■「openssl s_client」でSSLサーバのテストを行ってみる。 $ lsb_release -d Description: Debian GNU/Linux 8.4 (jessie) $ openssl version OpenSSL 1.0.1k 8 Jan 2015 ■公開サイトからのSSLテストを行う場合 「普通は公開前にテストするよね！」という人はローカル方式を探すかと思います。 SSL Server Test https://www.ssllabs.com/ssltest/ ■ローカルサイトからのSSLテスト 以下よりダウンロードして実行権を付与して実行 SSLTest http://www.thegreycorner.com/p/ssltest.html $ chmod +x ssltest.pl $ perl -v | awk '/^This/' This is perl 5, version 20, subversion 2 (v5.20.2) built for x86_64-linux-gnu-thread-multi ■下記はデフォルトではSSLv3+RC4がデフォルトで使えていた頃の話。 有効にしようと思えば可能だが、脆弱になるのでお勧めしない。 openssl ciphersのDEAFULTとapache2のssl.conf http://labunix.hateblo.jp/entry/20140211/1392048666 FREAK Attack(CVE2015-0204)について http://labunix.hateblo.jp/entry/20150305/1425487029 $ sudo openssl ciphers -V 'HIGH:MEDIUM:!aNULL:!MD5' | awk '/RC4|SSLv2/' 0xC0,0x11 - ECDHE-RSA-RC4-SHA SSLv3 Kx=ECDH Au=RSA Enc=RC4(128) Mac=SHA1 0xC0,0x07 - ECDHE-ECDSA-RC4-SHA SSLv3 Kx=ECDH Au=ECDSA Enc=RC4(128) Mac=SHA1 0xC0,0x0C - ECDH-RSA-RC4-SHA SSLv3 Kx=ECDH/RSA Au=ECDH Enc=RC4(128) Mac=SHA1 0xC0,0x02 - ECDH-ECDSA-RC4-SHA SSLv3 Kx=ECDH/ECDSA Au=ECDH Enc=RC4(128) Mac=SHA1 0x00,0x05 - RC4-SHA SSLv3 Kx=RSA Au=RSA Enc=RC4(128) Mac=SHA1 0x00,0x8A - PSK-RC4-SHA SSLv3 Kx=PSK Au=PSK Enc=RC4(128) Mac=SHA1 ■対象のWebサーバのバージョンと使用可能な暗号化方式(SSLCipherSuite)と、暗号通信方式(SSLProtocol)の確認。 現在のWebサーバでは、デフォルトでRC4もSSLv2も使用しないし、SSLv3も除外されている。 HIGHは128bit以上、aNULLは認証しないものなので、検査対象は28の暗号化方式のみ。 また、TLSv1.0もTLSv1.1も無い。 $ dpkg -l apache2 | awk '/^ii/{print $2,$3}' apache2 2.4.10-10+deb8u4 $ awk '/^\tSSL[CP][ri]/' /etc/apache2/mods-available/ssl.conf SSLCipherSuite HIGH:!aNULL SSLProtocol all -SSLv3 $ sudo openssl ciphers -V 'HIGH:!aNULL' | awk '/RC4|SSLv2/' $ sudo openssl ciphers -V 'HIGH:!aNULL' | awk '!/SSLv3/{sum+=1;gsub(" *",",",$0);print}END{print sum}' ,0xC0,0x30,-,ECDHE-RSA-AES256-GCM-SHA384,TLSv1.2,Kx=ECDH,Au=RSA,Enc=AESGCM(256),Mac=AEAD ,0xC0,0x2C,-,ECDHE-ECDSA-AES256-GCM-SHA384,TLSv1.2,Kx=ECDH,Au=ECDSA,Enc=AESGCM(256),Mac=AEAD ,0xC0,0x28,-,ECDHE-RSA-AES256-SHA384,TLSv1.2,Kx=ECDH,Au=RSA,Enc=AES(256),Mac=SHA384 ,0xC0,0x24,-,ECDHE-ECDSA-AES256-SHA384,TLSv1.2,Kx=ECDH,Au=ECDSA,Enc=AES(256),Mac=SHA384 ,0x00,0xA3,-,DHE-DSS-AES256-GCM-SHA384,TLSv1.2,Kx=DH,Au=DSS,Enc=AESGCM(256),Mac=AEAD ,0x00,0x9F,-,DHE-RSA-AES256-GCM-SHA384,TLSv1.2,Kx=DH,Au=RSA,Enc=AESGCM(256),Mac=AEAD ,0x00,0x6B,-,DHE-RSA-AES256-SHA256,TLSv1.2,Kx=DH,Au=RSA,Enc=AES(256),Mac=SHA256 ,0x00,0x6A,-,DHE-DSS-AES256-SHA256,TLSv1.2,Kx=DH,Au=DSS,Enc=AES(256),Mac=SHA256 ,0xC0,0x32,-,ECDH-RSA-AES256-GCM-SHA384,TLSv1.2,Kx=ECDH/RSA,Au=ECDH,Enc=AESGCM(256),Mac=AEAD ,0xC0,0x2E,-,ECDH-ECDSA-AES256-GCM-SHA384,TLSv1.2,Kx=ECDH/ECDSA,Au=ECDH,Enc=AESGCM(256),Mac=AEAD ,0xC0,0x2A,-,ECDH-RSA-AES256-SHA384,TLSv1.2,Kx=ECDH/RSA,Au=ECDH,Enc=AES(256),Mac=SHA384 ,0xC0,0x26,-,ECDH-ECDSA-AES256-SHA384,TLSv1.2,Kx=ECDH/ECDSA,Au=ECDH,Enc=AES(256),Mac=SHA384 ,0x00,0x9D,-,AES256-GCM-SHA384,TLSv1.2,Kx=RSA,Au=RSA,Enc=AESGCM(256),Mac=AEAD ,0x00,0x3D,-,AES256-SHA256,TLSv1.2,Kx=RSA,Au=RSA,Enc=AES(256),Mac=SHA256 ,0xC0,0x2F,-,ECDHE-RSA-AES128-GCM-SHA256,TLSv1.2,Kx=ECDH,Au=RSA,Enc=AESGCM(128),Mac=AEAD ,0xC0,0x2B,-,ECDHE-ECDSA-AES128-GCM-SHA256,TLSv1.2,Kx=ECDH,Au=ECDSA,Enc=AESGCM(128),Mac=AEAD ,0xC0,0x27,-,ECDHE-RSA-AES128-SHA256,TLSv1.2,Kx=ECDH,Au=RSA,Enc=AES(128),Mac=SHA256 ,0xC0,0x23,-,ECDHE-ECDSA-AES128-SHA256,TLSv1.2,Kx=ECDH,Au=ECDSA,Enc=AES(128),Mac=SHA256 ,0x00,0xA2,-,DHE-DSS-AES128-GCM-SHA256,TLSv1.2,Kx=DH,Au=DSS,Enc=AESGCM(128),Mac=AEAD ,0x00,0x9E,-,DHE-RSA-AES128-GCM-SHA256,TLSv1.2,Kx=DH,Au=RSA,Enc=AESGCM(128),Mac=AEAD ,0x00,0x67,-,DHE-RSA-AES128-SHA256,TLSv1.2,Kx=DH,Au=RSA,Enc=AES(128),Mac=SHA256 ,0x00,0x40,-,DHE-DSS-AES128-SHA256,TLSv1.2,Kx=DH,Au=DSS,Enc=AES(128),Mac=SHA256 ,0xC0,0x31,-,ECDH-RSA-AES128-GCM-SHA256,TLSv1.2,Kx=ECDH/RSA,Au=ECDH,Enc=AESGCM(128),Mac=AEAD ,0xC0,0x2D,-,ECDH-ECDSA-AES128-GCM-SHA256,TLSv1.2,Kx=ECDH/ECDSA,Au=ECDH,Enc=AESGCM(128),Mac=AEAD ,0xC0,0x29,-,ECDH-RSA-AES128-SHA256,TLSv1.2,Kx=ECDH/RSA,Au=ECDH,Enc=AES(128),Mac=SHA256 ,0xC0,0x25,-,ECDH-ECDSA-AES128-SHA256,TLSv1.2,Kx=ECDH/ECDSA,Au=ECDH,Enc=AES(128),Mac=SHA256 ,0x00,0x9C,-,AES128-GCM-SHA256,TLSv1.2,Kx=RSA,Au=RSA,Enc=AESGCM(128),Mac=AEAD ,0x00,0x3C,-,AES128-SHA256,TLSv1.2,Kx=RSA,Au=RSA,Enc=AES(128),Mac=SHA256 28 ■私の環境ではSquidの内部用ブロックページとしか使っていないのですが。。。 ところでデフォルトから従来の方法で「a2enmod ssl」しただけでは、 「SSL routines:SSL23_GET_SERVER_HELLO:unknown protocol」となる。 $ w3m -dump http://172.31.31.254:443 Deny Pages! black $ w3m -dump https://172.31.31.254:443 SSL error: error:140770FC:SSL routines:SSL23_GET_SERVER_HELLO:unknown protocol w3m: Can't load https://172.31.31.254:443. ■上記は「a2ensite」を実行していないから。 $ head -4 /etc/apache2/ports.conf # If you just change the port or add more ports here, you will likely also # have to change the VirtualHost statement in # /etc/apache2/sites-enabled/000-default.conf $ sudo a2ensite default-ssl.conf Enabling site default-ssl. To activate the new configuration, you need to run: service apache2 reload $ sudo systemctl reload apache2.service ■初回は少し詳しく出力してみる。 証明書は組み込みの自己署名証明書なので、当然のログが出る。 $ wget -O /dev/null --debug --no-check-certificate --no-proxy https://172.31.31.254/ Setting --check-certificate (checkcertificate) to 0 Setting --proxy (useproxy) to 0 DEBUG output created by Wget 1.16 on linux-gnu. URI encoding = `UTF-8' --2016-05-31 22:50:01-- https://172.31.31.254/ Certificates loaded: 174 172.31.31.254:443 に接続しています... 接続しました。 Created socket 5. Releasing 0x00000000024f0a10 (new refcount 0). Deleting unused 0x00000000024f0a10. 警告: `172.31.31.254' の証明書は信用されません。 警告: `172.31.31.254' の証明書の発行者が不明です。 証明書の所有者の名前とホスト名 `172.31.31.254' が一致しません ---request begin--- GET / HTTP/1.1 User-Agent: Wget/1.16 (linux-gnu) Accept: */* Host: 172.31.31.254 Connection: Keep-Alive ---request end--- HTTP による接続要求を送信しました、応答を待っています... ---response begin--- HTTP/1.1 200 OK Date: Tue, 31 May 2016 13:50:01 GMT Server: Apache/2.4.10 (Debian) Last-Modified: Sun, 11 Oct 2015 03:40:39 GMT ETag: "36-521cbf9f6fa59" Accept-Ranges: bytes Content-Length: 54 Keep-Alive: timeout=5, max=100 Connection: Keep-Alive Content-Type: text/html ---response end--- 200 OK Registered socket 5 for persistent reuse. 長さ: 54 [text/html] `/dev/null' に保存中 /dev/null 100%[=============================================================>] 54 --.-KB/s 時間 0s 2016-05-31 22:50:01 (3.35 MB/s) - `/dev/null' へ保存完了 [54/54] ■上記を元にopensslコマンドでテストしてみる。 ここから先は個別に細かく、ローカルでチェックしたい人向け。 結果が気になると、その分調べる量が増える点に注意。 ■12の暗号化方式で問題ないこと、16の暗号化方式で失敗したことを確認。 $ sudo openssl ciphers -V 'HIGH:!aNULL' | awk '!/SSLv3/{print $3}' | \ for CIPHER in `xargs`;do \ echo -e "GET / HTTP/1.0\n\n" | \ openssl s_client -no_ssl2 -no_ssl3 -no_tls1 -connect 172.31.31.254:443 -cipher $CIPHER -msg 2>&1 | \ grep '^New, (' | xargs echo $CIPHER; \ done | awk '{if(/NONE/){NG+=1;print $1,"NG"}else{OK+=1;print $1,"OK"}}END{print "OK="OK,"NG="NG}' ECDHE-RSA-AES256-GCM-SHA384 OK ECDHE-ECDSA-AES256-GCM-SHA384 NG ECDHE-RSA-AES256-SHA384 OK ECDHE-ECDSA-AES256-SHA384 NG DHE-DSS-AES256-GCM-SHA384 NG DHE-RSA-AES256-GCM-SHA384 OK DHE-RSA-AES256-SHA256 OK DHE-DSS-AES256-SHA256 NG ECDH-RSA-AES256-GCM-SHA384 NG ECDH-ECDSA-AES256-GCM-SHA384 NG ECDH-RSA-AES256-SHA384 NG ECDH-ECDSA-AES256-SHA384 NG AES256-GCM-SHA384 OK AES256-SHA256 OK ECDHE-RSA-AES128-GCM-SHA256 OK ECDHE-ECDSA-AES128-GCM-SHA256 NG ECDHE-RSA-AES128-SHA256 OK ECDHE-ECDSA-AES128-SHA256 NG DHE-DSS-AES128-GCM-SHA256 NG DHE-RSA-AES128-GCM-SHA256 OK DHE-RSA-AES128-SHA256 OK DHE-DSS-AES128-SHA256 NG ECDH-RSA-AES128-GCM-SHA256 NG ECDH-ECDSA-AES128-GCM-SHA256 NG ECDH-RSA-AES128-SHA256 NG ECDH-ECDSA-AES128-SHA256 NG AES128-GCM-SHA256 OK AES128-SHA256 OK OK=12 NG=16 ■エラーの詳細はgrepを外して見て個別に調査するものとして。。。 $ sudo openssl ciphers -V 'HIGH:!aNULL' | awk '!/SSLv3/{print $3}' | \ for CIPHER in `xargs`;do \ echo -e "GET / HTTP/1.0\n\n" | \ openssl s_client -no_ssl2 -no_ssl3 -no_tls1 -connect 172.31.31.254:443 -cipher $CIPHER -msg 2>&1 | \ grep '^New, (' | xargs echo $CIPHER; \ done | awk '{if(/NONE/){NG+=1;print $1,"NG"}else{OK+=1;print $1,"OK"}}END{print "OK="OK,"NG="NG}' | \ grep NG | awk '{print $1}' | \ for CIPHER in `xargs`;do \ echo -e "GET / HTTP/1.0\n\n" | \ openssl s_client -no_ssl2 -no_ssl3 -no_tls1 -connect 172.31.31.254:443 -cipher $CIPHER -debug 2>&1 ; \ done | grep "^[0-9].*error" 140485668755088:error:14077410:SSL routines:SSL23_GET_SERVER_HELLO:sslv3 alert handshake failure:s23_clnt.c:770: 139997613799056:error:14077410:SSL routines:SSL23_GET_SERVER_HELLO:sslv3 alert handshake failure:s23_clnt.c:770: 140204113753744:error:14077410:SSL routines:SSL23_GET_SERVER_HELLO:sslv3 alert handshake failure:s23_clnt.c:770: 140306475337360:error:14077410:SSL routines:SSL23_GET_SERVER_HELLO:sslv3 alert handshake failure:s23_clnt.c:770: 139896995436176:error:14077410:SSL routines:SSL23_GET_SERVER_HELLO:sslv3 alert handshake failure:s23_clnt.c:770: 140571312961168:error:14077410:SSL routines:SSL23_GET_SERVER_HELLO:sslv3 alert handshake failure:s23_clnt.c:770: 140484783466128:error:14077410:SSL routines:SSL23_GET_SERVER_HELLO:sslv3 alert handshake failure:s23_clnt.c:770: 140225213290128:error:14077410:SSL routines:SSL23_GET_SERVER_HELLO:sslv3 alert handshake failure:s23_clnt.c:770: 140227260216976:error:14077410:SSL routines:SSL23_GET_SERVER_HELLO:sslv3 alert handshake failure:s23_clnt.c:770: 139897304012432:error:14077410:SSL routines:SSL23_GET_SERVER_HELLO:sslv3 alert handshake failure:s23_clnt.c:770: 140707123160720:error:14077410:SSL routines:SSL23_GET_SERVER_HELLO:sslv3 alert handshake failure:s23_clnt.c:770: 139740867552912:error:14077410:SSL routines:SSL23_GET_SERVER_HELLO:sslv3 alert handshake failure:s23_clnt.c:770: 139873656866448:error:14077410:SSL routines:SSL23_GET_SERVER_HELLO:sslv3 alert handshake failure:s23_clnt.c:770: 139968604477072:error:14077410:SSL routines:SSL23_GET_SERVER_HELLO:sslv3 alert handshake failure:s23_clnt.c:770: 139734951499408:error:14077410:SSL routines:SSL23_GET_SERVER_HELLO:sslv3 alert handshake failure:s23_clnt.c:770: 139835136349840:error:14077410:SSL routines:SSL23_GET_SERVER_HELLO:sslv3 alert handshake failure:s23_clnt.c:770: 140435192239760:error:1410D0B9:SSL routines:SSL_CTX_set_cipher_list:no cipher match:ssl_lib.c:1295: ■例えばRC4が無効であることの確認。 $ sudo openssl ciphers -V | awk '/RC4/{print $3}' | \ for CIPHER in `xargs`;do \ echo -e "GET / HTTP/1.0\n\n" | \ openssl s_client -no_ssl2 -no_ssl3 -no_tls1 -connect 172.31.31.254:443 -cipher $CIPHER -msg 2>&1 | \ grep '^New, (' | xargs echo $CIPHER; \ done | awk '{if(/NONE/){NG+=1;print $1,"NG"}else{OK+=1;print $1,"OK"}}END{print "OK="OK,"NG="NG}' ECDHE-RSA-RC4-SHA NG ECDHE-ECDSA-RC4-SHA NG ECDH-RSA-RC4-SHA NG ECDH-ECDSA-RC4-SHA NG RC4-SHA NG RC4-MD5 NG PSK-RC4-SHA NG OK= NG=7
