cloudflare/cloudflared
Publicmirrored from https://github.com/cloudflare/cloudflaredAvailable
connection/manager.go
299lines · modecode
| 1 | package connection |
| 2 | |
| 3 | import ( |
| 4 | "context" |
| 5 | "crypto/tls" |
| 6 | "fmt" |
| 7 | "sync" |
| 8 | "time" |
| 9 | |
| 10 | "github.com/google/uuid" |
| 11 | "github.com/pkg/errors" |
| 12 | "github.com/prometheus/client_golang/prometheus" |
| 13 | "github.com/sirupsen/logrus" |
| 14 | |
| 15 | "github.com/cloudflare/cloudflared/cmd/cloudflared/buildinfo" |
| 16 | "github.com/cloudflare/cloudflared/h2mux" |
| 17 | "github.com/cloudflare/cloudflared/streamhandler" |
| 18 | tunnelpogs "github.com/cloudflare/cloudflared/tunnelrpc/pogs" |
| 19 | ) |
| 20 | |
| 21 | const ( |
| 22 | quickStartLink = "https://developers.cloudflare.com/argo-tunnel/quickstart/" |
| 23 | faqLink = "https://developers.cloudflare.com/argo-tunnel/faq/" |
| 24 | defaultRetryAfter = time.Second * 5 |
| 25 | packageNamespace = "connection" |
| 26 | edgeManagerSubsystem = "edgemanager" |
| 27 | ) |
| 28 | |
| 29 | // EdgeManager manages connections with the edge |
| 30 | type EdgeManager struct { |
| 31 | // streamHandler handles stream opened by the edge |
| 32 | streamHandler *streamhandler.StreamHandler |
| 33 | // TLSConfig is the TLS configuration to connect with edge |
| 34 | tlsConfig *tls.Config |
| 35 | // cloudflaredConfig is the cloudflared configuration that is determined when the process first starts |
| 36 | cloudflaredConfig *CloudflaredConfig |
| 37 | // serviceDiscoverer returns the next edge addr to connect to |
| 38 | serviceDiscoverer EdgeServiceDiscoverer |
| 39 | // state is attributes of ConnectionManager that can change during runtime. |
| 40 | state *edgeManagerState |
| 41 | |
| 42 | logger *logrus.Entry |
| 43 | |
| 44 | metrics *metrics |
| 45 | } |
| 46 | |
| 47 | type metrics struct { |
| 48 | // activeStreams is a gauge shared by all muxers of this process to expose the total number of active streams |
| 49 | activeStreams prometheus.Gauge |
| 50 | } |
| 51 | |
| 52 | func newMetrics(namespace, subsystem string) *metrics { |
| 53 | return &metrics{ |
| 54 | activeStreams: h2mux.NewActiveStreamsMetrics(namespace, subsystem), |
| 55 | } |
| 56 | } |
| 57 | |
| 58 | // EdgeManagerConfigurable is the configurable attributes of a EdgeConnectionManager |
| 59 | type EdgeManagerConfigurable struct { |
| 60 | TunnelHostnames []h2mux.TunnelHostname |
| 61 | *tunnelpogs.EdgeConnectionConfig |
| 62 | } |
| 63 | |
| 64 | type CloudflaredConfig struct { |
| 65 | CloudflaredID uuid.UUID |
| 66 | Tags []tunnelpogs.Tag |
| 67 | BuildInfo *buildinfo.BuildInfo |
| 68 | IntentLabel string |
| 69 | } |
| 70 | |
| 71 | func NewEdgeManager( |
| 72 | streamHandler *streamhandler.StreamHandler, |
| 73 | edgeConnMgrConfigurable *EdgeManagerConfigurable, |
| 74 | userCredential []byte, |
| 75 | tlsConfig *tls.Config, |
| 76 | serviceDiscoverer EdgeServiceDiscoverer, |
| 77 | cloudflaredConfig *CloudflaredConfig, |
| 78 | logger *logrus.Logger, |
| 79 | ) *EdgeManager { |
| 80 | return &EdgeManager{ |
| 81 | streamHandler: streamHandler, |
| 82 | tlsConfig: tlsConfig, |
| 83 | cloudflaredConfig: cloudflaredConfig, |
| 84 | serviceDiscoverer: serviceDiscoverer, |
| 85 | state: newEdgeConnectionManagerState(edgeConnMgrConfigurable, userCredential), |
| 86 | logger: logger.WithField("subsystem", "connectionManager"), |
| 87 | metrics: newMetrics(packageNamespace, edgeManagerSubsystem), |
| 88 | } |
| 89 | } |
| 90 | |
| 91 | func (em *EdgeManager) Run(ctx context.Context) error { |
| 92 | defer em.shutdown() |
| 93 | |
| 94 | resolveEdgeIPTicker := time.Tick(resolveEdgeAddrTTL) |
| 95 | for { |
| 96 | select { |
| 97 | case <-ctx.Done(): |
| 98 | return errors.Wrap(ctx.Err(), "EdgeConnectionManager terminated") |
| 99 | case <-resolveEdgeIPTicker: |
| 100 | if err := em.serviceDiscoverer.Refresh(); err != nil { |
| 101 | em.logger.WithError(err).Warn("Cannot refresh Cloudflare edge addresses") |
| 102 | } |
| 103 | default: |
| 104 | time.Sleep(1 * time.Second) |
| 105 | } |
| 106 | // Create/delete connection one at a time, so we don't need to adjust for connections that are being created/deleted |
| 107 | // in shouldCreateConnection or shouldReduceConnection calculation |
| 108 | if em.state.shouldCreateConnection(em.serviceDiscoverer.AvailableAddrs()) { |
| 109 | if connErr := em.newConnection(ctx); connErr != nil { |
| 110 | if !connErr.ShouldRetry { |
| 111 | em.logger.WithError(connErr).Error(em.noRetryMessage()) |
| 112 | return connErr |
| 113 | } |
| 114 | em.logger.WithError(connErr).Error("cannot create new connection") |
| 115 | } |
| 116 | } else if em.state.shouldReduceConnection() { |
| 117 | if err := em.closeConnection(ctx); err != nil { |
| 118 | em.logger.WithError(err).Error("cannot close connection") |
| 119 | } |
| 120 | } |
| 121 | } |
| 122 | } |
| 123 | |
| 124 | func (em *EdgeManager) UpdateConfigurable(newConfigurable *EdgeManagerConfigurable) { |
| 125 | em.logger.Infof("New edge connection manager configuration %+v", newConfigurable) |
| 126 | em.state.updateConfigurable(newConfigurable) |
| 127 | } |
| 128 | |
| 129 | func (em *EdgeManager) newConnection(ctx context.Context) *tunnelpogs.ConnectError { |
| 130 | edgeTCPAddr, err := em.serviceDiscoverer.Addr() |
| 131 | if err != nil { |
| 132 | return retryConnection(fmt.Sprintf("edge address discovery error: %v", err)) |
| 133 | } |
| 134 | configurable := em.state.getConfigurable() |
| 135 | edgeConn, err := DialEdge(ctx, configurable.Timeout, em.tlsConfig, edgeTCPAddr) |
| 136 | if err != nil { |
| 137 | return retryConnection(fmt.Sprintf("dial edge error: %v", err)) |
| 138 | } |
| 139 | // Establish a muxed connection with the edge |
| 140 | // Client mux handshake with agent server |
| 141 | muxer, err := h2mux.Handshake(edgeConn, edgeConn, h2mux.MuxerConfig{ |
| 142 | Timeout: configurable.Timeout, |
| 143 | Handler: em.streamHandler, |
| 144 | IsClient: true, |
| 145 | HeartbeatInterval: configurable.HeartbeatInterval, |
| 146 | MaxHeartbeats: configurable.MaxFailedHeartbeats, |
| 147 | Logger: em.logger.WithField("subsystem", "muxer"), |
| 148 | }, em.metrics.activeStreams) |
| 149 | if err != nil { |
| 150 | retryConnection(fmt.Sprintf("couldn't perform handshake with edge: %v", err)) |
| 151 | } |
| 152 | |
| 153 | h2muxConn, err := newConnection(muxer, edgeTCPAddr) |
| 154 | if err != nil { |
| 155 | return retryConnection(fmt.Sprintf("couldn't create h2mux connection: %v", err)) |
| 156 | } |
| 157 | |
| 158 | go em.serveConn(ctx, h2muxConn) |
| 159 | |
| 160 | connResult, err := h2muxConn.Connect(ctx, &tunnelpogs.ConnectParameters{ |
| 161 | CloudflaredID: em.cloudflaredConfig.CloudflaredID, |
| 162 | CloudflaredVersion: em.cloudflaredConfig.BuildInfo.CloudflaredVersion, |
| 163 | NumPreviousAttempts: 0, |
| 164 | OriginCert: em.state.getUserCredential(), |
| 165 | IntentLabel: em.cloudflaredConfig.IntentLabel, |
| 166 | Tags: em.cloudflaredConfig.Tags, |
| 167 | }, em.logger) |
| 168 | if err != nil { |
| 169 | h2muxConn.Shutdown() |
| 170 | return retryConnection(fmt.Sprintf("couldn't connect to edge: %v", err)) |
| 171 | } |
| 172 | |
| 173 | if connErr := connResult.ConnectError(); connErr != nil { |
| 174 | return connErr |
| 175 | } |
| 176 | |
| 177 | em.state.newConnection(h2muxConn) |
| 178 | em.logger.Infof("connected to %s", connResult.ConnectedTo()) |
| 179 | |
| 180 | if connResult.ClientConfig() != nil { |
| 181 | em.streamHandler.UseConfiguration(ctx, connResult.ClientConfig()) |
| 182 | } |
| 183 | return nil |
| 184 | } |
| 185 | |
| 186 | func (em *EdgeManager) closeConnection(ctx context.Context) error { |
| 187 | conn := em.state.getFirstConnection() |
| 188 | if conn == nil { |
| 189 | return fmt.Errorf("no connection to close") |
| 190 | } |
| 191 | conn.Shutdown() |
| 192 | // teardown will be handled by EdgeManager.serveConn in another goroutine |
| 193 | return nil |
| 194 | } |
| 195 | |
| 196 | func (em *EdgeManager) serveConn(ctx context.Context, conn *Connection) { |
| 197 | err := conn.Serve(ctx) |
| 198 | em.logger.WithError(err).Warn("Connection closed") |
| 199 | em.state.closeConnection(conn) |
| 200 | em.serviceDiscoverer.ReplaceAddr(conn.addr) |
| 201 | } |
| 202 | |
| 203 | func (em *EdgeManager) noRetryMessage() string { |
| 204 | messageTemplate := "cloudflared could not register an Argo Tunnel on your account. Please confirm the following before trying again:" + |
| 205 | "1. You have Argo Smart Routing enabled in your account, See Enable Argo section of %s." + |
| 206 | "2. Your credential at %s is still valid. See %s." |
| 207 | return fmt.Sprintf(messageTemplate, quickStartLink, em.state.getConfigurable().UserCredentialPath, faqLink) |
| 208 | } |
| 209 | |
| 210 | func (em *EdgeManager) shutdown() { |
| 211 | em.state.shutdown() |
| 212 | } |
| 213 | |
| 214 | type edgeManagerState struct { |
| 215 | sync.RWMutex |
| 216 | configurable *EdgeManagerConfigurable |
| 217 | userCredential []byte |
| 218 | conns map[uuid.UUID]*Connection |
| 219 | } |
| 220 | |
| 221 | func newEdgeConnectionManagerState(configurable *EdgeManagerConfigurable, userCredential []byte) *edgeManagerState { |
| 222 | return &edgeManagerState{ |
| 223 | configurable: configurable, |
| 224 | userCredential: userCredential, |
| 225 | conns: make(map[uuid.UUID]*Connection), |
| 226 | } |
| 227 | } |
| 228 | |
| 229 | func (ems *edgeManagerState) shouldCreateConnection(availableEdgeAddrs int) bool { |
| 230 | ems.RLock() |
| 231 | defer ems.RUnlock() |
| 232 | expectedHAConns := int(ems.configurable.NumHAConnections) |
| 233 | if availableEdgeAddrs < expectedHAConns { |
| 234 | expectedHAConns = availableEdgeAddrs |
| 235 | } |
| 236 | return len(ems.conns) < expectedHAConns |
| 237 | } |
| 238 | |
| 239 | func (ems *edgeManagerState) shouldReduceConnection() bool { |
| 240 | ems.RLock() |
| 241 | defer ems.RUnlock() |
| 242 | return uint8(len(ems.conns)) > ems.configurable.NumHAConnections |
| 243 | } |
| 244 | |
| 245 | func (ems *edgeManagerState) newConnection(conn *Connection) { |
| 246 | ems.Lock() |
| 247 | defer ems.Unlock() |
| 248 | ems.conns[conn.id] = conn |
| 249 | } |
| 250 | |
| 251 | func (ems *edgeManagerState) closeConnection(conn *Connection) { |
| 252 | ems.Lock() |
| 253 | defer ems.Unlock() |
| 254 | delete(ems.conns, conn.id) |
| 255 | } |
| 256 | |
| 257 | func (ems *edgeManagerState) getFirstConnection() *Connection { |
| 258 | ems.RLock() |
| 259 | defer ems.RUnlock() |
| 260 | |
| 261 | for _, conn := range ems.conns { |
| 262 | return conn |
| 263 | } |
| 264 | return nil |
| 265 | } |
| 266 | |
| 267 | func (ems *edgeManagerState) shutdown() { |
| 268 | ems.Lock() |
| 269 | defer ems.Unlock() |
| 270 | for _, conn := range ems.conns { |
| 271 | conn.Shutdown() |
| 272 | } |
| 273 | } |
| 274 | |
| 275 | func (ems *edgeManagerState) getConfigurable() *EdgeManagerConfigurable { |
| 276 | ems.Lock() |
| 277 | defer ems.Unlock() |
| 278 | return ems.configurable |
| 279 | } |
| 280 | |
| 281 | func (ems *edgeManagerState) updateConfigurable(newConfigurable *EdgeManagerConfigurable) { |
| 282 | ems.Lock() |
| 283 | defer ems.Unlock() |
| 284 | ems.configurable = newConfigurable |
| 285 | } |
| 286 | |
| 287 | func (ems *edgeManagerState) getUserCredential() []byte { |
| 288 | ems.RLock() |
| 289 | defer ems.RUnlock() |
| 290 | return ems.userCredential |
| 291 | } |
| 292 | |
| 293 | func retryConnection(cause string) *tunnelpogs.ConnectError { |
| 294 | return &tunnelpogs.ConnectError{ |
| 295 | Cause: cause, |
| 296 | RetryAfter: defaultRetryAfter, |
| 297 | ShouldRetry: true, |
| 298 | } |
| 299 | } |
| 300 | |