static byte[] ConvertToP1363Signature(byte[] ASN1Sig)
{
AsnParser asn = new AsnParser(ASN1Sig);
asn.NextSequence();
byte[] r = asn.NextInteger();
byte[] s = asn.NextInteger();
// Returned to caller
byte[] p1363Signature = new byte[40];
if (r.Length > 21 || (r.Length == 21 && r[0] != 0))
{
// WTF???
// Reject - signature verification failed
}
else if (r.Length == 21)
{
// r[0] = 0
// r[1]'s high bit *should* be set
Array.Copy(r, 1, p1363Signature, 0, 20);
}
else if (r.Length == 20)
{
// r[0]'s high bit *should not* be set
Array.Copy(r, 0, p1363Signature, 0, 20);
}
else
{
// fewer than 20 bytes
int len = r.Length;
int off = 20 - len;
Array.Copy(r, 0, p1363Signature, off, len);
}
if (s.Length > 21 || (s.Length == 21 && s[0] != 0))
{
// WTF???
// Reject - signature verification failed
}
else if (s.Length == 21)
{
// s[0] = 0
// s[1]'s high bit *should* be set
Array.Copy(s, 1, p1363Signature, 20, 20);
}
else if (s.Length == 20)
{
// s[0]'s high bit *should not* be set
Array.Copy(s, 0, p1363Signature, 20, 20);
}
else
{
// fewer than 20 bytes
int len = s.Length;
int off = 40 - len;
Array.Copy(s, 0, p1363Signature, off, len);
}
return p1363Signature;
}
internal AsnKeyParser(String pathname)
{
using (BinaryReader reader = new BinaryReader(
new FileStream(pathname, FileMode.Open, FileAccess.Read)))
{
FileInfo info = new FileInfo(pathname);
parser = new AsnParser(reader.ReadBytes((int)info.Length));
}
}
internal AsnKeyParser(byte[] content)
{
parser = new AsnParser(content);
}
