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.
124 lines
4.0 KiB
C
124 lines
4.0 KiB
C
/* Copyright (C) 2026 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
|
|
*/
|
|
|
|
#include "suricata-common.h"
|
|
|
|
#include "detect.h"
|
|
#include "detect-parse.h"
|
|
#include "detect-engine.h"
|
|
#include "detect-engine-buffer.h"
|
|
#include "detect-engine-mpm.h"
|
|
#include "detect-engine-prefilter.h"
|
|
#include "detect-engine-content-inspection.h"
|
|
#include "detect-fast-pattern.h"
|
|
#include "detect-etherhdr.h"
|
|
|
|
/* prototypes */
|
|
static int DetectEtherhdrSetup(DetectEngineCtx *, Signature *, const char *);
|
|
#ifdef UNITTESTS
|
|
void DetectEtherhdrRegisterTests(void);
|
|
#endif
|
|
|
|
static int g_etherhdr_buffer_id = 0;
|
|
|
|
static InspectionBuffer *GetData(DetectEngineThreadCtx *det_ctx,
|
|
const DetectEngineTransforms *transforms, Packet *p, const int list_id);
|
|
|
|
/**
|
|
* \brief Registration function for ether.hdr: keyword
|
|
*/
|
|
void DetectEtherhdrRegister(void)
|
|
{
|
|
sigmatch_table[DETECT_ETHERHDR].name = "ether.hdr";
|
|
sigmatch_table[DETECT_ETHERHDR].desc = "sticky buffer to match on the Ethernet header";
|
|
sigmatch_table[DETECT_ETHERHDR].url = "/rules/header-keywords.html#ether-hdr";
|
|
sigmatch_table[DETECT_ETHERHDR].Setup = DetectEtherhdrSetup;
|
|
sigmatch_table[DETECT_ETHERHDR].flags |= SIGMATCH_NOOPT | SIGMATCH_INFO_STICKY_BUFFER;
|
|
#ifdef UNITTESTS
|
|
sigmatch_table[DETECT_ETHERHDR].RegisterTests = DetectEtherhdrRegisterTests;
|
|
#endif
|
|
|
|
g_etherhdr_buffer_id = DetectBufferTypeRegister("ether.hdr");
|
|
BUG_ON(g_etherhdr_buffer_id < 0);
|
|
|
|
DetectBufferTypeSupportsPacket("ether.hdr");
|
|
|
|
DetectPktMpmRegister("ether.hdr", 2, PrefilterGenericMpmPktRegister, GetData);
|
|
|
|
DetectPktInspectEngineRegister("ether.hdr", GetData, DetectEngineInspectPktBufferGeneric);
|
|
}
|
|
|
|
/**
|
|
* \brief setup ether.hdr sticky buffer
|
|
*
|
|
* \param de_ctx pointer to the Detection Engine Context
|
|
* \param s pointer to the Current Signature
|
|
* \param _unused unused
|
|
*
|
|
* \retval 0 on Success
|
|
* \retval -1 on Failure
|
|
*/
|
|
static int DetectEtherhdrSetup(DetectEngineCtx *de_ctx, Signature *s, const char *_unused)
|
|
{
|
|
s->init_data->proto.flags |= DETECT_PROTO_ETHERNET;
|
|
s->flags |= SIG_FLAG_REQUIRE_PACKET;
|
|
|
|
if (SCDetectBufferSetActiveList(de_ctx, s, g_etherhdr_buffer_id) < 0)
|
|
return -1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static InspectionBuffer *GetData(DetectEngineThreadCtx *det_ctx,
|
|
const DetectEngineTransforms *transforms, Packet *p, const int list_id)
|
|
{
|
|
SCEnter();
|
|
|
|
InspectionBuffer *buffer = SCInspectionBufferGet(det_ctx, list_id);
|
|
if (buffer->inspect == NULL) {
|
|
if (!PacketIsEthernet(p)) {
|
|
// DETECT_PROTO_ETHERNET does not prefilter
|
|
return NULL;
|
|
}
|
|
const EthernetHdr *ethh = PacketGetEthernet(p);
|
|
if (((uint8_t *)ethh + (ptrdiff_t)ETHERNET_HEADER_LEN) >
|
|
((uint8_t *)GET_PKT_DATA(p) + (ptrdiff_t)GET_PKT_LEN(p))) {
|
|
SCLogDebug("data out of range: %p > %p",
|
|
((uint8_t *)ethh + (ptrdiff_t)ETHERNET_HEADER_LEN),
|
|
((uint8_t *)GET_PKT_DATA(p) + (ptrdiff_t)GET_PKT_LEN(p)));
|
|
return NULL;
|
|
}
|
|
|
|
const uint32_t data_len = (uint32_t)ETHERNET_HEADER_LEN;
|
|
const uint8_t *data = (const uint8_t *)ethh;
|
|
SCLogDebug("inspect data %p / %u", data, data_len);
|
|
|
|
SCInspectionBufferSetupAndApplyTransforms(
|
|
det_ctx, list_id, buffer, data, data_len, transforms);
|
|
}
|
|
|
|
return buffer;
|
|
}
|
|
|
|
#ifdef UNITTESTS
|
|
#include "tests/detect-etherhdr.c"
|
|
#endif
|