Judge the installer's user list against mesh-host with the groups grant (hq issue 525)

The controller now asks mesh-delivery.groups, and mesh-host a76baa4b carries
that grant in the installer's first user list (mesh-host #85). The captured
copy is moved to that commit so the genesis test judges the list that ships.

testdata/beside/CAPTURED

@@ -8,7 +8,7 @@ private addresses. That is acceptable while mesh-controller is private; if it ev
 a second place to clean besides the catalogue itself.
 
 mesh-catalog  b9de001833b1b61b297182b8e3bcdae1cbdeace9  modules/*/module.json, modules/nats/Dockerfile
-mesh-host     bd5cc6980419c1bd4824be6d58dfebd2381a9de3  examples/foundation-first-node-nats.lock
+mesh-host     a76baa4b47f07a8b2bab065603414530bd02b53a  examples/foundation-first-node-nats.lock
 mesh-sdk      33917f91ac3cc213b879b32f3c70e2aa70395f98  conformance/events/module-event.json
 
 To move them, from this repository's root, with the two repositories checked out beside it:

testdata/beside/mesh-host/examples/foundation-first-node-nats.lock

@@ -161,7 +161,7 @@
       "type": "file",
       "path": "/var/lib/mesh-bus-conf/accounts.conf",
       "mode": "0600",
-      "content": "// The first user list, carried by the installer because at genesis there is no mesh to\n// compose one. A bootstrap credential, rotated with the store's and replaced by the\n// controller's own composition from its first start onward.\naccounts {\n  MESH {\n    jetstream: enabled\n    users = [\n      { user: \"controller\", password: \"$2a$10$AHqJgOifIVbU41KmATiMhuXFs8xa7Wl2HuN4UVBCXdN2jIQzjqApy\", permissions: {\n        publish: { allow: [\"$JS.ACK.CONTROL.controller.>\", \"$JS.ACK.EVENTS.controller.>\", \"$JS.ACK.DEAD_LETTER_NOTICES.controller.>\", \"$JS.API.>\", \"$KV.mesh-controller_asked.>\", \"$KV.mesh-controller_calls.>\", \"$KV.mesh-controller_hand-acts.>\", \"$KV.mesh-controller_conditions.>\", \"$KV.mesh-controller_condition-history.>\", \"$KV.mesh-controller_lease.>\", \"$KV.SEAT_MESH_BUILD_MACHINE_cancelled.>\", \"$KV.SEAT_NODE_BUILD_AGENT_cancelled.>\", \"_INBOX.enrol.>\", \"mesh.assignment.>\", \"mesh.mod.*.tool.>\", \"mesh.node.>\", \"mesh.seat.mesh-build-machine.accept.>\", \"mesh.seat.node-build-agent.accept.>\", \"mesh.seat.mesh-build-machine.tool.>\", \"mesh.seat.node-build-agent.tool.>\", \"mesh.seat.mesh-controller.event.applied\", \"mesh.seat.mesh-controller.event.built-before\", \"mesh.seat.mesh-controller.event.refused\", \"mesh.seat.mesh-controller.event.rolled-back\", \"mesh.seat.mesh-controller.event.checked\", \"mesh.seat.mesh-controller.event.plan-moved\", \"mesh.seat.mesh-controller.event.condition-raised\", \"mesh.seat.mesh-controller.event.condition-changed\", \"mesh.seat.mesh-controller.event.condition-cleared\", \"mesh.seat.mesh-controller.event.doctor-heartbeat\", \"mesh.seat.mesh-controller.event.secret-replaced\", \"mesh.seat.mesh-controller.event.healer-acted\", \"$SRV.INFO\", \"mesh.seat.node-intrusion-prevention.tool.banned.*\", \"mesh.seat.node-backup.tool.backed-up.*\", \"mesh.seat.node-backup.tool.now.*\", \"mesh.seat.mesh-delivery.tool.stalled\", \"mesh.seat.mesh-delivery.tool.close\", \"mesh.seat.node-launcher.tool.secret.*\", \"mesh.seat.mesh-delivery.tool.release\", \"mesh.seat.mesh-delivery.tool.stop\", \"mesh.seat.mesh-delivery.tool.times\", \"mesh.seat.node-service-manager.tool.restart.*\", \"mesh.seat.mesh-controller.tool.plans\", \"mesh.events.dead.>\", \"mesh.again.>\"] }\n        subscribe: { allow: [\"$JS.API.>\", \"$JS.EVENT.ADVISORY.CONSUMER.MAX_DELIVERIES.>\", \"$JS.EVENT.ADVISORY.CONSUMER.DELETED.>\", \"_DELIVER.controller\", \"_DELIVER.controller.>\", \"_INBOX.controller.>\", \"mesh.control.>\", \"mesh.mod.*.event.provisioner.failing\", \"mesh.mod.*.event.provisioner.recovered\", \"mesh.mod.*.event.provisioner.retirement\", \"mesh.mod.gitea.event.pull.merged\", \"mesh.mod.gitea.event.pull.updated\", \"mesh.mod.mesh-catalog.event.catching-up\", \"mesh.mod.mesh-catalog.event.upgraded\", \"mesh.seat.mesh-build-machine.event.built\", \"mesh.seat.node-build-agent.event.built\", \"mesh.seat.operator-channel.event.decided.mesh-controller\", \"mesh.seat.mesh-controller.tool.>\", \"$SRV.PING\", \"$SRV.INFO\", \"$SRV.PING.mesh-controller\", \"$SRV.PING.mesh-controller.>\", \"$SRV.INFO.mesh-controller\", \"$SRV.INFO.mesh-controller.>\", \"$SRV.STATS\", \"$SRV.STATS.mesh-controller\", \"$SRV.STATS.mesh-controller.>\"] }\n        allow_responses: { max: 1, ttl: \"1m\" }\n      } }\n    ]\n  }\n}\n"
+      "content": "// The first user list, carried by the installer because at genesis there is no mesh to\n// compose one. A bootstrap credential, rotated with the store's and replaced by the\n// controller's own composition from its first start onward.\naccounts {\n  MESH {\n    jetstream: enabled\n    users = [\n      { user: \"controller\", password: \"$2a$10$AHqJgOifIVbU41KmATiMhuXFs8xa7Wl2HuN4UVBCXdN2jIQzjqApy\", permissions: {\n        publish: { allow: [\"$JS.ACK.CONTROL.controller.>\", \"$JS.ACK.EVENTS.controller.>\", \"$JS.ACK.DEAD_LETTER_NOTICES.controller.>\", \"$JS.API.>\", \"$KV.mesh-controller_asked.>\", \"$KV.mesh-controller_calls.>\", \"$KV.mesh-controller_hand-acts.>\", \"$KV.mesh-controller_conditions.>\", \"$KV.mesh-controller_condition-history.>\", \"$KV.mesh-controller_lease.>\", \"$KV.SEAT_MESH_BUILD_MACHINE_cancelled.>\", \"$KV.SEAT_NODE_BUILD_AGENT_cancelled.>\", \"_INBOX.enrol.>\", \"mesh.assignment.>\", \"mesh.mod.*.tool.>\", \"mesh.node.>\", \"mesh.seat.mesh-build-machine.accept.>\", \"mesh.seat.node-build-agent.accept.>\", \"mesh.seat.mesh-build-machine.tool.>\", \"mesh.seat.node-build-agent.tool.>\", \"mesh.seat.mesh-controller.event.applied\", \"mesh.seat.mesh-controller.event.built-before\", \"mesh.seat.mesh-controller.event.refused\", \"mesh.seat.mesh-controller.event.rolled-back\", \"mesh.seat.mesh-controller.event.checked\", \"mesh.seat.mesh-controller.event.plan-moved\", \"mesh.seat.mesh-controller.event.condition-raised\", \"mesh.seat.mesh-controller.event.condition-changed\", \"mesh.seat.mesh-controller.event.condition-cleared\", \"mesh.seat.mesh-controller.event.doctor-heartbeat\", \"mesh.seat.mesh-controller.event.secret-replaced\", \"mesh.seat.mesh-controller.event.healer-acted\", \"$SRV.INFO\", \"mesh.seat.node-intrusion-prevention.tool.banned.*\", \"mesh.seat.node-backup.tool.backed-up.*\", \"mesh.seat.node-backup.tool.now.*\", \"mesh.seat.mesh-delivery.tool.stalled\", \"mesh.seat.mesh-delivery.tool.close\", \"mesh.seat.node-launcher.tool.secret.*\", \"mesh.seat.mesh-delivery.tool.release\", \"mesh.seat.mesh-delivery.tool.stop\", \"mesh.seat.mesh-delivery.tool.times\", \"mesh.seat.mesh-delivery.tool.groups\", \"mesh.seat.node-service-manager.tool.restart.*\", \"mesh.seat.mesh-controller.tool.plans\", \"mesh.events.dead.>\", \"mesh.again.>\"] }\n        subscribe: { allow: [\"$JS.API.>\", \"$JS.EVENT.ADVISORY.CONSUMER.MAX_DELIVERIES.>\", \"$JS.EVENT.ADVISORY.CONSUMER.DELETED.>\", \"_DELIVER.controller\", \"_DELIVER.controller.>\", \"_INBOX.controller.>\", \"mesh.control.>\", \"mesh.mod.*.event.provisioner.failing\", \"mesh.mod.*.event.provisioner.recovered\", \"mesh.mod.*.event.provisioner.retirement\", \"mesh.mod.gitea.event.pull.merged\", \"mesh.mod.gitea.event.pull.updated\", \"mesh.mod.mesh-catalog.event.catching-up\", \"mesh.mod.mesh-catalog.event.upgraded\", \"mesh.seat.mesh-build-machine.event.built\", \"mesh.seat.node-build-agent.event.built\", \"mesh.seat.operator-channel.event.decided.mesh-controller\", \"mesh.seat.mesh-controller.tool.>\", \"$SRV.PING\", \"$SRV.INFO\", \"$SRV.PING.mesh-controller\", \"$SRV.PING.mesh-controller.>\", \"$SRV.INFO.mesh-controller\", \"$SRV.INFO.mesh-controller.>\", \"$SRV.STATS\", \"$SRV.STATS.mesh-controller\", \"$SRV.STATS.mesh-controller.>\"] }\n        allow_responses: { max: 1, ttl: \"1m\" }\n      } }\n    ]\n  }\n}\n"
     },
     {
       "id": "broker",

testdata/beside/mesh-host/internal/apply/placement_guard.go.captured

@@ -31,6 +31,13 @@ package apply
 //  5. **A mount source that is a refused directory or a refused access is refused with it**: the container
 //     would otherwise bind the very path the engine would not place, and the runtime creates a missing one
 //     as root.
+//  6. **A file is judged as a directory is** (novox/hq issue 495): never one of the machine's own roots, nor
+//     in a tree nothing is placed in (rule 2), and never below a directory or an access refused here. A file
+//     or an archive below a refused path is refused with it, whichever module declares it and in whatever
+//     order. Rules 3 and 4 are a directory's owner and do not reach a file: a file below /etc is the mesh's
+//     ordinary configuration, and one below a home is judged by home_links.go and agent_home_guard.go.
+//     A refused directory also gates the rest of its module, as a step that did not complete does
+//     (apply.go's `gated`): what a module declares after its directory was written for that directory.
 //
 // Each is a failed resource with its reason in the node's report; nothing is touched. Paths are judged as
 // declared and again with every link in them resolved, so a link at /srv/x pointing at /etc places nothing.
@@ -400,6 +407,7 @@ const (
 	placingDirectory placing = iota
 	placingAccess
 	placingMount
+	placingFile
 )
 
 // refusePath says why a path is not placed or mounted; nil when it may be. module is the resource's module,
@@ -466,7 +474,7 @@ func refuseOne(path string, kind placing, module, owner string) *PlacementRefuse
 	for _, part := range strings.Split(path, "/") {
 		ssh = ssh || part == ".ssh"
 	}
-	if ssh && kind != placingDirectory {
+	if ssh && (kind == placingAccess || kind == placingMount) {
 		return &PlacementRefusedError{Path: path, Why: "it is an account's .ssh, which holds its keys and who may " +
 			"log in as it, and is never an access or a mount"}
 	}
@@ -502,8 +510,12 @@ func moduleOfID(id string) string {
 	return module
 }
 
-// refusedPlaces judges every directory and access of a declaration before anything is applied, and answers
-// each refusal by path: what is refused is refused again as a container's mount source.
+// refusedPlaces judges every directory, access, file and archive of a declaration before anything is applied,
+// and answers each refusal by path: what is refused is refused again as a container's mount source.
+//
+// Directories and accesses first, so a file or an archive below one of them is refused with it whatever order
+// they are declared in (novox/hq issue 495): the engine refused Docker's data root as a directory and then wrote
+// a file into it, because nothing judged the file's path.
 func refusedPlaces(resources []declaration.Resource) map[string]error {
 	out := map[string]error{}
 	for _, r := range resources {
@@ -520,9 +532,60 @@ func refusedPlaces(resources []declaration.Resource) map[string]error {
 			out[filepath.Clean(r.Target())] = err
 		}
 	}
+	trees := make(map[string]error, len(out))
+	for path, err := range out {
+		trees[path] = err
+	}
+	for _, r := range resources {
+		var err error
+		switch res := r.(type) {
+		case *declaration.File:
+			if err = belowRefused(res.Path, trees); err == nil {
+				err = refusePath(res.Path, placingFile, moduleOfID(res.ID), "")
+			}
+		case *declaration.Archive:
+			// Only below a refused path: where an archive may unpack is otherwise the archive's own judgement
+			// (archive.go), and the engine's own module unpacks its versions into its own tree.
+			err = belowRefused(res.Path, trees)
+		default:
+			continue
+		}
+		if err != nil {
+			out[filepath.Clean(r.Target())] = err
+		}
+	}
 	return out
 }
 
+// belowRefused says why a path below a refused directory or access is refused with it; nil when it is below
+// none. Judged as declared and with its links resolved, as refusePath judges.
+func belowRefused(path string, refused map[string]error) error {
+	clean := filepath.Clean(path)
+	if !filepath.IsAbs(clean) {
+		return nil
+	}
+	for _, p := range []string{clean, resolved(clean)} {
+		// The deepest refused tree it is below, so the same declaration always gives the same reason.
+		var tree string
+		for t := range refused {
+			if below(p, t) && len(t) > len(tree) {
+				tree = t
+			}
+		}
+		if tree == "" {
+			continue
+		}
+		why := refused[tree]
+		reason := why.Error()
+		var refusal *PlacementRefusedError
+		if errors.As(why, &refusal) {
+			reason = refusal.Why
+		}
+		return &PlacementRefusedError{Path: clean, Why: "it is below " + tree + ", which is refused: " + reason}
+	}
+	return nil
+}
+
 // refuseMounts says why a container's mounts are not made; nil when they may be.
 func refuseMounts(c *declaration.Container, refused map[string]error) error {
 	for _, v := range c.Volumes {