package envoy import ( "errors" "flag" "fmt" "net" "os" "os/exec" "strings" "github.com/mitchellh/cli" "github.com/mitchellh/mapstructure" "github.com/hashicorp/consul/agent/structs" "github.com/hashicorp/consul/agent/xds" "github.com/hashicorp/consul/agent/xds/proxysupport" "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/consul/tlsutil" ) func New(ui cli.Ui) *cmd { 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 gateway string proxyID string sidecarFor string adminAccessLogPath string adminBind string envoyBin string bootstrap bool disableCentralConfig bool grpcAddr string envoyVersion string prometheusBackendPort string prometheusScrapePath string // mesh gateway registration information register bool lanAddress ServiceAddressValue wanAddress ServiceAddressValue deregAfterCritical string bindAddresses ServiceAddressMapValue exposeServers bool omitDeprecatedTags bool gatewaySvcName string gatewayKind api.ServiceKind } const meshGatewayVal = "mesh" var defaultEnvoyVersion = proxysupport.EnvoyVersions[0] var supportedGateways = map[string]api.ServiceKind{ "mesh": api.ServiceKindMeshGateway, "terminating": api.ServiceKindTerminatingGateway, "ingress": api.ServiceKindIngressGateway, } func (c *cmd) init() { c.flags = flag.NewFlagSet("", flag.ContinueOnError) c.flags.StringVar(&c.proxyID, "proxy-id", os.Getenv("CONNECT_PROXY_ID"), "The proxy's ID on the local agent.") // Deprecated in favor of `gateway` c.flags.BoolVar(&c.meshGateway, "mesh-gateway", false, "Configure Envoy as a Mesh Gateway.") c.flags.StringVar(&c.gateway, "gateway", "", "The type of gateway to register. One of: terminating, ingress, or mesh") c.flags.StringVar(&c.sidecarFor, "sidecar-for", os.Getenv("CONNECT_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", os.Getenv(api.GRPCAddrEnvName), "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.StringVar(&c.envoyVersion, "envoy-version", defaultEnvoyVersion, "Sets the envoy-version that the envoy binary has.") c.flags.BoolVar(&c.register, "register", false, "Register a new gateway service before configuring and starting Envoy") c.flags.Var(&c.lanAddress, "address", "LAN address to advertise in the gateway service registration") c.flags.Var(&c.wanAddress, "wan-address", "WAN address to advertise in the gateway service registration. For ingress gateways, "+ "only an IP address (without a port) is required.") c.flags.Var(&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.gatewaySvcName, "service", "", "Service name to use for the registration") c.flags.BoolVar(&c.exposeServers, "expose-servers", false, "Expose the servers for WAN federation via this mesh gateway") 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.flags.BoolVar(&c.omitDeprecatedTags, "omit-deprecated-tags", false, "In Consul 1.9.0 the format of metric tags for Envoy clusters was updated from consul.[service|dc|...] to "+ "consul.destination.[service|dc|...]. The old tags were preserved for backward compatibility,"+ "but can be disabled with this flag.") c.flags.StringVar(&c.prometheusBackendPort, "prometheus-backend-port", "", "Sets the backend port for the 'prometheus_backend' cluster that envoy_prometheus_bind_addr will point to. "+ "Without this flag, envoy_prometheus_bind_addr would point to the 'self_admin' cluster where Envoy metrics are exposed. "+ "The metrics merging feature in consul-k8s uses this to point to the merged metrics endpoint combining Envoy and service metrics. "+ "Only applicable when envoy_prometheus_bind_addr is set in proxy config.") c.flags.StringVar(&c.prometheusScrapePath, "prometheus-scrape-path", "/metrics", "Sets the path where Envoy will expose metrics on envoy_prometheus_bind_addr listener. "+ "For example, if envoy_prometheus_bind_addr is 0.0.0.0:20200, and this flag is "+ "set to /scrape-metrics, prometheus metrics would be scrapeable at "+ "0.0.0.0:20200/scrape-metrics. "+ "Only applicable when envoy_prometheus_bind_addr is set in proxy config.") c.http = &flags.HTTPFlags{} flags.Merge(c.flags, c.http.ClientFlags()) flags.Merge(c.flags, c.http.NamespaceFlags()) c.help = flags.Usage(help, c.flags) } // 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 api.ServiceAddress) bool { ifAddrs, err := net.InterfaceAddrs() if err != nil { return false } return canBindInternal(addr.Address, ifAddrs) } func (c *cmd) Run(args []string) int { if err := c.flags.Parse(args); err != nil { return 1 } // Setup Consul client var err error c.client, err = c.http.APIClient() if err != nil { c.UI.Error(fmt.Sprintf("Error connecting to Consul agent: %s", err)) return 1 } // TODO: refactor return c.run(c.flags.Args()) } func (c *cmd) run(args []string) int { // Fixup for deprecated mesh-gateway flag if c.meshGateway && c.gateway != "" { c.UI.Error("The mesh-gateway flag is deprecated and cannot be used alongside the gateway flag") return 1 } if c.meshGateway { c.gateway = meshGatewayVal } if c.exposeServers { if c.gateway != meshGatewayVal { c.UI.Error("'-expose-servers' can only be used for mesh gateways") return 1 } if !c.register { c.UI.Error("'-expose-servers' requires '-register'") return 1 } } // Gateway kind is set so that it is available even if not auto-registering the gateway if c.gateway != "" { kind, ok := supportedGateways[c.gateway] if !ok { c.UI.Error("Gateway must be one of: terminating, mesh, or ingress") return 1 } c.gatewayKind = kind if c.gatewaySvcName == "" { c.gatewaySvcName = string(c.gatewayKind) } } if c.proxyID == "" { switch { case c.sidecarFor != "": proxyID, err := proxyCmd.LookupProxyIDForSidecar(c.client, c.sidecarFor) if err != nil { c.UI.Error(err.Error()) return 1 } c.proxyID = proxyID case c.gateway != "" && !c.register: gatewaySvc, err := proxyCmd.LookupGatewayProxy(c.client, c.gatewayKind) if err != nil { c.UI.Error(err.Error()) return 1 } c.proxyID = gatewaySvc.ID c.gatewaySvcName = gatewaySvc.Service case c.gateway != "" && c.register: c.proxyID = c.gatewaySvcName } } if c.proxyID == "" { c.UI.Error("No proxy ID specified. One of -proxy-id, -sidecar-for, or -gateway is " + "required") return 1 } if c.register { if c.gateway == "" { c.UI.Error("Auto-Registration can only be used for gateways") return 1 } taggedAddrs := make(map[string]api.ServiceAddress) lanAddr := c.lanAddress.Value() if lanAddr.Address != "" { taggedAddrs[structs.TaggedAddressLAN] = lanAddr } wanAddr := c.wanAddress.Value() if wanAddr.Address != "" { taggedAddrs[structs.TaggedAddressWAN] = wanAddr } tcpCheckAddr := lanAddr.Address 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.value) > 0 { // override all default binding rules and just bind to the user-supplied addresses proxyConf = &api.AgentServiceConnectProxyConfig{ Config: map[string]interface{}{ "envoy_gateway_no_default_bind": true, "envoy_gateway_bind_addresses": c.bindAddresses.value, }, } } 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_gateway_no_default_bind": true, "envoy_gateway_bind_tagged_addresses": true, }, } } else if !canBind(lanAddr) && lanAddr.Address != "" { 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.Address)) return 1 } var meta map[string]string if c.exposeServers { meta = map[string]string{structs.MetaWANFederationKey: "1"} } svc := api.AgentServiceRegistration{ Kind: c.gatewayKind, Name: c.gatewaySvcName, ID: c.proxyID, Address: lanAddr.Address, Port: lanAddr.Port, Meta: meta, TaggedAddresses: taggedAddrs, Proxy: proxyConf, Check: &api.AgentServiceCheck{ Name: fmt.Sprintf("%s listening", c.gatewayKind), TCP: ipaddr.FormatAddressPort(tcpCheckAddr, lanAddr.Port), Interval: "10s", DeregisterCriticalServiceAfter: c.deregAfterCritical, }, } if err := c.client.Agent().ServiceRegister(&svc); err != nil { c.UI.Error(fmt.Sprintf("Error registering service %q: %s", svc.Name, err)) return 1 } if !c.bootstrap { // We need stdout to be reserved exclusively for the JSON blob, so // we omit logging this to Info which also writes to stdout. c.UI.Info(fmt.Sprintf("Registered service: %s", svc.Name)) } } // 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 c.UI.Output(string(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, args, 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) // api.NewClient normalizes some values (Token, Scheme) on the Config. if _, err := api.NewClient(httpCfg); err != nil { return nil, err } xdsAddr, err := c.xdsAddress(httpCfg) if err != nil { return nil, err } 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 proxySourceService := "" if c.sidecarFor != "" { cluster = c.sidecarFor proxySourceService = c.sidecarFor } else if c.gateway != "" && c.gatewaySvcName != "" { cluster = c.gatewaySvcName proxySourceService = c.gatewaySvcName } adminAccessLogPath := c.adminAccessLogPath if adminAccessLogPath == "" { adminAccessLogPath = DefaultAdminAccessLogPath } var caPEM string pems, err := tlsutil.LoadCAs(httpCfg.TLSConfig.CAFile, httpCfg.TLSConfig.CAPath) if err != nil { return nil, err } caPEM = strings.Replace(strings.Join(pems, ""), "\n", "\\n", -1) return &BootstrapTplArgs{ GRPC: xdsAddr, ProxyCluster: cluster, ProxyID: c.proxyID, ProxySourceService: proxySourceService, AgentCAPEM: caPEM, AdminAccessLogPath: adminAccessLogPath, AdminBindAddress: adminBindIP.String(), AdminBindPort: adminPort, Token: httpCfg.Token, LocalAgentClusterName: xds.LocalAgentClusterName, Namespace: httpCfg.Namespace, EnvoyVersion: c.envoyVersion, Datacenter: httpCfg.Datacenter, PrometheusBackendPort: c.prometheusBackendPort, PrometheusScrapePath: c.prometheusScrapePath, }, nil } func (c *cmd) generateConfig() ([]byte, error) { args, err := c.templateArgs() if err != nil { return nil, err } var bsCfg BootstrapConfig // Setup ready listener for ingress gateway to pass healthcheck if c.gatewayKind == api.ServiceKindIngressGateway { lanAddr := c.lanAddress.String() // Deal with possibility of address not being specified and defaulting to // ":443" if strings.HasPrefix(lanAddr, ":") { lanAddr = "127.0.0.1" + lanAddr } bsCfg.ReadyBindAddr = lanAddr } // 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 gateway") } if svc.Proxy.DestinationServiceName != "" { // Override cluster now we know the actual service name args.ProxyCluster = svc.Proxy.DestinationServiceName args.ProxySourceService = svc.Proxy.DestinationServiceName } else { // Set the source service name from the proxy's own registration args.ProxySourceService = svc.Service } if svc.Namespace != "" { // In most cases where namespaces are enabled this will already be set // correctly because the http client that fetched this will need to have // had the namespace set on it which is also how we initially populate // this. However in the case of "default" namespace being accessed because // there was no namespace argument, args.Namespace will be empty even // though Namespaces are actually being used and the namespace of the request was // inferred from the ACL token or defaulted to the "default" namespace. // Overriding it here ensures that we always set the Namespace arg if the // cluster is using namespaces regardless. args.Namespace = svc.Namespace } if svc.Datacenter != "" { // The agent will definitely have the definitive answer here. args.Datacenter = svc.Datacenter } if !c.disableCentralConfig { // Parse the bootstrap config if err := mapstructure.WeakDecode(svc.Proxy.Config, &bsCfg); err != nil { return nil, fmt.Errorf("failed parsing Proxy.Config: %s", err) } } return bsCfg.GenerateJSON(args, c.omitDeprecatedTags) } // TODO: make method a function func (c *cmd) xdsAddress(httpCfg *api.Config) (GRPC, error) { g := GRPC{} addr := c.grpcAddr if addr == "" { port, err := c.lookupXDSPort() 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 } addr = fmt.Sprintf("localhost:%v", port) } // TODO: parse addr as a url instead of strings.HasPrefix/TrimPrefix // 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:// switch { case strings.HasPrefix(strings.ToLower(addr), "https://"): g.AgentTLS = true case httpCfg.Scheme == "https": g.AgentTLS = 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. if grpcAddr := strings.TrimPrefix(addr, "unix://"); grpcAddr != addr { // Path to unix socket g.AgentSocket = grpcAddr } else { // Parse as host:port with option http prefix grpcAddr = strings.TrimPrefix(addr, "http://") grpcAddr = strings.TrimPrefix(grpcAddr, "https://") var err error var host string host, g.AgentPort, err = net.SplitHostPort(grpcAddr) if err != nil { return g, fmt.Errorf("Invalid Consul HTTP address: %s", err) } // 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", host) if err != nil { return g, fmt.Errorf("Failed to resolve agent address: %s", err) } g.AgentAddress = agentIP.String() } return g, nil } func (c *cmd) lookupXDSPort() (int, error) { self, err := c.client.Agent().Self() if err != nil { return 0, err } type response struct { XDS struct { Port int } } var resp response if err := mapstructure.Decode(self, &resp); err == nil && resp.XDS.Port != 0 { return resp.XDS.Port, nil } // Fallback to old API for the case where a new consul CLI is being used with // an older API version. 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_HTTP_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 `