虚拟内存探究 -- 第二篇:Python 字节

#!/usr/bin/env python3
'''
Prints a b"string" (bytes object), reads a char from stdin
and prints the same (or not :)) string again
'''

import sys

s = b"Holberton"
print(s)
sys.stdin.read(1)
print(s)

julien@holberton:~/holberton/w/hackthevm1$ python3
Python 3.4.3 (default, Nov 17 2016, 01:08:31) 
[GCC 4.8.4] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> s = "Betty"
>>> type(s)
<class 'str'>
>>> s = b"Betty"
>>> type(s)
<class 'bytes'>
>>> quit()

julien@holberton:~/holberton/w/hackthevm1$ ./main.py 
b'Holberton'

julien@holberton:~/holberton/w/hackthevm1$ ps aux | grep main.py | grep -v grep
julien     3929  0.0  0.7  31412  7848 pts/0    S+   15:10   0:00 python3 ./main.py
julien@holberton:~/holberton/w/hackthevm1$ sudo ./read_write_heap.py 3929 Holberton "~ Betty ~"
[*] maps: /proc/3929/maps
[*] mem: /proc/3929/mem
[*] Found [heap]:
    pathname = [heap]
    addresses = 022dc000-023c6000
    permisions = rw-p
    offset = 00000000
    inode = 0
    Addr start [22dc000] | end [23c6000]
[*] Found 'Holberton' at 8e192
[*] Writing '~ Betty ~' at 236a192
julien@holberton:~/holberton/w/hackthevm1$ 

b'Holberton'
julien@holberton:~/holberton/w/hackthevm1$

julien@holberton:~/holberton/w/hackthevm1$ ./main.py 
b'Holberton'

julien@holberton:~/holberton/w/hackthevm1$ ps aux | grep main.py | grep -v grep
julien     4051  0.1  0.7  31412  7832 pts/0    S+   15:53   0:00 python3 ./main.py
julien@holberton:~/holberton/w/hackthevm1$ sudo ./read_write_heap.py 4051 Holberton "~ Betty ~"
[*] maps: /proc/4051/maps
[*] mem: /proc/4051/mem
[*] Found [heap]:
    pathname = [heap]
    addresses = 00bf4000-00cde000
    permisions = rw-p
    offset = 00000000
    inode = 0
    Addr start [bf4000] | end [cde000]
[*] Found 'Holberton' at 8e162
[*] Writing '~ Betty ~' at c82162
julien@holberton:~/holberton/w/hackthevm1$ sudo ./read_write_heap.py 4051 Holberton "~ Betty ~"
[*] maps: /proc/4051/maps
[*] mem: /proc/4051/mem
[*] Found [heap]:
    pathname = [heap]
    addresses = 00bf4000-00cde000
    permisions = rw-p
    offset = 00000000
    inode = 0
    Addr start [bf4000] | end [cde000]
Can't find 'Holberton'
julien@holberton:~/holberton/w/hackthevm1$ 

#!/usr/bin/env python3
'''
Locates and replaces the first occurrence of a string in the stack
of a process

Usage: ./read_write_stack.py PID search_string replace_by_string
Where:
- PID is the pid of the target process
- search_string is the ASCII string you are looking to overwrite
- replace_by_string is the ASCII string you want to replace
search_string with
'''

import sys

def print_usage_and_exit():
    print('Usage: {} pid search write'.format(sys.argv[0]))
    sys.exit(1)

# check usage
if len(sys.argv) != 4:
    print_usage_and_exit()

# get the pid from args
pid = int(sys.argv[1])
if pid <= 0:
    print_usage_and_exit()
search_string = str(sys.argv[2])
if search_string  == "":
    print_usage_and_exit()
write_string = str(sys.argv[3])
if search_string  == "":
    print_usage_and_exit()

# open the maps and mem files of the process
maps_filename = "/proc/{}/maps".format(pid)
print("[*] maps: {}".format(maps_filename))
mem_filename = "/proc/{}/mem".format(pid)
print("[*] mem: {}".format(mem_filename))

# try opening the maps file
try:
    maps_file = open('/proc/{}/maps'.format(pid), 'r')
except IOError as e:
    print("[ERROR] Can not open file {}:".format(maps_filename))
    print("        I/O error({}): {}".format(e.errno, e.strerror))
    sys.exit(1)

for line in maps_file:
    sline = line.split(' ')
    # check if we found the stack
    if sline[-1][:-1] != "[stack]":
        continue
    print("[*] Found [stack]:")

    # parse line
    addr = sline[0]
    perm = sline[1]
    offset = sline[2]
    device = sline[3]
    inode = sline[4]
    pathname = sline[-1][:-1]
    print("\tpathname = {}".format(pathname))
    print("\taddresses = {}".format(addr))
    print("\tpermisions = {}".format(perm))
    print("\toffset = {}".format(offset))
    print("\tinode = {}".format(inode))

    # check if there is read and write permission
    if perm[0] != 'r' or perm[1] != 'w':
        print("[*] {} does not have read/write permission".format(pathname))
        maps_file.close()
        exit(0)

    # get start and end of the stack in the virtual memory
    addr = addr.split("-")
    if len(addr) != 2: # never trust anyone, not even your OS :)
        print("[*] Wrong addr format")
        maps_file.close()
        exit(1)
    addr_start = int(addr[0], 16)
    addr_end = int(addr[1], 16)
    print("\tAddr start [{:x}] | end [{:x}]".format(addr_start, addr_end))

    # open and read mem
    try:
        mem_file = open(mem_filename, 'rb+')
    except IOError as e:
        print("[ERROR] Can not open file {}:".format(mem_filename))
        print("        I/O error({}): {}".format(e.errno, e.strerror))
        maps_file.close()
        exit(1)

    # read stack
    mem_file.seek(addr_start)
    stack = mem_file.read(addr_end - addr_start)

    # find string
    try:
        i = stack.index(bytes(search_string, "ASCII"))
    except Exception:
        print("Can't find '{}'".format(search_string))
        maps_file.close()
        mem_file.close()
        exit(0)
    print("[*] Found '{}' at {:x}".format(search_string, i))

    # write the new stringprint("[*] Writing '{}' at {:x}".format(write_string, addr_start + i))
    mem_file.seek(addr_start + i)
    mem_file.write(bytes(write_string, "ASCII"))

    # close filesmaps_file.close()
    mem_file.close()

    # there is only one stack in our example
    break

julien@holberton:~/holberton/w/hackthevm1$ ./main.py
b'Holberton'

julien@holberton:~/holberton/w/hackthevm1$ ps aux | grep main.py | grep -v grep
julien     4124  0.2  0.7  31412  7848 pts/0    S+   16:10   0:00 python3 ./main.py
julien@holberton:~/holberton/w/hackthevm1$ sudo ./read_write_stack.py 4124 Holberton "~ Betty ~"
[sudo] password for julien: 
[*] maps: /proc/4124/maps
[*] mem: /proc/4124/mem
[*] Found [stack]:
    pathname = [stack]
    addresses = 7fff2997e000-7fff2999f000
    permisions = rw-p
    offset = 00000000
    inode = 0
    Addr start [7fff2997e000] | end [7fff2999f000]
Can't find 'Holberton'
julien@holberton:~/holberton/w/hackthevm1$ 

#!/usr/bin/env python3
'''
Prints:
- the address of the bytes object
- a b"string" (bytes object)
reads a char from stdin
and prints the same (or not :)) string again
'''

import sys

s = b"Holberton"
print(hex(id(s)))
print(s)
sys.stdin.read(1)
print(s)

julien@holberton:~/holberton/w/hackthevm1$ ./main_id.py
0x7f343f010210
b'Holberton'

julien@holberton:/usr/include/python3.4$ ps aux | grep main_id.py | grep -v grep
julien     4344  0.0  0.7  31412  7856 pts/0    S+   16:53   0:00 python3 ./main_id.py
julien@holberton:/usr/include/python3.4$ cat /proc/4344/maps
00400000-006fa000 r-xp 00000000 08:01 655561                             /usr/bin/python3.4
008f9000-008fa000 r--p 002f9000 08:01 655561                             /usr/bin/python3.4
008fa000-00986000 rw-p 002fa000 08:01 655561                             /usr/bin/python3.4
00986000-009a2000 rw-p 00000000 00:00 0 
021ba000-022a4000 rw-p 00000000 00:00 0                                  [heap]
7f343d797000-7f343de79000 r--p 00000000 08:01 663747                     /usr/lib/locale/locale-archive
7f343de79000-7f343df7e000 r-xp 00000000 08:01 136303                     /lib/x86_64-linux-gnu/libm-2.19.so
7f343df7e000-7f343e17d000 ---p 00105000 08:01 136303                     /lib/x86_64-linux-gnu/libm-2.19.so
7f343e17d000-7f343e17e000 r--p 00104000 08:01 136303                     /lib/x86_64-linux-gnu/libm-2.19.so
7f343e17e000-7f343e17f000 rw-p 00105000 08:01 136303                     /lib/x86_64-linux-gnu/libm-2.19.so
7f343e17f000-7f343e197000 r-xp 00000000 08:01 136416                     /lib/x86_64-linux-gnu/libz.so.1.2.8
7f343e197000-7f343e396000 ---p 00018000 08:01 136416                     /lib/x86_64-linux-gnu/libz.so.1.2.8
7f343e396000-7f343e397000 r--p 00017000 08:01 136416                     /lib/x86_64-linux-gnu/libz.so.1.2.8
7f343e397000-7f343e398000 rw-p 00018000 08:01 136416                     /lib/x86_64-linux-gnu/libz.so.1.2.8
7f343e398000-7f343e3bf000 r-xp 00000000 08:01 136275                     /lib/x86_64-linux-gnu/libexpat.so.1.6.0
7f343e3bf000-7f343e5bf000 ---p 00027000 08:01 136275                     /lib/x86_64-linux-gnu/libexpat.so.1.6.0
7f343e5bf000-7f343e5c1000 r--p 00027000 08:01 136275                     /lib/x86_64-linux-gnu/libexpat.so.1.6.0
7f343e5c1000-7f343e5c2000 rw-p 00029000 08:01 136275                     /lib/x86_64-linux-gnu/libexpat.so.1.6.0
7f343e5c2000-7f343e5c4000 r-xp 00000000 08:01 136408                     /lib/x86_64-linux-gnu/libutil-2.19.so
7f343e5c4000-7f343e7c3000 ---p 00002000 08:01 136408                     /lib/x86_64-linux-gnu/libutil-2.19.so
7f343e7c3000-7f343e7c4000 r--p 00001000 08:01 136408                     /lib/x86_64-linux-gnu/libutil-2.19.so
7f343e7c4000-7f343e7c5000 rw-p 00002000 08:01 136408                     /lib/x86_64-linux-gnu/libutil-2.19.so
7f343e7c5000-7f343e7c8000 r-xp 00000000 08:01 136270                     /lib/x86_64-linux-gnu/libdl-2.19.so
7f343e7c8000-7f343e9c7000 ---p 00003000 08:01 136270                     /lib/x86_64-linux-gnu/libdl-2.19.so
7f343e9c7000-7f343e9c8000 r--p 00002000 08:01 136270                     /lib/x86_64-linux-gnu/libdl-2.19.so
7f343e9c8000-7f343e9c9000 rw-p 00003000 08:01 136270                     /lib/x86_64-linux-gnu/libdl-2.19.so
7f343e9c9000-7f343eb83000 r-xp 00000000 08:01 136253                     /lib/x86_64-linux-gnu/libc-2.19.so
7f343eb83000-7f343ed83000 ---p 001ba000 08:01 136253                     /lib/x86_64-linux-gnu/libc-2.19.so
7f343ed83000-7f343ed87000 r--p 001ba000 08:01 136253                     /lib/x86_64-linux-gnu/libc-2.19.so
7f343ed87000-7f343ed89000 rw-p 001be000 08:01 136253                     /lib/x86_64-linux-gnu/libc-2.19.so
7f343ed89000-7f343ed8e000 rw-p 00000000 00:00 0 
7f343ed8e000-7f343eda7000 r-xp 00000000 08:01 136373                     /lib/x86_64-linux-gnu/libpthread-2.19.so
7f343eda7000-7f343efa6000 ---p 00019000 08:01 136373                     /lib/x86_64-linux-gnu/libpthread-2.19.so
7f343efa6000-7f343efa7000 r--p 00018000 08:01 136373                     /lib/x86_64-linux-gnu/libpthread-2.19.so
7f343efa7000-7f343efa8000 rw-p 00019000 08:01 136373                     /lib/x86_64-linux-gnu/libpthread-2.19.so
7f343efa8000-7f343efac000 rw-p 00000000 00:00 0 
7f343efac000-7f343efcf000 r-xp 00000000 08:01 136229                     /lib/x86_64-linux-gnu/ld-2.19.so
7f343f000000-7f343f1b6000 rw-p 00000000 00:00 0 
7f343f1c5000-7f343f1cc000 r--s 00000000 08:01 918462                     /usr/lib/x86_64-linux-gnu/gconv/gconv-modules.cache
7f343f1cc000-7f343f1ce000 rw-p 00000000 00:00 0 
7f343f1ce000-7f343f1cf000 r--p 00022000 08:01 136229                     /lib/x86_64-linux-gnu/ld-2.19.so
7f343f1cf000-7f343f1d0000 rw-p 00023000 08:01 136229                     /lib/x86_64-linux-gnu/ld-2.19.so
7f343f1d0000-7f343f1d1000 rw-p 00000000 00:00 0 
7ffccf1fd000-7ffccf21e000 rw-p 00000000 00:00 0                          [stack]
7ffccf23c000-7ffccf23e000 r--p 00000000 00:00 0                          [vvar]
7ffccf23e000-7ffccf240000 r-xp 00000000 00:00 0                          [vdso]
ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0                  [vsyscall]
julien@holberton:/usr/include/python3.4$ 

7f343f000000-7f343f1b6000 rw-p 00000000 00:00 0

typedef struct {
    PyObject_VAR_HEAD
    Py_hash_t ob_shash;
    char ob_sval[1];

    /* Invariants:
     *     ob_sval contains space for 'ob_size+1' elements.
     *     ob_sval[ob_size] == 0.
     *     ob_shash is the hash of the string or -1 if not computed yet.
     */
} PyBytesObject;

void print_python_bytes(PyObject *p);

/* Object and type object interface */

/*
Objects are structures allocated on the heap.  Special rules apply to
the use of objects to ensure they are properly garbage-collected.
Objects are never allocated statically or on the stack; they must be
...
*/

/*
...
Objects do not float around in memory; once allocated an object keeps
the same size and address.  Objects that must hold variable-size data
...
*/

/*
...
Objects are always accessed through pointers of the type 'PyObject *'.
The type 'PyObject' is a structure that only contains the reference count
and the type pointer.  The actual memory allocated for an object
contains other data that can only be accessed after casting the pointer
to a pointer to a longer structure type.  This longer type must start
with the reference count and type fields; the macro PyObject_HEAD should be
used for this (to accommodate for future changes).  The implementation
of a particular object type can cast the object pointer to the proper
type and back.
...
*/

/* PyObject_VAR_HEAD defines the initial segment of all variable-size
 * container objects.  These end with a declaration of an array with 1
 * element, but enough space is malloc'ed so that the array actually
 * has room for ob_size elements.  Note that ob_size is an element count,
 * not necessarily a byte count.
 */
#define PyObject_VAR_HEAD      PyVarObject ob_base;
#define Py_INVALID_SIZE (Py_ssize_t)-1

/* Nothing is actually declared to be a PyObject, but every pointer to
 * a Python object can be cast to a PyObject*.  This is inheritance built
 * by hand.  Similarly every pointer to a variable-size Python object can,
 * in addition, be cast to PyVarObject*.
 */
typedef struct _object {
    _PyObject_HEAD_EXTRA
    Py_ssize_t ob_refcnt;
    struct _typeobject *ob_type;
} PyObject;

typedef struct {
    PyObject ob_base;
    Py_ssize_t ob_size; /* Number of items in variable part */
} PyVarObject;

#include "Python.h"

/**
 * print_python_bytes - prints info about a Python 3 bytes object
 * @p: a pointer to a Python 3 bytes object
 * 
 * Return: Nothing
 */
void print_python_bytes(PyObject *p)
{
     /* The pointer with the correct type.*/
     PyBytesObject *s;
     unsigned int i;

     printf("[.] bytes object info\n");
     /* casting the PyObject pointer to a PyBytesObject pointer */
     s = (PyBytesObject *)p;
     /* never trust anyone, check that this is actually
        a PyBytesObject object. */
     if (s && PyBytes_Check(s))
     {
          /* a pointer holds the memory address of the first byte
         of the data it points to */
          printf("  address of the object: %p\n", (void *)s);
          /* op_size is in the ob_base structure, of type PyVarObject. */
          printf("  size: %ld\n", s->ob_base.ob_size);
          /* ob_sval is the array of bytes, ending with the value 0:
         ob_sval[ob_size] == 0 */
          printf("  trying string: %s\n", s->ob_sval);
          printf("  address of the data: %p\n", (void *)(s->ob_sval));
          printf("  bytes:");
          /* printing each byte at a time, in case this is not
         a "string". bytes doesn't have to be strings.
         ob_sval contains space for 'ob_size+1' elements.
         ob_sval[ob_size] == 0. */
          for (i = 0; i < s->ob_base.ob_size + 1; i++)
          {
               printf(" %02x", s->ob_sval[i] & 0xff);
          }
          printf("\n");
     }
     /* if this is not a PyBytesObject print an error message */
     else
     {
          fprintf(stderr, "  [ERROR] Invalid Bytes Object\n");
     }
}

gcc -Wall -Wextra -pedantic -Werror -std=c99 -shared -Wl,-soname,libPython.so -o libPython.so -fPIC -I/usr/include/python3.4 bytes.c

import ctypes

lib = ctypes.CDLL('./libPython.so')
lib.print_python_bytes.argtypes = [ctypes.py_object]

lib.print_python_bytes(s)

#!/usr/bin/env python3
'''
Prints:
- the address of the bytes object
- a b"string" (bytes object)
- information about the bytes object
And then:
- reads a char from stdin
- prints the same (or not :)) information again
'''

import sys
import ctypes

lib = ctypes.CDLL('./libPython.so')
lib.print_python_bytes.argtypes = [ctypes.py_object]

s = b"Holberton"
print(hex(id(s)))
print(s)
lib.print_python_bytes(s)

sys.stdin.read(1)

print(hex(id(s)))
print(s)
lib.print_python_bytes(s)

julien@holberton:~/holberton/w/hackthevm1$ ./main_bytes.py 
0x7f04d721b210
b'Holberton'
[.] bytes object info
  address of the object: 0x7f04d721b210
  size: 9
  trying string: Holberton
  address of the data: 0x7f04d721b230
  bytes: 48 6f 6c 62 65 72 74 6f 6e 00

#!/usr/bin/env python3
'''
Locates and replaces (if we have permission) all occurrences of
an ASCII string in the entire virtual memory of a process.

Usage: ./rw_all.py PID search_string replace_by_string
Where:
- PID is the pid of the target process
- search_string is the ASCII string you are looking to overwrite
- replace_by_string is the ASCII string you want to replace
search_string with
'''

import sys

def print_usage_and_exit():
    print('Usage: {} pid search write'.format(sys.argv[0]))
    exit(1)

# check usage
if len(sys.argv) != 4:
    print_usage_and_exit()

# get the pid from args
pid = int(sys.argv[1])
if pid <= 0:
    print_usage_and_exit()
search_string = str(sys.argv[2])
if search_string  == "":
    print_usage_and_exit()
write_string = str(sys.argv[3])
if search_string  == "":
    print_usage_and_exit()

# open the maps and mem files of the process
maps_filename = "/proc/{}/maps".format(pid)
print("[*] maps: {}".format(maps_filename))
mem_filename = "/proc/{}/mem".format(pid)
print("[*] mem: {}".format(mem_filename))

# try opening the file
try:
    maps_file = open('/proc/{}/maps'.format(pid), 'r')
except IOError as e:
    print("[ERROR] Can not open file {}:".format(maps_filename))
    print("        I/O error({}): {}".format(e.errno, e.strerror))
    exit(1)

for line in maps_file:
    # print the name of the memory region
    sline = line.split(' ')
    name = sline[-1][:-1];
    print("[*] Searching in {}:".format(name))

    # parse line
    addr = sline[0]
    perm = sline[1]
    offset = sline[2]
    device = sline[3]
    inode = sline[4]
    pathname = sline[-1][:-1]

    # check if there are read and write permissions
    if perm[0] != 'r' or perm[1] != 'w':
        print("\t[\x1B[31m!\x1B[m] {} does not have read/write permissions ({})".format(pathname, perm))
        continue

    print("\tpathname = {}".format(pathname))
    print("\taddresses = {}".format(addr))
    print("\tpermisions = {}".format(perm))
    print("\toffset = {}".format(offset))
    print("\tinode = {}".format(inode))

    # get start and end of the memoy region
    addr = addr.split("-")
    if len(addr) != 2: # never trust anyone
        print("[*] Wrong addr format")
        maps_file.close()
        exit(1)
    addr_start = int(addr[0], 16)
    addr_end = int(addr[1], 16)
    print("\tAddr start [{:x}] | end [{:x}]".format(addr_start, addr_end))

    # open and read the memory region
    try:
        mem_file = open(mem_filename, 'rb+')
    except IOError as e:
        print("[ERROR] Can not open file {}:".format(mem_filename))
        print("        I/O error({}): {}".format(e.errno, e.strerror))
        maps_file.close()

    # read the memory region
    mem_file.seek(addr_start)
    region = mem_file.read(addr_end - addr_start)

    # find string
    nb_found = 0;
    try:
        i = region.index(bytes(search_string, "ASCII"))
        while (i):
            print("\t[\x1B[32m:)\x1B[m] Found '{}' at {:x}".format(search_string, i))
            nb_found = nb_found + 1
            # write the new string
        print("\t[:)] Writing '{}' at {:x}".format(write_string, addr_start + i))
            mem_file.seek(addr_start + i)
            mem_file.write(bytes(write_string, "ASCII"))
            mem_file.flush()

            # update our buffer
        region.write(bytes(write_string, "ASCII"), i)

            i = region.index(bytes(search_string, "ASCII"))
    except Exception:
        if nb_found == 0:
            print("\t[\x1B[31m:(\x1B[m] Can't find '{}'".format(search_string))
    mem_file.close()

# close files
maps_file.close()

julien@holberton:~/holberton/w/hackthevm1$ ./main_bytes.py 
0x7f37f1e01210
b'Holberton'
[.] bytes object info
  address of the object: 0x7f37f1e01210
  size: 9
  trying string: Holberton
  address of the data: 0x7f37f1e01230
  bytes: 48 6f 6c 62 65 72 74 6f 6e 00

julien@holberton:~/holberton/w/hackthevm1$ ps aux | grep main_bytes.py | grep -v grep
julien     4713  0.0  0.8  37720  8208 pts/0    S+   18:48   0:00 python3 ./main_bytes.py
julien@holberton:~/holberton/w/hackthevm1$ sudo ./rw_all.py 4713 Holberton "~ Betty ~"
[*] maps: /proc/4713/maps
[*] mem: /proc/4713/mem
[*] Searching in /usr/bin/python3.4:
    [!] /usr/bin/python3.4 does not have read/write permissions (r-xp)
...
[*] Searching in [heap]:
    pathname = [heap]
    addresses = 00e26000-00f11000
    permisions = rw-p
    offset = 00000000
    inode = 0
    Addr start [e26000] | end [f11000]
    [:)] Found 'Holberton' at 8e422
    [:)] Writing '~ Betty ~' at eb4422
...
[*] Searching in :
    pathname = 
    addresses = 7f37f1df1000-7f37f1fa7000
    permisions = rw-p
    offset = 00000000
    inode = 0
    Addr start [7f37f1df1000] | end [7f37f1fa7000]
    [:)] Found 'Holberton' at 10230
    [:)] Writing '~ Betty ~' at 7f37f1e01230
...
[*] Searching in [stack]:
    pathname = [stack]
    addresses = 7ffdc3d0c000-7ffdc3d2d000
    permisions = rw-p
    offset = 00000000
    inode = 0
    Addr start [7ffdc3d0c000] | end [7ffdc3d2d000]
    [:(] Can't find 'Holberton'
...
julien@holberton:~/holberton/w/hackthevm1$ 

julien@holberton:~/holberton/w/hackthevm1$ ./main_bytes.py 
0x7f37f1e01210
b'Holberton'
[.] bytes object info
  address of the object: 0x7f37f1e01210
  size: 9
  trying string: Holberton
  address of the data: 0x7f37f1e01230
  bytes: 48 6f 6c 62 65 72 74 6f 6e 00

0x7f37f1e01210
b'~ Betty ~'
[.] bytes object info
  address of the object: 0x7f37f1e01210
  size: 9
  trying string: ~ Betty ~
  address of the data: 0x7f37f1e01230
  bytes: 7e 20 42 65 74 74 79 20 7e 00
julien@holberton:~/holberton/w/hackthevm1$