/// <summary>
/// Sends one or more file descriptors over the given socket with SCM_RIGHTS.
/// </summary>
/// <param name="sock">The socket handle to use.</param>
/// <param name="fds">The file descriptors to send. Must contain at least one.</param>
/// <param name="buffer">The data to send with the message, cannot be null or empty.</param>
public static void send_fds(int sock, int[] fds, byte[] buffer)
{
if (fds == null || fds.Length == 0)
{
throw new ArgumentException("At least one file descriptor must be sent");
}
if (buffer == null || buffer.Length == 0)
{
throw new ArgumentException("The buffer cannot be empty");
}
// Create the SCM_RIGHTS control message
var cmsgbuffer = new byte[Mono.Unix.Native.Syscall.CMSG_SPACE((ulong)fds.Length * sizeof(int))];
var cmsghdr = new Mono.Unix.Native.Cmsghdr
{
cmsg_len = (long)Mono.Unix.Native.Syscall.CMSG_LEN((ulong)fds.Length * sizeof(int)),
cmsg_level = Mono.Unix.Native.UnixSocketProtocol.SOL_SOCKET,
cmsg_type = Mono.Unix.Native.UnixSocketControlMessage.SCM_RIGHTS,
};
// Create the message header
var msghdr = new Mono.Unix.Native.Msghdr
{
msg_control = cmsgbuffer,
msg_controllen = cmsgbuffer.Length,
};
cmsghdr.WriteToBuffer(msghdr, 0);
// Copy in the file handles
var dataOffset = Mono.Unix.Native.Syscall.CMSG_DATA(msghdr, 0);
for (var i = 0; i < fds.Length; i++)
{
Array.Copy(BitConverter.GetBytes(fds[i]), 0, msghdr.msg_control, dataOffset, sizeof(int));
dataOffset += sizeof(int);
}
// Pin the buffer we are sending
using (var ptr_buffer1 = new GuardedHandle(buffer))
{
// Put the buffer into the IO vector attached to the message
var iovecs = new[] {
new Mono.Unix.Native.Iovec {
iov_base = ptr_buffer1.Address,
iov_len = (ulong)buffer.Length,
},
};
msghdr.msg_iov = iovecs;
msghdr.msg_iovlen = 1;
// Send it
var ret = Mono.Unix.Native.Syscall.sendmsg(sock, msghdr, 0);
if (ret < 0)
{
Mono.Unix.UnixMarshal.ThrowExceptionForLastError();
}
}
}
/// <summary>
/// Reads file descriptors and the message from a SCM_RIGHTS message
/// </summary>
/// <returns>The file descriptors and the bytes.</returns>
/// <param name="handle">The socket to read from.</param>
public static async Task <List <Tuple <int[], byte[]> > > recv_fds_async(MonitoredHandle handle)
{
var buffer = new byte[1024];
var cmsg = new byte[1024];
var msghdr = new Mono.Unix.Native.Msghdr
{
msg_control = cmsg,
msg_controllen = cmsg.Length,
};
long datalen;
await handle.WaitForReadAsync;
var res = new List <Tuple <int[], byte[]> >();
using (var ptr_buffer = new GuardedHandle(buffer))
{
var iovec = new [] {
new Mono.Unix.Native.Iovec {
iov_base = ptr_buffer.Address,
iov_len = (ulong)buffer.Length,
},
};
msghdr.msg_iov = iovec;
msghdr.msg_iovlen = 1;
DebugHelper.WriteLine("Calling recvmsg");
while ((datalen = Mono.Unix.Native.Syscall.recvmsg(handle.Handle, msghdr, 0)) != -1)
{
DebugHelper.WriteLine("Called recvmsg: {0}", datalen);
if (datalen == 0)
{
DebugHelper.WriteLine("No more data, stopping recv_fds");
handle.Dispose();
break;
}
if (datalen < 0)
{
Mono.Unix.UnixMarshal.ThrowExceptionForLastError();
}
// Get the offset of the first message
var offset = Mono.Unix.Native.Syscall.CMSG_FIRSTHDR(msghdr);
DebugHelper.WriteLine("Called recvmsg, offset: {0}", offset);
// Extract the bytes
var recvHdr = Mono.Unix.Native.Cmsghdr.ReadFromBuffer(msghdr, offset);
//DebugHelper.WriteLine("Buffer has, recvHdr.cmsg_len: {0}", recvHdr.cmsg_len);
var data = new byte[datalen];
Array.Copy(buffer, data, data.Length);
//DebugHelper.WriteLine("Got {0} bytes of data", data.Length);
//foreach (var n in data)
// Console.Write("{0}, ", n);
//DebugHelper.WriteLine();
// See how many bytes are of file descriptors we have
var recvDataOffset = Mono.Unix.Native.Syscall.CMSG_DATA(msghdr, offset);
//var userData = recvHdr.cmsg_len - (int)Mono.Unix.Native.Syscall.CMSG_LEN(0);
var bytes = recvHdr.cmsg_len - (recvDataOffset - offset);
var fdCount = bytes / sizeof(int);
var fds = new int[fdCount];
//DebugHelper.WriteLine("Got {0} fds ({1} bytes)", fdCount, bytes);
// Extract the file descriptors
for (int i = 0; i < fdCount; i++)
{
fds[i] = BitConverter.ToInt32(msghdr.msg_control, (int)(recvDataOffset + (sizeof(int) * i)));
//DebugHelper.WriteLine($"fd[{i}] = {fds[i]}");
}
//DebugHelper.WriteLine("Read {0} fds and {1} bytes", fds.Length, data.Length);
// Check that we only have a single message
offset = Mono.Unix.Native.Syscall.CMSG_NXTHDR(msghdr, offset);
if (offset != -1)
{
System.Diagnostics.Trace.WriteLine("WARNING: more than one message detected when reading SCM_RIGHTS, only processing the first one");
}
res.Add(new Tuple <int[], byte[]>(fds, data));
}
}
var lasterr = Mono.Unix.Native.Stdlib.GetLastError();
if (res.Count == 0 && datalen < 0 && lasterr != Mono.Unix.Native.Errno.EAGAIN && lasterr != Mono.Unix.Native.Errno.EWOULDBLOCK)
{
throw new System.IO.IOException($"Unexpected error code while reading socket: {lasterr}");
}
return(res);
}
public ReceivedMessage RecvMsg ()
{
// int r = 0;
//
// do {
// r = (int)recvmsg (Handle, bufP, flags);
// } while (r < 0 && UnixError.ShouldRetry);
//
// if (r < 0)
// throw UnixError.GetLastUnixException ();
//
// return r;
var buffer2 = new byte[1024*10];
var cmsg2 = new byte[1024*10];
var msghdr2 = new Mono.Unix.Native.Msghdr {
msg_control = cmsg2,
msg_controllen = cmsg2.Length,
};
var result = new ReceivedMessage ();
fixed (byte* ptr_buffer2 = buffer2) {
var iovecs2 = new Mono.Unix.Native.Iovec[] {
new Mono.Unix.Native.Iovec {
iov_base = (IntPtr) ptr_buffer2,
iov_len = (ulong) buffer2.Length,
},
};
msghdr2.msg_iov = iovecs2;
msghdr2.msg_iovlen = 1;
//System.Console.WriteLine ("recvmsg");
var ret = Mono.Unix.Native.Syscall.recvmsg (Handle, msghdr2,0);
if (ret ==-1) {
var lastError = Marshal.GetLastWin32Error ();
System.Console.WriteLine ("Last error " + lastError);
System.Console.WriteLine ("Description" + Mono.Unix.UnixMarshal.GetErrorDescription((Mono.Unix.Native.Errno)lastError));
Mono.Unix.UnixMarshal.ThrowExceptionForLastError ();
}
result.Read = ret;
result.Message = buffer2;
}
#if UNIXFDS
var fds = new global::System.Collections.Generic.List<int> ();
for (long offset = Mono.Unix.Native.Syscall.CMSG_FIRSTHDR (msghdr2); offset != -1; offset = Mono.Unix.Native.Syscall.CMSG_NXTHDR (msghdr2, offset)) {
var recvHdr = Mono.Unix.Native.Cmsghdr.ReadFromBuffer (msghdr2, offset);
var recvDataOffset = Mono.Unix.Native.Syscall.CMSG_DATA (msghdr2, offset);
var bytes = recvHdr.cmsg_len - (recvDataOffset - offset);
//Assert.AreEqual (bytes % sizeof (int), 0);
var fdCount = bytes / sizeof (int);
//System.Console.WriteLine("based on struct size, there should be "+fdCount+" fds");
fixed (byte* ptr = msghdr2.msg_control)
for (int i = 0; i < fdCount; i++)
fds.Add (((int*) (ptr + recvDataOffset))[i]);
}
if(fds.Count>0)
{
result.FileDescriptors = fds.ToArray ();
}
#endif
return result;
}
/// <summary>
/// Reads file descriptors and the message from a SCM_RIGHTS message
/// </summary>
/// <returns>The file descriptors and the bytes.</returns>
/// <param name="sock">The socket to read from.</param>
public static Tuple <int[], byte[]> recv_fds(int sock)
{
var buffer = new byte[1024];
var cmsg = new byte[1024];
var msghdr = new Mono.Unix.Native.Msghdr
{
msg_control = cmsg,
msg_controllen = cmsg.Length,
};
long datalen;
using (var ptr_buffer = new GuardedHandle(buffer))
{
var iovec = new[] {
new Mono.Unix.Native.Iovec {
iov_base = ptr_buffer.Address,
iov_len = (ulong)buffer.Length,
},
};
msghdr.msg_iov = iovec;
msghdr.msg_iovlen = 1;
DebugHelper.WriteLine("{0}: Calling recvmsg", System.Diagnostics.Process.GetCurrentProcess().Id);
datalen = Mono.Unix.Native.Syscall.recvmsg(sock, msghdr, 0);
DebugHelper.WriteLine("{0}: Called recvmsg: {1}", System.Diagnostics.Process.GetCurrentProcess().Id, datalen);
if (datalen == 0)
{
return(null);
}
if (datalen < 0)
{
Mono.Unix.UnixMarshal.ThrowExceptionForLastError();
}
}
// Get the offset of the first message
var offset = Mono.Unix.Native.Syscall.CMSG_FIRSTHDR(msghdr);
DebugHelper.WriteLine("{0}: Called recvmsg, offset: {1}", System.Diagnostics.Process.GetCurrentProcess().Id, offset);
// Extract the bytes
var recvHdr = Mono.Unix.Native.Cmsghdr.ReadFromBuffer(msghdr, offset);
//DebugHelper.WriteLine("Buffer has, recvHdr.cmsg_len: {0}", recvHdr.cmsg_len);
var data = new byte[datalen];
Array.Copy(buffer, data, data.Length);
//DebugHelper.WriteLine("Got {0} bytes of data", data.Length);
//foreach (var n in data)
// Console.Write("{0}, ", n);
//DebugHelper.WriteLine();
// See how many bytes are of file descriptors we have
var recvDataOffset = Mono.Unix.Native.Syscall.CMSG_DATA(msghdr, offset);
//var userData = recvHdr.cmsg_len - (int)Mono.Unix.Native.Syscall.CMSG_LEN(0);
var bytes = recvHdr.cmsg_len - (recvDataOffset - offset);
var fdCount = bytes / sizeof(int);
var fds = new int[fdCount];
//DebugHelper.WriteLine("Got {0} fds ({1} bytes)", fdCount, bytes);
// Extract the file descriptors
for (int i = 0; i < fdCount; i++)
{
fds[i] = BitConverter.ToInt32(msghdr.msg_control, (int)(recvDataOffset + (sizeof(int) * i)));
//DebugHelper.WriteLine($"fd[{i}] = {fds[i]}");
}
//DebugHelper.WriteLine("Read {0} fds and {1} bytes", fds.Length, data.Length);
// Check that we only have a single message
offset = Mono.Unix.Native.Syscall.CMSG_NXTHDR(msghdr, offset);
if (offset != -1)
{
System.Diagnostics.Trace.WriteLine("WARNING: more than one message detected when reading SCM_RIGHTS, only processing the first one");
}
return(new Tuple <int[], byte[]>(fds, data));
}
public ReceivedMessage RecvMsg()
{
// int r = 0;
//
// do {
// r = (int)recvmsg (Handle, bufP, flags);
// } while (r < 0 && UnixError.ShouldRetry);
//
// if (r < 0)
// throw UnixError.GetLastUnixException ();
//
// return r;
var buffer2 = new byte[1024 * 10];
var cmsg2 = new byte[1024 * 10];
var msghdr2 = new Mono.Unix.Native.Msghdr {
msg_control = cmsg2,
msg_controllen = cmsg2.Length,
};
var result = new ReceivedMessage();
fixed(byte *ptr_buffer2 = buffer2)
{
var iovecs2 = new Mono.Unix.Native.Iovec[] {
new Mono.Unix.Native.Iovec {
iov_base = (IntPtr)ptr_buffer2,
iov_len = (ulong)buffer2.Length,
},
};
msghdr2.msg_iov = iovecs2;
msghdr2.msg_iovlen = 1;
//System.Console.WriteLine ("recvmsg");
var ret = Mono.Unix.Native.Syscall.recvmsg(Handle, msghdr2, 0);
if (ret == -1)
{
var lastError = Marshal.GetLastWin32Error();
System.Console.WriteLine("Last error " + lastError);
System.Console.WriteLine("Description" + Mono.Unix.UnixMarshal.GetErrorDescription((Mono.Unix.Native.Errno)lastError));
Mono.Unix.UnixMarshal.ThrowExceptionForLastError();
}
result.Read = ret;
result.Message = buffer2;
}
#if UNIXFDS
var fds = new global::System.Collections.Generic.List <int> ();
for (long offset = Mono.Unix.Native.Syscall.CMSG_FIRSTHDR(msghdr2); offset != -1; offset = Mono.Unix.Native.Syscall.CMSG_NXTHDR(msghdr2, offset))
{
var recvHdr = Mono.Unix.Native.Cmsghdr.ReadFromBuffer(msghdr2, offset);
var recvDataOffset = Mono.Unix.Native.Syscall.CMSG_DATA(msghdr2, offset);
var bytes = recvHdr.cmsg_len - (recvDataOffset - offset);
//Assert.AreEqual (bytes % sizeof (int), 0);
var fdCount = bytes / sizeof(int);
//System.Console.WriteLine("based on struct size, there should be "+fdCount+" fds");
fixed(byte *ptr = msghdr2.msg_control)
for (int i = 0; i < fdCount; i++)
{
fds.Add(((int *)(ptr + recvDataOffset))[i]);
}
}
if (fds.Count > 0)
{
result.FileDescriptors = fds.ToArray();
}
#endif
return(result);
}
