Date: Wed, 14 Dec 2016 15:30:55 -0800 From: Linus Torvalds <torvalds@...ux-foundation.org> To: "Jason A. Donenfeld" <Jason@...c4.com> Cc: Tom Herbert <tom@...bertland.com>, Netdev <netdev@...r.kernel.org>, "kernel-hardening@...ts.openwall.com" <kernel-hardening@...ts.openwall.com>, LKML <linux-kernel@...r.kernel.org>, Linux Crypto Mailing List <linux-crypto@...r.kernel.org>, Jean-Philippe Aumasson <jeanphilippe.aumasson@...il.com>, "Daniel J . Bernstein" <djb@...yp.to>, Eric Biggers <ebiggers3@...il.com>, David Laight <David.Laight@...lab.com> Subject: Re: [PATCH v3 1/3] siphash: add cryptographically secure hashtable function On Wed, Dec 14, 2016 at 2:56 PM, Jason A. Donenfeld <Jason@...c4.com> wrote: > > So actually jhash_Nwords makes no sense, since it takes dwords > (32-bits) not words (16-bits). The siphash analog should be called > siphash24_Nqwords. No. The bug is talking about "words" in the first place. Depending on your background, a "word" can be generally be either 16 bits or 32 bits (or, in some cases, 18 bits). In theory, a 64-bit entity can be a "word" too, but pretty much nobody uses that. Even architectures that started out with a 64-bit register size and never had any smaller historical baggage (eg alpha) tend to call 32-bit entities "words". So 16 bits can be a word, but some people/architectures will call it a "half-word". To make matters even more confusing, a "quadword" is generally always 64 bits, regardless of the size of "word". So please try to avoid the use of "word" entirely. It's too ambiguous, and it's not even helpful as a "size of the native register". It's almost purely random. For the kernel, we tend use - uX for types that have specific sizes (X being the number of bits) - "[unsigned] long" for native register size But never "word". Linus
Powered by blists - more mailing lists
Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.