feat(samba): settings registry + smb.conf/compose renderers (R-7 slice 1, Part 1)

SMBSettings + SMBShare registry in settings (password never stored — only UserSet); NetBIOS-safe name validation. Pure infra renderers: RenderSambaConfig (hardened global block: SMB2 floor, bind interfaces only=lo eth0, disable netbios=no, force user block) + RenderSambaCompose (network_mode host, pinned image, :ro bind for read-only shares, passdb volume). Exact smb.conf golden + CRUD/validation tests.
2026-07-18 11:21:05 +02:00
parent f42f3e0e08
commit b0c5ef4823
6 changed files with 568 additions and 0 deletions
@@ -0,0 +1,115 @@
+package infra
+
+import (
+	"fmt"
+	"sort"
+	"strings"
+)
+
+// Samba (LAN network-sharing) renderers — R-7 slice 1. PURE like the rest of this package: share
+// list in, file contents out; no docker, no filesystem. The orchestration (availability filtering,
+// write, compose up, smbpasswd) lives in internal/stacks/samba.go (ReconcileSamba). The transport +
+// daemon set are the R-6 spike verdict (SPIKE-lan-discovery-2026-07-18): host network, smbd + nmbd +
+// wsdd, `bind interfaces only` on lo+eth0.
+
+// SambaShareRender is one exported folder as the renderer needs it (already availability-filtered by
+// the caller — a dead-mount share is simply absent from the slice, never rendered).
+type SambaShareRender struct {
+	Name     string
+	Path     string // absolute host path
+	ReadOnly bool
+}
+
+// SambaData is the full input for both samba renderers.
+type SambaData struct {
+	ServerName string // NetBIOS name (validated by the settings layer)
+	Shares     []SambaShareRender
+	UID        int // household uid/gid the container runs shares as (1000)
+}
+
+// SambaHouseholdUser is the single household SMB account name (matches the entrypoint's unix user).
+const SambaHouseholdUser = "felhom"
+
+// RenderSambaConfig renders smb.conf: the hardened global block (bind interfaces only = lo eth0,
+// SMB2+ floor, NetBIOS on for flat-name resolution) plus one [section] per share. Deterministic:
+// shares are emitted in the given order (the caller preserves registry order). force user/group pin
+// every written file to the household uid so apps and both backup tiers see consistent ownership.
+func RenderSambaConfig(d SambaData) string {
+	var b strings.Builder
+	b.WriteString("# Samba (LAN network-sharing) — managed by felhom-controller (R-7).\n")
+	b.WriteString("# WARNING: auto-generated. Manual edits are overwritten on the next share change.\n")
+	b.WriteString("[global]\n")
+	b.WriteString("  workgroup = WORKGROUP\n")
+	b.WriteString("  server string = Felhom hálózati megosztás\n")
+	fmt.Fprintf(&b, "  netbios name = %s\n", d.ServerName)
+	b.WriteString("  security = user\n")
+	b.WriteString("  map to guest = never\n")
+	b.WriteString("  server min protocol = SMB2\n")
+	b.WriteString("  disable netbios = no\n")
+	b.WriteString("  bind interfaces only = yes\n")
+	b.WriteString("  interfaces = lo eth0\n")
+	b.WriteString("  smb ports = 445\n")
+	b.WriteString("  load printers = no\n")
+	b.WriteString("  printing = bsd\n")
+	b.WriteString("  printcap name = /dev/null\n")
+	b.WriteString("  disable spoolss = yes\n")
+
+	for _, sh := range d.Shares {
+		ro := "no"
+		if sh.ReadOnly {
+			ro = "yes"
+		}
+		fmt.Fprintf(&b, "\n[%s]\n", sh.Name)
+		fmt.Fprintf(&b, "  path = %s\n", sh.Path)
+		fmt.Fprintf(&b, "  read only = %s\n", ro)
+		fmt.Fprintf(&b, "  valid users = %s\n", SambaHouseholdUser)
+		fmt.Fprintf(&b, "  force user = %s\n", SambaHouseholdUser)
+		fmt.Fprintf(&b, "  force group = %s\n", SambaHouseholdUser)
+		b.WriteString("  create mask = 0644\n")
+		b.WriteString("  directory mask = 0755\n")
+	}
+	return b.String()
+}
+
+// RenderSambaCompose renders the samba stack's docker-compose.yml: host network (the spike mandate —
+// the default bridge is deaf to LAN multicast), the pinned image, smb.conf bind-mounted read-only,
+// the passdb named volume, and one bind per share (:ro for read-only shares — defense in depth beside
+// the smb.conf-level `read only`). Deterministic: share binds are sorted so the output is stable.
+func RenderSambaCompose(d SambaData) string {
+	shares := make([]SambaShareRender, len(d.Shares))
+	copy(shares, d.Shares)
+	sort.Slice(shares, func(i, j int) bool { return shares[i].Path < shares[j].Path })
+
+	var binds strings.Builder
+	for _, sh := range shares {
+		if sh.ReadOnly {
+			fmt.Fprintf(&binds, "      - %s:%s:ro\n", sh.Path, sh.Path)
+		} else {
+			fmt.Fprintf(&binds, "      - %s:%s\n", sh.Path, sh.Path)
+		}
+	}
+
+	return fmt.Sprintf(`# Samba (LAN network-sharing) — managed by felhom-controller (R-7 slice 1).
+# WARNING: auto-generated. Manual edits are overwritten on the next share change.
+# Host network is REQUIRED (SPIKE-lan-discovery-2026-07-18): the default docker bridge cannot
+# receive the LAN multicast that WSD/mDNS discovery needs.
+
+services:
+  felhom-samba:
+    image: %s
+    container_name: felhom-samba
+    restart: unless-stopped
+    network_mode: host
+    environment:
+      - FELHOM_SERVER_NAME=%s
+      - FELHOM_IFACE=eth0
+      - FELHOM_UID=%d
+      - FELHOM_GID=%d
+    volumes:
+      - ./smb.conf:/etc/samba/smb.conf:ro
+      - samba-passdb:/var/lib/samba
+%s
+volumes:
+  samba-passdb:
+`, SambaImage, d.ServerName, d.UID, d.UID, binds.String())
+}