detect: add (mpm) keyword ja3s.string

Match on JA3S string using ja3s.string keyword, e.g:

  alert tls any any -> any any (msg:"ja3s.string test";
      ja3s.string; content:"10-11-12"; sid:1;)

diff --git a/src/Makefile.am b/src/Makefile.am
index 40750b866c4bf6cdd97190dde2ae3b8ed66645a6..23f8c1371866dcdd8cb29ae989622b15d5e69537 100644 (file)
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -108,6 +108,7 @@ detect-dns-query.c detect-dns-query.h \
 detect-tls-ja3-hash.c detect-tls-ja3-hash.h \
 detect-tls-ja3-string.c detect-tls-ja3-string.h \
 detect-tls-ja3s-hash.c detect-tls-ja3s-hash.h \
+detect-tls-ja3s-string.c detect-tls-ja3s-string.h \
 detect-tls-sni.c detect-tls-sni.h \
 detect-tls-cert-issuer.c detect-tls-cert-issuer.h \
 detect-tls-cert-subject.c detect-tls-cert-subject.h \

diff --git a/src/detect-engine-register.c b/src/detect-engine-register.c
index f8a6acc1e00fccaa428d7ca795a8e1e9e259ac79..e104114e69b31e9938d926e83dfaebb17ebd9b5d 100644 (file)
--- a/src/detect-engine-register.c
+++ b/src/detect-engine-register.c
@@ -55,6 +55,7 @@
 #include "detect-tls-ja3-hash.h"
 #include "detect-tls-ja3-string.h"
 #include "detect-tls-ja3s-hash.h"
+#include "detect-tls-ja3s-string.h"
 #include "detect-engine-state.h"
 #include "detect-engine-analyzer.h"
 
@@ -439,6 +440,7 @@ void SigTableSetup(void)
     DetectTlsJa3HashRegister();
     DetectTlsJa3StringRegister();
     DetectTlsJa3SHashRegister();
+    DetectTlsJa3SStringRegister();
 
     DetectAppLayerEventRegister();
     /* end of order dependent regs */

diff --git a/src/detect-engine-register.h b/src/detect-engine-register.h
index ff725cceab5bbceea25029c2d38da14a1d06a822..bca55bfbe6a0db4c0b43ea85ebfea0d27cd4771f 100644 (file)
--- a/src/detect-engine-register.h
+++ b/src/detect-engine-register.h
@@ -203,6 +203,7 @@ enum {
     DETECT_AL_TLS_JA3_HASH,
     DETECT_AL_TLS_JA3_STRING,
     DETECT_AL_TLS_JA3S_HASH,
+    DETECT_AL_TLS_JA3S_STRING,
 
     DETECT_AL_MODBUS,
     DETECT_CIPSERVICE,

diff --git a/src/detect-tls-ja3s-string.c b/src/detect-tls-ja3s-string.c
new file mode 100644 (file)
index 0000000..0587da6
--- /dev/null
+++ b/src/detect-tls-ja3s-string.c
@@ -0,0 +1,300 @@
+/* Copyright (C) 2019 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 Mats Klepsland <mats.klepsland@gmail.com>
+ *
+ * Implements support for ja3s.string keyword.
+ */
+
+#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-content.h"
+#include "detect-pcre.h"
+#include "detect-tls-ja3s-string.h"
+
+#include "flow.h"
+#include "flow-util.h"
+#include "flow-var.h"
+
+#include "conf.h"
+#include "conf-yaml-loader.h"
+
+#include "util-debug.h"
+#include "util-unittest.h"
+#include "util-spm.h"
+#include "util-print.h"
+#include "util-ja3.h"
+
+#include "stream-tcp.h"
+
+#include "app-layer.h"
+#include "app-layer-ssl.h"
+
+#include "util-unittest.h"
+#include "util-unittest-helper.h"
+
+static int DetectTlsJa3SStringSetup(DetectEngineCtx *, Signature *, const char *);
+static void DetectTlsJa3SStringRegisterTests(void);
+static InspectionBuffer *GetData(DetectEngineThreadCtx *det_ctx,
+       const DetectEngineTransforms *transforms,
+       Flow *f, const uint8_t flow_flags,
+       void *txv, const int list_id);
+static int g_tls_ja3s_str_buffer_id = 0;
+
+/**
+ * \brief Registration function for keyword: ja3s.string
+ */
+void DetectTlsJa3SStringRegister(void)
+{
+    sigmatch_table[DETECT_AL_TLS_JA3S_STRING].name = "ja3s.string";
+    sigmatch_table[DETECT_AL_TLS_JA3S_STRING].desc = "content modifier to match the JA3S string sticky buffer";
+    sigmatch_table[DETECT_AL_TLS_JA3S_STRING].url = DOC_URL DOC_VERSION "/rules/ja3-keywords.html#ja3s-string";
+    sigmatch_table[DETECT_AL_TLS_JA3S_STRING].Setup = DetectTlsJa3SStringSetup;
+    sigmatch_table[DETECT_AL_TLS_JA3S_STRING].RegisterTests = DetectTlsJa3SStringRegisterTests;
+
+    sigmatch_table[DETECT_AL_TLS_JA3S_STRING].flags |= SIGMATCH_NOOPT;
+    sigmatch_table[DETECT_AL_TLS_JA3S_STRING].flags |= SIGMATCH_INFO_STICKY_BUFFER;
+
+    DetectAppLayerInspectEngineRegister2("ja3s.string", ALPROTO_TLS, SIG_FLAG_TOCLIENT, 0,
+            DetectEngineInspectBufferGeneric, GetData);
+
+    DetectAppLayerMpmRegister2("ja3s.string", SIG_FLAG_TOCLIENT, 2,
+            PrefilterGenericMpmRegister, GetData, ALPROTO_TLS, 0);
+
+    DetectBufferTypeSetDescriptionByName("ja3s.string", "TLS JA3S string");
+
+    g_tls_ja3s_str_buffer_id = DetectBufferTypeGetByName("ja3s.string");
+}
+
+/**
+ * \brief this function setup the ja3s.string 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 DetectTlsJa3SStringSetup(DetectEngineCtx *de_ctx, Signature *s, const char *str)
+{
+    if (DetectBufferSetActiveList(s, g_tls_ja3s_str_buffer_id) < 0)
+        return -1;
+
+    if (DetectSignatureSetAppProto(s, ALPROTO_TLS) < 0)
+        return -1;
+
+    /* Check if JA3 is disabled */
+    if (!RunmodeIsUnittests() && Ja3IsDisabled("rule"))
+        return -1;
+
+    return 0;
+}
+
+static InspectionBuffer *GetData(DetectEngineThreadCtx *det_ctx,
+        const DetectEngineTransforms *transforms, Flow *f,
+        const uint8_t flow_flags, void *txv, const int list_id)
+{
+    InspectionBuffer *buffer = InspectionBufferGet(det_ctx, list_id);
+    if (buffer->inspect == NULL) {
+        const SSLState *ssl_state = (SSLState *)f->alstate;
+
+        if (ssl_state->server_connp.ja3_str == NULL ||
+                ssl_state->server_connp.ja3_str->data == NULL) {
+            return NULL;
+        }
+
+        const uint32_t data_len = strlen(ssl_state->server_connp.ja3_str->data);
+        const uint8_t *data = (uint8_t *)ssl_state->server_connp.ja3_str->data;
+
+        InspectionBufferSetup(buffer, data, data_len);
+        InspectionBufferApplyTransforms(buffer, transforms);
+    }
+
+    return buffer;
+}
+
+#ifndef HAVE_NSS
+
+static void DetectTlsJa3SStringRegisterTests(void)
+{
+    /* Don't register any tests */
+}
+
+#else /* HAVE_NSS */
+
+#ifdef UNITTESTS
+
+/**
+ * \test Test matching on a simple client hello packet
+ */
+static int DetectTlsJa3SStringTest01(void)
+{
+    /* client hello */
+    uint8_t client_hello[] = {
+            0x16, 0x03, 0x01, 0x00, 0xc8, 0x01, 0x00, 0x00,
+            0xc4, 0x03, 0x03, 0xd6, 0x08, 0x5a, 0xa2, 0x86,
+            0x5b, 0x85, 0xd4, 0x40, 0xab, 0xbe, 0xc0, 0xbc,
+            0x41, 0xf2, 0x26, 0xf0, 0xfe, 0x21, 0xee, 0x8b,
+            0x4c, 0x7e, 0x07, 0xc8, 0xec, 0xd2, 0x00, 0x46,
+            0x4c, 0xeb, 0xb7, 0x00, 0x00, 0x16, 0xc0, 0x2b,
+            0xc0, 0x2f, 0xc0, 0x0a, 0xc0, 0x09, 0xc0, 0x13,
+            0xc0, 0x14, 0x00, 0x33, 0x00, 0x39, 0x00, 0x2f,
+            0x00, 0x35, 0x00, 0x0a, 0x01, 0x00, 0x00, 0x85,
+            0x00, 0x00, 0x00, 0x12, 0x00, 0x10, 0x00, 0x00,
+            0x0d, 0x77, 0x77, 0x77, 0x2e, 0x67, 0x6f, 0x6f,
+            0x67, 0x6c, 0x65, 0x2e, 0x6e, 0x6f, 0xff, 0x01,
+            0x00, 0x01, 0x00, 0x00, 0x0a, 0x00, 0x08, 0x00,
+            0x06, 0x00, 0x17, 0x00, 0x18, 0x00, 0x19, 0x00,
+            0x0b, 0x00, 0x02, 0x01, 0x00, 0x00, 0x23, 0x00,
+            0x00, 0x33, 0x74, 0x00, 0x00, 0x00, 0x10, 0x00,
+            0x29, 0x00, 0x27, 0x05, 0x68, 0x32, 0x2d, 0x31,
+            0x36, 0x05, 0x68, 0x32, 0x2d, 0x31, 0x35, 0x05,
+            0x68, 0x32, 0x2d, 0x31, 0x34, 0x02, 0x68, 0x32,
+            0x08, 0x73, 0x70, 0x64, 0x79, 0x2f, 0x33, 0x2e,
+            0x31, 0x08, 0x68, 0x74, 0x74, 0x70, 0x2f, 0x31,
+            0x2e, 0x31, 0x00, 0x05, 0x00, 0x05, 0x01, 0x00,
+            0x00, 0x00, 0x00, 0x00, 0x0d, 0x00, 0x16, 0x00,
+            0x14, 0x04, 0x01, 0x05, 0x01, 0x06, 0x01, 0x02,
+            0x01, 0x04, 0x03, 0x05, 0x03, 0x06, 0x03, 0x02,
+            0x03, 0x04, 0x02, 0x02, 0x02
+    };
+
+    /* server hello */
+    uint8_t server_hello[] = {
+            0x16, 0x03, 0x03, 0x00, 0x48, 0x02, 0x00, 0x00,
+            0x44, 0x03, 0x03, 0x57, 0x91, 0xb8, 0x63, 0xdd,
+            0xdb, 0xbb, 0x23, 0xcf, 0x0b, 0x43, 0x02, 0x1d,
+            0x46, 0x11, 0x27, 0x5c, 0x98, 0xcf, 0x67, 0xe1,
+            0x94, 0x3d, 0x62, 0x7d, 0x38, 0x48, 0x21, 0x23,
+            0xa5, 0x62, 0x31, 0x00, 0xc0, 0x2f, 0x00, 0x00,
+            0x1c, 0xff, 0x01, 0x00, 0x01, 0x00, 0x00, 0x00,
+            0x00, 0x00, 0x00, 0x23, 0x00, 0x00, 0x00, 0x10,
+            0x00, 0x05, 0x00, 0x03, 0x02, 0x68, 0x32, 0x00,
+            0x0b, 0x00, 0x02, 0x01, 0x00
+    };
+
+    Flow f;
+    SSLState *ssl_state = NULL;
+    TcpSession ssn;
+    Packet *p1 = NULL;
+    Packet *p2 = NULL;
+    ThreadVars tv;
+    DetectEngineThreadCtx *det_ctx = NULL;
+    AppLayerParserThreadCtx *alp_tctx = AppLayerParserThreadCtxAlloc();
+
+    memset(&tv, 0, sizeof(ThreadVars));
+    memset(&f, 0, sizeof(Flow));
+    memset(&ssn, 0, sizeof(TcpSession));
+
+    p1 = UTHBuildPacketReal(client_hello, sizeof(client_hello), IPPROTO_TCP,
+                            "192.168.1.5", "192.168.1.1", 51251, 443);
+    p2 = UTHBuildPacketReal(server_hello, sizeof(server_hello), IPPROTO_TCP,
+                            "192.168.1.1", "192.168.1.5", 443, 51251);
+
+    FLOW_INITIALIZE(&f);
+    f.flags |= FLOW_IPV4;
+    f.proto = IPPROTO_TCP;
+    f.protomap = FlowGetProtoMapping(f.proto);
+    f.alproto = ALPROTO_TLS;
+
+    p1->flow = &f;
+    p1->flags |= PKT_HAS_FLOW | PKT_STREAM_EST;
+    p1->flowflags |= FLOW_PKT_TOSERVER;
+    p1->flowflags |= FLOW_PKT_ESTABLISHED;
+    p1->pcap_cnt = 1;
+
+    p2->flow = &f;
+    p2->flags |= PKT_HAS_FLOW | PKT_STREAM_EST;
+    p2->flowflags |= FLOW_PKT_TOCLIENT;
+    p2->flowflags |= FLOW_PKT_ESTABLISHED;
+    p2->pcap_cnt = 2;
+
+    StreamTcpInitConfig(TRUE);
+
+    DetectEngineCtx *de_ctx = DetectEngineCtxInit();
+    FAIL_IF_NULL(de_ctx);
+
+    de_ctx->mpm_matcher = mpm_default_matcher;
+    de_ctx->flags |= DE_QUIET;
+
+    Signature *s = DetectEngineAppendSig(de_ctx, "alert tls any any -> any any "
+                                "(msg:\"Test ja3s_hash\"; "
+                                "ja3s.string; "
+                                "content:\"771,49199,65281-0-35-16-11\"; "
+                                "sid:1;)");
+    FAIL_IF_NULL(s);
+
+    SigGroupBuild(de_ctx);
+    DetectEngineThreadCtxInit(&tv, (void *)de_ctx, (void *)&det_ctx);
+
+    int r = AppLayerParserParse(NULL, alp_tctx, &f, ALPROTO_TLS,
+                                STREAM_TOSERVER, client_hello,
+                                sizeof(client_hello));
+
+    FAIL_IF(r != 0);
+
+    ssl_state = f.alstate;
+    FAIL_IF_NULL(ssl_state);
+
+    SigMatchSignatures(&tv, de_ctx, det_ctx, p1);
+
+    FAIL_IF(PacketAlertCheck(p1, 1));
+
+    r = AppLayerParserParse(NULL, alp_tctx, &f, ALPROTO_TLS, STREAM_TOCLIENT,
+                            server_hello, sizeof(server_hello));
+
+    FAIL_IF(r != 0);
+
+    FAIL_IF_NULL(ssl_state->server_connp.ja3_str);
+
+    SigMatchSignatures(&tv, de_ctx, det_ctx, p2);
+
+    FAIL_IF_NOT(PacketAlertCheck(p2, 1));
+
+    AppLayerParserThreadCtxFree(alp_tctx);
+    DetectEngineThreadCtxDeinit(&tv, det_ctx);
+    DetectEngineCtxFree(de_ctx);
+    StreamTcpFreeConfig(TRUE);
+    FLOW_DESTROY(&f);
+    UTHFreePacket(p1);
+    UTHFreePacket(p2);
+
+    PASS;
+}
+
+#endif /* UNITTESTS */
+
+static void DetectTlsJa3SStringRegisterTests(void)
+{
+#ifdef UNITTESTS
+    UtRegisterTest("DetectTlsJa3SStringTest01", DetectTlsJa3SStringTest01);
+#endif /* UNITTESTS */
+}
+
+#endif /* HAVE_NSS */

diff --git a/src/detect-tls-ja3s-string.h b/src/detect-tls-ja3s-string.h
new file mode 100644 (file)
index 0000000..25a57aa
--- /dev/null
+++ b/src/detect-tls-ja3s-string.h
@@ -0,0 +1,30 @@
+/* Copyright (C) 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.
+ */
+
+/**
+ * \file
+ *
+ * \author Mats Klepsland <mats.klepsland@gmail.com>
+ */
+
+#ifndef __DETECT_TLS_JA3S_STRING_H__
+#define __DETECT_TLS_JA3S_STRING_H__
+
+/* Prototypes */
+void DetectTlsJa3SStringRegister(void);
+
+#endif /* __DETECT_TLS_JA3S_STRING_H__ */