| 1 | package host |
| 2 | |
| 3 | import ( |
| 4 | "bytes" |
| 5 | "crypto/sha256" |
| 6 | "encoding/hex" |
| 7 | "encoding/json" |
| 8 | "io" |
| 9 | "os" |
| 10 | "path/filepath" |
| 11 | "slices" |
| 12 | "strings" |
| 13 | |
| 14 | "github.com/carlosframework/platform/internal/hostbox" |
| 15 | "github.com/carlosframework/platform/internal/instancectl" |
| 16 | "github.com/carlosframework/platform/internal/provision" |
| 17 | "github.com/carlosframework/platform/internal/rootstate" |
| 18 | ) |
| 19 | |
| 20 | type claimUnitProgram struct { |
| 21 | Schema int |
| 22 | Host string |
| 23 | Args, Env []string |
| 24 | } |
| 25 | |
| 26 | func readClaimUnitProgram(shape claimUnitShape) (claimUnitProgram, error) { |
| 27 | if !provision.ValidHostShape(shape.Host) { |
| 28 | return claimUnitProgram{}, os.ErrPermission |
| 29 | } |
| 30 | f, err := rootstate.OpenAuthorityFile(filepath.Join("/etc/carlos/claim-units", shape.Host+".json")) |
| 31 | if err != nil { |
| 32 | return claimUnitProgram{}, err |
| 33 | } |
| 34 | defer f.Close() |
| 35 | raw, err := io.ReadAll(io.LimitReader(f, rootstate.MaxRecord+1)) |
| 36 | if err != nil { |
| 37 | return claimUnitProgram{}, err |
| 38 | } |
| 39 | return decodeClaimUnitProgram(raw, shape) |
| 40 | } |
| 41 | |
| 42 | func decodeClaimUnitProgram(raw []byte, shape claimUnitShape) (claimUnitProgram, error) { |
| 43 | var p claimUnitProgram |
| 44 | sum := sha256.Sum256(raw) |
| 45 | dec := json.NewDecoder(bytes.NewReader(raw)) |
| 46 | dec.DisallowUnknownFields() |
| 47 | if len(raw) > rootstate.MaxRecord || hex.EncodeToString(sum[:]) != shape.Program || dec.Decode(&p) != nil || dec.Decode(new(any)) != io.EOF || p.Schema != 1 || p.Host != shape.Host || len(p.Args) > 256 || len(p.Env) > 1024 { |
| 48 | return p, os.ErrPermission |
| 49 | } |
| 50 | for _, arg := range p.Args { |
| 51 | if strings.ContainsRune(arg, 0) { |
| 52 | return p, os.ErrPermission |
| 53 | } |
| 54 | } |
| 55 | seen := map[string]bool{} |
| 56 | for _, env := range p.Env { |
| 57 | key, _, ok := strings.Cut(env, "=") |
| 58 | if !ok || key == "" || strings.ContainsRune(env, 0) || seen[key] { |
| 59 | return p, os.ErrPermission |
| 60 | } |
| 61 | seen[key] = true |
| 62 | } |
| 63 | return p, nil |
| 64 | } |
| 65 | |
| 66 | func (h *ClaimLaunchRoot) boundLaunchSpec(q hostbox.RoleLaunchRequest) (instancectl.Launch, bool, error) { |
| 67 | var launch instancectl.Launch |
| 68 | host := q.Reservation.Target.Host |
| 69 | unit, _, err := claimLaunchPlacement(h.Units, host) |
| 70 | if err != nil { |
| 71 | return launch, false, err |
| 72 | } |
| 73 | if unit == instancectl.UnitName(instancectl.RoleRun, host) { |
| 74 | return launch, false, nil |
| 75 | } |
| 76 | if h.unitBindings == nil { |
| 77 | return launch, true, os.ErrPermission |
| 78 | } |
| 79 | b, err := h.unitBindings.read(host) |
| 80 | if err != nil { |
| 81 | return launch, true, err |
| 82 | } |
| 83 | // Older bindings only describe placement and retain the ordinary isolated |
| 84 | // launch contract. Production configuration requires a program digest. |
| 85 | if b.Shape.Program == "" { |
| 86 | return launch, false, nil |
| 87 | } |
| 88 | if b.Retiring || b.Retired || b.Shape.Unit != unit || h.unitProgram == nil { |
| 89 | return launch, true, os.ErrPermission |
| 90 | } |
| 91 | p, err := h.unitProgram(b.Shape) |
| 92 | if err != nil { |
| 93 | return launch, true, err |
| 94 | } |
| 95 | if q.Spec.Identity.Config != b.Shape.Program || !slices.Equal(p.Args, q.Spec.Args) || !slices.Equal(p.Env, q.Spec.Env) { |
| 96 | return launch, true, os.ErrPermission |
| 97 | } |
| 98 | return instancectl.Launch{Schema: instancectl.LaunchSchema, Host: host, Argv: append([]string{filepath.Join(instancectl.LiveDir, host)}, p.Args...), Env: append([]string(nil), p.Env...)}, true, nil |
| 99 | } |
| 100 | |
amadan