detect/fileext: reimplement based on file.name

Ticket: #6194.
(cherry picked from commit 9b09b29350f846e917dab5a3a8351ef7988362b1)

diff --git a/src/Makefile.am b/src/Makefile.am
index 650a0945e932edee736fe0de699735f5e3ee1d6a..ff962da84a07605a2b0d6c8cd1162a378e80e6f2 100755 (executable)
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -166,7 +166,6 @@ detect-engine-uint.c detect-engine-uint.h \
 detect-fast-pattern.c detect-fast-pattern.h \
 detect-file-data.c detect-file-data.h \
 detect-file-hash-common.c detect-file-hash-common.h \
-detect-fileext.c detect-fileext.h \
 detect-filemagic.c detect-filemagic.h \
 detect-filemd5.c detect-filemd5.h \
 detect-filesha1.c detect-filesha1.h \

diff --git a/src/detect-engine-register.c b/src/detect-engine-register.c
index 3f849125a5a0258ffca52517baa415c47d4cf99f..e131fe3e8bba52e60650371bf53cf19e5ee73e2a 100644 (file)
--- a/src/detect-engine-register.c
+++ b/src/detect-engine-register.c
@@ -117,7 +117,6 @@
 #include "detect-rpc.h"
 #include "detect-asn1.h"
 #include "detect-filename.h"
-#include "detect-fileext.h"
 #include "detect-filestore.h"
 #include "detect-filemagic.h"
 #include "detect-filemd5.h"
@@ -462,7 +461,6 @@ void SigTableSetup(void)
     DetectHttpCookieRegister();
 
     DetectFilenameRegister();
-    DetectFileextRegister();
     DetectFilestoreRegister();
     DetectFilemagicRegister();
     DetectFileMd5Register();

diff --git a/src/detect-fileext.c b/src/detect-fileext.c
deleted file mode 100644 (file)
index 35805d6..0000000
--- a/src/detect-fileext.c
+++ /dev/null
@@ -1,310 +0,0 @@
-/* Copyright (C) 2007-2012 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>
- * \author Pablo Rincon <pablo.rincon.crespo@gmail.com>
- *
- */
-
-#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 "flow.h"
-#include "flow-var.h"
-#include "flow-util.h"
-
-#include "util-debug.h"
-#include "util-unittest.h"
-#include "util-unittest-helper.h"
-#include "util-spm-bm.h"
-#include "util-print.h"
-#include "util-memcmp.h"
-
-#include "app-layer.h"
-
-#include "stream-tcp.h"
-#include "detect-fileext.h"
-
-static int DetectFileextMatch (DetectEngineThreadCtx *, Flow *,
-        uint8_t, File *, const Signature *, const SigMatchCtx *);
-static int DetectFileextSetup (DetectEngineCtx *, Signature *, const char *);
-#ifdef UNITTESTS
-static void DetectFileextRegisterTests(void);
-#endif
-static void DetectFileextFree(DetectEngineCtx *, void *);
-static int g_file_match_list_id = 0;
-
-/**
- * \brief Registration function for keyword: fileext
- */
-void DetectFileextRegister(void)
-{
-    sigmatch_table[DETECT_FILEEXT].name = "fileext";
-    sigmatch_table[DETECT_FILEEXT].desc = "match on the extension of a file name";
-    sigmatch_table[DETECT_FILEEXT].url = "/rules/file-keywords.html#fileext";
-    sigmatch_table[DETECT_FILEEXT].FileMatch = DetectFileextMatch;
-    sigmatch_table[DETECT_FILEEXT].Setup = DetectFileextSetup;
-    sigmatch_table[DETECT_FILEEXT].Free  = DetectFileextFree;
-#ifdef UNITTESTS
-    sigmatch_table[DETECT_FILEEXT].RegisterTests = DetectFileextRegisterTests;
-#endif
-    sigmatch_table[DETECT_FILEEXT].flags = SIGMATCH_QUOTES_OPTIONAL|SIGMATCH_HANDLE_NEGATION;
-    sigmatch_table[DETECT_FILEEXT].alternative = DETECT_FILE_NAME;
-
-    g_file_match_list_id = DetectBufferTypeRegister("files");
-
-       SCLogDebug("registering fileext rule option");
-    return;
-}
-
-/**
- * \brief match the specified file extension
- *
- * \param t thread local vars
- * \param det_ctx pattern matcher thread local data
- * \param f *LOCKED* flow
- * \param flags direction flags
- * \param file file being inspected
- * \param s signature being inspected
- * \param m sigmatch that we will cast into DetectFileextData
- *
- * \retval 0 no match
- * \retval 1 match
- */
-static int DetectFileextMatch (DetectEngineThreadCtx *det_ctx,
-        Flow *f, uint8_t flags, File *file, const Signature *s, const SigMatchCtx *m)
-{
-    SCEnter();
-    int ret = 0;
-
-    DetectFileextData *fileext = (DetectFileextData *)m;
-
-    if (file->name == NULL)
-        SCReturnInt(0);
-
-    if (file->name_len <= fileext->len)
-        SCReturnInt(0);
-
-    int offset = file->name_len - fileext->len;
-
-    /* fileext->ext is already in lowercase, as SCMemcmpLowercase requires */
-    if (file->name[offset - 1] == '.' &&
-        SCMemcmpLowercase(fileext->ext, file->name + offset, fileext->len) == 0)
-    {
-        if (!(fileext->flags & DETECT_CONTENT_NEGATED)) {
-            ret = 1;
-            SCLogDebug("File ext found");
-        }
-    } else if (fileext->flags & DETECT_CONTENT_NEGATED) {
-        SCLogDebug("negated match");
-        ret = 1;
-    }
-
-    SCReturnInt(ret);
-}
-
-/**
- * \brief This function is used to parse fileet
- *
- * \param de_ctx Pointer to the detection engine context
- * \param str Pointer to the fileext value string
- *
- * \retval pointer to DetectFileextData on success
- * \retval NULL on failure
- */
-static DetectFileextData *DetectFileextParse(
-        DetectEngineCtx *de_ctx, const char *str, bool negate, bool *warning)
-{
-    DetectFileextData *fileext = NULL;
-
-    /* We have a correct filename option */
-    fileext = SCMalloc(sizeof(DetectFileextData));
-    if (unlikely(fileext == NULL))
-        goto error;
-
-    memset(fileext, 0x00, sizeof(DetectFileextData));
-
-    if (DetectContentDataParse("fileext", str, &fileext->ext, &fileext->len, warning) == -1) {
-        goto error;
-    }
-    uint16_t u;
-    for (u = 0; u < fileext->len; u++)
-        fileext->ext[u] = tolower(fileext->ext[u]);
-
-    if (negate) {
-        fileext->flags |= DETECT_CONTENT_NEGATED;
-    }
-
-    SCLogDebug("flags %02X", fileext->flags);
-    if (fileext->flags & DETECT_CONTENT_NEGATED) {
-        SCLogDebug("negated fileext");
-    }
-
-#ifdef DEBUG
-    if (SCLogDebugEnabled()) {
-        char *ext = SCMalloc(fileext->len + 1);
-        if (ext != NULL) {
-            memcpy(ext, fileext->ext, fileext->len);
-            ext[fileext->len] = '\0';
-            SCLogDebug("will look for fileext %s", ext);
-            SCFree(ext);
-        }
-    }
-#endif
-
-    return fileext;
-
-error:
-    if (fileext != NULL)
-        DetectFileextFree(de_ctx, fileext);
-    return NULL;
-
-}
-
-/**
- * \brief this function is used to add the parsed "id" option
- *        into the current signature
- *
- * \param de_ctx pointer to the Detection Engine Context
- * \param s pointer to the Current Signature
- * \param idstr pointer to the user provided "id" option
- *
- * \retval 0 on Success
- * \retval -1 on Failure
- */
-static int DetectFileextSetup (DetectEngineCtx *de_ctx, Signature *s, const char *str)
-{
-    DetectFileextData *fileext= NULL;
-    SigMatch *sm = NULL;
-    bool warning = false;
-
-    fileext = DetectFileextParse(de_ctx, str, s->init_data->negated, &warning);
-    if (fileext == NULL)
-        goto error;
-
-    /* Okay so far so good, lets get this into a SigMatch
-     * and put it in the Signature. */
-    sm = SigMatchAlloc();
-    if (sm == NULL)
-        goto error;
-
-    sm->type = DETECT_FILEEXT;
-    sm->ctx = (void *)fileext;
-
-    SigMatchAppendSMToList(s, sm, g_file_match_list_id);
-
-    s->file_flags |= (FILE_SIG_NEED_FILE|FILE_SIG_NEED_FILENAME);
-    return 0;
-
-error:
-    if (fileext != NULL)
-        DetectFileextFree(de_ctx, fileext);
-    if (sm != NULL)
-        SCFree(sm);
-    return warning ? -4 : -1;
-}
-
-/**
- * \brief this function will free memory associated with DetectFileextData
- *
- * \param fileext pointer to DetectFileextData
- */
-static void DetectFileextFree(DetectEngineCtx *de_ctx, void *ptr)
-{
-    if (ptr != NULL) {
-        DetectFileextData *fileext = (DetectFileextData *)ptr;
-        if (fileext->ext != NULL)
-            SCFree(fileext->ext);
-        SCFree(fileext);
-    }
-}
-
-#ifdef UNITTESTS /* UNITTESTS */
-
-/**
- * \test DetectFileextTestParse01
- */
-static int DetectFileextTestParse01 (void)
-{
-    DetectFileextData *dfd = DetectFileextParse(NULL, "doc", false, NULL);
-    if (dfd != NULL) {
-        DetectFileextFree(NULL, dfd);
-        return 1;
-    }
-    return 0;
-}
-
-/**
- * \test DetectFileextTestParse02
- */
-static int DetectFileextTestParse02 (void)
-{
-    int result = 0;
-
-    DetectFileextData *dfd = DetectFileextParse(NULL, "tar.gz", false, NULL);
-    if (dfd != NULL) {
-        if (dfd->len == 6 && memcmp(dfd->ext, "tar.gz", 6) == 0) {
-            result = 1;
-        }
-
-        DetectFileextFree(NULL, dfd);
-        return result;
-    }
-    return 0;
-}
-
-/**
- * \test DetectFileextTestParse03
- */
-static int DetectFileextTestParse03 (void)
-{
-    int result = 0;
-
-    DetectFileextData *dfd = DetectFileextParse(NULL, "pdf", false, NULL);
-    if (dfd != NULL) {
-        if (dfd->len == 3 && memcmp(dfd->ext, "pdf", 3) == 0) {
-            result = 1;
-        }
-
-        DetectFileextFree(NULL, dfd);
-        return result;
-    }
-    return 0;
-}
-
-/**
- * \brief this function registers unit tests for DetectFileext
- */
-void DetectFileextRegisterTests(void)
-{
-    UtRegisterTest("DetectFileextTestParse01", DetectFileextTestParse01);
-    UtRegisterTest("DetectFileextTestParse02", DetectFileextTestParse02);
-    UtRegisterTest("DetectFileextTestParse03", DetectFileextTestParse03);
-}
-#endif /* UNITTESTS */

diff --git a/src/detect-fileext.h b/src/detect-fileext.h
deleted file mode 100644 (file)
index 4981763..0000000
--- a/src/detect-fileext.h
+++ /dev/null
@@ -1,38 +0,0 @@
-/* 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 Pablo Rincon <pablo.rincon.crespo@gmail.com>
- */
-
-#ifndef __DETECT_FILEEXT_H__
-#define __DETECT_FILEEXT_H__
-
-#include "util-spm-bm.h"
-
-typedef struct DetectFileextData_ {
-    uint8_t *ext;  /** file extension to match */
-    uint16_t len;  /** length of the file */
-    uint32_t flags;
-} DetectFileextData;
-
-/* prototypes */
-void DetectFileextRegister (void);
-
-#endif /* __DETECT_FILEEXT_H__ */

diff --git a/src/detect-filename.c b/src/detect-filename.c
index 4945d021523fccedf4aad842315a180a272d8430..2df4fd478a53195c435063f9f91ad46979af7541 100644 (file)
--- a/src/detect-filename.c
+++ b/src/detect-filename.c
@@ -54,6 +54,7 @@
 #include "detect-filename.h"
 #include "app-layer-parser.h"
 
+static int DetectFileextSetup(DetectEngineCtx *de_ctx, Signature *s, const char *str);
 static int DetectFilenameSetup (DetectEngineCtx *, Signature *, const char *);
 static int DetectFilenameSetupSticky(DetectEngineCtx *de_ctx, Signature *s, const char *str);
 #ifdef UNITTESTS
@@ -86,6 +87,13 @@ void DetectFilenameRegister(void)
     sigmatch_table[DETECT_FILENAME].flags = SIGMATCH_QUOTES_OPTIONAL|SIGMATCH_HANDLE_NEGATION;
     sigmatch_table[DETECT_FILENAME].alternative = DETECT_FILE_NAME;
 
+    sigmatch_table[DETECT_FILEEXT].name = "fileext";
+    sigmatch_table[DETECT_FILEEXT].desc = "match on the extension of a file name";
+    sigmatch_table[DETECT_FILEEXT].url = "/rules/file-keywords.html#fileext";
+    sigmatch_table[DETECT_FILEEXT].Setup = DetectFileextSetup;
+    sigmatch_table[DETECT_FILEEXT].flags = SIGMATCH_QUOTES_OPTIONAL | SIGMATCH_HANDLE_NEGATION;
+    sigmatch_table[DETECT_FILEEXT].alternative = DETECT_FILE_NAME;
+
     sigmatch_table[DETECT_FILE_NAME].name = "file.name";
     sigmatch_table[DETECT_FILE_NAME].desc = "sticky buffer to match on the file name";
     sigmatch_table[DETECT_FILE_NAME].url = "/rules/file-keywords.html#filename";
@@ -166,6 +174,47 @@ void DetectFilenameRegister(void)
     return;
 }
 
+static int DetectFileextSetup(DetectEngineCtx *de_ctx, Signature *s, const char *str)
+{
+    if (s->init_data->transforms.cnt) {
+        SCLogError(SC_ERR_INVALID_SIGNATURE, "previous transforms not consumed before 'fileext'");
+        SCReturnInt(-1);
+    }
+    s->init_data->list = DETECT_SM_LIST_NOTSET;
+    s->file_flags |= (FILE_SIG_NEED_FILE | FILE_SIG_NEED_FILENAME);
+
+    size_t dotstr_len = strlen(str) + 2;
+    char *dotstr = SCCalloc(1, dotstr_len);
+    if (dotstr == NULL)
+        return -1;
+    dotstr[0] = '.';
+    strlcat(dotstr, str, dotstr_len);
+
+    if (DetectContentSetup(de_ctx, s, dotstr) < 0) {
+        SCFree(dotstr);
+        return -1;
+    }
+    SCFree(dotstr);
+
+    SigMatch *sm = DetectGetLastSMFromLists(s, DETECT_CONTENT, -1);
+    if (sm == NULL)
+        return -1;
+
+    DetectContentData *cd = (DetectContentData *)sm->ctx;
+    cd->flags |= DETECT_CONTENT_NOCASE;
+    cd->flags |= DETECT_CONTENT_ENDS_WITH;
+    /* Recreate the context with nocase chars */
+    SpmDestroyCtx(cd->spm_ctx);
+    cd->spm_ctx = SpmInitCtx(cd->content, cd->content_len, 1, de_ctx->spm_global_thread_ctx);
+    if (cd->spm_ctx == NULL) {
+        return -1;
+    }
+    if (DetectEngineContentModifierBufferSetup(
+                de_ctx, s, NULL, DETECT_FILE_NAME, g_file_name_buffer_id, s->alproto) < 0)
+        return -1;
+
+    return 0;
+}
 /**
  * \brief this function is used to parse filename options
  * \brief into the current signature