stm32eeprom_parser.py
11014 bytes
1#!/usr/bin/env python
2#
3# Copyright 2021 Don Kjer
4#
5# This program is free software: you can redistribute it and/or modify
6# it under the terms of the GNU General Public License as published by
7# the Free Software Foundation, either version 2 of the License, or
8# (at your option) any later version.
9#
10# This program is distributed in the hope that it will be useful,
11# but WITHOUT ANY WARRANTY; without even the implied warranty of
12# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13# GNU General Public License for more details.
14#
15# You should have received a copy of the GNU General Public License
16# along with this program. If not, see <http://www.gnu.org/licenses/>.
17#
18
19from __future__ import print_function
20
21import argparse
22from struct import pack, unpack
23import os, sys
24
25MAGIC_FEEA = '\xea\xff\xfe\xff'
26
27MAGIC_FEE9 = '\x16\x01'
28EMPTY_WORD = '\xff\xff'
29WORD_ENCODING = 0x8000
30VALUE_NEXT = 0x6000
31VALUE_RESERVED = 0x4000
32VALUE_ENCODED = 0x2000
33BYTE_RANGE = 0x80
34
35CHUNK_SIZE = 1024
36
37STRUCT_FMTS = {
38 1: 'B',
39 2: 'H',
40 4: 'I'
41}
42PRINTABLE='0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ!"#$%&\'()*+,-./:;<=>?@[\\]^_`{|}~ '
43
44EECONFIG_V1 = [
45 ("MAGIC", 0, 2),
46 ("DEBUG", 2, 1),
47 ("DEFAULT_LAYER", 3, 1),
48 ("KEYMAP", 4, 1),
49 ("MOUSEKEY_ACCEL", 5, 1),
50 ("BACKLIGHT", 6, 1),
51 ("AUDIO", 7, 1),
52 ("RGBLIGHT", 8, 4),
53 ("UNICODEMODE", 12, 1),
54 ("STENOMODE", 13, 1),
55 ("HANDEDNESS", 14, 1),
56 ("KEYBOARD", 15, 4),
57 ("USER", 19, 4),
58 ("VELOCIKEY", 23, 1),
59 ("HAPTIC", 24, 4),
60 ("MATRIX", 28, 4),
61 ("MATRIX_EXTENDED", 32, 2),
62 ("KEYMAP_UPPER_BYTE", 34, 1),
63]
64VIABASE_V1 = 35
65
66VERBOSE = False
67
68def parseArgs():
69 parser = argparse.ArgumentParser(description='Decode an STM32 emulated eeprom dump')
70 parser.add_argument('-s', '--size', type=int,
71 help='Size of the emulated eeprom (default: input_size / 2)')
72 parser.add_argument('-o', '--output', help='File to write decoded eeprom to')
73 parser.add_argument('-y', '--layout-options-size', type=int,
74 help='VIA layout options size (default: 1)', default=1)
75 parser.add_argument('-t', '--custom-config-size', type=int,
76 help='VIA custom config size (default: 0)', default=0)
77 parser.add_argument('-l', '--layers', type=int,
78 help='VIA keyboard layers (default: 4)', default=4)
79 parser.add_argument('-r', '--rows', type=int, help='VIA matrix rows')
80 parser.add_argument('-c', '--cols', type=int, help='VIA matrix columns')
81 parser.add_argument('-m', '--macros', type=int,
82 help='VIA macro count (default: 16)', default=16)
83 parser.add_argument('-C', '--canonical', action='store_true',
84 help='Canonical hex+ASCII display.')
85 parser.add_argument('-v', '--verbose', action='store_true', help='Verbose output')
86 parser.add_argument('input', help='Raw contents of the STM32 flash area used to emulate eeprom')
87 return parser.parse_args()
88
89
90def decodeEepromFEEA(in_file, size):
91 decoded=size*[None]
92 pos = 0
93 while True:
94 chunk = in_file.read(CHUNK_SIZE)
95 for i in range(0, len(chunk), 2):
96 decoded[pos] = unpack('B', chunk[i])[0]
97 pos += 1
98 if pos >= size:
99 break
100
101 if len(chunk) < CHUNK_SIZE or pos >= size:
102 break
103 return decoded
104
105def decodeEepromFEE9(in_file, size):
106 decoded=size*[None]
107 pos = 0
108 # Read compacted flash
109 while True:
110 read_size = min(size - pos, CHUNK_SIZE)
111 chunk = in_file.read(read_size)
112 for i in range(len(chunk)):
113 decoded[pos] = unpack('B', chunk[i])[0] ^ 0xFF
114 pos += 1
115 if pos >= size:
116 break
117
118 if len(chunk) < read_size or pos >= size:
119 break
120 if VERBOSE:
121 print("COMPACTED EEPROM:")
122 dumpBinary(decoded, True)
123 print("WRITE LOG:")
124 # Read write log
125 while True:
126 entry = in_file.read(2)
127 if len(entry) < 2:
128 print("Partial log address at position 0x%04x" % pos, file=sys.stderr)
129 break
130 pos += 2
131
132 if entry == EMPTY_WORD:
133 break
134
135 be_entry = unpack('>H', entry)[0]
136 entry = unpack('H', entry)[0]
137 if not (entry & WORD_ENCODING):
138 address = entry >> 8
139 decoded[address] = entry & 0xFF
140 if VERBOSE:
141 print("[0x%04x]: BYTE 0x%02x = 0x%02x" % (be_entry, address, decoded[address]))
142 else:
143 if (entry & VALUE_NEXT) == VALUE_NEXT:
144 # Read next word as value
145 value = in_file.read(2)
146 if len(value) < 2:
147 print("Partial log value at position 0x%04x" % pos, file=sys.stderr)
148 break
149 pos += 2
150 address = entry & 0x1FFF
151 address <<= 1
152 address += BYTE_RANGE
153 decoded[address] = unpack('B', value[0])[0] ^ 0xFF
154 decoded[address+1] = unpack('B', value[1])[0] ^ 0xFF
155 be_value = unpack('>H', value)[0]
156 if VERBOSE:
157 print("[0x%04x 0x%04x]: WORD 0x%04x = 0x%02x%02x" % (be_entry, be_value, address, decoded[address+1], decoded[address]))
158 else:
159 # Reserved for future use
160 if entry & VALUE_RESERVED:
161 if VERBOSE:
162 print("[0x%04x]: RESERVED 0x%04x" % (be_entry, address))
163 continue
164 address = entry & 0x1FFF
165 address <<= 1
166 decoded[address] = (entry & VALUE_ENCODED) >> 13
167 decoded[address+1] = 0
168 if VERBOSE:
169 print("[0x%04x]: ENCODED 0x%04x = 0x%02x%02x" % (be_entry, address, decoded[address+1], decoded[address]))
170
171 return decoded
172
173def dumpBinary(data, canonical):
174 def display(pos, row):
175 print("%04x" % pos, end='')
176 for i in range(len(row)):
177 if i % 8 == 0:
178 print(" ", end='')
179 char = row[i]
180 if char is None:
181 print(" ", end='')
182 else:
183 print(" %02x" % row[i], end='')
184 if canonical:
185 print(" |", end='')
186 for i in range(len(row)):
187 char = row[i]
188 if char is None:
189 char = " "
190 else:
191 char = chr(char)
192 if char not in PRINTABLE:
193 char = "."
194 print(char, end='')
195 print("|", end='')
196
197 print("")
198
199 size = len(data)
200 prev_row = ''
201 first_repeat = True
202 for pos in range(0, size, 16):
203 row=data[pos:pos+16]
204 row[len(row):16] = (16-len(row))*[None]
205 if row == prev_row:
206 if first_repeat:
207 print("*")
208 first_repeat = False
209 else:
210 first_repeat = True
211 display(pos, row)
212 prev_row = row
213 print("%04x" % (pos+16))
214
215def dumpEeconfig(data, eeconfig):
216 print("EECONFIG:")
217 for (name, pos, length) in eeconfig:
218 fmt = STRUCT_FMTS[length]
219 value = unpack(fmt, ''.join([chr(x) for x in data[pos:pos+length]]))[0]
220 print(("%%04x %%s = 0x%%0%dx" % (length * 2)) % (pos, name, value))
221
222def dumpVia(data, base, layers, cols, rows, macros,
223 layout_options_size, custom_config_size):
224 magicYear = data[base + 0]
225 magicMonth = data[base + 1]
226 magicDay = data[base + 2]
227 # Sanity check
228 if not 10 <= magicYear <= 0x99 or \
229 not 0 <= magicMonth <= 0x12 or \
230 not 0 <= magicDay <= 0x31:
231 print("ERROR: VIA Signature is not valid; Year:%x, Month:%x, Day:%x" % (magicYear, magicMonth, magicDay))
232 return
233 if cols is None or rows is None:
234 print("ERROR: VIA dump requires specifying --rows and --cols", file=sys.stderr)
235 return 2
236 print("VIA:")
237 # Decode magic
238 print("%04x MAGIC = 20%02x-%02x-%02x" % (base, magicYear, magicMonth, magicDay))
239 # Decode layout options
240 options = 0
241 pos = base + 3
242 for i in range(base+3, base+3+layout_options_size):
243 options = options << 8
244 options |= data[i]
245 print(("%%04x LAYOUT_OPTIONS = 0x%%0%dx" % (layout_options_size * 2)) % (pos, options))
246 pos += layout_options_size + custom_config_size
247 # Decode keycodes
248 keymap_size = layers * rows * cols * 2
249 if (pos + keymap_size) >= (len(data) - 1):
250 print("ERROR: VIA keymap requires %d bytes, but only %d available" % (keymap_size, len(data) - pos))
251 return 3
252 for layer in range(layers):
253 print("%s LAYER %d %s" % ('-'*int(cols*2.5), layer, '-'*int(cols*2.5)))
254 for row in range(rows):
255 print("%04x | " % pos, end='')
256 for col in range(cols):
257 keycode = (data[pos] << 8) | (data[pos+1])
258 print(" %04x" % keycode, end='')
259 pos += 2
260 print("")
261 # Decode macros
262 for macro_num in range(macros):
263 macro = ""
264 macro_pos = pos
265 while pos < len(data):
266 char = chr(data[pos])
267 pos += 1
268 if char == '\x00':
269 print("%04x MACRO[%d] = '%s'" % (macro_pos, macro_num, macro))
270 break
271 else:
272 macro += char
273 return 0
274
275
276def decodeSTM32Eeprom(input, canonical, size=None, output=None, **kwargs):
277 input_size = os.path.getsize(input)
278 if size is None:
279 size = input_size >> 1
280
281 # Read the first few bytes to check magic signature
282 with open(input, 'rb') as in_file:
283 magic=in_file.read(4)
284 in_file.seek(0)
285
286 if magic == MAGIC_FEEA:
287 decoded = decodeEepromFEEA(in_file, size)
288 eeconfig = EECONFIG_V1
289 via_base = VIABASE_V1
290 elif magic[:2] == MAGIC_FEE9:
291 decoded = decodeEepromFEE9(in_file, size)
292 eeconfig = EECONFIG_V1
293 via_base = VIABASE_V1
294 else:
295 print("Unknown magic signature: %s" % " ".join(["0x%02x" % ord(x) for x in magic]), file=sys.stderr)
296 return 1
297
298 if output is not None:
299 with open(output, 'wb') as out_file:
300 out_file.write(pack('%dB' % len(decoded), *decoded))
301 print("DECODED EEPROM:")
302 dumpBinary(decoded, canonical)
303 dumpEeconfig(decoded, eeconfig)
304 if kwargs['rows'] is not None and kwargs['cols'] is not None:
305 return dumpVia(decoded, via_base, **kwargs)
306
307 return 0
308
309def main():
310 global VERBOSE
311 kwargs = vars(parseArgs())
312 VERBOSE = kwargs.pop('verbose')
313 return decodeSTM32Eeprom(**kwargs)
314
315if __name__ == '__main__':
316 sys.exit(main())