mirror of
https://github.com/reactos/reactos.git
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1481 lines
50 KiB
C
1481 lines
50 KiB
C
/*
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* PROJECT: ReactOS Winlogon
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* LICENSE: GPL-2.0-or-later (https://spdx.org/licenses/GPL-2.0-or-later)
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* PURPOSE: Security utility infrastructure implementation of Winlogon
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* COPYRIGHT: Copyright 2022 George Bișoc <george.bisoc@reactos.org>
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*/
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/* INCLUDES *****************************************************************/
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#include "winlogon.h"
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/* DEFINES ******************************************************************/
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#define DESKTOP_ALL (DESKTOP_READOBJECTS | DESKTOP_CREATEWINDOW | \
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DESKTOP_CREATEMENU | DESKTOP_HOOKCONTROL | DESKTOP_JOURNALRECORD | \
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DESKTOP_JOURNALPLAYBACK | DESKTOP_ENUMERATE | DESKTOP_WRITEOBJECTS | \
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DESKTOP_SWITCHDESKTOP | STANDARD_RIGHTS_REQUIRED)
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#define DESKTOP_ADMINS_LIMITED (DESKTOP_WRITEOBJECTS | DESKTOP_READOBJECTS | \
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DESKTOP_CREATEWINDOW | DESKTOP_CREATEMENU | DESKTOP_ENUMERATE)
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#define DESKTOP_INTERACTIVE_LIMITED (STANDARD_RIGHTS_READ | DESKTOP_ENUMERATE | \
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DESKTOP_READOBJECTS | DESKTOP_CREATEWINDOW)
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#define DESKTOP_WINLOGON_ADMINS_LIMITED (STANDARD_RIGHTS_REQUIRED | DESKTOP_ENUMERATE)
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#define WINSTA_ALL (WINSTA_ENUMDESKTOPS | WINSTA_READATTRIBUTES | \
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WINSTA_ACCESSCLIPBOARD | WINSTA_CREATEDESKTOP | \
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WINSTA_WRITEATTRIBUTES | WINSTA_ACCESSGLOBALATOMS | \
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WINSTA_EXITWINDOWS | WINSTA_ENUMERATE | WINSTA_READSCREEN | \
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STANDARD_RIGHTS_REQUIRED)
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#define WINSTA_ADMINS_LIMITED (WINSTA_READATTRIBUTES | WINSTA_ENUMERATE)
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#define GENERIC_ACCESS (GENERIC_READ | GENERIC_WRITE | \
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GENERIC_EXECUTE | GENERIC_ALL)
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/* GLOBALS ******************************************************************/
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static SID_IDENTIFIER_AUTHORITY NtAuthority = {SECURITY_NT_AUTHORITY};
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/* FUNCTIONS ****************************************************************/
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/**
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* @brief
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* Converts an absolute security descriptor to a self-relative
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* format.
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*
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* @param[in] AbsoluteSd
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* A pointer to an absolute security descriptor to be
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* converted.
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*
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* @return
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* Returns a pointer to a converted security descriptor in
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* self-relative format. If the function fails, NULL is returned
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* otherwise.
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*
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* @remarks
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* The function allocates the security descriptor buffer in memory
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* heap, the caller is entirely responsible for freeing such buffer
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* from when it's no longer needed.
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*/
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PSECURITY_DESCRIPTOR
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ConvertToSelfRelative(
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_In_ PSECURITY_DESCRIPTOR AbsoluteSd)
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{
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PSECURITY_DESCRIPTOR RelativeSd;
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DWORD DescriptorLength = 0;
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/* Determine the size for our buffer to allocate */
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if (!MakeSelfRelativeSD(AbsoluteSd, NULL, &DescriptorLength) && GetLastError() != ERROR_INSUFFICIENT_BUFFER)
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{
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ERR("ConvertToSelfRelative(): Unexpected error code (error code %lu -- must be ERROR_INSUFFICIENT_BUFFER)\n", GetLastError());
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return NULL;
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}
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/* Allocate the buffer now */
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RelativeSd = RtlAllocateHeap(RtlGetProcessHeap(),
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HEAP_ZERO_MEMORY,
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DescriptorLength);
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if (RelativeSd == NULL)
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{
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ERR("ConvertToSelfRelative(): Failed to allocate buffer for relative SD!\n");
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return NULL;
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}
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/* Convert the security descriptor now */
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if (!MakeSelfRelativeSD(AbsoluteSd, RelativeSd, &DescriptorLength))
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{
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ERR("ConvertToSelfRelative(): Failed to convert the security descriptor to a self relative format (error code %lu)\n", GetLastError());
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RtlFreeHeap(RtlGetProcessHeap(), 0, RelativeSd);
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return NULL;
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}
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return RelativeSd;
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}
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/**
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* @brief
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* Creates a security descriptor for the default
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* window station upon its creation.
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*
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* @param[out] WinstaSd
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* A pointer to a created security descriptor for
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* the window station.
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*
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* @return
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* Returns TRUE if the function has successfully
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* created the security descriptor, FALSE otherwise.
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*/
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BOOL
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CreateWinstaSecurity(
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_Out_ PSECURITY_DESCRIPTOR *WinstaSd)
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{
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BOOL Success = FALSE;
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SECURITY_DESCRIPTOR AbsoluteSd;
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PSECURITY_DESCRIPTOR RelativeSd = NULL;
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PSID WinlogonSid = NULL, AdminsSid = NULL, NetworkServiceSid = NULL; /* NetworkServiceSid is a HACK, see the comment below for information */
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DWORD DaclSize;
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PACL Dacl;
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/* Create the Winlogon SID */
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if (!AllocateAndInitializeSid(&NtAuthority,
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1,
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SECURITY_LOCAL_SYSTEM_RID,
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0, 0, 0, 0, 0, 0, 0,
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&WinlogonSid))
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{
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ERR("CreateWinstaSecurity(): Failed to create the Winlogon SID (error code %lu)\n", GetLastError());
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return FALSE;
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}
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/* Create the admins SID */
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if (!AllocateAndInitializeSid(&NtAuthority,
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2,
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SECURITY_BUILTIN_DOMAIN_RID,
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DOMAIN_ALIAS_RID_ADMINS,
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0, 0, 0, 0, 0, 0,
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&AdminsSid))
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{
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ERR("CreateWinstaSecurity(): Failed to create the admins SID (error code %lu)\n", GetLastError());
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goto Quit;
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}
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/* HACK: Create the network service SID */
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if (!AllocateAndInitializeSid(&NtAuthority,
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1,
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SECURITY_NETWORK_SERVICE_RID,
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0, 0, 0, 0, 0, 0, 0,
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&NetworkServiceSid))
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{
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ERR("CreateWinstaSecurity(): Failed to create the network service SID (error code %lu)\n", GetLastError());
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goto Quit;
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}
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/*
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* Build up the DACL size. This includes a number
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* of four ACEs of two different SIDs. The first two
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* ACEs give both window station and generic access
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* to Winlogon, the last two give limited window station
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* and desktop access to admins.
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*
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* ===================== !!!MUST READ!!! =====================
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*
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* HACK -- Include in the DACL two more ACEs for network
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* service SID. Network services will be granted full
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* access to the default window station. Whilst technically
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* services that are either network or local ones are part
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* and act on behalf of the system, what we are doing here
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* is a hack because of two reasons:
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*
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* 1) Winlogon does not allow default window station (Winsta0)
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* access to network services on Windows. As a matter of fact,
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* network services must access their own service window station
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* (aka Service-0x0-3e4$) which never gets created. Why it never
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* gets created is explained on the second point.
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*
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* 2) Our LSASS terribly lacks in code that handles special logon
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* service types, NetworkService and LocalService. For this reason
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* whenever an access token is created for a network service process
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* for example, its authentication ID (aka LogonId represented as a LUID)
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* is a uniquely generated ID by LSASS for this process. This is wrong
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* on so many levels, partly because a network service is not a regular
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* service and network services have their own special authentication logon
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* ID (with its respective LUID as {0x3e4, 0x0}). On top of that, a network
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* service process must have an impersonation token but for whatever reason
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* we are creating a primary access token instead.
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*
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* FOR ANYONE WHO'S INTERESTED ON FIXING THIS, DO NOT FORGET TO REMOVE THIS
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* HACK!!!
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*
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* =========================== !!!END!!! ================================
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*/
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DaclSize = sizeof(ACL) +
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sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD) + GetLengthSid(WinlogonSid) +
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sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD) + GetLengthSid(WinlogonSid) +
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sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD) + GetLengthSid(AdminsSid) +
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sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD) + GetLengthSid(AdminsSid) +
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sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD) + GetLengthSid(NetworkServiceSid) +
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sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD) + GetLengthSid(NetworkServiceSid);
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/* Allocate the DACL now */
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Dacl = RtlAllocateHeap(RtlGetProcessHeap(),
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HEAP_ZERO_MEMORY,
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DaclSize);
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if (Dacl == NULL)
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{
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ERR("CreateWinstaSecurity(): Failed to allocate memory buffer for DACL!\n");
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goto Quit;
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}
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/* Initialize it */
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if (!InitializeAcl(Dacl, DaclSize, ACL_REVISION))
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{
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ERR("CreateWinstaSecurity(): Failed to initialize DACL (error code %lu)\n", GetLastError());
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goto Quit;
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}
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/* First ACE -- give full winsta access to Winlogon */
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if (!AddAccessAllowedAceEx(Dacl,
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ACL_REVISION,
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NO_PROPAGATE_INHERIT_ACE,
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WINSTA_ALL,
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WinlogonSid))
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{
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ERR("CreateWinstaSecurity(): Failed to set ACE for Winlogon (error code %lu)\n", GetLastError());
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goto Quit;
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}
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/* Second ACE -- give full generic access to Winlogon */
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if (!AddAccessAllowedAceEx(Dacl,
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ACL_REVISION,
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INHERIT_ONLY_ACE | OBJECT_INHERIT_ACE | CONTAINER_INHERIT_ACE,
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GENERIC_ACCESS,
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WinlogonSid))
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{
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ERR("CreateWinstaSecurity(): Failed to set ACE for Winlogon (error code %lu)\n", GetLastError());
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goto Quit;
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}
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/* Third ACE -- give limited winsta access to admins */
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if (!AddAccessAllowedAceEx(Dacl,
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ACL_REVISION,
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NO_PROPAGATE_INHERIT_ACE,
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WINSTA_ADMINS_LIMITED,
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AdminsSid))
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{
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ERR("CreateWinstaSecurity(): Failed to set ACE for admins (error code %lu)\n", GetLastError());
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goto Quit;
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}
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/* Fourth ACE -- give limited desktop access to admins */
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if (!AddAccessAllowedAceEx(Dacl,
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ACL_REVISION,
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INHERIT_ONLY_ACE | OBJECT_INHERIT_ACE | CONTAINER_INHERIT_ACE,
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DESKTOP_ADMINS_LIMITED,
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AdminsSid))
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{
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ERR("CreateWinstaSecurity(): Failed to set ACE for admins (error code %lu)\n", GetLastError());
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goto Quit;
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}
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/* HACK: Fifth ACE -- give full access to network services */
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if (!AddAccessAllowedAceEx(Dacl,
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ACL_REVISION,
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NO_PROPAGATE_INHERIT_ACE,
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WINSTA_ALL,
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NetworkServiceSid))
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{
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ERR("CreateWinstaSecurity(): Failed to set ACE for network service (error code %lu)\n", GetLastError());
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goto Quit;
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}
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/* HACK: Sixth ACE -- give full generic access to network services */
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if (!AddAccessAllowedAceEx(Dacl,
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ACL_REVISION,
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INHERIT_ONLY_ACE | OBJECT_INHERIT_ACE | CONTAINER_INHERIT_ACE,
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GENERIC_ACCESS,
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NetworkServiceSid))
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{
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ERR("CreateWinstaSecurity(): Failed to set ACE for network service (error code %lu)\n", GetLastError());
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goto Quit;
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}
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/* Initialize the security descriptor */
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if (!InitializeSecurityDescriptor(&AbsoluteSd, SECURITY_DESCRIPTOR_REVISION))
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{
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ERR("CreateWinstaSecurity(): Failed to initialize absolute security descriptor (error code %lu)\n", GetLastError());
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goto Quit;
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}
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/* Set the DACL to the descriptor */
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if (!SetSecurityDescriptorDacl(&AbsoluteSd, TRUE, Dacl, FALSE))
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{
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ERR("CreateWinstaSecurity(): Failed to set up DACL to absolute security descriptor (error code %lu)\n", GetLastError());
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goto Quit;
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}
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/* Convert it to self-relative format */
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RelativeSd = ConvertToSelfRelative(&AbsoluteSd);
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if (RelativeSd == NULL)
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{
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ERR("CreateWinstaSecurity(): Failed to convert security descriptor to self relative format!\n");
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goto Quit;
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}
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/* Give the descriptor to the caller */
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*WinstaSd = RelativeSd;
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Success = TRUE;
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Quit:
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if (WinlogonSid != NULL)
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{
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FreeSid(WinlogonSid);
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}
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if (AdminsSid != NULL)
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{
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FreeSid(AdminsSid);
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}
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/* HACK */
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if (NetworkServiceSid != NULL)
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{
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FreeSid(NetworkServiceSid);
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}
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/* END HACK */
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if (Dacl != NULL)
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{
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RtlFreeHeap(RtlGetProcessHeap(), 0, Dacl);
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}
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if (Success == FALSE)
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{
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if (RelativeSd != NULL)
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{
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RtlFreeHeap(RtlGetProcessHeap(), 0, RelativeSd);
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}
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}
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return Success;
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}
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/**
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* @brief
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* Creates a security descriptor for the default
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* application desktop upon its creation.
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*
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* @param[out] ApplicationDesktopSd
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* A pointer to a created security descriptor for
|
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* the application desktop.
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*
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* @return
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* Returns TRUE if the function has successfully
|
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* created the security descriptor, FALSE otherwise.
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*/
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BOOL
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CreateApplicationDesktopSecurity(
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_Out_ PSECURITY_DESCRIPTOR *ApplicationDesktopSd)
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|
{
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BOOL Success = FALSE;
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SECURITY_DESCRIPTOR AbsoluteSd;
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PSECURITY_DESCRIPTOR RelativeSd = NULL;
|
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PSID WinlogonSid = NULL, AdminsSid = NULL, NetworkServiceSid = NULL; /* NetworkServiceSid is a HACK, see the comment in CreateWinstaSecurity for information */
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DWORD DaclSize;
|
|
PACL Dacl;
|
|
|
|
/* Create the Winlogon SID */
|
|
if (!AllocateAndInitializeSid(&NtAuthority,
|
|
1,
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|
SECURITY_LOCAL_SYSTEM_RID,
|
|
0, 0, 0, 0, 0, 0, 0,
|
|
&WinlogonSid))
|
|
{
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ERR("CreateApplicationDesktopSecurity(): Failed to create the Winlogon SID (error code %lu)\n", GetLastError());
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return FALSE;
|
|
}
|
|
|
|
/* Create the admins SID */
|
|
if (!AllocateAndInitializeSid(&NtAuthority,
|
|
2,
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|
SECURITY_BUILTIN_DOMAIN_RID,
|
|
DOMAIN_ALIAS_RID_ADMINS,
|
|
0, 0, 0, 0, 0, 0,
|
|
&AdminsSid))
|
|
{
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ERR("CreateApplicationDesktopSecurity(): Failed to create the admins SID (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* HACK: Create the network service SID */
|
|
if (!AllocateAndInitializeSid(&NtAuthority,
|
|
1,
|
|
SECURITY_NETWORK_SERVICE_RID,
|
|
0, 0, 0, 0, 0, 0, 0,
|
|
&NetworkServiceSid))
|
|
{
|
|
ERR("CreateApplicationDesktopSecurity(): Failed to create the network service SID (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/*
|
|
* Build up the DACL size. This includes a number
|
|
* of two ACEs of two different SIDs. The first ACE
|
|
* gives full access to Winlogon, the last one gives
|
|
* limited desktop access to admins.
|
|
*/
|
|
DaclSize = sizeof(ACL) +
|
|
sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD) + GetLengthSid(WinlogonSid) +
|
|
sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD) + GetLengthSid(AdminsSid) +
|
|
sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD) + GetLengthSid(NetworkServiceSid); /* HACK */
|
|
|
|
/* Allocate the DACL now */
|
|
Dacl = RtlAllocateHeap(RtlGetProcessHeap(),
|
|
HEAP_ZERO_MEMORY,
|
|
DaclSize);
|
|
if (Dacl == NULL)
|
|
{
|
|
ERR("CreateApplicationDesktopSecurity(): Failed to allocate memory buffer for DACL!\n");
|
|
goto Quit;
|
|
}
|
|
|
|
/* Initialize it */
|
|
if (!InitializeAcl(Dacl, DaclSize, ACL_REVISION))
|
|
{
|
|
ERR("CreateApplicationDesktopSecurity(): Failed to initialize DACL (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* First ACE -- Give full desktop power to Winlogon */
|
|
if (!AddAccessAllowedAceEx(Dacl,
|
|
ACL_REVISION,
|
|
0,
|
|
DESKTOP_ALL,
|
|
WinlogonSid))
|
|
{
|
|
ERR("CreateApplicationDesktopSecurity(): Failed to set ACE for Winlogon (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Second ACE -- Give limited desktop power to admins */
|
|
if (!AddAccessAllowedAceEx(Dacl,
|
|
ACL_REVISION,
|
|
0,
|
|
DESKTOP_ADMINS_LIMITED,
|
|
AdminsSid))
|
|
{
|
|
ERR("CreateApplicationDesktopSecurity(): Failed to set ACE for admins (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* HACK: Third ACE -- Give full desktop power to network services */
|
|
if (!AddAccessAllowedAceEx(Dacl,
|
|
ACL_REVISION,
|
|
0,
|
|
DESKTOP_ALL,
|
|
NetworkServiceSid))
|
|
{
|
|
ERR("CreateApplicationDesktopSecurity(): Failed to set ACE for network services (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Initialize the security descriptor */
|
|
if (!InitializeSecurityDescriptor(&AbsoluteSd, SECURITY_DESCRIPTOR_REVISION))
|
|
{
|
|
ERR("CreateApplicationDesktopSecurity(): Failed to initialize absolute security descriptor (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Set the DACL to the descriptor */
|
|
if (!SetSecurityDescriptorDacl(&AbsoluteSd, TRUE, Dacl, FALSE))
|
|
{
|
|
ERR("CreateApplicationDesktopSecurity(): Failed to set up DACL to absolute security descriptor (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Conver it to self-relative format */
|
|
RelativeSd = ConvertToSelfRelative(&AbsoluteSd);
|
|
if (RelativeSd == NULL)
|
|
{
|
|
ERR("CreateApplicationDesktopSecurity(): Failed to convert security descriptor to self relative format!\n");
|
|
goto Quit;
|
|
}
|
|
|
|
/* Give the descriptor to the caller */
|
|
*ApplicationDesktopSd = RelativeSd;
|
|
Success = TRUE;
|
|
|
|
Quit:
|
|
if (WinlogonSid != NULL)
|
|
{
|
|
FreeSid(WinlogonSid);
|
|
}
|
|
|
|
if (AdminsSid != NULL)
|
|
{
|
|
FreeSid(AdminsSid);
|
|
}
|
|
|
|
/* HACK */
|
|
if (NetworkServiceSid != NULL)
|
|
{
|
|
FreeSid(NetworkServiceSid);
|
|
}
|
|
/* END HACK */
|
|
|
|
if (Dacl != NULL)
|
|
{
|
|
RtlFreeHeap(RtlGetProcessHeap(), 0, Dacl);
|
|
}
|
|
|
|
if (Success == FALSE)
|
|
{
|
|
if (RelativeSd != NULL)
|
|
{
|
|
RtlFreeHeap(RtlGetProcessHeap(), 0, RelativeSd);
|
|
}
|
|
}
|
|
|
|
return Success;
|
|
}
|
|
|
|
/**
|
|
* @brief
|
|
* Creates a security descriptor for the default
|
|
* Winlogon desktop. This descriptor serves as a
|
|
* security measure for the winlogon desktop so
|
|
* that only Winlogon itself (and admins) can
|
|
* interact with it.
|
|
*
|
|
* @param[out] WinlogonDesktopSd
|
|
* A pointer to a created security descriptor for
|
|
* the Winlogon desktop.
|
|
*
|
|
* @return
|
|
* Returns TRUE if the function has successfully
|
|
* created the security descriptor, FALSE otherwise.
|
|
*/
|
|
BOOL
|
|
CreateWinlogonDesktopSecurity(
|
|
_Out_ PSECURITY_DESCRIPTOR *WinlogonDesktopSd)
|
|
{
|
|
BOOL Success = FALSE;
|
|
SECURITY_DESCRIPTOR AbsoluteSd;
|
|
PSECURITY_DESCRIPTOR RelativeSd = NULL;
|
|
PSID WinlogonSid = NULL, AdminsSid = NULL;
|
|
DWORD DaclSize;
|
|
PACL Dacl;
|
|
|
|
/* Create the Winlogon SID */
|
|
if (!AllocateAndInitializeSid(&NtAuthority,
|
|
1,
|
|
SECURITY_LOCAL_SYSTEM_RID,
|
|
0, 0, 0, 0, 0, 0, 0,
|
|
&WinlogonSid))
|
|
{
|
|
ERR("CreateWinlogonDesktopSecurity(): Failed to create the Winlogon SID (error code %lu)\n", GetLastError());
|
|
return FALSE;
|
|
}
|
|
|
|
/* Create the admins SID */
|
|
if (!AllocateAndInitializeSid(&NtAuthority,
|
|
2,
|
|
SECURITY_BUILTIN_DOMAIN_RID,
|
|
DOMAIN_ALIAS_RID_ADMINS,
|
|
0, 0, 0, 0, 0, 0,
|
|
&AdminsSid))
|
|
{
|
|
ERR("CreateWinlogonDesktopSecurity(): Failed to create the admins SID (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/*
|
|
* Build up the DACL size. This includes a number
|
|
* of two ACEs of two different SIDs. The first ACE
|
|
* gives full access to Winlogon, the last one gives
|
|
* limited desktop access to admins.
|
|
*/
|
|
DaclSize = sizeof(ACL) +
|
|
sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD) + GetLengthSid(WinlogonSid) +
|
|
sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD) + GetLengthSid(AdminsSid);
|
|
|
|
/* Allocate the DACL now */
|
|
Dacl = RtlAllocateHeap(RtlGetProcessHeap(),
|
|
HEAP_ZERO_MEMORY,
|
|
DaclSize);
|
|
if (Dacl == NULL)
|
|
{
|
|
ERR("CreateWinlogonDesktopSecurity(): Failed to allocate memory buffer for DACL!\n");
|
|
goto Quit;
|
|
}
|
|
|
|
/* Initialize it */
|
|
if (!InitializeAcl(Dacl, DaclSize, ACL_REVISION))
|
|
{
|
|
ERR("CreateWinlogonDesktopSecurity(): Failed to initialize DACL (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* First ACE -- Give full desktop access to Winlogon */
|
|
if (!AddAccessAllowedAceEx(Dacl,
|
|
ACL_REVISION,
|
|
0,
|
|
DESKTOP_ALL,
|
|
WinlogonSid))
|
|
{
|
|
ERR("CreateWinlogonDesktopSecurity(): Failed to set ACE for Winlogon (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Second ACE -- Give limited desktop access to admins */
|
|
if (!AddAccessAllowedAceEx(Dacl,
|
|
ACL_REVISION,
|
|
0,
|
|
DESKTOP_WINLOGON_ADMINS_LIMITED,
|
|
AdminsSid))
|
|
{
|
|
ERR("CreateWinlogonDesktopSecurity(): Failed to set ACE for admins (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Initialize the security descriptor */
|
|
if (!InitializeSecurityDescriptor(&AbsoluteSd, SECURITY_DESCRIPTOR_REVISION))
|
|
{
|
|
ERR("CreateWinlogonDesktopSecurity(): Failed to initialize absolute security descriptor (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Set the DACL to the descriptor */
|
|
if (!SetSecurityDescriptorDacl(&AbsoluteSd, TRUE, Dacl, FALSE))
|
|
{
|
|
ERR("CreateWinlogonDesktopSecurity(): Failed to set up DACL to absolute security descriptor (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Conver it to self-relative format */
|
|
RelativeSd = ConvertToSelfRelative(&AbsoluteSd);
|
|
if (RelativeSd == NULL)
|
|
{
|
|
ERR("CreateWinlogonDesktopSecurity(): Failed to convert security descriptor to self relative format!\n");
|
|
goto Quit;
|
|
}
|
|
|
|
/* Give the descriptor to the caller */
|
|
*WinlogonDesktopSd = RelativeSd;
|
|
Success = TRUE;
|
|
|
|
Quit:
|
|
if (WinlogonSid != NULL)
|
|
{
|
|
FreeSid(WinlogonSid);
|
|
}
|
|
|
|
if (AdminsSid != NULL)
|
|
{
|
|
FreeSid(AdminsSid);
|
|
}
|
|
|
|
if (Dacl != NULL)
|
|
{
|
|
RtlFreeHeap(RtlGetProcessHeap(), 0, Dacl);
|
|
}
|
|
|
|
if (Success == FALSE)
|
|
{
|
|
if (RelativeSd != NULL)
|
|
{
|
|
RtlFreeHeap(RtlGetProcessHeap(), 0, RelativeSd);
|
|
}
|
|
}
|
|
|
|
return Success;
|
|
}
|
|
|
|
/**
|
|
* @brief
|
|
* Creates a security descriptor for the screen
|
|
* saver desktop.
|
|
*
|
|
* @param[out] ScreenSaverDesktopSd
|
|
* A pointer to a created security descriptor for
|
|
* the screen-saver desktop.
|
|
*
|
|
* @return
|
|
* Returns TRUE if the function has successfully
|
|
* created the security descriptor, FALSE otherwise.
|
|
*/
|
|
BOOL
|
|
CreateScreenSaverSecurity(
|
|
_Out_ PSECURITY_DESCRIPTOR *ScreenSaverDesktopSd)
|
|
{
|
|
BOOL Success = FALSE;
|
|
SECURITY_DESCRIPTOR AbsoluteSd;
|
|
PSECURITY_DESCRIPTOR RelativeSd = NULL;
|
|
PSID WinlogonSid = NULL, AdminsSid = NULL, InteractiveSid = NULL;
|
|
DWORD DaclSize;
|
|
PACL Dacl;
|
|
|
|
/* Create the Winlogon SID */
|
|
if (!AllocateAndInitializeSid(&NtAuthority,
|
|
1,
|
|
SECURITY_LOCAL_SYSTEM_RID,
|
|
0, 0, 0, 0, 0, 0, 0,
|
|
&WinlogonSid))
|
|
{
|
|
ERR("CreateScreenSaverSecurity(): Failed to create the Winlogon SID (error code %lu)\n", GetLastError());
|
|
return FALSE;
|
|
}
|
|
|
|
/* Create the admins SID */
|
|
if (!AllocateAndInitializeSid(&NtAuthority,
|
|
2,
|
|
SECURITY_BUILTIN_DOMAIN_RID,
|
|
DOMAIN_ALIAS_RID_ADMINS,
|
|
0, 0, 0, 0, 0, 0,
|
|
&AdminsSid))
|
|
{
|
|
ERR("CreateScreenSaverSecurity(): Failed to create the admins SID (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Create the interactive logon SID */
|
|
if (!AllocateAndInitializeSid(&NtAuthority,
|
|
1,
|
|
SECURITY_INTERACTIVE_RID,
|
|
0, 0, 0, 0, 0, 0, 0,
|
|
&InteractiveSid))
|
|
{
|
|
ERR("CreateScreenSaverSecurity(): Failed to create the interactive SID (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/*
|
|
* Build up the DACL size. This includes a number
|
|
* of three ACEs of three different SIDs. The first ACE
|
|
* gives full access to Winlogon, the second one gives
|
|
* limited desktop access to admins and the last one
|
|
* gives full desktop access to users who have logged in
|
|
* interactively.
|
|
*/
|
|
DaclSize = sizeof(ACL) +
|
|
sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD) + GetLengthSid(WinlogonSid) +
|
|
sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD) + GetLengthSid(AdminsSid) +
|
|
sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD) + GetLengthSid(InteractiveSid);
|
|
|
|
/* Allocate the DACL now */
|
|
Dacl = RtlAllocateHeap(RtlGetProcessHeap(),
|
|
HEAP_ZERO_MEMORY,
|
|
DaclSize);
|
|
if (Dacl == NULL)
|
|
{
|
|
ERR("CreateScreenSaverSecurity(): Failed to allocate memory buffer for DACL!\n");
|
|
goto Quit;
|
|
}
|
|
|
|
/* Initialize it */
|
|
if (!InitializeAcl(Dacl, DaclSize, ACL_REVISION))
|
|
{
|
|
ERR("CreateScreenSaverSecurity(): Failed to initialize DACL (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* First ACE -- Give full desktop access to Winlogon */
|
|
if (!AddAccessAllowedAceEx(Dacl,
|
|
ACL_REVISION,
|
|
0,
|
|
DESKTOP_ALL,
|
|
WinlogonSid))
|
|
{
|
|
ERR("CreateScreenSaverSecurity(): Failed to set ACE for Winlogon (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Second ACE -- Give limited desktop access to admins */
|
|
if (!AddAccessAllowedAceEx(Dacl,
|
|
ACL_REVISION,
|
|
NO_PROPAGATE_INHERIT_ACE,
|
|
DESKTOP_ADMINS_LIMITED,
|
|
AdminsSid))
|
|
{
|
|
ERR("CreateScreenSaverSecurity(): Failed to set ACE for admins (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Third ACE -- Give full desktop access to interactive logon users */
|
|
if (!AddAccessAllowedAceEx(Dacl,
|
|
ACL_REVISION,
|
|
NO_PROPAGATE_INHERIT_ACE,
|
|
DESKTOP_INTERACTIVE_LIMITED,
|
|
InteractiveSid))
|
|
{
|
|
ERR("CreateScreenSaverSecurity(): Failed to set ACE for interactive SID (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Initialize the security descriptor */
|
|
if (!InitializeSecurityDescriptor(&AbsoluteSd, SECURITY_DESCRIPTOR_REVISION))
|
|
{
|
|
ERR("CreateScreenSaverSecurity(): Failed to initialize absolute security descriptor (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Set the DACL to the descriptor */
|
|
if (!SetSecurityDescriptorDacl(&AbsoluteSd, TRUE, Dacl, FALSE))
|
|
{
|
|
ERR("CreateScreenSaverSecurity(): Failed to set up DACL to absolute security descriptor (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Conver it to self-relative format */
|
|
RelativeSd = ConvertToSelfRelative(&AbsoluteSd);
|
|
if (RelativeSd == NULL)
|
|
{
|
|
ERR("CreateScreenSaverSecurity(): Failed to convert security descriptor to self relative format!\n");
|
|
goto Quit;
|
|
}
|
|
|
|
/* Give the descriptor to the caller */
|
|
*ScreenSaverDesktopSd = RelativeSd;
|
|
Success = TRUE;
|
|
|
|
Quit:
|
|
if (WinlogonSid != NULL)
|
|
{
|
|
FreeSid(WinlogonSid);
|
|
}
|
|
|
|
if (AdminsSid != NULL)
|
|
{
|
|
FreeSid(AdminsSid);
|
|
}
|
|
|
|
if (InteractiveSid != NULL)
|
|
{
|
|
FreeSid(InteractiveSid);
|
|
}
|
|
|
|
if (Dacl != NULL)
|
|
{
|
|
RtlFreeHeap(RtlGetProcessHeap(), 0, Dacl);
|
|
}
|
|
|
|
if (Success == FALSE)
|
|
{
|
|
if (RelativeSd != NULL)
|
|
{
|
|
RtlFreeHeap(RtlGetProcessHeap(), 0, RelativeSd);
|
|
}
|
|
}
|
|
|
|
return Success;
|
|
}
|
|
|
|
/**
|
|
* @brief
|
|
* Assigns access to the specific logon user to
|
|
* the default window station. Such access is
|
|
* given to the user when it has logged in.
|
|
*
|
|
* @param[in] WinSta
|
|
* A handle to a window station where the
|
|
* user is given access to it.
|
|
*
|
|
* @param[in] LogonSid
|
|
* A pointer to a logon SID that represents
|
|
* the logged in user in question.
|
|
*
|
|
* @return
|
|
* Returns TRUE if the function has successfully
|
|
* assigned access to the user, FALSE otherwise.
|
|
*/
|
|
BOOL
|
|
AllowWinstaAccessToUser(
|
|
_In_ HWINSTA WinSta,
|
|
_In_ PSID LogonSid)
|
|
{
|
|
BOOL Success = FALSE;
|
|
SECURITY_DESCRIPTOR AbsoluteSd;
|
|
PSECURITY_DESCRIPTOR RelativeSd = NULL;
|
|
PSID WinlogonSid = NULL, AdminsSid = NULL, InteractiveSid = NULL, NetworkServiceSid = NULL; /* NetworkServiceSid is a HACK, see the comment in CreateWinstaSecurity for information */
|
|
SECURITY_INFORMATION SecurityInformation;
|
|
DWORD DaclSize;
|
|
PACL Dacl;
|
|
|
|
/* Create the Winlogon SID */
|
|
if (!AllocateAndInitializeSid(&NtAuthority,
|
|
1,
|
|
SECURITY_LOCAL_SYSTEM_RID,
|
|
0, 0, 0, 0, 0, 0, 0,
|
|
&WinlogonSid))
|
|
{
|
|
ERR("AllowWinstaAccessToUser(): Failed to create the Winlogon SID (error code %lu)\n", GetLastError());
|
|
return FALSE;
|
|
}
|
|
|
|
/* Create the admins SID */
|
|
if (!AllocateAndInitializeSid(&NtAuthority,
|
|
2,
|
|
SECURITY_BUILTIN_DOMAIN_RID,
|
|
DOMAIN_ALIAS_RID_ADMINS,
|
|
0, 0, 0, 0, 0, 0,
|
|
&AdminsSid))
|
|
{
|
|
ERR("AllowWinstaAccessToUser(): Failed to create the admins SID (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Create the interactive logon SID */
|
|
if (!AllocateAndInitializeSid(&NtAuthority,
|
|
1,
|
|
SECURITY_INTERACTIVE_RID,
|
|
0, 0, 0, 0, 0, 0, 0,
|
|
&InteractiveSid))
|
|
{
|
|
ERR("AllowWinstaAccessToUser(): Failed to create the interactive SID (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* HACK: Create the network service SID */
|
|
if (!AllocateAndInitializeSid(&NtAuthority,
|
|
1,
|
|
SECURITY_NETWORK_SERVICE_RID,
|
|
0, 0, 0, 0, 0, 0, 0,
|
|
&NetworkServiceSid))
|
|
{
|
|
ERR("AllowWinstaAccessToUser(): Failed to create the network service SID (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/*
|
|
* Build up the DACL size. This includes a number
|
|
* of eight ACEs of four different SIDs. The first ACE
|
|
* gives full winsta access to Winlogon, the second one gives
|
|
* generic access to Winlogon. Such approach is the same
|
|
* for both interactive logon users and logon user as well.
|
|
* Only admins are given limited powers.
|
|
*/
|
|
DaclSize = sizeof(ACL) +
|
|
sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD) + GetLengthSid(WinlogonSid) +
|
|
sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD) + GetLengthSid(WinlogonSid) +
|
|
sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD) + GetLengthSid(AdminsSid) +
|
|
sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD) + GetLengthSid(AdminsSid) +
|
|
sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD) + GetLengthSid(InteractiveSid) +
|
|
sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD) + GetLengthSid(InteractiveSid) +
|
|
sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD) + GetLengthSid(LogonSid) +
|
|
sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD) + GetLengthSid(LogonSid) +
|
|
sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD) + GetLengthSid(NetworkServiceSid) + /* HACK */
|
|
sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD) + GetLengthSid(NetworkServiceSid);
|
|
|
|
/* Allocate the DACL now */
|
|
Dacl = RtlAllocateHeap(RtlGetProcessHeap(),
|
|
HEAP_ZERO_MEMORY,
|
|
DaclSize);
|
|
if (Dacl == NULL)
|
|
{
|
|
ERR("AllowWinstaAccessToUser(): Failed to allocate memory buffer for DACL!\n");
|
|
goto Quit;
|
|
}
|
|
|
|
/* Initialize it */
|
|
if (!InitializeAcl(Dacl, DaclSize, ACL_REVISION))
|
|
{
|
|
ERR("AllowWinstaAccessToUser(): Failed to initialize DACL (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* First ACE -- Give full winsta access to Winlogon */
|
|
if (!AddAccessAllowedAceEx(Dacl,
|
|
ACL_REVISION,
|
|
NO_PROPAGATE_INHERIT_ACE,
|
|
WINSTA_ALL,
|
|
WinlogonSid))
|
|
{
|
|
ERR("AllowWinstaAccessToUser(): Failed to set ACE for Winlogon (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Second ACE -- Give generic access to Winlogon */
|
|
if (!AddAccessAllowedAceEx(Dacl,
|
|
ACL_REVISION,
|
|
INHERIT_ONLY_ACE | OBJECT_INHERIT_ACE | CONTAINER_INHERIT_ACE,
|
|
GENERIC_ACCESS,
|
|
WinlogonSid))
|
|
{
|
|
ERR("AllowWinstaAccessToUser(): Failed to set ACE for Winlogon (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Third ACE -- Give limited winsta access to admins */
|
|
if (!AddAccessAllowedAceEx(Dacl,
|
|
ACL_REVISION,
|
|
NO_PROPAGATE_INHERIT_ACE,
|
|
WINSTA_ADMINS_LIMITED,
|
|
AdminsSid))
|
|
{
|
|
ERR("AllowWinstaAccessToUser(): Failed to set ACE for admins (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Fourth ACE -- Give limited desktop access to admins */
|
|
if (!AddAccessAllowedAceEx(Dacl,
|
|
ACL_REVISION,
|
|
INHERIT_ONLY_ACE | OBJECT_INHERIT_ACE | CONTAINER_INHERIT_ACE,
|
|
DESKTOP_ADMINS_LIMITED,
|
|
AdminsSid))
|
|
{
|
|
ERR("AllowWinstaAccessToUser(): Failed to set ACE for admins (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Fifth ACE -- Give full winsta access to interactive logon users */
|
|
if (!AddAccessAllowedAceEx(Dacl,
|
|
ACL_REVISION,
|
|
NO_PROPAGATE_INHERIT_ACE,
|
|
WINSTA_ALL,
|
|
InteractiveSid))
|
|
{
|
|
ERR("AllowWinstaAccessToUser(): Failed to set ACE for interactive SID (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Sixth ACE -- Give generic access to interactive logon users */
|
|
if (!AddAccessAllowedAceEx(Dacl,
|
|
ACL_REVISION,
|
|
INHERIT_ONLY_ACE | OBJECT_INHERIT_ACE | CONTAINER_INHERIT_ACE,
|
|
GENERIC_ACCESS,
|
|
InteractiveSid))
|
|
{
|
|
ERR("AllowWinstaAccessToUser(): Failed to set ACE for interactive SID (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Seventh ACE -- Give full winsta access to logon user */
|
|
if (!AddAccessAllowedAceEx(Dacl,
|
|
ACL_REVISION,
|
|
NO_PROPAGATE_INHERIT_ACE,
|
|
WINSTA_ALL,
|
|
LogonSid))
|
|
{
|
|
ERR("AllowWinstaAccessToUser(): Failed to set ACE for logon user SID (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Eighth ACE -- Give generic access to logon user */
|
|
if (!AddAccessAllowedAceEx(Dacl,
|
|
ACL_REVISION,
|
|
INHERIT_ONLY_ACE | OBJECT_INHERIT_ACE | CONTAINER_INHERIT_ACE,
|
|
GENERIC_ACCESS,
|
|
LogonSid))
|
|
{
|
|
ERR("AllowWinstaAccessToUser(): Failed to set ACE for logon user SID (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* HACK : Ninenth ACE -- Give full winsta access to network services */
|
|
if (!AddAccessAllowedAceEx(Dacl,
|
|
ACL_REVISION,
|
|
NO_PROPAGATE_INHERIT_ACE,
|
|
WINSTA_ALL,
|
|
NetworkServiceSid))
|
|
{
|
|
ERR("AllowWinstaAccessToUser(): Failed to set ACE for logon network service SID (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* HACK: Tenth ACE -- Give generic access to network services */
|
|
if (!AddAccessAllowedAceEx(Dacl,
|
|
ACL_REVISION,
|
|
INHERIT_ONLY_ACE | OBJECT_INHERIT_ACE | CONTAINER_INHERIT_ACE,
|
|
GENERIC_ACCESS,
|
|
NetworkServiceSid))
|
|
{
|
|
ERR("AllowWinstaAccessToUser(): Failed to set ACE for network service SID (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Initialize the security descriptor */
|
|
if (!InitializeSecurityDescriptor(&AbsoluteSd, SECURITY_DESCRIPTOR_REVISION))
|
|
{
|
|
ERR("AllowWinstaAccessToUser(): Failed to initialize absolute security descriptor (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Set the DACL to descriptor */
|
|
if (!SetSecurityDescriptorDacl(&AbsoluteSd, TRUE, Dacl, FALSE))
|
|
{
|
|
ERR("AllowWinstaAccessToUser(): Failed to set up DACL to absolute security descriptor (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Convert it to self-relative format */
|
|
RelativeSd = ConvertToSelfRelative(&AbsoluteSd);
|
|
if (RelativeSd == NULL)
|
|
{
|
|
ERR("AllowWinstaAccessToUser(): Failed to convert security descriptor to self relative format!\n");
|
|
goto Quit;
|
|
}
|
|
|
|
/* Set new winsta security based on this descriptor */
|
|
SecurityInformation = DACL_SECURITY_INFORMATION;
|
|
if (!SetUserObjectSecurity(WinSta, &SecurityInformation, RelativeSd))
|
|
{
|
|
ERR("AllowWinstaAccessToUser(): Failed to set window station security descriptor (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
Success = TRUE;
|
|
|
|
Quit:
|
|
if (WinlogonSid != NULL)
|
|
{
|
|
FreeSid(WinlogonSid);
|
|
}
|
|
|
|
if (AdminsSid != NULL)
|
|
{
|
|
FreeSid(AdminsSid);
|
|
}
|
|
|
|
if (InteractiveSid != NULL)
|
|
{
|
|
FreeSid(InteractiveSid);
|
|
}
|
|
|
|
/* HACK */
|
|
if (NetworkServiceSid != NULL)
|
|
{
|
|
FreeSid(NetworkServiceSid);
|
|
}
|
|
/* END HACK */
|
|
|
|
if (Dacl != NULL)
|
|
{
|
|
RtlFreeHeap(RtlGetProcessHeap(), 0, Dacl);
|
|
}
|
|
|
|
if (RelativeSd != NULL)
|
|
{
|
|
RtlFreeHeap(RtlGetProcessHeap(), 0, RelativeSd);
|
|
}
|
|
|
|
return Success;
|
|
}
|
|
|
|
/**
|
|
* @brief
|
|
* Assigns access to the specific logon user to
|
|
* the default desktop. Such access is given to
|
|
* the user when it has logged in.
|
|
*
|
|
* @param[in] Desktop
|
|
* A handle to a desktop where the user
|
|
* is given access to it.
|
|
*
|
|
* @param[in] LogonSid
|
|
* A pointer to a logon SID that represents
|
|
* the logged in user in question.
|
|
*
|
|
* @return
|
|
* Returns TRUE if the function has successfully
|
|
* assigned access to the user, FALSE otherwise.
|
|
*/
|
|
BOOL
|
|
AllowDesktopAccessToUser(
|
|
_In_ HDESK Desktop,
|
|
_In_ PSID LogonSid)
|
|
{
|
|
BOOL Success = FALSE;
|
|
SECURITY_DESCRIPTOR AbsoluteSd;
|
|
PSECURITY_DESCRIPTOR RelativeSd = NULL;
|
|
PSID WinlogonSid = NULL, AdminsSid = NULL, InteractiveSid = NULL, NetworkServiceSid = NULL; /* NetworkServiceSid is a HACK, see the comment in CreateWinstaSecurity for information */
|
|
SECURITY_INFORMATION SecurityInformation;
|
|
DWORD DaclSize;
|
|
PACL Dacl;
|
|
|
|
/* Create the Winlogon SID */
|
|
if (!AllocateAndInitializeSid(&NtAuthority,
|
|
1,
|
|
SECURITY_LOCAL_SYSTEM_RID,
|
|
0, 0, 0, 0, 0, 0, 0,
|
|
&WinlogonSid))
|
|
{
|
|
ERR("AllowDesktopAccessToUser(): Failed to create the Winlogon SID (error code %lu)\n", GetLastError());
|
|
return FALSE;
|
|
}
|
|
|
|
/* Create the admins SID */
|
|
if (!AllocateAndInitializeSid(&NtAuthority,
|
|
2,
|
|
SECURITY_BUILTIN_DOMAIN_RID,
|
|
DOMAIN_ALIAS_RID_ADMINS,
|
|
0, 0, 0, 0, 0, 0,
|
|
&AdminsSid))
|
|
{
|
|
ERR("AllowDesktopAccessToUser(): Failed to create the admins SID (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Create the interactive logon SID */
|
|
if (!AllocateAndInitializeSid(&NtAuthority,
|
|
1,
|
|
SECURITY_INTERACTIVE_RID,
|
|
0, 0, 0, 0, 0, 0, 0,
|
|
&InteractiveSid))
|
|
{
|
|
ERR("AllowDesktopAccessToUser(): Failed to create the interactive SID (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* HACK: Create the network service SID */
|
|
if (!AllocateAndInitializeSid(&NtAuthority,
|
|
1,
|
|
SECURITY_NETWORK_SERVICE_RID,
|
|
0, 0, 0, 0, 0, 0, 0,
|
|
&NetworkServiceSid))
|
|
{
|
|
ERR("AllowDesktopAccessToUser(): Failed to create the network service SID (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/*
|
|
* Build up the DACL size. This includes a number
|
|
* of four ACEs of four different SIDs. The first ACE
|
|
* gives full desktop access to Winlogon, the second one gives
|
|
* generic limited desktop access to admins. The last two give
|
|
* full power to both interactive logon users and logon user as
|
|
* well.
|
|
*/
|
|
DaclSize = sizeof(ACL) +
|
|
sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD) + GetLengthSid(WinlogonSid) +
|
|
sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD) + GetLengthSid(AdminsSid) +
|
|
sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD) + GetLengthSid(InteractiveSid) +
|
|
sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD) + GetLengthSid(LogonSid) +
|
|
sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD) + GetLengthSid(NetworkServiceSid); /* HACK */
|
|
|
|
/* Allocate the DACL now */
|
|
Dacl = RtlAllocateHeap(RtlGetProcessHeap(),
|
|
HEAP_ZERO_MEMORY,
|
|
DaclSize);
|
|
if (Dacl == NULL)
|
|
{
|
|
ERR("AllowDesktopAccessToUser(): Failed to allocate memory buffer for DACL!\n");
|
|
goto Quit;
|
|
}
|
|
|
|
/* Initialize it */
|
|
if (!InitializeAcl(Dacl, DaclSize, ACL_REVISION))
|
|
{
|
|
ERR("AllowDesktopAccessToUser(): Failed to initialize DACL (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* First ACE -- Give full desktop access to Winlogon */
|
|
if (!AddAccessAllowedAceEx(Dacl,
|
|
ACL_REVISION,
|
|
0,
|
|
DESKTOP_ALL,
|
|
WinlogonSid))
|
|
{
|
|
ERR("AllowDesktopAccessToUser(): Failed to set ACE for Winlogon (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Second ACE -- Give limited desktop access to admins */
|
|
if (!AddAccessAllowedAceEx(Dacl,
|
|
ACL_REVISION,
|
|
0,
|
|
DESKTOP_ADMINS_LIMITED,
|
|
AdminsSid))
|
|
{
|
|
ERR("AllowDesktopAccessToUser(): Failed to set ACE for admins (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Third ACE -- Give full desktop access to interactive logon users */
|
|
if (!AddAccessAllowedAceEx(Dacl,
|
|
ACL_REVISION,
|
|
0,
|
|
DESKTOP_ALL,
|
|
InteractiveSid))
|
|
{
|
|
ERR("AllowDesktopAccessToUser(): Failed to set ACE for interactive SID (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Fourth ACE -- Give full desktop access to logon user */
|
|
if (!AddAccessAllowedAceEx(Dacl,
|
|
ACL_REVISION,
|
|
0,
|
|
DESKTOP_ALL,
|
|
LogonSid))
|
|
{
|
|
ERR("AllowDesktopAccessToUser(): Failed to set ACE for logon user SID (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* HACK: Fifth ACE -- Give full desktop to network services */
|
|
if (!AddAccessAllowedAceEx(Dacl,
|
|
ACL_REVISION,
|
|
0,
|
|
DESKTOP_ALL,
|
|
NetworkServiceSid))
|
|
{
|
|
ERR("AllowDesktopAccessToUser(): Failed to set ACE for network service SID (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Initialize the security descriptor */
|
|
if (!InitializeSecurityDescriptor(&AbsoluteSd, SECURITY_DESCRIPTOR_REVISION))
|
|
{
|
|
ERR("AllowDesktopAccessToUser(): Failed to initialize absolute security descriptor (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Set the DACL to the descriptor */
|
|
if (!SetSecurityDescriptorDacl(&AbsoluteSd, TRUE, Dacl, FALSE))
|
|
{
|
|
ERR("AllowDesktopAccessToUser(): Failed to set up DACL to absolute security descriptor (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Conver it to self-relative format */
|
|
RelativeSd = ConvertToSelfRelative(&AbsoluteSd);
|
|
if (RelativeSd == NULL)
|
|
{
|
|
ERR("AllowDesktopAccessToUser(): Failed to convert security descriptor to self relative format!\n");
|
|
goto Quit;
|
|
}
|
|
|
|
/* Assign new security to desktop based on this descriptor */
|
|
SecurityInformation = DACL_SECURITY_INFORMATION;
|
|
if (!SetUserObjectSecurity(Desktop, &SecurityInformation, RelativeSd))
|
|
{
|
|
ERR("AllowDesktopAccessToUser(): Failed to set desktop security descriptor (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
Success = TRUE;
|
|
|
|
Quit:
|
|
if (WinlogonSid != NULL)
|
|
{
|
|
FreeSid(WinlogonSid);
|
|
}
|
|
|
|
if (AdminsSid != NULL)
|
|
{
|
|
FreeSid(AdminsSid);
|
|
}
|
|
|
|
if (InteractiveSid != NULL)
|
|
{
|
|
FreeSid(InteractiveSid);
|
|
}
|
|
|
|
/* HACK */
|
|
if (NetworkServiceSid != NULL)
|
|
{
|
|
FreeSid(NetworkServiceSid);
|
|
}
|
|
/* END HACK */
|
|
|
|
if (Dacl != NULL)
|
|
{
|
|
RtlFreeHeap(RtlGetProcessHeap(), 0, Dacl);
|
|
}
|
|
|
|
if (RelativeSd != NULL)
|
|
{
|
|
RtlFreeHeap(RtlGetProcessHeap(), 0, RelativeSd);
|
|
}
|
|
|
|
return Success;
|
|
}
|
|
|
|
/**
|
|
* @brief
|
|
* Assigns both window station and desktop access
|
|
* to the specific session currently active on the
|
|
* system.
|
|
*
|
|
* @param[in] Session
|
|
* A pointer to an active session.
|
|
*
|
|
* @return
|
|
* Returns TRUE if the function has successfully
|
|
* assigned access to the current session, FALSE otherwise.
|
|
*/
|
|
BOOL
|
|
AllowAccessOnSession(
|
|
_In_ PWLSESSION Session)
|
|
{
|
|
BOOL Success = FALSE;
|
|
DWORD Index, SidLength, GroupsLength = 0;
|
|
PTOKEN_GROUPS TokenGroup = NULL;
|
|
PSID LogonSid;
|
|
|
|
/* Get required buffer size and allocate the TOKEN_GROUPS buffer */
|
|
if (!GetTokenInformation(Session->UserToken,
|
|
TokenGroups,
|
|
TokenGroup,
|
|
0,
|
|
&GroupsLength))
|
|
{
|
|
if (GetLastError() != ERROR_INSUFFICIENT_BUFFER)
|
|
{
|
|
ERR("AllowAccessOnSession(): Unexpected error code returned, must be ERROR_INSUFFICIENT_BUFFER (error code %lu)\n", GetLastError());
|
|
return FALSE;
|
|
}
|
|
|
|
TokenGroup = RtlAllocateHeap(RtlGetProcessHeap(), HEAP_ZERO_MEMORY, GroupsLength);
|
|
if (TokenGroup == NULL)
|
|
{
|
|
ERR("AllowAccessOnSession(): Failed to allocate memory buffer for token group!\n");
|
|
return FALSE;
|
|
}
|
|
}
|
|
|
|
/* Get the token group information from the access token */
|
|
if (!GetTokenInformation(Session->UserToken,
|
|
TokenGroups,
|
|
TokenGroup,
|
|
GroupsLength,
|
|
&GroupsLength))
|
|
{
|
|
ERR("AllowAccessOnSession(): Failed to retrieve the token group information (error code %lu)\n", GetLastError());
|
|
goto Quit;
|
|
}
|
|
|
|
/* Loop through the groups to find the logon SID */
|
|
for (Index = 0; Index < TokenGroup->GroupCount; Index++)
|
|
{
|
|
if ((TokenGroup->Groups[Index].Attributes & SE_GROUP_LOGON_ID)
|
|
== SE_GROUP_LOGON_ID)
|
|
{
|
|
LogonSid = TokenGroup->Groups[Index].Sid;
|
|
break;
|
|
}
|
|
}
|
|
|
|
/* Allow window station access to this user within this session */
|
|
if (!AllowWinstaAccessToUser(Session->InteractiveWindowStation, LogonSid))
|
|
{
|
|
ERR("AllowAccessOnSession(): Failed to allow winsta access to the logon user!\n");
|
|
goto Quit;
|
|
}
|
|
|
|
/* Allow application desktop access to this user within this session */
|
|
if (!AllowDesktopAccessToUser(Session->ApplicationDesktop, LogonSid))
|
|
{
|
|
ERR("AllowAccessOnSession(): Failed to allow application desktop access to the logon user!\n");
|
|
goto Quit;
|
|
}
|
|
|
|
/* Get the length of this logon SID */
|
|
SidLength = GetLengthSid(LogonSid);
|
|
|
|
/* Assign the window station to this logged in user */
|
|
if (!SetWindowStationUser(Session->InteractiveWindowStation,
|
|
&Session->LogonId,
|
|
LogonSid,
|
|
SidLength))
|
|
{
|
|
ERR("AllowAccessOnSession(): Failed to assign the window station to the logon user!\n");
|
|
goto Quit;
|
|
}
|
|
|
|
Success = TRUE;
|
|
|
|
Quit:
|
|
if (TokenGroup != NULL)
|
|
{
|
|
RtlFreeHeap(RtlGetProcessHeap(), 0, TokenGroup);
|
|
}
|
|
|
|
return Success;
|
|
}
|
|
|
|
/* EOF */
|