/* $Id$ *//* * sp_preprocopt.c * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License Version 2 as * published by the Free Software Foundation.  You may not use, modify or * distribute this program under any other version of the GNU General * Public License. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. * * Copyright (C) 2005 Sourcefire Inc. * * Author: Steven Sturges * * Purpose: *      Supports preprocessor defined rule options. * * Arguments: *      Required: *        None *      Optional: *        None * *   sample rules: *   alert tcp any any -> any any (msg: "DynamicRuleCheck"; ); * * Effect: * *      Returns 1 if the option matches, 0 if it doesn't. * * Comments: * * */#ifdef DYNAMIC_PLUGIN#ifdef HAVE_CONFIG_H#include "config.h"#endif#include <sys/types.h>#include <stdlib.h>#include <ctype.h>#ifdef HAVE_STRINGS_H#include <strings.h>#endif#include <errno.h>#include "plugbase.h"#include "rules.h"#include "debug.h"#include "util.h"#include "sf_dynamic_engine.h"#include "sfghash.h"SFGHASH *preprocRulesOptions = NULL;extern const u_int8_t *doe_ptr;typedef struct _PreprocessorOptionInfo{    PreprocOptionInit optionInit;    PreprocOptionEval optionEval;    PreprocOptionCleanup optionCleanup;    void             *data;} PreprocessorOptionInfo;void PreprocessorRuleOptionsInit(){    preprocRulesOptions = sfghash_new(10, 0, 0, NULL);}void PreprocessorRuleOptionsFree(){    if (preprocRulesOptions)    {        sfghash_delete(preprocRulesOptions);        preprocRulesOptions = NULL;    }}int RegisterPreprocessorRuleOption(char *optionName, PreprocOptionInit initFunc,                                   PreprocOptionEval evalFunc,                                   PreprocOptionCleanup cleanupFunc){    int ret;    PreprocessorOptionInfo *optionInfo;    if (!preprocRulesOptions)    {        FatalError("Preprocessor Rule Option storage not initialized\n");    }    optionInfo = sfghash_find(preprocRulesOptions, optionName);    if (optionInfo)    {        FatalError("Duplicate Preprocessor Rule Option '%s'\n", optionName);    }    optionInfo = (PreprocessorOptionInfo *)SnortAlloc(sizeof(PreprocessorOptionInfo));    optionInfo->optionEval = evalFunc;    optionInfo->optionInit = initFunc;    ret = sfghash_add(preprocRulesOptions, optionName, optionInfo);    if (ret != SFGHASH_OK)    {        FatalError("Failed to initialize Preprocessor Rule Option '%s'\n");    }    return 0;}int GetPreprocessorRuleOptionFuncs(char *optionName, void **initFunc, void **evalFunc){    PreprocessorOptionInfo *optionInfo;    if (!preprocRulesOptions)    {        FatalError("Preprocessor Rule Option storage not initialized\n");    }    optionInfo = sfghash_find(preprocRulesOptions, optionName);    if (!optionInfo)    {        return 0;    }    *initFunc = optionInfo->optionInit;    *evalFunc = optionInfo->optionEval;    return 1;}/* Callback function for dynamic preprocessor options */int PreprocessorOptionFunc(Packet *p, struct _OptTreeNode *otn, OptFpList *fp_list){    PreprocessorOptionInfo *optionInfo;    const u_int8_t *cursor = NULL;    int       success;    optionInfo = (PreprocessorOptionInfo *) fp_list->context;    //  Call eval function    success = optionInfo->optionEval(p, &cursor, optionInfo->data);    if ( cursor )        doe_ptr = cursor;    //  If successful, call next function in chain    if ( success )        return fp_list->next->OptTestFunc(p, otn, fp_list->next);    return 0;}int AddPreprocessorRuleOption(char *optionName, OptTreeNode *otn, void *data, PreprocOptionEval evalFunc){    OptFpList *fpl;    PreprocessorOptionInfo *optionInfo;    PreprocessorOptionInfo *saveOptionInfo;    optionInfo = sfghash_find(preprocRulesOptions, optionName);        if (!optionInfo)        return 0;    saveOptionInfo = (PreprocessorOptionInfo *)SnortAlloc(sizeof(PreprocessorOptionInfo));    memcpy(saveOptionInfo, optionInfo, sizeof(PreprocessorOptionInfo));    saveOptionInfo->data = data;    //  Add to option chain with generic callback    fpl = AddOptFuncToList(PreprocessorOptionFunc, otn);    /*     * attach custom info to the context node so that we can call each instance     * individually     */    fpl->context = (void *) saveOptionInfo;    return 1;}#endif /* DYNAMIC_PLUGIN */