/*
* ModSecurity for Apache 2.x, http://www.modsecurity.org/
* Copyright (c) 2004-2011 Trustwave Holdings, Inc. (http://www.trustwave.com/)
*
* You may not use this file except in compliance with
* the License.  You may obtain a copy of the License at
*
*     http://www.apache.org/licenses/LICENSE-2.0
*
* If any of the files related to licensing are missing or if you have any
* other questions related to licensing please contact Trustwave Holdings, Inc.
* directly using the email address security@modsecurity.org.
*/

#include <ctype.h>

#include "re.h"

#if defined(WITH_LUA)
#include "msc_lua.h"
#endif

static const char *const severities[] = {
    "EMERGENCY",
    "ALERT",
    "CRITICAL",
    "ERROR",
    "WARNING",
    "NOTICE",
    "INFO",
    "DEBUG",
    NULL,
};

/* -- Actions, variables, functions and operator functions ----------------- */

char *update_rule_target(cmd_parms *cmd, directory_config *dcfg,
        msre_ruleset *rset, const char *p1, const char *p2, const char *p3)
{
    msre_var **targets = NULL;
    msre_rule *rule = NULL;
    msre_ruleset *ruleset = NULL;
    const char *curr_targets = NULL;
    char *my_error_msg = NULL;
    char *p = NULL, *savedptr = NULL;
    char *target_list = NULL, *replace = NULL;
    int is_negated = 0, is_counting = 0;
    int name_len = 0, value_len = 0;
    char *name = NULL, *value = NULL;
    char *opt = NULL, *param = NULL;
    int i, rc, match = 0;
    int offset = 0;

    if(p1 == NULL || p2 == NULL || (dcfg == NULL && rset == NULL))  {
        return NULL;
    }

    if(dcfg != NULL)
        ruleset = dcfg->ruleset;
    else if (rset != NULL)
        ruleset = rset;

    /* Get the ruleset if one exists */
    if ((ruleset == NULL)||(ruleset == NOT_SET_P)) {
        return NULL;
    }
    rule = msre_ruleset_fetch_rule(ruleset, p1, offset);
    if (rule == NULL) {
        return NULL;
    }

    target_list = strdup(p2);
    if(target_list == NULL)
        return NULL;

    if(p3 != NULL)  {
        replace = strdup(p3);
        if(replace == NULL) {
            free(target_list);
            return NULL;
        }
    }

    if(replace != NULL) {

        opt = strchr(replace,'!');

        if(opt != NULL)  {
            *opt = '\0';
            opt++;
            param = opt;
            is_negated = 1;
        } else if ((opt = strchr(replace,'&')) != NULL)  {
            *opt = '\0';
            opt++;
            param = opt;
            is_counting = 1;
        } else  {
            param = replace;
        }

        opt = strchr(param,':');

        if(opt != NULL) {
            name = apr_strtok(param,":",&value);
            if(strchr(value,':') != NULL)   {
                goto end;
            }
        } else {
            name = param;
        }

        name_len = strlen(name);

        if(value != NULL)
            value_len = strlen(value);

        targets = (msre_var **)rule->targets->elts;
        // TODO need a good way to remove the element from array, maybe change array by tables or rings
        for (i = 0; i < rule->targets->nelts; i++) {
            if((strncasecmp(targets[i]->name,name,name_len) == 0) &&
                    (targets[i]->is_negated == is_negated) &&
                    (targets[i]->is_counting == is_counting))    {

                if(value != NULL && targets[i]->param != NULL)  {
                    if(strncasecmp(targets[i]->param,value,value_len) == 0) {
                        memset(targets[i]->name,0,strlen(targets[i]->name));
                        memset(targets[i]->param,0,strlen(targets[i]->param));
                        match = 1;
                    }
                } else if (value == NULL && targets[i]->param == NULL){
                    memset(targets[i]->name,0,strlen(targets[i]->name));
                    match = 1;
                } else
                    continue;

            }
        }
    }

    p = apr_strtok(target_list, ",", &savedptr);

    while(p != NULL) {

        if(replace != NULL) {
            if(match == 1)  {
                rc = msre_parse_targets(ruleset, p, rule->targets, &my_error_msg);
                if (rc < 0) {
                    goto end;
                }
            } else  {
                goto end;
            }
        } else {

            rc = msre_parse_targets(ruleset, p, rule->targets, &my_error_msg);
            if (rc < 0) {
                goto end;
            }
        }

        p = apr_strtok(NULL,",",&savedptr);
    }

    curr_targets = msre_generate_target_string(ruleset->mp, rule);

    rule->unparsed = msre_rule_generate_unparsed(ruleset->mp, rule, curr_targets, NULL, NULL);

end:
    if(target_list != NULL)
        free(target_list);
    if(replace != NULL)
        free(replace);
    return NULL;
}


/**
 * Remove actions with the same cardinality group from the actionset.
 */
static void msre_actionset_cardinality_fixup(msre_actionset *actionset, msre_action *action) {
    const apr_array_header_t *tarr = NULL;
    const apr_table_entry_t *telts = NULL;
    int i;

    if ((actionset == NULL) || (action == NULL)) return;

    tarr = apr_table_elts(actionset->actions);
    telts = (const apr_table_entry_t*)tarr->elts;

    for (i = 0; i < tarr->nelts; i++) {
        msre_action *target = (msre_action *)telts[i].val;
        if (target->metadata->cardinality_group == action->metadata->cardinality_group) {

            apr_table_unset(actionset->actions, target->metadata->name);
        }
    }
}

char *msre_generate_target_string(apr_pool_t *pool, msre_rule *rule)  {

    char *target_str = NULL;
    msre_var **targets = NULL;
    int i = 0;

    targets = (msre_var **)rule->targets->elts;

    for (i = 0; i < rule->targets->nelts; i++) {

        if(targets[i]->name != NULL && strlen(targets[i]->name) > 0)    {
        target_str = apr_pstrcat(pool,
                (target_str == NULL) ? "" : apr_psprintf(pool, "%s|", target_str),
                (targets[i]->is_negated == 0) ? "" : "!",
                (targets[i]->is_counting == 0) ? "" : "&",
                (targets[i]->name == NULL) ? "" : targets[i]->name,
                (targets[i]->param == NULL) ? "" : apr_psprintf(pool, ":%s", targets[i]->param),
                NULL);
        }

    }

    return target_str;
}

/**
 * Generate an action string from an actionset.
 */
char *msre_actionset_generate_action_string(apr_pool_t *pool, const msre_actionset *actionset)  {
    const apr_array_header_t *tarr = NULL;
    const apr_table_entry_t *telts = NULL;
    char *actions = NULL;
    int chain;
    int i;

    if (actionset == NULL) return NULL;

    chain = ((actionset->rule != NOT_SET_P) && actionset->rule->chain_starter) ? 1 : 0;

    tarr = apr_table_elts(actionset->actions);
    telts = (const apr_table_entry_t*)tarr->elts;

    for (i = 0; i < tarr->nelts; i++) {
        msre_action *action = (msre_action *)telts[i].val;
        int use_quotes = 0;

        if (chain) {
            /* Skip some actions that are not used in a chain. */
            if (   (action->metadata->type == ACTION_DISRUPTIVE)
                || (action->metadata->type == ACTION_METADATA)
                || (strcmp("log", action->metadata->name) == 0)
                || (strcmp("auditlog", action->metadata->name) == 0)
                || (strcmp("nolog", action->metadata->name) == 0)
                || (strcmp("noauditlog", action->metadata->name) == 0)
                || (strcmp("severity", action->metadata->name) == 0)
                || (strcmp("tag", action->metadata->name) == 0)
                || (strcmp("phase", action->metadata->name) == 0)) 
            {
                continue;
            }
        }

        /* Check if we need any quotes */
        if (action->param != NULL) {
            int j;
            for(j = 0; action->param[j] != '\0'; j++) {
                if (isspace(action->param[j])) {
                    use_quotes = 1;
                    break;
                }
            }
            if (j == 0) use_quotes = 1;
        }

        actions = apr_pstrcat(pool,
            (actions == NULL) ? "" : actions,
            (actions == NULL) ? "" : ",",
            action->metadata->name,
            (action->param == NULL) ? "" : ":",
            (use_quotes) ? "'" : "",
            (action->param == NULL) ? "" : action->param,
            (use_quotes) ? "'" : "",
            NULL);
    }

    return actions;
}

/**
 * Add an action to an actionset.
 */
static void msre_actionset_action_add(msre_actionset *actionset, msre_action *action)
{
    msre_action *add_action = action;

    if ((actionset == NULL)) return;

    /**
     * The "block" action is just a placeholder for the parent action.
     */
    if ((actionset->parent_intercept_action_rec != NULL) && (actionset->parent_intercept_action_rec != NOT_SET_P) && (strcmp("block", action->metadata->name) == 0) && (strcmp("block", action->metadata->name) == 0)) {
        /* revert back to parent */
        actionset->intercept_action = actionset->parent_intercept_action;
        add_action = actionset->parent_intercept_action_rec;
    }

    if ((add_action == NULL)) return;

    if (add_action->metadata->cardinality_group != ACTION_CGROUP_NONE) {
        msre_actionset_cardinality_fixup(actionset, add_action);
    }

    if (add_action->metadata->cardinality == ACTION_CARDINALITY_ONE) {
        /* One action per actionlist. */
        apr_table_setn(actionset->actions, add_action->metadata->name, (void *)add_action);
    } else {
        /* Multiple actions per actionlist. */
        apr_table_addn(actionset->actions, add_action->metadata->name, (void *)add_action);
    }
}

/**
 * Creates msre_var instances (rule variables) out of the
 * given text string and places them into the supplied table.
 */
apr_status_t msre_parse_targets(msre_ruleset *ruleset, const char *text,
    apr_array_header_t *arr, char **error_msg)
{
    const apr_array_header_t *tarr;
    const apr_table_entry_t *telts;
    apr_table_t *vartable;
    unsigned int count = 0;
    apr_status_t rc;
    msre_var *var;
    int i;

    if (text == NULL) return -1;

    /* Extract name & value pairs first */
    vartable = apr_table_make(ruleset->mp, 10);
    if (vartable == NULL) return -1;
    rc = msre_parse_generic(ruleset->mp, text, vartable, error_msg);
    if (rc < 0) return rc;

    /* Loop through the table and create variables */
    tarr = apr_table_elts(vartable);
    telts = (const apr_table_entry_t*)tarr->elts;
    for (i = 0; i < tarr->nelts; i++) {
        var = msre_create_var(ruleset, telts[i].key, telts[i].val, NULL, error_msg);
        if (var == NULL) return -1;
        *(msre_var **)apr_array_push(arr) = var;
        count++;
    }

    return count;
}

/**
 * Creates msre_action instances by parsing the given string, placing
 * them into the supplied array.
 */
apr_status_t msre_parse_actions(msre_engine *engine, msre_actionset *actionset,
    const char *text, char **error_msg)
{
    const apr_array_header_t *tarr;
    const apr_table_entry_t *telts;
    apr_table_t *vartable;
    unsigned int count = 0;
    apr_status_t rc;
    msre_action *action;
    int i;

    if (text == NULL) return -1;

    /* Extract name & value pairs first */
    vartable = apr_table_make(engine->mp, 10);
    if (vartable == NULL) return -1;
    rc = msre_parse_generic(engine->mp, text, vartable, error_msg);
    if (rc < 0) return rc;

    /* Loop through the table and create actions */
    tarr = apr_table_elts(vartable);
    telts = (const apr_table_entry_t*)tarr->elts;
    for (i = 0; i < tarr->nelts; i++) {
        /* Create action. */
        action = msre_create_action(engine, telts[i].key, telts[i].val, error_msg);
        if (action == NULL) return -1;

        /* Initialise action (option). */
        if (action->metadata->init != NULL) {
            action->metadata->init(engine, actionset, action);
        }

        msre_actionset_action_add(actionset, action);

        count++;
    }

    return count;
}

/**
 * Locates variable metadata given the variable name.
 */
msre_var_metadata *msre_resolve_var(msre_engine *engine, const char *name)
{
    return (msre_var_metadata *)apr_table_get(engine->variables, name);
}

/**
 * Locates action metadata given the action name.
 */
msre_action_metadata *msre_resolve_action(msre_engine *engine, const char *name)
{
    return (msre_action_metadata *)apr_table_get(engine->actions, name);
}

/**
 * Locates request body processor metadata given the processor name.
 */
msre_reqbody_processor_metadata *msre_resolve_reqbody_processor(
                                                            msre_engine *engine,
                                                            const char *name)
{
    return (msre_reqbody_processor_metadata *)apr_table_get(engine->reqbody_processors, name);
}

/**
 * Creates a new variable instance given the variable name
 * and an (optional) parameter.
 */
msre_var *msre_create_var_ex(apr_pool_t *pool, msre_engine *engine, const char *name, const char *param,
        modsec_rec *msr, char **error_msg)
{
    const char *varparam = param;
    msre_var *var = apr_pcalloc(pool, sizeof(msre_var));
    if (var == NULL) return NULL;

    if (error_msg == NULL) return NULL;
    *error_msg = NULL;

    /* Handle negation and member counting */
    if (name[0] == '!') {
        var->is_negated = 1;
        var->name = (char *)name + 1;
    }
    else
        if (name[0] == '&') {
            var->is_counting = 1;
            var->name = (char *)name + 1;
        }
        else {
            var->name = (char *)name;
        }

    /* Treat HTTP_* targets as an alias for REQUEST_HEADERS:* */
    if (   (var->name != NULL)
            && (strlen(var->name) > 5)
            && (strncmp("HTTP_", var->name, 5) == 0))
    {
        const char *oldname = var->name;
        var->name = apr_pstrdup(pool, "REQUEST_HEADERS");
        varparam = apr_pstrdup(pool, oldname + 5);
    }


    /* Resolve variable */
    var->metadata = msre_resolve_var(engine, var->name);
    if (var->metadata == NULL) {
        *error_msg = apr_psprintf(engine->mp, "Unknown variable: %s", name);
        return NULL;
    }

    /* The counting operator "&" can only be used against collections. */
    if (var->is_counting) {
        if (var->metadata->type == VAR_SIMPLE) {
            *error_msg = apr_psprintf(engine->mp, "The & modificator does not apply to "
                    "non-collection variables.");
            return NULL;
        }
    }

    /* Check the parameter. */
    if (varparam == NULL) {
        if (var->metadata->argc_min > 0) {
            *error_msg = apr_psprintf(engine->mp, "Missing mandatory parameter for variable %s.",
                    name);
            return NULL;
        }
    } else { /* Parameter present */

        /* Do we allow a parameter? */
        if (var->metadata->argc_max == 0) {
            *error_msg = apr_psprintf(engine->mp, "Variable %s does not support parameters.",
                    name);
            return NULL;
        }

        var->param = (char *)varparam;

    }

    return var;
}

/**
 * Create a new variable object from the provided name and value.
 *
 * NOTE: this allocates out of the global pool and should not be used
 *       per-request
 */
msre_var *msre_create_var(msre_ruleset *ruleset, const char *name, const char *param,
        modsec_rec *msr, char **error_msg)
{
    msre_var *var = msre_create_var_ex(ruleset->engine->mp, ruleset->engine, name, param, msr, error_msg);
    if (var == NULL) return NULL;

    /* Validate & initialise variable */
    if (var->metadata->validate != NULL) {
        *error_msg = var->metadata->validate(ruleset, var);
        if (*error_msg != NULL) {
            return NULL;
        }
    }

    return var;
}

/**
 * Creates a new action instance given its name and an (optional) parameter.
 */
msre_action *msre_create_action(msre_engine *engine, const char *name, const char *param,
    char **error_msg)
{
    msre_action *action = apr_pcalloc(engine->mp, sizeof(msre_action));
    if (action == NULL) return NULL;

    if (error_msg == NULL) return NULL;
    *error_msg = NULL;

    /* Resolve action */
    action->metadata = msre_resolve_action(engine, name);
    if (action->metadata == NULL) {
        *error_msg = apr_psprintf(engine->mp, "Unknown action: %s", name);
        return NULL;
    }

    if (param == NULL) { /* Parameter not present */
        if (action->metadata->argc_min > 0) {
            *error_msg = apr_psprintf(engine->mp, "Missing mandatory parameter for action %s",
                name);
            return NULL;
        }
    } else { /* Parameter present */

        /* Should we allow the parameter? */
        if (action->metadata->argc_max == 0) {
            *error_msg = apr_psprintf(engine->mp, "Extra parameter provided to action %s", name);
            return NULL;
        }

        /* Handle +/- modificators */
        if ((param[0] == '+')||(param[0] == '-')) {
            if (action->metadata->allow_param_plusminus == 0) {
                *error_msg = apr_psprintf(engine->mp,
                     "Action %s does not allow +/- modificators.", name);
                return NULL;
            }
            else { /* Modificators allowed. */
                if (param[0] == '+') {
                    action->param = param + 1;
                    action->param_plusminus = POSITIVE_VALUE;
                } else
                if (param[0] == '-') {
                    action->param = param + 1;
                    action->param_plusminus = NEGATIVE_VALUE;
                }
            }
        } else {
            action->param = param;
        }

        /* Validate parameter */
        if (action->metadata->validate != NULL) {
            *error_msg = action->metadata->validate(engine, action);
            if (*error_msg != NULL) return NULL;
        }
    }

    return action;
}

/**
 * Generic parser that is used as basis for target and action parsing.
 * It breaks up the input string into name-parameter pairs and places
 * them into the given table.
 */
int msre_parse_generic(apr_pool_t *mp, const char *text, apr_table_t *vartable,
    char **error_msg)
{
    char *p = (char *)text;
    int count = 0;

    if (error_msg == NULL) return -1;
    *error_msg = NULL;

    count = 0;
    while(*p != '\0') {
        char *name = NULL, *value = NULL;

        /* ignore whitespace */
        while(isspace(*p)) p++;
        if (*p == '\0') return count;

        /* we are at the beginning of the name */
        name = p;
        while((*p != '\0')&&(*p != '|')&&(*p != ':')&&(*p != ',')&&(!isspace(*p))) p++; /* ENH replace with isvarnamechar() */

        /* get the name */
        name = apr_pstrmemdup(mp, name, p - name);

        if (*p != ':') { /* we don't have a parameter */
            /* add to the table with no value */
            apr_table_addn(vartable, name, NULL);
            count++;

            /* go over any whitespace present */
            while(isspace(*p)) p++;

            /* we're done */
            if (*p == '\0') {
                return count;
            }

            /* skip over the separator character and continue */
            if ((*p == ',')||(*p == '|')) {
                p++;
                continue;
            }

            *error_msg = apr_psprintf(mp, "Unexpected character at position %d: %s",
                (int)(p - text), text);
            return -1;
        }

        /* we have a parameter */

        p++; /* move over the colon */

        /* we'll allow empty values */
        if (*p == '\0') {
            apr_table_addn(vartable, name, NULL);
            count++;
            return count;
        }

        if ((*p == ',')||(*p == '|')) {
            apr_table_addn(vartable, name, NULL);
            count++;
            /* move over the separator char and continue */
            p++;
            continue;
        }

        /* we really have a parameter */

        if (*p == '\'') { /* quoted value */
            char *d = NULL;

            p++; /* go over the openning quote */
            value = d = strdup(p);
            if (d == NULL) return -1;

            for(;;) {
                if (*p == '\0') {
                    *error_msg = apr_psprintf(mp, "Missing closing quote at position %d: %s",
                        (int)(p - text), text);
                    free(value);
                    return -1;
                } else
                if (*p == '\\') {
                    if ( (*(p + 1) == '\0') || ((*(p + 1) != '\'')&&(*(p + 1) != '\\')) ) {
                        *error_msg = apr_psprintf(mp, "Invalid quoted pair at position %d: %s",
                            (int)(p - text), text);
                        free(value);
                        return -1;
                    }
                    p++;
                    *(d++) = *(p++);
                } else
                if (*p == '\'') {
                    *d = '\0';
                    p++;
                    break;
                }
                else {
                    *(d++) = *(p++);
                }
            }

            d = value;
            value = apr_pstrdup(mp, d);
            free(d);
        } else { /* non-quoted value */
            value = p;
            while((*p != '\0')&&(*p != ',')&&(*p != '|')&&(!isspace(*p))) p++;
            value = apr_pstrmemdup(mp, value, p - value);
        }

        /* add to table */
        apr_table_addn(vartable, name, value);
        count++;

        /* move to the first character of the next name-value pair */
        while(isspace(*p)||(*p == ',')||(*p == '|')) p++;
    }

    return count;
}


/* -- Actionset functions -------------------------------------------------- */

/**
 * Creates an actionset instance and (as an option) populates it by
 * parsing the given string which contains a list of actions.
 */
msre_actionset *msre_actionset_create(msre_engine *engine, const char *text,
    char **error_msg)
{
    msre_actionset *actionset = (msre_actionset *)apr_pcalloc(engine->mp,
        sizeof(msre_actionset));
    if (actionset == NULL) return NULL;

    actionset->actions = apr_table_make(engine->mp, 25);
    if (actionset->actions == NULL) return NULL;

    /* Metadata */
    actionset->id = NOT_SET_P;
    actionset->rev = NOT_SET_P;
    actionset->msg = NOT_SET_P;
    actionset->logdata = NOT_SET_P;
    actionset->phase = NOT_SET;
    actionset->severity = -1;
    actionset->rule = NOT_SET_P;
    actionset->arg_max = -1;
    actionset->arg_min = -1;

    /* Flow */
    actionset->is_chained = NOT_SET;
    actionset->skip_count = NOT_SET;
    actionset->skip_after = NOT_SET_P;

    /* Disruptive */
    actionset->parent_intercept_action_rec = NOT_SET_P;
    actionset->intercept_action_rec = NOT_SET_P;
    actionset->parent_intercept_action = NOT_SET;
    actionset->intercept_action = NOT_SET;
    actionset->intercept_uri = NOT_SET_P;
    actionset->intercept_status = NOT_SET;
    actionset->intercept_pause = NOT_SET;

    /* Other */
    actionset->auditlog = NOT_SET;
    actionset->log = NOT_SET;

    /* Parse the list of actions, if it's present */
    if (text != NULL) {
        if (msre_parse_actions(engine, actionset, text, error_msg) < 0) {
            return NULL;
        }
    }

    return actionset;
}

/**
 * Create a (shallow) copy of the supplied actionset.
 */
static msre_actionset *msre_actionset_copy(apr_pool_t *mp, msre_actionset *orig) {
    msre_actionset *copy = NULL;

    if (orig == NULL) return NULL;
    copy = (msre_actionset *)apr_pmemdup(mp, orig, sizeof(msre_actionset));
    if (copy == NULL) return NULL;
    copy->actions = apr_table_copy(mp, orig->actions);

    return copy;
}

/**
 * Merges two actionsets into one.
 */
msre_actionset *msre_actionset_merge(msre_engine *engine, msre_actionset *parent,
    msre_actionset *child, int inherit_by_default)
{
    msre_actionset *merged = NULL;
    const apr_array_header_t *tarr;
    const apr_table_entry_t *telts;
    int i;

    if (inherit_by_default == 0) {
        /* There is nothing to merge in this case. */
        return msre_actionset_copy(engine->mp, child);
    }

    /* Start with a copy of the parent configuration. */
    merged = msre_actionset_copy(engine->mp, parent);
    if (merged == NULL) return NULL;

    if (child == NULL) {
        /* The child actionset does not exist, hence
         * go with the parent one.
         */
        return merged;
    }

    /* First merge the hard-coded stuff. */

    /* Metadata */
    if (child->id != NOT_SET_P) merged->id = child->id;
    if (child->rev != NOT_SET_P) merged->rev = child->rev;
    if (child->msg != NOT_SET_P) merged->msg = child->msg;
    if (child->logdata != NOT_SET_P) merged->logdata = child->logdata;
    if (child->severity != NOT_SET) merged->severity = child->severity;
    if (child->phase != NOT_SET) merged->phase = child->phase;
    if (child->rule != NOT_SET_P) merged->rule = child->rule;
    if (child->arg_min != NOT_SET) merged->arg_min = child->arg_min;
    if (child->arg_max != NOT_SET) merged->arg_max = child->arg_max;

    /* Flow */
    merged->is_chained = child->is_chained;
    if (child->skip_count != NOT_SET) merged->skip_count = child->skip_count;
    if (child->skip_after != NOT_SET_P) merged->skip_after = child->skip_after;

    /* Disruptive */
    if (child->intercept_action != NOT_SET) {
        merged->intercept_action_rec = child->intercept_action_rec;
        merged->intercept_action = child->intercept_action;
        merged->intercept_uri = child->intercept_uri;
    }

    if (child->intercept_status != NOT_SET) merged->intercept_status = child->intercept_status;
    if (child->intercept_pause != NOT_SET) merged->intercept_pause = child->intercept_pause;

    /* Other */
    if (child->auditlog != NOT_SET) merged->auditlog = child->auditlog;
    if (child->log != NOT_SET) merged->log = child->log;


    /* Now merge the actions. */

    tarr = apr_table_elts(child->actions);
    telts = (const apr_table_entry_t*)tarr->elts;
    for (i = 0; i < tarr->nelts; i++) {
        msre_actionset_action_add(merged, (msre_action *)telts[i].val);
    }

    return merged;
}

/**
 * Creates an actionset that contains a default list of actions.
 */
msre_actionset *msre_actionset_create_default(msre_engine *engine) {
    char  *my_error_msg = NULL;
    return msre_actionset_create(engine,
        "phase:2,log,auditlog,pass",
        &my_error_msg);
}

/**
 * Sets the default values for the hard-coded actionset configuration.
 */
void msre_actionset_set_defaults(msre_actionset *actionset) {
    /* Metadata */
    if (actionset->id == NOT_SET_P) actionset->id = NULL;
    if (actionset->rev == NOT_SET_P) actionset->rev = NULL;
    if (actionset->msg == NOT_SET_P) actionset->msg = NULL;
    if (actionset->logdata == NOT_SET_P) actionset->logdata = NULL;
    if (actionset->phase == NOT_SET) actionset->phase = 2;
    if (actionset->severity == -1) {} /* leave at -1 */
    if (actionset->rule == NOT_SET_P) actionset->rule = NULL;
    if (actionset->arg_max == NOT_SET) actionset->arg_max = -1;
    if (actionset->arg_min == NOT_SET) actionset->arg_min = -1;

    /* Flow */
    if (actionset->is_chained == NOT_SET) actionset->is_chained = 0;
    if (actionset->skip_count == NOT_SET) actionset->skip_count = 0;
    if (actionset->skip_after == NOT_SET_P) actionset->skip_after = NULL;

    /* Disruptive */
    if (actionset->parent_intercept_action_rec == NOT_SET_P) actionset->parent_intercept_action_rec = NULL;
    if (actionset->intercept_action_rec == NOT_SET_P) actionset->intercept_action_rec = NULL;
    if (actionset->parent_intercept_action == NOT_SET) actionset->parent_intercept_action = ACTION_NONE;
    if (actionset->intercept_action == NOT_SET) actionset->intercept_action = ACTION_NONE;
    if (actionset->intercept_uri == NOT_SET_P) actionset->intercept_uri = NULL;
    if (actionset->intercept_status == NOT_SET) actionset->intercept_status = 403;
    if (actionset->intercept_pause == NOT_SET) actionset->intercept_pause = 0;

    /* Other */
    if (actionset->auditlog == NOT_SET) actionset->auditlog = 1;
    if (actionset->log == NOT_SET) actionset->log = 1;
}

/* -- Engine functions ----------------------------------------------------- */

/**
 * Creates a new engine instance.
 */
msre_engine *msre_engine_create(apr_pool_t *parent_pool) {
    msre_engine *engine;
    apr_pool_t *mp;

    /* Create new memory pool */
    if (apr_pool_create(&mp, parent_pool) != APR_SUCCESS) return NULL;

    /* Init fields */
    engine = apr_pcalloc(mp, sizeof(msre_engine));
    if (engine == NULL) return NULL;
    engine->mp = mp;
    engine->tfns = apr_table_make(mp, 50);
    if (engine->tfns == NULL) return NULL;
    engine->operators = apr_table_make(mp, 25);
    if (engine->operators == NULL) return NULL;
    engine->variables = apr_table_make(mp, 100);
    if (engine->variables == NULL) return NULL;
    engine->actions = apr_table_make(mp, 50);
    if (engine->actions == NULL) return NULL;
    engine->reqbody_processors = apr_table_make(mp, 10);
    if (engine->reqbody_processors == NULL) return NULL;

    return engine;
}

/**
 * Destroys an engine instance, releasing the consumed memory.
 */
void msre_engine_destroy(msre_engine *engine) {
    /* Destroyed automatically by the parent pool.
     * apr_pool_destroy(engine->mp);
     */
}


/* -- Recipe functions ----------------------------------------------------- */

#define NEXT_CHAIN  1
#define NEXT_RULE   2
#define SKIP_RULES  3



/**
 * Default implementation of the ruleset phase processing; it processes
 * the rules in the ruleset attached to the currently active
 * transaction phase.
 */
#if defined(PERFORMANCE_MEASUREMENT)

#define PERFORMANCE_MEASUREMENT_LOOP 5000

static apr_status_t msre_ruleset_process_phase_(msre_ruleset *ruleset, modsec_rec *msr);

apr_status_t msre_ruleset_process_phase(msre_ruleset *ruleset, modsec_rec *msr) {
    apr_array_header_t *arr = NULL;
    msre_rule **rules = NULL;
    apr_status_t rc;
    int i;

    switch (msr->phase) {
        case PHASE_REQUEST_HEADERS :
            arr = ruleset->phase_request_headers;
            break;
        case PHASE_REQUEST_BODY :
            arr = ruleset->phase_request_body;
            break;
        case PHASE_RESPONSE_HEADERS :
            arr = ruleset->phase_response_headers;
            break;
        case PHASE_RESPONSE_BODY :
            arr = ruleset->phase_response_body;
            break;
        case PHASE_LOGGING :
            arr = ruleset->phase_logging;
            break;
        default :
            msr_log(msr, 1, "Internal Error: Invalid phase %d", msr->phase);
            return -1;
    }

    rules = (msre_rule **)arr->elts;
    for (i = 0; i < arr->nelts; i++) {
        msre_rule *rule = rules[i];
        rule->execution_time = 0;
    }

    for (i = 0; i < PERFORMANCE_MEASUREMENT_LOOP; i++) {
        rc = msre_ruleset_process_phase_(ruleset, msr);
    }

    msr_log(msr, 1, "Phase %d", msr->phase);

    rules = (msre_rule **)arr->elts;
    for (i = 0; i < arr->nelts; i++) {
        msre_rule *rule = rules[i];

        /* Ignore markers, which are never processed. */
        if (rule->placeholder == RULE_PH_MARKER) continue;

        msr_log(msr, 1, "Rule %pp [id \"%s\"][file \"%s\"][line \"%d\"]: %u usec", rule,
            ((rule->actionset != NULL)&&(rule->actionset->id != NULL)) ? rule->actionset->id : "-",
            rule->filename != NULL ? rule->filename : "-",
            rule->line_num,
            (rule->execution_time / PERFORMANCE_MEASUREMENT_LOOP));
    }

    return rc;
}

static apr_status_t msre_ruleset_process_phase_(msre_ruleset *ruleset, modsec_rec *msr) {
#else
apr_status_t msre_ruleset_process_phase(msre_ruleset *ruleset, modsec_rec *msr) {
#endif
    apr_array_header_t *arr = NULL;
    msre_rule **rules;
    apr_status_t rc;
    const char *skip_after = NULL;
    msre_rule *last_rule = NULL;
    msre_rule *rule_starter = NULL;
    int i, mode, skip, skipped, saw_starter;

    /* First determine which set of rules we need to use. */
    switch (msr->phase) {
        case PHASE_REQUEST_HEADERS :
            arr = ruleset->phase_request_headers;
            break;
        case PHASE_REQUEST_BODY :
            arr = ruleset->phase_request_body;
            break;
        case PHASE_RESPONSE_HEADERS :
            arr = ruleset->phase_response_headers;
            break;
        case PHASE_RESPONSE_BODY :
            arr = ruleset->phase_response_body;
            break;
        case PHASE_LOGGING :
            arr = ruleset->phase_logging;
            break;
        default :
            msr_log(msr, 1, "Internal Error: Invalid phase %d", msr->phase);
            return -1;
    }

    if (msr->txcfg->debuglog_level >= 9) {
        msr_log(msr, 9, "This phase consists of %d rule(s).", arr->nelts);
    }

    apr_table_clear(msr->matched_vars);

    /* Loop through the rules in the selected set. */
    skip = 0;
    skipped = 0;
    saw_starter = 0;
    mode = NEXT_RULE;
    rules = (msre_rule **)arr->elts;
    for (i = 0; i < arr->nelts; i++) {
        msre_rule *rule = rules[i];
#if defined(PERFORMANCE_MEASUREMENT)
        apr_time_t time1 = 0;
#endif

        /* Reset the rule interception flag */
        msr->rule_was_intercepted = 0;

        /* SKIP_RULES is used to skip all rules until we hit a placeholder
         * with the specified rule ID and then resume execution after that.
         */
        if (mode == SKIP_RULES) {
            /* Go to the next rule if we have not yet hit the skip_after ID */

            if ((rule->placeholder == RULE_PH_NONE) || (rule->actionset->id == NULL) || (strcmp(skip_after, rule->actionset->id) != 0)) {

                if(i-1 >=0)
                    last_rule = rules[i-1];
                else
                    last_rule = rules[0];

                if((last_rule != NULL) && (last_rule->actionset != NULL) && last_rule->actionset->is_chained && (saw_starter == 1)) {
                    mode = NEXT_RULE;
                    skipped = 1;
                    --i;
                } else {
                    mode = SKIP_RULES;
                    skipped = 0;
                    saw_starter = 0;

                    if (msr->txcfg->debuglog_level >= 9) {
                        msr_log(msr, 9, "Current rule is id=\"%s\" [chained %d] is trying to find the SecMarker=\"%s\" [stater %d]",rule->actionset->id,last_rule->actionset->is_chained,skip_after,saw_starter);
                    }

                }

                continue;
            }

            if (msr->txcfg->debuglog_level >= 9) {
                msr_log(msr, 9, "Found rule %pp id=\"%s\".", rule, skip_after);
            }

            /* Go to the rule *after* this one to continue execution. */
            if (msr->txcfg->debuglog_level >= 4) {
                msr_log(msr, 4, "Continuing execution after rule id=\"%s\".", skip_after);
            }

            saw_starter = 0;
            skipped = 0;
            skip_after = NULL;
            mode = NEXT_RULE;
            continue;
        }

        /* Skip any rule marked as a placeholder */
        if (rule->placeholder != RULE_PH_NONE) {
            continue;
        }

        /* NEXT_CHAIN is used when one of the rules in a chain
         * fails to match and then we need to skip the remaining
         * rules in that chain in order to get to the next
         * rule that can execute.
         */
        if (mode == NEXT_CHAIN) {
            if (rule->actionset->is_chained == 0) {
                mode = NEXT_RULE;
            }

            /* Go to the next rule. */
            continue;
        }

        /* If we are here that means the mode is NEXT_RULE, which
         * then means we have done processing any chains. However,
         * if the "skip" parameter is set we need to skip over.
         */
        if ((mode == NEXT_RULE)&&(skip > 0)) {
            /* Decrement the skip counter by one. */
            skip--;

            /* If the current rule is part of a chain then
             * we need to skip over the entire chain. Thus
             * we change the mode to NEXT_CHAIN. The skip
             * counter will not decrement as we are moving
             * over the rules belonging to the chain.
             */
            if (rule->actionset->is_chained) {
                mode = NEXT_CHAIN;
            }

            /* Go to the next rule. */
            continue;
        }

        /* Check if this rule was removed at runtime */
        if (((rule->actionset->id !=NULL) && !apr_is_empty_array(msr->removed_rules)) || (apr_is_empty_array(msr->removed_rules_tag)==0)) {
            int j, act;
            int do_process = 1;
            const char *range;
            const apr_array_header_t *tag_tarr = NULL;
            const apr_table_entry_t *tag_telts = NULL;

            for(j = 0; j < msr->removed_rules->nelts; j++) {
                range = ((const char**)msr->removed_rules->elts)[j];

                if(rule->actionset->id !=NULL)  {

                    if (msr->txcfg->debuglog_level >= 9) {
                        msr_log(msr, 9, "Checking removal of rule id=\"%s\" against: %s", rule->actionset->id, range);
                    }

                    if (rule_id_in_range(atoi(rule->actionset->id), range)) {
                        do_process = 0;
                        break;
                    }
                }
            }

            tag_tarr = apr_table_elts(rule->actionset->actions);
            tag_telts = (const apr_table_entry_t*)tag_tarr->elts;

            for (act = 0; act < tag_tarr->nelts; act++) {
                msre_action *action = (msre_action *)tag_telts[act].val;

                if((action != NULL) && (action->metadata != NULL ) && strcmp("tag", action->metadata->name) == 0)  {

                    for(j = 0; j < msr->removed_rules_tag->nelts; j++) {
                        range = ((const char**)msr->removed_rules_tag->elts)[j];


                        if(action->param != NULL)   {
                            /* Expand variables in the tag argument. */
                            msc_string *var = (msc_string *)apr_pcalloc(msr->mp, sizeof(msc_string));

                            var->value = (char *)action->param;
                            var->value_len = strlen(action->param);
                            expand_macros(msr, var, NULL, msr->mp);

                            if (msr->txcfg->debuglog_level >= 9) {
                                msr_log(msr, 9, "Checking removal of rule tag=\"%s\" against: %s", var->value, range);
                            }

                            if (strncasecmp(var->value, range, strlen(range)) == 0) {
                                do_process = 0;
                                break;
                            }
                        }
                    }
                }
            }

            /* Go to the next rule if this one has been removed. */
            if (do_process == 0) {
                if (msr->txcfg->debuglog_level >= 5) {
                    msr_log(msr, 5, "Not processing %srule id=\"%s\": "
                            "removed by ctl action",
                            rule->actionset->is_chained ? "chained " : "",
                            rule->actionset->id);
                }

                /* Skip the whole chain, if this is a chained rule */
                if (rule->actionset->is_chained) {
                    mode = NEXT_CHAIN;
                }

                skipped = 0;
                saw_starter = 0;
                continue;
            }
        }

        if(msr->txcfg->is_enabled == MODSEC_DISABLED)   {
            saw_starter = 0;
            skipped = 0;
            skip_after = NULL;
            mode = NEXT_RULE;
            continue;
        }

        if (msr->txcfg->debuglog_level >= 4) {
            apr_pool_t *p = msr->mp;
            const char *fn = NULL;
            const char *id = NULL;
            const char *rev = NULL;

            if (rule->filename != NULL) {
                fn = apr_psprintf(p, " [file \"%s\"] [line \"%d\"]", rule->filename, rule->line_num);
            }

            if (rule->actionset != NULL && rule->actionset->id != NULL) {
                id = apr_psprintf(p, " [id \"%s\"]", rule->actionset->id);
            }

            if (rule->actionset != NULL && rule->actionset->rev != NULL) {
                rev = apr_psprintf(p, " [rev \"%s\"]", rule->actionset->rev);
            }

            msr_log(msr, 4, "Recipe: Invoking rule %pp;%s%s%s.",
                    rule, (fn ? fn : ""), (id ? id : ""), (rev ? rev : ""));
            msr_log(msr, 5, "Rule %pp: %s", rule, rule->unparsed);
        }

#if defined(PERFORMANCE_MEASUREMENT)
        time1 = apr_time_now();
#endif

        rc = msre_rule_process(rule, msr);

#if defined(PERFORMANCE_MEASUREMENT)
        rule->execution_time += (apr_time_now() - time1);
#endif

        if (msr->txcfg->debuglog_level >= 4) {
            msr_log(msr, 4, "Rule returned %d.", rc);
        }

        if (rc == RULE_NO_MATCH) {
            if (rule->actionset->is_chained) {
                /* If the current rule is part of a chain then
                 * we need to skip over all the rules in the chain.
                 */
                mode = NEXT_CHAIN;
                if (msr->txcfg->debuglog_level >= 9) {
                    msr_log(msr, 9, "No match, chained -> mode NEXT_CHAIN.");
                }
            } else {
                /* This rule is not part of a chain so we simply
                 * move to the next rule.
                 */
                mode = NEXT_RULE;
                if (msr->txcfg->debuglog_level >= 9) {
                    msr_log(msr, 9, "No match, not chained -> mode NEXT_RULE.");
                }
            }

            apr_table_clear(msr->matched_vars);
            skipped = 0;
            saw_starter = 0;
        }
        else if (rc == RULE_MATCH) {
            if (msr->rule_was_intercepted) {
                /* If the transaction was intercepted by this rule we will
                 * go back. Do note that we are relying on the
                 * rule to know if it is a part of a chain and
                 * not intercept if it is.
                 */
                if (msr->txcfg->debuglog_level >= 9) {
                    msr_log(msr, 9, "Match, intercepted -> returning.");
                }

                if(i-1 >= 0)
                    last_rule = rules[i-1];
                else
                    last_rule = rules[0];

                if((last_rule != NULL) && (last_rule->actionset != NULL) && last_rule->actionset->is_chained) {

                    int st = 0;

                    for(st=i;st>=0;st--)  {

                        rule_starter = rules[st];

                        if(rule_starter != NULL && rule_starter->chain_starter != NULL)    {
                            if((msr != NULL) && (msr->intercept_actionset != NULL) && (rule_starter->actionset != NULL))
                                msr->intercept_actionset->intercept_uri = rule_starter->actionset->intercept_uri;
                            break;
                        }
                    }

                }

                apr_table_clear(msr->matched_vars);
                return 1;
            }

            if (rule->actionset->skip_after != NULL) {
                skip_after = rule->actionset->skip_after;
                mode = SKIP_RULES;
                saw_starter = 1;

                if (msr->txcfg->debuglog_level >= 9) {
                    msr_log(msr, 9, "Skipping after rule %pp id=\"%s\" -> mode SKIP_RULES.", rule, skip_after);
                }

                continue;
            }

            if(skipped == 1)    {
                mode = SKIP_RULES;
                continue;
            }

            /* We had a match but the transaction was not
             * intercepted. In that case we proceed with the
             * next rule...
             */
            mode = NEXT_RULE;
            if (msr->txcfg->debuglog_level >= 9) {
                msr_log(msr, 9, "Match -> mode NEXT_RULE.");
            }

            /* ...unless we need to skip, in which case we
             * determine how many rules/chains we need to
             * skip and configure the counter accordingly.
             */
            if (rule->actionset->is_chained == 0) {
                if (rule->chain_starter != NULL) {
                    if (rule->chain_starter->actionset->skip_count > 0) {
                        skip = rule->chain_starter->actionset->skip_count;
                        if (msr->txcfg->debuglog_level >= 4) {
                            msr_log(msr, 4, "Skipping %d rules/chains (from a chain).", skip);
                        }
                    }
                }
                else if (rule->actionset->skip_count > 0) {
                    skip = rule->actionset->skip_count;
                    if (msr->txcfg->debuglog_level >= 4) {
                        msr_log(msr, 4, "Skipping %d rules/chains.", skip);
                    }
                }
            }
        }
        else if (rc < 0) {
            msr_log(msr, 1, "Rule processing failed.");


            if (msr->txcfg->reqintercept_oe == 1)   {
                apr_table_clear(msr->matched_vars);
                return -1;
            } else  {
                if (rule->actionset->is_chained) {
                    /* If the current rule is part of a chain then
                     * we need to skip over all the rules in the chain.
                     */
                    mode = NEXT_CHAIN;
                    if (msr->txcfg->debuglog_level >= 9) {
                        msr_log(msr, 9, "Ruled failed, chained -> mode NEXT_CHAIN.");
                    }
                } else {
                    /* This rule is not part of a chain so we simply
                     * move to the next rule.
                     */
                    mode = NEXT_RULE;
                    if (msr->txcfg->debuglog_level >= 9) {
                        msr_log(msr, 9, "Rule failed, not chained -> mode NEXT_RULE.");
                    }
                }

                apr_table_clear(msr->matched_vars);
                skipped = 0;
                saw_starter = 0;
            }
        }
        else {
            msr_log(msr, 1, "Rule processing failed with unknown return code: %d.", rc);
            apr_table_clear(msr->matched_vars);
            return -1;
        }
    }

    /* ENH warn if chained rules are missing. */
    apr_table_clear(msr->matched_vars);
    return 0;
}

/**
 * Creates a ruleset that will be handled by the default
 * implementation.
 */
msre_ruleset *msre_ruleset_create(msre_engine *engine, apr_pool_t *mp) {
    msre_ruleset *ruleset;

    ruleset = apr_pcalloc(mp, sizeof(msre_ruleset));
    if (ruleset == NULL) return NULL;
    ruleset->mp = mp;
    ruleset->engine = engine;

    ruleset->phase_request_headers = apr_array_make(ruleset->mp, 25, sizeof(const msre_rule *));
    ruleset->phase_request_body = apr_array_make(ruleset->mp, 25, sizeof(const msre_rule *));
    ruleset->phase_response_headers = apr_array_make(ruleset->mp, 25, sizeof(const msre_rule *));
    ruleset->phase_response_body = apr_array_make(ruleset->mp, 25, sizeof(const msre_rule *));
    ruleset->phase_logging = apr_array_make(ruleset->mp, 25, sizeof(const msre_rule *));

    return ruleset;
}

/**
 * Adds one rule to the given phase of the ruleset.
 */
int msre_ruleset_rule_add(msre_ruleset *ruleset, msre_rule *rule, int phase) {
    apr_array_header_t *arr = NULL;

    switch (phase) {
        case PHASE_REQUEST_HEADERS :
            arr = ruleset->phase_request_headers;
            break;
        case PHASE_REQUEST_BODY :
            arr = ruleset->phase_request_body;
            break;
        case PHASE_RESPONSE_HEADERS :
            arr = ruleset->phase_response_headers;
            break;
        case PHASE_RESPONSE_BODY :
            arr = ruleset->phase_response_body;
            break;
        case PHASE_LOGGING :
            arr = ruleset->phase_logging;
            break;
        default :
            return -1;
    }

    /* ENH verify the rule's use of targets is consistent with
     * the phase it selected to run at.
     */

    msre_actionset_set_defaults(rule->actionset);
    rule->actionset->rule = rule;

    *(const msre_rule **)apr_array_push(arr) = rule;

    return 1;
}

static msre_rule * msre_ruleset_fetch_phase_rule(const msre_ruleset *ruleset, const char *id,
        const apr_array_header_t *phase_arr, int offset)
{
    msre_rule **rules = (msre_rule **)phase_arr->elts;
    int i;

    for (i = 0; i < phase_arr->nelts; i++) {
        msre_rule *rule = (msre_rule *)rules[i];

        /* Rule with an action, not a sub-rule (chain) and a matching id */
        if (  (rule->actionset != NULL)
                && (!rule->actionset->is_chained || !rule->chain_starter)
                && (rule->actionset->id != NULL)
                && (strcmp(rule->actionset->id, id) == 0))
        {
            /* Return rule that matched unless it is a placeholder */
            if(offset == 0) {
                return (rule->placeholder == RULE_PH_NONE) ? rule : NULL;
            }
            else    {
                if (i+offset < phase_arr->nelts)    {
                    msre_rule *rule_off = (msre_rule *)rules[i+offset];
                    return (rule_off->placeholder == RULE_PH_NONE) ? rule_off : NULL;
                }
            }
        }
    }

    return NULL;
}

/**
 * Fetches rule from the ruleset all rules that match the given exception.
 */
msre_rule * msre_ruleset_fetch_rule(msre_ruleset *ruleset, const char *id, int offset) {
    msre_rule *rule = NULL;

    if (ruleset == NULL) return NULL;

    rule = msre_ruleset_fetch_phase_rule(ruleset, id, ruleset->phase_request_headers, offset);
    if (rule != NULL) return rule;

    rule = msre_ruleset_fetch_phase_rule(ruleset, id, ruleset->phase_request_body, offset);
    if (rule != NULL) return rule;

    rule = msre_ruleset_fetch_phase_rule(ruleset, id, ruleset->phase_response_headers, offset);
    if (rule != NULL) return rule;

    rule = msre_ruleset_fetch_phase_rule(ruleset, id, ruleset->phase_response_body, offset);
    if (rule != NULL) return rule;

    rule = msre_ruleset_fetch_phase_rule(ruleset, id, ruleset->phase_logging, offset);

    return rule;
}

static int msre_ruleset_phase_rule_remove_with_exception(msre_ruleset *ruleset, rule_exception *re,
        apr_array_header_t *phase_arr)
{
    msre_rule **rules;
    int i, j, mode, removed_count;

    j = 0;
    mode = 0;
    removed_count = 0;
    rules = (msre_rule **)phase_arr->elts;
    for (i = 0; i < phase_arr->nelts; i++) {
        msre_rule *rule = (msre_rule *)rules[i];

        if (mode == 0) { /* Looking for next rule. */
            int remove_rule = 0;

            /* Only remove non-placeholder rules */
            if (rule->placeholder == RULE_PH_NONE) {
                switch(re->type) {
                    case RULE_EXCEPTION_REMOVE_ID :
                        if ((rule->actionset != NULL)&&(rule->actionset->id != NULL)) {
                            int ruleid = atoi(rule->actionset->id);

                            if (rule_id_in_range(ruleid, re->param)) {
                                remove_rule = 1;
                            }
                        }

                        break;

                    case RULE_EXCEPTION_REMOVE_MSG :
                        if ((rule->actionset != NULL)&&(rule->actionset->msg != NULL)) {
                            char *my_error_msg = NULL;

                            int rc = msc_regexec(re->param_data,
                                    rule->actionset->msg, strlen(rule->actionset->msg),
                                    &my_error_msg);
                            if (rc >= 0) {
                                remove_rule = 1;
                            }
                        }

                        break;
                    case RULE_EXCEPTION_REMOVE_TAG :
                        if ((rule->actionset != NULL)&&(apr_is_empty_table(rule->actionset->actions) == 0)) {
                            char *my_error_msg = NULL;
                            const apr_array_header_t *tarr = NULL;
                            const apr_table_entry_t *telts = NULL;
                            int act;

                            tarr = apr_table_elts(rule->actionset->actions);
                            telts = (const apr_table_entry_t*)tarr->elts;

                            for (act = 0; act < tarr->nelts; act++) {
                                msre_action *action = (msre_action *)telts[act].val;
                                if((action != NULL) && (action->metadata != NULL) && (strcmp("tag", action->metadata->name) == 0))  {

                                    int rc = msc_regexec(re->param_data,
                                            action->param, strlen(action->param),
                                            &my_error_msg);
                                    if (rc >= 0)    {
                                        remove_rule = 1;
                                    }
                                }
                            }
                        }
                        break;
                }
            }

            if (remove_rule) {
                /* Do not increment j. */
                removed_count++;
                if (rule->actionset->is_chained) mode = 2; /* Remove rules in this chain. */
            } else {
                if (rule->actionset->is_chained) mode = 1; /* Keep rules in this chain. */
                rules[j++] = rules[i];
            }
        } else { /* Handling rule that is part of a chain. */
            if (mode == 2) { /* We want to remove the rule. */
                /* Do not increment j. */
                removed_count++;
            } else {
                rules[j++] = rules[i];
            }

            if ((rule->actionset == NULL)||(rule->actionset->is_chained == 0)) mode = 0;
        }
    }

    /* Update the number of rules in the array. */
    phase_arr->nelts -= removed_count;

    return 0;
}

/**
 * Removes from the ruleset all rules that match the given exception.
 */
int msre_ruleset_rule_remove_with_exception(msre_ruleset *ruleset, rule_exception *re) {
    int count = 0;

    if (ruleset == NULL) return 0;

    count += msre_ruleset_phase_rule_remove_with_exception(ruleset, re, ruleset->phase_request_headers);
    count += msre_ruleset_phase_rule_remove_with_exception(ruleset, re, ruleset->phase_request_body);
    count += msre_ruleset_phase_rule_remove_with_exception(ruleset, re, ruleset->phase_response_headers);
    count += msre_ruleset_phase_rule_remove_with_exception(ruleset, re, ruleset->phase_response_body);
    count += msre_ruleset_phase_rule_remove_with_exception(ruleset, re, ruleset->phase_logging);

    return count;
}


/* -- Rule functions ------------------------------------------------------- */

/**
 * Returns the name of the supplied severity level.
 */
static const char *msre_format_severity(int severity) {
    if ((severity >= 0)&&(severity <= 7)) {
        return severities[severity];
    }
    else {
        return "(invalid value)";
    }
}

/**
 * Creates a string containing the metadata of the supplied rule.
 */
char *msre_format_metadata(modsec_rec *msr, msre_actionset *actionset) {
    const apr_array_header_t *tarr;
    const apr_table_entry_t *telts;
    char *id = "";
    char *rev = "";
    char *msg = "";
    char *logdata = "";
    char *severity = "";
    char *tags = "";
    char *fn = "";
    int k;

    if (actionset == NULL) return "";

    if ((actionset->rule != NULL) && (actionset->rule->filename != NULL)) {
        fn = apr_psprintf(msr->mp, " [file \"%s\"] [line \"%d\"]",
                actionset->rule->filename, actionset->rule->line_num);
    }
    if (actionset->id != NULL) {
        id = apr_psprintf(msr->mp, " [id \"%s\"]",
                log_escape(msr->mp, actionset->id));
    }
    if (actionset->rev != NULL) {
        rev = apr_psprintf(msr->mp, " [rev \"%s\"]",
                log_escape(msr->mp, actionset->rev));
    }
    if (actionset->msg != NULL) {
        /* Expand variables in the message string. */
        msc_string *var = (msc_string *)apr_pcalloc(msr->mp, sizeof(msc_string));
        var->value = (char *)actionset->msg;
        var->value_len = strlen(actionset->msg);
        expand_macros(msr, var, NULL, msr->mp);

        msg = apr_psprintf(msr->mp, " [msg \"%s\"]",
                log_escape_ex(msr->mp, var->value, var->value_len));
    }
    if (actionset->logdata != NULL) {
        /* Expand variables in the message string. */
        msc_string *var = (msc_string *)apr_pcalloc(msr->mp, sizeof(msc_string));
        var->value = (char *)actionset->logdata;
        var->value_len = strlen(actionset->logdata);
        expand_macros(msr, var, NULL, msr->mp);

        logdata = apr_psprintf(msr->mp, " [data \"%s\"]",
                log_escape_hex(msr->mp, (unsigned char *)var->value, var->value_len));

        /* If it is > 512 bytes, then truncate at 512 with ellipsis.
         * NOTE: 512 actual data + 9 bytes of label = 521
         */
        if (strlen(logdata) > 521) {
            logdata[517] = '.';
            logdata[518] = '.';
            logdata[519] = '.';
            logdata[520] = '"';
            logdata[521] = ']';
            logdata[522] = '\0';
        }
    }
    if ((actionset->severity >= 0)&&(actionset->severity <= 7)) {
        severity = apr_psprintf(msr->mp, " [severity \"%s\"]",
                msre_format_severity(actionset->severity));
    }

    /* Extract rule tags from the action list. */
    tarr = apr_table_elts(actionset->actions);
    telts = (const apr_table_entry_t*)tarr->elts;

    for (k = 0; k < tarr->nelts; k++) {
        msre_action *action = (msre_action *)telts[k].val;
        if (strcmp(telts[k].key, "tag") == 0) {
            /* Expand variables in the tag argument. */
            msc_string *var = (msc_string *)apr_pcalloc(msr->mp, sizeof(msc_string));

            var->value = (char *)action->param;
            var->value_len = strlen(action->param);
            expand_macros(msr, var, NULL, msr->mp);

            tags = apr_psprintf(msr->mp, "%s [tag \"%s\"]", tags,
               log_escape(msr->mp, var->value));
        }
    }

    return apr_pstrcat(msr->mp, fn, id, rev, msg, logdata, severity, tags, NULL);
}

char * msre_rule_generate_unparsed(apr_pool_t *pool,  const msre_rule *rule, const char *targets,
        const char *args, const char *actions)
{
    char *unparsed = NULL;
    const char *r_targets = targets;
    const char *r_args = args;
    const char *r_actions = actions;

    if (r_targets == NULL) {
        r_targets = rule->p1;
    }
    if (r_args == NULL) {
        r_args = apr_pstrcat(pool, (rule->op_negated ? "!" : ""), "@", rule->op_name, " ", rule->op_param, NULL);
    }
    if (r_actions == NULL) {
        r_actions = msre_actionset_generate_action_string(pool, rule->actionset);
    }

    switch (rule->type) {
        case RULE_TYPE_NORMAL:
            if (r_actions == NULL) {
                unparsed = apr_psprintf(pool, "SecRule \"%s\" \"%s\"",
                        log_escape(pool, r_targets), log_escape(pool, r_args));
            }
            else {
                unparsed = apr_psprintf(pool, "SecRule \"%s\" \"%s\" \"%s\"",
                        log_escape(pool, r_targets), log_escape(pool, r_args),
                        log_escape(pool, r_actions));
            }
            break;
        case RULE_TYPE_ACTION:
            unparsed = apr_psprintf(pool, "SecAction \"%s\"",
                    log_escape(pool, r_actions));
            break;
        case RULE_TYPE_MARKER:
            unparsed = apr_psprintf(pool, "SecMarker \"%s\"", rule->actionset->id);
            break;
#if defined(WITH_LUA)
        case RULE_TYPE_LUA:
            /* SecRuleScript */
            if (r_actions == NULL) {
                unparsed = apr_psprintf(pool, "SecRuleScript \"%s\"", r_args);
            }
            else {
                unparsed = apr_psprintf(pool, "SecRuleScript \"%s\" \"%s\"",
                        r_args, log_escape(pool, r_actions));
            }
            break;
#endif
    }

    return unparsed;
}

/**
 * Assembles a new rule using the strings that contain a list
 * of targets (variables), arguments, and actions.
 */
msre_rule *msre_rule_create(msre_ruleset *ruleset, int type,
        const char *fn, int line, const char *targets,
        const char *args, const char *actions, char **error_msg)
{
    msre_rule *rule;
    char *my_error_msg;
    const char *argsp;
    int rc;

    if (error_msg == NULL) return NULL;
    *error_msg = NULL;

    rule = (msre_rule *)apr_pcalloc(ruleset->mp, sizeof(msre_rule));
    if (rule == NULL) return NULL;

    rule->type = type;
    rule->ruleset = ruleset;
    rule->targets = apr_array_make(ruleset->mp, 10, sizeof(const msre_var *));
    rule->p1 = apr_pstrdup(ruleset->mp, targets);
    rule->filename = apr_pstrdup(ruleset->mp, fn);
    rule->line_num = line;

    /* Parse targets */
    rc = msre_parse_targets(ruleset, targets, rule->targets, &my_error_msg);
    if (rc < 0) {
        *error_msg = apr_psprintf(ruleset->mp, "Error creating rule: %s", my_error_msg);
        return NULL;
    }

    /* Parse args */
    argsp = args;

    /* Is negation used? */
    if (*argsp == '!') {
        rule->op_negated = 1;
        argsp++;
        while((isspace(*argsp))&&(*argsp != '\0')) argsp++;
    }

    /* Is the operator explicitly selected? */
    if (*argsp != '@') {
        /* Go with a regular expression. */
        rule->op_name = "rx";
        rule->op_param = argsp;
    } else  {
        /* Explicitly selected operator. */
        char *p = (char *)(argsp + 1);
        while((!isspace(*p))&&(*p != '\0')) p++;
        rule->op_name = apr_pstrmemdup(ruleset->mp, argsp + 1, p - (argsp + 1));
        while(isspace(*p)) p++; /* skip over the whitespace at the end*/
        rule->op_param = p; /* IMP1 So we always have a parameter even when it's empty? */
    }

    /* Find the operator. */
    rule->op_metadata = msre_engine_op_resolve(ruleset->engine, rule->op_name);
    if (rule->op_metadata == NULL) {
        *error_msg = apr_psprintf(ruleset->mp,
                "Error creating rule: Failed to resolve operator: %s", rule->op_name);
        return NULL;
    }

    /* Initialise & validate parameter */
    if (rule->op_metadata->param_init != NULL) {
        if (rule->op_metadata->param_init(rule, &my_error_msg) <= 0) {
            *error_msg = apr_psprintf(ruleset->mp, "Error creating rule: %s", my_error_msg);
            return NULL;
        }
    }

    /* Parse actions */
    if (actions != NULL) {
        /* Create per-rule actionset */
        rule->actionset = msre_actionset_create(ruleset->engine, actions, &my_error_msg);
        if (rule->actionset == NULL) {
            *error_msg = apr_psprintf(ruleset->mp, "Error parsing actions: %s", my_error_msg);
            return NULL;
        }
    }

    /* Add the unparsed rule */
    rule->unparsed = msre_rule_generate_unparsed(ruleset->mp, rule, targets, args, NULL);

    return rule;
}

#if defined(WITH_LUA)
/**
 *
 */
msre_rule *msre_rule_lua_create(msre_ruleset *ruleset,
        const char *fn, int line, const char *script_filename,
        const char *actions, char **error_msg)
{
    msre_rule *rule;
    char *my_error_msg;

    if (error_msg == NULL) return NULL;
    *error_msg = NULL;

    rule = (msre_rule *)apr_pcalloc(ruleset->mp, sizeof(msre_rule));
    if (rule == NULL) return NULL;

    rule->type = RULE_TYPE_LUA;
    rule->ruleset = ruleset;
    rule->filename = apr_pstrdup(ruleset->mp, fn);
    rule->line_num = line;

    /* Compile script. */
    *error_msg = lua_compile(&rule->script, script_filename, ruleset->mp);
    if (*error_msg != NULL) {
        return NULL;
    }

    /* Parse actions */
    if (actions != NULL) {
        /* Create per-rule actionset */
        rule->actionset = msre_actionset_create(ruleset->engine, actions, &my_error_msg);
        if (rule->actionset == NULL) {
            *error_msg = apr_psprintf(ruleset->mp, "Error parsing actions: %s", my_error_msg);
            return NULL;
        }
    }

    /* Add the unparsed rule */
    rule->unparsed = msre_rule_generate_unparsed(ruleset->mp, rule, NULL, script_filename, NULL);

    return rule;
}
#endif

/**
 * Perform non-disruptive actions associated with the provided actionset.
 */
static void msre_perform_nondisruptive_actions(modsec_rec *msr, msre_rule *rule,
        msre_actionset *actionset, apr_pool_t *mptmp)
{
    const apr_array_header_t *tarr;
    const apr_table_entry_t *telts;
    int i;

    tarr = apr_table_elts(actionset->actions);
    telts = (const apr_table_entry_t*)tarr->elts;
    for (i = 0; i < tarr->nelts; i++) {
        msre_action *action = (msre_action *)telts[i].val;
        if (action->metadata->type == ACTION_NON_DISRUPTIVE) {
            if (action->metadata->execute != NULL) {
                action->metadata->execute(msr, mptmp, rule, action);
            }
        }
    }
}

/**
 * Perform the disruptive actions associated with the given actionset.
 */
static void msre_perform_disruptive_actions(modsec_rec *msr, msre_rule *rule,
        msre_actionset *actionset, apr_pool_t *mptmp, const char *message)
{
    const apr_array_header_t *tarr;
    const apr_table_entry_t *telts;
    int i;

    /* Execute the disruptive actions. Do note that this does
     * not mean the request will be interrupted straight away. All
     * disruptive actions need to do here is update the information
     * that will be used to act later.
     */
    tarr = apr_table_elts(actionset->actions);
    telts = (const apr_table_entry_t*)tarr->elts;
    for (i = 0; i < tarr->nelts; i++) {
        msre_action *action = (msre_action *)telts[i].val;
        if (action->metadata->type == ACTION_DISRUPTIVE) {
            if (action->metadata->execute != NULL) {
                action->metadata->execute(msr, mptmp, rule, action);
            }
        }
    }

    /* If "noauditlog" was used do not mark the transaction relevant. */
    if (actionset->auditlog != 0) {
        msr->is_relevant++;
    }

    /* We only do stuff when in ONLINE mode. In all other
     * cases we only emit warnings.
     */
    if ((msr->phase == PHASE_LOGGING)
            || (msr->txcfg->is_enabled == MODSEC_DETECTION_ONLY)
            || (msr->modsecurity->processing_mode == MODSEC_OFFLINE)
            || (actionset->intercept_action == ACTION_NONE))
    {
        int log_level;

        /* If "nolog" was used log at a higher level to prevent an "alert". */
        if (actionset->log == 0) {
            log_level = 4;

            /* But, if "auditlog" is enabled, then still add the message. */
            if (actionset->auditlog != 0) {
                *(const char **)apr_array_push(msr->alerts) = msc_alert_message(msr, actionset, NULL, message);
            }

        }
        else {
            log_level = 2;
        }

        msc_alert(msr, log_level, actionset, "Warning.", message);

        /* However, this will mark the txn relevant again if it is <= 3,
         * which will mess up noauditlog.  We need to compensate for this
         * so that we do not increment twice when auditlog is enabled and
         * prevent incrementing when auditlog is disabled.
         */
        if (log_level <= 3) {
            msr->is_relevant--;
        }

        return;
    }

    /* Signal to the engine we need to intercept this
     * transaction, and rememer the rule that caused it.
     */
    msr->was_intercepted = 1;
    msr->rule_was_intercepted = 1;
    msr->intercept_phase = msr->phase;
    msr->intercept_actionset = actionset;
    msr->intercept_message = message;
}

/**
 * Invokes the rule operator against the given value.
 */
static int execute_operator(msre_var *var, msre_rule *rule, modsec_rec *msr,
    msre_actionset *acting_actionset, apr_pool_t *mptmp)
{
    apr_time_t time_before_op = 0;
    char *my_error_msg = NULL;
    const char *full_varname = NULL;
    char *parm = NULL;
    int rc;

    /* determine the full var name if not already resolved
     *
     * NOTE: this can happen if the var does not match but it is
     * being tested for non-existance as in:
     *   @REQUEST_HEADERS:Foo "@eq 0"
     *   @REQUEST_HEADERS:Foo "!@eq 1"
     */
    if ((var->param != NULL) && (var->name != NULL) && (strchr(var->name,':') == NULL)) {
        full_varname = apr_psprintf(mptmp, "%s%s:%s",
                                    (var->is_counting ? "&" : ""),
                                    var->name, var->param);
    }
    else if ((var->name != NULL) && var->is_counting && (*var->name != '&')) {
        full_varname = apr_pstrcat(mptmp, "&", var->name, NULL);
    }
    else {
        full_varname = var->name;
    }

    if (msr->txcfg->debuglog_level >= 4) {
        msr_log(msr, 4, "Executing operator \"%s%s\" with param \"%s\" against %s.",
            (rule->op_negated ? "!" : ""), rule->op_name,
            log_escape(msr->mp, rule->op_param), full_varname);
    }

    if (msr->txcfg->debuglog_level >= 9) {
        msr_log(msr, 9, "Target value: \"%s\"", log_escape_nq_ex(msr->mp, var->value,
            var->value_len));
    }

    #if defined(PERFORMANCE_MEASUREMENT)
    time_before_op = apr_time_now();
    #else
    if (msr->txcfg->debuglog_level >= 4) {
        time_before_op = apr_time_now();
    }
    #endif

    rc = rule->op_metadata->execute(msr, rule, var, &my_error_msg);

    #if defined(PERFORMANCE_MEASUREMENT)
    {
        /* Record performance but do not log anything. */
        apr_time_t t1 = apr_time_now();
        rule->op_time += (t1 - time_before_op);
    }
    #else
    if (msr->txcfg->debuglog_level >= 4) {
        apr_time_t t1 = apr_time_now();
        msr_log(msr, 4, "Operator completed in %" APR_TIME_T_FMT " usec.", (t1 - time_before_op));
    }
    #endif

    if (rc < 0) {
        msr_log(msr, 4, "Operator error: %s", my_error_msg);
        return -1;
    }

    if (((rc == 0)&&(rule->op_negated == 0))||((rc == 1)&&(rule->op_negated == 1))) {
        /* No match, do nothing. */
        return RULE_NO_MATCH;
    }
    else {
        /* Match. */
        if (rc == 0) {
            char *op_param = log_escape(msr->mp, rule->op_param);

            /* Truncate op parameter. */
            if (strlen(op_param) > 252) {
                op_param = apr_psprintf(msr->mp, "%.252s ...", op_param);
            }

            /* Operator did not match so we need to provide a message. */
            my_error_msg = apr_psprintf(msr->mp, "Match of \"%s %s\" against \"%s\" required.",
                log_escape(msr->mp, rule->op_name), op_param,
                log_escape(msr->mp, full_varname));
        }

        /* Save the rules that match */
        *(const msre_rule **)apr_array_push(msr->matched_rules) = rule;

        /* Save the last matched var data */
        msr->matched_var->name = apr_pstrdup(msr->mp, var->name);
        msr->matched_var->name_len = strlen(msr->matched_var->name);
        msr->matched_var->value = apr_pmemdup(msr->mp, var->value, var->value_len);
        msr->matched_var->value_len = var->value_len;

        parm = strchr(msr->matched_var->name,':');

        if(parm)    {
            msc_string *mvar = NULL;

            parm++;

            mvar = apr_palloc(msr->mp, sizeof(msc_string));
            mvar->name = apr_pstrdup(msr->mp, parm);
            mvar->name_len = strlen(mvar->name);
            mvar->value = apr_pmemdup(msr->mp, var->value, var->value_len);
            mvar->value_len = var->value_len;

            apr_table_unset(msr->matched_vars, parm);
            apr_table_setn(msr->matched_vars, parm, (void *)mvar);

        } else {

            msc_string *mvar = apr_palloc(msr->mp, sizeof(msc_string));
            mvar->name = apr_pstrdup(msr->mp, var->name);
            mvar->name_len = strlen(mvar->name);
            mvar->value = apr_pmemdup(msr->mp, var->value, var->value_len);
            mvar->value_len = var->value_len;

            apr_table_unset(msr->matched_vars, mvar->name);
            apr_table_setn(msr->matched_vars, mvar->name, (void *)mvar);
        }

        /* Keep track of the highest severity matched so far */
        if ((acting_actionset->severity > 0) && (acting_actionset->severity < msr->highest_severity))
        {
            msr->highest_severity = acting_actionset->severity;
        }


        /* Perform non-disruptive actions. */
        msre_perform_nondisruptive_actions(msr, rule, rule->actionset, mptmp);

        /* Perform disruptive actions, but only if
         * this rule is not part of a chain.
         */
        if (rule->actionset->is_chained == 0) {
            msre_perform_disruptive_actions(msr, rule, acting_actionset, mptmp, my_error_msg);
        }

        return RULE_MATCH;
    }
}

/**
 * Executes rule against the given transaction.
 */
static apr_status_t msre_rule_process_normal(msre_rule *rule, modsec_rec *msr) {
    const apr_array_header_t *arr = NULL;
    const apr_table_entry_t *te = NULL;
    msre_actionset *acting_actionset = NULL;
    msre_var **targets = NULL;
    apr_pool_t *mptmp = msr->msc_rule_mptmp;
    apr_table_t *tartab = NULL;
    apr_table_t *vartab = NULL;
    int i, rc = 0, match_count = 0;
    int invocations = 0;
    int multi_match = 0;

    /* Choose the correct metadata/disruptive action actionset. */
    acting_actionset = rule->actionset;
    if (rule->chain_starter != NULL) {
        acting_actionset = rule->chain_starter->actionset;
    }

    /* Configure recursive matching. */
    if (apr_table_get(rule->actionset->actions, "multiMatch") != NULL) {
        multi_match = 1;
    }

    /* ENH: What is a good initial size? */
    tartab = apr_table_make(mptmp, 24);
    if (tartab == NULL) return -1;
    vartab = apr_table_make(mptmp, 24);
    if (vartab == NULL) return -1;

    /* Expand variables to create a list of targets. */

    targets = (msre_var **)rule->targets->elts;
    for (i = 0; i < rule->targets->nelts; i++) {
        int j, list_count;

        apr_table_clear(vartab);

        /* ENH Introduce a new variable hook that would allow the code
         *     behind the variable to return the size of the collection
         *     without having to generate the variables.
         */

        /* Expand individual variables first. */
        list_count = targets[i]->metadata->generate(msr, targets[i], rule, vartab, mptmp);

        if (targets[i]->is_counting) {
            /* Count how many there are and just add the score to the target list. */
            msre_var *newvar = (msre_var *)apr_pmemdup(mptmp, targets[i], sizeof(msre_var));
            newvar->value = apr_psprintf(mptmp, "%d", list_count);
            newvar->value_len = strlen(newvar->value);
            apr_table_addn(tartab, newvar->name, (void *)newvar);
        } else {
            /* And either add them or remove from the final target list. */
            arr = apr_table_elts(vartab);
            te = (apr_table_entry_t *)arr->elts;
            for(j = 0; j < arr->nelts; j++) {
                if (targets[i]->is_negated == 0) {
                    apr_table_addn(tartab, te[j].key, te[j].val);
                } else {
                    apr_table_unset(tartab, te[j].key);
                }
            }
        }
    }

    /* Log the target variable expansion */
    if (msr->txcfg->debuglog_level >= 4) {
        const char *expnames = NULL;

        arr = apr_table_elts(tartab);
        if (arr->nelts > 1) {
            te = (apr_table_entry_t *)arr->elts;
            expnames = apr_pstrdup(mptmp, ((msre_var *)te[0].val)->name);
            for(i = 1; i < arr->nelts; i++) {
                expnames = apr_psprintf(mptmp, "%s|%s", expnames, ((msre_var *)te[i].val)->name);
            }
            if (strcmp(rule->p1, expnames) != 0) {
                msr_log(msr, 4, "Expanded \"%s\" to \"%s\".", rule->p1, expnames);
            }
        }
    }

    /* Loop through targets on the final target list,
     * perform transformations as necessary, and invoke
     * the operator.
     */

    arr = apr_table_elts(tartab);
    te = (apr_table_entry_t *)arr->elts;
    for (i = 0; i < arr->nelts; i++) {
        int changed;
        int usecache = 0;
        apr_table_t *cachetab = NULL;
        apr_time_t time_before_trans = 0;
        msre_var *var;

        /* Take one target. */
        var = (msre_var *)te[i].val;

        /* Is this var cacheable? */
        if (msr->txcfg->cache_trans != MODSEC_CACHE_DISABLED) {
            usecache = 1;

            /* Counting vars are not cacheable due to them being created
             * in a local per-rule pool.
             */
            if (var->is_counting) {
                if (msr->txcfg->debuglog_level >= 9) {
                    msr_log(msr, 9, "CACHE: Disabled - &%s is dynamic", var->name);
                }

                usecache = 0;
            }
            /* Only cache if if the variable is available in this phase */
            else if (msr->phase < var->metadata->availability) {
                if (msr->txcfg->debuglog_level >= 9) {
                    msr_log(msr, 9, "CACHE: Disabled - %s is not yet available in phase %d (requires phase %d or later)", var->name, msr->phase, var->metadata->availability);
                }

                usecache = 0;
            }
            /* check the cache options */
            else if (var->value_len < msr->txcfg->cache_trans_min) {
                if (msr->txcfg->debuglog_level >= 9) {
                    msr_log(msr, 9, "CACHE: Disabled - %s value length=%u, smaller than minlen=%" APR_SIZE_T_FMT, var->name, var->value_len, msr->txcfg->cache_trans_min);
                }

                usecache = 0;
            }
            else if ((msr->txcfg->cache_trans_max != 0) && (var->value_len > msr->txcfg->cache_trans_max)) {
                if (msr->txcfg->debuglog_level >= 9) {
                    msr_log(msr, 9, "CACHE: Disabled - %s value length=%u, larger than maxlen=%" APR_SIZE_T_FMT, var->name, var->value_len, msr->txcfg->cache_trans_max);
                }

                usecache = 0;
            }

            /* if cache is still enabled, check the VAR for cacheablity */
            if (usecache) {
                if (var->metadata->is_cacheable == VAR_CACHE) {
                    if (msr->txcfg->debuglog_level >= 9) {
                        msr_log(msr, 9, "CACHE: Enabled");
                    }

                    #ifdef CACHE_DEBUG
                    msr_log(msr, 9, "CACHE: Fetching cache entry from hash=%pp: %pp=%s", msr->tcache, var, var->name);
                    #endif

                    /* Fetch cache table for this target */
                    cachetab = (apr_table_t *)apr_hash_get(msr->tcache, var->value, sizeof(var->value));

                    /* Create an empty cache table if this is the first time */
                    #ifdef CACHE_DEBUG
                    if (cachetab) {
                        msr_log(msr, 9, "CACHE: Using cache table %pp", cachetab);
                    }
                    else
                    #else
                    if (cachetab == NULL)
                    #endif
                    {
                        /* NOTE: We use the pointer to the var value as a hash
                         *       key as it is unique. This pointer *must*
                         *       remain valid through the entire phase. If
                         *       it does not, then we will not receive a cache
                         *       hit and just wasted RAM. So, it is important
                         *       that any such vars be marked as VAR_DONT_CACHE.
                         *
                         * ENH: Only use pointer for non-scalar vars
                         */
                        cachetab = apr_table_make(msr->mp, 3);
                        apr_hash_set(msr->tcache, var->value, sizeof(var->value), cachetab);

                        #ifdef CACHE_DEBUG
                        msr_log(msr, 9, "CACHE: Created a new cache table %pp for %pp", cachetab, var->value);
                        #endif
                    }

                }
                else {
                    usecache = 0;

                    if (msr->txcfg->debuglog_level >= 9) {
                        msr_log(msr, 9, "CACHE: %s transformations are not cacheable", var->name);
                    }
                }
            }
        }

        #if defined(PERFORMANCE_MEASUREMENT)
        time_before_trans = apr_time_now();
        #else
        if (msr->txcfg->debuglog_level >= 4) {
            time_before_trans = apr_time_now();
        }
        #endif

        /* Transform target. */
        {
            const apr_array_header_t *tarr;
            const apr_table_entry_t *telts;
            const char *tfnspath = NULL;
            char *tfnskey = NULL;
            int tfnscount = 0;
            int last_cached_tfn = 0;
            msre_cache_rec *crec = NULL;
            msre_cache_rec *last_crec = NULL;
            int k;
            msre_action *action;
            msre_tfn_metadata *metadata;
            apr_table_t *normtab;
            const char *lastvarval = NULL;
            apr_size_t lastvarlen = 0;
            int tfnchanged = 0;

            changed = 0;
            normtab = apr_table_make(mptmp, 10);
            if (normtab == NULL) return -1;
            tarr = apr_table_elts(rule->actionset->actions);
            telts = (const apr_table_entry_t*)tarr->elts;

            /* Build the final list of transformation functions. */
            for (k = 0; k < tarr->nelts; k++) {
                action = (msre_action *)telts[k].val;

                if (strcmp(telts[k].key, "t") == 0) {
                    if (strcmp(action->param, "none") == 0) {
                        apr_table_clear(normtab);
                        tfnspath = NULL;
                        tfnskey = NULL;
                        tfnscount = 0;
                        last_crec = NULL;
                        last_cached_tfn = 0;
                        continue;
                    }

                    if (action->param_plusminus == NEGATIVE_VALUE) {
                        apr_table_unset(normtab, action->param);
                    }
                    else {
                        tfnscount++;

                        apr_table_addn(normtab, action->param, (void *)action);

                        /* Check the cache, saving the 'most complete' as a
                         * starting point
                         */
                        if (usecache) {
                            tfnspath = apr_psprintf(mptmp, "%s%s%s", (tfnspath?tfnspath:""), (tfnspath?",":""), action->param);
                            tfnskey = apr_psprintf(mptmp, "%x;%s", tfnscount, tfnspath);
                            crec = (msre_cache_rec *)apr_table_get(cachetab, tfnskey);

                            #ifdef CACHE_DEBUG
                            msr_log(msr, 9, "CACHE: %s %s cached=%d", var->name, tfnskey, (crec ? 1 : 0));
                            #endif

                            if (crec != NULL) {
                                last_crec = crec;
                                last_cached_tfn = tfnscount;
                            }
                        }
                    }
                }
            }

            /* If the last cached tfn is the last in the list
             * then we can stop here and just execute the action immediatly
             */
            if (usecache && !multi_match &&
                (crec != NULL) && (crec == last_crec))
            {
                crec->hits++;

                if (crec->changed) {
                    var->value = apr_pmemdup(mptmp, crec->val, crec->val_len);
                    var->value_len = crec->val_len;
                }

                if (msr->txcfg->debuglog_level >= 9) {
                    msr_log(msr, 9, "T (%d) %s: \"%s\" [fully cached hits=%d]", crec->changed, crec->path,
                        log_escape_nq_ex(mptmp, var->value, var->value_len), crec->hits);
                }

                #if defined(PERFORMANCE_MEASUREMENT) 
                {
                    apr_time_t t1 = apr_time_now();
                    rule->trans_time += (t1 - time_before_trans);
                }
                #else
                if (msr->txcfg->debuglog_level >= 4) {
                    apr_time_t t1 = apr_time_now();

                    msr_log(msr, 4, "Transformation completed in %" APR_TIME_T_FMT " usec.",
                        (t1 - time_before_trans));
                }
                #endif

                rc = execute_operator(var, rule, msr, acting_actionset, mptmp);

                if (rc < 0) {
                    return -1;
                }

                if (rc == RULE_MATCH) {
                    match_count++;

                    /* Return straight away if the transaction
                     * was intercepted - no need to process the remaining
                     * targets.
                     */
                    if (msr->rule_was_intercepted) {
                        return RULE_MATCH;
                    }
                }

                continue; /* next target */
            }


            /* Perform transformations. */

            tarr = apr_table_elts(normtab);

            /* Execute transformations in a loop. */

            /* Start after the last known cached transformation if we can */
            if (!multi_match && (last_crec != NULL)) {
                k = last_cached_tfn;
                tfnspath = last_crec->path;
                last_crec->hits++;

                if ((changed = last_crec->changed) > 0) {
                    var->value = last_crec->val;
                    var->value_len = last_crec->val_len;
                }

                if (msr->txcfg->debuglog_level >= 9) {
                    msr_log(msr, 9, "T (%d) %s: \"%s\" [partially cached hits=%d]", last_crec->changed,
                        tfnspath, log_escape_nq_ex(mptmp, var->value, var->value_len), last_crec->hits);
                }
            }
            else {
                tfnspath = NULL;
                k = 0;
            }

            /* Make a copy of the value so that we can change it in-place. */
            if (tarr->nelts) {
                var->value = apr_pstrmemdup(mptmp, var->value, var->value_len);
                /* var->value_len remains the same */
            }

            telts = (const apr_table_entry_t*)tarr->elts;
            for (; k < tarr->nelts; k++) {
                char *rval = NULL;
                long int rval_length = -1;

                /* In multi-match mode we execute the operator
                 * once at the beginning and then once every
                 * time the variable is changed by the transformation
                 * function.
                 */
                if (multi_match && (k == 0 || tfnchanged)) {
                    invocations++;

                    #if defined(PERFORMANCE_MEASUREMENT)
                    {
                        apr_time_t t1 = apr_time_now();
                        rule->trans_time += (t1 - time_before_trans);
                    }
                    #else
                    if (msr->txcfg->debuglog_level >= 4) {
                        apr_time_t t1 = apr_time_now();

                        msr_log(msr, 4, "Transformation completed in %" APR_TIME_T_FMT " usec.",
                            (t1 - time_before_trans));
                    }
                    #endif

                    rc = execute_operator(var, rule, msr, acting_actionset, mptmp);

                    if (rc < 0) {
                        return -1;
                    }

                    if (rc == RULE_MATCH) {
                        match_count++;

                        /* Return straight away if the transaction
                        * was intercepted - no need to process the remaining
                        * targets.
                        */
                        if (msr->rule_was_intercepted) {
                            return RULE_MATCH;
                        }
                    }
                }

                /* Perform one transformation. */
                action = (msre_action *)telts[k].val;
                metadata = (msre_tfn_metadata *)action->param_data;
                tfnchanged = metadata->execute(mptmp,
                    (unsigned char *)var->value, var->value_len,
                    &rval, &rval_length);

                if (tfnchanged < 0) {
                    return -1;
                }

                if (tfnchanged) {
                    changed++;
                }

                /* Use the new values */
                var->value = rval;
                var->value_len = rval_length;

                /* Cache the transformation */
                if (usecache) {
                    int tfnsnum = k + 1;

                    /* Generate the cache key */
                    tfnspath = apr_psprintf(msr->mp, "%s%s%s", (tfnspath ? tfnspath : ""),
                        (tfnspath ? "," : ""), action->param);
                    tfnskey = apr_psprintf(msr->mp, "%x;%s", tfnsnum, tfnspath);

                    if ((msr->txcfg->cache_trans_maxitems != 0) &&
                        (msr->tcache_items >= msr->txcfg->cache_trans_maxitems))
                    {
                        /* Warn only once if we attempt to go over the cache limit. */
                        if (msr->tcache_items == msr->txcfg->cache_trans_maxitems) {
                            msr->tcache_items++;
                            msr_log(msr, 4, "CACHE: Disabled - phase=%d"
                                            " maxitems=%" APR_SIZE_T_FMT
                                            " limit reached.",
                                            msr->phase,
                                            msr->txcfg->cache_trans_maxitems);
                        }
                    }
                    else if (msr->txcfg->cache_trans_incremental ||
                        (tfnsnum == tarr->nelts))
                    {
                        /* ENH1: Add flag to vars to tell which ones can change across phases store the rest in a global cache */
                        crec = (msre_cache_rec *)apr_pcalloc(msr->mp, sizeof(msre_cache_rec));
                        if (crec == NULL) return -1;

                        crec->hits = 0;
                        crec->changed = changed;
                        crec->num = k + 1;
                        crec->path = tfnspath;

                        /* We want to cache a copy if it changed otherwise
                         * we just want to use a pointer to the last changed value.
                         */
                        crec->val = (!lastvarval || tfnchanged) ? apr_pmemdup(msr->mp, var->value, var->value_len) : lastvarval;
                        crec->val_len = changed ? ((!lastvarval || tfnchanged) ? var->value_len : lastvarlen) : 0;

                        /* Keep track of the last changed var value */
                        if (tfnchanged) {
                            lastvarval = crec->val;
                            lastvarlen = crec->val_len;
                        }

                        #ifdef CACHE_DEBUG
                        if (changed) {
                            msr_log(msr, 9, "CACHE: Caching %s=\"%s\" (%pp)",
                                            tfnskey,
                                            log_escape_nq_ex(mptmp,
                                                             crec->val,
                                                             crec->val_len),
                                            var);
                        }
                        else {
                            msr_log(msr, 9, "CACHE: Caching %s=<no change> (%pp)",
                                            tfnskey,
                                            var);
                        }
                        #endif

                        msr->tcache_items++;

                        apr_table_setn(cachetab, tfnskey, (void *)crec);
                    }
                }

                if (msr->txcfg->debuglog_level >= 9) {
                    msr_log(msr, 9, "T (%d) %s: \"%s\"", rc, metadata->name,
                        log_escape_nq_ex(mptmp, var->value, var->value_len));
                }
            }
        }

        /* Execute operator if multi-matching is not enabled,
         * or if it is and we need to process the result of the
         * last transformation.
         */
        if (!multi_match || changed) {
            invocations++;

            #if defined(PERFORMANCE_MEASUREMENT)
            {
                apr_time_t t1 = apr_time_now();
                rule->trans_time += (t1 - time_before_trans);
            }
            #else
            if (msr->txcfg->debuglog_level >= 4) {
                apr_time_t t1 = apr_time_now();

                msr_log(msr, 4, "Transformation completed in %" APR_TIME_T_FMT " usec.",
                    (t1 - time_before_trans));
            }
            #endif

            rc = execute_operator(var, rule, msr, acting_actionset, mptmp);

            if (rc < 0) {
                return -1;
            }

            if (rc == RULE_MATCH) {
                match_count++;

                /* Return straight away if the transaction
                 * was intercepted - no need to process the remaining
                 * targets.
                 */
                if (msr->rule_was_intercepted) {
                    return RULE_MATCH;
                }
            }
        }
    }


    return (match_count ? RULE_MATCH : RULE_NO_MATCH);
}

#if defined(WITH_LUA)
/**
 *
 */
static apr_status_t msre_rule_process_lua(msre_rule *rule, modsec_rec *msr) {
    msre_actionset *acting_actionset = NULL;
    char *my_error_msg = NULL;
    int rc;

    /* Choose the correct metadata/disruptive action actionset. */
    acting_actionset = rule->actionset;
    if (rule->chain_starter != NULL) {
        acting_actionset = rule->chain_starter->actionset;
    }

    rc = lua_execute(rule->script, NULL, msr, rule, &my_error_msg);
    if (rc < 0) {
        msr_log(msr, 1, "%s", my_error_msg);
        return -1;
    }

    /* A non-NULL error message means the rule matched. */
    if (my_error_msg != NULL) {
        /* Perform non-disruptive actions. */
        msre_perform_nondisruptive_actions(msr, rule, rule->actionset, msr->msc_rule_mptmp);

        /* Perform disruptive actions, but only if
         * this rule is not part of a chain.
         */
        if (rule->actionset->is_chained == 0) {
            msre_perform_disruptive_actions(msr, rule, acting_actionset, msr->msc_rule_mptmp, my_error_msg);
        }
    }

    return rc;
}
#endif

/**
 *
 */
apr_status_t msre_rule_process(msre_rule *rule, modsec_rec *msr) {
    /* Use a fresh memory sub-pool for processing each rule */
    if (msr->msc_rule_mptmp == NULL) {
        if (apr_pool_create(&msr->msc_rule_mptmp, msr->mp) != APR_SUCCESS) {
            return -1;
        }
    } else {
        apr_pool_clear(msr->msc_rule_mptmp);
    }

    #if defined(WITH_LUA)
    if (rule->type == RULE_TYPE_LUA) {
        return msre_rule_process_lua(rule, msr);
    }
    #endif

    return msre_rule_process_normal(rule, msr);
}

/**
 * Checks whether the given rule ID is in the given range.
 */
int rule_id_in_range(int ruleid, const char *range) {
    char *p = NULL, *saveptr = NULL;
    char *data = NULL;

    if (range == NULL) return 0;
    data = strdup(range);
    if (data == NULL) return 0;

    p = apr_strtok(data, ",", &saveptr);
    while(p != NULL) {
        char *s = strstr(p, "-");
        if (s == NULL) {
            if (ruleid == atoi(p)) {
                free(data);
                return 1;
            }
        } else {
            int start = atoi(p);
            int end = atoi(s + 1);
            if ((ruleid >= start)&&(ruleid <= end)) {
                free(data);
                return 1;
            }
        }
        p = apr_strtok(NULL, ",", &saveptr);
    }

    free(data);

    return 0;
}
