#	$OpenBSD: dynamic-forward.sh,v 1.11 2015/03/03 22:35:19 markus Exp $
#	Placed in the Public Domain.

setglobal tid = '"dynamic forwarding'"

setglobal FWDPORT = $[expr $PORT + 1]

if have_prog nc && nc -h !2 > !1 | grep "proxy address" >/dev/null {
	setglobal proxycmd = ""nc -x 127.0.0.1:$FWDPORT -X""
} elif have_prog connect {
	setglobal proxycmd = ""connect -S 127.0.0.1:$FWDPORT -""
} else {
	echo "skipped (no suitable ProxyCommand found)"
	exit 0
}
trace "will use ProxyCommand $proxycmd"

start_sshd

for p in [$(SSH_PROTOCOLS)] {
	setglobal n = '0'
	setglobal error = '"1'"
	trace "start dynamic forwarding, fork to background"
	while test $error -ne 0 -a $n -lt 3 {
		setglobal n = $[expr $n + 1]
		$(SSH) -$p -F $OBJ/ssh_config -f -D $FWDPORT -q \
		    -oExitOnForwardFailure=yes somehost exec sh -c \
			'''"echo \$\$ > $OBJ/remote_pid; exec sleep 444"'''
		setglobal error = $Status
		if test $error -ne 0 {
			trace "forward failed proto $p attempt $n err $error"
			sleep $n
		}
	}
	if test $error -ne 0 {
		fatal "failed to start dynamic forwarding proto $p"
	}

	for s in [4 5] {
	    for h in [127.0.0.1 localhost] {
		trace "testing ssh protocol $p socks version $s host $h"
		$(SSH) -F $OBJ/ssh_config \
			-o "ProxyCommand $(proxycmd)$(s) $h $PORT" \
			somehost cat $DATA > $OBJ/ls.copy
		test -f $OBJ/ls.copy	 || fail "failed copy $DATA"
		cmp $DATA $OBJ/ls.copy || fail "corrupted copy of $DATA"
	    }
	}

	if test -f $OBJ/remote_pid {
		setglobal remote = $[cat $OBJ/remote_pid]
		trace "terminate remote shell, pid $remote"
		if test $remote -gt 1 {
			kill -HUP $remote
		}
	} else {
		fail "no pid file: $OBJ/remote_pid"
	}
}