SAM: Add support for Datagram 2/3 (proposal 163)

2025-08-18 14:24:01 -04:00
6 changed files with 202 additions and 45 deletions
--- a/apps/sam/java/src/net/i2p/sam/PrimarySession.java
+++ b/apps/sam/java/src/net/i2p/sam/PrimarySession.java
@@ -23,6 +23,7 @@ import net.i2p.client.streaming.I2PSocket;
 import net.i2p.data.DataFormatException;
 import net.i2p.data.DataHelper;
 import net.i2p.data.Destination;
+import net.i2p.data.Hash;
 import net.i2p.util.I2PAppThread;
 import net.i2p.util.Log;

@@ -123,8 +124,11 @@ class PrimarySession extends SAMv3StreamSession implements SAMDatagramReceiver,
 				if (spr != null) {
 					try {
 						listenProtocol = Integer.parseInt(spr);
-						// RAW can't listen on streaming protocol
+						// RAW can't listen on streaming or DG protocols
 						if (listenProtocol < 0 || listenProtocol > 255 ||
+						    listenProtocol == I2PSession.PROTO_DATAGRAM ||
+						    listenProtocol == I2PSession.PROTO_DATAGRAM2 ||
+						    listenProtocol == I2PSession.PROTO_DATAGRAM3 ||
 						    listenProtocol == I2PSession.PROTO_STREAMING)
 							return "Bad RAW LISTEN_PPROTOCOL " + spr;
 					} catch (NumberFormatException nfe) {
@@ -134,11 +138,23 @@ class PrimarySession extends SAMv3StreamSession implements SAMDatagramReceiver,
 				SAMv3RawSession ssess = new SAMv3RawSession(nick, props, handler, isess, listenProtocol, listenPort, dgs);
 				subhandler.setSession(ssess);
 				sess = ssess;
-			} else if (style.equals("DATAGRAM")) {
+			} else if (style.equals("DATAGRAM") ||
+				   style.equals("DATAGRAM2") ||
+				   style.equals("DATAGRAM3")) {
 				if (!props.containsKey("PORT"))
 					return "DATAGRAM subsession must specify PORT";
-				listenProtocol = I2PSession.PROTO_DATAGRAM;
-				SAMv3DatagramSession ssess = new SAMv3DatagramSession(nick, props, handler, isess, listenPort, dgs);
+				int v;
+				if (style.equals("DATAGRAM")) {
+					listenProtocol = I2PSession.PROTO_DATAGRAM;
+					v = 1;
+				} else if (style.equals("DATAGRAM2")) {
+					listenProtocol = I2PSession.PROTO_DATAGRAM2;
+					v = 2;
+				} else {
+					listenProtocol = I2PSession.PROTO_DATAGRAM3;
+					v = 3;
+				}
+				SAMv3DatagramSession ssess = new SAMv3DatagramSession(nick, props, handler, isess, listenPort, dgs, v);
 				subhandler.setSession(ssess);
 				sess = ssess;
 			} else if (style.equals("STREAM")) {
@@ -212,6 +228,15 @@ class PrimarySession extends SAMv3StreamSession implements SAMDatagramReceiver,
 		throw new IOException("primary session");
 	}

+	/**
+	 *  @throws IOException always
+	 *  @since 0.9.68
+	 */
+	public void receiveDatagramBytes(Hash sender, byte[] data, int proto,
+	                                 int fromPort, int toPort) throws IOException {
+		throw new IOException("primary session");
+	}
+
 	/**
 	 *  Does nothing.
 	 */
--- a/apps/sam/java/src/net/i2p/sam/SAMDatagramReceiver.java
+++ b/apps/sam/java/src/net/i2p/sam/SAMDatagramReceiver.java
@@ -11,6 +11,7 @@ package net.i2p.sam;
 import java.io.IOException;

 import net.i2p.data.Destination;
+import net.i2p.data.Hash;

 /**
 * Interface for sending raw data to a SAM client
@@ -29,6 +30,20 @@ interface SAMDatagramReceiver {
     */
    public void receiveDatagramBytes(Destination sender, byte data[], int proto, int fromPort, int toPort) throws IOException;

+    /**
+     * Send a byte array to a SAM client.
+     * Only for Datagram3, where the sender Destination is not available, only the hash.
+     *
+     * @param sender Hash
+     * @param data Byte array to be received
+     * @param proto I2CP protocol, almost certainly 20 (DATAGRAM3)
+     * @param fromPort I2CP from port
+     * @param toPort I2CP to port
+     * @since 0.9.68
+     * @throws IOException 
+     */
+    public void receiveDatagramBytes(Hash sender, byte data[], int proto, int fromPort, int toPort) throws IOException;
+
    /**
     * Stop receiving data.
     *
--- a/apps/sam/java/src/net/i2p/sam/SAMDatagramSession.java
+++ b/apps/sam/java/src/net/i2p/sam/SAMDatagramSession.java
@@ -12,17 +12,22 @@ import java.io.IOException;
 import java.io.InputStream;
 import java.util.Properties;

+import net.i2p.I2PAppContext;
 import net.i2p.client.I2PSession;
 import net.i2p.client.I2PSessionException;
+import net.i2p.client.datagram.Datagram2;
+import net.i2p.client.datagram.Datagram3;
 import net.i2p.client.datagram.I2PDatagramDissector;
 import net.i2p.client.datagram.I2PDatagramMaker;
 import net.i2p.client.datagram.I2PInvalidDatagramException;
 import net.i2p.data.DataFormatException;
 import net.i2p.data.Destination;
+import net.i2p.data.Hash;
 import net.i2p.util.Log;

 /**
 * SAM DATAGRAM session class.
+ * Supports DG2/3 as of 0.9.68
 *
 * @author human
 */
@@ -33,28 +38,40 @@ class SAMDatagramSession extends SAMMessageSession {
    // FIXME make final after fixing SAMv3DatagramSession override
    protected SAMDatagramReceiver recv;
    private final I2PDatagramMaker dgramMaker;
-    private final I2PDatagramDissector dgramDissector = new I2PDatagramDissector();
+    private final I2PDatagramDissector dgramDissector;
+    private final int version;

    /**
     * Create a new SAM DATAGRAM session.
+     * v1/v2 (DG1 only) or v3 (DG 1/2/3)
     *
     * @param dest Base64-encoded destination (private key)
     * @param props Properties to setup the I2P session
     * @param recv Object that will receive incoming data
+     * @param v datagram version 1/2/3
     * @throws IOException
     * @throws DataFormatException
     * @throws I2PSessionException 
     */
    protected SAMDatagramSession(String dest, Properties props,
-                              SAMDatagramReceiver recv) throws IOException, 
+                              SAMDatagramReceiver recv, int v) throws IOException, 
                              DataFormatException, I2PSessionException {
        super(dest, props);
-        this.recv = recv;
-        dgramMaker = new I2PDatagramMaker(getI2PSession());
+        if (v == 1) {
+            dgramMaker = new I2PDatagramMaker(getI2PSession());
+            dgramDissector = new I2PDatagramDissector();
+        } else if (v == 2 || v == 3) {
+            dgramMaker = null;
+            dgramDissector = null;
+        } else {
+            throw new IllegalArgumentException("Bad version: " + v);
+        }
+        version = v;
    }

    /**
     * Create a new SAM DATAGRAM session.
+     * v1/v2 only, DG1 only
     *
     * Caller MUST call start().
     *
@@ -64,27 +81,41 @@ class SAMDatagramSession extends SAMMessageSession {
     * @throws IOException
     * @throws DataFormatException
     * @throws I2PSessionException 
+     * @deprecated unused
     */
+    @Deprecated
    public SAMDatagramSession(InputStream destStream, Properties props,
                              SAMDatagramReceiver recv) throws IOException, 
                              DataFormatException, I2PSessionException {
        super(destStream, props);
        this.recv = recv;
        dgramMaker = new I2PDatagramMaker(getI2PSession());
+        dgramDissector = new I2PDatagramDissector();
+        version = 1;
    }

    /**
     * Create a new SAM DATAGRAM session on an existing I2P session.
+     * v3 only, DG 1/2/3
     *
-     * @param props unused for now
+     * @param v datagram version 1/2/3
     * @since 0.9.25
     */
    protected SAMDatagramSession(I2PSession sess, Properties props, int listenPort,
-                              SAMDatagramReceiver recv) throws IOException, 
+                              SAMDatagramReceiver recv, int v) throws IOException, 
                              DataFormatException, I2PSessionException {
        super(sess, I2PSession.PROTO_DATAGRAM, listenPort);
        this.recv = recv;
-        dgramMaker = new I2PDatagramMaker(getI2PSession());
+        if (v == 1) {
+            dgramMaker = new I2PDatagramMaker(getI2PSession());
+            dgramDissector = new I2PDatagramDissector();
+        } else if (v == 2 || v == 3) {
+            dgramMaker = null;
+            dgramDissector = null;
+        } else {
+            throw new IllegalArgumentException("Bad version: " + v);
+        }
+        version = v;
    }

    /**
@@ -92,7 +123,7 @@ class SAMDatagramSession extends SAMMessageSession {
     *
     * @param dest Destination
     * @param data Bytes to be sent
-     * @param proto ignored, will always use PROTO_DATAGRAM (17)
+     * @param proto ignored, will always use PROTO_DATAGRAM (17), PROTO_DATAGRAM2 (19), or PROTO_DATAGRAM3 (20)
     *
     * @return True if the data was sent, false otherwise
     * @throws DataFormatException on unknown / bad dest
@@ -102,16 +133,27 @@ class SAMDatagramSession extends SAMMessageSession {
                             int fromPort, int toPort) throws DataFormatException, I2PSessionException {
        if (data.length > DGRAM_SIZE_MAX)
            throw new DataFormatException("Datagram size exceeded (" + data.length + ")");
-        byte[] dgram ;
-        synchronized (dgramMaker) {
-            dgram = dgramMaker.makeI2PDatagram(data);
+        byte[] dgram;
+        if (version == 1) {
+            synchronized (dgramMaker) {
+                dgram = dgramMaker.makeI2PDatagram(data);
+            }
+            proto = I2PSession.PROTO_DATAGRAM;
+        } else if (version == 2) {
+            Hash h = new Destination(dest).calculateHash();
+            dgram = Datagram2.make(I2PAppContext.getGlobalContext(), getI2PSession(), data, h);
+            proto = I2PSession.PROTO_DATAGRAM2;
+        } else {
+            dgram = Datagram3.make(I2PAppContext.getGlobalContext(), getI2PSession(), data);
+            proto = I2PSession.PROTO_DATAGRAM3;
        }
-        return sendBytesThroughMessageSession(dest, dgram, I2PSession.PROTO_DATAGRAM, fromPort, toPort);
+        return sendBytesThroughMessageSession(dest, dgram, proto, fromPort, toPort);
    }

    /**
     * Send bytes through a SAM DATAGRAM session.
     *
+     * @param proto ignored, will always use PROTO_DATAGRAM (17), PROTO_DATAGRAM2 (19), or PROTO_DATAGRAM3 (20)
     * @since 0.9.25
     */
    public boolean sendBytes(String dest, byte[] data, int proto,
@@ -121,22 +163,50 @@ class SAMDatagramSession extends SAMMessageSession {
                                 throws DataFormatException, I2PSessionException {
        if (data.length > DGRAM_SIZE_MAX)
            throw new DataFormatException("Datagram size exceeded (" + data.length + ")");
-        byte[] dgram ;
-        synchronized (dgramMaker) {
-            dgram = dgramMaker.makeI2PDatagram(data);
+        byte[] dgram;
+        if (version == 1) {
+            synchronized (dgramMaker) {
+                dgram = dgramMaker.makeI2PDatagram(data);
+            }
+            proto = I2PSession.PROTO_DATAGRAM;
+        } else if (version == 2) {
+            Hash h = new Destination(dest).calculateHash();
+            dgram = Datagram2.make(I2PAppContext.getGlobalContext(), getI2PSession(), data, h);
+            proto = I2PSession.PROTO_DATAGRAM2;
+        } else {
+            dgram = Datagram3.make(I2PAppContext.getGlobalContext(), getI2PSession(), data);
+            proto = I2PSession.PROTO_DATAGRAM3;
        }
-        return sendBytesThroughMessageSession(dest, dgram, I2PSession.PROTO_DATAGRAM, fromPort, toPort,
+        return sendBytesThroughMessageSession(dest, dgram, proto, fromPort, toPort,
                                              sendLeaseSet, sendTags,tagThreshold, expiration);
    }

    protected void messageReceived(byte[] msg, int proto, int fromPort, int toPort) {
        byte[] payload;
        Destination sender;
+        Hash h;
        try {
-            synchronized (dgramDissector) {
-                dgramDissector.loadI2PDatagram(msg);
-                sender = dgramDissector.getSender();
-                payload = dgramDissector.extractPayload();
+            if (version == 1 && proto == I2PSession.PROTO_DATAGRAM) {
+                synchronized (dgramDissector) {
+                    dgramDissector.loadI2PDatagram(msg);
+                    sender = dgramDissector.getSender();
+                    payload = dgramDissector.extractPayload();
+                }
+                h = null;
+            } else if (version == 2 && proto == I2PSession.PROTO_DATAGRAM2) {
+                Datagram2 dg = Datagram2.load(I2PAppContext.getGlobalContext(), getI2PSession(), msg);
+                sender = dg.getSender();
+                payload = dg.getPayload();
+                h = null;
+            } else if (version == 3 && proto == I2PSession.PROTO_DATAGRAM3) {
+                Datagram3 dg = Datagram3.load(I2PAppContext.getGlobalContext(), getI2PSession(), msg);
+                sender = null;
+                payload = dg.getPayload();
+                h = dg.getSender();
+            } else {
+                if (_log.shouldDebug())
+                    _log.debug("Dropping mismatched protocol, datagram version=" + version + " proto=" + proto);
+                return;
            }
        } catch (DataFormatException e) {
            if (_log.shouldLog(Log.DEBUG)) {
@@ -151,7 +221,13 @@ class SAMDatagramSession extends SAMMessageSession {
        }

        try {
-            recv.receiveDatagramBytes(sender, payload, proto, fromPort, toPort);
+            if (sender != null) {
+                // DG 1/2
+                recv.receiveDatagramBytes(sender, payload, proto, fromPort, toPort);
+            } else {
+                // DG 3
+                recv.receiveDatagramBytes(h, payload, proto, fromPort, toPort);
+            }
        } catch (IOException e) {
            _log.error("Error forwarding message to receiver", e);
            close();
--- a/apps/sam/java/src/net/i2p/sam/SAMv1Handler.java
+++ b/apps/sam/java/src/net/i2p/sam/SAMv1Handler.java
@@ -31,6 +31,7 @@ import net.i2p.data.Base64;
 import net.i2p.data.DataFormatException;
 import net.i2p.data.DataHelper;
 import net.i2p.data.Destination;
+import net.i2p.data.Hash;
 import net.i2p.util.Log;

 /**
@@ -277,7 +278,7 @@ class SAMv1Handler extends SAMHandler implements SAMRawReceiver, SAMDatagramRece
                    rawSession = new SAMRawSession(destKeystream, props, this);
                    rawSession.start();
                } else if (style.equals("DATAGRAM")) {
-                    datagramSession = new SAMDatagramSession(destKeystream, props,this);
+                    datagramSession = new SAMDatagramSession(destKeystream, props, this, 1);
                    datagramSession.start();
                } else if (style.equals("STREAM")) {
                    String dir = (String) props.remove("DIRECTION");
@@ -829,6 +830,11 @@ class SAMv1Handler extends SAMHandler implements SAMRawReceiver, SAMDatagramRece
        writeBytes(ByteBuffer.wrap(msg.toByteArray()));
    }

+    public void receiveDatagramBytes(Hash sender, byte data[], int proto,
+                                     int fromPort, int toPort) throws IOException {
+        throw new UnsupportedOperationException();
+    }
+
    public void stopDatagramReceiving() {
        if (_log.shouldLog(Log.DEBUG))
            _log.debug("stopDatagramReceiving() invoked");
--- a/apps/sam/java/src/net/i2p/sam/SAMv3DatagramSession.java
+++ b/apps/sam/java/src/net/i2p/sam/SAMv3DatagramSession.java
@@ -17,6 +17,7 @@ import net.i2p.client.I2PSessionException;
 import net.i2p.data.DataFormatException;
 import net.i2p.data.DataHelper;
 import net.i2p.data.Destination;
+import net.i2p.data.Hash;
 import net.i2p.util.Log;


@@ -36,15 +37,17 @@ class SAMv3DatagramSession extends SAMDatagramSession implements Session, SAMDat
 	 * Caller MUST call start().
 	 *
 	 * @param nick nickname of the session
+	 * @param version datagram version 1/2/3
 	 * @throws IOException
 	 * @throws DataFormatException
 	 * @throws I2PSessionException
 	 */
-	public SAMv3DatagramSession(String nick, SAMv3DatagramServer dgServer) 
+	public SAMv3DatagramSession(String nick, SAMv3DatagramServer dgServer, int version) 
 			throws IOException, DataFormatException, I2PSessionException, SAMException {
 		super(SAMv3Handler.sSessionsHash.get(nick).getDest(),
 				SAMv3Handler.sSessionsHash.get(nick).getProps(),
-				null  // to be replaced by this
+				null,  // to be replaced by this
+		                version
 				);
 		this.nick = nick;
 		this.recv = this;  // replacement
@@ -67,15 +70,16 @@ class SAMv3DatagramSession extends SAMDatagramSession implements Session, SAMDat
 	 * Caller MUST call start().
 	 *
 	 * @param nick nickname of the session
+	 * @param version datagram version 1/2/3
 	 * @throws IOException
 	 * @throws DataFormatException
 	 * @throws I2PSessionException
 	 * @since 0.9.25
 	 */
 	public SAMv3DatagramSession(String nick, Properties props, SAMv3Handler handler, I2PSession isess,
-	                            int listenPort, SAMv3DatagramServer dgServer) 
+	                            int listenPort, SAMv3DatagramServer dgServer, int version) 
 			throws IOException, DataFormatException, I2PSessionException {
-		super(isess, props, listenPort, null);  // to be replaced by this
+		super(isess, props, listenPort, null, version);  // to be replaced by this
 		this.nick = nick ;
 		this.recv = this ;  // replacement
 		this.server = dgServer;
@@ -88,22 +92,43 @@ class SAMv3DatagramSession extends SAMDatagramSession implements Session, SAMDat
 		if (this.clientAddress==null) {
 			this.handler.receiveDatagramBytes(sender, data, proto, fromPort, toPort);
 		} else {
-			StringBuilder buf = new StringBuilder(600);
-			buf.append(sender.toBase64());
-			if ((handler.verMajor == 3 && handler.verMinor >= 2) || handler.verMajor > 3) {
-				buf.append(" FROM_PORT=").append(fromPort).append(" TO_PORT=").append(toPort);
-			}
-			buf.append('\n');
-			String msg = buf.toString();
-			ByteBuffer msgBuf = ByteBuffer.allocate(msg.length()+data.length);
-			msgBuf.put(DataHelper.getASCII(msg));
-			msgBuf.put(data);
-			// not ByteBuffer to avoid Java 8/9 issues with flip()
-			((Buffer)msgBuf).flip();
-			this.server.send(this.clientAddress, msgBuf);
+			receiveDatagramBytes(sender.toBase64(), data, proto, fromPort, toPort);
 		}
 	}

+	/**
+	 * Only for Datagram3, where the sender Destination is not available, only the hash.
+	 * @since 0.9.68
+	 */
+	public void receiveDatagramBytes(Hash sender, byte[] data, int proto,
+	                                 int fromPort, int toPort) throws IOException {
+		if (this.clientAddress==null) {
+			this.handler.receiveDatagramBytes(sender, data, proto, fromPort, toPort);
+		} else {
+			receiveDatagramBytes(sender.toBase64(), data, proto, fromPort, toPort);
+		}
+	}
+
+	/**
+	 * @since 0.9.68 split out from above
+	 */
+	private void receiveDatagramBytes(String sender, byte[] data, int proto,
+	                                 int fromPort, int toPort) throws IOException {
+		StringBuilder buf = new StringBuilder(600);
+		buf.append(sender);
+		if ((handler.verMajor == 3 && handler.verMinor >= 2) || handler.verMajor > 3) {
+			buf.append(" FROM_PORT=").append(fromPort).append(" TO_PORT=").append(toPort);
+		}
+		buf.append('\n');
+		String msg = buf.toString();
+		ByteBuffer msgBuf = ByteBuffer.allocate(msg.length()+data.length);
+		msgBuf.put(DataHelper.getASCII(msg));
+		msgBuf.put(data);
+		// not ByteBuffer to avoid Java 8/9 issues with flip()
+		((Buffer)msgBuf).flip();
+		this.server.send(this.clientAddress, msgBuf);
+	}
+
 	public void stopDatagramReceiving() {
 	}
 }
--- a/apps/sam/java/src/net/i2p/sam/SAMv3Handler.java
+++ b/apps/sam/java/src/net/i2p/sam/SAMv3Handler.java
@@ -500,10 +500,20 @@ class SAMv3Handler extends SAMv1Handler
                                        rawSession = v3;
 					this.session = v3;
 					v3.start();
-				} else if (style.equals("DATAGRAM")) {
+				} else if (style.equals("DATAGRAM") ||
+					   style.equals("DATAGRAM2") ||
+					   style.equals("DATAGRAM3")) {
 					detector.start();
 					SAMv3DatagramServer dgs = bridge.getV3DatagramServer(props);
-					SAMv3DatagramSession v3 = new SAMv3DatagramSession(nick, dgs);
+					int v;
+					if (style.equals("DATAGRAM")) {
+						v = 1;
+					} else if (style.equals("DATAGRAM2")) {
+						v = 2;
+					} else {
+						v = 3;
+					}
+					SAMv3DatagramSession v3 = new SAMv3DatagramSession(nick, dgs, v);
 					datagramSession = v3;
 					this.session = v3;
 					v3.start();