Do not raise agent-can-become-root while the first setuid search is within its bound (hq ADR 0266, note E) #175

Merged
mesh-admin merged 2 commits from fix/a-search-not-finished-after-a-restart-is-not-urgent into main 2026-10-09 10:56:15 +00:00
7 changed files with 143 additions and 38 deletions
Showing only changes of commit 2e1a9abbf7 - Show all commits
+53 -17
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@@ -117,35 +117,67 @@ func judgedConfined(agent string, h inventory.NodeHealth, had bool, now time.Tim
h.SaidAt.Local().Format("2006-01-02 15:04"))
}
// searchQuietFor is how long a verdict may say its setuid search is still running before that is itself the
// urgent condition: the node-engine's bound on one search, and one statement more (a node-engine states its
// health at least every five minutes) for the verdict that follows it to be heard.
const searchQuietFor = link.RootSearchBound + 5*time.Minute
// searchQuietFor is how long the controller lets an agent account's verdict wait for the node-engine's setuid
// search before that is itself the urgent condition: the engine's bound on one search (link.RootSearchBound, the
// engine's own value), counted from when this controller first saw it waiting, never from the engine's start.
const searchQuietFor = link.RootSearchBound
// searchStillRunning says the one thing keeping an agent account from being judged is the node-engine's first
// search for setuid programs, still within its bound (novox/hq ADR 0266): a fresh statement from an engine that
// judges root, holding a verdict on the account, every verdict on it healthy or not judged yet because that
// search runs — and none of those for longer than searchQuietFor. A way to root found, a search that failed or
// did not finish, any other unknown, a stale statement: false, and DA raises it.
func searchStillRunning(agent string, h inventory.NodeHealth, had bool, now time.Time) bool {
// The kinds of an agent account's verdict, for the quiet a search earns.
const (
verdictOther = iota // anything else: a stale statement, an older engine, no verdict, another unknown
verdictPending // waiting for the search, and otherwise healthy
verdictComplete // judged: healthy, or a way to root found
)
// rootVerdictKind reads a statement for the agent account (novox/hq ADR 0266): pending when every verdict on it
// is healthy or not judged yet because the engine's setuid search runs, at least one of them that; complete when
// every verdict is healthy or one found a way to root. The engine's own "since" is not read: it starts again at
// every restart of the engine.
func rootVerdictKind(agent string, h inventory.NodeHealth, had bool, now time.Time) int {
if !had || now.Sub(h.HeardAt) > verdictFreshFor || h.Contract < link.RootContract {
return false
return verdictOther
}
pending := false
pending, any := false, false
for _, r := range h.Resources {
if r.Kind != link.KindAccount || r.Target != agent || r.Root != link.RootNever {
continue
}
any = true
switch {
case r.State == link.StateHealthy:
case r.State == link.StateUnknown && strings.HasPrefix(r.Reason, link.ReasonRootPending) &&
!r.Since.IsZero() && now.Sub(r.Since) <= searchQuietFor:
case r.State == link.StateUnhealthy:
return verdictComplete
case r.State == link.StateUnknown && strings.HasPrefix(r.Reason, link.ReasonRootPending):
pending = true
default:
return false
return verdictOther
}
}
return pending
switch {
case !any:
return verdictOther
case pending:
return verdictPending
}
return verdictComplete
}
// searchStillRunning says the one thing keeping an agent account from being judged is the node-engine's setuid
// search, and that this controller first saw it waiting less than searchQuietFor ago — kept in the store, so a
// node-engine restarted in a loop does not keep it quiet. A complete verdict forgets when it began.
func searchStillRunning(ctx context.Context, inv *inventory.Inventory, node, agent string, h inventory.NodeHealth,
had bool, now time.Time) (bool, error) {
switch rootVerdictKind(agent, h, had, now) {
case verdictComplete:
return false, inv.RootSearchJudged(ctx, node)
case verdictPending:
since, err := inv.RootSearchPending(ctx, node, now)
if err != nil {
return false, err
}
return now.Sub(since) <= searchQuietFor, nil
}
return false, nil
}
// probeAgentAccounts is DA: every machine that names an agent account has it judged, on its node-engine's
@@ -166,6 +198,10 @@ func probeAgentAccounts(ctx context.Context, d *doctor) ([]conditions.Observatio
return nil, err
}
now := time.Now()
quiet, err := searchStillRunning(ctx, inv, n.Name, n.AgentAccount, h, had, now)
if err != nil {
return nil, err
}
confined, why := judgedConfined(n.AgentAccount, h, had, now)
if confined {
continue
@@ -174,7 +210,7 @@ func probeAgentAccounts(ctx context.Context, d *doctor) ([]conditions.Observatio
// urgent condition after every restart. The agent is still not confined — ADR 0259's router reads
// agentConfined, not this — and `node show` still says not judged. Loud again once the search fails,
// runs out its bound, or the statement goes stale.
if searchStillRunning(n.AgentAccount, h, had, now) {
if quiet {
continue
}
out = append(out, conditions.Observation{Scope: conditions.ScopeMachine, ID: n.Name, Token: "agent-root",
+34 -15
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@@ -1,6 +1,7 @@
package main
import (
"github.com/novox/mesh-host/rootsearch"
"strings"
"testing"
"time"
@@ -199,10 +200,14 @@ func TestTheNodeVerbOnlyShows(t *testing.T) {
}
// After every node-engine restart its search for setuid programs runs for up to its bound, and the agent account
// is not judged until it ends. DA does not raise that as urgent while the search is within its bound — the
// account is still not confined, and `node show` still says not judged — and raises it once the search failed,
// ran out its bound, or found a way to root.
// is not judged until it ends. DA does not raise that as urgent while the search is within its bound, counted from
// when this controller first saw it waiting — never from the engine's own "since", which a restart resets, so an
// engine restarted in a loop does not keep it quiet. The account is still not confined, and `node show` still
// says not judged; a search that failed, or a way to root found, is urgent at once.
func TestASearchStillRunningAfterARestartIsNotUrgent(t *testing.T) {
if searchQuietFor != rootsearch.Bound {
t.Fatalf("the quiet is %s and the node-engine's bound %s: they are one value", searchQuietFor, rootsearch.Bound)
}
open := aMesh(t)
ctx := t.Context()
inv := open.inventory
@@ -215,11 +220,12 @@ func TestASearchStillRunningAfterARestartIsNotUrgent(t *testing.T) {
t.Fatal(err)
}
d := &doctor{open: open}
say := func(state, reason string, since time.Time) []conditions.Observation {
say := func(state, reason string) []conditions.Observation {
t.Helper()
// The engine's since is always now: it was just restarted.
v := inventory.ResourceHealth{Module: "claude-code", Resource: "claude-code.agent-account",
Kind: link.KindAccount, Target: "agent", State: state, Reason: reason, Root: link.RootNever,
Account: "agent", Since: since}
Account: "agent", Since: time.Now()}
if _, err := inv.RecordHealth(ctx, inventory.NodeHealth{Node: "anchor", Contract: link.RootContract,
SaidAt: time.Now(), HeardAt: time.Now(), Resources: []inventory.ResourceHealth{v}}); err != nil {
t.Fatal(err)
@@ -231,23 +237,36 @@ func TestASearchStillRunningAfterARestartIsNotUrgent(t *testing.T) {
return onlyMachine(found, "anchor")
}
running := link.ReasonRootPending + ": the search for setuid programs, started at 19:21, has not finished yet"
if found := say(link.StateUnknown, running, time.Now().Add(-2*time.Minute)); len(found) != 0 {
t.Fatalf("a search two minutes into its bound was raised: %+v", found)
healthy := func() {
t.Helper()
if found := say(link.StateHealthy, ""); len(found) != 0 {
t.Fatalf("a healthy verdict raised: %+v", found)
}
}
if found := say(link.StateUnknown, running); len(found) != 0 {
t.Fatalf("a search first seen now was raised: %+v", found)
}
if _, confined, why, _ := agentConfined(ctx, inv, "anchor"); confined || !strings.Contains(why, "not judged") {
t.Fatalf("an account whose search runs was read as confined: %q", why)
}
if found := say(link.StateUnknown, running, time.Now().Add(-searchQuietFor-time.Minute)); len(found) != 1 ||
found[0].Severity != conditions.Urgent {
t.Fatalf("a search past its bound was not urgent: %+v", found)
// The engine restarted again and again, each statement's own since fresh: the controller's clock runs on.
if _, err := inv.RootSearchPending(ctx, "anchor", time.Now().Add(-searchQuietFor-time.Minute)); err != nil {
t.Fatal(err)
}
incomplete := "not judged (search incomplete): the search for setuid programs did not finish (last tried at 19:23: " +
"timeout); it is tried again later"
if found := say(link.StateUnknown, incomplete, time.Now().Add(-time.Minute)); len(found) != 1 ||
found[0].Severity != conditions.Urgent {
healthy() // a complete verdict forgets when the waiting began …
if _, err := inv.RootSearchPending(ctx, "anchor", time.Now().Add(-searchQuietFor-time.Minute)); err != nil {
t.Fatal(err) // … and this restart loop began past the bound
}
if found := say(link.StateUnknown, running); len(found) != 1 || found[0].Severity != conditions.Urgent {
t.Fatalf("a search pending past the bound, by the controller's clock, was not urgent: %+v", found)
}
healthy()
incomplete := rootsearch.ReasonIncomplete + ": the search for setuid programs did not finish (last tried at " +
"19:23: timeout); it is tried again later"
if found := say(link.StateUnknown, incomplete); len(found) != 1 || found[0].Severity != conditions.Urgent {
t.Fatalf("a search that did not finish was not urgent: %+v", found)
}
if found := say(link.StateUnhealthy, link.ReasonRoot+": in the group docker; "+running, time.Now()); len(found) != 1 ||
if found := say(link.StateUnhealthy, link.ReasonRoot+": in the group docker; "+running); len(found) != 1 ||
found[0].Severity != conditions.Urgent {
t.Fatalf("a way to root found while the search runs was not urgent: %+v", found)
}
@@ -0,0 +1,9 @@
-- The controller keeps when it first saw an agent account's root verdict waiting for the node-engine's search
-- for setuid programs (novox/hq ADR 0266), cleared by the next complete verdict.
--
-- The self-check does not raise `agent-can-become-root` while that search is within its bound, so a restart is
-- not an urgent condition each time. The node-engine's own "since" starts again at every restart: an agent
-- that restarted the engine in a loop kept the condition quiet for ever. This time is the controller's, kept
-- across the engine's restarts and its own, so the quiet ends once the bound has passed since the search first
-- read as pending, however often the engine started again.
alter table node add column agent_root_pending_since timestamptz;
+21
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@@ -1292,3 +1292,24 @@ func (i *Inventory) Sequence(ctx context.Context, id string) (int64, error) {
}
return *n, nil
}
// RootSearchPending keeps when the controller first saw this node's agent account waiting for the node-engine's
// setuid search (novox/hq ADR 0266) and answers it: the first time it is seen since the last complete verdict,
// at, kept; seen again, what was kept. Kept across the engine's restarts and the controller's own.
func (i *Inventory) RootSearchPending(ctx context.Context, node string, at time.Time) (time.Time, error) {
var since time.Time
err := i.store.Pool().QueryRow(ctx,
`update node set agent_root_pending_since = coalesce(agent_root_pending_since, $2)
where name = $1 returning agent_root_pending_since`, node, at).Scan(&since)
if errors.Is(err, pgx.ErrNoRows) {
return time.Time{}, fmt.Errorf("%w: %s", ErrNoSuchNode, node)
}
return since, err
}
// RootSearchJudged forgets when a search began pending: a complete verdict came.
func (i *Inventory) RootSearchJudged(ctx context.Context, node string) error {
_, err := i.store.Pool().Exec(ctx,
`update node set agent_root_pending_since = null where name = $1 and agent_root_pending_since is not null`, node)
return err
}
+6 -6
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@@ -8,6 +8,7 @@ package link
import (
"encoding/base64"
"github.com/novox/mesh-host/rootsearch"
"strconv"
"strings"
"time"
@@ -431,14 +432,13 @@ const RootContract = 3
const ReasonRoot = "can become root without a person"
// ReasonRootPending starts the reason of an account verdict the node-engine cannot give yet because its search
// for setuid programs, started when the engine started, has not finished (mesh-host internal/accounts
// ReasonPending): not judged yet, said as such, never a pass. The search is bounded (RootSearchBound); one that
// fails or runs out its bound is said in other words, as not judged (search incomplete).
const ReasonRootPending = "not judged yet (search running)"
// for setuid programs, started when the engine started, has not finished: not judged yet, said as such, never a
// pass. The node-engine's own words (mesh-host rootsearch.ReasonPending), read from it rather than copied.
const ReasonRootPending = rootsearch.ReasonPending
// RootSearchBound is the longest the node-engine lets one search for setuid programs run (mesh-host
// internal/accounts SearchBound).
const RootSearchBound = 15 * time.Minute
// rootsearch.Bound): the one value both read.
const RootSearchBound = rootsearch.Bound
// RootNever is the value of a user's `root`, and of a verdict's Root, that the account must never become
// root without a person (ADR 0266).
+19
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@@ -0,0 +1,19 @@
// Package rootsearch holds what the node-engine's search for setuid programs and the controller that reads its
// verdicts must agree on (novox/hq ADR 0266): how long one search may run, and the words a verdict starts with
// while it has no answer. Public, so the controller imports these rather than keeps copies that could drift.
package rootsearch
import "time"
// Bound is how long one search for setuid programs may run. It governs the whole search, the walk and the
// package manager's answers together; the controller does not raise an agent account as not judged while the
// first search after a start is within it.
const Bound = 15 * time.Minute
// The reasons of a root verdict the search could not answer yet.
const (
// ReasonPending starts the reason while the first search since the engine started runs.
ReasonPending = "not judged yet (search running)"
// ReasonIncomplete starts the reason when no search has finished: one failed or ran out its bound.
ReasonIncomplete = "not judged (search incomplete)"
)
+1
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@@ -78,6 +78,7 @@ github.com/nats-io/nuid
# github.com/novox/mesh-host v0.0.0 => git.novox.be/novox/mesh-host v0.0.0-20261009103656-1c61b72f354d
## explicit; go 1.26.0
github.com/novox/mesh-host/internal/declaration
github.com/novox/mesh-host/rootsearch
github.com/novox/mesh-host/validate
# go.uber.org/automaxprocs v1.6.0
## explicit; go 1.20