Tetstack
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Tetstack
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I want to devour something, but kinda lazy to even get up.
SO IDK surprise stream, I will strea( I will just reverse engineer like a crackmes.one challenge)

@Tetstack
Live stream started
Never felt this dumb fr
OKay so the output we need "OMG you did it ..." has a reference XREF unconditional jump which jump into the second function ...
Yeah I will need paper for this one sec ...
so okay, if my input string length is 0 it will return 0
okay one sec I am not great with letters in maths
i gotta write it
Tetstack
okay one sec I am not great with letters in maths
OKay so what it does is take the character XOR it with the corresponding byte in the table at DAT_00... add that to a running total then return until tevery character is processed.
but there is one more function before it
this one
so the date have READ context
okay so what the function, which I suppose ... is

checksum = sum over i of (input[i] XOR table[i])
not sure
my maths might not be correct tho
Tetstack
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param_1[0] = pointer to the string's character buffer

param_1[1]=lenght of the string
00104028  81                                db                      81h
00104029 00 ?? 00h
0010402a 00 ?? 00h
0010402b 00 ?? 00h
0010402c ab ?? ABh
0010402d 00 ?? 00h
0010402e 00 ?? 00h
0010402f 00 ?? 00h
00104030 fe ?? FEh
00104031 00 ?? 00h
00104032 00 ?? 00h
00104033 00 ?? 00h
00104034 7b ?? 7Bh {
00104035 00 ?? 00h
00104036 00 ?? 00h

so this are the first 15 byte now gotta find a way