Router: Add IPv6 analysis to Sybil checker

Add to console sybil page
Fix links for IPs close to us
Header and reason tweaks
Increase verified family credit

apps/routerconsole/java/src/net/i2p/router/web/helpers/SybilRenderer.java

@@ -134,8 +134,8 @@ public class SybilRenderer {
         Hash us = _context.routerHash();
         Analysis analysis = Analysis.getInstance(_context);
         List<RouterInfo> ris = null;
-        if (mode != 0 && mode < 12) {
+        if (mode != 0 && (mode < 12 || mode == 17 || mode == 18)) {
-            if (mode >= 2 && mode <= 6) {
+            if (mode >= 2 && (mode <= 6 || mode == 17 || mode == 18)) {
                 // review all routers for family and IP analysis
                 ris = analysis.getAllRouters(us);
             } else {
@@ -159,8 +159,10 @@ public class SybilRenderer {
                    "</li><li><a href=\"netdb?f=3&amp;m=2\">Same Family</a>" +
                    "</li><li><a href=\"netdb?f=3&amp;m=3\">IP close to us</a>" +
                    "</li><li><a href=\"netdb?f=3&amp;m=4\">Same IP</a>" +
-                   "</li><li><a href=\"netdb?f=3&amp;m=5\">Same /24</a>" +
+                   "</li><li><a href=\"netdb?f=3&amp;m=5\">Same IPv4 /24</a>" +
-                   "</li><li><a href=\"netdb?f=3&amp;m=6\">Same /16</a>" +
+                   "</li><li><a href=\"netdb?f=3&amp;m=6\">Same IPv4 /16</a>" +
+                   "</li><li><a href=\"netdb?f=3&amp;m=17\">Same IPv6 /64</a>" +
+                   "</li><li><a href=\"netdb?f=3&amp;m=18\">Same IPv6 /48</a>" +
                    "</li><li><a href=\"netdb?f=3&amp;m=7\">Pair distance</a>" +
                    "</li><li><a href=\"netdb?f=3&amp;m=8\">Close to us</a>" +
                    "</li><li><a href=\"netdb?f=3&amp;m=9\">Close to us tomorrow</a>" +
@@ -189,6 +191,10 @@ public class SybilRenderer {
             renderIP24Summary(out, buf, analysis, ris, points);
         } else if (mode == 6) {
             renderIP16Summary(out, buf, analysis, ris, points);
+        } else if (mode == 17) {
+            renderIP64Summary(out, buf, analysis, ris, points);
+        } else if (mode == 18) {
+            renderIP48Summary(out, buf, analysis, ris, points);
         } else if (mode == 7) {
             renderPairSummary(out, buf, analysis, ris, points);
         } else if (mode == 8) {
@@ -385,8 +391,10 @@ public class SybilRenderer {
         List<RouterInfo> ri32 = new ArrayList<RouterInfo>(4);
         List<RouterInfo> ri24 = new ArrayList<RouterInfo>(4);
         List<RouterInfo> ri16 = new ArrayList<RouterInfo>(4);
-        analysis.calculateIPGroupsUs(ris, points, ri32, ri24, ri16);
+        List<RouterInfo> ri64 = new ArrayList<RouterInfo>(4);
-        renderIPGroupsUs(out, buf, ri32, ri24, ri16);
+        List<RouterInfo> ri48 = new ArrayList<RouterInfo>(4);
+        analysis.calculateIPGroupsUs(ris, points, ri32, ri24, ri16, ri64, ri48);
+        renderIPGroupsUs(out, buf, ri32, ri24, ri16, ri64, ri48);
     }
 
     /**
@@ -413,6 +421,22 @@ public class SybilRenderer {
         renderIPGroups16(out, buf, map);
     }
 
+    /**
+     *  @since 0.9.57
+     */
+    private void renderIP64Summary(Writer out, StringBuilder buf, Analysis analysis, List<RouterInfo> ris, Map<Hash, Points> points) throws IOException {
+        Map<Long, List<RouterInfo>> map = analysis.calculateIPGroups64(ris, points);
+        renderIPGroups64(out, buf, map);
+    }
+
+    /**
+     *  @since 0.9.57
+     */
+    private void renderIP48Summary(Writer out, StringBuilder buf, Analysis analysis, List<RouterInfo> ris, Map<Hash, Points> points) throws IOException {
+        Map<Long, List<RouterInfo>> map = analysis.calculateIPGroups48(ris, points);
+        renderIPGroups48(out, buf, map);
+    }
+
     /**
      *  @since 0.9.38 split out from renderRouterInfoHTML()
      */
@@ -565,16 +589,17 @@ public class SybilRenderer {
         writeBuf(out, buf);
     }
 
-    private static class FooComparator implements Comparator<Integer>, Serializable {
+    private static class FooComparator<K extends Comparable> implements Comparator<K>, Serializable {
-         private final Map<Integer, List<RouterInfo>> _o;
+         private final Map<K, List<RouterInfo>> _o;
-         public FooComparator(Map<Integer, List<RouterInfo>> o) { _o = o;}
+         public FooComparator(Map<K, List<RouterInfo>> o) { _o = o;}
-         public int compare(Integer l, Integer r) {
+         @SuppressWarnings("unchecked")
+         public int compare(K l, K r) {
              // reverse by count
              int rv = _o.get(r).size() - _o.get(l).size();
              if (rv != 0)
                  return rv;
-             // foward by IP
+             // forward by IP
-             return l.intValue() - r.intValue();
+             return l.compareTo(r);
         }
     }
 
@@ -587,7 +612,7 @@ public class SybilRenderer {
              int rv = _o.get(r).size() - _o.get(l).size();
              if (rv != 0)
                  return rv;
-             // foward by name
+             // forward by name
              return _comp.compare(l, r);
         }
     }
@@ -596,7 +621,8 @@ public class SybilRenderer {
      *
      */
     private void renderIPGroupsUs(Writer out, StringBuilder buf, List<RouterInfo> ri32,
-                                  List<RouterInfo> ri24, List<RouterInfo> ri16) throws IOException {
+                                  List<RouterInfo> ri24, List<RouterInfo> ri16,
+                                  List<RouterInfo> ri64, List<RouterInfo> ri48) throws IOException {
         buf.append("<h3 id=\"ourIP\" class=\"sybils\">Routers close to Our IP</h3>");
         boolean found = false;
         for (RouterInfo info : ri32) {
@@ -608,14 +634,28 @@ public class SybilRenderer {
         }
         for (RouterInfo info : ri24) {
              buf.append("<p id=\"sybil_info\"><b>");
-             buf.append("Same /24 as us");
+             buf.append("Same IPv4 /24 as us");
              buf.append(":</b></p>");
              renderRouterInfo(buf, info, null, false, false);
              found = true;
         }
         for (RouterInfo info : ri16) {
              buf.append("<p id=\"sybil_info\"><b>");
-             buf.append("Same /16 as us");
+             buf.append("Same IPv4 /16 as us");
+             buf.append(":</b></p>");
+             renderRouterInfo(buf, info, null, false, false);
+             found = true;
+        }
+        for (RouterInfo info : ri64) {
+             buf.append("<p id=\"sybil_info\"><b>");
+             buf.append("Same IPv6 /64 as us");
+             buf.append(":</b></p>");
+             renderRouterInfo(buf, info, null, false, false);
+             found = true;
+        }
+        for (RouterInfo info : ri48) {
+             buf.append("<p id=\"sybil_info\"><b>");
+             buf.append("Same IPv6 /48 as us");
              buf.append(":</b></p>");
              renderRouterInfo(buf, info, null, false, false);
              found = true;
@@ -629,9 +669,9 @@ public class SybilRenderer {
      *
      */
     private void renderIPGroups32(Writer out, StringBuilder buf, Map<Integer, List<RouterInfo>> map) throws IOException {
-        buf.append("<h3 id=\"sameIP\" class=\"sybils\">Routers with the Same IP</h3>");
+        buf.append("<h3 id=\"sameIP\" class=\"sybils\">Routers with the same IPv4</h3>");
         List<Integer> foo = new ArrayList<Integer>(map.keySet());
-        Collections.sort(foo, new FooComparator(map));
+        Collections.sort(foo, new FooComparator<Integer>(map));
         boolean found = false;
         for (Integer ii : foo) {
             List<RouterInfo> ris = map.get(ii);
@@ -659,9 +699,9 @@ public class SybilRenderer {
      *
      */
     private void renderIPGroups24(Writer out, StringBuilder buf, Map<Integer, List<RouterInfo>> map) throws IOException {
-        buf.append("<h3 id=\"same24\" class=\"sybils\">Routers in the Same /24 (2 minimum)</h3>");
+        buf.append("<h3 id=\"same24\" class=\"sybils\">Routers in the same IPv4 /24</h3>");
         List<Integer> foo = new ArrayList<Integer>(map.keySet());
-        Collections.sort(foo, new FooComparator(map));
+        Collections.sort(foo, new FooComparator<Integer>(map));
         boolean found = false;
         for (Integer ii : foo) {
             List<RouterInfo> ris = map.get(ii);
@@ -688,9 +728,9 @@ public class SybilRenderer {
      *
      */
     private void renderIPGroups16(Writer out, StringBuilder buf, Map<Integer, List<RouterInfo>> map) throws IOException {
-        buf.append("<h3 id=\"same16\" class=\"sybils\">Routers in the Same /16 (4 minimum)</h3>");
+        buf.append("<h3 id=\"same16\" class=\"sybils\">Routers in the same IPv4 /16 (4 minimum)</h3>");
         List<Integer> foo = new ArrayList<Integer>(map.keySet());
-        Collections.sort(foo, new FooComparator(map));
+        Collections.sort(foo, new FooComparator<Integer>(map));
         boolean found = false;
         for (Integer ii : foo) {
             List<RouterInfo> ris = map.get(ii);
@@ -712,6 +752,67 @@ public class SybilRenderer {
         writeBuf(out, buf);
     }
 
+    /**
+     * @since 0.9.57
+     */
+    private void renderIPGroups64(Writer out, StringBuilder buf, Map<Long, List<RouterInfo>> map) throws IOException {
+        buf.append("<h3 id=\"same64\" class=\"sybils\">Routers in the same IPv6 /64</h3>");
+        List<Long> foo = new ArrayList<Long>(map.keySet());
+        Collections.sort(foo, new FooComparator<Long>(map));
+        boolean found = false;
+        for (Long ii : foo) {
+            List<RouterInfo> ris = map.get(ii);
+            int count = ris.size();
+            long i = ii.longValue();
+            int i0 = (int) ((i >> 48) & 0xffff);
+            int i2 = (int) ((i >> 32) & 0xffff);
+            int i4 = (int) ((i >> 16) & 0xffff);
+            int i6 = (int) (i & 0xffff);
+            String sip = Integer.toString(i0, 16) + ":" + Integer.toString(i2, 16) + ':' +
+                         Integer.toString(i4, 16) + ':' + Integer.toString(i6, 16) + "::";
+            buf.append("<p class=\"sybil_info\"><b>").append(count).append(" routers with IP <a href=\"/netdb?ip=")
+               .append(sip).append("&amp;sybil\">").append(sip)
+               .append("</a></b></p>");
+            for (RouterInfo info : ris) {
+                found = true;
+                renderRouterInfo(buf, info, null, false, false);
+            }
+        }
+        if (!found)
+            buf.append("<p class=\"notfound\">None</p>");
+        writeBuf(out, buf);
+    }
+
+    /**
+     * @since 0.9.57
+     */
+    private void renderIPGroups48(Writer out, StringBuilder buf, Map<Long, List<RouterInfo>> map) throws IOException {
+        buf.append("<h3 id=\"same48\" class=\"sybils\">Routers in the same IPv6 /48 (4 minimum)</h3>");
+        List<Long> foo = new ArrayList<Long>(map.keySet());
+        Collections.sort(foo, new FooComparator<Long>(map));
+        boolean found = false;
+        for (Long ii : foo) {
+            List<RouterInfo> ris = map.get(ii);
+            int count = ris.size();
+            long i = ii.longValue();
+            int i0 = (int) ((i >> 32) & 0xffff);
+            int i2 = (int) ((i >> 16) & 0xffff);
+            int i4 = (int) (i & 0xffff);
+            String sip = Integer.toString(i0, 16) + ":" + Integer.toString(i2, 16) + ':' +
+                         Integer.toString(i4, 16) + "::";
+            buf.append("<p class=\"sybil_info\"><b>").append(count).append(" routers with IP <a href=\"/netdb?ip=")
+               .append(sip).append("&amp;sybil\">").append(sip)
+               .append("</a></b></p>");
+            for (RouterInfo info : ris) {
+                found = true;
+                renderRouterInfo(buf, info, null, false, false);
+            }
+        }
+        if (!found)
+            buf.append("<p class=\"notfound\">None</p>");
+        writeBuf(out, buf);
+    }
+
     /**
      *
      */

router/java/src/net/i2p/router/sybil/Analysis.java

@@ -85,8 +85,15 @@ public class Analysis extends JobImpl implements RouterApp {
     private static final double POINTS_US32 = 25.0;
     private static final double POINTS_US24 = 20.0;
     private static final double POINTS_US16 = 10.0;
+
+    // IPv6 since 0.9.57, likely to be on top of IPv4, so make lower
+    private static final double POINTS_V6_US64 = 12.5;
+    private static final double POINTS_V6_US48 = 5.0;
+    private static final double POINTS64 = 2.0;
+    private static final double POINTS48 = 0.5;
+
     private static final double POINTS_FAMILY = -10.0;
-    private static final double POINTS_FAMILY_VERIFIED = POINTS_FAMILY * 2;
+    private static final double POINTS_FAMILY_VERIFIED = POINTS_FAMILY * 4;
     private static final double POINTS_NONFF = -5.0;
     private static final double POINTS_BAD_FAMILY = 20.0;
     private static final double POINTS_BAD_OUR_FAMILY = 100.0;
@@ -374,13 +381,14 @@ public class Analysis extends JobImpl implements RouterApp {
 
         // IP analysis
         calculateIPGroupsFamily(ris, points);
-        List<RouterInfo> ri32 = new ArrayList<RouterInfo>(4);
+        // unused here, just for the console, so use the same for all of them
-        List<RouterInfo> ri24 = new ArrayList<RouterInfo>(4);
+        List<RouterInfo> dummy = new DummyList();
-        List<RouterInfo> ri16 = new ArrayList<RouterInfo>(4);
+        calculateIPGroupsUs(ris, points, dummy, dummy, dummy, dummy, dummy);
-        calculateIPGroupsUs(ris, points, ri32, ri24, ri16);
         calculateIPGroups32(ris, points);
         calculateIPGroups24(ris, points);
         calculateIPGroups16(ris, points);
+        calculateIPGroups64(ris, points);
+        calculateIPGroups48(ris, points);
 
         // Pairwise distance analysis
         List<Pair> pairs = new ArrayList<Pair>(PAIRMAX);
@@ -427,6 +435,15 @@ public class Analysis extends JobImpl implements RouterApp {
         return points;
     }
 
+    /**
+     *  @since 0.9.57
+     */
+    private static class DummyList extends ArrayList<RouterInfo> {
+        public DummyList() { super(0); }
+        @Override
+        public boolean add(RouterInfo ri) { return true; }
+    }
+
     /**
      *  Blocklist and Banlist if configured
      *  @since 0.9.41
@@ -545,46 +562,118 @@ public class Analysis extends JobImpl implements RouterApp {
         return null;
     }
 
+    /**
+     * v6 only
+     * @since 0.9.57
+     */
+    private static byte[] getIPv6(RouterInfo ri) {
+        for (RouterAddress ra : ri.getAddresses()) {
+            byte[] rv = ra.getIP();
+            if (rv != null && rv.length == 16)
+                return rv;
+        }
+        return null;
+    }
+
     /**
      *  @param ri32 out parameter
      *  @param ri24 out parameter
      *  @param ri16 out parameter
+     *  @param ri64 out parameter
+     *  @param ri48 out parameter
      *  @since 0.9.38 split out from renderIPGroupsUs()
      */
     public void calculateIPGroupsUs(List<RouterInfo> ris, Map<Hash, Points> points,
-                                    List<RouterInfo> ri32, List<RouterInfo> ri24, List<RouterInfo> ri16) {
+                                    List<RouterInfo> ri32, List<RouterInfo> ri24, List<RouterInfo> ri16,
+                                    List<RouterInfo> ri64, List<RouterInfo> ri48) {
         RouterInfo us = _context.router().getRouterInfo();
         byte[] ourIP = getIP(us);
         if (ourIP == null) {
             String last = _context.getProperty("i2np.lastIP");
-            if (last == null)
+            if (last != null)
-                return;
+                ourIP = Addresses.getIPOnly(last);
-            ourIP = Addresses.getIPOnly(last);
+        }
-            if (ourIP == null)
+        byte[] ourIPv6 = getIPv6(us);
-                return;
+        if (ourIPv6 == null) {
+            String last = _context.getProperty("i2np.lastIPv6");
+            if (last != null)
+                ourIPv6 = Addresses.getIPOnly(last);
+        }
+        if (ourIP == null && ourIPv6 == null)
+            return;
+
+        String reason32;
+        String reason24;
+        String reason16;
+        String reason64;
+        String reason48;
+
+        if (ourIP != null) {
+            reason32 = "Same IP as <a href=\"/netdb?ip=" +
+                       Addresses.toString(ourIP) +
+                       "&amp;sybil\">us</a>";
+            reason24 = "Same IPv4 /24 as <a href=\"/netdb?ip=" +
+                       (ourIP[0] & 0xff) + '.' +
+                       (ourIP[1] & 0xff) + '.' +
+                       (ourIP[2] & 0xff) +
+                       ".0/24&amp;sybil\">us</a>";
+            reason16 = "Same IPv4 /16 as <a href=\"/netdb?ip=" +
+                       (ourIP[0] & 0xff) + '.' +
+                       (ourIP[1] & 0xff) +
+                       ".0.0/16&amp;sybil\">us</a>";
+        } else {
+            reason32 = null;
+            reason24 = null;
+            reason16 = null;
+        }
+        if (ourIPv6 != null) {
+            reason64 = "Same IPv6 /64 as <a href=\"/netdb?ip=" +
+                        Integer.toString(((ourIPv6[0] << 8) & 0xff00) | (ourIPv6[1] & 0xff), 16) + ':' +
+                        Integer.toString(((ourIPv6[2] << 8) & 0xff00) | (ourIPv6[3] & 0xff), 16) + ':' +
+                        Integer.toString(((ourIPv6[4] << 8) & 0xff00) | (ourIPv6[5] & 0xff), 16) + ':' +
+                        Integer.toString(((ourIPv6[6] << 8) & 0xff00) | (ourIPv6[7] & 0xff), 16) +
+                        "::&amp;sybil\">us</a>";
+            reason48 = "Same IPv6 /48 as <a href=\"/netdb?ip=" +
+                        Integer.toString(((ourIPv6[0] << 8) & 0xff00) | (ourIPv6[1] & 0xff), 16) + ':' +
+                        Integer.toString(((ourIPv6[2] << 8) & 0xff00) | (ourIPv6[3] & 0xff), 16) + ':' +
+                        Integer.toString(((ourIPv6[4] << 8) & 0xff00) | (ourIPv6[5] & 0xff), 16) +
+                        "::&amp;sybil\">us</a>";
+        } else {
+            reason64 = null;
+            reason48 = null;
         }
-        String reason32 = "Same IP as <a href=\"/netdb?ip=" +
-                          ourIP[0] + '.' + ourIP[1] + '.' + ourIP[2] + '.' + ourIP[3] + "&amp;sybil\">us</a>";
-        String reason24 = "Same /24 IP as <a href=\"/netdb?ip=" +
-                          ourIP[0] + '.' + ourIP[1] + '.' + ourIP[2] + ".0/24&amp;sybil\">us</a>";
-        String reason16 = "Same /16 IP as <a href=\"/netdb?ip=" +
-                          ourIP[0] + '.' + ourIP[1] + ".0.0/16&amp;sybil\">us</a>";
         for (RouterInfo info : ris) {
-            byte[] ip = getIP(info);
+            if (ourIP != null) {
-            if (ip == null)
+                byte[] ip = getIP(info);
-                continue;
+                if (ip == null)
-            if (ip[0] == ourIP[0] && ip[1] == ourIP[1]) {
+                    continue;
-                if (ip[2] == ourIP[2]) {
+                if (ip[0] == ourIP[0] && ip[1] == ourIP[1]) {
-                    if (ip[3] == ourIP[3]) {
+                    if (ip[2] == ourIP[2]) {
-                        addPoints(points, info.getHash(), POINTS_US32, reason32);
+                        if (ip[3] == ourIP[3]) {
-                        ri32.add(info);
+                            addPoints(points, info.getHash(), POINTS_US32, reason32);
+                            ri32.add(info);
+                        } else {
+                            addPoints(points, info.getHash(), POINTS_US24, reason24);
+                            ri24.add(info);
+                        }
                     } else {
-                        addPoints(points, info.getHash(), POINTS_US24, reason24);
+                        addPoints(points, info.getHash(), POINTS_US16, reason16);
-                        ri24.add(info);
+                        ri16.add(info);
+                    }
+                }
+            }
+            if (ourIPv6 != null) {
+                byte[] ip = getIPv6(info);
+                if (ip == null)
+                    continue;
+                if (DataHelper.eq(ip, 0, ourIPv6, 0, 6)) {
+                    if (ip[6] == ourIPv6[6] && ip[7] == ourIPv6[7]) {
+                        addPoints(points, info.getHash(), POINTS_V6_US64, reason64);
+                        ri64.add(info);
+                    } else {
+                        addPoints(points, info.getHash(), POINTS_V6_US48, reason48);
+                        ri48.add(info);
                     }
-                } else {
-                    addPoints(points, info.getHash(), POINTS_US16, reason16);
-                    ri16.add(info);
                 }
             }
         }
@@ -666,7 +755,7 @@ public class Analysis extends JobImpl implements RouterApp {
             int i0 = i >> 16;
             int i1 = (i >> 8) & 0xff;
             int i2 = i & 0xff;
-            String reason = "Same /24 IP with <a href=\"/netdb?ip=" +
+            String reason = "Same IPv4 /24 with <a href=\"/netdb?ip=" +
                             i0 + '.' + i1 + '.' + i2 + ".0/24&amp;sybil\">" +
                             (count - 1) + " other" + (( count > 2) ? "s" : "") + "</a>";
             for (RouterInfo info : ris) {
@@ -717,7 +806,7 @@ public class Analysis extends JobImpl implements RouterApp {
             int i = ii.intValue();
             int i0 = i >> 8;
             int i1 = i & 0xff;
-            String reason = "Same /16 IP with <a href=\"/netdb?ip=" +
+            String reason = "Same IPv4 /16 with <a href=\"/netdb?ip=" +
                             i0 + '.' + i1 + ".0.0/16&amp;sybil\">" +
                             (count - 1) + " other" + (( count > 2) ? "s" : "") + "</a>";
             for (RouterInfo info : ris) {
@@ -735,6 +824,129 @@ public class Analysis extends JobImpl implements RouterApp {
         return rv;
     }
 
+    /**
+     *  @since 0.9.57
+     */
+    public Map<Long, List<RouterInfo>> calculateIPGroups64(List<RouterInfo> ris, Map<Hash, Points> points) {
+        ObjectCounter<Long> oc = new ObjectCounter<Long>();
+        for (RouterInfo info : ris) {
+            byte[] ip = getIPv6(info);
+            if (ip == null)
+                continue;
+            Long x = Long.valueOf(DataHelper.fromLong8(ip, 0));
+            oc.increment(x);
+        }
+        Map<Long, List<RouterInfo>> rv = new HashMap<Long, List<RouterInfo>>();
+        for (Long ii : oc.objects()) {
+            int count = oc.count(ii);
+            if (count >= 2)
+                rv.put(ii, new ArrayList<RouterInfo>(count));
+        }
+        for (Map.Entry<Long, List<RouterInfo>> e : rv.entrySet()) {
+            Long ii = e.getKey();
+            int count = oc.count(ii);
+            double point = POINTS64 * (count - 1);
+            long i = ii.longValue();
+            int i0 = (int) ((i >> 56) & 0xff);
+            int i1 = (int) ((i >> 48) & 0xff);
+            int i2 = (int) ((i >> 40) & 0xff);
+            int i3 = (int) ((i >> 32) & 0xff);
+            int i4 = (int) ((i >> 24) & 0xff);
+            int i5 = (int) ((i >> 16) & 0xff);
+            int i6 = (int) ((i >> 8) & 0xff);
+            int i7 = (int) (i & 0xff);
+            String reason = "Same IPv6 /64 with <a href=\"/netdb?ip=" +
+                            Integer.toString((i0 << 8) | i1, 16) + ':' +
+                            Integer.toString((i2 << 8) | i3, 16) + ':' +
+                            Integer.toString((i4 << 8) | i5, 16) + ':' +
+                            Integer.toString((i6 << 8) | i7, 16) +
+                            "::&amp;sybil\">" +
+                            (count - 1) + " other" + (( count > 2) ? "s" : "") + "</a>";
+            for (RouterInfo info : ris) {
+                byte[] ip = getIPv6(info);
+                if (ip == null)
+                    continue;
+                if ((ip[0] & 0xff) != i0)
+                    continue;
+                if ((ip[1] & 0xff) != i1)
+                    continue;
+                if ((ip[2] & 0xff) != i2)
+                    continue;
+                if ((ip[3] & 0xff) != i3)
+                    continue;
+                if ((ip[4] & 0xff) != i4)
+                    continue;
+                if ((ip[5] & 0xff) != i5)
+                    continue;
+                if ((ip[6] & 0xff) != i6)
+                    continue;
+                if ((ip[7] & 0xff) != i7)
+                    continue;
+                e.getValue().add(info);
+                addPoints(points, info.getHash(), point, reason);
+            }
+        }
+        return rv;
+    }
+
+    /**
+     *  @since 0.9.57
+     */
+    public Map<Long, List<RouterInfo>> calculateIPGroups48(List<RouterInfo> ris, Map<Hash, Points> points) {
+        ObjectCounter<Long> oc = new ObjectCounter<Long>();
+        for (RouterInfo info : ris) {
+            byte[] ip = getIPv6(info);
+            if (ip == null)
+                continue;
+            Long x = Long.valueOf(DataHelper.fromLong(ip, 0, 6));
+            oc.increment(x);
+        }
+        Map<Long, List<RouterInfo>> rv = new HashMap<Long, List<RouterInfo>>();
+        for (Long ii : oc.objects()) {
+            int count = oc.count(ii);
+            if (count >= 4)
+                rv.put(ii, new ArrayList<RouterInfo>(count));
+        }
+        for (Map.Entry<Long, List<RouterInfo>> e : rv.entrySet()) {
+            Long ii = e.getKey();
+            int count = oc.count(ii);
+            double point = POINTS48 * (count - 1);
+            long i = ii.longValue();
+            int i0 = (int) ((i >> 40) & 0xff);
+            int i1 = (int) ((i >> 32) & 0xff);
+            int i2 = (int) ((i >> 24) & 0xff);
+            int i3 = (int) ((i >> 16) & 0xff);
+            int i4 = (int) ((i >> 8) & 0xff);
+            int i5 = (int) (i & 0xff);
+            String reason = "Same IPv6 /48 with <a href=\"/netdb?ip=" +
+                            Integer.toString((i0 << 8) | i1, 16) + ':' +
+                            Integer.toString((i2 << 8) | i3, 16) + ':' +
+                            Integer.toString((i4 << 8) | i5, 16) +
+                            "::&amp;sybil\">" +
+                            (count - 1) + " other" + (( count > 2) ? "s" : "") + "</a>";
+            for (RouterInfo info : ris) {
+                byte[] ip = getIPv6(info);
+                if (ip == null)
+                    continue;
+                if ((ip[0] & 0xff) != i0)
+                    continue;
+                if ((ip[1] & 0xff) != i1)
+                    continue;
+                if ((ip[2] & 0xff) != i2)
+                    continue;
+                if ((ip[3] & 0xff) != i3)
+                    continue;
+                if ((ip[4] & 0xff) != i4)
+                    continue;
+                if ((ip[5] & 0xff) != i5)
+                    continue;
+                e.getValue().add(info);
+                addPoints(points, info.getHash(), point, reason);
+            }
+        }
+        return rv;
+    }
+
     /**
      *  @return map of family name to list of routers in that family
      *  @since 0.9.38 split out from renderIPGroupsFamily()