Basic c++ code improvements

[Frago9876543210]

• function pointers replaced with decltype(&funcname)
• cmake min version is 3.0 now
• fixed clang-tidy warns
• knock_test upgraded to python 3
• appveyor uses visual studio 2019

[Frago9876543210]

do we need IAT at all with decltype and casts?

[Frago9876543210]

it works!

cl /c /GS- /FA knock.cpp
masm_shc.exe knock.asm knock_cleaned_file.asm
ml64 knock_cleaned_file.asm /link /entry:main /section:.text,ERW

.\knock_cleaned_file.exe

py .\knock_test.py --port 1337 --buf="9"
[+] Connecting to port: 1337
[+] Response: b'Y\x00\x00\x00'

py .\knock_test.py --port 1338 --buf="3"
[+] Connecting to port: 1338
[+] Response: b'E\x00\x00\x00'

py .\knock_test.py --port 1339 --buf="5"
[+] Connecting to port: 1339
[+] Response: b'S\x00\x00\x00'

[Frago9876543210]

would be nice to update paper

[hasherezade]

Thank you for your work! Upgrading to Python 3 was surely needed, knock_test.py was my old script from some other project, and I forgot to change it. I have some mixed feelings about using decltype(&funcname). Sure it is good for production code, but it is a demo, and I wanted to show how everything works very explicitly, rather than hiding some logic behind autopointers, etc. But let it be, I will just update the paper, and show both examples.