qemu-ppc
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[Qemu-ppc] [PATCH] target-ppc: simplify AES emulation


From: Aurelien Jarno
Subject: [Qemu-ppc] [PATCH] target-ppc: simplify AES emulation
Date: Mon, 27 Oct 2014 17:25:52 +0100

This patch simplifies the AES code, by directly accessing the newly added
S-Box, InvS-Box tables instead of recreating them by using the AES_Te and
AES_Td tables.

Cc: Alexander Graf <address@hidden>
Cc: Paolo Bonzini <address@hidden>
Signed-off-by: Aurelien Jarno <address@hidden>
---
 target-ppc/int_helper.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Note: This has been requested by Paolo Bonzini, but I have no way to
test it, so it is only compile tested.

diff --git a/target-ppc/int_helper.c b/target-ppc/int_helper.c
index 713d777..e67a5ee 100644
--- a/target-ppc/int_helper.c
+++ b/target-ppc/int_helper.c
@@ -2352,7 +2352,7 @@ void helper_vcipherlast(ppc_avr_t *r, ppc_avr_t *a, 
ppc_avr_t *b)
     int i;
 
     VECTOR_FOR_INORDER_I(i, u8) {
-        r->AVRB(i) = b->AVRB(i) ^ (AES_Te4[a->AVRB(AES_shifts[i])] & 0xFF);
+        r->AVRB(i) = b->AVRB(i) ^ (AES_sbox[a->AVRB(AES_shifts[i])]);
     }
 }
 
@@ -2381,7 +2381,7 @@ void helper_vncipherlast(ppc_avr_t *r, ppc_avr_t *a, 
ppc_avr_t *b)
     int i;
 
     VECTOR_FOR_INORDER_I(i, u8) {
-        r->AVRB(i) = b->AVRB(i) ^ (AES_Td4[a->AVRB(AES_ishifts[i])] & 0xFF);
+        r->AVRB(i) = b->AVRB(i) ^ (AES_isbox[a->AVRB(AES_ishifts[i])]);
     }
 }
 
-- 
2.1.1




reply via email to

[Prev in Thread] Current Thread [Next in Thread]