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December 9, 2017 09:09
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| #!/usr/bin/python3 | |
| import sys | |
| import hashlib | |
| BLOCKSIZE=0x200 | |
| f1d = {} | |
| f2h = [] | |
| with open(sys.argv[1], 'rb') as f: | |
| f1 = bytearray(f.read()) | |
| for i in range(0, len(f1), BLOCKSIZE): | |
| s = f1d.setdefault(hashlib.sha1(f1[i:i+BLOCKSIZE]).hexdigest(), []) | |
| s.append(i) | |
| del f1 | |
| with open(sys.argv[2], 'rb') as f: | |
| f2 = bytearray(f.read()) | |
| for i in range(0, len(f2), BLOCKSIZE): | |
| f2h.append(hashlib.sha1(f2[i:i+BLOCKSIZE]).hexdigest()) | |
| del f2 | |
| def getoffs(c): | |
| h = f2h[c] | |
| if h == "5c3eb80066420002bc3dcc7ca4ab6efad7ed4ae5": | |
| return "zeroes" | |
| if h == "9d0ac37bb3ec8c95990fd37a962a17a95ce97aa0": | |
| return "0xFF" | |
| if h == "3da96bc604d8819346a5ca15bb73d38f891cd08a": | |
| return "NOR 0x10000 repeating" | |
| offs = f1d.get(h, None) | |
| if offs is None: | |
| return "not in NOR" | |
| return offs | |
| def dospecialrun(code, c): | |
| run = 1 | |
| while True: | |
| offs = getoffs(c+run) | |
| if offs == code: | |
| run += 1 | |
| else: | |
| break | |
| return run | |
| def runstreak(c): | |
| offs = getoffs(c) | |
| if offs == 0xDEAD0000: | |
| return 1 | |
| run = 1 | |
| if type(offs) != list: | |
| run = dospecialrun(offs, c) | |
| if run > 1: | |
| print("ROM [0x{:X}, 0x{:X}) => {}".format(c*BLOCKSIZE, (c + run)*BLOCKSIZE, offs)) | |
| else: | |
| print("ROM 0x{:X} => {}".format(c*BLOCKSIZE, offs)) | |
| return run | |
| l = len(offs) | |
| if l > 1: | |
| print("ROM 0x{:X} => NOR {}".format(c*BLOCKSIZE, ", ".join(map(lambda x: "0x{:X}".format(x), offs)))); | |
| return 1 | |
| if l == 1: | |
| startnor, lastnor = offs[0], offs[0] | |
| while True: | |
| oln = lastnor | |
| if c+run >= len(f2h): | |
| break | |
| offs = f1d.get(f2h[c+run], None) | |
| if offs is None: | |
| break | |
| l = len(offs) | |
| if l == 0: | |
| break | |
| if l > 1: | |
| if lastnor+BLOCKSIZE in offs: | |
| lastnor += BLOCKSIZE | |
| run += 1 | |
| continue | |
| else: | |
| break | |
| if l == 1: | |
| lastnor = offs[0] | |
| if lastnor - oln == BLOCKSIZE: | |
| run += 1 | |
| continue | |
| else: | |
| break | |
| if run == 1: | |
| print("ROM 0x{:X} => NOR 0x{:X}".format(c*BLOCKSIZE, startnor)); | |
| else: | |
| print("ROM [0x{:X}, 0x{:X}) => NOR [0x{:X}, 0x{:X})".format(c*BLOCKSIZE, (c + run)*BLOCKSIZE, startnor, oln+BLOCKSIZE)) | |
| return run | |
| l = len(f2h) | |
| c = 0 | |
| while c < l: | |
| c += runstreak(c) |
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