#!/usr/bin/env python # # Copyright 2021 Don Kjer # # This program is free software: you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation, either version 2 of the License, or # (at your option) any later version. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License # along with this program. If not, see <http://www.gnu.org/licenses/>. # from __future__ import print_function import argparse from struct import pack, unpack import os, sys MAGIC_FEEA = '\xea\xff\xfe\xff' MAGIC_FEE9 = '\x16\x01' EMPTY_WORD = '\xff\xff' WORD_ENCODING = 0x8000 VALUE_NEXT = 0x6000 VALUE_RESERVED = 0x4000 VALUE_ENCODED = 0x2000 BYTE_RANGE = 0x80 CHUNK_SIZE = 1024 STRUCT_FMTS = { 1: 'B', 2: 'H', 4: 'I' } PRINTABLE='0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ!"#$%&\'()*+,-./:;<=>?@[\\]^_`{|}~ ' EECONFIG_V1 = [ ("MAGIC", 0, 2), ("DEBUG", 2, 1), ("DEFAULT_LAYER", 3, 1), ("KEYMAP", 4, 1), ("MOUSEKEY_ACCEL", 5, 1), ("BACKLIGHT", 6, 1), ("AUDIO", 7, 1), ("RGBLIGHT", 8, 4), ("UNICODEMODE", 12, 1), ("STENOMODE", 13, 1), ("HANDEDNESS", 14, 1), ("KEYBOARD", 15, 4), ("USER", 19, 4), ("VELOCIKEY", 23, 1), ("HAPTIC", 24, 4), ("MATRIX", 28, 4), ("MATRIX_EXTENDED", 32, 2), ("KEYMAP_UPPER_BYTE", 34, 1), ] VIABASE_V1 = 35 VERBOSE = False def parseArgs(): parser = argparse.ArgumentParser(description='Decode an STM32 emulated eeprom dump') parser.add_argument('-s', '--size', type=int, help='Size of the emulated eeprom (default: input_size / 2)') parser.add_argument('-o', '--output', help='File to write decoded eeprom to') parser.add_argument('-y', '--layout-options-size', type=int, help='VIA layout options size (default: 1)', default=1) parser.add_argument('-t', '--custom-config-size', type=int, help='VIA custom config size (default: 0)', default=0) parser.add_argument('-l', '--layers', type=int, help='VIA keyboard layers (default: 4)', default=4) parser.add_argument('-r', '--rows', type=int, help='VIA matrix rows') parser.add_argument('-c', '--cols', type=int, help='VIA matrix columns') parser.add_argument('-m', '--macros', type=int, help='VIA macro count (default: 16)', default=16) parser.add_argument('-C', '--canonical', action='store_true', help='Canonical hex+ASCII display.') parser.add_argument('-v', '--verbose', action='store_true', help='Verbose output') parser.add_argument('input', help='Raw contents of the STM32 flash area used to emulate eeprom') return parser.parse_args() def decodeEepromFEEA(in_file, size): decoded=size*[None] pos = 0 while True: chunk = in_file.read(CHUNK_SIZE) for i in range(0, len(chunk), 2): decoded[pos] = unpack('B', chunk[i])[0] pos += 1 if pos >= size: break if len(chunk) < CHUNK_SIZE or pos >= size: break return decoded def decodeEepromFEE9(in_file, size): decoded=size*[None] pos = 0 # Read compacted flash while True: read_size = min(size - pos, CHUNK_SIZE) chunk = in_file.read(read_size) for i in range(len(chunk)): decoded[pos] = unpack('B', chunk[i])[0] ^ 0xFF pos += 1 if pos >= size: break if len(chunk) < read_size or pos >= size: break if VERBOSE: print("COMPACTED EEPROM:") dumpBinary(decoded, True) print("WRITE LOG:") # Read write log while True: entry = in_file.read(2) if len(entry) < 2: print("Partial log address at position 0x%04x" % pos, file=sys.stderr) break pos += 2 if entry == EMPTY_WORD: break be_entry = unpack('>H', entry)[0] entry = unpack('H', entry)[0] if not (entry & WORD_ENCODING): address = entry >> 8 decoded[address] = entry & 0xFF if VERBOSE: print("[0x%04x]: BYTE 0x%02x = 0x%02x" % (be_entry, address, decoded[address])) else: if (entry & VALUE_NEXT) == VALUE_NEXT: # Read next word as value value = in_file.read(2) if len(value) < 2: print("Partial log value at position 0x%04x" % pos, file=sys.stderr) break pos += 2 address = entry & 0x1FFF address <<= 1 address += BYTE_RANGE decoded[address] = unpack('B', value[0])[0] ^ 0xFF decoded[address+1] = unpack('B', value[1])[0] ^ 0xFF be_value = unpack('>H', value)[0] if VERBOSE: print("[0x%04x 0x%04x]: WORD 0x%04x = 0x%02x%02x" % (be_entry, be_value, address, decoded[address+1], decoded[address])) else: # Reserved for future use if entry & VALUE_RESERVED: if VERBOSE: print("[0x%04x]: RESERVED 0x%04x" % (be_entry, address)) continue address = entry & 0x1FFF address <<= 1 decoded[address] = (entry & VALUE_ENCODED) >> 13 decoded[address+1] = 0 if VERBOSE: print("[0x%04x]: ENCODED 0x%04x = 0x%02x%02x" % (be_entry, address, decoded[address+1], decoded[address])) return decoded def dumpBinary(data, canonical): def display(pos, row): print("%04x" % pos, end='') for i in range(len(row)): if i % 8 == 0: print(" ", end='') char = row[i] if char is None: print(" ", end='') else: print(" %02x" % row[i], end='') if canonical: print(" |", end='') for i in range(len(row)): char = row[i] if char is None: char = " " else: char = chr(char) if char not in PRINTABLE: char = "." print(char, end='') print("|", end='') print("") size = len(data) prev_row = '' first_repeat = True for pos in range(0, size, 16): row=data[pos:pos+16] row[len(row):16] = (16-len(row))*[None] if row == prev_row: if first_repeat: print("*") first_repeat = False else: first_repeat = True display(pos, row) prev_row = row print("%04x" % (pos+16)) def dumpEeconfig(data, eeconfig): print("EECONFIG:") for (name, pos, length) in eeconfig: fmt = STRUCT_FMTS[length] value = unpack(fmt, ''.join([chr(x) for x in data[pos:pos+length]]))[0] print(("%%04x %%s = 0x%%0%dx" % (length * 2)) % (pos, name, value)) def dumpVia(data, base, layers, cols, rows, macros, layout_options_size, custom_config_size): magicYear = data[base + 0] magicMonth = data[base + 1] magicDay = data[base + 2] # Sanity check if not 10 <= magicYear <= 0x99 or \ not 0 <= magicMonth <= 0x12 or \ not 0 <= magicDay <= 0x31: print("ERROR: VIA Signature is not valid; Year:%x, Month:%x, Day:%x" % (magicYear, magicMonth, magicDay)) return if cols is None or rows is None: print("ERROR: VIA dump requires specifying --rows and --cols", file=sys.stderr) return 2 print("VIA:") # Decode magic print("%04x MAGIC = 20%02x-%02x-%02x" % (base, magicYear, magicMonth, magicDay)) # Decode layout options options = 0 pos = base + 3 for i in range(base+3, base+3+layout_options_size): options = options << 8 options |= data[i] print(("%%04x LAYOUT_OPTIONS = 0x%%0%dx" % (layout_options_size * 2)) % (pos, options)) pos += layout_options_size + custom_config_size # Decode keycodes keymap_size = layers * rows * cols * 2 if (pos + keymap_size) >= (len(data) - 1): print("ERROR: VIA keymap requires %d bytes, but only %d available" % (keymap_size, len(data) - pos)) return 3 for layer in range(layers): print("%s LAYER %d %s" % ('-'*int(cols*2.5), layer, '-'*int(cols*2.5))) for row in range(rows): print("%04x | " % pos, end='') for col in range(cols): keycode = (data[pos] << 8) | (data[pos+1]) print(" %04x" % keycode, end='') pos += 2 print("") # Decode macros for macro_num in range(macros): macro = "" macro_pos = pos while pos < len(data): char = chr(data[pos]) pos += 1 if char == '\x00': print("%04x MACRO[%d] = '%s'" % (macro_pos, macro_num, macro)) break else: macro += char return 0 def decodeSTM32Eeprom(input, canonical, size=None, output=None, **kwargs): input_size = os.path.getsize(input) if size is None: size = input_size >> 1 # Read the first few bytes to check magic signature with open(input, 'rb') as in_file: magic=in_file.read(4) in_file.seek(0) if magic == MAGIC_FEEA: decoded = decodeEepromFEEA(in_file, size) eeconfig = EECONFIG_V1 via_base = VIABASE_V1 elif magic[:2] == MAGIC_FEE9: decoded = decodeEepromFEE9(in_file, size) eeconfig = EECONFIG_V1 via_base = VIABASE_V1 else: print("Unknown magic signature: %s" % " ".join(["0x%02x" % ord(x) for x in magic]), file=sys.stderr) return 1 if output is not None: with open(output, 'wb') as out_file: out_file.write(pack('%dB' % len(decoded), *decoded)) print("DECODED EEPROM:") dumpBinary(decoded, canonical) dumpEeconfig(decoded, eeconfig) if kwargs['rows'] is not None and kwargs['cols'] is not None: return dumpVia(decoded, via_base, **kwargs) return 0 def main(): global VERBOSE kwargs = vars(parseArgs()) VERBOSE = kwargs.pop('verbose') return decodeSTM32Eeprom(**kwargs) if __name__ == '__main__': sys.exit(main())