// Copyright (c) 2021 Tailscale Inc & AUTHORS All rights reserved. // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. // +build linux package vms import ( "crypto/sha256" "encoding/hex" "errors" "fmt" "io" "net" "net/http" "os" "os/exec" "path/filepath" "strconv" "strings" "syscall" "testing" "time" "github.com/aws/aws-sdk-go/aws" "github.com/aws/aws-sdk-go/aws/session" "github.com/aws/aws-sdk-go/service/s3" "github.com/aws/aws-sdk-go/service/s3/s3manager" "github.com/pkg/sftp" "golang.org/x/crypto/ssh" "tailscale.com/types/logger" ) // mkVM makes a KVM-accelerated virtual machine and prepares it for introduction // to the testcontrol server. The function it returns is for killing the virtual // machine when it is time for it to die. func (h *Harness) mkVM(t *testing.T, n int, d Distro, sshKey, hostURL, tdir string) { t.Helper() cdir, err := os.UserCacheDir() if err != nil { t.Fatalf("can't find cache dir: %v", err) } cdir = filepath.Join(cdir, "tailscale", "vm-test") os.MkdirAll(filepath.Join(cdir, "qcow2"), 0755) port, err := getProbablyFreePortNumber() if err != nil { t.Fatal(err) } mkLayeredQcow(t, tdir, d, h.fetchDistro(t, d)) mkSeed(t, d, sshKey, hostURL, tdir, port) driveArg := fmt.Sprintf("file=%s,if=virtio", filepath.Join(tdir, d.Name+".qcow2")) args := []string{ "-machine", "pc-q35-5.1,accel=kvm,usb=off,vmport=off,dump-guest-core=off", "-netdev", fmt.Sprintf("user,hostfwd=::%d-:22,id=net0", port), "-device", "virtio-net-pci,netdev=net0,id=net0,mac=8a:28:5c:30:1f:25", "-m", fmt.Sprint(d.MemoryMegs), "-boot", "c", "-drive", driveArg, "-cdrom", filepath.Join(tdir, d.Name, "seed", "seed.iso"), "-smbios", "type=1,serial=ds=nocloud;h=" + d.Name, } if *useVNC { // test listening on VNC port ln, err := net.Listen("tcp", net.JoinHostPort("0.0.0.0", strconv.Itoa(5900+n))) if err != nil { t.Fatalf("would not be able to listen on the VNC port for the VM: %v", err) } ln.Close() args = append(args, "-vnc", fmt.Sprintf(":%d", n)) } else { args = append(args, "-display", "none") } t.Logf("running: qemu-system-x86_64 %s", strings.Join(args, " ")) cmd := exec.Command("qemu-system-x86_64", args...) cmd.Stdout = logger.FuncWriter(t.Logf) cmd.Stderr = logger.FuncWriter(t.Logf) err = cmd.Start() if err != nil { t.Fatal(err) } time.Sleep(time.Second) // NOTE(Xe): In Unix if you do a kill with signal number 0, the kernel will do // all of the access checking for the process (existence, permissions, etc) but // nothing else. This is a way to ensure that qemu's process is active. if err := cmd.Process.Signal(syscall.Signal(0)); err != nil { t.Fatalf("qemu is not running: %v", err) } t.Cleanup(func() { err := cmd.Process.Kill() if err != nil { t.Errorf("can't kill %s (%d): %v", d.Name, cmd.Process.Pid, err) } cmd.Wait() }) } // fetchFromS3 fetches a distribution image from Amazon S3 or reports whether // it is unable to. It can fail to fetch from S3 if there is either no AWS // configuration (in ~/.aws/credentials) or if the `-no-s3` flag is passed. In // that case the test will fall back to downloading distribution images from the // public internet. // // Like fetching from HTTP, the test will fail if an error is encountered during // the downloading process. // // This function writes the distribution image to fout. It is always closed. Do // not expect fout to remain writable. func fetchFromS3(t *testing.T, fout *os.File, d Distro) bool { t.Helper() if *noS3 { t.Log("you asked to not use S3, not using S3") return false } sess, err := session.NewSession(&aws.Config{ Region: aws.String("us-east-1"), }) if err != nil { t.Logf("can't make AWS session: %v", err) return false } dler := s3manager.NewDownloader(sess, func(d *s3manager.Downloader) { d.PartSize = 64 * 1024 * 1024 // 64MB per part }) t.Logf("fetching s3://%s/%s", bucketName, d.SHA256Sum) _, err = dler.Download(fout, &s3.GetObjectInput{ Bucket: aws.String(bucketName), Key: aws.String(d.SHA256Sum), }) if err != nil { fout.Close() t.Fatalf("can't get s3://%s/%s: %v", bucketName, d.SHA256Sum, err) } err = fout.Close() if err != nil { t.Fatalf("can't close fout: %v", err) } return true } // fetchDistro fetches a distribution from the internet if it doesn't already exist locally. It // also validates the sha256 sum from a known good hash. func (h *Harness) fetchDistro(t *testing.T, resultDistro Distro) string { t.Helper() cdir, err := os.UserCacheDir() if err != nil { t.Fatalf("can't find cache dir: %v", err) } cdir = filepath.Join(cdir, "tailscale", "vm-test") if strings.HasPrefix(resultDistro.Name, "nixos") { return h.makeNixOSImage(t, resultDistro, cdir) } qcowPath := filepath.Join(cdir, "qcow2", resultDistro.SHA256Sum) _, err = os.Stat(qcowPath) if err == nil { hash := checkCachedImageHash(t, resultDistro, cdir) if hash != resultDistro.SHA256Sum { t.Logf("hash for %s (%s) doesn't match expected %s, re-downloading", resultDistro.Name, qcowPath, resultDistro.SHA256Sum) err = errors.New("some fake non-nil error to force a redownload") if err := os.Remove(qcowPath); err != nil { t.Fatalf("can't delete wrong cached image: %v", err) } } } if err != nil { t.Logf("downloading distro image %s to %s", resultDistro.URL, qcowPath) fout, err := os.Create(qcowPath) if err != nil { t.Fatal(err) } if !fetchFromS3(t, fout, resultDistro) { resp, err := http.Get(resultDistro.URL) if err != nil { t.Fatalf("can't fetch qcow2 for %s (%s): %v", resultDistro.Name, resultDistro.URL, err) } if resp.StatusCode != http.StatusOK { resp.Body.Close() t.Fatalf("%s replied %s", resultDistro.URL, resp.Status) } _, err = io.Copy(fout, resp.Body) if err != nil { t.Fatalf("download of %s failed: %v", resultDistro.URL, err) } resp.Body.Close() err = fout.Close() if err != nil { t.Fatalf("can't close fout: %v", err) } hash := checkCachedImageHash(t, resultDistro, cdir) if hash != resultDistro.SHA256Sum { t.Fatalf("hash mismatch, want: %s, got: %s", resultDistro.SHA256Sum, hash) } } } return qcowPath } func checkCachedImageHash(t *testing.T, d Distro, cacheDir string) (gotHash string) { t.Helper() qcowPath := filepath.Join(cacheDir, "qcow2", d.SHA256Sum) fin, err := os.Open(qcowPath) if err != nil { t.Fatal(err) } hasher := sha256.New() if _, err := io.Copy(hasher, fin); err != nil { t.Fatal(err) } hash := hex.EncodeToString(hasher.Sum(nil)) if hash != d.SHA256Sum { t.Fatalf("hash mismatch, got: %q, want: %q", hash, d.SHA256Sum) } gotHash = hash return } func (h *Harness) copyBinaries(t *testing.T, d Distro, conn *ssh.Client) { bins := h.bins if strings.HasPrefix(d.Name, "nixos") { return } cli, err := sftp.NewClient(conn) if err != nil { t.Fatalf("can't connect over sftp to copy binaries: %v", err) } mkdir(t, cli, "/usr/bin") mkdir(t, cli, "/usr/sbin") mkdir(t, cli, "/etc/default") mkdir(t, cli, "/var/lib/tailscale") copyFile(t, cli, bins.Daemon, "/usr/sbin/tailscaled") copyFile(t, cli, bins.CLI, "/usr/bin/tailscale") // TODO(Xe): revisit this assumption before it breaks the test. copyFile(t, cli, "../../../cmd/tailscaled/tailscaled.defaults", "/etc/default/tailscaled") switch d.InitSystem { case "openrc": mkdir(t, cli, "/etc/init.d") copyFile(t, cli, "../../../cmd/tailscaled/tailscaled.openrc", "/etc/init.d/tailscaled") case "systemd": mkdir(t, cli, "/etc/systemd/system") copyFile(t, cli, "../../../cmd/tailscaled/tailscaled.service", "/etc/systemd/system/tailscaled.service") } fout, err := cli.OpenFile("/etc/default/tailscaled", os.O_WRONLY|os.O_APPEND) if err != nil { t.Fatalf("can't append to defaults for tailscaled: %v", err) } fmt.Fprintf(fout, "\n\nTS_LOG_TARGET=%s\n", h.loginServerURL) fout.Close() t.Log("tailscale installed!") } func mkdir(t *testing.T, cli *sftp.Client, name string) { t.Helper() err := cli.MkdirAll(name) if err != nil { t.Fatalf("can't make %s: %v", name, err) } } func copyFile(t *testing.T, cli *sftp.Client, localSrc, remoteDest string) { t.Helper() fin, err := os.Open(localSrc) if err != nil { t.Fatalf("can't open: %v", err) } defer fin.Close() fi, err := fin.Stat() if err != nil { t.Fatalf("can't stat: %v", err) } fout, err := cli.Create(remoteDest) if err != nil { t.Fatalf("can't create output file: %v", err) } err = fout.Chmod(fi.Mode()) if err != nil { fout.Close() t.Fatalf("can't chmod fout: %v", err) } n, err := io.Copy(fout, fin) if err != nil { fout.Close() t.Fatalf("copy failed: %v", err) } if fi.Size() != n { t.Fatalf("incorrect number of bytes copied: wanted: %d, got: %d", fi.Size(), n) } err = fout.Close() if err != nil { t.Fatalf("can't close fout on remote host: %v", err) } } const metaDataTemplate = `instance-id: {{.ID}} local-hostname: {{.Hostname}}` const userDataTemplate = `#cloud-config #vim:syntax=yaml cloud_config_modules: - runcmd cloud_final_modules: - [users-groups, always] - [scripts-user, once-per-instance] users: - name: root ssh-authorized-keys: - {{.SSHKey}} - name: ts plain_text_passwd: {{.Password}} groups: [ wheel ] sudo: [ "ALL=(ALL) NOPASSWD:ALL" ] shell: /bin/sh ssh-authorized-keys: - {{.SSHKey}} write_files: - path: /etc/cloud/cloud.cfg.d/80_disable_network_after_firstboot.cfg content: | # Disable network configuration after first boot network: config: disabled runcmd: {{.InstallPre}} - [ curl, "{{.HostURL}}/myip/{{.Port}}", "-H", "User-Agent: {{.Hostname}}" ] `