FTP
[User Protocols]

Collaboration diagram for FTP:

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Detailed Description

File transfer protocol.

Note, that FTP servers don't make much sense without a file system providing write access. Right now, FTP had been tested with the PNUT file system only.

Internet File Transfer Protocol Server.

Data Structures
struct	FTPSESSION
	FTP session information structure. More...
FTP Server Configuration
The Nut/OS Configurator may be used to override the default values.
#define	FTP_MAX_CMDBUF   128
	UDP port of DHCP server.
FTP Server Configuration
The Nut/OS Configurator may be used to override the default values.
#define	FTP_ROOTPATH   "PNUT:"
	Default FTP root path.
#define	FTP_DATA_PORT   20
	Default data port.
Functions
int	NutFtpRespondOk (FTPSESSION *session, int code)
	Send a positive response.
int	NutFtpRespondBad (FTPSESSION *session, int code)
	Send a negative response.
int	NutFtpSendMode (FTPSESSION *session, int binary)
	Send a response including the specified transfer mode.
char *	CreateFullPathName (char *root, char *work, char *path)
	Create an absolute path name.
TCPSOCKET *	NutFtpDataConnect (FTPSESSION *session)
	Establish an FTP connection for data transfer.
int	NutRegisterFtpRoot (CONST char *path)
	Register the FTP server's root directory.
int	NutRegisterFtpUser (CONST char *user, CONST char *pass)
	Register an FTP user.
FTPSESSION *	NutFtpOpenSession (TCPSOCKET *sock)
	Open an FTP server session.
void	NutFtpCloseSession (FTPSESSION *session)
	Close an FTP server session.
int	NutFtpProcessCwd (FTPSESSION *session, char *path)
	Process an FTP client's CWD command.
int	NutFtpProcessDelete (FTPSESSION *session, char *path)
	Process an FTP client's DELE command.
int	NutFtpTransferFile (FTPSESSION *session, char *path, int mode)
	Transfer a file to or from the FTP client.
int	NutFtpTransferDirectory (FTPSESSION *session, char *path)
	Process an FTP client's LIST or NLST command.
int	NutFtpProcessMkd (FTPSESSION *session, char *path)
	Process an FTP client's MKD command.
int	NutFtpProcessPass (FTPSESSION *session, char *pass)
	Process an FTP client's PASS command.
int	NutFtpProcessPassiv (FTPSESSION *session)
	Process an FTP client's PASV command.
int	NutFtpProcessPort (FTPSESSION *session, char *args)
	Process an FTP client's PORT command.
int	NutFtpProcessPwd (FTPSESSION *session)
	Process an FTP client's PWD command.
int	NutFtpProcessRmd (FTPSESSION *session, char *path)
	Process an FTP client's RMD command.
int	NutFtpProcessSystem (FTPSESSION *session)
	Process an FTP client's SYST command.
int	NutFtpProcessType (FTPSESSION *session, char *typecode)
	Process an FTP client's TYPE command.
int	NutFtpProcessUser (FTPSESSION *session, char *user)
	Process an FTP client's USER command.
int	NutFtpProcessRequest (FTPSESSION *session, char *request)
	Process an FTP request.
int	NutFtpServerSession (TCPSOCKET *sock)
	Process an FTP sever session.

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Function Documentation

int NutFtpRespondOk (  FTPSESSION *  session, int  code )

Send a positive response. Parameters: session  Pointer to an FTPSESSION structure, obtained by a previous call to NutFtpOpenSession(). code  Response code. Returns: -1 if the session ended. Otherwise 0 is returned.

int NutFtpRespondBad (  FTPSESSION *  session, int  code )

Send a negative response. Parameters: session  Pointer to an FTPSESSION structure, obtained by a previous call to NutFtpOpenSession(). code  Response code. Returns: -1 if the session ended. Otherwise 0 is returned.

int NutFtpSendMode (  FTPSESSION *  session, int  binary )

Send a response including the specified transfer mode. Parameters: session  Pointer to an FTPSESSION structure, obtained by a previous call to NutFtpOpenSession(). binary  0 indicates ASCII transfer mode. Returns: -1 if the session ended. Otherwise 0 is returned.

char* CreateFullPathName (  char *  root, char *  work, char *  path )

Create an absolute path name. Combines an absolute directory path with a relative path name to a full absolute path name. The absolute directory is split into two parts, the root and the current work directory. The resulting path will never be above the specified root. Parameters: root  Non-empty absolute root directory path including the device name, but without a trailing slash. work  Absolute work directory path below root including a leading, but without a trailing slash. This path is ignored if the relative path starts with a slash. path  Relative path name of a file or directory without any trailing slash. Returns: Pointer to the resulting path name. The buffer for this name is allocated from heap memory. The caller is responsible for freeing it. In case of an error, a NULL pointer is returned.

TCPSOCKET* NutFtpDataConnect (  FTPSESSION *  session  )

Establish an FTP connection for data transfer. Parameters: session  Pointer to an FTPSESSION structure, obtained by a previous call to NutFtpOpenSession(). Returns: Socket descriptor of the newly created data connection or 0 if we were unable to establish the connection.

int NutRegisterFtpRoot (  CONST char *  path  )

Register the FTP server's root directory. Only one root directory is supported. Subsequent calls will override previous settings. Parameters: path  Path name of the root directory. Must include the device name followed by a colon followed by an absolute directory path. May be set to NULL for the default FTP_ROOTPATH. Returns: 0 on success, -1 otherwise.

int NutRegisterFtpUser (  CONST char *  user, CONST char *  pass )

Register an FTP user. Only one username/password pair is supported. Subsequent calls will override previous settings. Warning: Not successfully registering any will make file systems accessible by anyone. Parameters: user  User's name. pass  Uncrypted password for the specified user. Returns: 0 on success. -1 is returned on failures, in which case no protection may be assumed.

FTPSESSION* NutFtpOpenSession (  TCPSOCKET *  sock  )

Open an FTP server session. Parameters: sock  Socket of an established TCP connection. Returns: Pointer to an FTPSESSION structure, which can be used in subsequent API calls. NULL is returned in case of any error.

void NutFtpCloseSession (  FTPSESSION *  session  )

Close an FTP server session. Parameters: session  Pointer to an FTPSESSION structure, obtained by a previous call to NutFtpOpenSession().

int NutFtpProcessCwd (  FTPSESSION *  session, char *  path )

Process an FTP client's CWD command. Parameters: session  Pointer to an FTPSESSION structure, obtained by a previous call to NutFtpOpenSession(). path  Full absolute path name of the directory. Returns: 0 if the command has been processed or -1 if the session has been aborted.

int NutFtpProcessDelete (  FTPSESSION *  session, char *  path )

Process an FTP client's DELE command. Causes the specified file to be deleted. Parameters: session  Pointer to an FTPSESSION structure, obtained by a previous call to NutFtpOpenSession(). path  Full absolute path name of the file. Returns: 0 if the command has been processed or -1 if the session has been aborted.

int NutFtpTransferFile (  FTPSESSION *  session, char *  path, int  mode )

Transfer a file to or from the FTP client. Parameters: session  Pointer to an FTPSESSION structure, obtained by a previous call to NutFtpOpenSession(). path  Full absolute path name of the file. mode  If set to zero, the server will accept the data transferred via the data connection and to store the data as a file. If the file exists, then its contents will be replaced by the data being transferred. A new file is created, if the file does not already exist. If this parameter is not equal zero, then the server will transfer a copy of the specified file. Returns: 0 if the command has been processed or -1 if the session has been aborted.

int NutFtpTransferDirectory (  FTPSESSION *  session, char *  path )

Process an FTP client's LIST or NLST command. Causes a directory listing to be sent to the client. Parameters: session  Pointer to an FTPSESSION structure, obtained by a previous call to NutFtpOpenSession(). path  Full absolute path name of the directory. Returns: 0 if the command has been processed or -1 if the session has been aborted.

int NutFtpProcessMkd (  FTPSESSION *  session, char *  path )

Process an FTP client's MKD command. Causes the specified directory to be created. Parameters: session  Pointer to an FTPSESSION structure, obtained by a previous call to NutFtpOpenSession(). path  Full absolute path name of the directory. Returns: 0 if the command has been processed or -1 if the session has been aborted.

int NutFtpProcessPass (  FTPSESSION *  session, char *  pass )

Process an FTP client's PASS command. Only one login per session is accepted. Parameters: session  Pointer to an FTPSESSION structure, obtained by a previous call to NutFtpOpenSession(). pass  Password. Returns: 0 if the command has been processed or -1 if the session has been aborted.

int NutFtpProcessPassiv (  FTPSESSION *  session  )

Process an FTP client's PASV command. This command requests the server to listen on a data port and to wait for a connection rather than initiate one upon receipt of a transfer command. Parameters: session  Pointer to an FTPSESSION structure, obtained by a previous call to NutFtpOpenSession(). Returns: 0 if the command has been processed or -1 if the session has been aborted.

int NutFtpProcessPort (  FTPSESSION *  session, char *  args )

Process an FTP client's PORT command. Parameters: session  Pointer to an FTPSESSION structure, obtained by a previous call to NutFtpOpenSession(). args  Command argument, which is the concatenation of the 32-bit internet host address and a 16-bit TCP port address. This address information is broken into 8-bit fields and the value of each field is transmitted as a decimal number. Returns: 0 if the command has been processed or -1 if the session has been aborted.

int NutFtpProcessPwd (  FTPSESSION *  session  )

Process an FTP client's PWD command. Causes the name of the current working directory to be returned in the reply. Parameters: session  Pointer to an FTPSESSION structure, obtained by a previous call to NutFtpOpenSession(). Returns: 0 if the command has been processed or -1 if the session has been aborted.

int NutFtpProcessRmd (  FTPSESSION *  session, char *  path )

Process an FTP client's RMD command. Causes the specified directory to be removed. Parameters: session  Pointer to an FTPSESSION structure, obtained by a previous call to NutFtpOpenSession(). path  Full absolute path name of the directory. Returns: 0 if the command has been processed or -1 if the session has been aborted.

int NutFtpProcessSystem (  FTPSESSION *  session  )

Process an FTP client's SYST command. Parameters: session  Pointer to an FTPSESSION structure, obtained by a previous call to NutFtpOpenSession(). Returns: 0 if the command has been processed or -1 if the session has been aborted.

int NutFtpProcessType (  FTPSESSION *  session, char *  typecode )

Process an FTP client's TYPE command. The type is not fully checked. Any argument starting with the letters 'A' or 'a' will switch the transfer mode to ASCII. Otherwise binary mode is set. Parameters: session  Pointer to an FTPSESSION structure, obtained by a previous call to NutFtpOpenSession(). typecode  Command arguments. Returns: 0 if the command has been processed or -1 if the session has been aborted.

int NutFtpProcessUser (  FTPSESSION *  session, char *  user )

Process an FTP client's USER command. Only one login per session is accepted. Parameters: session  Pointer to an FTPSESSION structure, obtained by a previous call to NutFtpOpenSession(). user  User name. Returns: 0 if the command has been processed or -1 if the session has been aborted.

int NutFtpProcessRequest (  FTPSESSION *  session, char *  request )

Process an FTP request. This routine implements the protocol interpreter of the FTP server. Parameters: session  Pointer to an FTPSESSION structure, obtained by a previous call to NutFtpOpenSession(). request  Request string. Returns: -1 if the session ended. Otherwise 0 is returned.

int NutFtpServerSession (  TCPSOCKET *  sock  )

Process an FTP sever session. Processes FTP requests on an established connection with an FTP client. This routine completely implements an FTP server except TCP connect and disconnect. For file transfers, the same maximum segment size and timeouts as set for this socket will be used for the data connection. Parameters: sock  Socket of an established TCP connection. Returns: 0 if the session ended successfully or -1 if the session has been aborted.

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