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eventsCommon.cpp
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eventsCommon.cpp
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/*
SysmonCommon
Copyright (c) Microsoft Corporation
All rights reserved.
MIT License
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the ""Software""), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED *AS IS*, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
//====================================================================
//
// EventsCommon.c
//
// Implements event handling depending of windows versions
//
//====================================================================
#include "stdafx.h"
#include "rules.h"
#include "eventsCommon.h"
#if defined _WIN64 || defined _WIN32
#include <Objbase.h>
#include <WinEvt.h>
#include <VersionHelper.h>
#include "dll.h"
#elif defined __linux__
#include <pthread.h>
#include "linuxHelpers.h"
#include <sys/time.h>
#include <pwd.h>
#include <syslog.h>
extern "C" {
#include "outputxml.h"
}
#endif
//
// Command line can be up to 0x7FFE but event log strings have a limit
// of 31839 characters (https://docs.microsoft.com/en-us/windows/desktop/api/winbase/nf-winbase-reporteventa)
//
#define PATH_MAX_SIZE 31839
#define MAX_EVENT_PACKET_SIZE 62000
#if defined __linux__
extern "C" {
VOID syslogHelper( int priority, const char* fmt, char* msg );
}
#elif defined _WIN64 || defined _WIN32
#include "events.h"
extern PFN_EVENT_WRITE PfnEventWrite;
#endif
REGHANDLE g_Event = 0;
HANDLE g_hEventSource = NULL;
#if defined _WIN64 || defined _WIN32
BOOLEAN bPreVista = FALSE;
#elif defined __linux__
// define Linux as being 'pre-Vista' as it helps without event output
BOOLEAN bPreVista = TRUE;
#endif
BOOLEAN bInitialized = FALSE;
ULONG machineId = 0;
//--------------------------------------------------------------------
//
// ProcessGetCache
//
// Fetch a process cache entry
//
//--------------------------------------------------------------------
PPROCESS_CACHE_INFORMATION ProcessCache::ProcessGet(
_In_ DWORD ProcessId,
_In_ const PLARGE_INTEGER time,
_In_opt_ PVOID ProcessObject
)
{
PPROCESS_CACHE_INFORMATION ret = NULL;
LockCache();
//
// search for process ID in unordered map
//
auto processEntry = _processCache.find( ProcessId );
if( processEntry != _processCache.end() ) {
//
// iterate over list items for this process ID
//
for( auto ¤t : processEntry->second ) {
// #444 If a process object was provided, check for a match against this in addition to the PID
if( (ProcessObject == NULL) ||
(current.data->m_ProcessObject == NULL) ||
(current.data->m_ProcessObject == ProcessObject) ) {
if( time != NULL ) {
//
// If I didn't select the entry or the time of the event was
// before the process was removed
//
if( ret == NULL ) {
//
// Only if time makes sense, else we will select a wrong old entry
// and the latest will be skipped
//
if( (current.removedTime.QuadPart == 0 || // If the current entry is still open
(ULONG64)time->QuadPart < (ULONG64)(current.removedTime.QuadPart + NT_500_MS)) && // Or it has now terminated but terminated after the process creation time
// the half second buffer is because we have seen network events appear marginally later than the process terminate event
(time->QuadPart >= current.data->m_CreateTime.QuadPart) ) { // #444. We validate the end of the time window but not the start..
ret = ¤t;
}
} else if( current.removedTime.QuadPart != 0 && // The process has terminadumpted
(ULONG64)time->QuadPart < (ULONG64)current.removedTime.QuadPart && // The process terminated after our process creation time
time->QuadPart >= current.data->m_CreateTime.QuadPart && // #444 Validate the start of the time window too
(ret->removedTime.QuadPart == 0 || // we are either superseding a candidate that is still open
(ULONG64)ret->removedTime.QuadPart > ( ULONG64 )current.removedTime.QuadPart) ) { // or we are superseding a process with a wider windows than the current candidate
ret = ¤t;
}
} else {
//
// Select the latest available;
//
if( ret == NULL ) {
ret = ¤t;
} else if( (current.removedTime.QuadPart == 0) ||
((ret->removedTime.QuadPart != 0) &&
((ULONG64)ret->removedTime.QuadPart < (ULONG64)current.removedTime.QuadPart)) ) {
ret = ¤t;
}
break;
}
}
}
}
UnlockCache();
return ret;
}
//--------------------------------------------------------------------
//
// ProcessCache::RemoveEntries
//
// Remove all entries from the cache
//
//--------------------------------------------------------------------
void ProcessCache::RemoveEntries()
{
LockCache();
//
// for every entry in the cache (removing after each iteration)
//
for( auto cacheEntry = _processCache.begin(); cacheEntry != _processCache.end(); cacheEntry = _processCache.erase( cacheEntry ) ) {
//
// iterate over list items for this process ID
//
for( auto ¤t : cacheEntry->second ) {
free( current.data );
}
}
UnlockCache();
}
//--------------------------------------------------------------------
//
// ProcessCache::ProcessRemove
//
// Remove an entry from the cache
//
//--------------------------------------------------------------------
void ProcessCache::ProcessRemove(
_In_ DWORD ProcessId,
_In_ GUID* ProcessGuid,
_In_opt_ PLARGE_INTEGER EventTime
)
{
LARGE_INTEGER currentTime;
if( EventTime == NULL ) {
GetSystemTimeAsLargeInteger( ¤tTime );
EventTime = ¤tTime;
}
LockCache();
//
// search for process ID in unordered map
//
auto processEntry = _processCache.find( ProcessId );
if( processEntry != _processCache.end() ) {
//
// iterate over list items for this process ID
//
for( auto ¤t : processEntry->second) {
//
// Mark the entry as removed, but keep it around in case
// we get delayed ETW events that reference it
//
current.removedTime.QuadPart = EventTime->QuadPart;
}
_expiringProcesses.emplace( EventTime->QuadPart, ProcessId );
}
PurgeExpired( EventTime );
UnlockCache();
}
void ProcessCache::PurgeExpired( PLARGE_INTEGER EventTime )
{
while( !_expiringProcesses.empty() && Expired( _expiringProcesses.top().time, EventTime->QuadPart ) ) {
CacheEntryToExpire oldest = _expiringProcesses.top();
_expiringProcesses.pop();
auto processes = _processCache.find( oldest.pid );
if( processes != _processCache.end() ) {
for( auto &process : processes->second ) {
free( process.data );
}
_processCache.erase( oldest.pid );
}
}
}
//--------------------------------------------------------------------
//
// ProcessCache::ProcessAdd
//
// Add a process record to the process cache
//
//--------------------------------------------------------------------
void ProcessCache::ProcessAdd(
_In_ GUID uniqueProcessGUID,
_In_ PSYSMON_EVENT_HEADER event
)
{
PROCESS_CACHE_INFORMATION cacheEntry;
PSYSMON_PROCESS_CREATE data;
SIZE_T dataSize;
data = &event->m_EventBody.m_ProcessCreateEvent;
dataSize = event->m_EventSize - offsetof( SYSMON_EVENT_HEADER, m_EventBody );
cacheEntry.data = static_cast<PSYSMON_PROCESS_CREATE>( malloc( dataSize ) );
if( cacheEntry.data != NULL ) {
LockCache();
memcpy( cacheEntry.data, data, dataSize );
cacheEntry.uniqueProcessGUID = uniqueProcessGUID;
cacheEntry.removedTime.QuadPart = 0;
cacheEntry.dnsQueryCache = {};
ProcessRemove( data->m_ProcessId, &uniqueProcessGUID, NULL );
auto processEntry = _processCache.find( data->m_ProcessId );
if( processEntry == _processCache.end() ) {
_processCache.emplace( data->m_ProcessId, CacheEntries{ cacheEntry } );
} else {
processEntry->second.push_front( cacheEntry );
}
UnlockCache();
}
}
bool ProcessCache::Empty()
{
LockCache();
bool ret = _processCache.empty();
UnlockCache();
return ret;
}
#if defined _WIN64 || defined _WIN32
bool ProcessCache::DnsEntryAdd( DWORD ProcessId, PDNS_QUERY_DATA DnsEntry )
{
LockCache();
auto processInfo = ProcessGet( ProcessId, NULL, NULL );
if( processInfo != NULL ) {
for( auto &cachedQuery : processInfo->dnsQueryCache) {
if( !_tcsicmp( cachedQuery.QueryName, DnsEntry->QueryName ) &&
!_tcsicmp( cachedQuery.QueryResult, DnsEntry->QueryResult ) &&
!_tcsicmp( cachedQuery.QueryStatus, DnsEntry->QueryStatus ) ) {
UnlockCache();
return false;
}
}
//
// Add to the cache
//
if( processInfo->dnsQueryCache.size() == DNS_CACHE_LIMIT ) {
processInfo->dnsQueryCache.pop_back();
}
// Performing a copy here, just in case.
processInfo->dnsQueryCache.push_front( *DnsEntry );
}
UnlockCache();
return true;
}
#endif
//
// Maximum killed processes in the cache
//
#define PROCESS_CACHE_FREE_MAX 400
#ifdef __cplusplus
extern "C" {
#endif
extern HANDLE g_hDriver;
#ifdef __cplusplus
}
#endif
//
// Default values
//
TCHAR DefaultString[] = _T("-");
GUID DefaultGuid = {0,};
//--------------------------------------------------------------------
//
// EventDataDescCreateS
//
// Helper function for EventDataDescCreate handling with strings
//
//--------------------------------------------------------------------
VOID EventDataDescCreateS(
_In_ PEVENT_DATA_DESCRIPTOR Data,
_In_ const TCHAR* String
)
{
if( String == NULL ) {
String = _T("NULL");
}
EventDataDescCreate( Data, (PVOID)String, (ULONG)((_tcslen(String) + 1) * sizeof(TCHAR)) );
}
//--------------------------------------------------------------------
//
// GenerateUniqueId
//
// Get a unique GUID for this event on this machine
// Structure:
// - machineID (last part of the machine account SID)
// - Time of the event in seconds
// - TokenId (unique object ID) | type of the object
//
//--------------------------------------------------------------------
GUID GenerateUniqueId(
_In_ PLARGE_INTEGER timestamp,
_In_ ULONGLONG ProcessStartKey,
OBJECT_TYPE type
)
{
GUID result = {0,};
DWORD seconds = 0;
PBYTE pResult = (PBYTE)&result;
#if defined _WIN64 || defined _WIN32
RtlTimeToSecondsSince1970( timestamp, &seconds );
#elif defined __linux__
// timestamp in 100ns intervals since epoch
seconds = LargeTimeToSeconds( timestamp );
#endif
*(DWORD*) pResult = machineId;
pResult += sizeof(DWORD);
*(DWORD*) pResult = seconds;
pResult += sizeof(DWORD);
*(DWORD64*) pResult = ProcessStartKey;
return result;
}
//--------------------------------------------------------------------
//
// GenerateUniquePGUID
//
// Generate a unique GUID for the process
//
//--------------------------------------------------------------------
void GenerateUniquePGUID(
_In_ GUID* pguid,
_In_ PSYSMON_EVENT_HEADER event,
_In_ BOOLEAN Cache
)
{
GUID g;
PSYSMON_PROCESS_CREATE data;
data = &event->m_EventBody.m_ProcessCreateEvent;
g = GenerateUniqueId( &data->m_CreateTime, data->m_ProcessKey, Process );
// Update the cache
if( Cache ) {
ProcessCache::Instance().ProcessAdd( g, event );
}
*pguid = g;
}
//--------------------------------------------------------------------
//
// FetchUniquePGUID
//
// Fetch a unique GUID for the process from the cache
//
//--------------------------------------------------------------------
void FetchUniquePGUID(
_Out_ GUID* pguid,
_In_ ULONG ProcessId,
_In_ BOOLEAN UpdateCache,
_In_ PLARGE_INTEGER time
)
{
PPROCESS_CACHE_INFORMATION cache;
UCHAR buffer[16386];
BOOL result;
PSYSMON_EVENT_HEADER event;
ProcessCache::Instance().LockCache();
cache = ProcessCache::Instance().ProcessGet( ProcessId, time, NULL );
if( cache ) {
*pguid = cache->uniqueProcessGUID;
ProcessCache::Instance().UnlockCache();
} else {
ProcessCache::Instance().UnlockCache();
#if defined _WIN64 || defined _WIN32
DWORD bytesReturned = 1;
UPDATE_CACHE cacheRequest;
cacheRequest.ProcessId = ProcessId;
cacheRequest.UpdateCache = UpdateCache;
result = DeviceIoControl( g_hDriver, IOCTL_SYSMON_PROCESS_CACHE, &cacheRequest, sizeof(cacheRequest),
buffer, sizeof(buffer), &bytesReturned, NULL );
if( result ) {
D_ASSERT(bytesReturned > 0);
event = (PSYSMON_EVENT_HEADER) buffer;
GenerateUniquePGUID( pguid, event, UpdateCache );
} else {
DBG_MODE( _tprintf( _T("PROCESS_CACHE_REQUEST failed with %d\n"), GetLastError() ) );
}
#elif defined __linux__
result = GetProcess( (PSYSMON_EVENT_HEADER) buffer, sizeof(buffer), ProcessId );
if( result ) {
event = (PSYSMON_EVENT_HEADER) buffer;
GenerateUniquePGUID( pguid, event, UpdateCache );
} else {
DBG_MODE( _tprintf( _T("PROCESS_CACHE_REQUEST failed\n") ) );
}
#endif
}
}
//--------------------------------------------------------------------
//
// GenerateUniqueSGUID
//
// Generate a unique GUID for the session
//
//--------------------------------------------------------------------
void GenerateUniqueSGUID(
_In_ GUID* sguid,
_In_ LUID* authenticationId
)
{
GUID g;
LARGE_INTEGER timestamp = {0,};
#if defined _WIN64 || defined _WIN32
NTSTATUS status;
PSECURITY_LOGON_SESSION_DATA sessionData;
status = LsaGetLogonSessionData( authenticationId, &sessionData );
if (NT_SUCCESS(status))
{
timestamp = sessionData->LogonTime;
LsaFreeReturnBuffer( sessionData );
}
#elif defined __linux__
timestamp = GetLogonTime( authenticationId );
#endif
g = GenerateUniqueId( ×tamp, * (PULONGLONG) authenticationId, Session );
*sguid = g;
}
//--------------------------------------------------------------------
//
// RefreshProcessCache
//
// Refresh the process cache from the current process list
//
//--------------------------------------------------------------------
VOID RefreshProcessCache(
VOID
)
{
PDWORD processList = NULL;
GUID tmp;
DWORD i;
// 16384 entries should be large enough for most systems, but still only uses
// 64KB of RAM.
DWORD processSize = 16384 * sizeof( DWORD );
DWORD processUsed = 0;
for( i = 0; i < 5; i++ ) {
processList = (PDWORD)malloc( processSize );
if( processList == NULL ) {
PrintErrorEx( (PTCHAR)_T( __FUNCTION__ ), 0, (PTCHAR)_T( "Out of memory condition" ) );
return;
}
// Check that EnumProcesses succeeds AND that we have all the processes available
// If EnumProcesses fails, for simplicity handle it in the same way as if the buffer
// is too small. The extra memory usage is inconsequential - total memory usage would
// reach 128KB if it fails 5 times in a row.
if( EnumProcesses( processList, processSize, &processUsed ) && processUsed < processSize ) {
break;
}
// If 16K entries is too small, we need to jump a reasonable amount to ensure
// we find a suitable size before the loop expires.
processSize += 4096 * sizeof( DWORD );
free( processList );
processList = NULL;
}
if( processList == NULL ) {
PrintErrorEx( (PTCHAR)_T( __FUNCTION__ ), 0, (PTCHAR)_T( "Failed to udpate the process cache on start" ) );
return;
}
//
// Fetch each process GUID to update the cache
//
for( i = 0; i < (processUsed / sizeof( DWORD )); i++ ) {
FetchUniquePGUID( &tmp, processList[i], TRUE, NULL );
}
free( processList );
}
//--------------------------------------------------------------------
//
// TimestampFormat
//
// Format a timestamp to local time for event reporting
//
//--------------------------------------------------------------------
VOID TimestampFormat(
_Out_ PTCHAR buffer,
_In_ SIZE_T bufferCount,
_In_ PLARGE_INTEGER timestamp
)
{
#if defined _WIN64 || defined _WIN32
SYSTEMTIME timeFields;
FILETIME fileTime;
fileTime.dwLowDateTime = timestamp->LowPart;
fileTime.dwHighDateTime = (DWORD)timestamp->HighPart;
if( FileTimeToSystemTime( &fileTime, &timeFields ) ) {
_stprintf_s( buffer, bufferCount, _T("%04u-%02u-%02u %02u:%02u:%02u.%03u"),
timeFields.wYear, timeFields.wMonth, timeFields.wDay,
timeFields.wHour, timeFields.wMinute, timeFields.wSecond, timeFields.wMilliseconds );
} else {
_stprintf_s( buffer, bufferCount, _T("Incorrect filetime: 0x%I64x"),
timestamp->QuadPart );
}
#elif defined __linux__
// time in 100ns intervals since epoch
struct tm timeFields;
time_t fileTime = LargeTimeToSeconds( timestamp );
if ( gmtime_r(&fileTime, &timeFields) ) {
snprintf( buffer, bufferCount, "%04u-%02u-%02u %02u:%02u:%02u.%03u",
timeFields.tm_year + 1900, timeFields.tm_mon + 1, timeFields.tm_mday,
timeFields.tm_hour, timeFields.tm_min, timeFields.tm_sec,
LargeTimeMilliseconds( timestamp ));
} else {
_stprintf_s( buffer, bufferCount, _T("Incorrect filetime: 0x%" PRIx64),
timestamp->QuadPart );
}
#endif
}
//--------------------------------------------------------------------
//
// ExtGetPtr
//
// Get a pointer to the target extension of the event
//
//--------------------------------------------------------------------
PVOID ExtGetPtr(
_In_ PULONG extensionsSizes,
_In_ PVOID extensions,
_In_ ULONG index,
_Out_ PULONG retSize
)
{
ULONG i, size;
PBYTE ptr = (PBYTE) extensions;
size = extensionsSizes[index];
if( retSize ) {
*retSize = size;
}
if( size == 0 ) {
return NULL;
}
for( i = 0; i < index; i++ ) {
ptr += extensionsSizes[i];
}
return ptr;
}
//--------------------------------------------------------------------
//
// ExtGetEscapeString
//
// Extract a string from an extension
//
//--------------------------------------------------------------------
PTCHAR ExtGetEscapeString(
_In_ PULONG extensionsSizes,
_In_ PVOID extensions,
_In_ ULONG index
)
{
ULONG size, i, escapes = 0;
PVOID ptr;
PTCHAR str, strPtr;
ptr = ExtGetPtr( extensionsSizes, extensions, index, &size );
if( ptr == NULL || size < sizeof( TCHAR ) ) {
return NULL;
}
if( (size % sizeof( TCHAR )) != 0 ) {
size--;
}
// Count % characters
for (i = 0; i < size / sizeof(TCHAR); i++) {
if( ((PTCHAR) ptr)[i] == '%' )
escapes++;
}
str = strPtr = (PTCHAR) malloc( size + (escapes * sizeof( TCHAR )) + sizeof( TCHAR ) );
if( str != NULL ) {
size /= sizeof( TCHAR );
for( i = 0; i < size; i++ ) {
*strPtr = ((PTCHAR) ptr)[i];
strPtr++;
if( ((PTCHAR) ptr)[i] == '%' ) {
*strPtr = '%';
strPtr++;
}
}
*strPtr = 0;
}
return str;
}
//--------------------------------------------------------------------
//
// ExtGetAnsiString
//
// Extract a string from an extension
//
//--------------------------------------------------------------------
PWCHAR ExtGetAnsiString(
_In_ PULONG extensionsSizes,
_In_ PVOID extensions,
_In_ ULONG index,
_In_ PULONG size
)
{
ULONG origSize;
PVOID ptr;
PWCHAR str;
ptr = ExtGetPtr( extensionsSizes, extensions, index, &origSize );
if( ptr == NULL || origSize < sizeof( TCHAR ) ) {
return NULL;
}
#if defined _WIN64 || defined _WIN32
*size = MultiByteToWideChar( CP_ACP, MB_PRECOMPOSED, (LPCSTR) ptr, origSize, NULL, 0 );
#elif defined __linux__
*size = UTF8toUTF16( NULL, (LPCSTR) ptr, 0 );
#endif
if( *size == 0 ) {
return NULL;
}
*size = *size * sizeof( WCHAR );
str = (PWCHAR)malloc( *size );
if( str != NULL ) {
#if defined _WIN64 || defined _WIN32
MultiByteToWideChar( CP_ACP, MB_PRECOMPOSED, (LPCSTR)ptr, origSize, str, *size );
#elif defined __linux__
UTF8toUTF16( str, (LPCSTR)ptr, *size );
#endif
}
return str;
}
//--------------------------------------------------------------------
//
// ExtGetString
//
// Extract a string from an extension
//
//--------------------------------------------------------------------
PTCHAR ExtGetString(
_In_ PULONG extensionsSizes,
_In_ PVOID extensions,
_In_ ULONG index
)
{
ULONG size;
PVOID ptr;
PTCHAR str;
ptr = ExtGetPtr( extensionsSizes, extensions, index, &size );
if( ptr == NULL || size < sizeof(TCHAR) ) {
return NULL;
}
if( (size % sizeof(TCHAR)) != 0 ) {
size--;
}
str = (PTCHAR) malloc( size + sizeof(TCHAR) );
if( str != NULL ) {
size /= sizeof(TCHAR);
_tcsncpy( str, (PTCHAR) ptr, size );
str[size] = 0;
}
return str;
}
//--------------------------------------------------------------------
//
// IsNullTerminated
//
// Check if the string is null terminated
//
//--------------------------------------------------------------------
BOOLEAN IsNullTerminated(
_In_ PVOID ptr,
_In_ ULONG size
)
{
if( size == 0 ) {
return FALSE;
}
PTCHAR str = (PTCHAR)ptr;
size /= sizeof(TCHAR);
return ( str[size-1] == 0 );
}
//--------------------------------------------------------------------
//
// DupStringWithoutNullChar
//
// Duplicate a string without null char bound
//
//--------------------------------------------------------------------
PTCHAR DupStringWithoutNullChar(
_In_ PTCHAR input,
_In_ ULONG sizeInByte
)
{
PTCHAR str;
if( input == NULL || sizeInByte < sizeof(TCHAR) ) {
return NULL;
}
if( (sizeInByte % sizeof(TCHAR)) != 0 ) {
sizeInByte--;
}
if( IsNullTerminated( input, sizeInByte ) ) {
return _tcsdup( input );
}
str = (PTCHAR) malloc( sizeInByte + sizeof(TCHAR) );
if( str == NULL ) {
return NULL;
}
ZeroMemory( str, sizeInByte + sizeof(TCHAR) );
_tcsncpy( str, input, sizeInByte / sizeof(TCHAR) );
return str;
}
//--------------------------------------------------------------------
//
// ReplaceAndDup
//
// Replace a part of the string and dup it
//
//--------------------------------------------------------------------
PTCHAR ReplaceAndDup(
_In_ PTCHAR Input,
_In_ ULONG SizeInBytes,
_In_ ULONG Offset,
_In_ ULONG SubCch,
_In_ PTCHAR Replacement
)
{
ULONG newSize, replaceSize, sizeCch;
PTCHAR str, pos;
if( Input == NULL || SizeInBytes < sizeof(TCHAR) ) {
return NULL;
}
sizeCch = SizeInBytes / sizeof(TCHAR);
if( sizeCch <= Offset || sizeCch < (Offset + SubCch) ) {
return NULL;
}
replaceSize = (ULONG)_tcslen( Replacement );
newSize = sizeCch + replaceSize - SubCch;
//
// Need a null char?
//
if( sizeCch < 2 || Input[sizeCch-1] != 0 ) {
newSize++;
}
newSize *= sizeof(TCHAR);
str = (PTCHAR) malloc( newSize );
if( str == NULL ) {
return NULL;
}
ZeroMemory( str, newSize );
//
// Compute the final string with the replacement
//
pos = str;
memcpy( pos, Input, Offset * sizeof(TCHAR) );
pos += Offset;
D_ASSERT( pos < (str + newSize/sizeof(TCHAR)) );
memcpy( pos, Replacement, replaceSize * sizeof(TCHAR) );
pos += replaceSize;
D_ASSERT( pos < (str + newSize/sizeof(TCHAR)) );
D_ASSERT( pos + (sizeCch - Offset - SubCch) <= (str + newSize/sizeof(TCHAR)) );
memcpy( pos, Input + Offset + SubCch, (sizeCch - Offset - SubCch) * sizeof(TCHAR) );
return str;
}
//--------------------------------------------------------------------
//
// ExtTranslateNtPath
//
// Extract a nt path string from an extension
//
//--------------------------------------------------------------------
PTCHAR ExtTranslateNtPath(
_In_ PULONG extensionsSizes,
_In_ PVOID extensions,
_In_ ULONG index
)
{
ULONG size;
PTCHAR ptr;
ptr = (PTCHAR) ExtGetPtr( extensionsSizes, extensions, index, &size );
if( ptr == NULL ) {
return NULL;
}
#if defined _WIN64 || defined _WIN32
return TranslateNtPath( ptr, size );
#elif defined __linux__
return DupStringWithoutNullChar( ptr, size );
#endif
}
//--------------------------------------------------------------------
//
// TrimStringIfNeeded
//
// Handle trimming of image paths if needed
//
//--------------------------------------------------------------------
BOOLEAN TrimStringIfNeeded(
_In_ PTCHAR path
)
{
if( path != NULL && _tcslen( path ) > PATH_MAX_SIZE ) {
path[PATH_MAX_SIZE-3] =