b01lers 3/2020

In this CTF, I had only solved first chall of rev.

Chugga chugga

• This chall is too long for lazy guy like me to do. I have admitted that I just only solve this chall 8 hours till the CTF end.

• As usual,  I open it on IDA and look for string, can't find anything there. Next, look at the fucntion name, I had main_main, main_win. 
• Look at main_win and follow the string, I see the congratulation!

• So that, come back to main_main and find the condition.
• Follow back from main_win, I can make a breakpoint to notice the trace of true condition.

• At the begin, after receive an input from fmt_Fscam, the input is stored at [rsp+0A8h+INPUT]
• rdx take the input, rcx stored the length of input (rdx and rcx could be changed).
• Our mission is rebuild a condition by following, change the input and solve the Simul Equation.

• This is note