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, 591 insertions, 0 deletions

diff --git a/src/detect-isdataat.c b/src/detect-isdataat.c
new file mode 100644
index 0000000..e0858f1
--- /dev/null
+++ b/src/detect-isdataat.c
@@ -0,0 +1,591 @@
+/* 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 Pablo Rincon <pablo.rincon.crespo@gmail.com>
+ *
+ * Implements isdataat keyword
+ */
+
+#include "suricata-common.h"
+#include "decode.h"
+#include "detect.h"
+#include "detect-engine.h"
+#include "detect-parse.h"
+#include "app-layer.h"
+
+#include "util-unittest.h"
+#include "util-unittest-helper.h"
+
+#include "detect-isdataat.h"
+#include "detect-content.h"
+#include "detect-uricontent.h"
+#include "detect-engine-build.h"
+
+#include "flow.h"
+#include "flow-var.h"
+
+#include "util-debug.h"
+#include "util-byte.h"
+#include "detect-pcre.h"
+#include "detect-byte.h"
+
+/**
+ * \brief Regex for parsing our isdataat options
+ */
+#define PARSE_REGEX  "^\\s*!?([^\\s,]+)\\s*(,\\s*relative)?\\s*(,\\s*rawbytes\\s*)?\\s*$"
+
+static DetectParseRegex parse_regex;
+
+int DetectIsdataatSetup (DetectEngineCtx *, Signature *, const char *);
+#ifdef UNITTESTS
+static void DetectIsdataatRegisterTests(void);
+#endif
+void DetectIsdataatFree(DetectEngineCtx *, void *);
+
+static int DetectEndsWithSetup (DetectEngineCtx *de_ctx, Signature *s, const char *nullstr);
+
+/**
+ * \brief Registration function for isdataat: keyword
+ */
+void DetectIsdataatRegister(void)
+{
+    sigmatch_table[DETECT_ISDATAAT].name = "isdataat";
+    sigmatch_table[DETECT_ISDATAAT].desc = "check if there is still data at a specific part of the payload";
+    sigmatch_table[DETECT_ISDATAAT].url = "/rules/payload-keywords.html#isdataat";
+    /* match is handled in DetectEngineContentInspection() */
+    sigmatch_table[DETECT_ISDATAAT].Match = NULL;
+    sigmatch_table[DETECT_ISDATAAT].Setup = DetectIsdataatSetup;
+    sigmatch_table[DETECT_ISDATAAT].Free  = DetectIsdataatFree;
+#ifdef UNITTESTS
+    sigmatch_table[DETECT_ISDATAAT].RegisterTests = DetectIsdataatRegisterTests;
+#endif
+    sigmatch_table[DETECT_ENDS_WITH].name = "endswith";
+    sigmatch_table[DETECT_ENDS_WITH].desc = "make sure the previous content matches exactly at the end of the buffer";
+    sigmatch_table[DETECT_ENDS_WITH].url = "/rules/payload-keywords.html#endswith";
+    sigmatch_table[DETECT_ENDS_WITH].Setup = DetectEndsWithSetup;
+    sigmatch_table[DETECT_ENDS_WITH].flags = SIGMATCH_NOOPT;
+
+    DetectSetupParseRegexes(PARSE_REGEX, &parse_regex);
+}
+
+/**
+ * \brief This function is used to parse isdataat options passed via isdataat: keyword
+ *
+ * \param de_ctx Pointer to the detection engine context
+ * \param isdataatstr Pointer to the user provided isdataat options
+ *
+ * \retval idad pointer to DetectIsdataatData on success
+ * \retval NULL on failure
+ */
+static DetectIsdataatData *DetectIsdataatParse (DetectEngineCtx *de_ctx, const char *isdataatstr, char **offset)
+{
+    DetectIsdataatData *idad = NULL;
+    char *args[3] = {NULL,NULL,NULL};
+    int res = 0;
+    size_t pcre2_len;
+    int i=0;
+
+    pcre2_match_data *match = NULL;
+    int ret = DetectParsePcreExec(&parse_regex, &match, isdataatstr, 0, 0);
+    if (ret < 1 || ret > 4) {
+        SCLogError("pcre_exec parse error, ret %" PRId32 ", string %s", ret, isdataatstr);
+        goto error;
+    }
+
+    if (ret > 1) {
+        const char *str_ptr;
+        res = pcre2_substring_get_bynumber(match, 1, (PCRE2_UCHAR8 **)&str_ptr, &pcre2_len);
+        if (res < 0) {
+            SCLogError("pcre2_substring_get_bynumber failed");
+            goto error;
+        }
+        args[0] = (char *)str_ptr;
+
+
+        if (ret > 2) {
+            res = pcre2_substring_get_bynumber(match, 2, (PCRE2_UCHAR8 **)&str_ptr, &pcre2_len);
+            if (res < 0) {
+                SCLogError("pcre2_substring_get_bynumber failed");
+                goto error;
+            }
+            args[1] = (char *)str_ptr;
+        }
+        if (ret > 3) {
+            res = pcre2_substring_get_bynumber(match, 3, (PCRE2_UCHAR8 **)&str_ptr, &pcre2_len);
+            if (res < 0) {
+                SCLogError("pcre2_substring_get_bynumber failed");
+                goto error;
+            }
+            args[2] = (char *)str_ptr;
+        }
+
+        idad = SCMalloc(sizeof(DetectIsdataatData));
+        if (unlikely(idad == NULL))
+            goto error;
+
+        idad->flags = 0;
+        idad->dataat = 0;
+
+        if (args[0][0] != '-' && isalpha((unsigned char)args[0][0])) {
+            if (offset == NULL) {
+                SCLogError("isdataat supplied with "
+                           "var name for offset.  \"offset\" argument supplied to "
+                           "this function has to be non-NULL");
+                goto error;
+            }
+            *offset = SCStrdup(args[0]);
+            if (*offset == NULL)
+                goto error;
+        } else {
+            if (StringParseUint16(&idad->dataat, 10,
+                                        strlen(args[0]), args[0]) < 0 ) {
+                SCLogError("isdataat out of range");
+                SCFree(idad);
+                idad = NULL;
+                goto error;
+            }
+        }
+
+        if (args[1] !=NULL) {
+            idad->flags |= ISDATAAT_RELATIVE;
+
+            if(args[2] !=NULL)
+                idad->flags |= ISDATAAT_RAWBYTES;
+        }
+
+        if (isdataatstr[0] == '!') {
+            idad->flags |= ISDATAAT_NEGATED;
+        }
+
+        for (i = 0; i < (ret -1); i++) {
+            if (args[i] != NULL)
+                pcre2_substring_free((PCRE2_UCHAR8 *)args[i]);
+        }
+
+        pcre2_match_data_free(match);
+        return idad;
+
+    }
+
+error:
+    if (match) {
+        pcre2_match_data_free(match);
+    }
+    for (i = 0; i < (ret -1) && i < 3; i++){
+        if (args[i] != NULL)
+            pcre2_substring_free((PCRE2_UCHAR8 *)args[i]);
+    }
+
+    if (idad != NULL)
+        DetectIsdataatFree(de_ctx, idad);
+    return NULL;
+
+}
+
+/**
+ * \brief This function is used to add the parsed isdataatdata into the current
+ *        signature.
+ * \param de_ctx pointer to the Detection Engine Context
+ * \param s pointer to the Current Signature
+ * \param isdataatstr pointer to the user provided isdataat options
+ *
+ * \retval 0 on Success
+ * \retval -1 on Failure
+ */
+int DetectIsdataatSetup (DetectEngineCtx *de_ctx, Signature *s, const char *isdataatstr)
+{
+    SigMatch *sm = NULL;
+    SigMatch *prev_pm = NULL;
+    DetectIsdataatData *idad = NULL;
+    char *offset = NULL;
+    int ret = -1;
+
+    idad = DetectIsdataatParse(de_ctx, isdataatstr, &offset);
+    if (idad == NULL)
+        return -1;
+
+    int sm_list;
+    if (s->init_data->list != DETECT_SM_LIST_NOTSET) {
+        if (DetectBufferGetActiveList(de_ctx, s) == -1)
+            goto end;
+        sm_list = s->init_data->list;
+
+        if (idad->flags & ISDATAAT_RELATIVE) {
+            prev_pm = DetectGetLastSMFromLists(s, DETECT_CONTENT, DETECT_PCRE, -1);
+        }
+    } else if (idad->flags & ISDATAAT_RELATIVE) {
+        prev_pm = DetectGetLastSMFromLists(s,
+            DETECT_CONTENT, DETECT_PCRE,
+            DETECT_BYTETEST, DETECT_BYTEJUMP, DETECT_BYTE_EXTRACT,
+            DETECT_ISDATAAT, DETECT_BYTEMATH, -1);
+        if (prev_pm == NULL)
+            sm_list = DETECT_SM_LIST_PMATCH;
+        else {
+            sm_list = SigMatchListSMBelongsTo(s, prev_pm);
+            if (sm_list < 0)
+                goto end;
+        }
+    } else {
+        sm_list = DETECT_SM_LIST_PMATCH;
+    }
+
+    if (offset != NULL) {
+        DetectByteIndexType index;
+        if (!DetectByteRetrieveSMVar(offset, s, &index)) {
+            SCLogError("Unknown byte_extract var "
+                       "seen in isdataat - %s\n",
+                    offset);
+            goto end;
+        }
+        idad->dataat = index;
+        idad->flags |= ISDATAAT_OFFSET_VAR;
+        SCLogDebug("isdataat uses byte_extract with local id %u", idad->dataat);
+        SCFree(offset);
+        offset = NULL;
+    }
+
+    /* 'ends with' scenario */
+    if (prev_pm != NULL && prev_pm->type == DETECT_CONTENT &&
+        idad->dataat == 1 &&
+        (idad->flags & (ISDATAAT_RELATIVE|ISDATAAT_NEGATED)) == (ISDATAAT_RELATIVE|ISDATAAT_NEGATED))
+    {
+        DetectIsdataatFree(de_ctx, idad);
+        DetectContentData *cd = (DetectContentData *)prev_pm->ctx;
+        cd->flags |= DETECT_CONTENT_ENDS_WITH;
+        ret = 0;
+        goto end;
+    }
+
+    sm = SigMatchAlloc();
+    if (sm == NULL)
+        goto end;
+    sm->type = DETECT_ISDATAAT;
+    sm->ctx = (SigMatchCtx *)idad;
+    SigMatchAppendSMToList(s, sm, sm_list);
+
+    if (!(idad->flags & ISDATAAT_RELATIVE)) {
+        ret = 0;
+        goto end;
+    }
+
+    if (prev_pm == NULL) {
+        ret = 0;
+        goto end;
+    }
+
+    if (prev_pm->type == DETECT_CONTENT) {
+        DetectContentData *cd = (DetectContentData *)prev_pm->ctx;
+        cd->flags |= DETECT_CONTENT_RELATIVE_NEXT;
+    } else if (prev_pm->type == DETECT_PCRE) {
+        DetectPcreData *pd = (DetectPcreData *)prev_pm->ctx;
+        pd->flags |= DETECT_PCRE_RELATIVE_NEXT;
+    }
+
+    ret = 0;
+
+end:
+    if (offset)
+        SCFree(offset);
+    if (ret != 0)
+        DetectIsdataatFree(de_ctx, idad);
+    return ret;
+}
+
+/**
+ * \brief this function will free memory associated with DetectIsdataatData
+ *
+ * \param idad pointer to DetectIsdataatData
+ */
+void DetectIsdataatFree(DetectEngineCtx *de_ctx, void *ptr)
+{
+    DetectIsdataatData *idad = (DetectIsdataatData *)ptr;
+    SCFree(idad);
+}
+
+static int DetectEndsWithSetup (DetectEngineCtx *de_ctx, Signature *s, const char *nullstr)
+{
+    SigMatch *pm = NULL;
+    int ret = -1;
+
+    /* retrieve the sm to apply the depth against */
+    pm = DetectGetLastSMFromLists(s, DETECT_CONTENT, -1);
+    if (pm == NULL) {
+        SCLogError("endswith needs a "
+                   "preceding content option");
+        goto end;
+    }
+
+    /* verify other conditions. */
+    DetectContentData *cd = (DetectContentData *)pm->ctx;
+
+    cd->flags |= DETECT_CONTENT_ENDS_WITH;
+
+    ret = 0;
+ end:
+    return ret;
+}
+
+#ifdef UNITTESTS
+static int g_dce_stub_data_buffer_id = 0;
+
+/**
+ * \test DetectIsdataatTestParse01 is a test to make sure that we return a correct IsdataatData structure
+ *  when given valid isdataat opt
+ */
+static int DetectIsdataatTestParse01 (void)
+{
+    int result = 0;
+    DetectIsdataatData *idad = NULL;
+    idad = DetectIsdataatParse(NULL, "30 ", NULL);
+    if (idad != NULL) {
+        DetectIsdataatFree(NULL, idad);
+        result = 1;
+    }
+
+    return result;
+}
+
+/**
+ * \test DetectIsdataatTestParse02 is a test to make sure that we return a correct IsdataatData structure
+ *  when given valid isdataat opt
+ */
+static int DetectIsdataatTestParse02 (void)
+{
+    int result = 0;
+    DetectIsdataatData *idad = NULL;
+    idad = DetectIsdataatParse(NULL, "30 , relative", NULL);
+    if (idad != NULL && idad->flags & ISDATAAT_RELATIVE && !(idad->flags & ISDATAAT_RAWBYTES)) {
+        DetectIsdataatFree(NULL, idad);
+        result = 1;
+    }
+
+    return result;
+}
+
+/**
+ * \test DetectIsdataatTestParse03 is a test to make sure that we return a correct IsdataatData structure
+ *  when given valid isdataat opt
+ */
+static int DetectIsdataatTestParse03 (void)
+{
+    int result = 0;
+    DetectIsdataatData *idad = NULL;
+    idad = DetectIsdataatParse(NULL, "30,relative, rawbytes ", NULL);
+    if (idad != NULL && idad->flags & ISDATAAT_RELATIVE && idad->flags & ISDATAAT_RAWBYTES) {
+        DetectIsdataatFree(NULL, idad);
+        result = 1;
+    }
+
+    return result;
+}
+
+/**
+ * \test Test isdataat option for dce sig.
+ */
+static int DetectIsdataatTestParse04(void)
+{
+    Signature *s = SigAlloc();
+    FAIL_IF_NULL(s);
+
+    FAIL_IF(DetectSignatureSetAppProto(s, ALPROTO_DCERPC) < 0);
+
+    FAIL_IF_NOT(DetectIsdataatSetup(NULL, s, "30") == 0);
+    SigMatch *sm = DetectBufferGetFirstSigMatch(s, g_dce_stub_data_buffer_id);
+    FAIL_IF_NOT_NULL(sm);
+    FAIL_IF_NULL(s->init_data->smlists[DETECT_SM_LIST_PMATCH]);
+    SigFree(NULL, s);
+
+    s = SigAlloc();
+    FAIL_IF_NULL(s);
+    FAIL_IF(DetectSignatureSetAppProto(s, ALPROTO_DCERPC) < 0);
+    /* relative w/o preceeding match defaults to "pmatch" */
+    FAIL_IF_NOT(DetectIsdataatSetup(NULL, s, "30,relative") == 0);
+    sm = DetectBufferGetFirstSigMatch(s, g_dce_stub_data_buffer_id);
+    FAIL_IF_NOT_NULL(sm);
+    FAIL_IF_NULL(s->init_data->smlists[DETECT_SM_LIST_PMATCH]);
+
+    SigFree(NULL, s);
+    PASS;
+}
+
+static int DetectIsdataatTestParse06(void)
+{
+    DetectEngineCtx *de_ctx = DetectEngineCtxInit();
+    FAIL_IF(de_ctx == NULL);
+    de_ctx->flags |= DE_QUIET;
+
+    Signature *s = DetectEngineAppendSig(de_ctx, "alert tcp any any -> any any "
+                               "(msg:\"Testing bytejump_body\"; "
+                               "content:\"one\"; "
+                               "isdataat:!4,relative; sid:1;)");
+    FAIL_IF(s == NULL);
+
+    FAIL_IF(s->init_data->smlists_tail[DETECT_SM_LIST_PMATCH] == NULL);
+
+    FAIL_IF_NOT(s->init_data->smlists_tail[DETECT_SM_LIST_PMATCH]->type == DETECT_ISDATAAT);
+    DetectIsdataatData *data =
+            (DetectIsdataatData *)s->init_data->smlists_tail[DETECT_SM_LIST_PMATCH]->ctx;
+
+    FAIL_IF_NOT(data->flags & ISDATAAT_RELATIVE);
+    FAIL_IF(data->flags & ISDATAAT_RAWBYTES);
+    FAIL_IF_NOT(data->flags & ISDATAAT_NEGATED);
+
+    s = DetectEngineAppendSig(de_ctx, "alert tcp any any -> any any "
+                               "(msg:\"Testing bytejump_body\"; "
+                               "content:\"one\"; "
+                               "isdataat: !4,relative; sid:2;)");
+    FAIL_IF(s == NULL);
+
+    FAIL_IF(s->init_data->smlists_tail[DETECT_SM_LIST_PMATCH] == NULL);
+
+    FAIL_IF_NOT(s->init_data->smlists_tail[DETECT_SM_LIST_PMATCH]->type == DETECT_ISDATAAT);
+    data = (DetectIsdataatData *)s->init_data->smlists_tail[DETECT_SM_LIST_PMATCH]->ctx;
+
+    FAIL_IF_NOT(data->flags & ISDATAAT_RELATIVE);
+    FAIL_IF(data->flags & ISDATAAT_RAWBYTES);
+    FAIL_IF_NOT(data->flags & ISDATAAT_NEGATED);
+    DetectEngineCtxFree(de_ctx);
+
+    PASS;
+}
+
+/**
+ * \test DetectIsdataatTestPacket01 is a test to check matches of
+ * isdataat, and isdataat relative
+ */
+static int DetectIsdataatTestPacket01 (void)
+{
+    int result = 0;
+    uint8_t *buf = (uint8_t *)"Hi all!";
+    uint16_t buflen = strlen((char *)buf);
+    Packet *p[3];
+    p[0] = UTHBuildPacket((uint8_t *)buf, buflen, IPPROTO_TCP);
+    p[1] = UTHBuildPacket((uint8_t *)buf, buflen, IPPROTO_UDP);
+    p[2] = UTHBuildPacket((uint8_t *)buf, buflen, IPPROTO_ICMP);
+
+    if (p[0] == NULL || p[1] == NULL ||p[2] == NULL)
+        goto end;
+
+    const char *sigs[5];
+    sigs[0]= "alert ip any any -> any any (msg:\"Testing window 1\"; isdataat:6; sid:1;)";
+    sigs[1]= "alert ip any any -> any any (msg:\"Testing window 2\"; content:\"all\"; isdataat:1, relative; isdataat:6; sid:2;)";
+    sigs[2]= "alert ip any any -> any any (msg:\"Testing window 3\"; isdataat:8; sid:3;)";
+    sigs[3]= "alert ip any any -> any any (msg:\"Testing window 4\"; content:\"Hi\"; isdataat:5, relative; sid:4;)";
+    sigs[4]= "alert ip any any -> any any (msg:\"Testing window 4\"; content:\"Hi\"; isdataat:6, relative; sid:5;)";
+
+    uint32_t sid[5] = {1, 2, 3, 4, 5};
+
+    uint32_t results[3][5] = {
+                              /* packet 0 match sid 1 but should not match sid 2 */
+                              {1, 1, 0, 1, 0},
+                              /* packet 1 should not match */
+                              {1, 1, 0, 1, 0},
+                              /* packet 2 should not match */
+                              {1, 1, 0, 1, 0} };
+
+    result = UTHGenericTest(p, 3, sigs, sid, (uint32_t *) results, 5);
+
+    UTHFreePackets(p, 3);
+end:
+    return result;
+}
+
+/**
+ * \test DetectIsdataatTestPacket02 is a test to check matches of
+ * isdataat, and isdataat relative works if the previous keyword is pcre
+ * (bug 144)
+ */
+static int DetectIsdataatTestPacket02 (void)
+{
+    int result = 0;
+    uint8_t *buf = (uint8_t *)"GET /AllWorkAndNoPlayMakesWillADullBoy HTTP/1.0"
+                    "User-Agent: Wget/1.11.4"
+                    "Accept: */*"
+                    "Host: www.google.com"
+                    "Connection: Keep-Alive"
+                    "Date: Mon, 04 Jan 2010 17:29:39 GMT";
+    uint16_t buflen = strlen((char *)buf);
+    Packet *p;
+    p = UTHBuildPacket((uint8_t *)buf, buflen, IPPROTO_TCP);
+
+    if (p == NULL)
+        goto end;
+
+    char sig[] = "alert tcp any any -> any any (msg:\"pcre with"
+            " isdataat + relative\"; pcre:\"/A(ll|pp)WorkAndNoPlayMakesWillA"
+            "DullBoy/\"; isdataat:96,relative; sid:1;)";
+
+    result = UTHPacketMatchSig(p, sig);
+
+    UTHFreePacket(p);
+end:
+    return result;
+}
+
+/**
+ * \test DetectIsdataatTestPacket03 is a test to check matches of
+ * isdataat, and isdataat relative works if the previous keyword is byte_jump
+ * (bug 146)
+ */
+static int DetectIsdataatTestPacket03 (void)
+{
+    int result = 0;
+    uint8_t *buf = (uint8_t *)"GET /AllWorkAndNoPlayMakesWillADullBoy HTTP/1.0"
+                    "User-Agent: Wget/1.11.4"
+                    "Accept: */*"
+                    "Host: www.google.com"
+                    "Connection: Keep-Alive"
+                    "Date: Mon, 04 Jan 2010 17:29:39 GMT";
+    uint16_t buflen = strlen((char *)buf);
+    Packet *p;
+    p = UTHBuildPacket((uint8_t *)buf, buflen, IPPROTO_TCP);
+
+    if (p == NULL)
+        goto end;
+
+    char sig[] = "alert tcp any any -> any any (msg:\"byte_jump match = 0 "
+    "with distance content HTTP/1. relative against HTTP/1.0\"; byte_jump:1,"
+    "46,string,dec; isdataat:87,relative; sid:109; rev:1;)";
+
+    result = UTHPacketMatchSig(p, sig);
+
+    UTHFreePacket(p);
+end:
+    return result;
+}
+
+/**
+ * \brief this function registers unit tests for DetectIsdataat
+ */
+void DetectIsdataatRegisterTests(void)
+{
+    g_dce_stub_data_buffer_id = DetectBufferTypeGetByName("dce_stub_data");
+
+    UtRegisterTest("DetectIsdataatTestParse01", DetectIsdataatTestParse01);
+    UtRegisterTest("DetectIsdataatTestParse02", DetectIsdataatTestParse02);
+    UtRegisterTest("DetectIsdataatTestParse03", DetectIsdataatTestParse03);
+    UtRegisterTest("DetectIsdataatTestParse04", DetectIsdataatTestParse04);
+    UtRegisterTest("DetectIsdataatTestParse06", DetectIsdataatTestParse06);
+
+    UtRegisterTest("DetectIsdataatTestPacket01", DetectIsdataatTestPacket01);
+    UtRegisterTest("DetectIsdataatTestPacket02", DetectIsdataatTestPacket02);
+    UtRegisterTest("DetectIsdataatTestPacket03", DetectIsdataatTestPacket03);
+}
+#endif