[PATCH v2 4/6] crypto/openssl: fix 3DES-CTR with big endian CPUs

[David Marchand <david.marchand@redhat.com>]

Caught by code review.

Don't byte swap unconditionally (assuming that CPU is little endian is
wrong). Instead, convert from big endian to cpu and vice versa.

Besides, avoid unaligned accesses and remove the ctr_inc helper that is
not used anywhere else.

Fixes: d61f70b4c918 ("crypto/libcrypto: add driver for OpenSSL library")
Cc: stable@dpdk.org

Signed-off-by: David Marchand <david.marchand@redhat.com>
Acked-by: Morten Brørup <mb@smartsharesystems.com>
---
Changes since v1:
- fixed unaligned access,
- removed unneeded helper,

---
 drivers/crypto/openssl/rte_openssl_pmd.c | 28 ++++++++----------------
 1 file changed, 9 insertions(+), 19 deletions(-)

diff --git a/drivers/crypto/openssl/rte_openssl_pmd.c b/drivers/crypto/openssl/rte_openssl_pmd.c
index 9657b70c7a..0616383921 100644
--- a/drivers/crypto/openssl/rte_openssl_pmd.c
+++ b/drivers/crypto/openssl/rte_openssl_pmd.c
@@ -2,6 +2,7 @@
  * Copyright(c) 2016-2017 Intel Corporation
  */
 
+#include <rte_byteorder.h>
 #include <rte_common.h>
 #include <rte_hexdump.h>
 #include <rte_cryptodev.h>
@@ -99,22 +100,6 @@ digest_name_get(enum rte_crypto_auth_algorithm algo)
 
 static int cryptodev_openssl_remove(struct rte_vdev_device *vdev);
 
-/*----------------------------------------------------------------------------*/
-
-/**
- * Increment counter by 1
- * Counter is 64 bit array, big-endian
- */
-static void
-ctr_inc(uint8_t *ctr)
-{
-	uint64_t *ctr64 = (uint64_t *)ctr;
-
-	*ctr64 = __builtin_bswap64(*ctr64);
-	(*ctr64)++;
-	*ctr64 = __builtin_bswap64(*ctr64);
-}
-
 /*
  *------------------------------------------------------------------------------
  * Session Prepare
@@ -1192,7 +1177,8 @@ static int
 process_openssl_cipher_des3ctr(struct rte_mbuf *mbuf_src, uint8_t *dst,
 		int offset, uint8_t *iv, int srclen, EVP_CIPHER_CTX *ctx)
 {
-	uint8_t ebuf[8], ctr[8];
+	uint8_t ebuf[8];
+	uint64_t ctr;
 	int unused, n;
 	struct rte_mbuf *m;
 	uint8_t *src;
@@ -1208,15 +1194,19 @@ process_openssl_cipher_des3ctr(struct rte_mbuf *mbuf_src, uint8_t *dst,
 	src = rte_pktmbuf_mtod_offset(m, uint8_t *, offset);
 	l = rte_pktmbuf_data_len(m) - offset;
 
-	memcpy(ctr, iv, 8);
+	memcpy(&ctr, iv, 8);
 
 	for (n = 0; n < srclen; n++) {
 		if (n % 8 == 0) {
+			uint64_t cpu_ctr;
+
 			if (EVP_EncryptUpdate(ctx,
 					(unsigned char *)&ebuf, &unused,
 					(const unsigned char *)&ctr, 8) <= 0)
 				goto process_cipher_des3ctr_err;
-			ctr_inc(ctr);
+			cpu_ctr = rte_be_to_cpu_64(ctr);
+			cpu_ctr++;
+			ctr = rte_cpu_to_be_64(cpu_ctr);
 		}
 		dst[n] = *(src++) ^ ebuf[n % 8];
 
-- 
2.46.2