| 1 | package hostactors |
| 2 | |
| 3 | import ( |
| 4 | "bytes" |
| 5 | "context" |
| 6 | "crypto/ed25519" |
| 7 | "encoding/json" |
| 8 | "math" |
| 9 | "time" |
| 10 | |
| 11 | "github.com/carlosframework/platform/internal/hostfloor" |
| 12 | "github.com/carlosframework/platform/internal/release" |
| 13 | ) |
| 14 | |
| 15 | // CensusKeyBinding is approved by the root enrollment coordinator after its |
| 16 | // authenticated box session supplies a proof of possession. It is not an |
| 17 | // unauthenticated enrollment request or a console-generated box report. |
| 18 | type CensusKeyBinding struct { |
| 19 | Bucket string `json:"bucket"` |
| 20 | Box string `json:"box"` |
| 21 | Enrollment string `json:"enrollment"` |
| 22 | PublicKey ed25519.PublicKey `json:"public_key"` |
| 23 | } |
| 24 | |
| 25 | func (d Directory) BindCensusKey(ctx context.Context, signer release.Signer, before Observed, binding CensusKeyBinding, proof []byte) (Observed, error) { |
| 26 | // This write bypasses Replace's membership gate, so it decides against |
| 27 | // the signed roster at the caller's ETag, never a caller-supplied copy. |
| 28 | fresh, err := d.Read(ctx) |
| 29 | if err != nil { |
| 30 | return Observed{}, err |
| 31 | } |
| 32 | if before.ETag == "" || fresh.ETag != before.ETag { |
| 33 | return Observed{}, ErrRoster |
| 34 | } |
| 35 | before = fresh |
| 36 | b, ok := before.Roster.Boxes[binding.Box] |
| 37 | if !ok || binding.Bucket != d.Bucket || binding.Enrollment != b.Enrollment || len(binding.PublicKey) != ed25519.PublicKeySize || before.Roster.Revision == math.MaxUint64 { |
| 38 | return Observed{}, ErrRoster |
| 39 | } |
| 40 | raw, err := json.Marshal(binding) |
| 41 | if err != nil { |
| 42 | return Observed{}, err |
| 43 | } |
| 44 | if !ed25519.Verify(binding.PublicKey, raw, proof) { |
| 45 | return Observed{}, ErrRoster |
| 46 | } |
| 47 | // I2: binaries older than census_public_key refuse the strict-decoded |
| 48 | // roster once a key is bound, so binding waits for the published floor |
| 49 | // that excludes them. Only an active, unfenced enrollment is bound. |
| 50 | if before.Roster.Publication != "published" || b.State != "active" { |
| 51 | return Observed{}, ErrRoster |
| 52 | } |
| 53 | floor, err := hostfloor.Read(ctx, d.Store, d.PublicKey, d.Bucket) |
| 54 | if err != nil { |
| 55 | return Observed{}, err |
| 56 | } |
| 57 | if floor.Digest != before.Roster.FloorSHA256 { |
| 58 | return Observed{}, ErrRoster |
| 59 | } |
| 60 | fenced, err := d.TerminationFence(ctx, before, binding.Box, time.Now()) |
| 61 | if err != nil { |
| 62 | return Observed{}, err |
| 63 | } |
| 64 | if fenced { |
| 65 | return Observed{}, ErrRoster |
| 66 | } |
| 67 | if len(b.CensusPublicKey) != 0 { |
| 68 | if bytes.Equal(b.CensusPublicKey, binding.PublicKey) { |
| 69 | return before, nil |
| 70 | } |
| 71 | return Observed{}, ErrRoster |
| 72 | } |
| 73 | // One write-once extension to an existing enrollment. Ordinary Replace |
| 74 | // continues to reject changes to this field, including deletion/rotation. |
| 75 | next := Clone(before.Roster) |
| 76 | b.CensusPublicKey = append(ed25519.PublicKey(nil), binding.PublicKey...) |
| 77 | next.Boxes[binding.Box] = b |
| 78 | next.Revision++ |
| 79 | if err = next.Validate(d.Bucket); err != nil { |
| 80 | return Observed{}, err |
| 81 | } |
| 82 | wire, err := release.SignRootEnvelope(signer, next) |
| 83 | if err != nil { |
| 84 | return Observed{}, err |
| 85 | } |
| 86 | tag, err := d.Store.Put(ctx, Key, wire, before.ETag) |
| 87 | if err != nil { |
| 88 | return Observed{}, err |
| 89 | } |
| 90 | return Observed{Roster: next, ETag: tag}, nil |
| 91 | } |
| 92 | |
amadan