remove DB dependency of tailNode conversion, add test

Signed-off-by: Kristoffer Dalby <kristoffer@tailscale.com>

hscontrol/mapper/tail.go

@@ -0,0 +1,151 @@
+package mapper
+
+import (
+	"fmt"
+	"net/netip"
+	"strconv"
+	"time"
+
+	"github.com/juanfont/headscale/hscontrol/policy"
+	"github.com/juanfont/headscale/hscontrol/types"
+	"github.com/juanfont/headscale/hscontrol/util"
+	"github.com/samber/lo"
+	"tailscale.com/tailcfg"
+)
+
+func tailNodes(
+	machines types.Machines,
+	pol *policy.ACLPolicy,
+	dnsConfig *tailcfg.DNSConfig,
+	baseDomain string,
+	stripEmailDomain bool,
+) ([]*tailcfg.Node, error) {
+	nodes := make([]*tailcfg.Node, len(machines))
+
+	for index, machine := range machines {
+		node, err := tailNode(
+			machine,
+			pol,
+			dnsConfig,
+			baseDomain,
+			stripEmailDomain,
+		)
+		if err != nil {
+			return nil, err
+		}
+
+		nodes[index] = node
+	}
+
+	return nodes, nil
+}
+
+// tailNode converts a Machine into a Tailscale Node. includeRoutes is false for shared nodes
+// as per the expected behaviour in the official SaaS.
+func tailNode(
+	machine types.Machine,
+	pol *policy.ACLPolicy,
+	dnsConfig *tailcfg.DNSConfig,
+	baseDomain string,
+	stripEmailDomain bool,
+) (*tailcfg.Node, error) {
+	nodeKey, err := machine.NodePublicKey()
+	if err != nil {
+		return nil, err
+	}
+
+	// MachineKey is only used in the legacy protocol
+	machineKey, err := machine.MachinePublicKey()
+	if err != nil {
+		return nil, err
+	}
+
+	discoKey, err := machine.DiscoPublicKey()
+	if err != nil {
+		return nil, err
+	}
+
+	addrs := machine.IPAddresses.Prefixes()
+
+	allowedIPs := append(
+		[]netip.Prefix{},
+		addrs...) // we append the node own IP, as it is required by the clients
+
+	primaryPrefixes := []netip.Prefix{}
+
+	for _, route := range machine.Routes {
+		if route.Enabled {
+			if route.IsPrimary {
+				allowedIPs = append(allowedIPs, netip.Prefix(route.Prefix))
+				primaryPrefixes = append(primaryPrefixes, netip.Prefix(route.Prefix))
+			} else if route.IsExitRoute() {
+				allowedIPs = append(allowedIPs, netip.Prefix(route.Prefix))
+			}
+		}
+	}
+
+	var derp string
+	if machine.HostInfo.NetInfo != nil {
+		derp = fmt.Sprintf("127.3.3.40:%d", machine.HostInfo.NetInfo.PreferredDERP)
+	} else {
+		derp = "127.3.3.40:0" // Zero means disconnected or unknown.
+	}
+
+	var keyExpiry time.Time
+	if machine.Expiry != nil {
+		keyExpiry = *machine.Expiry
+	} else {
+		keyExpiry = time.Time{}
+	}
+
+	hostname, err := machine.GetFQDN(dnsConfig, baseDomain)
+	if err != nil {
+		return nil, err
+	}
+
+	hostInfo := machine.GetHostInfo()
+
+	online := machine.IsOnline()
+
+	tags, _ := pol.GetTagsOfMachine(machine, stripEmailDomain)
+	tags = lo.Uniq(append(tags, machine.ForcedTags...))
+
+	node := tailcfg.Node{
+		ID: tailcfg.NodeID(machine.ID), // this is the actual ID
+		StableID: tailcfg.StableNodeID(
+			strconv.FormatUint(machine.ID, util.Base10),
+		), // in headscale, unlike tailcontrol server, IDs are permanent
+		Name: hostname,
+
+		User: tailcfg.UserID(machine.UserID),
+
+		Key:       nodeKey,
+		KeyExpiry: keyExpiry,
+
+		Machine:    machineKey,
+		DiscoKey:   discoKey,
+		Addresses:  addrs,
+		AllowedIPs: allowedIPs,
+		Endpoints:  machine.Endpoints,
+		DERP:       derp,
+		Hostinfo:   hostInfo.View(),
+		Created:    machine.CreatedAt,
+
+		Tags: tags,
+
+		PrimaryRoutes: primaryPrefixes,
+
+		LastSeen:          machine.LastSeen,
+		Online:            &online,
+		KeepAlive:         true,
+		MachineAuthorized: !machine.IsExpired(),
+
+		Capabilities: []string{
+			tailcfg.CapabilityFileSharing,
+			tailcfg.CapabilityAdmin,
+			tailcfg.CapabilitySSH,
+		},
+	}
+
+	return &node, nil
+}