Restore working state

cmd/imgbuilder/builder/build.go

@@ -1,6 +1,7 @@
 package builder
 
 import (
+	"bytes"
 	"context"
 	"fmt"
 	"os"
@@ -13,6 +14,7 @@ import (
 
 	"log/slog"
 
+	"github.com/AlexSSD7/linsk/utils"
 	"github.com/AlexSSD7/linsk/vm"
 	"github.com/alessio/shellescape"
 	"github.com/pkg/errors"
@@ -176,6 +178,9 @@ func runAlpineSetupCmd(sc *ssh.Client, pkgs []string) error {
 
 	// TODO: Timeout for this command.
 
+	stderr := bytes.NewBuffer(nil)
+	sess.Stderr = stderr
+
 	defer func() {
 		_ = sess.Close()
 	}()
@@ -191,9 +196,11 @@ func runAlpineSetupCmd(sc *ssh.Client, pkgs []string) error {
 		cmd += " && mount /dev/vda3 /mnt && chroot /mnt apk add " + strings.Join(pkgsQuoted, " ")
 	}
 
+	cmd += `&& chroot /mnt ash -c 'echo "PasswordAuthentication no" >> /etc/ssh/sshd_config && addgroup -g 1000 linsk && adduser -G linsk linsk -S -u 1000'`
+
 	err = sess.Run(cmd)
 	if err != nil {
-		return errors.Wrap(err, "run setup cmd")
+		return utils.WrapErrWithLog(err, "run setup cmd", stderr.String())
 	}
 
 	return nil

cmd/utils.go

@@ -47,7 +47,10 @@ func runVM(passthroughArg string, fn func(context.Context, *vm.VM, *vm.FileManag
 	}
 
 	vmCfg := vm.VMConfig{
-		CdromImagePath: "alpine-img/alpine.qcow2",
+		Drives: []vm.DriveConfig{{
+			Path:         "alpine.qcow2",
+			SnapshotMode: true,
+		}},
 
 		USBDevices:               passthroughConfig,
 		ExtraPortForwardingRules: forwardPortsRules,
@@ -111,6 +114,10 @@ func runVM(passthroughArg string, fn func(context.Context, *vm.VM, *vm.FileManag
 	for {
 		select {
 		case err := <-runErrCh:
+			if err == nil {
+				err = fmt.Errorf("operation canceled by user")
+			}
+
 			slog.Error("Failed to start the VM", "error", err)
 			os.Exit(1)
 		case <-vi.SSHUpNotifyChan():

utils/errors.go

@@ -0,0 +1,26 @@
+package utils
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/pkg/errors"
+)
+
+func WrapErrWithLog(err error, msg, log string) error {
+	return errors.Wrapf(err, "%v %v", msg, GetLogErrMsg(log))
+}
+
+func GetLogErrMsg(s string) string {
+	logToInclude := strings.ReplaceAll(s, "\n", "\\n")
+	logToInclude = strings.TrimSuffix(logToInclude, "\\n")
+	logToInclude = ClearUnprintableChars(logToInclude, false)
+
+	origLogLen := len(logToInclude)
+	const maxLogLen = 256
+	if origLogLen > maxLogLen {
+		logToInclude = fmt.Sprintf("[%v chars trimmed]", origLogLen) + logToInclude[len(logToInclude)-maxLogLen:]
+	}
+
+	return fmt.Sprintf("(log: '%v')", logToInclude)
+}

vm/errors.go

@@ -1,31 +1,9 @@
 package vm
 
 import (
-	"fmt"
-	"strings"
-
-	"github.com/AlexSSD7/linsk/utils"
 	"github.com/pkg/errors"
 )
 
 var (
 	ErrSSHUnavailable = errors.New("ssh unavailable")
 )
-
-func wrapErrWithLog(err error, msg, log string) error {
-	return errors.Wrapf(err, "%v %v", msg, getLogErrMsg(log))
-}
-
-func getLogErrMsg(s string) string {
-	logToInclude := strings.ReplaceAll(s, "\n", "\\n")
-	logToInclude = strings.TrimSuffix(logToInclude, "\\n")
-	logToInclude = utils.ClearUnprintableChars(logToInclude, false)
-
-	origLogLen := len(logToInclude)
-	const maxLogLen = 256
-	if origLogLen > maxLogLen {
-		logToInclude = fmt.Sprintf("[%v chars trimmed]", origLogLen) + logToInclude[len(logToInclude)-maxLogLen:]
-	}
-
-	return fmt.Sprintf("(log: '%v')", logToInclude)
-}

vm/filemanager.go

@@ -141,7 +141,7 @@ func (fm *FileManager) luksOpen(sc *ssh.Client, fullDevPath string) error {
 
 	err = sess.Wait()
 	if err != nil {
-		return wrapErrWithLog(err, "wait for cryptsetup luksopen cmd to finish", stderrBuf.String())
+		return utils.WrapErrWithLog(err, "wait for cryptsetup luksopen cmd to finish", stderrBuf.String())
 	}
 
 	lg.Info("LUKS device opened successfully")
@@ -279,7 +279,7 @@ create mask = 0664`
 
 	err = sess.Wait()
 	if err != nil {
-		return wrapErrWithLog(err, "wait for change samba password cmd", stderr.String())
+		return utils.WrapErrWithLog(err, "wait for change samba password cmd", stderr.String())
 	}
 
 	return nil

vm/ssh.go

@@ -121,7 +121,7 @@ func (vm *VM) sshSetup() (ssh.Signer, error) {
 		case <-vm.ctx.Done():
 			return nil, vm.ctx.Err()
 		case <-time.After(time.Until(deadline)):
-			return nil, fmt.Errorf("setup command timed out %v", getLogErrMsg(stdOutErrBuf.String()))
+			return nil, fmt.Errorf("setup command timed out %v", utils.GetLogErrMsg(stdOutErrBuf.String()))
 		case data := <-vm.serialStdoutCh:
 			prefix := []byte("SERIAL STATUS: ")
 			stdOutErrBuf.WriteString(utils.ClearUnprintableChars(string(data), true))
@@ -132,7 +132,7 @@ func (vm *VM) sshSetup() (ssh.Signer, error) {
 
 				if data[len(prefix)] != '0' {
 					fmt.Fprintf(os.Stderr, "SSH SETUP FAILURE:\n%v", stdOutErrBuf.String())
-					return nil, fmt.Errorf("non-zero setup command status code: '%v' %v", string(data[len(prefix)]), getLogErrMsg(stdOutErrBuf.String()))
+					return nil, fmt.Errorf("non-zero setup command status code: '%v' %v", string(data[len(prefix)]), utils.GetLogErrMsg(stdOutErrBuf.String()))
 				}
 
 				return sshSigner, nil
@@ -173,7 +173,7 @@ func runSSHCmd(c *ssh.Client, cmd string) ([]byte, error) {
 
 	err = sess.Run(cmd)
 	if err != nil {
-		return nil, wrapErrWithLog(err, "run cmd", stderr.String())
+		return nil, utils.WrapErrWithLog(err, "run cmd", stderr.String())
 	}
 
 	return stdout.Bytes(), nil

vm/vm.go

@@ -18,6 +18,7 @@ import (
 
 	"log/slog"
 
+	"github.com/AlexSSD7/linsk/utils"
 	"github.com/alessio/shellescape"
 	"github.com/bramvdbogaerde/go-scp"
 	"github.com/phayes/freeport"
@@ -59,10 +60,10 @@ type DriveConfig struct {
 
 type VMConfig struct {
 	CdromImagePath string
+	Drives         []DriveConfig
 
 	USBDevices               []USBDevicePassthroughConfig
 	ExtraPortForwardingRules []PortForwardingRule
-	Drives                   []DriveConfig
 
 	// Mostly debug-related options.
 	UnrestrictedNetworking bool
@@ -126,13 +127,15 @@ func NewVM(logger *slog.Logger, cfg VMConfig) (*VM, error) {
 
 		driveArgs := "file=" + shellescape.Quote(extraDrive.Path) + ",format=qcow2,if=virtio"
 		if extraDrive.SnapshotMode {
-			driveArgs += ",snapshot"
+			driveArgs += ",snapshot=on"
 		}
 
 		cmdArgs = append(cmdArgs, "-drive", driveArgs)
 	}
 
-	if cdromImagePath != "" {
+	// We're not using clean `cdromImagePath` here because it is set to "."
+	// when the original string is empty.
+	if cfg.CdromImagePath != "" {
 		cmdArgs = append(cmdArgs, "-boot", "d", "-cdrom", cdromImagePath)
 	}
 
@@ -264,14 +267,14 @@ func (vm *VM) Run() error {
 			errors.Wrap(cancelErr, "cancel"),
 		)
 
-		return fmt.Errorf("%w %v", combinedErr, getLogErrMsg(vm.stderrBuf.String()))
+		return fmt.Errorf("%w %v", combinedErr, utils.GetLogErrMsg(vm.stderrBuf.String()))
 	}
 
 	combinedErr := multierr.Combine(
 		append(globalErrs, errors.Wrap(cancelErr, "cancel on exit"))...,
 	)
 	if combinedErr != nil {
-		return fmt.Errorf("%w %v", combinedErr, getLogErrMsg(vm.stderrBuf.String()))
+		return fmt.Errorf("%w %v", combinedErr, utils.GetLogErrMsg(vm.stderrBuf.String()))
 	}
 
 	return nil