Secure Tunnel Client

Secure Tunnel Client is a lightweight Linux alternative to SoftEther VPN Client
workflows for user-space TLS-encrypted TCP port-forwarding, SOCKS5-over-TLS
tunneling, and Linux network interface monitoring.

Features (100% real sockets and kernel telemetry):
- SQLite-backed TLS Tunnel Profiles supporting both Client Mode and Server Mode
- TLS 1.2 / TLS 1.3 encryption using Python ssl.SSLContext with X.509 certificate
generation (RSA-2048 PEM) or custom PEM certificate/key files
- Optional pre-shared token authentication and SHA-256 peer certificate pinning
- TCP Port-Forwarding over TLS and built-in RFC 1928 SOCKS5-over-TLS listener
- Real-time TLS cipher negotiation inspector, peer SHA-256 fingerprint, and
encrypted tunnel RTT ping probe
- Multi-port forward rules manager, live stream monitor, CSV export, and live
measured TX/RX throughput graph
- System Network & Tunnel Interfaces Inspector reading /sys/class/net,
/proc/net/dev, /proc/net/if_inet6, ioctl IPv4 addresses, and /proc/net/route

Honest scope & limitations:
Operates strictly as a user-space TLS-encrypted TCP port-forwarder and
SOCKS5-over-TLS proxy tunnel. It does NOT create a kernel Layer-2/Layer-3
virtual network adapter (TUN/TAP), does not modify system-wide routing tables,
and does not tunnel raw UDP or ICMP packets.

Disclaimer: This project is an independent open-source tool and is not
affiliated with, sponsored by, or endorsed by SoftEther Corporation.

Support development: https://buymeacoffee.com/thanhnv128b