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, 380 insertions, 0 deletions

diff --git a/src/detect-datarep.c b/src/detect-datarep.c
new file mode 100644
index 0000000..c9cc179
--- /dev/null
+++ b/src/detect-datarep.c
@@ -0,0 +1,380 @@
+/* Copyright (C) 2018-2020 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 datarep keyword
+ */
+
+#include "suricata-common.h"
+#include "decode.h"
+#include "detect.h"
+#include "threads.h"
+#include "datasets.h"
+#include "detect-datarep.h"
+
+#include "detect-parse.h"
+#include "detect-engine.h"
+#include "detect-engine-mpm.h"
+#include "detect-engine-state.h"
+
+#include "util-byte.h"
+#include "util-debug.h"
+#include "util-print.h"
+#include "util-misc.h"
+#include "util-path.h"
+
+#define PARSE_REGEX         "([a-z]+)(?:,\\s*([\\-_A-z0-9\\s\\.]+)){1,4}"
+static DetectParseRegex parse_regex;
+
+int DetectDatarepMatch (ThreadVars *, DetectEngineThreadCtx *, Packet *,
+        const Signature *, const SigMatchCtx *);
+static int DetectDatarepSetup (DetectEngineCtx *, Signature *, const char *);
+void DetectDatarepFree (DetectEngineCtx *, void *);
+
+void DetectDatarepRegister (void)
+{
+    sigmatch_table[DETECT_DATAREP].name = "datarep";
+    sigmatch_table[DETECT_DATAREP].desc = "operate on datasets (experimental)";
+    sigmatch_table[DETECT_DATAREP].url = "/rules/dataset-keywords.html#datarep";
+    sigmatch_table[DETECT_DATAREP].Setup = DetectDatarepSetup;
+    sigmatch_table[DETECT_DATAREP].Free  = DetectDatarepFree;
+
+    DetectSetupParseRegexes(PARSE_REGEX, &parse_regex);
+}
+
+/*
+    1 match
+    0 no match
+    -1 can't match
+ */
+int DetectDatarepBufferMatch(DetectEngineThreadCtx *det_ctx,
+    const DetectDatarepData *sd,
+    const uint8_t *data, const uint32_t data_len)
+{
+    if (data == NULL || data_len == 0)
+        return 0;
+
+    DataRepResultType r = DatasetLookupwRep(sd->set, data, data_len, &sd->rep);
+    if (!r.found)
+        return 0;
+
+    switch (sd->op) {
+        case DATAREP_OP_GT:
+            if (r.rep.value > sd->rep.value)
+                return 1;
+            break;
+        case DATAREP_OP_LT:
+            if (r.rep.value < sd->rep.value)
+                return 1;
+            break;
+        case DATAREP_OP_EQ:
+            if (r.rep.value == sd->rep.value)
+                return 1;
+            break;
+    }
+    return 0;
+}
+
+static int DetectDatarepParse(const char *str, char *cmd, int cmd_len, char *name, int name_len,
+        enum DatasetTypes *type, char *load, size_t load_size, uint16_t *rep_value,
+        uint64_t *memcap, uint32_t *hashsize)
+{
+    bool cmd_set = false;
+    bool name_set = false;
+    bool value_set = false;
+
+    char copy[strlen(str)+1];
+    strlcpy(copy, str, sizeof(copy));
+    char *xsaveptr = NULL;
+    char *key = strtok_r(copy, ",", &xsaveptr);
+    while (key != NULL) {
+        while (*key != '\0' && isblank(*key)) {
+            key++;
+        }
+        char *val = strchr(key, ' ');
+        if (val != NULL) {
+            *val++ = '\0';
+            while (*val != '\0' && isblank(*val)) {
+                val++;
+                SCLogDebug("cmd %s val %s", key, val);
+            }
+        } else {
+            SCLogDebug("cmd %s", key);
+        }
+
+        if (strlen(key) == 0) {
+            goto next;
+        }
+
+        if (!name_set) {
+            if (val) {
+                return -1;
+            }
+            strlcpy(name, key, name_len);
+            name_set = true;
+        } else if (!cmd_set) {
+            if (val) {
+                return -1;
+            }
+            strlcpy(cmd, key, cmd_len);
+            cmd_set = true;
+        } else if (!value_set) {
+            if (val) {
+                return -1;
+            }
+
+            if (StringParseUint16(rep_value, 10, 0, key) < 0)
+                return -1;
+
+            value_set = true;
+        } else {
+            if (val == NULL) {
+                return -1;
+            }
+
+            if (strcmp(key, "type") == 0) {
+                SCLogDebug("type %s", val);
+
+                if (strcmp(val, "md5") == 0) {
+                    *type = DATASET_TYPE_MD5;
+                } else if (strcmp(val, "sha256") == 0) {
+                    *type = DATASET_TYPE_SHA256;
+                } else if (strcmp(val, "string") == 0) {
+                    *type = DATASET_TYPE_STRING;
+                } else if (strcmp(val, "ipv4") == 0) {
+                    *type = DATASET_TYPE_IPV4;
+                } else if (strcmp(val, "ip") == 0) {
+                    *type = DATASET_TYPE_IPV6;
+                } else if (strcmp(val, "ipv6") == 0) {
+                    *type = DATASET_TYPE_IPV6;
+                } else {
+                    SCLogDebug("bad type %s", val);
+                    return -1;
+                }
+
+            } else if (strcmp(key, "load") == 0) {
+                SCLogDebug("load %s", val);
+                strlcpy(load, val, load_size);
+            }
+            if (strcmp(key, "memcap") == 0) {
+                if (ParseSizeStringU64(val, memcap) < 0) {
+                    SCLogWarning("invalid value for memcap: %s,"
+                                 " resetting to default",
+                            val);
+                    *memcap = 0;
+                }
+            }
+            if (strcmp(key, "hashsize") == 0) {
+                if (ParseSizeStringU32(val, hashsize) < 0) {
+                    SCLogWarning("invalid value for hashsize: %s,"
+                                 " resetting to default",
+                            val);
+                    *hashsize = 0;
+                }
+            }
+        }
+
+        SCLogDebug("key: %s, value: %s", key, val);
+
+    next:
+        key = strtok_r(NULL, ",", &xsaveptr);
+    }
+
+    if (strlen(load) > 0 && *type == DATASET_TYPE_NOTSET) {
+        SCLogError("if load is used type must be set as well");
+        return 0;
+    }
+
+    if (!name_set || !cmd_set || !value_set) {
+        SCLogError("missing values");
+        return 0;
+    }
+
+    /* Trim trailing whitespace. */
+    while (strlen(name) > 0 && isblank(name[strlen(name) - 1])) {
+        name[strlen(name) - 1] = '\0';
+    }
+
+    /* Validate name, spaces are not allowed. */
+    for (size_t i = 0; i < strlen(name); i++) {
+        if (isblank(name[i])) {
+            SCLogError("spaces not allowed in dataset names");
+            return 0;
+        }
+    }
+
+    return 1;
+}
+
+/** \brief wrapper around dirname that does leave input untouched */
+static void GetDirName(const char *in, char *out, size_t outs)
+{
+    if (strlen(in) == 0) {
+        return;
+    }
+
+    size_t size = strlen(in) + 1;
+    char tmp[size];
+    strlcpy(tmp, in, size);
+
+    char *dir = dirname(tmp);
+    BUG_ON(dir == NULL);
+    strlcpy(out, dir, outs);
+    return;
+}
+
+static int SetupLoadPath(const DetectEngineCtx *de_ctx,
+        char *load, size_t load_size)
+{
+    SCLogDebug("load %s", load);
+
+    if (PathIsAbsolute(load)) {
+        return 0;
+    }
+
+    bool done = false;
+#ifdef HAVE_LIBGEN_H
+    BUG_ON(de_ctx->rule_file == NULL);
+
+    char dir[PATH_MAX] = "";
+    GetDirName(de_ctx->rule_file, dir, sizeof(dir));
+
+    SCLogDebug("rule_file %s dir %s", de_ctx->rule_file, dir);
+    char path[PATH_MAX];
+    if (snprintf(path, sizeof(path), "%s/%s", dir, load) >= (int)sizeof(path)) // TODO windows path
+        return -1;
+
+    if (SCPathExists(path)) {
+        done = true;
+        strlcpy(load, path, load_size);
+        SCLogDebug("using path '%s' (HAVE_LIBGEN_H)", load);
+    } else {
+        SCLogDebug("path '%s' does not exist (HAVE_LIBGEN_H)", path);
+    }
+#endif
+    if (!done) {
+        char *loadp = DetectLoadCompleteSigPath(de_ctx, load);
+        if (loadp == NULL) {
+            return -1;
+        }
+        SCLogDebug("loadp %s", loadp);
+
+        if (SCPathExists(loadp)) {
+            strlcpy(load, loadp, load_size);
+            SCLogDebug("using path '%s' (non-HAVE_LIBGEN_H)", load);
+        } else {
+            SCLogDebug("path '%s' does not exist (non-HAVE_LIBGEN_H)", loadp);
+        }
+        SCFree(loadp);
+
+        // TODO try data-dir as well?
+    }
+    return 0;
+}
+
+static int DetectDatarepSetup (DetectEngineCtx *de_ctx, Signature *s, const char *rawstr)
+{
+    SigMatch *sm = NULL;
+    char cmd_str[16] = "", name[64] = "";
+    enum DatasetTypes type = DATASET_TYPE_NOTSET;
+    char load[PATH_MAX] = "";
+    uint16_t value = 0;
+    uint64_t memcap = 0;
+    uint32_t hashsize = 0;
+
+    if (DetectBufferGetActiveList(de_ctx, s) == -1) {
+        SCLogError("datarep is only supported for sticky buffers");
+        SCReturnInt(-1);
+    }
+
+    int list = s->init_data->list;
+    if (list == DETECT_SM_LIST_NOTSET) {
+        SCLogError("datarep is only supported for sticky buffers");
+        SCReturnInt(-1);
+    }
+
+    if (!DetectDatarepParse(rawstr, cmd_str, sizeof(cmd_str), name, sizeof(name), &type, load,
+                sizeof(load), &value, &memcap, &hashsize)) {
+        return -1;
+    }
+
+    if (strlen(load) != 0) {
+        if (SetupLoadPath(de_ctx, load, sizeof(load)) != 0)
+            return -1;
+    }
+
+    enum DetectDatarepOp op;
+    if (strcmp(cmd_str,">") == 0) {
+        op = DATAREP_OP_GT;
+    } else if (strcmp(cmd_str,"<") == 0) {
+        op = DATAREP_OP_LT;
+    } else if (strcmp(cmd_str,"==") == 0) {
+        op = DATAREP_OP_EQ;
+    } else {
+        SCLogError("datarep operation \"%s\" is not supported.", cmd_str);
+        return -1;
+    }
+
+    Dataset *set = DatasetGet(name, type, /* no save */ NULL, load, memcap, hashsize);
+    if (set == NULL) {
+        SCLogError("failed to set up datarep set '%s'.", name);
+        return -1;
+    }
+
+    DetectDatarepData *cd = SCCalloc(1, sizeof(DetectDatarepData));
+    if (unlikely(cd == NULL))
+        goto error;
+
+    cd->set = set;
+    cd->op = op;
+    cd->rep.value = value;
+
+    SCLogDebug("cmd %s, name %s",
+        cmd_str, strlen(name) ? name : "(none)");
+
+    /* 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_DATAREP;
+    sm->ctx = (SigMatchCtx *)cd;
+    SigMatchAppendSMToList(s, sm, list);
+    return 0;
+
+error:
+    if (cd != NULL)
+        SCFree(cd);
+    if (sm != NULL)
+        SCFree(sm);
+    return -1;
+}
+
+void DetectDatarepFree (DetectEngineCtx *de_ctx, void *ptr)
+{
+    DetectDatarepData *fd = (DetectDatarepData *)ptr;
+
+    if (fd == NULL)
+        return;
+
+    SCFree(fd);
+}