1 | # SPDX-License-Identifier: BSD-2-Clause |
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2 | '''The TFTP Server handles a read only TFTP session.''' |
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3 | |
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4 | # Copyright (C) 2020 Chris Johns (chrisj@rtems.org) |
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5 | # |
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6 | # Redistribution and use in source and binary forms, with or without |
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7 | # modification, are permitted provided that the following conditions |
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8 | # are met: |
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9 | # 1. Redistributions of source code must retain the above copyright |
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10 | # notice, this list of conditions and the following disclaimer. |
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11 | # 2. Redistributions in binary form must reproduce the above copyright |
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12 | # notice, this list of conditions and the following disclaimer in the |
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13 | # documentation and/or other materials provided with the distribution. |
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14 | # |
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15 | # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
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16 | # AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
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17 | # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
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18 | # ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE |
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19 | # LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
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20 | # CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
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21 | # SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
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22 | # INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
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23 | # CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
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24 | # ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
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25 | # POSSIBILITY OF SUCH DAMAGE. |
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26 | |
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27 | from __future__ import print_function |
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28 | |
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29 | import argparse |
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30 | import os |
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31 | import socket |
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32 | import sys |
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33 | import time |
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34 | import threading |
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35 | |
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36 | try: |
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37 | import socketserver |
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38 | except ImportError: |
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39 | import SocketServer as socketserver |
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40 | |
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41 | from rtemstoolkit import error |
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42 | from rtemstoolkit import log |
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43 | from rtemstoolkit import version |
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44 | |
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45 | |
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46 | class tftp_session(object): |
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47 | '''Handle the TFTP session packets initiated on the TFTP port (69). |
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48 | ''' |
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49 | # pylint: disable=useless-object-inheritance |
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50 | # pylint: disable=too-many-instance-attributes |
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51 | |
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52 | opcodes = ['nul', 'RRQ', 'WRQ', 'DATA', 'ACK', 'ERROR', 'OACK'] |
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53 | |
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54 | OP_RRQ = 1 |
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55 | OP_WRQ = 2 |
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56 | OP_DATA = 3 |
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57 | OP_ACK = 4 |
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58 | OP_ERROR = 5 |
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59 | OP_OACK = 6 |
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60 | |
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61 | E_NOT_DEFINED = 0 |
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62 | E_FILE_NOT_FOUND = 1 |
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63 | E_ACCESS_VIOLATION = 2 |
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64 | E_DISK_FULL = 3 |
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65 | E_ILLEGAL_TFTP_OP = 4 |
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66 | E_UKNOWN_TID = 5 |
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67 | E_FILE_ALREADY_EXISTS = 6 |
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68 | E_NO_SUCH_USER = 7 |
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69 | E_NO_ERROR = 10 |
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70 | |
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71 | def __init__(self, host, port, base, forced_file, reader=None): |
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72 | # pylint: disable=too-many-arguments |
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73 | self.host = host |
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74 | self.port = port |
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75 | self.base = base |
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76 | self.forced_file = forced_file |
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77 | if reader is None: |
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78 | self.data_reader = self._file_reader |
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79 | else: |
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80 | self.data_reader = reader |
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81 | self.filein = None |
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82 | self.resends_limit = 5 |
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83 | # These are here to shut pylint up |
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84 | self.block = 0 |
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85 | self.last_data = None |
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86 | self.block_size = 512 |
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87 | self.timeout = 0 |
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88 | self.resends = 0 |
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89 | self.finished = False |
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90 | self.filename = None |
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91 | self._reinit() |
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92 | |
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93 | def _reinit(self): |
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94 | '''Reinitialise all the class variables used by the protocol.''' |
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95 | if self.filein is not None: |
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96 | self.filein.close() |
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97 | self.filein = None |
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98 | self.block = 0 |
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99 | self.last_data = None |
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100 | self.block_size = 512 |
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101 | self.timeout = 0 |
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102 | self.resends = 0 |
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103 | self.finished = False |
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104 | self.filename = None |
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105 | |
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106 | def _file_reader(self, command, **kwargs): |
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107 | '''The default file reader if the user does not provide one. |
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108 | |
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109 | The call returns a two element tuple where the first element |
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110 | is an error code, and the second element is data if the error |
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111 | code is 0 else it is an error message. |
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112 | ''' |
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113 | # pylint: disable=too-many-return-statements |
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114 | if command == 'open': |
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115 | if 'filename' not in kwargs: |
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116 | raise error.general('tftp-reader: invalid open: no filename') |
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117 | filename = kwargs['filename'] |
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118 | try: |
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119 | self.filein = open(filename, 'rb') |
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120 | filesize = os.stat(filename).st_size |
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121 | except FileNotFoundError: |
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122 | return self.E_FILE_NOT_FOUND, 'file not found (%s)' % ( |
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123 | filename) |
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124 | except PermissionError: |
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125 | return self.E_ACCESS_VIOLATION, 'access violation' |
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126 | except IOError as ioe: |
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127 | return self.E_NOT_DEFINED, str(ioe) |
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128 | return self.E_NO_ERROR, str(filesize) |
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129 | if command == 'read': |
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130 | if self.filein is None: |
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131 | raise error.general('tftp-reader: read when not open') |
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132 | if 'blksize' not in kwargs: |
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133 | raise error.general('tftp-reader: invalid read: no blksize') |
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134 | # pylint: disable=bare-except |
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135 | try: |
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136 | return self.E_NO_ERROR, self.filein.read(kwargs['blksize']) |
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137 | except IOError as ioe: |
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138 | return self.E_NOT_DEFINED, str(ioe) |
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139 | except: |
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140 | return self.E_NOT_DEFINED, 'unknown error' |
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141 | if command == 'close': |
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142 | if self.filein is not None: |
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143 | self.filein.close() |
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144 | self.filein = None |
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145 | return self.E_NO_ERROR, "closed" |
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146 | return self.E_NOT_DEFINED, 'invalid reader state' |
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147 | |
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148 | @staticmethod |
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149 | def _pack_bytes(data=None): |
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150 | bdata = bytearray() |
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151 | if data is not None: |
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152 | if not isinstance(data, list): |
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153 | data = [data] |
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154 | for item in data: |
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155 | if isinstance(item, int): |
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156 | bdata.append(item >> 8) |
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157 | bdata.append(item & 0xff) |
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158 | elif isinstance(item, str): |
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159 | bdata.extend(item.encode()) |
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160 | bdata.append(0) |
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161 | else: |
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162 | bdata.extend(item) |
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163 | return bdata |
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164 | |
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165 | def _response(self, opcode, data): |
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166 | code = self.opcodes.index(opcode) |
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167 | if code == 0 or code >= len(self.opcodes): |
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168 | raise error.general('invalid opcode: ' + opcode) |
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169 | bdata = self._pack_bytes([code, data]) |
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170 | #print(''.join(format(x, '02x') for x in bdata)) |
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171 | return bdata |
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172 | |
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173 | def _error_response(self, code, message): |
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174 | if log.tracing: |
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175 | log.trace('tftp: error: %s:%d: %d: %s' % |
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176 | (self.host, self.port, code, message)) |
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177 | self.finished = True |
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178 | return self._response('ERROR', self._pack_bytes([code, message, 0])) |
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179 | |
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180 | def _data_response(self, block, data): |
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181 | if len(data) < self.block_size: |
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182 | self.finished = True |
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183 | return self._response('DATA', self._pack_bytes([block, data])) |
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184 | |
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185 | def _oack_response(self, data): |
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186 | self.resends += 1 |
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187 | if self.resends >= self.resends_limit: |
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188 | return self._error_response(self.E_NOT_DEFINED, |
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189 | 'resend limit reached') |
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190 | return self._response('OACK', self._pack_bytes(data)) |
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191 | |
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192 | def _next_block(self, block): |
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193 | # has the current block been acknowledged? |
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194 | if block == self.block: |
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195 | self.resends = 0 |
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196 | self.block += 1 |
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197 | err, data = self.data_reader('read', blksize=self.block_size) |
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198 | data = bytearray(data) |
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199 | if err != self.E_NO_ERROR: |
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200 | return self._error_response(err, data) |
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201 | # close if the length of data is less than the block size |
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202 | if len(data) < self.block_size: |
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203 | self.data_reader('close') |
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204 | self.last_data = data |
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205 | else: |
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206 | self.resends += 1 |
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207 | if self.resends >= self.resends_limit: |
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208 | return self._error_response(self.E_NOT_DEFINED, |
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209 | 'resend limit reached') |
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210 | data = self.last_data |
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211 | return self._data_response(self.block, data) |
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212 | |
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213 | def _read_req(self, data): |
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214 | # if the last block is not 0 something has gone wrong and |
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215 | # TID match. Restart the session. It could be the client |
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216 | # is a simple implementation that does not move the send |
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217 | # port on each retry. |
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218 | if self.block != 0: |
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219 | self.data_reader('close') |
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220 | self._reinit() |
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221 | # Get the filename, mode and options |
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222 | self.filename = self.get_option('filename', data) |
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223 | if self.filename is None: |
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224 | return self._error_response(self.E_NOT_DEFINED, |
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225 | 'filename not found in request') |
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226 | if self.forced_file is not None: |
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227 | self.filename = self.forced_file |
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228 | # open the reader |
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229 | err, message = self.data_reader('open', filename=self.filename) |
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230 | if err != self.E_NO_ERROR: |
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231 | return self._error_response(err, message) |
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232 | # the no error on open message is the file size |
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233 | try: |
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234 | tsize = int(message) |
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235 | except ValueError: |
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236 | tsize = 0 |
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237 | mode = self.get_option('mode', data) |
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238 | if mode is None: |
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239 | return self._error_response(self.E_NOT_DEFINED, |
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240 | 'mode not found in request') |
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241 | oack_data = self._pack_bytes() |
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242 | value = self.get_option('timeout', data) |
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243 | if value is not None: |
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244 | oack_data += self._pack_bytes(['timeout', value]) |
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245 | self.timeout = int(value) |
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246 | value = self.get_option('blksize', data) |
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247 | if value is not None: |
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248 | oack_data += self._pack_bytes(['blksize', value]) |
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249 | self.block_size = int(value) |
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250 | else: |
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251 | self.block_size = 512 |
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252 | value = self.get_option('tsize', data) |
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253 | if value is not None and tsize > 0: |
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254 | oack_data += self._pack_bytes(['tsize', str(tsize)]) |
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255 | # Send the options ack |
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256 | return self._oack_response(oack_data) |
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257 | |
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258 | def _write_req(self): |
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259 | # WRQ is not supported |
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260 | return self._error_response(self.E_ILLEGAL_TFTP_OP, |
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261 | "writes not supported") |
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262 | |
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263 | def _op_ack(self, data): |
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264 | # send the next block of data |
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265 | block = (data[2] << 8) | data[3] |
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266 | return self._next_block(block) |
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267 | |
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268 | def process(self, host, port, data): |
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269 | '''Process the incoming client data sending a response. If the session |
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270 | has finished return None. |
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271 | ''' |
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272 | if host != self.host and port != self.port: |
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273 | return self._error_response(self.E_UKNOWN_TID, |
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274 | 'unkown transfer ID') |
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275 | if self.finished: |
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276 | return None |
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277 | opcode = (data[0] << 8) | data[1] |
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278 | if opcode == self.OP_RRQ: |
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279 | return self._read_req(data) |
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280 | if opcode in [self.OP_WRQ, self.OP_DATA]: |
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281 | return self._write_req() |
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282 | if opcode == self.OP_ACK: |
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283 | return self._op_ack(data) |
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284 | return self._error_response(self.E_ILLEGAL_TFTP_OP, |
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285 | "unknown or unsupported opcode") |
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286 | |
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287 | def decode(self, host, port, data): |
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288 | '''Decode the packet for diagnostic purposes. |
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289 | ''' |
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290 | # pylint: disable=too-many-branches |
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291 | out = '' |
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292 | dlen = len(data) |
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293 | if dlen > 2: |
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294 | opcode = (data[0] << 8) | data[1] |
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295 | if 0 < opcode < len(self.opcodes): |
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296 | if opcode in [self.OP_RRQ, self.OP_WRQ]: |
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297 | out += ' ' + self.opcodes[opcode] + ', ' |
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298 | i = 2 |
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299 | while data[i] != 0: |
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300 | out += chr(data[i]) |
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301 | i += 1 |
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302 | while i < dlen - 1: |
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303 | out += ', ' |
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304 | i += 1 |
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305 | while data[i] != 0: |
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306 | out += chr(data[i]) |
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307 | i += 1 |
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308 | elif opcode == self.OP_DATA: |
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309 | block = (data[2] << 8) | data[3] |
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310 | out += ' ' + self.opcodes[opcode] + ', ' |
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311 | out += '#' + str(block) + ', ' |
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312 | if dlen > 4: |
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313 | out += '%02x%02x..%02x%02x' % (data[4], data[5], |
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314 | data[-2], data[-1]) |
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315 | else: |
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316 | out += '%02x%02x%02x%02x' % (data[4], data[5], data[6], |
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317 | data[6]) |
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318 | out += ',' + str(dlen - 4) |
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319 | elif opcode == self.OP_ACK: |
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320 | block = (data[2] << 8) | data[3] |
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321 | out += ' ' + self.opcodes[opcode] + ' ' + str(block) |
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322 | elif opcode == self.OP_ERROR: |
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323 | out += 'E ' + self.opcodes[opcode] + ', ' |
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324 | out += str((data[2] << 8) | (data[3])) |
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325 | out += ': ' + str(data[4:].decode()) |
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326 | i = 2 |
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327 | while data[i] != 0: |
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328 | out += chr(data[i]) |
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329 | i += 1 |
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330 | elif opcode == self.OP_OACK: |
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331 | out += ' ' + self.opcodes[opcode] |
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332 | i = 1 |
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333 | while i < dlen - 1: |
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334 | out += ', ' |
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335 | i += 1 |
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336 | while data[i] != 0: |
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337 | out += chr(data[i]) |
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338 | i += 1 |
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339 | else: |
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340 | out += 'E INV(%d)' % (opcode) |
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341 | else: |
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342 | out += 'E INVALID LENGTH' |
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343 | return out[:2] + '[%s:%d] (%d) ' % (host, port, len(data)) + out[2:] |
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344 | |
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345 | @staticmethod |
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346 | def get_option(option, data): |
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347 | '''Get the option from the TFTP packet.''' |
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348 | dlen = len(data) - 1 |
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349 | opcode = (data[0] << 8) | data[1] |
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350 | next_option = False |
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351 | if opcode in [1, 2]: |
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352 | count = 0 |
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353 | i = 2 |
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354 | while i < dlen: |
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355 | value = '' |
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356 | while data[i] != 0: |
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357 | value += chr(data[i]) |
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358 | i += 1 |
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359 | i += 1 |
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360 | if option == 'filename' and count == 0: |
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361 | return value |
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362 | if option == 'mode' and count == 1: |
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363 | return value |
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364 | if value == option and (count % 1) == 0: |
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365 | next_option = True |
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366 | elif next_option: |
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367 | return value |
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368 | count += 1 |
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369 | return None |
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370 | |
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371 | def get_timeout(self, default_timeout, timeout_guard): |
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372 | '''Get the timeout. The timeout can be an option.''' |
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373 | if self.timeout == 0: |
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374 | return self.timeout + timeout_guard |
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375 | return default_timeout |
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376 | |
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377 | def get_block_size(self): |
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378 | '''Get the block size. The block size can be an option.''' |
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379 | return self.block_size |
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380 | |
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381 | |
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382 | class udp_handler(socketserver.BaseRequestHandler): |
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383 | '''TFTP UDP handler for a TFTP session.''' |
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384 | def _notice(self, text): |
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385 | if self.server.tftp.notices: |
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386 | log.notice(text) |
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387 | else: |
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388 | log.trace(text) |
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389 | |
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390 | def handle_session(self, index): |
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391 | '''Handle the TFTP session data.''' |
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392 | # pylint: disable=too-many-locals |
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393 | # pylint: disable=broad-except |
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394 | # pylint: disable=too-many-branches |
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395 | # pylint: disable=too-many-statements |
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396 | client_ip = self.client_address[0] |
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397 | client_port = self.client_address[1] |
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398 | client = '%s:%i' % (client_ip, client_port) |
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399 | self._notice('] tftp: %d: start: %s' % (index, client)) |
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400 | try: |
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401 | session = tftp_session(client_ip, client_port, |
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402 | self.server.tftp.base, |
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403 | self.server.tftp.forced_file, |
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404 | self.server.tftp.reader) |
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405 | data = bytearray(self.request[0]) |
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406 | response = session.process(client_ip, client_port, data) |
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407 | if response is not None: |
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408 | if log.tracing and self.server.tftp.packet_trace: |
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409 | log.trace(' > ' + |
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410 | session.decode(client_ip, client_port, data)) |
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411 | timeout = session.get_timeout(self.server.tftp.timeout, 1) |
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412 | sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM) |
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413 | sock.bind(('', 0)) |
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414 | sock.settimeout(timeout) |
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415 | while response is not None: |
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416 | if log.tracing and self.server.tftp.packet_trace: |
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417 | log.trace( |
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418 | ' < ' + |
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419 | session.decode(client_ip, client_port, response)) |
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420 | sock.sendto(response, (client_ip, client_port)) |
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421 | if session.finished: |
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422 | break |
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423 | try: |
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424 | data, address = sock.recvfrom(2 + 2 + |
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425 | session.get_block_size()) |
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426 | data = bytearray(data) |
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427 | if log.tracing and self.server.tftp.packet_trace: |
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428 | log.trace( |
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429 | ' > ' + |
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430 | session.decode(address[0], address[1], data)) |
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431 | except socket.error as serr: |
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432 | if log.tracing: |
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433 | log.trace('] tftp: %d: receive: %s: error: %s' \ |
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434 | % (index, client, serr)) |
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435 | return |
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436 | except socket.gaierror as serr: |
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437 | if log.tracing: |
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438 | log.trace('] tftp: %d: receive: %s: error: %s' \ |
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439 | % (index, client, serr)) |
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440 | return |
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441 | response = session.process(address[0], address[1], data) |
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442 | except error.general as gerr: |
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443 | self._notice('] tftp: %dd: error: %s' % (index, gerr)) |
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444 | except error.internal as ierr: |
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445 | self._notice('] tftp: %d: error: %s' % (index, ierr)) |
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446 | except error.exit: |
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447 | pass |
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448 | except KeyboardInterrupt: |
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449 | pass |
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450 | except Exception as exp: |
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451 | if self.server.tftp.exception_is_raise: |
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452 | raise |
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453 | self._notice('] tftp: %d: error: %s: %s' % (index, type(exp), exp)) |
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454 | self._notice('] tftp: %d: end: %s' % (index, client)) |
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455 | |
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456 | def handle(self): |
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457 | '''The UDP server handle method.''' |
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458 | if self.server.tftp.sessions is None \ |
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459 | or self.server.tftp.session < self.server.tftp.sessions: |
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460 | self.handle_session(self.server.tftp.next_session()) |
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461 | |
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462 | |
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463 | class udp_server(socketserver.ThreadingMixIn, socketserver.UDPServer): |
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464 | '''UDP server. Default behaviour.''' |
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465 | |
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466 | |
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467 | class tftp_server(object): |
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468 | '''TFTP server runs a UDP server to handle TFTP sessions.''' |
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469 | |
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470 | # pylint: disable=useless-object-inheritance |
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471 | # pylint: disable=too-many-instance-attributes |
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472 | |
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473 | def __init__(self, |
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474 | host, |
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475 | port, |
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476 | timeout=10, |
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477 | base=None, |
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478 | forced_file=None, |
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479 | sessions=None, |
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480 | reader=None): |
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481 | # pylint: disable=too-many-arguments |
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482 | self.lock = threading.Lock() |
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483 | self.notices = False |
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484 | self.packet_trace = False |
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485 | self.exception_is_raise = False |
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486 | self.timeout = timeout |
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487 | self.host = host |
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488 | self.port = port |
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489 | self.server = None |
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490 | self.server_thread = None |
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491 | if base is None: |
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492 | base = os.getcwd() |
---|
493 | self.base = base |
---|
494 | self.forced_file = forced_file |
---|
495 | if sessions is not None and not isinstance(sessions, int): |
---|
496 | raise error.general('tftp session count is not a number') |
---|
497 | self.sessions = sessions |
---|
498 | self.session = 0 |
---|
499 | self.reader = reader |
---|
500 | |
---|
501 | def __del__(self): |
---|
502 | self.stop() |
---|
503 | |
---|
504 | def _lock(self): |
---|
505 | self.lock.acquire() |
---|
506 | |
---|
507 | def _unlock(self): |
---|
508 | self.lock.release() |
---|
509 | |
---|
510 | def start(self): |
---|
511 | '''Start the TFTP server. Returns once started.''' |
---|
512 | # pylint: disable=attribute-defined-outside-init |
---|
513 | if log.tracing: |
---|
514 | log.trace('] tftp: server: %s:%i' % (self.host, self.port)) |
---|
515 | if self.host == 'all': |
---|
516 | host = '' |
---|
517 | else: |
---|
518 | host = self.host |
---|
519 | try: |
---|
520 | self.server = udp_server((host, self.port), udp_handler) |
---|
521 | except Exception as exp: |
---|
522 | raise error.general('tftp server create: %s' % (exp)) |
---|
523 | # We cannot set tftp in __init__ because the object is created |
---|
524 | # in a separate package. |
---|
525 | self.server.tftp = self |
---|
526 | self.server_thread = threading.Thread(target=self.server.serve_forever) |
---|
527 | self.server_thread.daemon = True |
---|
528 | self.server_thread.start() |
---|
529 | |
---|
530 | def stop(self): |
---|
531 | '''Stop the TFTP server and close the server port.''' |
---|
532 | self._lock() |
---|
533 | try: |
---|
534 | if self.server is not None: |
---|
535 | self.server.shutdown() |
---|
536 | self.server.server_close() |
---|
537 | self.server = None |
---|
538 | finally: |
---|
539 | self._unlock() |
---|
540 | |
---|
541 | def run(self): |
---|
542 | '''Run the TFTP server for the specified number of sessions.''' |
---|
543 | running = True |
---|
544 | while running: |
---|
545 | period = 1 |
---|
546 | self._lock() |
---|
547 | if self.server is None: |
---|
548 | running = False |
---|
549 | period = 0 |
---|
550 | elif self.sessions is not None: |
---|
551 | if self.sessions == 0: |
---|
552 | running = False |
---|
553 | period = 0 |
---|
554 | else: |
---|
555 | period = 0.25 |
---|
556 | self._unlock() |
---|
557 | if period > 0: |
---|
558 | time.sleep(period) |
---|
559 | self.stop() |
---|
560 | |
---|
561 | def get_session(self): |
---|
562 | '''Return the session count.''' |
---|
563 | count = 0 |
---|
564 | self._lock() |
---|
565 | try: |
---|
566 | count = self.session |
---|
567 | finally: |
---|
568 | self._unlock() |
---|
569 | return count |
---|
570 | |
---|
571 | def next_session(self): |
---|
572 | '''Return the next session number.''' |
---|
573 | count = 0 |
---|
574 | self._lock() |
---|
575 | try: |
---|
576 | self.session += 1 |
---|
577 | count = self.session |
---|
578 | finally: |
---|
579 | self._unlock() |
---|
580 | return count |
---|
581 | |
---|
582 | def enable_notices(self): |
---|
583 | '''Call to enable notices. The server is quiet without this call.''' |
---|
584 | self._lock() |
---|
585 | self.notices = True |
---|
586 | self._unlock() |
---|
587 | |
---|
588 | def trace_packets(self): |
---|
589 | '''Call to enable packet tracing as a diagnostic.''' |
---|
590 | self._lock() |
---|
591 | self.packet_trace = True |
---|
592 | self._unlock() |
---|
593 | |
---|
594 | def except_is_raise(self): |
---|
595 | '''If True a standard exception will generate a backtrace.''' |
---|
596 | self.exception_is_raise = True |
---|
597 | |
---|
598 | |
---|
599 | def load_log(logfile): |
---|
600 | '''Set the log file.''' |
---|
601 | if logfile is None: |
---|
602 | log.default = log.log(streams=['stdout']) |
---|
603 | else: |
---|
604 | log.default = log.log(streams=[logfile]) |
---|
605 | |
---|
606 | |
---|
607 | def run(args=sys.argv, command_path=None): |
---|
608 | '''Run a TFTP server session.''' |
---|
609 | # pylint: disable=dangerous-default-value |
---|
610 | # pylint: disable=unused-argument |
---|
611 | # pylint: disable=too-many-branches |
---|
612 | # pylint: disable=too-many-statements |
---|
613 | ecode = 0 |
---|
614 | notice = None |
---|
615 | server = None |
---|
616 | # pylint: disable=bare-except |
---|
617 | try: |
---|
618 | description = 'A TFTP Server that supports a read only TFTP session.' |
---|
619 | |
---|
620 | nice_cwd = os.path.relpath(os.getcwd()) |
---|
621 | if len(nice_cwd) > len(os.path.abspath(nice_cwd)): |
---|
622 | nice_cwd = os.path.abspath(nice_cwd) |
---|
623 | |
---|
624 | argsp = argparse.ArgumentParser(prog='rtems-tftp-server', |
---|
625 | description=description) |
---|
626 | argsp.add_argument('-l', |
---|
627 | '--log', |
---|
628 | help='log file.', |
---|
629 | type=str, |
---|
630 | default=None) |
---|
631 | argsp.add_argument('-v', |
---|
632 | '--trace', |
---|
633 | help='enable trace logging for debugging.', |
---|
634 | action='store_true', |
---|
635 | default=False) |
---|
636 | argsp.add_argument('--trace-packets', |
---|
637 | help='enable trace logging of packets.', |
---|
638 | action='store_true', |
---|
639 | default=False) |
---|
640 | argsp.add_argument('--show-backtrace', |
---|
641 | help='show the exception backtrace.', |
---|
642 | action='store_true', |
---|
643 | default=False) |
---|
644 | argsp.add_argument( |
---|
645 | '-B', |
---|
646 | '--bind', |
---|
647 | help='address to bind the server too (default: %(default)s).', |
---|
648 | type=str, |
---|
649 | default='all') |
---|
650 | argsp.add_argument( |
---|
651 | '-P', |
---|
652 | '--port', |
---|
653 | help='port to bind the server too (default: %(default)s).', |
---|
654 | type=int, |
---|
655 | default='69') |
---|
656 | argsp.add_argument('-t', '--timeout', |
---|
657 | help = 'timeout in seconds, client can override ' \ |
---|
658 | '(default: %(default)s).', |
---|
659 | type = int, default = '10') |
---|
660 | argsp.add_argument( |
---|
661 | '-b', |
---|
662 | '--base', |
---|
663 | help='base path, not checked (default: %(default)s).', |
---|
664 | type=str, |
---|
665 | default=nice_cwd) |
---|
666 | argsp.add_argument( |
---|
667 | '-F', |
---|
668 | '--force-file', |
---|
669 | help='force the file to be downloaded overriding the client.', |
---|
670 | type=str, |
---|
671 | default=None) |
---|
672 | argsp.add_argument('-s', '--sessions', |
---|
673 | help = 'number of TFTP sessions to run before exiting ' \ |
---|
674 | '(default: forever.', |
---|
675 | type = int, default = None) |
---|
676 | |
---|
677 | argopts = argsp.parse_args(args[1:]) |
---|
678 | |
---|
679 | load_log(argopts.log) |
---|
680 | log.notice('RTEMS Tools - TFTP Server, %s' % (version.string())) |
---|
681 | log.output(log.info(args)) |
---|
682 | log.tracing = argopts.trace |
---|
683 | |
---|
684 | server = tftp_server(argopts.bind, argopts.port, argopts.timeout, |
---|
685 | argopts.base, argopts.force_file, |
---|
686 | argopts.sessions) |
---|
687 | server.enable_notices() |
---|
688 | if argopts.trace_packets: |
---|
689 | server.trace_packets() |
---|
690 | if argopts.show_backtrace: |
---|
691 | server.except_is_raise() |
---|
692 | |
---|
693 | try: |
---|
694 | server.start() |
---|
695 | server.run() |
---|
696 | finally: |
---|
697 | server.stop() |
---|
698 | |
---|
699 | except error.general as gerr: |
---|
700 | notice = str(gerr) |
---|
701 | ecode = 1 |
---|
702 | except error.internal as ierr: |
---|
703 | notice = str(ierr) |
---|
704 | ecode = 1 |
---|
705 | except error.exit: |
---|
706 | pass |
---|
707 | except KeyboardInterrupt: |
---|
708 | notice = 'abort: user terminated' |
---|
709 | ecode = 1 |
---|
710 | except SystemExit: |
---|
711 | pass |
---|
712 | except: |
---|
713 | notice = 'abort: unknown error' |
---|
714 | ecode = 1 |
---|
715 | if server is not None: |
---|
716 | del server |
---|
717 | if notice is not None: |
---|
718 | log.stderr(notice) |
---|
719 | sys.exit(ecode) |
---|
720 | |
---|
721 | |
---|
722 | if __name__ == "__main__": |
---|
723 | run() |
---|