autobahn reject on reserved opcode or bits

Because extensions may use them, we didn't reject on reserved opc or bits set,
just ignored.  But the standard does say we should, so now we do.

Signed-off-by: Andy Green <andy.green@linaro.org>

lib/client-parser.c

@@ -34,8 +34,38 @@ int lws_client_rx_sm(struct lws *wsi, unsigned char c)
 
 		case 13:
 			wsi->u.ws.opcode = c & 0xf;
+			/* revisit if an extension wants them... */
+			switch (wsi->u.ws.opcode) {
+			case 3:
+			case 4:
+			case 5:
+			case 6:
+			case 7:
+			case 0xb:
+			case 0xc:
+			case 0xd:
+			case 0xe:
+			case 0xf:
+				lwsl_info("illegal opcode\n");
+				return -1;
+			default:
+				break;
+			}
 			wsi->u.ws.rsv = (c & 0x70);
+			/* revisit if an extension wants them... */
+			if (
+#ifndef LWS_NO_EXTENSIONS
+				!wsi->count_active_extensions &&
+#endif
+				wsi->u.ws.rsv) {
+				lwsl_info("illegal rsv bits set\n");
+				return -1;
+			}
 			wsi->u.ws.final = !!((c >> 7) & 1);
+			if ((wsi->u.ws.opcode & 8) && !wsi->u.ws.final) {
+				lwsl_info("control message cannot be fragmented\n");
+				return -1;
+			}
 			switch (wsi->u.ws.opcode) {
 			case LWSWSOPC_TEXT_FRAME:
 			case LWSWSOPC_BINARY_FRAME: