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/* Copyright (C) 2007-2010 Open Information Security Foundation
*
* You can copy, redistribute or modify this Program under the terms of
* the GNU General Public License version 2 as published by the Free
* Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* version 2 along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*/
/**
* \file
*
* \author Victor Julien <victor@inliniac.net>
* \author Anoop Saldanha <anoopsaldanha@gmail.com>
*
* Implements the priority keyword
*/
#include "suricata-common.h"
#include "detect.h"
#include "detect-parse.h"
#include "detect-engine.h"
#include "detect-engine-mpm.h"
#include "util-error.h"
#include "util-debug.h"
#include "util-unittest.h"
#define DETECT_PRIORITY_REGEX "^\\s*(\\d+|\"\\d+\")\\s*$"
static pcre *regex = NULL;
static pcre_extra *regex_study = NULL;
static int DetectPrioritySetup (DetectEngineCtx *, Signature *, char *);
void SCPriorityRegisterTests(void);
/**
* \brief Registers the handler functions for the "priority" keyword
*/
void DetectPriorityRegister (void)
{
const char *eb = NULL;
int eo;
int opts = 0;
sigmatch_table[DETECT_PRIORITY].name = "priority";
sigmatch_table[DETECT_PRIORITY].desc = "rules with a higher priority will be examined first";
sigmatch_table[DETECT_PRIORITY].url = "https://redmine.openinfosecfoundation.org/projects/suricata/wiki/Meta-settings#Priority";
sigmatch_table[DETECT_PRIORITY].Match = NULL;
sigmatch_table[DETECT_PRIORITY].Setup = DetectPrioritySetup;
sigmatch_table[DETECT_PRIORITY].Free = NULL;
sigmatch_table[DETECT_PRIORITY].RegisterTests = SCPriorityRegisterTests;
regex = pcre_compile(DETECT_PRIORITY_REGEX, opts, &eb, &eo, NULL);
if (regex == NULL) {
SCLogError(SC_ERR_PCRE_COMPILE, "Compile of \"%s\" failed at offset %" PRId32 ": %s",
DETECT_PRIORITY_REGEX, eo, eb);
goto end;
}
regex_study = pcre_study(regex, 0, &eb);
if (eb != NULL) {
SCLogError(SC_ERR_PCRE_STUDY, "pcre study failed: %s", eb);
goto end;
}
end:
return;
}
static int DetectPrioritySetup (DetectEngineCtx *de_ctx, Signature *s, char *rawstr)
{
char copy_str[128] = "";
#define MAX_SUBSTRINGS 30
int ret = 0;
int ov[MAX_SUBSTRINGS];
ret = pcre_exec(regex, regex_study, rawstr, strlen(rawstr), 0, 0, ov, 30);
if (ret < 0) {
SCLogError(SC_ERR_PCRE_MATCH, "Invalid Priority in Signature "
"- %s", rawstr);
return -1;
}
ret = pcre_copy_substring((char *)rawstr, ov, 30, 1, copy_str, sizeof(copy_str));
if (ret < 0) {
SCLogError(SC_ERR_PCRE_GET_SUBSTRING, "pcre_copy_substring failed");
return -1;
}
long prio = 0;
char *endptr = NULL;
prio = strtol(copy_str, &endptr, 10);
if (endptr == NULL || *endptr != '\0') {
SCLogError(SC_ERR_INVALID_SIGNATURE, "Saw an invalid character as arg "
"to priority keyword");
return -1;
}
/* if we have reached here, we have had a valid priority. Assign it */
s->prio = prio;
return 0;
}
/*------------------------------Unittests-------------------------------------*/
#ifdef UNITTESTS
int DetectPriorityTest01()
{
int result = 0;
DetectEngineCtx *de_ctx = DetectEngineCtxInit();
if (de_ctx == NULL) {
goto end;
}
de_ctx->sig_list = SigInit(de_ctx, "alert tcp any any -> any any "
"(msg:\"Priority test\"; priority:2; sid:1;)");
if (de_ctx->sig_list != NULL)
result = 1;
DetectEngineCtxFree(de_ctx);
end:
return result;
}
int DetectPriorityTest02()
{
int result = 0;
Signature *last = NULL;
Signature *sig = NULL;
DetectEngineCtx *de_ctx = DetectEngineCtxInit();
if (de_ctx == NULL) {
goto end;
}
sig = SigInit(de_ctx, "alert tcp any any -> any any "
"(msg:\"Priority test\"; priority:1; sid:1;)");
de_ctx->sig_list = last = sig;
if (sig == NULL) {
result = 0;
} else {
result = 1;
result &= (sig->prio == 1);
}
sig = SigInit(de_ctx, "alert tcp any any -> any any "
"(msg:\"Priority test\"; priority:boo; sid:1;)");
if (last != NULL)
last->next = sig;
result &= (sig == NULL);
sig = SigInit(de_ctx, "alert tcp any any -> any any "
"(msg:\"Priority test\"; priority:10boo; sid:1;)");
if (last != NULL)
last->next = sig;
result &= (sig == NULL);
sig = SigInit(de_ctx, "alert tcp any any -> any any "
"(msg:\"Priority test\"; priority:b10oo; sid:1;)");
if (last != NULL)
last->next = sig;
result &= (sig == NULL);
sig = SigInit(de_ctx, "alert tcp any any -> any any "
"(msg:\"Priority test\"; priority:boo10; sid:1;)");
if (last != NULL)
last->next = sig;
result &= (sig == NULL);
sig = SigInit(de_ctx, "alert tcp any any -> any any "
"(msg:\"Priority test\"; priority:-1; sid:1;)");
if (last != NULL)
last->next = sig;
result &= (sig == NULL);
sig = SigInit(de_ctx, "alert tcp any any -> any any "
"(msg:\"Priority test\"; sid:1;)");
if (last != NULL)
last->next = sig;
if (sig == NULL) {
result &= 0;
} else {
result &= (sig->prio == 3);
}
SigCleanSignatures(de_ctx);
DetectEngineCtxFree(de_ctx);
end:
return result;
}
#endif /* UNITTESTS */
/**
* \brief This function registers unit tests for Classification Config API.
*/
void SCPriorityRegisterTests(void)
{
#ifdef UNITTESTS
UtRegisterTest("DetectPriorityTest01", DetectPriorityTest01, 1);
UtRegisterTest("DetectPriorityTest02", DetectPriorityTest02, 1);
#endif /* UNITTESTS */
}
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