package envoy import ( "errors" "flag" "fmt" "net" "os" "os/exec" "strconv" "strings" "github.com/mitchellh/mapstructure" "github.com/hashicorp/consul/agent/xds" "github.com/hashicorp/consul/api" proxyCmd "github.com/hashicorp/consul/command/connect/proxy" "github.com/hashicorp/consul/command/flags" "github.com/hashicorp/consul/ipaddr" "github.com/hashicorp/go-sockaddr/template" "github.com/mitchellh/cli" ) func New(ui cli.Ui) *cmd { ui = &cli.PrefixedUi{ OutputPrefix: "==> ", InfoPrefix: " ", ErrorPrefix: "==> ", Ui: ui, } c := &cmd{UI: ui} c.init() return c } const DefaultAdminAccessLogPath = "/dev/null" type cmd struct { UI cli.Ui flags *flag.FlagSet http *flags.HTTPFlags help string client *api.Client // flags meshGateway bool proxyID string sidecarFor string adminAccessLogPath string adminBind string envoyBin string bootstrap bool disableCentralConfig bool grpcAddr string // mesh gateway registration information register bool address string wanAddress string deregAfterCritical string bindAddresses map[string]string meshGatewaySvcName string } func (c *cmd) init() { c.flags = flag.NewFlagSet("", flag.ContinueOnError) c.flags.StringVar(&c.proxyID, "proxy-id", "", "The proxy's ID on the local agent.") c.flags.BoolVar(&c.meshGateway, "mesh-gateway", false, "Generate the bootstrap.json but don't exec envoy") c.flags.StringVar(&c.sidecarFor, "sidecar-for", "", "The ID of a service instance on the local agent that this proxy should "+ "become a sidecar for. It requires that the proxy service is registered "+ "with the agent as a connect-proxy with Proxy.DestinationServiceID set "+ "to this value. If more than one such proxy is registered it will fail.") c.flags.StringVar(&c.envoyBin, "envoy-binary", "", "The full path to the envoy binary to run. By default will just search "+ "$PATH. Ignored if -bootstrap is used.") c.flags.StringVar(&c.adminAccessLogPath, "admin-access-log-path", DefaultAdminAccessLogPath, fmt.Sprintf("The path to write the access log for the administration server. If no access "+ "log is desired specify %q. By default it will use %q.", DefaultAdminAccessLogPath, DefaultAdminAccessLogPath)) c.flags.StringVar(&c.adminBind, "admin-bind", "localhost:19000", "The address:port to start envoy's admin server on. Envoy requires this "+ "but care must be taken to ensure it's not exposed to an untrusted network "+ "as it has full control over the secrets and config of the proxy.") c.flags.BoolVar(&c.bootstrap, "bootstrap", false, "Generate the bootstrap.json but don't exec envoy") c.flags.BoolVar(&c.disableCentralConfig, "no-central-config", false, "By default the proxy's bootstrap configuration can be customized "+ "centrally. This requires that the command run on the same agent as the "+ "proxy will and that the agent is reachable when the command is run. In "+ "cases where either assumption is violated this flag will prevent the "+ "command attempting to resolve config from the local agent.") c.flags.StringVar(&c.grpcAddr, "grpc-addr", "", "Set the agent's gRPC address and port (in http(s)://host:port format). "+ "Alternatively, you can specify CONSUL_GRPC_ADDR in ENV.") c.flags.BoolVar(&c.register, "register", false, "Register a new Mesh Gateway service before configuring and starting Envoy") c.flags.StringVar(&c.address, "address", "", "LAN address to advertise in the Mesh Gateway service registration") c.flags.StringVar(&c.wanAddress, "wan-address", "", "WAN address to advertise in the Mesh Gateway service registration") c.flags.Var((*flags.FlagMapValue)(&c.bindAddresses), "bind-address", "Bind "+ "address to use instead of the default binding rules given as `=:` "+ "pairs. This flag may be specified multiple times to add multiple bind addresses.") c.flags.StringVar(&c.meshGatewaySvcName, "service", "mesh-gateway", "Service name to use for the registration") c.flags.StringVar(&c.deregAfterCritical, "deregister-after-critical", "6h", "The amount of time the gateway services health check can be failing before being deregistered") c.http = &flags.HTTPFlags{} flags.Merge(c.flags, c.http.ClientFlags()) c.help = flags.Usage(help, c.flags) } const ( DefaultMeshGatewayPort int = 443 ) func parseAddress(addrStr string) (string, int, error) { if addrStr == "" { // defaulting the port to 443 return "", DefaultMeshGatewayPort, nil } x, err := template.Parse(addrStr) if err != nil { return "", DefaultMeshGatewayPort, fmt.Errorf("Error parsing address %q: %v", addrStr, err) } addr, portStr, err := net.SplitHostPort(x) if err != nil { return "", DefaultMeshGatewayPort, fmt.Errorf("Error parsing address %q: %v", x, err) } port := DefaultMeshGatewayPort if portStr != "" { port, err = strconv.Atoi(portStr) if err != nil { return "", DefaultMeshGatewayPort, fmt.Errorf("Error parsing port %q: %v", portStr, err) } } return addr, port, nil } // canBindInternal is here mainly so we can unit test this with a constant net.Addr list func canBindInternal(addr string, ifAddrs []net.Addr) bool { if addr == "" { return false } ip := net.ParseIP(addr) if ip == nil { return false } ipStr := ip.String() for _, addr := range ifAddrs { switch v := addr.(type) { case *net.IPNet: if v.IP.String() == ipStr { return true } default: if addr.String() == ipStr { return true } } } return false } func canBind(addr string) bool { ifAddrs, err := net.InterfaceAddrs() if err != nil { return false } return canBindInternal(addr, ifAddrs) } func (c *cmd) Run(args []string) int { if err := c.flags.Parse(args); err != nil { return 1 } passThroughArgs := c.flags.Args() // Load the proxy ID and token from env vars if they're set if c.proxyID == "" { c.proxyID = os.Getenv("CONNECT_PROXY_ID") } if c.sidecarFor == "" { c.sidecarFor = os.Getenv("CONNECT_SIDECAR_FOR") } if c.grpcAddr == "" { c.grpcAddr = os.Getenv(api.GRPCAddrEnvName) } // Setup Consul client client, err := c.http.APIClient() if err != nil { c.UI.Error(fmt.Sprintf("Error connecting to Consul agent: %s", err)) return 1 } c.client = client if c.register { if !c.meshGateway { c.UI.Error("Auto-Registration can only be used for mesh gateways") return 1 } lanAddr, lanPort, err := parseAddress(c.address) if err != nil { c.UI.Error(fmt.Sprintf("Failed to parse the -address parameter: %v", err)) return 1 } taggedAddrs := make(map[string]api.ServiceAddress) if lanAddr != "" { taggedAddrs["lan"] = api.ServiceAddress{Address: lanAddr, Port: lanPort} } wanAddr := "" wanPort := lanPort if c.wanAddress != "" { wanAddr, wanPort, err = parseAddress(c.wanAddress) if err != nil { c.UI.Error(fmt.Sprintf("Failed to parse the -wan-address parameter: %v", err)) return 1 } taggedAddrs["wan"] = api.ServiceAddress{Address: wanAddr, Port: wanPort} } tcpCheckAddr := lanAddr if tcpCheckAddr == "" { // fallback to localhost as the gateway has to reside in the same network namespace // as the agent tcpCheckAddr = "127.0.0.1" } var proxyConf *api.AgentServiceConnectProxyConfig if len(c.bindAddresses) > 0 { // override all default binding rules and just bind to the user-supplied addresses bindAddresses := make(map[string]api.ServiceAddress) for addrName, addrStr := range c.bindAddresses { addr, port, err := parseAddress(addrStr) if err != nil { c.UI.Error(fmt.Sprintf("Failed to parse the bind address: %s=%s: %v", addrName, addrStr, err)) return 1 } bindAddresses[addrName] = api.ServiceAddress{Address: addr, Port: port} } proxyConf = &api.AgentServiceConnectProxyConfig{ Config: map[string]interface{}{ "envoy_mesh_gateway_no_default_bind": true, "envoy_mesh_gateway_bind_addresses": bindAddresses, }, } } else if canBind(lanAddr) && canBind(wanAddr) { // when both addresses are bindable then we bind to the tagged addresses // for creating the envoy listeners proxyConf = &api.AgentServiceConnectProxyConfig{ Config: map[string]interface{}{ "envoy_mesh_gateway_no_default_bind": true, "envoy_mesh_gateway_bind_tagged_addresses": true, }, } } else if !canBind(lanAddr) && lanAddr != "" { c.UI.Error(fmt.Sprintf("The LAN address %q will not be bindable. Either set a bindable address or override the bind addresses with -bind-address", lanAddr)) return 1 } svc := api.AgentServiceRegistration{ Kind: api.ServiceKindMeshGateway, Name: c.meshGatewaySvcName, Address: lanAddr, Port: lanPort, TaggedAddresses: taggedAddrs, Proxy: proxyConf, Check: &api.AgentServiceCheck{ Name: "Mesh Gateway Listening", TCP: ipaddr.FormatAddressPort(tcpCheckAddr, lanPort), Interval: "10s", DeregisterCriticalServiceAfter: c.deregAfterCritical, }, } if err := client.Agent().ServiceRegister(&svc); err != nil { c.UI.Error(fmt.Sprintf("Error registering service %q: %s", svc.Name, err)) return 1 } c.UI.Output(fmt.Sprintf("Registered service: %s", svc.Name)) } // See if we need to lookup proxyID if c.proxyID == "" && c.sidecarFor != "" { proxyID, err := c.lookupProxyIDForSidecar() if err != nil { c.UI.Error(err.Error()) return 1 } c.proxyID = proxyID } else if c.proxyID == "" && c.meshGateway { gatewaySvc, err := c.lookupGatewayProxy() if err != nil { c.UI.Error(err.Error()) return 1 } c.proxyID = gatewaySvc.ID c.meshGatewaySvcName = gatewaySvc.Service } if c.proxyID == "" { c.UI.Error("No proxy ID specified. One of -proxy-id or -sidecar-for/-mesh-gateway is " + "required") return 1 } // See if we need to lookup grpcAddr if c.grpcAddr == "" { port, err := c.lookupGRPCPort() if err != nil { c.UI.Error(fmt.Sprintf("Error connecting to Consul agent: %s", err)) } if port <= 0 { // This is the dev mode default and recommended production setting if // enabled. port = 8502 c.UI.Info(fmt.Sprintf("Defaulting to grpc port = %d", port)) } c.grpcAddr = fmt.Sprintf("localhost:%v", port) } // Generate config bootstrapJson, err := c.generateConfig() if err != nil { c.UI.Error(err.Error()) return 1 } if c.bootstrap { // Just output it and we are done os.Stdout.Write(bootstrapJson) return 0 } // Find Envoy binary binary, err := c.findBinary() if err != nil { c.UI.Error("Couldn't find envoy binary: " + err.Error()) return 1 } err = execEnvoy(binary, nil, passThroughArgs, bootstrapJson) if err == errUnsupportedOS { c.UI.Error("Directly running Envoy is only supported on linux and macOS " + "since envoy itself doesn't build on other platforms currently.") c.UI.Error("Use the -bootstrap option to generate the JSON to use when running envoy " + "on a supported OS or via a container or VM.") return 1 } else if err != nil { c.UI.Error(err.Error()) return 1 } return 0 } var errUnsupportedOS = errors.New("envoy: not implemented on this operating system") func (c *cmd) findBinary() (string, error) { if c.envoyBin != "" { return c.envoyBin, nil } return exec.LookPath("envoy") } func (c *cmd) templateArgs() (*BootstrapTplArgs, error) { httpCfg := api.DefaultConfig() c.http.MergeOntoConfig(httpCfg) // Trigger the Client init to do any last-minute updates to the Config. if _, err := api.NewClient(httpCfg); err != nil { return nil, err } // Decide on TLS if the scheme is provided and indicates it, if the HTTP env // suggests TLS is supported explicitly (CONSUL_HTTP_SSL) or implicitly // (CONSUL_HTTP_ADDR) is https:// useTLS := false if strings.HasPrefix(strings.ToLower(c.grpcAddr), "https://") { useTLS = true } else if useSSLEnv := os.Getenv(api.HTTPSSLEnvName); useSSLEnv != "" { if enabled, err := strconv.ParseBool(useSSLEnv); err != nil { useTLS = enabled } } else if strings.HasPrefix(strings.ToLower(httpCfg.Address), "https://") { useTLS = true } // We want to allow grpcAddr set as host:port with no scheme but if the host // is an IP this will fail to parse as a URL with "parse 127.0.0.1:8500: first // path segment in URL cannot contain colon". On the other hand we also // support both http(s)://host:port and unix:///path/to/file. var agentAddr, agentPort, agentSock string if grpcAddr := strings.TrimPrefix(c.grpcAddr, "unix://"); grpcAddr != c.grpcAddr { // Path to unix socket agentSock = grpcAddr } else { // Parse as host:port with option http prefix grpcAddr = strings.TrimPrefix(c.grpcAddr, "http://") grpcAddr = strings.TrimPrefix(c.grpcAddr, "https://") var err error agentAddr, agentPort, err = net.SplitHostPort(grpcAddr) if err != nil { return nil, fmt.Errorf("Invalid Consul HTTP address: %s", err) } if agentAddr == "" { agentAddr = "127.0.0.1" } // We use STATIC for agent which means we need to resolve DNS names like // `localhost` ourselves. We could use STRICT_DNS or LOGICAL_DNS with envoy // but Envoy resolves `localhost` differently to go on macOS at least which // causes paper cuts like default dev agent (which binds specifically to // 127.0.0.1) isn't reachable since Envoy resolves localhost to `[::]` and // can't connect. agentIP, err := net.ResolveIPAddr("ip", agentAddr) if err != nil { return nil, fmt.Errorf("Failed to resolve agent address: %s", err) } agentAddr = agentIP.String() } adminAddr, adminPort, err := net.SplitHostPort(c.adminBind) if err != nil { return nil, fmt.Errorf("Invalid Consul HTTP address: %s", err) } // Envoy requires IP addresses to bind too when using static so resolve DNS or // localhost here. adminBindIP, err := net.ResolveIPAddr("ip", adminAddr) if err != nil { return nil, fmt.Errorf("Failed to resolve admin bind address: %s", err) } // Ideally the cluster should be the service name. We may or may not have that // yet depending on the arguments used so make a best effort here. In the // common case, even if the command was invoked with proxy-id and we don't // know service name yet, we will after we resolve the proxy's config in a bit // and will update this then. cluster := c.proxyID if c.sidecarFor != "" { cluster = c.sidecarFor } else if c.meshGateway && c.meshGatewaySvcName != "" { cluster = c.meshGatewaySvcName } adminAccessLogPath := c.adminAccessLogPath if adminAccessLogPath == "" { adminAccessLogPath = DefaultAdminAccessLogPath } return &BootstrapTplArgs{ ProxyCluster: cluster, ProxyID: c.proxyID, AgentAddress: agentAddr, AgentPort: agentPort, AgentSocket: agentSock, AgentTLS: useTLS, AgentCAFile: httpCfg.TLSConfig.CAFile, AdminAccessLogPath: adminAccessLogPath, AdminBindAddress: adminBindIP.String(), AdminBindPort: adminPort, Token: httpCfg.Token, LocalAgentClusterName: xds.LocalAgentClusterName, }, nil } func (c *cmd) generateConfig() ([]byte, error) { args, err := c.templateArgs() if err != nil { return nil, err } var bsCfg BootstrapConfig if !c.disableCentralConfig { // Fetch any customization from the registration svc, _, err := c.client.Agent().Service(c.proxyID, nil) if err != nil { return nil, fmt.Errorf("failed fetch proxy config from local agent: %s", err) } if svc.Proxy == nil { return nil, errors.New("service is not a Connect proxy or mesh gateway") } // Parse the bootstrap config if err := mapstructure.WeakDecode(svc.Proxy.Config, &bsCfg); err != nil { return nil, fmt.Errorf("failed parsing Proxy.Config: %s", err) } if svc.Proxy.DestinationServiceName != "" { // Override cluster now we know the actual service name args.ProxyCluster = svc.Proxy.DestinationServiceName } } return bsCfg.GenerateJSON(args) } func (c *cmd) lookupProxyIDForSidecar() (string, error) { return proxyCmd.LookupProxyIDForSidecar(c.client, c.sidecarFor) } func (c *cmd) lookupGatewayProxy() (*api.AgentService, error) { return proxyCmd.LookupGatewayProxy(c.client) } func (c *cmd) lookupGRPCPort() (int, error) { self, err := c.client.Agent().Self() if err != nil { return 0, err } cfg, ok := self["DebugConfig"] if !ok { return 0, fmt.Errorf("unexpected agent response: no debug config") } port, ok := cfg["GRPCPort"] if !ok { return 0, fmt.Errorf("agent does not have grpc port enabled") } portN, ok := port.(float64) if !ok { return 0, fmt.Errorf("invalid grpc port in agent response") } return int(portN), nil } func (c *cmd) Synopsis() string { return synopsis } func (c *cmd) Help() string { return c.help } const synopsis = "Runs or Configures Envoy as a Connect proxy" const help = ` Usage: consul connect envoy [options] Generates the bootstrap configuration needed to start an Envoy proxy instance for use as a Connect sidecar for a particular service instance. By default it will generate the config and then exec Envoy directly until it exits normally. It will search $PATH for the envoy binary but this can be overridden with -envoy-binary. It can instead only generate the bootstrap.json based on the current ENV and arguments using -bootstrap. The proxy requires service:write permissions for the service it represents. The token may be passed via the CLI or the CONSUL_TOKEN environment variable. The example below shows how to start a local proxy as a sidecar to a "web" service instance. It assumes that the proxy was already registered with it's Config for example via a sidecar_service block. $ consul connect envoy -sidecar-for web `