// Copyright (c) 2020 Tailscale Inc & AUTHORS All rights reserved. // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. // Package netmap contains the netmap.NetworkMap type. package netmap import ( "encoding/json" "fmt" "reflect" "strings" "time" "inet.af/netaddr" "tailscale.com/tailcfg" "tailscale.com/types/wgkey" "tailscale.com/wgengine/filter" ) // NetworkMap is the current state of the world. // // The fields should all be considered read-only. They might // alias parts of previous NetworkMap values. type NetworkMap struct { // Core networking SelfNode *tailcfg.Node NodeKey tailcfg.NodeKey PrivateKey wgkey.Private Expiry time.Time // Name is the DNS name assigned to this node. Name string Addresses []netaddr.IPPrefix // same as tailcfg.Node.Addresses (IP addresses of this Node directly) LocalPort uint16 // used for debugging MachineStatus tailcfg.MachineStatus MachineKey tailcfg.MachineKey Peers []*tailcfg.Node // sorted by Node.ID DNS tailcfg.DNSConfig Hostinfo tailcfg.Hostinfo PacketFilter []filter.Match // CollectServices reports whether this node's Tailnet has // requested that info about services be included in HostInfo. // If set, Hostinfo.ShieldsUp blocks services collection; that // takes precedence over this field. CollectServices bool // DERPMap is the last DERP server map received. It's reused // between updates and should not be modified. DERPMap *tailcfg.DERPMap // Debug knobs from control server for debug or feature gating. Debug *tailcfg.Debug // ACLs User tailcfg.UserID Domain string UserProfiles map[tailcfg.UserID]tailcfg.UserProfile } // MagicDNSSuffix returns the domain's MagicDNS suffix (even if // MagicDNS isn't necessarily in use). // // It will neither start nor end with a period. func (nm *NetworkMap) MagicDNSSuffix() string { name := strings.Trim(nm.Name, ".") if i := strings.Index(name, "."); i != -1 { name = name[i+1:] } return name } func (nm *NetworkMap) String() string { return nm.Concise() } func (nm *NetworkMap) Concise() string { buf := new(strings.Builder) nm.printConciseHeader(buf) for _, p := range nm.Peers { printPeerConcise(buf, p) } return buf.String() } // printConciseHeader prints a concise header line representing nm to buf. // // If this function is changed to access different fields of nm, keep // in equalConciseHeader in sync. func (nm *NetworkMap) printConciseHeader(buf *strings.Builder) { fmt.Fprintf(buf, "netmap: self: %v auth=%v", nm.NodeKey.ShortString(), nm.MachineStatus) login := nm.UserProfiles[nm.User].LoginName if login == "" { if nm.User.IsZero() { login = "?" } else { login = fmt.Sprint(nm.User) } } fmt.Fprintf(buf, " u=%s", login) if nm.LocalPort != 0 { fmt.Fprintf(buf, " port=%v", nm.LocalPort) } if nm.Debug != nil { j, _ := json.Marshal(nm.Debug) fmt.Fprintf(buf, " debug=%s", j) } fmt.Fprintf(buf, " %v", nm.Addresses) buf.WriteByte('\n') } // equalConciseHeader reports whether a and b are equal for the fields // used by printConciseHeader. func (a *NetworkMap) equalConciseHeader(b *NetworkMap) bool { if a.NodeKey != b.NodeKey || a.MachineStatus != b.MachineStatus || a.LocalPort != b.LocalPort || a.User != b.User || len(a.Addresses) != len(b.Addresses) { return false } for i, a := range a.Addresses { if b.Addresses[i] != a { return false } } return (a.Debug == nil && b.Debug == nil) || reflect.DeepEqual(a.Debug, b.Debug) } // printPeerConcise appends to buf a line repsenting the peer p. // // If this function is changed to access different fields of p, keep // in nodeConciseEqual in sync. func printPeerConcise(buf *strings.Builder, p *tailcfg.Node) { aip := make([]string, len(p.AllowedIPs)) for i, a := range p.AllowedIPs { s := strings.TrimSuffix(fmt.Sprint(a), "/32") aip[i] = s } ep := make([]string, len(p.Endpoints)) for i, e := range p.Endpoints { // Align vertically on the ':' between IP and port colon := strings.IndexByte(e, ':') spaces := 0 for colon > 0 && len(e)+spaces-colon < 6 { spaces++ colon-- } ep[i] = fmt.Sprintf("%21v", e+strings.Repeat(" ", spaces)) } derp := p.DERP const derpPrefix = "127.3.3.40:" if strings.HasPrefix(derp, derpPrefix) { derp = "D" + derp[len(derpPrefix):] } var discoShort string if !p.DiscoKey.IsZero() { discoShort = p.DiscoKey.ShortString() + " " } // Most of the time, aip is just one element, so format the // table to look good in that case. This will also make multi- // subnet nodes stand out visually. fmt.Fprintf(buf, " %v %s%-2v %-15v : %v\n", p.Key.ShortString(), discoShort, derp, strings.Join(aip, " "), strings.Join(ep, " ")) } // nodeConciseEqual reports whether a and b are equal for the fields accessed by printPeerConcise. func nodeConciseEqual(a, b *tailcfg.Node) bool { return a.Key == b.Key && a.DERP == b.DERP && a.DiscoKey == b.DiscoKey && eqCIDRsIgnoreNil(a.AllowedIPs, b.AllowedIPs) && eqStringsIgnoreNil(a.Endpoints, b.Endpoints) } func (b *NetworkMap) ConciseDiffFrom(a *NetworkMap) string { var diff strings.Builder // See if header (non-peers, "bare") part of the network map changed. // If so, print its diff lines first. if !a.equalConciseHeader(b) { diff.WriteByte('-') a.printConciseHeader(&diff) diff.WriteByte('+') b.printConciseHeader(&diff) } aps, bps := a.Peers, b.Peers for len(aps) > 0 && len(bps) > 0 { pa, pb := aps[0], bps[0] switch { case pa.ID == pb.ID: if !nodeConciseEqual(pa, pb) { diff.WriteByte('-') printPeerConcise(&diff, pa) diff.WriteByte('+') printPeerConcise(&diff, pb) } aps, bps = aps[1:], bps[1:] case pa.ID > pb.ID: // New peer in b. diff.WriteByte('+') printPeerConcise(&diff, pb) bps = bps[1:] case pb.ID > pa.ID: // Deleted peer in b. diff.WriteByte('-') printPeerConcise(&diff, pa) aps = aps[1:] } } for _, pa := range aps { diff.WriteByte('-') printPeerConcise(&diff, pa) } for _, pb := range bps { diff.WriteByte('+') printPeerConcise(&diff, pb) } return diff.String() } func (nm *NetworkMap) JSON() string { b, err := json.MarshalIndent(*nm, "", " ") if err != nil { return fmt.Sprintf("[json error: %v]", err) } return string(b) } // WGConfigFlags is a bitmask of flags to control the behavior of the // wireguard configuration generation done by NetMap.WGCfg. type WGConfigFlags int const ( AllowSingleHosts WGConfigFlags = 1 << iota AllowSubnetRoutes ) // eqStringsIgnoreNil reports whether a and b have the same length and // contents, but ignore whether a or b are nil. func eqStringsIgnoreNil(a, b []string) bool { if len(a) != len(b) { return false } for i, v := range a { if v != b[i] { return false } } return true } // eqCIDRsIgnoreNil reports whether a and b have the same length and // contents, but ignore whether a or b are nil. func eqCIDRsIgnoreNil(a, b []netaddr.IPPrefix) bool { if len(a) != len(b) { return false } for i, v := range a { if v != b[i] { return false } } return true }