220 12452 <53F9DB1E.1020803@gmx.net> article Path: news.gmane.org!not-for-mail From: Jens Maurer Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Cryptographic hash functions reloaded [was Interest in cryptographic functions within the standard library] Date: Sun, 24 Aug 2014 14:31:26 +0200 Lines: 58 Approved: news@gmane.org Message-ID: <53F9DB1E.1020803@gmx.net> References: <53F8F620.3090701@gmx.de> <53F9AAF7.8030602@gmx.de> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 X-Trace: ger.gmane.org 1408883498 30427 80.91.229.3 (24 Aug 2014 12:31:38 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Sun, 24 Aug 2014 12:31:38 +0000 (UTC) To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBDPMTYGK64JRBINW46PQKGQEDLFBSQI@isocpp.org Sun Aug 24 14:31:31 2014 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-wi0-f200.google.com ([209.85.212.200]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1XLWxH-0005cF-6O for gclcip-std-proposals@m.gmane.org; Sun, 24 Aug 2014 14:31:31 +0200 Original-Received: by mail-wi0-f200.google.com with SMTP id d1sf711789wiv.11 for ; Sun, 24 Aug 2014 05:31:30 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:message-id:date:from:user-agent:mime-version:to :subject:references:in-reply-to:x-original-sender :x-original-authentication-results:reply-to:precedence:mailing-list :list-id:list-post:list-help:list-archive:list-subscribe :list-unsubscribe:content-type; bh=wrIt8r4q5GsN5r2akkLGEGLczV6Q2YHQpTr+/cF3vIU=; b=SVvT+D0dAPtJ8FH9ovW1B6I0K0J604fmJBVpYXScsVjtMPDrlqm4imaHLPJUO2ZYMh ZB+m2Qw9SDRfSfA/LBNKshuCP9I2fOEPubaJ8GaMm/fVYzx4dtMpyeP4Qh9tADpqhJ9F eEK7hmewqwGtUMaavjgFQ2c2LsddgSmMqkSSI3HD8QlXydCVnvV8/S6cgpQupdCXBob9 AWRFWX40vDv7pSLp/HKF+FigwkZFFcyKiLGVyGq2624WuHP3tbdIuU6kc1LPBMAQGD25 h/mOAyXo/rwl1E1SkmtBzn65kttsmgY9Q+K9wOWsivzYMG0oG1nhUujwYxBD9K7ujHsl VyLQ== X-Gm-Message-State: ALoCoQmNLawB5D+wxLeDW+A8y1L09G6v+Kq0ccUhAHwOcJv+UIFym5rYYWB4Qi8qs1h7jqEOU5om X-Received: by 10.180.198.172 with SMTP id jd12mr725516wic.6.1408883490506; Sun, 24 Aug 2014 05:31:30 -0700 (PDT) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.152.115.212 with SMTP id jq20ls16960lab.38.gmail; Sun, 24 Aug 2014 05:31:28 -0700 (PDT) X-Received: by 10.152.229.133 with SMTP id sq5mr2710504lac.67.1408883488903; Sun, 24 Aug 2014 05:31:28 -0700 (PDT) Original-Received: from mout.gmx.net (mout.gmx.net. [212.227.15.15]) by mx.google.com with ESMTPS id f2si9379563laf.0.2014.08.24.05.31.28 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sun, 24 Aug 2014 05:31:28 -0700 (PDT) Received-SPF: pass (google.com: domain of Jens.Maurer@gmx.net designates 212.227.15.15 as permitted sender) client-ip=212.227.15.15; Original-Received: from [192.168.2.100] ([178.7.39.200]) by mail.gmx.com (mrgmx002) with ESMTPSA (Nemesis) id 0Me8RK-1WytF00Yr0-00PuIc for ; Sun, 24 Aug 2014 14:31:28 +0200 User-Agent: Mozilla/5.0 (X11; Linux i686; rv:6.0.1) Gecko/20110830 Thunderbird/6.0.1 In-Reply-To: <53F9AAF7.8030602@gmx.de> X-Provags-ID: V03:K0:nR+iMtlVkmULBFL00fZq4OePg3HMu9KWWzZ7pTh+ZRAYAWg6oxd +VDp8B0LMVnxNkU5INULsYcA+NVzuG3UEI/bGudIukssOaCqLQtyy9kkYq+3wION6CzgYHl +0uIIezvAs9PoRcZtOCZjALnvlMJk0xwzckQfn4EZ5rRd09Ren8OS+UDXLPV/KJWWZI/bbR pv/mAGk/nBA4yYqOFzosg== X-UI-Out-Filterresults: notjunk:1; X-Original-Sender: Jens.Maurer@gmx.net X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of Jens.Maurer@gmx.net designates 212.227.15.15 as permitted sender) smtp.mail=Jens.Maurer@gmx.net Precedence: list Mailing-list: list std-proposals@isocpp.org; contact std-proposals+owners@isocpp.org List-ID: X-Google-Group-Id: 399137483710 List-Post: , List-Help: , List-Archive: List-Subscribe: , List-Unsubscribe: , Xref: news.gmane.org gmane.comp.lang.c++.isocpp.proposals:12452 Archived-At: On 08/24/2014 11:05 AM, Markus Mayer wrote: > class hash_function > { > public: > typedef std::array result_type; > //Default contructable > //Copyable > //Moveable > > hash_function& process_bytes( void unsigned char *buffer, std::size_t > byte_count); > > hash_function& operator() ( void unsigned char *buffer, std::size_t > byte_count); Remove the "void". Remove "process_bytes()", it's redundant. > void reset(); > > result_type hash_value() const; I've got a slight preference towards a named "result" function, but I can also live with the explicit conversion operator. > -How to hash a files? > Hashing a file is quite common. As the iterator interface was removed, > there is no easy way to hash a file (using istream_iterator). How to do > it now? Provide a thin wrapper template that processes input iterators in e.g. 1024-byte chunks. > -Should we only add some crc classes (like crc_32, crc_16 or crc_ccitt) > or a an generic (templated) crc algorithm (like in boost:crc)? I've no objection against providing a fully general CRC capability, but I'd like to see a typedef for at least crc32c, since Intel has a hardware instruction for this that asks for specialization. > -Find a suitable header file (maybe functional or algorithm) I'd be inclined to ask for a separate header file. Are there any legal restrictions on secure hash functions somewhere? There are definitely some for encryption algorithms in some places. Jens -- --- You received this message because you are subscribed to the Google Groups "ISO C++ Standard - Future Proposals" group. To unsubscribe from this group and stop receiving emails from it, send an email to std-proposals+unsubscribe@isocpp.org. To post to this group, send email to std-proposals@isocpp.org. Visit this group at http://groups.google.com/a/isocpp.org/group/std-proposals/. .