From 207652246a456ba95a2a421d513e41beb5a74ab5 Mon Sep 17 00:00:00 2001
From: NIIBE Yutaka <gniibe@fsij.org>
Date: Tue, 18 Apr 2017 15:45:25 +0900
Subject: [PATCH] emulation: USB device emulation by USBIP protocol.

---
 emulation/usbip-server.c | 212 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 212 insertions(+)
 create mode 100644 emulation/usbip-server.c

diff --git a/emulation/usbip-server.c b/emulation/usbip-server.c
new file mode 100644
index 0000000..26b0af2
--- /dev/null
+++ b/emulation/usbip-server.c
@@ -0,0 +1,212 @@
+/*                                                    -*- coding: utf-8 -*-
+ * usbip-server.c - USB Device Emulation by USBIP Protocol
+ *
+ * Copyright (C) 2017  Free Software Initiative of Japan
+ * Author: NIIBE Yutaka <gniibe@fsij.org>
+ *
+ * This file is a part of Gnuk, a GnuPG USB Token implementation.
+ *
+ * Gnuk is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Gnuk is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
+ * License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include <unistd.h>
+
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <arpa/inet.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+
+#define USBIP_PORT 3240
+
+#define CMD_REQ_LIST   0x01008005
+#define CMD_REQ_ATTACH 0x01008003
+#define CMD_URB        0x00000001
+#define CMD_DETACH     0x00000002
+
+struct usbip_msg_head {
+  uint32_t cmd;
+  uint32_t seq;
+};
+
+static char *
+list_devices (size_t *len_p)
+{
+  *len_p = 0;
+  return NULL;
+}
+
+static char *
+attach_device (char busid[32], size_t *len_p)
+{
+  *len_p = 0;
+  return NULL;
+}
+
+static int
+handle_urb (int fd)
+{
+  return 0;
+}
+
+
+
+void
+run_server (void)
+{
+  int sock;
+  struct sockaddr_in v4addr;
+  const int one = 1;
+
+  if ((sock = socket (PF_INET, SOCK_STREAM, 0)) < 0)
+    {
+      perror ("socket");
+      exit (1);
+    }
+
+  if (setsockopt (sock, SOL_SOCKET, SO_REUSEADDR,
+		  (const char*)&one, sizeof (int)) < 0)
+    perror ("WARN: setsockopt");
+
+  memset (&v4addr, 0, sizeof (v4addr));
+  v4addr.sin_family = AF_INET;
+  v4addr.sin_addr.s_addr = htonl (INADDR_LOOPBACK);
+  v4addr.sin_port = htons (USBIP_PORT);
+
+  if (bind (sock, (const struct sockaddr *)&v4addr, sizeof (v4addr)) < 0)
+    {
+      perror ("bind");
+      exit (1);
+    }
+
+  /* We only accept a connection from a single client.  */
+  if (listen (sock, 1) < 0)
+    {
+      perror ("listen");
+      exit (1);
+    }
+
+  for (;;)
+    {
+      int fd;
+      int attached = 0;
+
+      /* We don't care who is connecting.  */
+      if ((fd = accept (sock, NULL, NULL)) < 0)
+        {
+          perror ("accept");
+          exit (1);
+        }
+
+      for (;;)
+        {
+	  struct usbip_msg_head msg;
+
+	  if (recv (fd, (char *)&msg, sizeof (msg), 0) != sizeof (msg))
+	    {
+	      perror ("msg recv");
+	      break;
+	    }
+
+	  msg.cmd = ntohl (msg.cmd);
+	  msg.seq = ntohl (msg.seq);
+
+	  if (msg.cmd == CMD_REQ_LIST)
+	    {
+	      char *device_list;
+	      size_t device_list_size;
+
+	      if (attached)
+		{
+		  fprintf (stderr, "REQ list while attached\n");
+		  break;
+		}
+
+	      device_list = list_devices (&device_list_size);
+
+	      if (send (fd, device_list, device_list_size, 0) != device_list_size)
+		{
+		  perror ("list send");
+		  break;
+		}
+
+	      free (device_list);
+	    }
+	  else if (msg.cmd == CMD_REQ_ATTACH)
+	    {
+	      char busid[32];
+	      char *attach;
+	      size_t attach_size;
+
+	      if (attached)
+		{
+		  fprintf (stderr, "REQ attach while attached\n");
+		  break;
+		}
+	      
+	      if (recv (fd, busid, 32, 0) != 32)
+		{
+		  perror ("attach recv");
+		  break;
+		}
+
+	      attach = attach_device (busid, &attach_size);
+	      if (send (fd, attach, attach_size, 0) != attach_size)
+		{
+		  perror ("list send");
+		  break;
+		}
+
+	      free (attach);
+	      attached = 1;
+	    }
+	  else if (msg.cmd == CMD_URB)
+	    {
+	      if (!attached)
+		{
+		  fprintf (stderr, "URB while attached\n");
+		  break;
+		}
+
+	      if (handle_urb (fd) < 0)
+		{
+		  fprintf (stderr, "URB handling failed\n");
+		  break;
+		}
+	    }
+	  else if(msg.cmd == CMD_DETACH)
+	    {
+	      if (!attached)
+		{
+		  fprintf (stderr, "DETACH while attached\n");
+		  break;
+		}
+
+	      /* send reply??? */
+	      break;
+	    }
+	  else
+	    {
+	      fprintf (stderr, "Unknown command %x, disconnecting.\n", msg.cmd);
+	      break;
+	    }
+	}
+
+       close (fd);
+    }
+}