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Copy pathdetection_common_bnfasearch.c
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detection_common_bnfasearch.c
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#include <detection/common/detection_com.h>
#include <detection/common/detection_pub.h>
//#include <detection/common/detection_config.h>
//#include <detection/detect/detection_detect_pub.h>
#include <detection/common/detection_mod.h>
#include <detection/common/detection_debug.h>
#include <detection/common/detection_common_mem.h>
#include <detection/common/detection_common_bnfasearch.h>
VOID Detection_Common_BnfaAccumInfo( DETECTION_BNFA_S * pstBnfa );
VOID Detection_Common_BnfaInitSummary( VOID );
/*
* Used to initialize last ulState, states are limited to 0-16M
* so this will not conflict.
*/
#define DETECTION_COMMON_LAST_STATE_INIT 0xffffffff
/*
* Case Translation Table - his guarantees we use
* indexed lookups for case conversion
*/
static UCHAR g_ucXlatcase[DETECTION_COMMON_BNFA_MAX_ALPHABET_SIZE];
static VOID Detection_Common_InitXlatcase(VOID)
{
ULONG i;
static ULONG ulFirst=1;
if( ulFirst ==0)
return;
for(i=0; i<DETECTION_COMMON_BNFA_MAX_ALPHABET_SIZE; i++)
{
g_ucXlatcase[i] = (UCHAR)ToUpper(i);
}
ulFirst=0;
}
/*
* Custom memory allocator
*/
static
VOID * Detection_Common_Bnfa_Alloc( ULONG ulN, ULONG * pulM )
{
VOID * pvP = (ULONG*)Detection_GlobalMalloc(ulN, DETECTION_MEM_TAG);
if( pvP )
{
if(pulM)
{
pulM[0] += ulN;
}
}
return pvP;
}
static
VOID Detection_Common_Bnfa_Free( VOID *pvP, ULONG ulN, ULONG * pulM )
{
if( pvP )
{
Detection_GlobalFree(pvP);
if(pulM)
{
pulM[0] -= ulN;
}
}
}
#define DETECTION_COMMON_BNFA_MALLOC(ulN,memory) Detection_Common_Bnfa_Alloc(ulN,&(memory))
#define DETECTION_COMMON_BNFA_FREE(pvP,ulN,memory) Detection_Common_Bnfa_Free(pvP,ulN,&(memory))
/* queue memory traker */
static ULONG g_ulQueueMemory=0;
/*
* simple queue node
*/
typedef struct stQnode
{
ULONG ulState;
struct stQnode *pstNext;
}
DETECTION_QNODE_S;
/*
* simple fifo queue structure
*/
typedef struct stQueue
{
DETECTION_QNODE_S * pstHead, *pstTail;
ULONG ulCount;
ULONG ulMaxcnt;
}
DETECTION_QUEUE_S;
/*
* Initialize the fifo queue
*/
static
VOID Detection_Common_QueueInit (DETECTION_QUEUE_S * pstQueue)
{
pstQueue->pstHead = pstQueue->pstTail = 0;
pstQueue->ulCount= 0;
pstQueue->ulMaxcnt=0;
}
/*
* Add items to pstTail of queue (fifo)
*/
static
ULONG Detection_Common_QueueAdd (DETECTION_QUEUE_S * pstQueue, ULONG ulState)
{
DETECTION_QNODE_S * pstQnode= NULL;
if (pstQueue->pstHead==NULL)
{
pstQnode = pstQueue->pstTail = pstQueue->pstHead = (DETECTION_QNODE_S *) DETECTION_COMMON_BNFA_MALLOC (sizeof(DETECTION_QNODE_S),g_ulQueueMemory);
if(!pstQnode) return 1;
pstQnode->ulState = ulState;
pstQnode->pstNext = 0;
}
else
{
pstQnode = (DETECTION_QNODE_S *) DETECTION_COMMON_BNFA_MALLOC (sizeof(DETECTION_QNODE_S),g_ulQueueMemory);
pstQnode->ulState = ulState;
pstQnode->pstNext = 0;
pstQueue->pstTail->pstNext = pstQnode;
pstQueue->pstTail = pstQnode;
}
pstQueue->ulCount++;
if( pstQueue->ulCount > pstQueue->ulMaxcnt )
pstQueue->ulMaxcnt = pstQueue->ulCount;
return 0;
}
/*
* Remove items from pstHead of queue (fifo)
*/
static
ULONG Detection_Common_QueueRemove (DETECTION_QUEUE_S * pstQueue)
{
ULONG ulState = 0;
DETECTION_QNODE_S * pstQnode= NULL;
if (pstQueue->pstHead)
{
pstQnode = pstQueue->pstHead;
ulState = pstQnode->ulState;
pstQueue->pstHead = pstQueue->pstHead->pstNext;
pstQueue->ulCount--;
if( pstQueue->pstHead==NULL )
{
pstQueue->pstTail = 0;
pstQueue->ulCount = 0;
}
DETECTION_COMMON_BNFA_FREE (pstQnode,sizeof(DETECTION_QNODE_S),g_ulQueueMemory);
}
return ulState;
}
/*
* Return ulCount of items in the queue
*/
static
ULONG Detection_Common_QueueCount (DETECTION_QUEUE_S * pstQueue)
{
return pstQueue->ulCount;
}
/*
* Free the queue
*/
static
VOID Detection_Common_QueueFree (DETECTION_QUEUE_S * pstQueue)
{
while (Detection_Common_QueueCount (pstQueue))
{
Detection_Common_QueueRemove (pstQueue);
}
}
/*
* Get pstNext ulState from transition list
*/
static
ULONG Detection_Common_BnfaListGetNextState( DETECTION_BNFA_S * pstBnfa, ULONG ulState, ULONG ulInput )
{
if ( ulState == 0 ) /* Full set of states always */
{
ulBnfaState * pulBnfaState = (ulBnfaState*)pstBnfa->ppstBnfaTransTable[0];
if(pulBnfaState==NULL)
{
return 0;
}
return pulBnfaState[ulInput];
}
else
{
DETECTION_BNFA_TRANSNODE_S * pstBnfaTransNode = pstBnfa->ppstBnfaTransTable[ulState];
while( pstBnfaTransNode )
{
if( pstBnfaTransNode->ulKey == (ULONG)ulInput )
{
return pstBnfaTransNode->ulNextState;
}
pstBnfaTransNode=pstBnfaTransNode->pstNext;
}
return DETECTION_COMMON_BNFA_FAIL_STATE; /* Fail ulState */
}
}
/*
* Put pstNext ulState - pstHead insertion, and transition updates
*/
static
ULONG Detection_Common_BnfaListPutNextState( DETECTION_BNFA_S * pstBnfa, ULONG ulState, ULONG ulInput, ULONG ulNextState )
{
if( ulState >= pstBnfa->ulBnfaMaxStates )
{
return 1;
}
if( ulInput >= pstBnfa->ulBnfaAlphabetSize )
{
return 1;
}
if( ulState == 0 )
{
ulBnfaState * pulBnfaState;
pulBnfaState = (ulBnfaState*)pstBnfa->ppstBnfaTransTable[0];
if( pulBnfaState==NULL )
{
pulBnfaState = (ulBnfaState*)DETECTION_COMMON_BNFA_MALLOC(sizeof(ulBnfaState)*pstBnfa->ulBnfaAlphabetSize,pstBnfa->ulListMemory);
if( pulBnfaState ==NULL)
{
return 1;
}
pstBnfa->ppstBnfaTransTable[0] = (DETECTION_BNFA_TRANSNODE_S*)pulBnfaState;
}
if( pulBnfaState[ulInput] )
{
pulBnfaState[ulInput] = ulNextState;
return 0;
}
pulBnfaState[ulInput] = ulNextState;
}
else
{
DETECTION_BNFA_TRANSNODE_S * pstBnfaTransNode;
DETECTION_BNFA_TRANSNODE_S * pstTnew;
/* Check if the transition already exists, if so just update the ulNextState */
pstBnfaTransNode = pstBnfa->ppstBnfaTransTable[ulState];
while( pstBnfaTransNode )
{
if( pstBnfaTransNode->ulKey == (ULONG)ulInput ) /* transition already exists- reset the pstNext ulState */
{
pstBnfaTransNode->ulNextState = ulNextState;
return 0;
}
pstBnfaTransNode=pstBnfaTransNode->pstNext;
}
/* Definitely not an existing transition - add it */
pstTnew = (DETECTION_BNFA_TRANSNODE_S*)DETECTION_COMMON_BNFA_MALLOC(sizeof(DETECTION_BNFA_TRANSNODE_S),pstBnfa->ulListMemory);
if( pstTnew ==NULL)
{
return 1;
}
pstTnew->ulKey = ulInput;
pstTnew->ulNextState = ulNextState;
pstTnew->pstNext = pstBnfa->ppstBnfaTransTable[ulState];
pstBnfa->ppstBnfaTransTable[ulState] = pstTnew;
}
pstBnfa->ulBnfaNumTrans++;
return 0;
}
/*
* Free the entire transition list table
*/
static
ULONG Detection_Common_BnfaListFreeTable( DETECTION_BNFA_S * pstBnfa )
{
ULONG i;
DETECTION_BNFA_TRANSNODE_S * pstBnfaTransNode= NULL, *pstP= NULL;
if( pstBnfa->ppstBnfaTransTable ==NULL) return 0;
if( pstBnfa->ppstBnfaTransTable[0] )
{
DETECTION_COMMON_BNFA_FREE(pstBnfa->ppstBnfaTransTable[0],sizeof(ulBnfaState)*pstBnfa->ulBnfaAlphabetSize,pstBnfa->ulListMemory);
}
for(i=1; i<pstBnfa->ulBnfaMaxStates; i++)
{
pstBnfaTransNode = pstBnfa->ppstBnfaTransTable[i];
while( pstBnfaTransNode )
{
pstP = pstBnfaTransNode;
pstBnfaTransNode = pstBnfaTransNode->pstNext;
DETECTION_COMMON_BNFA_FREE(pstP,sizeof(DETECTION_BNFA_TRANSNODE_S),pstBnfa->ulListMemory);
}
}
if( pstBnfa->ppstBnfaTransTable )
{
DETECTION_COMMON_BNFA_FREE(pstBnfa->ppstBnfaTransTable,sizeof(DETECTION_BNFA_TRANSNODE_S*)*pstBnfa->ulBnfaMaxStates,pstBnfa->ulListMemory);
pstBnfa->ppstBnfaTransTable = 0;
}
return 0;
}
/*
* Converts a single row of states from list format to a full format
*/
static
ULONG Detection_Common_BnfaListConvRowToFull(DETECTION_BNFA_S * pstBnfa, ulBnfaState ulState, ulBnfaState * pulFull )
{
if( (ULONG)ulState >= pstBnfa->ulBnfaMaxStates ) /* protects 'full' against overflow */
{
return 1;
}
if( ulState == 0 )
{
if( pstBnfa->ppstBnfaTransTable[0] )
MemCpy(pulFull,pstBnfa->ppstBnfaTransTable[0],sizeof(ulBnfaState)*pstBnfa->ulBnfaAlphabetSize);
else
MemSet(pulFull,0,sizeof(ulBnfaState)*pstBnfa->ulBnfaAlphabetSize);
return pstBnfa->ulBnfaAlphabetSize;
}
else
{
ULONG ulTcnt = 0;
DETECTION_BNFA_TRANSNODE_S * pstBnfaTransNode = pstBnfa->ppstBnfaTransTable[ ulState ];
MemSet(pulFull,0,sizeof(ulBnfaState)*pstBnfa->ulBnfaAlphabetSize);
if( pstBnfaTransNode ==NULL)
{
return 0;
}
while(pstBnfaTransNode && (pstBnfaTransNode->ulKey < DETECTION_COMMON_BNFA_MAX_ALPHABET_SIZE ) )
{
pulFull[ pstBnfaTransNode->ulKey ] = pstBnfaTransNode->ulNextState;
ulTcnt++;
pstBnfaTransNode = pstBnfaTransNode->pstNext;
}
return ulTcnt;
}
}
/*
* Add pucPattern characters to the initial upper case trie
* unless Exact has been specified, in which case all patterns
* are assumed to be case specific.
*/
static
ULONG Detection_Common_BnfaAddPatternStates (DETECTION_BNFA_S * pstBnfa, DETECTION_BNFAPATTERN_S * pstBnfaPattern)
{
ULONG ulState= 0, ulNext= 0, ulN= 0;
UCHAR * pucPattern= NULL;
DETECTION_BNFA_MATCHNODE_S * pstPmn= NULL;
ulN = pstBnfaPattern->ulPatternLen;
pucPattern = pstBnfaPattern->pucCasepatrn;
ulState = 0;
/*
* Match up pucPattern with existing states
*/
for (; ulN > 0; pucPattern++, ulN--)
{
if( pstBnfa->ulBnfaCaseMode == DETECTION_COMMON_BNFA_CASE )
ulNext = Detection_Common_BnfaListGetNextState(pstBnfa,ulState,*pucPattern);
else
ulNext = Detection_Common_BnfaListGetNextState(pstBnfa,ulState,g_ucXlatcase[*pucPattern]);
if( ulNext == DETECTION_COMMON_BNFA_FAIL_STATE || ulNext == 0 )
{
break;
}
ulState = ulNext;
}
/*
* Add new states for the rest of the pucPattern bytes, 1 ulState per byte, uppercase
*/
for (; ulN > 0; pucPattern++, ulN--)
{
pstBnfa->ulBnfaNumStates++;
if( pstBnfa->ulBnfaCaseMode == DETECTION_COMMON_BNFA_CASE )
{
if( Detection_Common_BnfaListPutNextState(pstBnfa,ulState,*pucPattern,pstBnfa->ulBnfaNumStates) >0 )
return 1;
}
else
{
if( Detection_Common_BnfaListPutNextState(pstBnfa,ulState,g_ucXlatcase[*pucPattern],pstBnfa->ulBnfaNumStates) >0 )
return 1;
}
ulState = pstBnfa->ulBnfaNumStates;
if ( pstBnfa->ulBnfaNumStates >= pstBnfa->ulBnfaMaxStates )
{
return 1;
}
}
/* Add a pattern to the list of patterns terminated at this ulState */
pstPmn = (DETECTION_BNFA_MATCHNODE_S*)DETECTION_COMMON_BNFA_MALLOC(sizeof(DETECTION_BNFA_MATCHNODE_S),pstBnfa->ulMatchlistMemory);
if( pstPmn==NULL )
{
return 1;
}
pstPmn->pvData = pstBnfaPattern;
pstPmn->pstNext = pstBnfa->ppstBnfaMatchList[ulState];
pstBnfa->ppstBnfaMatchList[ulState] = pstPmn;
return 0;
}
static /* used only by Detection_Common_KcontainsJ() */
ULONG
Detection_Common_BnfaConvNodeToFull(DETECTION_BNFA_TRANSNODE_S *pstBnfaTransNode, ulBnfaState * pulFull )
{
ULONG ulTcnt = 0;
MemSet(pulFull,0,sizeof(ulBnfaState)*DETECTION_COMMON_BNFA_MAX_ALPHABET_SIZE);
if( pstBnfaTransNode==NULL )
{
return 0;
}
while(pstBnfaTransNode && (pstBnfaTransNode->ulKey < DETECTION_COMMON_BNFA_MAX_ALPHABET_SIZE ) )
{
pulFull[ pstBnfaTransNode->ulKey ] = pstBnfaTransNode->ulNextState;
ulTcnt++;
pstBnfaTransNode = pstBnfaTransNode->pstNext;
}
return ulTcnt;
}
/*
* containment test -
* test if all of tj transitions are in tk
*/
static
ULONG Detection_Common_KcontainsJ(DETECTION_BNFA_TRANSNODE_S * pstTk, DETECTION_BNFA_TRANSNODE_S *pstTj )
{
ulBnfaState ulFull[DETECTION_COMMON_BNFA_MAX_ALPHABET_SIZE];
if( Detection_Common_BnfaConvNodeToFull(pstTk,ulFull) ==0 )
return 1; /* emtpy ulState */
while( pstTj )
{
if( ulFull[pstTj->ulKey]==0 )
return 0;
pstTj=pstTj->pstNext; /* get pstNext tj ulKey */
}
return 1;
}
/*
* 1st optimization - eliminate duplicate fail states
*
* check if a fail ulState is a subset of the current ulState,
* if so recurse to the pstNext fail ulState, and so on.
*/
static
ULONG Detection_Common_BnfaOptNfa (DETECTION_BNFA_S * pstBnfa)
{
ULONG ulCnt=0;
ULONG ulK, ulFs, ulFr;
ulBnfaState * pstFailState = pstBnfa->ppulBnfaFailState;
for(ulK=2;ulK<pstBnfa->ulBnfaNumStates;ulK++)
{
ulFr = ulFs = pstFailState[ulK];
while( ulFs && Detection_Common_KcontainsJ(pstBnfa->ppstBnfaTransTable[ulK],pstBnfa->ppstBnfaTransTable[ulFs]) )
{
ulFs = pstFailState[ulFs];
}
if( ulFr != ulFs )
{
ulCnt++;
pstFailState[ ulK ] = ulFs;
}
}
if( ulCnt)DETECTION_PARSER_DEBUG(DETECTION_DEBUGTYPE_PROCESS,"ac-pstBnfa: %lu nfa optimizations found in %lu states\n",ulCnt,pstBnfa->ulBnfaNumStates);
return 0;
}
/*
* Build a non-deterministic finite automata using Aho-Corasick construction
* The keyword trie must already be built via Detection_Common_BnfaAddPatternStates()
*/
static
ULONG Detection_Common_BnfaBuildNfa (DETECTION_BNFA_S * pstBnfa)
{
ULONG ulR, ulS, i;
DETECTION_QUEUE_S stQnode, *pstQueue = &stQnode;
ulBnfaState * pstFailState = pstBnfa->ppulBnfaFailState;
DETECTION_BNFA_MATCHNODE_S ** ppstMatchList = pstBnfa->ppstBnfaMatchList;
DETECTION_BNFA_MATCHNODE_S * pstMlist= NULL;
DETECTION_BNFA_MATCHNODE_S * pstPx= NULL;
/* Init a Queue */
Detection_Common_QueueInit (pstQueue);
/* Add the ulState 0 transitions 1st,
* the states at depth 1, fail to ulState 0
*/
for (i = 0; i < pstBnfa->ulBnfaAlphabetSize; i++)
{
/* note that ulState zero deos not fail,
* it just returns 0..nstates-1
*/
ulS = Detection_Common_BnfaListGetNextState(pstBnfa,0,i);
if( ulS ) /* don'pstBnfaTransNode bother adding ulState zero */
{
if( Detection_Common_QueueAdd (pstQueue, ulS) )
{
return 1;
}
pstFailState[ulS] = 0;
}
}
/* Build the fail ulState successive layer of transitions */
while (Detection_Common_QueueCount (pstQueue) > 0)
{
ulR = Detection_Common_QueueRemove (pstQueue);
/* Find Final States for any Failure */
for(i = 0; i<pstBnfa->ulBnfaAlphabetSize; i++)
{
ULONG ulFs, pstNext;
ulS = Detection_Common_BnfaListGetNextState(pstBnfa,ulR,i);
if( ulS == DETECTION_COMMON_BNFA_FAIL_STATE )
continue;
if( Detection_Common_QueueAdd (pstQueue, ulS) )
{
return 1;
}
ulFs = pstFailState[ulR];
/*
* Locate the pstNext valid ulState for 'i' starting at ulFs
*/
while( (pstNext=Detection_Common_BnfaListGetNextState(pstBnfa,ulFs,i)) == DETECTION_COMMON_BNFA_FAIL_STATE )
{
ulFs = pstFailState[ulFs];
}
/*
* Update 's' ulState failure ulState to point to the pstNext valid ulState
*/
pstFailState[ulS] = pstNext;
/*
* Copy 'pstNext'states ppstMatchList into 's' states ppstMatchList,
* we just create a new list nodes, the patterns are not copied.
*/
for( pstMlist = ppstMatchList[pstNext];pstMlist;pstMlist = pstMlist->pstNext)
{
/* Dup the node, don't copy the data */
pstPx = (DETECTION_BNFA_MATCHNODE_S*)DETECTION_COMMON_BNFA_MALLOC(sizeof(DETECTION_BNFA_MATCHNODE_S),pstBnfa->ulMatchlistMemory);
if( !pstPx )
{
return 0;
}
pstPx->pvData = pstMlist->pvData;
pstPx->pstNext = ppstMatchList[ulS]; /* insert at pstHead */
ppstMatchList[ulS] = pstPx;
}
}
}
/* Clean up the queue */
Detection_Common_QueueFree (pstQueue);
/* optimize the failure states */
if( pstBnfa->ulBnfaOpt )
Detection_Common_BnfaOptNfa(pstBnfa);
return 0;
}
/*
* Convert ulState machine to csparse format
*
* Merges ulState/transition/failure arrays into one.
*
* For each ulState we use a ulState-word followed by the transition list for
* the ulState sw(ulState 0 )...tl(ulState 0) sw(ulState 1)...tl(state1) sw(state2)...
* tl(state2) ....
*
* The transition and failure states are replaced with the start index of
* transition ulState, this eliminates the NextState[] lookup....
*
* The compaction of multiple arays into a single array reduces the total
* number of states that can be handled since the max index is 2^24-1,
* whereas without compaction we had 2^24-1 states.
*/
ulBnfaState ulFull[DETECTION_COMMON_BNFA_MAX_ALPHABET_SIZE]={0};
static
ULONG Detection_Common_BnfaConvListToCsparseArray(DETECTION_BNFA_S * pstBnfa)
{
ULONG ulM=0, ulK, i, ulNc=0;
ulBnfaState ulState=0;
ulBnfaState * pstFailState = (ulBnfaState *)pstBnfa->ppulBnfaFailState;
ulBnfaState * pstPs= NULL; /* transition list */
ulBnfaState * pstPi= NULL; /* ulState indexes into pstPs */
ulBnfaState ulPsIndex=0;
ULONG ulNps=0;
/*ulBnfaState ulFull[DETECTION_COMMON_BNFA_MAX_ALPHABET_SIZE]={0};*/
memset( ulFull, 0x00, sizeof(ulBnfaState) * DETECTION_COMMON_BNFA_MAX_ALPHABET_SIZE );
/* ulCount total ulState transitions, account for ulState and control words */
ulNps = 0;
for(ulK=0;ulK<pstBnfa->ulBnfaNumStates;ulK++)
{
ulNps++; /* ulState word */
ulNps++; /* control word */
/* ulCount transitions */
ulNc = 0;
Detection_Common_BnfaListConvRowToFull(pstBnfa, (ulBnfaState)ulK, ulFull );
for( i=0; i<pstBnfa->ulBnfaAlphabetSize; i++ )
{
ulState = ulFull[i] & DETECTION_COMMON_BNFA_SPARSE_MAX_STATE;
if( ulState != 0 )
{
ulNc++;
}
}
/* add in transition ulCount */
if( (ulK == 0 && pstBnfa->ulBnfaForceFullZeroState) || ulNc > DETECTION_COMMON_BNFA_SPARSE_MAX_ROW_TRANSITIONS )
{
ulNps += DETECTION_COMMON_BNFA_MAX_ALPHABET_SIZE;
}
else
{
for( i=0; i<pstBnfa->ulBnfaAlphabetSize; i++ )
{
ulState = ulFull[i] & DETECTION_COMMON_BNFA_SPARSE_MAX_STATE;
if( ulState != 0 )
{
ulNps++;
}
}
}
}
/* check if we have too many states + transitions */
if( ulNps > DETECTION_COMMON_BNFA_SPARSE_MAX_STATE )
{
/* Fatal */
return 1;
}
/*
Alloc The Transition List - we need an array of ulBnfaState items of size 'ulNps'
*/
pstPs = DETECTION_COMMON_BNFA_MALLOC( ulNps*sizeof(ulBnfaState),pstBnfa->ulNextstateMemory);
if( pstPs ==NULL)
{
/* Fatal */
return 1;
}
pstBnfa->ppulBnfaTransList = pstPs;
/*
State Index list for pstPi - we need an array of ulBnfaState items of size 'NumStates'
*/
pstPi = DETECTION_COMMON_BNFA_MALLOC( pstBnfa->ulBnfaNumStates*sizeof(ulBnfaState),pstBnfa->ulNextstateMemory);
if( pstPi ==NULL)
{
/* Fatal */
return 1;
}
/*
Build the Transition List Array
*/
for(ulK=0;ulK<pstBnfa->ulBnfaNumStates;ulK++)
{
pstPi[ulK] = ulPsIndex; /* save index of start of ulState 'ulK' */
pstPs[ ulPsIndex ] = ulK; /* save the ulState were in as the 1st word */
ulPsIndex++; /* skip past ulState word */
/* conver ulState 'ulK' to full format */
Detection_Common_BnfaListConvRowToFull(pstBnfa, (ulBnfaState)ulK, ulFull );
/* ulCount transitions */
ulNc = 0;
for( i=0; i<pstBnfa->ulBnfaAlphabetSize; i++ )
{
ulState = ulFull[i] & DETECTION_COMMON_BNFA_SPARSE_MAX_STATE;
if( ulState != 0 )
{
ulNc++;
}
}
/* add a ulFull ulState or a sparse ulState */
if( (ulK == 0 && pstBnfa->ulBnfaForceFullZeroState) ||
ulNc > DETECTION_COMMON_BNFA_SPARSE_MAX_ROW_TRANSITIONS )
{
/* set the control word */
pstPs[ulPsIndex] = DETECTION_COMMON_BNFA_SPARSE_FULL_BIT;
pstPs[ulPsIndex] |= pstFailState[ulK] & DETECTION_COMMON_BNFA_SPARSE_MAX_STATE;
if( pstBnfa->ppstBnfaMatchList[ulK] )
{
pstPs[ulPsIndex] |= DETECTION_COMMON_BNFA_SPARSE_MATCH_BIT;
}
ulPsIndex++;
/* copy the transitions */
Detection_Common_BnfaListConvRowToFull(pstBnfa, (ulBnfaState)ulK, &pstPs[ulPsIndex] );
ulPsIndex += DETECTION_COMMON_BNFA_MAX_ALPHABET_SIZE; /* add in 256 transitions */
}
else
{
/* set the control word */
pstPs[ulPsIndex] = ulNc<<DETECTION_COMMON_BNFA_SPARSE_COUNT_SHIFT ;
pstPs[ulPsIndex] |= pstFailState[ulK]&DETECTION_COMMON_BNFA_SPARSE_MAX_STATE;
if( pstBnfa->ppstBnfaMatchList[ulK] )
{
pstPs[ulPsIndex] |= DETECTION_COMMON_BNFA_SPARSE_MATCH_BIT;
}
ulPsIndex++;
/* add in the transitions */
for( ulM=0, i=0; i<pstBnfa->ulBnfaAlphabetSize && ulM<ulNc; i++ )
{
ulState = ulFull[i] & DETECTION_COMMON_BNFA_SPARSE_MAX_STATE;
if( ulState != 0 )
{
pstPs[ulPsIndex++] = (i<<DETECTION_COMMON_BNFA_SPARSE_VALUE_SHIFT) | ulState;
ulM++;
}
}
}
}
/* sanity check we have not overflowed our buffer */
if( ulPsIndex > ulNps )
{
/* Fatal */
return 1;
}
/*
Replace Transition states with Transition Indices.
This allows us to skip using NextState[] to locate the pstNext ulState
This limits us to <16M transitions due to 24 bit ulState sizes, and the fact
we have now converted pstNext-ulState fields to pstNext-index fields in this array,
and we have merged the pstNext-ulState and ulState arrays.
*/
ulPsIndex=0;
for(ulK=0; ulK< pstBnfa->ulBnfaNumStates; ulK++ )
{
if( pstPi[ulK] >= ulNps )
{
/* Fatal */
return 1;
}
//ulPsIndex = pstPi[ulK]; /* get index of pstNext ulState */
ulPsIndex++; /* skip ulState id */
/* Full Format */
if( pstPs[ulPsIndex] & DETECTION_COMMON_BNFA_SPARSE_FULL_BIT )
{
/* Do the fail-ulState */
pstPs[ulPsIndex] = ( pstPs[ulPsIndex] & 0xff000000 ) |
( pstPi[ pstPs[ulPsIndex] & DETECTION_COMMON_BNFA_SPARSE_MAX_STATE ] ) ;
ulPsIndex++;
/* Do the transition-states */
for(i=0;i<DETECTION_COMMON_BNFA_MAX_ALPHABET_SIZE;i++)
{
pstPs[ulPsIndex] = ( pstPs[ulPsIndex] & 0xff000000 ) |
( pstPi[ pstPs[ulPsIndex] & DETECTION_COMMON_BNFA_SPARSE_MAX_STATE ] ) ;
ulPsIndex++;
}
}
/* Sparse Format */
else
{
ulNc = (pstPs[ulPsIndex] & DETECTION_COMMON_BNFA_SPARSE_COUNT_BITS)>>DETECTION_COMMON_BNFA_SPARSE_COUNT_SHIFT;
/* Do the cw = [cb | fail-ulState] */
pstPs[ulPsIndex] = ( pstPs[ulPsIndex] & 0xff000000 ) |
( pstPi[ pstPs[ulPsIndex] & DETECTION_COMMON_BNFA_SPARSE_MAX_STATE ] );
ulPsIndex++;
/* Do the transition-states */
for(i=0;i<ulNc;i++)
{
pstPs[ulPsIndex] = ( pstPs[ulPsIndex] & 0xff000000 ) |
( pstPi[ pstPs[ulPsIndex] & DETECTION_COMMON_BNFA_SPARSE_MAX_STATE ] );
ulPsIndex++;
}
}
/* check for buffer overflow again */
if( ulPsIndex > ulNps )
{
/* Fatal */
return 1;
}
}
DETECTION_COMMON_BNFA_FREE(pstPi,pstBnfa->ulBnfaNumStates*sizeof(ulBnfaState),pstBnfa->ulNextstateMemory);
return 0;
}
DETECTION_BNFA_S * Detection_Common_BnfaNew(VOID (*pvFuncUserFree)(VOID *p))
{
DETECTION_BNFA_S * pstBnfa= NULL;
static ULONG ulFirst=1;
ULONG ulBnfaMemory=0;
if( ulFirst )
{
Detection_Common_BnfaInitSummary();
ulFirst=0;
}
Detection_Common_InitXlatcase ();
pstBnfa = (DETECTION_BNFA_S *) DETECTION_COMMON_BNFA_MALLOC(sizeof(DETECTION_BNFA_S),ulBnfaMemory);
if(pstBnfa==NULL)
return 0;
if( pstBnfa )
{
pstBnfa->ulBnfaOpt = 0;
pstBnfa->ulBnfaCaseMode = DETECTION_COMMON_BNFA_PER_PAT_CASE;
pstBnfa->ulBnfaFormat = DETECTION_COMMON_BNFA_SPARSE;
pstBnfa->ulBnfaAlphabetSize = DETECTION_COMMON_BNFA_MAX_ALPHABET_SIZE;
pstBnfa->ulBnfaForceFullZeroState = 1;
pstBnfa->ulBnfaMemory = sizeof(DETECTION_BNFA_S);
pstBnfa->pvFuncUserfree = pvFuncUserFree;
}
g_ulQueueMemory = 0;
return pstBnfa;
}
VOID Detection_Common_BnfaSetOpt(DETECTION_BNFA_S * pstP, ULONG ulFlag)
{
pstP->ulBnfaOpt=ulFlag;
}
/*
* Fee all memory
*/
VOID Detection_Common_BnfaFree (DETECTION_BNFA_S * pstBnfa)
{
ULONG i;
DETECTION_BNFAPATTERN_S * pstPatrn= NULL, *pstIpatrn= NULL;
DETECTION_BNFA_MATCHNODE_S * pstMlist= NULL, *pstIlist= NULL;
for(i = 0; i < pstBnfa->ulBnfaNumStates; i++)
{
/* free match list entries */
pstMlist = pstBnfa->ppstBnfaMatchList[i];
while (pstMlist)
{
pstIlist = pstMlist;
pstMlist = pstMlist->pstNext;
DETECTION_COMMON_BNFA_FREE(pstIlist,sizeof(DETECTION_BNFA_MATCHNODE_S),pstBnfa->ulMatchlistMemory);
}
pstBnfa->ppstBnfaMatchList[i] = 0;
#ifdef ALLOW_NFA_FULL
/* free pstNext ulState entries */
if( pstBnfa->ulBnfaFormat==DETECTION_COMMON_BNFA_FULL )/* Full format */
{
if( pstBnfa->ppulBnfaNextState[i] )
{
DETECTION_COMMON_BNFA_FREE(pstBnfa->ppulBnfaNextState[i],pstBnfa->ulBnfaAlphabetSize*sizeof(ulBnfaState),pstBnfa->ulNextstateMemory);
}
}
#endif
}
/* Free patterns */
pstPatrn = pstBnfa->pstBnfaPatterns;
while(pstPatrn)
{
pstIpatrn=pstPatrn;
pstPatrn=pstPatrn->pstNext;
DETECTION_COMMON_BNFA_FREE(pstIpatrn->pucCasepatrn,pstIpatrn->ulPatternLen,pstBnfa->ulPatMemory);
if(pstBnfa->pvFuncUserfree && pstIpatrn->pvUserdata)
pstBnfa->pvFuncUserfree(pstIpatrn->pvUserdata);
DETECTION_COMMON_BNFA_FREE(pstIpatrn,sizeof(DETECTION_BNFAPATTERN_S),pstBnfa->ulPatMemory);
}
/* Free arrays */
DETECTION_COMMON_BNFA_FREE(pstBnfa->ppulBnfaFailState,pstBnfa->ulBnfaNumStates*sizeof(ulBnfaState),pstBnfa->ulFailstateMemory);
DETECTION_COMMON_BNFA_FREE(pstBnfa->ppstBnfaMatchList,pstBnfa->ulBnfaNumStates*sizeof(DETECTION_BNFAPATTERN_S*),pstBnfa->ulMatchlistMemory);
DETECTION_COMMON_BNFA_FREE(pstBnfa->ppulBnfaNextState,pstBnfa->ulBnfaNumStates*sizeof(ulBnfaState*),pstBnfa->ulNextstateMemory);
DETECTION_COMMON_BNFA_FREE(pstBnfa->ppulBnfaTransList,(2*pstBnfa->ulBnfaNumStates+pstBnfa->ulBnfaNumTrans)*sizeof(ulBnfaState*),pstBnfa->ulNextstateMemory);
Detection_GlobalFree( pstBnfa ); /* cannot update memory tracker when deleting pstBnfa so just 'Detection_Common_GlobalFree' it !*/
}
/*
* Add a pattern to the pattern list
*/
ULONG Detection_Common_BnfaAddPattern (DETECTION_BNFA_S * pstBnfa,
UCHAR *pucPat,
ULONG ulN,
ULONG ulNocase,
VOID * pvUserdata )
{
DETECTION_BNFAPATTERN_S * pstList= NULL;
pstList = (DETECTION_BNFAPATTERN_S *)DETECTION_COMMON_BNFA_MALLOC(sizeof(DETECTION_BNFAPATTERN_S),pstBnfa->ulPatMemory);
if(pstList==NULL) return 1;
pstList->pucCasepatrn = (UCHAR *)DETECTION_COMMON_BNFA_MALLOC(ulN,pstBnfa->ulPatMemory );
if(pstList->pucCasepatrn==NULL) return 1;
MemCpy (pstList->pucCasepatrn, pucPat, ulN);
pstList->ulPatternLen = ulN;
pstList->ulNocase = ulNocase;
pstList->pvUserdata = pvUserdata;
pstList->pstNext = pstBnfa->pstBnfaPatterns; /* insert at front of list */
pstBnfa->pstBnfaPatterns = pstList;
pstBnfa->ulBnfaPatternCnt++;
return 0;
}
/*
* Compile the patterns into an nfa ulState machine
*/
ULONG Detection_Common_BnfaCompile (DETECTION_BNFA_S * pstBnfa)
{
DETECTION_BNFAPATTERN_S * pstList;
DETECTION_BNFA_MATCHNODE_S ** ppstTmpMatchList;
ULONG ulCntMatchStates;
ULONG i;
static ULONG ulFirst=1;
if( ulFirst )
{
Detection_Common_BnfaInitSummary();
ulFirst=0;
}
g_ulQueueMemory =0;
/* Count number of states */
for(pstList = pstBnfa->pstBnfaPatterns; pstList != NULL; pstList = pstList->pstNext)
{
pstBnfa->ulBnfaMaxStates += pstList->ulPatternLen;
}