From 63be5b53b6d15f7706ad21e9801dae5b723e8340 Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Tue, 14 Feb 2017 13:43:27 -0800 Subject: crypto: gf128mul - fix some comments Fix incorrect references to GF(128) instead of GF(2^128), as these are two entirely different fields, and fix a few other incorrect comments. Cc: Alex Cope Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu --- crypto/gf128mul.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) (limited to 'crypto') diff --git a/crypto/gf128mul.c b/crypto/gf128mul.c index 72015fe..d9e3eec 100644 --- a/crypto/gf128mul.c +++ b/crypto/gf128mul.c @@ -44,7 +44,7 @@ --------------------------------------------------------------------------- Issue 31/01/2006 - This file provides fast multiplication in GF(128) as required by several + This file provides fast multiplication in GF(2^128) as required by several cryptographic authentication modes */ @@ -116,9 +116,10 @@ static const u16 gf128mul_table_lle[256] = gf128mul_dat(xda_lle); static const u16 gf128mul_table_bbe[256] = gf128mul_dat(xda_bbe); -/* These functions multiply a field element by x, by x^4 and by x^8 - * in the polynomial field representation. It uses 32-bit word operations - * to gain speed but compensates for machine endianess and hence works +/* + * The following functions multiply a field element by x or by x^8 in + * the polynomial field representation. They use 64-bit word operations + * to gain speed but compensate for machine endianness and hence work * correctly on both styles of machine. */ @@ -251,7 +252,7 @@ EXPORT_SYMBOL(gf128mul_bbe); /* This version uses 64k bytes of table space. A 16 byte buffer has to be multiplied by a 16 byte key - value in GF(128). If we consider a GF(128) value in + value in GF(2^128). If we consider a GF(2^128) value in the buffer's lowest byte, we can construct a table of the 256 16 byte values that result from the 256 values of this byte. This requires 4096 bytes. But we also @@ -330,7 +331,7 @@ EXPORT_SYMBOL(gf128mul_64k_bbe); /* This version uses 4k bytes of table space. A 16 byte buffer has to be multiplied by a 16 byte key - value in GF(128). If we consider a GF(128) value in a + value in GF(2^128). If we consider a GF(2^128) value in a single byte, we can construct a table of the 256 16 byte values that result from the 256 values of this byte. This requires 4096 bytes. If we take the highest byte in -- cgit v1.1