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xml.cpp
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xml.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.
*/
//====================================================================
//
// Xml.cpp
//
// Handle XML parsing, validation and registry writing for
// configuration files
//
//====================================================================
#include "stdafx.h"
#include <libxml/parser.h>
#include <libxml/tree.h>
#include <libxml/xpath.h>
#include <libxml/xpathInternals.h>
#if defined _WIN64 || defined _WIN32
#include <atlbase.h>
#endif
#include <string>
#include "sysmonevents.h"
#include "xml.h"
#include "rules.h"
#if defined _WIN64 || defined _WIN32
#define ALIGN_DOWN_BY(length, alignment) \
((ULONG_PTR)(length) & ~(alignment - 1))
#define ALIGN_UP_BY(length, alignment) \
(ALIGN_DOWN_BY(((ULONG_PTR)(length) + alignment - 1), alignment))
#elif defined __linux__
#define ALIGN_DOWN_BY(length, alignment) \
((uint64_t)(length) & ~((uint64_t)alignment - 1))
#define ALIGN_UP_BY(length, alignment) \
(ALIGN_DOWN_BY(((uint64_t)(length) + alignment - 1), (uint64_t)alignment))
#endif
//--------------------------------------------------------------------
//
// ParseVersionString
//
// Parse the version string to a ULONG
//
//--------------------------------------------------------------------
ULONG
ParseVersionString(
_In_ PCHAR version
)
{
double dblVersion;
char tmp[40];
ULONG acc, cur, ret;
PCHAR pos;
//
// Normalize the version number
//
dblVersion = std::stod( version );
snprintf( tmp, _countof( tmp ), "%.2f", dblVersion );
acc = ret = 0;
for( pos = tmp; *pos != 0; pos++ ) {
if( *pos == '.' ) {
if( ret != 0 ) {
return (ULONG)-1;
}
ret = (acc << 16);
acc = 0;
// Starts at 1.0
if( ret == 0 ) {
break;
}
} else {
if( *pos < '0' || *pos > '9' ) {
return (ULONG)-1;
}
cur = (ULONG)(*pos - '0');
if( cur == 0 && acc == 0 && ret == 0 ) {
return (ULONG)-1;
}
acc = (acc * 10) + cur;
if( acc > 0xFFFF ) {
return (ULONG)-1;
}
}
}
ret |= acc;
//
// No seperation
//
if( ret < 0xFFFF ) {
ret <<= 16;
}
if( ret == 0 ) {
return (ULONG)-1;
}
return ret;
}
//
// Class to build the rule blob while ensuring offsets are correctly updated.
//
class RuleBuilder
{
private:
PVOID blob;
ULONG blobSize;
ULONG blobAllocated;
ULONG blobVersion;
ULONG schemaVersion;
const ULONG steps = 0x1000;
ULONG lastEventOffset; // Used to chain events
ULONG lastFilterOffset; // Used to chain filters
ULONG prevBlobSize;
ULONG prevLastEventOffset;
ULONG prevLastFilterOffset;
ULONG aggregationOffset; // Used to track the current aggregation when adding filters..
//
// Grow the blob buffer
//
HRESULT
Grow(
_In_ ULONG Bytes
)
{
ULONG remain = (blobAllocated - blobSize);
if( Bytes == 0 || Bytes <= remain ) {
return S_OK;
}
ULONG toAlloc = Bytes > steps ? Bytes : steps;
toAlloc += blobAllocated;
if( toAlloc < blobAllocated ) {
return E_OUTOFMEMORY;
}
PVOID newAlloc = NULL;
if( blob == NULL ) {
newAlloc = malloc( toAlloc );
} else {
newAlloc = realloc( blob, toAlloc );
}
if( newAlloc == NULL ) {
return E_OUTOFMEMORY;
}
if( blob == NULL ) {
ZeroMemory( newAlloc, toAlloc );
} else {
ZeroMemory( (PBYTE)newAlloc + blobSize, toAlloc - blobSize );
}
blob = newAlloc;
blobAllocated = toAlloc;
return S_OK;
}
//
// Append data to the blob
//
HRESULT
AddData(
_In_ PVOID Ptr,
_In_ ULONG Size
)
{
ULONG alignSize = ALIGN_UP_BY( Size, sizeof(ULONG64) );
if( alignSize < Size ) {
return E_OUTOFMEMORY;
}
HRESULT hr = Grow( alignSize );
if( FAILED( hr ) ) {
return hr;
}
memcpy( (PBYTE)blob + blobSize, Ptr, Size );
blobSize += alignSize;
return S_OK;
}
public:
RuleBuilder(
VOID
)
{
blob = NULL;
blobSize = 0;
blobAllocated = 0;
blobVersion = BinaryVersion;
schemaVersion = ConfigurationVersion;
lastEventOffset = 0;
lastFilterOffset = 0;
prevBlobSize = 0;
prevLastEventOffset = UINT_MAX;
prevLastFilterOffset = UINT_MAX;
aggregationOffset = 0;
}
VOID
SetVersion(
_In_ ULONG Version
)
{
schemaVersion = Version;
}
~RuleBuilder(
VOID
)
{
if( blob != NULL ) {
free( blob );
}
}
//
// Get the blob data and size
//
VOID
Detach(
_Out_ PVOID* Rules,
_Out_ PULONG RulesSize
)
{
*Rules = blob;
*RulesSize = blobSize;
blob = NULL;
blobSize = 0;
blobAllocated = 0;
}
//
// Add a base event entry
//
HRESULT
AddEventEntry(
_In_ PRULE_EVENT RuleEvent
)
{
HRESULT hr;
prevBlobSize = blobSize;
//
// Update previous entry
//
if( lastEventOffset != 0 ) {
PRULE_EVENT prev = (PRULE_EVENT) ((PBYTE)blob + lastEventOffset);
prev->NextOffset = blobSize;
} else {
//
// No entry so the blob is not set
//
D_ASSERT( blob == NULL );
RULE_REG_EXT baseRule = {0,};
baseRule.header.Version = blobVersion;
baseRule.RuleRegSize = sizeof(baseRule);
baseRule.SchemaVersion = schemaVersion;
baseRule.FirstEventOffset = sizeof(baseRule);
hr = AddData( &baseRule, sizeof(baseRule) );
if( FAILED( hr ) ) {
return hr;
}
// Now that we have added the header update the offset of the first event to reflect the current location
// We do this because AddData rounds up the location for the next write to be ptr aligned
PRULE_REG_EXT header = (PRULE_REG_EXT)blob;
header->FirstEventOffset = blobSize;
}
prevLastEventOffset = lastEventOffset;
lastEventOffset = blobSize;
hr = AddData( RuleEvent, sizeof(*RuleEvent) );
if( FAILED( hr ) ) {
return hr;
}
//
// Update the rule count
//
PRULE_REG pRule = (PRULE_REG)blob;
pRule->RuleCount++;
prevLastFilterOffset = lastFilterOffset;
lastFilterOffset = 0;
return S_OK;
}
HRESULT UndoEventAdd()
{
if( lastEventOffset == 0 || prevLastEventOffset == ULONG_MAX ) {
// Can't undo more than the very last event (no undo history).
return E_OUTOFMEMORY;
}
PRULE_REG pRule = (PRULE_REG)blob;
pRule->RuleCount--;
lastEventOffset = prevLastEventOffset;
prevLastEventOffset = UINT_MAX;
lastFilterOffset = prevLastFilterOffset;
prevLastFilterOffset = UINT_MAX;
blobSize = prevBlobSize;
if( lastEventOffset == 0 ) {
free( blob );
blob = NULL;
blobSize = 0;
blobAllocated = 0;
}
return S_OK;
}
//
// Add a filter entry for this current event
//
HRESULT
AddFilterEntry(
_In_ PRULE_FILTER RuleFilter
)
{
HRESULT hr;
D_ASSERT( lastEventOffset != 0 );
PRULE_EVENT currentEvent = (PRULE_EVENT)((PBYTE)blob + lastEventOffset);
//
// Update the previous entry
//
if( lastFilterOffset != 0 ) {
PRULE_FILTER prev = (PRULE_FILTER)((PBYTE)blob + lastFilterOffset);
prev->NextOffset = blobSize;
}
lastFilterOffset = blobSize;
// If this is part of an aggregation, set the backpointer to the aggregation object
if (RuleFilter->AggregationId) {
PRULE_AGGREGATION currentAggregation = (PRULE_AGGREGATION)((PBYTE)blob + aggregationOffset);
D_ASSERT(NULL != currentAggregation && currentAggregation->aggregationId == RuleFilter->AggregationId);
// If this is the first entry in the aggregation, update the root node
if (0 == currentAggregation->rootRuleOffset) {
currentAggregation->rootRuleOffset = blobSize;
}
++currentAggregation->ruleCount;
RuleFilter->AggregationOffset = aggregationOffset;
}
// Because we can now include aggregation objects we can no longer assume that the start of the rule chain
// is at a fixed offset from the start so we need to make a note of that too
if (0 == currentEvent->FirstFilterOffset) {
currentEvent->FirstFilterOffset = blobSize;
}
hr = AddData( RuleFilter, sizeof(*RuleFilter) + RuleFilter->DataSize );
// It's possible that this caused a realloc and invalidated the event pointer so recalculate before we dereference it again
currentEvent = (PRULE_EVENT)((PBYTE)blob + lastEventOffset);
if( FAILED( hr ) ) {
return hr;
}
//
// Update the rule event count
//
currentEvent->FilterCount++;
return S_OK;
}
//
// Add a rule aggregation entry
//
HRESULT AddAggregationEntry(_In_ PRULE_AGGREGATION pAggregation)
{
HRESULT hr;
D_ASSERT(lastEventOffset != 0);
// If we already have an aggregation object then set the next pointer to the new one
if (aggregationOffset != 0) {
PRULE_AGGREGATION prev = (PRULE_AGGREGATION)((PBYTE)blob + aggregationOffset);
prev->nextOffset = blobSize;
}
else {
// Record the address of the first record in the header
PRULE_REG_EXT header = (PRULE_REG_EXT)blob;
D_ASSERT(0 == header->FirstAggregationOffset);
header->FirstAggregationOffset = blobSize;
}
// Record the position of the node we are about to add. The rule filters will use this to record
// which aggregation they belong to. It is also used for chaining aggregation nodes.
aggregationOffset = blobSize;
hr = AddData(pAggregation, sizeof(RULE_AGGREGATION));
if (FAILED(hr)) {
return hr;
}
return S_OK;
}
};
//--------------------------------------------------------------------
//
// GetFileContentWithDtd
//
// Fetch the content of the configuration file and add dtd info
//
//--------------------------------------------------------------------
#if defined _WIN64 || defined _WIN32
std::wstring
#elif defined __linux__
std::string
#endif
GetFileContentWithDtd(
_In_ PCTCH FileName,
_In_ ULONG version
)
{
FILE* stream;
#if defined _WIN64 || defined _WIN32
std::wstring ret;
#elif defined __linux__
std::string ret;
#endif
TCHAR Buffer[2048];
PTCHAR dtdContent, startPos, endPos;
BOOLEAN firstRead = TRUE;
#if defined _WIN64 || defined _WIN32
const TCHAR xmlTag[] = _T("<?xml");
const TCHAR endTag[] = _T("?>");
#elif defined __linux__
WCHAR xmlTag[] = {'<', '?', 'x', 'm', 'l', 0};
WCHAR endTag[] = {'?', '>', 0};
#endif
size_t numRead = 0;
if (NULL == FileName) {
return ret;
}
#if defined _WIN64 || defined _WIN32
errno_t err;
err = _tfopen_s(&stream, FileName, _T("r, ccs=UTF-16LE"));
if (err != 0) {
SetLastError(err);
_tprintf(_T("Error: Failed to open configuration file %s: %s\n"), FileName,
GetLastErrorText(Buffer, _countof(Buffer)));
return ret;
}
#elif defined __linux__
stream = fopen(FileName, "rb");
if (stream == NULL) {
printf("Error: Failed to open configuration file %s\n", FileName);
return ret;
}
#endif
//
// Add the dtd rule to identify bad configuration
//
dtdContent = GetDtdFormat(version);
if (dtdContent == NULL) {
fclose( stream );
return ret;
}
#if defined _WIN64 || defined _WIN32
std::wstring dtdAndConfig( dtdContent );
while( (numRead = fread( Buffer, 1, _countof( Buffer ), stream ) / 2) > 0 ) {
#elif defined __linux__
unsigned int len = _tcslen( dtdContent );
//
// dtdAndConfig contains WCHAR data, so is twice the length of dtdContent,
// minus the terminating NULL.
// UTF8toUTF16() writes the NULL, so write it to tmp and then
// copy up to the NULL into dtdAndConfig
//
std::string dtdAndConfig( len * sizeof(WCHAR), 0 );
std::string tmp( ( len + 1) * sizeof(WCHAR), 0 );
if ( 0 == UTF8toUTF16( (PWCHAR)&tmp[0], dtdContent, len + 1 ) ) {
printf("Error: Failed to convert the DTD to UTF-16LE\n");
fclose( stream );
return ret;
}
memcpy( &dtdAndConfig[0], &tmp[0], len * sizeof( WCHAR ) );
while( (numRead = fread( Buffer, 1, sizeof( Buffer ), stream )) > 0 ) {
#endif
//
// Discard <?xml tag if it was added in the front.
//
if (firstRead == TRUE) {
startPos = Buffer;
while ( startPos[0] != '<' && numRead > 0 ) { // skip white space and BOM
startPos++;
numRead--;
}
if ( numRead == 0 ) {
printf( "Error: Too much white space\n" );
fclose( stream );
return ret;
}
firstRead = FALSE;
if (!WCSNICMP( (PWCHAR)startPos, xmlTag, WCSLEN( xmlTag ) - 1 ) ) {
endPos = (PTCHAR) WCSSTR( (PWCHAR)(startPos + WCSLEN( xmlTag ) - 1), endTag );
if ( endPos != NULL ) {
#if defined _WIN64 || defined _WIN32
endPos += WCSLEN( endTag );
#elif defined __linux__
endPos += ( WCSLEN( endTag ) * sizeof( WCHAR ) );
#endif
dtdAndConfig.append( endPos, numRead - (endPos - startPos) );
continue;
}
}
dtdAndConfig.append( startPos, numRead );
continue;
}
dtdAndConfig.append( Buffer, numRead );
}
fclose(stream);
return dtdAndConfig;
}
//--------------------------------------------------------------------
//
// GetFileContentWithDtd8
//
// Fetch the 8-bit content of the configuration file and add dtd info
//
//--------------------------------------------------------------------
std::string
GetFileContentWithDtd8(
_In_ PCCH FileName,
_In_ ULONG version
)
{
FILE* stream;
std::string ret;
CHAR Buffer[2048];
PTCHAR dtdContent;
PCHAR startPos;
PCHAR endPos;
BOOLEAN firstRead = TRUE;
const CHAR xmlTag[] = "<?xml";
const CHAR endTag[] = "?>";
size_t numRead = 0;
if( NULL == FileName ) {
return ret;
}
stream = fopen( FileName, "rb" );
if( stream == NULL ) {
printf( "Error: Failed to open configuration file: %s\n", FileName);
return ret;
}
//
// Add the dtd rule to identify bad configuration
//
dtdContent = GetDtdFormat( version );
if( dtdContent == NULL ) {
fclose( stream );
return ret;
}
#if defined _WIN64 || defined _WIN32
size_t convertedChars = WideCharToMultiByte( CP_UTF8, WC_ERR_INVALID_CHARS, dtdContent, (int)_tcslen( dtdContent ), NULL, 0, NULL, NULL );
std::string dtdAndConfig( convertedChars, 0 );
convertedChars = WideCharToMultiByte( CP_UTF8, WC_ERR_INVALID_CHARS, dtdContent, (int)_tcslen( dtdContent ), &dtdAndConfig[0], (int)convertedChars, NULL, NULL );
#elif defined __linux__
std::string dtdAndConfig( dtdContent );
#endif
while( (numRead = fread( Buffer, 1, sizeof( Buffer ), stream ) ) > 0 ) {
//
// Discard <?xml tag if it was added in the front.
//
if( firstRead == TRUE ) {
startPos = Buffer;
while( startPos[0] != '<' && numRead > 0 ) { // skip white space and BOM
startPos++;
numRead--;
}
if( numRead == 0 ) {
printf( "Error: Too much white space\n" );
fclose( stream );
return ret;
}
firstRead = FALSE;
if( !xmlStrncasecmp( (xmlChar*)startPos, (xmlChar*)xmlTag, (int)strlen( xmlTag ) ) ) {
endPos = strstr( startPos + strlen( xmlTag ), endTag );
if( endPos != NULL ) {
endPos += strlen( endTag );
dtdAndConfig.append( endPos, numRead - (endPos - startPos) );
continue;
}
}
dtdAndConfig.append( startPos, numRead );
continue;
}
dtdAndConfig.append( Buffer, numRead );
}
fclose( stream );
return dtdAndConfig;
}
//--------------------------------------------------------------------
//
// FetchConfigurationVersion
//
// Get the configuration file version
//
//--------------------------------------------------------------------
BOOLEAN
FetchConfigurationVersion(
_In_ PCTCH FileName,
_In_ ULONG* Version,
_Out_ char** XMLEncoding,
_Out_ BOOLEAN* Is16Bit,
_Out_ BOOLEAN* HasBOM
)
{
xmlDoc* doc = NULL;
xmlNode* sysmonNode = NULL;
xmlXPathContextPtr xpathCtx;
xmlChar xmlSysmonQuery[] = "/Sysmon[1]";
xmlXPathObjectPtr xpathObj;
xmlChar* versionString = NULL;
ULONG version = 0;
PCHAR fileEncoding = NULL;
UCHAR sniff[1024];
FILE* sniff_f = NULL;
size_t sniff_read = 0;
CHAR utf16le_str[] = "UTF-16LE";
*XMLEncoding = NULL;
*Is16Bit = false;
*HasBOM = false;
#if defined _WIN64 || defined _WIN32
char fileName[MAX_PATH];
size_t fileNameConv;
fileNameConv = WideCharToMultiByte( CP_UTF8, WC_ERR_INVALID_CHARS, FileName, -1, fileName, sizeof( fileName ), NULL, NULL );
if( fileNameConv == 0 ) {
_tprintf( _T( "Error: Failed to load xml configuration: %s (could not convert to char array)\n" ),
FileName );
return FALSE;
}
fileName[MAX_PATH-1] = 0x00;
#elif defined __linux__
const char* fileName = FileName;
#endif
sniff_f = fopen( fileName, "rb" );
if( !sniff_f ) {
_tprintf( _T( "Error: Failed to open xml configuration: %s "), FileName );
printf( "(%s)\n", strerror( errno ) );
return FALSE;
}
sniff_read = fread( sniff, sizeof(unsigned char), sizeof( sniff ), sniff_f );
if( sniff_read < 2 ) {
_tprintf( _T( "Error: Failed to read xml configuration bytes: %s" ), FileName );
printf( "(%s)\n", strerror( errno ) );
fclose( sniff_f );
return FALSE;
}
fclose( sniff_f );
//
// Configuration files can be encoded in an ASCII-like format (one byte per character)
// or in a 16-bit format (two bytes per character). We need to identify whether the
// file is 8 bit or 16 bit so that later when we attach it to a DTD, we can encode the
// DTD in the same way (if the file is 8 bit, the DTD must be 8 bit; if the file is 16
// bit, the DTD must be 16 bit).
//
// If a Byte Order Mark (BOM) is present (first byte of file isn't white space or the
// '<' character), then we can work out if it specifies a 16 bit encoding (first byte
// is 0xFF) or an 8 bit encoding (any other byte).
//
// If no BOM, then we can work out manually if the file is 8 bit or 16 bit by examining
// the second byte and checking if it is 0x00. The only valid first characters are
// '<' or a whitespace character, all of which will have 0x00 as the second byte if
// the file is 16 bit encoded (as '<', ' ', tab, line feed, carriage return, etc, are
// all in the ASCII range 0x0000 to 0x007F).
//
if( !std::isspace( sniff[0] ) && sniff[0] != '<' ) {
*HasBOM = true;
if( sniff[0] == 0xff ) {
*Is16Bit = true;
}
} else {
if( sniff[1] == 0x00 ) {
fileEncoding = utf16le_str;
*Is16Bit = true;
} else {
*Is16Bit = false;
}
}
//
// read file with detected file encoding if there was no BOM
//
#if defined _WIN64 || defined _WIN32
doc = xmlReadFile( fileName, fileEncoding, 0 );
#elif defined __linux__
doc = xmlReadFile( FileName, fileEncoding, 0 );
#endif
if( !doc ) {
_tprintf( _T( "Error: Failed to load xml configuration: %s (could not read file)\n" ),
FileName );
return FALSE;
}
xpathCtx = xmlXPathNewContext( doc );
if( !xpathCtx ) {
_tprintf( _T( "Error: Failed to find Sysmon tag in configuration: %s\n" ), FileName );
xmlFreeDoc( doc );
return FALSE;
}
xpathObj = xmlXPathEvalExpression( xmlSysmonQuery, xpathCtx );
if( !xpathObj || !xpathObj->nodesetval || xpathObj->nodesetval->nodeNr < 1 ) {
_tprintf( _T( "Error: Failed to find Sysmon tag in configuration: %s\n" ), FileName );
if (xpathObj != NULL) {
xmlXPathFreeObject( xpathObj );
}
xmlXPathFreeContext( xpathCtx );
xmlFreeDoc( doc );
return FALSE;
}
xmlXPathFreeContext( xpathCtx );
sysmonNode = xpathObj->nodesetval->nodeTab[0];
versionString = xmlGetProp( sysmonNode, (xmlChar *)"schemaversion" );
//
// If an <?xml> tag is present and specifies an encoding, then store this to use when reading
// the file with the DTD.
//
if( doc->encoding ) {
*XMLEncoding = _strdup( (PCHAR)doc->encoding );
} else {
*XMLEncoding = NULL;
}
xmlFreeDoc( doc );
xmlXPathFreeObject ( xpathObj );
version = ParseVersionString( (PCHAR)versionString );
if( version == (ULONG)-1 ) {
printf( "Error: Invalid schema version number (%s) ", versionString );
_tprintf( _T(" for configuration: %s\n"), FileName );
xmlFree ( versionString );
return FALSE;
}
*Version = version;
xmlFree ( versionString );
return TRUE;
}
//--------------------------------------------------------------------
//
// GetAdditionalRules
//
// Get additional rules based on configuration.
//
//--------------------------------------------------------------------
BOOLEAN
GetAdditionalRules(
_Out_ PADD_RULES AddRules,
_In_ ULONG MaxSize
)
{
ULONG i;
D_ASSERT( MaxSize > 2 );
i = 0;
ZeroMemory( AddRules, MaxSize * sizeof(*AddRules) );
if( (i + 1) > MaxSize ) {
return FALSE;
}
if( OPT_VALUE(ImageLoad) ) {
AddRules[i].eventType = &SYSMONEVENT_IMAGE_LOAD_Type;
AddRules[i].fieldId = F_IL_Image;
AddRules[i].filterOption = Filter_image;
AddRules[i].dataMultiSz = StringListDup( (PTCHAR)OPT_VALUE(ImageLoad), NULL );
D_ASSERT( AddRules[i].dataMultiSz != NULL && AddRules[i].dataMultiSz[0] != 0 );
i++;
}
if( (i + 1) > MaxSize ) {
return FALSE;
}
if( OPT_VALUE(NetworkConnect) ) {
AddRules[i].eventType = &SYSMONEVENT_NETWORK_CONNECT_Type;
AddRules[i].fieldId = F_NC_Image;
AddRules[i].filterOption = Filter_image;
AddRules[i].dataMultiSz = StringListDup( (PTCHAR)OPT_VALUE(NetworkConnect), NULL );
D_ASSERT( AddRules[i].dataMultiSz != NULL && AddRules[i].dataMultiSz[0] != 0 );
i++;
}
if( (i + 1) > MaxSize ) {
return FALSE;
}
return TRUE;
}
//--------------------------------------------------------------------
//
// FindConfigurationOption
//
// Identify the configuration option matched with the node name
//
//--------------------------------------------------------------------
PCONFIGURATION_OPTION_TYPE
FindConfigurationOption(
_In_ PTCHAR ConfigurationNode
)
{
SIZE_T index;
const TCHAR configName[] = _T("Config");
SIZE_T len;
len = _tcslen( ConfigurationNode );
//
// Handle special configuration options
//
if( len > ARRAYSIZE(configName) &&
!_tcscmp( ConfigurationNode + len - ARRAYSIZE(configName) + 1,
configName ) ) {
len -= ARRAYSIZE(configName) - 1;
}
for( index = 0; index < ConfigOptionTypeCount; index++ ) {
if( ConfigOptionType[index].CommandLineOnly ||
len != ConfigOptionType[index].FieldNameCch ) {
continue;
}
if( !_tcsncmp( ConfigurationNode, ConfigOptionType[index].FieldName, len ) ) {
return &ConfigOptionType[index];
}
}
return NULL;
}
//--------------------------------------------------------------------
//
// GetFieldIndex