better protection against fraud peers

git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@3104 6c8d7289-2bf4-0310-a012-ef5d649a1542

source/de/anomic/http/httpd.java

@@ -53,7 +53,6 @@ import java.io.PrintStream;
 import java.lang.reflect.Constructor;
 import java.net.InetAddress;
 import java.net.MalformedURLException;
-import java.net.SocketTimeoutException;
 import java.util.Arrays;
 import java.util.Date;
 import java.util.HashMap;

source/de/anomic/yacy/yacyPeerActions.java

@@ -280,21 +280,30 @@ public class yacyPeerActions {
         if (seed == null) {
             yacyCore.log.logSevere("connect: WRONG seed (NULL)");
             return false;
-        } else if ((error = seed.isProper()) != null) {
+        }
+        if ((error = seed.isProper()) != null) {
             yacyCore.log.logSevere("connect: WRONG seed (" + seed.getName() + "/" + seed.hash + "): " + error);
             return false;
-        } else if ((seedDB.mySeed != null) && (seed.hash.equals(seedDB.mySeed.hash))) {
+        }
+        if ((seedDB.mySeed != null) && (seed.hash.equals(seedDB.mySeed.hash))) {
             yacyCore.log.logInfo("connect: SELF reference " + seed.getAddress());
             return false;
-        } else {
+        }
         String peerType = seed.get(yacySeed.PEERTYPE, yacySeed.PEERTYPE_VIRGIN);
-            // reject unqualified seeds
+        
         if ((peerType.equals(yacySeed.PEERTYPE_VIRGIN)) || (peerType.equals(yacySeed.PEERTYPE_JUNIOR))) {
+            // reject unqualified seeds
             yacyCore.log.logFine("connect: rejecting NOT QUALIFIED " + peerType + " seed " + seed.getName());
             return false;
         }
 
-            // we may store that seed, but still have different cases
+        yacySeed doubleSeed = seedDB.lookupByIP(seed.getInetAddress(), true, false, false);
+        if ((doubleSeed != null) && (doubleSeed.getPort() == seed.getPort()) && (!(doubleSeed.hash.equals(seed.hash)))) {
+            // a user frauds with his peer different peer hashes
+            yacyCore.log.logFine("connect: rejecting FRAUD (double hashes " + doubleSeed.hash + "/" + seed.hash + " on same port " + seed.getPort() + ") peer " + seed.getName());
+            return false;
+        }
+            
             if (seed.get(yacySeed.LASTSEEN, "").length() < 14) {
                 // hack for peers that do not have a LastSeen date
                 seed.put(yacySeed.LASTSEEN, "20040101000000");
@@ -406,7 +415,6 @@ public class yacyPeerActions {
                 }
             }
     }
-    }
 
     private final void disconnectPeer(yacySeed seed) {
         // we do this if we did not get contact with the other peer

source/de/anomic/yacy/yacySeed.java

@@ -63,6 +63,8 @@ import java.io.File;
 import java.io.FileReader;
 import java.io.FileWriter;
 import java.io.IOException;
+import java.net.InetAddress;
+import java.net.UnknownHostException;
 import java.util.Date;
 import java.util.HashMap;
 import java.util.Map;
@@ -344,6 +346,7 @@ public class yacySeed {
     }
 
     public final String getAddress() {
+        // returns an ip:port string
         String ip = (String) this.dna.get(yacySeed.IP);
         if (ip == null) { return null; }
         if (ip.length() < 8) { return null; } // 10.0.0.0
@@ -357,6 +360,33 @@ public class yacySeed {
         return ip + ":" + port;
     }
 
+    public final InetAddress getInetAddress() {
+        // returns the ip address
+        String ip = (String) this.dna.get(yacySeed.IP);
+        if (ip == null) return null;
+        if (ip.length() < 8) return null;
+        String[] ips = ip.split("\\.");
+        if (ips.length != 4) return null;
+        byte[] ipb = new byte[4];
+        ipb[0] = (byte) Integer.parseInt(ips[0]);
+        ipb[1] = (byte) Integer.parseInt(ips[1]);
+        ipb[2] = (byte) Integer.parseInt(ips[2]);
+        ipb[3] = (byte) Integer.parseInt(ips[3]);
+        try {
+            return InetAddress.getByAddress(ipb);
+        } catch (UnknownHostException e) {
+            return null;
+        }
+    }
+    
+    public final int getPort() {
+        final String port = (String) this.dna.get(yacySeed.PORT);
+        if (port == null) return -1;
+        if (port.length() < 2) return -1;
+
+        return Integer.parseInt(port);
+    }
+    
     public final long getUTCDiff() {
         String utc = (String) this.dna.get(yacySeed.UTC);
         if (utc == null) { utc = "+0130"; }

source/de/anomic/yacy/yacySeedDB.java

@@ -526,6 +526,7 @@ public final class yacySeedDB {
             boolean lookupPotential
     ) {
         
+        if (peerIP == null) return null;
         yacySeed seed = null;        
         
         // local peer?