+ }
+
+static int rsa_blinding_invert(BN_BLINDING *b, BIGNUM *f, BIGNUM *unblind,
+ BN_CTX *ctx)
+ {
+ /* For local blinding, unblind is set to NULL, and BN_BLINDING_invert_ex
+ * will use the unblinding factor stored in BN_BLINDING.
+ * If BN_BLINDING is shared between threads, unblind must be non-null:
+ * BN_BLINDING_invert_ex will then use the local unblinding factor,
+ * and will only read the modulus from BN_BLINDING.
+ * In both cases it's safe to access the blinding without a lock.
+ */
+ return BN_BLINDING_invert_ex(f, unblind, b, ctx);
+ }