From patchwork Mon Aug 27 04:34:09 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: 1902 Return-Path: Received: from mail01.ipfire.org (mail01.i.ipfire.org [172.28.1.200]) by web02.i.ipfire.org (Postfix) with ESMTP id 4DBAC60B0D for ; Sun, 26 Aug 2018 20:34:24 +0200 (CEST) Received: from mail01.i.ipfire.org (localhost [IPv6:::1]) by mail01.ipfire.org (Postfix) with ESMTP id 4011110FFF02; Sun, 26 Aug 2018 19:34:23 +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 7478910B0485 for ; Sun, 26 Aug 2018 19:34:19 +0100 (BST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=link38.eu; s=201803; t=1535308462; 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:in-reply-to: references; bh=1TuWLI3GC9IIWrVBQCoULYes/LFGVGHMamluoJIWp1w=; b=J6xKQrCXjkAH/MMMG89G9AnPugPLZeTvGSOulzK16sT6vqMUNe5OA8ot6nsqzoGZOdRTqV 9ZW74VFaoWmpkJz4R4PbA3kribhYajHf2yDydy7C8E/P582Vikth6YUzHrGTV/vcyZNiKz 9FThTjHK1bqn2OujmqRVeP1ez3VNivzeT+7eskgvdEkWFy17hLLV45jt8C9j7Z9U+vJZ91 6RstFHh1RBYBs1jDj5EiGgRr1BGBzc8Wp1NFor0QcY3frxGTYu0C0Hg1lILzKXbjUkpT1m aM4WVzxpTb3HhMz0RbCZaBuyuH81/1wMXjB4PCTJ8A6GDDnvQaRX0bQWqtkiww== To: "ipFire: Development-List" From: =?utf-8?q?Peter_M=C3=BCller?= Subject: [PATCH 1/3 v2] Unbound: Enable DNS cache poisoning mitigation 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== Message-ID: <58ca41ec-0a1a-68bd-1042-e8268926b807@link38.eu> Date: Sun, 26 Aug 2018 20:34:09 +0200 MIME-Version: 1.0 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 [-11.64 / 11.00]; ARC_NA(0.00)[]; BAYES_HAM(-3.00)[100.00%]; R_DKIM_ALLOW(-0.20)[link38.eu]; URIBL_BLOCKED(0.00)[nlnetlabs.nl.multi.uribl.com]; FROM_HAS_DN(0.00)[]; R_SPF_ALLOW(-0.20)[+ip4:37.120.167.53]; TO_MATCH_ENVRCPT_ALL(0.00)[]; HAS_ATTACHMENT(0.00)[]; MIME_GOOD(-0.20)[multipart/signed,multipart/mixed,text/plain]; RCPT_COUNT_ONE(0.00)[1]; TO_DN_ALL(0.00)[]; DKIM_TRACE(0.00)[link38.eu:+]; RCVD_IN_DNSWL_MED(-2.00)[53.167.120.37.list.dnswl.org : 127.0.6.2]; DMARC_POLICY_ALLOW(-0.25)[link38.eu,none]; MX_GOOD(-0.01)[cached: mx-nbg.link38.eu]; SIGNED_PGP(-2.00)[]; 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=-11.64 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" By default, Unbound neither keeps track of the number of unwanted replies nor initiates countermeasures if they become too large (DNS cache poisoning). This sets the maximum number of tolerated unwanted replies to 1M, causing the cache to be flushed afterwards. (Upstream documentation recommends 10M as a threshold, but this turned out to be ineffective against attacks in the wild.) See https://nlnetlabs.nl/documentation/unbound/unbound.conf/ for details. This version of the patch uses 1M as threshold instead of 5M and supersedes the first version. Signed-off-by: Peter Müller --- config/unbound/unbound.conf | 3 +++ 1 file changed, 3 insertions(+) diff --git a/config/unbound/unbound.conf b/config/unbound/unbound.conf index 3f724d8f7..fa2ca3fd4 100644 --- a/config/unbound/unbound.conf +++ b/config/unbound/unbound.conf @@ -61,6 +61,9 @@ server: harden-algo-downgrade: no use-caps-for-id: no + # Harden against DNS cache poisoning + unwanted-reply-threshold: 1000000 + # Listen on all interfaces interface-automatic: yes interface: 0.0.0.0