upstream: regression test for "interactive" ssh with a PTY attached,

using tmux

would have likely caught the ControlPersist regression in 10.1.

feedback nicm@

OpenBSD-Regress-ID: d4d709c08657769cb5691893cc98f34b6f537e76

Author: djmdjm

regress/Makefile

@@ -19,6 +19,7 @@ clean:
 	for F in $(CLEANFILES); do rm -f $(OBJ)$$F; done
 	rm -rf $(OBJ).putty
 	rm -rf $(OBJ).dropbear
+	rm -rf $(OBJ).fakehome
 
 distclean:	clean
 
@@ -115,7 +116,8 @@ LTESTS= 	connect \
 		penalty \
 		penalty-expire \
 		connect-bigconf \
-		ssh-pkcs11
+		ssh-pkcs11 \
+		ssh-tty
 
 INTEROP_TESTS=	putty-transfer putty-ciphers putty-kex conch-ciphers
 INTEROP_TESTS+=	dropbear-ciphers dropbear-kex dropbear-server
@@ -153,7 +155,7 @@ CLEANFILES=	*.core actual agent-key.* authorized_keys_${USERNAME} \
 		t2.out t3.out t6.out1 t6.out2 t7.out t7.out.pub \
 		t8.out t8.out.pub t9.out t9.out.pub \
 		timestamp testdata user_*key* user_ca* user_key* \
-		pin.sh nopin.sh wrongpin.sh key.pub
+		pin.sh nopin.sh wrongpin.sh key.pub test.sh ctl-sock
 
 # Enable all malloc(3) randomisations and checks
 TEST_ENV=      "MALLOC_OPTIONS=CFGJRSUX"

regress/ssh-tty.sh

@@ -0,0 +1,152 @@
+#	$OpenBSD: ssh-tty.sh,v 1.1 2025/10/20 00:45:10 djm Exp $
+#	Placed in the Public Domain.
+
+# Basic TTY smoke test
+
+tid="ssh-tty"
+
+# Fake home directory to avoid user shell configuration.
+FAKEHOME="$OBJ/.fakehome"
+rm -rf "$FAKEHOME"
+mkdir -m 0700 -p "$FAKEHOME"
+
+# tmux stuff
+TMUX=tmux
+test -x $TMUX || skip "tmux not found"
+CLEANENV="env -i HOME=$HOME LOGNAME=$USER USER=$USER PATH=$PATH SHELL=$SHELL"
+TMUX_TEST="$CLEANENV $TMUX -f/dev/null -Lopenssh-regress-ssh-tty"
+sess="regress-ssh-tty$$"
+
+# Multiplexing control socket.
+CTL=$OBJ/ctl-sock
+
+# Some randomish strings used for signalling back and forth.
+# We use the octal variants via printf(1).
+MAGIC1="XY23zzY"
+MAGIC1_OCTAL="\130\131\062\063\172\172\131"
+MAGIC2="99sMarT86"
+MAGIC2_OCTAL="\071\071\163\115\141\162\124\070\066"
+MAGIC3="woLF1701d"
+MAGIC3_OCTAL="\167\157\114\106\061\067\060\061\144"
+MAGIC4="lUh4thX4evR"
+MAGIC4_OCTAL="\154\125\150\064\164\150\130\064\145\166\122"
+
+# Wait for a mux process to become ready.
+wait_for_mux_ready()
+{
+	for i in 1 2 3 4 5 6 7 8 9; do
+		${SSH} -F $OBJ/ssh_config -S $CTL -Ocheck otherhost \
+		    >/dev/null 2>&1 && return 0
+		sleep $i
+	done
+	fatal "mux never becomes ready"
+}
+
+# Wait for a mux process to have finished.
+wait_for_mux_done()
+{
+	for i in 1 2 3 4 5 6 7 8 9; do
+		test -S $CTL || return 0
+		sleep $i
+	done
+	fatal "mux socket never removed"
+}
+
+# Wait for a regex to appear in terminal output.
+wait_for_regex() {
+	string="$1"
+	errors_are_fatal="$2"
+	for x in 1 2 3 4 5 6 7 8 9 10 ; do
+		$TMUX_TEST capture-pane -pt $sess | grep "$string" >/dev/null
+		[ $? -eq 0 ] && return
+		sleep 1
+	done
+	if test -z "$errors_are_fatal"; then
+		fail "failed to match \"$string\" in terminal output"
+		return
+	fi
+	fatal "failed to match \"$string\" in terminal output"
+}
+
+# Check that a regex does *not* appear in terminal output
+not_in_term() {
+	string="$1"
+	error="$2"
+	errors_are_fatal="$3"
+	$TMUX_TEST capture-pane -pt $sess | grep "$string" > /dev/null
+	[ $? -ne 0 ] && return
+	if test -z "$errors_are_fatal"; then
+		fail "$error"
+		return
+	fi
+	fatal "$error"
+}
+
+trap "$TMUX_TEST kill-session -t $sess 2>/dev/null" EXIT
+
+run_test() {
+	tag="$1"
+	ssh_args="$2"
+	# Prepare a tmux session.
+	$TMUX_TEST kill-session -t $sess 2>/dev/null
+	$TMUX_TEST new-session -d -s $sess
+	#echo XXXXXXXXXX $sess; sleep 10
+
+	# Command to start SSH; sent as keystrokes to tmux session.
+	RCMD="$CLEANENV $SHELL"
+	CMD="$SSH -F $OBJ/ssh_proxy $ssh_args -S $CTL x -tt $RCMD"
+
+	verbose "${tag}: start connection"
+	# arrange for the shell to print something after ssh completes.
+	$TMUX_TEST send-keys -t $sess "$CMD && printf '$MAGIC1_OCTAL\n'" ENTER
+	wait_for_mux_ready
+
+	verbose "${tag}: send string"
+	$TMUX_TEST send-keys -t $sess "printf '$MAGIC2_OCTAL\n'" ENTER
+	wait_for_regex "$MAGIC2"
+
+	verbose "${tag}: ^c interrupts process"
+	# ^c should interrupt the sleep and prevent the magic string
+	# from appearing.
+	$TMUX_TEST send-keys -t $sess "sleep 30 || printf '$MAGIC3_OCTAL\n'"
+	$TMUX_TEST send-keys -t $sess ENTER
+	$TMUX_TEST send-keys -t $sess "C-c"
+	# send another string to let us know that the sleep has finished.
+	$TMUX_TEST send-keys -t $sess "printf '$MAGIC4_OCTAL\n'" ENTER
+	wait_for_regex "$MAGIC4"
+	not_in_term "$MAGIC3" "^c did not interrupt"
+
+	verbose "${tag}: ~? produces help"
+	$TMUX_TEST send-keys -t $sess ENTER "~?"
+	wait_for_regex "^Supported escape sequences:$"
+
+	verbose "${tag}: ~. terminates session"
+	$TMUX_TEST send-keys -t $sess ENTER "~."
+	wait_for_mux_done
+	not_in_term "$MAGIC1" "ssh unexpectedly exited successfully after ~."
+
+	verbose "${tag}: restart session"
+	$TMUX_TEST send-keys -t $sess "$CMD && printf '$MAGIC1_OCTAL\n'" ENTER
+	wait_for_mux_ready
+
+	verbose "${tag}: eof terminates session successfully"
+	$TMUX_TEST send-keys -t $sess ENTER "C-d"
+	wait_for_regex "$MAGIC1"
+}
+
+# Make sure tmux is working as expected before we start.
+$TMUX_TEST kill-session -t $sess 2>/dev/null
+$TMUX_TEST new-session -d -s $sess
+# Make sure the session doesn't contain the magic strings we will use
+# for signalling or any #? output.
+not_in_term "$MAGIC1" "terminal already contains magic1 string" fatal
+not_in_term "$MAGIC2" "terminal already contains magic2 string" fatal
+not_in_term "$MAGIC3" "terminal already contains magic3 string" fatal
+not_in_term "$MAGIC4" "terminal already contains magic4 string" fatal
+not_in_term "^Supported escape" "terminal already contains escape help" fatal
+$TMUX_TEST send-keys -t $sess "printf '$MAGIC1_OCTAL\n'" ENTER
+wait_for_regex "$MAGIC1" fatal
+$TMUX_TEST kill-session -t $sess 2>/dev/null
+
+run_test "basic" "-oControlMaster=yes"
+run_test "ControlPersist" "-oControlMaster=auto -oControlPersist=1s"