Simplify constant-time RSA padding check.
(Imported form upstream's 455b65dfab0de51c9f67b3c909311770f2b3f801 and
0d6a11a91f4de238ce533c40bd9507fe5d95f288)
Change-Id: Ia195c7fe753cfa3a7f8c91d2d7b2cd40a547be43
diff --git a/crypto/internal.h b/crypto/internal.h
index f32d369..e32f460 100644
--- a/crypto/internal.h
+++ b/crypto/internal.h
@@ -225,11 +225,22 @@
return constant_time_is_zero(a ^ b);
}
-/* constant_time_eq_8 acts like constant_time_eq but returns an 8-bit mask. */
+/* constant_time_eq_8 acts like |constant_time_eq| but returns an 8-bit mask. */
static inline uint8_t constant_time_eq_8(unsigned int a, unsigned int b) {
return (uint8_t)(constant_time_eq(a, b));
}
+/* constant_time_eq_int acts like |constant_time_eq| but works on int values. */
+static inline unsigned int constant_time_eq_int(int a, int b) {
+ return constant_time_eq((unsigned)(a), (unsigned)(b));
+}
+
+/* constant_time_eq_int_8 acts like |constant_time_eq_int| but returns an 8-bit
+ * mask. */
+static inline uint8_t constant_time_eq_int_8(int a, int b) {
+ return constant_time_eq_8((unsigned)(a), (unsigned)(b));
+}
+
/* constant_time_select returns (mask & a) | (~mask & b). When |mask| is all 1s
* or all 0s (as returned by the methods above), the select methods return
* either |a| (if |mask| is nonzero) or |b| (if |mask| is zero). */
