| 1 | //go:build linux |
| 2 | |
| 3 | package host |
| 4 | |
| 5 | import ( |
| 6 | "fmt" |
| 7 | "os" |
| 8 | "path/filepath" |
| 9 | "strings" |
| 10 | |
| 11 | "github.com/carlosframework/platform/internal/hostbox" |
| 12 | "golang.org/x/sys/unix" |
| 13 | ) |
| 14 | |
| 15 | // Resolve the filesystem's kernel device, then its containing disk if it is a |
| 16 | // partition. Only an EBS NVMe controller serial supplies independent identity; |
| 17 | // filesystem UUIDs and loop backing files cannot distinguish snapshot clones. |
| 18 | func servingParkVolume(device uint64) string { |
| 19 | return servingParkVolumeAt("/sys", device) |
| 20 | } |
| 21 | |
| 22 | func servingParkVolumeAt(sys string, device uint64) string { |
| 23 | path, err := filepath.EvalSymlinks(filepath.Join(sys, "dev", "block", fmt.Sprintf("%d:%d", unix.Major(device), unix.Minor(device)))) |
| 24 | if err != nil { |
| 25 | return "" |
| 26 | } |
| 27 | if _, err := os.Stat(filepath.Join(path, "partition")); err == nil { |
| 28 | path = filepath.Dir(path) |
| 29 | } else if !os.IsNotExist(err) { |
| 30 | return "" |
| 31 | } |
| 32 | raw, err := os.ReadFile(filepath.Join(path, "device", "serial")) |
| 33 | if err != nil { |
| 34 | return "" |
| 35 | } |
| 36 | serial := strings.TrimSpace(string(raw)) |
| 37 | if !strings.HasPrefix(serial, "vol") { |
| 38 | return "" |
| 39 | } |
| 40 | id := strings.TrimPrefix(strings.TrimPrefix(serial, "vol"), "-") |
| 41 | if len(id) != 8 && len(id) != 17 { |
| 42 | return "" |
| 43 | } |
| 44 | for _, c := range id { |
| 45 | if !(c >= '0' && c <= '9' || c >= 'a' && c <= 'f') { |
| 46 | return "" |
| 47 | } |
| 48 | } |
| 49 | return "vol" + id |
| 50 | } |
| 51 | |
| 52 | // A reboot binding grants recovery but never supplies missing volume evidence. |
| 53 | // Check again at deletion so a subsequent reboot or remount cannot borrow it. |
| 54 | func (f *servingParkFS) checkReapVolume(r *servingParkRecord) error { |
| 55 | b, err := servingParkReadBinding(f.state, "retirement-"+r.Authorization.ID) |
| 56 | if err != nil { |
| 57 | return err |
| 58 | } |
| 59 | if b == nil { |
| 60 | return nil |
| 61 | } |
| 62 | if f.volume == nil || b.Volume == "" || b.Volume != r.Source.Volume || f.volume(r.Source.Parent.Device) != r.Source.Volume { |
| 63 | return hostbox.ErrChanged |
| 64 | } |
| 65 | return f.checkBoot(b.BootID) |
| 66 | } |
| 67 | |
amadan