCS#8 but didn't find anything about it.
  In c# the leading zeros must be removed, does anybody know why?</p>
  
  <p>At <a href="http://etherhack.co.uk/asymmetric/docs/rsa_key_breakdown.html">http://etherhack.co.uk/asymmetric/docs/rsa_key_breakdown.html</a>, you can see that the modulus and exponent have leading zeros. The question is why they have it, I haven't found an explanation anywhere yet.</p>