mirror of https://github.com/OISF/suricata
You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
1431 lines
47 KiB
C
1431 lines
47 KiB
C
/* 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 Brian Rectanus <brectanu@gmail.com>
|
|
*
|
|
* Implements byte_jump keyword.
|
|
*/
|
|
|
|
#include "suricata-common.h"
|
|
#include "decode.h"
|
|
#include "detect.h"
|
|
#include "detect-parse.h"
|
|
#include "detect-engine.h"
|
|
#include "app-layer.h"
|
|
|
|
#include "detect-byte.h"
|
|
#include "detect-byte-extract.h"
|
|
#include "detect-bytejump.h"
|
|
#include "detect-content.h"
|
|
#include "detect-uricontent.h"
|
|
|
|
#include "util-byte.h"
|
|
#include "util-unittest.h"
|
|
#include "util-debug.h"
|
|
#include "util-validate.h"
|
|
#include "detect-pcre.h"
|
|
#include "detect-engine-build.h"
|
|
|
|
/**
|
|
* \brief Regex for parsing our options
|
|
*/
|
|
#define PARSE_REGEX "^\\s*" \
|
|
"([^\\s,]+\\s*,\\s*[^\\s,]+)" \
|
|
"(?:\\s*,\\s*((?:multiplier|post_offset)\\s+[^\\s,]+|[^\\s,]+))?" \
|
|
"(?:\\s*,\\s*((?:multiplier|post_offset)\\s+[^\\s,]+|[^\\s,]+))?" \
|
|
"(?:\\s*,\\s*((?:multiplier|post_offset)\\s+[^\\s,]+|[^\\s,]+))?" \
|
|
"(?:\\s*,\\s*((?:multiplier|post_offset)\\s+[^\\s,]+|[^\\s,]+))?" \
|
|
"(?:\\s*,\\s*((?:multiplier|post_offset)\\s+[^\\s,]+|[^\\s,]+))?" \
|
|
"(?:\\s*,\\s*((?:multiplier|post_offset)\\s+[^\\s,]+|[^\\s,]+))?" \
|
|
"(?:\\s*,\\s*((?:multiplier|post_offset)\\s+[^\\s,]+|[^\\s,]+))?" \
|
|
"(?:\\s*,\\s*((?:multiplier|post_offset)\\s+[^\\s,]+|[^\\s,]+))?" \
|
|
"(?:\\s*,\\s*((?:multiplier|post_offset)\\s+[^\\s,]+|[^\\s,]+))?" \
|
|
"\\s*$"
|
|
|
|
static DetectParseRegex parse_regex;
|
|
|
|
static int DetectBytejumpMatch(DetectEngineThreadCtx *det_ctx,
|
|
Packet *p, const Signature *s, const SigMatchCtx *ctx);
|
|
static DetectBytejumpData *DetectBytejumpParse(
|
|
DetectEngineCtx *de_ctx, const char *optstr, char **nbytes, char **offset);
|
|
static int DetectBytejumpSetup(DetectEngineCtx *de_ctx, Signature *s, const char *optstr);
|
|
static void DetectBytejumpFree(DetectEngineCtx*, void *ptr);
|
|
#ifdef UNITTESTS
|
|
static void DetectBytejumpRegisterTests(void);
|
|
#endif
|
|
|
|
void DetectBytejumpRegister (void)
|
|
{
|
|
sigmatch_table[DETECT_BYTEJUMP].name = "byte_jump";
|
|
sigmatch_table[DETECT_BYTEJUMP].desc = "allow the ability to select a <num of bytes> from an <offset> and move the detection pointer to that position";
|
|
sigmatch_table[DETECT_BYTEJUMP].url = "/rules/payload-keywords.html#byte-jump";
|
|
sigmatch_table[DETECT_BYTEJUMP].Match = DetectBytejumpMatch;
|
|
sigmatch_table[DETECT_BYTEJUMP].Setup = DetectBytejumpSetup;
|
|
sigmatch_table[DETECT_BYTEJUMP].Free = DetectBytejumpFree;
|
|
#ifdef UNITTESTS
|
|
sigmatch_table[DETECT_BYTEJUMP].RegisterTests = DetectBytejumpRegisterTests;
|
|
#endif
|
|
DetectSetupParseRegexes(PARSE_REGEX, &parse_regex);
|
|
}
|
|
|
|
/* 23 - This is the largest string (octal, with a zero prefix) that
|
|
* will not overflow uint64_t. The only way this length
|
|
* could be over 23 and still not overflow is if it were zero
|
|
* prefixed and we only support 1 byte of zero prefix for octal.
|
|
*
|
|
* "01777777777777777777777" = 0xffffffffffffffff
|
|
*
|
|
* 8 - Without string, the maximum byte extract count is 8.
|
|
*/
|
|
static inline bool DetectBytejumpValidateNbytesOnly(const DetectBytejumpData *data, int32_t nbytes)
|
|
{
|
|
return (data->flags & DETECT_BYTEJUMP_STRING && nbytes <= 23) || (nbytes <= 8);
|
|
}
|
|
|
|
static bool DetectBytejumpValidateNbytes(const DetectBytejumpData *data, int32_t nbytes)
|
|
{
|
|
if (!DetectBytejumpValidateNbytesOnly(data, nbytes)) {
|
|
if (data->flags & DETECT_BYTEJUMP_STRING) {
|
|
/* 23 - This is the largest string (octal, with a zero prefix) that
|
|
* will not overflow uint64_t. The only way this length
|
|
* could be over 23 and still not overflow is if it were zero
|
|
* prefixed and we only support 1 byte of zero prefix for octal.
|
|
*
|
|
* "01777777777777777777777" = 0xffffffffffffffff
|
|
*/
|
|
if (nbytes > 23) {
|
|
SCLogError("Cannot test more than 23 bytes "
|
|
"with \"string\"");
|
|
}
|
|
} else {
|
|
if (nbytes > 8) {
|
|
SCLogError("Cannot test more than 8 bytes "
|
|
"without \"string\"");
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
/** \brief Byte jump match function
|
|
* \param det_ctx thread detect engine ctx
|
|
* \param s signature
|
|
* \param m byte jump sigmatch
|
|
* \param payload ptr to the payload
|
|
* \param payload_len length of the payload
|
|
* \retval true match
|
|
* \retval false no match
|
|
*/
|
|
bool DetectBytejumpDoMatch(DetectEngineThreadCtx *det_ctx, const Signature *s,
|
|
const SigMatchCtx *ctx, const uint8_t *payload, uint32_t payload_len, uint16_t flags,
|
|
int32_t nbytes, int32_t offset)
|
|
{
|
|
SCEnter();
|
|
|
|
const DetectBytejumpData *data = (const DetectBytejumpData *)ctx;
|
|
const uint8_t *ptr = NULL;
|
|
int32_t len = 0;
|
|
uint64_t val = 0;
|
|
int extbytes;
|
|
|
|
if (payload_len == 0) {
|
|
SCReturnBool(false);
|
|
}
|
|
|
|
/* Validate the number of bytes we are testing
|
|
* If the validation is successful, we know that
|
|
* it contains a value <= 23. Thus, we can
|
|
* safely cast it when extracting bytes
|
|
*/
|
|
if (data->flags & DETECT_BYTEJUMP_NBYTES_VAR) {
|
|
if (!DetectBytejumpValidateNbytesOnly(data, nbytes)) {
|
|
SCLogDebug("Invalid byte_jump nbytes "
|
|
"seen in byte_jump - %d",
|
|
nbytes);
|
|
SCReturnBool(false);
|
|
}
|
|
}
|
|
|
|
/* Calculate the ptr value for the bytejump and length remaining in
|
|
* the packet from that point.
|
|
*/
|
|
ptr = payload;
|
|
len = payload_len;
|
|
if (flags & DETECT_BYTEJUMP_RELATIVE) {
|
|
ptr += det_ctx->buffer_offset;
|
|
len -= det_ctx->buffer_offset;
|
|
|
|
ptr += offset;
|
|
len -= offset;
|
|
|
|
/* No match if there is no relative base */
|
|
if (ptr == NULL || len <= 0) {
|
|
SCReturnBool(false);
|
|
}
|
|
}
|
|
else {
|
|
ptr += offset;
|
|
len -= offset;
|
|
}
|
|
|
|
/* Verify the to-be-extracted data is within the packet */
|
|
if (ptr < payload || nbytes > len) {
|
|
SCLogDebug("Data not within payload "
|
|
"pkt=%p, ptr=%p, len=%" PRIi32 ", nbytes=%" PRIi32,
|
|
payload, ptr, len, nbytes);
|
|
SCReturnBool(false);
|
|
}
|
|
|
|
/* Extract the byte data */
|
|
if (flags & DETECT_BYTEJUMP_STRING) {
|
|
extbytes = ByteExtractStringUint64(&val, data->base, nbytes, (const char *)ptr);
|
|
if(extbytes <= 0) {
|
|
SCLogDebug("error extracting %d bytes of string data: %d", nbytes, extbytes);
|
|
SCReturnBool(false);
|
|
}
|
|
}
|
|
else {
|
|
int endianness = (flags & DETECT_BYTEJUMP_LITTLE) ? BYTE_LITTLE_ENDIAN : BYTE_BIG_ENDIAN;
|
|
extbytes = ByteExtractUint64(&val, endianness, (uint16_t)nbytes, ptr);
|
|
if (extbytes != nbytes) {
|
|
SCLogDebug("error extracting %d bytes of numeric data: %d", nbytes, extbytes);
|
|
SCReturnBool(false);
|
|
}
|
|
}
|
|
|
|
SCLogDebug("VAL: (%" PRIu64 " x %" PRIu32 ") + %" PRIi32 " + %" PRId32, val, data->multiplier,
|
|
extbytes, data->post_offset);
|
|
|
|
/* Adjust the jump value based on flags */
|
|
val *= data->multiplier;
|
|
if (flags & DETECT_BYTEJUMP_ALIGN) {
|
|
if ((val % 4) != 0) {
|
|
val += 4 - (val % 4);
|
|
}
|
|
}
|
|
val += data->post_offset;
|
|
SCLogDebug("val: %" PRIi64 " post_offset: %" PRIi32, val, data->post_offset);
|
|
|
|
const uint8_t *jumpptr;
|
|
/* Calculate the jump location */
|
|
if (flags & DETECT_BYTEJUMP_BEGIN) {
|
|
jumpptr = payload + (int64_t)val;
|
|
SCLogDebug("NEWVAL: payload %p + %" PRIi64 " = %p\n", payload, (int64_t)val, jumpptr + val);
|
|
} else if (flags & DETECT_BYTEJUMP_END) {
|
|
jumpptr = payload + payload_len + (int64_t)val;
|
|
SCLogDebug(
|
|
"NEWVAL: payload %p + %" PRIu32 " + %" PRIi64, payload, payload_len, (int64_t)val);
|
|
} else {
|
|
jumpptr = ptr + (int64_t)val + extbytes;
|
|
SCLogDebug("NEWVAL: ptr %p + %" PRIi64 " = %p\n", ptr, val, jumpptr);
|
|
}
|
|
|
|
/* Validate that the jump location is still in the packet
|
|
* \todo Should this validate it is still in the *payload*?
|
|
*/
|
|
if (jumpptr < payload) {
|
|
jumpptr = payload;
|
|
SCLogDebug("jump location is before buffer start; resetting to buffer start");
|
|
} else if (jumpptr >= (payload + payload_len)) {
|
|
SCLogDebug("Jump location (%" PRIu64 ") is not within payload (%" PRIu32 ")",
|
|
payload_len + val, payload_len);
|
|
SCReturnBool(false);
|
|
}
|
|
|
|
#ifdef DEBUG
|
|
if (SCLogDebugEnabled()) {
|
|
const uint8_t *sptr = (flags & DETECT_BYTEJUMP_BEGIN) ? payload : ptr;
|
|
SCLogDebug("jumping %" PRId64 " bytes from %p (%08x)", val, sptr, (int)(sptr - payload));
|
|
}
|
|
#endif /* DEBUG */
|
|
|
|
/* Adjust the detection context to the jump location. */
|
|
DEBUG_VALIDATE_BUG_ON(jumpptr < payload);
|
|
det_ctx->buffer_offset = jumpptr - payload;
|
|
|
|
SCReturnBool(true);
|
|
}
|
|
|
|
static int DetectBytejumpMatch(DetectEngineThreadCtx *det_ctx,
|
|
Packet *p, const Signature *s, const SigMatchCtx *ctx)
|
|
{
|
|
const DetectBytejumpData *data = (const DetectBytejumpData *)ctx;
|
|
const uint8_t *ptr = NULL;
|
|
const uint8_t *jumpptr = NULL;
|
|
uint16_t len = 0;
|
|
uint64_t val = 0;
|
|
int extbytes;
|
|
|
|
if (p->payload_len == 0) {
|
|
return 0;
|
|
}
|
|
|
|
/* Calculate the ptr value for the bytejump and length remaining in
|
|
* the packet from that point.
|
|
*/
|
|
if (data->flags & DETECT_BYTEJUMP_RELATIVE) {
|
|
ptr = p->payload + det_ctx->buffer_offset;
|
|
DEBUG_VALIDATE_BUG_ON(p->payload_len - det_ctx->buffer_offset > UINT16_MAX);
|
|
len = (uint16_t)(p->payload_len - det_ctx->buffer_offset);
|
|
|
|
/* No match if there is no relative base */
|
|
if (ptr == NULL || len == 0) {
|
|
return 0;
|
|
}
|
|
|
|
ptr += data->offset;
|
|
len -= data->offset;
|
|
}
|
|
else {
|
|
ptr = p->payload + data->offset;
|
|
DEBUG_VALIDATE_BUG_ON(p->payload_len - data->offset > UINT16_MAX);
|
|
len = (uint16_t)(p->payload_len - data->offset);
|
|
}
|
|
|
|
/* Verify the to-be-extracted data is within the packet */
|
|
if (ptr < p->payload || data->nbytes > len) {
|
|
SCLogDebug("Data not within packet "
|
|
"payload=%p, ptr=%p, len=%d, nbytes=%d",
|
|
p->payload, ptr, len, data->nbytes);
|
|
return 0;
|
|
}
|
|
|
|
/* Extract the byte data */
|
|
if (data->flags & DETECT_BYTEJUMP_STRING) {
|
|
extbytes = ByteExtractStringUint64(&val, data->base,
|
|
data->nbytes, (const char *)ptr);
|
|
if (extbytes <= 0) {
|
|
SCLogDebug("error extracting %d bytes of string data: %d",
|
|
data->nbytes, extbytes);
|
|
return -1;
|
|
}
|
|
}
|
|
else {
|
|
int endianness = (data->flags & DETECT_BYTEJUMP_LITTLE) ? BYTE_LITTLE_ENDIAN : BYTE_BIG_ENDIAN;
|
|
extbytes = ByteExtractUint64(&val, endianness, data->nbytes, ptr);
|
|
if (extbytes != data->nbytes) {
|
|
SCLogDebug("error extracting %d bytes of numeric data: %d",
|
|
data->nbytes, extbytes);
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
//printf("VAL: (%" PRIu64 " x %" PRIu32 ") + %d + %" PRId32 "\n", val, data->multiplier, extbytes, data->post_offset);
|
|
|
|
/* Adjust the jump value based on flags */
|
|
val *= data->multiplier;
|
|
if (data->flags & DETECT_BYTEJUMP_ALIGN) {
|
|
if ((val % 4) != 0) {
|
|
val += 4 - (val % 4);
|
|
}
|
|
}
|
|
val += data->post_offset;
|
|
|
|
/* Calculate the jump location */
|
|
if (data->flags & DETECT_BYTEJUMP_BEGIN) {
|
|
jumpptr = p->payload + val;
|
|
//printf("NEWVAL: payload %p + %ld = %p\n", p->payload, val, jumpptr);
|
|
}
|
|
else {
|
|
val += extbytes;
|
|
jumpptr = ptr + val;
|
|
//printf("NEWVAL: ptr %p + %ld = %p\n", ptr, val, jumpptr);
|
|
}
|
|
|
|
|
|
/* Validate that the jump location is still in the packet
|
|
* \todo Should this validate it is still in the *payload*?
|
|
*/
|
|
if ((jumpptr < p->payload) || (jumpptr >= p->payload + p->payload_len)) {
|
|
SCLogDebug("Jump location (%p) is not within "
|
|
"packet (%p-%p)", jumpptr, p->payload, p->payload + p->payload_len - 1);
|
|
return 0;
|
|
}
|
|
|
|
#ifdef DEBUG
|
|
if (SCLogDebugEnabled()) {
|
|
const uint8_t *sptr = (data->flags & DETECT_BYTEJUMP_BEGIN) ? p->payload
|
|
: ptr;
|
|
SCLogDebug("jumping %" PRId64 " bytes from %p (%08x) to %p (%08x)",
|
|
val, sptr, (int)(sptr - p->payload),
|
|
jumpptr, (int)(jumpptr - p->payload));
|
|
}
|
|
#endif /* DEBUG */
|
|
|
|
/* Adjust the detection context to the jump location. */
|
|
det_ctx->buffer_offset = jumpptr - p->payload;
|
|
|
|
return 1;
|
|
}
|
|
|
|
static DetectBytejumpData *DetectBytejumpParse(
|
|
DetectEngineCtx *de_ctx, const char *optstr, char **nbytes_str, char **offset)
|
|
{
|
|
DetectBytejumpData *data = NULL;
|
|
char args[10][64];
|
|
int res = 0;
|
|
size_t pcre2len;
|
|
int numargs = 0;
|
|
int i = 0;
|
|
uint32_t nbytes = 0;
|
|
char *str_ptr;
|
|
char *end_ptr;
|
|
pcre2_match_data *match = NULL;
|
|
|
|
memset(args, 0x00, sizeof(args));
|
|
|
|
/* Execute the regex and populate args with captures. */
|
|
int ret = DetectParsePcreExec(&parse_regex, &match, optstr, 0, 0);
|
|
if (ret < 2 || ret > 10) {
|
|
SCLogError("parse error, ret %" PRId32 ", string \"%s\"", ret, optstr);
|
|
goto error;
|
|
}
|
|
|
|
/* The first two arguments are stashed in the first PCRE substring.
|
|
* This is because byte_jump can take 10 arguments, but PCRE only
|
|
* supports 9 substrings, sigh.
|
|
*/
|
|
char str[512] = "";
|
|
pcre2len = sizeof(str);
|
|
res = pcre2_substring_copy_bynumber(match, 1, (PCRE2_UCHAR8 *)str, &pcre2len);
|
|
if (res < 0) {
|
|
SCLogError("pcre2_substring_copy_bynumber failed "
|
|
"for arg 1");
|
|
goto error;
|
|
}
|
|
|
|
/* Break up first substring into two parameters
|
|
*
|
|
* NOTE: Because of this, we cannot free args[1] as it is part of args[0],
|
|
* and *yes* this *is* ugly.
|
|
*/
|
|
end_ptr = str;
|
|
while (!(isspace((unsigned char)*end_ptr) || (*end_ptr == ','))) end_ptr++;
|
|
*(end_ptr++) = '\0';
|
|
strlcpy(args[0], str, sizeof(args[0]));
|
|
numargs++;
|
|
|
|
str_ptr = end_ptr;
|
|
while (isspace((unsigned char)*str_ptr) || (*str_ptr == ',')) str_ptr++;
|
|
end_ptr = str_ptr;
|
|
while (!(isspace((unsigned char)*end_ptr) || (*end_ptr == ',')) && (*end_ptr != '\0'))
|
|
end_ptr++;
|
|
*(end_ptr++) = '\0';
|
|
strlcpy(args[1], str_ptr, sizeof(args[1]));
|
|
numargs++;
|
|
|
|
/* The remaining args are directly from PCRE substrings */
|
|
for (i = 1; i < (ret - 1); i++) {
|
|
pcre2len = sizeof(args[0]);
|
|
res = pcre2_substring_copy_bynumber(match, i + 1, (PCRE2_UCHAR8 *)args[i + 1], &pcre2len);
|
|
if (res < 0) {
|
|
SCLogError("pcre2_substring_copy_bynumber failed for arg %d", i + 1);
|
|
goto error;
|
|
}
|
|
numargs++;
|
|
}
|
|
|
|
/* Initialize the data */
|
|
data = SCMalloc(sizeof(DetectBytejumpData));
|
|
if (unlikely(data == NULL))
|
|
goto error;
|
|
data->base = DETECT_BYTEJUMP_BASE_UNSET;
|
|
data->flags = 0;
|
|
data->multiplier = 1;
|
|
data->post_offset = 0;
|
|
|
|
/*
|
|
* The first two options are required and positional. The
|
|
* remaining arguments are flags and are not positional.
|
|
*/
|
|
|
|
/* Number of bytes */
|
|
if (args[0][0] != '-' && isalpha((unsigned char)args[0][0])) {
|
|
if (nbytes_str == NULL) {
|
|
SCLogError("byte_jump supplied with "
|
|
"var name for nbytes. \"value\" argument supplied to "
|
|
"this function has to be non-NULL");
|
|
goto error;
|
|
}
|
|
*nbytes_str = SCStrdup(args[0]);
|
|
if (*nbytes_str == NULL)
|
|
goto error;
|
|
data->flags |= DETECT_BYTEJUMP_NBYTES_VAR;
|
|
} else {
|
|
if (StringParseUint32(&nbytes, 10, (uint16_t)strlen(args[0]), args[0]) <= 0) {
|
|
SCLogError("Malformed number of bytes: %s", optstr);
|
|
goto error;
|
|
}
|
|
}
|
|
|
|
/* Offset */
|
|
if (args[1][0] != '-' && isalpha((unsigned char)args[1][0])) {
|
|
if (offset == NULL) {
|
|
SCLogError("byte_jump supplied with "
|
|
"var name for offset. \"value\" argument supplied to "
|
|
"this function has to be non-NULL");
|
|
goto error;
|
|
}
|
|
*offset = SCStrdup(args[1]);
|
|
if (*offset == NULL)
|
|
goto error;
|
|
} else {
|
|
if (StringParseI32RangeCheck(
|
|
&data->offset, 10, (uint16_t)strlen(args[1]), args[1], -65535, 65535) <= 0) {
|
|
SCLogError("Malformed offset: %s", optstr);
|
|
goto error;
|
|
}
|
|
}
|
|
|
|
/* The remaining options are flags. */
|
|
/** \todo Error on dups? */
|
|
for (i = 2; i < numargs; i++) {
|
|
if (strcmp("relative", args[i]) == 0) {
|
|
data->flags |= DETECT_BYTEJUMP_RELATIVE;
|
|
} else if (strcasecmp("string", args[i]) == 0) {
|
|
data->flags |= DETECT_BYTEJUMP_STRING;
|
|
} else if (strcasecmp("dec", args[i]) == 0) {
|
|
data->base |= DETECT_BYTEJUMP_BASE_DEC;
|
|
} else if (strcasecmp("hex", args[i]) == 0) {
|
|
data->base |= DETECT_BYTEJUMP_BASE_HEX;
|
|
} else if (strcasecmp("oct", args[i]) == 0) {
|
|
data->base |= DETECT_BYTEJUMP_BASE_OCT;
|
|
} else if (strcasecmp("big", args[i]) == 0) {
|
|
if (data->flags & DETECT_BYTEJUMP_LITTLE) {
|
|
data->flags ^= DETECT_BYTEJUMP_LITTLE;
|
|
}
|
|
data->flags |= DETECT_BYTEJUMP_BIG;
|
|
} else if (strcasecmp("little", args[i]) == 0) {
|
|
data->flags |= DETECT_BYTEJUMP_LITTLE;
|
|
} else if (strcasecmp("from_beginning", args[i]) == 0) {
|
|
data->flags |= DETECT_BYTEJUMP_BEGIN;
|
|
} else if (strcasecmp("from_end", args[i]) == 0) {
|
|
data->flags |= DETECT_BYTEJUMP_END;
|
|
} else if (strcasecmp("align", args[i]) == 0) {
|
|
data->flags |= DETECT_BYTEJUMP_ALIGN;
|
|
} else if (strncasecmp("multiplier ", args[i], 11) == 0) {
|
|
if (StringParseU16RangeCheck(&data->multiplier, 10, (uint16_t)strlen(args[i]) - 11,
|
|
args[i] + 11, 1, 65535) <= 0) {
|
|
SCLogError("Malformed multiplier: %s", optstr);
|
|
goto error;
|
|
}
|
|
} else if (strncasecmp("post_offset ", args[i], 12) == 0) {
|
|
if (StringParseI32RangeCheck(&data->post_offset, 10, (uint16_t)strlen(args[i]) - 12,
|
|
args[i] + 12, -65535, 65535) <= 0) {
|
|
SCLogError("Malformed post_offset: %s", optstr);
|
|
goto error;
|
|
}
|
|
SCLogDebug("post_offset: %s [%d]", optstr, data->post_offset);
|
|
} else if (strcasecmp("dce", args[i]) == 0) {
|
|
data->flags |= DETECT_BYTEJUMP_DCE;
|
|
} else {
|
|
SCLogError("Unknown option: \"%s\"", args[i]);
|
|
goto error;
|
|
}
|
|
}
|
|
|
|
if ((data->flags & DETECT_BYTEJUMP_END) && (data->flags & DETECT_BYTEJUMP_BEGIN)) {
|
|
SCLogError("'from_end' and 'from_beginning' "
|
|
"cannot be used in the same byte_jump statement");
|
|
goto error;
|
|
}
|
|
|
|
if (!(data->flags & DETECT_BYTEJUMP_NBYTES_VAR)) {
|
|
if (!DetectBytejumpValidateNbytes(data, nbytes)) {
|
|
goto error;
|
|
}
|
|
|
|
/* This is max 23 so it will fit in a byte (see validation function) */
|
|
data->nbytes = (uint8_t)nbytes;
|
|
}
|
|
if (!(data->flags & DETECT_BYTEJUMP_STRING)) {
|
|
if (data->base != DETECT_BYTEJUMP_BASE_UNSET) {
|
|
SCLogError("Cannot use a base "
|
|
"without \"string\": %s",
|
|
optstr);
|
|
goto error;
|
|
}
|
|
}
|
|
|
|
pcre2_match_data_free(match);
|
|
return data;
|
|
|
|
error:
|
|
if (offset != NULL && *offset != NULL) {
|
|
SCFree(*offset);
|
|
*offset = NULL;
|
|
}
|
|
if (nbytes_str != NULL && *nbytes_str != NULL) {
|
|
SCFree(*nbytes_str);
|
|
*nbytes_str = NULL;
|
|
}
|
|
if (data != NULL)
|
|
DetectBytejumpFree(de_ctx, data);
|
|
if (match) {
|
|
pcre2_match_data_free(match);
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
static int DetectBytejumpSetup(DetectEngineCtx *de_ctx, Signature *s, const char *optstr)
|
|
{
|
|
SigMatch *sm = NULL;
|
|
SigMatch *prev_pm = NULL;
|
|
DetectBytejumpData *data = NULL;
|
|
char *offset = NULL;
|
|
char *nbytes = NULL;
|
|
int ret = -1;
|
|
|
|
data = DetectBytejumpParse(de_ctx, optstr, &nbytes, &offset);
|
|
if (data == NULL)
|
|
goto error;
|
|
|
|
int sm_list;
|
|
if (s->init_data->list != DETECT_SM_LIST_NOTSET) {
|
|
if (DetectBufferGetActiveList(de_ctx, s) == -1)
|
|
goto error;
|
|
|
|
sm_list = s->init_data->list;
|
|
|
|
if (data->flags & DETECT_BYTEJUMP_RELATIVE) {
|
|
prev_pm = DetectGetLastSMFromLists(s, DETECT_CONTENT, DETECT_PCRE, -1);
|
|
}
|
|
} else if (data->flags & DETECT_BYTEJUMP_DCE) {
|
|
if (data->flags & DETECT_BYTEJUMP_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 error;
|
|
}
|
|
} else {
|
|
sm_list = DETECT_SM_LIST_PMATCH;
|
|
}
|
|
|
|
if (DetectSignatureSetAppProto(s, ALPROTO_DCERPC) != 0)
|
|
goto error;
|
|
|
|
} else if (data->flags & DETECT_BYTEJUMP_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 error;
|
|
}
|
|
|
|
} else {
|
|
sm_list = DETECT_SM_LIST_PMATCH;
|
|
}
|
|
|
|
if (data->flags & DETECT_BYTEJUMP_DCE) {
|
|
if ((data->flags & DETECT_BYTEJUMP_STRING) ||
|
|
(data->flags & DETECT_BYTEJUMP_LITTLE) ||
|
|
(data->flags & DETECT_BYTEJUMP_BIG) ||
|
|
(data->flags & DETECT_BYTEJUMP_BEGIN) ||
|
|
(data->flags & DETECT_BYTEJUMP_END) ||
|
|
(data->base == DETECT_BYTEJUMP_BASE_DEC) ||
|
|
(data->base == DETECT_BYTEJUMP_BASE_HEX) ||
|
|
(data->base == DETECT_BYTEJUMP_BASE_OCT) ) {
|
|
SCLogError("Invalid option. "
|
|
"A byte_jump keyword with dce holds other invalid modifiers.");
|
|
goto error;
|
|
}
|
|
}
|
|
|
|
if (nbytes != NULL) {
|
|
DetectByteIndexType index;
|
|
if (!DetectByteRetrieveSMVar(nbytes, s, &index)) {
|
|
SCLogError("Unknown byte_extract var "
|
|
"seen in byte_jump - %s",
|
|
nbytes);
|
|
goto error;
|
|
}
|
|
data->nbytes = index;
|
|
SCFree(nbytes);
|
|
nbytes = NULL;
|
|
}
|
|
|
|
if (offset != NULL) {
|
|
DetectByteIndexType index;
|
|
if (!DetectByteRetrieveSMVar(offset, s, &index)) {
|
|
SCLogError("Unknown byte_extract var "
|
|
"seen in byte_jump - %s",
|
|
offset);
|
|
goto error;
|
|
}
|
|
data->offset = index;
|
|
data->flags |= DETECT_CONTENT_OFFSET_VAR;
|
|
SCFree(offset);
|
|
offset = NULL;
|
|
}
|
|
|
|
sm = SigMatchAlloc();
|
|
if (sm == NULL)
|
|
goto error;
|
|
sm->type = DETECT_BYTEJUMP;
|
|
sm->ctx = (SigMatchCtx *)data;
|
|
SigMatchAppendSMToList(s, sm, sm_list);
|
|
|
|
if (!(data->flags & DETECT_BYTEJUMP_RELATIVE))
|
|
goto okay;
|
|
|
|
if (prev_pm == NULL)
|
|
goto okay;
|
|
|
|
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;
|
|
}
|
|
|
|
okay:
|
|
ret = 0;
|
|
return ret;
|
|
|
|
error:
|
|
if (nbytes != NULL) {
|
|
SCFree(nbytes);
|
|
}
|
|
if (offset != NULL) {
|
|
SCFree(offset);
|
|
}
|
|
DetectBytejumpFree(de_ctx, data);
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* \brief this function will free memory associated with DetectBytejumpData
|
|
*
|
|
* \param data pointer to DetectBytejumpData
|
|
*/
|
|
static void DetectBytejumpFree(DetectEngineCtx *de_ctx, void *ptr)
|
|
{
|
|
if (ptr == NULL)
|
|
return;
|
|
|
|
DetectBytejumpData *data = (DetectBytejumpData *)ptr;
|
|
SCFree(data);
|
|
}
|
|
|
|
|
|
/* UNITTESTS */
|
|
#ifdef UNITTESTS
|
|
#include "util-unittest-helper.h"
|
|
static int g_file_data_buffer_id = 0;
|
|
static int g_dce_stub_data_buffer_id = 0;
|
|
|
|
/**
|
|
* \test DetectBytejumpTestParse01 is a test to make sure that we return
|
|
* "something" when given valid bytejump opt
|
|
*/
|
|
static int DetectBytejumpTestParse01(void)
|
|
{
|
|
int result = 0;
|
|
DetectBytejumpData *data = NULL;
|
|
data = DetectBytejumpParse(NULL, "4,0", NULL, NULL);
|
|
if (data != NULL) {
|
|
DetectBytejumpFree(NULL, data);
|
|
result = 1;
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
/**
|
|
* \test DetectBytejumpTestParse02 is a test for setting the required opts
|
|
*/
|
|
static int DetectBytejumpTestParse02(void)
|
|
{
|
|
int result = 0;
|
|
DetectBytejumpData *data = NULL;
|
|
data = DetectBytejumpParse(NULL, "4, 0", NULL, NULL);
|
|
if (data != NULL) {
|
|
if ( (data->nbytes == 4)
|
|
&& (data->offset == 0)
|
|
&& (data->multiplier == 1)
|
|
&& (data->post_offset == 0)
|
|
&& (data->flags == 0)
|
|
&& (data->base == DETECT_BYTEJUMP_BASE_UNSET))
|
|
{
|
|
result = 1;
|
|
}
|
|
DetectBytejumpFree(NULL, data);
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
/**
|
|
* \test DetectBytejumpTestParse03 is a test for setting the optional flags
|
|
*/
|
|
static int DetectBytejumpTestParse03(void)
|
|
{
|
|
int result = 0;
|
|
DetectBytejumpData *data = NULL;
|
|
data = DetectBytejumpParse(NULL,
|
|
" 4,0 , relative , little, string, "
|
|
"dec, align, from_beginning",
|
|
NULL, NULL);
|
|
if (data != NULL) {
|
|
if ( (data->nbytes == 4)
|
|
&& (data->offset == 0)
|
|
&& (data->multiplier == 1)
|
|
&& (data->post_offset == 0)
|
|
&& (data->flags == ( DETECT_BYTEJUMP_RELATIVE
|
|
|DETECT_BYTEJUMP_LITTLE
|
|
|DETECT_BYTEJUMP_STRING
|
|
|DETECT_BYTEJUMP_ALIGN
|
|
|DETECT_BYTEJUMP_BEGIN))
|
|
&& (data->base == DETECT_BYTEJUMP_BASE_DEC))
|
|
{
|
|
result = 1;
|
|
}
|
|
DetectBytejumpFree(NULL, data);
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
/**
|
|
* \test DetectBytejumpTestParse04 is a test for setting the optional flags
|
|
* with parameters
|
|
*
|
|
* \todo This fails because we can only have 9 captures and there are 10.
|
|
*/
|
|
static int DetectBytejumpTestParse04(void)
|
|
{
|
|
int result = 0;
|
|
DetectBytejumpData *data = NULL;
|
|
data = DetectBytejumpParse(NULL,
|
|
" 4,0 , relative , little, string, "
|
|
"dec, align, from_beginning , "
|
|
"multiplier 2 , post_offset -16 ",
|
|
NULL, NULL);
|
|
if (data != NULL) {
|
|
if ( (data->nbytes == 4)
|
|
&& (data->offset == 0)
|
|
&& (data->multiplier == 2)
|
|
&& (data->post_offset == -16)
|
|
&& (data->flags == ( DETECT_BYTEJUMP_RELATIVE
|
|
|DETECT_BYTEJUMP_LITTLE
|
|
|DETECT_BYTEJUMP_ALIGN
|
|
|DETECT_BYTEJUMP_STRING
|
|
|DETECT_BYTEJUMP_BEGIN))
|
|
&& (data->base == DETECT_BYTEJUMP_BASE_DEC))
|
|
{
|
|
result = 1;
|
|
}
|
|
DetectBytejumpFree(NULL, data);
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
/**
|
|
* \test DetectBytejumpTestParse05 is a test for setting base without string
|
|
*/
|
|
static int DetectBytejumpTestParse05(void)
|
|
{
|
|
int result = 0;
|
|
DetectBytejumpData *data = NULL;
|
|
data = DetectBytejumpParse(NULL,
|
|
" 4,0 , relative , little, dec, "
|
|
"align, from_beginning",
|
|
NULL, NULL);
|
|
if (data == NULL) {
|
|
result = 1;
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
/**
|
|
* \test DetectBytejumpTestParse06 is a test for too many bytes to extract
|
|
*/
|
|
static int DetectBytejumpTestParse06(void)
|
|
{
|
|
int result = 0;
|
|
DetectBytejumpData *data = NULL;
|
|
data = DetectBytejumpParse(NULL, "9, 0", NULL, NULL);
|
|
if (data == NULL) {
|
|
result = 1;
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
/**
|
|
* \test DetectBytejumpTestParse07 is a test for too many string bytes to extract
|
|
*/
|
|
static int DetectBytejumpTestParse07(void)
|
|
{
|
|
int result = 0;
|
|
DetectBytejumpData *data = NULL;
|
|
data = DetectBytejumpParse(NULL, "24, 0, string, dec", NULL, NULL);
|
|
if (data == NULL) {
|
|
result = 1;
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
/**
|
|
* \test DetectBytejumpTestParse08 is a test for offset too big
|
|
*/
|
|
static int DetectBytejumpTestParse08(void)
|
|
{
|
|
int result = 0;
|
|
DetectBytejumpData *data = NULL;
|
|
data = DetectBytejumpParse(NULL, "4, 0xffffffffffffffff", NULL, NULL);
|
|
if (data == NULL) {
|
|
result = 1;
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
/**
|
|
* \test Test dce option.
|
|
*/
|
|
static int DetectBytejumpTestParse09(void)
|
|
{
|
|
Signature *s = SigAlloc();
|
|
FAIL_IF_NULL(s);
|
|
|
|
FAIL_IF(DetectSignatureSetAppProto(s, ALPROTO_DCERPC) < 0);
|
|
|
|
FAIL_IF_NOT(DetectBytejumpSetup(NULL, s,
|
|
"4,0, align, multiplier 2, "
|
|
"post_offset -16,dce") == 0);
|
|
FAIL_IF_NOT(DetectBytejumpSetup(NULL, s,
|
|
"4,0, multiplier 2, "
|
|
"post_offset -16,dce") == 0);
|
|
FAIL_IF_NOT(DetectBytejumpSetup(NULL, s, "4,0,post_offset -16,dce") == 0);
|
|
FAIL_IF_NOT(DetectBytejumpSetup(NULL, s, "4,0,dce") == 0);
|
|
FAIL_IF_NOT(DetectBytejumpSetup(NULL, s, "4,0,dce") == 0);
|
|
FAIL_IF_NOT(DetectBytejumpSetup(NULL, s, "4,0, string, dce") == -1);
|
|
FAIL_IF_NOT(DetectBytejumpSetup(NULL, s, "4,0, big, dce") == -1);
|
|
FAIL_IF_NOT(DetectBytejumpSetup(NULL, s, "4,0, little, dce") == -1);
|
|
FAIL_IF_NOT(DetectBytejumpSetup(NULL, s, "4,0, string, dec, dce") == -1);
|
|
FAIL_IF_NOT(DetectBytejumpSetup(NULL, s, "4,0, string, oct, dce") == -1);
|
|
FAIL_IF_NOT(DetectBytejumpSetup(NULL, s, "4,0, string, hex, dce") == -1);
|
|
FAIL_IF_NOT(DetectBytejumpSetup(NULL, s, "4,0, from_beginning, dce") == -1);
|
|
|
|
FAIL_IF_NULL(s->init_data->smlists[DETECT_SM_LIST_PMATCH]);
|
|
SigMatch *sm = DetectBufferGetFirstSigMatch(s, g_dce_stub_data_buffer_id);
|
|
FAIL_IF_NOT_NULL(sm);
|
|
|
|
SigFree(NULL, s);
|
|
PASS;
|
|
}
|
|
|
|
/**
|
|
* \test Test dce option.
|
|
*/
|
|
static int DetectBytejumpTestParse10(void)
|
|
{
|
|
DetectEngineCtx *de_ctx = DetectEngineCtxInit();
|
|
FAIL_IF_NULL(de_ctx);
|
|
de_ctx->flags |= DE_QUIET;
|
|
|
|
Signature *s = DetectEngineAppendSig(de_ctx, "alert tcp any any -> any any "
|
|
"(msg:\"Testing bytejump_body\"; "
|
|
"dce_iface:3919286a-b10c-11d0-9ba8-00c04fd92ef5; "
|
|
"dce_stub_data; "
|
|
"content:\"one\"; distance:0; "
|
|
"byte_jump:4,0,align,multiplier 2, "
|
|
"post_offset -16,relative,dce; sid:1;)");
|
|
FAIL_IF_NULL(s);
|
|
SigMatch *sm = DetectBufferGetFirstSigMatch(s, g_dce_stub_data_buffer_id);
|
|
FAIL_IF_NULL(sm);
|
|
FAIL_IF_NOT(sm->type == DETECT_CONTENT);
|
|
FAIL_IF_NULL(sm->next);
|
|
sm = sm->next;
|
|
FAIL_IF_NOT(sm->type == DETECT_BYTEJUMP);
|
|
|
|
DetectBytejumpData *bd = (DetectBytejumpData *)sm->ctx;
|
|
if (!(bd->flags & DETECT_BYTEJUMP_DCE) && !(bd->flags & DETECT_BYTEJUMP_RELATIVE) &&
|
|
(bd->flags & DETECT_BYTEJUMP_STRING) && (bd->flags & DETECT_BYTEJUMP_BIG) &&
|
|
(bd->flags & DETECT_BYTEJUMP_LITTLE)) {
|
|
goto end;
|
|
}
|
|
|
|
s = DetectEngineAppendSig(de_ctx, "alert tcp any any -> any any "
|
|
"(msg:\"Testing bytejump_body\"; "
|
|
"dce_iface:3919286a-b10c-11d0-9ba8-00c04fd92ef5; "
|
|
"dce_stub_data; "
|
|
"content:\"one\"; distance:0; "
|
|
"byte_jump:4,0,align,multiplier 2, "
|
|
"post_offset -16,relative,dce; sid:2;)");
|
|
FAIL_IF_NULL(s);
|
|
sm = DetectBufferGetFirstSigMatch(s, g_dce_stub_data_buffer_id);
|
|
FAIL_IF_NULL(sm);
|
|
|
|
FAIL_IF_NOT(sm->type == DETECT_CONTENT);
|
|
FAIL_IF_NULL(sm->next);
|
|
sm = sm->next;
|
|
FAIL_IF_NOT(sm->type == DETECT_BYTEJUMP);
|
|
|
|
bd = (DetectBytejumpData *)sm->ctx;
|
|
if (!(bd->flags & DETECT_BYTEJUMP_DCE) && !(bd->flags & DETECT_BYTEJUMP_RELATIVE) &&
|
|
(bd->flags & DETECT_BYTEJUMP_STRING) && (bd->flags & DETECT_BYTEJUMP_BIG) &&
|
|
(bd->flags & DETECT_BYTEJUMP_LITTLE)) {
|
|
goto end;
|
|
}
|
|
|
|
s = DetectEngineAppendSig(de_ctx, "alert tcp any any -> any any "
|
|
"(msg:\"Testing bytejump_body\"; "
|
|
"dce_iface:3919286a-b10c-11d0-9ba8-00c04fd92ef5; "
|
|
"dce_stub_data; "
|
|
"content:\"one\"; distance:0; "
|
|
"byte_jump:4,0,align,multiplier 2, "
|
|
"post_offset -16,relative; sid:3;)");
|
|
FAIL_IF_NULL(s);
|
|
sm = DetectBufferGetFirstSigMatch(s, g_dce_stub_data_buffer_id);
|
|
FAIL_IF_NULL(sm);
|
|
|
|
FAIL_IF_NOT(sm->type == DETECT_CONTENT);
|
|
FAIL_IF_NULL(sm->next);
|
|
sm = sm->next;
|
|
FAIL_IF_NOT(sm->type == DETECT_BYTEJUMP);
|
|
|
|
bd = (DetectBytejumpData *)sm->ctx;
|
|
if ((bd->flags & DETECT_BYTEJUMP_DCE) && !(bd->flags & DETECT_BYTEJUMP_RELATIVE) &&
|
|
(bd->flags & DETECT_BYTEJUMP_STRING) && (bd->flags & DETECT_BYTEJUMP_BIG) &&
|
|
(bd->flags & DETECT_BYTEJUMP_LITTLE)) {
|
|
goto end;
|
|
}
|
|
|
|
end:
|
|
DetectEngineCtxFree(de_ctx);
|
|
PASS;
|
|
}
|
|
|
|
/**
|
|
* \test Test dce option.
|
|
*/
|
|
static int DetectBytejumpTestParse11(void)
|
|
{
|
|
DetectEngineCtx *de_ctx = NULL;
|
|
int result = 1;
|
|
Signature *s = NULL;
|
|
|
|
de_ctx = DetectEngineCtxInit();
|
|
if (de_ctx == NULL)
|
|
goto end;
|
|
|
|
de_ctx->flags |= DE_QUIET;
|
|
s = SigInit(de_ctx, "alert tcp any any -> any any "
|
|
"(msg:\"Testing bytejump_body\"; "
|
|
"dce_iface:3919286a-b10c-11d0-9ba8-00c04fd92ef5; "
|
|
"dce_stub_data; "
|
|
"content:\"one\"; byte_jump:4,0,align,multiplier 2, "
|
|
"post_offset -16,string,dce; sid:1;)");
|
|
if (s != NULL) {
|
|
result = 0;
|
|
goto end;
|
|
}
|
|
|
|
s = SigInit(de_ctx, "alert tcp any any -> any any "
|
|
"(msg:\"Testing bytejump_body\"; "
|
|
"dce_iface:3919286a-b10c-11d0-9ba8-00c04fd92ef5; "
|
|
"dce_sub_data; "
|
|
"content:\"one\"; byte_jump:4,0,align,multiplier 2, "
|
|
"post_offset -16,big,dce; sid:1;)");
|
|
if (s != NULL) {
|
|
result = 0;
|
|
goto end;
|
|
}
|
|
|
|
s = SigInit(de_ctx, "alert tcp any any -> any any "
|
|
"(msg:\"Testing bytejump_body\"; "
|
|
"dce_iface:3919286a-b10c-11d0-9ba8-00c04fd92ef5; "
|
|
"dce_stub_data; "
|
|
"content:\"one\"; byte_jump:4,0,align,multiplier 2, "
|
|
"post_offset -16,little,dce; sid:1;)");
|
|
if (s != NULL) {
|
|
result = 0;
|
|
goto end;
|
|
}
|
|
|
|
s = SigInit(de_ctx, "alert tcp any any -> any any "
|
|
"(msg:\"Testing bytejump_body\"; "
|
|
"dce_iface:3919286a-b10c-11d0-9ba8-00c04fd92ef5; "
|
|
"dce_stub_data; "
|
|
"content:\"one\"; byte_jump:4,0,align,multiplier 2, "
|
|
"post_offset -16,string,hex,dce; sid:1;)");
|
|
if (s != NULL) {
|
|
result = 0;
|
|
goto end;
|
|
}
|
|
|
|
s = SigInit(de_ctx, "alert tcp any any -> any any "
|
|
"(msg:\"Testing bytejump_body\"; "
|
|
"dce_iface:3919286a-b10c-11d0-9ba8-00c04fd92ef5; "
|
|
"dce_stub_data; "
|
|
"content:\"one\"; byte_jump:4,0,align,multiplier 2, "
|
|
"post_offset -16,string,dec,dce; sid:1;)");
|
|
if (s != NULL) {
|
|
result = 0;
|
|
goto end;
|
|
}
|
|
|
|
s = SigInit(de_ctx, "alert tcp any any -> any any "
|
|
"(msg:\"Testing bytejump_body\"; "
|
|
"dce_iface:3919286a-b10c-11d0-9ba8-00c04fd92ef5; "
|
|
"dce_stub_data; "
|
|
"content:\"one\"; byte_jump:4,0,align,multiplier 2, "
|
|
"post_offset -16,string,oct,dce; sid:1;)");
|
|
if (s != NULL) {
|
|
result = 0;
|
|
goto end;
|
|
}
|
|
|
|
s = SigInit(de_ctx, "alert tcp any any -> any any "
|
|
"(msg:\"Testing bytejump_body\"; "
|
|
"dce_iface:3919286a-b10c-11d0-9ba8-00c04fd92ef5; "
|
|
"dce_stub_data; "
|
|
"content:\"one\"; byte_jump:4,0,align,multiplier 2, "
|
|
"post_offset -16,from_beginning,dce; sid:1;)");
|
|
if (s != NULL) {
|
|
result = 0;
|
|
goto end;
|
|
}
|
|
|
|
end:
|
|
SigGroupCleanup(de_ctx);
|
|
SigCleanSignatures(de_ctx);
|
|
DetectEngineCtxFree(de_ctx);
|
|
|
|
return result;
|
|
}
|
|
|
|
/**
|
|
* \test Test file_data
|
|
*/
|
|
static int DetectBytejumpTestParse12(void)
|
|
{
|
|
DetectEngineCtx *de_ctx = DetectEngineCtxInit();
|
|
FAIL_IF_NULL(de_ctx);
|
|
de_ctx->flags |= DE_QUIET;
|
|
|
|
Signature *s = DetectEngineAppendSig(de_ctx, "alert tcp any any -> any any "
|
|
"(file_data; byte_jump:4,0,align,multiplier 2, "
|
|
"post_offset -16,relative; sid:1;)");
|
|
FAIL_IF_NULL(s);
|
|
|
|
SigMatch *sm = DetectBufferGetFirstSigMatch(s, g_file_data_buffer_id);
|
|
FAIL_IF_NULL(sm);
|
|
FAIL_IF_NOT(sm->type == DETECT_BYTEJUMP);
|
|
|
|
DetectBytejumpData *bd = (DetectBytejumpData *)sm->ctx;
|
|
FAIL_IF(bd->flags & DETECT_BYTEJUMP_DCE);
|
|
FAIL_IF((bd->flags &
|
|
(DETECT_BYTEJUMP_RELATIVE | DETECT_BYTEJUMP_STRING | DETECT_BYTEJUMP_BIG)) ==
|
|
(DETECT_BYTEJUMP_RELATIVE | DETECT_BYTEJUMP_STRING | DETECT_BYTEJUMP_BIG));
|
|
|
|
DetectEngineCtxFree(de_ctx);
|
|
PASS;
|
|
}
|
|
|
|
static int DetectBytejumpTestParse13(void)
|
|
{
|
|
DetectBytejumpData *data = DetectBytejumpParse(NULL,
|
|
" 4,0 , relative , little, string, dec, "
|
|
"align, from_end",
|
|
NULL, NULL);
|
|
FAIL_IF_NULL(data);
|
|
FAIL_IF_NOT(data->flags & DETECT_BYTEJUMP_END);
|
|
|
|
DetectBytejumpFree(NULL, data);
|
|
|
|
PASS;
|
|
}
|
|
|
|
static int DetectBytejumpTestParse14(void)
|
|
{
|
|
DetectBytejumpData *data = DetectBytejumpParse(NULL,
|
|
" 4,0 , relative , little, string, dec, "
|
|
"align, from_beginning, from_end",
|
|
NULL, NULL);
|
|
|
|
FAIL_IF_NOT_NULL(data);
|
|
|
|
PASS;
|
|
}
|
|
|
|
/**
|
|
* \test DetectByteJumpTestPacket01 is a test to check matches of
|
|
* byte_jump and byte_jump relative works if the previous keyword is pcre
|
|
* (bug 142)
|
|
*/
|
|
static int DetectByteJumpTestPacket01 (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 + byte_test + "
|
|
"relative\"; pcre:\"/AllWorkAndNoPlayMakesWillADullBoy/\"; byte_jump:1,6,"
|
|
"relative,string,dec; content:\"0\"; sid:134; rev:1;)";
|
|
|
|
result = UTHPacketMatchSig(p, sig);
|
|
|
|
UTHFreePacket(p);
|
|
end:
|
|
return result;
|
|
}
|
|
|
|
/**
|
|
* \test DetectByteJumpTestPacket02 is a test to check matches of
|
|
* byte_jump and byte_jump relative works if the previous keyword is byte_jump
|
|
* (bug 165)
|
|
*/
|
|
static int DetectByteJumpTestPacket02 (void)
|
|
{
|
|
int result = 0;
|
|
uint8_t buf[] = { 0x00, 0x00, 0x00, 0x77, 0xff, 0x53,
|
|
0x4d, 0x42, 0x2f, 0x00, 0x00, 0x00, 0x00, 0x18,
|
|
0x01, 0x20, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
|
|
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x08,
|
|
0x92, 0xa4, 0x01, 0x08, 0x17, 0x5c, 0x0e, 0xff,
|
|
0x00, 0x00, 0x00, 0x01, 0x40, 0x48, 0x00, 0x00,
|
|
0x00, 0xff };
|
|
uint16_t buflen = sizeof(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 with byte_jump"
|
|
" + relative\"; byte_jump:1,13; byte_jump:4,0,relative; "
|
|
"content:\"|48 00 00|\"; within:3; sid:144; rev:1;)";
|
|
|
|
result = UTHPacketMatchSig(p, sig);
|
|
|
|
UTHFreePacket(p);
|
|
end:
|
|
return result;
|
|
}
|
|
|
|
static int DetectByteJumpTestPacket03(void)
|
|
{
|
|
int result = 0;
|
|
uint8_t *buf = NULL;
|
|
uint16_t buflen = 0;
|
|
buf = SCMalloc(4);
|
|
if (unlikely(buf == NULL)) {
|
|
printf("malloc failed\n");
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
memcpy(buf, "boom", 4);
|
|
buflen = 4;
|
|
|
|
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\"; "
|
|
"byte_jump:1,214748364; sid:1; rev:1;)";
|
|
|
|
result = !UTHPacketMatchSig(p, sig);
|
|
|
|
UTHFreePacket(p);
|
|
|
|
end:
|
|
if (buf != NULL)
|
|
SCFree(buf);
|
|
return result;
|
|
}
|
|
|
|
/**
|
|
* \test check matches of with from_beginning (bug 626/627)
|
|
*/
|
|
static int DetectByteJumpTestPacket04 (void)
|
|
{
|
|
int result = 0;
|
|
uint8_t *buf = (uint8_t *)"XYZ04abcdABCD";
|
|
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 (content:\"XYZ\"; byte_jump:2,0,relative,string,dec; content:\"ABCD\"; distance:0; within:4; sid:1; rev:1;)";
|
|
|
|
result = UTHPacketMatchSig(p, sig);
|
|
|
|
UTHFreePacket(p);
|
|
end:
|
|
return result;
|
|
}
|
|
|
|
/**
|
|
* \test check matches of with from_beginning (bug 626/627)
|
|
*/
|
|
static int DetectByteJumpTestPacket05 (void)
|
|
{
|
|
int result = 0;
|
|
uint8_t *buf = (uint8_t *)"XYZ04abcdABCD";
|
|
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 (content:\"XYZ\"; byte_jump:2,0,relative,string,dec; content:\"cdABCD\"; within:6; sid:1; rev:1;)";
|
|
|
|
result = UTHPacketMatchSig(p, sig) ? 0 : 1;
|
|
|
|
UTHFreePacket(p);
|
|
end:
|
|
return result;
|
|
}
|
|
|
|
/**
|
|
* \test check matches of with from_beginning (bug 626/627)
|
|
*/
|
|
static int DetectByteJumpTestPacket06 (void)
|
|
{
|
|
int result = 0;
|
|
uint8_t *buf = (uint8_t *)"XX04abcdABCD";
|
|
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 (content:\"XX\"; byte_jump:2,0,relative,string,dec,from_beginning; content:\"ABCD\"; distance:4; within:4; sid:1; rev:1;)";
|
|
|
|
result = UTHPacketMatchSig(p, sig);
|
|
|
|
UTHFreePacket(p);
|
|
end:
|
|
return result;
|
|
}
|
|
|
|
/**
|
|
* \test check matches of with from_beginning (bug 626/627)
|
|
*/
|
|
static int DetectByteJumpTestPacket07 (void)
|
|
{
|
|
int result = 0;
|
|
uint8_t *buf = (uint8_t *)"XX04abcdABCD";
|
|
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 (content:\"XX\"; byte_jump:2,0,relative,string,dec,from_beginning; content:\"abcdABCD\"; distance:0; within:8; sid:1; rev:1;)";
|
|
|
|
result = UTHPacketMatchSig(p, sig) ? 1 : 0;
|
|
|
|
UTHFreePacket(p);
|
|
end:
|
|
return result;
|
|
}
|
|
|
|
/**
|
|
* \test check matches of with from_end
|
|
*/
|
|
static int DetectByteJumpTestPacket08 (void)
|
|
{
|
|
uint8_t *buf = (uint8_t *)"XX04abcdABCD";
|
|
uint16_t buflen = strlen((char *)buf);
|
|
Packet *p = UTHBuildPacket((uint8_t *)buf, buflen, IPPROTO_TCP);
|
|
|
|
FAIL_IF_NULL(p);
|
|
|
|
char sig[] = "alert tcp any any -> any any (content:\"XX\"; byte_jump:2,0,"
|
|
"relative,string,dec,from_end, post_offset -8; content:\"ABCD\"; sid:1; rev:1;)";
|
|
|
|
FAIL_IF_NOT(UTHPacketMatchSig(p, sig));
|
|
|
|
UTHFreePacket(p);
|
|
|
|
PASS;
|
|
}
|
|
|
|
/**
|
|
* \brief this function registers unit tests for DetectBytejump
|
|
*/
|
|
static void DetectBytejumpRegisterTests(void)
|
|
{
|
|
g_file_data_buffer_id = DetectBufferTypeGetByName("file_data");
|
|
g_dce_stub_data_buffer_id = DetectBufferTypeGetByName("dce_stub_data");
|
|
|
|
UtRegisterTest("DetectBytejumpTestParse01", DetectBytejumpTestParse01);
|
|
UtRegisterTest("DetectBytejumpTestParse02", DetectBytejumpTestParse02);
|
|
UtRegisterTest("DetectBytejumpTestParse03", DetectBytejumpTestParse03);
|
|
UtRegisterTest("DetectBytejumpTestParse04", DetectBytejumpTestParse04);
|
|
UtRegisterTest("DetectBytejumpTestParse05", DetectBytejumpTestParse05);
|
|
UtRegisterTest("DetectBytejumpTestParse06", DetectBytejumpTestParse06);
|
|
UtRegisterTest("DetectBytejumpTestParse07", DetectBytejumpTestParse07);
|
|
UtRegisterTest("DetectBytejumpTestParse08", DetectBytejumpTestParse08);
|
|
UtRegisterTest("DetectBytejumpTestParse09", DetectBytejumpTestParse09);
|
|
UtRegisterTest("DetectBytejumpTestParse10", DetectBytejumpTestParse10);
|
|
UtRegisterTest("DetectBytejumpTestParse11", DetectBytejumpTestParse11);
|
|
UtRegisterTest("DetectBytejumpTestParse12", DetectBytejumpTestParse12);
|
|
UtRegisterTest("DetectBytejumpTestParse13", DetectBytejumpTestParse13);
|
|
UtRegisterTest("DetectBytejumpTestParse14", DetectBytejumpTestParse14);
|
|
|
|
UtRegisterTest("DetectByteJumpTestPacket01", DetectByteJumpTestPacket01);
|
|
UtRegisterTest("DetectByteJumpTestPacket02", DetectByteJumpTestPacket02);
|
|
UtRegisterTest("DetectByteJumpTestPacket03", DetectByteJumpTestPacket03);
|
|
UtRegisterTest("DetectByteJumpTestPacket04", DetectByteJumpTestPacket04);
|
|
UtRegisterTest("DetectByteJumpTestPacket05", DetectByteJumpTestPacket05);
|
|
UtRegisterTest("DetectByteJumpTestPacket06", DetectByteJumpTestPacket06);
|
|
UtRegisterTest("DetectByteJumpTestPacket07", DetectByteJumpTestPacket07);
|
|
UtRegisterTest("DetectByteJumpTestPacket08", DetectByteJumpTestPacket08);
|
|
}
|
|
#endif /* UNITTESTS */
|