[PATCH 2/2] Fixing vmx-crypto GHASH Key issue on little endian

From: Leonidas S Barbosa
Date: Fri Aug 14 2015 - 09:14:27 EST


GHASH table algorithm is using a big endian key.
In little endian machines key will be LE ordered.
After a lxvd2x instruction key is loaded as it is,
LE/BE order, in first case it'll generate a wrong
table resulting in wrong hashes from the algorithm.

Bug affects only LE machines.
In order to fix it we do a swap for loaded key.

Signed-off-by: Leonidas S Barbosa <leosilva@xxxxxxxxxxxxxxxxxx>
---
drivers/crypto/vmx/ghashp8-ppc.pl | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/drivers/crypto/vmx/ghashp8-ppc.pl b/drivers/crypto/vmx/ghashp8-ppc.pl
index 0a6f899..d8429cb 100644
--- a/drivers/crypto/vmx/ghashp8-ppc.pl
+++ b/drivers/crypto/vmx/ghashp8-ppc.pl
@@ -61,6 +61,12 @@ $code=<<___;
mtspr 256,r0
li r10,0x30
lvx_u $H,0,r4 # load H
+ le?xor r7,r7,r7
+ le?addi r7,r7,0x8 # need a vperm start with 08
+ le?lvsr 5,0,r7
+ le?vspltisb 6,0x0f
+ le?vxor 5,5,6 # set a b-endian mask
+ le?vperm $H,$H,$H,5

vspltisb $xC2,-16 # 0xf0
vspltisb $t0,1 # one
--
2.1.0

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