v0.3: 6-layer architecture complete

Layers:
  Layer 1: XDP/eBPF — TCP state machine, SYN throttle, blacklist, ringbuf
  Layer 2: PoW Challenge — SHA-256 hashcash, dynamic difficulty, constant-time verify
  Layer 3: Rust Core — HMAC handshake, rate limit, death code (existing)
  Layer 4: Velocity — Physics check, CAPTCHA, protocol verification
  Layer 5: Paper — Heartbeat, auto-registration (existing)
  Layer 6: Traffic Intel — EWMA, 168h profiling, reputation, alerts

Infra: XDP→Prometheus metrics, ClickHouse + Grafana dashboard, Docker Compose
Testing: 100-IP DDoS simulation, MHDDoS ref analysis, load test report
Fixes: VarInt sign extension UB, pure ACK deadlock, RST/FIN cleanup
Ref: MHDDoS, Sonar, LimboFilter, AtomGuard, Infrarust, MC-XDP-eBPF, PowGo

deploy/test/mclient.py

@@ -0,0 +1,73 @@
+#!/usr/bin/env python3
+"""Minecraft handshake client for testing Rampart."""
+
+import argparse
+import socket
+import struct
+import time
+
+
+def pack_varint(value):
+    buf = []
+    while True:
+        byte = value & 0x7F
+        value >>= 7
+        if value:
+            byte |= 0x80
+        buf.append(byte)
+        if not value:
+            break
+    return bytes(buf)
+
+
+def make_handshake(host, port, protocol=767):
+    packet = bytearray()
+    packet.extend(pack_varint(protocol))
+    packet.extend(pack_varint(len(host)))
+    packet.extend(host.encode())
+    packet.extend(struct.pack(">H", port))
+    packet.extend(pack_varint(2))
+    length = pack_varint(len(packet))
+    return length + bytes(packet)
+
+
+def main():
+    parser = argparse.ArgumentParser()
+    parser.add_argument("--target", default="localhost:25565")
+    parser.add_argument("--username", default="test_bot")
+    args = parser.parse_args()
+
+    host, port_str = args.target.split(":")
+    port = int(port_str)
+
+    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+    sock.settimeout(10)
+    sock.connect((host, port))
+    sock.sendall(make_handshake(host, port))
+
+    data = sock.recv(4096)
+    if data:
+        print(f"Got response: {data.hex()}")
+        # If PoW challenge -> receive challenge, solve, send nonce
+        if b"challenge" in data:
+            print("PoW challenge received")
+            challenge = data.decode().strip()
+            for nonce in range(1000000):
+                import hashlib
+
+                h = hashlib.sha256(f"{challenge}{nonce}".encode()).hexdigest()
+                if h.startswith("0000"):
+                    sock.sendall(str(nonce).encode())
+                    resp = sock.recv(4096)
+                    print(f"PoW ok, handshake: {resp.hex()}")
+                    break
+        else:
+            print(f"Handshake response: {data.hex()}")
+    else:
+        print("No response (blocked)")
+
+    sock.close()
+
+
+if __name__ == "__main__":
+    main()