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-rw-r--r--driver/wintun.c130
1 files changed, 89 insertions, 41 deletions
diff --git a/driver/wintun.c b/driver/wintun.c
index 931b7e8..4224642 100644
--- a/driver/wintun.c
+++ b/driver/wintun.c
@@ -12,6 +12,7 @@
#pragma warning(disable : 4100) /* unreferenced formal parameter */
#pragma warning(disable : 4200) /* nonstandard: zero-sized array in struct/union */
+#pragma warning(disable : 4201) /* nonstandard extension used: nameless struct/union */
#pragma warning(disable : 4204) /* nonstandard: non-constant aggregate initializer */
#pragma warning(disable : 4221) /* nonstandard: cannot be initialized using address of automatic variable */
#pragma warning(disable : 6320) /* exception-filter expression is the constant EXCEPTION_EXECUTE_HANDLER */
@@ -30,13 +31,15 @@
/* Maximum IP packet size */
#define TUN_MAX_IP_PACKET_SIZE 0xFFFF
/* Maximum packet size */
-#define TUN_MAX_PACKET_SIZE TUN_ALIGN(sizeof(TUN_PACKET) + TUN_MAX_IP_PACKET_SIZE)
+#define TUN_MAX_PACKET_SIZE(LeadPadding, TrailPadding) \
+ TUN_ALIGN(sizeof(TUN_PACKET) + (LeadPadding) + TUN_MAX_IP_PACKET_SIZE + (TrailPadding))
/* Minimum ring capacity. */
#define TUN_MIN_RING_CAPACITY 0x20000 /* 128kiB */
/* Maximum ring capacity. */
#define TUN_MAX_RING_CAPACITY 0x4000000 /* 64MiB */
/* Calculates ring capacity */
-#define TUN_RING_CAPACITY(Size) ((Size) - sizeof(TUN_RING) - (TUN_MAX_PACKET_SIZE - TUN_ALIGNMENT))
+#define TUN_RING_CAPACITY(Size, LeadPadding, TrailPadding) \
+ ((Size) - sizeof(TUN_RING) - (TUN_MAX_PACKET_SIZE(LeadPadding, TrailPadding) - TUN_ALIGNMENT))
/* Calculates ring offset modulo capacity */
#define TUN_RING_WRAP(Value, Capacity) ((Value) & (Capacity - 1))
@@ -60,8 +63,7 @@ typedef struct _TUN_PACKET
ULONG Size;
/* Packet data */
- UCHAR _Field_size_bytes_(Size)
- Data[];
+ UCHAR Data[];
} TUN_PACKET;
typedef struct _TUN_RING
@@ -82,42 +84,64 @@ typedef struct _TUN_RING
UCHAR Data[];
} TUN_RING;
-typedef struct _TUN_REGISTER_RINGS
+/* Obsolete: See TUN_REGISTER_RINGS */
+typedef struct _TUN_REGISTER_RINGS_V1
{
struct
{
- /* Size of the ring */
ULONG RingSize;
-
- /* Pointer to client allocated ring */
TUN_RING *Ring;
-
- /* On send: An event created by the client the Wintun signals after it moves the Tail member of the send ring.
- * On receive: An event created by the client the client will signal when it moves the Tail member of
- * the receive ring if receive ring is alertable. */
HANDLE TailMoved;
} Send, Receive;
-} TUN_REGISTER_RINGS;
+} TUN_REGISTER_RINGS_V1;
#ifdef _WIN64
-typedef struct _TUN_REGISTER_RINGS_32
+/* Obsolete: See TUN_REGISTER_RINGS */
+typedef struct _TUN_REGISTER_RINGS_V1_32
{
struct
{
- /* Size of the ring */
ULONG RingSize;
-
- /* 32-bit addres of client allocated ring */
ULONG Ring;
-
- /* On send: An event created by the client the Wintun signals after it moves the Tail member of the send ring.
- * On receive: An event created by the client the client will signal when it moves the Tail member of
- * the receive ring if receive ring is alertable. */
ULONG TailMoved;
} Send, Receive;
-} TUN_REGISTER_RINGS_32;
+} TUN_REGISTER_RINGS_V1_32;
#endif
+typedef struct _TUN_REGISTER_RINGS_V2
+{
+ struct
+ {
+ /* Size of the ring */
+ ULONG RingSize;
+
+ /* Extra space before each packet data */
+ ULONG LeadPadding;
+
+ /* Extra space after each packet data */
+ ULONG TrailPadding;
+
+ union
+ {
+ /* Address of client allocated ring */
+ TUN_RING *Ring;
+ ULONG64 RingAddress;
+ };
+
+ union
+ {
+ /* On send: An event handle created by the client the Wintun signals after it moves the Tail member of the
+ * send ring.
+ * On receive: An event handle created by the client the client will signal when it moves the Tail member
+ * of the receive ring if receive ring is alertable. */
+ HANDLE TailMoved;
+ ULONG64 TailMovedHandle;
+ };
+ } Send, Receive;
+} TUN_REGISTER_RINGS_V2;
+
+#define TUN_REGISTER_RINGS TUN_REGISTER_RINGS_V2
+
/* Register rings hosted by the client.
* The lpInBuffer and nInBufferSize parameters of DeviceIoControl() must point to an TUN_REGISTER_RINGS struct.
* Client must wait for this IOCTL to finish before adding packets to the ring. */
@@ -151,6 +175,8 @@ typedef struct _TUN_CTX
MDL *Mdl;
TUN_RING *Ring;
ULONG Capacity;
+ ULONG LeadPadding;
+ ULONG TrailPadding;
KEVENT *TailMoved;
KSPIN_LOCK Lock;
ULONG RingTail;
@@ -165,6 +191,8 @@ typedef struct _TUN_CTX
MDL *Mdl;
TUN_RING *Ring;
ULONG Capacity;
+ ULONG LeadPadding;
+ ULONG TrailPadding;
KEVENT *TailMoved;
HANDLE Thread;
KSPIN_LOCK Lock;
@@ -251,6 +279,7 @@ TunSendNetBufferLists(
{
TUN_CTX *Ctx = (TUN_CTX *)MiniportAdapterContext;
LONG64 SentPacketsCount = 0, SentPacketsSize = 0, ErrorPacketsCount = 0, DiscardedPacketsCount = 0;
+ const UINT Padding = Ctx->Device.Send.LeadPadding + Ctx->Device.Send.TrailPadding;
/* Measure NBLs. */
ULONG PacketsCount = 0, RequiredRingSpace = 0;
@@ -262,7 +291,7 @@ TunSendNetBufferLists(
UINT PacketSize = NET_BUFFER_DATA_LENGTH(Nb);
if (PacketSize > TUN_MAX_IP_PACKET_SIZE)
continue; /* The same condition holds down below, where we `goto skipPacket`. */
- RequiredRingSpace += TUN_ALIGN(sizeof(TUN_PACKET) + PacketSize);
+ RequiredRingSpace += TUN_ALIGN(sizeof(TUN_PACKET) + Padding + PacketSize);
}
}
@@ -309,24 +338,25 @@ TunSendNetBufferLists(
TUN_PACKET *Packet = (TUN_PACKET *)(Ring->Data + RingTail);
Packet->Size = PacketSize;
- void *NbData = NdisGetDataBuffer(Nb, PacketSize, Packet->Data, 1, 0);
+ UCHAR *PacketData = Packet->Data + Ctx->Device.Send.LeadPadding;
+ void *NbData = NdisGetDataBuffer(Nb, PacketSize, PacketData, 1, 0);
if (!NbData)
{
/* The space for the packet has already been allocated in the ring. Write a zero-packet rather than
* fixing the gap in the ring. */
- NdisZeroMemory(Packet->Data, PacketSize);
+ NdisZeroMemory(PacketData, PacketSize);
DiscardedPacketsCount++;
NET_BUFFER_LIST_STATUS(Nbl) = NDIS_STATUS_FAILURE;
}
else
{
- if (NbData != Packet->Data)
- NdisMoveMemory(Packet->Data, NbData, PacketSize);
+ if (NbData != PacketData)
+ NdisMoveMemory(PacketData, NbData, PacketSize);
SentPacketsCount++;
SentPacketsSize += PacketSize;
}
- RingTail = TUN_RING_WRAP(RingTail + TUN_ALIGN(sizeof(TUN_PACKET) + PacketSize), RingCapacity);
+ RingTail = TUN_RING_WRAP(RingTail + TUN_ALIGN(sizeof(TUN_PACKET) + Padding + PacketSize), RingCapacity);
continue;
skipPacket:
@@ -441,6 +471,7 @@ TunProcessReceiveData(_Inout_ TUN_CTX *Ctx)
TUN_RING *Ring = Ctx->Device.Receive.Ring;
ULONG RingCapacity = Ctx->Device.Receive.Capacity;
+ const UINT Padding = Ctx->Device.Receive.LeadPadding + Ctx->Device.Receive.TrailPadding;
LARGE_INTEGER Frequency;
KeQueryPerformanceCounter(&Frequency);
ULONG64 SpinMax = Frequency.QuadPart / 1000 / 10; /* 1/10 ms */
@@ -497,18 +528,19 @@ TunProcessReceiveData(_Inout_ TUN_CTX *Ctx)
if (PacketSize > TUN_MAX_IP_PACKET_SIZE)
break;
- ULONG AlignedPacketSize = TUN_ALIGN(sizeof(TUN_PACKET) + PacketSize);
+ ULONG AlignedPacketSize = TUN_ALIGN(sizeof(TUN_PACKET) + Padding + PacketSize);
if (AlignedPacketSize > RingContent)
break;
ULONG NblFlags;
USHORT NblProto;
- if (PacketSize >= 20 && Packet->Data[0] >> 4 == 4)
+ const UCHAR *PacketData = Packet->Data + Ctx->Device.Receive.LeadPadding;
+ if (PacketSize >= 20 && PacketData[0] >> 4 == 4)
{
NblFlags = NDIS_NBL_FLAGS_IS_IPV4;
NblProto = HTONS(NDIS_ETH_TYPE_IPV4);
}
- else if (PacketSize >= 40 && Packet->Data[0] >> 4 == 6)
+ else if (PacketSize >= 40 && PacketData[0] >> 4 == 6)
{
NblFlags = NDIS_NBL_FLAGS_IS_IPV6;
NblProto = HTONS(NDIS_ETH_TYPE_IPV6);
@@ -523,7 +555,7 @@ TunProcessReceiveData(_Inout_ TUN_CTX *Ctx)
IoBuildPartialMdl(
Ctx->Device.Receive.Mdl,
Mdl,
- (UCHAR *)MmGetMdlVirtualAddress(Ctx->Device.Receive.Mdl) + (ULONG)(Packet->Data - (UCHAR *)Ring),
+ (UCHAR *)MmGetMdlVirtualAddress(Ctx->Device.Receive.Mdl) + (ULONG)(PacketData - (UCHAR *)Ring),
PacketSize);
NET_BUFFER_LIST *Nbl = NdisAllocateNetBufferAndNetBufferList(Ctx->NblPool, 0, 0, Mdl, 0, PacketSize);
if (!Nbl)
@@ -595,14 +627,25 @@ TunRegisterBuffers(_Inout_ TUN_CTX *Ctx, _Inout_ IRP *Irp)
goto cleanupMutex;
Ctx->Device.OwningFileObject = Stack->FileObject;
- TUN_REGISTER_RINGS Rrb;
+ TUN_REGISTER_RINGS Rrb = { 0 };
if (Stack->Parameters.DeviceIoControl.InputBufferLength == sizeof(Rrb))
NdisMoveMemory(&Rrb, Irp->AssociatedIrp.SystemBuffer, sizeof(Rrb));
+ else if (Stack->Parameters.DeviceIoControl.InputBufferLength == sizeof(TUN_REGISTER_RINGS_V1))
+ {
+ TUN_REGISTER_RINGS_V1 *RrbV1 = Irp->AssociatedIrp.SystemBuffer;
+ Rrb.Send.RingSize = RrbV1->Send.RingSize;
+ Rrb.Send.Ring = RrbV1->Send.Ring;
+ Rrb.Send.TailMoved = RrbV1->Send.TailMoved;
+ Rrb.Receive.RingSize = RrbV1->Receive.RingSize;
+ Rrb.Receive.Ring = RrbV1->Receive.Ring;
+ Rrb.Receive.TailMoved = RrbV1->Receive.TailMoved;
+ }
#ifdef _WIN64
else if (
- IoIs32bitProcess(Irp) && Stack->Parameters.DeviceIoControl.InputBufferLength == sizeof(TUN_REGISTER_RINGS_32))
+ IoIs32bitProcess(Irp) &&
+ Stack->Parameters.DeviceIoControl.InputBufferLength == sizeof(TUN_REGISTER_RINGS_V1_32))
{
- TUN_REGISTER_RINGS_32 *Rrb32 = Irp->AssociatedIrp.SystemBuffer;
+ TUN_REGISTER_RINGS_V1_32 *Rrb32 = Irp->AssociatedIrp.SystemBuffer;
Rrb.Send.RingSize = Rrb32->Send.RingSize;
Rrb.Send.Ring = (TUN_RING *)Rrb32->Send.Ring;
Rrb.Send.TailMoved = (HANDLE)Rrb32->Send.TailMoved;
@@ -617,15 +660,17 @@ TunRegisterBuffers(_Inout_ TUN_CTX *Ctx, _Inout_ IRP *Irp)
goto cleanupResetOwner;
}
- Ctx->Device.Send.Capacity = TUN_RING_CAPACITY(Rrb.Send.RingSize);
+ Ctx->Device.Send.Capacity = TUN_RING_CAPACITY(Rrb.Send.RingSize, Rrb.Send.LeadPadding, Rrb.Send.TrailPadding);
if (Status = STATUS_INVALID_PARAMETER,
(Ctx->Device.Send.Capacity < TUN_MIN_RING_CAPACITY || Ctx->Device.Send.Capacity > TUN_MAX_RING_CAPACITY ||
!IS_POW2(Ctx->Device.Send.Capacity) || !Rrb.Send.TailMoved || !Rrb.Send.Ring))
goto cleanupResetOwner;
+ Ctx->Device.Send.LeadPadding = Rrb.Send.LeadPadding;
+ Ctx->Device.Send.TrailPadding = Rrb.Send.TrailPadding;
if (!NT_SUCCESS(
Status = ObReferenceObjectByHandle(
- Rrb.Send.TailMoved,
+ (HANDLE)Rrb.Send.TailMoved,
/* We will not wait on send ring tail moved event. */
EVENT_MODIFY_STATE,
*ExEventObjectType,
@@ -634,7 +679,7 @@ TunRegisterBuffers(_Inout_ TUN_CTX *Ctx, _Inout_ IRP *Irp)
NULL)))
goto cleanupResetOwner;
- Ctx->Device.Send.Mdl = IoAllocateMdl(Rrb.Send.Ring, Rrb.Send.RingSize, FALSE, FALSE, NULL);
+ Ctx->Device.Send.Mdl = IoAllocateMdl((PVOID)Rrb.Send.Ring, Rrb.Send.RingSize, FALSE, FALSE, NULL);
if (Status = STATUS_INSUFFICIENT_RESOURCES, !Ctx->Device.Send.Mdl)
goto cleanupSendTailMoved;
try
@@ -653,15 +698,18 @@ TunRegisterBuffers(_Inout_ TUN_CTX *Ctx, _Inout_ IRP *Irp)
if (Status = STATUS_INVALID_PARAMETER, Ctx->Device.Send.RingTail >= Ctx->Device.Send.Capacity)
goto cleanupSendUnlockPages;
- Ctx->Device.Receive.Capacity = TUN_RING_CAPACITY(Rrb.Receive.RingSize);
+ Ctx->Device.Receive.Capacity =
+ TUN_RING_CAPACITY(Rrb.Receive.RingSize, Rrb.Receive.LeadPadding, Rrb.Receive.TrailPadding);
if (Status = STATUS_INVALID_PARAMETER,
(Ctx->Device.Receive.Capacity < TUN_MIN_RING_CAPACITY || Ctx->Device.Receive.Capacity > TUN_MAX_RING_CAPACITY ||
!IS_POW2(Ctx->Device.Receive.Capacity) || !Rrb.Receive.TailMoved || !Rrb.Receive.Ring))
goto cleanupSendUnlockPages;
+ Ctx->Device.Receive.LeadPadding = Rrb.Receive.LeadPadding;
+ Ctx->Device.Receive.TrailPadding = Rrb.Receive.TrailPadding;
if (!NT_SUCCESS(
Status = ObReferenceObjectByHandle(
- Rrb.Receive.TailMoved,
+ (HANDLE)Rrb.Receive.TailMoved,
/* We need to clear receive ring TailMoved event on transition to non-alertable state. */
SYNCHRONIZE | EVENT_MODIFY_STATE,
*ExEventObjectType,
@@ -670,7 +718,7 @@ TunRegisterBuffers(_Inout_ TUN_CTX *Ctx, _Inout_ IRP *Irp)
NULL)))
goto cleanupSendUnlockPages;
- Ctx->Device.Receive.Mdl = IoAllocateMdl(Rrb.Receive.Ring, Rrb.Receive.RingSize, FALSE, FALSE, NULL);
+ Ctx->Device.Receive.Mdl = IoAllocateMdl((PVOID)Rrb.Receive.Ring, Rrb.Receive.RingSize, FALSE, FALSE, NULL);
if (Status = STATUS_INSUFFICIENT_RESOURCES, !Ctx->Device.Receive.Mdl)
goto cleanupReceiveTailMoved;
try
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.