From: Ian Jackson <ijackson@chiark.greenend.org.uk>
Date: Tue, 10 Oct 2017 13:35:34 +0000 (+0100)
Subject: modrelays-probe: wip
X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~webstump/git?a=commitdiff_plain;ds=sidebyside;h=eb3305d6e47dc86dbeba5bb6c9c499c9dee433c9;p=modbot-ulm.git

modrelays-probe: wip
---

diff --git a/probes/modrelays-probe b/probes/modrelays-probe
new file mode 100755
index 0000000..1c4ead4
--- /dev/null
+++ b/probes/modrelays-probe
@@ -0,0 +1,201 @@
+#!/bin/bash
+
+set -e
+
+id=$(date +%s)_$$
+
+fail () {
+	printf >&2 "%s\n" "modrelays-probe: error: $1"
+	exit 16
+}
+
+record-probing () {
+	# implicitly uses newsgroup, id, domain
+	# prints working dir filename
+	local probeid=$1
+
+	probeid=${probeid//[^=-.,_0-9A-Za-z]/%/}
+	case $probeid in
+	.*|*/*) fail "yikes, sanitisation bug!" ;;
+	esac
+
+	local newtd="monitoring/modrelays.probes/$probeid"
+	mkdir -p $newtd
+	printf "%s" $newtd
+}
+
+record-outcome () {
+	local probeid=$1
+	local outcome=$2
+	local message=$3
+	local td=`record-probing "$probeid"`
+	printf "%s\n" >"$td"/"$outcome"
+}
+
+record-success () { record-outcome "$1" ok '' }
+record-tempfail () { record-outcome "$1" tempfail "$2" }
+record-permfail () { record-outcome "$1" permfail "$2" }
+
+probe-addr () {
+	local mx=$1
+	local addr=$2
+
+	local td=`record-probing "mx=$mx,addr=$addr"`
+
+	set +e
+	swaks	--to "${GROUP//./-/}@$domain" \
+		--server $addr \
+		--tls-optional-strict \
+		--header 'Subject: test modrelays probe test' \
+		--header \
+	"X-WebSTUMP-Relay-Probe: $GROUP $id $domain $mx $addr" \
+		-n >$td/swaks.log 2>$td/swaks.err
+	rc=$?
+	set -e
+
+	case $rc in
+	0) return ;; # record-success done by receiver
+	esac
+	local permfail=''
+
+	local rhs
+	local prefix
+	local expect_no_5xx='initial connection'
+	while read <$td/swaks.log prefix rhs; do
+		case "$prefix" in
+		'<'*)
+			case "$rhs" in
+			5*)
+				if [ "x$expect_no_5xx" != x ] && \
+				   [ "x$permfail" = x ]; then
+					permfail="$rhs ($expect_no_5xx)" ;;
+				fi
+				;;
+			esac
+			;;
+		*'>')
+			case "$rhs" in
+			EHLO*|STARTTLS*) expect_no_5xx='' ;;
+			*) expect_no_5xx="after $rhs" ;;
+			esac
+			;;
+		*)
+	done
+
+	if [ "x$permfail" = x ]; then
+		record-tempfail "mx=$mx,addr=$addr" "see swaks.log / swaks.err"
+	else
+		record-permfail "mx=$mx,addr=$addr" "$permfail"
+	fi
+}
+
+probe-domain () {
+	local domain=$1
+	local td=`record-probing dns`
+	
+	set +e
+	adnshost -Fi -Tn +Do +Dt -t mx $domain >$td/dns
+	rc=$?
+	set -e
+
+	case $rc in
+	0)
+		# have a list of MX's
+		exec <$td/dns
+		local pref
+		local mx
+		local statustype
+		local rhs
+		while read pref mx statustype rhs; do
+			case $statustype in
+			0)
+				# have a list of relays
+				case $rhs in
+				*" ( "*")") ;;
+				*)
+					record-permfail "mx=$mx" \
+						"dns format $rhs"
+					continue
+				;;
+				rhs=${rhs%%* (}
+				rhs=${rhs# )}
+				local addr
+				for addr in $rhs; do
+					case $addr in
+					INET|INET6) continue ;;
+					esac
+					probe-addr $mx $addr
+				done
+				;;
+			[123])
+				# temporary errors
+				record-tempfail "mx=$mx" "dns $rc $rhs"
+				;;
+			*)
+				# yikes
+				record-permfail "mx=$mx" "dns $rc $rhs"
+				;;
+			esac
+		done
+		record-success dns
+		return
+		;;
+	6)
+		permfail, try A
+		set +e
+		adnshost -Fi -Tn +Do +Dt -t a $domain >$td
+		rc=$?
+		set -e
+		;;
+	esac
+
+	case $rc in
+	0)
+		# have a list of A's (dealt with MXs above)
+		exec <$td/dns
+		local addr
+		while read addr; do
+			probe-addr '<no-mx>' $addr
+		done
+		record-success dns
+		return
+		;;
+	[123])
+		local emsg
+		read <$td/dns emsg
+		record-tempfail dns "dns <no-mx> $emsg"
+		;;
+	*)
+		local emsg
+		read <$td/dns emsg
+		record-permfail dns "dns <no-mx> $emsg"
+		;;
+	esac
+}
+
+no_args () {
+	case $1 in
+	0) return ;;
+	*) fail
+
+mode_all () {
+	no_args $#
+	for domain in $MODRELAYS; do
+		probe $domain
+	done
+}
+
+mode_auto () {
+	no_args $#
+	xxx do something to cause sleeping
+	mode_all
+}
+
+mode_relay () {
+	relay="$1"
+	probe "$relay"
+}
+
+mode=$1; shift||:
+
+"mode_$mode" "$@"