[PATCH 5.12 207/677] crypto: arm/blake2s - fix for big endian

From: Greg Kroah-Hartman
Date: Wed May 12 2021 - 14:31:49 EST


From: Eric Biggers <ebiggers@xxxxxxxxxx>

[ Upstream commit d2f2516a3882c0c6463e33c9b112b39bd483f821 ]

The new ARM BLAKE2s code doesn't work correctly (fails the self-tests)
in big endian kernel builds because it doesn't swap the endianness of
the message words when loading them. Fix this.

Fixes: 5172d322d34c ("crypto: arm/blake2s - add ARM scalar optimized BLAKE2s")
Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>
Acked-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/arm/crypto/blake2s-core.S | 21 +++++++++++++++++++++
1 file changed, 21 insertions(+)

diff --git a/arch/arm/crypto/blake2s-core.S b/arch/arm/crypto/blake2s-core.S
index bed897e9a181..86345751bbf3 100644
--- a/arch/arm/crypto/blake2s-core.S
+++ b/arch/arm/crypto/blake2s-core.S
@@ -8,6 +8,7 @@
*/

#include <linux/linkage.h>
+#include <asm/assembler.h>

// Registers used to hold message words temporarily. There aren't
// enough ARM registers to hold the whole message block, so we have to
@@ -38,6 +39,23 @@
#endif
.endm

+.macro _le32_bswap a, tmp
+#ifdef __ARMEB__
+ rev_l \a, \tmp
+#endif
+.endm
+
+.macro _le32_bswap_8x a, b, c, d, e, f, g, h, tmp
+ _le32_bswap \a, \tmp
+ _le32_bswap \b, \tmp
+ _le32_bswap \c, \tmp
+ _le32_bswap \d, \tmp
+ _le32_bswap \e, \tmp
+ _le32_bswap \f, \tmp
+ _le32_bswap \g, \tmp
+ _le32_bswap \h, \tmp
+.endm
+
// Execute a quarter-round of BLAKE2s by mixing two columns or two diagonals.
// (a0, b0, c0, d0) and (a1, b1, c1, d1) give the registers containing the two
// columns/diagonals. s0-s1 are the word offsets to the message words the first
@@ -180,8 +198,10 @@ ENTRY(blake2s_compress_arch)
tst r1, #3
bne .Lcopy_block_misaligned
ldmia r1!, {r2-r9}
+ _le32_bswap_8x r2, r3, r4, r5, r6, r7, r8, r9, r14
stmia r12!, {r2-r9}
ldmia r1!, {r2-r9}
+ _le32_bswap_8x r2, r3, r4, r5, r6, r7, r8, r9, r14
stmia r12, {r2-r9}
.Lcopy_block_done:
str r1, [sp, #68] // Update message pointer
@@ -268,6 +288,7 @@ ENTRY(blake2s_compress_arch)
1:
#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
ldr r3, [r1], #4
+ _le32_bswap r3, r4
#else
ldrb r3, [r1, #0]
ldrb r4, [r1, #1]
--
2.30.2