connecting_file.py

import ipaddress
import os
import socket
import subprocess


def parse_ip_port(c):
    ip_h, port_h = c.split(":")
    return str(ipaddress.IPv4Address(socket.htonl(int(ip_h, 16)))), int(port_h, 16)

def get_socket_inode(addr_tuple):
    tcp_f = open("/proc/net/tcp")
    tcp_f.readline()
    for line in tcp_f:
        columns = line.strip().split()
        remote_address = parse_ip_port(columns[1])
        inode = int(columns[9])
        if remote_address == addr_tuple:
            return inode

def get_inode_pid(inode):
    proc_l = os.listdir("/proc")
    for proc_num in proc_l:
        if not proc_num.isdecimal():
            continue
        pid = int(proc_num)
        try:
            fd_l = os.listdir(f"/proc/{pid}/fd")
        except (PermissionError, FileNotFoundError):
            continue
        for fd_num in fd_l:
            try:
                fd_stat = os.stat(f"/proc/{pid}/fd/{fd_num}")
            except FileNotFoundError:
                continue
            if fd_stat.st_ino == inode:
                return pid

def get_pid_path(pid):
    return os.readlink(f"/proc/{pid}/exe")

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEPORT, 1)
s.bind(("127.0.0.1", 2222))
print("Connect with 'telnet 127.0.0.1 2222'")
s.listen()
while True:
    conn, peer = s.accept()
    print("Peer address", peer)
    inode = get_socket_inode(peer)
    print("Inode", inode)
    pid = get_inode_pid(inode)
    print("PID", pid)
    path = get_pid_path(pid)
    print("Path", path)
    subprocess.run(["file", path])
    conn.close()