/*
* windivert.c
* (C) 2017, all rights reserved,
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program. If not, see .
*/
#include
#include
#include
#include
#include
#include
#define INITGUID
#include
#include "windivert_device.h"
/*
* WDK function declaration cruft.
*/
DRIVER_INITIALIZE DriverEntry;
EVT_WDF_DRIVER_UNLOAD windivert_unload;
EVT_WDF_IO_IN_CALLER_CONTEXT windivert_caller_context;
EVT_WDF_IO_QUEUE_IO_DEVICE_CONTROL windivert_ioctl;
EVT_WDF_DEVICE_FILE_CREATE windivert_create;
EVT_WDF_FILE_CLEANUP windivert_cleanup;
EVT_WDF_FILE_CLOSE windivert_close;
EVT_WDF_OBJECT_CONTEXT_DESTROY windivert_destroy;
EVT_WDF_WORKITEM windivert_worker;
/*
* Debugging macros.
*/
// #define DEBUG_ON
#define DEBUG_BUFSIZE 256
#ifdef DEBUG_ON
static void DEBUG(PCCH format, ...)
{
va_list args;
char buf[DEBUG_BUFSIZE+1];
if (KeGetCurrentIrql() != PASSIVE_LEVEL)
{
return;
}
va_start(args, format);
RtlStringCbVPrintfA(buf, DEBUG_BUFSIZE, format, args);
DbgPrint("WINDIVERT: %s\n", buf);
va_end(args);
}
static void DEBUG_ERROR(PCCH format, NTSTATUS status, ...)
{
va_list args;
char buf[DEBUG_BUFSIZE+1];
if (KeGetCurrentIrql() != PASSIVE_LEVEL)
{
return;
}
va_start(args, status);
RtlStringCbVPrintfA(buf, DEBUG_BUFSIZE, format, args);
DbgPrint("WINDIVERT: *** ERROR ***: (status = %x): %s\n", status, buf);
va_end(args);
}
#else // DEBUG_ON
#define DEBUG(format, ...)
#define DEBUG_ERROR(format, status, ...)
#endif
#define WINDIVERT_TAG 'viDW'
/*
* WinDivert packet filter.
*/
struct filter_s
{
UINT8 protocol:4; // field's protocol
UINT8 test:4; // Filter test
UINT8 field; // Field of interest
UINT16 success; // Success continuation
UINT16 failure; // Fail continuation
UINT32 arg[4]; // Comparison argument
};
typedef struct filter_s *filter_t;
#define WINDIVERT_FILTER_PROTOCOL_NONE 0
#define WINDIVERT_FILTER_PROTOCOL_IP 1
#define WINDIVERT_FILTER_PROTOCOL_IPV6 2
#define WINDIVERT_FILTER_PROTOCOL_ICMP 3
#define WINDIVERT_FILTER_PROTOCOL_ICMPV6 4
#define WINDIVERT_FILTER_PROTOCOL_TCP 5
#define WINDIVERT_FILTER_PROTOCOL_UDP 6
/*
* WinDivert context information.
*/
#define WINDIVERT_CONTEXT_SIZE (sizeof(struct context_s))
#define WINDIVERT_CONTEXT_MAXLAYERS 4
#define WINDIVERT_CONTEXT_MAXWORKERS 1
#define WINDIVERT_CONTEXT_OUTBOUND_IPV4_LAYER 0
#define WINDIVERT_CONTEXT_INBOUND_IPV4_LAYER 1
#define WINDIVERT_CONTEXT_OUTBOUND_IPV6_LAYER 2
#define WINDIVERT_CONTEXT_INBOUND_IPV6_LAYER 3
typedef enum
{
WINDIVERT_CONTEXT_STATE_OPENING = 0xA0, // Context is opening.
WINDIVERT_CONTEXT_STATE_OPEN = 0xB1, // Context is open.
WINDIVERT_CONTEXT_STATE_CLOSING = 0xC2, // Context is closing.
WINDIVERT_CONTEXT_STATE_CLOSED = 0xD3, // Context is closed.
WINDIVERT_CONTEXT_STATE_INVALID = 0xE4 // Context is invalid.
} context_state_t;
struct context_s
{
context_state_t state; // Context's state.
KSPIN_LOCK lock; // Context-wide lock.
WDFDEVICE device; // Context's device.
WDFFILEOBJECT object; // Context's parent object.
LIST_ENTRY work_queue; // Work queue.
ULONG work_queue_length; // Work queue length.
LIST_ENTRY packet_queue; // Packet queue.
ULONG packet_queue_length; // Packet queue length.
ULONG packet_queue_maxlength; // Packet queue max length.
ULONG packet_queue_size; // Packet queue size (in bytes).
ULONG packet_queue_maxsize; // Packet queue max size.
ULONGLONG packet_queue_maxcounts; // Packet queue max counts.
ULONG packet_queue_maxtime; // Packet queue max time.
WDFQUEUE read_queue; // Read queue.
WDFWORKITEM workers[WINDIVERT_CONTEXT_MAXWORKERS];
// Read workers.
UINT8 worker_curr; // Current read worker.
UINT8 layer; // Context's layer.
UINT64 flags; // Context's flags.
UINT32 priority; // Context's priority.
GUID callout_guid[WINDIVERT_CONTEXT_MAXLAYERS];
// Callout GUIDs.
GUID filter_guid[WINDIVERT_CONTEXT_MAXLAYERS];
// Filter GUIDs.
BOOL installed[WINDIVERT_CONTEXT_MAXLAYERS];
// What is installed?
BOOL on; // Is filtering on?
HANDLE engine_handle; // WFP engine handle.
filter_t filter; // Packet filter.
};
typedef struct context_s context_s;
typedef struct context_s *context_t;
WDF_DECLARE_CONTEXT_TYPE_WITH_NAME(context_s, windivert_context_get);
/*
* WinDivert Layer information.
*/
typedef void (*windivert_callout_t)(
IN const FWPS_INCOMING_VALUES0 *fixed_vals,
IN const FWPS_INCOMING_METADATA_VALUES0 *meta_vals, IN OUT void *data,
const FWPS_FILTER0 *filter, IN UINT64 flow_context,
OUT FWPS_CLASSIFY_OUT0 *result);
struct layer_s
{
wchar_t *sublayer_name; // Sub-layer name.
wchar_t *sublayer_desc; // Sub-layer description.
wchar_t *callout_name; // Call-out name.
wchar_t *callout_desc; // Call-out description.
wchar_t *filter_name; // Filter name.
wchar_t *filter_desc; // Filter description.
GUID layer_guid; // WFP layer GUID.
GUID sublayer_guid; // Sub-layer GUID.
windivert_callout_t callout; // Call-out.
};
typedef struct layer_s *layer_t;
/*
* WinDivert request context.
*/
struct req_context_s
{
struct windivert_addr_s *addr; // Pointer to address structure.
};
typedef struct req_context_s req_context_s;
typedef struct req_context_s *req_context_t;
WDF_DECLARE_CONTEXT_TYPE_WITH_NAME(req_context_s, windivert_req_context_get);
/*
* WinDivert work structure.
*/
#define WINDIVERT_WORK_QUEUE_LEN_MAX 4096
struct work_s
{
LIST_ENTRY entry; // Entry for queue.
PNET_BUFFER_LIST buffers; // Packet list.
PNET_BUFFER buffer; // First matching packet.
UINT advance; // Bytes to retreat/advance.
BOOL is_ipv4; // Is IPv4?
BOOL hop; // Decrement TTL?
UINT8 checksums; // Which checksums are valid.
UINT8 direction; // Packet direction.
UINT32 if_idx; // Interface index.
UINT32 sub_if_idx; // Sub-interface index.
UINT32 priority; // WinDivert priority.
ULONGLONG timestamp; // Packet timestamp.
};
typedef struct work_s *work_t;
/*
* WinDivert packet structure.
*/
#define WINDIVERT_IP_CHECKSUM 0x01
#define WINDIVERT_TCP_CHECKSUM 0x02
#define WINDIVERT_UDP_CHECKSUM 0x04
#define WINDIVERT_ALL_CHECKSUMS \
(WINDIVERT_IP_CHECKSUM | WINDIVERT_TCP_CHECKSUM | WINDIVERT_UDP_CHECKSUM)
struct packet_s
{
LIST_ENTRY entry; // Entry for queue.
UINT8 checksums; // Which checksums are valid.
UINT8 direction; // Packet direction.
BOOL hop; // Decrement TTL?
UINT32 if_idx; // Interface index.
UINT32 sub_if_idx; // Sub-interface index.
ULONGLONG timestamp; // Packet timestamp.
size_t data_len; // Length of `data'.
char *data; // Packet data.
};
typedef struct packet_s *packet_t;
/*
* WinDivert address definition.
*/
struct windivert_addr_s
{
UINT32 IfIdx;
UINT32 SubIfIdx;
UINT8 Direction;
};
typedef struct windivert_addr_s *windivert_addr_t;
/*
* Header definitions.
*/
struct iphdr
{
UINT8 HdrLength:4;
UINT8 Version:4;
UINT8 TOS;
UINT16 Length;
UINT16 Id;
UINT16 FragOff0;
UINT8 TTL;
UINT8 Protocol;
UINT16 Checksum;
UINT32 SrcAddr;
UINT32 DstAddr;
};
struct ipv6hdr
{
UINT8 TrafficClass0:4;
UINT8 Version:4;
UINT8 FlowLabel0:4;
UINT8 TrafficClass1:4;
UINT16 FlowLabel1;
UINT16 Length;
UINT8 NextHdr;
UINT8 HopLimit;
UINT32 SrcAddr[4];
UINT32 DstAddr[4];
};
struct icmphdr
{
UINT8 Type;
UINT8 Code;
UINT16 Checksum;
UINT32 Body;
};
struct icmpv6hdr
{
UINT8 Type;
UINT8 Code;
UINT16 Checksum;
UINT32 Body;
};
struct tcphdr
{
UINT16 SrcPort;
UINT16 DstPort;
UINT32 SeqNum;
UINT32 AckNum;
UINT16 Reserved1:4;
UINT16 HdrLength:4;
UINT16 Fin:1;
UINT16 Syn:1;
UINT16 Rst:1;
UINT16 Psh:1;
UINT16 Ack:1;
UINT16 Urg:1;
UINT16 Reserved2:2;
UINT16 Window;
UINT16 Checksum;
UINT16 UrgPtr;
};
struct udphdr
{
UINT16 SrcPort;
UINT16 DstPort;
UINT16 Length;
UINT16 Checksum;
};
#define IPHDR_GET_FRAGOFF(hdr) (((hdr)->FragOff0) & 0xFF1F)
#define IPHDR_GET_MF(hdr) (((hdr)->FragOff0) & 0x0020)
#define IPHDR_GET_DF(hdr) (((hdr)->FragOff0) & 0x0040)
#define IPV6HDR_GET_TRAFFICCLASS(hdr) \
((((hdr)->TrafficClass0) << 4) | ((hdr)->TrafficClass1))
#define IPV6HDR_GET_FLOWLABEL(hdr) \
((((UINT32)(hdr)->FlowLabel0) << 16) | ((UINT32)(hdr)->FlowLabel1))
/*
* Misc.
*/
#define UINT8_MAX 0xFF
#define UINT16_MAX 0xFFFF
#define UINT32_MAX 0xFFFFFFFF
/*
* Global state.
*/
static HANDLE inject_handle = NULL;
static HANDLE injectv6_handle = NULL;
static NDIS_HANDLE nbl_pool_handle = NULL;
static NDIS_HANDLE nb_pool_handle = NULL;
static HANDLE engine_handle = NULL;
static LONG priority_counter = 0;
static ULONGLONG counts_per_ms = 0;
static POOL_TYPE non_paged_pool = NonPagedPool;
/*
* Priorities.
*/
#define WINDIVERT_CONTEXT_PRIORITY(priority0) \
windivert_context_priority(priority0)
static UINT32 windivert_context_priority(UINT32 priority0)
{
UINT16 priority1 = (UINT16)InterlockedIncrement(&priority_counter);
priority0 -= WINDIVERT_PRIORITY_MIN;
return ((priority0 << 16) | ((UINT32)priority1 & 0x0000FFFF));
}
#define WINDIVERT_FILTER_WEIGHT(priority) \
((UINT64)(UINT32_MAX - (priority)))
/*
* Prototypes.
*/
static void windivert_driver_unload(void);
extern VOID windivert_ioctl(IN WDFQUEUE queue, IN WDFREQUEST request,
IN size_t in_length, IN size_t out_len, IN ULONG code);
static NTSTATUS windivert_read(context_t context, WDFREQUEST request);
extern VOID windivert_worker(IN WDFWORKITEM item);
static void windivert_read_service(context_t context);
extern VOID windivert_create(IN WDFDEVICE device, IN WDFREQUEST request,
IN WDFFILEOBJECT object);
static NTSTATUS windivert_install_sublayer(layer_t layer);
static NTSTATUS windivert_install_callouts(context_t context, UINT8 layer,
BOOL is_inbound, BOOL is_outbound, BOOL is_ipv4, BOOL is_ipv6);
static NTSTATUS windivert_install_callout(context_t context, UINT idx,
layer_t layer);
static void windivert_uninstall_callouts(context_t context,
context_state_t state);
extern VOID windivert_cleanup(IN WDFFILEOBJECT object);
extern VOID windivert_close(IN WDFFILEOBJECT object);
extern VOID windivert_destroy(IN WDFOBJECT object);
extern NTSTATUS windivert_write(context_t context, WDFREQUEST request,
windivert_addr_t addr);
extern void NTAPI windivert_inject_complete(VOID *context,
NET_BUFFER_LIST *packets, BOOLEAN dispatch_level);
static NTSTATUS windivert_notify_callout(IN FWPS_CALLOUT_NOTIFY_TYPE type,
IN const GUID *filter_key, IN const FWPS_FILTER0 *filter);
static void windivert_classify_outbound_network_v4_callout(
IN const FWPS_INCOMING_VALUES0 *fixed_vals,
IN const FWPS_INCOMING_METADATA_VALUES0 *meta_vals, IN OUT void *data,
const FWPS_FILTER0 *filter, IN UINT64 flow_context,
OUT FWPS_CLASSIFY_OUT0 *result);
static void windivert_classify_inbound_network_v4_callout(
IN const FWPS_INCOMING_VALUES0 *fixed_vals,
IN const FWPS_INCOMING_METADATA_VALUES0 *meta_vals, IN OUT void *data,
const FWPS_FILTER0 *filter, IN UINT64 flow_context,
OUT FWPS_CLASSIFY_OUT0 *result);
static void windivert_classify_outbound_network_v6_callout(
IN const FWPS_INCOMING_VALUES0 *fixed_vals,
IN const FWPS_INCOMING_METADATA_VALUES0 *meta_vals, IN OUT void *data,
const FWPS_FILTER0 *filter, IN UINT64 flow_context,
OUT FWPS_CLASSIFY_OUT0 *result);
static void windivert_classify_inbound_network_v6_callout(
IN const FWPS_INCOMING_VALUES0 *fixed_vals,
IN const FWPS_INCOMING_METADATA_VALUES0 *meta_vals, IN OUT void *data,
const FWPS_FILTER0 *filter, IN UINT64 flow_context,
OUT FWPS_CLASSIFY_OUT0 *result);
static void windivert_classify_forward_network_v4_callout(
IN const FWPS_INCOMING_VALUES0 *fixed_vals,
IN const FWPS_INCOMING_METADATA_VALUES0 *meta_vals, IN OUT void *data,
const FWPS_FILTER0 *filter, IN UINT64 flow_context,
OUT FWPS_CLASSIFY_OUT0 *result);
static void windivert_classify_forward_network_v6_callout(
IN const FWPS_INCOMING_VALUES0 *fixed_vals,
IN const FWPS_INCOMING_METADATA_VALUES0 *meta_vals, IN OUT void *data,
const FWPS_FILTER0 *filter, IN UINT64 flow_context,
OUT FWPS_CLASSIFY_OUT0 *result);
static void windivert_classify_callout(context_t context, IN UINT8 direction,
IN UINT32 if_idx, IN UINT32 sub_if_idx, IN BOOL isipv4,
IN BOOL isloopback, IN UINT advance, IN OUT void *data,
IN UINT64 flow_context, OUT FWPS_CLASSIFY_OUT0 *result);
static BOOL windivert_queue_packet(context_t context, PNET_BUFFER buffer,
UINT8 direction, UINT32 if_idx, UINT32 sub_if_idx, BOOL hop,
UINT8 checksums, ULONGLONG timestamp);
static BOOL windivert_reinject_packet(BOOL sniff_mode, BOOL foward,
UINT8 direction, BOOL isipv4, UINT32 if_idx, UINT32 sub_if_idx,
UINT32 priority, PNET_BUFFER_LIST buffers, PNET_BUFFER buffer);
static void NTAPI windivert_reinject_complete(VOID *context,
NET_BUFFER_LIST *buffers, BOOLEAN dispatch_level);
static void NTAPI windivert_reinject_clone_complete(VOID *context,
NET_BUFFER_LIST *buffers_cpy, BOOLEAN dispatch_level);
static void windivert_free_packet(packet_t packet);
static UINT8 windivert_skip_headers(UINT8 proto, UINT8 **header, size_t *len);
static int windivert_big_num_compare(const UINT32 *a, const UINT32 *b);
static BOOL windivert_filter(PNET_BUFFER buffer, UINT32 if_idx,
UINT32 sub_if_idx, BOOL outbound, BOOL isipv4, BOOL hop, UINT8 checksums,
filter_t filter);
static NTSTATUS windivert_finalize_packet(void *header, size_t len,
BOOL hop, UINT8 checksums);
static filter_t windivert_filter_compile(windivert_ioctl_filter_t ioctl_filter,
size_t ioctl_filter_len);
static void windivert_filter_analyze(filter_t filter, BOOL *is_inbound,
BOOL *is_outbound, BOOL *ip_ipv4, BOOL *is_ipv6);
static BOOL windivert_filter_test(filter_t filter, UINT16 ip, UINT8 protocol,
UINT8 field, UINT32 arg);
/*
* WinDivert sublayer GUIDs
*/
DEFINE_GUID(WINDIVERT_SUBLAYER_INBOUND_IPV4_GUID,
0x8DB169DF, 0xFA88, 0x42FC,
0x8E, 0xB3, 0x17, 0x10, 0x5F, 0x62, 0x5B, 0x31);
DEFINE_GUID(WINDIVERT_SUBLAYER_OUTBOUND_IPV4_GUID,
0x8E9B9512, 0x6D8D, 0x4846,
0xB8, 0x85, 0x6b, 0x70, 0xc0, 0xE1, 0x15, 0x43);
DEFINE_GUID(WINDIVERT_SUBLAYER_INBOUND_IPV6_GUID,
0xC5CC9A51, 0xD4E7, 0x4D92,
0x9C, 0xF0, 0xEF, 0xC8, 0xE1, 0x84, 0x00, 0x23);
DEFINE_GUID(WINDIVERT_SUBLAYER_OUTBOUND_IPV6_GUID,
0xE4ED7583, 0x7F64, 0x4678,
0x9E, 0xCB, 0x2A, 0x05, 0x94, 0xA7, 0x53, 0x91);
DEFINE_GUID(WINDIVERT_SUBLAYER_FORWARD_IPV4_GUID,
0x33507872, 0x278D, 0x42F7,
0xBD, 0x23, 0x8A, 0x60, 0xA2, 0x6A, 0x3D, 0x44);
DEFINE_GUID(WINDIVERT_SUBLAYER_FORWARD_IPV6_GUID,
0xB51E5EB5, 0xCC2B, 0x42ED,
0x9A, 0xCD, 0x94, 0x28, 0xE4, 0x41, 0x09, 0x4A);
/*
* WinDivert supported layers.
*/
static struct layer_s layer_inbound_network_ipv4_0 =
{
L"" WINDIVERT_DEVICE_NAME L"_SubLayerInboundNetworkIPv4",
L"" WINDIVERT_DEVICE_NAME L" sublayer network (inbound IPv4)",
L"" WINDIVERT_DEVICE_NAME L"_CalloutInboundNetworkIPv4",
L"" WINDIVERT_DEVICE_NAME L" callout network (inbound IPv4)",
L"" WINDIVERT_DEVICE_NAME L"_FilterInboundNetworkIPv4",
L"" WINDIVERT_DEVICE_NAME L" filter network (inbound IPv4)",
{0},
{0},
windivert_classify_inbound_network_v4_callout,
};
static layer_t layer_inbound_network_ipv4 = &layer_inbound_network_ipv4_0;
static struct layer_s layer_outbound_network_ipv4_0 =
{
L"" WINDIVERT_DEVICE_NAME L"_SubLayerOutboundNetworkIPv4",
L"" WINDIVERT_DEVICE_NAME L" sublayer network (outbound IPv4)",
L"" WINDIVERT_DEVICE_NAME L"_CalloutOutboundNetworkIPv4",
L"" WINDIVERT_DEVICE_NAME L" callout network (outbound IPv4)",
L"" WINDIVERT_DEVICE_NAME L"_FilterOutboundNetworkIPv4",
L"" WINDIVERT_DEVICE_NAME L" filter network (outbound IPv4)",
{0},
{0},
windivert_classify_outbound_network_v4_callout,
};
static layer_t layer_outbound_network_ipv4 = &layer_outbound_network_ipv4_0;
static struct layer_s layer_inbound_network_ipv6_0 =
{
L"" WINDIVERT_DEVICE_NAME L"_SubLayerInboundNetworkIPv6",
L"" WINDIVERT_DEVICE_NAME L" sublayer network (inbound IPv6)",
L"" WINDIVERT_DEVICE_NAME L"_CalloutInboundNetworkIPv6",
L"" WINDIVERT_DEVICE_NAME L" callout network (inbound IPv6)",
L"" WINDIVERT_DEVICE_NAME L"_FilterInboundNetworkIPv6",
L"" WINDIVERT_DEVICE_NAME L" filter network (inbound IPv6)",
{0},
{0},
windivert_classify_inbound_network_v6_callout,
};
static layer_t layer_inbound_network_ipv6 = &layer_inbound_network_ipv6_0;
static struct layer_s layer_outbound_network_ipv6_0 =
{
L"" WINDIVERT_DEVICE_NAME L"_SubLayerOutboundNetworkIPv6",
L"" WINDIVERT_DEVICE_NAME L" sublayer network (outbound IPv6)",
L"" WINDIVERT_DEVICE_NAME L"_CalloutOutboundNetworkIPv6",
L"" WINDIVERT_DEVICE_NAME L" callout network (outbound IPv6)",
L"" WINDIVERT_DEVICE_NAME L"_FilterOutboundNetworkIPv6",
L"" WINDIVERT_DEVICE_NAME L" filter network (outbound IPv6)",
{0},
{0},
windivert_classify_outbound_network_v6_callout,
};
static layer_t layer_outbound_network_ipv6 = &layer_outbound_network_ipv6_0;
static struct layer_s layer_forward_network_ipv4_0 =
{
L"" WINDIVERT_DEVICE_NAME L"_SubLayerForwardNetworkIPv4",
L"" WINDIVERT_DEVICE_NAME L" sublayer network (forward IPv4)",
L"" WINDIVERT_DEVICE_NAME L"_CalloutForwardNetworkIPv4",
L"" WINDIVERT_DEVICE_NAME L" callout network (forward IPv4)",
L"" WINDIVERT_DEVICE_NAME L"_FilterForwardNetworkIPv4",
L"" WINDIVERT_DEVICE_NAME L" filter network (forward IPv4)",
{0},
{0},
windivert_classify_forward_network_v4_callout,
};
static layer_t layer_forward_network_ipv4 = &layer_forward_network_ipv4_0;
static struct layer_s layer_forward_network_ipv6_0 =
{
L"" WINDIVERT_DEVICE_NAME L"_SubLayerForwardNetworkIPv6",
L"" WINDIVERT_DEVICE_NAME L" sublayer network (forward IPv6)",
L"" WINDIVERT_DEVICE_NAME L"_CalloutForwardNetworkIPv6",
L"" WINDIVERT_DEVICE_NAME L" callout network (forward IPv6)",
L"" WINDIVERT_DEVICE_NAME L"_FilterForwardNetworkIPv6",
L"" WINDIVERT_DEVICE_NAME L" filter network (forward IPv6)",
{0},
{0},
windivert_classify_forward_network_v6_callout,
};
static layer_t layer_forward_network_ipv6 = &layer_forward_network_ipv6_0;
/*
* WinDivert malloc/free.
*/
static PVOID windivert_malloc(SIZE_T size, BOOL paged)
{
POOL_TYPE pool = (paged? PagedPool: non_paged_pool);
return ExAllocatePoolWithTag(pool, size, WINDIVERT_TAG);
}
static VOID windivert_free(PVOID ptr)
{
if (ptr != NULL)
{
ExFreePoolWithTag(ptr, WINDIVERT_TAG);
}
}
/*
* WinDivert driver entry routine.
*/
extern NTSTATUS DriverEntry(IN PDRIVER_OBJECT driver_obj,
IN PUNICODE_STRING reg_path)
{
WDF_DRIVER_CONFIG config;
WDFDRIVER driver;
PWDFDEVICE_INIT device_init;
WDFDEVICE device;
WDF_FILEOBJECT_CONFIG file_config;
WDF_IO_QUEUE_CONFIG queue_config;
WDFQUEUE queue;
WDF_OBJECT_ATTRIBUTES obj_attrs;
NET_BUFFER_LIST_POOL_PARAMETERS nbl_pool_params;
NET_BUFFER_POOL_PARAMETERS nb_pool_params;
RTL_OSVERSIONINFOW version;
LARGE_INTEGER freq;
NTSTATUS status;
DECLARE_CONST_UNICODE_STRING(device_name,
L"\\Device\\" WINDIVERT_DEVICE_NAME);
DECLARE_CONST_UNICODE_STRING(dos_device_name,
L"\\??\\" WINDIVERT_DEVICE_NAME);
DEBUG("LOAD: loading WinDivert driver");
// Use the "no execute" pool if available:
status = RtlGetVersion(&version);
if (NT_SUCCESS(status))
{
if (version.dwMajorVersion > 6 ||
(version.dwMajorVersion == 6 && version.dwMinorVersion >= 2))
{
non_paged_pool = (POOL_TYPE)512; // NonPagedPoolNx (documented)
}
}
// Initialize timer info.
KeQueryPerformanceCounter(&freq);
counts_per_ms = (ULONGLONG)freq.QuadPart / 1000;
counts_per_ms = (counts_per_ms == 0? 1: counts_per_ms);
// Initialize the layers.
layer_inbound_network_ipv4->layer_guid = FWPM_LAYER_INBOUND_IPPACKET_V4;
layer_outbound_network_ipv4->layer_guid = FWPM_LAYER_OUTBOUND_IPPACKET_V4;
layer_inbound_network_ipv6->layer_guid = FWPM_LAYER_INBOUND_IPPACKET_V6;
layer_outbound_network_ipv6->layer_guid = FWPM_LAYER_OUTBOUND_IPPACKET_V6;
layer_forward_network_ipv4->layer_guid = FWPM_LAYER_IPFORWARD_V4;
layer_forward_network_ipv6->layer_guid = FWPM_LAYER_IPFORWARD_V6;
layer_inbound_network_ipv4->sublayer_guid =
WINDIVERT_SUBLAYER_INBOUND_IPV4_GUID;
layer_outbound_network_ipv4->sublayer_guid =
WINDIVERT_SUBLAYER_OUTBOUND_IPV4_GUID;
layer_inbound_network_ipv6->sublayer_guid =
WINDIVERT_SUBLAYER_INBOUND_IPV6_GUID;
layer_outbound_network_ipv6->sublayer_guid =
WINDIVERT_SUBLAYER_OUTBOUND_IPV6_GUID;
layer_forward_network_ipv4->sublayer_guid =
WINDIVERT_SUBLAYER_FORWARD_IPV4_GUID;
layer_forward_network_ipv6->sublayer_guid =
WINDIVERT_SUBLAYER_FORWARD_IPV6_GUID;
// Configure ourself as a non-PnP driver:
WDF_DRIVER_CONFIG_INIT(&config, WDF_NO_EVENT_CALLBACK);
config.DriverInitFlags |= WdfDriverInitNonPnpDriver;
config.EvtDriverUnload = windivert_unload;
status = WdfDriverCreate(driver_obj, reg_path, WDF_NO_OBJECT_ATTRIBUTES,
&config, &driver);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to create WDF driver", status);
goto driver_entry_exit;
}
device_init = WdfControlDeviceInitAllocate(driver,
&SDDL_DEVOBJ_SYS_ALL_ADM_ALL);
if (device_init == NULL)
{
status = STATUS_INSUFFICIENT_RESOURCES;
DEBUG_ERROR("failed to allocate WDF control device init structure",
status);
goto driver_entry_exit;
}
WdfDeviceInitSetDeviceType(device_init, FILE_DEVICE_NETWORK);
WdfDeviceInitSetIoType(device_init, WdfDeviceIoDirect);
status = WdfDeviceInitAssignName(device_init, &device_name);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to create WDF device name", status);
WdfDeviceInitFree(device_init);
goto driver_entry_exit;
}
WDF_FILEOBJECT_CONFIG_INIT(&file_config, windivert_create, windivert_close,
windivert_cleanup);
WDF_OBJECT_ATTRIBUTES_INIT_CONTEXT_TYPE(&obj_attrs, context_s);
obj_attrs.ExecutionLevel = WdfExecutionLevelPassive;
obj_attrs.SynchronizationScope = WdfSynchronizationScopeNone;
obj_attrs.EvtDestroyCallback = windivert_destroy;
WdfDeviceInitSetFileObjectConfig(device_init, &file_config, &obj_attrs);
WdfDeviceInitSetIoInCallerContextCallback(device_init,
windivert_caller_context);
WDF_OBJECT_ATTRIBUTES_INIT(&obj_attrs);
status = WdfDeviceCreate(&device_init, &obj_attrs, &device);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to create WDF control device", status);
WdfDeviceInitFree(device_init);
goto driver_entry_exit;
}
WDF_IO_QUEUE_CONFIG_INIT_DEFAULT_QUEUE(&queue_config,
WdfIoQueueDispatchParallel);
queue_config.EvtIoRead = NULL;
queue_config.EvtIoWrite = NULL;
queue_config.EvtIoDeviceControl = windivert_ioctl;
WDF_OBJECT_ATTRIBUTES_INIT(&obj_attrs);
obj_attrs.ExecutionLevel = WdfExecutionLevelPassive;
obj_attrs.SynchronizationScope = WdfSynchronizationScopeNone;
status = WdfIoQueueCreate(device, &queue_config, &obj_attrs, &queue);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to create default WDF queue", status);
goto driver_entry_exit;
}
status = WdfDeviceCreateSymbolicLink(device, &dos_device_name);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to create device symbolic link", status);
goto driver_entry_exit;
}
WdfControlFinishInitializing(device);
// Create the packet injection handles.
status = FwpsInjectionHandleCreate0(AF_INET,
FWPS_INJECTION_TYPE_NETWORK | FWPS_INJECTION_TYPE_FORWARD,
&inject_handle);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to create WFP packet injection handle", status);
goto driver_entry_exit;
}
status = FwpsInjectionHandleCreate0(AF_INET6,
FWPS_INJECTION_TYPE_NETWORK | FWPS_INJECTION_TYPE_FORWARD,
&injectv6_handle);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to create WFP ipv6 packet injection handle",
status);
goto driver_entry_exit;
}
// Create a NET_BUFFER_LIST pool handle.
RtlZeroMemory(&nbl_pool_params, sizeof(nbl_pool_params));
nbl_pool_params.Header.Type = NDIS_OBJECT_TYPE_DEFAULT;
nbl_pool_params.Header.Revision =
NET_BUFFER_LIST_POOL_PARAMETERS_REVISION_1;
nbl_pool_params.Header.Size = sizeof(nbl_pool_params);
nbl_pool_params.fAllocateNetBuffer = TRUE;
nbl_pool_params.PoolTag = WINDIVERT_TAG;
nbl_pool_params.DataSize = 0;
nbl_pool_handle = NdisAllocateNetBufferListPool(NULL, &nbl_pool_params);
if (nbl_pool_handle == NULL)
{
status = STATUS_INSUFFICIENT_RESOURCES;
DEBUG_ERROR("failed to allocate net buffer list pool", status);
goto driver_entry_exit;
}
// Create a NET_BUFFER pool handle.
RtlZeroMemory(&nb_pool_params, sizeof(nb_pool_params));
nb_pool_params.Header.Type = NDIS_OBJECT_TYPE_DEFAULT;
nb_pool_params.Header.Revision = NET_BUFFER_POOL_PARAMETERS_REVISION_1;
nb_pool_params.Header.Size =
NDIS_SIZEOF_NET_BUFFER_POOL_PARAMETERS_REVISION_1;
nb_pool_params.PoolTag = WINDIVERT_TAG;
nb_pool_params.DataSize = 0;
nb_pool_handle = NdisAllocateNetBufferPool(NULL, &nb_pool_params);
if (nb_pool_handle == NULL)
{
status = STATUS_INSUFFICIENT_RESOURCES;
DEBUG_ERROR("failed to allocate net buffer pool", status);
goto driver_entry_exit;
}
// Open a handle to the filter engine:
status = FwpmEngineOpen0(NULL, RPC_C_AUTHN_DEFAULT, NULL, NULL,
&engine_handle);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to create WFP engine handle", status);
goto driver_entry_exit;
}
// Register WFP sub-layers:
status = FwpmTransactionBegin0(engine_handle, 0);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to begin WFP transaction", status);
goto driver_entry_exit;
}
status = windivert_install_sublayer(layer_inbound_network_ipv4);
if (!NT_SUCCESS(status))
{
driver_entry_sublayer_error:
DEBUG_ERROR("failed to install WFP sub-layer", status);
FwpmTransactionAbort0(engine_handle);
goto driver_entry_exit;
}
status = windivert_install_sublayer(layer_outbound_network_ipv4);
if (!NT_SUCCESS(status))
{
goto driver_entry_sublayer_error;
}
status = windivert_install_sublayer(layer_inbound_network_ipv6);
if (!NT_SUCCESS(status))
{
goto driver_entry_sublayer_error;
}
status = windivert_install_sublayer(layer_outbound_network_ipv6);
if (!NT_SUCCESS(status))
{
goto driver_entry_sublayer_error;
}
status = windivert_install_sublayer(layer_forward_network_ipv4);
if (!NT_SUCCESS(status))
{
goto driver_entry_sublayer_error;
}
status = windivert_install_sublayer(layer_forward_network_ipv6);
if (!NT_SUCCESS(status))
{
goto driver_entry_sublayer_error;
}
status = FwpmTransactionCommit0(engine_handle);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to commit WFP transaction", status);
goto driver_entry_exit;
}
driver_entry_exit:
if (!NT_SUCCESS(status))
{
windivert_driver_unload();
}
return status;
}
/*
* WinDivert driver unload routine.
*/
extern VOID windivert_unload(IN WDFDRIVER Driver)
{
windivert_driver_unload();
}
/*
* WinDivert driver unload.
*/
static void windivert_driver_unload(void)
{
NTSTATUS status;
DEBUG("UNLOAD: unloading the WinDivert driver");
if (inject_handle != NULL)
{
FwpsInjectionHandleDestroy0(inject_handle);
}
if (injectv6_handle != NULL)
{
FwpsInjectionHandleDestroy0(injectv6_handle);
}
if (nbl_pool_handle != NULL)
{
NdisFreeNetBufferListPool(nbl_pool_handle);
}
if (nb_pool_handle != NULL)
{
NdisFreeNetBufferPool(nb_pool_handle);
}
if (engine_handle != NULL)
{
status = FwpmTransactionBegin0(engine_handle, 0);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to begin WFP transaction", status);
FwpmEngineClose0(engine_handle);
return;
}
FwpmSubLayerDeleteByKey0(engine_handle,
&layer_inbound_network_ipv4->sublayer_guid);
FwpmSubLayerDeleteByKey0(engine_handle,
&layer_outbound_network_ipv4->sublayer_guid);
FwpmSubLayerDeleteByKey0(engine_handle,
&layer_inbound_network_ipv6->sublayer_guid);
FwpmSubLayerDeleteByKey0(engine_handle,
&layer_outbound_network_ipv6->sublayer_guid);
FwpmSubLayerDeleteByKey0(engine_handle,
&layer_forward_network_ipv4->sublayer_guid);
FwpmSubLayerDeleteByKey0(engine_handle,
&layer_forward_network_ipv6->sublayer_guid);
status = FwpmTransactionCommit0(engine_handle);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to commit WFP transaction", status);
}
FwpmEngineClose0(engine_handle);
}
}
/*
* Register a sub-layer.
*/
static NTSTATUS windivert_install_sublayer(layer_t layer)
{
FWPM_SUBLAYER0 sublayer;
NTSTATUS status;
RtlZeroMemory(&sublayer, sizeof(sublayer));
sublayer.subLayerKey = layer->sublayer_guid;
sublayer.displayData.name = layer->sublayer_name;
sublayer.displayData.description = layer->sublayer_desc;
sublayer.weight = UINT16_MAX;
status = FwpmSubLayerAdd0(engine_handle, &sublayer, NULL);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to add WFP sub-layer", status);
}
return status;
}
/*
* WinDivert create routine.
*/
extern VOID windivert_create(IN WDFDEVICE device, IN WDFREQUEST request,
IN WDFFILEOBJECT object)
{
WDF_IO_QUEUE_CONFIG queue_config;
WDF_WORKITEM_CONFIG item_config;
WDF_OBJECT_ATTRIBUTES obj_attrs;
FWPM_SESSION0 session;
NTSTATUS status = STATUS_SUCCESS;
UINT8 i;
context_t context = windivert_context_get(object);
DEBUG("CREATE: creating a new WinDivert context (context=%p)", context);
// Initialise the new context:
context->state = WINDIVERT_CONTEXT_STATE_OPENING;
context->device = device;
context->object = object;
context->work_queue_length = 0;
context->packet_queue_length = 0;
context->packet_queue_maxlength = WINDIVERT_PARAM_QUEUE_LEN_DEFAULT;
context->packet_queue_size = 0;
context->packet_queue_maxsize = WINDIVERT_PARAM_QUEUE_SIZE_DEFAULT;
context->packet_queue_maxcounts =
WINDIVERT_PARAM_QUEUE_TIME_DEFAULT * counts_per_ms;
context->packet_queue_maxtime = WINDIVERT_PARAM_QUEUE_TIME_DEFAULT;
context->layer = WINDIVERT_LAYER_DEFAULT;
context->flags = 0;
context->priority = WINDIVERT_CONTEXT_PRIORITY(WINDIVERT_PRIORITY_DEFAULT);
context->filter = NULL;
for (i = 0; i < WINDIVERT_CONTEXT_MAXWORKERS; i++)
{
context->workers[i] = NULL;
}
context->worker_curr = 0;
for (i = 0; i < WINDIVERT_CONTEXT_MAXLAYERS; i++)
{
context->installed[i] = FALSE;
}
context->on = FALSE;
KeInitializeSpinLock(&context->lock);
InitializeListHead(&context->work_queue);
InitializeListHead(&context->packet_queue);
for (i = 0; i < WINDIVERT_CONTEXT_MAXLAYERS; i++)
{
status = ExUuidCreate(&context->callout_guid[i]);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to create callout GUID", status);
goto windivert_create_exit;
}
status = ExUuidCreate(&context->filter_guid[i]);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to create filter GUID", status);
goto windivert_create_exit;
}
}
WDF_IO_QUEUE_CONFIG_INIT(&queue_config, WdfIoQueueDispatchManual);
status = WdfIoQueueCreate(device, &queue_config, WDF_NO_OBJECT_ATTRIBUTES,
&context->read_queue);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to create I/O read queue", status);
goto windivert_create_exit;
}
WDF_WORKITEM_CONFIG_INIT(&item_config, windivert_worker);
item_config.AutomaticSerialization = FALSE;
WDF_OBJECT_ATTRIBUTES_INIT(&obj_attrs);
obj_attrs.ParentObject = (WDFOBJECT)object;
for (i = 0; i < WINDIVERT_CONTEXT_MAXWORKERS; i++)
{
status = WdfWorkItemCreate(&item_config, &obj_attrs,
context->workers + i);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to create read service work item", status);
goto windivert_create_exit;
}
}
RtlZeroMemory(&session, sizeof(session));
session.flags |= FWPM_SESSION_FLAG_DYNAMIC;
status = FwpmEngineOpen0(NULL, RPC_C_AUTHN_DEFAULT, NULL, &session,
&context->engine_handle);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to create WFP engine handle", status);
goto windivert_create_exit;
}
context->state = WINDIVERT_CONTEXT_STATE_OPEN;
windivert_create_exit:
// Clean-up on error:
if (!NT_SUCCESS(status))
{
context->state = WINDIVERT_CONTEXT_STATE_INVALID;
if (context->read_queue != NULL)
{
WdfObjectDelete(context->read_queue);
}
for (i = 0; i < WINDIVERT_CONTEXT_MAXWORKERS; i++)
{
if (context->workers[i] != NULL)
{
WdfObjectDelete(context->workers[i]);
}
}
if (context->engine_handle != NULL)
{
FwpmEngineClose0(context->engine_handle);
}
}
WdfRequestComplete(request, status);
}
/*
* Register all WFP callouts.
*/
static NTSTATUS windivert_install_callouts(context_t context, UINT8 layer,
BOOL is_inbound, BOOL is_outbound, BOOL is_ipv4, BOOL is_ipv6)
{
UINT8 i, j;
layer_t layers[WINDIVERT_CONTEXT_MAXLAYERS];
NTSTATUS status;
i = 0;
switch (layer)
{
case WINDIVERT_LAYER_NETWORK:
if (is_inbound && is_ipv4)
{
layers[i++] = layer_inbound_network_ipv4;
}
if (is_outbound && is_ipv4)
{
layers[i++] = layer_outbound_network_ipv4;
}
if (is_inbound && is_ipv6)
{
layers[i++] = layer_inbound_network_ipv6;
}
if (is_outbound && is_ipv6)
{
layers[i++] = layer_outbound_network_ipv6;
}
break;
case WINDIVERT_LAYER_NETWORK_FORWARD:
if (is_ipv4)
{
layers[i++] = layer_forward_network_ipv4;
}
if (is_ipv6)
{
layers[i++] = layer_forward_network_ipv6;
}
break;
default:
return STATUS_INVALID_PARAMETER;
}
for (j = 0; j < i; j++)
{
status = windivert_install_callout(context, j, layers[j]);
if (!NT_SUCCESS(status))
{
goto windivert_install_callouts_exit;
}
}
windivert_install_callouts_exit:
if (!NT_SUCCESS(status))
{
windivert_uninstall_callouts(context, WINDIVERT_CONTEXT_STATE_OPEN);
}
return status;
}
/*
* Register a WFP callout.
*/
static NTSTATUS windivert_install_callout(context_t context, UINT idx,
layer_t layer)
{
KLOCK_QUEUE_HANDLE lock_handle;
FWPS_CALLOUT0 scallout;
FWPM_CALLOUT0 mcallout;
FWPM_FILTER0 filter;
UINT64 weight;
UINT32 priority;
GUID callout_guid, filter_guid;
WDFDEVICE device;
HANDLE engine_handle;
NTSTATUS status;
KeAcquireInStackQueuedSpinLock(&context->lock, &lock_handle);
if (context->state != WINDIVERT_CONTEXT_STATE_OPEN)
{
KeReleaseInStackQueuedSpinLock(&lock_handle);
status = STATUS_INVALID_DEVICE_STATE;
return status;
}
priority = context->priority;
callout_guid = context->callout_guid[idx];
filter_guid = context->filter_guid[idx];
device = context->device;
engine_handle = context->engine_handle;
KeReleaseInStackQueuedSpinLock(&lock_handle);
weight = WINDIVERT_FILTER_WEIGHT(priority);
RtlZeroMemory(&scallout, sizeof(scallout));
scallout.calloutKey = callout_guid;
scallout.classifyFn = layer->callout;
scallout.notifyFn = windivert_notify_callout;
scallout.flowDeleteFn = NULL;
RtlZeroMemory(&mcallout, sizeof(mcallout));
mcallout.calloutKey = callout_guid;
mcallout.displayData.name = layer->callout_name;
mcallout.displayData.description = layer->callout_desc;
mcallout.applicableLayer = layer->layer_guid;
RtlZeroMemory(&filter, sizeof(filter));
filter.filterKey = filter_guid;
filter.layerKey = layer->layer_guid;
filter.displayData.name = layer->filter_name;
filter.displayData.description = layer->filter_desc;
filter.action.type = FWP_ACTION_CALLOUT_UNKNOWN;
filter.action.calloutKey = callout_guid;
filter.subLayerKey = layer->sublayer_guid;
filter.weight.type = FWP_UINT64;
filter.weight.uint64 = &weight;
filter.rawContext = (UINT64)context;
status = FwpsCalloutRegister0(WdfDeviceWdmGetDeviceObject(device),
&scallout, NULL);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to install WFP callout", status);
return status;
}
status = FwpmTransactionBegin0(engine_handle, 0);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to begin WFP transaction", status);
FwpsCalloutUnregisterByKey0(&callout_guid);
return status;
}
status = FwpmCalloutAdd0(engine_handle, &mcallout, NULL, NULL);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to add WFP callout", status);
goto windivert_install_callout_error;
}
status = FwpmFilterAdd0(engine_handle, &filter, NULL, NULL);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to add WFP filter", status);
goto windivert_install_callout_error;
}
status = FwpmTransactionCommit0(engine_handle);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to commit WFP transaction", status);
FwpsCalloutUnregisterByKey0(&callout_guid);
return status;
}
KeAcquireInStackQueuedSpinLock(&context->lock, &lock_handle);
if (context->state != WINDIVERT_CONTEXT_STATE_OPEN)
{
KeReleaseInStackQueuedSpinLock(&lock_handle);
FwpsCalloutUnregisterByKey0(&callout_guid);
status = STATUS_INVALID_DEVICE_STATE;
return status;
}
context->installed[idx] = TRUE;
KeReleaseInStackQueuedSpinLock(&lock_handle);
return STATUS_SUCCESS;
windivert_install_callout_error:
FwpmTransactionAbort0(engine_handle);
FwpsCalloutUnregisterByKey0(&callout_guid);
return status;
}
/*
* WinDivert uninstall callouts routine.
*/
static void windivert_uninstall_callouts(context_t context,
context_state_t state)
{
KLOCK_QUEUE_HANDLE lock_handle;
UINT i;
HANDLE engine_handle;
BOOL installed;
GUID callout_guid, filter_guid;
NTSTATUS status;
KeAcquireInStackQueuedSpinLock(&context->lock, &lock_handle);
if (context->state != state)
{
windivert_uninstall_callouts_error:
KeReleaseInStackQueuedSpinLock(&lock_handle);
status = STATUS_INVALID_DEVICE_STATE;
DEBUG_ERROR("failed to delete filters and callouts", status);
return;
}
engine_handle = context->engine_handle;
KeReleaseInStackQueuedSpinLock(&lock_handle);
status = FwpmTransactionBegin0(engine_handle, 0);
if (!NT_SUCCESS(status))
{
// If the userspace app closes without closing the handle to
// WinDivert, any actions on engine_handle fail because the
// RPC handle was closed first. So, this path is "normal" if
// the user's app crashed or never closed the WinDivert handle.
DEBUG_ERROR("failed to begin WFP transaction", status);
goto unregister_callouts;
}
for (i = 0; i < WINDIVERT_CONTEXT_MAXLAYERS; i++)
{
KeAcquireInStackQueuedSpinLock(&context->lock, &lock_handle);
if (context->state != state)
{
KeReleaseInStackQueuedSpinLock(&lock_handle);
FwpmTransactionAbort0(engine_handle);
status = STATUS_INVALID_DEVICE_STATE;
DEBUG_ERROR("failed to delete filters and callouts", status);
return;
}
installed = context->installed[i];
callout_guid = context->callout_guid[i];
filter_guid = context->filter_guid[i];
KeReleaseInStackQueuedSpinLock(&lock_handle);
if (!installed)
{
continue;
}
status = FwpmFilterDeleteByKey0(engine_handle, &filter_guid);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to delete filter", status);
break;
}
status = FwpmCalloutDeleteByKey0(engine_handle, &callout_guid);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to delete callout", status);
break;
}
}
if (!NT_SUCCESS(status))
{
FwpmTransactionAbort0(engine_handle);
goto unregister_callouts;
}
status = FwpmTransactionCommit0(engine_handle);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to commit WFP transaction", status);
//fallthrough
}
unregister_callouts:
for (i = 0; i < WINDIVERT_CONTEXT_MAXLAYERS; i++)
{
KeAcquireInStackQueuedSpinLock(&context->lock, &lock_handle);
if (context->state != state)
{
goto windivert_uninstall_callouts_error;
}
installed = context->installed[i];
callout_guid = context->callout_guid[i];
context->installed[i] = FALSE;
KeReleaseInStackQueuedSpinLock(&lock_handle);
if (!installed)
{
continue;
}
FwpsCalloutUnregisterByKey0(&callout_guid);
}
}
/*
* Divert cleanup routine.
*/
extern VOID windivert_cleanup(IN WDFFILEOBJECT object)
{
KLOCK_QUEUE_HANDLE lock_handle;
PLIST_ENTRY entry;
UINT i;
context_t context = windivert_context_get(object);
work_t work;
packet_t packet;
WDFQUEUE read_queue;
WDFWORKITEM worker;
NTSTATUS status;
DEBUG("CLEANUP: cleaning up WinDivert context (context=%p)", context);
KeAcquireInStackQueuedSpinLock(&context->lock, &lock_handle);
if (context->state != WINDIVERT_CONTEXT_STATE_OPEN)
{
windivert_cleanup_error:
KeReleaseInStackQueuedSpinLock(&lock_handle);
status = STATUS_INVALID_DEVICE_STATE;
DEBUG_ERROR("failed to verify state for cleanup routine", status);
return;
}
context->state = WINDIVERT_CONTEXT_STATE_CLOSING;
while (!IsListEmpty(&context->work_queue))
{
entry = RemoveHeadList(&context->work_queue);
context->work_queue_length--;
KeReleaseInStackQueuedSpinLock(&lock_handle);
work = CONTAINING_RECORD(entry, struct work_s, entry);
FwpsDereferenceNetBufferList(work->buffers, FALSE);
windivert_free(work);
KeAcquireInStackQueuedSpinLock(&context->lock, &lock_handle);
if (context->state != WINDIVERT_CONTEXT_STATE_CLOSING)
{
goto windivert_cleanup_error;
}
}
while (!IsListEmpty(&context->packet_queue))
{
entry = RemoveHeadList(&context->packet_queue);
packet = CONTAINING_RECORD(entry, struct packet_s, entry);
context->packet_queue_length--;
context->packet_queue_size -= packet->data_len;
KeReleaseInStackQueuedSpinLock(&lock_handle);
windivert_free_packet(packet);
KeAcquireInStackQueuedSpinLock(&context->lock, &lock_handle);
if (context->state != WINDIVERT_CONTEXT_STATE_CLOSING)
{
goto windivert_cleanup_error;
}
}
read_queue = context->read_queue;
KeReleaseInStackQueuedSpinLock(&lock_handle);
WdfIoQueuePurge(read_queue, NULL, NULL);
WdfObjectDelete(read_queue);
for (i = 0; i < WINDIVERT_CONTEXT_MAXWORKERS; i++)
{
KeAcquireInStackQueuedSpinLock(&context->lock, &lock_handle);
if (context->state != WINDIVERT_CONTEXT_STATE_CLOSING)
{
goto windivert_cleanup_error;
}
worker = context->workers[i];
KeReleaseInStackQueuedSpinLock(&lock_handle);
WdfWorkItemFlush(worker);
WdfObjectDelete(worker);
}
windivert_uninstall_callouts(context, WINDIVERT_CONTEXT_STATE_CLOSING);
FwpmEngineClose0(context->engine_handle);
}
/*
* WinDivert close routine.
*/
extern VOID windivert_close(IN WDFFILEOBJECT object)
{
KLOCK_QUEUE_HANDLE lock_handle;
context_t context = windivert_context_get(object);
NTSTATUS status;
DEBUG("CLOSE: closing WinDivert context (context=%p)", context);
KeAcquireInStackQueuedSpinLock(&context->lock, &lock_handle);
if (context->state != WINDIVERT_CONTEXT_STATE_CLOSING)
{
KeReleaseInStackQueuedSpinLock(&lock_handle);
status = STATUS_INVALID_DEVICE_STATE;
DEBUG_ERROR("failed to verify state for close routine", status);
return;
}
context->state = WINDIVERT_CONTEXT_STATE_CLOSED;
KeReleaseInStackQueuedSpinLock(&lock_handle);
}
/*
* WinDivert destroy routine.
*/
extern VOID windivert_destroy(IN WDFOBJECT object)
{
KLOCK_QUEUE_HANDLE lock_handle;
context_t context = windivert_context_get((WDFFILEOBJECT)object);
filter_t filter;
NTSTATUS status;
DEBUG("DESTROY: destroying WinDivert context (context=%p)", context);
KeAcquireInStackQueuedSpinLock(&context->lock, &lock_handle);
if (context->state != WINDIVERT_CONTEXT_STATE_CLOSED)
{
KeReleaseInStackQueuedSpinLock(&lock_handle);
status = STATUS_INVALID_DEVICE_STATE;
DEBUG_ERROR("failed to verify state for destroy routine", status);
return;
}
filter = context->filter;
KeReleaseInStackQueuedSpinLock(&lock_handle);
windivert_free(filter);
}
/*
* WinDivert read routine.
*/
static NTSTATUS windivert_read(context_t context, WDFREQUEST request)
{
NTSTATUS status = STATUS_SUCCESS;
DEBUG("READ: reading diverted packet (context=%p, request=%p)", context,
request);
// Forward the request to the pending read queue:
status = WdfRequestForwardToIoQueue(request, context->read_queue);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to forward I/O request to read queue", status);
return status;
}
// Service the read request:
windivert_read_service(context);
return STATUS_SUCCESS;
}
/*
* WinDivert service a single read request.
*/
static void windivert_read_service_request(packet_t packet,
PNET_BUFFER buffer, UINT8 direction, UINT32 if_idx, UINT32 sub_if_idx,
BOOL hop, UINT8 checksums, WDFREQUEST request)
{
PMDL dst_mdl;
PVOID dst, src;
ULONG dst_len, src_len;
NTSTATUS status;
req_context_t req_context;
windivert_addr_t addr;
DEBUG("SERVICE: servicing read request (request=%p)", request);
status = WdfRequestRetrieveOutputWdmMdl(request, &dst_mdl);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to retrieve output MDL", status);
goto windivert_read_service_request_exit;
}
dst = MmGetSystemAddressForMdlSafe(dst_mdl, NormalPagePriority);
if (dst == NULL)
{
status = STATUS_INSUFFICIENT_RESOURCES;
DEBUG_ERROR("failed to get address of output MDL", status);
goto windivert_read_service_request_exit;
}
dst_len = MmGetMdlByteCount(dst_mdl);
if (packet != NULL)
{
src_len = packet->data_len;
dst_len = (src_len < dst_len? src_len: dst_len);
src = packet->data;
RtlCopyMemory(dst, src, dst_len);
}
else
{
src_len = NET_BUFFER_DATA_LENGTH(buffer);
dst_len = (src_len < dst_len? src_len: dst_len);
src = NdisGetDataBuffer(buffer, dst_len, NULL, 1, 0);
if (src == NULL)
{
NdisGetDataBuffer(buffer, dst_len, dst, 1, 0);
}
else
{
RtlCopyMemory(dst, src, dst_len);
}
}
// Write the address information.
req_context = windivert_req_context_get(request);
addr = req_context->addr;
if (addr != NULL)
{
addr->IfIdx = if_idx;
addr->SubIfIdx = sub_if_idx;
addr->Direction = direction;
}
// Zero the IP/TCP/UDP checksums and/or decrement the TTL (if required).
status = windivert_finalize_packet(dst, dst_len, hop, checksums);
windivert_read_service_request_exit:
if (NT_SUCCESS(status))
{
WdfRequestCompleteWithInformation(request, status, dst_len);
}
else
{
WdfRequestComplete(request, status);
}
}
/*
* WinDivert read request service.
*/
static void windivert_read_service(context_t context)
{
KLOCK_QUEUE_HANDLE lock_handle;
WDFREQUEST request;
PLIST_ENTRY entry;
PMDL dst_mdl;
PVOID dst, src;
ULONG dst_len, src_len;
ULONGLONG timestamp;
BOOL timeout;
NTSTATUS status;
packet_t packet;
req_context_t req_context;
windivert_addr_t addr;
timestamp = (ULONGLONG)KeQueryPerformanceCounter(NULL).QuadPart;
KeAcquireInStackQueuedSpinLock(&context->lock, &lock_handle);
while (context->state == WINDIVERT_CONTEXT_STATE_OPEN &&
!IsListEmpty(&context->packet_queue))
{
entry = RemoveHeadList(&context->packet_queue);
packet = CONTAINING_RECORD(entry, struct packet_s, entry);
timeout = (timestamp - packet->timestamp >
context->packet_queue_maxcounts);
request = NULL;
if (!timeout)
{
status = WdfIoQueueRetrieveNextRequest(context->read_queue,
&request);
if (!NT_SUCCESS(status))
{
InsertHeadList(&context->packet_queue, entry);
break;
}
}
context->packet_queue_length--;
context->packet_queue_size -= packet->data_len;
KeReleaseInStackQueuedSpinLock(&lock_handle);
if (!timeout)
{
windivert_read_service_request(packet, NULL,
packet->direction, packet->if_idx, packet->sub_if_idx,
packet->hop, packet->checksums, request);
}
windivert_free_packet(packet);
timestamp = (ULONGLONG)KeQueryPerformanceCounter(NULL).QuadPart;
KeAcquireInStackQueuedSpinLock(&context->lock, &lock_handle);
}
KeReleaseInStackQueuedSpinLock(&lock_handle);
}
/*
* WinDivert write routine.
*/
static NTSTATUS windivert_write(context_t context, WDFREQUEST request,
windivert_addr_t addr)
{
KLOCK_QUEUE_HANDLE lock_handle;
PMDL mdl = NULL, mdl_copy = NULL;
PVOID data, data_copy = NULL;
UINT data_len;
struct iphdr *ip_header;
struct ipv6hdr *ipv6_header;
BOOL isipv4;
UINT8 layer;
UINT32 priority;
HANDLE handle;
PNET_BUFFER_LIST buffers = NULL;
NTSTATUS status = STATUS_SUCCESS;
DEBUG("WRITE: writing/injecting a packet (context=%p, request=%p)",
context, request);
if (addr->Direction != WINDIVERT_DIRECTION_INBOUND &&
addr->Direction != WINDIVERT_DIRECTION_OUTBOUND)
{
status = STATUS_INVALID_PARAMETER;
DEBUG_ERROR("failed to inject packet; invalid direction", status);
goto windivert_write_exit;
}
status = WdfRequestRetrieveOutputWdmMdl(request, &mdl);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to retrieve input MDL", status);
goto windivert_write_exit;
}
data = MmGetSystemAddressForMdlSafe(mdl, NormalPagePriority);
if (data == NULL)
{
status = STATUS_INSUFFICIENT_RESOURCES;
DEBUG_ERROR("failed to get MDL address", status);
goto windivert_write_exit;
}
data_len = MmGetMdlByteCount(mdl);
if (data_len > UINT16_MAX || data_len < sizeof(struct iphdr))
{
windivert_write_bad_packet:
status = STATUS_INVALID_PARAMETER;
DEBUG_ERROR("failed to inject a bad packet", status);
goto windivert_write_exit;
}
data_copy = windivert_malloc(data_len, FALSE);
if (data_copy == NULL)
{
status = STATUS_INSUFFICIENT_RESOURCES;
DEBUG_ERROR("failed to allocate memory for injected packet data",
status);
goto windivert_write_exit;
}
RtlCopyMemory(data_copy, data, sizeof(struct iphdr));
ip_header = (struct iphdr *)data_copy;
switch (ip_header->Version)
{
case 4:
if (data_len != RtlUshortByteSwap(ip_header->Length))
goto windivert_write_bad_packet;
isipv4 = TRUE;
break;
case 6:
if (data_len < sizeof(struct ipv6hdr))
goto windivert_write_bad_packet;
ipv6_header = (struct ipv6hdr *)data_copy;
if (data_len != RtlUshortByteSwap(ipv6_header->Length) +
sizeof(struct ipv6hdr))
goto windivert_write_bad_packet;
isipv4 = FALSE;
break;
default:
goto windivert_write_bad_packet;
}
if (data_len > sizeof(struct iphdr))
{
RtlCopyMemory((char *)data_copy + sizeof(struct iphdr),
(char *)data + sizeof(struct iphdr),
data_len - sizeof(struct iphdr));
}
mdl_copy = IoAllocateMdl(data_copy, data_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_exit;
}
MmBuildMdlForNonPagedPool(mdl_copy);
status = FwpsAllocateNetBufferAndNetBufferList0(nbl_pool_handle, 0, 0,
mdl_copy, 0, data_len, &buffers);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to create NET_BUFFER_LIST for injected packet",
status);
goto windivert_write_exit;
}
KeAcquireInStackQueuedSpinLock(&context->lock, &lock_handle);
if (context->state != WINDIVERT_CONTEXT_STATE_OPEN)
{
KeReleaseInStackQueuedSpinLock(&lock_handle);
status = STATUS_INVALID_DEVICE_STATE;
goto windivert_write_exit;
}
layer = context->layer;
priority = context->priority;
KeReleaseInStackQueuedSpinLock(&lock_handle);
handle = (isipv4? inject_handle: injectv6_handle);
if (layer == WINDIVERT_LAYER_NETWORK_FORWARD)
{
status = FwpsInjectForwardAsync0(handle, (HANDLE)priority, 0,
(isipv4? AF_INET: AF_INET6), UNSPECIFIED_COMPARTMENT_ID,
addr->IfIdx, buffers, windivert_inject_complete, NULL);
}
else if (addr->Direction == WINDIVERT_DIRECTION_OUTBOUND)
{
status = FwpsInjectNetworkSendAsync0(handle, (HANDLE)priority, 0,
UNSPECIFIED_COMPARTMENT_ID, buffers, windivert_inject_complete,
NULL);
}
else
{
status = FwpsInjectNetworkReceiveAsync0(handle, (HANDLE)priority, 0,
UNSPECIFIED_COMPARTMENT_ID, addr->IfIdx, addr->SubIfIdx, buffers,
windivert_inject_complete, NULL);
}
windivert_write_exit:
if (NT_SUCCESS(status))
{
WdfRequestCompleteWithInformation(request, status, data_len);
}
else
{
DEBUG_ERROR("failed to inject packet", status);
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 *context,
NET_BUFFER_LIST *buffers, BOOLEAN dispatch_level)
{
PMDL mdl;
PVOID data;
PNET_BUFFER buffer;
UNREFERENCED_PARAMETER(context);
UNREFERENCED_PARAMETER(dispatch_level);
buffer = NET_BUFFER_LIST_FIRST_NB(buffers);
mdl = NET_BUFFER_FIRST_MDL(buffer);
data = MmGetSystemAddressForMdlSafe(mdl, NormalPagePriority);
windivert_free(data);
IoFreeMdl(mdl);
FwpsFreeNetBufferList0(buffers);
}
/*
* WinDivert caller context preprocessing.
*/
VOID windivert_caller_context(IN WDFDEVICE device, IN WDFREQUEST request)
{
PCHAR inbuf;
size_t inbuflen;
WDF_REQUEST_PARAMETERS params;
WDFMEMORY memobj;
windivert_addr_t addr = NULL;
windivert_ioctl_t ioctl;
WDF_OBJECT_ATTRIBUTES attributes;
req_context_t req_context = NULL;
NTSTATUS status;
WDF_REQUEST_PARAMETERS_INIT(¶ms);
WdfRequestGetParameters(request, ¶ms);
if (params.Type != WdfRequestTypeDeviceControl)
{
goto windivert_caller_context_exit;
}
// Get and verify the input buffer.
status = WdfRequestRetrieveInputBuffer(request, 0, &inbuf, &inbuflen);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to retrieve input buffer", status);
goto windivert_caller_context_error;
}
if (inbuflen != sizeof(struct windivert_ioctl_s))
{
status = STATUS_INVALID_PARAMETER;
DEBUG_ERROR("input buffer not an ioctl message header", status);
goto windivert_caller_context_error;
}
ioctl = (windivert_ioctl_t)inbuf;
if (ioctl->version != WINDIVERT_IOCTL_VERSION ||
ioctl->magic != WINDIVERT_IOCTL_MAGIC)
{
status = STATUS_INVALID_PARAMETER;
DEBUG_ERROR("input buffer contained a bad ioctl message header",
status);
goto windivert_caller_context_error;
}
// Probe and lock user buffers here (if required).
WDF_OBJECT_ATTRIBUTES_INIT_CONTEXT_TYPE(&attributes, req_context_s);
status = WdfObjectAllocateContext(request, &attributes, &req_context);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to allocate request context for ioctl", status);
goto windivert_caller_context_error;
}
switch (params.Parameters.DeviceIoControl.IoControlCode)
{
case IOCTL_WINDIVERT_RECV:
if ((PVOID)ioctl->arg == NULL)
{
status = STATUS_INVALID_PARAMETER;
DEBUG_ERROR("null arg pointer for RECV ioctl", status);
goto windivert_caller_context_error;
}
status = WdfRequestProbeAndLockUserBufferForWrite(request,
(PVOID)ioctl->arg, sizeof(struct windivert_addr_s), &memobj);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("invalid arg pointer for RECV ioctl", status);
goto windivert_caller_context_error;
}
addr = (windivert_addr_t)WdfMemoryGetBuffer(memobj, NULL);
break;
case IOCTL_WINDIVERT_SEND:
if ((PVOID)ioctl->arg == NULL)
{
status = STATUS_INVALID_PARAMETER;
DEBUG_ERROR("null arg pointer for SEND ioctl", status);
goto windivert_caller_context_error;
}
status = WdfRequestProbeAndLockUserBufferForRead(request,
(PVOID)ioctl->arg, sizeof(struct windivert_addr_s), &memobj);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("invalid arg pointer for SEND ioctl", status);
goto windivert_caller_context_error;
}
addr = (windivert_addr_t)WdfMemoryGetBuffer(memobj, NULL);
break;
case IOCTL_WINDIVERT_START_FILTER:
case IOCTL_WINDIVERT_SET_LAYER:
case IOCTL_WINDIVERT_SET_PRIORITY:
case IOCTL_WINDIVERT_SET_FLAGS:
case IOCTL_WINDIVERT_SET_PARAM:
case IOCTL_WINDIVERT_GET_PARAM:
break;
default:
status = STATUS_INVALID_DEVICE_REQUEST;
DEBUG_ERROR("failed to complete I/O control; invalid request",
status);
goto windivert_caller_context_error;
}
req_context->addr = addr;
windivert_caller_context_exit:
status = WdfDeviceEnqueueRequest(device, request);
windivert_caller_context_error:
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to enqueue request", status);
WdfRequestComplete(request, status);
}
}
/*
* WinDivert I/O control.
*/
extern VOID windivert_ioctl(IN WDFQUEUE queue, IN WDFREQUEST request,
IN size_t out_length, IN size_t in_length, IN ULONG code)
{
KLOCK_QUEUE_HANDLE lock_handle;
PCHAR inbuf, outbuf;
size_t inbuflen, outbuflen, filter0_len;
windivert_ioctl_t ioctl;
windivert_ioctl_filter_t filter0;
filter_t filter;
UINT8 layer;
UINT32 priority;
UINT64 flags;
windivert_addr_t addr;
req_context_t req_context;
NTSTATUS status = STATUS_SUCCESS;
context_t context =
windivert_context_get(WdfRequestGetFileObject(request));
UINT64 value, *valptr;
UNREFERENCED_PARAMETER(queue);
DEBUG("IOCTL: I/O control request (context=%p)", context);
// Get the buffers and do sanity checks.
status = WdfRequestRetrieveInputBuffer(request, 0, &inbuf, &inbuflen);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to retrieve input buffer", status);
goto windivert_ioctl_exit;
}
switch (code)
{
case IOCTL_WINDIVERT_START_FILTER: case IOCTL_WINDIVERT_GET_PARAM:
status = WdfRequestRetrieveOutputBuffer(request, 0, &outbuf,
&outbuflen);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to retrieve output buffer", status);
goto windivert_ioctl_exit;
}
break;
default:
outbuf = NULL;
outbuflen = 0;
break;
}
// Handle the ioctl:
switch (code)
{
case IOCTL_WINDIVERT_RECV:
status = windivert_read(context, request);
if (NT_SUCCESS(status))
{
return;
}
break;
case IOCTL_WINDIVERT_SEND:
req_context = windivert_req_context_get(request);
addr = req_context->addr;
status = windivert_write(context, request, addr);
if (NT_SUCCESS(status))
{
return;
}
break;
case IOCTL_WINDIVERT_START_FILTER:
{
BOOL is_inbound, is_outbound, is_ipv4, is_ipv6;
filter0 = (windivert_ioctl_filter_t)outbuf;
filter0_len = outbuflen;
filter = windivert_filter_compile(filter0, filter0_len);
if (filter == NULL)
{
status = STATUS_INVALID_PARAMETER;
DEBUG_ERROR("failed to compile filter", status);
goto windivert_ioctl_exit;
}
KeAcquireInStackQueuedSpinLock(&context->lock, &lock_handle);
if (context->state != WINDIVERT_CONTEXT_STATE_OPEN || context->on)
{
KeReleaseInStackQueuedSpinLock(&lock_handle);
windivert_free(filter);
status = STATUS_INVALID_DEVICE_STATE;
goto windivert_ioctl_exit;
}
context->on = TRUE;
context->filter = filter;
layer = context->layer;
KeReleaseInStackQueuedSpinLock(&lock_handle);
windivert_filter_analyze(filter, &is_inbound, &is_outbound,
&is_ipv4, &is_ipv6);
status = windivert_install_callouts(context, layer, is_inbound,
is_outbound, is_ipv4, is_ipv6);
break;
}
case IOCTL_WINDIVERT_SET_LAYER:
ioctl = (windivert_ioctl_t)inbuf;
if (ioctl->arg > WINDIVERT_LAYER_MAX)
{
status = STATUS_INVALID_PARAMETER;
DEBUG_ERROR("failed to set layer; value too big", status);
goto windivert_ioctl_exit;
}
layer = (UINT8)ioctl->arg;
KeAcquireInStackQueuedSpinLock(&context->lock, &lock_handle);
if (context->state != WINDIVERT_CONTEXT_STATE_OPEN || context->on)
{
KeReleaseInStackQueuedSpinLock(&lock_handle);
status = STATUS_INVALID_DEVICE_STATE;
goto windivert_ioctl_exit;
}
context->layer = layer;
KeReleaseInStackQueuedSpinLock(&lock_handle);
break;
case IOCTL_WINDIVERT_SET_PRIORITY:
ioctl = (windivert_ioctl_t)inbuf;
if (ioctl->arg < WINDIVERT_PRIORITY_MIN ||
ioctl->arg > WINDIVERT_PRIORITY_MAX)
{
status = STATUS_INVALID_PARAMETER;
DEBUG_ERROR("failed to set priority; value out of range",
status);
goto windivert_ioctl_exit;
}
priority = WINDIVERT_CONTEXT_PRIORITY((UINT32)ioctl->arg);
KeAcquireInStackQueuedSpinLock(&context->lock, &lock_handle);
if (context->state != WINDIVERT_CONTEXT_STATE_OPEN || context->on)
{
KeReleaseInStackQueuedSpinLock(&lock_handle);
status = STATUS_INVALID_DEVICE_STATE;
goto windivert_ioctl_exit;
}
context->priority = priority;
KeReleaseInStackQueuedSpinLock(&lock_handle);
break;
case IOCTL_WINDIVERT_SET_FLAGS:
ioctl = (windivert_ioctl_t)inbuf;
if (!WINDIVERT_FLAGS_VALID(ioctl->arg))
{
status = STATUS_INVALID_PARAMETER;
DEBUG_ERROR("failed to set flags; invalid flags value",
status);
goto windivert_ioctl_exit;
}
flags = ioctl->arg;
KeAcquireInStackQueuedSpinLock(&context->lock, &lock_handle);
if (context->state != WINDIVERT_CONTEXT_STATE_OPEN || context->on)
{
KeReleaseInStackQueuedSpinLock(&lock_handle);
status = STATUS_INVALID_DEVICE_STATE;
goto windivert_ioctl_exit;
}
context->flags = flags;
KeReleaseInStackQueuedSpinLock(&lock_handle);
break;
case IOCTL_WINDIVERT_SET_PARAM:
ioctl = (windivert_ioctl_t)inbuf;
value = ioctl->arg;
KeAcquireInStackQueuedSpinLock(&context->lock, &lock_handle);
if (context->state != WINDIVERT_CONTEXT_STATE_OPEN)
{
KeReleaseInStackQueuedSpinLock(&lock_handle);
status = STATUS_INVALID_DEVICE_STATE;
goto windivert_ioctl_exit;
}
switch ((WINDIVERT_PARAM)ioctl->arg8)
{
case WINDIVERT_PARAM_QUEUE_LEN:
if (value < WINDIVERT_PARAM_QUEUE_LEN_MIN ||
value > WINDIVERT_PARAM_QUEUE_LEN_MAX)
{
KeReleaseInStackQueuedSpinLock(&lock_handle);
status = STATUS_INVALID_PARAMETER;
DEBUG_ERROR("failed to set queue length; invalid "
"value", status);
goto windivert_ioctl_exit;
}
context->packet_queue_maxlength = (ULONG)value;
break;
case WINDIVERT_PARAM_QUEUE_TIME:
if (value < WINDIVERT_PARAM_QUEUE_TIME_MIN ||
value > WINDIVERT_PARAM_QUEUE_TIME_MAX)
{
KeReleaseInStackQueuedSpinLock(&lock_handle);
status = STATUS_INVALID_PARAMETER;
DEBUG_ERROR("failed to set queue time; invalid "
"value", status);
goto windivert_ioctl_exit;
}
context->packet_queue_maxcounts =
(ULONGLONG)value * counts_per_ms;
context->packet_queue_maxtime = (ULONG)value;
break;
case WINDIVERT_PARAM_QUEUE_SIZE:
if (value < WINDIVERT_PARAM_QUEUE_SIZE_MIN ||
value > WINDIVERT_PARAM_QUEUE_SIZE_MAX)
{
KeReleaseInStackQueuedSpinLock(&lock_handle);
status = STATUS_INVALID_PARAMETER;
DEBUG_ERROR("failed to set queue size; invalid "
"value", status);
goto windivert_ioctl_exit;
}
context->packet_queue_maxsize = (ULONG)value;
break;
default:
KeReleaseInStackQueuedSpinLock(&lock_handle);
status = STATUS_INVALID_PARAMETER;
DEBUG_ERROR("failed to set parameter; invalid parameter",
status);
goto windivert_ioctl_exit;
}
KeReleaseInStackQueuedSpinLock(&lock_handle);
break;
case IOCTL_WINDIVERT_GET_PARAM:
ioctl = (windivert_ioctl_t)inbuf;
if (outbuflen != sizeof(UINT64))
{
status = STATUS_INVALID_PARAMETER;
DEBUG_ERROR("failed to get parameter; invalid output "
"buffer size", status);
goto windivert_ioctl_exit;
}
valptr = (UINT64 *)outbuf;
KeAcquireInStackQueuedSpinLock(&context->lock, &lock_handle);
if (context->state != WINDIVERT_CONTEXT_STATE_OPEN)
{
KeReleaseInStackQueuedSpinLock(&lock_handle);
status = STATUS_INVALID_DEVICE_STATE;
goto windivert_ioctl_exit;
}
switch ((WINDIVERT_PARAM)ioctl->arg8)
{
case WINDIVERT_PARAM_QUEUE_LEN:
*valptr = context->packet_queue_maxlength;
break;
case WINDIVERT_PARAM_QUEUE_TIME:
*valptr = context->packet_queue_maxtime;
break;
case WINDIVERT_PARAM_QUEUE_SIZE:
*valptr = context->packet_queue_maxsize;
break;
default:
KeReleaseInStackQueuedSpinLock(&lock_handle);
status = STATUS_INVALID_PARAMETER;
DEBUG_ERROR("failed to get parameter; invalid parameter",
status);
goto windivert_ioctl_exit;
}
KeReleaseInStackQueuedSpinLock(&lock_handle);
break;
default:
status = STATUS_INVALID_DEVICE_REQUEST;
DEBUG_ERROR("failed to complete I/O control; invalid request",
status);
break;
}
windivert_ioctl_exit:
WdfRequestComplete(request, status);
}
/*
* WinDivert notify callout.
*/
static NTSTATUS windivert_notify_callout(IN FWPS_CALLOUT_NOTIFY_TYPE type,
IN const GUID *filter_key, IN const FWPS_FILTER0 *filter)
{
UNREFERENCED_PARAMETER(type);
UNREFERENCED_PARAMETER(filter_key);
UNREFERENCED_PARAMETER(filter);
return STATUS_SUCCESS;
}
/*
* WinDivert classify outbound IPv4 callout.
*/
static void windivert_classify_outbound_network_v4_callout(
IN const FWPS_INCOMING_VALUES0 *fixed_vals,
IN const FWPS_INCOMING_METADATA_VALUES0 *meta_vals, IN OUT void *data,
const FWPS_FILTER0 *filter, IN UINT64 flow_context,
OUT FWPS_CLASSIFY_OUT0 *result)
{
windivert_classify_callout((context_t)filter->context,
WINDIVERT_DIRECTION_OUTBOUND,
fixed_vals->incomingValue[
FWPS_FIELD_OUTBOUND_IPPACKET_V4_INTERFACE_INDEX].value.uint32,
fixed_vals->incomingValue[
FWPS_FIELD_OUTBOUND_IPPACKET_V4_SUB_INTERFACE_INDEX].value.uint32,
TRUE,
(fixed_vals->incomingValue[
FWPS_FIELD_OUTBOUND_IPPACKET_V4_FLAGS].value.uint32 &
FWP_CONDITION_FLAG_IS_LOOPBACK) != 0,
0, data, flow_context, result);
}
/*
* WinDivert classify outbound IPv6 callout.
*/
static void windivert_classify_outbound_network_v6_callout(
IN const FWPS_INCOMING_VALUES0 *fixed_vals,
IN const FWPS_INCOMING_METADATA_VALUES0 *meta_vals, IN OUT void *data,
const FWPS_FILTER0 *filter, IN UINT64 flow_context,
OUT FWPS_CLASSIFY_OUT0 *result)
{
windivert_classify_callout((context_t)filter->context,
WINDIVERT_DIRECTION_OUTBOUND,
fixed_vals->incomingValue[
FWPS_FIELD_OUTBOUND_IPPACKET_V6_INTERFACE_INDEX].value.uint32,
fixed_vals->incomingValue[
FWPS_FIELD_OUTBOUND_IPPACKET_V6_SUB_INTERFACE_INDEX].value.uint32,
FALSE,
(fixed_vals->incomingValue[
FWPS_FIELD_OUTBOUND_IPPACKET_V6_FLAGS].value.uint32 &
FWP_CONDITION_FLAG_IS_LOOPBACK) != 0,
0, data, flow_context, result);
}
/*
* WinDivert classify inbound IPv4 callout.
*/
static void windivert_classify_inbound_network_v4_callout(
IN const FWPS_INCOMING_VALUES0 *fixed_vals,
IN const FWPS_INCOMING_METADATA_VALUES0 *meta_vals, IN OUT void *data,
const FWPS_FILTER0 *filter, IN UINT64 flow_context,
OUT FWPS_CLASSIFY_OUT0 *result)
{
UINT advance = meta_vals->ipHeaderSize;
windivert_classify_callout((context_t)filter->context,
WINDIVERT_DIRECTION_INBOUND,
fixed_vals->incomingValue[
FWPS_FIELD_INBOUND_IPPACKET_V4_INTERFACE_INDEX].value.uint32,
fixed_vals->incomingValue[
FWPS_FIELD_INBOUND_IPPACKET_V4_SUB_INTERFACE_INDEX].value.uint32,
TRUE,
(fixed_vals->incomingValue[
FWPS_FIELD_INBOUND_IPPACKET_V4_FLAGS].value.uint32 &
FWP_CONDITION_FLAG_IS_LOOPBACK) != 0,
advance, data, flow_context, result);
}
/*
* WinDivert classify inbound IPv6 callout.
*/
static void windivert_classify_inbound_network_v6_callout(
IN const FWPS_INCOMING_VALUES0 *fixed_vals,
IN const FWPS_INCOMING_METADATA_VALUES0 *meta_vals, IN OUT void *data,
const FWPS_FILTER0 *filter, IN UINT64 flow_context,
OUT FWPS_CLASSIFY_OUT0 *result)
{
UINT advance = meta_vals->ipHeaderSize;
windivert_classify_callout((context_t)filter->context,
WINDIVERT_DIRECTION_INBOUND,
fixed_vals->incomingValue[
FWPS_FIELD_INBOUND_IPPACKET_V6_INTERFACE_INDEX].value.uint32,
fixed_vals->incomingValue[
FWPS_FIELD_INBOUND_IPPACKET_V6_SUB_INTERFACE_INDEX].value.uint32,
FALSE,
(fixed_vals->incomingValue[
FWPS_FIELD_INBOUND_IPPACKET_V6_FLAGS].value.uint32 &
FWP_CONDITION_FLAG_IS_LOOPBACK) != 0,
advance, data, flow_context, result);
}
/*
* WinDivert classify forward IPv4 callout.
*/
static void windivert_classify_forward_network_v4_callout(
IN const FWPS_INCOMING_VALUES0 *fixed_vals,
IN const FWPS_INCOMING_METADATA_VALUES0 *meta_vals, IN OUT void *data,
const FWPS_FILTER0 *filter, IN UINT64 flow_context,
OUT FWPS_CLASSIFY_OUT0 *result)
{
windivert_classify_callout((context_t)filter->context,
WINDIVERT_DIRECTION_OUTBOUND,
fixed_vals->incomingValue[
FWPS_FIELD_IPFORWARD_V4_DESTINATION_INTERFACE_INDEX].value.uint32,
0, TRUE, FALSE, 0, data, flow_context, result);
}
/*
* WinDivert classify forward IPv6 callout.
*/
static void windivert_classify_forward_network_v6_callout(
IN const FWPS_INCOMING_VALUES0 *fixed_vals,
IN const FWPS_INCOMING_METADATA_VALUES0 *meta_vals, IN OUT void *data,
const FWPS_FILTER0 *filter, IN UINT64 flow_context,
OUT FWPS_CLASSIFY_OUT0 *result)
{
windivert_classify_callout((context_t)filter->context,
WINDIVERT_DIRECTION_OUTBOUND,
fixed_vals->incomingValue[
FWPS_FIELD_IPFORWARD_V6_DESTINATION_INTERFACE_INDEX].value.uint32,
0, FALSE, FALSE, 0, data, flow_context, result);
}
/*
* WinDivert classify callout.
*/
static void windivert_classify_callout(context_t context, IN UINT8 direction,
IN UINT32 if_idx, IN UINT32 sub_if_idx, IN BOOL isipv4, IN BOOL isloopback,
IN UINT advance, IN OUT void *data, IN UINT64 flow_context,
OUT FWPS_CLASSIFY_OUT0 *result)
{
KLOCK_QUEUE_HANDLE lock_handle;
FWPS_PACKET_INJECTION_STATE packet_state;
HANDLE packet_context;
UINT32 priority, packet_priority;
PNET_BUFFER_LIST buffers;
PNET_BUFFER buffer, buffer_fst, buffer_itr;
NDIS_TCP_IP_CHECKSUM_NET_BUFFER_LIST_INFO checksums_info;
UINT8 checksums;
BOOL outbound, hop;
WDFOBJECT object;
work_t work;
PLIST_ENTRY old_entry;
filter_t filter;
ULONGLONG timestamp;
NTSTATUS status;
// Basic checks:
if (!(result->rights & FWPS_RIGHT_ACTION_WRITE) || data == NULL)
{
return;
}
buffers = (PNET_BUFFER_LIST)data;
buffer = NET_BUFFER_LIST_FIRST_NB(buffers);
if (NET_BUFFER_LIST_NEXT_NBL(buffers) != NULL)
{
// This is a fragment group. This can be ignored since each fragment
// should have already been indicated.
result->actionType = FWP_ACTION_CONTINUE;
return;
}
if (isipv4)
{
packet_state = FwpsQueryPacketInjectionState0(inject_handle, buffers,
&packet_context);
}
else
{
packet_state = FwpsQueryPacketInjectionState0(injectv6_handle,
buffers, &packet_context);
}
KeAcquireInStackQueuedSpinLock(&context->lock, &lock_handle);
if (context->state != WINDIVERT_CONTEXT_STATE_OPEN)
{
KeReleaseInStackQueuedSpinLock(&lock_handle);
result->actionType = FWP_ACTION_CONTINUE;
return;
}
priority = context->priority;
filter = context->filter;
object = (WDFOBJECT)context->object;
WdfObjectReference(object);
KeReleaseInStackQueuedSpinLock(&lock_handle);
hop = FALSE;
if (packet_state == FWPS_PACKET_INJECTED_BY_SELF ||
packet_state == FWPS_PACKET_PREVIOUSLY_INJECTED_BY_SELF)
{
packet_priority = (UINT32)packet_context;
if (packet_priority >= priority)
{
WdfObjectDereference(object);
result->actionType = FWP_ACTION_CONTINUE;
return;
}
}
else if (packet_state == FWPS_PACKET_INJECTED_BY_OTHER)
{
// This is a packet injected by another driver, possibly an older
// version of WinDivert. To prevent block-clone-reinject infinite
// loops, we consider this capture to be a "hop".
hop = TRUE;
}
timestamp = (ULONGLONG)KeQueryPerformanceCounter(NULL).QuadPart;
timestamp = (timestamp > 0? timestamp-1: timestamp);
// Determine which checksum fields are present or not.
if (isloopback)
{
// Loopback packets appear to have bogus checksums, so do not trust.
checksums = 0;
}
else if (direction == WINDIVERT_DIRECTION_OUTBOUND)
{
checksums_info.Value = NET_BUFFER_LIST_INFO(buffers,
TcpIpChecksumNetBufferListInfo);
checksums =
(isipv4? 0: WINDIVERT_IP_CHECKSUM) |
(checksums_info.Transmit.TcpChecksum? 0: WINDIVERT_TCP_CHECKSUM) |
(checksums_info.Transmit.UdpChecksum? 0: WINDIVERT_UDP_CHECKSUM);
}
else
{
checksums = WINDIVERT_ALL_CHECKSUMS;
}
if (hop && isipv4)
{
checksums &= ~WINDIVERT_IP_CHECKSUM;
}
// Retreat the NET_BUFFER to the IP header, if necessary.
// If (advance != 0) then this must be in the inbound path, and the
// NET_BUFFER_LIST must contain exactly one NET_BUFFER.
if (advance != 0)
{
status = NdisRetreatNetBufferDataStart(buffer, advance, 0, NULL);
if (!NT_SUCCESS(status))
{
WdfObjectDereference(object);
result->actionType = FWP_ACTION_CONTINUE;
return;
}
}
/*
* This code is complicated by the fact the a single NET_BUFFER_LIST
* may contain several NET_BUFFER structures. Each NET_BUFFER needs to
* be filtered independently. To achieve this we do the following:
* 1) First check if any NET_BUFFER passes the filter.
* 2) If no, then CONTINUE the entire NET_BUFFER_LIST.
* 3) Else, split the NET_BUFFER_LIST into individual NET_BUFFERs; and
* either queue or re-inject based on the filter. This step is done
* out-of-band, see windivert_worker().
*/
// Find the first NET_BUFFER we need to queue:
buffer_fst = buffer;
outbound = (direction == WINDIVERT_DIRECTION_OUTBOUND);
do
{
BOOL match = windivert_filter(buffer_fst, if_idx, sub_if_idx, outbound,
isipv4, hop, checksums, filter);
if (match)
{
break;
}
buffer_fst = NET_BUFFER_NEXT_NB(buffer_fst);
}
while (buffer_fst != NULL);
if (advance != 0)
{
NdisAdvanceNetBufferDataStart(buffer, advance, FALSE, NULL);
}
if (buffer_fst == NULL)
{
// No packet matches the filter; continue the entire NET_BUFFER_LIST.
WdfObjectDereference(object);
result->actionType = FWP_ACTION_CONTINUE;
return;
}
// At least one packet matches the filter. Delay all further processing
// until windivert_worker() at IRQL=PASSIVE_LEVEL.
work = (work_t)windivert_malloc(sizeof(struct work_s), FALSE);
if (work == NULL)
{
goto windivert_classify_callout_exit;
}
FwpsReferenceNetBufferList(buffers, TRUE);
work->buffers = buffers;
work->buffer = buffer_fst;
work->advance = advance;
work->is_ipv4 = isipv4;
work->hop = hop;
work->checksums = checksums;
work->direction = direction;
work->if_idx = if_idx;
work->sub_if_idx = sub_if_idx;
work->priority = priority;
work->timestamp = timestamp;
old_entry = NULL;
KeAcquireInStackQueuedSpinLock(&context->lock, &lock_handle);
if (context->state != WINDIVERT_CONTEXT_STATE_OPEN)
{
KeReleaseInStackQueuedSpinLock(&lock_handle);
WdfObjectDereference(object);
FwpsDereferenceNetBufferList(buffers, FALSE);
windivert_free(work);
result->actionType = FWP_ACTION_CONTINUE;
return;
}
context->work_queue_length++;
if (context->work_queue_length > WINDIVERT_WORK_QUEUE_LEN_MAX)
{
old_entry = RemoveHeadList(&context->work_queue);
context->work_queue_length--;
}
InsertTailList(&context->work_queue, &work->entry);
WdfWorkItemEnqueue(context->workers[context->worker_curr]);
context->worker_curr =
(context->worker_curr + 1) % WINDIVERT_CONTEXT_MAXWORKERS;
KeReleaseInStackQueuedSpinLock(&lock_handle);
if (old_entry != NULL)
{
work = CONTAINING_RECORD(old_entry, struct work_s, entry);
FwpsDereferenceNetBufferList(work->buffers, FALSE);
windivert_free(work);
}
windivert_classify_callout_exit:
WdfObjectDereference(object);
result->actionType = FWP_ACTION_BLOCK;
result->flags |= FWPS_CLASSIFY_OUT_FLAG_ABSORB;
result->rights &= ~FWPS_RIGHT_ACTION_WRITE;
}
/*
* WinDivert work item routine for out-of-band filtering.
*/
VOID windivert_worker(IN WDFWORKITEM item)
{
KLOCK_QUEUE_HANDLE lock_handle;
WDFFILEOBJECT object = (WDFFILEOBJECT)WdfWorkItemGetParentObject(item);
PLIST_ENTRY entry;
work_t work;
context_t context = windivert_context_get(object);
PNET_BUFFER_LIST buffers_clone;
PNET_BUFFER buffer_itr, buffer_fst;
UINT advance;
BOOL match, ok, outbound, sniff_mode, forward;
filter_t filter;
NTSTATUS status;
KeAcquireInStackQueuedSpinLock(&context->lock, &lock_handle);
if (context->state == WINDIVERT_CONTEXT_STATE_OPEN)
{
sniff_mode = ((context->flags & WINDIVERT_FLAG_SNIFF) != 0);
forward = (context->layer == WINDIVERT_LAYER_NETWORK_FORWARD);
filter = context->filter;
}
while (context->state == WINDIVERT_CONTEXT_STATE_OPEN &&
!IsListEmpty(&context->work_queue))
{
entry = RemoveHeadList(&context->work_queue);
context->work_queue_length--;
KeReleaseInStackQueuedSpinLock(&lock_handle);
work = CONTAINING_RECORD(entry, struct work_s, entry);
advance = work->advance;
buffer_fst = work->buffer;
if (advance != 0)
{
status = NdisRetreatNetBufferDataStart(buffer_fst, advance, 0,
NULL);
if (!NT_SUCCESS(status))
{
advance = 0;
goto windivert_worker_complete;
}
}
if (!sniff_mode)
{
// In non-SNIFF mode, reinject all non-matching packets up to the
// first matching packet.
buffer_itr = NET_BUFFER_LIST_FIRST_NB(work->buffers);
while (buffer_itr != buffer_fst)
{
ok = windivert_reinject_packet(sniff_mode, forward,
work->direction, work->is_ipv4, work->if_idx,
work->sub_if_idx, work->priority, work->buffers,
buffer_itr);
if (!ok)
{
goto windivert_worker_complete;
}
buffer_itr = NET_BUFFER_NEXT_NB(buffer_itr);
}
}
else
{
// In SNIFF mode, reinject the entire NET_BUFFER_LIST.
ok = windivert_reinject_packet(sniff_mode, forward,
work->direction, work->is_ipv4, work->if_idx,
work->sub_if_idx, work->priority, work->buffers, NULL);
if (!ok)
{
goto windivert_worker_complete;
}
buffer_itr = buffer_fst;
}
// Queue the first matching packet.
ok = windivert_queue_packet(context, buffer_itr, work->direction,
work->if_idx, work->sub_if_idx, work->hop, work->checksums,
work->timestamp);
if (!ok)
{
goto windivert_worker_complete;
}
buffer_itr = NET_BUFFER_NEXT_NB(buffer_itr);
// Queue or re-inject all remaining packets.
outbound = (work->direction == WINDIVERT_DIRECTION_OUTBOUND);
while (buffer_itr != NULL)
{
match = windivert_filter(buffer_itr, work->if_idx,
work->sub_if_idx, outbound, work->is_ipv4, work->hop,
work->checksums, filter);
if (match)
{
ok = windivert_queue_packet(context, buffer_itr,
work->direction, work->if_idx, work->sub_if_idx,
work->hop, work->checksums, work->timestamp);
}
else
{
ok = windivert_reinject_packet(sniff_mode, forward,
work->direction, work->is_ipv4, work->if_idx,
work->sub_if_idx, work->priority, work->buffers,
buffer_itr);
}
if (!ok)
{
goto windivert_worker_complete;
}
buffer_itr = NET_BUFFER_NEXT_NB(buffer_itr);
}
windivert_worker_complete:
if (advance != 0)
{
NdisAdvanceNetBufferDataStart(work->buffer, advance, 0, 0);
}
FwpsDereferenceNetBufferList(work->buffers, FALSE);
windivert_free(work);
KeAcquireInStackQueuedSpinLock(&context->lock, &lock_handle);
}
KeReleaseInStackQueuedSpinLock(&lock_handle);
}
/*
* Queue a NET_BUFFER.
*/
static BOOL windivert_queue_packet(context_t context, PNET_BUFFER buffer,
UINT8 direction, UINT32 if_idx, UINT32 sub_if_idx, BOOL hop,
UINT8 checksums, ULONGLONG timestamp0)
{
KLOCK_QUEUE_HANDLE lock_handle;
PVOID data;
WDFREQUEST request;
PLIST_ENTRY entry, old_entry;
packet_t packet, old_packet;
UINT data_len;
ULONGLONG timestamp;
BOOL timeout;
NTSTATUS status;
// First we attempt to immediately service a read request directly without
// queuing the packet. This helps reduce overhead where possible.
timeout = FALSE;
request = NULL;
timestamp = (ULONGLONG)KeQueryPerformanceCounter(NULL).QuadPart;
KeAcquireInStackQueuedSpinLock(&context->lock, &lock_handle);
if (context->state != WINDIVERT_CONTEXT_STATE_OPEN)
{
KeReleaseInStackQueuedSpinLock(&lock_handle);
return FALSE;
}
if ((context->flags & WINDIVERT_FLAG_DROP) != 0)
{
KeReleaseInStackQueuedSpinLock(&lock_handle);
return TRUE;
}
timeout = (timestamp - timestamp0 > context->packet_queue_maxcounts);
if (!timeout && IsListEmpty(&context->packet_queue))
{
status = WdfIoQueueRetrieveNextRequest(context->read_queue, &request);
if (!NT_SUCCESS(status))
{
request = NULL;
}
}
KeReleaseInStackQueuedSpinLock(&lock_handle);
if (timeout)
{
return TRUE;
}
if (request != NULL)
{
// FAST PATH: Service an I/O request without queueing the packet.
windivert_read_service_request(NULL, buffer, direction, if_idx,
sub_if_idx, hop, checksums, request);
return TRUE;
}
// SLOW PATH: queue the packet.
data_len = NET_BUFFER_DATA_LENGTH(buffer);
packet = (packet_t)windivert_malloc(sizeof(struct packet_s), FALSE);
if (packet == NULL)
{
return FALSE;
}
packet->data = windivert_malloc(data_len, TRUE);
if (packet->data == NULL)
{
windivert_free_packet(packet);
return FALSE;
}
packet->data_len = data_len;
data = NdisGetDataBuffer(buffer, data_len, NULL, 1, 0);
if (data == NULL)
{
NdisGetDataBuffer(buffer, data_len, packet->data, 1, 0);
}
else
{
RtlCopyMemory(packet->data, data, data_len);
}
packet->hop = hop;
packet->checksums = checksums;
packet->direction = direction;
packet->if_idx = if_idx;
packet->sub_if_idx = sub_if_idx;
packet->timestamp = timestamp0;
entry = &packet->entry;
timestamp = (ULONGLONG)KeQueryPerformanceCounter(NULL).QuadPart;
KeAcquireInStackQueuedSpinLock(&context->lock, &lock_handle);
while (TRUE)
{
if (context->state != WINDIVERT_CONTEXT_STATE_OPEN)
{
KeReleaseInStackQueuedSpinLock(&lock_handle);
windivert_free_packet(packet);
return FALSE;
}
if (data_len > context->packet_queue_maxsize)
{
// (Corner case) the packet is larger than the max queue size:
KeReleaseInStackQueuedSpinLock(&lock_handle);
windivert_free_packet(packet);
return TRUE;
}
timeout = (timestamp - packet->timestamp >
context->packet_queue_maxcounts);
if (timeout)
{
// (Corner case) the packet has already expired:
KeReleaseInStackQueuedSpinLock(&lock_handle);
windivert_free_packet(packet);
return TRUE;
}
if (context->packet_queue_size + data_len >
context->packet_queue_maxsize ||
context->packet_queue_length + 1 > context->packet_queue_maxlength)
{
// The queue is full; drop a packet & try again:
old_entry = RemoveHeadList(&context->packet_queue);
old_packet = CONTAINING_RECORD(old_entry, struct packet_s, entry);
context->packet_queue_length--;
context->packet_queue_size -= old_packet->data_len;
KeReleaseInStackQueuedSpinLock(&lock_handle);
DEBUG("DROP: packet queue is full, dropping packet");
windivert_free_packet(old_packet);
timestamp = (ULONGLONG)KeQueryPerformanceCounter(NULL).QuadPart;
KeAcquireInStackQueuedSpinLock(&context->lock, &lock_handle);
continue;
}
else
{
// Queue the packet:
InsertTailList(&context->packet_queue, entry);
context->packet_queue_length++;
context->packet_queue_size += data_len;
break;
}
}
KeReleaseInStackQueuedSpinLock(&lock_handle);
DEBUG("PACKET: diverting packet (packet=%p)", packet);
// Service any pending I/O request.
windivert_read_service(context);
return TRUE;
}
/*
* Re-inject a packet or packets.
*/
static BOOL windivert_reinject_packet(BOOL sniff_mode, BOOL forward,
UINT8 direction, BOOL isipv4, UINT32 if_idx, UINT32 sub_if_idx,
UINT32 priority, PNET_BUFFER_LIST buffers, PNET_BUFFER buffer)
{
PNET_BUFFER_LIST buffers_cpy;
HANDLE handle;
BOOL clone = FALSE;
FWPS_INJECT_COMPLETE0 completion = windivert_reinject_complete;
NTSTATUS status;
if (buffer != NULL)
{
// Re-inject a specific packet. Not applicable for SNIFF mode.
if (sniff_mode)
{
return TRUE;
}
status = FwpsAllocateNetBufferAndNetBufferList0(nbl_pool_handle, 0, 0,
NET_BUFFER_FIRST_MDL(buffer), NET_BUFFER_DATA_OFFSET(buffer),
NET_BUFFER_DATA_LENGTH(buffer), &buffers_cpy);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to create NET_BUFFER_LIST for injected packet",
status);
return FALSE;
}
if (forward || direction == WINDIVERT_DIRECTION_OUTBOUND)
{
NdisCopySendNetBufferListInfo(buffers_cpy, buffers);
}
else
{
NdisCopyReceiveNetBufferListInfo(buffers_cpy, buffers);
}
}
else
{
// Re-inject all packets for SNIFF mode.
status = FwpsAllocateCloneNetBufferList0(buffers, nbl_pool_handle,
nb_pool_handle, 0, &buffers_cpy);
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to clone NET_BUFFER_LIST for injected packets",
status);
return FALSE;
}
clone = TRUE;
completion = windivert_reinject_clone_complete;
}
handle = (isipv4? inject_handle: injectv6_handle);
FwpsReferenceNetBufferList(buffers, TRUE);
if (forward)
{
status = FwpsInjectForwardAsync0(handle, (HANDLE)priority, 0,
(isipv4? AF_INET: AF_INET6), UNSPECIFIED_COMPARTMENT_ID,
if_idx, buffers_cpy, completion, (HANDLE)buffers);
}
else if (direction == WINDIVERT_DIRECTION_OUTBOUND)
{
status = FwpsInjectNetworkSendAsync0(handle,
(HANDLE)priority, 0, UNSPECIFIED_COMPARTMENT_ID, buffers_cpy,
completion, (HANDLE)buffers);
}
else
{
status = FwpsInjectNetworkReceiveAsync0(handle,
(HANDLE)priority, 0, UNSPECIFIED_COMPARTMENT_ID, if_idx,
sub_if_idx, buffers_cpy, completion, (HANDLE)buffers);
}
if (!NT_SUCCESS(status))
{
DEBUG_ERROR("failed to (re)inject packet(s)", status);
if (clone)
{
FwpsFreeNetBufferList0(buffers_cpy);
}
else
{
FwpsFreeCloneNetBufferList0(buffers_cpy, 0);
}
FwpsDereferenceNetBufferList(buffers, FALSE);
}
return TRUE;
}
/*
* WinDivert (re)inject complete.
*/
static void NTAPI windivert_reinject_complete(VOID *context,
NET_BUFFER_LIST *buffers_cpy, BOOLEAN dispatch_level)
{
PNET_BUFFER_LIST buffers = (PNET_BUFFER_LIST)context;
FwpsFreeNetBufferList0(buffers_cpy);
FwpsDereferenceNetBufferList(buffers, dispatch_level);
}
/*
* WinDivert (re)inject complete.
*/
static void NTAPI windivert_reinject_clone_complete(VOID *context,
NET_BUFFER_LIST *buffers_cpy, BOOLEAN dispatch_level)
{
PNET_BUFFER_LIST buffers = (PNET_BUFFER_LIST)context;
FwpsFreeCloneNetBufferList0(buffers_cpy, 0);
FwpsDereferenceNetBufferList(buffers, dispatch_level);
}
/*
* Free a packet.
*/
static void windivert_free_packet(packet_t packet)
{
windivert_free(packet->data);
windivert_free(packet);
}
/*
* Skip well-known IPv6 extension headers.
*/
static UINT8 windivert_skip_headers(UINT8 proto, UINT8 **header, size_t *len)
{
size_t hdrlen;
while (TRUE)
{
if (*len <= 2)
{
return IPPROTO_NONE;
}
hdrlen = (size_t)*(*header + 1);
switch (proto)
{
case IPPROTO_FRAGMENT:
hdrlen = 8;
break;
case IPPROTO_AH:
hdrlen += 2;
hdrlen *= 4;
break;
case IPPROTO_HOPOPTS:
case IPPROTO_DSTOPTS:
case IPPROTO_ROUTING:
hdrlen++;
hdrlen *= 8;
break;
case IPPROTO_NONE:
return proto;
default:
return proto;
}
if (hdrlen >= *len)
{
return IPPROTO_NONE;
}
proto = **header;
*header += hdrlen;
*len -= hdrlen;
}
}
/*
* Zero the IP/TCP/UDP checksums and/or decrement the TTL (if required)
*/
static NTSTATUS windivert_finalize_packet(void *header, size_t len,
BOOL hop, UINT8 checksums)
{
struct iphdr *ip_header = (struct iphdr *)header;
struct ipv6hdr *ipv6_header = (struct ipv6hdr *)header;
size_t ip_header_len, trans_len;
void *trans_header;
struct tcphdr *tcp_header;
struct udphdr *udp_header;
UINT8 proto;
NTSTATUS status = STATUS_SUCCESS;
if (checksums == WINDIVERT_ALL_CHECKSUMS && !hop)
{
return status;
}
if (len < sizeof(struct iphdr))
{
return status;
}
switch (ip_header->Version)
{
case 4:
ip_header_len = ip_header->HdrLength*sizeof(UINT32);
if (len < ip_header_len)
{
return status;
}
if (hop)
{
if (ip_header->TTL <= 1)
{
status = STATUS_HOPLIMIT_EXCEEDED;
}
if (ip_header->TTL != 0)
{
ip_header->TTL--;
}
}
if ((checksums & WINDIVERT_IP_CHECKSUM) != 0)
{
ip_header->Checksum = 0;
}
proto = ip_header->Protocol;
trans_len = len - ip_header_len;
trans_header = (UINT8 *)ip_header + ip_header_len;
break;
case 6:
if (len < sizeof(struct ipv6hdr))
{
return status;
}
if (hop)
{
if (ipv6_header->HopLimit <= 1)
{
status = STATUS_HOPLIMIT_EXCEEDED;
}
if (ipv6_header->HopLimit != 0)
{
ipv6_header->HopLimit--;
}
}
trans_len = len - sizeof(struct ipv6hdr);
trans_header = (UINT8 *)(ipv6_header + 1);
// Skip extension headers:
proto = windivert_skip_headers(ipv6_header->NextHdr,
(UINT8 **)&trans_header, &trans_len);
break;
default:
return status;
}
switch (proto)
{
case IPPROTO_TCP:
if ((checksums & WINDIVERT_TCP_CHECKSUM) != 0)
{
return status;
}
tcp_header = (struct tcphdr *)trans_header;
if (trans_len < sizeof(struct tcphdr))
{
return status;
}
tcp_header->Checksum = 0;
break;
case IPPROTO_UDP:
if ((checksums & WINDIVERT_UDP_CHECKSUM) != 0)
{
return status;
}
udp_header = (struct udphdr *)trans_header;
if (trans_len < sizeof(struct udphdr))
{
return status;
}
udp_header->Checksum = 0;
break;
}
return status;
}
/*
* Big number comparison.
*/
static int windivert_big_num_compare(const UINT32 *a, const UINT32 *b)
{
if (a[3] < b[3])
{
return -1;
}
if (a[3] > b[3])
{
return 1;
}
if (a[2] < b[2])
{
return -1;
}
if (a[2] > b[2])
{
return 1;
}
if (a[1] < b[1])
{
return -1;
}
if (a[1] > b[1])
{
return 1;
}
if (a[0] < b[0])
{
return -1;
}
if (a[0] > b[0])
{
return 1;
}
return 0;
}
/*
* Checks if the given packet is of interest.
*/
static BOOL windivert_filter(PNET_BUFFER buffer, UINT32 if_idx,
UINT32 sub_if_idx, BOOL outbound, BOOL isipv4, BOOL hop, UINT8 checksums,
filter_t filter)
{
size_t tot_len, ip_header_len;
struct iphdr *ip_header = NULL;
struct ipv6hdr *ipv6_header = NULL;
struct icmphdr *icmp_header = NULL;
struct icmpv6hdr *icmpv6_header = NULL;
struct tcphdr *tcp_header = NULL;
struct udphdr *udp_header = NULL;
UINT16 ip, ttl;
UINT8 proto;
NTSTATUS status;
// Parse the headers:
tot_len = NET_BUFFER_DATA_LENGTH(buffer);
if (tot_len < sizeof(struct iphdr))
{
DEBUG("FILTER: REJECT (packet length too small)");
return FALSE;
}
// Get the IP header.
if (isipv4)
{
// IPv4:
if (tot_len < sizeof(struct iphdr))
{
DEBUG("FILTER: REJECT (packet length too small)");
return FALSE;
}
ip_header = (struct iphdr *)NdisGetDataBuffer(buffer,
sizeof(struct iphdr), NULL, 1, 0);
if (ip_header == NULL)
{
DEBUG("FILTER: REJECT (failed to get IPv4 header)");
return FALSE;
}
ip_header_len = ip_header->HdrLength*sizeof(UINT32);
if (ip_header->Version != 4 ||
RtlUshortByteSwap(ip_header->Length) != tot_len ||
ip_header->HdrLength < 5 ||
ip_header_len > tot_len)
{
DEBUG("FILTER: REJECT (bad IPv4 packet)");
return FALSE;
}
proto = ip_header->Protocol;
NdisAdvanceNetBufferDataStart(buffer, ip_header_len, FALSE, NULL);
}
else
{
// IPv6:
if (tot_len < sizeof(struct ipv6hdr))
{
DEBUG("FILTER: REJECT (packet length too small)");
return FALSE;
}
ipv6_header = (struct ipv6hdr *)NdisGetDataBuffer(buffer,
sizeof(struct ipv6hdr), NULL, 1, 0);
if (ipv6_header == NULL)
{
DEBUG("FILTER: REJECT (failed to get IPv6 header)");
return FALSE;
}
ip_header_len = sizeof(struct ipv6hdr);
if (ipv6_header->Version != 6 ||
ip_header_len > tot_len ||
RtlUshortByteSwap(ipv6_header->Length) +
sizeof(struct ipv6hdr) != tot_len)
{
DEBUG("FILTER: REJECT (bad IPv6 packet)");
return FALSE;
}
proto = ipv6_header->NextHdr;
NdisAdvanceNetBufferDataStart(buffer, ip_header_len, FALSE, NULL);
// Skip extension headers:
while (TRUE)
{
UINT8 *ext_header;
size_t ext_header_len;
BOOL isexthdr = TRUE;
ext_header = (UINT8 *)NdisGetDataBuffer(buffer, 2, NULL, 1, 0);
if (ext_header == NULL)
{
break;
}
ext_header_len = (size_t)ext_header[1];
switch (proto)
{
case IPPROTO_FRAGMENT:
ext_header_len = 8;
break;
case IPPROTO_AH:
ext_header_len += 2;
ext_header_len *= 4;
break;
case IPPROTO_HOPOPTS:
case IPPROTO_DSTOPTS:
case IPPROTO_ROUTING:
ext_header_len++;
ext_header_len *= 8;
break;
default:
isexthdr = FALSE;
break;
}
if (!isexthdr)
{
break;
}
proto = ext_header[0];
ip_header_len += ext_header_len;
NdisAdvanceNetBufferDataStart(buffer, ext_header_len, FALSE,
NULL);
}
}
switch (proto)
{
case IPPROTO_ICMP:
icmp_header = (struct icmphdr *)NdisGetDataBuffer(buffer,
sizeof(struct icmphdr), NULL, 1, 0);
break;
case IPPROTO_ICMPV6:
icmpv6_header = (struct icmpv6hdr *)NdisGetDataBuffer(buffer,
sizeof(struct icmpv6hdr), NULL, 1, 0);
break;
case IPPROTO_TCP:
tcp_header = (struct tcphdr *)NdisGetDataBuffer(buffer,
sizeof(struct tcphdr), NULL, 1, 0);
break;
case IPPROTO_UDP:
udp_header = (struct udphdr *)NdisGetDataBuffer(buffer,
sizeof(struct udphdr), NULL, 1, 0);
break;
default:
break;
}
status = NdisRetreatNetBufferDataStart(buffer, ip_header_len, 0, NULL);
if (!NT_SUCCESS(status))
{
// Should never occur.
DEBUG("FILTER: REJECT (failed to retreat buffer)");
return FALSE;
}
// Execute the filter:
ip = 0;
ttl = WINDIVERT_FILTER_MAXLEN+1; // Additional safety
while (ttl-- != 0)
{
BOOL result;
int cmp;
UINT32 field[4];
field[1] = 0;
field[2] = 0;
field[3] = 0;
switch (filter[ip].protocol)
{
case WINDIVERT_FILTER_PROTOCOL_NONE:
result = TRUE;
break;
case WINDIVERT_FILTER_PROTOCOL_IP:
result = (ip_header != NULL);
break;
case WINDIVERT_FILTER_PROTOCOL_IPV6:
result = (ipv6_header != NULL);
break;
case WINDIVERT_FILTER_PROTOCOL_ICMP:
result = (icmp_header != NULL);
break;
case WINDIVERT_FILTER_PROTOCOL_ICMPV6:
result = (icmpv6_header != NULL);
break;
case WINDIVERT_FILTER_PROTOCOL_TCP:
result = (tcp_header != NULL);
break;
case WINDIVERT_FILTER_PROTOCOL_UDP:
result = (udp_header != NULL);
break;
default:
result = FALSE;
break;
}
if (result)
{
switch (filter[ip].field)
{
case WINDIVERT_FILTER_FIELD_ZERO:
field[0] = 0;
break;
case WINDIVERT_FILTER_FIELD_INBOUND:
field[0] = (UINT32)(!outbound);
break;
case WINDIVERT_FILTER_FIELD_OUTBOUND:
field[0] = (UINT32)outbound;
break;
case WINDIVERT_FILTER_FIELD_IFIDX:
field[0] = (UINT32)if_idx;
break;
case WINDIVERT_FILTER_FIELD_SUBIFIDX:
field[0] = (UINT32)sub_if_idx;
break;
case WINDIVERT_FILTER_FIELD_IP:
field[0] = (UINT32)(ip_header != NULL);
break;
case WINDIVERT_FILTER_FIELD_IPV6:
field[0] = (UINT32)(ipv6_header != NULL);
break;
case WINDIVERT_FILTER_FIELD_ICMP:
field[0] = (UINT32)(icmp_header != NULL);
break;
case WINDIVERT_FILTER_FIELD_ICMPV6:
field[0] = (UINT32)(icmpv6_header != NULL);
break;
case WINDIVERT_FILTER_FIELD_TCP:
field[0] = (UINT32)(tcp_header != NULL);
break;
case WINDIVERT_FILTER_FIELD_UDP:
field[0] = (UINT32)(udp_header != NULL);
break;
case WINDIVERT_FILTER_FIELD_IP_HDRLENGTH:
field[0] = (UINT32)ip_header->HdrLength;
break;
case WINDIVERT_FILTER_FIELD_IP_TOS:
field[0] = (UINT32)ip_header->TOS;
break;
case WINDIVERT_FILTER_FIELD_IP_LENGTH:
field[0] = (UINT32)RtlUshortByteSwap(ip_header->Length);
break;
case WINDIVERT_FILTER_FIELD_IP_ID:
field[0] = (UINT32)RtlUshortByteSwap(ip_header->Id);
break;
case WINDIVERT_FILTER_FIELD_IP_DF:
field[0] = (UINT32)IPHDR_GET_DF(ip_header);
break;
case WINDIVERT_FILTER_FIELD_IP_MF:
field[0] = (UINT32)IPHDR_GET_MF(ip_header);
break;
case WINDIVERT_FILTER_FIELD_IP_FRAGOFF:
field[0] = (UINT32)RtlUshortByteSwap(
IPHDR_GET_FRAGOFF(ip_header));
break;
case WINDIVERT_FILTER_FIELD_IP_TTL:
field[0] = (UINT32)ip_header->TTL;
if (hop)
{
field[0] = (field[0] == 0? 0: field[0]-1);
}
break;
case WINDIVERT_FILTER_FIELD_IP_PROTOCOL:
field[0] = (UINT32)ip_header->Protocol;
break;
case WINDIVERT_FILTER_FIELD_IP_CHECKSUM:
if ((checksums & WINDIVERT_IP_CHECKSUM) != 0)
{
field[0] =
(UINT32)RtlUshortByteSwap(ip_header->Checksum);
}
else
{
field[0] = 0;
}
break;
case WINDIVERT_FILTER_FIELD_IP_SRCADDR:
field[0] = (UINT32)RtlUlongByteSwap(ip_header->SrcAddr);
break;
case WINDIVERT_FILTER_FIELD_IP_DSTADDR:
field[0] = (UINT32)RtlUlongByteSwap(ip_header->DstAddr);
break;
case WINDIVERT_FILTER_FIELD_IPV6_TRAFFICCLASS:
field[0] = (UINT32)IPV6HDR_GET_TRAFFICCLASS(ipv6_header);
break;
case WINDIVERT_FILTER_FIELD_IPV6_FLOWLABEL:
field[0] = (UINT32)RtlUlongByteSwap(
IPV6HDR_GET_FLOWLABEL(ipv6_header));
break;
case WINDIVERT_FILTER_FIELD_IPV6_LENGTH:
field[0] = (UINT32)RtlUshortByteSwap(ipv6_header->Length);
break;
case WINDIVERT_FILTER_FIELD_IPV6_NEXTHDR:
field[0] = (UINT32)ipv6_header->NextHdr;
break;
case WINDIVERT_FILTER_FIELD_IPV6_HOPLIMIT:
field[0] = (UINT32)ipv6_header->HopLimit;
if (hop)
{
field[0] = (field[0] == 0? 0: field[0]-1);
}
break;
case WINDIVERT_FILTER_FIELD_IPV6_SRCADDR:
field[3] =
(UINT32)RtlUlongByteSwap(ipv6_header->SrcAddr[0]);
field[2] =
(UINT32)RtlUlongByteSwap(ipv6_header->SrcAddr[1]);
field[1] =
(UINT32)RtlUlongByteSwap(ipv6_header->SrcAddr[2]);
field[0] =
(UINT32)RtlUlongByteSwap(ipv6_header->SrcAddr[3]);
break;
case WINDIVERT_FILTER_FIELD_IPV6_DSTADDR:
field[3] =
(UINT32)RtlUlongByteSwap(ipv6_header->DstAddr[0]);
field[2] =
(UINT32)RtlUlongByteSwap(ipv6_header->DstAddr[1]);
field[1] =
(UINT32)RtlUlongByteSwap(ipv6_header->DstAddr[2]);
field[0] =
(UINT32)RtlUlongByteSwap(ipv6_header->DstAddr[3]);
break;
case WINDIVERT_FILTER_FIELD_ICMP_TYPE:
field[0] = (UINT32)icmp_header->Type;
break;
case WINDIVERT_FILTER_FIELD_ICMP_CODE:
field[0] = (UINT32)icmp_header->Code;
break;
case WINDIVERT_FILTER_FIELD_ICMP_CHECKSUM:
field[0] =
(UINT32)RtlUshortByteSwap(icmp_header->Checksum);
break;
case WINDIVERT_FILTER_FIELD_ICMP_BODY:
field[0] = (UINT32)RtlUlongByteSwap(icmp_header->Body);
break;
case WINDIVERT_FILTER_FIELD_ICMPV6_TYPE:
field[0] = (UINT32)icmpv6_header->Type;
break;
case WINDIVERT_FILTER_FIELD_ICMPV6_CODE:
field[0] = (UINT32)icmpv6_header->Code;
break;
case WINDIVERT_FILTER_FIELD_ICMPV6_CHECKSUM:
field[0] =
(UINT32)RtlUshortByteSwap(icmpv6_header->Checksum);
break;
case WINDIVERT_FILTER_FIELD_ICMPV6_BODY:
field[0] =
(UINT32)RtlUlongByteSwap(icmpv6_header->Body);
break;
case WINDIVERT_FILTER_FIELD_TCP_SRCPORT:
field[0] = (UINT32)RtlUshortByteSwap(tcp_header->SrcPort);
break;
case WINDIVERT_FILTER_FIELD_TCP_DSTPORT:
field[0] = (UINT32)RtlUshortByteSwap(tcp_header->DstPort);
break;
case WINDIVERT_FILTER_FIELD_TCP_SEQNUM:
field[0] = (UINT32)RtlUlongByteSwap(tcp_header->SeqNum);
break;
case WINDIVERT_FILTER_FIELD_TCP_ACKNUM:
field[0] = (UINT32)RtlUlongByteSwap(tcp_header->AckNum);
break;
case WINDIVERT_FILTER_FIELD_TCP_HDRLENGTH:
field[0] = (UINT32)tcp_header->HdrLength;
break;
case WINDIVERT_FILTER_FIELD_TCP_URG:
field[0] = (UINT32)tcp_header->Urg;
break;
case WINDIVERT_FILTER_FIELD_TCP_ACK:
field[0] = (UINT32)tcp_header->Ack;
break;
case WINDIVERT_FILTER_FIELD_TCP_PSH:
field[0] = (UINT32)tcp_header->Psh;
break;
case WINDIVERT_FILTER_FIELD_TCP_RST:
field[0] = (UINT32)tcp_header->Rst;
break;
case WINDIVERT_FILTER_FIELD_TCP_SYN:
field[0] = (UINT32)tcp_header->Syn;
break;
case WINDIVERT_FILTER_FIELD_TCP_FIN:
field[0] = (UINT32)tcp_header->Fin;
break;
case WINDIVERT_FILTER_FIELD_TCP_WINDOW:
field[0] = (UINT32)RtlUshortByteSwap(tcp_header->Window);
break;
case WINDIVERT_FILTER_FIELD_TCP_CHECKSUM:
if ((checksums & WINDIVERT_TCP_CHECKSUM) != 0)
{
field[0] =
(UINT32)RtlUshortByteSwap(tcp_header->Checksum);
}
else
{
field[0] = 0;
}
break;
case WINDIVERT_FILTER_FIELD_TCP_URGPTR:
field[0] = (UINT32)RtlUshortByteSwap(tcp_header->UrgPtr);
break;
case WINDIVERT_FILTER_FIELD_TCP_PAYLOADLENGTH:
field[0] = (UINT32)(tot_len - ip_header_len -
tcp_header->HdrLength*sizeof(UINT32));
break;
case WINDIVERT_FILTER_FIELD_UDP_SRCPORT:
field[0] = (UINT32)RtlUshortByteSwap(udp_header->SrcPort);
break;
case WINDIVERT_FILTER_FIELD_UDP_DSTPORT:
field[0] = (UINT32)RtlUshortByteSwap(udp_header->DstPort);
break;
case WINDIVERT_FILTER_FIELD_UDP_LENGTH:
field[0] = (UINT32)RtlUshortByteSwap(udp_header->Length);
break;
case WINDIVERT_FILTER_FIELD_UDP_CHECKSUM:
if ((checksums & WINDIVERT_UDP_CHECKSUM) != 0)
{
field[0] =
(UINT32)RtlUshortByteSwap(udp_header->Checksum);
}
else
{
field[0] = 0;
}
break;
case WINDIVERT_FILTER_FIELD_UDP_PAYLOADLENGTH:
field[0] = (UINT32)(tot_len - ip_header_len -
sizeof(struct udphdr));
break;
default:
field[0] = 0;
break;
}
cmp = windivert_big_num_compare(field, filter[ip].arg);
switch (filter[ip].test)
{
case WINDIVERT_FILTER_TEST_EQ:
result = (cmp == 0);
break;
case WINDIVERT_FILTER_TEST_NEQ:
result = (cmp != 0);
break;
case WINDIVERT_FILTER_TEST_LT:
result = (cmp < 0);
break;
case WINDIVERT_FILTER_TEST_LEQ:
result = (cmp <= 0);
break;
case WINDIVERT_FILTER_TEST_GT:
result = (cmp > 0);
break;
case WINDIVERT_FILTER_TEST_GEQ:
result = (cmp >= 0);
break;
default:
result = FALSE;
break;
}
}
ip = (result? filter[ip].success: filter[ip].failure);
if (ip == WINDIVERT_FILTER_RESULT_ACCEPT)
{
return TRUE;
}
if (ip == WINDIVERT_FILTER_RESULT_REJECT)
{
return FALSE;
}
}
DEBUG("FILTER: REJECT (filter TTL exceeded)");
return FALSE;
}
/*
* Analyze the given filter.
*/
static void windivert_filter_analyze(filter_t filter, BOOL *is_inbound,
BOOL *is_outbound, BOOL *is_ipv4, BOOL *is_ipv6)
{
BOOL result;
// False filter?
result = windivert_filter_test(filter, 0, WINDIVERT_FILTER_PROTOCOL_NONE,
WINDIVERT_FILTER_FIELD_ZERO, 0);
if (!result)
{
*is_inbound = FALSE;
*is_outbound = FALSE;
*is_ipv4 = FALSE;
*is_ipv6 = FALSE;
return;
}
// Inbound?
result = windivert_filter_test(filter, 0, WINDIVERT_FILTER_PROTOCOL_NONE,
WINDIVERT_FILTER_FIELD_INBOUND, 1);
if (result)
{
result = windivert_filter_test(filter, 0,
WINDIVERT_FILTER_PROTOCOL_NONE, WINDIVERT_FILTER_FIELD_OUTBOUND,
0);
}
*is_inbound = result;
// Outbound?
result = windivert_filter_test(filter, 0, WINDIVERT_FILTER_PROTOCOL_NONE,
WINDIVERT_FILTER_FIELD_OUTBOUND, 1);
if (result)
{
result = windivert_filter_test(filter, 0,
WINDIVERT_FILTER_PROTOCOL_NONE, WINDIVERT_FILTER_FIELD_INBOUND, 0);
}
*is_outbound = result;
// IPv4?
result = windivert_filter_test(filter, 0, WINDIVERT_FILTER_PROTOCOL_NONE,
WINDIVERT_FILTER_FIELD_IP, 1);
if (result)
{
result = windivert_filter_test(filter, 0,
WINDIVERT_FILTER_PROTOCOL_NONE, WINDIVERT_FILTER_FIELD_IPV6, 0);
}
*is_ipv4 = result;
// Ipv6?
result = windivert_filter_test(filter, 0, WINDIVERT_FILTER_PROTOCOL_NONE,
WINDIVERT_FILTER_FIELD_IPV6, 1);
if (result)
{
result = windivert_filter_test(filter, 0,
WINDIVERT_FILTER_PROTOCOL_NONE, WINDIVERT_FILTER_FIELD_IP, 0);
}
*is_ipv6 = result;
}
/*
* Test a filter for any packet where field = arg.
*/
static BOOL windivert_filter_test(filter_t filter, UINT16 ip, UINT8 protocol,
UINT8 field, UINT32 arg)
{
BOOL known = FALSE;
BOOL result = FALSE;
if (ip == WINDIVERT_FILTER_RESULT_ACCEPT)
{
return TRUE;
}
if (ip == WINDIVERT_FILTER_RESULT_REJECT)
{
return FALSE;
}
if (ip > WINDIVERT_FILTER_MAXLEN)
{
return FALSE;
}
if (filter[ip].protocol == protocol &&
filter[ip].field == field)
{
known = TRUE;
switch (filter[ip].test)
{
case WINDIVERT_FILTER_TEST_EQ:
result = (arg == filter[ip].arg[0]);
break;
case WINDIVERT_FILTER_TEST_NEQ:
result = (arg != filter[ip].arg[0]);
break;
case WINDIVERT_FILTER_TEST_LT:
result = (arg < filter[ip].arg[0]);
break;
case WINDIVERT_FILTER_TEST_LEQ:
result = (arg <= filter[ip].arg[0]);
break;
case WINDIVERT_FILTER_TEST_GT:
result = (arg > filter[ip].arg[0]);
break;
case WINDIVERT_FILTER_TEST_GEQ:
result = (arg >= filter[ip].arg[0]);
break;
default:
result = FALSE;
break;
}
}
if (!known)
{
result = windivert_filter_test(filter, filter[ip].success, protocol,
field, arg);
if (result)
{
return TRUE;
}
return windivert_filter_test(filter, filter[ip].failure, protocol,
field, arg);
}
else
{
ip = (result? filter[ip].success: filter[ip].failure);
return windivert_filter_test(filter, ip, protocol, field, arg);
}
}
/*
* Compile a WinDivert filter from an IOCTL.
*/
static filter_t windivert_filter_compile(windivert_ioctl_filter_t ioctl_filter,
size_t ioctl_filter_len)
{
filter_t filter0 = NULL, result = NULL;
UINT16 i;
size_t length;
if (ioctl_filter_len % sizeof(struct windivert_ioctl_filter_s) != 0)
{
goto windivert_filter_compile_exit;
}
length = ioctl_filter_len / sizeof(struct windivert_ioctl_filter_s);
if (length >= WINDIVERT_FILTER_MAXLEN)
{
goto windivert_filter_compile_exit;
}
// Do NOT use the stack (size = 12Kb on x86) for filter0.
filter0 = (filter_t)windivert_malloc(
WINDIVERT_FILTER_MAXLEN*sizeof(struct filter_s), TRUE);
if (filter0 == NULL)
{
goto windivert_filter_compile_exit;
}
for (i = 0; i < length; i++)
{
if (ioctl_filter[i].field > WINDIVERT_FILTER_FIELD_MAX ||
ioctl_filter[i].test > WINDIVERT_FILTER_TEST_MAX)
{
goto windivert_filter_compile_exit;
}
switch (ioctl_filter[i].success)
{
case WINDIVERT_FILTER_RESULT_ACCEPT:
case WINDIVERT_FILTER_RESULT_REJECT:
break;
default:
if (ioctl_filter[i].success <= i ||
ioctl_filter[i].success >= length)
{
goto windivert_filter_compile_exit;
}
break;
}
switch (ioctl_filter[i].failure)
{
case WINDIVERT_FILTER_RESULT_ACCEPT:
case WINDIVERT_FILTER_RESULT_REJECT:
break;
default:
if (ioctl_filter[i].failure <= i ||
ioctl_filter[i].failure >= length)
{
goto windivert_filter_compile_exit;
}
break;
}
// Enforce size limits:
if (ioctl_filter[i].field != WINDIVERT_FILTER_FIELD_IPV6_SRCADDR &&
ioctl_filter[i].field != WINDIVERT_FILTER_FIELD_IPV6_DSTADDR)
{
if (ioctl_filter[i].arg[1] != 0 ||
ioctl_filter[i].arg[2] != 0 ||
ioctl_filter[i].arg[3] != 0)
{
goto windivert_filter_compile_exit;
}
}
switch (ioctl_filter[i].field)
{
case WINDIVERT_FILTER_FIELD_ZERO:
case WINDIVERT_FILTER_FIELD_INBOUND:
case WINDIVERT_FILTER_FIELD_OUTBOUND:
case WINDIVERT_FILTER_FIELD_IP:
case WINDIVERT_FILTER_FIELD_IPV6:
case WINDIVERT_FILTER_FIELD_ICMP:
case WINDIVERT_FILTER_FIELD_ICMPV6:
case WINDIVERT_FILTER_FIELD_TCP:
case WINDIVERT_FILTER_FIELD_UDP:
case WINDIVERT_FILTER_FIELD_IP_DF:
case WINDIVERT_FILTER_FIELD_IP_MF:
case WINDIVERT_FILTER_FIELD_TCP_URG:
case WINDIVERT_FILTER_FIELD_TCP_ACK:
case WINDIVERT_FILTER_FIELD_TCP_PSH:
case WINDIVERT_FILTER_FIELD_TCP_RST:
case WINDIVERT_FILTER_FIELD_TCP_SYN:
case WINDIVERT_FILTER_FIELD_TCP_FIN:
if (ioctl_filter[i].arg[0] > 1)
{
goto windivert_filter_compile_exit;
}
break;
case WINDIVERT_FILTER_FIELD_IP_HDRLENGTH:
case WINDIVERT_FILTER_FIELD_TCP_HDRLENGTH:
if (ioctl_filter[i].arg[0] > 0x0F)
{
goto windivert_filter_compile_exit;
}
break;
case WINDIVERT_FILTER_FIELD_IP_TOS:
case WINDIVERT_FILTER_FIELD_IP_TTL:
case WINDIVERT_FILTER_FIELD_IP_PROTOCOL:
case WINDIVERT_FILTER_FIELD_IPV6_TRAFFICCLASS:
case WINDIVERT_FILTER_FIELD_IPV6_NEXTHDR:
case WINDIVERT_FILTER_FIELD_IPV6_HOPLIMIT:
case WINDIVERT_FILTER_FIELD_ICMP_TYPE:
case WINDIVERT_FILTER_FIELD_ICMP_CODE:
case WINDIVERT_FILTER_FIELD_ICMPV6_TYPE:
case WINDIVERT_FILTER_FIELD_ICMPV6_CODE:
if (ioctl_filter[i].arg[0] > UINT8_MAX)
{
goto windivert_filter_compile_exit;
}
break;
case WINDIVERT_FILTER_FIELD_IP_FRAGOFF:
if (ioctl_filter[i].arg[0] > 0x1FFF)
{
goto windivert_filter_compile_exit;
}
break;
case WINDIVERT_FILTER_FIELD_IP_LENGTH:
case WINDIVERT_FILTER_FIELD_IP_ID:
case WINDIVERT_FILTER_FIELD_IP_CHECKSUM:
case WINDIVERT_FILTER_FIELD_IPV6_LENGTH:
case WINDIVERT_FILTER_FIELD_ICMP_CHECKSUM:
case WINDIVERT_FILTER_FIELD_ICMPV6_CHECKSUM:
case WINDIVERT_FILTER_FIELD_TCP_SRCPORT:
case WINDIVERT_FILTER_FIELD_TCP_DSTPORT:
case WINDIVERT_FILTER_FIELD_TCP_WINDOW:
case WINDIVERT_FILTER_FIELD_TCP_CHECKSUM:
case WINDIVERT_FILTER_FIELD_TCP_URGPTR:
case WINDIVERT_FILTER_FIELD_TCP_PAYLOADLENGTH:
case WINDIVERT_FILTER_FIELD_UDP_SRCPORT:
case WINDIVERT_FILTER_FIELD_UDP_DSTPORT:
case WINDIVERT_FILTER_FIELD_UDP_LENGTH:
case WINDIVERT_FILTER_FIELD_UDP_CHECKSUM:
case WINDIVERT_FILTER_FIELD_UDP_PAYLOADLENGTH:
if (ioctl_filter[i].arg[0] > UINT16_MAX)
{
goto windivert_filter_compile_exit;
}
break;
case WINDIVERT_FILTER_FIELD_IPV6_FLOWLABEL:
if (ioctl_filter[i].arg[0] > 0x000FFFFF)
{
goto windivert_filter_compile_exit;
}
break;
default:
break;
}
filter0[i].field = ioctl_filter[i].field;
filter0[i].test = ioctl_filter[i].test;
filter0[i].success = ioctl_filter[i].success;
filter0[i].failure = ioctl_filter[i].failure;
filter0[i].arg[0] = ioctl_filter[i].arg[0];
filter0[i].arg[1] = ioctl_filter[i].arg[1];
filter0[i].arg[2] = ioctl_filter[i].arg[2];
filter0[i].arg[3] = ioctl_filter[i].arg[3];
// Protocol selection:
switch (ioctl_filter[i].field)
{
case WINDIVERT_FILTER_FIELD_ZERO:
case WINDIVERT_FILTER_FIELD_INBOUND:
case WINDIVERT_FILTER_FIELD_OUTBOUND:
case WINDIVERT_FILTER_FIELD_IFIDX:
case WINDIVERT_FILTER_FIELD_SUBIFIDX:
case WINDIVERT_FILTER_FIELD_IP:
case WINDIVERT_FILTER_FIELD_IPV6:
case WINDIVERT_FILTER_FIELD_ICMP:
case WINDIVERT_FILTER_FIELD_ICMPV6:
case WINDIVERT_FILTER_FIELD_TCP:
case WINDIVERT_FILTER_FIELD_UDP:
filter0[i].protocol = WINDIVERT_FILTER_PROTOCOL_NONE;
break;
case WINDIVERT_FILTER_FIELD_IP_HDRLENGTH:
case WINDIVERT_FILTER_FIELD_IP_TOS:
case WINDIVERT_FILTER_FIELD_IP_LENGTH:
case WINDIVERT_FILTER_FIELD_IP_ID:
case WINDIVERT_FILTER_FIELD_IP_DF:
case WINDIVERT_FILTER_FIELD_IP_MF:
case WINDIVERT_FILTER_FIELD_IP_FRAGOFF:
case WINDIVERT_FILTER_FIELD_IP_TTL:
case WINDIVERT_FILTER_FIELD_IP_PROTOCOL:
case WINDIVERT_FILTER_FIELD_IP_CHECKSUM:
case WINDIVERT_FILTER_FIELD_IP_SRCADDR:
case WINDIVERT_FILTER_FIELD_IP_DSTADDR:
filter0[i].protocol = WINDIVERT_FILTER_PROTOCOL_IP;
break;
case WINDIVERT_FILTER_FIELD_IPV6_TRAFFICCLASS:
case WINDIVERT_FILTER_FIELD_IPV6_FLOWLABEL:
case WINDIVERT_FILTER_FIELD_IPV6_LENGTH:
case WINDIVERT_FILTER_FIELD_IPV6_NEXTHDR:
case WINDIVERT_FILTER_FIELD_IPV6_HOPLIMIT:
case WINDIVERT_FILTER_FIELD_IPV6_SRCADDR:
case WINDIVERT_FILTER_FIELD_IPV6_DSTADDR:
filter0[i].protocol = WINDIVERT_FILTER_PROTOCOL_IPV6;
break;
case WINDIVERT_FILTER_FIELD_ICMP_TYPE:
case WINDIVERT_FILTER_FIELD_ICMP_CODE:
case WINDIVERT_FILTER_FIELD_ICMP_CHECKSUM:
case WINDIVERT_FILTER_FIELD_ICMP_BODY:
filter0[i].protocol = WINDIVERT_FILTER_PROTOCOL_ICMP;
break;
case WINDIVERT_FILTER_FIELD_ICMPV6_TYPE:
case WINDIVERT_FILTER_FIELD_ICMPV6_CODE:
case WINDIVERT_FILTER_FIELD_ICMPV6_CHECKSUM:
case WINDIVERT_FILTER_FIELD_ICMPV6_BODY:
filter0[i].protocol = WINDIVERT_FILTER_PROTOCOL_ICMPV6;
break;
case WINDIVERT_FILTER_FIELD_TCP_SRCPORT:
case WINDIVERT_FILTER_FIELD_TCP_DSTPORT:
case WINDIVERT_FILTER_FIELD_TCP_SEQNUM:
case WINDIVERT_FILTER_FIELD_TCP_ACKNUM:
case WINDIVERT_FILTER_FIELD_TCP_HDRLENGTH:
case WINDIVERT_FILTER_FIELD_TCP_URG:
case WINDIVERT_FILTER_FIELD_TCP_ACK:
case WINDIVERT_FILTER_FIELD_TCP_PSH:
case WINDIVERT_FILTER_FIELD_TCP_RST:
case WINDIVERT_FILTER_FIELD_TCP_SYN:
case WINDIVERT_FILTER_FIELD_TCP_FIN:
case WINDIVERT_FILTER_FIELD_TCP_WINDOW:
case WINDIVERT_FILTER_FIELD_TCP_CHECKSUM:
case WINDIVERT_FILTER_FIELD_TCP_URGPTR:
case WINDIVERT_FILTER_FIELD_TCP_PAYLOADLENGTH:
filter0[i].protocol = WINDIVERT_FILTER_PROTOCOL_TCP;
break;
case WINDIVERT_FILTER_FIELD_UDP_SRCPORT:
case WINDIVERT_FILTER_FIELD_UDP_DSTPORT:
case WINDIVERT_FILTER_FIELD_UDP_LENGTH:
case WINDIVERT_FILTER_FIELD_UDP_CHECKSUM:
case WINDIVERT_FILTER_FIELD_UDP_PAYLOADLENGTH:
filter0[i].protocol = WINDIVERT_FILTER_PROTOCOL_UDP;
break;
default:
goto windivert_filter_compile_exit;
}
}
result = (filter_t)windivert_malloc(i*sizeof(struct filter_s), FALSE);
if (result != NULL)
{
RtlMoveMemory(result, filter0, i*sizeof(struct filter_s));
}
windivert_filter_compile_exit:
windivert_free(filter0);
return result;
}