Add OVPN_MP_START_VPN ioctl

This starts listening on a provided local address. OpenVPN#82 Co-authored-by: Leon Dang <[email protected]> Signed-off-by: Leon Dang <[email protected]> Signed-off-by: Lev Stipakov <[email protected]>
lstipakov · Sep 16, 2024 · 83d2ad7 · 83d2ad7
1 parent 9010a30
commit 83d2ad7
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Showing 5 changed files with 100 additions and 10 deletions.
diff --git a/.gitignore b/.gitignore
@@ -53,6 +53,7 @@ Thumbs.db
 Debug
 Release
 x64
+x86
 Win32
 sdv
 ARM64
@@ -72,3 +73,9 @@ smvstats.txt
 *.cab
 
 *.vcxproj.user
+
+**/out
+**/build
+**/.vscode
+**/signed
+msm/tmp
diff --git a/Driver.cpp b/Driver.cpp
@@ -264,17 +264,23 @@ OvpnSetMode(POVPN_DEVICE device, WDFREQUEST request)
 static BOOLEAN
 OvpnDeviceCheckMode(OVPN_MODE mode, ULONG code)
 {
-    if (mode == OVPN_MODE_MP)
-    {
-        switch (code)
-        {
+    if (mode == OVPN_MODE_MP) {
+        switch (code) {
         // all those IOCTLs are only for P2P mode
         case OVPN_IOCTL_NEW_PEER:
         case OVPN_IOCTL_DEL_PEER:
         case OVPN_IOCTL_NEW_KEY:
         case OVPN_IOCTL_NEW_KEY_V2:
         case OVPN_IOCTL_SWAP_KEYS:
         case OVPN_IOCTL_SET_PEER:
+        case OVPN_IOCTL_START_VPN:
+            return FALSE;
+        }
+    }
+    else if (mode == OVPN_MODE_P2P) {
+        switch (code) {
+        // those IOCTLs are for MP mode
+        case OVPN_IOCTL_MP_START_VPN:
             return FALSE;
         }
     }
@@ -323,6 +329,63 @@ OvpnStopVPN(_In_ POVPN_DEVICE device)
     return STATUS_SUCCESS;
 }
 
+_Must_inspect_result_
+_IRQL_requires_(PASSIVE_LEVEL)
+_IRQL_requires_same_
+NTSTATUS
+OvpnMPStartVPN(POVPN_DEVICE device, WDFREQUEST request, ULONG_PTR* bytesReturned)
+{
+    NTSTATUS status = STATUS_SUCCESS;
+
+    LOG_ENTER();
+
+    KIRQL kirql = ExAcquireSpinLockExclusive(&device->SpinLock);
+    if (device->Socket.Socket != NULL) {
+        ExReleaseSpinLockExclusive(&device->SpinLock, kirql);
+
+        status = STATUS_ALREADY_INITIALIZED;
+
+        goto done;
+    }
+    else {
+        ExReleaseSpinLockExclusive(&device->SpinLock, kirql);
+
+        POVPN_MP_START_VPN addrIn = NULL;
+        GOTO_IF_NOT_NT_SUCCESS(done, status, WdfRequestRetrieveInputBuffer(request, sizeof(OVPN_MP_START_VPN), (PVOID*)&addrIn, NULL));
+
+        PWSK_SOCKET socket = NULL;
+        POVPN_DRIVER driver = OvpnGetDriverContext(WdfGetDriver());
+
+        // Bind to the address provided
+        status = OvpnSocketInit(&driver->WskProviderNpi, &driver->WskRegistration,
+            addrIn->ListenAddress.Addr4.sin_family, false,
+            (PSOCKADDR)&addrIn->ListenAddress, NULL,
+            0, device, &socket);
+        if (!NT_SUCCESS(status)) {
+            LOG_ERROR("Socket create failed", TraceLoggingValue((UINT32)status),
+                TraceLoggingHexUInt32(*(UINT32*)(&addrIn->ListenAddress.Addr4.sin_addr), "addr"));
+            goto done;
+        }
+
+        kirql = ExAcquireSpinLockExclusive(&device->SpinLock);
+        device->Socket.Socket = socket;
+        ExReleaseSpinLockExclusive(&device->SpinLock, kirql);
+
+        // we might bind the socket to port 0 and we want to get actual port back to userspace
+        POVPN_MP_START_VPN addrOut = NULL;
+        GOTO_IF_NOT_NT_SUCCESS(done, status, WdfRequestRetrieveOutputBuffer(request, sizeof(OVPN_MP_START_VPN), (PVOID*)&addrOut, NULL));
+        RtlCopyMemory(addrOut, addrIn, sizeof(OVPN_MP_START_VPN));
+        *bytesReturned = sizeof(OVPN_MP_START_VPN);
+    }
+
+    OvpnAdapterSetLinkState(OvpnGetAdapterContext(device->Adapter), MediaConnectStateConnected);
+
+done:
+    LOG_EXIT();
+
+    return status;
+}
+
 EVT_WDF_IO_QUEUE_IO_DEVICE_CONTROL OvpnEvtIoDeviceControl;
 
 _Use_decl_annotations_
@@ -397,6 +460,10 @@ OvpnEvtIoDeviceControl(WDFQUEUE queue, WDFREQUEST request, size_t outputBufferLe
         ExReleaseSpinLockExclusive(&device->SpinLock, kirql);
         break;
 
+    case OVPN_IOCTL_MP_START_VPN:
+        status = OvpnMPStartVPN(device, request, &bytesReturned);
+        break;
+
     default:
         LOG_WARN("Unknown <ioControlCode>", TraceLoggingValue(ioControlCode, "ioControlCode"));
         status = STATUS_INVALID_DEVICE_REQUEST;

diff --git a/socket.cpp b/socket.cpp
@@ -522,13 +522,20 @@ OvpnSocketInit(WSK_PROVIDER_NPI* wskProviderNpi, WSK_REGISTRATION* wskRegistrati
             return datagramDispatch->WskBind(*socket, localAddr, 0, irp);
         }, [](PIRP) {}));
 
-        // set remote
-        PWSK_PROVIDER_BASIC_DISPATCH basicDispatch = (PWSK_PROVIDER_BASIC_DISPATCH)(*socket)->Dispatch;
-
-        GOTO_IF_NOT_NT_SUCCESS(error, status, OvpnSocketSyncOp("SetRemote", [basicDispatch, socket, remoteAddrSize, remoteAddr](PIRP irp) {
-            return basicDispatch->WskControlSocket(*socket, WskIoctl, SIO_WSK_SET_REMOTE_ADDRESS, 0, remoteAddrSize, remoteAddr, 0, NULL, NULL, irp);
+        // get the locally bound address for the socket
+        GOTO_IF_NOT_NT_SUCCESS(error, status, OvpnSocketSyncOp("GetLocalAddr", [datagramDispatch, socket, localAddr](PIRP irp) {
+            return datagramDispatch->WskGetLocalAddress(*socket, localAddr, irp);
         }, [](PIRP) {}));
 
+        if (remoteAddr != NULL) {
+            // set remote
+            PWSK_PROVIDER_BASIC_DISPATCH basicDispatch = (PWSK_PROVIDER_BASIC_DISPATCH)(*socket)->Dispatch;
+
+            GOTO_IF_NOT_NT_SUCCESS(error, status, OvpnSocketSyncOp("SetRemote", [basicDispatch, socket, remoteAddrSize, remoteAddr](PIRP irp) {
+                return basicDispatch->WskControlSocket(*socket, WskIoctl, SIO_WSK_SET_REMOTE_ADDRESS, 0, remoteAddrSize, remoteAddr, 0, NULL, NULL, irp);
+                }, [](PIRP) {}));
+        }
+
         // enable ReceiveFrom event
         eventCallbackControl.NpiId = &NPI_WSK_INTERFACE_ID;
         eventCallbackControl.EventMask = WSK_EVENT_RECEIVE_FROM;

diff --git a/socket.h b/socket.h
@@ -60,7 +60,7 @@ _Must_inspect_result_
 _IRQL_requires_(PASSIVE_LEVEL)
 NTSTATUS
 OvpnSocketInit(_In_ WSK_PROVIDER_NPI* wskProviderNpi, _In_ WSK_REGISTRATION* wskRegistration, ADDRESS_FAMILY addrFamily,
-	BOOLEAN tcp, _In_ PSOCKADDR localAddr, _In_ PSOCKADDR remoteAddr, SIZE_T remoteAddrSize,
+	BOOLEAN tcp, _In_ PSOCKADDR localAddr, _In_opt_ PSOCKADDR remoteAddr, SIZE_T remoteAddrSize,
 	_In_ PVOID deviceContext, _Out_ PWSK_SOCKET* socket);
 
 _Must_inspect_result_

diff --git a/uapi/ovpn-dco.h b/uapi/ovpn-dco.h
@@ -123,6 +123,13 @@ typedef struct _OVPN_SET_MODE {
     OVPN_MODE Mode;
 } OVPN_SET_MODE, * POVPN_SET_MODE;
 
+typedef struct _OVPN_MP_START_VPN {
+    union {
+        SOCKADDR_IN Addr4;
+        SOCKADDR_IN6 Addr6;
+    } ListenAddress;
+} OVPN_MP_START_VPN, * POVPN_MP_START_VPN;
+
 #define OVPN_IOCTL_NEW_PEER     CTL_CODE(FILE_DEVICE_UNKNOWN, 1, METHOD_BUFFERED, FILE_ANY_ACCESS)
 #define OVPN_IOCTL_GET_STATS    CTL_CODE(FILE_DEVICE_UNKNOWN, 2, METHOD_BUFFERED, FILE_ANY_ACCESS)
 #define OVPN_IOCTL_NEW_KEY      CTL_CODE(FILE_DEVICE_UNKNOWN, 3, METHOD_BUFFERED, FILE_ANY_ACCESS)
@@ -133,3 +140,5 @@ typedef struct _OVPN_SET_MODE {
 #define OVPN_IOCTL_GET_VERSION  CTL_CODE(FILE_DEVICE_UNKNOWN, 8, METHOD_BUFFERED, FILE_ANY_ACCESS)
 #define OVPN_IOCTL_NEW_KEY_V2   CTL_CODE(FILE_DEVICE_UNKNOWN, 9, METHOD_BUFFERED, FILE_ANY_ACCESS)
 #define OVPN_IOCTL_SET_MODE     CTL_CODE(FILE_DEVICE_UNKNOWN, 10, METHOD_BUFFERED, FILE_ANY_ACCESS)
+
+#define OVPN_IOCTL_MP_START_VPN   CTL_CODE(FILE_DEVICE_UNKNOWN, 11, METHOD_BUFFERED, FILE_ANY_ACCESS)