rollcall/cmd/rollcall/netapi.go

package main

// HTTP API and CLI for the network model and rack controllers.

import (
	"encoding/json"
	"errors"
	"fmt"
	"net"
	"net/http"
	"os"
	"strconv"
	"strings"
)

// ---------------------------------------------------------------- HTTP

func (a *App) netChanged(r *http.Request) {
	a.reloadNet(r.Context())
	a.hub.bump()
}

func (a *App) handleFabrics(w http.ResponseWriter, r *http.Request) {
	if r.Method == http.MethodGet {
		fs, err := a.store.Fabrics(r.Context())
		if err != nil {
			fail(w, 500, err)
			return
		}
		writeJSON(w, 200, fs)
		return
	}
	var f Fabric
	if err := json.NewDecoder(r.Body).Decode(&f); err != nil || !tagNameRe.MatchString(f.Name) {
		fail(w, 400, errors.New("name is required: lowercase letters, digits, . _ -"))
		return
	}
	if f.Kind != "" && f.Kind != "ethernet" && f.Kind != "infiniband" {
		fail(w, 400, errors.New("kind is ethernet or infiniband"))
		return
	}
	if err := a.store.PutFabric(r.Context(), f); err != nil {
		fail(w, 500, err)
		return
	}
	a.netChanged(r)
	writeJSON(w, 200, f)
}

func (a *App) handleFabricDelete(w http.ResponseWriter, r *http.Request) {
	if err := a.store.DeleteFabric(r.Context(), r.PathValue("name")); err != nil {
		fail(w, 500, err)
		return
	}
	a.netChanged(r)
	writeJSON(w, 200, obj{"deleted": r.PathValue("name")})
}

func (a *App) handleVLANs(w http.ResponseWriter, r *http.Request) {
	if r.Method == http.MethodGet {
		vs, err := a.store.VLANs(r.Context())
		if err != nil {
			fail(w, 500, err)
			return
		}
		writeJSON(w, 200, vs)
		return
	}
	var v VLAN
	if err := json.NewDecoder(r.Body).Decode(&v); err != nil || v.Fabric == "" || v.VID < 0 || v.VID > 4094 && v.VID < 0x8000 {
		fail(w, 400, errors.New("fabric and vid (0 untagged, 1-4094, or an IB pkey) are required"))
		return
	}
	if v.DHCPMode == "proxy" {
		v.DHCP = true
	} else if v.DHCPMode != "" && v.DHCPMode != "serve" {
		fail(w, 400, fmt.Errorf("dhcp_mode %q: serve or proxy", v.DHCPMode))
		return
	}
	if v.DHCP && v.PrimaryRack == "" {
		v.PrimaryRack = a.cfg.RackName
	}
	racks := a.racksSnapshot()
	for _, rk := range []string{v.PrimaryRack, v.SecondaryRack} {
		if _, ok := racks[rk]; rk != "" && !ok {
			fail(w, 400, fmt.Errorf("rack controller %s is not registered", rk))
			return
		}
	}
	id, err := a.store.PutVLAN(r.Context(), v)
	if err != nil {
		fail(w, 500, err)
		return
	}
	v.ID = id
	a.netChanged(r)
	writeJSON(w, 200, v)
}

func (a *App) handleVLANDelete(w http.ResponseWriter, r *http.Request) {
	vid, _ := strconv.Atoi(r.PathValue("vid"))
	if err := a.store.DeleteVLAN(r.Context(), r.PathValue("fabric"), vid); err != nil {
		fail(w, 500, err)
		return
	}
	a.netChanged(r)
	writeJSON(w, 200, obj{"deleted": fmt.Sprintf("%s/%d", r.PathValue("fabric"), vid)})
}

func (a *App) handleSubnets(w http.ResponseWriter, r *http.Request) {
	if r.Method == http.MethodGet {
		ss, err := a.store.Subnets(r.Context())
		if err != nil {
			fail(w, 500, err)
			return
		}
		writeJSON(w, 200, ss)
		return
	}
	var sn Subnet
	if err := json.NewDecoder(r.Body).Decode(&sn); err != nil {
		fail(w, 400, err)
		return
	}
	_, n, err := net.ParseCIDR(sn.CIDR)
	if err != nil {
		fail(w, 400, errors.New("cidr must be a network, e.g. 10.0.0.0/24 or fd00:1::/64"))
		return
	}
	sn.CIDR = n.String()
	if familyOf(sn.CIDR) == 6 {
		if ones, _ := n.Mask.Size(); ones > 126 {
			fail(w, 400, errors.New("an IPv6 subnet needs room: /126 or shorter (/64 is usual)"))
			return
		}
	}
	if sn.Gateway != "" && !sn.contains(sn.Gateway) {
		fail(w, 400, fmt.Errorf("gateway %s is outside %s", sn.Gateway, sn.CIDR))
		return
	}
	switch sn.Purpose {
	case "", "provisioning", "mgmt", "bmc", "storage", "ib", "other":
	default:
		fail(w, 400, errors.New("purpose is provisioning, mgmt, bmc, storage, ib or other"))
		return
	}
	if sn.Fabric != "" && sn.VLANID == 0 {
		vs, _ := a.store.VLANs(r.Context())
		for _, v := range vs {
			if v.Fabric == sn.Fabric && v.VID == sn.VID {
				sn.VLANID = v.ID
			}
		}
		if sn.VLANID == 0 { // a subnet on a VLAN not declared yet: create it
			fs, _ := a.store.Fabrics(r.Context())
			known := false
			for _, f := range fs {
				known = known || f.Name == sn.Fabric
			}
			if !known {
				fail(w, 400, fmt.Errorf("fabric %s does not exist", sn.Fabric))
				return
			}
			if sn.VLANID, err = a.store.PutVLAN(r.Context(), VLAN{Fabric: sn.Fabric, VID: sn.VID}); err != nil {
				fail(w, 500, err)
				return
			}
		}
	}
	for _, other := range a.subnetsSnapshot() {
		if other.CIDR == sn.CIDR {
			continue
		}
		if _, on, err := net.ParseCIDR(other.CIDR); err == nil && (on.Contains(n.IP) || n.Contains(on.IP)) {
			fail(w, 409, fmt.Errorf("%s overlaps %s", sn.CIDR, other.CIDR))
			return
		}
	}
	if err := a.store.PutSubnet(r.Context(), sn); err != nil {
		fail(w, 500, err)
		return
	}
	a.adoptIPs(r.Context())
	a.netChanged(r)
	writeJSON(w, 200, sn)
}

func (a *App) handleSubnetDelete(w http.ResponseWriter, r *http.Request) {
	cidr := r.PathValue("cidr")
	if ips, _ := a.store.IPs(r.Context(), cidr, ""); len(ips) > 0 && r.URL.Query().Get("force") != "1" {
		fail(w, 409, fmt.Errorf("%s still has %d address(es) handed out (force=1 drops them)", cidr, len(ips)))
		return
	}
	if err := a.store.DeleteSubnet(r.Context(), cidr); err != nil {
		fail(w, 500, err)
		return
	}
	a.netChanged(r)
	writeJSON(w, 200, obj{"deleted": cidr})
}

func (a *App) handleRanges(w http.ResponseWriter, r *http.Request) {
	var rg IPRange
	if err := json.NewDecoder(r.Body).Decode(&rg); err != nil {
		fail(w, 400, err)
		return
	}
	if rg.Kind != "dynamic" && rg.Kind != "reserved" && rg.Kind != "static" {
		fail(w, 400, errors.New("kind is dynamic, reserved or static"))
		return
	}
	sn := subnetByRef(a.subnetsSnapshot(), rg.Subnet)
	if sn == nil {
		fail(w, 404, fmt.Errorf("subnet %s: %w", rg.Subnet, errSubnetUnknown))
		return
	}
	lo, ok1 := parseAddr(rg.Start)
	hi, ok2 := parseAddr(rg.End)
	if !ok1 || !ok2 || hi.Less(lo) || !sn.contains(rg.Start) || !sn.contains(rg.End) {
		fail(w, 400, fmt.Errorf("range %s-%s is not inside %s", rg.Start, rg.End, sn.CIDR))
		return
	}
	rg.Start, rg.End = lo.String(), hi.String()
	for _, o := range sn.Ranges {
		ol, _ := parseAddr(o.Start)
		oh, _ := parseAddr(o.End)
		if !oh.Less(lo) && !hi.Less(ol) {
			fail(w, 409, fmt.Errorf("overlaps the %s range %s-%s", o.Kind, o.Start, o.End))
			return
		}
	}
	rg.Subnet = sn.CIDR
	id, err := a.store.AddRange(r.Context(), rg)
	if err != nil {
		fail(w, 500, err)
		return
	}
	rg.ID = id
	a.netChanged(r)
	writeJSON(w, 200, rg)
}

func (a *App) handleRangeDelete(w http.ResponseWriter, r *http.Request) {
	id, _ := strconv.ParseInt(r.PathValue("id"), 10, 64)
	if err := a.store.DeleteRange(r.Context(), id); err != nil {
		fail(w, 500, err)
		return
	}
	a.netChanged(r)
	writeJSON(w, 200, obj{"deleted": id})
}

func (a *App) handleIPs(w http.ResponseWriter, r *http.Request) {
	switch r.Method {
	case http.MethodGet:
		ips, err := a.store.IPs(r.Context(), r.URL.Query().Get("subnet"), r.URL.Query().Get("machine"))
		if err != nil {
			fail(w, 500, err)
			return
		}
		writeJSON(w, 200, ips)
	case http.MethodPost: // reserve one address (a switch, a PDU, a VIP)
		var x IPAddr
		if err := json.NewDecoder(r.Body).Decode(&x); err != nil {
			fail(w, 400, err)
			return
		}
		sn := subnetFor(a.subnetsSnapshot(), x.IP)
		if sn == nil {
			fail(w, 404, fmt.Errorf("%s is in no subnet", x.IP))
			return
		}
		ok, err := a.claimIP(r.Context(), IPAddr{IP: x.IP, Subnet: sn.CIDR, Kind: "reserved", Hostname: x.Hostname})
		if err != nil {
			fail(w, 500, err)
			return
		}
		if !ok {
			fail(w, 409, fmt.Errorf("%s is taken", x.IP))
			return
		}
		a.netChanged(r)
		writeJSON(w, 200, obj{"reserved": x.IP, "subnet": sn.CIDR})
	}
}

func (a *App) handleIPDelete(w http.ResponseWriter, r *http.Request) {
	if err := a.store.ReleaseIP(r.Context(), r.PathValue("ip")); err != nil {
		fail(w, 500, err)
		return
	}
	a.kickIPAM()
	a.netChanged(r)
	writeJSON(w, 200, obj{"released": r.PathValue("ip")})
}

func validLayout(l NetLayout) error {
	if !tagNameRe.MatchString(l.Name) {
		return errors.New("name is required: lowercase letters, digits, . _ -")
	}
	if len(l.Interfaces) == 0 {
		return errors.New("a layout needs at least one interface")
	}
	names := map[string]bool{}
	for _, i := range l.Interfaces {
		switch i.Type {
		case "", "physical":
		case "bond":
			if len(i.Members) == 0 {
				return fmt.Errorf("bond %s has no members", i.Name)
			}
		case "vlan":
			if !names[i.Parent] || i.VID < 1 || i.VID > 4094 {
				return fmt.Errorf("vlan %q needs a parent defined above it and a vid 1-4094", i.Name)
			}
		default:
			return fmt.Errorf("interface type %q: physical, bond or vlan", i.Type)
		}
		for _, lk := range i.Links {
			switch lk.Mode {
			case "", "auto", "static", "dhcp", "link_up":
			default:
				return fmt.Errorf("link mode %q: auto, static, dhcp or link_up", lk.Mode)
			}
		}
		n := i.Name
		if n == "" && i.Type == "vlan" {
			n = fmt.Sprintf("%s.%d", i.Parent, i.VID)
		}
		names[n] = true
	}
	return nil
}

func (a *App) handleLayouts(w http.ResponseWriter, r *http.Request) {
	if r.Method == http.MethodGet {
		ls, err := a.store.Layouts(r.Context())
		if err != nil {
			fail(w, 500, err)
			return
		}
		ms, _ := a.store.List(r.Context())
		for i := range ls {
			for _, m := range ms {
				if l, _ := a.layoutFor(r.Context(), m); l != nil && strings.HasPrefix(l.Name, ls[i].Name) {
					ls[i].Machines++
				}
			}
		}
		writeJSON(w, 200, ls)
		return
	}
	var l NetLayout
	if err := json.NewDecoder(r.Body).Decode(&l); err != nil {
		fail(w, 400, err)
		return
	}
	if err := validLayout(l); err != nil {
		fail(w, 400, err)
		return
	}
	if err := a.store.PutLayout(r.Context(), l); err != nil {
		fail(w, 500, err)
		return
	}
	writeJSON(w, 200, l)
}

func (a *App) handleLayoutDelete(w http.ResponseWriter, r *http.Request) {
	if err := a.store.DeleteLayout(r.Context(), r.PathValue("name")); err != nil {
		fail(w, 409, err)
		return
	}
	writeJSON(w, 200, obj{"deleted": r.PathValue("name")})
}

// handleMachineNetwork: GET shows the plan and the network-config it renders
// (without handing out addresses); POST sets the layout and pinned addresses.
func (a *App) handleMachineNetwork(w http.ResponseWriter, r *http.Request) {
	m, err := a.store.Get(r.Context(), r.PathValue("id"))
	if err != nil {
		fail(w, 500, err)
		return
	}
	if r.Method == http.MethodPost {
		var req struct {
			Layout   *string `json:"layout"`
			Rack     *string `json:"rack_controller"`
			Static   []struct{ Iface, IP string }
			Unstatic []string `json:"unstatic"`
		}
		if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
			fail(w, 400, err)
			return
		}
		if req.Layout != nil {
			if *req.Layout != "" {
				ls, _ := a.store.Layouts(r.Context())
				found := false
				for _, l := range ls {
					found = found || l.Name == *req.Layout
				}
				if !found {
					fail(w, 404, fmt.Errorf("layout %s does not exist", *req.Layout))
					return
				}
			}
			if err := a.store.SetMachineLayout(r.Context(), m.ID, *req.Layout); err != nil {
				fail(w, 500, err)
				return
			}
		}
		if req.Rack != nil {
			if _, ok := a.racksSnapshot()[*req.Rack]; *req.Rack != "" && !ok {
				fail(w, 404, fmt.Errorf("rack controller %s is not registered", *req.Rack))
				return
			}
			if err := a.store.SetRackController(r.Context(), m.ID, *req.Rack); err != nil {
				fail(w, 500, err)
				return
			}
			m, _ = a.store.Get(r.Context(), m.ID)
			_ = a.writePXEAny(r.Context(), m) // its PXE file moves to the new rack
		}
		for _, ip := range req.Unstatic {
			have, _ := a.store.IPs(r.Context(), "", m.ID)
			for _, x := range have {
				if x.IP == ip && x.Kind == "static" {
					_ = a.store.ReleaseIP(r.Context(), ip)
					a.kickIPAM()
				}
			}
		}
		for _, st := range req.Static {
			sn := subnetFor(a.subnetsSnapshot(), st.IP)
			if sn == nil {
				fail(w, 400, fmt.Errorf("%s is in no subnet", st.IP))
				return
			}
			have, _ := a.store.IPs(r.Context(), sn.CIDR, m.ID)
			for _, x := range have { // one pinned address per interface and subnet
				if x.Iface == st.Iface && x.IP != st.IP {
					_ = a.store.ReleaseIP(r.Context(), x.IP)
				}
			}
			if ok, err := a.claimIP(r.Context(), IPAddr{IP: st.IP, Subnet: sn.CIDR, MachineID: m.ID, Iface: st.Iface, Kind: "static", Hostname: deref(m.NodeName)}); err != nil {
				fail(w, 500, err)
				return
			} else if !ok {
				cur, _ := a.store.IPs(r.Context(), sn.CIDR, m.ID)
				mine := false
				for _, x := range cur {
					mine = mine || x.IP == st.IP
				}
				if !mine {
					fail(w, 409, fmt.Errorf("%s is taken", st.IP))
					return
				}
				_, _ = a.store.pool.Exec(r.Context(), `UPDATE ip_addresses SET kind='static', iface=$2 WHERE ip=$1`, st.IP, st.Iface)
			}
		}
		_ = a.store.AddEvent(r.Context(), m.ID, "network", fmt.Sprintf("layout=%v static=%v unstatic=%v", deref(req.Layout), req.Static, req.Unstatic))
		a.netChanged(r)
		m, _ = a.store.Get(r.Context(), m.ID)
	}
	plan, err := a.netPlan(r.Context(), m, false)
	if err != nil {
		fail(w, 409, err)
		return
	}
	ips, _ := a.store.IPs(r.Context(), "", m.ID)
	writeJSON(w, 200, obj{"id": m.ID, "layout": plan.Layout, "plan": plan, "network_config": networkConfig(plan), "addresses": ips,
		"rack_controller": a.rackOf(m), "modeled": len(a.subnetsSnapshot()) > 0})
}

// ---------------------------------------------------------------- CLI

func (c *client) netCmd(cmd string, args []string) error {
	need := func(n int) {
		if len(args) < n {
			usage()
		}
	}
	sub := ""
	if len(args) > 0 {
		sub = args[0]
	}
	switch cmd {
	case "fabric":
		switch sub {
		case "", "list":
			var fs []Fabric
			if err := c.do("GET", "/api/v1/fabrics", nil, &fs); err != nil {
				return err
			}
			fmt.Printf("%-16s %-11s %s\n", "FABRIC", "KIND", "COMMENT")
			for _, f := range fs {
				fmt.Printf("%-16s %-11s %s\n", f.Name, f.Kind, f.Comment)
			}
		case "add":
			need(2)
			fs := newFlags("fabric add")
			kind := fs.String("kind", "ethernet", "ethernet | infiniband")
			comment := fs.String("comment", "", "comment")
			_ = fs.Parse(args[2:])
			return c.do("POST", "/api/v1/fabrics", Fabric{Name: args[1], Kind: *kind, Comment: *comment}, nil)
		case "rm":
			need(2)
			return c.do("DELETE", "/api/v1/fabrics/"+args[1], nil, nil)
		default:
			usage()
		}
	case "vlan":
		switch sub {
		case "", "list":
			var vs []VLAN
			if err := c.do("GET", "/api/v1/vlans", nil, &vs); err != nil {
				return err
			}
			fmt.Printf("%-14s %5s %-14s %5s %-6s %-14s %s\n", "FABRIC", "VID", "NAME", "MTU", "DHCP", "RACK", "SECONDARY")
			for _, v := range vs {
				fmt.Printf("%-14s %5d %-14s %5d %-6s %-14s %s\n", v.Fabric, v.VID, v.Name, v.MTU, orDash(v.DHCPMode), v.PrimaryRack, v.SecondaryRack)
			}
		case "add", "set":
			need(3)
			fs := newFlags("vlan add")
			name := fs.String("name", "", "name")
			mtu := fs.Int("mtu", 1500, "MTU")
			dhcp := fs.Bool("dhcp", false, "serve DHCP/PXE on this VLAN")
			proxy := fs.Bool("proxy-dhcp", false, "another DHCP server hands out addresses here; only answer PXE (proxy DHCP)")
			rack := fs.String("rack", "", "rack controller serving it (default: the region's embedded one)")
			sec := fs.String("secondary", "", "second rack controller (the dynamic range is split)")
			_ = fs.Parse(args[3:])
			vid, _ := strconv.Atoi(args[2])
			var v VLAN
			mode := ""
			if *proxy {
				mode = "proxy"
			}
			if err := c.do("POST", "/api/v1/vlans", VLAN{Fabric: args[1], VID: vid, Name: *name, MTU: *mtu, DHCP: *dhcp || *proxy, DHCPMode: mode, PrimaryRack: *rack, SecondaryRack: *sec}, &v); err != nil {
				return err
			}
			fmt.Printf("vlan %s/%d: dhcp=%s rack=%s\n", v.Fabric, v.VID, orDash(v.DHCPMode), v.PrimaryRack)
		case "rm":
			need(3)
			return c.do("DELETE", "/api/v1/vlans/"+args[1]+"/"+args[2], nil, nil)
		default:
			usage()
		}
	case "subnet":
		switch sub {
		case "", "list":
			var ss []Subnet
			if err := c.do("GET", "/api/v1/subnets", nil, &ss); err != nil {
				return err
			}
			fmt.Printf("%-24s %-12s %-14s %-12s %-15s %-12s %9s  %s\n", "SUBNET", "PURPOSE", "FABRIC/VLAN", "DHCP RACK", "GATEWAY", "DOMAIN", "USED", "RANGES")
			for _, s := range ss {
				dhcp := "-"
				if s.DHCP {
					dhcp = s.PrimaryRack
					if s.SecondaryRack != "" {
						dhcp += "+" + s.SecondaryRack
					}
				}
				var rs []string
				for _, r := range s.Ranges {
					rs = append(rs, fmt.Sprintf("%s:%s-%s", r.Kind, r.Start, lastOctets(r.End)))
				}
				size := strconv.Itoa(s.Size)
				if s.Size == 0 {
					size = "∞"
				}
				fmt.Printf("%-24s %-12s %-14s %-12s %-15s %-12s %4d/%-4s  %s\n", s.CIDR, s.Purpose, fmt.Sprintf("%s/%d", orDash(s.Fabric), s.VID), dhcp, orDash(s.Gateway), orDash(s.Domain), s.Used, size, strings.Join(rs, " "))
			}
		case "show":
			need(2)
			var ss []Subnet
			if err := c.do("GET", "/api/v1/subnets", nil, &ss); err != nil {
				return err
			}
			for _, s := range ss {
				if s.CIDR == args[1] || s.Name == args[1] {
					fmt.Printf("%s  %s  fabric %s vlan %d mtu %d  dhcp=%v rack=%s %s\n  gateway %s  dns %v  domain %s\n", s.CIDR, s.Purpose, s.Fabric, s.VID, s.MTU, s.DHCP, s.PrimaryRack, s.SecondaryRack, orDash(s.Gateway), s.DNS, orDash(s.Domain))
					for _, r := range s.Ranges {
						fmt.Printf("  range %-4d %-8s %s - %s  %s\n", r.ID, r.Kind, r.Start, r.End, r.Comment)
					}
					var ips []IPAddr
					if err := c.do("GET", "/api/v1/ips?subnet="+s.CIDR, nil, &ips); err != nil {
						return err
					}
					fmt.Printf("  %d of %d addresses in use\n", len(ips), s.Size)
					for _, x := range ips {
						fmt.Printf("    %-15s %-8s %-16s %-10s %s\n", x.IP, x.Kind, orDash(x.MachineID), x.Iface, x.Hostname)
					}
					return nil
				}
			}
			return errNotFound
		case "add", "set":
			need(2)
			fs := newFlags("subnet add")
			fabric := fs.String("fabric", "", "fabric (the VLAN is created when missing)")
			vid := fs.Int("vid", 0, "VLAN id (0 = untagged)")
			purpose := fs.String("purpose", "provisioning", "provisioning | mgmt | bmc | storage | ib | other")
			gw := fs.String("gateway", "", "default gateway")
			dns := fs.String("dns", "", "comma-separated DNS servers")
			domain := fs.String("domain", "", "DNS domain")
			name := fs.String("name", "", "name")
			comment := fs.String("comment", "", "comment")
			_ = fs.Parse(args[2:])
			sn := Subnet{CIDR: args[1], Fabric: *fabric, VID: *vid, Purpose: *purpose, Gateway: *gw, Domain: *domain, Name: *name, Comment: *comment, DNS: []string{}}
			if *dns != "" {
				sn.DNS = strings.Split(*dns, ",")
			}
			var out Subnet
			if err := c.do("POST", "/api/v1/subnets", sn, &out); err != nil {
				return err
			}
			fmt.Printf("subnet %s saved\n", out.CIDR)
		case "rm":
			need(2)
			q := ""
			if len(args) > 2 && args[2] == "-force" {
				q = "?force=1"
			}
			return c.do("DELETE", "/api/v1/subnets/"+args[1]+q, nil, nil)
		default:
			usage()
		}
	case "range":
		switch sub {
		case "add":
			need(5)
			fs := newFlags("range add")
			comment := fs.String("comment", "", "comment")
			_ = fs.Parse(args[5:])
			var rg IPRange
			if err := c.do("POST", "/api/v1/ranges", IPRange{Subnet: args[1], Kind: args[2], Start: args[3], End: args[4], Comment: *comment}, &rg); err != nil {
				return err
			}
			fmt.Printf("range %d: %s %s-%s on %s\n", rg.ID, rg.Kind, rg.Start, rg.End, rg.Subnet)
		case "rm":
			need(2)
			return c.do("DELETE", "/api/v1/ranges/"+args[1], nil, nil)
		default:
			usage()
		}
	case "ip":
		switch sub {
		case "", "list":
			fs := newFlags("ip list")
			subnet := fs.String("subnet", "", "only this subnet")
			_ = fs.Parse(args[min(1, len(args)):])
			var ips []IPAddr
			if err := c.do("GET", "/api/v1/ips?subnet="+*subnet, nil, &ips); err != nil {
				return err
			}
			fmt.Printf("%-15s %-18s %-8s %-16s %-10s %s\n", "IP", "SUBNET", "KIND", "MACHINE", "IFACE", "HOSTNAME")
			for _, x := range ips {
				fmt.Printf("%-15s %-18s %-8s %-16s %-10s %s\n", x.IP, x.Subnet, x.Kind, orDash(x.MachineID), x.Iface, x.Hostname)
			}
		case "reserve":
			need(2)
			fs := newFlags("ip reserve")
			host := fs.String("name", "", "what it is (a switch, a VIP)")
			_ = fs.Parse(args[2:])
			return c.do("POST", "/api/v1/ips", IPAddr{IP: args[1], Hostname: *host}, nil)
		case "release":
			need(2)
			return c.do("DELETE", "/api/v1/ips/"+args[1], nil, nil)
		default:
			usage()
		}
	case "layout":
		switch sub {
		case "", "list":
			var ls []NetLayout
			if err := c.do("GET", "/api/v1/layouts", nil, &ls); err != nil {
				return err
			}
			fmt.Printf("%-18s %8s  %-50s %s\n", "LAYOUT", "MACHINES", "INTERFACES", "COMMENT")
			for _, l := range ls {
				fmt.Printf("%-18s %8d  %-50s %s\n", l.Name, l.Machines, trunc(layoutSummary(l), 50), l.Comment)
			}
		case "show":
			need(2)
			var ls []NetLayout
			if err := c.do("GET", "/api/v1/layouts", nil, &ls); err != nil {
				return err
			}
			for _, l := range ls {
				if l.Name == args[1] {
					b, _ := json.MarshalIndent(l, "", "  ")
					fmt.Println(string(b))
					return nil
				}
			}
			return errNotFound
		case "add":
			need(3)
			fs := newFlags("layout add")
			comment := fs.String("comment", "", "comment")
			_ = fs.Parse(args[3:])
			b, err := readFileArg(args[2])
			if err != nil {
				return err
			}
			var l NetLayout
			if err := json.Unmarshal(b, &l); err != nil {
				return fmt.Errorf("%s: %w", args[2], err)
			}
			l.Name = args[1]
			if *comment != "" {
				l.Comment = *comment
			}
			return c.do("POST", "/api/v1/layouts", l, nil)
		case "rm":
			need(2)
			return c.do("DELETE", "/api/v1/layouts/"+args[1], nil, nil)
		default:
			usage()
		}
	case "net":
		need(2)
		switch sub {
		case "show":
			var d obj
			if err := c.do("GET", "/api/v1/machines/"+args[1]+"/network", nil, &d); err != nil {
				return err
			}
			printNet(d)
		case "set":
			fs := newFlags("net set")
			layout := fs.String("layout", "\x00", "layout name (\"\" = from tags / default)")
			rack := fs.String("rack", "\x00", "rack controller serving it (a machine moved to another segment)")
			var statics, unstatic multiFlag
			fs.Var(&statics, "static", "IFACE=IP pins an address (repeatable)")
			fs.Var(&unstatic, "unstatic", "IP drops a pinned address (repeatable)")
			_ = fs.Parse(args[2:])
			req := obj{"unstatic": []string(unstatic)}
			if *layout != "\x00" {
				req["layout"] = *layout
			}
			if *rack != "\x00" {
				req["rack_controller"] = *rack
			}
			var st []obj
			for _, s := range statics {
				i, ip, ok := strings.Cut(s, "=")
				if !ok {
					return fmt.Errorf("-static wants IFACE=IP")
				}
				st = append(st, obj{"iface": i, "ip": ip})
			}
			req["static"] = st
			var d obj
			if err := c.do("POST", "/api/v1/machines/"+args[1]+"/network", req, &d); err != nil {
				return err
			}
			printNet(d)
		default:
			usage()
		}
	case "controllers", "controller":
		switch {
		case cmd == "controller" && sub == "rm":
			need(2)
			return c.do("DELETE", "/api/v1/controllers/"+args[1], nil, nil)
		case cmd == "controller" && sub == "join-code":
			fs := newFlags("controller join-code")
			name := fs.String("name", "", "bind the code to this rack controller name")
			ttl := fs.Int("ttl", 60, "minutes the code is good for")
			addr := fs.String("addr", "", "host:port the rack reaches the region's HTTPS at (default: how you reached it)")
			_ = fs.Parse(args[1:])
			var d obj
			if err := c.do("POST", "/api/v1/controllers/join", obj{"name": *name, "ttl_minutes": *ttl, "addr": *addr}, &d); err != nil {
				return err
			}
			fmt.Printf("%s\n\none use, until %s; region %s, CA %s\non the rack host: rollcall rack join <code> -url http://<its address on the segment>\n",
				str(d["code"]), str(d["expires"]), str(d["addr"]), str(d["ca_fingerprint"]))
			return nil
		default:
			var rs []RackController
			if err := c.do("GET", "/api/v1/controllers", nil, &rs); err != nil {
				return err
			}
			fmt.Printf("%-14s %-9s %-7s %-24s %8s %-22s %-20s %s\n", "CONTROLLER", "KIND", "ONLINE", "URL", "MACHINES", "VERSION", "LAST SEEN", "INTERFACES")
			for _, r := range rs {
				var ifs []string
				for _, i := range r.Interfaces {
					ifs = append(ifs, i.Name+"="+strings.Join(i.Addrs, ","))
				}
				fmt.Printf("%-14s %-9s %-7v %-24s %8d %-22s %-20s %s\n", r.Name, r.Kind, r.Online, r.URL, r.Machines, orDash(r.Version), timeStr(r.LastSeen), strings.Join(ifs, " "))
			}
		}
	case "dhcp":
		need(1)
		data, err := c.raw("GET", "/api/v1/controllers/"+args[0]+"/dhcp")
		if err != nil {
			return err
		}
		os.Stdout.Write(data)
	case "ipam":
		return c.ipamCmd(sub, args)
	}
	return nil
}

func (c *client) ipamCmd(sub string, args []string) error {
	printRep := func(rep ipamReport) {
		for _, x := range []struct {
			k string
			v []string
		}{{"created", rep.Created}, {"updated", rep.Updated}, {"deleted", rep.Deleted}, {"conflict", rep.Conflicts}} {
			for _, ip := range x.v {
				fmt.Printf("%-9s %s\n", x.k, ip)
			}
		}
		dry := ""
		if rep.DryRun {
			dry = " (dry run, nothing changed)"
		}
		fmt.Printf("%s: %d created, %d updated, %d deleted, %d conflicts%s\n", orDash(rep.Provider),
			len(rep.Created), len(rep.Updated), len(rep.Deleted), len(rep.Conflicts), dry)
		if rep.Error != "" {
			fmt.Println("error:", rep.Error)
		}
	}
	switch sub {
	case "", "status":
		var st struct {
			Provider string     `json:"provider"`
			URL      string     `json:"url"`
			Zone     string     `json:"dns_zone"`
			Tag      string     `json:"tag"`
			Field    string     `json:"machine_field"`
			Last     ipamReport `json:"last_sync"`
		}
		if err := c.do("GET", "/api/v1/ipam", nil, &st); err != nil {
			return err
		}
		if st.Provider == "" {
			fmt.Println("built-in IPAM only (set ipam.provider in config.json for NetBox)")
			return nil
		}
		fmt.Printf("provider  %s %s\nzone      %s\nowner     tag %q, custom field %q\n", st.Provider, st.URL, orDash(st.Zone), st.Tag, st.Field)
		if st.Last.At.IsZero() {
			fmt.Println("last sync never")
			return nil
		}
		fmt.Printf("last sync %s\n", st.Last.At.Local().Format("2006-01-02 15:04:05"))
		printRep(st.Last)
	case "sync":
		fs := newFlags("ipam sync")
		dry := fs.Bool("dry", false, "show what would change")
		_ = fs.Parse(args[min(1, len(args)):])
		q := ""
		if *dry {
			q = "?dry=1"
		}
		var rep ipamReport
		err := c.do("POST", "/api/v1/ipam/sync"+q, nil, &rep)
		if rep.Provider != "" || rep.Error != "" {
			printRep(rep)
		}
		return err
	case "prefixes", "import":
		var res struct {
			Prefixes []extPrefix `json:"prefixes"`
			Imported []string    `json:"imported"`
		}
		method := "GET"
		if sub == "import" {
			method = "POST"
		}
		if err := c.do(method, "/api/v1/ipam/prefixes", nil, &res); err != nil {
			return err
		}
		fmt.Printf("%-22s %-6s %-5s %-10s %s\n", "PREFIX", "LOCAL", "VLAN", "SITE", "DESCRIPTION")
		for _, p := range res.Prefixes {
			vid := "-"
			if p.VID > 0 {
				vid = strconv.Itoa(p.VID)
			}
			local := "no"
			if p.Local {
				local = "yes"
				if p.Comment != "" {
					local = p.Comment
				}
			}
			fmt.Printf("%-22s %-6s %-5s %-10s %s\n", p.Prefix, local, vid, orDash(p.Site), p.Desc)
		}
		if sub == "prefixes" {
			fmt.Println("prefixes tagged for Rollcall; `rollcall ipam import` creates the missing subnets")
		}
	default:
		usage()
	}
	return nil
}

type multiFlag []string

func (m *multiFlag) String() string     { return strings.Join(*m, ",") }
func (m *multiFlag) Set(v string) error { *m = append(*m, v); return nil }

func lastOctets(ip string) string {
	if strings.Contains(ip, ":") {
		if i := strings.LastIndex(ip, ":"); i >= 0 {
			return ip[i:]
		}
	}
	if i := strings.LastIndex(ip, "."); i >= 0 {
		return ip[i+1:]
	}
	return ip
}

func layoutSummary(l NetLayout) string {
	var p []string
	for _, i := range l.Interfaces {
		var links []string
		for _, lk := range i.Links {
			links = append(links, lk.Subnet+":"+orDash(lk.Mode))
		}
		switch i.Type {
		case "bond":
			p = append(p, fmt.Sprintf("%s(%s)[%s]", orDash(i.Name), strings.Join(i.Members, "+"), strings.Join(links, ",")))
		case "vlan":
			p = append(p, fmt.Sprintf("%s.%d[%s]", i.Parent, i.VID, strings.Join(links, ",")))
		default:
			p = append(p, fmt.Sprintf("%s[%s]", orDash(i.Select), strings.Join(links, ",")))
		}
	}
	return strings.Join(p, " ")
}

func printNet(d obj) {
	fmt.Printf("%s  layout %s  rack controller %s\n", str(d["id"]), str(d["layout"]), str(d["rack_controller"]))
	if d["modeled"] == false {
		fmt.Println("  no subnets are defined: deployed machines use DHCP (rollcall subnet add …)")
	}
	plan, _ := d["plan"].(obj)
	for _, iv := range toList(plan["interfaces"]) {
		i, _ := iv.(obj)
		desc := str(i["type"])
		switch desc {
		case "physical":
			desc = str(i["mac"])
		case "bond":
			var ms []string
			for _, x := range toList(i["members"]) {
				ms = append(ms, str(x))
			}
			desc = "bond " + str(i["bond_mode"]) + " of " + strings.Join(ms, ",")
		case "vlan":
			desc = fmt.Sprintf("vlan %s on %s", str(i["vid"]), str(i["parent"]))
		}
		mtu := ""
		if num(i["mtu"]) > 0 {
			mtu = fmt.Sprintf(" mtu %d", int(num(i["mtu"])))
		}
		fmt.Printf("  %-12s %s%s\n", str(i["name"]), desc, mtu)
		for _, lv := range toList(i["links"]) {
			l, _ := lv.(obj)
			ip := str(l["ip"])
			if ip == "" && str(l["mode"]) == "auto" {
				ip = "(allocated at deploy)"
			} else if ip != "" {
				ip = fmt.Sprintf("%s/%d", ip, int(num(l["prefix"])))
			}
			gw := ""
			if l["default_gateway"] == true {
				gw = " default via " + str(l["gateway"])
			}
			fmt.Printf("      %-8s %-18s %s%s\n", str(l["mode"]), orDash(str(l["subnet"])), ip, gw)
		}
	}
	for _, w := range toList(plan["warnings"]) {
		fmt.Printf("  ! %s\n", str(w))
	}
	b, _ := json.MarshalIndent(d["network_config"], "  ", "  ")
	fmt.Printf("  network-config:\n  %s\n", b)
}