node: support expressive origin rules in ws.origins (#21481)

* Only compare hostnames in ws.origins

Also using a helper function for ToLower consolidates all preparation steps in one function for more maintainable consistency.

Spaces => tabs

Remove a semicolon

Add space at start of comment

Remove parens around conditional

Handle case wehre parsed hostname is empty

When passing a single word like "localhost" the parsed hostname is an empty string. Handle this and the error-parsing case together as default, and the nonempty hostname case in the conditional.

Refactor with new originIsAllowed functions

Adds originIsAllowed() & ruleAllowsOrigin(); removes prepOriginForComparison

Remove blank line

Added tests for simple allowed-orign rule

which does not specify a protocol or port, just a hostname

Fix copy-paste: `:=` => `=`

Remove parens around conditional

Remove autoadded whitespace on blank lines

Compare scheme, hostname, and port with rule

if the rule specifies those portions.

Remove one autoadded trailing whitespace

Better handle case where only origin host is given

e.g. "localhost"

Remove parens around conditional

Refactor: attemptWebsocketConnectionFromOrigin DRY

Include return type on helper function

Provide srv obj in helper fn

Provide srv to helper fn

Remove stray underscore

Remove blank line

parent 93e666b4c1e7e49b8406dc83ed93f4a02ea49ac1
author wbt <wbt@users.noreply.github.com> 1598559718 -0400
committer Martin Holst Swende <martin@swende.se> 1605602257 +0100
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Refactor: drop err var for more concise test lines

Add several tests for new WebSocket origin checks

Remove autoadded whitespace on blank lines

Restore TestWebsocketOrigins originally-named test

and rename the others to be helpers rather than full tests

Remove autoadded whitespace on blank line

Temporarily comment out new test sets

Uncomment test around origin rule with scheme

Remove tests without scheme on browser origin

per https://github.com/ethereum/go-ethereum/pull/21481/files#r479371498

Uncomment tests with port; remove some blank lines

Handle when browser does not specify scheme/port

Uncomment test for including scheme & port in rule

Add IP tests

* node: more tests + table-driven, ws origin changes

Co-authored-by: Martin Holst Swende <martin@swende.se>

node/rpcstack_test.go

@@ -19,6 +19,7 @@ package node
 import (
 	"bytes"
 	"net/http"
+	"strings"
 	"testing"
 
 	"github.com/ethereum/go-ethereum/internal/testlog"
@@ -52,25 +53,104 @@ func TestVhosts(t *testing.T) {
 	assert.Equal(t, resp2.StatusCode, http.StatusForbidden)
 }
 
-// TestWebsocketOrigins makes sure the websocket origins are properly handled on the websocket server.
-func TestWebsocketOrigins(t *testing.T) {
-	srv := createAndStartServer(t, httpConfig{}, true, wsConfig{Origins: []string{"test"}})
-	defer srv.stop()
+type originTest struct {
+	spec    string
+	expOk   []string
+	expFail []string
+}
 
-	dialer := websocket.DefaultDialer
-	_, _, err := dialer.Dial("ws://"+srv.listenAddr(), http.Header{
-		"Content-type":          []string{"application/json"},
-		"Sec-WebSocket-Version": []string{"13"},
-		"Origin":                []string{"test"},
-	})
-	assert.NoError(t, err)
+// splitAndTrim splits input separated by a comma
+// and trims excessive white space from the substrings.
+// Copied over from flags.go
+func splitAndTrim(input string) (ret []string) {
+	l := strings.Split(input, ",")
+	for _, r := range l {
+		r = strings.TrimSpace(r)
+		if len(r) > 0 {
+			ret = append(ret, r)
+		}
+	}
+	return ret
+}
 
-	_, _, err = dialer.Dial("ws://"+srv.listenAddr(), http.Header{
-		"Content-type":          []string{"application/json"},
-		"Sec-WebSocket-Version": []string{"13"},
-		"Origin":                []string{"bad"},
-	})
-	assert.Error(t, err)
+// TestWebsocketOrigins makes sure the websocket origins are properly handled on the websocket server.
+func TestWebsocketOrigins(t *testing.T) {
+	tests := []originTest{
+		{
+			spec: "*", // allow all
+			expOk: []string{"", "http://test", "https://test", "http://test:8540", "https://test:8540",
+				"http://test.com", "https://foo.test", "http://testa", "http://atestb:8540", "https://atestb:8540"},
+		},
+		{
+			spec:    "test",
+			expOk:   []string{"http://test", "https://test", "http://test:8540", "https://test:8540"},
+			expFail: []string{"http://test.com", "https://foo.test", "http://testa", "http://atestb:8540", "https://atestb:8540"},
+		},
+		// scheme tests
+		{
+			spec:  "https://test",
+			expOk: []string{"https://test", "https://test:9999"},
+			expFail: []string{
+				"test",                                // no scheme, required by spec
+				"http://test",                         // wrong scheme
+				"http://test.foo", "https://a.test.x", // subdomain variatoins
+				"http://testx:8540", "https://xtest:8540"},
+		},
+		// ip tests
+		{
+			spec:  "https://12.34.56.78",
+			expOk: []string{"https://12.34.56.78", "https://12.34.56.78:8540"},
+			expFail: []string{
+				"http://12.34.56.78",     // wrong scheme
+				"http://12.34.56.78:443", // wrong scheme
+				"http://1.12.34.56.78",   // wrong 'domain name'
+				"http://12.34.56.78.a",   // wrong 'domain name'
+				"https://87.65.43.21", "http://87.65.43.21:8540", "https://87.65.43.21:8540"},
+		},
+		// port tests
+		{
+			spec:  "test:8540",
+			expOk: []string{"http://test:8540", "https://test:8540"},
+			expFail: []string{
+				"http://test", "https://test", // spec says port required
+				"http://test:8541", "https://test:8541", // wrong port
+				"http://bad", "https://bad", "http://bad:8540", "https://bad:8540"},
+		},
+		// scheme and port
+		{
+			spec:  "https://test:8540",
+			expOk: []string{"https://test:8540"},
+			expFail: []string{
+				"https://test",                          // missing port
+				"http://test",                           // missing port, + wrong scheme
+				"http://test:8540",                      // wrong scheme
+				"http://test:8541", "https://test:8541", // wrong port
+				"http://bad", "https://bad", "http://bad:8540", "https://bad:8540"},
+		},
+		// several allowed origins
+		{
+			spec: "localhost,http://127.0.0.1",
+			expOk: []string{"localhost", "http://localhost", "https://localhost:8443",
+				"http://127.0.0.1", "http://127.0.0.1:8080"},
+			expFail: []string{
+				"https://127.0.0.1", // wrong scheme
+				"http://bad", "https://bad", "http://bad:8540", "https://bad:8540"},
+		},
+	}
+	for _, tc := range tests {
+		srv := createAndStartServer(t, httpConfig{}, true, wsConfig{Origins: splitAndTrim(tc.spec)})
+		for _, origin := range tc.expOk {
+			if err := attemptWebsocketConnectionFromOrigin(t, srv, origin); err != nil {
+				t.Errorf("spec '%v', origin '%v': expected ok, got %v", tc.spec, origin, err)
+			}
+		}
+		for _, origin := range tc.expFail {
+			if err := attemptWebsocketConnectionFromOrigin(t, srv, origin); err == nil {
+				t.Errorf("spec '%v', origin '%v': expected not to allow,  got ok", tc.spec, origin)
+			}
+		}
+		srv.stop()
+	}
 }
 
 // TestIsWebsocket tests if an incoming websocket upgrade request is handled properly.
@@ -103,6 +183,17 @@ func createAndStartServer(t *testing.T, conf httpConfig, ws bool, wsConf wsConfi
 	return srv
 }
 
+func attemptWebsocketConnectionFromOrigin(t *testing.T, srv *httpServer, browserOrigin string) error {
+	t.Helper()
+	dialer := websocket.DefaultDialer
+	_, _, err := dialer.Dial("ws://"+srv.listenAddr(), http.Header{
+		"Content-type":          []string{"application/json"},
+		"Sec-WebSocket-Version": []string{"13"},
+		"Origin":                []string{browserOrigin},
+	})
+	return err
+}
+
 func testRequest(t *testing.T, key, value, host string, srv *httpServer) *http.Response {
 	t.Helper()
 

rpc/websocket.go

@@ -75,14 +75,14 @@ func wsHandshakeValidator(allowedOrigins []string) func(*http.Request) bool {
 			allowAllOrigins = true
 		}
 		if origin != "" {
-			origins.Add(strings.ToLower(origin))
+			origins.Add(origin)
 		}
 	}
 	// allow localhost if no allowedOrigins are specified.
 	if len(origins.ToSlice()) == 0 {
 		origins.Add("http://localhost")
 		if hostname, err := os.Hostname(); err == nil {
-			origins.Add("http://" + strings.ToLower(hostname))
+			origins.Add("http://" + hostname)
 		}
 	}
 	log.Debug(fmt.Sprintf("Allowed origin(s) for WS RPC interface %v", origins.ToSlice()))
@@ -97,7 +97,7 @@ func wsHandshakeValidator(allowedOrigins []string) func(*http.Request) bool {
 		}
 		// Verify origin against whitelist.
 		origin := strings.ToLower(req.Header.Get("Origin"))
-		if allowAllOrigins || origins.Contains(origin) {
+		if allowAllOrigins || originIsAllowed(origins, origin) {
 			return true
 		}
 		log.Warn("Rejected WebSocket connection", "origin", origin)
@@ -120,6 +120,65 @@ func (e wsHandshakeError) Error() string {
 	return s
 }
 
+func originIsAllowed(allowedOrigins mapset.Set, browserOrigin string) bool {
+	it := allowedOrigins.Iterator()
+	for origin := range it.C {
+		if ruleAllowsOrigin(origin.(string), browserOrigin) {
+			return true
+		}
+	}
+	return false
+}
+
+func ruleAllowsOrigin(allowedOrigin string, browserOrigin string) bool {
+	var (
+		allowedScheme, allowedHostname, allowedPort string
+		browserScheme, browserHostname, browserPort string
+		err                                         error
+	)
+	allowedScheme, allowedHostname, allowedPort, err = parseOriginURL(allowedOrigin)
+	if err != nil {
+		log.Warn("Error parsing allowed origin specification", "spec", allowedOrigin, "error", err)
+		return false
+	}
+	browserScheme, browserHostname, browserPort, err = parseOriginURL(browserOrigin)
+	if err != nil {
+		log.Warn("Error parsing browser 'Origin' field", "Origin", browserOrigin, "error", err)
+		return false
+	}
+	if allowedScheme != "" && allowedScheme != browserScheme {
+		return false
+	}
+	if allowedHostname != "" && allowedHostname != browserHostname {
+		return false
+	}
+	if allowedPort != "" && allowedPort != browserPort {
+		return false
+	}
+	return true
+}
+
+func parseOriginURL(origin string) (string, string, string, error) {
+	parsedURL, err := url.Parse(strings.ToLower(origin))
+	if err != nil {
+		return "", "", "", err
+	}
+	var scheme, hostname, port string
+	if strings.Contains(origin, "://") {
+		scheme = parsedURL.Scheme
+		hostname = parsedURL.Hostname()
+		port = parsedURL.Port()
+	} else {
+		scheme = ""
+		hostname = parsedURL.Scheme
+		port = parsedURL.Opaque
+		if hostname == "" {
+			hostname = origin
+		}
+	}
+	return scheme, hostname, port, nil
+}
+
 // DialWebsocketWithDialer creates a new RPC client that communicates with a JSON-RPC server
 // that is listening on the given endpoint using the provided dialer.
 func DialWebsocketWithDialer(ctx context.Context, endpoint, origin string, dialer websocket.Dialer) (*Client, error) {