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) server-digest SHA256) (No client certificate requested) by lists.proxmox.com (Postfix) with ESMTPS id 2A8C0935CA for ; Mon, 20 Feb 2023 10:40:32 +0100 (CET) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id 10DC924BBF for ; Mon, 20 Feb 2023 10:40:32 +0100 (CET) Received: from proxmox-new.maurer-it.com (proxmox-new.maurer-it.com [94.136.29.106]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by firstgate.proxmox.com (Proxmox) with ESMTPS for ; Mon, 20 Feb 2023 10:40:31 +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 15E6F47C32 for ; Mon, 20 Feb 2023 10:40:31 +0100 (CET) Message-ID: <4472e05c-bac9-17bc-6972-a8788bbef119@proxmox.com> Date: Mon, 20 Feb 2023 10:40:29 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.6.0 Content-Language: en-US To: Thomas Lamprecht , Proxmox VE development discussion References: <20230217152517.84874-1-m.carrara@proxmox.com> From: Max Carrara In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-SPAM-LEVEL: Spam detection results: 0 AWL 0.075 Adjusted score from AWL reputation of From: address BAYES_00 -1.9 Bayes spam probability is 0 to 1% KAM_DMARC_STATUS 0.01 Test Rule for DKIM or SPF Failure with Strict Alignment NICE_REPLY_A -0.09 Looks like a legit reply (A) SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record SPF_PASS -0.001 SPF: sender matches SPF record Subject: Re: [pve-devel] [PATCH http-server 0/2] refactor HTTP request processing X-BeenThere: pve-devel@lists.proxmox.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Proxmox VE development discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 20 Feb 2023 09:40:32 -0000 On 2/17/23 18:15, Thomas Lamprecht wrote: > Am 17/02/2023 um 16:25 schrieb Max Carrara: >> This patch series refactors the request processing algorithm by >> separating its data and logic from one another in order to make future >> changes regarding requests more transparent and explicit. >> >> Patch 1: Introduce the refactored algorithm >> Patch 2: Replace and remove the existing algorithm with the new one > > See not much benefit in having this split into two patches in this way, > constructing (one or ideally more) patches such that the refactored (out) > code is directly put to use in(stead of) it's old place has normally more > benefits, even if just allows one to see what actually moved (e.g., using > the `--color-moved=zebra --color-moved-ws=ignore-all-space` git switches) > > But no need to resend now, I can squash locally for doing a more in-depth > review first. Alright, noted! Will keep that in mind. >> This refactor is conducted very carefully to ensure that none of the >> existing behaviours change in any way. > > Careful as in? ^^ Doesn't seem to be a very conservative "just split up", > but more involved; and there isn't any testing added to ensure the changes > don't mess with semantics - which tbf might not be the easiest thing to do > in a sensible manner, that is actually covering a lot, here. > > But especially header parsing with some edge cases could be quite nicely > done with the respective request methods mocked. Mocking in which way exactly? Via `curl` or similar, or via separate tests? If I should add (Perl) tests, where should I put them and how are they best implemented? >> One exception however would be >> the reading of the HTTP header itself: Instead of reading the >> header by recursively appending / prepending callbacks to the handle's >> and reading the header line-by-line, the entire header is read at >> once, reducing the number of callbacks needed to parse the header from >> the number of lines to one. This affects when the header line count >> and size limits are checked - instead of being checked *while* the >> header is being read, these limits are verified *after* the header >> was read from the read buffer. If this change in behaviour is >> undesirable, I'll gladly provide a v2. > > that seems to make those limits mostly (i.e., besides maybe proxied > requests) irrelevant though? If one spent all of the resources to process > a huge header fully it doesn't makes sense to only then die if it's deemed > to big. > > But again, I'd wait out for a more in-depth review before going on a v2. Very fair point - I hadn't viewed it as too problematic in this case, because HTTP headers rarely get that big anyway, don't they? >> Otherwise, the behaviour is identical; the logic is restructured, >> but entirely preserved. >> >> >> To give a more concrete example of what these changes would make more >> transparent, the enhancement requested in #4494[1] would become just >> another step (-> subroutine) in the refactored algorithm. That way it >> becomes much clearer where the TLS handshake is being verified >> and which responses (e.g. a `301`) are sent in case the handshake >> never happened or was aborted. > > A patch, even if just POC, would be a more concrete example ;-) that could > then _actually_ show that the changes actually provide a nicer interface to > extend. Sure! I'll send one in.