Contents
Suricata インストール
1.事前準備
①EPEL リポジトリをシステム上で有効化する
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# dnf -y install epel-release |
②システムのアップデート
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# dnf update -y |
2.Suricata のインストールと設定
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# dnf install suricata |
バージョンの確認
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# suricata -V This is Suricata version 6.0.9 RELEASE |
②Suricataがネットワークパケットを検査するインターフェースとIPアドレスを決定
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# ip --brief add lo UNKNOWN 127.0.0.1/8 ::1/128 ens160 UP 192.168.11.83/24 fe80::20c:29ff:fe70:b911/64 |
③設定ファイルを編集
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# vi /etc/suricata/suricata.yaml # 18行目 : varsセクションで、ネットワークを定義する HOME_NET: "[192.168.11.0/24]" EXTRNAL_NET: "!$HOME_NET" # 589行目 : af-packetセクションのインターフェース名を設定 af-packet: - interface: ens160 |
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# vi /etc/sysconfig/suricata # 8行目 :インターフェイスを指定 # Add options to be passed to the daemon OPTIONS="-i ens160 --user suricata " |
④Suricataのルール更新
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# suricata-update ------ 24/2/2023 -- 10:12:31 - <Info> -- Done. |
⑤Suricataの起動
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# systemctl enable --now suricata Created symlink /etc/systemd/system/multiuser.target.wants/suricata.service → /usr/lib/systemd/system/suricata.service. |
⑥Suricataの起動確認
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# systemctl status suricata ● suricata.service - Suricata Intrusion Detection Service Loaded: loaded (/usr/lib/systemd/system/suricata.service; enabled; preset:> Active: active (running) since Fri 2023-02-24 10:14:09 JST; 1min 37s ago Docs: man:suricata(1) Process: 6032 ExecStartPre=/bin/rm -f /var/run/suricata.pid (code=exited, s> Main PID: 6033 (Suricata-Main) Tasks: 8 (limit: 48774) Memory: 452.2M CPU: 19.816s CGroup: /system.slice/suricata.service mq6033 /sbin/suricata -c /etc/suricata/suricata.yaml --pidfile /va> Feb 24 10:14:09 Lepard systemd[1]: Starting Suricata Intrusion Detection Servic> Feb 24 10:14:09 Lepard systemd[1]: Started Suricata Intrusion Detection Service. Feb 24 10:14:09 Lepard suricata[6033]: 24/2/2023 -- 10:14:09 - <Notice> - This > Feb 24 10:14:09 Lepard suricata[6033]: 24/2/2023 -- 10:14:09 - <Warning> - [ERR> Feb 24 10:14:09 Lepard suricata[6033]: 24/2/2023 -- 10:14:09 - <Warning> - [ERR> Feb 24 10:14:09 Lepard suricata[6033]: 24/2/2023 -- 10:14:09 - <Warning> - [ERR> Feb 24 10:14:29 Lepard suricata[6033]: 24/2/2023 -- 10:14:29 - <Notice> - all 2 |
ログを確認
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# tail /var/log/suricata/suricata.log 24/2/2023 -- 10:14:09 - <Info> - stats output device (regular) initialized: stats.log 24/2/2023 -- 10:14:09 - <Info> - Running in live mode, activating unix socket 24/2/2023 -- 10:14:20 - <Info> - 1 rule files processed. 33257 rules successfully loaded, 0 rules failed 24/2/2023 -- 10:14:20 - <Info> - Threshold config parsed: 0 rule(s) found 24/2/2023 -- 10:14:21 - <Info> - 33260 signatures processed. 1189 are IP-only rules, 5209 are inspecting packet payload, 26659 inspect application layer, 108 are decoder event only 24/2/2023 -- 10:14:29 - <Info> - Going to use 2 thread(s) 24/2/2023 -- 10:14:29 - <Info> - Running in live mode, activating unix socket 24/2/2023 -- 10:14:29 - <Info> - Using unix socket file '/var/run/suricata/suricata-command.socket' 24/2/2023 -- 10:14:29 - <Notice> - all 2 packet processing threads, 4 management threads initialized, engine started. 24/2/2023 -- 10:14:29 - <Info> - All AFP capture threads are running. |
統計情報を確認するには、stats.log ファイルを確認します(デフォルトで8秒ごとに更新)
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# tail -f /var/log/suricata/stats.log |
より高度な出力であるEVE JSONは、以下のコマンドで生成することができる
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# tail -f /var/log/suricata/eve.json |
3.Suricata のテスト
①curl ユーティリティで ping テストを実行
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# curl http://testmynids.org/uid/index.html uid=0(root) gid=0(root) groups=0(root) |
②ログに記録されたかどうかを調べるため、アラートログを確認
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# cat /var/log/suricata/fast.log |
4.Suricata Rulesの設定
①Suricataにパッケージされているルールセットの表示
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# ls -al /var/lib/suricata/rules/ drwxr-s--- 2 root suricata 57 Feb 24 10:12 . drwxrws--- 4 suricata suricata 33 Feb 24 10:12 .. -rw-r--r-- 1 root suricata 3228 Feb 24 10:12 classification.config -rw-r--r-- 1 root suricata 23546596 Feb 24 10:12 suricata.rules |
②ルールセットを提供するソースのインデックス一覧
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# suricata-update list-sources Name: et/open Vendor: Proofpoint Summary: Emerging Threats Open Ruleset License: MIT Name: et/pro Vendor: Proofpoint Summary: Emerging Threats Pro Ruleset License: Commercial Replaces: et/open Parameters: secret-code Subscription: https://www.proofpoint.com/us/threat-insight/et-pro-ruleset Name: oisf/trafficid Vendor: OISF Summary: Suricata Traffic ID ruleset License: MIT Name: scwx/enhanced Vendor: Secureworks Summary: Secureworks suricata-enhanced ruleset License: Commercial Parameters: secret-code Subscription: https://www.secureworks.com/contact/ (Please reference CTU Countermeasures) Name: scwx/malware Vendor: Secureworks Summary: Secureworks suricata-malware ruleset License: Commercial Parameters: secret-code Subscription: https://www.secureworks.com/contact/ (Please reference CTU Countermeasures) Name: scwx/security Vendor: Secureworks Summary: Secureworks suricata-security ruleset License: Commercial Parameters: secret-code Subscription: https://www.secureworks.com/contact/ (Please reference CTU Countermeasures) Name: sslbl/ssl-fp-blacklist Vendor: Abuse.ch Summary: Abuse.ch SSL Blacklist License: Non-Commercial Name: sslbl/ja3-fingerprints Vendor: Abuse.ch Summary: Abuse.ch Suricata JA3 Fingerprint Ruleset License: Non-Commercial Name: etnetera/aggressive Vendor: Etnetera a.s. Summary: Etnetera aggressive IP blacklist License: MIT Name: tgreen/hunting Vendor: tgreen Summary: Threat hunting rules License: GPLv3 Name: malsilo/win-malware Vendor: malsilo Summary: Commodity malware rules License: MIT Name: stamus/lateral Vendor: Stamus Networks Summary: Lateral movement rules License: GPL-3.0-only |
③ソースを有効にする(例として et/openを有効にする場合)
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# suricata-update enable-source et/open 24/2/2023 -- 10:25:44 - <Info> -- Using data-directory /var/lib/suricata. 24/2/2023 -- 10:25:44 - <Info> -- Using Suricata configuration /etc/suricata/suricata.yaml 24/2/2023 -- 10:25:44 - <Info> -- Using /usr/share/suricata/rules for Suricata provided rules. 24/2/2023 -- 10:25:44 - <Info> -- Found Suricata version 6.0.9 at /usr/sbin/suricata. 24/2/2023 -- 10:25:44 - <Info> -- Creating directory /var/lib/suricata/update/sources 24/2/2023 -- 10:25:44 - <Info> -- Source et/open enabled |
アップデートを実行
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# suricata-update |
Suricata service再起動
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# systemctl restart suricata |
5.Suricata Custom Rulesの作成
①カスタマールールを含むファイルを作成
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# vi /etc/suricata/rules/local.rules 下記内容を記載 alert icmp any any -> $HOME_NET any (msg:"ICMP Ping"; sid:1; rev:1;) |
②設定ファイルを編集(新しいルールのパスを定義)
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# vi /etc/suricata/suricata.yaml # 1924行目あたりに追記 default-rule-path: /var/lib/suricata/rules rule-files: - suricata.rules - /etc/suricata/rules/local.rules |
③設定ファイルのテスト
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# suricata -T -c /etc/suricata/suricata.yaml -v --------- 24/2/2023 -- 10:31:55 - <Info> - fast output device (regular) initialized: fast.log 24/2/2023 -- 10:31:55 - <Info> - eve-log output device (regular) initialized: eve.json 24/2/2023 -- 10:31:55 - <Info> - stats output device (regular) initialized: stats.log 24/2/2023 -- 10:32:06 - <Info> - 2 rule files processed. 33258 rules successfully loaded, 0 rules failed 24/2/2023 -- 10:32:06 - <Info> - Threshold config parsed: 0 rule(s) found 24/2/2023 -- 10:32:06 - <Info> - 33261 signatures processed. 1190 are IP-only rules, 5209 are inspecting packet payload, 26659 inspect application layer, 108 are decoder event only 24/2/2023 -- 10:32:14 - <Notice> - Configuration provided was successfully loaded. Exiting. 24/2/2023 -- 10:32:14 - <Info> - cleaning up signature grouping structure... complete |
suricat service再起動
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# systemctl restart suricata |
④Custom Rulesの適用テスト
同一ローカルネットワーク上の別のデバイスでpingを実行し、ログに記録されたかどうかを確認する
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# cat /var/log/suricata/fast.log |
JSON形式のログを取得するには、システムにjqをインストールする
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# dnf install jq |
下記コマンドを実行し、同一ローカルネットワーク上の別のデバイスでpingを実行する
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# tail -f /var/log/suricata/eve.json | jq 'select(.event_type=="alert")' pingを実行するとコンソールに下記のように表示される { "timestamp": "2023-02-24T10:37:24.991420+0900", "flow_id": 184159957091405, "in_iface": "ens160", "event_type": "alert", "src_ip": "192.168.11.83", "src_port": 587, "dest_ip": "46.148.40.168", "dest_port": 48394, "proto": "TCP", "metadata": { "flowints": { "applayer.anomaly.count": 1 } }, "alert": { "action": "allowed", "gid": 1, "signature_id": 2260002, "rev": 1, "signature": "SURICATA Applayer Detect protocol only one direction", "category": "Generic Protocol Command Decode", "severity": 3 }, "smtp": { "helo": "localhost" }, "app_proto": "smtp", "app_proto_tc": "failed", "flow": { "pkts_toserver": 4, "pkts_toclient": 3, "bytes_toserver": 288, "bytes_toclient": 242, "start": "2023-02-24T10:37:23.721997+0900" } } |
Tripwire インストール
1.ダウンロード、インストール
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# cd /usr/local/src # wget https://rpmfind.net/linux/epel/9/Everything/x86_64/Packages/t/tripwire-2.4.3.7-13.el9.x86_64.rpm # rpm -Uvh tripwire-2.4.3.7-13.el9.x86_64.rpm |
2.パスフレーズ設定
サイトパスフレーズとローカルパスフレーズを設定する
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# tripwire-setup-keyfiles ---------------------------------------------- The Tripwire site and local passphrases are used to sign a variety of files, such as the configuration, policy, and database files. Passphrases should be at least 8 characters in length and contain both letters and numbers. See the Tripwire manual for more information. ---------------------------------------------- Creating key files... (When selecting a passphrase, keep in mind that good passphrases typically have upper and lower case letters, digits and punctuation marks, and are at least 8 characters in length.) Enter the site keyfile passphrase: ←任意の「サイトパスフレーズ」を入力 Verify the site keyfile passphrase: ←再度「サイトパスフレーズ」を入力 Generating key (this may take several minutes)...Key generation complete. (When selecting a passphrase, keep in mind that good passphrases typically have upper and lower case letters, digits and punctuation marks, and are at least 8 characters in length.) Enter the local keyfile passphrase: ←任意の「ローカルパスフレーズ」を入力 Verify the local keyfile passphrase: ←再度「ローカルパスフレーズ」を入力 Generating key (this may take several minutes)...Key generation complete. ---------------------------------------------- Signing configuration file... Please enter your site passphrase: 「サイトパスフレーズ」を入力 Wrote configuration file: /etc/tripwire/tw.cfg A clear-text version of the Tripwire configuration file: /etc/tripwire/twcfg.txt has been preserved for your inspection. It is recommended that you move this file to a secure location and/or encrypt it in place (using a tool such as GPG, for example) after you have examined it. ---------------------------------------------- Signing policy file... Please enter your site passphrase: 「サイトパスフレーズ」を入力 Wrote policy file: /etc/tripwire/tw.pol A clear-text version of the Tripwire policy file: /etc/tripwire/twpol.txt has been preserved for your inspection. This implements a minimal policy, intended only to test essential Tripwire functionality. You should edit the policy file to describe your system, and then use twadmin to generate a new signed copy of the Tripwire policy. Once you have a satisfactory Tripwire policy file, you should move the clear-text version to a secure location and/or encrypt it in place (using a tool such as GPG, for example). Now run "tripwire --init" to enter Database Initialization Mode. This reads the policy file, generates a database based on its contents, and then cryptographically signs the resulting database. Options can be entered on the command line to specify which policy, configuration, and key files are used to create the database. The filename for the database can be specified as well. If no options are specified, the default values from the current configuration file are used. |
3.Tripwire の設定
①設定ファイル編集
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# vi /etc/tripwire/twcfg.txt ●9 行目あたり 行頭に「#」を追加し、その下の行に「LOOSEDIRECTORYCHECKING =true」を追加します。 ●12 行目あたり 行頭に「#」を追加し、その下の行に「REPORTLEVEL =4」を追加します。 レベル4 にすることで「0 」～「4 」までの5 段階中、最も詳細なレポートが表示されます。 #REPORTLEVEL =3 REPORTLEVEL =4 |
②Tripwire 設定ファイル(暗号署名版)を作成
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# twadmin -m F -c /etc/tripwire/tw.cfg -S /etc/tripwire/site.key /etc/tripwire/twcfg.txt Please enter your site passphrase: ←サイトパスフレーズを入力 Wrote configuration file: /etc/tripwire/tw.cfg |
③Tripwire 設定ファイル(テキスト版)削除
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# rm -f /etc/tripwire/twcfg.txt |
④ポリシーファイル設定
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# cd /etc/tripwire/ # vi twpolmake.pl |
twpolmake.plの内容
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#!/usr/bin/perl # Tripwire Policy File customize tool # $POLFILE=$ARGV[0]; open(POL,"$POLFILE") or die "open error: $POLFILE" ; my($myhost,$thost) ; my($sharp,$tpath,$cond) ; my($INRULE) = 0 ; while (<POL>) { chomp; if (($thost) = /^HOSTNAME\s*=\s*(.*)\s*;/) { $myhost = `hostname` ; chomp($myhost) ; if ($thost ne $myhost) { $_="HOSTNAME=\"$myhost\";" ; } } elsif ( /^{/ ) { $INRULE=1 ; } elsif ( /^}/ ) { $INRULE=0 ; } elsif ($INRULE == 1 and ($sharp,$tpath,$cond) = /^(\s*\#?\s*)(\/\S+)\b(\s+->\s+.+)$/) { $ret = ($sharp =~ s/\#//g) ; if ($tpath eq '/sbin/e2fsadm' ) { $cond =~ s/;\s+(tune2fs.*)$/; \#$1/ ; } if (! -s $tpath) { $_ = "$sharp#$tpath$cond" if ($ret == 0) ; } else { $_ = "$sharp$tpath$cond" ; } } print "$_\n" ; } close(POL) ; |
⑤ポリシーファイル最適化
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# perl /etc/tripwire/twpolmake.pl /etc/tripwire/twpol.txt > /etc/tripwire/twpol.txt.new |
⑥最適化済ポリシーファイルを元に、ポリシーファイル(暗号署名版)作成
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# twadmin -m P -c /etc/tripwire/tw.cfg -p /etc/tripwire/tw.pol -S /etc/tripwire/site.key /etc/tripwire/twpol.txt.new Please enter your site passphrase: ←サイトパスフレーズを入力 Wrote policy file: /etc/tripwire/tw.pol |
⑦データベースを作成、動作確認
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# tripwire -m i -s -c /etc/tripwire/tw.cfg Please enter your local passphrase: ←ローカルパスフレーズを入力 |
⑧テスト用ファイルを作成し動作確認
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テスト用ファイルを作成 # echo test > /root/test.txt Tripwire の動作確認 # tripwire -m c -s -c /etc/tripwire/tw.cfg 下記のように表示されればOK |
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Open Source Tripwire(R) 2.4.3.7 Integrity Check Report Report generated by: root Report created on: Fri 24 Feb 2023 10:58:41 AM JST Database last updated on: Never =============================================================================== Report Summary: =============================================================================== Host name: Lepard Host IP address: 192.168.11.83 Host ID: None Policy file used: /etc/tripwire/tw.pol Configuration file used: /etc/tripwire/tw.cfg Database file used: /var/lib/tripwire/Lepard.twd Command line used: tripwire -m c -s -c /etc/tripwire/tw.cfg =============================================================================== Rule Summary: =============================================================================== ------------------------------------------------------------------------------- Section: Unix File System ------------------------------------------------------------------------------- Rule Name Severity Level Added Removed Modified --------- -------------- ----- ------- -------- User binaries 66 0 0 0 Tripwire Binaries 100 0 0 0 Libraries 66 0 0 0 Operating System Utilities 100 0 0 0 File System and Disk Administraton Programs 100 0 0 0 Kernel Administration Programs 100 0 0 0 Networking Programs 100 0 0 0 System Administration Programs 100 0 0 0 Hardware and Device Control Programs 100 0 0 0 System Information Programs 100 0 0 0 (/sbin/runlevel) Application Information Programs 100 0 0 0 (/sbin/rtmon) Critical Utility Sym-Links 100 0 0 0 Shell Binaries 100 0 0 0 Critical system boot files 100 0 0 0 * Tripwire Data Files 100 1 0 0 System boot changes 100 0 0 0 OS executables and libraries 100 0 0 0 Security Control 100 0 0 0 Login Scripts 100 0 0 0 Critical configuration files 100 0 0 0 * Root config files 100 1 0 0 Invariant Directories 66 0 0 0 Temporary directories 33 0 0 0 Critical devices 100 0 0 0 (/proc/kcore) Total objects scanned: 39686 Total violations found: 2 =============================================================================== Object Summary: =============================================================================== ------------------------------------------------------------------------------- # Section: Unix File System ------------------------------------------------------------------------------- ------------------------------------------------------------------------------- Rule Name: Tripwire Data Files (/var/lib/tripwire) Severity Level: 100 ------------------------------------------------------------------------------- Added: "/var/lib/tripwire/Lepard.twd" ------------------------------------------------------------------------------- Rule Name: Root config files (/root) Severity Level: 100 ------------------------------------------------------------------------------- Added: "/root/test.txt" =============================================================================== Error Report: =============================================================================== No Errors ------------------------------------------------------------------------------- *** End of report *** Open Source Tripwire 2.4 Portions copyright 2000-2018 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. |
テスト用ファイルを削除
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# rm -f /root/test.txt |
⑨Tripwire 定期実行スクリプト
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# cd /var/www/system # vi tripwire.sh |
tripwire.shの内容
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#!/bin/bash PATH=/usr/sbin:/usr/bin:/bin:/usr/local/tripwire/sbin # パスフレーズ設定 LOCALPASS=xxxxxxx ←ローカルパスフレーズ SITEPASS=xxxxxxx ←サイトパスフレーズ cd /etc/tripwire # Tripwireチェック実行 tripwire -m c -s -c tw.cfg|mail -s "Tripwire(R) Integrity Check Report in `hostname`" root # ポリシーファイル最新化 twadmin -m p -c tw.cfg -p tw.pol -S site.key > twpol.txt perl twpolmake.pl twpol.txt > twpol.txt.new twadmin -m P -c tw.cfg -p tw.pol -S site.key -Q $SITEPASS twpol.txt.new > /dev/null rm -f twpol.txt* *.bak # データベース最新化 rm -f /usr/local/tripwire/lib/tripwire/*.twd* tripwire -m i -s -c tw.cfg -P $LOCALPASS |
⑩Tripwire 自動実行スクリプト実行設定
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# chmod 700 tripwire.sh |
cron に追加
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# crontab -e 0 3 * * * /var/www/system/tripwire.sh |
参考: メールで結果報告用スクリプト
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#!/bin/bash PATH=/usr/sbin:/usr/bin:/bin:/usr/local/tripwire/sbin # パスフレーズ設定 LOCALPASS=xxxxx # ローカルキーパスフレーズ SITEPASS=xxxxx # サイトキーパスフレーズ #通知先メールアドレス指定 MAIL="<your mailaddress> " cd /etc/tripwire # Tripwireチェック実行 tripwire -m c -s -c tw.cfg|mail -s "Tripwire(R) Integrity Check Report in `hostname`" $MAIL # ポリシーファイル最新化 twadmin -m p -c tw.cfg -p tw.pol -S site.key > twpol.txt perl twpolmake.pl twpol.txt > twpol.txt.new twadmin -m P -c tw.cfg -p tw.pol -S site.key -Q $SITEPASS twpol.txt.new > /dev/null rm -f twpol.txt* *.bak # データベース最新化 rm -f /usr/local/tripwire/lib/tripwire/*.twd* tripwire -m i -s -c tw.cfg -P $LOCALPASS |
下記コマンドを実行し、指定したメールアドレスにtripwire実行結果が通知されることを確認
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# /var/www/system/tripwire.sh |
Chkrootkit インストール
①chkrootkit をダウンロード、インストール
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# cd /usr/local/src # wget https://launchpad.net/chkrootkit/main/0.55/+download/chkrootkit-0.55.tar.gz # tar xvf chkrootkit-0.55.tar.gz |
➁/root/bin ディレクトリを作成し、そのディレクトリにchkrootkit コマンドを移動
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# mkdir -p /root/bin # mv chkrootkit-0.55/chkrootkit /root/bin |
➂chkrootkit を確認
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# chkrootkit | grep INFECTED 何も表示されなければ問題ありません |
Checking `chsh'… INFECTED
上記の表示が出る場合は誤検知のため問題ありません
④chkrootkit 定期実行スクリプトの作成と権限変更
chkrootkit実行スクリプトを毎日自動実行されるディレクトリへ作成
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# vi /etc/cron.daily/chkrootkit |
定期実行スクリプトの内容
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#!/bin/bash PATH=/usr/bin:/bin:/root/bin LOG=/tmp/$(basename ${0}) # chkrootkit実行 chkrootkit > $LOG 2>&1 # ログ出力 cat $LOG | logger -t $(basename ${0}) # SMTPSのbindshell誤検知対応 if [ ! -z "$(grep 465 $LOG)" ] && \ [ -z $(/usr/sbin/lsof -i:465|grep bindshell) ]; then sed -i '/465/d' $LOG fi # upstartパッケージ更新時のSuckit誤検知対応 if [ ! -z "$(grep Suckit $LOG)" ] && \ [ -z "$(rpm -V `rpm -qf /sbin/init`)" ]; then sed -i '/Suckit/d' $LOG fi # rootkit検知時のみroot宛メール送信 [ ! -z "$(grep INFECTED $LOG)" ] && \ grep INFECTED $LOG | mail -s "chkrootkit report in `hostname`" root |
chkrootkit実行スクリプトへ実行権限付加
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# chmod 700 /etc/cron.daily/chkrootkit |
⑥chkrootkit が使用するコマンドをバックアップ
chkrootkit が使用するコマンドが改ざんされた場合、rootkit を検出できなくなるので、
これらのコマンドをバックアップしておきます。
必要な場合は、バックアップしたコマンドを使用してchkrootkit を実行します
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# cd /root # mkdir /root/chkrootkit_cmd # cp `which --skip-alias awk cut echo egrep find head id ls netstat ps strings sed ssh uname` chkrootkit_cmd/ # ls -l /root/chkrootkit_cmd/ total 2616 -rwxr-xr-x 1 root root 714976 Feb 24 11:19 awk -rwxr-xr-x 1 root root 48760 Feb 24 11:19 cut -rwxr-xr-x 1 root root 36136 Feb 24 11:19 echo -rwxr-xr-x 1 root root 32 Feb 24 11:19 egrep -rwxr-xr-x 1 root root 292760 Feb 24 11:19 find -rwxr-xr-x 1 root root 44656 Feb 24 11:19 head -rwxr-xr-x 1 root root 40472 Feb 24 11:19 id -rwxr-xr-x 1 root root 140760 Feb 24 11:19 ls -rwxr-xr-x 1 root root 161600 Feb 24 11:19 netstat -rwxr-xr-x 1 root root 144432 Feb 24 11:19 ps -rwxr-xr-x 1 root root 116728 Feb 24 11:19 sed -rwxr-xr-x 1 root root 851224 Feb 24 11:19 ssh -rwxr-xr-x 1 root root 32504 Feb 24 11:19 strings -rwxr-xr-x 1 root root 32232 Feb 24 11:19 uname |
⑦コピーしたコマンドにchkrootkit を実行
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# chkrootkit -p /root/chkrootkit_cmd | grep INFECTED |
⑧バックアップしたコマンドを圧縮
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# tar zcvf chkrootkit_cmd.tar.gz chkrootkit_cmd |
⑨Windows にchkrootkit_cmd.tar.gz ファイルをダウンロードして退避