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* [PATCH] test/utils: add more reliable "get remote address" approach
@ 2025-07-03 11:33 Alan Maguire
  2025-07-03 16:43 ` [DTrace-devel] " Eugene Loh
  0 siblings, 1 reply; 21+ messages in thread
From: Alan Maguire @ 2025-07-03 11:33 UTC (permalink / raw)
  To: dtrace; +Cc: dtrace-devel, Alan Maguire

The current approach of looking for remote addresses
is brittle and fails in many environments; it checks the
default route gateway and looks for open ports in the TCP
case.

We can however achieve the same goal reliably by creating
a network namespace on the system and configuring either
IPv4 or IPv6 addresses on the namespaced and local veth
interfaces that support communication between namespaces.
If a tcp port is required start sshd to listen on that port.

Teardown is managed in runtest.sh as signal handling for
timeouts within the test scripts is not working; a trap
function does not trigger for TERM.

Move the get_remote.sh script to test/utils also as it
seems a more natural location.

One issue - this cannot be run on a local system with
a VPN running as the VPN connection is pretty aggressive
in disconnecting/reconnecting when spotting a link-up event
associated with the global netns side of the veth.  However
in my experience the remote IP tests do not work reliably
in that environment anyway.

Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
---
 runtest.sh                                  |  2 +
 test/unittest/ip/get.ipv4remote.pl          | 87 ---------------------
 test/unittest/ip/get.ipv6remote.pl          | 70 -----------------
 test/unittest/ip/tst.ipv4remoteicmp.sh      | 10 +--
 test/unittest/ip/tst.ipv4remotetcp.sh       | 25 ++----
 test/unittest/ip/tst.ipv4remoteudp.sh       |  8 +-
 test/unittest/ip/tst.ipv6remoteicmp.sh      | 16 ++--
 test/unittest/tcp/tst.ipv4remotetcp.sh      | 24 ++----
 test/unittest/tcp/tst.ipv4remotetcpstate.sh | 29 +++----
 test/unittest/udp/tst.ipv4remoteudp.sh      |  4 +-
 test/utils/get_remote.sh                    | 71 +++++++++++++++++
 11 files changed, 116 insertions(+), 230 deletions(-)
 delete mode 100755 test/unittest/ip/get.ipv4remote.pl
 delete mode 100755 test/unittest/ip/get.ipv6remote.pl
 create mode 100755 test/utils/get_remote.sh

diff --git a/runtest.sh b/runtest.sh
index 156e7dec..9f06a499 100755
--- a/runtest.sh
+++ b/runtest.sh
@@ -1473,6 +1473,8 @@ for dt in $dtrace; do
 
         log "\n"
 
+	test/utils/get_remote.sh cleanup
+
         if [[ -n $regression ]]; then
             # If regtesting, we run a second time, with intermediate results
             # displayed, and output redirected to a per-test, per-dtrace
diff --git a/test/unittest/ip/get.ipv4remote.pl b/test/unittest/ip/get.ipv4remote.pl
deleted file mode 100755
index 3cc47d01..00000000
--- a/test/unittest/ip/get.ipv4remote.pl
+++ /dev/null
@@ -1,87 +0,0 @@
-#!/usr/bin/perl -w
-#
-# Oracle Linux DTrace.
-# Copyright (c) 2008, 2017, Oracle and/or its affiliates. All rights reserved.
-# Licensed under the Universal Permissive License v 1.0 as shown at
-# http://oss.oracle.com/licenses/upl.
-#
-
-#
-# get.ipv4remote.pl [tcpport]
-#
-# Find an IPv4 reachable remote host using both ip(8) and ping(8).
-# If a tcpport is specified, return a host that is also listening on this
-# TCP port.  Print the local address and the remote address, or an
-# error message if no suitable remote host was found.  Exit status is 0 if
-# a host was found.  (Note: the only host we check is the gateway.  Nobody
-# responds to broadcast pings these days, and portscanning the local net is
-# unfriendly.)
-#
-
-use strict;
-use IO::Socket;
-
-my $TIMEOUT = 3;
-my $tcpport = @ARGV == 1 ? $ARGV[0] : 0;
-
-#
-# Determine gateway IP address
-#
-
-my $local = "";
-my $remote = "";
-my $responsive = "";
-my $up;
-open IP, '/sbin/ip -o -4 route show |' or die "Couldn't run ip route show: $!\n";
-while (<IP>) {
-	next unless /^default /;
-
-	if (/via (\S+)/) {
-		$remote = $1;
-	}
-}
-close IP;
-die "Could not determine gateway router IP address" if $remote eq "";
-
-open IP, "/sbin/ip -o route get to $remote |" or die "Couldn't run ip route get: $!\n";
-while (<IP>) {
-	next unless /^$remote /;
-	if (/src (\S+)/) {
-		$local = $1;
-	}
-}
-close IP;
-die "Could not determine local IP address" if $local eq "";
-
-#
-# See if the rmote host responds to an icmp echo.
-#
-open PING, "/bin/ping -n -s 56 -w $TIMEOUT $remote |" or
-    die "Couldn't run ping: $!\n";
-while (<PING>) {
-	if (/bytes from (.*): /) {
-		my $addr = $1;
-
-		if ($tcpport != 0) {
-			#
-			# Test TCP
-			#
-			my $socket = IO::Socket::INET->new(
-				Proto    => "tcp",
-				PeerAddr => $addr,
-				PeerPort => $tcpport,
-				Timeout  => $TIMEOUT,
-			);
-			next unless $socket;
-			close $socket;
-		}
-
-		$responsive = $addr;
-		last;
-	}
-}
-close PING;
-die "Can't find a remote host for testing: No suitable response from " .
-    "$remote\n" if $responsive eq "";
-
-print "$local $responsive\n";
diff --git a/test/unittest/ip/get.ipv6remote.pl b/test/unittest/ip/get.ipv6remote.pl
deleted file mode 100755
index b2136c5b..00000000
--- a/test/unittest/ip/get.ipv6remote.pl
+++ /dev/null
@@ -1,70 +0,0 @@
-#!/usr/bin/perl -w
-#
-# Oracle Linux DTrace.
-# Copyright (c) 2008, 2017, Oracle and/or its affiliates. All rights reserved.
-# Licensed under the Universal Permissive License v 1.0 as shown at
-# http://oss.oracle.com/licenses/upl.
-#
-
-#
-# get.ipv6remote.pl
-#
-# Find an IPv6 reachable remote host using both ip(8) and ping(8).
-# Print the local address and the remote address, or print nothing if either
-# no IPv6 interfaces or remote hosts were found.  (Remote IPv6 testing is
-# considered optional, and so not finding another IPv6 host is not an error
-# state we need to log.)  Exit status is 0 if a host was found.
-#
-
-use strict;
-use IO::Socket;
-
-my $TIMEOUT = 3;			# connection timeout
-
-# possible paths for ping6
-$ENV{'PATH'} = "/bin:/usr/bin:/sbin:/usr/sbin:$ENV{'PATH'}";
-
-#
-# Determine local IP address
-#
-my $local = "";
-my $remote = "";
-my $responsive = "";
-my $up;
-open IP, '/sbin/ip -o -6 route show |' or die "Couldn't run ip route show: $!\n";
-while (<IP>) {
-	next unless /^default /;
-
-	if (/via (\S+)/) {
-		$remote = $1;
-	}
-}
-close IP;
-die "Could not determine gateway router IPv6 address" if $remote eq "";
-
-open IP, "/sbin/ip -o route get to $remote |" or die "Couldn't run ip route get: $!\n";
-while (<IP>) {
-	next unless /^$remote /;
-	if (/src (\S+)/) {
-		$local = $1;
-	}
-}
-close IP;
-die "Could not determine local IPv6 address" if $local eq "";
-
-#
-# Find the first remote host that responds to an icmp echo,
-# which isn't a local address.
-#
-open PING, "ping6 -n -s 56 -w $TIMEOUT $remote 2>/dev/null |" or
-    die "Couldn't run ping: $!\n";
-while (<PING>) {
-	if (/bytes from (.*): /) {
-		$responsive = $1;
-		last;
-	}
-}
-close PING;
-exit 2 if $responsive eq "";
-
-print "$local $responsive\n";
diff --git a/test/unittest/ip/tst.ipv4remoteicmp.sh b/test/unittest/ip/tst.ipv4remoteicmp.sh
index c165cbdc..854797a7 100755
--- a/test/unittest/ip/tst.ipv4remoteicmp.sh
+++ b/test/unittest/ip/tst.ipv4remoteicmp.sh
@@ -13,9 +13,7 @@
 #
 # 1. A change to the ip stack breaking expected probe behavior,
 #    which is the reason we are testing.
-# 2. No physical network interface is plumbed and up.
-# 3. The subnet gateway is not reachable.
-# 4. An unrelated ICMP between these hosts was traced by accident.
+# 2. An unrelated ICMP between these hosts was traced by accident.
 #
 
 if (( $# != 1 )); then
@@ -25,18 +23,20 @@ fi
 
 dtrace=$1
 testdir="$(dirname $_test)"
-getaddr=$testdir/get.ipv4remote.pl
+getaddr=$testdir/../../utils/get_remote.sh
 
 if [[ ! -x $getaddr ]]; then
 	echo "could not find or execute sub program: $getaddr" >&2
 	exit 3
 fi
-set -- $($getaddr)
+
+set -- $($getaddr ipv4)
 source="$1"
 dest="$2"
 if [[ $? -ne 0 ]] || [[ -z $dest ]]; then
 	exit 67
 fi
+
 $dtrace $dt_flags -c "$testdir/perlping.pl icmp $dest" -qs /dev/stdin <<EOF | \
 	sort -n
 ip:::send
diff --git a/test/unittest/ip/tst.ipv4remotetcp.sh b/test/unittest/ip/tst.ipv4remotetcp.sh
index 577c5668..f164d9d0 100755
--- a/test/unittest/ip/tst.ipv4remotetcp.sh
+++ b/test/unittest/ip/tst.ipv4remotetcp.sh
@@ -13,9 +13,7 @@
 #
 # 1. A change to the ip stack breaking expected probe behavior,
 #    which is the reason we are testing.
-# 2. No physical network interface is plumbed and up.
-# 3. The subnet gateway is not reachable and listening on ssh.
-# 4. An unlikely race causes the unlocked global send/receive
+# 2. An unlikely race causes the unlocked global send/receive
 #    variables to be corrupted.
 #
 # This test performs a TCP connection and checks that at least the
@@ -32,27 +30,20 @@ fi
 
 dtrace=$1
 testdir="$(dirname $_test)"
-getaddr=$testdir/get.ipv4remote.pl
-tcpports="22 80"
-tcpport=""
+getaddr=$testdir/../../utils/get_remote.sh
+tcpport="22"
 dest=""
 
 if [[ ! -x $getaddr ]]; then
 	echo "could not find or execute sub program: $getaddr" >&2
 	exit 3
 fi
-for port in $tcpports ; do
-	res=`$getaddr $port 2>/dev/null`
-	if (( $? == 0 )); then
-		read s d <<< $res
-		tcpport=$port
-		source=$s
-		dest=$d
-		break
-        fi
-done
 
-if [ -z $tcpport ]; then
+set -- $($getaddr ipv4 $tcpport)
+source="$1"
+dest="$2"
+
+if [[ $? -ne 0 ]] || [[ -z $dest ]]; then
 	exit 67
 fi
 
diff --git a/test/unittest/ip/tst.ipv4remoteudp.sh b/test/unittest/ip/tst.ipv4remoteudp.sh
index 3d25e1f5..f88ab35b 100755
--- a/test/unittest/ip/tst.ipv4remoteudp.sh
+++ b/test/unittest/ip/tst.ipv4remoteudp.sh
@@ -13,9 +13,7 @@
 #
 # 1. A change to the ip stack breaking expected probe behavior,
 #    which is the reason we are testing.
-# 2. No physical network interface is plumbed and up.
-# 3. The gateway is not reachable and listening on rpcbind.
-# 4. An unlikely race causes the unlocked global send/receive
+# 2. An unlikely race causes the unlocked global send/receive
 #    variables to be corrupted.
 #
 # This test sends a UDP message using ping and checks that at least the
@@ -31,13 +29,13 @@ fi
 
 dtrace=$1
 testdir="$(dirname $_test)"
-getaddr=$testdir/get.ipv4remote.pl
+getaddr=$testdir/../../utils/get_remote.sh
 
 if [[ ! -x $getaddr ]]; then
 	echo "could not find or execute sub program: $getaddr" >&2
 	exit 3
 fi
-set -- $($getaddr)
+set -- $($getaddr ipv4)
 source="$1"
 dest="$2"
 if [[ $? -ne 0 ]] || [[ -z $dest ]]; then
diff --git a/test/unittest/ip/tst.ipv6remoteicmp.sh b/test/unittest/ip/tst.ipv6remoteicmp.sh
index 90fd48b4..0107a3ae 100755
--- a/test/unittest/ip/tst.ipv6remoteicmp.sh
+++ b/test/unittest/ip/tst.ipv6remoteicmp.sh
@@ -19,7 +19,7 @@
 #
 # @@tags: unstable
 
-# possible paths for ping6
+# possible paths for ping
 export PATH=/bin:/usr/bin:/sbin:/usr/sbin:$PATH
 
 if (( $# != 1 )); then
@@ -29,24 +29,24 @@ fi
 
 dtrace=$1
 testdir="$(dirname $_test)"
-getaddr=$testdir/get.ipv6remote.pl
+getaddr=$testdir/../../utils/get_remote.sh
 
 if [[ ! -x $getaddr ]]; then
 	echo "could not find or execute sub program: $getaddr" >&2
 	exit 3
 fi
-set -- $($getaddr)
+
+set -- $($getaddr ipv6)
 source="$1"
 dest="$2"
+
 if [[ $? -ne 0 ]] || [[ -z $dest ]]; then
 	echo -n "Could not find a local IPv6 interface and a remote IPv6 " >&2
 	echo "host.  Aborting test." >&2
 	exit 67
 fi
 
-nolinkdest="$(printf "%s" "$dest" | sed 's,%.*,,')"
-
-$dtrace $dt_flags -c "ping6 -c 6 $dest" -qs /dev/stdin <<EOF | \
+$dtrace $dt_flags -c "ping -6 -c 10 $dest" -qs /dev/stdin <<EOF | \
     gawk '/ip:::/ { print $0 }' | sort -n
 /* 
  * We use a size match to include only things that are big enough to
@@ -54,7 +54,7 @@ $dtrace $dt_flags -c "ping6 -c 6 $dest" -qs /dev/stdin <<EOF | \
  */
 
 ip:::send
-/args[2]->ip_saddr == "$source" && args[2]->ip_daddr == "$nolinkdest" &&
+/args[2]->ip_saddr == "$source" && args[2]->ip_daddr == "$dest" &&
     args[5]->ipv6_nexthdr == IPPROTO_ICMPV6 && args[2]->ip_plength > 32/
 {
 	printf("1 ip:::send    (");
@@ -64,7 +64,7 @@ ip:::send
 }
 
 ip:::receive
-/args[2]->ip_saddr == "$nolinkdest" && args[2]->ip_daddr == "$source" &&
+/args[2]->ip_saddr == "$dest" && args[2]->ip_daddr == "$source" &&
     args[5]->ipv6_nexthdr == IPPROTO_ICMPV6 && args[2]->ip_plength > 32/
 {
 	printf("2 ip:::receive (");
diff --git a/test/unittest/tcp/tst.ipv4remotetcp.sh b/test/unittest/tcp/tst.ipv4remotetcp.sh
index 333760a1..d8673d4b 100755
--- a/test/unittest/tcp/tst.ipv4remotetcp.sh
+++ b/test/unittest/tcp/tst.ipv4remotetcp.sh
@@ -13,9 +13,7 @@
 #
 # 1. A change to the tcp stack breaking expected probe behavior,
 #    which is the reason we are testing.
-# 2. No physical network interface is plumbed and up.
-# 3. No other hosts on this subnet are reachable and listening on ssh.
-# 4. An unlikely race causes the unlocked global send/receive
+# 2. An unlikely race causes the unlocked global send/receive
 #    variables to be corrupted.
 #
 # This test performs a TCP connection and checks that at least the
@@ -32,9 +30,8 @@ fi
 
 dtrace=$1
 testdir="$(dirname $_test)"
-getaddr=$testdir/../ip/get.ipv4remote.pl
-tcpports="22 80"
-tcpport=""
+getaddr=$testdir/../../utils/get_remote.sh
+tcpport="22"
 dest=""
 
 if [[ ! -x $getaddr ]]; then
@@ -42,18 +39,11 @@ if [[ ! -x $getaddr ]]; then
         exit 3
 fi
 
-for port in $tcpports ; do
-	res=`$getaddr $port 2>/dev/null`
-	if (( $? == 0 )); then
-		read s d <<< $res
-		tcpport=$port
-		source=$s
-		dest=$d
-		break
-	fi
-done
+set -- $($getaddr ipv4 $tcpport)
+source="$1"
+dest="$2"
 
-if [[ -z $tcpport ]]; then
+if [[ $? -ne 0 ]] || [[ -z $dest ]]; then
 	exit 67
 fi
 
diff --git a/test/unittest/tcp/tst.ipv4remotetcpstate.sh b/test/unittest/tcp/tst.ipv4remotetcpstate.sh
index 74fb4ce3..e9ff218d 100755
--- a/test/unittest/tcp/tst.ipv4remotetcpstate.sh
+++ b/test/unittest/tcp/tst.ipv4remotetcpstate.sh
@@ -17,8 +17,7 @@
 #
 # 1. A change to the ip stack breaking expected probe behavior,
 #    which is the reason we are testing.
-# 2. The remote ssh service is not online.
-# 3. An unlikely race causes the unlocked global send/receive
+# 2. An unlikely race causes the unlocked global send/receive
 #    variables to be corrupted.
 #
 # This test performs a TCP connection to the ssh service (port 22) and
@@ -40,29 +39,21 @@ fi
 
 dtrace=$1
 testdir="$(dirname $_test)"
-getaddr=$testdir/../ip/get.ipv4remote.pl
+getaddr=$testdir/../../utils/get_remote.sh
 client=$testdir/../ip/client.ip.pl
-tcpports="22 80"
-tcpport=""
-dest=""
+tcpport="22"
 
 if [[ ! -x $getaddr ]]; then
 	echo "could not find or execute sub program: $getaddr" >&2
 	exit 3
 fi
-for port in $tcpports ; do
-	res=`$getaddr $port 2>/dev/null`
-	if (( $? == 0 )); then
-		read s d <<< $res
-		tcpport=$port
-		source=$s
-		dest=$d
-		break
-	fi
-done
-
-if [ -z $tcpport ]; then
-        exit 67
+
+set -- $($getaddr ipv4 $tcpport)
+source="$1"
+dest="$2"
+
+if [[ $? -ne 0 ]] || [[ -z $dest ]]; then
+	exit 67
 fi
 
 
diff --git a/test/unittest/udp/tst.ipv4remoteudp.sh b/test/unittest/udp/tst.ipv4remoteudp.sh
index 1c5f2a9a..4fe70f5a 100755
--- a/test/unittest/udp/tst.ipv4remoteudp.sh
+++ b/test/unittest/udp/tst.ipv4remoteudp.sh
@@ -34,14 +34,14 @@ fi
 
 dtrace=$1
 testdir="$(dirname $_test)"
-getaddr=$testdir/../ip/get.ipv4remote.pl
+getaddr=$testdir/../../utils/get_remote.sh
 port=31337
 
 if [[ ! -x $getaddr ]]; then
 	echo "could not find or execute sub program: $getaddr" >&2
 	exit 3
 fi
-read source dest <<<`$getaddr 2>/dev/null`
+read source dest <<<`$getaddr ipv4 2>/dev/null`
 if (( $? != 0 )) || [[ -z $dest ]]; then
 	exit 67
 fi
diff --git a/test/utils/get_remote.sh b/test/utils/get_remote.sh
new file mode 100755
index 00000000..d8a4d450
--- /dev/null
+++ b/test/utils/get_remote.sh
@@ -0,0 +1,71 @@
+#!/bin/bash
+#
+# Oracle Linux DTrace.
+# Copyright (c) 2025, Oracle and/or its affiliates. All rights reserved.
+# Licensed under the Universal Permissive License v 1.0 as shown at
+# http://oss.oracle.com/licenses/upl.
+#
+
+#
+# get_remote.sh ipv4|ipv6|cleanup [tcpport]
+#
+# Create (or cleanup) a network namespace with either IPv4 or IPv6
+# address associated.
+#
+# Print the local address and the remote address, or an
+# error message if a failure occurred during setup.
+#
+# If tcpport is specified, start sshd on that port.
+#
+# Exit status is 0 if all succceeded.
+#
+
+cmd=$1
+tcpport=$2
+
+prefix=$(basename $tmpdir)
+netns=${prefix}ns
+veth1=${prefix}v1
+veth2=${prefix}v2
+mtu=1500
+
+set -e
+
+case $cmd in
+cleanup)	pids=$(ip netns pids ${netns} 2>/dev/null)
+		if [[ -n "$pids" ]]; then
+			kill -TERM $pids
+		fi
+		ip netns del ${netns} 2>/dev/null
+		exit 0
+		;;
+ ipv4)		veth1_addr=192.168.168.1
+		veth2_addr=192.168.168.2
+		prefixlen=24
+		family=
+		;;
+ ipv6)		veth1_addr=fd::1
+		veth2_addr=fd::2
+		prefixlen=64
+		family=-6
+		;;
+ *)		echo "Unexpected cmd $cmd" >2
+		exit 1
+		;;
+esac
+
+ip netns add $netns
+ip link add dev $veth1 mtu $mtu netns $netns type veth \
+   peer name $veth2 mtu $mtu
+ip netns exec $netns ip $family addr add ${veth1_addr}/$prefixlen dev $veth1
+ip netns exec $netns ip link set $veth1 up
+ip addr add ${veth2_addr}/${prefixlen} dev $veth2
+ip link set $veth2 up
+
+if [[ -n "$tcpport" ]]; then
+	sshd=$(which sshd)
+	ip netns exec $netns $sshd -p $tcpport &
+fi
+
+echo "$veth2_addr $veth1_addr"
+exit 0
-- 
2.43.5


^ permalink raw reply related	[flat|nested] 21+ messages in thread
end of thread, other threads:[~2025-07-08 20:13 UTC | newest]

Thread overview: 21+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2025-07-03 11:33 [PATCH] test/utils: add more reliable "get remote address" approach Alan Maguire
2025-07-03 16:43 ` [DTrace-devel] " Eugene Loh
2025-07-03 16:59   ` Alan Maguire
2025-07-03 17:06     ` Eugene Loh
2025-07-03 18:02       ` Alan Maguire
2025-07-03 18:26         ` Kris Van Hees
2025-07-03 18:41           ` Alan Maguire
2025-07-03 19:03             ` Kris Van Hees
2025-07-03 20:23               ` Alan Maguire
2025-07-03 20:59                 ` Kris Van Hees
2025-07-03 22:36                   ` Kris Van Hees
2025-07-07 16:32                     ` Alan Maguire
2025-07-07 16:53                       ` Kris Van Hees
2025-07-07 18:14                         ` Alan Maguire
2025-07-07 19:55                           ` Kris Van Hees
2025-07-07 21:51                             ` Alan Maguire
2025-07-08  1:34                               ` Kris Van Hees
2025-07-08 17:19                                 ` Alan Maguire
2025-07-08 17:30                                   ` Kris Van Hees
2025-07-08 19:04                                     ` Alan Maguire
2025-07-08 20:13                                       ` Kris Van Hees

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