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suricata/src/detect-dns-query.c

955 lines
31 KiB
C

/* Copyright (C) 2013-2018 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-engine-prefilter.h"
#include "detect-engine-content-inspection.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 "stream-tcp.h"
#include "app-layer.h"
#include "app-layer-parser.h"
#include "detect-dns-query.h"
#include "util-unittest-helper.h"
#include "rust.h"
static int DetectDnsQuerySetup (DetectEngineCtx *, Signature *, const char *);
#ifdef UNITTESTS
static void DetectDnsQueryRegisterTests(void);
#endif
static int g_dns_query_buffer_id = 0;
struct DnsQueryGetDataArgs {
uint32_t local_id; /**< used as index into thread inspect array */
void *txv;
};
static InspectionBuffer *DnsQueryGetData(DetectEngineThreadCtx *det_ctx,
const DetectEngineTransforms *transforms,
Flow *f, struct DnsQueryGetDataArgs *cbdata, int list_id, bool first)
{
SCEnter();
InspectionBuffer *buffer =
InspectionBufferMultipleForListGet(det_ctx, list_id, cbdata->local_id);
if (buffer == NULL)
return NULL;
if (!first && buffer->inspect != NULL)
return buffer;
const uint8_t *data;
uint32_t data_len;
if (rs_dns_tx_get_query_name(cbdata->txv, cbdata->local_id, &data, &data_len) == 0) {
return NULL;
}
InspectionBufferSetupMulti(buffer, transforms, data, data_len);
SCReturnPtr(buffer, "InspectionBuffer");
}
static int DetectEngineInspectDnsQuery(
DetectEngineCtx *de_ctx, DetectEngineThreadCtx *det_ctx,
const DetectEngineAppInspectionEngine *engine,
const Signature *s,
Flow *f, uint8_t flags, void *alstate, void *txv, uint64_t tx_id)
{
uint32_t local_id = 0;
const DetectEngineTransforms *transforms = NULL;
if (!engine->mpm) {
transforms = engine->v2.transforms;
}
while(1) {
struct DnsQueryGetDataArgs cbdata = { local_id, txv, };
InspectionBuffer *buffer = DnsQueryGetData(det_ctx,
transforms, f, &cbdata, engine->sm_list, false);
if (buffer == NULL || buffer->inspect == NULL)
break;
det_ctx->buffer_offset = 0;
det_ctx->discontinue_matching = 0;
det_ctx->inspection_recursion_counter = 0;
const int match = DetectEngineContentInspection(de_ctx, det_ctx, s, engine->smd,
NULL, f,
(uint8_t *)buffer->inspect,
buffer->inspect_len,
buffer->inspect_offset, DETECT_CI_FLAGS_SINGLE,
DETECT_ENGINE_CONTENT_INSPECTION_MODE_STATE);
if (match == 1) {
return DETECT_ENGINE_INSPECT_SIG_MATCH;
}
local_id++;
}
return DETECT_ENGINE_INSPECT_SIG_NO_MATCH;
}
typedef struct PrefilterMpmDnsQuery {
int list_id;
const MpmCtx *mpm_ctx;
const DetectEngineTransforms *transforms;
} PrefilterMpmDnsQuery;
/** \brief DnsQuery DnsQuery Mpm prefilter callback
*
* \param det_ctx detection engine thread ctx
* \param p packet to inspect
* \param f flow to inspect
* \param txv tx to inspect
* \param pectx inspection context
*/
static void PrefilterTxDnsQuery(DetectEngineThreadCtx *det_ctx,
const void *pectx,
Packet *p, Flow *f, void *txv,
const uint64_t idx, const uint8_t flags)
{
SCEnter();
const PrefilterMpmDnsQuery *ctx = (const PrefilterMpmDnsQuery *)pectx;
const MpmCtx *mpm_ctx = ctx->mpm_ctx;
const int list_id = ctx->list_id;
uint32_t local_id = 0;
while(1) {
// loop until we get a NULL
struct DnsQueryGetDataArgs cbdata = { local_id, txv };
InspectionBuffer *buffer = DnsQueryGetData(det_ctx, ctx->transforms,
f, &cbdata, list_id, true);
if (buffer == NULL)
break;
if (buffer->inspect_len >= mpm_ctx->minlen) {
(void)mpm_table[mpm_ctx->mpm_type].Search(mpm_ctx,
&det_ctx->mtcu, &det_ctx->pmq,
buffer->inspect, buffer->inspect_len);
}
local_id++;
}
}
static void PrefilterMpmDnsQueryFree(void *ptr)
{
SCFree(ptr);
}
static int PrefilterMpmDnsQueryRegister(DetectEngineCtx *de_ctx,
SigGroupHead *sgh, MpmCtx *mpm_ctx,
const DetectBufferMpmRegistery *mpm_reg, int list_id)
{
PrefilterMpmDnsQuery *pectx = SCCalloc(1, sizeof(*pectx));
if (pectx == NULL)
return -1;
pectx->list_id = list_id;
pectx->mpm_ctx = mpm_ctx;
pectx->transforms = &mpm_reg->transforms;
return PrefilterAppendTxEngine(de_ctx, sgh, PrefilterTxDnsQuery,
mpm_reg->app_v2.alproto, mpm_reg->app_v2.tx_min_progress,
pectx, PrefilterMpmDnsQueryFree, mpm_reg->pname);
}
#ifdef HAVE_LUA
static int DetectEngineInspectDnsRequest(DetectEngineCtx *de_ctx, DetectEngineThreadCtx *det_ctx,
const struct DetectEngineAppInspectionEngine_ *engine, const Signature *s, Flow *f,
uint8_t flags, void *alstate, void *txv, uint64_t tx_id)
{
return DetectEngineInspectGenericList(
de_ctx, det_ctx, s, engine->smd, f, flags, alstate, txv, tx_id);
}
static int DetectEngineInspectDnsResponse(DetectEngineCtx *de_ctx, DetectEngineThreadCtx *det_ctx,
const struct DetectEngineAppInspectionEngine_ *engine, const Signature *s, Flow *f,
uint8_t flags, void *alstate, void *txv, uint64_t tx_id)
{
return DetectEngineInspectGenericList(
de_ctx, det_ctx, s, engine->smd, f, flags, alstate, txv, tx_id);
}
#endif
/**
* \brief Registration function for keyword: dns_query
*/
void DetectDnsQueryRegister (void)
{
sigmatch_table[DETECT_AL_DNS_QUERY].name = "dns.query";
sigmatch_table[DETECT_AL_DNS_QUERY].alias = "dns_query";
sigmatch_table[DETECT_AL_DNS_QUERY].desc = "sticky buffer to match DNS query-buffer";
sigmatch_table[DETECT_AL_DNS_QUERY].url = "/rules/dns-keywords.html#dns-query";
sigmatch_table[DETECT_AL_DNS_QUERY].Setup = DetectDnsQuerySetup;
#ifdef UNITTESTS
sigmatch_table[DETECT_AL_DNS_QUERY].RegisterTests = DetectDnsQueryRegisterTests;
#endif
sigmatch_table[DETECT_AL_DNS_QUERY].flags |= SIGMATCH_NOOPT;
sigmatch_table[DETECT_AL_DNS_QUERY].flags |= SIGMATCH_INFO_STICKY_BUFFER;
DetectAppLayerMpmRegister2("dns_query", SIG_FLAG_TOSERVER, 2,
PrefilterMpmDnsQueryRegister, NULL,
ALPROTO_DNS, 1);
DetectAppLayerInspectEngineRegister2("dns_query",
ALPROTO_DNS, SIG_FLAG_TOSERVER, 1,
DetectEngineInspectDnsQuery, NULL);
DetectBufferTypeSetDescriptionByName("dns_query",
"dns request query");
g_dns_query_buffer_id = DetectBufferTypeGetByName("dns_query");
#ifdef HAVE_LUA
/* register these generic engines from here for now */
DetectAppLayerInspectEngineRegister2(
"dns_request", ALPROTO_DNS, SIG_FLAG_TOSERVER, 1, DetectEngineInspectDnsRequest, NULL);
DetectAppLayerInspectEngineRegister2("dns_response", ALPROTO_DNS, SIG_FLAG_TOCLIENT, 1,
DetectEngineInspectDnsResponse, NULL);
DetectBufferTypeSetDescriptionByName("dns_request",
"dns requests");
DetectBufferTypeSetDescriptionByName("dns_response",
"dns responses");
#endif
}
/**
* \brief setup the dns_query sticky buffer 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, const char *str)
{
if (DetectBufferSetActiveList(s, g_dns_query_buffer_id) < 0)
return -1;
if (DetectSignatureSetAppProto(s, ALPROTO_DNS) < 0)
return -1;
return 0;
}
#ifdef UNITTESTS
#include "detect-isdataat.h"
/** \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, };
Flow f;
void *dns_state = NULL;
Packet *p = NULL;
Signature *s = NULL;
ThreadVars tv;
DetectEngineThreadCtx *det_ctx = NULL;
AppLayerParserThreadCtx *alp_tctx = AppLayerParserThreadCtxAlloc();
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;
f.protomap = FlowGetProtoMapping(f.proto);
p->flow = &f;
p->flags |= PKT_HAS_FLOW;
p->flowflags |= FLOW_PKT_TOSERVER;
f.alproto = ALPROTO_DNS;
DetectEngineCtx *de_ctx = DetectEngineCtxInit();
FAIL_IF_NULL(de_ctx);
de_ctx->mpm_matcher = mpm_default_matcher;
de_ctx->flags |= DE_QUIET;
s = DetectEngineAppendSig(de_ctx, "alert dns any any -> any any "
"(msg:\"Test dns_query option\"; "
"dns_query; content:\"google\"; nocase; sid:1;)");
FAIL_IF_NULL(s);
SigGroupBuild(de_ctx);
DetectEngineThreadCtxInit(&tv, (void *)de_ctx, (void *)&det_ctx);
FLOWLOCK_WRLOCK(&f);
int r = AppLayerParserParse(NULL, alp_tctx, &f, ALPROTO_DNS,
STREAM_TOSERVER, buf, sizeof(buf));
if (r != 0) {
printf("toserver chunk 1 returned %" PRId32 ", expected 0: ", r);
FLOWLOCK_UNLOCK(&f);
FAIL;
}
FLOWLOCK_UNLOCK(&f);
dns_state = f.alstate;
FAIL_IF_NULL(dns_state);
/* do detect */
SigMatchSignatures(&tv, de_ctx, det_ctx, p);
if (!(PacketAlertCheck(p, 1))) {
printf("sig 1 didn't alert, but it should have: ");
FAIL;
}
if (alp_tctx != NULL)
AppLayerParserThreadCtxFree(alp_tctx);
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);
PASS;
}
/** \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, recursion 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, };
Flow f;
void *dns_state = NULL;
Packet *p1 = NULL, *p2 = NULL, *p3 = NULL;
Signature *s = NULL;
ThreadVars tv;
DetectEngineThreadCtx *det_ctx = NULL;
AppLayerParserThreadCtx *alp_tctx = AppLayerParserThreadCtxAlloc();
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.protomap = FlowGetProtoMapping(f.proto);
f.alproto = ALPROTO_DNS;
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();
FAIL_IF_NULL(de_ctx);
de_ctx->mpm_matcher = mpm_default_matcher;
de_ctx->flags |= DE_QUIET;
s = DetectEngineAppendSig(de_ctx, "alert dns any any -> any any "
"(msg:\"Test dns_query option\"; "
"dns_query; content:\"google.com\"; nocase; sid:1;)");
FAIL_IF_NULL(s);
s = DetectEngineAppendSig(de_ctx, "alert dns any any -> any any "
"(msg:\"Test dns_query option\"; "
"dns_query; content:\"google.net\"; nocase; sid:2;)");
FAIL_IF_NULL(s);
SigGroupBuild(de_ctx);
DetectEngineThreadCtxInit(&tv, (void *)de_ctx, (void *)&det_ctx);
FLOWLOCK_WRLOCK(&f);
int r = AppLayerParserParse(NULL, alp_tctx, &f, ALPROTO_DNS,
STREAM_TOSERVER, buf1, sizeof(buf1));
if (r != 0) {
printf("toserver chunk 1 returned %" PRId32 ", expected 0: ", r);
FLOWLOCK_UNLOCK(&f);
FAIL;
}
FLOWLOCK_UNLOCK(&f);
dns_state = f.alstate;
FAIL_IF_NULL(dns_state);
/* do detect */
SigMatchSignatures(&tv, de_ctx, det_ctx, p1);
if (!(PacketAlertCheck(p1, 1))) {
printf("(p1) sig 1 didn't alert, but it should have: ");
FAIL;
}
if (PacketAlertCheck(p1, 2)) {
printf("(p1) sig 2 did alert, but it should not have: ");
FAIL;
}
FLOWLOCK_WRLOCK(&f);
r = AppLayerParserParse(NULL, alp_tctx, &f, ALPROTO_DNS, STREAM_TOCLIENT,
buf2, sizeof(buf2));
if (r != 0) {
printf("toserver client 1 returned %" PRId32 ", expected 0: ", r);
FLOWLOCK_UNLOCK(&f);
FAIL;
}
FLOWLOCK_UNLOCK(&f);
/* do detect */
SigMatchSignatures(&tv, de_ctx, det_ctx, p2);
if (PacketAlertCheck(p2, 1)) {
printf("(p2) sig 1 alerted, but it should not have: ");
FAIL;
}
if (PacketAlertCheck(p2, 2)) {
printf("(p2) sig 2 alerted, but it should not have: ");
FAIL;
}
FLOWLOCK_WRLOCK(&f);
r = AppLayerParserParse(NULL, alp_tctx, &f, ALPROTO_DNS, STREAM_TOSERVER,
buf3, sizeof(buf3));
if (r != 0) {
printf("toserver chunk 3 returned %" PRId32 ", expected 0: ", r);
FLOWLOCK_UNLOCK(&f);
FAIL;
}
FLOWLOCK_UNLOCK(&f);
/* do detect */
SigMatchSignatures(&tv, de_ctx, det_ctx, p3);
if (PacketAlertCheck(p3, 1)) {
printf("(p3) sig 1 alerted, but it should not have: ");
FAIL;
}
if (!(PacketAlertCheck(p3, 2))) {
printf("(p3) sig 2 didn't alert, but it should have: ");
FAIL;
}
if (alp_tctx != NULL)
AppLayerParserThreadCtxFree(alp_tctx);
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);
PASS;
}
/** \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, };
Flow f;
void *dns_state = NULL;
Packet *p = NULL;
Signature *s = NULL;
ThreadVars tv;
DetectEngineThreadCtx *det_ctx = NULL;
TcpSession ssn;
AppLayerParserThreadCtx *alp_tctx = AppLayerParserThreadCtxAlloc();
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;
f.protomap = FlowGetProtoMapping(f.proto);
p->flow = &f;
p->flags |= PKT_HAS_FLOW|PKT_STREAM_EST;
p->flowflags |= FLOW_PKT_TOSERVER|FLOW_PKT_ESTABLISHED;
f.alproto = ALPROTO_DNS;
StreamTcpInitConfig(true);
DetectEngineCtx *de_ctx = DetectEngineCtxInit();
FAIL_IF_NULL(de_ctx);
de_ctx->mpm_matcher = mpm_default_matcher;
de_ctx->flags |= DE_QUIET;
s = DetectEngineAppendSig(de_ctx, "alert dns any any -> any any "
"(msg:\"Test dns_query option\"; "
"dns_query; content:\"google\"; nocase; sid:1;)");
FAIL_IF_NULL(s);
SigGroupBuild(de_ctx);
DetectEngineThreadCtxInit(&tv, (void *)de_ctx, (void *)&det_ctx);
FLOWLOCK_WRLOCK(&f);
int r = AppLayerParserParse(NULL, alp_tctx, &f, ALPROTO_DNS,
STREAM_TOSERVER, buf, sizeof(buf));
if (r != 0) {
printf("toserver chunk 1 returned %" PRId32 ", expected 0: ", r);
FLOWLOCK_UNLOCK(&f);
FAIL;
}
FLOWLOCK_UNLOCK(&f);
dns_state = f.alstate;
FAIL_IF_NULL(dns_state);
/* do detect */
SigMatchSignatures(&tv, de_ctx, det_ctx, p);
if (!(PacketAlertCheck(p, 1))) {
printf("sig 1 didn't alert, but it should have: ");
FAIL;
}
if (alp_tctx != NULL)
AppLayerParserThreadCtxFree(alp_tctx);
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);
PASS;
}
/** \test simple google.com query matching, pcre */
static int DetectDnsQueryTest04(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, };
Flow f;
void *dns_state = NULL;
Packet *p = NULL;
Signature *s = NULL;
ThreadVars tv;
DetectEngineThreadCtx *det_ctx = NULL;
AppLayerParserThreadCtx *alp_tctx = AppLayerParserThreadCtxAlloc();
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;
f.protomap = FlowGetProtoMapping(f.proto);
p->flow = &f;
p->flags |= PKT_HAS_FLOW;
p->flowflags |= FLOW_PKT_TOSERVER;
f.alproto = ALPROTO_DNS;
DetectEngineCtx *de_ctx = DetectEngineCtxInit();
FAIL_IF_NULL(de_ctx);
de_ctx->mpm_matcher = mpm_default_matcher;
de_ctx->flags |= DE_QUIET;
s = DetectEngineAppendSig(de_ctx, "alert dns any any -> any any "
"(msg:\"Test dns_query option\"; "
"dns_query; content:\"google\"; nocase; "
"pcre:\"/google\\.com$/i\"; sid:1;)");
FAIL_IF_NULL(s);
s = DetectEngineAppendSig(de_ctx, "alert dns any any -> any any "
"(msg:\"Test dns_query option\"; "
"dns_query; content:\"google\"; nocase; "
"pcre:\"/^\\.[a-z]{2,3}$/iR\"; sid:2;)");
FAIL_IF_NULL(s);
SigGroupBuild(de_ctx);
DetectEngineThreadCtxInit(&tv, (void *)de_ctx, (void *)&det_ctx);
FLOWLOCK_WRLOCK(&f);
int r = AppLayerParserParse(NULL, alp_tctx, &f, ALPROTO_DNS,
STREAM_TOSERVER, buf, sizeof(buf));
if (r != 0) {
printf("toserver chunk 1 returned %" PRId32 ", expected 0: ", r);
FLOWLOCK_UNLOCK(&f);
FAIL;
}
FLOWLOCK_UNLOCK(&f);
dns_state = f.alstate;
FAIL_IF_NULL(dns_state);
/* do detect */
SigMatchSignatures(&tv, de_ctx, det_ctx, p);
if (!(PacketAlertCheck(p, 1))) {
printf("sig 1 didn't alert, but it should have: ");
FAIL;
}
if (!(PacketAlertCheck(p, 2))) {
printf("sig 2 didn't alert, but it should have: ");
FAIL;
}
if (alp_tctx != NULL)
AppLayerParserThreadCtxFree(alp_tctx);
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);
PASS;
}
/** \test multi tx google.(com|net) query matching +
* app layer event */
static int DetectDnsQueryTest05(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, recursion 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, };
Flow f;
void *dns_state = NULL;
Packet *p1 = NULL, *p2 = NULL, *p3 = NULL;
Signature *s = NULL;
ThreadVars tv;
DetectEngineThreadCtx *det_ctx = NULL;
AppLayerParserThreadCtx *alp_tctx = AppLayerParserThreadCtxAlloc();
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.protomap = FlowGetProtoMapping(f.proto);
f.alproto = ALPROTO_DNS;
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();
FAIL_IF_NULL(de_ctx);
de_ctx->mpm_matcher = mpm_default_matcher;
de_ctx->flags |= DE_QUIET;
s = DetectEngineAppendSig(de_ctx, "alert dns any any -> any any "
"(msg:\"Test dns_query option\"; "
"dns_query; content:\"google.com\"; nocase; sid:1;)");
FAIL_IF_NULL(s);
s = DetectEngineAppendSig(de_ctx, "alert dns any any -> any any "
"(msg:\"Test dns_query option\"; "
"dns_query; content:\"google.net\"; nocase; sid:2;)");
FAIL_IF_NULL(s);
s = DetectEngineAppendSig(de_ctx, "alert dns any any -> any any "
"(msg:\"Test Z flag event\"; "
"app-layer-event:dns.z_flag_set; sid:3;)");
FAIL_IF_NULL(s);
SigGroupBuild(de_ctx);
DetectEngineThreadCtxInit(&tv, (void *)de_ctx, (void *)&det_ctx);
FLOWLOCK_WRLOCK(&f);
int r = AppLayerParserParse(NULL, alp_tctx, &f, ALPROTO_DNS,
STREAM_TOSERVER, buf1, sizeof(buf1));
if (r != 0) {
printf("toserver chunk 1 returned %" PRId32 ", expected 0: ", r);
FLOWLOCK_UNLOCK(&f);
FAIL;
}
FLOWLOCK_UNLOCK(&f);
dns_state = f.alstate;
FAIL_IF_NULL(dns_state);
/* do detect */
SigMatchSignatures(&tv, de_ctx, det_ctx, p1);
if (!(PacketAlertCheck(p1, 1))) {
printf("(p1) sig 1 didn't alert, but it should have: ");
FAIL;
}
if (PacketAlertCheck(p1, 2)) {
printf("(p1) sig 2 did alert, but it should not have: ");
FAIL;
}
FLOWLOCK_WRLOCK(&f);
r = AppLayerParserParse(NULL, alp_tctx, &f, ALPROTO_DNS, STREAM_TOCLIENT,
buf2, sizeof(buf2));
if (r != 0) {
printf("toserver client 1 returned %" PRId32 ", expected 0\n", r);
FLOWLOCK_UNLOCK(&f);
FAIL;
}
FLOWLOCK_UNLOCK(&f);
/* do detect */
SigMatchSignatures(&tv, de_ctx, det_ctx, p2);
if (PacketAlertCheck(p2, 1)) {
printf("(p2) sig 1 alerted, but it should not have: ");
FAIL;
}
if (PacketAlertCheck(p2, 2)) {
printf("(p2) sig 2 alerted, but it should not have: ");
FAIL;
}
if (!(PacketAlertCheck(p2, 3))) {
printf("(p2) sig 3 didn't alert, but it should have: ");
FAIL;
}
FLOWLOCK_WRLOCK(&f);
r = AppLayerParserParse(NULL, alp_tctx, &f, ALPROTO_DNS, STREAM_TOSERVER,
buf3, sizeof(buf3));
if (r != 0) {
printf("toserver chunk 3 returned %" PRId32 ", expected 0: ", r);
FLOWLOCK_UNLOCK(&f);
FAIL;
}
FLOWLOCK_UNLOCK(&f);
/* do detect */
SigMatchSignatures(&tv, de_ctx, det_ctx, p3);
if (PacketAlertCheck(p3, 1)) {
printf("(p3) sig 1 alerted, but it should not have: ");
FAIL;
}
if (!(PacketAlertCheck(p3, 2))) {
printf("(p3) sig 2 didn't alert, but it should have: ");
FAIL;
}
/** \todo should not alert, bug #839
if (PacketAlertCheck(p3, 3)) {
printf("(p3) sig 3 did alert, but it should not have: ");
goto end;
}
*/
if (alp_tctx != NULL)
AppLayerParserThreadCtxFree(alp_tctx);
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);
PASS;
}
static int DetectDnsQueryIsdataatParseTest(void)
{
DetectEngineCtx *de_ctx = DetectEngineCtxInit();
FAIL_IF_NULL(de_ctx);
de_ctx->flags |= DE_QUIET;
Signature *s = DetectEngineAppendSig(de_ctx,
"alert dns any any -> any any ("
"dns_query; content:\"one\"; "
"isdataat:!4,relative; sid:1;)");
FAIL_IF_NULL(s);
SigMatch *sm = s->init_data->smlists_tail[g_dns_query_buffer_id];
FAIL_IF_NULL(sm);
FAIL_IF_NOT(sm->type == DETECT_ISDATAAT);
DetectIsdataatData *data = (DetectIsdataatData *)sm->ctx;
FAIL_IF_NOT(data->flags & ISDATAAT_RELATIVE);
FAIL_IF_NOT(data->flags & ISDATAAT_NEGATED);
FAIL_IF(data->flags & ISDATAAT_RAWBYTES);
DetectEngineCtxFree(de_ctx);
PASS;
}
static void DetectDnsQueryRegisterTests(void)
{
UtRegisterTest("DetectDnsQueryTest01", DetectDnsQueryTest01);
UtRegisterTest("DetectDnsQueryTest02", DetectDnsQueryTest02);
UtRegisterTest("DetectDnsQueryTest03 -- tcp", DetectDnsQueryTest03);
UtRegisterTest("DetectDnsQueryTest04 -- pcre", DetectDnsQueryTest04);
UtRegisterTest("DetectDnsQueryTest05 -- app layer event",
DetectDnsQueryTest05);
UtRegisterTest("DetectDnsQueryIsdataatParseTest",
DetectDnsQueryIsdataatParseTest);
}
#endif