node: allow websocket and HTTP on the same port (#20810)

This change makes it possible to run geth with JSON-RPC over HTTP and
WebSocket on the same TCP port. The default port for WebSocket
is still 8546. 

    geth --rpc --rpcport 8545 --ws --wsport 8545

This also removes a lot of deprecated API surface from package rpc.
The rpc package is now purely about serving JSON-RPC and no longer
provides a way to start an HTTP server.

rpc/http.go

@@ -25,14 +25,9 @@ import (
 	"io"
 	"io/ioutil"
 	"mime"
-	"net"
 	"net/http"
-	"strings"
 	"sync"
 	"time"
-
-	"github.com/ethereum/go-ethereum/log"
-	"github.com/rs/cors"
 )
 
 const (
@@ -209,37 +204,6 @@ func (t *httpServerConn) RemoteAddr() string {
 // SetWriteDeadline does nothing and always returns nil.
 func (t *httpServerConn) SetWriteDeadline(time.Time) error { return nil }
 
-// NewHTTPServer creates a new HTTP RPC server around an API provider.
-//
-// Deprecated: Server implements http.Handler
-func NewHTTPServer(cors []string, vhosts []string, timeouts HTTPTimeouts, srv http.Handler) *http.Server {
-	// Wrap the CORS-handler within a host-handler
-	handler := newCorsHandler(srv, cors)
-	handler = newVHostHandler(vhosts, handler)
-	handler = newGzipHandler(handler)
-
-	// Make sure timeout values are meaningful
-	if timeouts.ReadTimeout < time.Second {
-		log.Warn("Sanitizing invalid HTTP read timeout", "provided", timeouts.ReadTimeout, "updated", DefaultHTTPTimeouts.ReadTimeout)
-		timeouts.ReadTimeout = DefaultHTTPTimeouts.ReadTimeout
-	}
-	if timeouts.WriteTimeout < time.Second {
-		log.Warn("Sanitizing invalid HTTP write timeout", "provided", timeouts.WriteTimeout, "updated", DefaultHTTPTimeouts.WriteTimeout)
-		timeouts.WriteTimeout = DefaultHTTPTimeouts.WriteTimeout
-	}
-	if timeouts.IdleTimeout < time.Second {
-		log.Warn("Sanitizing invalid HTTP idle timeout", "provided", timeouts.IdleTimeout, "updated", DefaultHTTPTimeouts.IdleTimeout)
-		timeouts.IdleTimeout = DefaultHTTPTimeouts.IdleTimeout
-	}
-	// Bundle and start the HTTP server
-	return &http.Server{
-		Handler:      handler,
-		ReadTimeout:  timeouts.ReadTimeout,
-		WriteTimeout: timeouts.WriteTimeout,
-		IdleTimeout:  timeouts.IdleTimeout,
-	}
-}
-
 // ServeHTTP serves JSON-RPC requests over HTTP.
 func (s *Server) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	// Permit dumb empty requests for remote health-checks (AWS)
@@ -296,64 +260,3 @@ func validateRequest(r *http.Request) (int, error) {
 	err := fmt.Errorf("invalid content type, only %s is supported", contentType)
 	return http.StatusUnsupportedMediaType, err
 }
-
-func newCorsHandler(srv http.Handler, allowedOrigins []string) http.Handler {
-	// disable CORS support if user has not specified a custom CORS configuration
-	if len(allowedOrigins) == 0 {
-		return srv
-	}
-	c := cors.New(cors.Options{
-		AllowedOrigins: allowedOrigins,
-		AllowedMethods: []string{http.MethodPost, http.MethodGet},
-		MaxAge:         600,
-		AllowedHeaders: []string{"*"},
-	})
-	return c.Handler(srv)
-}
-
-// virtualHostHandler is a handler which validates the Host-header of incoming requests.
-// The virtualHostHandler can prevent DNS rebinding attacks, which do not utilize CORS-headers,
-// since they do in-domain requests against the RPC api. Instead, we can see on the Host-header
-// which domain was used, and validate that against a whitelist.
-type virtualHostHandler struct {
-	vhosts map[string]struct{}
-	next   http.Handler
-}
-
-// ServeHTTP serves JSON-RPC requests over HTTP, implements http.Handler
-func (h *virtualHostHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
-	// if r.Host is not set, we can continue serving since a browser would set the Host header
-	if r.Host == "" {
-		h.next.ServeHTTP(w, r)
-		return
-	}
-	host, _, err := net.SplitHostPort(r.Host)
-	if err != nil {
-		// Either invalid (too many colons) or no port specified
-		host = r.Host
-	}
-	if ipAddr := net.ParseIP(host); ipAddr != nil {
-		// It's an IP address, we can serve that
-		h.next.ServeHTTP(w, r)
-		return
-
-	}
-	// Not an IP address, but a hostname. Need to validate
-	if _, exist := h.vhosts["*"]; exist {
-		h.next.ServeHTTP(w, r)
-		return
-	}
-	if _, exist := h.vhosts[host]; exist {
-		h.next.ServeHTTP(w, r)
-		return
-	}
-	http.Error(w, "invalid host specified", http.StatusForbidden)
-}
-
-func newVHostHandler(vhosts []string, next http.Handler) http.Handler {
-	vhostMap := make(map[string]struct{})
-	for _, allowedHost := range vhosts {
-		vhostMap[strings.ToLower(allowedHost)] = struct{}{}
-	}
-	return &virtualHostHandler{vhostMap, next}
-}