From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from firstgate.proxmox.com (firstgate.proxmox.com [212.224.123.68]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by lists.proxmox.com (Postfix) with ESMTPS id B9AB260B08 for ; Wed, 18 Nov 2020 09:01:43 +0100 (CET) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id B01D11853B for ; Wed, 18 Nov 2020 09:01:13 +0100 (CET) Received: from proxmox-new.maurer-it.com (proxmox-new.maurer-it.com [212.186.127.180]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by firstgate.proxmox.com (Proxmox) with ESMTPS id EB9C018530 for ; Wed, 18 Nov 2020 09:01:12 +0100 (CET) Received: from proxmox-new.maurer-it.com (localhost.localdomain [127.0.0.1]) by proxmox-new.maurer-it.com (Proxmox) with ESMTP id B18A843937 for ; Wed, 18 Nov 2020 09:01:12 +0100 (CET) To: Dominik Csapak , Dietmar Maurer , pmg-devel@lists.proxmox.com References: <20201117145743.10561-1-d.csapak@proxmox.com> <925752189.205.1605630434708@webmail.proxmox.com> <536187425.206.1605631117830@webmail.proxmox.com> <31d52e9d-fe70-acdb-b24c-3554df4c3b13@proxmox.com> From: Thomas Lamprecht Message-ID: <8f45432a-305c-31a6-954b-f45dd6effff3@proxmox.com> Date: Wed, 18 Nov 2020 09:01:11 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:83.0) Gecko/20100101 Thunderbird/83.0 MIME-Version: 1.0 In-Reply-To: <31d52e9d-fe70-acdb-b24c-3554df4c3b13@proxmox.com> Content-Type: text/plain; charset=UTF-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable X-SPAM-LEVEL: Spam detection results: 0 AWL -0.087 Adjusted score from AWL reputation of From: address KAM_DMARC_STATUS 0.01 Test Rule for DKIM or SPF Failure with Strict Alignment NICE_REPLY_A -0.001 Looks like a legit reply (A) RCVD_IN_DNSWL_MED -2.3 Sender listed at https://www.dnswl.org/, medium trust SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record SPF_PASS -0.001 SPF: sender matches SPF record URIBL_BLOCKED 0.001 ADMINISTRATOR NOTICE: The query to URIBL was blocked. See http://wiki.apache.org/spamassassin/DnsBlocklists#dnsbl-block for more information. [wikipedia.org] Subject: Re: [pmg-devel] [PATCH pmg-api/gui] add quarantine self service button X-BeenThere: pmg-devel@lists.proxmox.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Proxmox Mail Gateway development discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 18 Nov 2020 08:01:43 -0000 On 18.11.20 08:56, Dominik Csapak wrote: > On 11/18/20 8:44 AM, Thomas Lamprecht wrote: >> On 17.11.20 17:38, Dietmar Maurer wrote: >>> >>>> On 11/17/2020 5:27 PM Dietmar Maurer wrote: >>>> >>>> =C2=A0 IMHO this is too dangerous. >>>> >>>> This needs at least some kind of captcha ... >>> >>> i.e. This would allow direct DOS attacks to the internal mail server.= >>> >> >> I found this captcha solution, relatively sophisticated but not a PITA= for the >> (human) user, Friendly Captcha[0] used by some official European Union= websites. >> >> It uses Proof of Work[2] (i.e. crypto puzzel ones device needs to solv= e by >> computation), the specific library used is "Friendly PoW"[1]. >> >> If we go for a captcha I'd like something like this (could be rebuild)= , as >> it avoids the issues with picture texts (easily solved by computers, b= ad >> accessibility for humans) and similar captchas. >> >> >> [0]: https://github.com/friendlycaptcha/friendly-challenge >> [1]: https://github.com/friendlycaptcha/friendly-pow >> [2]: https://de.wikipedia.org/wiki/Proof_of_Work >> >=20 > i'd rather go with a rate limited approach > e.g. a file with a > mail -> last click time > mapping > and refuse if the last click time is not older than 5min ? > and only 1 per 5 seconds overall? or an hour or day? what do you need the mail such often?? The ticket doesn't even expires that fast.. >=20 > a captcha would be much harder to implement (more dependencies, > backend as well as dependent frontend code and in this example > it seems the code is only available for js/ts), though > if we find a simple solution, i am not against it >=20 but also more efficient, as the client actually needs to put in work. JS is no problem, the backend would be nice in rust or so - maybe in the future when someone gets around some day...