/*
* TAP-Win32 -- A kernel driver to provide virtual tap device functionality
* on Windows. Originally derived from the CIPE-Win32
* project by Damion K. Wilson, with extensive modifications by
* James Yonan.
*
* All source code which derives from the CIPE-Win32 project is
* Copyright (C) Damion K. Wilson, 2003, and is released under the
* GPL version 2 (see below).
*
* All other source code is Copyright (C) James Yonan, 2003-2004,
* and is released under the GPL version 2 (see below).
*
* This program 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 2 of the License, or
* (at your option) any later version.
*
* This program 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 (see the file COPYING included with this
* distribution); if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "qemu-common.h"
#include "net/net.h"
#include "sysemu/sysemu.h"
#include <stdio.h>
#include <windows.h>
#include <winioctl.h>
//=============
// TAP IOCTLs
//=============
#define TAP_CONTROL_CODE(request,method) \
CTL_CODE (FILE_DEVICE_UNKNOWN, request, method, FILE_ANY_ACCESS)
#define TAP_IOCTL_GET_MAC TAP_CONTROL_CODE (1, METHOD_BUFFERED)
#define TAP_IOCTL_GET_VERSION TAP_CONTROL_CODE (2, METHOD_BUFFERED)
#define TAP_IOCTL_GET_MTU TAP_CONTROL_CODE (3, METHOD_BUFFERED)
#define TAP_IOCTL_GET_INFO TAP_CONTROL_CODE (4, METHOD_BUFFERED)
#define TAP_IOCTL_CONFIG_POINT_TO_POINT TAP_CONTROL_CODE (5, METHOD_BUFFERED)
#define TAP_IOCTL_SET_MEDIA_STATUS TAP_CONTROL_CODE (6, METHOD_BUFFERED)
#define TAP_IOCTL_CONFIG_DHCP_MASQ TAP_CONTROL_CODE (7, METHOD_BUFFERED)
#define TAP_IOCTL_GET_LOG_LINE TAP_CONTROL_CODE (8, METHOD_BUFFERED)
#define TAP_IOCTL_CONFIG_DHCP_SET_OPT TAP_CONTROL_CODE (9, METHOD_BUFFERED)
//=================
// Registry keys
//=================
#define ADAPTER_KEY "SYSTEM\\CurrentControlSet\\Control\\Class\\{4D36E972-E325-11CE-BFC1-08002BE10318}"
#define NETWORK_CONNECTIONS_KEY "SYSTEM\\CurrentControlSet\\Control\\Network\\{4D36E972-E325-11CE-BFC1-08002BE10318}"
//======================
// Filesystem prefixes
//======================
#define USERMODEDEVICEDIR "\\\\.\\Global\\"
#define TAPSUFFIX ".tap"
//======================
// Compile time configuration
//======================
//#define DEBUG_TAP_WIN32
#define TUN_ASYNCHRONOUS_WRITES 1
#define TUN_BUFFER_SIZE 1560
#define TUN_MAX_BUFFER_COUNT 32
/*
* The data member "buffer" must be the first element in the tun_buffer
* structure. See the function, tap_win32_free_buffer.
*/
typedef struct tun_buffer_s {
unsigned char buffer [TUN_BUFFER_SIZE];
unsigned long read_size;
struct tun_buffer_s* next;
} tun_buffer_t;
typedef struct tap_win32_overlapped {
HANDLE handle;
HANDLE read_event;
HANDLE write_event;
HANDLE output_queue_semaphore;
HANDLE free_list_semaphore;
HANDLE tap_semaphore;
CRITICAL_SECTION output_queue_cs;
CRITICAL_SECTION free_list_cs;
OVERLAPPED read_overlapped;
OVERLAPPED write_overlapped;
tun_buffer_t buffers[TUN_MAX_BUFFER_COUNT];
tun_buffer_t* free_list;
tun_buffer_t* output_queue_front;
tun_buffer_t* output_queue_back;
} tap_win32_overlapped_t;
static tap_win32_overlapped_t tap_overlapped;
static tun_buffer_t* get_buffer_from_free_list(tap_win32_overlapped_t* const overlapped)
{
tun_buffer_t* buffer = NULL;
WaitForSingleObject(overlapped->free_list_semaphore, INFINITE);
EnterCriticalSection(&overlapped->free_list_cs);
buffer = overlapped->free_list;
// assert(buffer != NULL);
overlapped->free_list = buffer->next;
LeaveCriticalSection(&overlapped->free_list_cs);
buffer->next = NULL;
return buffer;
}
static void put_buffer_on_free_list(tap_win32_overlapped_t* const overlapped, tun_buffer_t* const buffer)
{
EnterCriticalSection(&overlapped->free_list_cs);
buffer->next = overlapped->free_list;
overlapped->free_list = buffer;
LeaveCriticalSection(&overlapped->free_list_cs);
ReleaseSemaphore(overlapped->free_list_semaphore, 1, NULL);
}
static tun_buffer_t* get_buffer_from_output_queue(tap_win32_overlapped_t* const overlapped, const int block)
{
tun_buffer_t* buffer = NULL;
DWORD result, timeout = block ? INFINITE : 0L;
// Non-blocking call
result = WaitForSingleObject(overlapped->output_queue_semaphore, timeout);
switch (result)
{
// The semaphore object was signaled.
case WAIT_OBJECT_0:
EnterCriticalSection(&overlapped->output_queue_cs);
buffer = overlapped->output_queue_front;
overlapped->output_queue_front = buffer->next;
if(overlapped->output_queue_front == NULL) {
overlapped->output_queue_back = NULL;
}
LeaveCriticalSection(&overlapped->output_queue_cs);
break;
// Semaphore was nonsignaled, so a time-out occurred.
case WAIT_TIMEOUT:
// Cannot open another window.
break;
}
return buffer;
}
static tun_buffer_t* get_buffer_from_output_queue_immediate (tap_win32_overlapped_t* const overlapped)
{
return get_buffer_from_output_queue(overlapped, 0);
}
static void put_buffer_on_output_queue(tap_win32_overlapped_t* const overlapped, tun_buffer_t* const buffer)
{
EnterCriticalSection(&overlapped->output_queue_cs);
if(overlapped->output_queue_front == NULL && overlapped->output_queue_back == NULL) {
overlapped->output_queue_front = overlapped->output_queue_back = buffer;
} else {
buffer->next = NULL;
overlapped->output_queue_back->next = buffer;
overlapped->output_queue_back = buffer;
}
LeaveCriticalSection(&overlapped->output_queue_cs);
ReleaseSemaphore(overlapped->output_queue_semaphore, 1, NULL);
}
static int is_tap_win32_dev(const char *guid)
{
HKEY netcard_key;
LONG status;
DWORD len;
int i = 0;
status = RegOpenKeyEx(
HKEY_LOCAL_MACHINE,
ADAPTER_KEY,
0,
KEY_READ,
&netcard_key);
if (status != ERROR_SUCCESS) {
return FALSE;
}
for (;;) {
char enum_name[256];
char unit_string[256];
HKEY unit_key;
char component_id_string[] = "ComponentId";
char component_id[256];
char net_cfg_instance_id_string[] = "NetCfgInstanceId";
char net_cfg_instance_id[256];
DWORD data_type;
len = sizeof (enum_name);
status = RegEnumKeyEx(
netcard_key,
i,
enum_name,
&len,
NULL,
NULL,
NULL,
NULL);
if (status == ERROR_NO_MORE_ITEMS)
break;
else if (status != ERROR_SUCCESS) {
return FALSE;
}
snprintf (unit_string, sizeof(unit_string), "%s\\%s",
ADAPTER_KEY, enum_name);
status = RegOpenKeyEx(
HKEY_LOCAL_MACHINE,
unit_string,
0,
KEY_READ,
&unit_key);
if (status != ERROR_SUCCESS) {
return FALSE;
} else {
len = sizeof (component_id);
status = RegQueryValueEx(
unit_key,
component_id_string,
NULL,
&data_type,
(LPBYTE)component_id,
&len);
if (!(status != ERROR_SUCCESS || data_type != REG_SZ)) {
len = sizeof (net_cfg_instance_id);
status = RegQueryValueEx(
unit_key,
net_cfg_instance_id_string,
NULL,
&data_type,
(LPBYTE)net_cfg_instance_id,
&len);
if (status == ERROR_SUCCESS && data_type == REG_SZ) {
if (/* !strcmp (component_id, TAP_COMPONENT_ID) &&*/
!strcmp (net_cfg_instance_id, guid)) {
RegCloseKey (unit_key);
RegCloseKey (netcard_key);
return TRUE;
}
}
}
RegCloseKey (unit_key);
}
++i;
}
RegCloseKey (netcard_key);
return FALSE;
}
static int get_device_guid(
char *name,
int name_size,
char *actual_name,
int actual_name_size)
{
LONG status;
HKEY control_net_key;
DWORD len;
int i = 0;
int stop = 0;
status = RegOpenKeyEx(
HKEY_LOCAL_MACHINE,
NETWORK_CONNECTIONS_KEY,
0,
KEY_READ,
&control_net_key);
if (status != ERROR_SUCCESS) {
return -1;
}
while (!stop)
{
char enum_name[256];
char connection_string[256];
HKEY connection_key;
char name_data[256];
DWORD name_type;
const char name_string[] = "Name";
len = sizeof (enum_name);
status = RegEnumKeyEx(
control_net_key,
i,
enum_name,
&len,
NULL,
NULL,
NULL,
NULL);
if (status == ERROR_NO_MORE_ITEMS)
break;
else if (status != ERROR_SUCCESS) {
return -1;
}
snprintf(connection_string,
sizeof(connection_string),
"%s\\%s\\Connection",
NETWORK_CONNECTIONS_KEY, enum_name);
status = RegOpenKeyEx(
HKEY_LOCAL_MACHINE,
connection_string,
0,
KEY_READ,
&connection_key);
if (status == ERROR_SUCCESS) {
len = sizeof (name_data);
status = RegQueryValueEx(
connection_key,
name_string,
NULL,
&name_type,
(LPBYTE)name_data,
&len);
if (status != ERROR_SUCCESS || name_type != REG_SZ) {
return -1;
}
else {
if (is_tap_win32_dev(enum_name)) {
snprintf(name, name_size, "%s", enum_name);
if (actual_name) {
if (strcmp(actual_name, "") != 0) {
if (strcmp(name_data, actual_name) != 0) {
RegCloseKey (connection_key);
++i;
continue;
}
}
else {
snprintf(actual_name, actual_name_size, "%s", name_data);
}
}
stop = 1;
}
}
RegCloseKey (connection_key);
}
++i;
}
RegCloseKey (control_net_key);
if (stop == 0)
return -1;
return 0;
}
static int tap_win32_set_status(HANDLE handle, int status)
{
unsigned long len = 0;
return DeviceIoControl(handle, TAP_IOCTL_SET_MEDIA_STATUS,
&status, sizeof (status),
&status, sizeof (status), &len, NULL);
}
static void tap_win32_overlapped_init(tap_win32_overlapped_t* const overlapped, const HANDLE handle)
{
overlapped->handle = handle;
overlapped->read_event = CreateEvent(NULL, FALSE, FALSE, NULL);
overlapped->write_event = CreateEvent(NULL, FALSE, FALSE, NULL);
overlapped->read_overlapped.Offset = 0;
overlapped->read_overlapped.OffsetHigh = 0;
overlapped->read_overlapped.hEvent = overlapped->read_event;
overlapped->write_overlapped.Offset = 0;
overlapped->write_overlapped.OffsetHigh = 0;
overlapped->write_overlapped.hEvent = overlapped->write_event;
InitializeCriticalSection(&overlapped->output_queue_cs);
InitializeCriticalSection(&overlapped->free_list_cs);
overlapped->output_queue_semaphore = CreateSemaphore(
NULL, // default security attributes
0, // initial count
TUN_MAX_BUFFER_COUNT, // maximum count
NULL); // unnamed semaphore
if(!overlapped->output_queue_semaphore) {
fprintf(stderr, "error creating output queue semaphore!\n");
}
overlapped->free_list_semaphore = CreateSemaphore(
NULL, // default security attributes
TUN_MAX_BUFFER_COUNT, // initial count
TUN_MAX_BUFFER_COUNT, // maximum count
NULL); // unnamed semaphore
if(!overlapped->free_list_semaphore) {
fprintf(stderr, "error creating free list semaphore!\n");
}
overlapped->free_list = overlapped->output_queue_front = overlapped->output_queue_back = NULL;
{
unsigned index;
for(index = 0; index < TUN_MAX_BUFFER_COUNT; index++) {
tun_buffer_t* element = &overlapped->buffers[index];
element->next = overlapped->free_list;
overlapped->free_list = element;
}
}
/* To count buffers, initially no-signal. */
overlapped->tap_semaphore = CreateSemaphore(NULL, 0, TUN_MAX_BUFFER_COUNT, NULL);
if(!overlapped->tap_semaphore)
fprintf(stderr, "error creating tap_semaphore.\n");
}
static int tap_win32_write(tap_win32_overlapped_t *overlapped,
const void *buffer, unsigned long size)
{
unsigned long write_size;
BOOL result;
DWORD error;
result = GetOverlappedResult( overlapped->handle, &overlapped->write_overlapped,
&write_size, FALSE);
if (!result && GetLastError() == ERROR_IO_INCOMPLETE)
WaitForSingleObject(overlapped->write_event, INFINITE);
result = WriteFile(overlapped->handle, buffer, size,
&write_size, &overlapped->write_overlapped);
if (!result) {
switch (error = GetLastError())
{
case ERROR_IO_PENDING:
#ifndef TUN_ASYNCHRONOUS_WRITES
WaitForSingleObject(overlapped->write_event, INFINITE);
#endif
break;
default:
return -1;
}
}
return 0;
}
static DWORD WINAPI tap_win32_thread_entry(LPVOID param)
{
tap_win32_overlapped_t *overlapped = (tap_win32_overlapped_t*)param;
unsigned long read_size;
BOOL result;
DWORD dwError;
tun_buffer_t* buffer = get_buffer_from_free_list(overlapped);
for (;;) {
result = ReadFile(overlapped->handle,
buffer->buffer,
sizeof(buffer->buffer),
&read_size,
&overlapped->read_overlapped);
if (!result) {
dwError = GetLastError();
if (dwError == ERROR_IO_PENDING) {
WaitForSingleObject(overlapped->read_event, INFINITE);
result = GetOverlappedResult( overlapped->handle, &overlapped->read_overlapped,
&read_size, FALSE);
if (!result) {
#ifdef DEBUG_TAP_WIN32
LPVOID lpBuffer;
dwError = GetLastError();
FormatMessage( FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM,
NULL, dwError, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
(LPTSTR) & lpBuffer, 0, NULL );
fprintf(stderr, "Tap-Win32: Error GetOverlappedResult %d - %s\n", dwError, lpBuffer);
LocalFree( lpBuffer );
#endif
}
} else {
#ifdef DEBUG_TAP_WIN32
LPVOID lpBuffer;
FormatMessage( FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM,
NULL, dwError, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
(LPTSTR) & lpBuffer, 0, NULL );
fprintf(stderr, "Tap-Win32: Error ReadFile %d - %s\n", dwError, lpBuffer);
LocalFree( lpBuffer );
#endif
}
}
if(read_size > 0) {
buffer->read_size = read_size;
put_buffer_on_output_queue(overlapped, buffer);
ReleaseSemaphore(overlapped->tap_semaphore, 1, NULL);
buffer = get_buffer_from_free_list(overlapped);
}
}
return 0;
}
static int tap_win32_read(tap_win32_overlapped_t *overlapped,
uint8_t **pbuf, int max_size)
{
int size = 0;
tun_buffer_t* buffer = get_buffer_from_output_queue_immediate(overlapped);
if(buffer != NULL) {
*pbuf = buffer->buffer;
size = (int)buffer->read_size;
if(size > max_size) {
size = max_size;
}
}
return size;
}
static void tap_win32_free_buffer(tap_win32_overlapped_t *overlapped,
uint8_t *pbuf)
{
tun_buffer_t* buffer = (tun_buffer_t*)pbuf;
put_buffer_on_free_list(overlapped, buffer);
}
static int tap_win32_open(tap_win32_overlapped_t **phandle,
const char *prefered_name)
{
char device_path[256];
char device_guid[0x100];
int rc;
HANDLE handle;
BOOL bret;
char name_buffer[0x100] = {0, };
struct {
unsigned long major;
unsigned long minor;
unsigned long debug;
} version;
DWORD version_len;
DWORD idThread;
HANDLE hThread;
if (prefered_name != NULL)
snprintf(name_buffer, sizeof(name_buffer), "%s", prefered_name);
rc = get_device_guid(device_guid, sizeof(device_guid), name_buffer, sizeof(name_buffer));
if (rc)
return -1;
snprintf (device_path, sizeof(device_path), "%s%s%s",
USERMODEDEVICEDIR,
device_guid,
TAPSUFFIX);
handle = CreateFile (
device_path,
GENERIC_READ | GENERIC_WRITE,
0,
0,
OPEN_EXISTING,
FILE_ATTRIBUTE_SYSTEM | FILE_FLAG_OVERLAPPED,
0 );
if (handle == INVALID_HANDLE_VALUE) {
return -1;
}
bret = DeviceIoControl(handle, TAP_IOCTL_GET_VERSION,
&version, sizeof (version),
&version, sizeof (version), &version_len, NULL);
if (bret == FALSE) {
CloseHandle(handle);
return -1;
}
if (!tap_win32_set_status(handle, TRUE)) {
return -1;
}
tap_win32_overlapped_init(&tap_overlapped, handle);
*phandle = &tap_overlapped;
hThread = CreateThread(NULL, 0, tap_win32_thread_entry,
(LPVOID)&tap_overlapped, 0, &idThread);
return 0;
}
/********************************************/
typedef struct TAPState {
VLANClientState *vc;
tap_win32_overlapped_t *handle;
} TAPState;
static void tap_cleanup(VLANClientState *vc)
{
TAPState *s = vc->opaque;
qemu_del_wait_object(s->handle->tap_semaphore, NULL, NULL);
/* FIXME: need to kill thread and close file handle:
tap_win32_close(s);
*/
g_free(s);
}
static ssize_t tap_receive(VLANClientState *vc, const uint8_t *buf, size_t size)
{
TAPState *s = vc->opaque;
return tap_win32_write(s->handle, buf, size);
}
static void tap_win32_send(void *opaque)
{
TAPState *s = opaque;
uint8_t *buf;
int max_size = 4096;
int size;
size = tap_win32_read(s->handle, &buf, max_size);
if (size > 0) {
qemu_send_packet(s->vc, buf, size);
tap_win32_free_buffer(s->handle, buf);
}
}
int tap_win32_init(VLANState *vlan, const char *model,
const char *name, const char *ifname)
{
TAPState *s;
s = g_malloc0(sizeof(TAPState));
if (!s)
return -1;
if (tap_win32_open(&s->handle, ifname) < 0) {
printf("tap: Could not open '%s'\n", ifname);
return -1;
}
s->vc = qemu_new_vlan_client(vlan, model, name, NULL, tap_receive,
NULL, tap_cleanup, s);
snprintf(s->vc->info_str, sizeof(s->vc->info_str),
"tap: ifname=%s", ifname);
qemu_add_wait_object(s->handle->tap_semaphore, tap_win32_send, s);
return 0;
}