fix for windows

aws · Jul 9, 2024 · 46dd057 · 46dd057
1 parent e1fc1a7
commit 46dd057
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Showing 2 changed files with 20 additions and 7 deletions.
diff --git a/crypto/fipsmodule/ec/ec_nistp.c b/crypto/fipsmodule/ec/ec_nistp.c
@@ -368,12 +368,10 @@ static void select_point_from_table(const ec_nistp_meth *ctx,
                                     ec_nistp_felem_limb *xyz_out,
                                     const ec_nistp_felem_limb *table,
                                     const size_t idx) {
-  size_t entry_size = 3 * ctx->felem_num_limbs *
-      (sizeof(ec_nistp_felem_limb)/sizeof(crypto_word_t));
+  size_t entry_size = 3 * ctx->felem_num_limbs * sizeof(ec_nistp_felem_limb);
 
-  constant_time_select_entry_from_table_w(
-          (crypto_word_t*)xyz_out,
-          (crypto_word_t*)table,
+  constant_time_select_entry_from_table_8(
+          (uint8_t*)xyz_out, (uint8_t*)table,
           idx, SCALAR_MUL_TABLE_NUM_POINTS, entry_size);
 }
 

diff --git a/crypto/internal.h b/crypto/internal.h
@@ -466,17 +466,32 @@ static inline void constant_time_select_array_w(
   }
 }
 
+static inline void constant_time_select_array_8(
+        uint8_t *c, uint8_t *a, uint8_t *b, uint8_t mask, size_t len) {
+  for (size_t i = 0; i < len; i++) {
+    c[i] = constant_time_select_8(mask, a[i], b[i]);
+  }
+}
+
 // constant_time_select_entry_from_table_w selects the idx-th entry from table.
 static inline void constant_time_select_entry_from_table_w(
         crypto_word_t *out, crypto_word_t *table,
-        size_t idx, size_t num_entries, size_t entry_size)
-{
+        size_t idx, size_t num_entries, size_t entry_size) {
   for (size_t i = 0; i < num_entries; i++) {
     crypto_word_t mask = constant_time_eq_w(i, idx);
     constant_time_select_array_w(out, &table[i * entry_size], out, mask, entry_size);
   }
 }
 
+static inline void constant_time_select_entry_from_table_8(
+        uint8_t *out, uint8_t *table, size_t idx,
+        size_t num_entries, size_t entry_size) {
+  for (size_t i = 0; i < num_entries; i++) {
+    uint8_t mask = (uint8_t)(constant_time_eq_w(i, idx));
+    constant_time_select_array_8(out, &table[i * entry_size], out, mask, entry_size);
+  }
+}
+
 #if defined(BORINGSSL_CONSTANT_TIME_VALIDATION)
 
 // CONSTTIME_SECRET takes a pointer and a number of bytes and marks that region