xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

crypto: gf128mul - fix some comments

Browse Source 
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 <alexcope@google.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Eric Biggers
2017-02-14 13:43:27 -08:00
committed by Herbert Xu
parent 28b62b1458
commit 63be5b53b6
2 changed files with 21 additions and 18 deletions
Download Patch File Download Diff File Expand all files Collapse all files

13
crypto/gf128mul.c
View File

@@ -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