public static WebSocketFrame Unpack(byte *s, int len)
{
if (s == null || len < HEADERSIZE)
{
return(default(WebSocketFrame));
}
WebSocketFrame frame = new WebSocketFrame();
frame.fin = ((*s >> 7) & 0x01) == 1;
frame.rsv1 = ((*s >> 6) & 0x01) == 1;
frame.rsv2 = ((*s >> 5) & 0x01) == 1;
frame.rsv3 = ((*s >> 4) & 0x01) == 1;
frame.opcode = (byte)(0x0F & *s);
frame.masked = (s[1] >> 7) == 0x01;
frame.payload_length = (s[1] & 0x7F);
s += 2;
len -= 2;
if (frame.payload_length == 0x7E)
{
// If 126, the following 2 bytes interpreted as a 16-bit unsigned integer are the payload length
if (len < HEADERSIZE + 2)
{
return(null);
}
frame.payload_length =
*s++ << 0x08 |
*s++ & 0xFF;
len -= 2;
}
else if (frame.payload_length == 0x7F)
{
// If 127, the following 8 bytes interpreted as a 64-bit unsigned integer (the most significant bit MUST be 0) are the payload length
if (len < HEADERSIZE + 8)
{
return(null);
}
frame.payload_length =
*s++ << 0x38 |
*s++ << 0x30 |
*s++ << 0x28 |
*s++ << 0x20 |
*s++ << 0x18 |
*s++ << 0x10 |
*s++ << 0x08 |
*s++ & 0xFF;
len -= 8;
}
byte[] mask = new byte[4];
if (frame.masked)
{
mask[0] = s[0];
mask[1] = s[1];
mask[2] = s[2];
mask[3] = s[3];
s += 4;
len -= 4;
frame.masking_key = mask;
}
frame.payload_data = new byte[frame.payload_length];
PayloadAdditional(frame, s, len);
return(frame);
}
public static MemoryStream Pack(WebSocketFrame frame)
{
byte[] header = PackFrameHeader(frame);
if (header == null)
{
return(null);
}
MemoryStream ms = new MemoryStream();
ms.Write(header, 0, 2);
int len = (header[1] & 0x7F);
byte[] buffer = null;
if (len == 0x7E)
{
buffer = new byte[2];
fixed(long *pinned = &frame.payload_length)
{
byte *s = (byte *)pinned;
buffer[1] = *s++;
buffer[0] = *s++;
}
}
else if (len == 0x7F)
{
buffer = new byte[8];
fixed(long *pinned = &frame.payload_length)
{
byte *s = (byte *)pinned;
buffer[7] = *s++;
buffer[6] = *s++;
buffer[5] = *s++;
buffer[4] = *s++;
buffer[3] = *s++;
buffer[2] = *s++;
buffer[1] = *s++;
buffer[0] = *s++;
}
}
if (buffer != null)
{
ms.Write(buffer, 0, buffer.Length);
}
byte[] mask = null;
if (frame.masked)
{
Random rand = new Random();
mask = new byte[4];
for (int i = 0; i < 4; i++)
{
mask[i] = (byte)rand.Next(0x00, 0xFF);
}
frame.masking_key = mask;
ms.Write(mask, 0, 4);
}
byte[] payload = frame.payload_data;
if (frame.masked)
{
for (long i = 0; i < frame.payload_length; i++)
{
payload[i] ^= mask[i % 4];
}
}
ms.Write(payload, 0, payload.Length);
return(ms);
}