From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [216.205.24.124]) by sourceware.org (Postfix) with ESMTP id 653643969014 for ; Thu, 5 Aug 2021 16:54:07 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 653643969014 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-133--MAS1-txOEKZZ-CARbeM8w-1; Thu, 05 Aug 2021 12:54:05 -0400 X-MC-Unique: -MAS1-txOEKZZ-CARbeM8w-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id AB9D9801AC0; Thu, 5 Aug 2021 16:54:04 +0000 (UTC) Received: from redhat.com (ovpn-112-63.phx2.redhat.com [10.3.112.63]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 6C2C23CC7; Thu, 5 Aug 2021 16:54:04 +0000 (UTC) Received: from fche by redhat.com with local (Exim 4.94.2) (envelope-from ) id 1mBgd8-00062S-QH; Thu, 05 Aug 2021 12:54:02 -0400 Date: Thu, 5 Aug 2021 12:54:02 -0400 From: "Frank Ch. Eigler" To: Mark Wielaard Cc: Noah Sanci , elfutils-devel@sourceware.org Subject: Re: [Bug debuginfod/27277] Describe retrieved files when verbose Message-ID: <20210805165402.GD4195@redhat.com> References: MIME-Version: 1.0 In-Reply-To: User-Agent: Mutt/1.12.0 (2019-05-25) X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-Spam-Status: No, score=-6.8 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, RCVD_IN_DNSWL_LOW, RCVD_IN_MSPIKE_H3, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_NONE, TXREP autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: elfutils-devel@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Elfutils-devel mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 05 Aug 2021 16:54:10 -0000 Hi - > I like the verbose http header output, but wish it was done earlier > instead of after the download. Maybe when we commit to an url, if the > info is available then. What do you mean "done"? Printed? > The new X-FILE and X-ARCHIVE headers also seem useful. > One question about X-FILE, if it doesn't come from an archive, does it > leak a file system path that might be "secret" on the server? Perhaps kind of sort of ... but since source files for such buildids are resolved only against the host filesystem, those same names will be there in all their glory in the DWARF. My guess is that public servers that care about such configuration privacy will be exclusively archive based. > Why is X-FILE-SIZE != Content-Length ? Because Content-Length can be shorter due to compression transfer-encoding. It's the file size that governs local storage & DEBUGINFOD_MAXSIZE interaction. > I am less enthusiastic about the new debuginfod_get_response_headers > interface. It seems not as useful since it only works if we haven't > already (negatively) cached the file and it is very free-form, do we > guarantee any headers are there? Naturally we can't guarantee any headers, because they are at the pleasure of the server. > Could you provide a user story where this is used? Not really, beyond just printing the things for information purposes, but not wanting the whole DEBUGINFOD_VERBOSE=1 firehose. In the mid term, it could help systemd-coredumpctl type tools map buildids to actual distro artifact names, and enable paranoid federation/buildtree/checking type measures (where we may want to spot-check servers that buildids haven't been hijacked). Vague but I think there's something there. > Maybe this interface is more useful if it was done as a new active > query type (the HEAD query you mention in the commit message)? That in turn would require THREE new API functions or a stateful set_HEAD_mode_and_return_dev_null one and modifying the three main lookup functions. - FChE