Revert L3 (mesh-host, merge 0a4c35f): its node-engine removed every held module on novox, the bus server among them, at 08:54 CET on 2026-10-29 (issue 774)

L3 lands again with two fixes: a held module is never removed, and the grants cover L3's new subjects.

internal/selfcompose/selfcompose.go

@@ -12,9 +12,7 @@ package selfcompose
 
 import (
 	"context"
-	"crypto/ed25519"
 	"crypto/sha256"
-	"encoding/base64"
 	"encoding/hex"
 	"encoding/json"
 	"errors"
@@ -30,7 +28,6 @@ import (
 	"git.novox.be/novox/mesh-sdk/go/compose"
 	"git.novox.be/novox/mesh-sdk/go/compose/frombus"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
-	"git.novox.be/novox/mesh-sdk/go/overlay"
 
 	"github.com/nats-io/nats.go"
 
@@ -78,13 +75,6 @@ type Env struct {
 	// Fetch reads an archive at a URL in the artifact store: a moved module's templates archive, whose texts its built
 	// manifest carries (issue 1126). Read once per digest. Nil reads none, and a moved module does not compose.
 	Fetch func(ctx context.Context, url string) ([]byte, error)
-	// VaultAuthority is the vault's authority as this node read it from the vault's `signers` (ADR 0550 §2), composed
-	// beside the controller's as the mesh's authority (frombus.SignersReader); "" or nil composes the controller's alone.
-	VaultAuthority func() string
-	// Certify asks the vault's `sign` for this node's own certificate, keeps it and writes the node's record again (ADR
-	// 0550 §2): asked only when a module placed here asks for a certificate and the record holds none from an authority
-	// the node trusts. Nil asks nothing, and such a module stands in, as before.
-	Certify func(ctx context.Context) error
 }
 
 // VaultSecretChanged is the vault's event that a secret changed: a name and its generation, never a value.
@@ -109,8 +99,6 @@ type Composer struct {
 	// sealedOwn is each own secret's sealed value as first handed, by module/name and generation: a value sealed again
 	// is other bytes, so the one first had is kept while the generation stands, and the composition stays the same.
 	sealedOwn map[string]ownSealed
-	// certified is the serving key a certificate was last asked for successfully, so it is asked once per key.
-	certified string
 	said      string
 	refusal   string
 	// held is what the composer's last pass held: each module refused alone, and the node's own ("node") when it could
@@ -513,8 +501,6 @@ func (c *Composer) compose(ctx context.Context) []agent.Update {
 	if c.env.Running != nil {
 		running = c.env.Running()
 	}
-	// Its own certificate, asked of the vault when a module here asks for one and the record holds none it trusts.
-	c.certifyIfWanted(ctx, r, own)
 	scope := frombus.Scope{Node: c.env.Node, KeptAt: kept, InOwn: inOwn, Running: running}
 	missed := c.missed.Load()
 	compositions, _, held, err := frombus.Compose(ctx, r, c.env.Mesh, scope, fps)
@@ -760,69 +746,6 @@ func (c *Composer) Policy(ctx context.Context, module string) string {
 // reader is the composer's view of the bus as frombus reads it.
 type reader struct{ c *Composer }
 
-// VaultAuthority is the vault's authority the node follows (frombus.SignersReader).
-func (r reader) VaultAuthority(context.Context) string {
-	if r.c.env.VaultAuthority == nil {
-		return ""
-	}
-	return r.c.env.VaultAuthority()
-}
-
-var _ frombus.SignersReader = reader{}
-
-// certificateWanted says whether a module the placement p puts on this node asks for a certificate for the machine's
-// internal name (its manifest's `certificate`), read from the indexer's manifests; a manifest that cannot be read is
-// taken as asking none, and the composition says what it misses.
-func (c *Composer) certificateWanted(ctx context.Context, r reader, p delivery.Placement) bool {
-	for _, m := range p.Modules {
-		c.mu.Lock()
-		digest := c.modules[m.Module].Manifest
-		c.mu.Unlock()
-		if digest == "" {
-			continue
-		}
-		raw, err := r.Manifest(ctx, digest)
-		if err != nil {
-			continue
-		}
-		if parsed, err := catalogue.ParseManifestForInputs(raw); err == nil && parsed.Certificate != nil {
-			return true
-		}
-	}
-	return false
-}
-
-// certifyIfWanted asks Certify once per serving key when a module placed here asks for a certificate and this node's
-// record holds none for its internal name and serving key from an authority it trusts (the one it holds, or the vault's).
-func (c *Composer) certifyIfWanted(ctx context.Context, r reader, p delivery.Placement) {
-	if c.env.Certify == nil || !c.certificateWanted(ctx, r, p) {
-		return
-	}
-	c.mu.Lock()
-	rec, ok := c.records[c.env.Node]
-	asked := c.certified
-	c.mu.Unlock()
-	if !ok || rec.ServingKey == "" || asked == rec.ServingKey {
-		return
-	}
-	key, err := base64.StdEncoding.DecodeString(rec.ServingKey)
-	if err != nil || len(key) != ed25519.PublicKeySize {
-		return
-	}
-	trusted := []string{rec.Authority, r.VaultAuthority(ctx)}
-	if rec.Certificate != "" && delivery.CheckNodeCertificate(rec.Certificate, trusted, overlay.InternalName(c.env.Node),
-		ed25519.PublicKey(key), time.Now()) == nil {
-		return
-	}
-	if err := c.env.Certify(ctx); err != nil {
-		c.sayOnce(fmt.Sprintf("a module here asks for a certificate, and the vault's sign gave none: %v", err))
-		return
-	}
-	c.mu.Lock()
-	c.certified = rec.ServingKey
-	c.mu.Unlock()
-}
-
 func (r reader) Placements(context.Context) (map[string]delivery.Placement, error) {
 	r.c.mu.Lock()
 	defer r.c.mu.Unlock()

internal/selfcompose/selfcompose_test.go

@@ -3,7 +3,6 @@ package selfcompose
 import (
 	"context"
 	"crypto/sha256"
-	"encoding/base64"
 	"encoding/hex"
 	"encoding/json"
 	"fmt"
@@ -1220,32 +1219,6 @@ func TestTheNodeComposesItsWantsFromTheBus(t *testing.T) {
 		}
 	}
 	b.mu.Unlock()
-
-	// L3 s7 (ADR 0550 §2): the node asks the vault for its own certificate only when a module placed here asks for one
-	// and its record holds none from an authority it trusts; once per serving key.
-	certBus := newFakeBus()
-	certAsks := 0
-	certEnv := certBus.env()
-	certEnv.Certify = func(context.Context) error { certAsks++; return nil }
-	certEnv.VaultAuthority = func() string { return "" }
-	cc := New(certEnv)
-	withCert := `{"module":"web","version":"1","certificate":{"into":"/etc/web/tls.crt"}}`
-	cdigest := delivery.ManifestDigest([]byte(withCert))
-	cc.manifests[digest] = []byte(lemurs)
-	cc.manifests[cdigest] = []byte(withCert)
-	cc.modules = map[string]delivery.Module{"lemurs": {Manifest: digest}, "web": {Manifest: cdigest}}
-	cc.records["n1"] = delivery.NodeRecord{Node: "n1", ServingKey: base64.StdEncoding.EncodeToString(make([]byte, 32))}
-	onlyLemurs := delivery.Placement{Node: "n1", Modules: []delivery.PlacedModule{{Module: "lemurs"}}}
-	cc.certifyIfWanted(context.Background(), reader{c: cc}, onlyLemurs)
-	if certAsks != 0 {
-		t.Errorf("no module asks for a certificate, and the vault was asked %d times", certAsks)
-	}
-	withWeb := delivery.Placement{Node: "n1", Modules: []delivery.PlacedModule{{Module: "lemurs"}, {Module: "web"}}}
-	cc.certifyIfWanted(context.Background(), reader{c: cc}, withWeb)
-	cc.certifyIfWanted(context.Background(), reader{c: cc}, withWeb)
-	if certAsks != 1 {
-		t.Errorf("a module asks for a certificate: the vault was asked %d times, want once", certAsks)
-	}
 }
 
 // patternBus is a bus whose every watch gets the updates of its bucket matching its pattern, as the bus's own watches