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suricata/src/detect-dns-query.c

1140 lines
36 KiB
C

/* Copyright (C) 2013 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.
*/
/**
* \ingroup dnslayer
*
* @{
*/
/**
* \file
*
* \author Victor Julien <victor@inliniac.net>
*/
#include "suricata-common.h"
#include "threads.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-content.h"
#include "detect-pcre.h"
#include "flow.h"
#include "flow-util.h"
#include "flow-var.h"
#include "util-debug.h"
#include "util-unittest.h"
#include "util-spm.h"
#include "util-print.h"
#include "app-layer.h"
#include "app-layer-dns-common.h"
#include "detect-dns-query.h"
#include "util-unittest.h"
#include "util-unittest-helper.h"
static int DetectDnsQuerySetup (DetectEngineCtx *, Signature *, char *);
static void DetectDnsQueryRegisterTests(void);
/**
* \brief Registration function for keyword: http_uri
*/
void DetectDnsQueryRegister (void) {
sigmatch_table[DETECT_AL_DNS_QUERY].name = "dns_query";
sigmatch_table[DETECT_AL_DNS_QUERY].desc = "content modifier to match specifically and only on the DNS query-buffer";
sigmatch_table[DETECT_AL_DNS_QUERY].Match = NULL;
sigmatch_table[DETECT_AL_DNS_QUERY].AppLayerMatch = NULL;
sigmatch_table[DETECT_AL_DNS_QUERY].alproto = ALPROTO_DNS;
sigmatch_table[DETECT_AL_DNS_QUERY].Setup = DetectDnsQuerySetup;
sigmatch_table[DETECT_AL_DNS_QUERY].Free = NULL;
sigmatch_table[DETECT_AL_DNS_QUERY].RegisterTests = DetectDnsQueryRegisterTests;
sigmatch_table[DETECT_AL_DNS_QUERY].flags |= SIGMATCH_PAYLOAD;
}
/**
* \brief this function setups the dns_query modifier keyword used in the rule
*
* \param de_ctx Pointer to the Detection Engine Context
* \param s Pointer to the Signature to which the current keyword belongs
* \param str Should hold an empty string always
*
* \retval 0 On success
* \retval -1 On failure
*/
static int DetectDnsQuerySetup(DetectEngineCtx *de_ctx, Signature *s, char *str)
{
s->list = DETECT_SM_LIST_DNSQUERY_MATCH;
return 0;
}
/**
* \brief Run the pattern matcher against the queries
*
* \param f locked flow
* \param dns_state initialized dns state
*
* \warning Make sure the flow/state is locked
* \todo what should we return? Just the fact that we matched?
*/
uint32_t DetectDnsQueryInspectMpm(DetectEngineThreadCtx *det_ctx, Flow *f,
DNSState *dns_state, uint8_t flags, void *txv,
uint64_t tx_id)
{
SCEnter();
DNSTransaction *tx = (DNSTransaction *)txv;
DNSQueryEntry *query = NULL;
uint8_t *buffer;
uint16_t buffer_len;
uint32_t cnt = 0;
TAILQ_FOREACH(query, &tx->query_list, next) {
SCLogDebug("tx %p query %p", tx, query);
buffer = (uint8_t *)((uint8_t *)query + sizeof(DNSQueryEntry));
buffer_len = query->len;
cnt += DnsQueryPatternSearch(det_ctx,
buffer, buffer_len,
flags);
}
SCReturnUInt(cnt);
}
#ifdef UNITTESTS
/** \test simple google.com query matching */
static int DetectDnsQueryTest01(void) {
/* google.com */
uint8_t buf[] = { 0x10, 0x32, 0x01, 0x00, 0x00, 0x01,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x06, 0x67, 0x6F, 0x6F, 0x67, 0x6C,
0x65, 0x03, 0x63, 0x6F, 0x6D, 0x00,
0x00, 0x10, 0x00, 0x01, };
int result = 0;
Flow f;
DNSState *dns_state = NULL;
Packet *p = NULL;
Signature *s = NULL;
ThreadVars tv;
DetectEngineThreadCtx *det_ctx = NULL;
memset(&tv, 0, sizeof(ThreadVars));
memset(&f, 0, sizeof(Flow));
p = UTHBuildPacketReal(buf, sizeof(buf), IPPROTO_UDP,
"192.168.1.5", "192.168.1.1",
41424, 53);
FLOW_INITIALIZE(&f);
f.flags |= FLOW_IPV4;
f.proto = IPPROTO_UDP;
p->flow = &f;
p->flags |= PKT_HAS_FLOW;
p->flowflags |= FLOW_PKT_TOSERVER;
f.alproto = ALPROTO_DNS_UDP;
DetectEngineCtx *de_ctx = DetectEngineCtxInit();
if (de_ctx == NULL) {
goto end;
}
de_ctx->mpm_matcher = DEFAULT_MPM;
de_ctx->flags |= DE_QUIET;
s = DetectEngineAppendSig(de_ctx, "alert dnsudp any any -> any any "
"(msg:\"Test dns_query option\"; "
"dns_query; content:\"google\"; nocase; sid:1;)");
if (s == NULL) {
goto end;
}
SigGroupBuild(de_ctx);
DetectEngineThreadCtxInit(&tv, (void *)de_ctx, (void *)&det_ctx);
SCMutexLock(&f.m);
int r = AppLayerParse(NULL, &f, ALPROTO_DNS_UDP, STREAM_TOSERVER, buf, sizeof(buf));
if (r != 0) {
printf("toserver chunk 1 returned %" PRId32 ", expected 0: ", r);
SCMutexUnlock(&f.m);
goto end;
}
SCMutexUnlock(&f.m);
dns_state = f.alstate;
if (dns_state == NULL) {
printf("no dns state: ");
goto end;
}
/* do detect */
SigMatchSignatures(&tv, de_ctx, det_ctx, p);
if (!(PacketAlertCheck(p, 1))) {
printf("sig 1 didn't alert, but it should have: ");
goto end;
}
result = 1;
end:
if (det_ctx != NULL)
DetectEngineThreadCtxDeinit(&tv, det_ctx);
if (de_ctx != NULL)
SigGroupCleanup(de_ctx);
if (de_ctx != NULL)
DetectEngineCtxFree(de_ctx);
FLOW_DESTROY(&f);
UTHFreePacket(p);
return result;
}
/** \test multi tx google.(com|net) query matching */
static int DetectDnsQueryTest02(void) {
/* google.com */
uint8_t buf1[] = { 0x10, 0x32, 0x01, 0x00, 0x00, 0x01,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x06, 0x67, 0x6F, 0x6F, 0x67, 0x6C,
0x65, 0x03, 0x63, 0x6F, 0x6D, 0x00,
0x00, 0x01, 0x00, 0x01, };
uint8_t buf2[] = { 0x10, 0x32, /* tx id */
0x81, 0x80, /* flags: resp, recursion desired, recusion available */
0x00, 0x01, /* 1 query */
0x00, 0x01, /* 1 answer */
0x00, 0x00, 0x00, 0x00, /* no auth rr, additional rr */
/* query record */
0x06, 0x67, 0x6F, 0x6F, 0x67, 0x6C, /* name */
0x65, 0x03, 0x63, 0x6F, 0x6D, 0x00, /* name cont */
0x00, 0x01, 0x00, 0x01, /* type a, class in */
/* answer */
0xc0, 0x0c, /* ref to name in query above */
0x00, 0x01, 0x00, 0x01, /* type a, class in */
0x00, 0x01, 0x40, 0xef, /* ttl */
0x00, 0x04, /* data len */
0x01, 0x02, 0x03, 0x04 }; /* addr */
/* google.net */
uint8_t buf3[] = { 0x11, 0x33, 0x01, 0x00, 0x00, 0x01,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x06, 0x67, 0x6F, 0x6F, 0x67, 0x6C,
0x65, 0x03, 0x6E, 0x65, 0x74, 0x00,
0x00, 0x10, 0x00, 0x01, };
int result = 0;
Flow f;
DNSState *dns_state = NULL;
Packet *p1 = NULL, *p2 = NULL, *p3 = NULL;
Signature *s = NULL;
ThreadVars tv;
DetectEngineThreadCtx *det_ctx = NULL;
memset(&tv, 0, sizeof(ThreadVars));
memset(&f, 0, sizeof(Flow));
p1 = UTHBuildPacketReal(buf1, sizeof(buf1), IPPROTO_UDP,
"192.168.1.5", "192.168.1.1",
41424, 53);
p2 = UTHBuildPacketReal(buf1, sizeof(buf1), IPPROTO_UDP,
"192.168.1.5", "192.168.1.1",
41424, 53);
p3 = UTHBuildPacketReal(buf1, sizeof(buf1), IPPROTO_UDP,
"192.168.1.5", "192.168.1.1",
41424, 53);
FLOW_INITIALIZE(&f);
f.flags |= FLOW_IPV4;
f.proto = IPPROTO_UDP;
f.alproto = ALPROTO_DNS_UDP;
p1->flow = &f;
p1->flags |= PKT_HAS_FLOW;
p1->flowflags |= FLOW_PKT_TOSERVER;
p1->pcap_cnt = 1;
p2->flow = &f;
p2->flags |= PKT_HAS_FLOW;
p2->flowflags |= FLOW_PKT_TOCLIENT;
p2->pcap_cnt = 2;
p3->flow = &f;
p3->flags |= PKT_HAS_FLOW;
p3->flowflags |= FLOW_PKT_TOSERVER;
p3->pcap_cnt = 3;
DetectEngineCtx *de_ctx = DetectEngineCtxInit();
if (de_ctx == NULL) {
goto end;
}
de_ctx->mpm_matcher = DEFAULT_MPM;
de_ctx->flags |= DE_QUIET;
s = DetectEngineAppendSig(de_ctx, "alert dnsudp any any -> any any "
"(msg:\"Test dns_query option\"; "
"dns_query; content:\"google.com\"; nocase; sid:1;)");
if (s == NULL) {
goto end;
}
s = DetectEngineAppendSig(de_ctx, "alert dnsudp any any -> any any "
"(msg:\"Test dns_query option\"; "
"dns_query; content:\"google.net\"; nocase; sid:2;)");
if (s == NULL) {
goto end;
}
SigGroupBuild(de_ctx);
DetectEngineThreadCtxInit(&tv, (void *)de_ctx, (void *)&det_ctx);
SCMutexLock(&f.m);
int r = AppLayerParse(NULL, &f, ALPROTO_DNS_UDP, STREAM_TOSERVER, buf1, sizeof(buf1));
if (r != 0) {
printf("toserver chunk 1 returned %" PRId32 ", expected 0: ", r);
SCMutexUnlock(&f.m);
goto end;
}
SCMutexUnlock(&f.m);
dns_state = f.alstate;
if (dns_state == NULL) {
printf("no dns state: ");
goto end;
}
/* do detect */
SigMatchSignatures(&tv, de_ctx, det_ctx, p1);
if (!(PacketAlertCheck(p1, 1))) {
printf("(p1) sig 1 didn't alert, but it should have: ");
goto end;
}
if (PacketAlertCheck(p1, 2)) {
printf("(p1) sig 2 did alert, but it should not have: ");
goto end;
}
SCMutexLock(&f.m);
r = AppLayerParse(NULL, &f, ALPROTO_DNS_UDP, STREAM_TOCLIENT, buf2, sizeof(buf2));
if (r != 0) {
printf("toserver client 1 returned %" PRId32 ", expected 0: ", r);
SCMutexUnlock(&f.m);
goto end;
}
SCMutexUnlock(&f.m);
/* do detect */
SigMatchSignatures(&tv, de_ctx, det_ctx, p2);
if (PacketAlertCheck(p2, 1)) {
printf("(p2) sig 1 alerted, but it should not have: ");
goto end;
}
if (PacketAlertCheck(p2, 2)) {
printf("(p2) sig 2 alerted, but it should not have: ");
goto end;
}
SCMutexLock(&f.m);
r = AppLayerParse(NULL, &f, ALPROTO_DNS_UDP, STREAM_TOSERVER, buf3, sizeof(buf3));
if (r != 0) {
printf("toserver chunk 3 returned %" PRId32 ", expected 0: ", r);
SCMutexUnlock(&f.m);
goto end;
}
SCMutexUnlock(&f.m);
/* do detect */
SigMatchSignatures(&tv, de_ctx, det_ctx, p3);
if (PacketAlertCheck(p3, 1)) {
printf("(p3) sig 1 alerted, but it should not have: ");
goto end;
}
if (!(PacketAlertCheck(p3, 2))) {
printf("(p3) sig 2 didn't alert, but it should have: ");
goto end;
}
result = 1;
end:
if (det_ctx != NULL)
DetectEngineThreadCtxDeinit(&tv, det_ctx);
if (de_ctx != NULL)
SigGroupCleanup(de_ctx);
if (de_ctx != NULL)
DetectEngineCtxFree(de_ctx);
FLOW_DESTROY(&f);
UTHFreePacket(p1);
UTHFreePacket(p2);
UTHFreePacket(p3);
return result;
}
/** \test simple google.com query matching (TCP) */
static int DetectDnsQueryTest03(void) {
/* google.com */
uint8_t buf[] = { 0x00, 28,
0x10, 0x32, 0x01, 0x00, 0x00, 0x01,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x06, 0x67, 0x6F, 0x6F, 0x67, 0x6C,
0x65, 0x03, 0x63, 0x6F, 0x6D, 0x00,
0x00, 0x10, 0x00, 0x01, };
int result = 0;
Flow f;
DNSState *dns_state = NULL;
Packet *p = NULL;
Signature *s = NULL;
ThreadVars tv;
DetectEngineThreadCtx *det_ctx = NULL;
TcpSession ssn;
memset(&tv, 0, sizeof(ThreadVars));
memset(&f, 0, sizeof(Flow));
memset(&ssn, 0, sizeof(TcpSession));
p = UTHBuildPacketReal(buf, sizeof(buf), IPPROTO_TCP,
"192.168.1.5", "192.168.1.1",
41424, 53);
FLOW_INITIALIZE(&f);
f.protoctx = (void *)&ssn;
f.flags |= FLOW_IPV4;
f.proto = IPPROTO_TCP;
p->flow = &f;
p->flags |= PKT_HAS_FLOW|PKT_STREAM_EST;
p->flowflags |= FLOW_PKT_TOSERVER|FLOW_PKT_ESTABLISHED;
f.alproto = ALPROTO_DNS_TCP;
StreamTcpInitConfig(TRUE);
DetectEngineCtx *de_ctx = DetectEngineCtxInit();
if (de_ctx == NULL) {
goto end;
}
de_ctx->mpm_matcher = DEFAULT_MPM;
de_ctx->flags |= DE_QUIET;
s = DetectEngineAppendSig(de_ctx, "alert dnstcp any any -> any any "
"(msg:\"Test dns_query option\"; "
"content:\"google\"; nocase; dns_query; sid:1;)");
if (s == NULL) {
goto end;
}
SigGroupBuild(de_ctx);
DetectEngineThreadCtxInit(&tv, (void *)de_ctx, (void *)&det_ctx);
SCMutexLock(&f.m);
int r = AppLayerParse(NULL, &f, ALPROTO_DNS_TCP, STREAM_TOSERVER, buf, sizeof(buf));
if (r != 0) {
printf("toserver chunk 1 returned %" PRId32 ", expected 0: ", r);
SCMutexUnlock(&f.m);
goto end;
}
SCMutexUnlock(&f.m);
dns_state = f.alstate;
if (dns_state == NULL) {
printf("no dns state: ");
goto end;
}
/* do detect */
SigMatchSignatures(&tv, de_ctx, det_ctx, p);
if (!(PacketAlertCheck(p, 1))) {
printf("sig 1 didn't alert, but it should have: ");
goto end;
}
result = 1;
end:
if (det_ctx != NULL)
DetectEngineThreadCtxDeinit(&tv, det_ctx);
if (de_ctx != NULL)
SigGroupCleanup(de_ctx);
if (de_ctx != NULL)
DetectEngineCtxFree(de_ctx);
StreamTcpFreeConfig(TRUE);
FLOW_DESTROY(&f);
UTHFreePacket(p);
return result;
}
/** \test simple google.com query matching (TCP splicing) */
static int DetectDnsQueryTest04(void) {
/* google.com */
uint8_t buf1[] = { 0x00, 28,
0x10, 0x32, 0x01, 0x00, 0x00, 0x01,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, };
uint8_t buf2[] = { 0x06, 0x67, 0x6F, 0x6F, 0x67, 0x6C,
0x65, 0x03, 0x63, 0x6F, 0x6D, 0x00,
0x00, 0x10, 0x00, 0x01, };
int result = 0;
Flow f;
DNSState *dns_state = NULL;
Packet *p1 = NULL, *p2 = NULL;
Signature *s = NULL;
ThreadVars tv;
DetectEngineThreadCtx *det_ctx = NULL;
TcpSession ssn;
memset(&tv, 0, sizeof(ThreadVars));
memset(&f, 0, sizeof(Flow));
memset(&ssn, 0, sizeof(TcpSession));
p1 = UTHBuildPacketReal(buf1, sizeof(buf1), IPPROTO_TCP,
"192.168.1.5", "192.168.1.1",
41424, 53);
p2 = UTHBuildPacketReal(buf2, sizeof(buf2), IPPROTO_TCP,
"192.168.1.5", "192.168.1.1",
41424, 53);
FLOW_INITIALIZE(&f);
f.protoctx = (void *)&ssn;
f.flags |= FLOW_IPV4;
f.proto = IPPROTO_TCP;
f.alproto = ALPROTO_DNS_TCP;
p1->flow = &f;
p1->flags |= PKT_HAS_FLOW|PKT_STREAM_EST;
p1->flowflags |= FLOW_PKT_TOSERVER|FLOW_PKT_ESTABLISHED;
p2->flow = &f;
p2->flags |= PKT_HAS_FLOW|PKT_STREAM_EST;
p2->flowflags |= FLOW_PKT_TOSERVER|FLOW_PKT_ESTABLISHED;
StreamTcpInitConfig(TRUE);
DetectEngineCtx *de_ctx = DetectEngineCtxInit();
if (de_ctx == NULL) {
goto end;
}
de_ctx->mpm_matcher = DEFAULT_MPM;
de_ctx->flags |= DE_QUIET;
s = DetectEngineAppendSig(de_ctx, "alert dnstcp any any -> any any "
"(msg:\"Test dns_query option\"; "
"dns_query; content:\"google\"; nocase; sid:1;)");
if (s == NULL) {
goto end;
}
SigGroupBuild(de_ctx);
DetectEngineThreadCtxInit(&tv, (void *)de_ctx, (void *)&det_ctx);
SCMutexLock(&f.m);
int r = AppLayerParse(NULL, &f, ALPROTO_DNS_TCP, STREAM_TOSERVER, buf1, sizeof(buf1));
if (r != 0) {
printf("toserver chunk 1 returned %" PRId32 ", expected 0: ", r);
SCMutexUnlock(&f.m);
goto end;
}
SCMutexUnlock(&f.m);
dns_state = f.alstate;
if (dns_state == NULL) {
printf("no dns state: ");
goto end;
}
/* do detect */
SigMatchSignatures(&tv, de_ctx, det_ctx, p1);
if (PacketAlertCheck(p1, 1)) {
printf("sig 1 alerted, but it should not have: ");
goto end;
}
SCMutexLock(&f.m);
r = AppLayerParse(NULL, &f, ALPROTO_DNS_TCP, STREAM_TOSERVER, buf2, sizeof(buf2));
if (r != 0) {
printf("toserver chunk 1 returned %" PRId32 ", expected 0: ", r);
SCMutexUnlock(&f.m);
goto end;
}
SCMutexUnlock(&f.m);
/* do detect */
SigMatchSignatures(&tv, de_ctx, det_ctx, p2);
if (!(PacketAlertCheck(p2, 1))) {
printf("sig 1 didn't alert, but it should have: ");
goto end;
}
result = 1;
end:
if (det_ctx != NULL)
DetectEngineThreadCtxDeinit(&tv, det_ctx);
if (de_ctx != NULL)
SigGroupCleanup(de_ctx);
if (de_ctx != NULL)
DetectEngineCtxFree(de_ctx);
StreamTcpFreeConfig(TRUE);
FLOW_DESTROY(&f);
UTHFreePacket(p1);
UTHFreePacket(p2);
return result;
}
/** \test simple google.com query matching (TCP splicing) */
static int DetectDnsQueryTest05(void) {
/* google.com in 2 chunks (buf1 and buf2) */
uint8_t buf1[] = { 0x00, 28, /* len 28 */
0x10, 0x32, 0x01, 0x00, 0x00, 0x01,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, };
uint8_t buf2[] = { 0x06, 0x67, 0x6F, 0x6F, 0x67, 0x6C,
0x65, 0x03, 0x63, 0x6F, 0x6D, 0x00,
0x00, 0x10, 0x00, 0x01, };
uint8_t buf3[] = { 0x00, 44, /* len 44 */
0x10, 0x32, /* tx id */
0x81, 0x80, /* flags: resp, recursion desired, recusion available */
0x00, 0x01, /* 1 query */
0x00, 0x01, /* 1 answer */
0x00, 0x00, 0x00, 0x00, /* no auth rr, additional rr */
/* query record */
0x06, 0x67, 0x6F, 0x6F, 0x67, 0x6C, /* name */
0x65, 0x03, 0x63, 0x6F, 0x6D, 0x00, /* name cont */
0x00, 0x01, 0x00, 0x01, /* type a, class in */
/* answer */
0xc0, 0x0c, /* ref to name in query above */
0x00, 0x01, 0x00, 0x01, /* type a, class in */
0x00, 0x01, 0x40, 0xef, /* ttl */
0x00, 0x04, /* data len */
0x01, 0x02, 0x03, 0x04 }; /* addr */
/* google.net */
uint8_t buf4[] = { 0x00, 28, /* len 28 */
0x11, 0x33, 0x01, 0x00, 0x00, 0x01,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x06, 0x67, 0x6F, 0x6F, 0x67, 0x6C,
0x65, 0x03, 0x6E, 0x65, 0x74, 0x00,
0x00, 0x10, 0x00, 0x01, };
int result = 0;
Flow f;
DNSState *dns_state = NULL;
Packet *p1 = NULL, *p2 = NULL, *p3 = NULL, *p4 = NULL;
Signature *s = NULL;
ThreadVars tv;
DetectEngineThreadCtx *det_ctx = NULL;
TcpSession ssn;
memset(&tv, 0, sizeof(ThreadVars));
memset(&f, 0, sizeof(Flow));
memset(&ssn, 0, sizeof(TcpSession));
p1 = UTHBuildPacketReal(buf1, sizeof(buf1), IPPROTO_TCP,
"192.168.1.5", "192.168.1.1",
41424, 53);
p2 = UTHBuildPacketReal(buf2, sizeof(buf2), IPPROTO_TCP,
"192.168.1.5", "192.168.1.1",
41424, 53);
p3 = UTHBuildPacketReal(buf3, sizeof(buf3), IPPROTO_TCP,
"192.168.1.5", "192.168.1.1",
41424, 53);
p4 = UTHBuildPacketReal(buf4, sizeof(buf4), IPPROTO_TCP,
"192.168.1.5", "192.168.1.1",
41424, 53);
FLOW_INITIALIZE(&f);
f.protoctx = (void *)&ssn;
f.flags |= FLOW_IPV4;
f.proto = IPPROTO_TCP;
f.alproto = ALPROTO_DNS_TCP;
p1->flow = &f;
p1->flags |= PKT_HAS_FLOW|PKT_STREAM_EST;
p1->flowflags |= FLOW_PKT_TOSERVER|FLOW_PKT_ESTABLISHED;
p2->flow = &f;
p2->flags |= PKT_HAS_FLOW|PKT_STREAM_EST;
p2->flowflags |= FLOW_PKT_TOSERVER|FLOW_PKT_ESTABLISHED;
p3->flow = &f;
p3->flags |= PKT_HAS_FLOW|PKT_STREAM_EST;
p3->flowflags |= FLOW_PKT_TOCLIENT|FLOW_PKT_ESTABLISHED;
p4->flow = &f;
p4->flags |= PKT_HAS_FLOW|PKT_STREAM_EST;
p4->flowflags |= FLOW_PKT_TOSERVER|FLOW_PKT_ESTABLISHED;
StreamTcpInitConfig(TRUE);
DetectEngineCtx *de_ctx = DetectEngineCtxInit();
if (de_ctx == NULL) {
goto end;
}
de_ctx->mpm_matcher = DEFAULT_MPM;
de_ctx->flags |= DE_QUIET;
s = DetectEngineAppendSig(de_ctx, "alert dnstcp any any -> any any "
"(msg:\"Test dns_query option\"; "
"dns_query; content:\"google.com\"; nocase; sid:1;)");
if (s == NULL) {
goto end;
}
s = DetectEngineAppendSig(de_ctx, "alert dnstcp any any -> any any "
"(msg:\"Test dns_query option\"; "
"dns_query; content:\"google.net\"; nocase; sid:2;)");
if (s == NULL) {
goto end;
}
SigGroupBuild(de_ctx);
DetectEngineThreadCtxInit(&tv, (void *)de_ctx, (void *)&det_ctx);
SCMutexLock(&f.m);
int r = AppLayerParse(NULL, &f, ALPROTO_DNS_TCP, STREAM_TOSERVER, buf1, sizeof(buf1));
if (r != 0) {
printf("toserver chunk 1 returned %" PRId32 ", expected 0: ", r);
SCMutexUnlock(&f.m);
goto end;
}
SCMutexUnlock(&f.m);
dns_state = f.alstate;
if (dns_state == NULL) {
printf("no dns state: ");
goto end;
}
/* do detect */
SigMatchSignatures(&tv, de_ctx, det_ctx, p1);
if (PacketAlertCheck(p1, 1)) {
printf("(p1) sig 1 alerted, but it should not have: ");
goto end;
}
if (PacketAlertCheck(p1, 2)) {
printf("(p1) sig 2 did alert, but it should not have: ");
goto end;
}
SCMutexLock(&f.m);
r = AppLayerParse(NULL, &f, ALPROTO_DNS_TCP, STREAM_TOSERVER, buf2, sizeof(buf2));
if (r != 0) {
printf("toserver chunk 2 returned %" PRId32 ", expected 0: ", r);
SCMutexUnlock(&f.m);
goto end;
}
SCMutexUnlock(&f.m);
/* do detect */
SigMatchSignatures(&tv, de_ctx, det_ctx, p2);
if (!(PacketAlertCheck(p2, 1))) {
printf("sig 1 didn't alert, but it should have: ");
goto end;
}
if (PacketAlertCheck(p2, 2)) {
printf("(p2) sig 2 did alert, but it should not have: ");
goto end;
}
SCMutexLock(&f.m);
r = AppLayerParse(NULL, &f, ALPROTO_DNS_TCP, STREAM_TOCLIENT, buf3, sizeof(buf3));
if (r != 0) {
printf("toclient chunk 1 returned %" PRId32 ", expected 0: ", r);
SCMutexUnlock(&f.m);
goto end;
}
SCMutexUnlock(&f.m);
/* do detect */
SigMatchSignatures(&tv, de_ctx, det_ctx, p3);
if (PacketAlertCheck(p3, 1)) {
printf("sig 1 did alert, but it should not have: ");
goto end;
}
if (PacketAlertCheck(p3, 2)) {
printf("(p3) sig 2 did alert, but it should not have: ");
goto end;
}
SCMutexLock(&f.m);
r = AppLayerParse(NULL, &f, ALPROTO_DNS_TCP, STREAM_TOSERVER, buf4, sizeof(buf4));
if (r != 0) {
printf("toserver chunk 3 returned %" PRId32 ", expected 0: ", r);
SCMutexUnlock(&f.m);
goto end;
}
SCMutexUnlock(&f.m);
/* do detect */
SigMatchSignatures(&tv, de_ctx, det_ctx, p4);
if (PacketAlertCheck(p4, 1)) {
printf("(p4) sig 1 did alert, but it should not have: ");
goto end;
}
if (!(PacketAlertCheck(p4, 2))) {
printf("sig 1 didn't alert, but it should have: ");
goto end;
}
result = 1;
end:
if (det_ctx != NULL)
DetectEngineThreadCtxDeinit(&tv, det_ctx);
if (de_ctx != NULL)
SigGroupCleanup(de_ctx);
if (de_ctx != NULL)
DetectEngineCtxFree(de_ctx);
StreamTcpFreeConfig(TRUE);
FLOW_DESTROY(&f);
UTHFreePacket(p1);
UTHFreePacket(p2);
UTHFreePacket(p3);
UTHFreePacket(p4);
return result;
}
/** \test simple google.com query matching, pcre */
static int DetectDnsQueryTest06(void) {
/* google.com */
uint8_t buf[] = { 0x10, 0x32, 0x01, 0x00, 0x00, 0x01,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x06, 0x67, 0x6F, 0x6F, 0x67, 0x6C,
0x65, 0x03, 0x63, 0x6F, 0x6D, 0x00,
0x00, 0x10, 0x00, 0x01, };
int result = 0;
Flow f;
DNSState *dns_state = NULL;
Packet *p = NULL;
Signature *s = NULL;
ThreadVars tv;
DetectEngineThreadCtx *det_ctx = NULL;
memset(&tv, 0, sizeof(ThreadVars));
memset(&f, 0, sizeof(Flow));
p = UTHBuildPacketReal(buf, sizeof(buf), IPPROTO_UDP,
"192.168.1.5", "192.168.1.1",
41424, 53);
FLOW_INITIALIZE(&f);
f.flags |= FLOW_IPV4;
f.proto = IPPROTO_UDP;
p->flow = &f;
p->flags |= PKT_HAS_FLOW;
p->flowflags |= FLOW_PKT_TOSERVER;
f.alproto = ALPROTO_DNS_UDP;
DetectEngineCtx *de_ctx = DetectEngineCtxInit();
if (de_ctx == NULL) {
goto end;
}
de_ctx->mpm_matcher = DEFAULT_MPM;
de_ctx->flags |= DE_QUIET;
s = DetectEngineAppendSig(de_ctx, "alert dnsudp any any -> any any "
"(msg:\"Test dns_query option\"; "
"dns_query; content:\"google\"; nocase; "
"pcre:\"/google\\.com$/i\"; sid:1;)");
if (s == NULL) {
goto end;
}
s = DetectEngineAppendSig(de_ctx, "alert dnsudp any any -> any any "
"(msg:\"Test dns_query option\"; "
"dns_query; content:\"google\"; nocase; "
"pcre:\"/^\\.[a-z]{2,3}$/iR\"; sid:2;)");
if (s == NULL) {
goto end;
}
SigGroupBuild(de_ctx);
DetectEngineThreadCtxInit(&tv, (void *)de_ctx, (void *)&det_ctx);
SCMutexLock(&f.m);
int r = AppLayerParse(NULL, &f, ALPROTO_DNS_UDP, STREAM_TOSERVER, buf, sizeof(buf));
if (r != 0) {
printf("toserver chunk 1 returned %" PRId32 ", expected 0: ", r);
SCMutexUnlock(&f.m);
goto end;
}
SCMutexUnlock(&f.m);
dns_state = f.alstate;
if (dns_state == NULL) {
printf("no dns state: ");
goto end;
}
/* do detect */
SigMatchSignatures(&tv, de_ctx, det_ctx, p);
if (!(PacketAlertCheck(p, 1))) {
printf("sig 1 didn't alert, but it should have: ");
goto end;
}
if (!(PacketAlertCheck(p, 2))) {
printf("sig 2 didn't alert, but it should have: ");
goto end;
}
result = 1;
end:
if (det_ctx != NULL)
DetectEngineThreadCtxDeinit(&tv, det_ctx);
if (de_ctx != NULL)
SigGroupCleanup(de_ctx);
if (de_ctx != NULL)
DetectEngineCtxFree(de_ctx);
FLOW_DESTROY(&f);
UTHFreePacket(p);
return result;
}
/** \test multi tx google.(com|net) query matching +
* app layer event */
static int DetectDnsQueryTest07(void) {
/* google.com */
uint8_t buf1[] = { 0x10, 0x32, 0x01, 0x00, 0x00, 0x01,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x06, 0x67, 0x6F, 0x6F, 0x67, 0x6C,
0x65, 0x03, 0x63, 0x6F, 0x6D, 0x00,
0x00, 0x01, 0x00, 0x01, };
uint8_t buf2[] = { 0x10, 0x32, /* tx id */
0x81, 0x80|0x40, /* flags: resp, recursion desired, recusion available */
0x00, 0x01, /* 1 query */
0x00, 0x01, /* 1 answer */
0x00, 0x00, 0x00, 0x00, /* no auth rr, additional rr */
/* query record */
0x06, 0x67, 0x6F, 0x6F, 0x67, 0x6C, /* name */
0x65, 0x03, 0x63, 0x6F, 0x6D, 0x00, /* name cont */
0x00, 0x01, 0x00, 0x01, /* type a, class in */
/* answer */
0xc0, 0x0c, /* ref to name in query above */
0x00, 0x01, 0x00, 0x01, /* type a, class in */
0x00, 0x01, 0x40, 0xef, /* ttl */
0x00, 0x04, /* data len */
0x01, 0x02, 0x03, 0x04 }; /* addr */
/* google.net */
uint8_t buf3[] = { 0x11, 0x33, 0x01, 0x00, 0x00, 0x01,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x06, 0x67, 0x6F, 0x6F, 0x67, 0x6C,
0x65, 0x03, 0x6E, 0x65, 0x74, 0x00,
0x00, 0x10, 0x00, 0x01, };
int result = 0;
Flow f;
DNSState *dns_state = NULL;
Packet *p1 = NULL, *p2 = NULL, *p3 = NULL;
Signature *s = NULL;
ThreadVars tv;
DetectEngineThreadCtx *det_ctx = NULL;
memset(&tv, 0, sizeof(ThreadVars));
memset(&f, 0, sizeof(Flow));
p1 = UTHBuildPacketReal(buf1, sizeof(buf1), IPPROTO_UDP,
"192.168.1.5", "192.168.1.1",
41424, 53);
p2 = UTHBuildPacketReal(buf2, sizeof(buf2), IPPROTO_UDP,
"192.168.1.5", "192.168.1.1",
41424, 53);
p3 = UTHBuildPacketReal(buf3, sizeof(buf3), IPPROTO_UDP,
"192.168.1.5", "192.168.1.1",
41424, 53);
FLOW_INITIALIZE(&f);
f.flags |= FLOW_IPV4;
f.proto = IPPROTO_UDP;
f.alproto = ALPROTO_DNS_UDP;
p1->flow = &f;
p1->flags |= PKT_HAS_FLOW;
p1->flowflags |= FLOW_PKT_TOSERVER;
p1->pcap_cnt = 1;
p2->flow = &f;
p2->flags |= PKT_HAS_FLOW;
p2->flowflags |= FLOW_PKT_TOCLIENT;
p2->pcap_cnt = 2;
p3->flow = &f;
p3->flags |= PKT_HAS_FLOW;
p3->flowflags |= FLOW_PKT_TOSERVER;
p3->pcap_cnt = 3;
DetectEngineCtx *de_ctx = DetectEngineCtxInit();
if (de_ctx == NULL) {
goto end;
}
de_ctx->mpm_matcher = DEFAULT_MPM;
de_ctx->flags |= DE_QUIET;
s = DetectEngineAppendSig(de_ctx, "alert dnsudp any any -> any any "
"(msg:\"Test dns_query option\"; "
"dns_query; content:\"google.com\"; nocase; sid:1;)");
if (s == NULL) {
goto end;
}
s = DetectEngineAppendSig(de_ctx, "alert dnsudp any any -> any any "
"(msg:\"Test dns_query option\"; "
"dns_query; content:\"google.net\"; nocase; sid:2;)");
if (s == NULL) {
goto end;
}
s = DetectEngineAppendSig(de_ctx, "alert dnsudp any any -> any any "
"(msg:\"Test Z flag event\"; "
"app-layer-event:dns.z_flag_set; sid:3;)");
if (s == NULL) {
goto end;
}
SigGroupBuild(de_ctx);
DetectEngineThreadCtxInit(&tv, (void *)de_ctx, (void *)&det_ctx);
SCMutexLock(&f.m);
int r = AppLayerParse(NULL, &f, ALPROTO_DNS_UDP, STREAM_TOSERVER, buf1, sizeof(buf1));
if (r != 0) {
printf("toserver chunk 1 returned %" PRId32 ", expected 0: ", r);
SCMutexUnlock(&f.m);
goto end;
}
SCMutexUnlock(&f.m);
dns_state = f.alstate;
if (dns_state == NULL) {
printf("no dns state: ");
goto end;
}
/* do detect */
SigMatchSignatures(&tv, de_ctx, det_ctx, p1);
if (!(PacketAlertCheck(p1, 1))) {
printf("(p1) sig 1 didn't alert, but it should have: ");
goto end;
}
if (PacketAlertCheck(p1, 2)) {
printf("(p1) sig 2 did alert, but it should not have: ");
goto end;
}
SCMutexLock(&f.m);
r = AppLayerParse(NULL, &f, ALPROTO_DNS_UDP, STREAM_TOCLIENT, buf2, sizeof(buf2));
if (r != -1) {
printf("toserver client 1 returned %" PRId32 ", expected 0: ", r);
SCMutexUnlock(&f.m);
goto end;
}
SCMutexUnlock(&f.m);
/* do detect */
SigMatchSignatures(&tv, de_ctx, det_ctx, p2);
if (PacketAlertCheck(p2, 1)) {
printf("(p2) sig 1 alerted, but it should not have: ");
goto end;
}
if (PacketAlertCheck(p2, 2)) {
printf("(p2) sig 2 alerted, but it should not have: ");
goto end;
}
if (!(PacketAlertCheck(p2, 3))) {
printf("(p2) sig 3 didn't alert, but it should have: ");
goto end;
}
SCMutexLock(&f.m);
r = AppLayerParse(NULL, &f, ALPROTO_DNS_UDP, STREAM_TOSERVER, buf3, sizeof(buf3));
if (r != 0) {
printf("toserver chunk 3 returned %" PRId32 ", expected 0: ", r);
SCMutexUnlock(&f.m);
goto end;
}
SCMutexUnlock(&f.m);
/* do detect */
SigMatchSignatures(&tv, de_ctx, det_ctx, p3);
if (PacketAlertCheck(p3, 1)) {
printf("(p3) sig 1 alerted, but it should not have: ");
goto end;
}
if (!(PacketAlertCheck(p3, 2))) {
printf("(p3) sig 2 didn't alert, but it should have: ");
goto end;
}
/** \todo should not alert, bug #839
if (PacketAlertCheck(p3, 3)) {
printf("(p3) sig 3 did alert, but it should not have: ");
goto end;
}
*/
result = 1;
end:
if (det_ctx != NULL)
DetectEngineThreadCtxDeinit(&tv, det_ctx);
if (de_ctx != NULL)
SigGroupCleanup(de_ctx);
if (de_ctx != NULL)
DetectEngineCtxFree(de_ctx);
FLOW_DESTROY(&f);
UTHFreePacket(p1);
UTHFreePacket(p2);
UTHFreePacket(p3);
return result;
}
#endif
static void DetectDnsQueryRegisterTests(void) {
#ifdef UNITTESTS
UtRegisterTest("DetectDnsQueryTest01", DetectDnsQueryTest01, 1);
UtRegisterTest("DetectDnsQueryTest02", DetectDnsQueryTest02, 1);
UtRegisterTest("DetectDnsQueryTest03 -- tcp", DetectDnsQueryTest03, 1);
UtRegisterTest("DetectDnsQueryTest04 -- tcp splicing", DetectDnsQueryTest04, 1);
UtRegisterTest("DetectDnsQueryTest05 -- tcp splicing/multi tx", DetectDnsQueryTest05, 1);
UtRegisterTest("DetectDnsQueryTest06 -- pcre", DetectDnsQueryTest06, 1);
UtRegisterTest("DetectDnsQueryTest07 -- app layer event", DetectDnsQueryTest07, 1);
#endif
}