From owner-freebsd-security Sun May 2 23:22:31 1999 Delivered-To: freebsd-security@freebsd.org Received: from beatrice.rutgers.edu (beatrice.rutgers.edu [165.230.209.226]) by hub.freebsd.org (Postfix) with ESMTP id 554C214C9E for ; Sun, 2 May 1999 23:22:29 -0700 (PDT) (envelope-from easmith@beatrice.rutgers.edu) Received: (from easmith@localhost) by beatrice.rutgers.edu (980427.SGI.8.8.8/970903.SGI.AUTOCF) id CAA06444; Mon, 3 May 1999 02:05:30 -0400 (EDT) From: "Allen Smith" Message-Id: <9905030205.ZM6442@beatrice.rutgers.edu> Date: Mon, 3 May 1999 02:05:30 -0400 In-Reply-To: Robert Watson "Re: Blowfish/Twofish" (May 3, 1:58am) References: X-Mailer: Z-Mail (3.2.3 08feb96 MediaMail) To: Robert Watson , 0x1c Subject: Re: Blowfish/Twofish Cc: freebsd-security@FreeBSD.ORG Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: owner-freebsd-security@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org On May 3, 1:58am, Robert Watson (possibly) wrote: > > I don't believe so, as long as they are not just crypto algorithms. I.e., > I believe our DES hashing is not exportable, whereas our MD5 hashing is. > In a sense, it's all a matter of perspective on how you use an algorithm. > It's all just mathematics, right? Sort of like you can't patent > mathematical formulas, but you can patent algorithms. :) So SHA-1 support > for FreeBSD would be quite exportable, I'd imagine, and would probably > make a worthwhile addition. I don't see Blowfish as a great addition > other than the interoperability concerns expressed previously. > On Mon, 3 May 1999, 0x1c wrote: > > > On a similar note, is there any restriction on one-way hashing algorithms? > > I forget. > > > > Nick One can use any cryptographically secure one-way hash function as a (secret key) encryption method. The procedure is as follows: Sender and recipient have shared secret key K. They want to transmit information I. Sender takes three-bit chunks (the most efficient size) of information I, finds a random salt S of sufficient size for each chunk, and does: hash(K S I-chunk) then sends the result and the random salt to the recipient. Recipient then looks for the 2-bit combination that hashed as above along with the secret and the key gives the result. -Allen -- Allen Smith easmith@beatrice.rutgers.edu To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-security" in the body of the message