FM / network

/usr/share/systemtap/examples/network

Name	Size	Mode	Actions
autofs4.meta	397	0644	edit dl rm
autofs4.stp	4167	0755	edit dl rm
connect_stat.meta	404	0644	edit dl rm
connect_stat.stp	1019	0755	edit dl rm
dropwatch.meta	494	0644	edit dl rm
dropwatch.stp	900	0755	edit dl rm
netdev.meta	389	0644	edit dl rm
netdev.stp	1458	0755	edit dl rm
netfilter_drop.meta	630	0644	edit dl rm
netfilter_drop.stp	1156	0755	edit dl rm
netfilter_summary.meta	587	0644	edit dl rm
netfilter_summary.stp	591	0755	edit dl rm
netfilter_summary.txt	2873	0644	edit dl rm
netfilter_summary_json.meta	511	0644	edit dl rm
netfilter_summary_json.stp	1070	0644	edit dl rm
nettop.meta	519	0644	edit dl rm
nettop.stp	989	0755	edit dl rm
nettop.txt	953	0644	edit dl rm
net_xmit_json.meta	453	0644	edit dl rm
net_xmit_json.stp	1801	0644	edit dl rm
nfsd-recent.meta	423	0644	edit dl rm
nfsd-recent.stp	442	0755	edit dl rm
nfsd-trace.meta	314	0644	edit dl rm
nfsd-trace.stp	701	0644	edit dl rm
nfsd-trace.txt	876	0644	edit dl rm
nfsdtop.meta	405	0644	edit dl rm
nfsdtop.stp	3385	0755	edit dl rm
nfsd_unlink.meta	479	0644	edit dl rm
nfsd_unlink.stp	523	0755	edit dl rm
packet_contents.meta	550	0644	edit dl rm
packet_contents.stp	216	0755	edit dl rm
packet_contents.txt	2066	0644	edit dl rm
sk_stream_wait_memory.meta	742	0644	edit dl rm
sk_stream_wait_memory.stp	999	0755	edit dl rm
socket-trace.meta	702	0644	edit dl rm
socket-trace.stp	222	0755	edit dl rm
socktop	9144	0755	edit dl rm
socktop.meta	548	0644	edit dl rm
socktop.txt	4135	0644	edit dl rm
stp_dump.meta	339	0644	edit dl rm
stp_dump.stp	568	0644	edit dl rm
stp_dump.txt	1632	0644	edit dl rm
tcpdumplike.meta	381	0644	edit dl rm
tcpdumplike.stp	581	0755	edit dl rm
tcpipstat.meta	725	0644	edit dl rm
tcpipstat.stp	18247	0755	edit dl rm
tcpipstat.txt	898	0644	edit dl rm
tcp_connections.meta	625	0644	edit dl rm
tcp_connections.stp	361	0755	edit dl rm
tcp_init_cwnd.meta	589	0644	edit dl rm
tcp_init_cwnd.stp	343	0755	edit dl rm
tcp_retransmission.meta	286	0644	edit dl rm
tcp_retransmission.stp	1182	0644	edit dl rm
tcp_trace.meta	684	0644	edit dl rm
tcp_trace.stp	19095	0755	edit dl rm
tcp_trace.txt	3465	0644	edit dl rm
who_sent_it.meta	583	0644	edit dl rm
who_sent_it.stp	477	0644	edit dl rm
who_sent_it.txt	803	0644	edit dl rm

Edit: /usr/share/systemtap/examples/network/tcp_trace.stp (19095B)

#!/usr/bin/stap
/*
 *	Copyright (C) 2009 IBM Corp.
 *	Copyright (C) 2015 Red Hat, Inc.
 *
 *	This file is part of systemtap, and is free software.  You can
 *	redistribute it and/or modify it under the terms of the GNU General
 *	Public License (GPL); either version 2, or (at your option) any
 *	later version.
 *
 *	Version 0.1     wilder@us.ibm.com	2009-05-13
 *	Version 0.3     varuncha@in.ibm.com	2009-05-20
 *	Version 1.0	wilder@us.ibm.com	2009-09-24
 *	Version 1.1	wilder@us.ibm.com	2009-10-08
 *
 *	Tcp connection tracing utility.
 *
 *	Description:
 *	This script traces tcp connections and displays connection parameters.
 *	The filter option specifies what parameters are to be displayed. Address
 *	"rules" must be supplied to limit what connections are to be traced.
 *
 *	Synopsis:
 *	tcp_trace.stp	[filter=all|state|txq|rxq|srtt|snd_cwnd|snd_wnd|rexmit\
 *			|pmtu|ssthresh|timer|rcvwnd|length]\
 *			[timeout=<N sec>]\
 *			[update=change|all]\
 *
 *	Rule format:
 *	  <local ip-address>:<local-port>-<remote ip-address>:<remote-port>
 *
 *	filter  tcp_trace collects the socket state and other connection
 *		parameters from various probe points in the tcp stack; however,
 *		not all this data may needed when debugging a tcp problem.
 *		Specifying only the required parameters reduces analysis time.
 *		Multiple parameters can be specified by using
 *		','.
 *
 *	timeout (optional) When a timeout value (in seconds) is specified
 *		tcp_trace will automatically terminate it's run at the end of
 *		the specified time.  By default the script will run until the
 *		user terminates it by typing a ^c.
 *
 *	update  (optional) By default the script only displays data if there
 *		is a value change in a parameters specified in the "filter".
 *		This can be changed by specifying "update=all", which will
 *		output parameters of every packet that hits the probe.
 *		Note: Changes to the packet length will not trigger an update.
 *
 *	Rules	Rules limit what connections will be traced. Multiple rules may
 *		be given separated by a space. A wild-card value can be used
 *		for any component of the filter. Rules can be used to limit
 *		tracing to a single socket or allow many sockets to be traced.
 *		Memory consumed by the tracer will increase with the number
 *		of connections being traced.
 *
 *		The Rule Format is:
 *		<local-address>:<local-port>-<remote address>:<remote-port>
 *
 *		-Address are specified as ipv4 dot notation address.
 *		-Ports are specified as decimal numbers.
 *
 *		"*" character can be used in any field to indicate a wild-card
 *		value.
 *
 *		Note: The number of active sockets that can be traced is
 *		limited by MAXMAPENTRIES.
 *
 *	Examples:
 *		Here are some examples of using tcp_trace:
 *
 *		Trace TCP connection from 172.16.15.160 to 172.16.15.1 on
 *		port 22 with state,txq,rxq,pmtu filter.
 *
 *		tcp_trace.stp filter=state,txq,rxq,pmtu timeout=100\
 *					172.16.15.160:*-172.16.15.1:22
 *
 *		Trace TCP connection from any address to the local http server.
 *		all parameters are displayed for every packet.
 *
 *		tcp_trace.stp filter=all update=all *.*.*.*:*-*.*.*.*:80
 */

global tcp_state;
global timer_info;

global filter;
global key_list;
global lastkey;
global number_of_rules;

global timeout = -1;
global always_update;

global snd_cwnd_flg;
global snd_cwnd;

global snd_wnd_flg;
global snd_wnd;

global srtt_flg;
global srtt;

global state_flg;
global state;

global txq_flg;
global txq;

global rxq_flg;
global rxq;

global rexmit_flg;
global rexmit;

global pmtu_flg;
global pmtu;

global ssthresh_flg;
global ssthresh;

global timer_flg;
global tx_timer;
global find_timer;

global rcvwnd_flg;
global rcvwnd;

global length_flg;
global length;

probe begin
{
	number_of_rules = process_cmdline()

if ( number_of_rules < 1)
		usage("One or more connection rules must be specified!")
	if ( number_of_rules < 0 )
		usage("Incorrect connection rule format!")

init_tcp_state()
	init_timer_info()

printf("Start TCP Probing.....\n\n");
	print_header();
}

function init_tcp_state ()
{
	tcp_state[1] = "ESTABLISHED"
	tcp_state[2] = "SYN_SENT"
	tcp_state[3] = "SYN_RECV"
	tcp_state[4] = "FIN_WAIT1"
	tcp_state[5] = "FIN_WAIT2"
	tcp_state[6] = "TIME_WAIT"
	tcp_state[7] = "CLOSE"
	tcp_state[8] = "CLOSE_WAIT"
	tcp_state[9] = "LAST_ACK"
	tcp_state[10] = "LISTEN"
	tcp_state[11] = "CLOSING"
}

function state_num2str:string ( state:long )
{
	return (state in tcp_state ? tcp_state[state] : "UNDEF")
}

function init_timer_info ()
{
	timer_info[0] = ""
	timer_info[1] = "Rxmit"
	timer_info[2] = "Delack"
	timer_info[3] = "Probe"
	timer_info[4] = "Keepalv"
}

function timer_info_num2str:string ( timer:long )
{
	return (timer in timer_info ? timer_info[timer] : "UNDEF")
}

probe kernel.{function("tcp_rcv_established"),
              function("tcp_rcv_state_process")}
{
	sk = $sk
	key = filter_key(sk)
	if ( !key ) next;

if ( is_packet_updated(key,sk) ) {
		length[key] = $skb->len;
		print_packet_info(key, 0)
	}
}

probe kernel.function("tcp_transmit_skb")
{
	sk = $sk
	key = filter_key(sk)
	if ( !key ) next;

if ( is_packet_updated(key,sk) ) {
		length[key] = $skb->len;
		print_packet_info(key, 1)
	}
}

probe kernel.function("tcp_keepalive_timer")
{
	if ( !timer_flg ) next;

sk = @choose_defined($data,
			     & @container_of($t, "struct sock", sk_timer))
	key = filter_key(sk)
	if ( !key ) next;

is_packet_updated(key,sk)
	length[key] = 0
	tx_timer[key] = 4;
	print_packet_info(key, 1)
	tx_timer[key] = 0;
}

probe kernel.function("tcp_delack_timer")
{
	if ( !timer_flg ) next;

sk = @choose_defined($data,
			     & @container_of($t, "struct inet_connection_sock", icsk_delack_timer)->icsk_inet->sk)
	key = filter_key(sk)
	if ( !key ) next;

is_packet_updated(key,sk)
	length[key] = 0
	tx_timer[key] = 2;
	print_packet_info(key, 1)
	tx_timer[key] = 0;
}

probe kernel.function("tcp_send_probe0")
{
	if ( !timer_flg ) next;

sk = $sk
	key = filter_key(sk)
	if ( !key ) next;

if ( find_timer[key] == 3 ) {
		find_timer[key] = 0
		tx_timer[key] = 3;
		is_packet_updated(key,sk)
		length[key] = 0
		print_packet_info(key, 1)
		tx_timer[key] = 0;
	}
}

probe kernel.function("tcp_retransmit_skb")
{
	if ( !timer_flg ) next;

sk = $sk;
	key = filter_key(sk)
	if ( !key ) next;

if ( find_timer[key] == 1 ) {
		find_timer[key] = 0
		tx_timer[key] = 1;
		is_packet_updated(key,sk)
		length[key] = $skb->len
		print_packet_info(key,1)
		tx_timer[key] = 0;
	}
}

probe kernel.function("tcp_write_timer")
{
	if ( !timer_flg ) next;

sk = @choose_defined($data,
			     & @container_of($t, "struct inet_connection_sock", icsk_retransmit_timer)->icsk_inet->sk )
	key = filter_key(sk)
	if ( !key ) next;

/* Don't trace calls to tcp_retransmit_skb()
	 * or tcp_send_probe0 that were not the result of a
	 * write timer expiration.
	 */
	find_timer[key] = @cast(sk, "inet_connection_sock")->icsk_pending
}

%( kernel_v > "2.6.24" %?
probe kernel.function("tcp_set_state")
{
	sk = $sk
	new_state = $state
	TCP_CLOSE = 7
	TCP_CLOSE_WAIT = 8
	key = filter_key(sk)
	if ( key && ((new_state == TCP_CLOSE)||(new_state == TCP_CLOSE_WAIT))){
		if (state_flg && state[key]) print_close(key,new_state);
		clean_up(key);
	}
}
%)

function print_header()
{
	printf("%-22s","Source Address")
	printf("%-22s","Dest Address")
	if (state_flg) printf("%-12s","State")
	if (timer_flg) printf("%-8s","Timer")
	if (txq_flg) printf("%8s","Tx-Q")
	if (rxq_flg) printf("%8s","Rx-Q")
	if (pmtu_flg) printf("%8s","PMTU")
	if (snd_cwnd_flg) printf("%8s","SndCwnd")
	if (snd_wnd_flg) printf("%8s","SndWnd")
	if (rcvwnd_flg) printf("%8s","RcvWnd")
	if (srtt_flg) printf("%8s","SSRT")
	if (ssthresh_flg) printf("%14s","Ssthreshold")
	if (rexmit_flg) printf("%8s","Rexmit")
	if (length_flg) printf("%8s","Length")
	printf("\n");
}

function print_packet_info:long ( key:long, SourceIsLocal:long)
{
	foreach ( [laddr, raddr, lport, rport] in key_list ){
			if ( key_list[laddr, raddr, lport, rport] == key )
				break
	}

local_addr = sprintf("%s:%d",ip_ntop(htonl(laddr)), lport)
	remote_addr = sprintf("%s:%d",ip_ntop(htonl(raddr)) ,rport)

SourceIsLocal ? printf("%-22s%-22s",local_addr,remote_addr):
			printf("%-22s%-22s",remote_addr,local_addr)

if (state_flg) printf("%-12s",state_num2str(state[key]))
	if (timer_flg) printf("%-8s",timer_info_num2str(tx_timer[key]))
	if (txq_flg) printf("%8d",txq[key])
	if (rxq_flg) printf("%8d",rxq[key])
	if (pmtu_flg) printf("%8d",pmtu[key])
	if (snd_cwnd_flg) printf("%8d",snd_cwnd[key])
	if (snd_wnd_flg) printf("%8d",snd_wnd[key])
	if (rcvwnd_flg) printf("%8d",rcvwnd[key])
	if (srtt_flg) printf("%8d",srtt[key])
	if (ssthresh_flg) printf("%14d",ssthresh[key])
	if (rexmit_flg) printf("%8d",rexmit[key])
	if (length_flg && length[key]) printf("%8d", length[key])
	printf("\n");
}

%( kernel_v > "2.6.24" %?
function print_close:long (key:long, new_state:long)
{
	foreach ( [laddr, raddr, lport, rport] in key_list ){
			if ( key_list[laddr, raddr, lport, rport] == key )
				break
	}

local_addr = sprintf("%s:%d",ip_ntop(htonl(laddr)), lport)
	remote_addr = sprintf("%s:%d",ip_ntop(htonl(raddr)) ,rport)

printf("%-22s%-22s",local_addr,remote_addr)
	printf("%-12s",state_num2str(new_state))
	printf("\n");
}
%)

/*
 * Update the values in the data collection arrays, returns 1 if one or more
 * values have changed.
 */
function is_packet_updated:long ( key:long, sk:long )
{
	packet_updated = 0

if ( !key ) return 0

if ( state_flg ) {
		new_state = @cast(sk, "sock_common")->skc_state
		if( always_update || (state[key] != new_state) ){
			state[key]= new_state
			packet_updated = 1
		}
	}

if ( txq_flg ) {
		if(@cast(sk, "sock_common")->skc_state == 10)
			new_txq = @cast(sk, "sock")->sk_max_ack_backlog
                else
			new_txq = @cast(sk, "tcp_sock")->write_seq -
					@cast(sk, "tcp_sock")->snd_una
		if( always_update || (txq[key] != new_txq) ){
			txq[key] = new_txq
			packet_updated = 1
		}
	}

if ( rxq_flg ) {
		if(@cast(sk, "sock_common")->skc_state == 10)
			new_rxq = @cast(sk, "sock")->sk_ack_backlog
		else
			new_rxq = @cast(sk, "tcp_sock")->rcv_nxt -
					@cast(sk, "tcp_sock")->copied_seq

if( always_update || (rxq[key] != new_rxq) ){
			rxq[key] = new_rxq
			packet_updated = 1
		}
	}

if( rexmit_flg ) {
		new_rexmit = @cast(sk, "inet_connection_sock")->icsk_retransmits
		if( always_update || (rexmit[key] != new_rexmit ) ){
			rexmit[key] = new_rexmit
			packet_updated = 1
		}
	}

if ( pmtu_flg ) {
		new_pmtu = @cast(sk, "inet_connection_sock")->icsk_pmtu_cookie
		if( always_update || (pmtu[key] != new_pmtu) ){
			pmtu[key] = new_pmtu
			packet_updated = 1
		}
	}

if ( snd_cwnd_flg ) {
		new_snd_cwnd = @cast(sk, "tcp_sock")->snd_cwnd
		if( always_update || (snd_cwnd[key] != new_snd_cwnd) ){
			snd_cwnd[key] = new_snd_cwnd
			packet_updated = 1
		}
	}

if ( snd_wnd_flg ) {
		new_snd_wnd = @cast(sk, "tcp_sock")->snd_wnd
		if( always_update || (snd_wnd[key] != new_snd_wnd) ){
			snd_wnd[key] = new_snd_wnd
			packet_updated = 1
		}
	}

if ( srtt_flg ) {
		new_srtt = @choose_defined(@cast(sk, "tcp_sock")->srtt_us,
					   @cast(sk, "tcp_sock")->srtt)
		if( always_update || (srtt[key] != new_srtt) ){
			srtt[key] = new_srtt
			packet_updated = 1
		}
	}

if( ssthresh_flg ) {
		new_ssthresh = tcp_current_ssthresh(sk)
		if( always_update || (ssthresh[key] != new_ssthresh) ){
			ssthresh[key] = new_ssthresh
			packet_updated = 1
		}
	}

if ( rcvwnd_flg ) {
		new_rcvwnd = @cast(sk, "tcp_sock")->rcv_wnd
		if( always_update || (rcvwnd[key] != new_rcvwnd) ){
			rcvwnd[key] = new_rcvwnd
			packet_updated = 1
		}
	}

return packet_updated
}

/*
 * copied from:
 * include/net/tcp.h:tcp_current_ssthresh()
 */
function tcp_current_ssthresh(sk:long)
{
	if ((1 << @cast(sk, "inet_connection_sock")->icsk_ca_state) &
						((1 << 2) | (1 << 3))){
		return @cast(sk, "tcp_sock")->snd_ssthresh
	}else{
		return netmax(@cast(sk, "tcp_sock")->snd_ssthresh,
				((@cast(sk, "tcp_sock")->snd_cwnd >>1)+
				(@cast(sk, "tcp_sock")->snd_cwnd >> 2)))
	}
}

function netmax:long (val1:long, val2:long)
{
	if(val1 > val2)
		return val1
	else
		return val2
}

/* All command line arguments other than the address rules are processed
 * first and must be placed on the command line prior to any address rules.
 */
function process_cmdline:long ()
{
        filter_number = 0
        for (i=1; i <= argc; i++) {
                argument = tokenize(argv[i], "=")

if (argument == "help")
			usage("")

if (argument == "filter") {
			filter_given=1;
                        argv[i]=""
                        while(strlen(byte = tokenize(argv[i], ",")) != 0) {
                                argv[i] = ""
				if ( byte == "snd_cwnd" ) {
					snd_cwnd_flg = 1; continue };
				if ( byte == "snd_wnd" ) {
					snd_wnd_flg = 1;  continue };
				if ( byte == "srtt" ) {
					srtt_flg = 1;  continue };
%( kernel_v > "2.6.24" %?
				if ( byte == "state" ) {
					state_flg = 1;  continue };
%:
				state_flg = 0;
%)
				if ( byte == "txq" ) {
					txq_flg = 1;  continue };
				if ( byte == "rxq" ) {
					rxq_flg = 1;  continue };
				if ( byte == "rexmit" ) {
					rexmit_flg = 1;  continue };
				if ( byte == "pmtu" ) {
					pmtu_flg = 1;  continue };
				if ( byte == "ssthresh" ) {
					ssthresh_flg = 1;  continue };
				if ( byte == "timer" ) {
					timer_flg = 1;  continue };
				if ( byte == "rcvwnd" ) {
					rcvwnd_flg = 1;  continue };
				if ( byte == "length" ) {
					length_flg = 1; continue };
				if ( byte == "all" ) {
					snd_cwnd_flg = snd_wnd_flg = srtt_flg =
					txq_flg = rxq_flg =
					rexmit_flg = pmtu_flg = ssthresh_flg =
					timer_flg = rcvwnd_flg = length_flg = 1;
%( kernel_v > "2.6.24" %?
					state_flg = 1;
%)
					continue
				};
				usage("Unknown filter value given!")
                        }
                        continue;
                }

if ( argument == "timeout" ){
                        argv[i]=""
                        timeout=strtol(tokenize(argv[i], "="),10)
                        continue;
                }

if ( argument == "update") {
			argv[i]=""
			update_disp = tokenize(argv[i], "=")
			if (update_disp == "all")
				always_update = 1;
			continue;
		}

/* Anything on the command line after this point must
		 * be an address rule.
		 */
		source = tokenize(argv[i], "-")
			argv[i] = ""
		dest = tokenize(argv[i], "-")

source_addr = tokenize(source, ":")
			source=""
		source_port = tokenize(source, ":")

dest_addr = tokenize(dest, ":")
			dest=""
		dest_port = tokenize(dest, ":")

/* stap bug */
		if ( dest_port == "fobar") i=i;

++filter_number;
		j=filter_number*6;
		filter[j]   = ipv4_pton(source_addr,0)  // Source address
		filter[j+1] = ipv4_pton(source_addr,1)  // Source address mask
		filter[j+2] = ipv4_portton(source_port) // Source port
		filter[j+3] = ipv4_pton(dest_addr,0)    // Dest address
		filter[j+4] = ipv4_pton(dest_addr,1)    // Dest address mask
		filter[j+5] = ipv4_portton(dest_port)   // Dest port

if (filter[j]< -1 ||
			filter[j+1] < -1 ||
			filter[j+2] < -1 ||
			filter[j+3] < -1 ||
			filter[j+4] < -1 ||
			filter[j+5] < -1 ) return -1;

}

/* default filter is all */
	if ( !filter_given )
		snd_cwnd_flg = snd_wnd_flg = srtt_flg =
		txq_flg = rxq_flg =
		rexmit_flg = pmtu_flg = ssthresh_flg =
		timer_flg = rcvwnd_flg = length_flg = 1;
%( kernel_v > "2.6.24" %?
		state_flg = 1;
%)
	return filter_number;
}

/*
 * Convert an ascii integer values between 0 and 65534 to a u16 port number.
 * "*" are treated as wildcards and will be converted to -1.
 */
function ipv4_portton:long (port:string)
{
	if ( port == "*" )
		return -1;

pport=strtol(port,10);

if ( pport > 0xffff ){
		printf("Bad port number %s\n",port)
		return -22;
	}

return pport
}

/*
 * Convert ipv4 dot notation address into longs.
 * Supports "*" in any field treating it as a wildcard by making the byte=0.
 * If make_mask is set it creates a mask based on the "*" fields. All non='*'
 * bytes are set to 0xff all * fields are set to 0x0;.
 */
function ipv4_pton:long (addr:string, make_mask:long)
{
	i=32;
	ip=0;
	ips=addr;
	while(strlen(byte = tokenize(ips, ".")) != 0) {
		i-=8;
		ips="";

if ( byte == "*" ){
			byte = "0"
		} else {
			if ( make_mask ) byte = "255";
		}

j=strtol(byte,10);
		if ( j > 255 ){
			printf("bad address %s\n",addr)
			return -22;
		}
			ip=ip+(j<<i) // left shift the byte into the address
	}
	if ( i != 0 ){
		printf("bad address %s\n",addr)
		return -22;
	}
	return ip;
}

/*
 * Returns a unique value (stored in the global key_list) based on the socket
 * address tuple. A new value is created if one does not already exist.
 */
function build_key:long (laddr:long, raddr:long, lport:long, rport:long)
{
	if ( key_list[laddr, raddr, lport, rport] )
		return  key_list[laddr, raddr, lport, rport]
	else
		return key_list[laddr, raddr, lport, rport] = ++lastkey
}

/*
 * Checks the tuple against the rule list. If we pass through the rule
 * then return a unique key value, otherwise return zero.
 */
function filter_key:long (sk:long)
{
	laddr = tcpmib_local_addr(sk);
	raddr = tcpmib_remote_addr(sk);
	lport = tcpmib_local_port(sk);
	rport = tcpmib_remote_port(sk);

for (i=1; i <= number_of_rules; i++){
		j=i*6;

// Local filter
		local_filter=remote_filter=0;
		if ( (laddr&filter[j+1]) == filter[j] ) {
			if ( (filter[j+2] == -1 ) || (lport == filter[j+2]))
				local_filter = 1;
		}
		// Remote filter
		if ( (raddr&filter[j+4]) == filter[j+3] ) {
			if ( (filter[j+5] == -1 ) || (rport == filter[j+5]))
				remote_filter = 1;
		}
		if(local_filter && remote_filter){
			return build_key(laddr, raddr, lport, rport);
		}
	}
	return 0;
}

/* Free up a slot in the data arrays */
%( kernel_v > "2.6.24" %?
function clean_up (key:long)
{
	foreach ( [laddr, raddr, lport, rport] in key_list ){
		if ( key_list[laddr, raddr, lport, rport] == key ){
			break
		}
	}

delete key_list[laddr, raddr, lport, rport]

if (snd_cwnd_flg) delete snd_cwnd[key];
	if (snd_wnd_flg) delete snd_wnd[key];
	if (srtt_flg) delete srtt[key];
	if (state_flg) delete state[key];
	if (txq_flg) delete txq[key];
	if (rxq_flg) delete rxq[key];
	if (rexmit_flg) delete rexmit[key];
	if (pmtu_flg) delete pmtu[key];
	if (ssthresh_flg) delete ssthresh[key];
	if ( timer_flg ) {
		delete tx_timer[key];
		delete find_timer[key];
	}
	if (rcvwnd_flg) delete rcvwnd[key];
	delete length[key];
}
%)

/* Terminates the run in timeout seconds, using global timeout value */
probe timer.s(1) {
	if ( timeout == -1 ) next
	if ( !--timeout ) exit()
}

function usage (msg:string)
{
	printf("\nUsage:\n");
	printf("\ttcp_trace.stp  filter=<list of filters>[timeout=<sec>] \n");
	printf("\t\t\t[update=change|all] Rule\n\n");
	printf("\tRule format:");
	printf("<local address>:<local-port>-<remote address>:<remote-port>\n");
%( kernel_v > "2.6.24" %?
	printf("\tFilter values: all|state|txq|rxq|srtt|snd_cwnd|snd_wnd|\n");
%:
	printf("\tFilter values: all|txq|rxq|srtt|snd_cwnd|snd_wnd|\n");
%)
	printf("\t\t\trexmit|pmtu|ssthresh|timer|rcvwnd\n\n");
	printf("%s\n\n",msg);
	error(msg);
}

cmd: