| 1 | package release |
| 2 | |
| 3 | import ( |
| 4 | "context" |
| 5 | "crypto/ed25519" |
| 6 | "crypto/sha256" |
| 7 | "errors" |
| 8 | "fmt" |
| 9 | "strings" |
| 10 | "time" |
| 11 | ) |
| 12 | |
| 13 | // ManifestDigest is the sha256 of a manifest's canonical bytes: exactly what |
| 14 | // the store holds at ManifestKey, never a re-marshal (#253, spec §4.6). The |
| 15 | // manifest carries every artifact's sha256, so this one digest binds the |
| 16 | // bytes a box will stage. |
| 17 | func ManifestDigest(raw []byte) string { return etagOf(raw) } |
| 18 | |
| 19 | // ErrManifestDigest is a manifest whose bytes do not hash to the digest a |
| 20 | // signed pointer (or, from plan 2, a promotion record) recorded for it: a |
| 21 | // version name reused with other bytes, or a swapped object. |
| 22 | var ErrManifestDigest = errors.New("release: manifest does not hash to the digest its signer recorded") |
| 23 | |
| 24 | // CheckManifestDigest reads version's canonical manifest and, when want is |
| 25 | // set, refuses it unless its bytes hash to want. The manifest and bytes it |
| 26 | // returns are the ones it checked: a caller must stage from these and never |
| 27 | // re-read the manifest, or a swap between the check and the read would slip |
| 28 | // through. want "" is today's read, unchecked. |
| 29 | func CheckManifestDigest(ctx context.Context, s Store, acct, app, version, want string) (*Manifest, []byte, error) { |
| 30 | m, raw, err := GetManifestRaw(ctx, s, acct, app, version) |
| 31 | if err != nil { |
| 32 | return nil, nil, err |
| 33 | } |
| 34 | if want != "" { |
| 35 | if got := ManifestDigest(raw); got != want { |
| 36 | return nil, nil, fmt.Errorf("%w: %s/%s hashes to %s, the pointer signed %s", |
| 37 | ErrManifestDigest, app, version, digestShort(got), digestShort(want)) |
| 38 | } |
| 39 | } |
| 40 | return m, raw, nil |
| 41 | } |
| 42 | |
| 43 | // validDigest is the one shape a digest may take: 64 lowercase hex. |
| 44 | func validDigest(d string) bool { |
| 45 | if len(d) != 2*sha256.Size { |
| 46 | return false |
| 47 | } |
| 48 | for _, c := range d { |
| 49 | if !(c >= '0' && c <= '9' || c >= 'a' && c <= 'f') { |
| 50 | return false |
| 51 | } |
| 52 | } |
| 53 | return true |
| 54 | } |
| 55 | |
| 56 | // digestShort is a digest as a person reads it in a log line. |
| 57 | func digestShort(d string) string { |
| 58 | if len(d) > 12 { |
| 59 | return d[:12] |
| 60 | } |
| 61 | return d |
| 62 | } |
| 63 | |
| 64 | // DigestOf is the signed digest of version as this pointer names it: the |
| 65 | // head's when version is the head, else the History entry's. "" when the |
| 66 | // pointer signs none for it, or does not name it. |
| 67 | func (p *ChannelPointer) DigestOf(version string) string { |
| 68 | if p == nil { |
| 69 | return "" |
| 70 | } |
| 71 | if version == p.Version { |
| 72 | return p.Digest |
| 73 | } |
| 74 | for i, v := range p.History { |
| 75 | if v == version && i < len(p.HistoryDigests) { |
| 76 | return p.HistoryDigests[i] |
| 77 | } |
| 78 | } |
| 79 | return "" |
| 80 | } |
| 81 | |
| 82 | // CarriesDigests is the test the ratchet and CARLOS_REQUIRE_POINTER_DIGEST |
| 83 | // apply: a pointer "with digests" signs one for its head. |
| 84 | func (p *ChannelPointer) CarriesDigests() bool { return p != nil && p.Digest != "" } |
| 85 | |
| 86 | // ChannelHasDigests reports whether any entry carries a digest: the rollback |
| 87 | // rule's test (spec §4.6, "once its channel has any digest"). |
| 88 | func (p *ChannelPointer) ChannelHasDigests() bool { |
| 89 | if p == nil { |
| 90 | return false |
| 91 | } |
| 92 | if p.CarriesDigests() { |
| 93 | return true |
| 94 | } |
| 95 | for _, d := range p.HistoryDigests { |
| 96 | if d != "" { |
| 97 | return true |
| 98 | } |
| 99 | } |
| 100 | return false |
| 101 | } |
| 102 | |
| 103 | // alignedHistoryDigests is p.HistoryDigests at History's length: an absent |
| 104 | // list is all "". The copy is the writer's to change. |
| 105 | func alignedHistoryDigests(p *ChannelPointer) []string { |
| 106 | out := make([]string, len(p.History)) |
| 107 | copy(out, p.HistoryDigests) |
| 108 | return out |
| 109 | } |
| 110 | |
| 111 | // inheritedDigests is the history half of the provenance rule for a write |
| 112 | // that moves the head to version: each entry's digest copied verbatim from |
| 113 | // the verified predecessor, aligned with the History the write builds, and |
| 114 | // never computed (spec §4.6). Its length always equals that History's. |
| 115 | func inheritedDigests(old *ChannelPointer, version string) []string { |
| 116 | hd := alignedHistoryDigests(old) |
| 117 | if old.Version != "" && old.Version != version { |
| 118 | hd = prependCapped(old.Digest, hd, historyMax) |
| 119 | } |
| 120 | return hd |
| 121 | } |
| 122 | |
| 123 | // ResignNeededError is a move onto a history entry that carries no digest, on |
| 124 | // a channel that carries some (spec §4.6): a rollback, or a promote of a build |
| 125 | // already in the channel's history. |
| 126 | type ResignNeededError struct{ App, Channel, Version string } |
| 127 | |
| 128 | func (e *ResignNeededError) Error() string { |
| 129 | return fmt.Sprintf(TextRollbackResign, e.App, e.Channel, e.Version, e.App, e.Channel) |
| 130 | } |
| 131 | |
| 132 | // ChannelDigestState is one channel's line in the straggler report (spec |
| 133 | // §4.6 "Watch for stragglers"). Err set means the channel's pointer could not |
| 134 | // be read or verified: its digest state is unknown, and every other field is |
| 135 | // zero. A report with such a line is incomplete, so it never says the fleet |
| 136 | // is ready for CARLOS_REQUIRE_POINTER_DIGEST (Astra r1 #4). |
| 137 | type ChannelDigestState struct { |
| 138 | Channel string `json:"channel"` |
| 139 | Version string `json:"version"` |
| 140 | PromotedAt time.Time `json:"promoted_at"` |
| 141 | HeadDigest bool `json:"head_digest"` |
| 142 | HistoryMissing int `json:"history_missing"` |
| 143 | Straggler bool `json:"straggler"` |
| 144 | Err string `json:"error,omitempty"` |
| 145 | } |
| 146 | |
| 147 | // DigestStateOf is a verified pointer's line. A straggler is a pointer |
| 148 | // without digests signed after the marker went on: an old writer is still in |
| 149 | // use. |
| 150 | func DigestStateOf(p *ChannelPointer, marker *DigestMarker) ChannelDigestState { |
| 151 | st := ChannelDigestState{Channel: p.Channel, Version: p.Version, PromotedAt: p.PromotedAt, HeadDigest: p.CarriesDigests()} |
| 152 | hd := alignedHistoryDigests(p) |
| 153 | for _, d := range hd { |
| 154 | if d == "" { |
| 155 | st.HistoryMissing++ |
| 156 | } |
| 157 | } |
| 158 | st.Straggler = marker != nil && !st.HeadDigest && p.PromotedAt.After(marker.At) |
| 159 | return st |
| 160 | } |
| 161 | |
| 162 | // DigestReport is every channel of one app, plus the account's marker. A |
| 163 | // pointer that cannot be read or does not verify is never skipped: it comes |
| 164 | // back as a line with Err set, its state unknown. |
| 165 | func DigestReport(ctx context.Context, s Store, pub ed25519.PublicKey, acct, app string) ([]ChannelDigestState, *DigestMarker, error) { |
| 166 | marker, err := ReadDigestMarker(ctx, s, pub, acct) |
| 167 | if err != nil { |
| 168 | return nil, nil, err |
| 169 | } |
| 170 | prefix := ChannelsPrefix(acct, app) |
| 171 | keys, err := s.List(ctx, prefix) |
| 172 | if err != nil { |
| 173 | return nil, nil, err |
| 174 | } |
| 175 | var out []ChannelDigestState |
| 176 | for _, k := range keys { |
| 177 | name, ok := strings.CutSuffix(strings.TrimPrefix(k, prefix), ".json") |
| 178 | if !ok || name == "" { |
| 179 | continue |
| 180 | } |
| 181 | p, err := Channel(ctx, s, pub, acct, app, name) |
| 182 | if err != nil { |
| 183 | out = append(out, ChannelDigestState{Channel: name, Err: fmt.Sprintf("%s: %v", ChannelKey(acct, app, name), err)}) |
| 184 | continue |
| 185 | } |
| 186 | out = append(out, DigestStateOf(p, marker)) |
| 187 | } |
| 188 | return out, marker, nil |
| 189 | } |
| 190 | |
amadan