1 files changed, 44 insertions, 0 deletions
diff --git a/jni/ed25519/additions/compare.c b/jni/ed25519/additions/compare.c
new file mode 100644
index 00000000..8b1e3138
--- /dev/null
+++ b/jni/ed25519/additions/compare.c
@@ -0,0 +1,44 @@
+#include <string.h>
+#include "compare.h"
+
+/* Const-time comparison from SUPERCOP, but here it's only used for 
+   signature verification, so doesn't need to be const-time.  But
+   copied the nacl version anyways. */
+int crypto_verify_32_ref(const unsigned char *x, const unsigned char *y)
+{
+  unsigned int differentbits = 0;
+#define F(i) differentbits |= x[i] ^ y[i];
+  F(0)
+  F(1)
+  F(2)
+  F(3)
+  F(4)
+  F(5)
+  F(6)
+  F(7)
+  F(8)
+  F(9)
+  F(10)
+  F(11)
+  F(12)
+  F(13)
+  F(14)
+  F(15)
+  F(16)
+  F(17)
+  F(18)
+  F(19)
+  F(20)
+  F(21)
+  F(22)
+  F(23)
+  F(24)
+  F(25)
+  F(26)
+  F(27)
+  F(28)
+  F(29)
+  F(30)
+  F(31)
+  return (1 & ((differentbits - 1) >> 8)) - 1;
+}