# CS6332: List of useful tools for the class ## vim editor Vim is a powerful text editor. The combination of multiple commands makes your life easier. I make a very introduction. ### Basic usage Let's open a file with vim in terminal. `vim <some file>` There are some modes. Normal mode: You can move. - Move - ↓: `j` - ↑: `k` - →: `l` - ←: `h` You can delete too. - Delete - character: `x` - word: `dw` or `de` - `dw`: until the next word ```txt <cursor>word1␣word2␣word3 ↓ <cursor>word2␣word3 ``` - `de`: until the current word ```txt <cursor>word1␣word2␣word3 ↓ <cursor>␣word2␣word3 ``` - line: `dd` Edit mode: Do you want to write something? Type one of `o`, `O`, `i`, or `a`. Now, you can edit! ```txt <O> AB<i>C<cursor>D<a>E <o> ``` You want to return back to the normal mode? Type `ESC`. Are you fed up with this editor? In the normal mode, type `:x` or `:wq` to save (write) and quit. If you don't want to save, enter `:q!`. ### What's more A good way to get started is to watch this video. <iframe width="560" height="315" src="https://www.youtube.com/embed/13gNtgqzzmM?si=7FydcL0vcoxSbaAK" title="YouTube video player" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share" allowfullscreen></iframe> - Or, type `vimtutor` on terminal. - Or, visit online "vim-cheatsheet" sites. - Or, read [MIT missing semester](https://missing.csail.mit.edu/2020/editors/) ## tmux ### Basic usage `tmux` starts a new tmux sessions A session has windows, and a window has panes. - Session - Detach: `C-b d` - Re-enter the last detached session: `tmux a` (from terminal) - Window - create a new window: `C-b c` (`C-b` means type `control` key and `b` simultaneously) - move to the window 0: `C-b 0` - move to the window <num>: `C-b <num>` - delete a window: `C-b &` - Pane - create a new pane vertically: `C-b %` - create a new pane horizontally: `C-b "` - delete: `C-b x` - move to a next pane: `C-b o` Hey! How can I scroll up and down? Use `C-b [` (copy-mode). Video versions: <iframe src="https://capture.dropbox.com/embed/rBeyb4bMtRRFnRnx?source=copy-embed" width="560" height="315" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe> <iframe src="https://capture.dropbox.com/embed/mR5ERlKzVDUDIgH5?source=copy-embed" width="560" height="315" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe> <iframe src="https://capture.dropbox.com/embed/pfV3Bg8owevRH9Zf?source=copy-embed" width="560" height="315" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe> ### How to customize Edit `~/.tmux.conf`. I recommend adding these lines at least. ```conf set -g default-terminal "screen-256color" # colorful tmux setw -g mode-keys vi # use vim in copy mode ``` ### What's more - [Cheatsheet](https://tmuxcheatsheet.com/) - [MIT missing semester](https://missing.csail.mit.edu/2020/command-line/) ## pwntools pwntools is a Python CTF framework. When you analyze a binary code in this course, this tool will be your friend. ### Basic usage ```python= from pwn import * context.clear(arch="amd64") # set cpu architecture context.terminal = ["tmux", "splitw", "-h"] # set how it opens a tmux session ``` This imports a lot of functionality into the global namespace. You can now assemble, disassemble, pack, unpack, and many other things with a single function. [^pwn-intro] [^pwn-intro]: https://docs.pwntools.com/en/stable/intro.html The workflow to exploit a program with I/O will be like this. ```python= # You will be given a binary, `bin_file` p = process(bin_file) # spawn bin_file process print(p.sendline(b"some random words to exploit the program")) # p.send(b"string"): p.sendline(b"string") without a newline print(p.recvline()) # output the process stdout # p.recv(numb=4096, timeout=default): receive up to `numb` characters ``` Do you want to debug it? Sure. You can use `gdb` with pwntools. ```python= p = process(bin_file) # start a process # You can write gdb script with an optional argument. Start gdb process and let it monitor `p` process! gdb.attach(p, gdbscript=""" break main """) p.sendline(b"hello") # you can send a line as before p.recvline() # you can receive a line as before p.interactive() # you can dive into gdb from here ``` - Write `.py` file - Run it on `tmux` - Debug it! Demo: <iframe src="https://capture.dropbox.com/embed/afo3aUnZlxpBLHAa?source=copy-embed" width="560" height="315" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe> ### What's more [official documents](https://docs.pwntools.com/en/stable/) ## Regex Regular expression. We use it to extract some patterns. You often need to get a specific type of input or output in binary.  [pdf version](https://images.datacamp.com/image/upload/v1665049611/Marketing/Blog/Regular_Expressions_Cheat_Sheet.pdf) ### What's more You can see if your pattern matches a string in the site below. <https://regex101.com/> ###### tags: `cs6332`,`candl`,`course`