ssh/test: skip tests on darwin that fail on the darwin-amd64-longtest LUCI builder

We don't yet understand why these tests fail, but the Apple sshd seems
to have some non-trivial vendor patches, so it is plausibly a
platform-specific bug in the test. Let's skip that failure mode on the
whole platform until/unless someone has time to reproduce and
investigate the failure.

For golang/go#64959.

Cq-Include-Trybots: luci.golang.try:x_crypto-gotip-darwin-amd64-longtest,x_crypto-gotip-linux-amd64-longtest,x_crypto-gotip-windows-amd64-longtest
Change-Id: I9e43579469de3fe9329c093b5916bbed0edd3751
Reviewed-on: https://go-review.googlesource.com/c/crypto/+/554077
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Nicola Murino <nicola.murino@gmail.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Bryan Mills <bcmills@google.com>

ssh/test/agent_unix_test.go

@@ -34,6 +34,7 @@ func TestAgentForward(t *testing.T) {
 
 	sess, err := conn.NewSession()
 	if err != nil {
+		skipIfIssue64959(t, err)
 		t.Fatalf("NewSession: %v", err)
 	}
 	if err := agent.RequestAgentForwarding(sess); err != nil {

ssh/test/dial_unix_test.go

@@ -53,6 +53,7 @@ func testDial(t *testing.T, n, listenAddr string, x dialTester) {
 	// on the opened connection.
 	cancel()
 	if err != nil {
+		skipIfIssue64959(t, err)
 		t.Fatalf("Dial: %v", err)
 	}
 	x.TestClientConn(t, conn)

ssh/test/forward_unix_test.go

@@ -12,6 +12,7 @@ import (
 	"io"
 	"math/rand"
 	"net"
+	"runtime"
 	"testing"
 	"time"
 )
@@ -27,6 +28,9 @@ func testPortForward(t *testing.T, n, listenAddr string) {
 
 	sshListener, err := conn.Listen(n, listenAddr)
 	if err != nil {
+		if runtime.GOOS == "darwin" && err == io.EOF {
+			t.Skipf("skipping test broken on some versions of macOS; see https://go.dev/issue/64959")
+		}
 		t.Fatal(err)
 	}
 
@@ -122,6 +126,9 @@ func testAcceptClose(t *testing.T, n, listenAddr string) {
 
 	sshListener, err := conn.Listen(n, listenAddr)
 	if err != nil {
+		if runtime.GOOS == "darwin" && err == io.EOF {
+			t.Skipf("skipping test broken on some versions of macOS; see https://go.dev/issue/64959")
+		}
 		t.Fatal(err)
 	}
 
@@ -163,6 +170,9 @@ func testPortForwardConnectionClose(t *testing.T, n, listenAddr string) {
 
 	sshListener, err := client.Listen(n, listenAddr)
 	if err != nil {
+		if runtime.GOOS == "darwin" && err == io.EOF {
+			t.Skipf("skipping test broken on some versions of macOS; see https://go.dev/issue/64959")
+		}
 		t.Fatal(err)
 	}
 

ssh/test/session_test.go

@@ -22,6 +22,13 @@ import (
 	"golang.org/x/crypto/ssh"
 )
 
+func skipIfIssue64959(t *testing.T, err error) {
+	if err != nil && runtime.GOOS == "darwin" && strings.Contains(err.Error(), "ssh: unexpected packet in response to channel open: <nil>") {
+		t.Helper()
+		t.Skipf("skipping test broken on some versions of macOS; see https://go.dev/issue/64959")
+	}
+}
+
 func TestRunCommandSuccess(t *testing.T) {
 	server := newServer(t)
 	conn := server.Dial(clientConfig())
@@ -29,6 +36,7 @@ func TestRunCommandSuccess(t *testing.T) {
 
 	session, err := conn.NewSession()
 	if err != nil {
+		skipIfIssue64959(t, err)
 		t.Fatalf("session failed: %v", err)
 	}
 	defer session.Close()
@@ -66,6 +74,7 @@ func TestRunCommandStdin(t *testing.T) {
 
 	session, err := conn.NewSession()
 	if err != nil {
+		skipIfIssue64959(t, err)
 		t.Fatalf("session failed: %v", err)
 	}
 	defer session.Close()
@@ -88,6 +97,7 @@ func TestRunCommandStdinError(t *testing.T) {
 
 	session, err := conn.NewSession()
 	if err != nil {
+		skipIfIssue64959(t, err)
 		t.Fatalf("session failed: %v", err)
 	}
 	defer session.Close()
@@ -111,6 +121,7 @@ func TestRunCommandFailed(t *testing.T) {
 
 	session, err := conn.NewSession()
 	if err != nil {
+		skipIfIssue64959(t, err)
 		t.Fatalf("session failed: %v", err)
 	}
 	defer session.Close()
@@ -127,6 +138,7 @@ func TestRunCommandWeClosed(t *testing.T) {
 
 	session, err := conn.NewSession()
 	if err != nil {
+		skipIfIssue64959(t, err)
 		t.Fatalf("session failed: %v", err)
 	}
 	err = session.Shell()
@@ -146,6 +158,7 @@ func TestFuncLargeRead(t *testing.T) {
 
 	session, err := conn.NewSession()
 	if err != nil {
+		skipIfIssue64959(t, err)
 		t.Fatalf("unable to create new session: %s", err)
 	}
 
@@ -182,6 +195,7 @@ func TestKeyChange(t *testing.T) {
 	for i := 0; i < 4; i++ {
 		session, err := conn.NewSession()
 		if err != nil {
+			skipIfIssue64959(t, err)
 			t.Fatalf("unable to create new session: %s", err)
 		}
 
@@ -223,6 +237,7 @@ func TestValidTerminalMode(t *testing.T) {
 
 	session, err := conn.NewSession()
 	if err != nil {
+		skipIfIssue64959(t, err)
 		t.Fatalf("session failed: %v", err)
 	}
 	defer session.Close()
@@ -287,6 +302,7 @@ func TestWindowChange(t *testing.T) {
 
 	session, err := conn.NewSession()
 	if err != nil {
+		skipIfIssue64959(t, err)
 		t.Fatalf("session failed: %v", err)
 	}
 	defer session.Close()
@@ -349,6 +365,7 @@ func testOneCipher(t *testing.T, cipher string, cipherOrder []string) {
 	// Exercise receiving data from the server
 	session, err := conn.NewSession()
 	if err != nil {
+		skipIfIssue64959(t, err)
 		t.Fatalf("NewSession: %v", err)
 	}