tempfork: temporarily fork gliderlabs/ssh and x/crypto/ssh

While we rearrange/upstream things.

gliderlabs/ssh is forked into tempfork from our prior fork
at be8b7add40

x/crypto/ssh OTOH is forked at
https://github.com/tailscale/golang-x-crypto because it was gnarlier
to vendor with various internal packages, etc.
Its git history shows where it starts (2c7772ba30643b7a2026cbea938420dce7c6384d).

Updates #3802

Change-Id: I546e5cdf831cfc030a6c42557c0ad2c58766c65f
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>

tempfork/gliderlabs/ssh/server_test.go

@@ -0,0 +1,129 @@
+//go:build glidertests
+// +build glidertests
+
+package ssh
+
+import (
+	"bytes"
+	"context"
+	"io"
+	"testing"
+	"time"
+)
+
+func TestAddHostKey(t *testing.T) {
+	s := Server{}
+	signer, err := generateSigner()
+	if err != nil {
+		t.Fatal(err)
+	}
+	s.AddHostKey(signer)
+	if len(s.HostSigners) != 1 {
+		t.Fatal("Key was not properly added")
+	}
+	signer, err = generateSigner()
+	if err != nil {
+		t.Fatal(err)
+	}
+	s.AddHostKey(signer)
+	if len(s.HostSigners) != 1 {
+		t.Fatal("Key was not properly replaced")
+	}
+}
+
+func TestServerShutdown(t *testing.T) {
+	l := newLocalListener()
+	testBytes := []byte("Hello world\n")
+	s := &Server{
+		Handler: func(s Session) {
+			s.Write(testBytes)
+			time.Sleep(50 * time.Millisecond)
+		},
+	}
+	go func() {
+		err := s.Serve(l)
+		if err != nil && err != ErrServerClosed {
+			t.Fatal(err)
+		}
+	}()
+	sessDone := make(chan struct{})
+	sess, _, cleanup := newClientSession(t, l.Addr().String(), nil)
+	go func() {
+		defer cleanup()
+		defer close(sessDone)
+		var stdout bytes.Buffer
+		sess.Stdout = &stdout
+		if err := sess.Run(""); err != nil {
+			t.Fatal(err)
+		}
+		if !bytes.Equal(stdout.Bytes(), testBytes) {
+			t.Fatalf("expected = %s; got %s", testBytes, stdout.Bytes())
+		}
+	}()
+
+	srvDone := make(chan struct{})
+	go func() {
+		defer close(srvDone)
+		err := s.Shutdown(context.Background())
+		if err != nil {
+			t.Fatal(err)
+		}
+	}()
+
+	timeout := time.After(2 * time.Second)
+	select {
+	case <-timeout:
+		t.Fatal("timeout")
+		return
+	case <-srvDone:
+		// TODO: add timeout for sessDone
+		<-sessDone
+		return
+	}
+}
+
+func TestServerClose(t *testing.T) {
+	l := newLocalListener()
+	s := &Server{
+		Handler: func(s Session) {
+			time.Sleep(5 * time.Second)
+		},
+	}
+	go func() {
+		err := s.Serve(l)
+		if err != nil && err != ErrServerClosed {
+			t.Fatal(err)
+		}
+	}()
+
+	clientDoneChan := make(chan struct{})
+	closeDoneChan := make(chan struct{})
+
+	sess, _, cleanup := newClientSession(t, l.Addr().String(), nil)
+	go func() {
+		defer cleanup()
+		defer close(clientDoneChan)
+		<-closeDoneChan
+		if err := sess.Run(""); err != nil && err != io.EOF {
+			t.Fatal(err)
+		}
+	}()
+
+	go func() {
+		err := s.Close()
+		if err != nil {
+			t.Fatal(err)
+		}
+		close(closeDoneChan)
+	}()
+
+	timeout := time.After(100 * time.Millisecond)
+	select {
+	case <-timeout:
+		t.Error("timeout")
+		return
+	case <-s.getDoneChan():
+		<-clientDoneChan
+		return
+	}
+}