Co:Z FTP-SSH Proxy

The Co:Z FTP-SSH Proxy architecture is designed to provide secure file transfer capabilities by integrating with existing FTP clients and SSH servers. The core components include the FTP Proxy Server, the SSH Client, and the Configuration Manager. The FTP Proxy Server acts as an intermediary, listening for incoming FTP connections on port 21.

It intercepts standard FTP commands such as `USER`, `PASS`, `CWD`, `CDUP`, `PWD`, `LIST`, `RETR`, `STOR`, `DELE`, `RNFR`, `RNTO`, and `QUIT`. Upon receiving a connection, the FTP Proxy Server establishes an SSH connection to the configured SSH server using the SSH Client. The SSH Client handles the secure tunnel creation, using the SSH protocol for encryption and authentication.

The SSH Client supports both password-based and public key authentication methods. The Configuration Manager is responsible for managing the configuration files, which contain settings such as the SSH server hostname or IP address, port number (typically 22), user credentials, and logging levels. The communication flow is as follows: An FTP client initiates a connection to the FTP Proxy Server.

The FTP Proxy Server then uses the SSH Client to establish a secure SSH connection to the destination server. All FTP commands and data are tunneled through this secure SSH connection. The product does not use any specific databases or storage mechanisms beyond the configuration files.

Network requirements include port 21 for FTP control and port 22 for SSH. The product's security model relies on the SSH server's access control mechanisms. The encryption uses the algorithms supported by the underlying SSH implementation, such as AES.

The product provides logging capabilities through system logs and the SSH server's logging features. There are no specific APIs exposed.