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-rw-r--r--framework/src/suricata/src/detect-ack.c302
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diff --git a/framework/src/suricata/src/detect-ack.c b/framework/src/suricata/src/detect-ack.c
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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 Brian Rectanus <brectanu@gmail.com>
+ *
+ * Implements the "ack" keyword.
+ */
+
+#include "suricata-common.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-ack.h"
+
+#include "util-byte.h"
+#include "util-unittest.h"
+#include "util-unittest-helper.h"
+#include "util-debug.h"
+
+/* prototypes */
+static int DetectAckSetup(DetectEngineCtx *, Signature *, char *);
+static int DetectAckMatch(ThreadVars *, DetectEngineThreadCtx *,
+ Packet *, Signature *, const SigMatchCtx *);
+static void DetectAckRegisterTests(void);
+static void DetectAckFree(void *);
+
+void DetectAckRegister(void)
+{
+ sigmatch_table[DETECT_ACK].name = "ack";
+ sigmatch_table[DETECT_ACK].desc = "check for a specific TCP acknowledgement number";
+ sigmatch_table[DETECT_ACK].url = "https://redmine.openinfosecfoundation.org/projects/suricata/wiki/Header_keywords#ack";
+ sigmatch_table[DETECT_ACK].Match = DetectAckMatch;
+ sigmatch_table[DETECT_ACK].Setup = DetectAckSetup;
+ sigmatch_table[DETECT_ACK].Free = DetectAckFree;
+ sigmatch_table[DETECT_ACK].RegisterTests = DetectAckRegisterTests;
+}
+
+/**
+ * \internal
+ * \brief This function is used to match packets with a given Ack number
+ *
+ * \param t pointer to thread vars
+ * \param det_ctx pointer to the pattern matcher thread
+ * \param p pointer to the current packet
+ * \param m pointer to the sigmatch that we will cast into DetectAckData
+ *
+ * \retval 0 no match
+ * \retval 1 match
+ */
+static int DetectAckMatch(ThreadVars *t, DetectEngineThreadCtx *det_ctx,
+ Packet *p, Signature *s, const SigMatchCtx *ctx)
+{
+ const DetectAckData *data = (const DetectAckData *)ctx;
+
+ /* This is only needed on TCP packets */
+ if (!(PKT_IS_TCP(p)) || PKT_IS_PSEUDOPKT(p)) {
+ return 0;
+ }
+
+ return (data->ack == TCP_GET_ACK(p)) ? 1 : 0;
+}
+
+/**
+ * \internal
+ * \brief this function is used to add the ack option into the signature
+ *
+ * \param de_ctx pointer to the Detection Engine Context
+ * \param s pointer to the Current Signature
+ * \param m pointer to the Current SigMatch
+ * \param optstr pointer to the user provided options
+ *
+ * \retval 0 on Success
+ * \retval -1 on Failure
+ */
+static int DetectAckSetup(DetectEngineCtx *de_ctx, Signature *s, char *optstr)
+{
+ DetectAckData *data = NULL;
+ SigMatch *sm = NULL;
+
+ data = SCMalloc(sizeof(DetectAckData));
+ if (unlikely(data == NULL))
+ goto error;
+
+ sm = SigMatchAlloc();
+ if (sm == NULL)
+ goto error;
+
+ sm->type = DETECT_ACK;
+
+ if (-1 == ByteExtractStringUint32(&data->ack, 10, 0, optstr)) {
+ goto error;
+ }
+ sm->ctx = (SigMatchCtx*)data;
+
+ SigMatchAppendSMToList(s, sm, DETECT_SM_LIST_MATCH);
+ s->flags |= SIG_FLAG_REQUIRE_PACKET;
+
+ return 0;
+
+error:
+ if (data)
+ SCFree(data);
+ if (sm)
+ SigMatchFree(sm);
+ return -1;
+
+}
+
+/**
+ * \internal
+ * \brief this function will free memory associated with ack option
+ *
+ * \param data pointer to ack configuration data
+ */
+static void DetectAckFree(void *ptr)
+{
+ DetectAckData *data = (DetectAckData *)ptr;
+ SCFree(data);
+}
+
+
+#ifdef UNITTESTS
+/**
+ * \internal
+ * \brief This test tests sameip success and failure.
+ */
+static int DetectAckSigTest01Real(int mpm_type)
+{
+ Packet *p1 = NULL;
+ Packet *p2 = NULL;
+ Packet *p3 = NULL;
+ ThreadVars th_v;
+ DetectEngineThreadCtx *det_ctx;
+ int result = 0;
+
+ memset(&th_v, 0, sizeof(th_v));
+
+ /* TCP w/ack=42 */
+ p1 = UTHBuildPacket(NULL, 0, IPPROTO_TCP);
+ p1->tcph->th_ack = htonl(42);
+
+ /* TCP w/ack=100 */
+ p2 = UTHBuildPacket(NULL, 0, IPPROTO_TCP);
+ p2->tcph->th_ack = htonl(100);
+
+ /* ICMP */
+ p3 = UTHBuildPacket(NULL, 0, IPPROTO_ICMP);
+
+ DetectEngineCtx *de_ctx = DetectEngineCtxInit();
+ if (de_ctx == NULL) {
+ goto end;
+ }
+
+ de_ctx->mpm_matcher = mpm_type;
+ de_ctx->flags |= DE_QUIET;
+
+ /* These three are crammed in here as there is no Parse */
+ if (SigInit(de_ctx,
+ "alert tcp any any -> any any "
+ "(msg:\"Testing ack\";ack:foo;sid:1;)") != NULL)
+ {
+ printf("invalid ack accepted: ");
+ goto cleanup_engine;
+ }
+ if (SigInit(de_ctx,
+ "alert tcp any any -> any any "
+ "(msg:\"Testing ack\";ack:9999999999;sid:1;)") != NULL)
+ {
+ printf("overflowing ack accepted: ");
+ goto cleanup_engine;
+ }
+ if (SigInit(de_ctx,
+ "alert tcp any any -> any any "
+ "(msg:\"Testing ack\";ack:-100;sid:1;)") != NULL)
+ {
+ printf("negative ack accepted: ");
+ goto cleanup_engine;
+ }
+
+ de_ctx->sig_list = SigInit(de_ctx,
+ "alert tcp any any -> any any "
+ "(msg:\"Testing ack\";ack:41;sid:1;)");
+ if (de_ctx->sig_list == NULL) {
+ goto cleanup_engine;
+ }
+
+ de_ctx->sig_list->next = SigInit(de_ctx,
+ "alert tcp any any -> any any "
+ "(msg:\"Testing ack\";ack:42;sid:2;)");
+ if (de_ctx->sig_list->next == NULL) {
+ goto cleanup_engine;
+ }
+
+ SigGroupBuild(de_ctx);
+ DetectEngineThreadCtxInit(&th_v, (void *)de_ctx, (void *)&det_ctx);
+
+ SigMatchSignatures(&th_v, de_ctx, det_ctx, p1);
+ if (PacketAlertCheck(p1, 1) != 0) {
+ printf("sid 1 alerted, but should not have: ");
+ goto cleanup;
+ }
+ if (PacketAlertCheck(p1, 2) == 0) {
+ printf("sid 2 did not alert, but should have: ");
+ goto cleanup;
+ }
+
+ SigMatchSignatures(&th_v, de_ctx, det_ctx, p2);
+ if (PacketAlertCheck(p2, 1) != 0) {
+ printf("sid 1 alerted, but should not have: ");
+ goto cleanup;
+ }
+ if (PacketAlertCheck(p2, 2) != 0) {
+ printf("sid 2 alerted, but should not have: ");
+ goto cleanup;
+ }
+
+ SigMatchSignatures(&th_v, de_ctx, det_ctx, p3);
+ if (PacketAlertCheck(p3, 1) != 0) {
+ printf("sid 1 alerted, but should not have: ");
+ goto cleanup;
+ }
+ if (PacketAlertCheck(p3, 2) != 0) {
+ printf("sid 2 alerted, but should not have: ");
+ goto cleanup;
+ }
+
+ result = 1;
+
+cleanup:
+ SigGroupCleanup(de_ctx);
+ SigCleanSignatures(de_ctx);
+
+ DetectEngineThreadCtxDeinit(&th_v, (void *)det_ctx);
+
+cleanup_engine:
+ DetectEngineCtxFree(de_ctx);
+
+end:
+ return result;
+}
+
+/**
+ * \test DetectAckSigTest01B2g tests sameip under B2g MPM
+ */
+static int DetectAckSigTest01B2g(void)
+{
+ return DetectAckSigTest01Real(MPM_B2G);
+}
+
+/**
+ * \test DetectAckSigTest01B2g tests sameip under B3g MPM
+ */
+static int DetectAckSigTest01B3g(void)
+{
+ return DetectAckSigTest01Real(MPM_B3G);
+}
+
+/**
+ * \test DetectAckSigTest01B2g tests sameip under WuManber MPM
+ */
+static int DetectAckSigTest01Wm(void)
+{
+ return DetectAckSigTest01Real(MPM_WUMANBER);
+}
+
+#endif /* UNITTESTS */
+
+/**
+ * \internal
+ * \brief This function registers unit tests for DetectAck
+ */
+static void DetectAckRegisterTests(void)
+{
+#ifdef UNITTESTS
+ UtRegisterTest("DetectAckSigTest01B2g", DetectAckSigTest01B2g, 1);
+ UtRegisterTest("DetectAckSigTest01B3g", DetectAckSigTest01B3g, 1);
+ UtRegisterTest("DetectAckSigTest01Wm", DetectAckSigTest01Wm, 1);
+#endif /* UNITTESTS */
+}
+