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crypto: qce - simplify qce_xts_swapiv()

PATCH In review Thorsten Blum 3 participants 3 messages Mar 30 – Apr 12

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Thorsten Blum

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#0 lore raw

PATCH 1/1 crypto: qce - simplify qce_xts_swapiv()

Declare 'swap' as zero-initialized and use a single index variable to simplify the byte-swapping loop in qce_xts_swapiv(). Add a comment for clarity.

Signed-off-by Thorsten Blum <[email protected]>
---
 drivers/crypto/qce/common.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)
drivers/crypto/qce/common.c +6 -6
index 04253a8d3340..54a78a57f630 100644
@@ -280,17 +280,17 @@ static u32 qce_encr_cfg(unsigned long flags, u32 aes_key_size)
 #ifdef CONFIG_CRYPTO_DEV_QCE_SKCIPHER
 static void qce_xts_swapiv(__be32 *dst, const u8 *src, unsigned int ivsize)
 {
-	u8 swap[QCE_AES_IV_LENGTH];
-	u32 i, j;
+	u8 swap[QCE_AES_IV_LENGTH] = {0};
+	unsigned int i, offset;
 
 	if (ivsize > QCE_AES_IV_LENGTH)
 		return;
 
-	memset(swap, 0, QCE_AES_IV_LENGTH);
+	offset = QCE_AES_IV_LENGTH - ivsize;
 
-	for (i = (QCE_AES_IV_LENGTH - ivsize), j = ivsize - 1;
-	     i < QCE_AES_IV_LENGTH; i++, j--)
-		swap[i] = src[j];
+	/* Reverse and right-align IV bytes. */
+	for (i = 0; i < ivsize; i++)
+		swap[offset + i] = src[ivsize - 1 - i];
 
 	qce_cpu_to_be32p_array(dst, swap, QCE_AES_IV_LENGTH);
 }
Reviewed-by on v1 1/1
#1 lore raw
Quoted 5 lines · Thorsten Blum

Declare 'swap' as zero-initialized and use a single index variable to simplify the byte-swapping loop in qce_xts_swapiv(). Add a comment for clarity.

Signed-off-by Thorsten Blum <[email protected]>
Reviewed-by Bjorn Andersson <[email protected]>

Regards,
Bjorn

Quoted 33 lines
---
 drivers/crypto/qce/common.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)
drivers/crypto/qce/common.c +6 -6
index 04253a8d3340..54a78a57f630 100644
@@ -280,17 +280,17 @@ static u32 qce_encr_cfg(unsigned long flags, u32 aes_key_size)
 #ifdef CONFIG_CRYPTO_DEV_QCE_SKCIPHER
 static void qce_xts_swapiv(__be32 *dst, const u8 *src, unsigned int ivsize)
 {
-	u8 swap[QCE_AES_IV_LENGTH];
-	u32 i, j;
+	u8 swap[QCE_AES_IV_LENGTH] = {0};
+	unsigned int i, offset;
 
 	if (ivsize > QCE_AES_IV_LENGTH)
 		return;
 
-	memset(swap, 0, QCE_AES_IV_LENGTH);
+	offset = QCE_AES_IV_LENGTH - ivsize;
 
-	for (i = (QCE_AES_IV_LENGTH - ivsize), j = ivsize - 1;
-	     i < QCE_AES_IV_LENGTH; i++, j--)
-		swap[i] = src[j];
+	/* Reverse and right-align IV bytes. */
+	for (i = 0; i < ivsize; i++)
+		swap[offset + i] = src[ivsize - 1 - i];
 
 	qce_cpu_to_be32p_array(dst, swap, QCE_AES_IV_LENGTH);
 }
maintainer
#2 lore raw
In reply to Thorsten Blum
Quoted 8 lines · Thorsten Blum

Declare 'swap' as zero-initialized and use a single index variable to simplify the byte-swapping loop in qce_xts_swapiv(). Add a comment for clarity.

Signed-off-by Thorsten Blum <[email protected]>
---
 drivers/crypto/qce/common.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

Patch applied. Thanks.

Signature · 3 lines
Email: Herbert Xu <[email protected]>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt