dhcp: adds renewal-time keyword

Ticket: #5507
pull/7839/head
Philippe Antoine 3 years ago committed by Victor Julien
parent dc59389087
commit 5ef259722b

@ -10,7 +10,7 @@ Syntax::
dhcp.leasetime:[op]<number>
The version can be matched exactly, or compared using the _op_ setting::
The time can be matched exactly, or compared using the _op_ setting::
dhcp.leasetime:3 # exactly 3
dhcp.leasetime:<3 # smaller than 3
@ -29,7 +29,7 @@ Syntax::
dhcp.rebinding_time:[op]<number>
The version can be matched exactly, or compared using the _op_ setting::
The time can be matched exactly, or compared using the _op_ setting::
dhcp.rebinding_time:3 # exactly 3
dhcp.rebinding_time:<3 # smaller than 3
@ -38,3 +38,22 @@ The version can be matched exactly, or compared using the _op_ setting::
Signature example::
alert dhcp any any -> any any (msg:"small DHCP rebinding time (<3)"; dhcp.rebinding_time:<3; sid:1; rev:1;)
dhcp.renewal_time
-----------------
DHCP renewal time (integer).
Syntax::
dhcp.renewal_time:[op]<number>
The time can be matched exactly, or compared using the _op_ setting::
dhcp.renewal_time:3 # exactly 3
dhcp.renewal_time:<3 # smaller than 3
dhcp.renewal_time:>=2 # greater or equal than 2
Signature example::
alert dhcp any any -> any any (msg:"small DHCP renewal time (<3)"; dhcp.renewal_time:<3; sid:1; rev:1;)

@ -15,7 +15,9 @@
* 02110-1301, USA.
*/
use super::dhcp::{DHCPTransaction, DHCP_OPT_ADDRESS_TIME, DHCP_OPT_REBINDING_TIME};
use super::dhcp::{
DHCPTransaction, DHCP_OPT_ADDRESS_TIME, DHCP_OPT_REBINDING_TIME, DHCP_OPT_RENEWAL_TIME,
};
use super::parser::DHCPOptionWrapper;
#[no_mangle]
@ -47,3 +49,18 @@ pub unsafe extern "C" fn rs_dhcp_tx_get_rebinding_time(
}
return 0;
}
#[no_mangle]
pub unsafe extern "C" fn rs_dhcp_tx_get_renewal_time(
tx: &mut DHCPTransaction, res: *mut u64,
) -> u8 {
for option in &tx.message.options {
if option.code == DHCP_OPT_RENEWAL_TIME {
if let DHCPOptionWrapper::TimeValue(ref time_value) = option.option {
*res = time_value.seconds as u64;
return 1;
}
}
}
return 0;
}

@ -298,6 +298,7 @@ noinst_HEADERS = \
detect-snmp-version.h \
detect-dhcp-leasetime.h \
detect-dhcp-rebinding-time.h \
detect-dhcp-renewal-time.h \
detect-ssh-hassh.h \
detect-ssh-hassh-server.h \
detect-ssh-hassh-server-string.h \
@ -897,6 +898,7 @@ libsuricata_c_a_SOURCES = \
detect-snmp-version.c \
detect-dhcp-leasetime.c \
detect-dhcp-rebinding-time.c \
detect-dhcp-renewal-time.c \
detect-ssh-hassh.c \
detect-ssh-hassh-server.c \
detect-ssh-hassh-server-string.c \

@ -0,0 +1,130 @@
/* Copyright (C) 2022 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.
*/
#include "suricata-common.h"
#include "rust.h"
#include "detect-dhcp-renewal-time.h"
#include "detect-engine.h"
#include "detect-engine-mpm.h"
#include "detect-engine-prefilter.h"
#include "detect-engine-uint.h"
#include "detect-parse.h"
static int g_buffer_id = 0;
/**
* \internal
* \brief Function to match renewal time of a TX
*
* \param t Pointer to thread vars.
* \param det_ctx Pointer to the pattern matcher thread.
* \param f Pointer to the current flow.
* \param flags Flags.
* \param state App layer state.
* \param s Pointer to the Signature.
* \param m Pointer to the sigmatch that we will cast into
* DetectU64Data.
*
* \retval 0 no match.
* \retval 1 match.
*/
static int DetectDHCPRenewalTimeMatch(DetectEngineThreadCtx *det_ctx, Flow *f, uint8_t flags,
void *state, void *txv, const Signature *s, const SigMatchCtx *ctx)
{
SCEnter();
uint64_t res;
if (rs_dhcp_tx_get_renewal_time(txv, &res)) {
const DetectU64Data *dd = (const DetectU64Data *)ctx;
if (DetectU64Match(res, dd)) {
SCReturnInt(1);
}
}
SCReturnInt(0);
}
/**
* \internal
* \brief Function to free memory associated with DetectU64Data.
*
* \param de_ptr Pointer to DetectU64Data.
*/
static void DetectDHCPRenewalTimeFree(DetectEngineCtx *de_ctx, void *ptr)
{
rs_detect_u64_free(ptr);
}
/**
* \brief Function to add the parsed dhcp renewal time field into the current signature.
*
* \param de_ctx Pointer to the Detection Engine Context.
* \param s Pointer to the Current Signature.
* \param rawstr Pointer to the user provided flags options.
* \param type Defines if this is notBefore or notAfter.
*
* \retval 0 on Success.
* \retval -1 on Failure.
*/
static int DetectDHCPRenewalTimeSetup(DetectEngineCtx *de_ctx, Signature *s, const char *rawstr)
{
if (DetectSignatureSetAppProto(s, ALPROTO_DHCP) != 0)
return -1;
DetectU64Data *dd = DetectU64Parse(rawstr);
if (dd == NULL) {
SCLogError(SC_ERR_INVALID_ARGUMENT, "Parsing \'%s\' failed for %s", rawstr,
sigmatch_table[DETECT_AL_DHCP_RENEWAL_TIME].name);
return -1;
}
/* okay so far so good, lets get this into a SigMatch
* and put it in the Signature. */
SigMatch *sm = SigMatchAlloc();
if (sm == NULL)
goto error;
sm->type = DETECT_AL_DHCP_RENEWAL_TIME;
sm->ctx = (void *)dd;
SigMatchAppendSMToList(s, sm, g_buffer_id);
return 0;
error:
DetectDHCPRenewalTimeFree(de_ctx, dd);
return -1;
}
/**
* \brief Registration function for dhcp.procedure keyword.
*/
void DetectDHCPRenewalTimeRegister(void)
{
sigmatch_table[DETECT_AL_DHCP_RENEWAL_TIME].name = "dhcp.renewal_time";
sigmatch_table[DETECT_AL_DHCP_RENEWAL_TIME].desc = "match DHCP renewal time";
sigmatch_table[DETECT_AL_DHCP_RENEWAL_TIME].url = "/rules/dhcp-keywords.html#dhcp-renewal-time";
sigmatch_table[DETECT_AL_DHCP_RENEWAL_TIME].AppLayerTxMatch = DetectDHCPRenewalTimeMatch;
sigmatch_table[DETECT_AL_DHCP_RENEWAL_TIME].Setup = DetectDHCPRenewalTimeSetup;
sigmatch_table[DETECT_AL_DHCP_RENEWAL_TIME].Free = DetectDHCPRenewalTimeFree;
DetectAppLayerInspectEngineRegister2("dhcp.renewal-time", ALPROTO_DHCP, SIG_FLAG_TOSERVER, 0,
DetectEngineInspectGenericList, NULL);
DetectAppLayerInspectEngineRegister2("dhcp.renewal-time", ALPROTO_DHCP, SIG_FLAG_TOCLIENT, 0,
DetectEngineInspectGenericList, NULL);
g_buffer_id = DetectBufferTypeGetByName("dhcp.renewal-time");
}

@ -0,0 +1,23 @@
/* Copyright (C) 2022 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.
*/
#ifndef __DETECT_DHCP_RENEWAL_TIME_H__
#define __DETECT_DHCP_RENEWAL_TIME_H__
void DetectDHCPRenewalTimeRegister(void);
#endif /* __DETECT_DHCP_RENEWAL_TIME_H__ */

@ -203,6 +203,7 @@
#include "detect-template-rust-buffer.h"
#include "detect-dhcp-leasetime.h"
#include "detect-dhcp-rebinding-time.h"
#include "detect-dhcp-renewal-time.h"
#include "detect-snmp-usm.h"
#include "detect-snmp-version.h"
#include "detect-snmp-community.h"
@ -643,6 +644,7 @@ void SigTableSetup(void)
DetectTemplateRustBufferRegister();
DetectDHCPLeaseTimeRegister();
DetectDHCPRebindingTimeRegister();
DetectDHCPRenewalTimeRegister();
DetectSNMPUsmRegister();
DetectSNMPVersionRegister();
DetectSNMPCommunityRegister();

@ -273,6 +273,7 @@ enum DetectKeywordId {
DETECT_AL_TEMPLATE_RUST_BUFFER,
DETECT_AL_DHCP_LEASETIME,
DETECT_AL_DHCP_REBINDING_TIME,
DETECT_AL_DHCP_RENEWAL_TIME,
DETECT_AL_SNMP_USM,
DETECT_AL_SNMP_VERSION,
DETECT_AL_SNMP_COMMUNITY,

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