Files
felhom-controller/controller/internal/report/escrow_confirm.go
T

162 lines
7.4 KiB
Go

package report
import (
"context"
"log"
"sync"
"time"
)
// SLICE 3 — hub-verified escrow auto-confirm. Replaces operator trust ("I ran the ceremony, click
// confirm") with a verified fact: the hub's report ACK carries the sha256 of the repo password the
// stored escrow blob COVERS (recorded at ceremony time); the controller flips pending→escrowed ONLY
// when that hash matches sha256 of its CURRENT local repo password. Blob-presence alone must never
// confirm — a blob can predate the current password (re-provision, inject, drive history) and a
// truthful-looking claim on a stale blob would re-open the exact un-recoverable-ciphertext gap fork-4
// closed. Hashes are non-reversible (256-bit random secrets) and safe to log; passwords never are.
// EscrowStatus mirrors the hub ACK's `escrow` object (nil when the hub has no escrow row).
type EscrowStatus struct {
IdentityBlobPresent bool `json:"identity_blob_present"`
ResticPwSHA256 string `json:"restic_pw_sha256"`
CreatedAt string `json:"created_at"`
}
// EscrowAutoConfirmer runs the auto-confirm check on each report ACK. Long-lived (one per process) so
// the mismatch warning dedupes per distinct hash instead of firing every 15-minute cycle.
type EscrowAutoConfirmer struct {
// Pending reports whether the offbox target is configured AND EscrowState=="pending" — the
// confirm-flip state. "escrowed" is never flipped back (auto-UN-confirm does not exist), but
// since v0.127.0 it IS re-checked: see Escrowed + the stale-blob branch (Scenario F).
Pending func() bool
// Escrowed reports whether the offbox target is configured AND EscrowState=="escrowed" — the
// v0.127.0 stale-blob re-check state (Scenario F: a superseding ceremony that did NOT cover
// the current password — e.g. a CLI run without the staged secret — must be surfaced, not
// silently ignored; the spike left the drill box in exactly that state). nil → no re-check.
Escrowed func() bool
// LocalHash returns the canonical hash of the local repo password (ok=false → no password file).
LocalHash func() (hash string, ok bool)
// Flip transitions EscrowState pending→escrowed (settings.UpdateOffboxStatus).
Flip func() error
// Wipe removes the agent-staged secret (best-effort — the flip is the primary effect).
Wipe func(ctx context.Context) error
Logger *log.Logger
mu sync.Mutex
warnedHash string // last mismatched hub hash we warned about (dedupe; shared by both branches)
stale bool // Scenario F: the hub blob does not cover the CURRENT password (display-only)
}
// staleHashlessMarker is the warnedHash dedupe sentinel for the hash-less supersession case
// (the hub hash is EMPTY there, which must still warn exactly once, and must not collide with
// the zero value of warnedHash).
const staleHashlessMarker = "(hashless)"
// StaleBlob reports the Scenario-F display flag: EscrowState is escrowed but the hub's CURRENT
// blob does not cover the current repo password. In-memory only (recomputed from ACKs after a
// restart); NEVER blocks runs and NEVER flips state — the web card renders the warning + the
// re-ceremony CTA from it.
func (c *EscrowAutoConfirmer) StaleBlob() bool {
c.mu.Lock()
defer c.mu.Unlock()
return c.stale
}
func (c *EscrowAutoConfirmer) logf(f string, a ...any) {
if c.Logger != nil {
c.Logger.Printf(f, a...)
}
}
// Reconcile applies one ACK's escrow status. Scenarios: match → flip+wipe (A); mismatch → stay pending
// + warn once per hash (B); no status / no hash / no local file → stay pending silently (C, normal
// onboarding); escrowed → the v0.127.0 stale-blob re-check (F — warn-only, never a state change);
// otherwise → no-op (E — offbox not configured).
func (c *EscrowAutoConfirmer) Reconcile(es *EscrowStatus) {
if es == nil {
return
}
if !c.Pending() {
// Scenario F (v0.127.0): an ESCROWED box re-checks the hash on every ACK — a superseding
// blob that does not cover the current password must be surfaced (warn + card flag), while
// runs continue and the state stays escrowed (no auto-UN-confirm, ever).
if c.Escrowed != nil && c.Escrowed() {
c.reconcileEscrowed(es)
}
return
}
// Fail-closed: the hash must exist AND ride a present identity blob (the hash-bearing container).
// A hash-less blob is a legacy/password-less escrow — the deprecated manual confirm covers those.
if es.ResticPwSHA256 == "" || !es.IdentityBlobPresent {
return
}
localHash, ok := c.LocalHash()
if !ok {
return // no local repo password file — nothing to verify against
}
if localHash != es.ResticPwSHA256 {
// The stored escrow does NOT cover the current key — flipping would be a false custody claim.
c.mu.Lock()
warned := c.warnedHash == es.ResticPwSHA256
c.warnedHash = es.ResticPwSHA256
c.mu.Unlock()
if !warned {
c.logf("[WARN] [escrow-confirm] the hub's escrow blob does not cover the CURRENT repo password (hub hash %.12s… != local %.12s…) — run the escrow ceremony (wizard /backup/escrow, or felhom-agent --selftest=escrow-create --upload); staying pending", es.ResticPwSHA256, localHash)
}
return
}
if err := c.Flip(); err != nil {
c.logf("[ERROR] [escrow-confirm] hash matched but the escrowed flip failed (retries next cycle): %v", err)
return
}
c.logf("[INFO] [escrow-confirm] hub-verified: the escrow covers the current repo password (hash %.12s…) — EscrowState auto-confirmed escrowed; offsite runs enabled", es.ResticPwSHA256)
if c.Wipe != nil {
wctx, cancel := context.WithTimeout(context.Background(), 15*time.Second)
defer cancel()
if err := c.Wipe(wctx); err != nil {
c.logf("[ERROR] [escrow-confirm] escrowed but the agent-staged secret was NOT wiped: %v", err)
}
}
c.mu.Lock()
c.stale = false // a fresh hub-verified confirm clears any earlier stale flag
c.mu.Unlock()
}
// reconcileEscrowed is the Scenario-F branch (§8 truth table, escrowed rows): compare the ACK's
// hash exactly as the pending branch does; a mismatch OR a present blob with an EMPTY hash (the
// hash-less supersession — the spike's exact case) raises the stale flag + ONE warn per distinct
// hub hash (warnedHash reuse); a match clears the flag. State is never flipped; runs never block
// (offsite backups still protect against non-total loss).
func (c *EscrowAutoConfirmer) reconcileEscrowed(es *EscrowStatus) {
localHash, ok := c.LocalHash()
if !ok {
return // no local repo password file — nothing to compare against
}
hubHash := es.ResticPwSHA256
if hubHash != "" && hubHash == localHash {
c.mu.Lock()
c.stale = false
c.mu.Unlock()
return
}
// Stale: hash mismatch, or a blob whose hash is empty (hash-less supersession). Dedupe the
// warn per distinct hub hash; the empty hash dedupes under a sentinel so it still fires once.
dedupeKey := hubHash
if dedupeKey == "" {
dedupeKey = staleHashlessMarker
}
c.mu.Lock()
warned := c.warnedHash == dedupeKey
c.warnedHash = dedupeKey
c.stale = true
c.mu.Unlock()
if warned {
return
}
if hubHash == "" {
c.logf("[WARN] [escrow-confirm] STALE escrow: the hub's current blob carries NO password hash (hash-less supersession) — the stored recovery bundle does not cover the offsite password; create a new recovery code (wizard /backup/escrow). State stays escrowed; runs continue")
return
}
c.logf("[WARN] [escrow-confirm] STALE escrow: the hub's current blob does not cover the CURRENT repo password (hub hash %.12s… != local %.12s…) — create a new recovery code (wizard /backup/escrow). State stays escrowed; runs continue", hubHash, localHash)
}