From 258d01f0d9859caf0a3e8c76f7f3b87de8d40b63 Mon Sep 17 00:00:00 2001
From: zzz <zzz@mail.i2p>
Date: Wed, 20 Aug 2008 14:58:45 +0000
Subject: [PATCH]     * Blocklists: Handle blank lines and \r\n in
 blocklist.txt     * NTCP: Add connection limit, set by
 i2np.ntcp.maxConnections,       default is 500 (very high for now)

---
 history.txt                                   |  5 +++++
 router/java/src/net/i2p/router/Blocklist.java | 10 ++++++++++
 .../src/net/i2p/router/RouterVersion.java     |  2 +-
 .../router/transport/ntcp/EventPumper.java    |  9 +++++++++
 .../router/transport/ntcp/NTCPTransport.java  | 19 +++++++++++++++++++
 5 files changed, 44 insertions(+), 1 deletion(-)

diff --git a/history.txt b/history.txt
index 0e3c8528c..a264fa631 100644
--- a/history.txt
+++ b/history.txt
@@ -1,3 +1,8 @@
+2008-08-20 zzz
+    * Blocklists: Handle blank lines and \r\n in blocklist.txt
+    * NTCP: Add connection limit, set by i2np.ntcp.maxConnections,
+      default is 500 (very high for now)
+
 2008-08-13 zzz
     * i2psnark: Fix OOM vulnerability by checking incoming message length
       (thanks devzero!)
diff --git a/router/java/src/net/i2p/router/Blocklist.java b/router/java/src/net/i2p/router/Blocklist.java
index 73682ec60..9c48acfd0 100644
--- a/router/java/src/net/i2p/router/Blocklist.java
+++ b/router/java/src/net/i2p/router/Blocklist.java
@@ -275,6 +275,14 @@ public class Blocklist {
         byte[] ip2;
         int start1 = 0;
         int end1 = buf.length();
+        if (end1 <= 0)
+            return null;  // blank
+        if (buf.charAt(end1 - 1) == '\r') {  // DataHelper.readLine leaves the \r on there
+            buf.deleteCharAt(end1 - 1);
+            end1--;
+        }
+        if (end1 <= 0)
+            return null;  // blank
         int start2 = -1;
         int mask = -1;
         String comment = null;
@@ -302,6 +310,8 @@ public class Blocklist {
                 mask = index + 1;
             }
         }
+        if (end1 - start1 <= 0)
+            return null;  // blank
         try {
             InetAddress pi = InetAddress.getByName(buf.substring(start1, end1));
             if (pi == null) return null;
diff --git a/router/java/src/net/i2p/router/RouterVersion.java b/router/java/src/net/i2p/router/RouterVersion.java
index 1f9f4170c..79d9109d7 100644
--- a/router/java/src/net/i2p/router/RouterVersion.java
+++ b/router/java/src/net/i2p/router/RouterVersion.java
@@ -17,7 +17,7 @@ import net.i2p.CoreVersion;
 public class RouterVersion {
     public final static String ID = "$Revision: 1.548 $ $Date: 2008-06-07 23:00:00 $";
     public final static String VERSION = "0.6.2";
-    public final static long BUILD = 12;
+    public final static long BUILD = 13;
     public static void main(String args[]) {
         System.out.println("I2P Router version: " + VERSION + "-" + BUILD);
         System.out.println("Router ID: " + RouterVersion.ID);
diff --git a/router/java/src/net/i2p/router/transport/ntcp/EventPumper.java b/router/java/src/net/i2p/router/transport/ntcp/EventPumper.java
index 61ef6df45..3dc9732bc 100644
--- a/router/java/src/net/i2p/router/transport/ntcp/EventPumper.java
+++ b/router/java/src/net/i2p/router/transport/ntcp/EventPumper.java
@@ -383,6 +383,14 @@ public class EventPumper implements Runnable {
         try {
             SocketChannel chan = servChan.accept();
             chan.configureBlocking(false);
+
+            if (!_transport.allowConnection()) {
+                if (_log.shouldLog(Log.WARN))
+                    _log.warn("Receive session request but at connection limit: " + chan.socket().getInetAddress());
+                try { chan.close(); } catch (IOException ioe) { }
+                return;
+            }
+
             if (_context.blocklist().isBlocklisted(chan.socket().getInetAddress().getAddress())) {
                 if (_log.shouldLog(Log.WARN))
                     _log.warn("Receive session request from blocklisted IP: " + chan.socket().getInetAddress());
@@ -391,6 +399,7 @@ public class EventPumper implements Runnable {
                 try { chan.close(); } catch (IOException ioe) { }
                 return;
             }
+
             SelectionKey ckey = chan.register(_selector, SelectionKey.OP_READ);
             NTCPConnection con = new NTCPConnection(_context, _transport, chan, ckey);
             if (_log.shouldLog(Log.DEBUG))
diff --git a/router/java/src/net/i2p/router/transport/ntcp/NTCPTransport.java b/router/java/src/net/i2p/router/transport/ntcp/NTCPTransport.java
index 7c7a8df21..b1798574d 100644
--- a/router/java/src/net/i2p/router/transport/ntcp/NTCPTransport.java
+++ b/router/java/src/net/i2p/router/transport/ntcp/NTCPTransport.java
@@ -286,6 +286,12 @@ public class NTCPTransport extends TransportImpl {
             }
         }
         
+        if (!allowConnection()) {
+            if (_log.shouldLog(Log.WARN))
+                _log.warn("no bid when trying to send to " + toAddress.getIdentity().calculateHash().toBase64() + ", max connection limit reached");
+            return null;
+        }
+
         //if ( (_myAddress != null) && (_myAddress.equals(addr)) ) 
         //    return null; // dont talk to yourself
     
@@ -294,6 +300,19 @@ public class NTCPTransport extends TransportImpl {
         return _slowBid;
     }
     
+    private static final int DEFAULT_MAX_CONNECTIONS = 500;
+    public boolean allowConnection() {
+        int max = DEFAULT_MAX_CONNECTIONS;
+        String mc = _context.getProperty("i2np.ntcp.maxConnections");
+        if (mc != null) {
+            try {
+                  max = Integer.parseInt(mc);
+            } catch (NumberFormatException nfe) {}
+        }
+        return countActivePeers() < max;
+    }
+
+
     void sendComplete(OutNetMessage msg) { _finisher.add(msg); }
     /** async afterSend call, which can take some time w/ jobs, etc */
     private class SendFinisher implements SimpleTimer.TimedEvent {