api: introduce wintun.h

The SDK header for deployment containing datatype and function
declarations for use by C/C++ clients.

As we shall not distribute MSVC wintun.lib files, making clients need to
use GetProcAddress(), this file contains function type declarations
rather then __declspec(dllimport) function declarations.

Signed-off-by: Simon Rozman <simon@rozman.si>

1 files changed, 211 insertions, 0 deletions

diff --git a/api/wintun.h b/api/wintun.h
new file mode 100644
index 0000000..0917a6c
--- /dev/null
+++ b/api/wintun.h
@@ -0,0 +1,211 @@
+/* SPDX-License-Identifier: GPL-2.0
+ *
+ * Copyright (C) 2018-2020 WireGuard LLC. All Rights Reserved.
+ */
+
+#pragma once
+
+#include <Windows.h>
+#include <IPExport.h>
+
+typedef _Return_type_success_(return == ERROR_SUCCESS) DWORD WINTUN_STATUS;
+
+/**
+ * A handle representing Wintun adapter
+ */
+typedef void *WINTUN_ADAPTER_HANDLE;
+
+#define MAX_POOL 256
+
+/**
+ * Creates a Wintun adapter.
+ *
+ * @param Pool          Name of the adapter pool.
+ *
+ * @param Name          The requested name of the adapter.
+ *
+ * @param RequestedGUID  The GUID of the created network adapter, which then influences NLA generation
+ *                      deterministically. If it is set to NULL, the GUID is chosen by the system at random, and hence
+ *                      a new NLA entry is created for each new adapter. It is called "requested" GUID because the API
+ *                      it uses is completely undocumented, and so there could be minor interesting complications with
+ *                      its usage.
+ *
+ * @param Adapter       Pointer to a handle to receive the adapter handle. Must be released with
+ *                      WintunFreeAdapter.
+ *
+ * @param RebootRequired  Pointer to a boolean flag to be set to TRUE in case SetupAPI suggests a reboot. Must be
+ *                      initialised to FALSE manually before this function is called.
+ *
+ * @return ERROR_SUCCESS on success; Win32 error code otherwise.
+ */
+typedef WINTUN_STATUS(WINAPI *WINTUN_CREATE_ADAPTER_FUNC)(
+    _In_z_count_c_(MAX_POOL) const WCHAR *Pool,
+    _In_z_count_c_(MAX_ADAPTER_NAME) const WCHAR *Name,
+    _In_opt_ const GUID *RequestedGUID,
+    _Out_ WINTUN_ADAPTER_HANDLE *Adapter,
+    _Inout_ BOOL *RebootRequired);
+
+/**
+ * Deletes a Wintun adapter.
+ *
+ * @param Adapter       Adapter handle obtained with WintunGetAdapter or WintunCreateAdapter.
+ *
+ * @param RebootRequired  Pointer to a boolean flag to be set to TRUE in case SetupAPI suggests a reboot. Must be
+ *                      initialised to FALSE manually before this function is called.
+ *
+ * @return ERROR_SUCCESS on success or the adapter was not found; Win32 error code otherwise.
+ */
+typedef WINTUN_STATUS(
+    WINAPI *WINTUN_DELETE_ADAPTER_FUNC)(_In_ WINTUN_ADAPTER_HANDLE Adapter, _Inout_ BOOL *RebootRequired);
+
+/**
+ * Called by WintunEnumAdapters for each adapter in the pool.
+ *
+ * @param Adapter       Adapter handle.
+ *
+ * @param Param         An application-defined value passed to the WintunEnumAdapters.
+ *
+ * @return Non-zero to continue iterating adapters; zero to stop.
+ */
+typedef BOOL(CALLBACK *WINTUN_ENUM_FUNC)(_In_ WINTUN_ADAPTER_HANDLE Adapter, _In_ LPARAM Param);
+
+/**
+ * Enumerates all Wintun adapters.
+ *
+ * @param Pool          Name of the adapter pool.
+ *
+ * @param Func          Callback function. To continue enumeration, the callback function must return TRUE; to stop
+ *                      enumeration, it must return FALSE.
+ *
+ * @param Param         An application-defined value to be passed to the callback function.
+ *
+ * @return ERROR_SUCCESS on success; Win32 error code otherwise.
+ */
+typedef WINTUN_STATUS(WINAPI *WINTUN_ENUM_ADAPTERS_FUNC)(
+    _In_z_count_c_(MAX_POOL) const WCHAR *Pool,
+    _In_ WINTUN_ENUM_FUNC Func,
+    _In_ LPARAM Param);
+
+/**
+ * Releases Wintun adapter resources.
+ *
+ * @param Adapter       Adapter handle obtained with WintunGetAdapter or WintunCreateAdapter.
+ */
+typedef void(WINAPI *WINTUN_FREE_ADAPTER_FUNC)(_In_ WINTUN_ADAPTER_HANDLE Adapter);
+
+/**
+ * Finds a Wintun adapter by its name.
+ *
+ * @param Pool          Name of the adapter pool.
+ *
+ * @param Name          Adapter name.
+ *
+ * @param Adapter       Pointer to a handle to receive the adapter handle. Must be released with WintunFreeAdapter.
+ *
+ * @return ERROR_SUCCESS on success; ERROR_FILE_NOT_FOUND if adapter with given name is not found; ERROR_ALREADY_EXISTS
+ * if adapter is found but not a Wintun-class or not a member of the pool; Win32 error code otherwise
+ */
+typedef WINTUN_STATUS(WINAPI *WINTUN_GET_ADAPTER_FUNC)(
+    _In_z_count_c_(MAX_POOL) const WCHAR *Pool,
+    _In_z_count_c_(MAX_ADAPTER_NAME) const WCHAR *Name,
+    _Out_ WINTUN_ADAPTER_HANDLE *Adapter);
+
+/**
+ * Returns a handle to the adapter device object.
+ *
+ * @param Adapter       Adapter handle obtained with WintunGetAdapter or WintunCreateAdapter.
+ *
+ * @param Handle        Pointer to receive the adapter device object handle. Must be released with CloseHandle.
+ *
+ * @return ERROR_SUCCESS on success; Win32 error code otherwise.
+ */
+typedef WINTUN_STATUS(
+    WINAPI *WINTUN_GET_ADAPTER_DEVICE_OBJECT_FUNC)(_In_ WINTUN_ADAPTER_HANDLE Adapter, _Out_ HANDLE *Handle);
+
+/**
+ * Returns the GUID of the adapter.
+ *
+ * @param Adapter       Adapter handle obtained with WintunGetAdapter or WintunCreateAdapter
+ *
+ * @param Guid          Pointer to GUID to receive adapter ID.
+ */
+typedef void(WINAPI *WINTUN_GET_ADAPTER_GUID_FUNC)(_In_ WINTUN_ADAPTER_HANDLE Adapter, _Out_ GUID *Guid);
+
+/**
+ * Returns the LUID of the adapter.
+ *
+ * @param Adapter       Adapter handle obtained with WintunGetAdapter or WintunCreateAdapter
+ *
+ * @param Luid          Pointer to LUID to receive adapter LUID.
+ */
+typedef void(WINAPI *WINTUN_GET_ADAPTER_LUID_FUNC)(_In_ WINTUN_ADAPTER_HANDLE Adapter, _Out_ LUID *Luid);
+
+/**
+ * Returns the name of the Wintun adapter.
+ *
+ * @param Adapter       Adapter handle obtained with WintunGetAdapter or WintunCreateAdapter
+ *
+ * @param Name          Pointer to a string to receive adapter name
+ *
+ * @return ERROR_SUCCESS on success; Win32 error code otherwise.
+ */
+typedef WINTUN_STATUS(WINAPI *WINTUN_GET_ADAPTER_NAME_FUNC)(
+    _In_ WINTUN_ADAPTER_HANDLE Adapter,
+    _Out_cap_c_(MAX_ADAPTER_NAME) WCHAR *Name);
+
+/**
+ * Returns the version of the Wintun driver and NDIS system currently loaded.
+ *
+ * @param DriverVersionMaj  Pointer to a DWORD to receive the Wintun driver major version number.
+ *
+ * @param DriverVersionMin  Pointer to a DWORD to receive the Wintun driver minor version number.
+ *
+ * @param NdisVersionMaj  Pointer to a DWORD to receive the NDIS major version number.
+ *
+ * @param NdisVersionMin  Pointer to a DWORD to receive the NDIS minor version number.
+ *
+ * @return ERROR_SUCCESS on success; Win32 error code otherwise.
+ */
+typedef WINTUN_STATUS(WINAPI *WINTUN_GET_VERSION_FUNC)(
+    _Out_ DWORD *DriverVersionMaj,
+    _Out_ DWORD *DriverVersionMin,
+    _Out_ DWORD *NdisVersionMaj,
+    _Out_ DWORD *NdisVersionMin);
+
+/**
+ * Sets name of the Wintun adapter.
+ *
+ * @param Adapter       Adapter handle obtained with WintunGetAdapter or WintunCreateAdapter
+ *
+ * @param Name          Adapter name
+ *
+ * @return ERROR_SUCCESS on success; Win32 error code otherwise.
+ */
+typedef WINTUN_STATUS(WINAPI *WINTUN_SET_ADAPTER_NAME_FUNC)(
+    _In_ WINTUN_ADAPTER_HANDLE Adapter,
+    _In_z_count_c_(MAX_ADAPTER_NAME) const WCHAR *Name);
+
+typedef enum _WINTUN_LOGGER_LEVEL
+{
+    WINTUN_LOG_INFO = 0,
+    WINTUN_LOG_WARN,
+    WINTUN_LOG_ERR
+} WINTUN_LOGGER_LEVEL;
+
+/**
+ * Called by internal logger to report diagnostic messages
+ *
+ * @param Level         Message level.
+ *
+ * @param Message       Message text.
+ *
+ * @return Anything - return value is ignored.
+ */
+typedef BOOL(CALLBACK *WINTUN_LOGGER_FUNC)(_In_ WINTUN_LOGGER_LEVEL Level, _In_z_ const WCHAR *Message);
+
+/**
+ * Sets logger callback function.
+ *
+ * @param NewLogger     Pointer to callback function to use as a new global logger.
+ */
+typedef void(WINAPI *WINTUN_SET_LOGGER_FUNC)(_In_ WINTUN_LOGGER_FUNC NewLogger);