detect/config: initial version

src/Makefile.am

@@ -104,6 +104,7 @@ detect-bytetest.c detect-bytetest.h \
 detect-bypass.c detect-bypass.h \
 detect.c detect.h \
 detect-classtype.c detect-classtype.h \
+detect-config.c detect-config.h \
 detect-content.c detect-content.h \
 detect-csum.c detect-csum.h \
 detect-datarep.c detect-datarep.h \

src/detect-config.c

@@ -0,0 +1,318 @@
+/* Copyright (C) 2007-2020 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 Victor Julien <victor@inliniac.net>
+ *
+ * Implements the config 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-state.h"
+
+#include "feature.h"
+
+#include "flow.h"
+#include "flow-var.h"
+#include "flow-util.h"
+
+#include "util-debug.h"
+#include "util-spm-bm.h"
+#include "util-unittest.h"
+#include "util-unittest-helper.h"
+
+#include "app-layer.h"
+#include "app-layer-parser.h"
+#include "app-layer-htp.h"
+
+#include "stream-tcp.h"
+
+#include "detect-config.h"
+
+#include "output.h"
+
+/**
+ * \brief Regex for parsing our flow options
+ */
+#define PARSE_REGEX  "^\\s*([A-z_]+)\\s*\\s*([A-z_]+)\\s*(?:,\\s*([A-z_]+)\\s+([A-z_]+))?\\s*(?:,\\s*([A-z_]+)\\s+([A-z_]+))?$"
+
+static DetectParseRegex parse_regex;
+
+static int DetectConfigPostMatch (DetectEngineThreadCtx *det_ctx, Packet *p,
+        const Signature *s, const SigMatchCtx *ctx);
+static int DetectConfigSetup (DetectEngineCtx *, Signature *, const char *);
+static void DetectConfigFree(DetectEngineCtx *, void *);
+static void DetectConfigRegisterTests(void);
+
+/**
+ * \brief Registration function for keyword: filestore
+ */
+void DetectConfigRegister(void)
+{
+    sigmatch_table[DETECT_CONFIG].name = "config";
+    sigmatch_table[DETECT_CONFIG].Match = DetectConfigPostMatch;
+    sigmatch_table[DETECT_CONFIG].Setup = DetectConfigSetup;
+    sigmatch_table[DETECT_CONFIG].Free  = DetectConfigFree;
+    sigmatch_table[DETECT_CONFIG].RegisterTests = DetectConfigRegisterTests;
+
+    DetectSetupParseRegexes(PARSE_REGEX, &parse_regex);
+}
+
+static void ConfigApplyTx(Flow *f,
+        const uint64_t tx_id, const DetectConfigData *config)
+{
+    void *tx = AppLayerParserGetTx(f->proto, f->alproto, f->alstate, tx_id);
+    if (tx) {
+        AppLayerTxData *txd = AppLayerParserGetTxData(f->proto, f->alproto, tx);
+        if (txd) {
+            SCLogDebug("tx %p txd %p: log_flags %x", tx, txd, txd->config.log_flags);
+            txd->config.log_flags |= BIT_U8(config->type);
+        } else {
+            SCLogDebug("no tx data");
+        }
+    } else {
+        SCLogDebug("no tx");
+    }
+}
+
+/**
+ *  \brief apply the post match filestore with options
+ */
+static int ConfigApply(DetectEngineThreadCtx *det_ctx,
+        Packet *p, const DetectConfigData *config)
+{
+    bool this_tx = false;
+    bool this_flow = false;
+
+    switch (config->scope) {
+        case CONFIG_SCOPE_TX:
+            this_tx = true;
+            break;
+        case CONFIG_SCOPE_FLOW:
+            this_flow = true;
+            break;
+    }
+
+    if (this_tx) {
+        SCLogDebug("tx logic here: tx_id %"PRIu64, det_ctx->tx_id);
+        ConfigApplyTx(p->flow, det_ctx->tx_id, config);
+    } else if (this_flow) {
+        SCLogDebug("flow logic here");
+    }
+
+    SCReturnInt(0);
+}
+
+static int DetectConfigPostMatch(DetectEngineThreadCtx *det_ctx,
+        Packet *p, const Signature *s, const SigMatchCtx *ctx)
+{
+    SCEnter();
+    const DetectConfigData *config = (const DetectConfigData *)ctx;
+    ConfigApply(det_ctx, p, config);
+    SCReturnInt(1);
+}
+
+/**
+ * \brief this function is used to parse filestore options
+ * \brief into the current signature
+ *
+ * \param de_ctx pointer to the Detection Engine Context
+ * \param s pointer to the Current Signature
+ * \param str pointer to the user provided "filestore" option
+ *
+ * \retval 0 on Success
+ * \retval -1 on Failure
+ */
+static int DetectConfigSetup (DetectEngineCtx *de_ctx, Signature *s, const char *str)
+{
+    SCEnter();
+
+    DetectConfigData *fd = NULL;
+    SigMatch *sm = NULL;
+#define MAX_SUBSTRINGS 30
+    int ret = 0, res = 0;
+    int ov[MAX_SUBSTRINGS];
+#if 0
+    /* filestore and bypass keywords can't work together */
+    if (s->flags & SIG_FLAG_BYPASS) {
+        SCLogError(SC_ERR_CONFLICTING_RULE_KEYWORDS,
+                   "filestore can't work with bypass keyword");
+        return -1;
+    }
+#endif
+    sm = SigMatchAlloc();
+    if (sm == NULL)
+        goto error;
+    sm->type = DETECT_CONFIG;
+
+    if (str == NULL || strlen(str) == 0) {
+        SCLogError(SC_ERR_INVALID_RULE_ARGUMENT, "config keywords need arguments");
+        goto error;
+    }
+    char subsys[32];
+    char state[32];
+    char type[32];
+    char typeval[32];
+    char scope[32];
+    char scopeval[32];
+    SCLogDebug("str %s", str);
+
+    ret = DetectParsePcreExec(&parse_regex,  str, 0, 0, ov, MAX_SUBSTRINGS);
+    if (ret != 7) {
+        SCLogError(SC_ERR_INVALID_RULE_ARGUMENT, "config is rather picky at this time");
+        goto error;
+    }
+    res = pcre_copy_substring((char *)str, ov, MAX_SUBSTRINGS, 1, subsys, sizeof(subsys));
+    if (res < 0) {
+        SCLogError(SC_ERR_PCRE_COPY_SUBSTRING, "pcre_copy_substring failed");
+        goto error;
+    }
+
+    if (strcmp(subsys, "logging") != 0) {
+        SCLogError(SC_ERR_INVALID_RULE_ARGUMENT, "only 'logging' supported at this time");
+        goto error;
+    }
+    SCLogDebug("subsys %s", subsys);
+
+    res = pcre_copy_substring((char *)str, ov, MAX_SUBSTRINGS, 2, state, sizeof(state));
+    if (res < 0) {
+        SCLogError(SC_ERR_PCRE_COPY_SUBSTRING, "pcre_copy_substring failed");
+        goto error;
+    }
+
+    if (strcmp(state, "disable") != 0) {
+        SCLogError(SC_ERR_INVALID_RULE_ARGUMENT, "only 'disable' supported at this time");
+        goto error;
+    }
+    SCLogDebug("state %s", state);
+
+    res = pcre_copy_substring((char *)str, ov, MAX_SUBSTRINGS, 3, type, sizeof(type));
+    if (res < 0) {
+        SCLogError(SC_ERR_PCRE_COPY_SUBSTRING, "pcre_copy_substring failed");
+        goto error;
+    }
+
+    if (strcmp(type, "type") != 0) {
+        SCLogError(SC_ERR_INVALID_RULE_ARGUMENT, "only 'type' supported at this time");
+        goto error;
+    }
+    SCLogDebug("type %s", type);
+
+    res = pcre_copy_substring((char *)str, ov, MAX_SUBSTRINGS, 4, typeval, sizeof(typeval));
+    if (res < 0) {
+        SCLogError(SC_ERR_PCRE_COPY_SUBSTRING, "pcre_copy_substring failed");
+        goto error;
+    }
+
+    if (!(strcmp(typeval, "tx") == 0 ||strcmp(typeval, "flow") == 0)) {
+        SCLogError(SC_ERR_INVALID_RULE_ARGUMENT, "only 'tx' and 'flow' supported at this time");
+        goto error;
+    }
+    SCLogDebug("typeval %s", typeval);
+
+    res = pcre_copy_substring((char *)str, ov, MAX_SUBSTRINGS, 5, scope, sizeof(scope));
+    if (res < 0) {
+        SCLogError(SC_ERR_PCRE_COPY_SUBSTRING, "pcre_copy_substring failed");
+        goto error;
+    }
+
+    if (strcmp(scope, "scope") != 0) {
+        SCLogError(SC_ERR_INVALID_RULE_ARGUMENT, "only 'scope' supported at this time");
+        goto error;
+    }
+    SCLogDebug("scope %s", scope);
+
+    res = pcre_copy_substring((char *)str, ov, MAX_SUBSTRINGS, 6, scopeval, sizeof(scopeval));
+    if (res < 0) {
+        SCLogError(SC_ERR_PCRE_COPY_SUBSTRING, "pcre_copy_substring failed");
+        goto error;
+    }
+
+    if (!(strcmp(scopeval, "tx") == 0 ||strcmp(scopeval, "flow") == 0)) {
+        SCLogError(SC_ERR_INVALID_RULE_ARGUMENT, "only 'tx' and 'flow' supported at this time");
+        goto error;
+    }
+    SCLogDebug("scopeval %s", scopeval);
+
+    fd = SCCalloc(1, sizeof(DetectConfigData));
+    if (unlikely(fd == NULL))
+        goto error;
+
+    if (strcmp(typeval, "tx") == 0) {
+        fd->type = CONFIG_TYPE_TX;
+    }
+    if (strcmp(scopeval, "tx") == 0) {
+        fd->scope = CONFIG_SCOPE_TX;
+    }
+
+    sm->ctx = (SigMatchCtx*)fd;
+    SigMatchAppendSMToList(s, sm, DETECT_SM_LIST_POSTMATCH);
+
+    return 0;
+
+error:
+    if (sm != NULL)
+        SCFree(sm);
+    return -1;
+}
+
+static void DetectConfigFree(DetectEngineCtx *de_ctx, void *ptr)
+{
+    if (ptr != NULL) {
+        SCFree(ptr);
+    }
+}
+
+#ifdef UNITTESTS
+/*
+ * The purpose of this test is to confirm that
+ * filestore and bypass keywords can't
+ * can't work together
+ */
+static int DetectConfigTest01(void)
+{
+    DetectEngineCtx *de_ctx = DetectEngineCtxInit();
+    FAIL_IF(de_ctx == NULL);
+    de_ctx->flags |= DE_QUIET;
+    Signature *s = DetectEngineAppendSig(de_ctx,
+            "config dns any any -> any any ("
+            "dns.query; content:\"common.domain.com\"; "
+            "config:logging disable, type tx, scope tx; "
+            "sid:1;)");
+    FAIL_IF_NULL(s);
+    DetectEngineCtxFree(de_ctx);
+    PASS;
+}
+#endif /* UNITTESTS */
+
+void DetectConfigRegisterTests(void)
+{
+#ifdef UNITTESTS
+    UtRegisterTest("DetectConfigTest01", DetectConfigTest01);
+#endif /* UNITTESTS */
+}

src/detect-config.h

@@ -0,0 +1,38 @@
+/* Copyright (C) 2007-2020 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 Victor Julien <victor@inliniac.net>
+ */
+
+#ifndef __DETECT_CONFIG_H__
+#define __DETECT_CONFIG_H__
+
+#include "util-config.h"
+
+typedef struct DetectConfigData_ {
+    enum ConfigSubsys subsys;
+    enum ConfigType type;
+    enum ConfigScope scope;
+} DetectConfigData;
+
+/* prototypes */
+void DetectConfigRegister (void);
+
+#endif /* __DETECT_CONFIG_H__ */

src/detect-engine-register.c

@@ -71,6 +71,8 @@
 #include "detect-engine-event.h"
 #include "decode.h"
 
+#include "detect-config.h"
+
 #include "detect-smb-share.h"
 
 #include "detect-base64-decode.h"
@@ -586,6 +588,7 @@ void SigTableSetup(void)
     DetectSNMPPduTypeRegister();
     DetectTemplateBufferRegister();
     DetectBypassRegister();
+    DetectConfigRegister();
 
     DetectTransformCompressWhitespaceRegister();
     DetectTransformStripWhitespaceRegister();

src/detect-engine-register.h

@@ -183,6 +183,8 @@ enum DetectKeywordId {
     DETECT_ENGINE_EVENT,
     DETECT_STREAM_EVENT,
 
+    DETECT_CONFIG,
+
     DETECT_FILENAME,
     DETECT_FILE_NAME,
     DETECT_FILEEXT,