#include <stdio.h>

char rolling_xor(char *key, char* encrypted_data)
{
  char* v0 = key;
  int v1 = 0;
  char *i = encrypted_data;
  char result;

  for ( ; *i; ++i )
  {
    result = *v0;
    *i ^= *v0++;
    if ( ++v1 == 8 )
    {
      v0 = key;
      v1 = 0;
    }
  }
  return result;
}

int main(){
  char encrypted_data[] =
  {
    0x09, 0x07, 0x11, 0x48, 0x20, 0x73, 0x02, 0x68, 0x2C, 0x67, 
    0x62, 0x02, 0x3E, 0x36, 0x7D, 0x1A, 0x1E, 0x35, 0x1F, 0x07, 
    0x2A, 0x1D, 0x3C, 0x0B, 0x71, 0x25, 0x62, 0x57, 0x7E, 0x30, 
    0x13, 0x3B, 0x71, 0x07, 0x2E, 0x00
  };

  char key[] =
  {
    0x52, 0x4A, 0x4A, 0x33, 0x44, 0x53, 0x43, 0x50, 0x00
  };


  rolling_xor(key, encrypted_data);

  printf("decrypted: %s\n", encrypted_data);

}