diff --git a/doc/userguide/rules/dhcp-keywords.rst b/doc/userguide/rules/dhcp-keywords.rst index adac122b29..05b879eb2a 100644 --- a/doc/userguide/rules/dhcp-keywords.rst +++ b/doc/userguide/rules/dhcp-keywords.rst @@ -19,3 +19,22 @@ The version can be matched exactly, or compared using the _op_ setting:: Signature example:: alert dhcp any any -> any any (msg:"small DHCP lease time (<3)"; dhcp.leasetime:<3; sid:1; rev:1;) + +dhcp.rebinding_time +------------------- + +DHCP rebinding time (integer). + +Syntax:: + + dhcp.rebinding_time:[op] + +The version can be matched exactly, or compared using the _op_ setting:: + + dhcp.rebinding_time:3 # exactly 3 + dhcp.rebinding_time:<3 # smaller than 3 + dhcp.rebinding_time:>=2 # greater or equal than 2 + +Signature example:: + + alert dhcp any any -> any any (msg:"small DHCP rebinding time (<3)"; dhcp.rebinding_time:<3; sid:1; rev:1;) diff --git a/rust/src/dhcp/detect.rs b/rust/src/dhcp/detect.rs index c257f94c2c..723df5b99d 100644 --- a/rust/src/dhcp/detect.rs +++ b/rust/src/dhcp/detect.rs @@ -15,7 +15,7 @@ * 02110-1301, USA. */ -use super::dhcp::{DHCPTransaction, DHCP_OPT_ADDRESS_TIME}; +use super::dhcp::{DHCPTransaction, DHCP_OPT_ADDRESS_TIME, DHCP_OPT_REBINDING_TIME}; use super::parser::DHCPOptionWrapper; #[no_mangle] @@ -32,3 +32,18 @@ pub unsafe extern "C" fn rs_dhcp_tx_get_leasetime( } return 0; } + +#[no_mangle] +pub unsafe extern "C" fn rs_dhcp_tx_get_rebinding_time( + tx: &mut DHCPTransaction, res: *mut u64, +) -> u8 { + for option in &tx.message.options { + if option.code == DHCP_OPT_REBINDING_TIME { + if let DHCPOptionWrapper::TimeValue(ref time_value) = option.option { + *res = time_value.seconds as u64; + return 1; + } + } + } + return 0; +} diff --git a/src/Makefile.am b/src/Makefile.am index 36033f31db..3a4ad01d63 100755 --- a/src/Makefile.am +++ b/src/Makefile.am @@ -297,6 +297,7 @@ noinst_HEADERS = \ detect-snmp-usm.h \ detect-snmp-version.h \ detect-dhcp-leasetime.h \ + detect-dhcp-rebinding-time.h \ detect-ssh-hassh.h \ detect-ssh-hassh-server.h \ detect-ssh-hassh-server-string.h \ @@ -895,6 +896,7 @@ libsuricata_c_a_SOURCES = \ detect-snmp-usm.c \ detect-snmp-version.c \ detect-dhcp-leasetime.c \ + detect-dhcp-rebinding-time.c \ detect-ssh-hassh.c \ detect-ssh-hassh-server.c \ detect-ssh-hassh-server-string.c \ diff --git a/src/detect-dhcp-rebinding-time.c b/src/detect-dhcp-rebinding-time.c new file mode 100644 index 0000000000..2a8ce9d84e --- /dev/null +++ b/src/detect-dhcp-rebinding-time.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-rebinding-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 rebinding 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 DetectDHCPRebindingTimeMatch(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_rebinding_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 DetectDHCPRebindingTimeFree(DetectEngineCtx *de_ctx, void *ptr) +{ + rs_detect_u64_free(ptr); +} + +/** + * \brief Function to add the parsed dhcp rebinding 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 DetectDHCPRebindingTimeSetup(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_REBINDING_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_REBINDING_TIME; + sm->ctx = (void *)dd; + + SigMatchAppendSMToList(s, sm, g_buffer_id); + return 0; + +error: + DetectDHCPRebindingTimeFree(de_ctx, dd); + return -1; +} + +/** + * \brief Registration function for dhcp.procedure keyword. + */ +void DetectDHCPRebindingTimeRegister(void) +{ + sigmatch_table[DETECT_AL_DHCP_REBINDING_TIME].name = "dhcp.rebinding_time"; + sigmatch_table[DETECT_AL_DHCP_REBINDING_TIME].desc = "match DHCP rebinding time"; + sigmatch_table[DETECT_AL_DHCP_REBINDING_TIME].url = "/rules/dhcp-keywords.html#dhcp-rebinding-time"; + sigmatch_table[DETECT_AL_DHCP_REBINDING_TIME].AppLayerTxMatch = DetectDHCPRebindingTimeMatch; + sigmatch_table[DETECT_AL_DHCP_REBINDING_TIME].Setup = DetectDHCPRebindingTimeSetup; + sigmatch_table[DETECT_AL_DHCP_REBINDING_TIME].Free = DetectDHCPRebindingTimeFree; + + DetectAppLayerInspectEngineRegister2("dhcp.rebinding-time", ALPROTO_DHCP, SIG_FLAG_TOSERVER, 0, + DetectEngineInspectGenericList, NULL); + + DetectAppLayerInspectEngineRegister2("dhcp.rebinding-time", ALPROTO_DHCP, SIG_FLAG_TOCLIENT, 0, + DetectEngineInspectGenericList, NULL); + + g_buffer_id = DetectBufferTypeGetByName("dhcp.rebinding-time"); +} diff --git a/src/detect-dhcp-rebinding-time.h b/src/detect-dhcp-rebinding-time.h new file mode 100644 index 0000000000..169efad70b --- /dev/null +++ b/src/detect-dhcp-rebinding-time.h @@ -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_REBINDING_TIME_H__ +#define __DETECT_DHCP_REBINDING_TIME_H__ + +void DetectDHCPRebindingTimeRegister(void); + +#endif /* __DETECT_DHCP_REBINDING_TIME_H__ */ diff --git a/src/detect-engine-register.c b/src/detect-engine-register.c index 66e7af8f91..0d1ff9072b 100644 --- a/src/detect-engine-register.c +++ b/src/detect-engine-register.c @@ -202,6 +202,7 @@ #include "detect-target.h" #include "detect-template-rust-buffer.h" #include "detect-dhcp-leasetime.h" +#include "detect-dhcp-rebinding-time.h" #include "detect-snmp-usm.h" #include "detect-snmp-version.h" #include "detect-snmp-community.h" @@ -641,6 +642,7 @@ void SigTableSetup(void) DetectTargetRegister(); DetectTemplateRustBufferRegister(); DetectDHCPLeaseTimeRegister(); + DetectDHCPRebindingTimeRegister(); DetectSNMPUsmRegister(); DetectSNMPVersionRegister(); DetectSNMPCommunityRegister(); diff --git a/src/detect-engine-register.h b/src/detect-engine-register.h index 595e656e28..589b6f27b2 100644 --- a/src/detect-engine-register.h +++ b/src/detect-engine-register.h @@ -272,6 +272,7 @@ enum DetectKeywordId { DETECT_TARGET, DETECT_AL_TEMPLATE_RUST_BUFFER, DETECT_AL_DHCP_LEASETIME, + DETECT_AL_DHCP_REBINDING_TIME, DETECT_AL_SNMP_USM, DETECT_AL_SNMP_VERSION, DETECT_AL_SNMP_COMMUNITY,