# -*- tab-width: 4 -*- ;; Emacs
# vi: set filetype=sh tabstop=8 shiftwidth=8 noexpandtab :: Vi/ViM
############################################################ IDENT(1)
#
# $Title: dwatch(8) module for dtrace_tcp(4) connections $
# $Copyright: 2014-2018 Devin Teske. All rights reserved. $
#
############################################################ DESCRIPTION
#
# Display local/remote TCP addresses/ports and bytes sent/received for TCP I/O
#
############################################################ PROBE

case "$PROFILE" in
tcp)
	: ${PROBE:=$( echo \
		tcp:::accept-established, \
		tcp:::accept-refused, \
		tcp:::connect-established, \
		tcp:::connect-refused, \
		tcp:::connect-request, \
		tcp:::receive, \
		tcp:::send, \
		tcp:::state-change )} ;;
tcp-accept)
	: ${PROBE:=tcp:::accept-established, tcp:::accept-refused} ;;
tcp-connect)
	: ${PROBE:=$( echo \
		tcp:::connect-established, \
		tcp:::connect-refused, \
		tcp:::connect-request )} ;;
tcp-established)
	: ${PROBE:=tcp:::accept-established, tcp:::connect-established} ;;
tcp-init)
	: ${PROBE:=$( echo \
		tcp:::accept-established, \
		tcp:::accept-refused, \
		tcp:::connect-established, \
		tcp:::connect-refused, \
		tcp:::connect-request )} ;;
tcp-io)
	: ${PROBE:=tcp:::send, tcp:::receive} ;;
tcp-refused)
	: ${PROBE:=tcp:::accept-refused, tcp:::connect-refused} ;;
tcp-status)
	: ${PROBE:=$( echo \
		tcp:::accept-established, \
		tcp:::accept-refused, \
		tcp:::connect-established, \
		tcp:::connect-refused, \
		tcp:::connect-request, \
		tcp:::state-change )} ;;
*)
	: ${PROBE:=tcp:::${PROFILE#tcp-}}
esac

############################################################ ACTIONS

exec 9<<EOF
this int32_t	from_state;
this int32_t	to_state;
this string	details;
this string	flow;
this string	local;
this string	remote;
this u_char	local6;
this u_char	remote6;
this u_char	slocal;
this uint16_t	lport;
this uint16_t	rport;
this uint32_t	length;

inline string probeflow[string name] =
	name == "accept-established" ?	"<-" :
	name == "accept-refused" ?	"X-" :
	name == "connect-refused" ?	"-X" :
	name == "connect-request" ?	"-?" :
	name == "receive" ?		"<-" :
	"->";

inline u_char srclocal[string name] =
	name == "accept-refused" ?	1 :
	name == "connect-request" ?	1 :
	name == "send" ?		1 :
	0;

/*
 * TCPSTATES from <sys/netinet/tcp_fsm.h> used by netstat(1)
 */
inline string tcpstate[int32_t state] =
        state == TCPS_CLOSED ?		"CLOSED" :
        state == TCPS_LISTEN ?		"LISTEN" :
        state == TCPS_SYN_SENT ?	"SYN_SENT" :
        state == TCPS_SYN_RECEIVED ?	"SYN_RCVD" :
        state == TCPS_ESTABLISHED ?	"ESTABLISHED" :
        state == TCPS_CLOSE_WAIT ?	"CLOSE_WAIT" :
        state == TCPS_FIN_WAIT_1 ?	"FIN_WAIT_1" :
        state == TCPS_CLOSING ?		"CLOSING" :
        state == TCPS_LAST_ACK ?	"LAST_ACK" :
        state == TCPS_FIN_WAIT_2 ?	"FIN_WAIT_2" :
        state == TCPS_TIME_WAIT ?	"TIME_WAIT" :
        strjoin("UNKNOWN(", strjoin(lltostr(state), ")"));

$PROBE /* probe ID $ID */
{${TRACE:+
	printf("<$ID>");}
	this->details = "";

	/*
	 * dtrace_tcp(4)
	 */
	this->flow = probeflow[probename];
}

tcp:::accept-established,
tcp:::accept-refused,
tcp:::connect-established,
tcp:::connect-refused,
tcp:::connect-request,
tcp:::receive,
tcp:::send /* probe ID $(( $ID + 1 )) */
{${TRACE:+
	printf("<$(( $ID + 1 ))>");
}
	/*
	 * dtrace_tcp(4)
	 */
	this->slocal = srclocal[probename];

	/*
	 * ipinfo_t *
	 */
	this->local  = this->slocal ? args[2]->ip_saddr : args[2]->ip_daddr;
	this->remote = this->slocal ? args[2]->ip_daddr : args[2]->ip_saddr;

	/*
	 * tcpinfo_t *
	 */
	this->lport = this->slocal ? args[4]->tcp_sport : args[4]->tcp_dport;
	this->rport = this->slocal ? args[4]->tcp_dport : args[4]->tcp_sport;

	/*
	 * IPv6 support
	 */
	this->local6 = strstr(this->local, ":") != NULL ? 1 : 0;
	this->remote6 = strstr(this->remote, ":") != NULL ? 1 : 0;
	this->local = strjoin(strjoin(this->local6 ? "[" : "",
		this->local), this->local6 ? "]" : "");
	this->remote = strjoin(strjoin(this->remote6 ? "[" : "",
		this->remote), this->remote6 ? "]" : "");
}

tcp:::state-change /* probe ID $(( $ID + 2 )) */
{${TRACE:+
	printf("<$(( $ID + 2 ))>");
}
	/*
	 * tcpsinfo_t *
	 */
	this->local    = args[3]->tcps_laddr;
	this->lport    = (uint16_t)args[3]->tcps_lport;
	this->remote   = args[3]->tcps_raddr;
	this->rport    = (uint16_t)args[3]->tcps_rport;
	this->to_state = (int32_t)args[3]->tcps_state;

	/*
	 * tcplsinfo_t *
	 */
	this->from_state = (int32_t)args[5]->tcps_state;

	/* flow = "[from state]->[to state]" */
	this->flow = strjoin(tcpstate[this->from_state],
		strjoin("->", tcpstate[this->to_state]));
}

tcp:::send, tcp:::receive /* pribe ID $(( $ID + 3 )) */
{${TRACE:+
	printf("<$(( $ID + 3 ))>");}
	this->length = (uint32_t)args[2]->ip_plength -
		(uint8_t)args[4]->tcp_offset;

	/* details = " <length> byte<s>" */
	this->details = strjoin(
		strjoin(" ", lltostr(this->length)),
		strjoin(" byte", this->length == 1 ? "" : "s"));
}
EOF
ACTIONS=$( cat <&9 )
ID=$(( $ID + 4 ))

############################################################ EVENT DETAILS

if [ ! "$CUSTOM_DETAILS" ]; then
exec 9<<EOF
	/*
	 * Print details
	 */
	printf("%s:%u %s %s:%u%s",
		this->local, this->lport,
		this->flow,
		this->remote, this->rport,
		this->details);
EOF
EVENT_DETAILS=$( cat <&9 )
fi

################################################################################
# END
################################################################################