如何在 Debian 中配置 Tripewire IDS
安裝和配置
tripwire 在 Debian VM 中的安裝如下。
# apt-get install tripwire
安裝中,tripwire 會有下面的配置提示。
站點密鑰創建
tripwire 需要一個站點口令(site passphrase)來加密 tripwire 的配置文件 tw.cfg 和策略文件 tw.pol。tripewire 使用指定的密碼加密兩個文件。一個 tripewire 實例必須指定站點口令。
本地密鑰口令
本地口令用來保護 tripwire 資料庫和報告文件。本地密鑰用於阻止非授權的 tripewire 資料庫修改。
tripwire 配置路徑
tripewire 配置存儲在 /etc/tripwire/twcfg.txt。它用於生成加密的配置文件 tw.cfg。
tripwire 策略路徑
tripwire 在 /etc/tripwire/twpol.txt 中保存策略文件。它用於生成加密的策略文件 tw.pol。
安裝完成後如下圖所示。
tripwire 配置文件 (twcfg.txt)
tripewire 配置文件(twcfg.txt)細節如下圖所示。加密策略文件(tw.pol)、站點密鑰(site.key)和本地密鑰(hostname-local.key)在後面展示。
ROOT =/usr/sbin
POLFILE =/etc/tripwire/tw.pol
DBFILE =/var/lib/tripwire/$(HOSTNAME).twd
REPORTFILE =/var/lib/tripwire/report/$(HOSTNAME)-$(DATE).twr
SITEKEYFILE =/etc/tripwire/site.key
LOCALKEYFILE =/etc/tripwire/$(HOSTNAME)-local.key
EDITOR =/usr/bin/editor
LATEPROMPTING =false
LOOSEDIRECTORYCHECKING =false
MAILNOVIOLATIONS =true
EMAILREPORTLEVEL =3
REPORTLEVEL =3
SYSLOGREPORTING =true
MAILMETHOD =SMTP
SMTPHOST =localhost
SMTPPORT =25
TEMPDIRECTORY =/tmp
tripwire 策略配置
在生成基礎資料庫之前先配置 tripwire 配置。有必要經用一些策略如 /dev、 /proc 、/root/mail 等。詳細的 twpol.txt 策略文件如下所示。
@@section GLOBAL
TWBIN = /usr/sbin;
TWETC = /etc/tripwire;
TWVAR = /var/lib/tripwire;
#
# File System Definitions
#
@@section FS
#
# First, some variables to make configuration easier
#
SEC_CRIT = $(IgnoreNone)-SHa ; # Critical files that cannot change
SEC_BIN = $(ReadOnly) ; # Binaries that should not change
SEC_CONFIG = $(Dynamic) ; # Config files that are changed
# infrequently but accessed
# often
SEC_LOG = $(Growing) ; # Files that grow, but that
# should never change ownership
SEC_INVARIANT = +tpug ; # Directories that should never
# change permission or ownership
SIG_LOW = 33 ; # Non-critical files that are of
# minimal security impact
SIG_MED = 66 ; # Non-critical files that are of
# significant security impact
SIG_HI = 100 ; # Critical files that are
# significant points of
# vulnerability
#
# tripwire Binaries
#
(
rulename = "tripwire Binaries",
severity = $(SIG_HI)
)
{
$(TWBIN)/siggen -> $(SEC_BIN) ;
$(TWBIN)/tripwire -> $(SEC_BIN) ;
$(TWBIN)/twadmin -> $(SEC_BIN) ;
$(TWBIN)/twprint -> $(SEC_BIN) ;
}
{
/boot -> $(SEC_CRIT) ;
/lib/modules -> $(SEC_CRIT) ;
}
(
rulename = "Boot Scripts",
severity = $(SIG_HI)
)
{
/etc/init.d -> $(SEC_BIN) ;
#/etc/rc.boot -> $(SEC_BIN) ;
/etc/rcS.d -> $(SEC_BIN) ;
/etc/rc0.d -> $(SEC_BIN) ;
/etc/rc1.d -> $(SEC_BIN) ;
/etc/rc2.d -> $(SEC_BIN) ;
/etc/rc3.d -> $(SEC_BIN) ;
/etc/rc4.d -> $(SEC_BIN) ;
/etc/rc5.d -> $(SEC_BIN) ;
/etc/rc6.d -> $(SEC_BIN) ;
}
(
rulename = "Root file-system executables",
severity = $(SIG_HI)
)
{
/bin -> $(SEC_BIN) ;
/sbin -> $(SEC_BIN) ;
}
#
# Critical Libraries
#
(
rulename = "Root file-system libraries",
severity = $(SIG_HI)
)
{
/lib -> $(SEC_BIN) ;
}
#
# Login and Privilege Raising Programs
#
(
rulename = "Security Control",
severity = $(SIG_MED)
)
{
/etc/passwd -> $(SEC_CONFIG) ;
/etc/shadow -> $(SEC_CONFIG) ;
}
{
#/var/lock -> $(SEC_CONFIG) ;
#/var/run -> $(SEC_CONFIG) ; # daemon PIDs
/var/log -> $(SEC_CONFIG) ;
}
# These files change the behavior of the root account
(
rulename = "Root config files",
severity = 100
)
{
/root -> $(SEC_CRIT) ; # Catch all additions to /root
#/root/mail -> $(SEC_CONFIG) ;
#/root/Mail -> $(SEC_CONFIG) ;
/root/.xsession-errors -> $(SEC_CONFIG) ;
#/root/.xauth -> $(SEC_CONFIG) ;
#/root/.tcshrc -> $(SEC_CONFIG) ;
#/root/.sawfish -> $(SEC_CONFIG) ;
#/root/.pinerc -> $(SEC_CONFIG) ;
#/root/.mc -> $(SEC_CONFIG) ;
#/root/.gnome_private -> $(SEC_CONFIG) ;
#/root/.gnome-desktop -> $(SEC_CONFIG) ;
#/root/.gnome -> $(SEC_CONFIG) ;
#/root/.esd_auth -> $(SEC_CONFIG) ;
# /root/.elm -> $(SEC_CONFIG) ;
#/root/.cshrc -> $(SEC_CONFIG) ;
#/root/.bashrc -> $(SEC_CONFIG) ;
#/root/.bash_profile -> $(SEC_CONFIG) ;
# /root/.bash_logout -> $(SEC_CONFIG) ;
#/root/.bash_history -> $(SEC_CONFIG) ;
#/root/.amandahosts -> $(SEC_CONFIG) ;
#/root/.addressbook.lu -> $(SEC_CONFIG) ;
#/root/.addressbook -> $(SEC_CONFIG) ;
#/root/.Xresources -> $(SEC_CONFIG) ;
#/root/.Xauthority -> $(SEC_CONFIG) -i ; # Changes Inode number on login
/root/.ICEauthority -> $(SEC_CONFIG) ;
}
#
# Critical devices
#
(
rulename = "Devices & Kernel information",
severity = $(SIG_HI),
)
{
#/dev -> $(Device) ;
#/proc -> $(Device) ;
}
tripwire 報告
tripwire-check 命令檢查 twpol.txt 文件並基於此文件生成 tripwire 報告如下。如果 twpol.txt 中有任何錯誤,tripwire 不會生成報告。
文本形式報告
root@VMdebian:/home/labadmin# tripwire --check
Parsing policy file: /etc/tripwire/tw.pol
*** Processing Unix File System ***
Performing integrity check...
Wrote report file: /var/lib/tripwire/report/VMdebian-20151024-122322.twr
Open Source tripwire(R) 2.4.2.2 Integrity Check Report
Report generated by: root
Report created on: Sat Oct 24 12:23:22 2015
Database last updated on: Never
Report Summary:
=========================================================
Host name: VMdebian
Host IP address: 127.0.1.1
Host ID: None
Policy file used: /etc/tripwire/tw.pol
Configuration file used: /etc/tripwire/tw.cfg
Database file used: /var/lib/tripwire/VMdebian.twd
Command line used: tripwire --check
=========================================================
Rule Summary:
=========================================================
----------------------------------------------------------------------------
Section: Unix File System
----------------------------------------------------------------------------
Rule Name Severity Level Added Removed Modified
--------- -------------- ----- ------- -----
Other binaries 66 0 0 0
tripwire Binaries 100 0 0 0
Other libraries 66 0 0 0
Root file-system executables 100 0 0 0
tripwire Data Files 100 0 0 0
System boot changes 100 0 0 0
(/var/log)
Root file-system libraries 100 0 0 0
(/lib)
Critical system boot files 100 0 0 0
Other configuration files 66 0 0 0
(/etc)
Boot Scripts 100 0 0 0
Security Control 66 0 0 0
Root config files 100 0 0 0
Invariant Directories 66 0 0 0
Total objects scanned: 25943
Total violations found: 0
=========================Object Summary:================================
----------------------------------------------------------------------------
# Section: Unix File System
----------------------------------------------------------------------------
No violations.
===========================Error Report:=====================================
No Errors
----------------------------------------------------------------------------
*** End of report ***
Open Source tripwire 2.4 Portions copyright 2000 tripwire, Inc. tripwire is a registered
trademark of tripwire, Inc. This software comes with ABSOLUTELY NO WARRANTY;
for details use --version. This is free software which may be redistributed
or modified only under certain conditions; see COPYING for details.
All rights reserved.
Integrity check complete.
總結
本篇中,我們學習安裝配置開源入侵檢測軟體 tripwire。首先生成基礎資料庫並通過比較檢測出任何改動(文件/文件夾)。然而,tripwire 並不是實時監測的 IDS。
via: http://linoxide.com/security/configure-tripwire-ids-debian/
本文轉載來自 Linux 中國: https://github.com/Linux-CN/archive