From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Jean Louis Newsgroups: gmane.emacs.help Subject: Re: Let us see how to encrypt with Emacs? Date: Fri, 9 Jul 2021 14:32:10 +0300 Message-ID: References: <83mtqvdb4s.fsf@gnu.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="19901"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Mutt/2.0.7+183 (3d24855) (2021-05-28) Cc: help-gnu-emacs@gnu.org To: Eli Zaretskii Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Fri Jul 09 13:35:43 2021 Return-path: Envelope-to: geh-help-gnu-emacs@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1m1onH-000535-OX for geh-help-gnu-emacs@m.gmane-mx.org; Fri, 09 Jul 2021 13:35:43 +0200 Original-Received: from localhost ([::1]:58758 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1m1onG-0003E5-Q1 for geh-help-gnu-emacs@m.gmane-mx.org; Fri, 09 Jul 2021 07:35:42 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:41416) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m1omJ-00039U-Dq for help-gnu-emacs@gnu.org; Fri, 09 Jul 2021 07:34:43 -0400 Original-Received: from stw1.rcdrun.com ([217.170.207.13]:42219) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m1omH-0002gl-F2; Fri, 09 Jul 2021 07:34:43 -0400 Original-Received: from localhost ([::ffff:197.157.34.164]) (AUTH: PLAIN admin, TLS: TLS1.3,256bits,ECDHE_RSA_AES_256_GCM_SHA384) by stw1.rcdrun.com with ESMTPSA id 0000000000057EBC.0000000060E8342D.000031BA; Fri, 09 Jul 2021 04:34:05 -0700 Mail-Followup-To: Eli Zaretskii , help-gnu-emacs@gnu.org Content-Disposition: inline In-Reply-To: <83mtqvdb4s.fsf@gnu.org> Received-SPF: pass client-ip=217.170.207.13; envelope-from=bugs@gnu.support; helo=stw1.rcdrun.com X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: help-gnu-emacs@gnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Users list for the GNU Emacs text editor List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Original-Sender: "help-gnu-emacs" Xref: news.gmane.io gmane.emacs.help:131633 Archived-At: * Eli Zaretskii [2021-07-09 13:40]: > > (setq encrypted (gnutls-symmetric-encrypt "CHACHA20-64" (string-pad "MyPassword987" 32) (make-string 16 (random 100)) (string-pad "Text to encrypt" 64))) > > > > And I can decrypt it: > > > > (car (gnutls-symmetric-decrypt "CHACHA20-64" (string-pad "MyPassword987" 32) (cadr encrypted) (car encrypted))) ⇒ "Text to encrypt " > > > > but that is not well integrated for practical encryption as I > > have to employ padding even for string to be encrypted, and > > chunking of string to 64 bytes. > > No, you don't need to chunk, you just need to pad to a multiple of 64 > bytes. I guess something like this unless I am making an error: (defun pad-to-multiple-bytes (string max) "Return string padded to multiple of MAX bytes." (let* ((bytes (string-bytes string)) (multiple (truncate (/ bytes max))) (multiple (if (zerop multiple) max (* (1+ multiple) max)))) (string-pad string multiple))) > What kind of help? To use these functions, you need to learn about > the various ciphers and what they require. This is something the > Emacs Lisp reference manual cannot teach you. > > > ‘STRING’ > > A string as input will be used directly. It may be modified by the > > function (unlike most other Emacs Lisp functions) to reduce the > > chance of exposing sensitive data after the function does its work. > > > > I am trying to use list with STRING as following and that does not work: > > > > (gnutls-symmetric-encrypt "CHACHA20-64" (string-pad "MyPassword987" 32) (make-string 16 (random 100)) '(STRING "Text to encrypt")) > > What do you mean by "does not work"? I get invalid object argument: STRING so I do not understand how to use STRING there. Jean Take action in Free Software Foundation campaigns: https://www.fsf.org/campaigns In support of Richard M. Stallman https://stallmansupport.org/