crypto/ec/ecp_nistz256.c: use OPENSSL_aligned_alloc_array

Allocate table in ecp_nistz256_windowed_mul() and preComputedTable
in ecp_nistz256_mult_precompute() using OPENSSL_aligned_alloc_array() call
instead of OPENSSL_malloc with a 64-byte slack and manual pointer alignment
adjustement.

Signed-off-by: Eugene Syromiatnikov <esyr@openssl.org>
Reviewed-by: Neil Horman <nhorman@openssl.org>
Reviewed-by: Saša Nedvědický <sashan@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/28295)

diff --git a/crypto/ec/ecp_nistz256.c b/crypto/ec/ecp_nistz256.c
index fb569091875696979f2e80ffc375c37c0cd3f145..f90c0122778ebad5187aa1bef9820a7ee23087e6 100644 (file)
--- a/crypto/ec/ecp_nistz256.c
+++ b/crypto/ec/ecp_nistz256.c
@@ -37,7 +37,6 @@
 # define TOBN(hi,lo)    ((BN_ULONG)hi<<32|lo)
 #endif
 
-#define ALIGNPTR(p,N)   ((unsigned char *)p+N-(size_t)p%N)
 #define P256_LIMBS      (256/BN_BITS2)
 
 typedef unsigned short u16;
@@ -623,13 +622,13 @@ __owur static int ecp_nistz256_windowed_mul(const EC_GROUP *group,
     void *table_storage = NULL;
 
     if ((num * 16 + 6) > OPENSSL_MALLOC_MAX_NELEMS(P256_POINT)
-        || (table_storage =
-            OPENSSL_malloc((num * 16 + 5) * sizeof(P256_POINT) + 64)) == NULL
+        || (table =
+            OPENSSL_aligned_alloc_array(num * 16 + 5, sizeof(P256_POINT), 64,
+                                        &table_storage)) == NULL
         || (p_str = OPENSSL_malloc_array(num, 33)) == NULL
         || (scalars = OPENSSL_malloc_array(num, sizeof(BIGNUM *))) == NULL)
         goto err;
 
-    table = (void *)ALIGNPTR(table_storage, 64);
     temp = (P256_POINT *)(table + num);
 
     for (i = 0; i < num; i++) {
@@ -815,7 +814,7 @@ __owur static int ecp_nistz256_mult_precompute(EC_GROUP *group, BN_CTX *ctx)
     size_t w;
 
     PRECOMP256_ROW *preComputedTable = NULL;
-    unsigned char *precomp_storage = NULL;
+    void *precomp_storage = NULL;
 
     /* if there is an old NISTZ256_PRE_COMP object, throw it away */
     EC_pre_comp_free(group);
@@ -855,12 +854,11 @@ __owur static int ecp_nistz256_mult_precompute(EC_GROUP *group, BN_CTX *ctx)
 
     w = 7;
 
-    if ((precomp_storage =
-         OPENSSL_malloc(37 * 64 * sizeof(P256_POINT_AFFINE) + 64)) == NULL)
+    if ((preComputedTable =
+         OPENSSL_aligned_alloc_array(37 * 64, sizeof(P256_POINT_AFFINE), 64,
+                                     &precomp_storage)) == NULL)
         goto err;
 
-    preComputedTable = (void *)ALIGNPTR(precomp_storage, 64);
-
     P = EC_POINT_new(group);
     T = EC_POINT_new(group);
     if (P == NULL || T == NULL)