Adding upstream version 1:7.0.3.upstream/1%7.0.3

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 409 insertions, 0 deletions

diff --git a/src/detect-filemagic.c b/src/detect-filemagic.c
new file mode 100644
index 0000000..b1c5359
--- /dev/null
+++ b/src/detect-filemagic.c
@@ -0,0 +1,409 @@
+/* Copyright (C) 2007-2023 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>
+ *
+ */
+
+#include "suricata-common.h"
+#include "threads.h"
+#include "decode.h"
+
+#include "detect.h"
+#include "detect-parse.h"
+#include "detect-content.h"
+
+#include "detect-engine.h"
+#include "detect-engine-mpm.h"
+#include "detect-engine-prefilter.h"
+#include "detect-engine-content-inspection.h"
+#include "detect-engine-file.h"
+
+#include "flow.h"
+#include "flow-var.h"
+#include "flow-util.h"
+
+#include "util-debug.h"
+#include "util-spm-bm.h"
+#include "util-magic.h"
+#include "util-print.h"
+
+#include "util-unittest.h"
+#include "util-unittest-helper.h"
+#include "util-profiling.h"
+
+#include "app-layer.h"
+#include "app-layer-parser.h"
+
+#include "stream-tcp.h"
+
+#include "detect-file-data.h"
+#include "detect-filemagic.h"
+
+#include "conf.h"
+
+#ifndef HAVE_MAGIC
+
+static int DetectFilemagicSetupNoSupport (DetectEngineCtx *de_ctx, Signature *s, const char *str)
+{
+    SCLogError("no libmagic support built in, needed for filemagic keyword");
+    return -1;
+}
+
+/**
+ * \brief Registration function for keyword: filemagic
+ */
+void DetectFilemagicRegister(void)
+{
+    sigmatch_table[DETECT_FILEMAGIC].name = "filemagic";
+    sigmatch_table[DETECT_FILEMAGIC].desc = "match on the information libmagic returns about a file";
+    sigmatch_table[DETECT_FILEMAGIC].url = "/rules/file-keywords.html#filemagic";
+    sigmatch_table[DETECT_FILEMAGIC].Setup = DetectFilemagicSetupNoSupport;
+    sigmatch_table[DETECT_FILEMAGIC].flags = SIGMATCH_QUOTES_MANDATORY|SIGMATCH_HANDLE_NEGATION;
+}
+
+#else /* HAVE_MAGIC */
+
+typedef struct DetectFilemagicThreadData {
+    magic_t ctx;
+} DetectFilemagicThreadData;
+
+static int DetectFilemagicSetup(DetectEngineCtx *, Signature *, const char *);
+static int g_file_match_list_id = 0;
+
+static int DetectFilemagicSetupSticky(DetectEngineCtx *de_ctx, Signature *s, const char *str);
+static int g_file_magic_buffer_id = 0;
+
+static int PrefilterMpmFilemagicRegister(DetectEngineCtx *de_ctx, SigGroupHead *sgh,
+        MpmCtx *mpm_ctx, const DetectBufferMpmRegistry *mpm_reg, int list_id);
+static uint8_t DetectEngineInspectFilemagic(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);
+
+/**
+ * \brief Registration function for keyword: filemagic
+ */
+void DetectFilemagicRegister(void)
+{
+    sigmatch_table[DETECT_FILEMAGIC].name = "filemagic";
+    sigmatch_table[DETECT_FILEMAGIC].desc = "match on the information libmagic returns about a file";
+    sigmatch_table[DETECT_FILEMAGIC].url = "/rules/file-keywords.html#filemagic";
+    sigmatch_table[DETECT_FILEMAGIC].Setup = DetectFilemagicSetup;
+    sigmatch_table[DETECT_FILEMAGIC].flags = SIGMATCH_QUOTES_MANDATORY|SIGMATCH_HANDLE_NEGATION;
+    sigmatch_table[DETECT_FILEMAGIC].alternative = DETECT_FILE_MAGIC;
+
+    sigmatch_table[DETECT_FILE_MAGIC].name = "file.magic";
+    sigmatch_table[DETECT_FILE_MAGIC].desc = "sticky buffer to match on the file magic";
+    sigmatch_table[DETECT_FILE_MAGIC].url = "/rules/file-keywords.html#filemagic";
+    sigmatch_table[DETECT_FILE_MAGIC].Setup = DetectFilemagicSetupSticky;
+    sigmatch_table[DETECT_FILE_MAGIC].flags = SIGMATCH_NOOPT|SIGMATCH_INFO_STICKY_BUFFER;
+
+    filehandler_table[DETECT_FILE_MAGIC].name = "file.magic",
+    filehandler_table[DETECT_FILE_MAGIC].priority = 2;
+    filehandler_table[DETECT_FILE_MAGIC].PrefilterFn = PrefilterMpmFilemagicRegister;
+    filehandler_table[DETECT_FILE_MAGIC].Callback = DetectEngineInspectFilemagic;
+
+    g_file_match_list_id = DetectBufferTypeRegister("files");
+
+    DetectBufferTypeSetDescriptionByName("file.magic", "file magic");
+    DetectBufferTypeSupportsMultiInstance("file.magic");
+
+    g_file_magic_buffer_id = DetectBufferTypeGetByName("file.magic");
+	SCLogDebug("registering filemagic rule option");
+    return;
+}
+
+#define FILEMAGIC_MIN_SIZE  512
+
+/**
+ *  \brief run the magic check
+ *
+ *  \param file the file
+ *
+ *  \retval -1 error
+ *  \retval 0 ok
+ */
+int FilemagicThreadLookup(magic_t *ctx, File *file)
+{
+    if (ctx == NULL || file == NULL || FileDataSize(file) == 0) {
+        SCReturnInt(-1);
+    }
+
+    const uint8_t *data = NULL;
+    uint32_t data_len = 0;
+    uint64_t offset = 0;
+
+    StreamingBufferGetData(file->sb,
+                           &data, &data_len, &offset);
+    if (offset == 0) {
+        if (FileDataSize(file) >= FILEMAGIC_MIN_SIZE) {
+            file->magic = MagicThreadLookup(ctx, data, data_len);
+        } else if (file->state >= FILE_STATE_CLOSED) {
+            file->magic = MagicThreadLookup(ctx, data, data_len);
+        }
+    }
+    SCReturnInt(0);
+}
+
+static void *DetectFilemagicThreadInit(void *data /*@unused@*/)
+{
+    DetectFilemagicThreadData *t = SCCalloc(1, sizeof(DetectFilemagicThreadData));
+    if (unlikely(t == NULL)) {
+        SCLogError("couldn't alloc ctx memory");
+        return NULL;
+    }
+
+    t->ctx = MagicInitContext();
+    if (t->ctx == NULL)
+        goto error;
+
+    return (void *)t;
+
+error:
+    if (t->ctx)
+        magic_close(t->ctx);
+    SCFree(t);
+    return NULL;
+}
+
+static void DetectFilemagicThreadFree(void *ctx)
+{
+    if (ctx != NULL) {
+        DetectFilemagicThreadData *t = (DetectFilemagicThreadData *)ctx;
+        if (t->ctx)
+            magic_close(t->ctx);
+        SCFree(t);
+    }
+}
+
+/**
+ * \brief this function is used to parse filemagic 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 "filemagic" option
+ *
+ * \retval 0 on Success
+ * \retval -1 on Failure
+ */
+static int DetectFilemagicSetup (DetectEngineCtx *de_ctx, Signature *s, const char *str)
+{
+    if (s->init_data->transforms.cnt) {
+        SCLogError("previous transforms not consumed before 'filemagic'");
+        SCReturnInt(-1);
+    }
+    s->init_data->list = DETECT_SM_LIST_NOTSET;
+    s->file_flags |= (FILE_SIG_NEED_FILE | FILE_SIG_NEED_MAGIC);
+
+    if (DetectContentSetup(de_ctx, s, str) < 0) {
+        return -1;
+    }
+
+    SigMatch *sm = DetectGetLastSMFromLists(s, DETECT_CONTENT, -1);
+    if (sm == NULL)
+        return -1;
+
+    DetectContentData *cd = (DetectContentData *)sm->ctx;
+    if (DetectContentConvertToNocase(de_ctx, cd) != 0)
+        return -1;
+    if (DetectEngineContentModifierBufferSetup(
+                de_ctx, s, NULL, DETECT_FILE_MAGIC, g_file_magic_buffer_id, s->alproto) < 0)
+        return -1;
+
+    if (de_ctx->filemagic_thread_ctx_id == -1) {
+        de_ctx->filemagic_thread_ctx_id = DetectRegisterThreadCtxFuncs(
+                de_ctx, "filemagic", DetectFilemagicThreadInit, NULL, DetectFilemagicThreadFree, 1);
+        if (de_ctx->filemagic_thread_ctx_id == -1)
+            return -1;
+    }
+    return 0;
+}
+
+/* file.magic implementation */
+
+/**
+ * \brief this function setup the file.magic 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
+ */
+static int DetectFilemagicSetupSticky(DetectEngineCtx *de_ctx, Signature *s, const char *str)
+{
+    if (DetectBufferSetActiveList(de_ctx, s, g_file_magic_buffer_id) < 0)
+        return -1;
+
+    if (de_ctx->filemagic_thread_ctx_id == -1) {
+        de_ctx->filemagic_thread_ctx_id = DetectRegisterThreadCtxFuncs(
+                de_ctx, "filemagic", DetectFilemagicThreadInit, NULL, DetectFilemagicThreadFree, 1);
+        if (de_ctx->filemagic_thread_ctx_id == -1)
+            return -1;
+    }
+    return 0;
+}
+
+static InspectionBuffer *FilemagicGetDataCallback(DetectEngineThreadCtx *det_ctx,
+        const DetectEngineTransforms *transforms, Flow *f, uint8_t flow_flags, File *cur_file,
+        int list_id, int local_file_id)
+{
+    SCEnter();
+
+    InspectionBuffer *buffer = InspectionBufferMultipleForListGet(det_ctx, list_id, local_file_id);
+    if (buffer == NULL)
+        return NULL;
+    if (buffer->initialized)
+        return buffer;
+
+    if (cur_file->magic == NULL) {
+        DetectFilemagicThreadData *tfilemagic =
+                (DetectFilemagicThreadData *)DetectThreadCtxGetKeywordThreadCtx(
+                        det_ctx, det_ctx->de_ctx->filemagic_thread_ctx_id);
+        if (tfilemagic == NULL) {
+            InspectionBufferSetupMultiEmpty(buffer);
+            return NULL;
+        }
+
+        FilemagicThreadLookup(&tfilemagic->ctx, cur_file);
+    }
+    if (cur_file->magic == NULL) {
+        return NULL;
+    }
+
+    const uint8_t *data = (const uint8_t *)cur_file->magic;
+    uint32_t data_len = (uint32_t)strlen(cur_file->magic);
+
+    InspectionBufferSetupMulti(buffer, transforms, data, data_len);
+
+    SCReturnPtr(buffer, "InspectionBuffer");
+}
+
+static uint8_t DetectEngineInspectFilemagic(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)
+{
+    const DetectEngineTransforms *transforms = NULL;
+    if (!engine->mpm) {
+        transforms = engine->v2.transforms;
+    }
+
+    AppLayerGetFileState files = AppLayerParserGetTxFiles(f, alstate, txv, flags);
+    FileContainer *ffc = files.fc;
+    if (ffc == NULL) {
+        return DETECT_ENGINE_INSPECT_SIG_CANT_MATCH_FILES;
+    }
+
+    uint8_t r = DETECT_ENGINE_INSPECT_SIG_NO_MATCH;
+    int local_file_id = 0;
+    for (File *file = ffc->head; file != NULL; file = file->next) {
+        InspectionBuffer *buffer = FilemagicGetDataCallback(
+                det_ctx, transforms, f, flags, file, engine->sm_list, local_file_id);
+        if (buffer == NULL)
+            continue;
+
+        det_ctx->buffer_offset = 0;
+        det_ctx->discontinue_matching = 0;
+        det_ctx->inspection_recursion_counter = 0;
+        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;
+        } else {
+            r = DETECT_ENGINE_INSPECT_SIG_CANT_MATCH_FILES;
+        }
+        local_file_id++;
+    }
+    return r;
+}
+
+typedef struct PrefilterMpmFilemagic {
+    int list_id;
+    const MpmCtx *mpm_ctx;
+    const DetectEngineTransforms *transforms;
+} PrefilterMpmFilemagic;
+
+/** \brief Filedata Filedata 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 PrefilterTxFilemagic(DetectEngineThreadCtx *det_ctx, const void *pectx, Packet *p,
+        Flow *f, void *txv, const uint64_t idx, const AppLayerTxData *txd, const uint8_t flags)
+{
+    SCEnter();
+
+    if (!AppLayerParserHasFilesInDir(txd, flags))
+        return;
+
+    const PrefilterMpmFilemagic *ctx = (const PrefilterMpmFilemagic *)pectx;
+    const MpmCtx *mpm_ctx = ctx->mpm_ctx;
+    const int list_id = ctx->list_id;
+
+    AppLayerGetFileState files = AppLayerParserGetTxFiles(f, f->alstate, txv, flags);
+    FileContainer *ffc = files.fc;
+    if (ffc != NULL) {
+        int local_file_id = 0;
+        for (File *file = ffc->head; file != NULL; file = file->next) {
+            InspectionBuffer *buffer = FilemagicGetDataCallback(
+                    det_ctx, ctx->transforms, f, flags, file, list_id, local_file_id);
+            if (buffer == NULL)
+                continue;
+
+            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);
+                PREFILTER_PROFILING_ADD_BYTES(det_ctx, buffer->inspect_len);
+            }
+            local_file_id++;
+        }
+    }
+}
+
+static void PrefilterMpmFilemagicFree(void *ptr)
+{
+    SCFree(ptr);
+}
+
+static int PrefilterMpmFilemagicRegister(DetectEngineCtx *de_ctx, SigGroupHead *sgh,
+        MpmCtx *mpm_ctx, const DetectBufferMpmRegistry *mpm_reg, int list_id)
+{
+    PrefilterMpmFilemagic *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, PrefilterTxFilemagic,
+            mpm_reg->app_v2.alproto, mpm_reg->app_v2.tx_min_progress,
+            pectx, PrefilterMpmFilemagicFree, mpm_reg->pname);
+}
+
+#endif /* HAVE_MAGIC */