diff options
Diffstat (limited to 'tap-win32/tapdrvr.c')
| -rwxr-xr-x | tap-win32/tapdrvr.c | 331 |
1 files changed, 299 insertions, 32 deletions
diff --git a/tap-win32/tapdrvr.c b/tap-win32/tapdrvr.c index 7eecca7..0997bd5 100755 --- a/tap-win32/tapdrvr.c +++ b/tap-win32/tapdrvr.c @@ -35,7 +35,8 @@ // By default we operate as a "tap" virtual ethernet // 802.3 interface, but we can emulate a "tun" // interface (point-to-point IPv4) through the -// TAP_IOCTL_CONFIG_POINT_TO_POINT ioctl. +// TAP_IOCTL_CONFIG_POINT_TO_POINT or +// TAP_IOCTL_CONFIG_TUN ioctl. //====================================================== #define NDIS_MINIPORT_DRIVER @@ -46,11 +47,27 @@ #define NTSTRSAFE_LIB // Debug info output -#define ALSO_DBGPRINT 1 -#define DEBUGP_AT_DISPATCH 0 +#define ALSO_DBGPRINT 1 +#define DEBUGP_AT_DISPATCH 0 + +//======================================================== +// Check for truncated IPv4 packets, log errors if found. +//======================================================== +#define PACKET_TRUNCATION_CHECK 1 // JYFIXME + +//======================================================== +// EXPERIMENTAL -- Configure TAP device object to be +// accessible from non-administrative accounts, based +// on an advanced properties setting. +// +// Duplicates the functionality of OpenVPN's +// --allow-nonadmin directive. +//======================================================== +#define ENABLE_NONADMIN 1 // JYFIXME #include <ndis.h> #include <ntstrsafe.h> +#include <ntddk.h> #include "lock.h" #include "constants.h" @@ -274,6 +291,10 @@ NDIS_STATUS AdapterCreate UINT l_Index; NDIS_STATUS status; +#if ENABLE_NONADMIN + BOOLEAN enable_non_admin = FALSE; +#endif + //==================================== // Make sure adapter type is supported //==================================== @@ -410,6 +431,25 @@ NDIS_STATUS AdapterCreate } } +#if ENABLE_NONADMIN + /* Read AllowNonAdmin setting from registry */ + { + NDIS_STRING key = NDIS_STRING_CONST("AllowNonAdmin"); + NdisReadConfiguration (&status, &parm, configHandle, + &key, NdisParameterInteger); + if (status == NDIS_STATUS_SUCCESS) + { + if (parm->ParameterType == NdisParameterInteger) + { + if (parm->ParameterData.IntegerData) + { + enable_non_admin = TRUE; + } + } + } + } +#endif + /* Read optional MAC setting from registry */ { NDIS_STRING key = NDIS_STRING_CONST("MAC"); @@ -479,6 +519,11 @@ NDIS_STATUS AdapterCreate l_Adapter->m_InterfaceIsRunning = TRUE; +#if ENABLE_NONADMIN + if (enable_non_admin) + AllowNonAdmin (&l_Adapter->m_Extension); +#endif + return NDIS_STATUS_SUCCESS; } @@ -1011,7 +1056,7 @@ NDIS_STATUS AdapterQuery break; case OID_GEN_LINK_SPEED: - l_Query.m_Long = 100000; + l_Query.m_Long = 100000; // rate / 100 bps break; case OID_802_3_PERMANENT_ADDRESS: @@ -1348,19 +1393,40 @@ AdapterTransmit (IN NDIS_HANDLE p_AdapterContext, __try { - for (l_Index = 0; l_NDIS_Buffer && l_Index < l_PacketLength; - l_Index += l_BufferLength) + l_Index = 0; + while (l_NDIS_Buffer && l_Index < l_PacketLength) { + ULONG newlen; NdisQueryBuffer (l_NDIS_Buffer, (PVOID *) & l_Buffer, &l_BufferLength); + newlen = l_Index + l_BufferLength; + if (newlen > l_PacketLength) + { + NOTE_ERROR (); + goto no_queue; /* overflow */ + } NdisMoveMemory (l_PacketBuffer->m_Data + l_Index, l_Buffer, l_BufferLength); + l_Index = newlen; NdisGetNextBuffer (l_NDIS_Buffer, &l_NDIS_Buffer); } + if (l_Index != l_PacketLength) + { + NOTE_ERROR (); + goto no_queue; /* underflow */ + } DUMP_PACKET ("AdapterTransmit", l_PacketBuffer->m_Data, l_PacketLength); //===================================================== + // If IPv4 packet, check whether or not packet + // was truncated. + //===================================================== +#if PACKET_TRUNCATION_CHECK + IPv4PacketSizeVerify (l_PacketBuffer->m_Data, l_PacketLength, FALSE, "TX", &l_Adapter->m_TxTrunc); +#endif + + //===================================================== // Are we running in DHCP server masquerade mode? // // If so, catch both DHCP requests and ARP queries @@ -1381,6 +1447,7 @@ AdapterTransmit (IN NDIS_HANDLE p_AdapterContext, (PARP_PACKET) l_PacketBuffer->m_Data, l_Adapter->m_dhcp_addr, l_Adapter->m_dhcp_server_ip, + ~0, l_Adapter->m_dhcp_server_mac)) goto no_queue; } @@ -1417,7 +1484,7 @@ AdapterTransmit (IN NDIS_HANDLE p_AdapterContext, // In Point-To-Point mode, check to see whether // packet is ARP or IPv4 (if neither, then drop). //=============================================== - if (l_Adapter->m_PointToPoint) + if (l_Adapter->m_tun) { ETH_HEADER *e; @@ -1438,7 +1505,8 @@ AdapterTransmit (IN NDIS_HANDLE p_AdapterContext, ProcessARP (l_Adapter, (PARP_PACKET) l_PacketBuffer->m_Data, l_Adapter->m_localIP, - l_Adapter->m_remoteIP, + l_Adapter->m_remoteNetwork, + l_Adapter->m_remoteNetmask, l_Adapter->m_TapToUser.dest); default: @@ -1458,7 +1526,7 @@ AdapterTransmit (IN NDIS_HANDLE p_AdapterContext, goto no_queue; // Packet looks like IPv4, queue it. - l_PacketBuffer->m_SizeFlags |= TP_POINT_TO_POINT; + l_PacketBuffer->m_SizeFlags |= TP_TUN; } } @@ -1669,15 +1737,25 @@ TapDeviceHook (IN PDEVICE_OBJECT p_DeviceObject, IN PIRP p_IRP) NULL, NULL, STRSAFE_FILL_BEHIND_NULL | STRSAFE_IGNORE_NULLS, +#if PACKET_TRUNCATION_CHECK + "State=%s Err=[%s/%d] #O=%d Tx=[%d,%d,%d] Rx=[%d,%d,%d] IrpQ=[%d,%d,%d] PktQ=[%d,%d,%d]", +#else "State=%s Err=[%s/%d] #O=%d Tx=[%d,%d] Rx=[%d,%d] IrpQ=[%d,%d,%d] PktQ=[%d,%d,%d]", +#endif state, g_LastErrorFilename, g_LastErrorLineNumber, (int)l_Adapter->m_Extension.m_NumTapOpens, (int)l_Adapter->m_Tx, (int)l_Adapter->m_TxErr, +#if PACKET_TRUNCATION_CHECK + (int)l_Adapter->m_TxTrunc, +#endif (int)l_Adapter->m_Rx, (int)l_Adapter->m_RxErr, +#if PACKET_TRUNCATION_CHECK + (int)l_Adapter->m_RxTrunc, +#endif (int)l_Adapter->m_Extension.m_IrpQueue->size, (int)l_Adapter->m_Extension.m_IrpQueue->max_size, (int)IRP_QUEUE_SIZE, @@ -1708,21 +1786,65 @@ TapDeviceHook (IN PDEVICE_OBJECT p_DeviceObject, IN PIRP p_IRP) } #endif - case TAP_IOCTL_CONFIG_POINT_TO_POINT: + case TAP_IOCTL_CONFIG_TUN: + { + if (l_IrpSp->Parameters.DeviceIoControl.InputBufferLength >= + (sizeof (IPADDR) * 3)) + { + MACADDR dest; + + l_Adapter->m_tun = FALSE; + + GenerateRelatedMAC (dest, l_Adapter->m_MAC, 1); + + l_Adapter->m_localIP = ((IPADDR*) (p_IRP->AssociatedIrp.SystemBuffer))[0]; + l_Adapter->m_remoteNetwork = ((IPADDR*) (p_IRP->AssociatedIrp.SystemBuffer))[1]; + l_Adapter->m_remoteNetmask = ((IPADDR*) (p_IRP->AssociatedIrp.SystemBuffer))[2]; + + // sanity check on network/netmask + if ((l_Adapter->m_remoteNetwork & l_Adapter->m_remoteNetmask) != l_Adapter->m_remoteNetwork) + { + NOTE_ERROR (); + p_IRP->IoStatus.Status = l_Status = STATUS_INVALID_PARAMETER; + break; + } + + COPY_MAC (l_Adapter->m_TapToUser.src, l_Adapter->m_MAC); + COPY_MAC (l_Adapter->m_TapToUser.dest, dest); + COPY_MAC (l_Adapter->m_UserToTap.src, dest); + COPY_MAC (l_Adapter->m_UserToTap.dest, l_Adapter->m_MAC); + + l_Adapter->m_TapToUser.proto = l_Adapter->m_UserToTap.proto = htons (ETH_P_IP); + + l_Adapter->m_tun = TRUE; + + CheckIfDhcpAndTunMode (l_Adapter); + + p_IRP->IoStatus.Information = 1; // Simple boolean value + } + else + { + NOTE_ERROR (); + p_IRP->IoStatus.Status = l_Status = STATUS_INVALID_PARAMETER; + } + + break; + } + + case TAP_IOCTL_CONFIG_POINT_TO_POINT: // Obsoleted by TAP_IOCTL_CONFIG_TUN { if (l_IrpSp->Parameters.DeviceIoControl.InputBufferLength >= (sizeof (IPADDR) * 2)) { MACADDR dest; - l_Adapter->m_PointToPoint = FALSE; + l_Adapter->m_tun = FALSE; GenerateRelatedMAC (dest, l_Adapter->m_MAC, 1); - l_Adapter->m_localIP = - ((IPADDR*) (p_IRP->AssociatedIrp.SystemBuffer))[0]; - l_Adapter->m_remoteIP = - ((IPADDR*) (p_IRP->AssociatedIrp.SystemBuffer))[1]; + l_Adapter->m_localIP = ((IPADDR*) (p_IRP->AssociatedIrp.SystemBuffer))[0]; + l_Adapter->m_remoteNetwork = ((IPADDR*) (p_IRP->AssociatedIrp.SystemBuffer))[1]; + l_Adapter->m_remoteNetmask = ~0; COPY_MAC (l_Adapter->m_TapToUser.src, l_Adapter->m_MAC); COPY_MAC (l_Adapter->m_TapToUser.dest, dest); @@ -1731,9 +1853,9 @@ TapDeviceHook (IN PDEVICE_OBJECT p_DeviceObject, IN PIRP p_IRP) l_Adapter->m_TapToUser.proto = l_Adapter->m_UserToTap.proto = htons (ETH_P_IP); - l_Adapter->m_PointToPoint = TRUE; + l_Adapter->m_tun = TRUE; - CheckIfDhcpAndPointToPointMode (l_Adapter); + CheckIfDhcpAndTunMode (l_Adapter); p_IRP->IoStatus.Information = 1; // Simple boolean value } @@ -1791,7 +1913,7 @@ TapDeviceHook (IN PDEVICE_OBJECT p_DeviceObject, IN PIRP p_IRP) l_Adapter->m_dhcp_enabled = TRUE; l_Adapter->m_dhcp_server_arp = TRUE; - CheckIfDhcpAndPointToPointMode (l_Adapter); + CheckIfDhcpAndTunMode (l_Adapter); p_IRP->IoStatus.Information = 1; // Simple boolean value } @@ -1979,7 +2101,7 @@ TapDeviceHook (IN PDEVICE_OBJECT p_DeviceObject, IN PIRP p_IRP) p_IRP->IoStatus.Status = l_Status = STATUS_UNSUCCESSFUL; p_IRP->IoStatus.Information = 0; } - else if (!l_Adapter->m_PointToPoint && ((l_IrpSp->Parameters.Write.Length) >= ETHERNET_HEADER_SIZE)) + else if (!l_Adapter->m_tun && ((l_IrpSp->Parameters.Write.Length) >= ETHERNET_HEADER_SIZE)) { __try { @@ -1989,6 +2111,18 @@ TapDeviceHook (IN PDEVICE_OBJECT p_DeviceObject, IN PIRP p_IRP) (unsigned char *) p_IRP->AssociatedIrp.SystemBuffer, l_IrpSp->Parameters.Write.Length); + //===================================================== + // If IPv4 packet, check whether or not packet + // was truncated. + //===================================================== +#if PACKET_TRUNCATION_CHECK + IPv4PacketSizeVerify ((unsigned char *) p_IRP->AssociatedIrp.SystemBuffer, + l_IrpSp->Parameters.Write.Length, + FALSE, + "RX", + &l_Adapter->m_RxTrunc); +#endif + NdisMEthIndicateReceive (l_Adapter->m_MiniportAdapterHandle, (NDIS_HANDLE) l_Adapter, @@ -2011,7 +2145,7 @@ TapDeviceHook (IN PDEVICE_OBJECT p_DeviceObject, IN PIRP p_IRP) p_IRP->IoStatus.Information = 0; } } - else if (l_Adapter->m_PointToPoint && ((l_IrpSp->Parameters.Write.Length) >= IP_HEADER_SIZE)) + else if (l_Adapter->m_tun && ((l_IrpSp->Parameters.Write.Length) >= IP_HEADER_SIZE)) { __try { @@ -2022,6 +2156,18 @@ TapDeviceHook (IN PDEVICE_OBJECT p_DeviceObject, IN PIRP p_IRP) (unsigned char *) p_IRP->AssociatedIrp.SystemBuffer, l_IrpSp->Parameters.Write.Length); + //===================================================== + // If IPv4 packet, check whether or not packet + // was truncated. + //===================================================== +#if PACKET_TRUNCATION_CHECK + IPv4PacketSizeVerify ((unsigned char *) p_IRP->AssociatedIrp.SystemBuffer, + l_IrpSp->Parameters.Write.Length, + TRUE, + "RX", + &l_Adapter->m_RxTrunc); +#endif + NdisMEthIndicateReceive (l_Adapter->m_MiniportAdapterHandle, (NDIS_HANDLE) l_Adapter, @@ -2197,7 +2343,7 @@ CompleteIRP (IN PIRP p_IRP, // component. //------------------------------------------- - if (p_PacketBuffer->m_SizeFlags & TP_POINT_TO_POINT) + if (p_PacketBuffer->m_SizeFlags & TP_TUN) { offset = ETHERNET_HEADER_SIZE; len = (int) (p_PacketBuffer->m_SizeFlags & TP_SIZE_MASK) - ETHERNET_HEADER_SIZE; @@ -2379,16 +2525,16 @@ SetMediaStatus (TapAdapterPointer p_Adapter, BOOLEAN state) //====================================================== -// If DHCP mode is used together with Point-to-point -// mode, consider the fact that the P2P remote endpoint -// might be equal to the DHCP masq server address. +// If DHCP mode is used together with tun +// mode, consider the fact that the P2P remote subnet +// might enclose the DHCP masq server address. //====================================================== VOID -CheckIfDhcpAndPointToPointMode (TapAdapterPointer p_Adapter) +CheckIfDhcpAndTunMode (TapAdapterPointer p_Adapter) { - if (p_Adapter->m_PointToPoint && p_Adapter->m_dhcp_enabled) + if (p_Adapter->m_tun && p_Adapter->m_dhcp_enabled) { - if (p_Adapter->m_dhcp_server_ip == p_Adapter->m_remoteIP) + if ((p_Adapter->m_dhcp_server_ip & p_Adapter->m_remoteNetmask) == p_Adapter->m_remoteNetwork) { COPY_MAC (p_Adapter->m_dhcp_server_mac, p_Adapter->m_TapToUser.dest); p_Adapter->m_dhcp_server_arp = FALSE; @@ -2404,7 +2550,8 @@ BOOLEAN ProcessARP (TapAdapterPointer p_Adapter, const PARP_PACKET src, const IPADDR adapter_ip, - const IPADDR ip, + const IPADDR ip_network, + const IPADDR ip_netmask, const MACADDR mac) { //----------------------------------------------- @@ -2420,7 +2567,8 @@ ProcessARP (TapAdapterPointer p_Adapter, && src->m_PROTO_AddressType == htons (ETH_P_IP) && src->m_PROTO_AddressSize == sizeof (IPADDR) && src->m_ARP_IP_Source == adapter_ip - && src->m_ARP_IP_Destination == ip) + && (src->m_ARP_IP_Destination & ip_netmask) == ip_network + && src->m_ARP_IP_Destination != adapter_ip) { ARP_PACKET *arp = (ARP_PACKET *) MemAlloc (sizeof (ARP_PACKET), TRUE); if (arp) @@ -2442,7 +2590,7 @@ ProcessARP (TapAdapterPointer p_Adapter, COPY_MAC (arp->m_MAC_Destination, p_Adapter->m_MAC); COPY_MAC (arp->m_ARP_MAC_Source, mac); COPY_MAC (arp->m_ARP_MAC_Destination, p_Adapter->m_MAC); - arp->m_ARP_IP_Source = ip; + arp->m_ARP_IP_Source = src->m_ARP_IP_Destination; arp->m_ARP_IP_Destination = adapter_ip; DUMP_PACKET ("ProcessARP", @@ -2508,9 +2656,10 @@ InjectPacket (TapAdapterPointer p_Adapter, VOID ResetTapAdapterState (TapAdapterPointer p_Adapter) { // Point-To-Point - p_Adapter->m_PointToPoint = FALSE; + p_Adapter->m_tun = FALSE; p_Adapter->m_localIP = 0; - p_Adapter->m_remoteIP = 0; + p_Adapter->m_remoteNetwork = 0; + p_Adapter->m_remoteNetmask = 0; NdisZeroMemory (&p_Adapter->m_TapToUser, sizeof (p_Adapter->m_TapToUser)); NdisZeroMemory (&p_Adapter->m_UserToTap, sizeof (p_Adapter->m_UserToTap)); @@ -2526,6 +2675,124 @@ VOID ResetTapAdapterState (TapAdapterPointer p_Adapter) p_Adapter->m_dhcp_bad_requests = 0; NdisZeroMemory (p_Adapter->m_dhcp_server_mac, sizeof (MACADDR)); } + +#if ENABLE_NONADMIN + +//=================================================================== +// Set TAP device handle to be accessible without admin privileges. +//=================================================================== +VOID AllowNonAdmin (TapExtensionPointer p_Extension) +{ + NTSTATUS stat; + SECURITY_DESCRIPTOR sd; + OBJECT_ATTRIBUTES oa; + IO_STATUS_BLOCK isb; + HANDLE hand = NULL; + + NdisZeroMemory (&sd, sizeof (sd)); + NdisZeroMemory (&oa, sizeof (oa)); + NdisZeroMemory (&isb, sizeof (isb)); + + if (!p_Extension->m_CreatedUnicodeLinkName) + { + DEBUGP (("[TAP] AllowNonAdmin: UnicodeLinkName is uninitialized\n")); + NOTE_ERROR (); + return; + } + + stat = RtlCreateSecurityDescriptor (&sd, SECURITY_DESCRIPTOR_REVISION); + if (stat != STATUS_SUCCESS) + { + DEBUGP (("[TAP] AllowNonAdmin: RtlCreateSecurityDescriptor failed\n")); + NOTE_ERROR (); + return; + } + + InitializeObjectAttributes ( + &oa, + &p_Extension->m_UnicodeLinkName, + OBJ_KERNEL_HANDLE, + NULL, + NULL + ); + + stat = ZwOpenFile ( + &hand, + WRITE_DAC, + &oa, + &isb, + 0, + 0 + ); + if (stat != STATUS_SUCCESS) + { + DEBUGP (("[TAP] AllowNonAdmin: ZwOpenFile failed, status=0x%08x\n", (unsigned int)stat)); + NOTE_ERROR (); + return; + } + + stat = ZwSetSecurityObject (hand, DACL_SECURITY_INFORMATION, &sd); + if (stat != STATUS_SUCCESS) + { + DEBUGP (("[TAP] AllowNonAdmin: ZwSetSecurityObject failed\n")); + NOTE_ERROR (); + return; + } + + stat = ZwClose (hand); + if (stat != STATUS_SUCCESS) + { + DEBUGP (("[TAP] AllowNonAdmin: ZwClose failed\n")); + NOTE_ERROR (); + return; + } + + DEBUGP (("[TAP] AllowNonAdmin: SUCCEEDED\n")); +} + +#endif + +#if PACKET_TRUNCATION_CHECK + +VOID +IPv4PacketSizeVerify (const UCHAR *data, ULONG length, BOOLEAN tun, const char *prefix, LONG *counter) +{ + const IPHDR *ip; + int len = length; + + if (tun) + { + ip = (IPHDR *) data; + } + else + { + if (length >= sizeof (ETH_HEADER)) + { + const ETH_HEADER *eth = (ETH_HEADER *) data; + + if (eth->proto != htons (ETH_P_IP)) + return; + + ip = (IPHDR *) (data + sizeof (ETH_HEADER)); + len -= sizeof (ETH_HEADER); + } + else + return; + } + + if (len >= sizeof (IPHDR)) + { + const int totlen = ntohs (ip->tot_len); + + DEBUGP (("[TAP] IPv4PacketSizeVerify %s len=%d totlen=%d\n", prefix, len, totlen)); + + if (len != totlen) + ++(*counter); + } +} + +#endif + //====================================================================== // End of Source //====================================================================== |