|
|
|
/* 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>
|
|
|
|
*
|
|
|
|
*/
|
|
|
|
|
|
|
|
#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-spm-bm.h"
|
|
|
|
#include "util-unittest.h"
|
|
|
|
#include "util-unittest-helper.h"
|
|
|
|
|
|
|
|
#include "app-layer.h"
|
|
|
|
|
|
|
|
#include "stream-tcp.h"
|
|
|
|
|
|
|
|
#include "detect-filename.h"
|
|
|
|
|
|
|
|
/**
|
|
|
|
* \brief Regex for parsing the protoversion string
|
|
|
|
*/
|
|
|
|
#define PARSE_REGEX "^\\s*\"?\\s*(.+)\\s*\"?\\s*$"
|
|
|
|
|
|
|
|
static pcre *parse_regex;
|
|
|
|
static pcre_extra *parse_regex_study;
|
|
|
|
|
|
|
|
int DetectFilenameMatch (ThreadVars *, DetectEngineThreadCtx *, Flow *, uint8_t, void *, Signature *, SigMatch *);
|
|
|
|
static int DetectFilenameSetup (DetectEngineCtx *, Signature *, char *);
|
|
|
|
void DetectFilenameRegisterTests(void);
|
|
|
|
void DetectFilenameFree(void *);
|
|
|
|
|
|
|
|
/**
|
|
|
|
* \brief Registration function for keyword: filename
|
|
|
|
*/
|
|
|
|
void DetectFilenameRegister(void) {
|
|
|
|
sigmatch_table[DETECT_FILENAME].name = "filename";
|
|
|
|
sigmatch_table[DETECT_FILENAME].Match = NULL;
|
|
|
|
sigmatch_table[DETECT_FILENAME].AppLayerMatch = DetectFilenameMatch;
|
|
|
|
sigmatch_table[DETECT_FILENAME].alproto = ALPROTO_HTTP;
|
|
|
|
sigmatch_table[DETECT_FILENAME].Setup = DetectFilenameSetup;
|
|
|
|
sigmatch_table[DETECT_FILENAME].Free = DetectFilenameFree;
|
|
|
|
sigmatch_table[DETECT_FILENAME].RegisterTests = DetectFilenameRegisterTests;
|
|
|
|
|
|
|
|
const char *eb;
|
|
|
|
int eo;
|
|
|
|
int opts = 0;
|
|
|
|
|
|
|
|
SCLogDebug("registering filename rule option");
|
|
|
|
|
|
|
|
parse_regex = pcre_compile(PARSE_REGEX, opts, &eb, &eo, NULL);
|
|
|
|
if (parse_regex == NULL) {
|
|
|
|
SCLogError(SC_ERR_PCRE_COMPILE, "Compile of \"%s\" failed at offset %" PRId32 ": %s",
|
|
|
|
PARSE_REGEX, eo, eb);
|
|
|
|
goto error;
|
|
|
|
}
|
|
|
|
|
|
|
|
parse_regex_study = pcre_study(parse_regex, 0, &eb);
|
|
|
|
if (eb != NULL) {
|
|
|
|
SCLogError(SC_ERR_PCRE_STUDY, "pcre study failed: %s", eb);
|
|
|
|
goto error;
|
|
|
|
}
|
|
|
|
return;
|
|
|
|
|
|
|
|
error:
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* \brief match the specified filename
|
|
|
|
*
|
|
|
|
* \param t pointer to thread vars
|
|
|
|
* \param det_ctx pointer to the pattern matcher thread
|
|
|
|
* \param p pointer to the current packet
|
|
|
|
* \param m pointer to the sigmatch that we will cast into DetectFilenameData
|
|
|
|
*
|
|
|
|
* \retval 0 no match
|
|
|
|
* \retval 1 match
|
|
|
|
*/
|
|
|
|
int DetectFilenameMatch (ThreadVars *t, DetectEngineThreadCtx *det_ctx, Flow *f, uint8_t flags, void *state, Signature *s, SigMatch *m)
|
|
|
|
{
|
|
|
|
SCEnter();
|
|
|
|
int ret = 0;
|
|
|
|
|
|
|
|
DetectFilenameData *filename = m->ctx;
|
|
|
|
|
|
|
|
SCMutexLock(&f->files_m);
|
|
|
|
if (f->files != NULL && f->files->cnt > 0) {
|
|
|
|
FlowFile *file = f->files->start;
|
|
|
|
for (; file != NULL; file = file->next) {
|
|
|
|
if (file != NULL && file->name != NULL &&
|
|
|
|
BoyerMooreNocase(filename->name, filename->len, file->name,
|
|
|
|
file->name_len, filename->bm_ctx->bmGs, filename->bm_ctx->bmBc) != NULL)
|
|
|
|
{
|
|
|
|
ret = 1;
|
|
|
|
SCLogDebug("File %s found", file->name);
|
|
|
|
/* Stop searching */
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
SCMutexUnlock(&f->files_m);
|
|
|
|
|
|
|
|
SCReturnInt(ret);
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* \brief This function is used to parse IPV4 ip_id passed via keyword: "id"
|
|
|
|
*
|
|
|
|
* \param idstr Pointer to the user provided id option
|
|
|
|
*
|
|
|
|
* \retval filename pointer to DetectFilenameData on success
|
|
|
|
* \retval NULL on failure
|
|
|
|
*/
|
|
|
|
DetectFilenameData *DetectFilenameParse (char *str)
|
|
|
|
{
|
|
|
|
DetectFilenameData *filename = NULL;
|
|
|
|
#define MAX_SUBSTRINGS 30
|
|
|
|
int ret = 0, res = 0;
|
|
|
|
int ov[MAX_SUBSTRINGS];
|
|
|
|
|
|
|
|
ret = pcre_exec(parse_regex, parse_regex_study, str, strlen(str), 0, 0,
|
|
|
|
ov, MAX_SUBSTRINGS);
|
|
|
|
|
|
|
|
if (ret < 1 || ret > 3) {
|
|
|
|
SCLogError(SC_ERR_PCRE_MATCH, "invalid filename option");
|
|
|
|
goto error;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (ret > 1) {
|
|
|
|
const char *str_ptr;
|
|
|
|
res = pcre_get_substring((char *)str, ov, MAX_SUBSTRINGS, 1, &str_ptr);
|
|
|
|
if (res < 0) {
|
|
|
|
SCLogError(SC_ERR_PCRE_GET_SUBSTRING, "pcre_get_substring failed");
|
|
|
|
goto error;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* We have a correct filename option */
|
|
|
|
filename = SCMalloc(sizeof(DetectFilenameData));
|
|
|
|
if (filename == NULL)
|
|
|
|
goto error;
|
|
|
|
|
|
|
|
memset(filename, 0x00, sizeof(DetectFilenameData));
|
|
|
|
|
|
|
|
/* Remove quotes if any and copy the filename */
|
|
|
|
if (str_ptr[0] == '\"') {
|
|
|
|
filename->name = (uint8_t *)SCStrdup((char*)str_ptr + 1);
|
|
|
|
} else {
|
|
|
|
filename->name = (uint8_t *)SCStrdup((char*)str_ptr);
|
|
|
|
}
|
|
|
|
if (filename->name[strlen((char *)filename->name) - 1] == '\"') {
|
|
|
|
filename->name[strlen((char *)filename->name) - 1] = '\0';
|
|
|
|
}
|
|
|
|
|
|
|
|
if (filename->name == NULL) {
|
|
|
|
goto error;
|
|
|
|
}
|
|
|
|
|
|
|
|
filename->len = strlen((char *) filename->name);
|
|
|
|
filename->bm_ctx = BoyerMooreCtxInit(filename->name, filename->len);
|
|
|
|
if (filename->bm_ctx == NULL) {
|
|
|
|
goto error;
|
|
|
|
}
|
|
|
|
BoyerMooreCtxToNocase(filename->bm_ctx, filename->name, filename->len);
|
|
|
|
|
|
|
|
SCLogDebug("will look for filename %s", filename->name);
|
|
|
|
}
|
|
|
|
|
|
|
|
return filename;
|
|
|
|
|
|
|
|
error:
|
|
|
|
if (filename != NULL)
|
|
|
|
DetectFilenameFree(filename);
|
|
|
|
return NULL;
|
|
|
|
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* \brief this function is used to parse filename 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 "filename" option
|
|
|
|
*
|
|
|
|
* \retval 0 on Success
|
|
|
|
* \retval -1 on Failure
|
|
|
|
*/
|
|
|
|
static int DetectFilenameSetup (DetectEngineCtx *de_ctx, Signature *s, char *str)
|
|
|
|
{
|
|
|
|
DetectFilenameData *filename = NULL;
|
|
|
|
SigMatch *sm = NULL;
|
|
|
|
|
|
|
|
filename = DetectFilenameParse(str);
|
|
|
|
if (filename == 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_FILENAME;
|
|
|
|
sm->ctx = (void *)filename;
|
|
|
|
|
|
|
|
SigMatchAppendAppLayer(s, sm);
|
|
|
|
|
|
|
|
if (s->alproto != ALPROTO_UNKNOWN && s->alproto != ALPROTO_HTTP) {
|
|
|
|
SCLogError(SC_ERR_CONFLICTING_RULE_KEYWORDS, "rule contains conflicting keywords.");
|
|
|
|
goto error;
|
|
|
|
}
|
|
|
|
|
|
|
|
AppLayerHtpNeedFileInspection();
|
|
|
|
|
|
|
|
s->alproto = ALPROTO_HTTP;
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
error:
|
|
|
|
if (filename != NULL)
|
|
|
|
DetectFilenameFree(filename);
|
|
|
|
if (sm != NULL)
|
|
|
|
SCFree(sm);
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* \brief this function will free memory associated with DetectFilenameData
|
|
|
|
*
|
|
|
|
* \param filename pointer to DetectFilenameData
|
|
|
|
*/
|
|
|
|
void DetectFilenameFree(void *ptr) {
|
|
|
|
if (ptr != NULL) {
|
|
|
|
DetectFilenameData *filename = (DetectFilenameData *)ptr;
|
|
|
|
if (filename->bm_ctx != NULL) {
|
|
|
|
BoyerMooreCtxDeInit(filename->bm_ctx);
|
|
|
|
}
|
|
|
|
SCFree(filename);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
#ifdef UNITTESTS /* UNITTESTS */
|
|
|
|
|
|
|
|
/**
|
|
|
|
* \test DetectFilenameTestParse01
|
|
|
|
*/
|
|
|
|
int DetectFilenameTestParse01 (void) {
|
|
|
|
DetectFilenameData *dnd = DetectFilenameParse("secret.pdf");
|
|
|
|
if (dnd != NULL) {
|
|
|
|
DetectFilenameFree(dnd);
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* \test DetectFilenameTestParse02
|
|
|
|
*/
|
|
|
|
int DetectFilenameTestParse02 (void) {
|
|
|
|
int result = 0;
|
|
|
|
|
|
|
|
DetectFilenameData *dnd = DetectFilenameParse("\"backup.tar.gz\"");
|
|
|
|
if (dnd != NULL) {
|
|
|
|
if (dnd->len == 13 && memcmp(dnd->name, "backup.tar.gz", 13) == 0) {
|
|
|
|
result = 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
DetectFilenameFree(dnd);
|
|
|
|
return result;
|
|
|
|
}
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* \test DetectFilenameTestParse03
|
|
|
|
*/
|
|
|
|
int DetectFilenameTestParse03 (void) {
|
|
|
|
int result = 0;
|
|
|
|
|
|
|
|
DetectFilenameData *dnd = DetectFilenameParse("cmd.exe");
|
|
|
|
if (dnd != NULL) {
|
|
|
|
if (dnd->len == 7 && memcmp(dnd->name, "cmd.exe", 7) == 0) {
|
|
|
|
result = 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
DetectFilenameFree(dnd);
|
|
|
|
return result;
|
|
|
|
}
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
#endif /* UNITTESTS */
|
|
|
|
|
|
|
|
/**
|
|
|
|
* \brief this function registers unit tests for DetectFilename
|
|
|
|
*/
|
|
|
|
void DetectFilenameRegisterTests(void) {
|
|
|
|
#ifdef UNITTESTS /* UNITTESTS */
|
|
|
|
UtRegisterTest("DetectFilenameTestParse01", DetectFilenameTestParse01, 1);
|
|
|
|
UtRegisterTest("DetectFilenameTestParse02", DetectFilenameTestParse02, 1);
|
|
|
|
UtRegisterTest("DetectFilenameTestParse03", DetectFilenameTestParse03, 1);
|
|
|
|
#endif /* UNITTESTS */
|
|
|
|
}
|