When the slicer and printer are on different VLANs, Bambu Studio could
not send prints through the proxy because the printer's real IP leaked
through MQTT payloads, the bind protocol forwarded the real printer's
identity, the port 6000 file transfer tunnel was not proxied, and FTP
data connections raced the TLS handshake on zero-byte uploads.
- Rewrite IP addresses in MQTT PUBLISH payloads (string + integer)
with proper packet framing and cross-chunk buffering
- Respond to bind/detect with VP identity via BindServer
- Add TLS proxy for port 6000 (file transfer tunnel)
- Buffer slicer FTP data during printer connection setup
- Advertise configured VP name in SSDP proxy
- Add cross-subnet SSDP wildcard listener for VPN setups
- Register UserEmailPreference model in models/__init__.py
- Add 11 unit tests for MQTT rewrite, IP conversion, SSDP name
When running multiple virtual printers with different access codes on
separate bind IPs, FTP connections were always routed to the wrong VP.
Root cause: the iptables REDIRECT rule (990→9990) rewrites the
destination IP to the incoming interface's primary address. With Linux's
weak host model (arp_filter=0), packets for secondary IPs arrive on the
primary interface, and REDIRECT sends them all to the first VP's FTP
server. MQTT was unaffected because port 8883 had no redirect.
Fix: FTP server now binds directly to port 990 (standard implicit FTPS),
eliminating the iptables redirect entirely. Requires CAP_NET_BIND_SERVICE
(already set in the systemd service file and Docker image).
Also removed a global asyncio set_exception_handler() in the MQTT server
that was overwritten by each VP instance, causing spurious "Unhandled
exception in client_connected_cb" errors on startup.
Changes:
- FTP_PORT: 9990 → 990 (ftp_server.py)
- Removed set_exception_handler() from MQTT server
- Updated Dockerfile, docker-compose.yml port mappings
- Deprecated --redirect-990 in install script
- Updated wiki: removed iptables instructions for all platforms
- Added migration guide (docs/migration-vp-ftp-port.md)
- Added unit tests for port constant and no-global-state invariant
The remote_interface_ip setting only worked in proxy mode but was
completely ignored in server modes (immediate/review/print_queue).
Users with multiple NICs (LAN + Tailscale, Docker bridges) got wrong
auto-detected IP in SSDP broadcasts and TLS certificates.
Enable Bambu Studio on a remote network to print through BamBuddy
acting as a TLS-terminating proxy for both MQTT and FTP connections.
- Add TLSProxy base class and FTPTLSProxy with PASV response rewriting,
EPSV→PASV translation, PROT P/C tracking, and one-shot data proxies
- Add SlicerProxyManager to coordinate per-slicer MQTT + FTP proxy pairs
- Support additional SAN IPs in certificate generation for proxy mode
- Broadcast SSDP on LAN B so slicers discover the proxy as a printer
- Narrow FTP passive port range to 50000-50100 with retry logic
- Expose proxy ports (8883, 9990, 50000-50100) in Dockerfile
- Document passive port range in docker-compose.yml
- SSDP proxy for cross-network setups: select slicer network interface for automatic printer discovery via SSDP relay
- FTP proxy now listens on privileged port 990 (matching Bambu Studio expectations) instead of 9990
- For systemd: requires `AmbientCapabilities=CAP_NET_BIND_SERVICE` capability
- Automatic directory permission checking at startup with clear error messages for Docker/bare metal
- Virtual printer appears in Bambu Studio/Orca Slicer via SSDP discovery
- Secure TLS/MQTT communication with auto-generated certificates
- Queue mode (pending uploads) or auto-start mode
- Configurable access code for authentication
- Docker support with network_mode: host and certificate persistence
- Fix backup/restore for virtual printer settings (auto-save no longer overwrites)
maziggy