/*
* Send a "normal" message to the peer, of the specified
* length: this is a sequence of 'len' random bytes, distinct
* from 0x0A, followed one 0x0A byte. The peer is supposed to
* respond with the SHA-1 hash of the message bytes (excluding
* the final 0x0A), encoded in hexadecimal (lowercase) and
* followed by a newline (0x0A). An exception is thrown if the
* expected value is not obtained.
*/
void SendMessageNormal(SSLEngine eng, int len)
{
SHA1 sha1 = new SHA1();
byte[] buf = new byte[len + 1];
RNG.GetBytesNonZero(buf, 0, len);
for (int i = 0; i < len; i++)
{
buf[i] ^= 0x0A;
}
buf[len] = 0x0A;
if (len == 1)
{
buf[0] = (byte)('a' + (buf[0] & 0x0F));
}
StringBuilder sb = new StringBuilder();
foreach (byte b in sha1.Hash(buf, 0, len))
{
sb.AppendFormat("{0:x2}", b);
}
sb.Append('\n');
eng.Write(buf, 0, buf.Length);
eng.Flush();
for (int i = 0; i < sb.Length; i++)
{
int x = eng.ReadByte();
int y = sb[i];
if (x != y)
{
throw new Exception(string.Format(
"received {0} (exp: {1})", y, x));
}
}
}
string ReadLine(SSLEngine eng)
{
StringBuilder sb = new StringBuilder();
for (;;)
{
int c = eng.ReadByte();
if (c < 0)
{
throw new Exception("Unexpected EOF");
}
if (c == 0x0A)
{
return(sb.ToString());
}
sb.Append((char)c);
}
}