com

README.md

@@ -2,4 +2,12 @@
 1. Get the `-server.jar` or `-client.jar` and make a new directory for it
 2. Run the JAR, then stop it
 3. Configure in `config`
-4. Now run the JAR. Done!
+4. Now run the JAR. Done!
+
+# Client config
+- `remote` the autopeerer server websocket URL
+- `wireguard.directory` directory for WireGuard config files
+- `bird.directory` directory for BIRD config files
+- `link-local` the link local for peering
+- `stack.ipv4` IPv4 availability. Values: `no`, `yes`, `restricted`
+- `stack.ipv6` same but for IPv6

pom.xml

@@ -20,11 +20,6 @@
             <artifactId>Java-WebSocket</artifactId>
             <version>1.5.7</version>
         </dependency>
-        <dependency>
-            <groupId>com.github.seancfoley</groupId>
-            <artifactId>ipaddress</artifactId>
-            <version>5.5.1</version>
-        </dependency>
         <dependency>
             <groupId>org.json</groupId>
             <artifactId>json</artifactId>

src/main/java/eu/m724/autopeerer/client/ClientPrefs.java

@@ -0,0 +1,45 @@
+package eu.m724.autopeerer.client;
+
+public class ClientPrefs {
+    private static ClientPrefs INSTANCE;
+
+    private final boolean ipv4, restricted4, ipv6, restricted6;
+
+    private ClientPrefs(  boolean ipv4, boolean restricted4, boolean ipv6, boolean restricted6) {
+        this.ipv4 = ipv4;
+        this.restricted4 = restricted4;
+        this.ipv6 = ipv6;
+        this.restricted6 = restricted6;
+    }
+
+    public static void init(ClientConfiguration configuration) {
+        var ipv4 = configuration.getString("stack.ipv4");
+        var ipv6 = configuration.getString("stack.ipv6");
+
+        INSTANCE = new ClientPrefs(
+                ipv4.equalsIgnoreCase("yes") || ipv4.equalsIgnoreCase("restricted"),
+                ipv4.equalsIgnoreCase("restricted"),
+                ipv6.equalsIgnoreCase("yes") || ipv6.equalsIgnoreCase("restricted"),
+                ipv6.equalsIgnoreCase("restricted")
+        );
+    }
+
+    /* */
+
+    public static boolean ipv4Supported() {
+        return INSTANCE.ipv4;
+    }
+
+    public static boolean ipv6Supported() {
+        return INSTANCE.ipv6;
+    }
+    
+    public static boolean ipv4Restricted() {
+        return INSTANCE.restricted4;
+    }
+
+    public static boolean ipv6Restricted() {
+        return INSTANCE.restricted6;
+    }
+
+}

src/main/java/eu/m724/autopeerer/client/Main.java

@@ -23,6 +23,8 @@ public class Main {
             return;
         }
 
+        ClientPrefs.init(config);
+
         URI serverUri = URI.create(config.getString("remote"));
 
         var wireGuardLive = new WireGuardLive(new File(config.getString("wireguard.directory")));

src/main/java/eu/m724/autopeerer/client/PacketHandler.java

@@ -5,6 +5,7 @@ import eu.m724.autopeerer.client.bird.BirdSession;
 import eu.m724.autopeerer.client.wireguard.WireGuardKeys;
 import eu.m724.autopeerer.client.wireguard.WireGuardLive;
 import eu.m724.autopeerer.client.wireguard.WireGuardSession;
+import eu.m724.autopeerer.common.AddressTools;
 import eu.m724.autopeerer.common.packet.Packet;
 import eu.m724.autopeerer.common.packet.Packets;
 import eu.m724.autopeerer.common.packet.s2c.PingRequestPacket;
@@ -14,6 +15,7 @@ import eu.m724.autopeerer.common.packet.c2s.SessionResponsePacket;
 
 import java.io.BufferedReader;
 import java.io.IOException;
+import java.net.UnknownHostException;
 import java.nio.BufferUnderflowException;
 import java.nio.ByteBuffer;
 import java.nio.file.FileAlreadyExistsException;
@@ -96,6 +98,24 @@ public class PacketHandler {
     }
 
     private void handleSessionRequest(SessionRequestPacket packet) {
+        // validate endpoint
+        var resolved = false;
+        try {
+            if (ClientPrefs.ipv6Supported()) {
+                var res = AddressTools.resolve(packet.endpointHost, true);
+                resolved = res != null;
+            }
+            if (!resolved && ClientPrefs.ipv4Supported()) {
+                var res = AddressTools.resolve(packet.endpointHost, true);
+                resolved = res != null;
+            }
+        } catch (UnknownHostException | AddressTools.MultipleRecordsException ignored) { }
+
+        if (!resolved) {
+            Packets.send(new SessionResponsePacket(packet.asn, SessionResponsePacket.SessionResult.ERROR_RESOLVE, -1, null), sender);
+            return;
+        }
+
         var privateKey = WireGuardKeys.generatePrivateKey();
         var publicKey = WireGuardKeys.derivePublicKey(privateKey);
 
@@ -104,8 +124,8 @@ public class PacketHandler {
             port = (int) (packet.asn % 10000);
         }
 
-        var wireGuardSession = new WireGuardSession(port, privateKey, serverLinkLocal, packet.linkLocal.toCompressedString(), packet.endpointHost + ":" + packet.endpointPort, packet.publicKey);
+        var wireGuardSession = new WireGuardSession(port, privateKey, serverLinkLocal, packet.linkLocal.getHostAddress(), packet.endpointHost + ":" + packet.endpointPort, packet.publicKey);
-        var birdSession = new BirdSession(packet.asn, packet.linkLocal.toCompressedString());
+        var birdSession = new BirdSession(packet.asn, packet.linkLocal.getHostAddress());
 
         try {
             wireGuardLive.saveSession(packet.asn, wireGuardSession);
@@ -115,9 +135,10 @@ public class PacketHandler {
             Packets.send(new SessionResponsePacket(packet.asn, SessionResponsePacket.SessionResult.OK, wireGuardSession.listenPort(), publicKey), sender);
         } catch (FileAlreadyExistsException e) {
             System.err.println("Tried to create a session which already exists: AS" + packet.asn);
-            Packets.send(new SessionResponsePacket(packet.asn, SessionResponsePacket.SessionResult.DUPLICATE, -1, null), sender);
+            Packets.send(new SessionResponsePacket(packet.asn, SessionResponsePacket.SessionResult.ERROR_DUPLICATE, -1, null), sender);
         } catch (IOException e) {
-            Packets.send(new SessionResponsePacket(packet.asn, SessionResponsePacket.SessionResult.ERROR, -1, null), sender);
+            Packets.send(new SessionResponsePacket(packet.asn, SessionResponsePacket.SessionResult.ERROR_OTHER, -1, null), sender);
+            System.err.println("Failed to save session");
             throw new RuntimeException(e);
         }
     }

src/main/java/eu/m724/autopeerer/common/AddressTools.java

@@ -0,0 +1,50 @@
+package eu.m724.autopeerer.common;
+
+import java.net.Inet4Address;
+import java.net.Inet6Address;
+import java.net.InetAddress;
+import java.net.UnknownHostException;
+import java.util.Arrays;
+
+public class AddressTools {
+    private static boolean isIp(InetAddress address, boolean ipv6) {
+        return ipv6 ? address instanceof Inet6Address : address instanceof Inet4Address;
+    }
+
+    /**
+     * Checks if address is link local
+     * @param address the address
+     * @return whether it's IPv6 and link local
+     */
+    public static boolean isLinkLocal(InetAddress address) {
+        if (isIp(address, true)) return false;
+        var bytes = address.getAddress();
+
+        return bytes[0] == -2 && bytes[1] >= 0 && bytes[1] <= 63;
+    }
+
+    /**
+     * Resolve a host to IPv4 or IPv6
+     *
+     * @param host the host to resolve
+     * @param ipv6 whether to resolve IPv6 or not (IPv4)
+     * @return The resolved IP or null
+     * @throws UnknownHostException if host is invalid
+     * @throws MultipleRecordsException if host has multiple records
+     */
+    public static InetAddress resolve(String host, boolean ipv6) throws UnknownHostException, MultipleRecordsException {
+        var addr = Arrays.stream(InetAddress.getAllByName(host))
+                .filter(address -> isIp(address, ipv6))
+                .toList();
+
+        if (addr.size() > 1)
+            throw new MultipleRecordsException();
+
+        return addr.get(0);
+    }
+
+    /**
+     * If a host has multiple A or AAAA records, and it's impossible to pick one
+     */
+    public static class MultipleRecordsException extends Exception {}
+}

src/main/java/eu/m724/autopeerer/common/packet/c2s/SessionResponsePacket.java

@@ -23,7 +23,7 @@ public class SessionResponsePacket implements Packet<SessionResponsePacket> {
         return 2;
     }
 
-    public static SessionResponsePacket deserialize(ByteBuffer buffer) throws Exception {
+    public static SessionResponsePacket deserialize(ByteBuffer buffer) {
         var asn = Integer.toUnsignedLong(buffer.getInt());
         var result = SessionResult.values()[buffer.get()];
 
@@ -57,6 +57,6 @@ public class SessionResponsePacket implements Packet<SessionResponsePacket> {
     }
 
     public enum SessionResult {
-        OK, ERROR, DUPLICATE
+        OK, ERROR_DUPLICATE, ERROR_RESOLVE, ERROR_OTHER
     }
 }

src/main/java/eu/m724/autopeerer/common/packet/s2c/SessionRequestPacket.java

@@ -1,39 +1,33 @@
 package eu.m724.autopeerer.common.packet.s2c;
 
+import eu.m724.autopeerer.common.AddressTools;
 import eu.m724.autopeerer.common.packet.Packet;
-import inet.ipaddr.HostName;
-import inet.ipaddr.HostNameException;
-import inet.ipaddr.IPAddressString;
-import inet.ipaddr.ipv6.IPv6Address;
 
 import java.net.IDN;
+import java.net.InetAddress;
 import java.nio.ByteBuffer;
 import java.nio.charset.StandardCharsets;
 import java.util.Base64;
 
 public class SessionRequestPacket implements Packet<SessionRequestPacket> {
     public final long asn;
-    public final IPv6Address linkLocal;
+    public final InetAddress linkLocal;
     public final String publicKey;
     public final String endpointHost;
     public final int endpointPort;
 
-    public SessionRequestPacket(long asn, IPv6Address linkLocal, String publicKey, String endpointHost, int endpointPort) {
+    public SessionRequestPacket(long asn, InetAddress linkLocal, String publicKey, String endpointHost, int endpointPort) {
         this.asn = asn;
         assert asn < 0xFFFFFFFFL;
 
         this.linkLocal = linkLocal;
-        assert new IPAddressString("fe80::/10").getAddress().contains(linkLocal);
+        assert AddressTools.isLinkLocal(linkLocal);
 
         this.publicKey = publicKey;
         assert Base64.getDecoder().decode(publicKey).length == 32;
 
+        // testing is done at another point
         this.endpointHost = IDN.toASCII(endpointHost, IDN.ALLOW_UNASSIGNED);
-        try {
-            new HostName(endpointHost).validate();
-        } catch (HostNameException e) {
-            throw new RuntimeException(e);
-        }
 
         this.endpointPort = endpointPort;
         assert endpointPort > 0 && endpointPort < 65536;
@@ -49,7 +43,7 @@ public class SessionRequestPacket implements Packet<SessionRequestPacket> {
 
         var ll = new byte[16];
         buffer.get(ll);
-        var linkLocal = new IPv6Address(ll);
+        var linkLocal = InetAddress.getByAddress(ll);
 
         var pk = new byte[32];
         buffer.get(pk);
@@ -70,7 +64,7 @@ public class SessionRequestPacket implements Packet<SessionRequestPacket> {
         var buffer = ByteBuffer.allocate(55 + endpointHost.length());
 
         buffer.putInt((int) asn);
-        buffer.put(linkLocal.getBytes()); // 16b
+        buffer.put(linkLocal.getAddress()); // 16b
         buffer.put(Base64.getDecoder().decode(publicKey)); // 32b
         buffer.putShort((short) endpointPort); // 2b
         buffer.put((byte) endpointHost.length()); // 1b

src/main/java/eu/m724/autopeerer/server/ClientState.java

@@ -6,15 +6,12 @@ import eu.m724.autopeerer.common.packet.c2s.PingResponsePacket;
 import eu.m724.autopeerer.common.packet.c2s.SessionResponsePacket;
 import eu.m724.autopeerer.common.packet.s2c.PingRequestPacket;
 import eu.m724.autopeerer.common.packet.s2c.SessionRequestPacket;
-import inet.ipaddr.ipv6.IPv6Address;
 import org.java_websocket.WebSocket;
 
 import java.net.InetAddress;
-import java.net.UnknownHostException;
 import java.nio.ByteBuffer;
 import java.util.HashMap;
 import java.util.Map;
-import java.util.concurrent.Callable;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.ThreadLocalRandom;
 import java.util.function.Consumer;
@@ -52,7 +49,7 @@ public class ClientState {
         return future;
     }
 
-    CompletableFuture<SessionResponsePacket> session(long asn, IPv6Address linkLocal, String publicKey, String endpointHost, int endpointPort) {
+    CompletableFuture<SessionResponsePacket> session(long asn, InetAddress linkLocal, String publicKey, String endpointHost, int endpointPort) {
         var future = new CompletableFuture<SessionResponsePacket>();
 
         sessionConsumers.put(asn, future::complete);
@@ -66,9 +63,8 @@ public class ClientState {
 
     /* Packet functions */
 
-    private Map<Short, Consumer<PingResponsePacket>> pingConsumers = new HashMap<>();
+    private final Map<Short, Consumer<PingResponsePacket>> pingConsumers = new HashMap<>();
-    private Map<Long, Consumer<SessionResponsePacket>> sessionConsumers = new HashMap<>();
+    private final Map<Long, Consumer<SessionResponsePacket>> sessionConsumers = new HashMap<>();
-
 
     void onPacketReceived(Packet<?> p) {
         if (p instanceof PingResponsePacket packet) {

src/main/java/eu/m724/autopeerer/server/Main.java

@@ -8,17 +8,11 @@ import java.util.Set;
 
 public class Main {
     public static void main(String[] args) throws IOException {
-        System.out.println("Hello world!");
-
         var config = new ServerConfiguration();
         Set<Node> nodes;
         try {
             config.load();
             nodes = config.loadNodes();
-            if (nodes.isEmpty())
-                System.err.println("Loaded 0 nodes. No client will be able to connect.");
-            else
-                System.out.printf("Loaded %d nodes.\n", nodes.size());
         } catch (IOException e) {
             throw new RuntimeException("Failed to load configuration", e);
         }
@@ -28,7 +22,15 @@ public class Main {
             return;
         }
 
+        if (nodes.isEmpty())
+            System.err.println("Loaded 0 nodes. No client will be able to connect.");
+        else
+            System.out.printf("Loaded %d nodes.\n", nodes.size());
+
+
+
         var packetHandler = new PacketHandler(nodes);
+
         var server = new MyWebsocketServer(
                 new InetSocketAddress(config.getString("socket.address"), config.getInt("socket.port")),
                 packetHandler

src/main/java/eu/m724/autopeerer/server/MyHttpHandler.java

@@ -4,9 +4,6 @@ import com.sun.net.httpserver.HttpExchange;
 import com.sun.net.httpserver.HttpHandler;
 import eu.m724.autopeerer.common.packet.c2s.PingResponsePacket;
 import eu.m724.autopeerer.common.packet.c2s.SessionResponsePacket;
-import inet.ipaddr.IPAddress;
-import inet.ipaddr.IPAddressString;
-import inet.ipaddr.ipv6.IPv6Address;
 import org.json.JSONArray;
 import org.json.JSONException;
 import org.json.JSONObject;
@@ -43,7 +40,7 @@ public class MyHttpHandler implements HttpHandler {
             inner(exchange);
         } catch (IOException e) {
             exchange.sendResponseHeaders(500, -1);
-        } catch (EndException e) { }
+        } catch (EndException ignored) { }
     }
 
     private void inner(HttpExchange exchange) throws IOException, EndException {
@@ -116,7 +113,7 @@ public class MyHttpHandler implements HttpHandler {
                             sseWrite(exchange, response.toString());
                         } catch (IOException e) {
                             e.printStackTrace();
-                        } catch (EndException e) { }
+                        } catch (EndException ignored) { }
 
                         return (Void) null;
                     });
@@ -165,7 +162,7 @@ public class MyHttpHandler implements HttpHandler {
                 try {
                     future = node.getClient().session(
                             json.getLong("asn"),
-                            new IPAddressString(json.getString("linkLocal")).getAddress().toIPv6(),
+                            InetAddress.getByName(json.getString("linkLocal")),
                             json.getString("publicKey"),
                             json.getString("endpointHost"),
                             json.getInt("endpointPort")

src/main/java/eu/m724/autopeerer/server/ServerConfiguration.java

@@ -6,6 +6,7 @@ import java.io.File;
 import java.io.FileInputStream;
 import java.io.FileNotFoundException;
 import java.io.IOException;
+import java.nio.file.Files;
 import java.util.HashSet;
 import java.util.Properties;
 import java.util.Set;
@@ -17,7 +18,14 @@ public class ServerConfiguration extends Configuration {
 
     public Set<Node> loadNodes() throws IOException {
         var nd = new File(directory, "nodes");
-        nd.mkdir();
+
+        if (!nd.exists()) {
+            nd.mkdir();
+            var f = new File(nd, "node1.properties");
+            try (var is = getClass().getClassLoader().getResourceAsStream(f.getName())) {
+                Files.write(f.toPath(), is.readAllBytes());
+            }
+        }
 
         var nodes = new HashSet<Node>();
 

src/main/resources/client.properties

@@ -1,4 +1,12 @@
+# The server websocket
 remote=ws://127.0.0.1:8002
+# Where are WG and BIRD configs located
 wireguard.directory=config/wg
 bird.directory=config/bird
-link-local=fe80::129:0
+
+# Link local used for peering
+link-local=fe80::129:0
+# Is IPv4 available? Yes, no, restricted
+stack.ipv4=yes
+# Is IPv6 available? Yes, no, restricted
+stack.ipv6=yes

src/main/resources/nodes/node1.properties

@@ -0,0 +1,3 @@
+key=AAAAAAAAAAA=
+name="Node Number One"
+host=example.com