* #35924 (zrtp): switch to libzrtpcpp
diff --git a/jni/libzrtp/sources/bnlib/ec/ecdh.h b/jni/libzrtp/sources/bnlib/ec/ecdh.h
new file mode 100644
index 0000000..7ec32ad
--- /dev/null
+++ b/jni/libzrtp/sources/bnlib/ec/ecdh.h
@@ -0,0 +1,61 @@
+/*
+ * Copyright (C) 2012 Werner Dittmann
+ * All rights reserved. For licensing and other legal details, see the file legal.c.
+ *
+ * @author Werner Dittmann <Werner.Dittmann@t-online.de>
+ *
+ */
+#ifndef _ECDH_H_
+#define _ECDH_H_
+/**
+ * @file ec.h
+ * @brief Elliptic Diffie-Hellman functions for bnlib
+ * @defgroup BNLIB_EC Elliptic curve functions
+ * @{
+ */
+
+#ifdef __cplusplus
+extern "C"
+{
+#endif
+
+/**
+ * @brief Takes a secret large random number and computes the public EC point.
+ *
+ * @param curve is the curve to use.
+ *
+ * @param Q the functions writes the computed public point in this parameter.
+ *
+ * @param d is the secret random number.
+ *
+ * @return @c true (!0) if public key was computed, @c false otherwise.
+ *
+ * @sa ecGenerateRandomNumber
+ */
+int ecdhGeneratePublic(const EcCurve *curve, EcPoint *Q, const BigNum *d);
+
+/**
+ * @brief Computes the key agreement value.
+ *
+ * Takes the public EC point of the other party and applies the EC DH algorithm
+ * to compute the agreed value.
+ *
+ * @param curve is the curve to use, must be the same curve as used in
+ * @c ecdhGeneratePublic.
+ *
+ * @param agreemtn the functions writes the computed agreed value in this parameter.
+ *
+ * @param Q is the other party's public point.
+ *
+ * @param d is the secret random number.
+ */
+int ecdhComputeAgreement(const EcCurve *curve, BigNum *agreement, const EcPoint *Q, const BigNum *d);
+
+#ifdef __cplusplus
+}
+#endif
+/**
+ * @}
+ */
+
+#endif
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