MODULE TFTPDEF IDENT "TFTPDEF-1-X";
/*++
/*Facility:
/*   TFTP Server Client
/* 
/* Abstract:
/*   An interface module defined TFTP primitives, constants, this story is based on
/*	RFC1350 (THE TFTP PROTOCOL (REVISION 2))
/*	ftp://ftp.rfc-editor.org/in-notes/rfc1350.txt
/* 
/* Author:
/*   Ruslan R. Laishev
/* 
/* Creation Date: 24-MAY-2004
/* 
/* Modification History:
/*--

/*
/**++
/**
/**	TFTP modes of transfer
/**
/**--
/*

CONSTANT	(
		NETASCII,		/* This is
				/* ascii as defined in "USA Standard Code for Information Interchange"
				/* [1] with the modifications specified in "Telnet Protocol
				/* Specification" [3].)  Note that it is 8 bit ascii.
		OCTET		/* octet (This replaces the "binary" mode
				/* of previous versions of this document.) raw 8 bit bytes;
		)
  	EQUALS 1 INCREMENT 1 PREFIX TFTP__$;


CONSTANT	PORT	EQUALS 69 PREFIX TFTP__$;

/*
/**++
/**
/**	TFTP primitives
/**
/*
/*   Type   Op #     Format without header
/*
/*          2 bytes    string   1 byte     string   1 byte
/*          -----------------------------------------------
/*   RRQ/  | 01/02 |  Filename  |   0  |    Mode    |   0  |
/*   WRQ    -----------------------------------------------
/*          2 bytes    2 bytes       n bytes
/*          ---------------------------------
/*   DATA  | 03    |   Block #  |    Data    |
/*          ---------------------------------
/*          2 bytes    2 bytes
/*          -------------------
/*   ACK   | 04    |   Block #  |
/*          --------------------
/*          2 bytes  2 bytes        string    1 byte
/*          ----------------------------------------
/*   ERROR | 05    |  ErrorCode |   ErrMsg   |   0  |
/*          ----------------------------------------
/**--

CONSTANT	(
		RRQ,		/* 1     Read request (RRQ)
		WRQ,		/* 2     Write request (WRQ)
		DATA,		/* 3     Data (DATA)
		ACK,		/* 4     Acknowledgment (ACK)
		ERROR		/* 5     Error (ERROR)
		)
  	EQUALS 1 INCREMENT 1 PREFIX TFTP_OPC$;



AGGREGATE tftp_pdu STRUCTURE PREFIX tftp_pdu$;
		opcode	WORD UNSIGNED;			/* field which indicates
							/* the packet's type (e.g., DATA, ERROR, etc.)  These opcodes and  the
							/* formats of  the various types of packets are discussed further in the
							/* section on TFTP packets.

		req	UNION;
			xrq	STRUCTURE;
			args	BYTE UNSIGNED DIMENSION 510;
			END xrq;

			data	STRUCTURE;
			lbn	WORD UNSIGNED;
			data	BYTE UNSIGNED DIMENSION 512;
			END	data;

			ack	STRUCTURE;
			lbn     WORD UNSIGNED;
			END	ack;

			error	STRUCTURE;
			code	WORD UNSIGNED;
			msg	BYTE UNSIGNED DIMENSION 510;
			END	error;
   		END	req;
END	tftp_pdu;
			
END_MODULE TFTPDEF;