ip-stream - npm Package Compare versions

Comparing version 0.1.0 to 0.2.0

package.json

@@ -11,3 +11,3 @@ {
   ],
-  "version": "0.1.0",
+  "version": "0.2.0",
   "author": "Ben Kelly <[e-mail]>",
@@ -14,0 +14,0 @@ "license": "BSD",

stream.js

@@ -52,2 +52,4 @@ // Copyright (c) 2013, Benjamin J. Kelly ("Author")
 
+  self._fragments = {};
+
   return self;
@@ -71,8 +73,14 @@ }
   try {
-    var iph = new IpHeader(msg.data, msg.offset);
+    msg.ip = new IpHeader(msg.data, msg.offset);
+    msg.offset += msg.ip.length;
 
     // TODO: handle fragmentation
+    if (msg.ip.flags.mf || msg.ip.offset) {
+      msg = this._handleFragment(msg);
+      if (!msg) {
+        callback();
+        return;
+      }
+    }
 
-    msg.ip = iph;
-    msg.offset += iph.length;
     output(msg);
@@ -86,1 +94,49 @@
 }
+
+IpStream.prototype._handleFragment = function(msg) {
+  var key = msg.ip.src + '-' + msg.ip.dst + '-' + msg.ip.id;
+
+  // TODO: cleanup stale fragments to avoid memory leaks
+
+  var list = this._fragments[key];
+  if (!list) {
+    list = this._fragments[key] = [];
+  }
+
+  list.push(msg);
+  list.sort(function(a, b) {
+    return a.ip.offset - b.ip.offset;
+  });
+
+  // If the last packet still expects more fragments, can't reassemble yet.
+  if (list[list.length - 1].ip.flags.mf) {
+    return null;
+  }
+
+  // Ok, last packet is here, do we have the rest?  If there is a gap in
+  // the sequence of bytes, then we can't reassemble yet.
+  var totalLength = 0;
+  var bufferList = [];
+  var expectedOffset = 0;
+  for (var i = 0, n = list.length; i < n; ++i) {
+    var packet = list[i];
+
+    if (packet.ip.offset !== expectedOffset) {
+      return null;
+    }
+
+    totalLength += packet.ip.dataLength;
+    bufferList.push(packet.data.slice(~~packet.offset));
+    expectedOffset += (packet.ip.dataLength / 8);
+  }
+
+  msg.data = Buffer.concat(bufferList, totalLength);
+  msg.ip.dataLength = msg.data.length;
+  msg.ip.totalLength = msg.ip.length + msg.ip.dataLength;
+  msg.ip.flags.mf = false;
+  msg.ip.offset = 0;
+
+  delete this._fragments[key];
+
+  return msg;
+};

No alert changes

Improved metrics

Total package byte prevSize

13600

increased by58.08%

Number of package files

8

increased by14.29%

Lines of code

305

increased by95.51%

No dependency changes