ftpserver

type AnswerCommand struct {
	Code    int
	Message string
}

type ClientContext interface {
	// Path provides the path of the current connection
	Path() string

	// SetPath sets the path of the current connection.
	// This method is useful to set a start directory, you should use it before returning a successful
	// authentication response from your driver implementation.
	// Calling this method after the authentication step could lead to undefined behavior
	SetPath(value string)

	// SetListPath allows to change the path for the last LIST/NLST request.
	// This method is useful if the driver expands wildcards and so the returned results
	// refer to a path different from the requested one.
	// The value must be cleaned using path.Clean
	SetListPath(value string)

	// SetDebug activates the debugging of this connection commands
	SetDebug(debug bool)

	// Debug returns the current debugging status of this connection commands
	Debug() bool

	// Client's ID on the server
	ID() uint32

	// Client's address
	RemoteAddr() net.Addr

	// Servers's address
	LocalAddr() net.Addr

	// Client's version can be empty
	GetClientVersion() string

	// Close closes the connection and disconnects the client.
	Close() error

	// HasTLSForControl returns true if the control connection is over TLS
	HasTLSForControl() bool

	// HasTLSForTransfers returns true if the transfer connection is over TLS
	HasTLSForTransfers() bool

	// GetLastCommand returns the last received command
	GetLastCommand() string

	// GetLastDataChannel returns the last data channel mode
	GetLastDataChannel() DataChannel

	// SetTLSRequirement sets the TLS requirement to respect on a per-client basis.
	// The requirement is checked when the client issues the "USER" command,
	// after executing the MainDriverExtensionUserVerifier extension, and
	// before opening transfer connections.
	// Supported values: ClearOrEncrypted, MandatoryEncryption.
	// If you want to enforce the same requirement for all
	// clients, use the TLSRequired parameter defined in server settings instead
	SetTLSRequirement(requirement TLSRequirement) error

	// SetExtra allows to set application specific data
	SetExtra(extra any)

	// Extra returns application specific data set using SetExtra
	Extra() any
}

type ClientDriver interface {
	afero.Fs
}

type ClientDriverExtensionAllocate interface {
	// AllocateSpace reserves the space necessary to upload files
	AllocateSpace(size int) error
}

type ClientDriverExtensionAvailableSpace interface {
	GetAvailableSpace(dirName string) (int64, error)
}

type ClientDriverExtensionFileList interface {
	// ReadDir reads the directory named by name and return a list of directory entries.
	ReadDir(name string) ([]os.FileInfo, error)
}

type ClientDriverExtensionHasher interface {
	ComputeHash(name string, algo HASHAlgo, startOffset, endOffset int64) (string, error)
}

type ClientDriverExtensionRemoveDir interface {
	RemoveDir(name string) error
}

type ClientDriverExtensionSite interface {
	Site(param string) *AnswerCommand
}

type ClientDriverExtensionSymlink interface {
	// Symlink creates a symlink
	Symlink(oldname, newname string) error
}

type ClientDriverExtentionFileTransfer interface {
	// GetHandle return an handle to upload or download a file based on flags:
	// os.O_RDONLY indicates a download
	// os.O_WRONLY indicates an upload and can be combined with os.O_APPEND (resume) or
	// os.O_CREATE (upload to new file/truncate)
	//
	// offset is the argument of a previous REST command, if any, or 0
	GetHandle(name string, flags int, offset int64) (FileTransfer, error)
}

type CommandDescription struct {
	Open            bool                               // Open to clients without auth
	TransferRelated bool                               // This is a command that can open a transfer connection
	SpecialAction   bool                               // Command to handle even if there is a transfer in progress
	Fn              func(*clientHandler, string) error // Function to handle it
}

type DataChannel int8

type DataConnectionRequirement int8

type DriverError struct {
	// contains filtered or unexported fields
}

type FileAccessError struct {
	// contains filtered or unexported fields
}

type FileTransfer interface {
	io.Reader
	io.Writer
	io.Seeker
	io.Closer
}

type FileTransferError interface {
	TransferError(err error)
}

type Flusher interface {
	Flush() error
}

type FtpServer struct {
	Logger *slog.Logger // Structured logger (log/slog)
	// contains filtered or unexported fields
}

type HASHAlgo int8

type MainDriver interface {
	// GetSettings returns some general settings around the server setup
	GetSettings() (*Settings, error)

	// ClientConnected is called to send the very first welcome message
	ClientConnected(cc ClientContext) (string, error)

	// ClientDisconnected is called when the user disconnects, even if he never authenticated
	ClientDisconnected(cc ClientContext)

	// AuthUser authenticates the user and selects an handling driver
	AuthUser(cc ClientContext, user, pass string) (ClientDriver, error)

	// GetTLSConfig returns a TLS Certificate to use
	// The certificate could frequently change if we use something like "let's encrypt"
	GetTLSConfig() (*tls.Config, error)
}

type MainDriverExtensionPassiveWrapper interface {
	// WrapPassiveListener is called after creating the listener for passive
	// data connections.
	// You can wrap the passed listener or just return it unmodified.
	// Returning an error will cause the passive connection to fail
	WrapPassiveListener(listener net.Listener) (net.Listener, error)
}

type MainDriverExtensionPostAuthMessage interface {
	// PostAuthMessage is called after the authentication
	PostAuthMessage(cc ClientContext, user string, authErr error) string
}

type MainDriverExtensionQuitMessage interface {
	// QuitMessage returns the message to display when the user quits the server
	QuitMessage() string
}

type MainDriverExtensionTLSVerifier interface {
	// VerifyConnection is called when receiving the "USER" command.
	// If it returns a non-nil error, the client will receive a 530 error and it will be disconnected.
	// If it returns a non-nil ClientDriver and a nil error the client will be authenticated.
	// If it returns a nil ClientDriver and a nil error the user password is required
	VerifyConnection(cc ClientContext, user string, tlsConn *tls.Conn) (ClientDriver, error)
}

type MainDriverExtensionUserVerifier interface {
	// PreAuthUser is called when receiving the "USER" command before proceeding with any other checks
	// If it returns a non-nil error, the client will receive a 530 error and be disconnected.
	PreAuthUser(cc ClientContext, user string) error
}

type NetworkError struct {
	// contains filtered or unexported fields
}

type PasvPortGetter interface {
	// FetchNext returns the exposed one, the listened one and whether succeeded
	FetchNext() (int, int, bool)
	// NumberAttempts returns maximum number of attempts on finding an available passive transfer port
	NumberAttempts() int
}

type PortMappingRange struct {
	ExposedStart  int
	ListenedStart int
	Count         int
}

type PortRange struct {
	Start int // Range start
	End   int // Range end
}

type PublicIPResolver func(ClientContext) (string, error)

type Settings struct {
	Listener                 net.Listener     // (Optional) To provide an already initialized listener
	ListenAddr               string           // Listening address
	PublicHost               string           // Public IP to expose (only an IP address is accepted at this stage)
	Banner                   string           // Banner to use in server status response
	PassiveTransferPortRange PasvPortGetter   // (Optional) Port Mapping for data connections. Random if not specified
	PublicIPResolver         PublicIPResolver // (Optional) To fetch a public IP lookup
	IdleTimeout              int              // Maximum inactivity time before disconnecting (#58)
	ConnectionTimeout        int              // Maximum time to establish passive or active transfer connections
	ActiveTransferPortNon20  bool             // Do not impose the port 20 for active data transfer (#88, RFC 1579)
	DisableMLSD              bool             // Disable MLSD support
	DisableMLST              bool             // Disable MLST support
	DisableMFMT              bool             // Disable MFMT support (modify file mtime)
	TLSRequired              TLSRequirement   // defines the TLS mode
	DisableLISTArgs          bool             // Disable ls like options (-a,-la etc.) for directory listing
	DisableSite              bool             // Disable SITE command
	DisableActiveMode        bool             // Disable Active FTP
	EnableHASH               bool             // Enable support for calculating hash value of files
	DisableSTAT              bool             // Disable Server STATUS, STAT on files and directories will still work
	DisableSYST              bool             // Disable SYST
	EnableCOMB               bool             // Enable COMB support
	DeflateCompressionLevel  int              // Deflate compression level (1-9)
	DefaultTransferType      TransferType     // Transfer type to use if the client don't send the TYPE command
	// ActiveConnectionsCheck defines the security requirements for active connections
	ActiveConnectionsCheck DataConnectionRequirement
	// PasvConnectionsCheck defines the security requirements for passive connections
	PasvConnectionsCheck DataConnectionRequirement
}

type TLSRequirement int8

type TransferFinalizer interface {
	FinalizeTransfer() error
}

type TransferMode int8

type TransferType int8