Add URL rewriting middleware, and lint out some other middleware.

src/index.js

@@ -106,7 +106,8 @@ let middleware = [
   require("./middleware/core.js"),
   require("./middleware/urlSanitizer.js"),
   require("./middleware/redirects.js"),
-  require("./middleware/webRootPostfixes.js")
+  require("./middleware/webRootPostfixes.js"),
+  require("./middleware/rewriteURL.js")
 ];
 
 function addMiddleware(mw) {

src/middleware/rewriteURL.js

@@ -0,0 +1,184 @@
+const fs = require("fs");
+const url = require("url");
+const createRegex = require("../utils/createRegex.js");
+const ipMatch = require("../utils/ipMatch.js");
+const sanitizeURL = require("../utils/urlSanitizer.js");
+
+module.exports = (req, res, logFacilities, config, next) => {
+  try {
+    decodeURIComponent(req.parsedURL.pathname);
+  } catch (err) {
+    res.error(400);
+  }
+
+  const matchHostname = (hostname) => {
+    if (typeof hostname == "undefined" || hostname == "*") {
+      return true;
+    } else if (
+      req.headers.host &&
+      hostname.indexOf("*.") == 0 &&
+      hostname != "*."
+    ) {
+      const hostnamesRoot = hostname.substring(2);
+      if (
+        req.headers.host == hostnamesRoot ||
+        (req.headers.host.length > hostnamesRoot.length &&
+          req.headers.host.indexOf("." + hostnamesRoot) ==
+            req.headers.host.length - hostnamesRoot.length - 1)
+      ) {
+        return true;
+      }
+    } else if (req.headers.host && req.headers.host == hostname) {
+      return true;
+    }
+    return false;
+  };
+
+  // Handle URL rewriting
+  const rewriteURL = (address, map, callback, _fileState, _mapBegIndex) => {
+    let rewrittenURL = address;
+    let doCallback = true;
+    if (!req.isProxy) {
+      for (let i = _mapBegIndex ? _mapBegIndex : 0; i < map.length; i++) {
+        let mapEntry = map[i];
+        if (
+          req.parsedUrl.pathname != "/" &&
+          (mapEntry.isNotDirectory || mapEntry.isNotFile) &&
+          !_fileState
+        ) {
+          fs.stat(
+            "." + decodeURIComponent(req.parsedUrl.pathname),
+            (err, stats) => {
+              var _fileState = 3;
+              if (err) {
+                _fileState = 3;
+              } else if (stats.isDirectory()) {
+                _fileState = 2;
+              } else if (stats.isFile()) {
+                _fileState = 1;
+              } else {
+                _fileState = 3;
+              }
+              rewriteURL(address, map, callback, _fileState, i);
+            },
+          );
+          doCallback = false;
+          break;
+        }
+        let tempRewrittenURL = rewrittenURL;
+        if (!mapEntry.allowDoubleSlashes) {
+          address = address.replace(/\/+/g, "/");
+          tempRewrittenURL = address;
+        }
+        if (
+          matchHostname(mapEntry.host) &&
+          ipMatch(
+            mapEntry.ip,
+            req.socket ? req.socket.localAddress : undefined,
+          ) &&
+          address.match(createRegex(mapEntry.definingRegex)) &&
+          !(mapEntry.isNotDirectory && _fileState == 2) &&
+          !(mapEntry.isNotFile && _fileState == 1)
+        ) {
+          rewrittenURL = tempRewrittenURL;
+          try {
+            mapEntry.replacements.forEach(function (replacement) {
+              rewrittenURL = rewrittenURL.replace(
+                createRegex(replacement.regex),
+                replacement.replacement,
+              );
+            });
+            if (mapEntry.append) rewrittenURL += mapEntry.append;
+          } catch (err) {
+            doCallback = false;
+            callback(err, null);
+          }
+          break;
+        }
+      }
+    }
+    if (doCallback) callback(null, rewrittenURL);
+  };
+
+  // Rewrite URLs
+  rewriteURL(req.url, config.rewriteMap, function (err, rewrittenURL) {
+    if (err) {
+      res.error(500, err);
+      return;
+    }
+    if (rewrittenURL != req.url) {
+      logFacilities.resmessage(
+        "URL rewritten: " + req.url + " => " + rewrittenURL,
+      );
+      req.url = rewrittenURL;
+      try {
+        req.parsedURL = new URL(
+          req.url,
+          "http" +
+            (req.socket.encrypted ? "s" : "") +
+            "://" +
+            (req.headers.host
+              ? req.headers.host
+              : config.domain
+                ? config.domain
+                : "unknown.invalid"),
+        );
+      } catch (err) {
+        res.error(400, err);
+        return;
+      }
+
+      var sHref = sanitizeURL(
+        req.parsedURL.pathname,
+        config.allowDoubleSlashes,
+      );
+      var preparedReqUrl2 =
+        req.parsedURL.pathname + req.parsedURL.search + req.parsedURL.hash;
+
+      if (
+        req.url != preparedReqUrl2 ||
+        sHref !=
+          req.parsedURL.pathname
+            .replace(/\/\.(?=\/|$)/g, "/")
+            .replace(/\/+/g, "/")
+      ) {
+        res.error(403);
+        logFacilities.errmessage("Content blocked.");
+        return;
+      } else if (sHref != req.parsedURL.pathname) {
+        var rewrittenAgainURL = new url.Url();
+        rewrittenAgainURL.path = null;
+        rewrittenAgainURL.href = null;
+        rewrittenAgainURL.pathname = sHref;
+        rewrittenAgainURL.hostname = null;
+        rewrittenAgainURL.host = null;
+        rewrittenAgainURL.port = null;
+        rewrittenAgainURL.protocol = null;
+        rewrittenAgainURL.slashes = null;
+        rewrittenAgainURL = url.format(rewrittenAgainURL);
+        logFacilities.resmessage(
+          "URL sanitized: " + req.url + " => " + rewrittenAgainURL,
+        );
+        req.url = rewrittenAgainURL;
+        try {
+          req.parsedURL = new URL(
+            req.url,
+            "http" +
+              (req.socket.encrypted ? "s" : "") +
+              "://" +
+              (req.headers.host
+                ? req.headers.host
+                : config.domain
+                  ? config.domain
+                  : "unknown.invalid"),
+          );
+        } catch (err) {
+          res.error(400, err);
+          return;
+        }
+      }
+    }
+
+    next();
+  });
+};

src/middleware/urlSanitizer.js

@@ -2,15 +2,16 @@ const sanitizeURL = require("../utils/urlSanitizer.js");
 const url = require("url");
 
 module.exports = (req, res, logFacilities, config, next) => {
-  let href = req.parsedURL.pathname + req.parsedURL.search;
-
   // Sanitize URL
-  let sanitizedHref = sanitizeURL(href, config.allowDoubleSlashes);
+  let sanitizedHref = sanitizeURL(
+    req.parsedURL.pathname,
+    config.allowDoubleSlashes,
+  );
   let preparedReqUrl =
     req.parsedURL.pathname + req.parsedURL.search + req.parsedURL.hash;
 
   // Check if URL is "dirty"
-  if (href != sanitizedHref && !req.isProxy) {
+  if (req.parsedURL.pathname != sanitizedHref && !req.isProxy) {
     let sanitizedURL = new url.Url();
     sanitizedURL.path = null;
     sanitizedURL.href = null;

src/middleware/webRootPostfixes.js

@@ -95,20 +95,24 @@ module.exports = (req, res, logFacilities, config, next) => {
         return;
       }
 
-      let href = req.parsedURL.pathname + req.parsedURL.search;
-
-      var sHref = sanitizeURL(href, config.allowDoubleSlashes);
+      var sHref = sanitizeURL(
+        req.parsedURL.pathname,
+        config.allowDoubleSlashes,
+      );
       var preparedReqUrl2 =
         req.parsedURL.pathname + req.parsedURL.search + req.parsedURL.hash;
 
       if (
         req.url != preparedReqUrl2 ||
-        sHref != href.replace(/\/\.(?=\/|$)/g, "/").replace(/\/+/g, "/")
+        sHref !=
+          req.parsedURL.pathname
+            .replace(/\/\.(?=\/|$)/g, "/")
+            .replace(/\/+/g, "/")
       ) {
         res.error(403);
         logFacilities.errmessage("Content blocked.");
         return;
-      } else if (sHref != href) {
+      } else if (sHref != req.parsedURL.pathname) {
         var rewrittenAgainURL = new url.Url();
         rewrittenAgainURL.path = null;
         rewrittenAgainURL.href = null;