Admit a port from the machine's own local network, and never a public subnet (issue 154, ADR 0340)

A local service could only be declared public, which says the internet. local-network is a source and a reach: the private network and the private networks the machine reported on a link facing outside, judged here, shown by plan and node, and said in the rule set when there are none.

cmd/mesh-controller/adoption.go

@@ -722,7 +722,7 @@ func converge(ctx context.Context, open *stores, node string, yes bool, digest s
 		return "", err
 	}
 	derived := derivedFilter{rules: rules, foundation: with.Foundation, mesh: with.Mesh,
-		outward: plan.PublicDomain != "", outwardLinks: with.OutwardLinks}
+		outward: plan.PublicDomain != "", outwardLinks: with.OutwardLinks, local: with.LocalNetworks}
 	filtering, err := inv.FilteringOf(ctx, node)
 	if err != nil {
 		return "", err
@@ -930,6 +930,9 @@ type derivedFilter struct {
 	// The filter constrains what arrives on them; everything arriving elsewhere is this machine's
 	// own guest and is not filtered.
 	outwardLinks []string
+	// local is the machine's local networks, which a port from `local-network` stays open to (novox/hq
+	// ADR 0340).
+	local []string
 }
 
 // closesOutside is what a narrowing from everywhere to the private network is called: it closes.
@@ -977,6 +980,17 @@ func (d derivedFilter) fate(r inventory.Reach) string {
 			if !onMesh {
 				return fmt.Sprintf("%s — declared by %s from the mesh only", closesOutside, by)
 			}
+		case catalogue.FromLocalNetwork:
+			// The private network and this machine's local networks (novox/hq ADR 0340): it closes to
+			// everything else outside, and says which local networks stay.
+			if !onMesh {
+				if len(d.local) == 0 {
+					return fmt.Sprintf("%s — declared by %s from the local network, and this machine "+
+						"reported none", closesOutside, by)
+				}
+				return fmt.Sprintf("WILL CLOSE to everything outside the private network and %s — declared "+
+					"by %s from the local network", strings.Join(d.local, ", "), by)
+			}
 		}
 		return fmt.Sprintf("declared by %s (from %s)", by, rule.From)
 	}

cmd/mesh-controller/local_network.go

@@ -0,0 +1,67 @@
+package main
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/overlay"
+)
+
+// localNetworksOf is a machine's attached networks judged (novox/hq ADR 0340): which count as its local
+// network, from what it last said of itself and the links it said face outside it. A machine that has
+// said none judges to nothing, and a port reached from `local-network` is then admitted from the private
+// network only, and said so.
+func localNetworksOf(ctx context.Context, inv *inventory.Inventory, node string) ([]catalogue.LocalNetwork, error) {
+	account, had, err := inv.MachineOf(ctx, node)
+	if err != nil {
+		return nil, err
+	}
+	outward, err := inv.OutwardLinksOf(ctx, node)
+	if err != nil {
+		return nil, err
+	}
+	return judgedNetworks(account, had, outward, overlay.Interface), nil
+}
+
+// judgedNetworks is the judging alone, from what was read.
+func judgedNetworks(account inventory.MachineAccount, had bool, outward []string, tunnel string) []catalogue.LocalNetwork {
+	if !had || account.Machine == nil {
+		return nil
+	}
+	attached := make([]catalogue.AttachedNetwork, 0, len(account.Machine.Networks))
+	for _, n := range account.Machine.Networks {
+		attached = append(attached, catalogue.AttachedNetwork{Link: n.Link, Network: n.Network})
+	}
+	return catalogue.JudgeLocalNetworks(attached, outward, tunnel)
+}
+
+// localNetworkLines is what `node` shows of a machine's attached networks (ADR 0340 §8): each one, with
+// whether it counts as the local network and why, or why none is shown.
+func localNetworkLines(account inventory.MachineAccount, had bool, judged []catalogue.LocalNetwork) []string {
+	out := []string{"  its local network (what a port reached from local-network is admitted from):"}
+	switch {
+	case !had || account.Machine == nil:
+		return append(out, "    not said — this machine has not reported what it is attached to")
+	case len(account.Machine.Networks) == 0:
+		why := account.Machine.Unknown["networks"]
+		if why == "" {
+			why = "its node-engine is older than the one that says it"
+		}
+		return append(out, "    not said — "+why)
+	}
+	counted := 0
+	for _, j := range judged {
+		verdict := "not counted"
+		if j.Counts {
+			verdict = "counts"
+			counted++
+		}
+		out = append(out, fmt.Sprintf("    %-22s on %-10s %s: %s", j.Network, j.Link, verdict, j.Why))
+	}
+	if counted == 0 {
+		out = append(out, "    none counts: a port reached from local-network is admitted from the private network only")
+	}
+	return out
+}

cmd/mesh-controller/local_network_test.go

@@ -0,0 +1,65 @@
+package main
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/inventory"
+)
+
+// **node shows what the local network resolved to** (novox/hq ADR 0340 §8): every attached network,
+// whether it counts, and why the others do not — the public subnet named as never counted.
+func TestNodeShowsWhichAttachedNetworksCountAndWhy(t *testing.T) {
+	account := inventory.MachineAccount{Architecture: "amd64", Kernel: "linux", Machine: &inventory.MadeOf{
+		Networks: []inventory.AttachedNetwork{
+			{Link: "eth0", Network: "192.168.1.10/24"},
+			{Link: "eth1", Network: "203.0.113.7/24"},
+			{Link: "wg-mesh", Network: "10.10.0.4/24"},
+		}}}
+	judged := judgedNetworks(account, true, []string{"eth0", "eth1"}, "wg-mesh")
+	text := strings.Join(localNetworkLines(account, true, judged), "\n")
+	for _, want := range []string{
+		"192.168.1.0/24", "counts: in a private range (RFC 1918, 192.168.0.0/16)",
+		"203.0.113.0/24", "not counted: public, never counted",
+		"10.10.0.0/24", "the private network's own link",
+	} {
+		if !strings.Contains(text, want) {
+			t.Errorf("node does not say %q:\n%s", want, text)
+		}
+	}
+}
+
+// A machine that said none, or whose node-engine is older, is said as that — never as an empty list
+// that reads like a machine on no network.
+func TestNodeSaysWhenNoNetworkWasSaid(t *testing.T) {
+	older := inventory.MachineAccount{Machine: &inventory.MadeOf{}}
+	if text := strings.Join(localNetworkLines(older, true, nil), "\n"); !strings.Contains(text, "older than the one that says it") {
+		t.Errorf("an older node-engine is not said:\n%s", text)
+	}
+	public := inventory.MachineAccount{Machine: &inventory.MadeOf{
+		Networks: []inventory.AttachedNetwork{{Link: "eth0", Network: "198.51.100.9/24"}}}}
+	judged := judgedNetworks(public, true, []string{"eth0"}, "wg-mesh")
+	if text := strings.Join(localNetworkLines(public, true, judged), "\n"); !strings.Contains(text, "none counts") {
+		t.Errorf("a machine on a public network only is not said to have no local network:\n%s", text)
+	}
+	if text := strings.Join(localNetworkLines(inventory.MachineAccount{}, false, nil), "\n"); !strings.Contains(text, "not said") {
+		t.Errorf("a machine that never reported is not said:\n%s", text)
+	}
+}
+
+// The preview of a flip says what a port from the local network keeps: the local networks it stays
+// open to, or that the machine reported none (ADR 0340 §6).
+func TestTheFlipPreviewSaysWhatALocalNetworkPortKeeps(t *testing.T) {
+	rules := []catalogue.Rule{{Port: 1883, Protocol: "tcp", From: catalogue.FromLocalNetwork, Because: []string{"mosquitto"}}}
+	at := inventory.Reach{Protocol: "tcp", Address: "0.0.0.0", Port: 1883}
+	with := derivedFilter{rules: rules, mesh: []string{"10.10.0.1"}, outwardLinks: []string{"eth0"},
+		local: []string{"192.168.1.0/24"}}
+	if fate := with.fate(at); !strings.Contains(fate, "192.168.1.0/24") {
+		t.Errorf("the preview says %q, without the local network it stays open to", fate)
+	}
+	with.local = nil
+	if fate := with.fate(at); !strings.Contains(fate, "reported none") {
+		t.Errorf("the preview says %q, without saying no local network was reported", fate)
+	}
+}

cmd/mesh-controller/nodes.go

@@ -19,6 +19,7 @@ import (
 	"github.com/novox/mesh-controller/internal/conditions"
 	"github.com/novox/mesh-controller/internal/inventory"
 	"github.com/novox/mesh-controller/internal/link"
+	"github.com/novox/mesh-controller/internal/overlay"
 	"github.com/novox/mesh-controller/internal/token"
 )
 
@@ -884,6 +885,16 @@ func showNode(ctx context.Context, stored *stores, name string) error {
 		for _, line := range machineLines(account, had, time.Now()) {
 			fmt.Println(line)
 		}
+		// And which of the networks it is attached to count as its local network, and why the others
+		// do not (novox/hq ADR 0340 §8).
+		outward, err := inv.OutwardLinksOf(ctx, name)
+		if err != nil {
+			fmt.Printf("  its local network could NOT be judged: %v\n", err)
+		} else {
+			for _, line := range localNetworkLines(account, had, judgedNetworks(account, had, outward, overlay.Interface)) {
+				fmt.Println(line)
+			}
+		}
 	}
 
 	held, err := inv.Profile(ctx, name)

cmd/mesh-controller/plan.go

@@ -442,6 +442,12 @@ func declarationWith(ctx context.Context, open *stores, node string,
 	if err != nil {
 		return sendable{}, err
 	}
+	// Which ports the filter admits from the local network, and from which networks, for plan to say
+	// (novox/hq ADR 0340 §8). The same rules the composition rendered, never sent.
+	rules, err := plan.Rules(with)
+	if err != nil {
+		return sendable{}, err
+	}
 	// And what was taken on it, said in every declaration it is sent from this one place.
 	adoption, err := adoptionOf(ctx, open.inventory, record, plan, composed)
 	if err != nil {
@@ -451,7 +457,8 @@ func declarationWith(ctx context.Context, open *stores, node string,
 		Received: composed.Received, Mesh: with.Mesh, BusUsers: with.BusUsers,
 		LeftOut: sortedKeysOf(composed.LeftOut), leftOutWhy: composed.LeftOut, withheld: with.Withheld,
 		unbound: with.Unbound, foreseen: composed.Foreseen, unplaced: composed.Unplaced,
-		modules: namedModules(plan, composed.LeftOut)}
+		modules:      namedModules(plan, composed.LeftOut),
+		localNetwork: catalogue.LocalNetworkPorts(rules, with.LocalNetworks)}
 	// And which build of each module it carries, for the send to record (novox/hq issue 259, ADR
 	// 0221). Read only on the send path: a question about what would be sent records nothing.
 	if choosing == Allocating {
@@ -960,6 +967,12 @@ func renderingFor(ctx context.Context, open *stores, node string,
 	if err != nil {
 		return catalogue.Rendering{}, inventory.Node{}, err
 	}
+	// And which of the networks it is attached to count as its local network (novox/hq ADR 0340):
+	// private ranges only, on a link facing outside it. Reported by the machine, never set.
+	local, err := localNetworksOf(ctx, inv, node)
+	if err != nil {
+		return catalogue.Rendering{}, inventory.Node{}, err
+	}
 	// Where this machine reaches each mesh seat's holder, for ${seat:<seat>:reach} (novox/hq ADR
 	// 0222): the artifact store as this network reaches it, which the container runtime is told to
 	// trust (ADR 0082). The same address composed into every reference the mesh built.
@@ -984,7 +997,8 @@ func renderingFor(ctx context.Context, open *stores, node string,
 		Machines: machines, Zones: zones, Holders: replicas,
 		Suffix: overlay.Suffix(), MeshRange: meshRange, TunnelInterface: overlay.Interface, Accounts: accounts, Foundation: foundation,
 		Kept: kept, Adopted: record.Adopted, OutwardLinks: outwardLinks,
-		Given: given, Taken: taken, Seats: seats, ArtifactStore: artifactStore, SeatReach: reach, Built: built,
+		LocalNetworks: catalogue.CountedLocalNetworks(local),
+		Given:         given, Taken: taken, Seats: seats, ArtifactStore: artifactStore, SeatReach: reach, Built: built,
 		BusUsers: busUsers, Withheld: withheld, Unbound: unbound,
 	}, record, nil
 }
@@ -1417,6 +1431,11 @@ func planCommand(ctx context.Context, args []string) error {
 			fmt.Printf("  %-20s settings from %s\n", module, layer.From)
 		}
 	}
+	// What each port reached from the local network resolved to on this machine (novox/hq ADR 0340 §8),
+	// or that it resolved to none.
+	for _, p := range declared.localNetwork {
+		fmt.Println("  " + p.Said())
+	}
 	fmt.Printf("\n%d resource(s)\n", len(resources))
 
 	if *show {

cmd/mesh-controller/sendable.go

@@ -40,6 +40,9 @@ type sendable struct {
 	actingEpoch  uint64
 	// modules are the modules this declaration names, for the record of the send; never on the wire.
 	modules []string
+	// localNetwork is every port admitted from the local network and what it resolved to (novox/hq ADR
+	// 0340 §8), for plan to say; never on the wire.
+	localNetwork []catalogue.LocalNetworkPort
 	// Adoption is nil for a converged node, and then the body is byte for byte what it was before
 	// adoption existed: an older host parses the envelope strictly and would refuse the key.
 	Adoption *adoptionEnvelope