| 1 | package edge |
| 2 | |
| 3 | import ( |
| 4 | "context" |
| 5 | "crypto/sha256" |
| 6 | "encoding/hex" |
| 7 | "encoding/json" |
| 8 | "errors" |
| 9 | "fmt" |
| 10 | "io" |
| 11 | "log" |
| 12 | "math/rand/v2" |
| 13 | "os" |
| 14 | "path/filepath" |
| 15 | "strings" |
| 16 | "sync" |
| 17 | "time" |
| 18 | |
| 19 | "github.com/carlosframework/platform/internal/geo" |
| 20 | "github.com/carlosframework/platform/internal/geoip" |
| 21 | "github.com/carlosframework/platform/internal/release" |
| 22 | ) |
| 23 | |
| 24 | // The GeoIP mirror (geoip spec §5): poll control/geoip/current.json, fetch |
| 25 | // the content-addressed blob it names into an immutable local generation, |
| 26 | // and hot-swap the edge's reader. genMu serialises everything that chooses, |
| 27 | // expires or deletes a generation (codex R3-1); network I/O stays outside it. |
| 28 | |
| 29 | var ( |
| 30 | // geoPointerReadTimeout bounds every pointer read on its own, so a |
| 31 | // slow store cannot stretch the off bound past interval+jitter+this |
| 32 | // (codex R9 on R8-2). |
| 33 | geoPointerReadTimeout = 30 * time.Second |
| 34 | geoMirrorInterval = 10 * time.Minute |
| 35 | geoMirrorJitter = time.Minute |
| 36 | geoMirrorDeadline = 10 * time.Minute |
| 37 | geoExpiryInterval = time.Minute |
| 38 | ) |
| 39 | |
| 40 | // geoCurrent is the shared local format (geoip.LocalCurrent), so the |
| 41 | // console's follower reads exactly what this mirror writes. |
| 42 | type geoCurrent = geoip.LocalCurrent |
| 43 | |
| 44 | type geoMirror struct { |
| 45 | store release.Store |
| 46 | dir string |
| 47 | sw *geo.Swappable |
| 48 | now func() time.Time |
| 49 | maxBytes int64 |
| 50 | |
| 51 | genMu sync.Mutex |
| 52 | loadedSHA string |
| 53 | loadedType string |
| 54 | loadedBuild time.Time |
| 55 | skipSHA map[string]string // sha -> why (rejected | expired); cleared whenever the observed pointer changes |
| 56 | pointerSHA string // the sha the last readable pointer named; "" for none |
| 57 | syncPending bool // the last `current` rename is not known durable |
| 58 | unsynced map[string]geoCurrent // every generation a crash could bring back while syncPending; kept until a sync succeeds or it expires |
| 59 | |
| 60 | // The alert's inputs (geoip spec §10.4). The pointer's metadata is |
| 61 | // kept after the reader is dropped, so an expired pointer still reads |
| 62 | // as expired by the clock before the console marks it (codex R11-1). |
| 63 | pointerPresent bool |
| 64 | pointerType string |
| 65 | pointerBuild time.Time |
| 66 | pointerMarked bool |
| 67 | wantSince time.Time // a live pointer has named a sha not loaded here since then |
| 68 | feedFailing bool |
| 69 | feedBox string |
| 70 | // pointerKnown and feedKnown are false until a read has succeeded or |
| 71 | // confirmed absence: until then the alert's reading is unknown (nil), |
| 72 | // so a restart cannot clear an alert the last process raised (code |
| 73 | // review R4-2). |
| 74 | pointerKnown bool |
| 75 | feedKnown bool |
| 76 | lastErr string // last poll's error category, "" when healthy |
| 77 | failingAt time.Time |
| 78 | lastFailLog time.Time |
| 79 | } |
| 80 | |
| 81 | func newGeoMirror(store release.Store, dir string, sw *geo.Swappable) *geoMirror { |
| 82 | return &geoMirror{store: store, dir: dir, sw: sw, now: time.Now, maxBytes: geoip.MaxBlobBytes, skipSHA: map[string]string{}} |
| 83 | } |
| 84 | |
| 85 | // GeoIPState is the heartbeat's view of this edge's GeoIP (spec §5.5). |
| 86 | type GeoIPState struct { |
| 87 | Mode string `json:"mode"` // mirror | tunnel | none |
| 88 | SHA256 string `json:"sha256,omitempty"` |
| 89 | Type string `json:"type,omitempty"` |
| 90 | Error string `json:"error,omitempty"` |
| 91 | } |
| 92 | |
| 93 | func (m *geoMirror) State() GeoIPState { |
| 94 | m.genMu.Lock() |
| 95 | defer m.genMu.Unlock() |
| 96 | return GeoIPState{Mode: "mirror", SHA256: m.loadedSHA, Type: m.loadedType, Error: m.lastErr} |
| 97 | } |
| 98 | |
| 99 | func (m *geoMirror) path(sha string) string { return filepath.Join(m.dir, sha+".mmdb") } |
| 100 | |
| 101 | // Boot installs the local generation `current` names, if any, without |
| 102 | // touching the bucket, and clears everything else (spec §5.3 "At boot"). |
| 103 | func (m *geoMirror) Boot() { |
| 104 | if err := os.MkdirAll(m.dir, 0o755); err != nil { |
| 105 | log.Printf("edge: geoip directory unusable; GeoIP stays off until it is: %v", err) |
| 106 | return |
| 107 | } |
| 108 | os.Chmod(m.dir, 0o755) |
| 109 | m.genMu.Lock() |
| 110 | defer m.genMu.Unlock() |
| 111 | cur, err := m.readCurrent() |
| 112 | keep := "" |
| 113 | switch { |
| 114 | case err != nil && !errors.Is(err, os.ErrNotExist): |
| 115 | log.Printf("edge: geoip local state unreadable; starting with no database") |
| 116 | os.Remove(filepath.Join(m.dir, "current")) |
| 117 | case cur.SHA256 == "": |
| 118 | case geoip.Expired(cur.DatabaseType, time.Unix(cur.BuildEpoch, 0), m.now()): |
| 119 | log.Printf("edge: geoip database %s expired (GeoLite2, 30 days after build) and was removed", short(cur.SHA256)) |
| 120 | m.writeCurrentLocked(geoCurrent{}) |
| 121 | default: |
| 122 | db, err := geo.OpenMMDBTrusted(m.path(cur.SHA256)) |
| 123 | if err != nil { |
| 124 | log.Printf("edge: geoip local generation %s unopenable; starting with no database", short(cur.SHA256)) |
| 125 | os.Remove(filepath.Join(m.dir, "current")) |
| 126 | break |
| 127 | } |
| 128 | m.sw.Swap(db) |
| 129 | m.loadedSHA, m.loadedType, m.loadedBuild = cur.SHA256, db.Source(), db.BuildEpoch() |
| 130 | keep = cur.SHA256 |
| 131 | log.Printf("edge: geoip database %s (%s, built %s) loaded", short(cur.SHA256), db.Source(), db.BuildEpoch().Format("2006-01-02")) |
| 132 | } |
| 133 | m.cleanLocked(keep, true) |
| 134 | } |
| 135 | |
| 136 | func short(sha string) string { |
| 137 | if len(sha) > 8 { |
| 138 | return sha[:8] |
| 139 | } |
| 140 | return sha |
| 141 | } |
| 142 | |
| 143 | func (m *geoMirror) readCurrent() (geoCurrent, error) { |
| 144 | var c geoCurrent |
| 145 | b, err := os.ReadFile(filepath.Join(m.dir, geoip.LocalCurrentFile)) |
| 146 | if err != nil { |
| 147 | return c, err |
| 148 | } |
| 149 | return geoip.ParseLocalCurrent(b) |
| 150 | } |
| 151 | |
| 152 | // writeCurrentLocked replaces `current` atomically: temp, fsync, rename, |
| 153 | // fsync the directory (spec §5.2). |
| 154 | func (m *geoMirror) writeCurrentLocked(c geoCurrent) error { |
| 155 | b, _ := json.Marshal(c) |
| 156 | tmp, err := os.CreateTemp(m.dir, ".current-*") |
| 157 | if err != nil { |
| 158 | return err |
| 159 | } |
| 160 | defer os.Remove(tmp.Name()) |
| 161 | if _, err := tmp.Write(b); err != nil { |
| 162 | tmp.Close() |
| 163 | return err |
| 164 | } |
| 165 | if err := tmp.Sync(); err != nil { |
| 166 | tmp.Close() |
| 167 | return err |
| 168 | } |
| 169 | if err := tmp.Close(); err != nil { |
| 170 | return err |
| 171 | } |
| 172 | if err := os.Chmod(tmp.Name(), 0o644); err != nil { |
| 173 | return err |
| 174 | } |
| 175 | if err := os.Rename(tmp.Name(), filepath.Join(m.dir, "current")); err != nil { |
| 176 | return err |
| 177 | } |
| 178 | // After the rename `current` already names the new generation, so a |
| 179 | // failed directory fsync must not make the caller delete it (plan review |
| 180 | // R1-4): it is logged, and the rename stands. But the rename is not |
| 181 | // durable either: a crash could bring back the PREVIOUS `current`, so |
| 182 | // m.syncPending tells install to keep the previous generation too until |
| 183 | // a later write is durable (code review R1-4). |
| 184 | if err := syncDirFn(m.dir); err != nil { |
| 185 | log.Printf("edge: geoip directory sync failed after selecting a generation; keeping the earlier ones until it succeeds") |
| 186 | m.syncPending = true |
| 187 | return nil |
| 188 | } |
| 189 | m.syncPending, m.unsynced = false, nil |
| 190 | return nil |
| 191 | } |
| 192 | |
| 193 | // syncDirFn is syncDir, a variable so a test can inject a failure. |
| 194 | var syncDirFn = syncDir |
| 195 | |
| 196 | func syncDir(dir string) error { |
| 197 | d, err := os.Open(dir) |
| 198 | if err != nil { |
| 199 | return err |
| 200 | } |
| 201 | defer d.Close() |
| 202 | return d.Sync() |
| 203 | } |
| 204 | |
| 205 | // cleanLocked deletes every generation but keep and every stray |
| 206 | // .current-*. Downloads (.incoming-*) are deleted only at boot: at any other |
| 207 | // time one may be in progress outside genMu, and unlinking it would break |
| 208 | // a replacement that an expiry tick happened to race (plan review R1-3). |
| 209 | func (m *geoMirror) cleanLocked(keep string, atBoot bool) { |
| 210 | m.cleanLockedKeeping(atBoot, keep) |
| 211 | } |
| 212 | |
| 213 | // cleanLockedKeeping is cleanLocked with any number of generations kept. |
| 214 | func (m *geoMirror) cleanLockedKeeping(atBoot bool, keep ...string) { |
| 215 | kept := map[string]bool{} |
| 216 | for _, k := range keep { |
| 217 | if k != "" { |
| 218 | kept[k+".mmdb"] = true |
| 219 | } |
| 220 | } |
| 221 | entries, _ := os.ReadDir(m.dir) |
| 222 | for _, e := range entries { |
| 223 | n := e.Name() |
| 224 | if n == "current" || kept[n] { |
| 225 | continue |
| 226 | } |
| 227 | if strings.HasSuffix(n, ".mmdb") || strings.HasPrefix(n, ".current-") || (atBoot && strings.HasPrefix(n, ".incoming-")) { |
| 228 | os.Remove(filepath.Join(m.dir, n)) |
| 229 | } |
| 230 | } |
| 231 | } |
| 232 | |
| 233 | // clearLocked turns GeoIP off on this box: empty current, nil reader, no |
| 234 | // generations. |
| 235 | func (m *geoMirror) clearLocked() { |
| 236 | if err := m.writeCurrentLocked(geoCurrent{}); err != nil { |
| 237 | os.Remove(filepath.Join(m.dir, "current")) |
| 238 | } |
| 239 | m.sw.Swap(nil) |
| 240 | m.loadedSHA, m.loadedType, m.loadedBuild = "", "", time.Time{} |
| 241 | m.cleanLocked("", false) |
| 242 | } |
| 243 | |
| 244 | // Poll is one pass (spec §5.3). The caller bounds ctx by geoMirrorDeadline. |
| 245 | func (m *geoMirror) Poll(ctx context.Context) error { return m.poll(ctx, true) } |
| 246 | |
| 247 | // poll is one pass; recheck allows ONE immediate re-run when a finished |
| 248 | // download turns out to be superseded, so an `off` or a newer publish that |
| 249 | // landed during a long download takes effect now, not a whole interval later |
| 250 | // (codex R8-2). |
| 251 | func (m *geoMirror) poll(ctx context.Context, recheck bool) error { |
| 252 | // The control-plane state (feed, pointer) is read whatever the local |
| 253 | // directory's health, so the alert sees a published database this box |
| 254 | // cannot install (code review R2-4). |
| 255 | m.readFeedStatus(ctx) |
| 256 | raw, err := m.readPointer(ctx) |
| 257 | var p geoip.Pointer |
| 258 | if err == nil { |
| 259 | p, err = geoip.ParsePointer(raw) |
| 260 | } |
| 261 | if errors.Is(err, os.ErrNotExist) || errors.Is(err, geoip.ErrUnknownVersion) { |
| 262 | // No pointer, or one this binary cannot read: GeoIP is off on this |
| 263 | // box (spec §3), never "keep what is loaded" (plan review R1-7). |
| 264 | m.genMu.Lock() |
| 265 | if m.loadedSHA != "" { |
| 266 | if errors.Is(err, geoip.ErrUnknownVersion) { |
| 267 | log.Printf("edge: geoip turned off; the published pointer has a version this binary cannot read") |
| 268 | } else { |
| 269 | log.Printf("edge: geoip turned off; no database published") |
| 270 | } |
| 271 | } |
| 272 | m.pointerSHA, m.skipSHA = "", map[string]string{} |
| 273 | m.pointerPresent, m.pointerType, m.pointerBuild, m.pointerMarked, m.wantSince = false, "", time.Time{}, false, time.Time{} |
| 274 | m.pointerKnown = true |
| 275 | m.clearLocked() |
| 276 | m.lastErr = "" |
| 277 | m.genMu.Unlock() |
| 278 | return nil |
| 279 | } |
| 280 | if raw == nil && err != nil { |
| 281 | return m.fail("pointer unreadable", err) |
| 282 | } |
| 283 | if err != nil { |
| 284 | return m.fail("pointer invalid", err) |
| 285 | } |
| 286 | m.genMu.Lock() |
| 287 | m.pointerPresent, m.pointerType, m.pointerBuild, m.pointerMarked = true, p.DatabaseType, p.Build(), p.Expired |
| 288 | m.pointerKnown = true |
| 289 | switch { |
| 290 | case p.Expired || geoip.Expired(p.DatabaseType, p.Build(), m.now()): |
| 291 | m.wantSince = time.Time{} |
| 292 | case p.SHA256 == m.loadedSHA: |
| 293 | m.wantSince = time.Time{} |
| 294 | case m.wantSince.IsZero(): |
| 295 | m.wantSince = m.now() |
| 296 | } |
| 297 | if p.SHA256 != m.pointerSHA { |
| 298 | // The pointer moved (to anything, including back to an sha seen |
| 299 | // before): every earlier rejection is void (plan review R1-8). |
| 300 | m.pointerSHA, m.skipSHA = p.SHA256, map[string]string{} |
| 301 | } |
| 302 | if p.Expired || geoip.Expired(p.DatabaseType, p.Build(), m.now()) { |
| 303 | if m.skipSHA[p.SHA256] != "expired" { |
| 304 | log.Printf("edge: geoip database %s expired (GeoLite2, 30 days after build) and was removed", short(p.SHA256)) |
| 305 | } |
| 306 | m.skipSHA[p.SHA256] = "expired" |
| 307 | m.clearLocked() |
| 308 | m.lastErr = "" |
| 309 | m.genMu.Unlock() |
| 310 | return nil |
| 311 | } |
| 312 | if p.SHA256 == m.loadedSHA { |
| 313 | m.lastErr = "" |
| 314 | if m.syncPending { |
| 315 | // The selection was never made durable: retry the sync, and once |
| 316 | // it lands the retained recovery copies can go (code review |
| 317 | // R10-2). |
| 318 | if err := syncDirFn(m.dir); err == nil { |
| 319 | m.syncPending, m.unsynced = false, nil |
| 320 | m.cleanLocked(m.loadedSHA, false) |
| 321 | } |
| 322 | } |
| 323 | m.genMu.Unlock() |
| 324 | return nil |
| 325 | } |
| 326 | if _, skip := m.skipSHA[p.SHA256]; skip { |
| 327 | m.genMu.Unlock() |
| 328 | return nil |
| 329 | } |
| 330 | m.genMu.Unlock() |
| 331 | |
| 332 | if err := os.MkdirAll(m.dir, 0o755); err != nil { |
| 333 | return m.fail("local directory unusable", err) |
| 334 | } |
| 335 | tmp, err := m.download(ctx, p) |
| 336 | if err == nil && !m.pointerStillNames(ctx, p.SHA256) { |
| 337 | os.Remove(tmp) |
| 338 | if recheck { |
| 339 | return m.poll(ctx, false) |
| 340 | } |
| 341 | return nil |
| 342 | } |
| 343 | if err != nil { |
| 344 | if errors.Is(err, errGeoDigest) || errors.Is(err, errGeoSize) { |
| 345 | m.genMu.Lock() |
| 346 | m.skipSHA[p.SHA256] = "rejected" |
| 347 | m.genMu.Unlock() |
| 348 | log.Printf("edge: geoip blob %s rejected: %v", short(p.SHA256), err) |
| 349 | } |
| 350 | return m.fail("blob unavailable", err) |
| 351 | } |
| 352 | return m.install(tmp, p) |
| 353 | } |
| 354 | |
| 355 | // downloadHook is a test seam: called after .incoming is created, before |
| 356 | // the body is copied, so a test can run an expiry tick mid-download. |
| 357 | var downloadHook func() |
| 358 | |
| 359 | // pointerStillNames re-reads the pointer after a download: only a |
| 360 | // candidate the pointer still selects (unexpired) may be installed. A read |
| 361 | // failure answers false, which defers the install to the next pass rather |
| 362 | // than installing something nobody has confirmed is still wanted. |
| 363 | func (m *geoMirror) pointerStillNames(ctx context.Context, sha string) bool { |
| 364 | raw, err := m.readPointer(ctx) |
| 365 | if err != nil { |
| 366 | return false |
| 367 | } |
| 368 | p, err := geoip.ParsePointer(raw) |
| 369 | return err == nil && p.SHA256 == sha && !p.Expired && !geoip.Expired(p.DatabaseType, p.Build(), m.now()) |
| 370 | } |
| 371 | |
| 372 | var ( |
| 373 | errGeoDigest = errors.New("digest mismatch") |
| 374 | errGeoSize = errors.New("size mismatch") |
| 375 | ) |
| 376 | |
| 377 | // download streams the blob to .incoming-<sha>, checks size and digest, |
| 378 | // fsyncs, and returns its path. Outside genMu. |
| 379 | func (m *geoMirror) download(ctx context.Context, p geoip.Pointer) (string, error) { |
| 380 | rc, _, err := release.OpenObject(ctx, m.store, p.Key) |
| 381 | if err != nil { |
| 382 | return "", err |
| 383 | } |
| 384 | defer rc.Close() |
| 385 | tmp := filepath.Join(m.dir, ".incoming-"+p.SHA256) |
| 386 | f, err := os.OpenFile(tmp, os.O_CREATE|os.O_TRUNC|os.O_WRONLY, 0o644) |
| 387 | if err != nil { |
| 388 | return "", err |
| 389 | } |
| 390 | limit := p.Size |
| 391 | if m.maxBytes < limit { |
| 392 | limit = m.maxBytes |
| 393 | } |
| 394 | if downloadHook != nil { |
| 395 | downloadHook() |
| 396 | } |
| 397 | h := sha256.New() |
| 398 | n, err := io.Copy(io.MultiWriter(f, h), io.LimitReader(rc, limit+1)) |
| 399 | if err == nil { |
| 400 | err = f.Sync() |
| 401 | } |
| 402 | if cerr := f.Close(); err == nil { |
| 403 | err = cerr |
| 404 | } |
| 405 | switch { |
| 406 | case err != nil: |
| 407 | os.Remove(tmp) |
| 408 | return "", err |
| 409 | case n > limit || n != p.Size: |
| 410 | // n > limit: the blob ran past the cap (the box's maxBytes may be |
| 411 | // below what the pointer claims), however the counts compare. |
| 412 | os.Remove(tmp) |
| 413 | return "", errGeoSize |
| 414 | case hex.EncodeToString(h.Sum(nil)) != p.SHA256: |
| 415 | os.Remove(tmp) |
| 416 | return "", errGeoDigest |
| 417 | } |
| 418 | return tmp, nil |
| 419 | } |
| 420 | |
| 421 | // install commits a verified download under genMu (spec §5.3 steps 3-5), |
| 422 | // re-checking expiry against the file's own metadata first. |
| 423 | func (m *geoMirror) install(tmp string, p geoip.Pointer) error { |
| 424 | m.genMu.Lock() |
| 425 | defer m.genMu.Unlock() |
| 426 | final := m.path(p.SHA256) |
| 427 | if err := os.Rename(tmp, final); err != nil { |
| 428 | os.Remove(tmp) |
| 429 | return m.failLocked("install failed", err) |
| 430 | } |
| 431 | syncDir(m.dir) |
| 432 | db, err := geo.OpenMMDBTrusted(final) |
| 433 | if err != nil { |
| 434 | m.removeGenerationLocked(p.SHA256) |
| 435 | m.skipSHA[p.SHA256] = "rejected" |
| 436 | log.Printf("edge: geoip blob %s rejected: unopenable", short(p.SHA256)) |
| 437 | return m.failLocked("blob unopenable", err) |
| 438 | } |
| 439 | if geoip.Expired(db.Source(), db.BuildEpoch(), m.now()) { |
| 440 | db.Close() |
| 441 | m.removeGenerationLocked(p.SHA256) |
| 442 | m.skipSHA[p.SHA256] = "expired" |
| 443 | log.Printf("edge: geoip database %s expired (GeoLite2, 30 days after build) and was removed", short(p.SHA256)) |
| 444 | return nil |
| 445 | } |
| 446 | if err := m.writeCurrentLocked(geoCurrent{SHA256: p.SHA256, DatabaseType: db.Source(), BuildEpoch: db.BuildEpoch().Unix()}); err != nil { |
| 447 | db.Close() |
| 448 | m.removeGenerationLocked(p.SHA256) |
| 449 | return m.failLocked("install failed", err) |
| 450 | } |
| 451 | prev := geoCurrent{SHA256: m.loadedSHA, DatabaseType: m.loadedType, BuildEpoch: m.loadedBuild.Unix()} |
| 452 | m.sw.Swap(db) |
| 453 | m.loadedSHA, m.loadedType, m.loadedBuild = p.SHA256, db.Source(), db.BuildEpoch() |
| 454 | if m.syncPending { |
| 455 | // Until a sync succeeds, any `current` since the last durable one |
| 456 | // could come back after a crash: keep every one of them (code |
| 457 | // review R2 on R1-4). |
| 458 | if m.unsynced == nil { |
| 459 | m.unsynced = map[string]geoCurrent{} |
| 460 | } |
| 461 | if prev.SHA256 != "" { |
| 462 | m.unsynced[prev.SHA256] = prev |
| 463 | } |
| 464 | keep := []string{p.SHA256} |
| 465 | for sha := range m.unsynced { |
| 466 | keep = append(keep, sha) |
| 467 | } |
| 468 | m.cleanLockedKeeping(false, keep...) |
| 469 | } else { |
| 470 | m.cleanLocked(p.SHA256, false) |
| 471 | } |
| 472 | m.lastErr, m.failingAt, m.wantSince = "", time.Time{}, time.Time{} |
| 473 | log.Printf("edge: geoip database %s (%s, built %s) loaded", short(p.SHA256), db.Source(), db.BuildEpoch().Format("2006-01-02")) |
| 474 | return nil |
| 475 | } |
| 476 | |
| 477 | // removeGenerationLocked deletes a failed install's file unless the same |
| 478 | // generation is one a crash could bring back (loaded, or kept while syncs |
| 479 | // fail): republishing a retained A must never delete A on an error path |
| 480 | // (code review R3 on R1-4). |
| 481 | func (m *geoMirror) removeGenerationLocked(sha string) { |
| 482 | if _, retained := m.unsynced[sha]; sha == m.loadedSHA || retained { |
| 483 | return |
| 484 | } |
| 485 | os.Remove(m.path(sha)) |
| 486 | } |
| 487 | |
| 488 | // ExpireTick is D1 on the loaded generation, under genMu, so it can only |
| 489 | // ever remove the generation that is current at that moment (codex R3-1). |
| 490 | func (m *geoMirror) ExpireTick() { |
| 491 | m.genMu.Lock() |
| 492 | defer m.genMu.Unlock() |
| 493 | // Retained recovery copies obey D1 too (code review R10-2): an expired |
| 494 | // GeoLite2 kept only in case a crash brings it back is destroyed. |
| 495 | for sha, g := range m.unsynced { |
| 496 | if geoip.Expired(g.DatabaseType, time.Unix(g.BuildEpoch, 0), m.now()) { |
| 497 | os.Remove(m.path(sha)) |
| 498 | delete(m.unsynced, sha) |
| 499 | } |
| 500 | } |
| 501 | if m.loadedSHA == "" || !geoip.Expired(m.loadedType, m.loadedBuild, m.now()) { |
| 502 | return |
| 503 | } |
| 504 | log.Printf("edge: geoip database %s expired (GeoLite2, 30 days after build) and was removed", short(m.loadedSHA)) |
| 505 | m.skipSHA[m.loadedSHA] = "expired" |
| 506 | m.clearLocked() |
| 507 | } |
| 508 | |
| 509 | func (m *geoMirror) fail(category string, err error) error { |
| 510 | m.genMu.Lock() |
| 511 | defer m.genMu.Unlock() |
| 512 | return m.failLocked(category, err) |
| 513 | } |
| 514 | |
| 515 | // failLocked records the category for the heartbeat and logs at most hourly |
| 516 | // while failing. The error text is never logged: it may carry a key or |
| 517 | // bytes; the category is the message (spec §12). |
| 518 | func (m *geoMirror) failLocked(category string, err error) error { |
| 519 | now := m.now() |
| 520 | if m.lastErr == "" { |
| 521 | m.failingAt = now |
| 522 | } |
| 523 | m.lastErr = category |
| 524 | if now.Sub(m.lastFailLog) >= time.Hour { |
| 525 | m.lastFailLog = now |
| 526 | log.Printf("edge: geoip %s; keeping the loaded database", category) |
| 527 | } |
| 528 | return fmt.Errorf("%s: %w", category, err) |
| 529 | } |
| 530 | |
| 531 | // readFeedStatus refreshes the feed reason's inputs, best effort: a |
| 532 | // missing or unreadable feed.json means no feed reason. |
| 533 | func (m *geoMirror) readFeedStatus(ctx context.Context) { |
| 534 | ctx, cancel := context.WithTimeout(ctx, geoPointerReadTimeout) |
| 535 | defer cancel() |
| 536 | raw, err := readCapped(ctx, m.store, geoip.FeedKey, geoip.MaxPointerBytes) |
| 537 | if errors.Is(err, os.ErrNotExist) { |
| 538 | m.genMu.Lock() |
| 539 | m.feedFailing, m.feedBox, m.feedKnown = false, "", true // no feed: confirmed |
| 540 | m.genMu.Unlock() |
| 541 | return |
| 542 | } |
| 543 | if err != nil { |
| 544 | return // keep the last known state: a blip must not clear a firing alert (code review R2-3) |
| 545 | } |
| 546 | st, err := geoip.ParseFeedStatus(raw) |
| 547 | if err != nil { |
| 548 | return |
| 549 | } |
| 550 | m.genMu.Lock() |
| 551 | m.feedFailing, m.feedBox, m.feedKnown = st.Failing(), st.Box, true |
| 552 | m.genMu.Unlock() |
| 553 | } |
| 554 | |
| 555 | // Alert reason codes (geoip spec §10.4), the geoip rule's reading. |
| 556 | const ( |
| 557 | GeoAlertNone = 0 |
| 558 | GeoAlertStale = 1 // the loaded database is over 45 days old |
| 559 | GeoAlertExpiring = 2 // a GeoLite2 database within 9 days of D1 |
| 560 | GeoAlertExpired = 3 // the pointer is expired, marked or by the clock |
| 561 | GeoAlertNotLoaded = 4 // a live pointer not loaded here for over an hour |
| 562 | GeoAlertFeed = 5 // the feed has failed 7 times in a row (the console's box only) |
| 563 | ) |
| 564 | |
| 565 | // AlertCode is the geoip rule's reading for this box: the most severe |
| 566 | // reason that holds (3, 4, 2, 1, then 5), or 0. known=false until both the |
| 567 | // pointer and the feed status have been read (or confirmed absent) once. |
| 568 | func (m *geoMirror) AlertCode(now time.Time, box string) (code float64, known bool) { |
| 569 | m.genMu.Lock() |
| 570 | defer m.genMu.Unlock() |
| 571 | // A reason established from what IS known is reported even when the |
| 572 | // other input is not (code review R5-1): an unreadable feed.json must |
| 573 | // not hide a confirmed expiry. Only "healthy" needs everything known. |
| 574 | if c := m.alertCodeLocked(now, box); c != GeoAlertNone { |
| 575 | return c, true |
| 576 | } |
| 577 | if !m.pointerKnown || !m.feedKnown { |
| 578 | return GeoAlertNone, false |
| 579 | } |
| 580 | return GeoAlertNone, true |
| 581 | } |
| 582 | |
| 583 | func (m *geoMirror) alertCodeLocked(now time.Time, box string) float64 { |
| 584 | // pointerPresent is only ever true after a successful read, and |
| 585 | // feedFailing only after a parsed feed.json, so each reason below rests |
| 586 | // on state that was actually read. |
| 587 | expired := m.pointerPresent && (m.pointerMarked || geoip.Expired(m.pointerType, m.pointerBuild, now)) |
| 588 | switch { |
| 589 | case expired: |
| 590 | return GeoAlertExpired |
| 591 | case m.pointerPresent && !m.wantSince.IsZero() && now.Sub(m.wantSince) > time.Hour: |
| 592 | return GeoAlertNotLoaded |
| 593 | case m.loadedSHA != "" && strings.HasPrefix(m.loadedType, "GeoLite2-") && now.Sub(m.loadedBuild) >= geoip.GeoLiteWarn: |
| 594 | return GeoAlertExpiring |
| 595 | case m.loadedSHA != "" && now.Sub(m.loadedBuild) > geoip.StaleAfter: |
| 596 | return GeoAlertStale |
| 597 | case m.feedFailing && box != "" && m.feedBox == box: |
| 598 | return GeoAlertFeed |
| 599 | } |
| 600 | return GeoAlertNone |
| 601 | } |
| 602 | |
| 603 | // readPointer is one bounded pointer read. |
| 604 | func (m *geoMirror) readPointer(ctx context.Context) ([]byte, error) { |
| 605 | ctx, cancel := context.WithTimeout(ctx, geoPointerReadTimeout) |
| 606 | defer cancel() |
| 607 | return readCapped(ctx, m.store, geoip.PointerKey, geoip.MaxPointerBytes) |
| 608 | } |
| 609 | |
| 610 | // readCapped reads key through OpenObject, refusing more than max bytes. |
| 611 | func readCapped(ctx context.Context, s release.Store, key string, max int) ([]byte, error) { |
| 612 | rc, _, err := release.OpenObject(ctx, s, key) |
| 613 | if err != nil { |
| 614 | return nil, err |
| 615 | } |
| 616 | defer rc.Close() |
| 617 | b, err := io.ReadAll(io.LimitReader(rc, int64(max)+1)) |
| 618 | if err != nil { |
| 619 | return nil, err |
| 620 | } |
| 621 | if len(b) > max { |
| 622 | return nil, fmt.Errorf("%s larger than %d bytes", key, max) |
| 623 | } |
| 624 | return b, nil |
| 625 | } |
| 626 | |
| 627 | // run is the process-lifetime loop: a poll every interval+jitter, each |
| 628 | // bounded by geoMirrorDeadline, and an independent expiry ticker that never |
| 629 | // touches the network. |
| 630 | func (m *geoMirror) run(stop <-chan struct{}) { |
| 631 | go func() { |
| 632 | t := time.NewTicker(geoExpiryInterval) |
| 633 | defer t.Stop() |
| 634 | for { |
| 635 | select { |
| 636 | case <-stop: |
| 637 | return |
| 638 | case <-t.C: |
| 639 | m.ExpireTick() |
| 640 | } |
| 641 | } |
| 642 | }() |
| 643 | for { |
| 644 | // The next pass is due interval+jitter after this one STARTED, not |
| 645 | // after it finished: a pass is bounded by geoMirrorDeadline (10 min), |
| 646 | // so a change to the pointer is seen within interval+jitter (11 min) |
| 647 | // even when a long download was in flight (codex R8-2). |
| 648 | next := time.Now().Add(geoMirrorInterval + rand.N(geoMirrorJitter)) |
| 649 | ctx, cancel := context.WithTimeout(context.Background(), geoMirrorDeadline) |
| 650 | m.Poll(ctx) |
| 651 | cancel() |
| 652 | select { |
| 653 | case <-stop: |
| 654 | return |
| 655 | case <-time.After(time.Until(next)): |
| 656 | } |
| 657 | } |
| 658 | } |
| 659 | |
| 660 | // WithGeoTunnelClient marks this edge as a tunnel client's: it never mirrors |
| 661 | // the GeoIP database and takes the hub's answer instead (spec §5.1). |
| 662 | func WithGeoTunnelClient() RunOption { return func(e *Edge) { e.geoTunnelClient = true } } |
| 663 | |
| 664 | // GeoIPState is the heartbeat block (spec §5.5). |
| 665 | func (e *Edge) GeoIPState() GeoIPState { |
| 666 | if e.geoMirror != nil { |
| 667 | return e.geoMirror.State() |
| 668 | } |
| 669 | if e.geoMode == "" { |
| 670 | return GeoIPState{Mode: "none"} |
| 671 | } |
| 672 | return GeoIPState{Mode: e.geoMode} |
| 673 | } |
| 674 | |
| 675 | // GeoIPAlertCode is the geoip rule's reading for this box (spec §10.4); |
| 676 | // 0 on an edge with no mirror. known=false means "no reading yet". |
| 677 | func (e *Edge) GeoIPAlertCode(now time.Time) (float64, bool) { |
| 678 | if e.geoMirror == nil { |
| 679 | return GeoAlertNone, true |
| 680 | } |
| 681 | return e.geoMirror.AlertCode(now, e.box) |
| 682 | } |
| 683 | |
amadan