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A main program (executable JAR) that will listen to port 29998. At first, it can only answer that it is an Envoy (a limited agent). The only function it supports is installing a -runpath. It will then create a framework + agent and transfer the connection to the just installed agent who will then install the bundles. This JAR is a main command for JPM called bndremote. In JPM, it will start up with debug enabled. This JAR does some highly complicated class loading wizardy to ensure that it does not enforce any constraints on the -runpath.

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package aQute.lib.io;

import static java.util.Objects.requireNonNull;

import java.io.EOFException;
import java.io.IOException;
import java.io.InputStream;

public class LimitedInputStream extends InputStream {
	private final InputStream	in;
	private long				remaining;
	private long				marked;

	public LimitedInputStream(InputStream in, int size) {
		this.in = requireNonNull(in);
		this.remaining = size;
		this.marked = size;
		if (size < 0) {
			throw new IllegalArgumentException("size must be non-negative");
		}
	}

	private void consume(long n) throws IOException {
		if (n - remaining > 0L) {
			throw new EOFException("request to read more bytes than available");
		}
		remaining -= n;
	}

	private boolean hasRemaining() {
		return remaining > 0L;
	}

	private long ranged(long n) {
		if (n <= 0L) {
			return 0L;
		}
		return Math.min(n, remaining);
	}

	@Override
	public int read() throws IOException {
		if (hasRemaining()) {
			int read = in.read();
			consume(Byte.BYTES);
			return read;
		}
		eof();
		return -1;
	}

	@Override
	public int available() throws IOException {
		return (int) ranged(in.available());
	}

	@Override
	public void close() throws IOException {
		remaining = 0L;
		eof();
		in.close();
	}

	protected void eof() {}

	@Override
	public synchronized void mark(int readlimit) {
		in.mark((int) ranged(readlimit));
		marked = remaining;
	}

	@Override
	public boolean markSupported() {
		return in.markSupported();
	}

	@Override
	public int read(byte[] b, int off, int len) throws IOException {
		if (hasRemaining()) {
			int read = in.read(b, off, (int) ranged(len));
			consume(read);
			return read;
		}
		eof();
		return -1;
	}

	@Override
	public int read(byte[] b) throws IOException {
		return read(b, 0, b.length);
	}

	@Override
	public synchronized void reset() throws IOException {
		if (!in.markSupported()) {
			throw new IOException("mark/reset not supported");
		}
		in.reset();
		remaining = marked;
	}

	@Override
	public long skip(long n) throws IOException {
		long skipped = in.skip(ranged(n));
		consume(skipped);
		return skipped;
	}
}