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/* Copyright (C) 2016 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 Giuseppe Longo <glongo@stamus-networks.com>
*
*/
#include "suricata-common.h"
#include "threads.h"
#include "app-layer.h"
#include "app-layer-parser.h"
#include "debug.h"
#include "decode.h"
#include "detect.h"
#include "detect-parse.h"
#include "detect-engine.h"
#include "detect-engine-mpm.h"
#include "detect-engine-state.h"
#include "detect-engine-sigorder.h"
#include "flow.h"
#include "flow-var.h"
#include "flow-util.h"
#include "stream-tcp.h"
#include "util-debug.h"
#include "util-spm-bm.h"
#include "util-unittest.h"
#include "util-unittest-helper.h"
#include "util-device.h"
int DetectBypassMatch(ThreadVars *, DetectEngineThreadCtx *, Packet *, Signature *, const SigMatchCtx *);
static int DetectBypassSetup(DetectEngineCtx *, Signature *, char *);
static void DetectBypassRegisterTests(void);
/**
* \brief Registration function for keyword: bypass
*/
void DetectBypassRegister(void)
{
sigmatch_table[DETECT_BYPASS].name = "bypass";
sigmatch_table[DETECT_BYPASS].desc = "call the bypass callback when the match of a sig is complete";
sigmatch_table[DETECT_BYPASS].url = "";
sigmatch_table[DETECT_BYPASS].Match = DetectBypassMatch;
sigmatch_table[DETECT_BYPASS].AppLayerMatch = NULL;
sigmatch_table[DETECT_BYPASS].Setup = DetectBypassSetup;
sigmatch_table[DETECT_BYPASS].Free = NULL;
sigmatch_table[DETECT_BYPASS].RegisterTests = DetectBypassRegisterTests;
sigmatch_table[DETECT_BYPASS].flags = SIGMATCH_NOOPT;
}
static int DetectBypassSetup(DetectEngineCtx *de_ctx, Signature *s, char *str)
{
SigMatch *sm = NULL;
if (s->flags & SIG_FLAG_FILESTORE) {
SCLogError(SC_ERR_CONFLICTING_RULE_KEYWORDS,
"bypass can't work with filestore keyword");
return -1;
}
s->flags |= SIG_FLAG_BYPASS;
sm = SigMatchAlloc();
if (sm == NULL)
return -1;
sm->type = DETECT_BYPASS;
sm->ctx = NULL;
SigMatchAppendSMToList(s, sm, DETECT_SM_LIST_POSTMATCH);
return 0;
}
int DetectBypassMatch(ThreadVars *tv, DetectEngineThreadCtx *det_ctx, Packet *p, Signature *s, const SigMatchCtx *ctx)
{
PacketBypassCallback(p);
return 1;
}
#ifdef UNITTESTS
static int callback_var = 0;
static int BypassCallback()
{
callback_var = 1;
return 1;
}
static void ResetCallbackVar()
{
callback_var = 0;
}
static int DetectBypassTestSig01(void)
{
TcpSession ssn;
Packet *p1 = NULL;
Packet *p2 = NULL;
ThreadVars th_v;
DetectEngineCtx *de_ctx = NULL;
DetectEngineThreadCtx *det_ctx = NULL;
HtpState *http_state = NULL;
Flow f;
uint8_t http_buf1[] =
"GET /index.html HTTP/1.0\r\n"
"Host: This is dummy message body\r\n"
"User-Agent: www.openinfosecfoundation.org\r\n"
"Content-Type: text/html\r\n"
"\r\n";
uint32_t http_len1 = sizeof(http_buf1) - 1;
uint8_t http_buf2[] =
"HTTP/1.0 200 ok\r\n"
"Content-Type: text/html\r\n"
"Content-Length: 7\r\n"
"\r\n"
"message";
uint32_t http_len2 = sizeof(http_buf2) - 1;
AppLayerParserThreadCtx *alp_tctx = AppLayerParserThreadCtxAlloc();
LiveDevice *livedev = SCMalloc(sizeof(LiveDevice));
FAIL_IF(livedev == NULL);
memset(&th_v, 0, sizeof(th_v));
memset(&f, 0, sizeof(f));
memset(&ssn, 0, sizeof(ssn));
p1 = UTHBuildPacket(NULL, 0, IPPROTO_TCP);
FAIL_IF(p1 == NULL);
p2 = UTHBuildPacket(NULL, 0, IPPROTO_TCP);
FAIL_IF(p2 == NULL);
p1->BypassPacketsFlow = BypassCallback;
p2->BypassPacketsFlow = BypassCallback;
FLOW_INITIALIZE(&f);
f.protoctx = (void *)&ssn;
f.proto = IPPROTO_TCP;
f.flags |= FLOW_IPV4;
p1->flow = &f;
p1->flowflags |= FLOW_PKT_TOSERVER;
p1->flowflags |= FLOW_PKT_ESTABLISHED;
p1->flags |= PKT_HAS_FLOW|PKT_STREAM_EST;
p1->livedev = livedev;
p2->flow = &f;
p2->flowflags |= FLOW_PKT_TOCLIENT;
p2->flowflags |= FLOW_PKT_ESTABLISHED;
p2->flags |= PKT_HAS_FLOW|PKT_STREAM_EST;
p2->livedev = livedev;
f.alproto = ALPROTO_HTTP;
StreamTcpInitConfig(TRUE);
de_ctx = DetectEngineCtxInit();
FAIL_IF(de_ctx == NULL);
de_ctx->flags |= DE_QUIET;
char *sigs[3];
sigs[0] = "alert tcp any any -> any any (bypass; content:\"GET \"; sid:1;)";
sigs[1] = "alert http any any -> any any "
"(bypass; content:\"message\"; http_server_body; "
"sid:2;)";
sigs[2] = "alert http any any -> any any "
"(bypass; content:\"message\"; http_host; "
"sid:3;)";
FAIL_IF(UTHAppendSigs(de_ctx, sigs, 3) == 0);
SCSigRegisterSignatureOrderingFuncs(de_ctx);
SCSigOrderSignatures(de_ctx);
SCSigSignatureOrderingModuleCleanup(de_ctx);
SigGroupBuild(de_ctx);
DetectEngineThreadCtxInit(&th_v, (void *)de_ctx, (void *)&det_ctx);
FLOWLOCK_WRLOCK(&f);
int r = AppLayerParserParse(NULL, alp_tctx, &f, ALPROTO_HTTP,
STREAM_TOSERVER, http_buf1, http_len1);
FAIL_IF(r != 0);
FLOWLOCK_UNLOCK(&f);
http_state = f.alstate;
FAIL_IF(http_state == NULL);
/* do detect */
SigMatchSignatures(&th_v, de_ctx, det_ctx, p1);
FAIL_IF(PacketAlertCheck(p1, 1));
FLOWLOCK_WRLOCK(&f);
r = AppLayerParserParse(NULL, alp_tctx, &f, ALPROTO_HTTP, STREAM_TOCLIENT,
http_buf2, http_len2);
FAIL_IF(r != 0);
FLOWLOCK_UNLOCK(&f);
/* do detect */
SigMatchSignatures(&th_v, de_ctx, det_ctx, p2);
FAIL_IF(!(PacketAlertCheck(p2, 2)));
FAIL_IF(!(PacketAlertCheck(p1, 3)));
FAIL_IF(callback_var == 0);
StreamTcpFreeConfig(TRUE);
FLOW_DESTROY(&f);
UTHFreePacket(p1);
UTHFreePacket(p2);
ResetCallbackVar();
SCFree(livedev);
PASS;
}
#endif /* UNITTESTS */
void DetectBypassRegisterTests(void)
{
#ifdef UNITTESTS
UtRegisterTest("DetectBypassTestSig01", DetectBypassTestSig01);
#endif /* UNITTESTS */
}
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