Code in charge of protocol decoding. More...

Files
file	decode-chdlc.c

file	decode-erspan.c

file	decode-esp.c

file	decode-ethernet.c

file	decode-gre.c

file	decode-icmpv4.c

file	decode-icmpv6.c

file	decode-ipv4.c

file	decode-ipv6.c

file	decode-nsh.c

file	decode-null.c

file	decode-ppp.c

file	decode-pppoe.c

file	decode-raw.c

file	decode-sctp.c

file	decode-sll.c

file	decode-tcp.c

file	decode-template.c

file	decode-teredo.c

file	decode-udp.c

file	decode-vlan.c

file	decode-vntag.c

file	decode.c

Data Structures
struct	CaptureStats_

Typedefs
typedef struct CaptureStats_	CaptureStats

Functions
PacketAlert *	PacketAlertCreate (void)
	Initialize PacketAlerts with dynamic alerts array size. More...

void	PacketAlertFree (PacketAlert *pa)

void	PacketFree (Packet *p)
	Return a malloced packet. More...

void	PacketDecodeFinalize (ThreadVars tv, DecodeThreadVars dtv, Packet *p)
	Finalize decoding of a packet. More...

void	PacketUpdateEngineEventCounters (ThreadVars tv, DecodeThreadVars dtv, Packet *p)

Packet *	PacketGetFromAlloc (void)
	Get a malloced packet. More...

void	PacketFreeOrRelease (Packet *p)
	Return a packet to where it was allocated. More...

Packet *	PacketGetFromQueueOrAlloc (void)
	Get a packet. We try to get a packet from the packetpool first, but if that is empty we alloc a packet that is free'd again after processing. More...

int	PacketCallocExtPkt (Packet *p, int datalen)

int	PacketCopyDataOffset (Packet p, uint32_t offset, const uint8_t data, uint32_t datalen)
	Copy data to Packet payload at given offset. More...

int	PacketCopyData (Packet p, const uint8_t pktdata, uint32_t pktlen)
	Copy data to Packet payload and set packet length. More...

Packet *	PacketTunnelPktSetup (ThreadVars tv, DecodeThreadVars dtv, Packet parent, const uint8_t pkt, uint32_t len, enum DecodeTunnelProto proto)
	Setup a pseudo packet (tunnel) More...

Packet *	PacketDefragPktSetup (Packet parent, const uint8_t pkt, uint32_t len, uint8_t proto)
	Setup a pseudo packet (reassembled frags) More...

void	PacketDefragPktSetupParent (Packet *parent)
	inform defrag "parent" that a pseudo packet is now associated to it. More...

void	PacketBypassCallback (Packet *p)

void	PacketSwap (Packet *p)
	switch direction of a packet More...

void	DecodeUnregisterCounters (void)

void	DecodeRegisterPerfCounters (DecodeThreadVars dtv, ThreadVars tv)

void	DecodeUpdatePacketCounters (ThreadVars tv, const DecodeThreadVars dtv, const Packet *p)

void	AddressDebugPrint (Address *a)
	Debug print function for printing addresses. More...

DecodeThreadVars *	DecodeThreadVarsAlloc (ThreadVars *tv)
	Alloc and setup DecodeThreadVars. More...

void	DecodeThreadVarsFree (ThreadVars tv, DecodeThreadVars dtv)

int	PacketSetData (Packet p, const uint8_t pktdata, uint32_t pktlen)
	Set data for Packet and set length when zero copy is used. More...

const char *	PktSrcToString (enum PktSrcEnum pkt_src)

const char *	PacketDropReasonToString (enum PacketDropReason r)

void	CaptureStatsUpdate (ThreadVars tv, const Packet p)

void	CaptureStatsSetup (ThreadVars *tv)

void	DecodeGlobalConfig (void)

void	PacketAlertGetMaxConfig (void)

Variables
uint32_t	default_packet_size = 0

bool	stats_decoder_events

const char *	stats_decoder_events_prefix

bool	stats_stream_events

uint8_t	decoder_max_layers = PKT_DEFAULT_MAX_DECODED_LAYERS

uint16_t	packet_alert_max = PACKET_ALERT_MAX

ExceptionPolicyStatsSetts	defrag_memcap_eps_stats

ExceptionPolicyStatsSetts	flow_memcap_eps_stats

thread_local CaptureStats	t_capture_stats

Detailed Description

Code in charge of protocol decoding.

The task of decoding packets is made in different files and as Suricata is supporting encapsulation there is a potential recursivity in the call.

For each protocol a DecodePROTO function is provided. For example we have DecodeIPV4() for IPv4 and DecodePPP() for PPP.

These functions have all a pkt and a len argument which are respectively a pointer to the protocol data and the length of this protocol data.

Attention: The pkt parameter must point to the effective data because it will be used later to set per protocol pointer like Packet::tcph

Typedef Documentation

◆ CaptureStats

typedef struct CaptureStats_ CaptureStats

Function Documentation

◆ AddressDebugPrint()

void AddressDebugPrint ( Address * a )

Debug print function for printing addresses.

Parameters

Address object

Todo:: IPv6

Definition at line 756 of file decode.c.

References Address_::family, PrintInet(), and SCLogDebug.

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◆ CaptureStatsSetup()

void CaptureStatsSetup ( ThreadVars * tv )

Definition at line 983 of file decode.c.

References CaptureStats_::counter_ips_accepted, CaptureStats_::counter_ips_blocked, CaptureStats_::counter_ips_rejected, CaptureStats_::counter_ips_replaced, EngineModeIsIPS(), PKT_DROP_REASON_MAX, PKT_DROP_REASON_NOT_SET, StatsRegisterCounter(), t_capture_stats, and tv.

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◆ CaptureStatsUpdate()

void CaptureStatsUpdate	(	ThreadVars *	tv,
		const Packet *	p
	)

Definition at line 963 of file decode.c.

References ACTION_DROP, ACTION_REJECT_ANY, CaptureStats_::counter_drop_reason, CaptureStats_::counter_ips_accepted, CaptureStats_::counter_ips_blocked, CaptureStats_::counter_ips_rejected, CaptureStats_::counter_ips_replaced, Packet_::drop_reason, EngineModeIsIPS(), Packet_::flags, PacketCheckAction(), PKT_DROP_REASON_NOT_SET, PKT_IS_PSEUDOPKT, PKT_STREAM_MODIFIED, StatsIncr(), t_capture_stats, tv, and unlikely.

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◆ DecodeGlobalConfig()

void DecodeGlobalConfig ( void )

Definition at line 999 of file decode.c.

References ConfGetInt(), DecodeERSPANConfig(), DecodeGeneveConfig(), decoder_max_layers, DecodeTeredoConfig(), DecodeVXLANConfig(), PacketAlertGetMaxConfig(), and SCLogWarning.

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◆ DecodeRegisterPerfCounters()

void DecodeRegisterPerfCounters	(	DecodeThreadVars *	dtv,
		ThreadVars *	tv
	)

Definition at line 602 of file decode.c.

Referenced by DecodeErfDagThreadInit().

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◆ DecodeThreadVarsAlloc()

DecodeThreadVars* DecodeThreadVarsAlloc ( ThreadVars * tv )

Alloc and setup DecodeThreadVars.

Definition at line 773 of file decode.c.

References DecodeThreadVars_::app_tctx, AppLayerGetCtxThread(), DecodeThreadVarsFree(), dtv, DecodeThreadVars_::output_flow_thread_data, OutputFlowLogThreadInit(), SCCalloc, SCLogError, TM_ECODE_OK, and tv.

Referenced by DecodeErfDagThreadInit().

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◆ DecodeThreadVarsFree()

void DecodeThreadVarsFree	(	ThreadVars *	tv,
		DecodeThreadVars *	dtv
	)

Definition at line 791 of file decode.c.

References DecodeThreadVars_::app_tctx, AppLayerDestroyCtxThread(), dtv, DecodeThreadVars_::output_flow_thread_data, OutputFlowLogThreadDeinit(), SCFree, and tv.

Referenced by DecodeErfDagThreadDeinit(), and DecodeThreadVarsAlloc().

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◆ DecodeUnregisterCounters()

void DecodeUnregisterCounters ( void )

Definition at line 576 of file decode.c.

References SCMutexLock.

◆ DecodeUpdatePacketCounters()

void DecodeUpdatePacketCounters	(	ThreadVars *	tv,
		const DecodeThreadVars *	dtv,
		const Packet *	p
	)

Definition at line 739 of file decode.c.

References DecodeThreadVars_::counter_avg_pkt_size, DecodeThreadVars_::counter_bytes, DecodeThreadVars_::counter_max_pkt_size, DecodeThreadVars_::counter_pkts, dtv, GET_PKT_LEN, StatsAddUI64(), StatsIncr(), StatsSetUI64(), and tv.

Referenced by DecodeErfDag().

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◆ PacketAlertCreate()

PacketAlert* PacketAlertCreate ( void )

Initialize PacketAlerts with dynamic alerts array size.

Definition at line 140 of file decode.c.

References BUG_ON, packet_alert_max, and SCCalloc.

Referenced by PacketInit().

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◆ PacketAlertFree()

void PacketAlertFree ( PacketAlert * pa )

Definition at line 148 of file decode.c.

References SCFree.

Referenced by PacketDestructor().

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◆ PacketAlertGetMaxConfig()

void PacketAlertGetMaxConfig ( void )

Definition at line 1016 of file decode.c.

References ConfGetInt(), packet_alert_max, SCLogDebug, and SCLogWarning.

Referenced by DecodeGlobalConfig().

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◆ PacketBypassCallback()

void PacketBypassCallback ( Packet * p )

Note: if p->flow is set, the flow is locked

Definition at line 504 of file decode.c.

References Packet_::BypassPacketsFlow, Packet_::flow, Flow_::flow_state, FLOW_STATE_LOCAL_BYPASSED, FlowGetStorageById(), FlowSetStorageById(), FlowUpdateState(), GetFlowBypassInfoID(), PKT_IS_PSEUDOPKT, and SCCalloc.

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◆ PacketCallocExtPkt()

int PacketCallocExtPkt	(	Packet *	p,
		int	datalen
	)

inline

Definition at line 283 of file decode.c.

References Packet_::ext_pkt, SCCalloc, SET_PKT_LEN, and unlikely.

◆ PacketCopyData()

int PacketCopyData	(	Packet *	p,
		const uint8_t *	pktdata,
		uint32_t	pktlen
	)

inline

Copy data to Packet payload and set packet length.

Parameters

Pointer	to the Packet to modify
Pointer	to the data to copy
Length	of the data to copy

Definition at line 351 of file decode.c.

References PacketCopyDataOffset(), and SET_PKT_LEN.

Referenced by PacketDefragPktSetup(), and PacketTunnelPktSetup().

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◆ PacketCopyDataOffset()

int PacketCopyDataOffset	(	Packet *	p,
		uint32_t	offset,
		const uint8_t *	data,
		uint32_t	datalen
	)

inline

Copy data to Packet payload at given offset.

This function copies data/payload to a Packet. It uses the space allocated at Packet creation (pointed by Packet::pkt) or allocate some memory (pointed by Packet::ext_pkt) if the data size is to big to fit in initial space (of size default_packet_size).

Parameters

Pointer	to the Packet to modify
Offset	of the copy relatively to payload of Packet
Pointer	to the data to copy
Length	of the data to copy

Definition at line 309 of file decode.c.

References default_packet_size, Packet_::ext_pkt, GET_PKT_DIRECT_DATA, GET_PKT_DIRECT_MAX_SIZE, MAX_PAYLOAD_SIZE, offset, SCMalloc, SET_PKT_LEN, and unlikely.

Referenced by PacketCopyData().

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◆ PacketDecodeFinalize()

void PacketDecodeFinalize	(	ThreadVars *	tv,
		DecodeThreadVars *	dtv,
		Packet *	p
	)

Finalize decoding of a packet.

This function needs to be call at the end of decode functions when decoding has been successful.

Definition at line 206 of file decode.c.

References DecodeThreadVars_::counter_invalid, dtv, Packet_::flags, PKT_IS_INVALID, StatsIncr(), and tv.

Referenced by DecodeErfDag().

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◆ PacketDefragPktSetup()

Packet* PacketDefragPktSetup	(	Packet *	parent,
		const uint8_t *	pkt,
		uint32_t	len,
		uint8_t	proto
	)

Setup a pseudo packet (reassembled frags)

Difference with PacketPseudoPktSetup is that this func doesn't increment the recursion level. It needs to be on the same level as the frags because we run the flow engine against this and we need to get the same flow.

Parameters

parent	parent packet for this pseudo pkt
pkt	raw packet data
len	packet data length
proto	protocol of the tunneled packet

Return values

p	the pseudo packet or NULL if out of memory

Definition at line 447 of file decode.c.

References BUG_ON, len, Packet_::livedev, PacketCopyData(), PacketGetFromQueueOrAlloc(), PacketTunnelChild, Packet_::recursion_level, Packet_::root, SCEnter, SCReturnPtr, Packet_::tenant_id, Packet_::ts, Packet_::ttype, unlikely, Packet_::vlan_id, and Packet_::vlan_idx.

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◆ PacketDefragPktSetupParent()

void PacketDefragPktSetupParent ( Packet * parent )

inform defrag "parent" that a pseudo packet is now associated to it.

Definition at line 486 of file decode.c.

References PacketTunnelNone, PacketTunnelRoot, and Packet_::ttype.

◆ PacketDropReasonToString()

const char* PacketDropReasonToString ( enum PacketDropReason r )

Definition at line 872 of file decode.c.

References PKT_DROP_REASON_APPLAYER_ERROR, PKT_DROP_REASON_APPLAYER_MEMCAP, PKT_DROP_REASON_DECODE_ERROR, PKT_DROP_REASON_DEFRAG_ERROR, PKT_DROP_REASON_DEFRAG_MEMCAP, PKT_DROP_REASON_FLOW_DROP, PKT_DROP_REASON_FLOW_MEMCAP, PKT_DROP_REASON_INNER_PACKET, PKT_DROP_REASON_MAX, PKT_DROP_REASON_NFQ_ERROR, PKT_DROP_REASON_NOT_SET, PKT_DROP_REASON_RULES, PKT_DROP_REASON_RULES_THRESHOLD, PKT_DROP_REASON_STREAM_ERROR, PKT_DROP_REASON_STREAM_MEMCAP, PKT_DROP_REASON_STREAM_MIDSTREAM, and PKT_DROP_REASON_STREAM_REASSEMBLY.

◆ PacketFree()

void PacketFree ( Packet * p )

Return a malloced packet.

Definition at line 193 of file decode.c.

References PacketDestructor(), and SCFree.

Referenced by PacketFreeOrRelease(), PacketGetFromAlloc(), and UTHFreePacket().

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◆ PacketFreeOrRelease()

void PacketFreeOrRelease ( Packet * p )

Return a packet to where it was allocated.

Definition at line 250 of file decode.c.

References likely, PacketFree(), PacketPoolReturnPacket(), Packet_::pool, and Packet_::ReleasePacket.

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◆ PacketGetFromAlloc()

Packet* PacketGetFromAlloc ( void )

Get a malloced packet.

Return values

p	packet, NULL on error

Definition at line 232 of file decode.c.

References PACKET_PROFILING_START, PacketFree(), PacketInit(), Packet_::ReleasePacket, SCCalloc, SCLogDebug, SIZE_OF_PACKET, and unlikely.

Referenced by PacketGetFromQueueOrAlloc(), UTHBuildPacketFromEth(), UTHBuildPacketIPV6Real(), and UTHBuildPacketReal().

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◆ PacketGetFromQueueOrAlloc()

Packet* PacketGetFromQueueOrAlloc ( void )

Get a packet. We try to get a packet from the packetpool first, but if that is empty we alloc a packet that is free'd again after processing.

Return values

p	packet, NULL on error

Definition at line 267 of file decode.c.

References DEBUG_VALIDATE_BUG_ON, PACKET_PROFILING_START, PacketGetFromAlloc(), PacketPoolGetPacket(), PacketPoolReturnPacket(), and Packet_::ReleasePacket.

Referenced by PacketDefragPktSetup(), PacketTunnelPktSetup(), and ReceiveErfFileLoop().

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◆ PacketSetData()

int PacketSetData	(	Packet *	p,
		const uint8_t *	pktdata,
		uint32_t	pktlen
	)

inline

Set data for Packet and set length when zero copy is used.

Parameters

Pointer	to the Packet to modify
Pointer	to the data
Length	of the data

Definition at line 811 of file decode.c.

References Packet_::ext_pkt, Packet_::flags, PKT_ZERO_COPY, SET_PKT_LEN, and unlikely.

◆ PacketSwap()

void PacketSwap ( Packet * p )

switch direction of a packet

Definition at line 551 of file decode.c.

References FLOW_PKT_TOCLIENT, FLOW_PKT_TOCLIENT_FIRST, FLOW_PKT_TOSERVER, FLOW_PKT_TOSERVER_FIRST, Packet_::flowflags, and PKT_IS_TOSERVER.

◆ PacketTunnelPktSetup()

Packet* PacketTunnelPktSetup	(	ThreadVars *	tv,
		DecodeThreadVars *	dtv,
		Packet *	parent,
		const uint8_t *	pkt,
		uint32_t	len,
		enum DecodeTunnelProto	proto
	)

Setup a pseudo packet (tunnel)

Parameters

parent	parent packet for this pseudo pkt
pkt	raw packet data
len	packet data length
proto	protocol of the tunneled packet

Return values

p	the pseudo packet or NULL if out of memory

Definition at line 367 of file decode.c.

References BUG_ON, Packet_::datalink, DEBUG_VALIDATE_BUG_ON, decoder_max_layers, DLT_RAW, ENGINE_SET_INVALID_EVENT, GENERIC_TOO_MANY_LAYERS, len, Packet_::livedev, Packet_::nb_decoded_layers, PacketCopyData(), PacketGetFromQueueOrAlloc(), PacketTunnelChild, PacketTunnelRoot, Packet_::recursion_level, Packet_::root, SCEnter, SCReturnPtr, Packet_::tenant_id, Packet_::ts, Packet_::ttype, and unlikely.

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◆ PacketUpdateEngineEventCounters()

void PacketUpdateEngineEventCounters	(	ThreadVars *	tv,
		DecodeThreadVars *	dtv,
		Packet *	p
	)

Definition at line 213 of file decode.c.

References PacketEngineEvents_::cnt, DecodeThreadVars_::counter_engine_events, DECODE_EVENT_PACKET_MAX, dtv, PacketEngineEvents_::events, Packet_::events, stats_decoder_events, stats_stream_events, StatsIncr(), and tv.

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◆ PktSrcToString()

const char* PktSrcToString ( enum PktSrcEnum pkt_src )

Definition at line 824 of file decode.c.

References DEBUG_VALIDATE_BUG_ON, PKT_SRC_CAPTURE_TIMEOUT, PKT_SRC_DECODER_GENEVE, PKT_SRC_DECODER_GRE, PKT_SRC_DECODER_IPV4, PKT_SRC_DECODER_IPV6, PKT_SRC_DECODER_TEREDO, PKT_SRC_DECODER_VXLAN, PKT_SRC_DEFRAG, PKT_SRC_DETECT_RELOAD_FLUSH, PKT_SRC_FFR, PKT_SRC_SHUTDOWN_FLUSH, PKT_SRC_STREAM_TCP_DETECTLOG_FLUSH, and PKT_SRC_WIRE.

Referenced by StreamTcp().

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Variable Documentation

◆ decoder_max_layers

uint8_t decoder_max_layers = PKT_DEFAULT_MAX_DECODED_LAYERS

Definition at line 81 of file decode.c.

Referenced by DecodeGlobalConfig(), and PacketTunnelPktSetup().

◆ default_packet_size

uint32_t default_packet_size = 0

Definition at line 77 of file decode.c.

Referenced by PacketCopyDataOffset(), and RunUnittests().

◆ defrag_memcap_eps_stats

ExceptionPolicyStatsSetts defrag_memcap_eps_stats

Initial value:

= {
    .valid_settings_ids = {
          false,
             false,
      true,
        false,
      true,
      false,
        false,
           true,
    },
    .valid_settings_ips = {
          false,
             false,
      true,
        false,
      true,
      true,
        false,
           true,
    },
}

Definition at line 86 of file decode.c.

◆ flow_memcap_eps_stats

ExceptionPolicyStatsSetts flow_memcap_eps_stats

Initial value:

= {
    .valid_settings_ids = {
          false,
             false,
      true,
        false,
      true,
      false,
        false,
           true,
    },
    .valid_settings_ips = {
          false,
             false,
      true,
        false,
      true,
      true,
        false,
           true,
    },
}

Definition at line 112 of file decode.c.

Referenced by DecodeRegisterPerfCounters().

◆ packet_alert_max

uint16_t packet_alert_max = PACKET_ALERT_MAX

Definition at line 82 of file decode.c.

Referenced by AlertQueueInit(), PacketAlertCreate(), and PacketAlertGetMaxConfig().

◆ stats_decoder_events

bool stats_decoder_events

Definition at line 101 of file counters.c.

Referenced by PacketUpdateEngineEventCounters().

◆ stats_decoder_events_prefix

const char* stats_decoder_events_prefix

add stream events as stats? disabled by default

Definition at line 102 of file counters.c.

◆ stats_stream_events

bool stats_stream_events

Definition at line 104 of file counters.c.

Referenced by PacketUpdateEngineEventCounters().

◆ t_capture_stats

thread_local CaptureStats t_capture_stats

Definition at line 961 of file decode.c.

Referenced by CaptureStatsSetup(), and CaptureStatsUpdate().

Files

Data Structures

Typedefs

Functions

Variables

Detailed Description

Typedef Documentation

◆ CaptureStats

Function Documentation

◆ AddressDebugPrint()

◆ CaptureStatsSetup()

◆ CaptureStatsUpdate()

◆ DecodeGlobalConfig()

◆ DecodeRegisterPerfCounters()

◆ DecodeThreadVarsAlloc()

◆ DecodeThreadVarsFree()

◆ DecodeUnregisterCounters()

◆ DecodeUpdatePacketCounters()

◆ PacketAlertCreate()

◆ PacketAlertFree()

◆ PacketAlertGetMaxConfig()

◆ PacketBypassCallback()

◆ PacketCallocExtPkt()

◆ PacketCopyData()

◆ PacketCopyDataOffset()

◆ PacketDecodeFinalize()

◆ PacketDefragPktSetup()

◆ PacketDefragPktSetupParent()

◆ PacketDropReasonToString()

◆ PacketFree()

◆ PacketFreeOrRelease()

◆ PacketGetFromAlloc()

◆ PacketGetFromQueueOrAlloc()

◆ PacketSetData()

◆ PacketSwap()

◆ PacketTunnelPktSetup()

◆ PacketUpdateEngineEventCounters()

◆ PktSrcToString()

Variable Documentation

◆ decoder_max_layers

◆ default_packet_size

◆ defrag_memcap_eps_stats

◆ flow_memcap_eps_stats

◆ packet_alert_max

◆ stats_decoder_events

◆ stats_decoder_events_prefix

◆ stats_stream_events

◆ t_capture_stats