Explanation-of-the-code-pppwn.py

+---------------------------------------+
|               Header                  |
|---------------------------------------|
| #!/usr/bin/env python3                |
| # Copyright and License               |
+---------------------------------------+
|          Import Libraries             |    ## Explantation 1
|---------------------------------------|    
| from argparse import ArgumentParser   |
| from scapy.all import *               |
| from scapy.layers.ppp import *        |
| from struct import pack, unpack       |
| from sys import exit                  |
| from time import sleep                |
| from offsets import *                 |
+---------------------------------------+
        |
        v
+---------------------------------------+
|               Constants               |
|---------------------------------------|
|          PPPoE Constants              |    ## Explanation 2
|---------------------------------------|
| PPPOE_TAG_HUNIQUE, PPPOE_TAG_ACOOKIE, |
| PPPOE_CODE_PADI, ...                  |
|---------------------------------------|
|           FreeBSD Constants           |
|---------------------------------------|
| NULL, PAGE_SIZE, ...                  |
|---------------------------------------|
|           FreeBSD Offsets             |
|---------------------------------------|
| TARGET_SIZE, PPPOE_SOFTC_SC_DEST, ... |
+---------------------------------------+
        |
        v
+---------------------------------------+
|            Helper Functions           |
|---------------------------------------|     # Explanation 3
| p8, p16, p16be, p32, p32be, p64, p64be|
+---------------------------------------+
        |          
        v          v---------------------------------------------------------------|
+-----------------------+   +---------------------------------------+              |
|  LcpEchoHandler       |   |             Exploit Class             |              v
|-----------------------|   |---------------------------------------|       # Explanation 4
| __init__              |   | __init__(self, offs, iface, stage1,   |
| handler               |   |          stage2, stage3, stage4)      |
|                       |   | kdlsym(self, ksym)                    |
+-----------------------+   | lcp_negotiation(self)                 |
                            | ipcp_negotiation(self)                |
            |               | ppp_negotation(self)                  |
            v               | build_fake_ifnet(self, fake_ifnet_ptr)|
    Uses AsyncSniffer       | build_overflow_lle(self)              |
                            | build_fake_lle(self, lleak)           |
                            | build_first_rop(self, overflow_ifnet, |
                            |                 lleak)                |
                            | build_second_rop(self, kernel_leak,   |
                            |                  lleak)               |
            |               | execute(self)                         |
            v               | send_padi(self)                       |
                            | send_padr(self, source)               |        # Explanation 5
                            | send_lcp(self, lcp_pkt)               |
                            | send_ipcp(self, ipcp_pkt)             |
                            | recv_lcp(self)                        |
                            | recv_ipcp(self)                       |
                            | ppp_auth(self)                        |
                            | do_exploit(self)                      |
                            +---------------------------------------+

            |                   |                     |
            v                   v                     v
+----------------------------------------------------------+
|                        Relationships                     |
|----------------------------------------------------------|
| Exploit <-----------------------------------> Constants  |       # Explanation 6
| Exploit <-----------------------------------> Functions  |
| LcpEchoHandler <----------------------------> scapy      |
| Exploit <-----------------------------------> offsets    |
+----------------------------------------------------------+
        |
        v
+---------------------------------------+
|       Stage 1: Initial Setup          |
|---------------------------------------|
| Send and receive PADI and PADO packets|     # Explanation 7
| Send and receive PADR and PADS packets|
| Setup PPP connections                 |
+---------------------------------------+
        |
        v
+---------------------------------------+
|        Stage 2: Defeat KASLR          |
|---------------------------------------|
| Defeat KASLR using leak techniques    |     # Explanation 8
| Use leaked address information        |
| to build ROP chains                   |
+---------------------------------------+
        |
        v
+---------------------------------------+
|        Stage 3: Build First ROP       |
|---------------------------------------|
| Build first ROP chain                 |
| Build Second Rop chain                |      # Explanation 9
| Exploit memory leaks                  |
| Create fake data structures           |
+---------------------------------------+
        |
        v
+---------------------------------------+
|        Stage 4: Final Exploitation    |
|---------------------------------------|
| Execute second ROP chain              |      # Explanation 10
| Run malicious instructions            |
| Complete the exploit                  |
+---------------------------------------+

Explanation STAGES :

Explanation 1:

This section imports the necessary libraries and defines the environment for the script.

Explanation 2:

This section defines constants related to PPPoE and FreeBSD that are used throughout the exploit.

Explanation 3:

These functions assist with data manipulation and packing/unpacking of values for network communication and memory operations.

Explanation 4:

This class handles LCP echo requests and responses using an asynchronous sniffer from the scapy library.

Explanation 5:

This class manages the core exploit functionality, including network packet exchanges and memory exploitation processes.

Explanation 6:

This section illustrates the interconnections between different components and classes within the script.

Explanation 7:

This stage establishes initial PPPoE connections by exchanging discovery packets (PADI, PADO, PADR, PADS) to set up a valid PPP session.

Explanation 8:

This stage defeats Kernel Address Space Layout Randomization (KASLR) by using information leaks to discover kernel addresses, which are essential for building return-oriented programming (ROP) chains.

Explanation 9:

This stage constructs the initial ROP chain, leveraging memory leaks to manipulate kernel structures and set up the exploit environment.

Explanation 10:

The final stage executes the second ROP chain to perform the intended malicious actions, thereby completing the exploit.

//thanks to all developers on the sence//