netsec-ethz · tzaeschke · May 4, 2026 · May 4, 2026
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -9,6 +9,9 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 
 - Update to JPAN 0.7.0 and improve SCMP error handling.
   [#18](https://github.com/netsec-ethz/jpan-cli/pull/18)
+- Adapt to JPAN 0.7.0 and improve SCMP error handling.
+  [#14](https://github.com/netsec-ethz/jpan-cli/pull/14)
+  [#19](https://github.com/netsec-ethz/jpan-cli/pull/19)
 
 ## [0.2.2] - 2026-03-27
 

diff --git a/src/main/java/org/scion/cli/Cli.java b/src/main/java/org/scion/cli/Cli.java
@@ -26,7 +26,7 @@
 
 public class Cli {
 
-  private static final String VERSION = "0.2.2 (using JPAN 0.6.1)";
+  private static final String VERSION = "0.3.0-SNAPSHOT (using JPAN 0.7.0)";
 
   public static void main(String... args) {
     System.setProperty(org.slf4j.simple.SimpleLogger.DEFAULT_LOG_LEVEL_KEY, "ERROR");

diff --git a/src/main/java/org/scion/cli/Ping.java b/src/main/java/org/scion/cli/Ping.java
@@ -20,7 +20,6 @@
 import java.net.*;
 import java.nio.ByteBuffer;
 import java.util.*;
-import java.util.concurrent.atomic.AtomicBoolean;
 import org.scion.cli.util.Errors;
 import org.scion.cli.util.ExitCodeException;
 import org.scion.cli.util.Prober;
@@ -72,7 +71,7 @@ public void run(String... args) throws IOException {
                 dstAddress.getIsdAs(), dstAddress.getInetAddress(), Constants.SCMP_PORT);
       }
       if (paths.isEmpty()) {
-        String src = ScionUtil.toStringIA(service.getLocalIsdAs());
+        String src = localIsdAses(service);
         String dst = ScionUtil.toStringIA(dstAddress.getIsdAs());
         throw new ExitCodeException(2, "No path found from " + src + " to " + dst);
       }
@@ -158,7 +157,7 @@ private void run(List<Path> paths) throws IOException {
         }
       }
       if (newPaths.isEmpty()) {
-        String src = ScionUtil.toStringIA(Scion.defaultService().getLocalIsdAs());
+        String src = localIsdAses(Scion.defaultService());
         String dst = ScionUtil.toStringIA(dstAddress.getIsdAs());
         throw new ExitCodeException(2, "No path found from " + src + " to " + dst);
       }
@@ -167,6 +166,10 @@ private void run(List<Path> paths) throws IOException {
       path = paths.get(0);
     }
 
+    send(path);
+  }
+
+  private void send(Path path) throws IOException {
     ByteBuffer data = ByteBuffer.allocate(payloadSize);
     for (int i = 0; i < payloadSize; i++) {
       data.put((byte) i);
@@ -184,22 +187,19 @@ private void run(List<Path> paths) throws IOException {
     if (localPort != null) {
       builder.setLocalPort(localPort);
     }
-    // No concurrency, but must be final
-    AtomicBoolean scmpError = new AtomicBoolean(false);
     try (ScmpSender sender = builder.build()) {
       sender.setTimeOut(timeoutMs);
-      sender.setScmpErrorListener(
+      sender.setScmpErrorHandler(
           e -> {
             println("SCMP Error: " + e.getTypeCode().getText());
-            scmpError.set(true);
+            return false;
           });
       println("Listening on port " + sender.getLocalAddress().getPort() + " ...");
       println("Resolved local address: ");
       println("  " + localAddress);
       printPath(path);
 
       for (int i = 0; i < count; i++) {
-        // TODO this may throw an IOException if external interface is down
         try {
           Scmp.EchoMessage msg = sender.sendEchoRequest(path, data);
           if (i == 0) {
@@ -220,11 +220,7 @@ private void run(List<Path> paths) throws IOException {
             Util.sleep(intervalMs);
           }
         } catch (IOException e) {
-          if (scmpError.getAndSet(false)) {
-            // Ignore, we already reported the error
-            continue;
-          }
-          throw e;
+          println("Error: " + e.getMessage());
         }
       }
     }
@@ -241,7 +237,7 @@ private static void printPath(Path path) {
     String nl = System.lineSeparator();
     String sb = "Using path:" + nl + "  Hops: " + ScionUtil.toStringPath(path.getMetadata());
     sb += " MTU: " + path.getMetadata().getMtu();
-    sb += " NextHop: " + path.getMetadata().getInterface().getAddress() + nl;
+    sb += " NextHop: " + path.getMetadata().getLocalInterface().getAddress() + nl;
     println(sb);
   }
 

diff --git a/src/main/java/org/scion/cli/Showpaths.java b/src/main/java/org/scion/cli/Showpaths.java
@@ -135,7 +135,7 @@ public void run() throws IOException {
         new InetSocketAddress(InetAddress.getLoopbackAddress(), 12345);
     List<Path> paths = service.getPaths(isdAs, destinationAddress);
     if (paths.isEmpty()) {
-      String src = ScionUtil.toStringIA(service.getLocalIsdAs());
+      String src = localIsdAses(service);
       String dst = ScionUtil.toStringIA(isdAs);
       throw new ExitCodeException(1, "No path found from " + src + " to " + dst);
     }
@@ -217,7 +217,7 @@ private static String toStringExpiry(PathMetadata meta) {
   private static String toStringLatency(PathMetadata meta) {
     int latencyMs = 0;
     boolean latencyComplete = true;
-    for (int l : meta.getLatencyList()) {
+    for (int l : meta.getLatencies()) {
       if (l >= 0) {
         latencyMs += l;
       } else {
@@ -234,7 +234,7 @@ private static String toStringLatency(PathMetadata meta) {
   private static String toStringBandwidth(PathMetadata meta) {
     long bw = Long.MAX_VALUE;
     boolean bwComplete = true;
-    for (long l : meta.getBandwidthList()) {
+    for (long l : meta.getBandwidths()) {
       if (l > 0) {
         bw = Math.min(bw, l);
       } else {
@@ -251,7 +251,7 @@ private static String toStringBandwidth(PathMetadata meta) {
 
   private static String toStringGeo(PathMetadata meta) {
     StringBuilder s = new StringBuilder("[");
-    for (PathMetadata.GeoCoordinates g : meta.getGeoList()) {
+    for (PathMetadata.GeoCoordinates g : meta.getGeoCoordinates()) {
       if (s.length() > 1) {
         s.append(" > ");
       }
@@ -269,7 +269,7 @@ private static String toStringGeo(PathMetadata meta) {
 
   private static String toStringLinkType(PathMetadata meta) {
     StringBuilder s = new StringBuilder("[");
-    for (PathMetadata.LinkType lt : meta.getLinkTypeList()) {
+    for (PathMetadata.LinkType lt : meta.getLinkTypes()) {
       if (s.length() > 1) {
         s.append(", ");
       }
@@ -312,12 +312,12 @@ private static String toStringEPIC(PathMetadata meta) {
   private static String toStringNotes(PathMetadata meta) {
     StringBuilder s = new StringBuilder("[");
     int i = 0;
-    for (String note : meta.getNotesList()) {
+    for (String note : meta.getNotes()) {
       if (note != null && !note.isEmpty()) {
         if (s.length() > 1) {
           s.append(", ");
         }
-        long isdAs = meta.getInterfacesList().get(Math.max(0, i * 2 - 1)).getIsdAs();
+        long isdAs = meta.getInterfaces().get(Math.max(0, i * 2 - 1)).getIsdAs();
         s.append(ScionUtil.toStringIA(isdAs));
         s.append(": \"").append(note).append("\"");
       }

diff --git a/src/main/java/org/scion/cli/Traceroute.java b/src/main/java/org/scion/cli/Traceroute.java
@@ -19,7 +19,6 @@
 import java.io.*;
 import java.net.*;
 import java.util.*;
-import java.util.concurrent.atomic.AtomicBoolean;
 import org.scion.cli.util.Errors;
 import org.scion.cli.util.ExitCodeException;
 import org.scion.cli.util.Prober;
@@ -34,7 +33,7 @@ public class Traceroute {
 
   private Integer localPort;
   private boolean startShim = true;
-  private long localIsdAs = 0;
+  private Long localIsdAs;
   private InetAddress localIP = null;
   private ScionAddress dstAddress;
   private String dstUrl;
@@ -130,9 +129,8 @@ public void run() throws IOException {
     }
 
     if (paths.isEmpty()) {
-      String src = ScionUtil.toStringIA(service.getLocalIsdAs());
       String dst = ScionUtil.toStringIA(dstAddress.getIsdAs());
-      throw new ExitCodeException(2, "No path found from " + src + " to " + dst);
+      throw new ExitCodeException(2, "No path found from " + localIsdAses(service) + " to " + dst);
     }
 
     Path path;
@@ -145,7 +143,7 @@ public void run() throws IOException {
         }
       }
       if (newPaths.isEmpty()) {
-        String src = ScionUtil.toStringIA(Scion.defaultService().getLocalIsdAs());
+        String src = localIsdAses(service);
         String dst = ScionUtil.toStringIA(dstAddress.getIsdAs());
         throw new ExitCodeException(2, "No path found from " + src + " to " + dst);
       }
@@ -154,6 +152,10 @@ public void run() throws IOException {
       path = paths.get(0);
     }
 
+    send(path);
+  }
+
+  private void send(Path path) throws IOException {
     String localAddress;
     try (ScionDatagramChannel channel = ScionDatagramChannel.open()) {
       channel.connect(path);
@@ -166,20 +168,18 @@ public void run() throws IOException {
       builder.setLocalPort(localPort);
     }
     // No concurrency, but must be final
-    AtomicBoolean scmpError = new AtomicBoolean(false);
     try (ScmpSender sender = builder.build()) {
       sender.setTimeOut(timeoutMs);
-      sender.setScmpErrorListener(
+      sender.setScmpErrorHandler(
           e -> {
             println("SCMP Error: " + e.getTypeCode().getText());
-            scmpError.set(true);
+            return false;
           });
       println("Listening on port " + sender.getLocalAddress().getPort() + " ...");
       println("Resolved local address: ");
       println("  " + localAddress);
       printPath(path);
 
-      // TODO this may throw an IOException if external interface is down
       List<Scmp.TracerouteMessage> results = sender.sendTracerouteRequest(path);
       int nTimeouts = 0;
       for (Scmp.TracerouteMessage msg : results) {
@@ -201,24 +201,23 @@ public void run() throws IOException {
         }
         throw new ExitCodeException(1, "Number of timeouts: " + nTimeouts + msg);
       }
-    } catch (IOException e) {
-      if (scmpError.getAndSet(false)) {
-        // Ignore, we already reported the error
-        return;
-      }
-      throw e;
     }
   }
 
   private static void printPath(Path path) {
     String nl = System.lineSeparator();
-    StringBuilder sb = new StringBuilder();
     // sb.append("Actual local address:").append(nl);
     // sb.append("  ").append(channel.getLocalAddress().getAddress().getHostAddress()).append(nl);
-    sb.append("Using path:").append(nl);
-    sb.append("  Hops: ").append(ScionUtil.toStringPath(path.getMetadata()));
-    sb.append(" MTU: ").append(path.getMetadata().getMtu());
-    sb.append(" NextHop: ").append(path.getMetadata().getInterface().getAddress()).append(nl);
-    println(sb.toString());
+    String sb =
+        "Using path:"
+            + nl
+            + " Hops: "
+            + ScionUtil.toStringPath(path.getMetadata())
+            + " MTU: "
+            + path.getMetadata().getMtu()
+            + " NextHop: "
+            + path.getMetadata().getLocalInterface().getAddress()
+            + nl;
+    println(sb);
   }
 }
diff --git a/src/main/java/org/scion/cli/util/Prober.java b/src/main/java/org/scion/cli/util/Prober.java
@@ -109,10 +109,8 @@ public void onError(Scmp.ErrorMessage msg) {
         m2 = ScmpParser.consume(ByteBuffer.wrap(msg.getCause()), (ResponsePath) msg.getPath());
         Scmp.TypeCode tc = m2.getTypeCode();
         if (tc == Scmp.TypeCode.TYPE_128 || tc == Scmp.TypeCode.TYPE_130) {
-          if (m2 instanceof Scmp.TimedMessage) {
-            int sn = ((Scmp.TimedMessage) m2).getSequenceNumber();
-            result.put(sn, Status.SCMP);
-          }
+          int sn = ((Scmp.TimedMessage) m2).getSequenceNumber();
+          result.put(sn, Status.SCMP);
         }
       } catch (RuntimeException e) {
         Util.println("Could not decode Scmp Error (" + msg.getTypeCode() + "): " + e.getMessage());

diff --git a/src/main/java/org/scion/cli/util/Util.java b/src/main/java/org/scion/cli/util/Util.java
@@ -92,6 +92,17 @@ public static double round(double d, int nDigits) {
     return Math.round(d * div) / div;
   }
 
+  public static String localIsdAses(ScionService service) {
+    if (service.getLocalIsdAses().isEmpty()) {
+      return "[]";
+    }
+    StringBuilder ret = new StringBuilder("[");
+    for (long ia : service.getLocalIsdAses()) {
+      ret.append(ScionUtil.toStringIA(ia)).append(",");
+    }
+    return ret.substring(0, ret.length() - 1) + "]";
+  }
+
   public static void prepareShim(boolean startShim, Integer port) {
     if (startShim && port != null && port.equals(Constants.SCMP_PORT)) {
       throw new ExitCodeException(