Bump version to 2.2.2 & other fixups

Fix #294

Previous commit was incomplete.

CHANGELOG

@@ -312,3 +312,9 @@ WinDivert 2.2.0
     - Implement new packet parser that correctly handles IP fragments.
     - Add a new "fragment" filter field that matches IP fragments.
     - (Un)Loading the WinDivert driver will cause a system event to be logged.
+WinDivert 2.2.1
+    - Fix potential driver deadlock on user-mode program crash.
+    - Fix filter language simplification bug.
+    - Fix Flow.EndpointId containing junk data.
+WinDivert 2.2.2
+    - Fix potential WinDivertClose() BSOD for WINDIVERT_LAYER_FLOW handles.

README

@@ -5,7 +5,7 @@ WinDivert 2.2: Windows Packet Divert
 ---------------
 
 Windows Packet Divert (WinDivert) is a user-mode packet interception library
-for Windows 7, Windows 8 and Windows 10.
+for Windows 10, Windows 11, and Windows Server.
 
 WinDivert enables user-mode capturing/modifying/dropping of network packets
 sent to/from the Windows network stack.  In summary, WinDivert can:

VERSION

@@ -1 +1 @@
-2.2.0
+2.2.2

doc/windivert.html

@@ -72,7 +72,7 @@
 <p>
 WinDivert is a powerful user-mode 
 capture/sniffing/modification/blocking/re-injection package for
-Windows 7, Windows 8 and Windows 10.
+Windows 10, Windows 11, and Windows Server.
 WinDivert can be used to implement user-mode packet filters, packet sniffers,
 firewalls, NAT, VPNs, tunneling applications, etc., without the need to
 write kernel-mode code.

inf/windivert32.inf

@@ -4,7 +4,7 @@ Class = WFPCALLOUTS
 ClassGuid = {57465043-616C-6C6F-7574-5F636C617373}
 Provider = %Basil%
 CatalogFile = WinDivert32.Cat
-DriverVer = 08/08/2019,2.2.0
+DriverVer = 01/09/2022,2.2.2
 
 [SourceDisksNames]
 1 = %DiskName%

inf/windivert64.inf

@@ -4,7 +4,7 @@ Class = WFPCALLOUTS
 ClassGuid = {57465043-616C-6C6F-7574-5F636C617373}
 Provider = %Basil%
 CatalogFile = WinDivert64.Cat
-DriverVer = 08/08/2019,2.2.0
+DriverVer = 01/09/2022,2.2.2
 
 [SourceDisksNames]
 1 = %DiskName%

sys/windivert.c

@@ -242,9 +242,8 @@ struct packet_s
     UINT32 ip_checksum:1;                   // Packet has IPv4 checksum?
     UINT32 tcp_checksum:1;                  // Packet has TCP checksum?
     UINT32 udp_checksum:1;                  // Packet has UDP checksum?
-    UINT32 icmp_checksum:1;                 // Packet has ICMP(V6) checksum?
     UINT32 match:1;                         // Packet matches filter?
-    UINT32 padding:6;                       // Padding for alignment.
+    UINT32 padding:7;                       // Padding for alignment.
     UINT32 packet_size;                     // Packet total size.
     PVOID object;                           // Object associated with packet.
     UINT32 priority;                        // Packet priority.
@@ -274,8 +273,6 @@ struct flow_s
     UINT64 flow_id;                         // WFP flow ID.
     UINT32 callout_id;                      // WFP callout ID.
     UINT16 layer_id;                        // WFP layout ID.
-    BOOL inserted:1;                        // Flow inserted into context?
-    BOOL deleted:1;                         // Flow deleted from context?
     BOOL outbound:1;                        // Flow is outound?
     BOOL loopback:1;                        // Flow is loopback?
     BOOL ipv6:1;                            // Flow is ipv6?
@@ -348,7 +345,8 @@ static NTSTATUS windivert_write(context_t context, WDFREQUEST request,
     req_context_t req_context);
 static void NTAPI windivert_inject_complete(VOID *context,
     NET_BUFFER_LIST *packets, BOOLEAN dispatch_level);
-static void windivert_inject_packet_too_big(packet_t packet);
+static void NTAPI windivert_reinject_complete(VOID *context,
+    NET_BUFFER_LIST *packets, BOOLEAN dispatch_level);
 static NTSTATUS windivert_notify(IN FWPS_CALLOUT_NOTIFY_TYPE type,
     IN const GUID *filter_key, IN const FWPS_FILTER0 *filter);
 static void windivert_outbound_network_v4_classify(
@@ -469,7 +467,7 @@ static BOOL windivert_queue_work(context_t context, PVOID packet,
     UINT64 flags, UINT32 priority, BOOL ipv4, BOOL outbound, BOOL loopback,
     BOOL impostor, BOOL match, LONGLONG timestamp);
 static void windivert_queue_packet(context_t context, packet_t packet);
-static NTSTATUS windivert_inject_packet(packet_t packet);
+static void windivert_reinject_packet(packet_t packet);
 static void windivert_free_packet(packet_t packet);
 static BOOL windivert_copy_data(PNET_BUFFER buffer, PVOID data, UINT size);
 static BOOL windivert_get_data(PNET_BUFFER buffer, UINT length, INT min,
@@ -1981,17 +1979,20 @@ windivert_cleanup_error:
     context->state = WINDIVERT_CONTEXT_STATE_CLOSING;
     sniff_mode = ((context->flags & WINDIVERT_FLAG_SNIFF) != 0);
     forward = (context->layer == WINDIVERT_LAYER_NETWORK_FORWARD);
-    while (!IsListEmpty(&context->flow_set))
+    entry = context->flow_set.Flink;
+    if (entry != &context->flow_set)
     {
-        entry = RemoveHeadList(&context->flow_set);
-        flow = CONTAINING_RECORD(entry, struct flow_s, entry);
-        flow->deleted = TRUE;
         KeReleaseInStackQueuedSpinLock(&lock_handle);
-        status = FwpsFlowRemoveContext0(flow->flow_id, flow->layer_id,
-            flow->callout_id);
-        if (!NT_SUCCESS(status))
+        for (; entry != &context->flow_set; entry = entry->Flink)
         {
-            windivert_free(flow);
+            flow = CONTAINING_RECORD(entry, struct flow_s, entry);
+            status = FwpsFlowRemoveContext0(flow->flow_id, flow->layer_id,
+                flow->callout_id);
+            if (!NT_SUCCESS(status) && status != STATUS_UNSUCCESSFUL)
+            {
+                // For STATUS_UNSUCCESSFUL, flow_delete() is still called.
+                WdfObjectDereference((WDFOBJECT)object);
+            }
         }
         KeAcquireInStackQueuedSpinLock(&context->lock, &lock_handle);
     }
@@ -2005,7 +2006,7 @@ windivert_cleanup_error:
         timeout = WINDIVERT_TIMEOUT(context, packet->timestamp, timestamp);
         if (!sniff_mode && !timeout)
         {
-            windivert_inject_packet(packet);
+            windivert_reinject_packet(packet);
         }
         else
         {
@@ -2027,7 +2028,7 @@ windivert_cleanup_error:
         timeout = WINDIVERT_TIMEOUT(context, work->timestamp, timestamp);
         if (!sniff_mode && !timeout)
         {
-            windivert_inject_packet(work);
+            windivert_reinject_packet(work);
         }
         else
         {
@@ -2086,6 +2087,8 @@ extern VOID windivert_destroy(IN WDFOBJECT object)
     KLOCK_QUEUE_HANDLE lock_handle;
     context_t context = windivert_context_get((WDFFILEOBJECT)object);
     const WINDIVERT_FILTER *filter;
+    PLIST_ENTRY entry;
+    flow_t flow;
     NTSTATUS status;
 
     DEBUG("DESTROY: destroying WinDivert context (context=%p)", context);
@@ -2106,6 +2109,12 @@ extern VOID windivert_destroy(IN WDFOBJECT object)
         FwpmEngineClose0(context->engine_handle);
     }
     windivert_free((PVOID)filter);
+    while (!IsListEmpty(&context->flow_set))
+    {
+        entry = RemoveHeadList(&context->flow_set);
+        flow = CONTAINING_RECORD(entry, struct flow_s, entry);
+        windivert_free(flow);
+    }
     if (context->process != NULL)
     {
         ObDereferenceObject(context->process);
@@ -2590,20 +2599,19 @@ static NTSTATUS windivert_write(context_t context, WDFREQUEST request,
     req_context_t req_context)
 {
     KLOCK_QUEUE_HANDLE lock_handle;
-    PMDL mdl = NULL;
-    PVOID data, data_copy;
-    packet_t packet;
-    UINT data_len, packet_len, packet_size, inject_len;
-    PWINDIVERT_DATA_NETWORK network_data;
+    PMDL mdl = NULL, mdl_copy = NULL;
+    PVOID data, data_copy = NULL;
+    UINT data_len, packet_len, inject_len;
     PWINDIVERT_IPHDR ip_header;
     PWINDIVERT_IPV6HDR ipv6_header;
+    BOOL ipv4;
     UINT8 layer;
     UINT32 priority;
     UINT64 flags, checksums;
     HANDLE handle;
     PNET_BUFFER_LIST buffers = NULL;
     PWINDIVERT_ADDRESS addr;
-    UINT i, addr_len, addr_len_max, version;
+    UINT i, addr_len, addr_len_max;
     NTSTATUS status = STATUS_SUCCESS, status_soft_error = STATUS_SUCCESS;
 
     DEBUG("WRITE: writing/injecting a packet (context=%p, request=%p)",
@@ -2672,6 +2680,10 @@ static NTSTATUS windivert_write(context_t context, WDFREQUEST request,
             i < WINDIVERT_BATCH_MAX;
             i++, addr_len += sizeof(WINDIVERT_ADDRESS))
     {
+        buffers   = NULL;
+        mdl_copy  = NULL;
+        data_copy = NULL;
+        
         // Get the packet length:
         if (data_len < sizeof(WINDIVERT_IPHDR))
         {
@@ -2681,15 +2693,11 @@ windivert_write_too_small_packet:
             goto windivert_write_hard_error;
         }
         ip_header = (PWINDIVERT_IPHDR)data;
-        version = ip_header->Version;
-        switch (version)
+        switch (ip_header->Version)
         {
             case 4:
                 packet_len = RtlUshortByteSwap(ip_header->Length);
-                if (packet_len < sizeof(WINDIVERT_IPHDR))
-                {
-                    goto windivert_write_invalid_packet;
-                }
+                ipv4 = TRUE;
                 break;
             case 6:
                 if (data_len < sizeof(WINDIVERT_IPV6HDR))
@@ -2699,11 +2707,11 @@ windivert_write_too_small_packet:
                 ipv6_header = (PWINDIVERT_IPV6HDR)data;
                 packet_len = RtlUshortByteSwap(ipv6_header->Length) +
                     sizeof(WINDIVERT_IPV6HDR);
+                ipv4 = FALSE;
                 break;
             default:
-windivert_write_invalid_packet:
                 status = STATUS_INVALID_PARAMETER;
-                DEBUG_ERROR("failed to inject invalid packet", status);
+                DEBUG_ERROR("failed to inject non-IP packet", status);
                 goto windivert_write_hard_error;
         }
         if (data_len < packet_len)
@@ -2711,77 +2719,100 @@ windivert_write_invalid_packet:
             goto windivert_write_too_small_packet;
         }
 
-        // Copy packet & data:
-        packet_size = WINDIVERT_PACKET_SIZE(WINDIVERT_DATA_NETWORK,
-            packet_len);
-        packet = (packet_t)windivert_malloc(packet_size, FALSE);
-        if (packet == NULL)
+        // Copy packet data:
+        data_copy = windivert_malloc(packet_len, FALSE);
+        if (data_copy == NULL)
         {
             status = STATUS_INSUFFICIENT_RESOURCES;
-            DEBUG_ERROR("failed to allocate memory for injected packet",
+            DEBUG_ERROR("failed to allocate memory for injected packet data",
                 status);
             goto windivert_write_hard_error;
         }
-        packet->layer         = layer;
-        packet->event         = WINDIVERT_EVENT_NETWORK_PACKET;
-        packet->sniffed       = 0;      // Unused
-        packet->outbound      = addr[i].Outbound;
-        packet->loopback      = 0;      // Unused
-        packet->impostor      = addr[i].Impostor;
-        packet->ipv6          = (version == 6? 1: 0);
-        packet->ip_checksum   = addr[i].IPChecksum;
-        packet->tcp_checksum  = addr[i].TCPChecksum;
-        packet->udp_checksum  = addr[i].UDPChecksum;
-        packet->icmp_checksum = 1;      // Assumed valid
-        packet->match         = 0;      // Unused
-        packet->packet_size   = packet_size;
-        packet->packet_len    = packet_len;
-        packet->priority      = priority;
-        packet->timestamp     = 0;      // Unused
-        packet->object        = NULL;
-        network_data =
-            (PWINDIVERT_DATA_NETWORK)WINDIVERT_LAYER_DATA_PTR(packet);
-        RtlCopyMemory(network_data, &addr[i].Network, sizeof(network_data));
-        data_copy = WINDIVERT_PACKET_DATA_PTR(WINDIVERT_DATA_NETWORK, packet);
         RtlCopyMemory(data_copy, data, packet_len);
-        switch (version)
-        {
-            case 4:
-                ip_header = (PWINDIVERT_IPHDR)data_copy;
-                if (ip_header->Version != 4 ||
-                        packet_len != RtlUshortByteSwap(ip_header->Length))
-                {
-                    windivert_free(packet);
-                    goto windivert_write_invalid_packet;
-                }
-                break;
-            case 6:
-                ipv6_header = (PWINDIVERT_IPV6HDR)data_copy;
-                if (ipv6_header->Version != 6 ||
-                        packet_len != RtlUshortByteSwap(ipv6_header->Length) +
-                            sizeof(WINDIVERT_IPV6HDR))
-                {
-                    windivert_free(packet);
-                    goto windivert_write_invalid_packet;
-                }
-                break;
-        }
 
         // Check bounds:
         DEBUG_BOUNDS_CHECK((PVOID)addr, (UINT8 *)addr + addr_len_max,
             (PVOID)&addr[i], (PVOID)&addr[i+1]);
 
-        // Inject packet:
-        status = windivert_inject_packet(packet);
+        // Fix checksums:
+        if (addr[i].IPChecksum == 0 || addr[i].TCPChecksum == 0 ||
+            addr[i].UDPChecksum == 0)
+        {
+            checksums = 
+                (addr[i].IPChecksum == 0?  0:
+                    WINDIVERT_HELPER_NO_IP_CHECKSUM) |
+                (addr[i].TCPChecksum == 0? 0:
+                    WINDIVERT_HELPER_NO_TCP_CHECKSUM) |
+                (addr[i].UDPChecksum == 0? 0:
+                    WINDIVERT_HELPER_NO_UDP_CHECKSUM) |
+                WINDIVERT_HELPER_NO_ICMP_CHECKSUM |
+                WINDIVERT_HELPER_NO_ICMPV6_CHECKSUM;
+            WinDivertHelperCalcChecksums(data_copy, packet_len, NULL,
+                checksums);
+        }
+
+        // Decrement TTL for impostor packets:
+        if (addr[i].Impostor &&
+                !WinDivertHelperDecrementTTL(data_copy, packet_len))
+        {
+            status_soft_error = STATUS_HOPLIMIT_EXCEEDED;
+            windivert_free(data_copy);
+            goto windivert_write_loop;
+        }
+
+        // Allocate packet:
+        mdl_copy = IoAllocateMdl(data_copy, packet_len, FALSE, FALSE, NULL);
+        if (mdl_copy == NULL)
+        {
+            status = STATUS_INSUFFICIENT_RESOURCES;
+            DEBUG_ERROR("failed to allocate MDL for injected packet", status);
+            goto windivert_write_hard_error;
+        }
+        MmBuildMdlForNonPagedPool(mdl_copy);
+        status = FwpsAllocateNetBufferAndNetBufferList0(nbl_pool_handle, 0, 0,
+            mdl_copy, 0, packet_len, &buffers);
         if (!NT_SUCCESS(status))
         {
-            if (status == STATUS_INSUFFICIENT_RESOURCES)
-            {
-                goto windivert_write_hard_error;
-            }
-            status_soft_error = status;
+            DEBUG_ERROR("failed to create NET_BUFFER_LIST for injected packet",
+                status);
+            goto windivert_write_hard_error;
         }
 
+        // Inject packet:
+        if (layer == WINDIVERT_LAYER_NETWORK_FORWARD)
+        {
+            handle = (ipv4? inject_handle_forward: injectv6_handle_forward);
+            status = FwpsInjectForwardAsync0(handle, (HANDLE)priority, 0,
+                (ipv4? AF_INET: AF_INET6), UNSPECIFIED_COMPARTMENT_ID,
+                addr[i].Network.IfIdx, buffers, windivert_inject_complete,
+                data_copy);
+        }
+        else if (addr[i].Outbound != 0)
+        {
+            handle = (ipv4? inject_handle_out: injectv6_handle_out);
+            status = FwpsInjectNetworkSendAsync0(handle, (HANDLE)priority, 0,
+                UNSPECIFIED_COMPARTMENT_ID, buffers, windivert_inject_complete,
+                data_copy);
+        }
+        else
+        {
+            handle = (ipv4? inject_handle_in: injectv6_handle_in);
+            status = FwpsInjectNetworkReceiveAsync0(handle, (HANDLE)priority, 0,
+                UNSPECIFIED_COMPARTMENT_ID, addr[i].Network.IfIdx,
+                addr[i].Network.SubIfIdx, buffers, windivert_inject_complete,
+                data_copy);
+        }
+
+        if (!NT_SUCCESS(status))
+        {
+            status_soft_error = status;
+            FwpsFreeNetBufferList0(buffers);
+            IoFreeMdl(mdl_copy);
+            windivert_free(data_copy);
+        }
+
+windivert_write_loop:
+
         // Reset state:
         inject_len += packet_len;
         data        = (PVOID)((UINT8 *)data + packet_len);
@@ -2796,9 +2827,54 @@ windivert_write_invalid_packet:
 windivert_write_hard_error:
 
     // Request to be completed in windivert_ioctl()
+    if (buffers != NULL)
+    {
+        FwpsFreeNetBufferList0(buffers);
+    }
+    if (mdl_copy != NULL)
+    {
+        IoFreeMdl(mdl_copy);
+    }
+    windivert_free(data_copy);
+
     return status;
 }
 
+/*
+ * WinDivert inject complete routine.
+ */
+static void NTAPI windivert_inject_complete(VOID *data,
+    NET_BUFFER_LIST *buffers, BOOLEAN dispatch_level)
+{
+    PMDL mdl;
+    PNET_BUFFER buffer;
+    UNREFERENCED_PARAMETER(dispatch_level);
+
+    buffer = NET_BUFFER_LIST_FIRST_NB(buffers);
+    mdl = NET_BUFFER_FIRST_MDL(buffer);
+    windivert_free(data);
+    IoFreeMdl(mdl);
+    FwpsFreeNetBufferList0(buffers);
+}
+
+/*
+ * WinDivert reinject complete routine.
+ */
+static void NTAPI windivert_reinject_complete(VOID *context,
+    NET_BUFFER_LIST *buffers, BOOLEAN dispatch_level)
+{
+    PMDL mdl;
+    PNET_BUFFER buffer;
+    packet_t packet;
+    UNREFERENCED_PARAMETER(dispatch_level);
+
+    buffer = NET_BUFFER_LIST_FIRST_NB(buffers);
+    packet = (packet_t)context;
+    mdl = NET_BUFFER_FIRST_MDL(buffer);
+    windivert_free_packet(packet);
+    IoFreeMdl(mdl);
+    FwpsFreeNetBufferList0(buffers);
+}
 
 /*
  * WinDivert caller context preprocessing.
@@ -4112,22 +4188,11 @@ static void windivert_flow_established_classify(context_t context,
     flow->flow_id = flow_id;
     flow->callout_id = callout_id;
     flow->layer_id = layer_id;
-    flow->inserted = FALSE;
-    flow->deleted = FALSE;
     flow->outbound = outbound;
     flow->loopback = loopback;
     flow->ipv6 = !ipv4;
     RtlCopyMemory(&flow->data, flow_data, sizeof(flow->data));
 
-    status = FwpsFlowAssociateContext0(flow_id, layer_id, callout_id,
-        (UINT64)flow);
-    if (!NT_SUCCESS(status))
-    {
-        windivert_free(flow);
-        WdfObjectDereference(object);
-        return;
-    }
-
     KeAcquireInStackQueuedSpinLock(&context->lock, &lock_handle);
     if (context->state != WINDIVERT_CONTEXT_STATE_OPEN ||
         context->shutdown_recv)
@@ -4137,19 +4202,16 @@ static void windivert_flow_established_classify(context_t context,
         WdfObjectDereference(object);
         return;
     }
-    if (!flow->deleted)
+    status = FwpsFlowAssociateContext0(flow_id, layer_id, callout_id,
+        (UINT64)flow);
+    if (!NT_SUCCESS(status))
     {
-        InsertTailList(&context->flow_set, &flow->entry);
-        flow->inserted = TRUE;
-    }
-    else
-    {
-        // Flow was deleted before insertion; we are responsible for cleanup.
         KeReleaseInStackQueuedSpinLock(&lock_handle);
         windivert_free(flow);
         WdfObjectDereference(object);
         return;
     }
+    InsertTailList(&context->flow_set, &flow->entry);
     KeReleaseInStackQueuedSpinLock(&lock_handle);
 }
 
@@ -4176,18 +4238,16 @@ static void windivert_flow_delete_notify(UINT16 layer_id, UINT32 callout_id,
     {
         return;
     }
-
     timestamp = KeQueryPerformanceCounter(NULL).QuadPart;
     context = flow->context;
 
     KeAcquireInStackQueuedSpinLock(&context->lock, &lock_handle);
     object = (WDFOBJECT)context->object; // referenced in flow_established.
-    if (flow->inserted && !flow->deleted)
+    cleanup = (context->state == WINDIVERT_CONTEXT_STATE_OPEN);
+    if (cleanup)
     {
         RemoveEntryList(&flow->entry);
     }
-    flow->deleted = TRUE;
-    cleanup = flow->inserted;
     if (context->state != WINDIVERT_CONTEXT_STATE_OPEN ||
         context->shutdown_recv)
     {
@@ -4212,12 +4272,12 @@ static void windivert_flow_delete_notify(UINT16 layer_id, UINT32 callout_id,
     }
 
 windivert_flow_delete_notify_exit:
-
     if (cleanup)
     {
+        // If context->state != OPEN, then destroy() will free the flow.
         windivert_free(flow);
-        WdfObjectDereference(object);
     }
+    WdfObjectDereference(object);
 }
 
 /*
@@ -4844,7 +4904,7 @@ VOID windivert_worker(IN WDFWORKITEM item)
         }
         else
         {
-            windivert_inject_packet(work);
+            windivert_reinject_packet(work);
         }
 
         KeAcquireInStackQueuedSpinLock(&context->lock, &lock_handle);
@@ -5005,22 +5065,21 @@ static BOOL windivert_queue_work(context_t context, PVOID packet,
             return TRUE;
     }
 
-    work->layer         = layer;
-    work->event         = event;
-    work->sniffed       = (sniffed? 1: 0);
-    work->outbound      = (outbound? 1: 0);
-    work->loopback      = (loopback? 1: 0);
-    work->impostor      = (impostor? 1: 0);
-    work->ipv6          = (!ipv4? 1: 0);
-    work->ip_checksum   = (ip_checksum? 1: 0);
-    work->tcp_checksum  = (tcp_checksum? 1: 0);
-    work->udp_checksum  = (udp_checksum? 1: 0);
-    work->icmp_checksum = 1;
-    work->match         = match;
-    work->packet_size   = packet_size;
-    work->priority      = priority;
-    work->timestamp     = timestamp;
-    work->object        = object;
+    work->layer        = layer;
+    work->event        = event;
+    work->sniffed      = (sniffed? 1: 0);
+    work->outbound     = (outbound? 1: 0);
+    work->loopback     = (loopback? 1: 0);
+    work->impostor     = (impostor? 1: 0);
+    work->ipv6         = (!ipv4? 1: 0);
+    work->ip_checksum  = (ip_checksum? 1: 0);
+    work->tcp_checksum = (tcp_checksum? 1: 0);
+    work->udp_checksum = (udp_checksum? 1: 0);
+    work->match        = match;
+    work->packet_size  = packet_size;
+    work->priority     = priority;
+    work->timestamp    = timestamp;
+    work->object       = object;
     if (object != NULL)
     {
         ObfReferenceObject(object);
@@ -5082,7 +5141,7 @@ static void windivert_queue_packet(context_t context, packet_t packet)
         if (context->state != WINDIVERT_CONTEXT_STATE_OPEN)
         {
             KeReleaseInStackQueuedSpinLock(&lock_handle);
-            windivert_inject_packet(packet);
+            windivert_reinject_packet(packet);
             return;
         }
         if (packet->packet_size > context->packet_queue_maxsize)
@@ -5134,9 +5193,9 @@ static void windivert_queue_packet(context_t context, packet_t packet)
 }
 
 /*
- * Inject a packet.
+ * Re-inject a packet.
  */
-static NTSTATUS windivert_inject_packet(packet_t packet)
+static void windivert_reinject_packet(packet_t packet)
 {
     UINT8 *packet_data;
     UINT32 packet_len;
@@ -5152,7 +5211,7 @@ static NTSTATUS windivert_inject_packet(packet_t packet)
         packet->layer != WINDIVERT_LAYER_NETWORK_FORWARD)
     {
         windivert_free_packet(packet);
-        return STATUS_INVALID_PARAMETER;
+        return;
     }
 
     network_data = (PWINDIVERT_DATA_NETWORK)WINDIVERT_LAYER_DATA_PTR(packet);
@@ -5160,43 +5219,47 @@ static NTSTATUS windivert_inject_packet(packet_t packet)
     packet_len = packet->packet_len;
 
     // Fix checksums:
-    checksums =
-        (packet->ip_checksum == 0?   0: WINDIVERT_HELPER_NO_IP_CHECKSUM) |
-        (packet->tcp_checksum == 0?  0: WINDIVERT_HELPER_NO_TCP_CHECKSUM) |
-        (packet->udp_checksum == 0?  0: WINDIVERT_HELPER_NO_UDP_CHECKSUM) |
-        (packet->icmp_checksum == 0? 0: WINDIVERT_HELPER_NO_ICMP_CHECKSUM |
-                                        WINDIVERT_HELPER_NO_ICMPV6_CHECKSUM);
-    WinDivertHelperCalcChecksums(packet_data, packet_len, NULL, checksums);
+    if (packet->ip_checksum == 0 || packet->tcp_checksum == 0 ||
+        packet->udp_checksum == 0)
+    {
+        checksums =
+            (packet->ip_checksum == 0?  0: WINDIVERT_HELPER_NO_IP_CHECKSUM) |
+            (packet->tcp_checksum == 0? 0: WINDIVERT_HELPER_NO_TCP_CHECKSUM) |
+            (packet->udp_checksum == 0? 0: WINDIVERT_HELPER_NO_UDP_CHECKSUM) |
+            WINDIVERT_HELPER_NO_ICMP_CHECKSUM |
+            WINDIVERT_HELPER_NO_ICMPV6_CHECKSUM;
+        WinDivertHelperCalcChecksums(packet_data, packet_len, NULL, checksums);
+    }
 
     // Decrement TTL for impostor packets:
     if (packet->impostor != 0 &&
             !WinDivertHelperDecrementTTL(packet_data, packet_len))
     {
         status = STATUS_HOPLIMIT_EXCEEDED;
-        DEBUG_ERROR("failed to inject ttl-exceeded impostor packet", status);
+        DEBUG_ERROR("failed to reinject ttl-exceeded impostor packet", status);
         windivert_free_packet(packet);
-        return status;
+        return;
     }
 
-    // Inject packet:
+    // Reinject packet:
     mdl = IoAllocateMdl(packet_data, packet_len, FALSE, FALSE, NULL);
     if (mdl == NULL)
     {
         status = STATUS_INSUFFICIENT_RESOURCES;
-        DEBUG_ERROR("failed to allocate MDL for injected packet", status);
+        DEBUG_ERROR("failed to allocate MDL for reinjected packet", status);
         windivert_free_packet(packet);
-        return status;
+        return;
     }
     MmBuildMdlForNonPagedPool(mdl);
     status = FwpsAllocateNetBufferAndNetBufferList0(nbl_pool_handle, 0, 0,
         mdl, 0, packet_len, &buffers);
     if (!NT_SUCCESS(status))
     {
-        DEBUG_ERROR("failed to create NET_BUFFER_LIST for injected packet",
+        DEBUG_ERROR("failed to create NET_BUFFER_LIST for reinjected packet",
             status);
         IoFreeMdl(mdl);
         windivert_free_packet(packet);
-        return status;
+        return;
     }
     priority = packet->priority;
     if (packet->layer == WINDIVERT_LAYER_NETWORK_FORWARD)
@@ -5204,14 +5267,14 @@ static NTSTATUS windivert_inject_packet(packet_t packet)
         handle = (packet->ipv6? injectv6_handle_forward: inject_handle_forward);
         status = FwpsInjectForwardAsync0(handle, (HANDLE)priority, 0,
             (packet->ipv6? AF_INET6: AF_INET), UNSPECIFIED_COMPARTMENT_ID,
-            network_data->IfIdx, buffers, windivert_inject_complete,
+            network_data->IfIdx, buffers, windivert_reinject_complete, 
             (HANDLE)packet);
     }
     else if (packet->outbound)
     {
         handle = (packet->ipv6? injectv6_handle_out: inject_handle_out);
         status = FwpsInjectNetworkSendAsync0(handle, (HANDLE)priority, 0,
-            UNSPECIFIED_COMPARTMENT_ID, buffers, windivert_inject_complete,
+            UNSPECIFIED_COMPARTMENT_ID, buffers, windivert_reinject_complete,
             (HANDLE)packet);
     }
     else
@@ -5219,18 +5282,17 @@ static NTSTATUS windivert_inject_packet(packet_t packet)
         handle = (packet->ipv6? injectv6_handle_in: inject_handle_in);
         status = FwpsInjectNetworkReceiveAsync0(handle, (HANDLE)priority, 0,
             UNSPECIFIED_COMPARTMENT_ID, network_data->IfIdx,
-            network_data->SubIfIdx, buffers, windivert_inject_complete,
+            network_data->SubIfIdx, buffers, windivert_reinject_complete,
             (HANDLE)packet);
     }
 
     if (!NT_SUCCESS(status))
     {
-        DEBUG_ERROR("failed to inject (packet=%p)", status, packet);
+        DEBUG_ERROR("failed to reinject (packet=%p)", status, packet);
         FwpsFreeNetBufferList0(buffers);
         IoFreeMdl(mdl);
         windivert_free_packet(packet);
     }
-    return status;
 }
 
 /*
@@ -5245,172 +5307,6 @@ static void windivert_free_packet(packet_t packet)
     windivert_free(packet);
 }
 
-/*
- * WinDivert inject complete routine.
- */
-static void NTAPI windivert_inject_complete(VOID *context,
-    NET_BUFFER_LIST *buffers, BOOLEAN dispatch_level)
-{
-    PMDL mdl;
-    PNET_BUFFER buffer;
-    packet_t packet;
-    UNREFERENCED_PARAMETER(dispatch_level);
-
-    packet = (packet_t)context;
-    if (buffers->Status == STATUS_INVALID_BUFFER_SIZE)
-    {
-        // STATUS_INVALID_BUFFER_SIZE indicates that the send failed because
-        // the packet was larger than the MTU.  We generate an ICMP
-        // Fragmentation Needed (for IPv4) or an ICMPV6 Packet Too Big (for
-        // IPv6) message to allow for PMTU discovery.
-        windivert_inject_packet_too_big(packet);
-    }
-
-    buffer = NET_BUFFER_LIST_FIRST_NB(buffers);
-    mdl = NET_BUFFER_FIRST_MDL(buffer);
-    IoFreeMdl(mdl);
-    FwpsFreeNetBufferList0(buffers);
-    windivert_free_packet(packet);
-}
-
-/*
- * WinDivert inject an ICMP(V6) Packet Too Big message.
- */
-static void windivert_inject_packet_too_big(packet_t packet)
-{
-    const UINT mtus[] =
-    {
-        568, 768, 1024, 1192, 1280, 1372, 1452, 1500, 4096, UINT16_MAX,
-            UINT32_MAX
-    };
-    PWINDIVERT_IPHDR ip_header, ip_header_2;
-    PWINDIVERT_IPV6HDR ipv6_header, ipv6_header_2;
-    PWINDIVERT_ICMPHDR icmp_header;
-    PWINDIVERT_ICMPV6HDR icmpv6_header;
-    packet_t icmp;
-    UINT version, packet_len, copy_len, icmp_len;
-    UINT icmp_size;
-    UINT i, min_mtu = /*ipv4 min MTU=*/568, mtu;
-    UINT32 flowlabel;
-    UINT8 *data;
-
-    if (packet->layer != WINDIVERT_LAYER_NETWORK || !packet->outbound ||
-            packet->loopback)
-    {
-        return;
-    }
-    ip_header = (PWINDIVERT_IPHDR)WINDIVERT_PACKET_DATA_PTR(
-        WINDIVERT_DATA_NETWORK, packet);
-    version = ip_header->Version;
-    switch (version)
-    {
-        case 4:
-            packet_len = RtlUshortByteSwap(ip_header->Length);
-            copy_len = ip_header->HdrLength * sizeof(UINT32) + 8;
-            copy_len = (packet_len < copy_len? packet_len: copy_len);
-            icmp_len = sizeof(WINDIVERT_IPHDR) + sizeof(WINDIVERT_ICMPHDR) +
-                copy_len;
-            break;
-        case 6:
-            ipv6_header = (PWINDIVERT_IPV6HDR)ip_header;
-            packet_len = RtlUshortByteSwap(ipv6_header->Length) +
-                sizeof(WINDIVERT_IPV6HDR);
-            min_mtu = /*ipv6 min MTU=*/1280;
-            copy_len = min_mtu - sizeof(WINDIVERT_IPV6HDR) -
-                sizeof(WINDIVERT_ICMPV6HDR);
-            copy_len = (packet_len < copy_len? packet_len: copy_len);
-            icmp_len = sizeof(WINDIVERT_IPV6HDR) +
-                sizeof(WINDIVERT_ICMPV6HDR) + copy_len;
-            break;
-        default:
-            return;
-    }
-    if (packet_len <= min_mtu)
-    {
-        return;
-    }
-
-    // We do not actually know the MTU value, so we make an educated guess.
-    for (i = 0; packet_len > mtus[i]; i++)
-        ;
-    mtu = (i == 0? min_mtu: mtus[i-1]);
-    mtu = (mtu < min_mtu? min_mtu: mtu);
-
-    icmp_size = WINDIVERT_PACKET_SIZE(WINDIVERT_DATA_NETWORK, icmp_len);
-    icmp = (packet_t)windivert_malloc(icmp_size, FALSE);
-    if (icmp == NULL)
-    {
-        return;
-    }
-    icmp->layer         = WINDIVERT_LAYER_NETWORK;
-    icmp->event         = WINDIVERT_EVENT_NETWORK_PACKET;
-    icmp->sniffed       = 0;        // Unused
-    icmp->outbound      = 0;        // Inbound
-    icmp->loopback      = 0;        // Unused
-    icmp->impostor      = 0;        // Treat as non-impostor
-    icmp->ipv6          = (version == 6? 1: 0);
-    icmp->ip_checksum   = 0;        // IP checksum valid
-    icmp->tcp_checksum  = 0;        // Unused
-    icmp->udp_checksum  = 0;        // Unused
-    icmp->icmp_checksum = 0;        // ICMP(V6) checksum invalid
-    icmp->match         = 0;        // Unused
-    icmp->packet_size   = icmp_size;
-    icmp->packet_len    = icmp_len;
-    icmp->priority      = packet->priority;
-    icmp->timestamp     = 0;        // Unused
-    icmp->object        = NULL;
-    RtlCopyMemory(WINDIVERT_LAYER_DATA_PTR(icmp),
-        WINDIVERT_LAYER_DATA_PTR(packet), sizeof(WINDIVERT_DATA_NETWORK));
-    data = WINDIVERT_PACKET_DATA_PTR(WINDIVERT_DATA_NETWORK, icmp);
-    switch (version)
-    {
-        case 4:
-            ip_header_2 = (PWINDIVERT_IPHDR)data;
-            ip_header_2->Version   = 4;
-            ip_header_2->HdrLength = sizeof(WINDIVERT_IPHDR) / sizeof(UINT32);
-            ip_header_2->TOS       = 0x0;
-            ip_header_2->Length    = RtlUshortByteSwap(icmp_len);
-            ip_header_2->Id        = 0x0;
-            ip_header_2->TTL       = 64;
-            ip_header_2->Protocol  = IPPROTO_ICMP;
-            ip_header_2->SrcAddr   = ip_header->DstAddr;
-            ip_header_2->DstAddr   = ip_header->SrcAddr;
-            WINDIVERT_IPHDR_SET_FRAGOFF(ip_header_2, 0x0);
-            WINDIVERT_IPHDR_SET_MF(ip_header_2, 0);
-            WINDIVERT_IPHDR_SET_DF(ip_header_2, 1);
-            WINDIVERT_IPHDR_SET_RESERVED(ip_header_2, 0x0);
-            icmp_header = (PWINDIVERT_ICMPHDR)(ip_header_2 + 1);
-            icmp_header->Type      = /*Destination Unreachable=*/3;
-            icmp_header->Code      = /*Fragmentation required=*/4;
-            icmp_header->Body      = ((UINT32)RtlUshortByteSwap(mtu)) << 16;
-            data = (UINT8 *)(icmp_header + 1);
-            RtlCopyMemory(data, ip_header, copy_len);
-            break;
-        case 6:
-            icmp_len -= sizeof(WINDIVERT_IPV6HDR);
-            ipv6_header_2 = (PWINDIVERT_IPV6HDR)data;
-            ipv6_header_2->Version  = 6;
-            ipv6_header_2->Length   = RtlUshortByteSwap(icmp_len);
-            ipv6_header_2->NextHdr  = IPPROTO_ICMPV6;
-            ipv6_header_2->HopLimit = 64;
-            RtlCopyMemory(ipv6_header_2->SrcAddr, ipv6_header->DstAddr,
-                sizeof(ipv6_header_2->SrcAddr));
-            RtlCopyMemory(ipv6_header_2->DstAddr, ipv6_header->SrcAddr,
-                sizeof(ipv6_header_2->DstAddr));
-            WINDIVERT_IPV6HDR_SET_TRAFFICCLASS(ipv6_header_2, 0x0);
-            flowlabel = WINDIVERT_IPV6HDR_GET_FLOWLABEL(ipv6_header);
-            WINDIVERT_IPV6HDR_SET_FLOWLABEL(ipv6_header_2, flowlabel);
-            icmpv6_header = (PWINDIVERT_ICMPV6HDR)(ipv6_header_2 + 1);
-            icmpv6_header->Type = /*Packet Too Big=*/2;
-            icmpv6_header->Code = 0;
-            icmpv6_header->Body = RtlUlongByteSwap(mtu);
-            data = (UINT8 *)(icmpv6_header + 1);
-            RtlCopyMemory(data, ipv6_header, copy_len);
-            break;
-    }
-    windivert_inject_packet(icmp);
-}
-
 /*
  * Copy data from a NET_BUFFER.
  */

sys/windivert.rc

@@ -1,6 +1,6 @@
 /*
  * windivert.rc
- * (C) 2019, all rights reserved,
+ * (C) 2022, all rights reserved,
  *
  * This file is part of WinDivert.
  *
@@ -48,7 +48,7 @@
 #define VER_PRODUCTVERSION          2.2
 #define VER_PRODUCTVERSION_STR      "2.2"
 #define VER_COMPANYNAME_STR         "Basil"
-#define VER_LEGALCOPYRIGHT_YEARS    "2011-2019"
+#define VER_LEGALCOPYRIGHT_YEARS    "2011-2022"
 #define VER_LEGALCOPYRIGHT_STR      \
     "Copyright \251 " VER_COMPANYNAME_STR " " VER_LEGALCOPYRIGHT_YEARS 
 #define VER_FILEVERSION             VER_PRODUCTVERSION