package http import ( "bytes" "context" "encoding/json" "errors" "fmt" "io" "io/ioutil" "net" "net/http" "net/textproto" "net/url" "os" "strings" "time" "github.com/NYTimes/gziphandler" assetfs "github.com/elazarl/go-bindata-assetfs" "github.com/hashicorp/errwrap" cleanhttp "github.com/hashicorp/go-cleanhttp" sockaddr "github.com/hashicorp/go-sockaddr" "github.com/hashicorp/vault/helper/namespace" "github.com/hashicorp/vault/sdk/helper/consts" "github.com/hashicorp/vault/sdk/helper/jsonutil" "github.com/hashicorp/vault/sdk/helper/parseutil" "github.com/hashicorp/vault/sdk/helper/pathmanager" "github.com/hashicorp/vault/sdk/logical" "github.com/hashicorp/vault/vault" ) const ( // WrapTTLHeaderName is the name of the header containing a directive to // wrap the response WrapTTLHeaderName = "X-Vault-Wrap-TTL" // WrapFormatHeaderName is the name of the header containing the format to // wrap in; has no effect if the wrap TTL is not set WrapFormatHeaderName = "X-Vault-Wrap-Format" // NoRequestForwardingHeaderName is the name of the header telling Vault // not to use request forwarding NoRequestForwardingHeaderName = "X-Vault-No-Request-Forwarding" // MFAHeaderName represents the HTTP header which carries the credentials // required to perform MFA on any path. MFAHeaderName = "X-Vault-MFA" // canonicalMFAHeaderName is the MFA header value's format in the request // headers. Do not alter the casing of this string. canonicalMFAHeaderName = "X-Vault-Mfa" // PolicyOverrideHeaderName is the header set to request overriding // soft-mandatory Sentinel policies. PolicyOverrideHeaderName = "X-Vault-Policy-Override" // DefaultMaxRequestSize is the default maximum accepted request size. This // is to prevent a denial of service attack where no Content-Length is // provided and the server is fed ever more data until it exhausts memory. // Can be overridden per listener. DefaultMaxRequestSize = 32 * 1024 * 1024 ) var ( // Set to false by stub_asset if the ui build tag isn't enabled uiBuiltIn = true // perfStandbyAlwaysForwardPaths is used to check a requested path against // the always forward list perfStandbyAlwaysForwardPaths = pathmanager.New() alwaysRedirectPaths = pathmanager.New() injectDataIntoTopRoutes = []string{ "/v1/sys/audit", "/v1/sys/audit/", "/v1/sys/audit-hash/", "/v1/sys/auth", "/v1/sys/auth/", "/v1/sys/config/cors", "/v1/sys/config/auditing/request-headers/", "/v1/sys/config/auditing/request-headers", "/v1/sys/capabilities", "/v1/sys/capabilities-accessor", "/v1/sys/capabilities-self", "/v1/sys/key-status", "/v1/sys/mounts", "/v1/sys/mounts/", "/v1/sys/policy", "/v1/sys/policy/", "/v1/sys/rekey/backup", "/v1/sys/rekey/recovery-key-backup", "/v1/sys/remount", "/v1/sys/rotate", "/v1/sys/wrapping/wrap", } ) func init() { alwaysRedirectPaths.AddPaths([]string{ "sys/storage/raft/snapshot", "sys/storage/raft/snapshot-force", }) } // Handler returns an http.Handler for the API. This can be used on // its own to mount the Vault API within another web server. func Handler(props *vault.HandlerProperties) http.Handler { core := props.Core // Create the muxer to handle the actual endpoints mux := http.NewServeMux() // Handle pprof paths mux.Handle("/v1/sys/pprof/", handleLogicalNoForward(core)) mux.Handle("/v1/sys/init", handleSysInit(core)) mux.Handle("/v1/sys/seal-status", handleSysSealStatus(core)) mux.Handle("/v1/sys/seal", handleSysSeal(core)) mux.Handle("/v1/sys/step-down", handleRequestForwarding(core, handleSysStepDown(core))) mux.Handle("/v1/sys/unseal", handleSysUnseal(core)) mux.Handle("/v1/sys/leader", handleSysLeader(core)) mux.Handle("/v1/sys/health", handleSysHealth(core)) mux.Handle("/v1/sys/generate-root/attempt", handleRequestForwarding(core, handleSysGenerateRootAttempt(core, vault.GenerateStandardRootTokenStrategy))) mux.Handle("/v1/sys/generate-root/update", handleRequestForwarding(core, handleSysGenerateRootUpdate(core, vault.GenerateStandardRootTokenStrategy))) mux.Handle("/v1/sys/rekey/init", handleRequestForwarding(core, handleSysRekeyInit(core, false))) mux.Handle("/v1/sys/rekey/update", handleRequestForwarding(core, handleSysRekeyUpdate(core, false))) mux.Handle("/v1/sys/rekey/verify", handleRequestForwarding(core, handleSysRekeyVerify(core, false))) mux.Handle("/v1/sys/rekey-recovery-key/init", handleRequestForwarding(core, handleSysRekeyInit(core, true))) mux.Handle("/v1/sys/rekey-recovery-key/update", handleRequestForwarding(core, handleSysRekeyUpdate(core, true))) mux.Handle("/v1/sys/rekey-recovery-key/verify", handleRequestForwarding(core, handleSysRekeyVerify(core, true))) mux.Handle("/v1/sys/storage/raft/join", handleSysRaftJoin(core)) for _, path := range injectDataIntoTopRoutes { mux.Handle(path, handleRequestForwarding(core, handleLogicalWithInjector(core))) } mux.Handle("/v1/sys/", handleRequestForwarding(core, handleLogical(core))) mux.Handle("/v1/", handleRequestForwarding(core, handleLogical(core))) if core.UIEnabled() == true { if uiBuiltIn { mux.Handle("/ui/", http.StripPrefix("/ui/", gziphandler.GzipHandler(handleUIHeaders(core, handleUI(http.FileServer(&UIAssetWrapper{FileSystem: assetFS()})))))) mux.Handle("/robots.txt", gziphandler.GzipHandler(handleUIHeaders(core, handleUI(http.FileServer(&UIAssetWrapper{FileSystem: assetFS()}))))) } else { mux.Handle("/ui/", handleUIHeaders(core, handleUIStub())) } mux.Handle("/ui", handleUIRedirect()) mux.Handle("/", handleUIRedirect()) } additionalRoutes(mux, core) // Wrap the handler in another handler to trigger all help paths. helpWrappedHandler := wrapHelpHandler(mux, core) corsWrappedHandler := wrapCORSHandler(helpWrappedHandler, core) genericWrappedHandler := genericWrapping(core, corsWrappedHandler, props) // Wrap the handler with PrintablePathCheckHandler to check for non-printable // characters in the request path. printablePathCheckHandler := genericWrappedHandler if !props.DisablePrintableCheck { printablePathCheckHandler = cleanhttp.PrintablePathCheckHandler(genericWrappedHandler, nil) } return printablePathCheckHandler } // wrapGenericHandler wraps the handler with an extra layer of handler where // tasks that should be commonly handled for all the requests and/or responses // are performed. func wrapGenericHandler(core *vault.Core, h http.Handler, maxRequestSize int64, maxRequestDuration time.Duration) http.Handler { if maxRequestDuration == 0 { maxRequestDuration = vault.DefaultMaxRequestDuration } return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { // Set the Cache-Control header for all the responses returned // by Vault w.Header().Set("Cache-Control", "no-store") // Start with the request context ctx := r.Context() var cancelFunc context.CancelFunc // Add our timeout ctx, cancelFunc = context.WithTimeout(ctx, maxRequestDuration) // Add a size limiter if desired if maxRequestSize > 0 { ctx = context.WithValue(ctx, "max_request_size", maxRequestSize) } ctx = context.WithValue(ctx, "original_request_path", r.URL.Path) r = r.WithContext(ctx) switch { case strings.HasPrefix(r.URL.Path, "/v1/"): newR, status := adjustRequest(core, r) if status != 0 { respondError(w, status, nil) cancelFunc() return } r = newR case strings.HasPrefix(r.URL.Path, "/ui"), r.URL.Path == "/robots.txt", r.URL.Path == "/": default: respondError(w, http.StatusNotFound, nil) cancelFunc() return } h.ServeHTTP(w, r) cancelFunc() return }) } func WrapForwardedForHandler(h http.Handler, authorizedAddrs []*sockaddr.SockAddrMarshaler, rejectNotPresent, rejectNonAuthz bool, hopSkips int) http.Handler { return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { headers, headersOK := r.Header[textproto.CanonicalMIMEHeaderKey("X-Forwarded-For")] if !headersOK || len(headers) == 0 { if !rejectNotPresent { h.ServeHTTP(w, r) return } respondError(w, http.StatusBadRequest, fmt.Errorf("missing x-forwarded-for header and configured to reject when not present")) return } host, port, err := net.SplitHostPort(r.RemoteAddr) if err != nil { // If not rejecting treat it like we just don't have a valid // header because we can't do a comparison against an address we // can't understand if !rejectNotPresent { h.ServeHTTP(w, r) return } respondError(w, http.StatusBadRequest, errwrap.Wrapf("error parsing client hostport: {{err}}", err)) return } addr, err := sockaddr.NewIPAddr(host) if err != nil { // We treat this the same as the case above if !rejectNotPresent { h.ServeHTTP(w, r) return } respondError(w, http.StatusBadRequest, errwrap.Wrapf("error parsing client address: {{err}}", err)) return } var found bool for _, authz := range authorizedAddrs { if authz.Contains(addr) { found = true break } } if !found { // If we didn't find it and aren't configured to reject, simply // don't trust it if !rejectNonAuthz { h.ServeHTTP(w, r) return } respondError(w, http.StatusBadRequest, fmt.Errorf("client address not authorized for x-forwarded-for and configured to reject connection")) return } // At this point we have at least one value and it's authorized // Split comma separated ones, which are common. This brings it in line // to the multiple-header case. var acc []string for _, header := range headers { vals := strings.Split(header, ",") for _, v := range vals { acc = append(acc, strings.TrimSpace(v)) } } indexToUse := len(acc) - 1 - hopSkips if indexToUse < 0 { // This is likely an error in either configuration or other // infrastructure. We could either deny the request, or we // could simply not trust the value. Denying the request is // "safer" since if this logic is configured at all there may // be an assumption it can always be trusted. Given that we can // deny accepting the request at all if it's not from an // authorized address, if we're at this point the address is // authorized (or we've turned off explicit rejection) and we // should assume that what comes in should be properly // formatted. respondError(w, http.StatusBadRequest, fmt.Errorf("malformed x-forwarded-for configuration or request, hops to skip (%d) would skip before earliest chain link (chain length %d)", hopSkips, len(headers))) return } r.RemoteAddr = net.JoinHostPort(acc[indexToUse], port) h.ServeHTTP(w, r) return }) } // A lookup on a token that is about to expire returns nil, which means by the // time we can validate a wrapping token lookup will return nil since it will // be revoked after the call. So we have to do the validation here. func wrappingVerificationFunc(ctx context.Context, core *vault.Core, req *logical.Request) error { if req == nil { return fmt.Errorf("invalid request") } valid, err := core.ValidateWrappingToken(ctx, req) if err != nil { return errwrap.Wrapf("error validating wrapping token: {{err}}", err) } if !valid { return consts.ErrInvalidWrappingToken } return nil } // stripPrefix is a helper to strip a prefix from the path. It will // return false from the second return value if it the prefix doesn't exist. func stripPrefix(prefix, path string) (string, bool) { if !strings.HasPrefix(path, prefix) { return "", false } path = path[len(prefix):] if path == "" { return "", false } return path, true } func handleUIHeaders(core *vault.Core, h http.Handler) http.Handler { return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) { header := w.Header() userHeaders, err := core.UIHeaders() if err != nil { respondError(w, http.StatusInternalServerError, err) return } if userHeaders != nil { for k := range userHeaders { v := userHeaders.Get(k) header.Set(k, v) } } h.ServeHTTP(w, req) }) } func handleUI(h http.Handler) http.Handler { return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) { // The fileserver handler strips trailing slashes and does a redirect. // We don't want the redirect to happen so we preemptively trim the slash // here. req.URL.Path = strings.TrimSuffix(req.URL.Path, "/") h.ServeHTTP(w, req) return }) } func handleUIStub() http.Handler { stubHTML := `

Vault UI is not available in this binary.

To get Vault UI do one of the following:

` return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) { w.Write([]byte(stubHTML)) }) } func handleUIRedirect() http.Handler { return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) { http.Redirect(w, req, "/ui/", 307) return }) } type UIAssetWrapper struct { FileSystem *assetfs.AssetFS } func (fs *UIAssetWrapper) Open(name string) (http.File, error) { file, err := fs.FileSystem.Open(name) if err == nil { return file, nil } // serve index.html instead of 404ing if err == os.ErrNotExist { return fs.FileSystem.Open("index.html") } return nil, err } func parseQuery(values url.Values) map[string]interface{} { data := map[string]interface{}{} for k, v := range values { // Skip the help key as this is a reserved parameter if k == "help" { continue } switch { case len(v) == 0: case len(v) == 1: data[k] = v[0] default: data[k] = v } } if len(data) > 0 { return data } return nil } func parseRequest(core *vault.Core, r *http.Request, w http.ResponseWriter, out interface{}) (io.ReadCloser, error) { // Limit the maximum number of bytes to MaxRequestSize to protect // against an indefinite amount of data being read. reader := r.Body ctx := r.Context() maxRequestSize := ctx.Value("max_request_size") if maxRequestSize != nil { max, ok := maxRequestSize.(int64) if !ok { return nil, errors.New("could not parse max_request_size from request context") } if max > 0 { reader = http.MaxBytesReader(w, r.Body, max) } } var origBody io.ReadWriter if core.PerfStandby() { // Since we're checking PerfStandby here we key on origBody being nil // or not later, so we need to always allocate so it's non-nil origBody = new(bytes.Buffer) reader = ioutil.NopCloser(io.TeeReader(reader, origBody)) } err := jsonutil.DecodeJSONFromReader(reader, out) if err != nil && err != io.EOF { return nil, errwrap.Wrapf("failed to parse JSON input: {{err}}", err) } if origBody != nil { return ioutil.NopCloser(origBody), err } return nil, err } // handleRequestForwarding determines whether to forward a request or not, // falling back on the older behavior of redirecting the client func handleRequestForwarding(core *vault.Core, handler http.Handler) http.Handler { return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { // If we are a performance standby we can handle the request. if core.PerfStandby() { ns, err := namespace.FromContext(r.Context()) if err != nil { respondError(w, http.StatusBadRequest, err) return } path := ns.TrimmedPath(r.URL.Path[len("/v1/"):]) switch { case !perfStandbyAlwaysForwardPaths.HasPath(path) && !alwaysRedirectPaths.HasPath(path): handler.ServeHTTP(w, r) return case strings.HasPrefix(path, "auth/token/create/"): isBatch, err := core.IsBatchTokenCreationRequest(r.Context(), path) if err == nil && isBatch { handler.ServeHTTP(w, r) return } } } // Note: in an HA setup, this call will also ensure that connections to // the leader are set up, as that happens once the advertised cluster // values are read during this function isLeader, leaderAddr, _, err := core.Leader() if err != nil { if err == vault.ErrHANotEnabled { // Standalone node, serve request normally handler.ServeHTTP(w, r) return } // Some internal error occurred respondError(w, http.StatusInternalServerError, err) return } if isLeader { // No forwarding needed, we're leader handler.ServeHTTP(w, r) return } if leaderAddr == "" { respondError(w, http.StatusInternalServerError, fmt.Errorf("local node not active but active cluster node not found")) return } forwardRequest(core, w, r) return }) } func forwardRequest(core *vault.Core, w http.ResponseWriter, r *http.Request) { if r.Header.Get(vault.IntNoForwardingHeaderName) != "" { respondStandby(core, w, r.URL) return } if r.Header.Get(NoRequestForwardingHeaderName) != "" { // Forwarding explicitly disabled, fall back to previous behavior core.Logger().Debug("handleRequestForwarding: forwarding disabled by client request") respondStandby(core, w, r.URL) return } ns, err := namespace.FromContext(r.Context()) if err != nil { respondError(w, http.StatusBadRequest, err) return } path := ns.TrimmedPath(r.URL.Path[len("/v1/"):]) if alwaysRedirectPaths.HasPath(path) { respondStandby(core, w, r.URL) return } // Attempt forwarding the request. If we cannot forward -- perhaps it's // been disabled on the active node -- this will return with an // ErrCannotForward and we simply fall back statusCode, header, retBytes, err := core.ForwardRequest(r) if err != nil { if err == vault.ErrCannotForward { core.Logger().Debug("cannot forward request (possibly disabled on active node), falling back") } else { core.Logger().Error("forward request error", "error", err) } // Fall back to redirection respondStandby(core, w, r.URL) return } if header != nil { for k, v := range header { w.Header()[k] = v } } w.WriteHeader(statusCode) w.Write(retBytes) } // request is a helper to perform a request and properly exit in the // case of an error. func request(core *vault.Core, w http.ResponseWriter, rawReq *http.Request, r *logical.Request) (*logical.Response, bool, bool) { resp, err := core.HandleRequest(rawReq.Context(), r) if r.LastRemoteWAL() > 0 && !vault.WaitUntilWALShipped(rawReq.Context(), core, r.LastRemoteWAL()) { if resp == nil { resp = &logical.Response{} } resp.AddWarning("Timeout hit while waiting for local replicated cluster to apply primary's write; this client may encounter stale reads of values written during this operation.") } if errwrap.Contains(err, consts.ErrStandby.Error()) { respondStandby(core, w, rawReq.URL) return resp, false, false } if err != nil && errwrap.Contains(err, logical.ErrPerfStandbyPleaseForward.Error()) { return nil, false, true } if resp != nil && len(resp.Headers) > 0 { // Set this here so it will take effect regardless of any other type of // response processing header := w.Header() for k, v := range resp.Headers { for _, h := range v { header.Add(k, h) } } switch { case resp.Secret != nil, resp.Auth != nil, len(resp.Data) > 0, resp.Redirect != "", len(resp.Warnings) > 0, resp.WrapInfo != nil: // Nothing, resp has data default: // We have an otherwise totally empty response except for headers, // so nil out the response now that the headers are written out resp = nil } } // If vault's core has already written to the response writer do not add any // additional output. Headers have already been sent. If the response writer // is set but has not been written to it likely means there was some kind of // error if r.ResponseWriter != nil && r.ResponseWriter.Written() { return nil, true, false } if respondErrorCommon(w, r, resp, err) { return resp, false, false } return resp, true, false } // respondStandby is used to trigger a redirect in the case that this Vault is currently a hot standby func respondStandby(core *vault.Core, w http.ResponseWriter, reqURL *url.URL) { // Request the leader address _, redirectAddr, _, err := core.Leader() if err != nil { if err == vault.ErrHANotEnabled { // Standalone node, serve 503 err = errors.New("node is not active") respondError(w, http.StatusServiceUnavailable, err) return } respondError(w, http.StatusInternalServerError, err) return } // If there is no leader, generate a 503 error if redirectAddr == "" { err = errors.New("no active Vault instance found") respondError(w, http.StatusServiceUnavailable, err) return } // Parse the redirect location redirectURL, err := url.Parse(redirectAddr) if err != nil { respondError(w, http.StatusInternalServerError, err) return } // Generate a redirect URL finalURL := url.URL{ Scheme: redirectURL.Scheme, Host: redirectURL.Host, Path: reqURL.Path, RawQuery: reqURL.RawQuery, } // Ensure there is a scheme, default to https if finalURL.Scheme == "" { finalURL.Scheme = "https" } // If we have an address, redirect! We use a 307 code // because we don't actually know if its permanent and // the request method should be preserved. w.Header().Set("Location", finalURL.String()) w.WriteHeader(307) } // getTokenFromReq parse headers of the incoming request to extract token if // present it accepts Authorization Bearer (RFC6750) and X-Vault-Token header. // Returns true if the token was sourced from a Bearer header. func getTokenFromReq(r *http.Request) (string, bool) { if token := r.Header.Get(consts.AuthHeaderName); token != "" { return token, false } if headers, ok := r.Header["Authorization"]; ok { // Reference for Authorization header format: https://tools.ietf.org/html/rfc7236#section-3 // If string does not start by 'Bearer ', it is not one we would use, // but might be used by plugins for _, v := range headers { if !strings.HasPrefix(v, "Bearer ") { continue } return strings.TrimSpace(v[7:]), true } } return "", false } // requestAuth adds the token to the logical.Request if it exists. func requestAuth(core *vault.Core, r *http.Request, req *logical.Request) (*logical.Request, error) { // Attach the header value if we have it token, fromAuthzHeader := getTokenFromReq(r) if token != "" { req.ClientToken = token req.ClientTokenSource = logical.ClientTokenFromVaultHeader if fromAuthzHeader { req.ClientTokenSource = logical.ClientTokenFromAuthzHeader } // Also attach the accessor if we have it. This doesn't fail if it // doesn't exist because the request may be to an unauthenticated // endpoint/login endpoint where a bad current token doesn't matter, or // a token from a Vault version pre-accessors. We ignore errors for // JWTs. te, err := core.LookupToken(r.Context(), token) if err != nil { dotCount := strings.Count(token, ".") // If we have two dots but the second char is a dot it's a vault // token of the form s.SOMETHING.nsid, not a JWT if dotCount != 2 || dotCount == 2 && token[1] == '.' { return req, err } } if err == nil && te != nil { req.ClientTokenAccessor = te.Accessor req.ClientTokenRemainingUses = te.NumUses req.SetTokenEntry(te) } } return req, nil } func requestPolicyOverride(r *http.Request, req *logical.Request) error { raw := r.Header.Get(PolicyOverrideHeaderName) if raw == "" { return nil } override, err := parseutil.ParseBool(raw) if err != nil { return err } req.PolicyOverride = override return nil } // requestWrapInfo adds the WrapInfo value to the logical.Request if wrap info exists func requestWrapInfo(r *http.Request, req *logical.Request) (*logical.Request, error) { // First try for the header value wrapTTL := r.Header.Get(WrapTTLHeaderName) if wrapTTL == "" { return req, nil } // If it has an allowed suffix parse as a duration string dur, err := parseutil.ParseDurationSecond(wrapTTL) if err != nil { return req, err } if int64(dur) < 0 { return req, fmt.Errorf("requested wrap ttl cannot be negative") } req.WrapInfo = &logical.RequestWrapInfo{ TTL: dur, } wrapFormat := r.Header.Get(WrapFormatHeaderName) switch wrapFormat { case "jwt": req.WrapInfo.Format = "jwt" } return req, nil } // parseMFAHeader parses the MFAHeaderName in the request headers and organizes // them with MFA method name as the index. func parseMFAHeader(req *logical.Request) error { if req == nil { return fmt.Errorf("request is nil") } if req.Headers == nil { return nil } // Reset and initialize the credentials in the request req.MFACreds = make(map[string][]string) for _, mfaHeaderValue := range req.Headers[canonicalMFAHeaderName] { // Skip the header with no value in it if mfaHeaderValue == "" { continue } // Handle the case where only method name is mentioned and no value // is supplied if !strings.Contains(mfaHeaderValue, ":") { // Mark the presence of method name, but set an empty set to it // indicating that there were no values supplied for the method if req.MFACreds[mfaHeaderValue] == nil { req.MFACreds[mfaHeaderValue] = []string{} } continue } shardSplits := strings.SplitN(mfaHeaderValue, ":", 2) if shardSplits[0] == "" { return fmt.Errorf("invalid data in header %q; missing method name", MFAHeaderName) } if shardSplits[1] == "" { return fmt.Errorf("invalid data in header %q; missing method value", MFAHeaderName) } req.MFACreds[shardSplits[0]] = append(req.MFACreds[shardSplits[0]], shardSplits[1]) } return nil } func respondError(w http.ResponseWriter, status int, err error) { logical.RespondError(w, status, err) } func respondErrorCommon(w http.ResponseWriter, req *logical.Request, resp *logical.Response, err error) bool { statusCode, newErr := logical.RespondErrorCommon(req, resp, err) if newErr == nil && statusCode == 0 { return false } respondError(w, statusCode, newErr) return true } func respondOk(w http.ResponseWriter, body interface{}) { w.Header().Set("Content-Type", "application/json") if body == nil { w.WriteHeader(http.StatusNoContent) } else { w.WriteHeader(http.StatusOK) enc := json.NewEncoder(w) enc.Encode(body) } }