2 ## This file is part of the libsigrokdecode project.
4 ## Copyright (C) 2018 Michalis Pappas <mpappas@fastmail.fm>
6 ## This program is free software; you can redistribute it and/or modify
7 ## it under the terms of the GNU General Public License as published by
8 ## the Free Software Foundation; either version 2 of the License, or
9 ## (at your option) any later version.
11 ## This program is distributed in the hope that it will be useful,
12 ## but WITHOUT ANY WARRANTY; without even the implied warranty of
13 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 ## GNU General Public License for more details.
16 ## You should have received a copy of the GNU General Public License
17 ## along with this program; if not, see <http://www.gnu.org/licenses/>.
20 import sigrokdecode as srd
22 WORD_ADDR_RESET = 0x00
23 WORD_ADDR_SLEEP = 0x01
25 WORD_ADDR_COMMAND = 0x03
27 WORD_ADDR = {0x00: 'RESET', 0x01: 'SLEEP', 0x02: 'IDLE', 0x03: 'COMMAND'}
29 OPCODE_DERIVE_KEY = 0x1c
33 OPCODE_CHECK_MAC = 0x28
41 OPCODE_UPDATE_EXTRA = 0x20
65 ZONES = {0x00: 'CONFIG', 0x01: 'OTP', 0x02: 'DATA'}
68 STATUS_CHECKMAC_FAIL = 0x01
69 STATUS_PARSE_ERROR = 0x03
70 STATUS_EXECUTION_ERROR = 0x0f
72 STATUS_CRC_COMM_ERROR = 0xff
75 0x00: 'Command success',
76 0x01: 'Checkmac failure',
78 0x0f: 'Execution error',
80 0xff: 'CRC / communications error',
83 class Decoder(srd.Decoder):
87 longname = 'Microchip ATSHA204A'
88 desc = 'Microchip ATSHA204A CryptoAuthentication device.'
91 outputs = ['atsha204a']
94 ('waddr', 'Word address'),
101 ('status', 'Status'),
102 ('warning', 'Warning'),
105 ('frame', 'Frame', (0, 1, 2, 3, 4, 5, 6)),
106 ('status', 'Status', (7,)),
107 ('warnings', 'Warnings', (8,)),
115 self.waddr = self.opcode = -1
116 self.ss_block = self.es_block = 0
120 self.out_ann = self.register(srd.OUTPUT_ANN)
122 def output_tx_bytes(self):
124 if len(b) < 1: # Ignore wakeup.
128 if self.waddr == WORD_ADDR_COMMAND:
131 if len(b) - 1 != count:
132 self.put_warning(b[0][0], b[-1][1],
133 'Invalid frame length: Got {}, expecting {} '.format(
136 self.opcode = b[2][2]
137 self.put_opcode(b[2])
138 self.put_param1(b[3])
139 self.put_param2([b[4], b[5]])
140 self.put_data(b[6:-2])
141 self.put_crc([b[-2], b[-1]])
143 def output_rx_bytes(self):
147 if self.waddr == WORD_ADDR_RESET:
148 self.put_data([b[1]])
149 self.put_crc([b[2], b[3]])
150 self.put_status(b[0][0], b[-1][1], b[1][2])
151 elif self.waddr == WORD_ADDR_COMMAND:
152 if count == 4: # Status / Error.
153 self.put_data([b[1]])
154 self.put_crc([b[2], b[3]])
155 self.put_status(b[0][0], b[-1][1], b[1][2])
157 self.put_data(b[1:-2])
158 self.put_crc([b[-2], b[-1]])
160 def putx(self, s, data):
161 self.put(s[0], s[1], self.out_ann, data)
163 def puty(self, s, data):
164 self.put(s[0][0], s[1][1], self.out_ann, data)
166 def putz(self, ss, es, data):
167 self.put(ss, es, self.out_ann, data)
169 def put_waddr(self, s):
170 self.putx(s, [0, ['Word addr: %s' % WORD_ADDR[s[2]]]])
172 def put_count(self, s):
173 self.putx(s, [1, ['Count: %s' % s[2]]])
175 def put_opcode(self, s):
176 self.putx(s, [2, ['Opcode: %s' % OPCODES[s[2]]]])
178 def put_param1(self, s):
180 if op in (OPCODE_CHECK_MAC, OPCODE_DEV_REV, OPCODE_HMAC, \
181 OPCODE_MAC, OPCODE_NONCE, OPCODE_RANDOM, OPCODE_SHA):
182 self.putx(s, [3, ['Mode: %02X' % s[2]]])
183 elif op == OPCODE_DERIVE_KEY:
184 self.putx(s, [3, ['Random: %s' % s[2]]])
185 elif op == OPCODE_GEN_DIG:
186 self.putx(s, [3, ['Zone: %s' % ZONES[s[2]]]])
187 elif op == OPCODE_LOCK:
188 self.putx(s, [3, ['Zone: {}, Summary: {}'.format(
189 'DATA/OTP' if s[2] else 'CONFIG',
190 'Ignored' if s[2] & 0x80 else 'Used')]])
191 elif op == OPCODE_PAUSE:
192 self.putx(s, [3, ['Selector: %02X' % s[2]]])
193 elif op == OPCODE_READ:
194 self.putx(s, [3, ['Zone: {}, Length: {}'.format(ZONES[s[2] & 0x03],
195 '32 bytes' if s[2] & 0x90 else '4 bytes')]])
196 elif op == OPCODE_WRITE:
197 self.putx(s, [3, ['Zone: {}, Encrypted: {}, Length: {}'.format(ZONES[s[2] & 0x03],
198 'Yes' if s[2] & 0x40 else 'No', '32 bytes' if s[2] & 0x90 else '4 bytes')]])
200 self.putx(s, [3, ['Param1: %02X' % s[2]]])
202 def put_param2(self, s):
204 if op == OPCODE_DERIVE_KEY:
205 self.puty(s, [4, ['TargetKey: {:02x} {:02x}'.format(s[1][2], s[0][2])]])
206 elif op in (OPCODE_NONCE, OPCODE_PAUSE, OPCODE_RANDOM):
207 self.puty(s, [4, ['Zero: {:02x} {:02x}'.format(s[1][2], s[0][2])]])
208 elif op in (OPCODE_HMAC, OPCODE_MAC, OPCODE_CHECK_MAC, OPCODE_GEN_DIG):
209 self.puty(s, [4, ['SlotID: {:02x} {:02x}'.format(s[1][2], s[0][2])]])
210 elif op == OPCODE_LOCK:
211 self.puty(s, [4, ['Summary: {:02x} {:02x}'.format(s[1][2], s[0][2])]])
212 elif op in (OPCODE_READ, OPCODE_WRITE):
213 self.puty(s, [4, ['Address: {:02x} {:02x}'.format(s[1][2], s[0][2])]])
214 elif op == OPCODE_UPDATE_EXTRA:
215 self.puty(s, [4, ['NewValue: {:02x}'.format(s[0][2])]])
217 self.puty(s, [4, ['-']])
219 def put_data(self, s):
223 if op == OPCODE_CHECK_MAC:
224 self.putz(s[0][0], s[31][1], [5, ['ClientChal: %s' % ' '.join(format(i[2], '02x') for i in s[0:31])]])
225 self.putz(s[32][0], s[63][1], [5, ['ClientResp: %s' % ' '.join(format(i[2], '02x') for i in s[32:63])]])
226 self.putz(s[64][0], s[76][1], [5, ['OtherData: %s' % ' '.join(format(i[2], '02x') for i in s[64:76])]])
227 elif op == OPCODE_DERIVE_KEY:
228 self.putz(s[0][0], s[31][1], [5, ['MAC: %s' % ' '.join(format(i[2], '02x') for i in s)]])
229 elif op == OPCODE_GEN_DIG:
230 self.putz(s[0][0], s[3][1], [5, ['OtherData: %s' % ' '.join(format(i[2], '02x') for i in s)]])
231 elif op == OPCODE_MAC:
232 self.putz(s[0][0], s[31][1], [5, ['Challenge: %s' % ' '.join(format(i[2], '02x') for i in s)]])
233 elif op == OPCODE_WRITE:
234 if len(s) > 32: # Value + MAC.
235 self.putz(s[0][0], s[-31][1], [5, ['Value: %s' % ' '.join(format(i[2], '02x') for i in s)]])
236 self.putz(s[-32][0], s[-1][1], [5, ['MAC: %s' % ' '.join(format(i[2], '02x') for i in s)]])
238 self.putz(s[0][0], s[-1][1], [5, ['Value: %s' % ' '.join(format(i[2], '02x') for i in s)]])
240 self.putz(s[0][0], s[-1][1], [5, ['Data: %s' % ' '.join(format(i[2], '02x') for i in s)]])
242 def put_crc(self, s):
243 self.puty(s, [6, ['CRC: {:02X} {:02X}'.format(s[0][2], s[1][2])]])
245 def put_status(self, ss, es, status):
246 self.putz(ss, es, [7, ['Status: %s' % STATUS[status]]])
248 def put_warning(self, ss, es, msg):
249 self.putz(ss, es, [8, ['Warning: %s' % msg]])
251 def decode(self, ss, es, data):
255 if self.state == 'IDLE':
256 # Wait for an I²C START condition.
259 self.state = 'GET SLAVE ADDR'
261 elif self.state == 'GET SLAVE ADDR':
262 # Wait for an address read/write operation.
263 if cmd == 'ADDRESS READ':
264 self.state = 'READ REGS'
265 elif cmd == 'ADDRESS WRITE':
266 self.state = 'WRITE REGS'
267 elif self.state == 'READ REGS':
268 if cmd == 'DATA READ':
269 self.bytes.append([ss, es, databyte])
272 # Reset the opcode before received data, as this causes
273 # responses to be displayed incorrectly.
275 self.output_rx_bytes()
279 elif self.state == 'WRITE REGS':
280 if cmd == 'DATA WRITE':
281 self.bytes.append([ss, es, databyte])
284 self.output_tx_bytes()