* #35924 (zrtp): switch to libzrtpcpp
diff --git a/jni/libzrtp/sources/bnlib/ec/ec.h b/jni/libzrtp/sources/bnlib/ec/ec.h
new file mode 100644
index 0000000..172ffd8
--- /dev/null
+++ b/jni/libzrtp/sources/bnlib/ec/ec.h
@@ -0,0 +1,272 @@
+/*
+ * 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 _EC_H_
+#define _EC_H_
+
+#include <bn.h>
+
+/**
+ * @file ec.h
+ * @brief Elliptic curve functions for bnlib
+ * @defgroup BNLIB_EC Elliptic curve functions
+ * @{
+ */
+
+#ifdef __cplusplus
+extern "C"
+{
+#endif
+
+typedef struct BigNum BigNum;
+
+typedef enum {
+    NIST192P = 1,
+    NIST224P = 2,
+    NIST256P = 3,
+    NIST384P = 4,
+    NIST521P = 5,
+    Curve25519 = 10,
+    Curve3617  = 11
+} Curves;
+
+/**
+ * \brief This structure contains the x, y affine coordinates and the z value if we
+ *        use projective coordinates during EC point arithmetic.
+ */
+typedef struct _EcPoint {
+    BigNum *x, *y, *z;
+    BigNum tx, ty, tz;
+} EcPoint;
+
+/**
+ * @brief This structure contains the value of EC curves over Prime Fields.
+ *
+ * The for NIST curves the field names correspond to the variable names defined in 
+ * NIST FIPS 186-3, E.1.2. The <b>a</b> curve parameter is the constant -3 and is 
+ * computed during initialization of the curve structure.
+ *
+ * For other curves, for example curve3917 we have less parameters to fill in, mostly
+ * the prime number, the base point, etc. Refer to the curve's initialization function
+ * about the use of the fileds.
+ */
+struct EcCurve;
+struct EcCurve {
+    Curves id;
+    BigNum _p;
+    BigNum _n;
+    BigNum _SEED;
+    BigNum _c;
+    BigNum _a;
+    BigNum _b;
+    BigNum _Gx;
+    BigNum _Gy;
+    /* Pointers to the BigNum structures, for better readability mainly */
+    BigNum *p;
+    BigNum *n;
+    BigNum *SEED;
+    BigNum *c;
+    BigNum *a;
+    BigNum *b;
+    BigNum *Gx;
+    BigNum *Gy;
+    /* some scratch pad variables, the EC algorithms use them to 
+       avoid to much memory allocation/deallocatio0n overhead */
+  BigNum _S1, _U1, _H, _R, _t0, _t1, _t2, _t3;
+  BigNum *S1, *U1, *H, *R, *t0, *t1, *t2, *t3;
+  int (*affineOp)(const struct EcCurve *curve, EcPoint *R, const EcPoint *P);
+  int (*doubleOp)(const struct EcCurve *curve, EcPoint *R, const EcPoint *P);
+  int (*addOp)(const struct EcCurve *curve, EcPoint *R, const EcPoint *P, const EcPoint *Q);
+  int (*modOp)(BigNum *, const BigNum *, const BigNum *);
+  int (*checkPubOp)(const struct EcCurve *curve, const EcPoint *pub);
+  int (*randomOp)(const struct EcCurve *curve, BigNum *d);
+  int (*mulScalar)(const struct EcCurve *curve, EcPoint *R, const EcPoint *P, const BigNum *scalar);
+
+};
+
+typedef struct EcCurve EcCurve;
+typedef EcCurve NistECpCurve;
+
+/**
+ * \brief          Marco to initialize a EC point structure.
+ *
+ * \param P        Address of the EC point structure
+ */
+#define INIT_EC_POINT(P) {EcPoint *e = P; e->x = &e->tx; e->y = &e->ty; e->z = &e->tz; bnBegin(e->x); bnBegin(e->y); bnBegin(e->z);}
+
+/**
+ * \brief          Marco to free a EC point structure.
+ *
+ * \param P        Address of the EC point structure
+ */
+#define FREE_EC_POINT(P) {EcPoint *e = P; bnEnd(e->x); bnEnd(e->y); bnEnd(e->z);}
+
+/**
+ * \brief          Marco to set a EC point structure to the curve's base point.
+ *
+ * \param C        Address of the NistECpCurve structure.
+ *
+ * \param P        Address of the EC point structure.
+ */
+#define SET_EC_BASE_POINT(C, P) {EcPoint *e = P;  const EcCurve *c = C; bnCopy(e->x, c->Gx); bnCopy(e->y, c->Gy); bnSetQ(e->z, 1);}
+
+/*
+ * EC point helper functions
+ */
+extern void ecInitPoint(EcPoint *P);
+
+extern void ecFreePoint(EcPoint *P);
+
+extern void ecSetBasePoint(EcCurve *C, EcPoint *P);
+
+/**
+ * \brief          Get NIST EC curve parameters.
+ *
+ *                 Before reusing a EC curve structure make sure to call ecFreeCurveNistECp
+ *                 to return memory.
+ *
+ * \param curveId  Which curve to initialize
+ *
+ * \param curve    Pointer to a EcCurve structure
+ *
+ * \return         0 if successful
+ *
+ * \note           Call ecFreeCurveNistECp to return allocated memory.
+ */
+int ecGetCurveNistECp(Curves curveId, NistECpCurve *curve);
+
+
+/**
+ * \brief          Free EC curve parameters.
+ *
+ * \param curve    Pointer to a EcCurve structure
+ *
+ * \note           Curve parameters must be initialized calling ecGetCurveNistECp.
+ */
+void ecFreeCurveNistECp(EcCurve *curve);
+
+/**
+ * \brief          Double an EC point.
+ *
+ *                 This function uses affine coordinates to perform the computations. For
+ *                 further reference see RFC 6090 or the standard work <i>Guide to Elliptic
+ *                 Curve Cryptography</i>.
+ *
+ * \param          curve  Address of EC curve structure
+ * \param          R      Address of resulting EC point structure
+ * \param          P      Address of the EC point structure
+ *
+ * \return         0 if successful
+ */
+int ecDoublePoint(const EcCurve *curve, EcPoint *R, const EcPoint *P);
+
+/**
+ * \brief          Add two EC points.
+ *
+ *                 This function uses affine coordinates to perform the computations. For
+ *                 further reference see RFC 6090 or the standard work <i>Guide to Elliptic
+ *                 Curve Cryptography</i>.
+ *
+ * \param          curve  Address of EC curve structure
+ * \param          R      Address of resulting EC point structure
+ * \param          P      Address of the first EC point structure
+ * \param          Q      Address of the second EC point structure
+ *
+ * \return         0 if successful
+ */
+int ecAddPoint(const EcCurve *curve, EcPoint *R, const EcPoint *P, const EcPoint *Q);
+
+/**
+ * \brief          Mulitply an EC point with a scalar value.
+ *
+ * \param          curve  Address of EC curve structure
+ * \param          R      Address of resulting EC point structure
+ * \param          P      Address of the EC point structure
+ * \param          scalar Address of the scalar multi-precision integer value
+ *
+ * \return         0 if successful
+ */
+int ecMulPointScalar(const EcCurve *curve, EcPoint *R, const EcPoint *P, const BigNum *scalar);
+
+/**
+ * \brief          Convert an EC point from Jacobian projective coordinates to normal affine x/y coordinates.
+ *
+ * \param          curve  Address of EC curve structure
+ * \param          R      Address of EC point structure that receives the x/y coordinates
+ * \param          P      Address of the EC point structure that contains the jacobian x/y/z coordinates.
+ *
+ * \return         0 if successful
+ */
+int ecGetAffine(const EcCurve *curve, EcPoint *R, const EcPoint *P);
+
+/**
+ * @brief Generate a random number.
+ *
+ * The method generates a random number and checks if it matches the curve restricitions.
+ * Use this number as ECDH private key.
+ *
+ * @param curve the NIST curve to use.
+ *
+ * @param d receives the generated random number.
+ */
+int ecGenerateRandomNumber(const NistECpCurve *curve, BigNum *d);
+
+/**
+ * @brief Check a public key.
+ *
+ * The method checks if a public key is valid. For NIST curves it uses the
+ * ECC Partial Validation, NIST SP800-56A section 5.6.2.6
+ * 
+ * For other curves it computes the equation and compares the left hand and 
+ * the right handresults. If they are equal the point is on the curve.
+ *
+ * @param curve the curve to use.
+ *
+ * @param pub the public key to check.
+ *
+ * @returns true (!0) if the check was ok, false (0) otherwise.
+ *
+ * @note The function uses some scratch pad variable of the NistECpCurve structure.
+ */
+int ecCheckPubKey(const EcCurve *curve, const EcPoint *pub);
+
+int ecGetCurvesCurve(Curves curveId, EcCurve *curve);
+
+void ecFreeCurvesCurve(EcCurve *curve);
+
+/**
+ * This is a special function for DJB's curve 25519. Actually it's the scalar multiplication
+ * mypublic = basepoint * secret
+ */
+int curve25519_donna(unsigned char *mypublic, const unsigned char *secret, const unsigned char *basepoint);
+
+/*
+ * Some additional functions that are not available in bnlib
+ */
+int bnAddMod_ (struct BigNum *rslt, struct BigNum *n1, struct BigNum *mod);
+
+int bnAddQMod_ (struct BigNum *rslt, unsigned n1, struct BigNum *mod);
+
+int bnSubMod_ (struct BigNum *rslt, struct BigNum *n1, struct BigNum *mod);
+
+int bnSubQMod_ (struct BigNum *rslt, unsigned n1, struct BigNum *mod);
+
+int bnMulMod_ (struct BigNum *rslt, struct BigNum *n1, struct BigNum *n2, struct BigNum *mod, const EcCurve *curve);
+
+int bnMulQMod_ (struct BigNum *rslt, struct BigNum *n1, unsigned n2, struct BigNum *mod, const EcCurve *curve);
+
+int bnSquareMod_ (struct BigNum *rslt, struct BigNum *n1, struct BigNum *mod, const EcCurve *curve);
+
+#ifdef __cplusplus
+}
+#endif
+
+/**
+ * @}
+ */
+
+#endif