libs:

	libaxolotl:
		updated libaxolotl (libsignal-c) from (https://github.com/WhisperSystems/libsignal-protocol-c)

1 files changed, 19 insertions, 0 deletions

diff --git a/libs/libaxolotl/src/curve25519/ed25519/additions/fe_montx_to_edy.c b/libs/libaxolotl/src/curve25519/ed25519/additions/fe_montx_to_edy.c
new file mode 100644
index 0000000000..b0f8c63276
--- /dev/null
+++ b/libs/libaxolotl/src/curve25519/ed25519/additions/fe_montx_to_edy.c
@@ -0,0 +1,19 @@
+
+#include "fe.h"
+#include "crypto_additions.h"
+
+void fe_montx_to_edy(fe y, const fe u)
+{
+  /* 
+     y = (u - 1) / (u + 1)
+
+     NOTE: u=-1 is converted to y=0 since fe_invert is mod-exp
+  */
+  fe one, um1, up1;
+
+  fe_1(one);
+  fe_sub(um1, u, one);
+  fe_add(up1, u, one);
+  fe_invert(up1, up1);
+  fe_mul(y, um1, up1);
+}