From patchwork Sun Sep 9 03:11:51 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Peter_M=C3=BCller?= X-Patchwork-Id: 1912 Return-Path: Received: from mail01.ipfire.org (mail01.ipfire.org [IPv6:2001:470:7183:25::1]) by web02.i.ipfire.org (Postfix) with ESMTP id C753860721 for ; Sat, 8 Sep 2018 19:12:02 +0200 (CEST) Received: from mail01.i.ipfire.org (localhost [IPv6:::1]) by mail01.ipfire.org (Postfix) with ESMTP id 1306D10C14BB; Sat, 8 Sep 2018 18:12:02 +0100 (BST) Received: from mx-nbg.link38.eu (mx-nbg.link38.eu [37.120.167.53]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "mx-nbg.link38.eu", Issuer "Let's Encrypt Authority X3" (verified OK)) by mail01.ipfire.org (Postfix) with ESMTPS id 49FBA108DA37 for ; Sat, 8 Sep 2018 18:11:59 +0100 (BST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=link38.eu; s=201803; t=1536426711; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding:in-reply-to: references; bh=K3Z4+284Lqqn/fKnm31W5MXAjxpzdT58qsB3GCmS1SY=; b=FM4S16LO12M0dg000LQ/iI6AYZlNcVnzOI91wM7M9B3Qqf0e4xiy8Ubc0rZu/KaU/eKf+4 t1pjbxwWS3rPvSXFE3xGiDPfZII/fiQLZYXWZXvuVMJ9EnmeWOLGH2DNyM6PFDqN6zEeg1 GoCcXqiYN3pAeZx3bKQiXarGx0bzPT62H2T0kyot2PGXbdVaFqClwABhMET4mgfOFcaY+3 X45aSx+b35ZY5rxnFxV5T86FmsnaOKEh/ZOcPtojwwAYvwYiz5hVarsONzDB2IjFyVy50o SD3hY9R+5GqVo7BuQuMrux1lTogHIGsFiatPgqFbDHr13ia3V9+HKg7rgGI61g== To: "IPFire: Development-List" From: =?utf-8?q?Peter_M=C3=BCller?= Openpgp: preference=signencrypt Autocrypt: addr=peter.mueller@link38.eu; prefer-encrypt=mutual; keydata= xsFNBFrlh/UBEADDNM0LnM9+1NhjgfIz7Ww9Hlx6egK75TJoVa/S9gjI+3DeXn7hsj7vZnQz qSXMhSauU7k4g+F+MmOJP2HRIl0lEo/JNrpAqrAseSnbJp4eq8OTyAL6+Z3SVNJNbcRDOHmw jb/GR8ncURcgYDYV+oCs4csrghtBnm4cWaD/RW10zlB4nQsqQ5G3jzY9aIM+NKRHSAZEbXBZ W6pyDcGRMkwSFTHXpjtFDZ6mVEMxi1nv2W8PMU+uGbs3ud4gzPZ0tT5ICR8bp71qpua4r4RQ o6rB/suiPOptOE5/rk8FiW3ho0y1xDu7bRx8UzdLS9cYCVeSvf9n9YZ6RGOH9O7dS23zfTkS 8iqYol1PmVZrNtpsWBCq4HzFtRJPs6gykFNfj2sVQXU3RHHf2ui0OKm3R0olhLVbKSw2qSPM ajP1vBuVLEMSJmucxlJQ72Im/afnOz3LlNt+/FOB0zneoKGvPpPGSP/Fr5FJYED6/l1DZl2W 8Wb76xq3HGfETHW9kwwqbbQefMu6LNQIw9CnTpSk/R9mt7AnIrKCjxfclLDfz6VBJ0grRDDF PBEVBrj7uZM0UCl/dUX0adjDxBfma/UJZcBlDVX61+41vsX6w094sveKaNdqybAIxqGnhRUq kCHm5P/IYOZrtkao/TsRIW508MJBGmxoUl2qqCj7tXtNy2tiUQARAQABzSdQZXRlciBNw7xs bGVyIDxwZXRlci5tdWVsbGVyQGxpbmszOC5ldT7CwX8EEwECACkFAlrlh/UCGyMFCQlmAYAH CwkIBwMCAQYVCAIJCgsEFgIDAQIeAQIXgAAKCRDZSPIPfXufaDlVD/0elAwSohcC4T5jFtPt hZ1+jU9t46pwBhQ8ohKpo4/wAuVBg5B0FYb0gegcSicYWsNkhTtCjUhExMilLKTaJir5l+3V B/rU/WG7NgLYqmYsGlgHPXdLZAbOMU/0atONFYos1UZnRGmPfhLwRw3g5TBaKrfqaFBzRABE W0R+XuRoXy9ho+lNP5g0Sa+SxtOeBpLQxppObk5WLUqDKxrvHhStgM3PrJASKujsJiw19IUg ws0q+WezH8LPQd3Vc8DP56sl1/h8w2Xklsdxj1NEcO7OIrrKSNIRGyqgqvtmDi6dxh1suGUW Par/VhB+P+u0yVy8H1lZ4SFUsZJFPwHNFSN41USmT/uHf9Z7K1+qXm4zpyexrDQ+ojuXxnB1 y97cHYcYaCZ2Bo+deljXng1NF0I3CdIdhPfLv7FHRBoBw1xs0qJjUfTfSAZsYD0H/jl76bRx 4s8rrECqM7pMnE4aLiP4m6gKJKooH8QAQsmGRYAI8gG/BIHPHZUpZ8J2jRnj6GQ1MpEdcnLE Q0N7QMayDoPq177es7tey5vzofq3bDGW/O9yqUWiz3e7uaGSQnYoRGm2oCCTojvGt37yS0H8 v+ms2fokPNt8UDmpZoLFFPXDwVcnL/KBkPY665xchatKpBOtJ3lRnXdlyRJW1gGda9G5mGFn xLcWumkZ12YKmtixuM7BTQRa5Yf1ARAA4UCkVBvQhks9lApBxvfZ8ekWrticMooBkegL+KQT TPWQHTgdwkFzSneaRq0vFFcgKxmXA54OmT58y0tf09hUvTGK4COs5GTZKP/SYSWZM6xOQqaT 37fros/ma4iSS+IJw/eDh7bWKM5gllz0EuoewaTveGDWeucf7V36mRUPG47GsNk/PgCRsO5Y SLlpfT/3xH02aRnUmWjzHCkJ9EV388cIWaYo9kP4q9rbcl3IyHP0t78XpIIWH6+o/I0FgzwL GJBdJ0eAE3PNIRGYu8nqYlJ+TIpcIrEPitma6nZtiWAITRO2XDb/2o05tUlEbmlN6dUOqM7X Jvj/Z9KkYNgvYNbHXqXJ+j5gzcq0DR7DtDSDnd1WDrYivQMGBDnZR2YfFjBEsmeArdmDTZqY aqYhBN3iMCI9cErZgik6Niz6jrqBMK98geB04vrqZUYprh7zXgPu0A/EwTIJuZ+GGeEKwMVL pBc2NGxUb/kt8nr1JHAnSludD78EW6QVdpcgO4DhHxzhdDk/L8yE53b5UdvXwad5N4T1QS/Y kk80nByinD4vaIIHti9nOvLQJAro1p997YnVeY0wQ2x14Qw1rqeCOeKqB8PxmHvSK6b+nXLg Dv7HuFLovIeQd/IimGLXBDW4Bkn60HApJ5KcX+GwHp5XqPRKPmtjfMsETZn1ESjyc3sAEQEA AcLBZQQYAQIADwUCWuWH9QIbDAUJCWYBgAAKCRDZSPIPfXufaBRaEACMS5Q1BY/O5o+Vn8lD uMUczEVk/8j07gi1EV2ffutwZ5eYrKvXkuoMPEBb7SWqPUKqpTbw1pNjUf5002c2xm2r/OSZ oQMRWDztht+EMhjy0qkixMV+TvS6DcFPb8sd+KOoIBD08EBVUxpeNhAFxaRjGEDboJUwtDAd EDUJts5HnXvBqEcnkOfkwDSUWf9epa1mbyO1sO5NnMtxQY6paB2UGQPNE5/J3eo4f5s4wrxR AaM6OCCOtJxs4u0svmOCwd0D8LQ6higBq+EFesc57ZpG3pkNokrROFWRpx6OpQJUnYi5lWm8 +4xF99QfI9mHIz+jrnPcsfAiKdXb8QkeaDkR7bIU269wwKupfN6bHsKFtOnx7AhMLUddzTHA hTe8cov/tnn5xPvSZhpfknOBx+mffNQBsCETuCxPMqtDN5xFuwBxw4ZKZpKYFk/FUl6As1z4 LY2tNXb/JI58fGiLreunuvxsEkb97hmly1e19IPOTJzawB/aKRQNpIkoE11UBhKyc+kwIfVo ZCTlp+3hpBFqxEjRReSQUKKb9hA4yP3j90Fb353JbNKf9+Y3UtFPJb67koDOGtbJsk19bzPE zO0j/ek+eXxTIf5NxURVuzY6yvg57ZzW7T/tApT/LLfMEmuYz/LiijgON0uTOSp8KflwAt8m eNtEia+FigGVqn+PSQ== Subject: [PATCH 1/2] add hardened SSH client configuration Message-ID: <21bde1af-9026-b630-7370-c1f0f4abc07e@link38.eu> Date: Sat, 8 Sep 2018 19:11:51 +0200 MIME-Version: 1.0 Content-Language: en-GB Authentication-Results: mail01.ipfire.org; dkim=pass header.d=link38.eu; dmarc=pass (policy=none) header.from=link38.eu; spf=pass smtp.mailfrom=peter.mueller@link38.eu X-Spamd-Result: default: False [-12.54 / 11.00]; ARC_NA(0.00)[]; R_DKIM_ALLOW(-0.20)[link38.eu]; BAYES_HAM(-3.00)[100.00%]; FROM_HAS_DN(0.00)[]; R_SPF_ALLOW(-0.20)[+ip4:37.120.167.53]; TO_MATCH_ENVRCPT_ALL(0.00)[]; MIME_GOOD(-0.10)[text/plain]; RCPT_COUNT_ONE(0.00)[1]; TO_DN_ALL(0.00)[]; DKIM_TRACE(0.00)[link38.eu:+]; DMARC_POLICY_ALLOW(-0.25)[link38.eu,none]; MX_GOOD(-0.01)[cached: mx-nbg.link38.eu]; NEURAL_HAM(-2.99)[-0.997,0]; RCVD_IN_DNSWL_MED(-2.00)[53.167.120.37.list.dnswl.org : 127.0.6.2]; RCVD_COUNT_ZERO(0.00)[0]; FROM_EQ_ENVFROM(0.00)[]; IP_SCORE(-3.78)[ip: (-9.91), ipnet: 37.120.160.0/19(-4.96), asn: 197540(-3.96), country: DE(-0.09)]; ASN(0.00)[asn:197540, ipnet:37.120.160.0/19, country:DE]; MID_RHS_MATCH_FROM(0.00)[]; RCVD_TLS_ALL(0.00)[] X-Spam-Status: No, score=-12.54 X-Rspamd-Server: mail01.i.ipfire.org X-BeenThere: development@lists.ipfire.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: IPFire development talk List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: development-bounces@lists.ipfire.org Sender: "Development" Introduce a custom OpenSSH client configuration file for IPFire. Some people use it as a jumping host, so applying hardening options system-wide improves security. Cryptography setup is the same as for OpenSSH server configuration. Partially fixes #11751 Signed-off-by: Peter Müller --- config/ssh/ssh_config | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) create mode 100644 config/ssh/ssh_config diff --git a/config/ssh/ssh_config b/config/ssh/ssh_config new file mode 100644 index 000000000..eadf307ee --- /dev/null +++ b/config/ssh/ssh_config @@ -0,0 +1,33 @@ +# OpenSSH client configuration +# +# set some basic hardening options for all connections +Host * + # disable Roaming as it is known to be vulnerable + UseRoaming no + + # only use secure crypto algorithm + KexAlgorithms curve25519-sha256@libssh.org,diffie-hellman-group-exchange-sha256 + Ciphers chacha20-poly1305@openssh.com,aes256-gcm@openssh.com,aes128-gcm@openssh.com + MACs hmac-sha2-512-etm@openssh.com,hmac-sha2-256-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-512,hmac-sha2-256,umac-128@openssh.com + + # always visualise server host keys (has no technical + # effect, but helps to identify MITM attacks) + VisualHostKey yes + + # use SSHFP (might work on some up-to-date networks) to look up host keys + VerifyHostKeyDNS yes + + # send keep-alive messages to connected server to avoid broken connections + ServerAliveInterval 10 + ServerAliveCountMax 6 + + # disable X11 forwarding (security risk) + ForwardX11 no + + # always check server IP address + CheckHostIP yes + + # ensure only allowed authentication methods are used + PreferredAuthentications publickey,keyboard-interactive,password + +# EOF