Initial Backupper Unraid plugin

internal/platform/mounts.go

@@ -0,0 +1,101 @@
+package platform
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+
+	"github.com/backupper-unraid/backupper/internal/model"
+)
+
+type CredentialGetter interface{ Get(string) (string, error) }
+
+type MountManager struct {
+	RuntimeDir string
+	Secrets    CredentialGetter
+}
+
+type MountedRepository struct {
+	Repository     model.Repository
+	Mounted        bool
+	CredentialFile string
+}
+
+func (m *MountManager) Prepare(ctx context.Context, repo model.Repository) (MountedRepository, error) {
+	result := MountedRepository{Repository: repo}
+	if repo.Type != model.RepositorySMB && repo.Type != model.RepositoryNFS {
+		return result, nil
+	}
+	if repo.Mount == nil || !repo.Mount.Managed {
+		if _, err := os.Stat(repo.Location); err != nil {
+			return result, fmt.Errorf("connectivity: external mount unavailable: %w", err)
+		}
+		return result, nil
+	}
+	point := filepath.Clean(repo.Mount.MountPoint)
+	if !strings.HasPrefix(point, "/mnt/remotes/") && !strings.HasPrefix(point, "/mnt/disks/") {
+		return result, errors.New("validation: managed mountPoint must be below /mnt/remotes or /mnt/disks")
+	}
+	if err := os.MkdirAll(point, 0700); err != nil {
+		return result, err
+	}
+	mountType := string(repo.Type)
+	if repo.Type == model.RepositorySMB {
+		mountType = "cifs"
+	}
+	args := []string{"-t", mountType, repo.Mount.Remote, point}
+	if repo.Type == model.RepositorySMB {
+		options := []string{"nosuid", "nodev"}
+		if repo.CredentialRef != "" {
+			credential, err := m.Secrets.Get(repo.CredentialRef)
+			if err != nil {
+				return result, fmt.Errorf("authentication: load mount credential: %w", err)
+			}
+			dir := filepath.Join(m.RuntimeDir, "secrets")
+			if err := os.MkdirAll(dir, 0700); err != nil {
+				return result, err
+			}
+			f, err := os.CreateTemp(dir, "smb-credentials-*")
+			if err != nil {
+				return result, err
+			}
+			result.CredentialFile = f.Name()
+			if err := f.Chmod(0600); err != nil {
+				f.Close()
+				return result, err
+			}
+			if _, err := f.WriteString(credential); err != nil {
+				f.Close()
+				return result, err
+			}
+			if err := f.Close(); err != nil {
+				return result, err
+			}
+			options = append(options, "credentials="+result.CredentialFile)
+		}
+		args = append(args, "-o", strings.Join(options, ","))
+	} else {
+		args = append(args, "-o", "nosuid,nodev")
+	}
+	if err := exec.CommandContext(ctx, "mount", args...).Run(); err != nil {
+		m.Cleanup(context.Background(), result)
+		return result, fmt.Errorf("connectivity: mount repository: %w", err)
+	}
+	result.Mounted = true
+	result.Repository.Location = point
+	return result, nil
+}
+
+func (m *MountManager) Cleanup(ctx context.Context, mounted MountedRepository) error {
+	if mounted.CredentialFile != "" {
+		defer os.Remove(mounted.CredentialFile)
+	}
+	if !mounted.Mounted {
+		return nil
+	}
+	return exec.CommandContext(ctx, "umount", mounted.Repository.Location).Run()
+}