diff --git a/wolfcrypt/src/fe_low_mem.c b/wolfcrypt/src/fe_low_mem.c
index 13c88cbb4..b42cdfdfd 100644
--- a/wolfcrypt/src/fe_low_mem.c
+++ b/wolfcrypt/src/fe_low_mem.c
@@ -141,7 +141,7 @@ static void xc_diffadd(byte *x5, byte *z5,
 }
 
 #ifndef FREESCALE_LTC_ECC
-int curve25519(byte *result, byte *e, byte *q)
+int curve25519(byte *result, const byte *e, const byte *q)
 {
 	/* Current point: P_m */
 	byte xm[F25519_SIZE];
diff --git a/wolfcrypt/src/fe_x25519_128.i b/wolfcrypt/src/fe_x25519_128.i
index 10e43d9cd..a20fcf79a 100644
--- a/wolfcrypt/src/fe_x25519_128.i
+++ b/wolfcrypt/src/fe_x25519_128.i
@@ -406,7 +406,7 @@ void fe_invert(fe r, const fe a)
  * n  The scalar as an array of bytes.
  * a  A field element as an array of bytes.
  */
-int curve25519(byte* r, byte* n, byte* a)
+int curve25519(byte* r, const byte* n, const byte* a)
 {
     fe           x1, x2, z2, x3, z3;
     fe           t0, t1;
diff --git a/wolfcrypt/src/port/arm/armv8-32-curve25519.c b/wolfcrypt/src/port/arm/armv8-32-curve25519.c
index 3cc843929..c2c73f3c3 100644
--- a/wolfcrypt/src/port/arm/armv8-32-curve25519.c
+++ b/wolfcrypt/src/port/arm/armv8-32-curve25519.c
@@ -2910,7 +2910,7 @@ void fe_invert(fe r, const fe a)
     );
 }
 
-int curve25519(byte* r, byte* n, byte* a)
+int curve25519(byte* r, const byte* n, const byte* a)
 {
     __asm__ __volatile__ (
         "sub	sp, sp, #0xbc\n\t"
diff --git a/wolfcrypt/src/port/arm/armv8-curve25519.c b/wolfcrypt/src/port/arm/armv8-curve25519.c
index 97d30025f..a72ae8fbd 100644
--- a/wolfcrypt/src/port/arm/armv8-curve25519.c
+++ b/wolfcrypt/src/port/arm/armv8-curve25519.c
@@ -1007,7 +1007,7 @@ void fe_invert(fe r, const fe a)
     );
 }
 
-int curve25519(byte* r, byte* n, byte* a)
+int curve25519(byte* r, const byte* n, const byte* a)
 {
     __asm__ __volatile__ (
         "stp	x29, x30, [sp, #-192]!\n\t"
diff --git a/wolfcrypt/src/port/nxp/ksdk_port.c b/wolfcrypt/src/port/nxp/ksdk_port.c
index fdbd95764..7b550f794 100644
--- a/wolfcrypt/src/port/nxp/ksdk_port.c
+++ b/wolfcrypt/src/port/nxp/ksdk_port.c
@@ -1122,7 +1122,7 @@ status_t LTC_PKHA_Curve25519ComputeY(ltc_pkha_ecc_point_t *ltcPoint)
 /* if type is set, the input point p is in Montgomery curve coordinates,
     so there is a map to Weierstrass curve */
 /* q output point is always in Montgomery curve coordinates */
-int nxp_ltc_curve25519(ECPoint *q, byte *n, const ECPoint *p, fsl_ltc_ecc_coordinate_system_t type)
+int nxp_ltc_curve25519(ECPoint *q, const byte *n, const ECPoint *p, fsl_ltc_ecc_coordinate_system_t type)
 {
     status_t status;
     ltc_pkha_ecc_point_t ltcPoint;
diff --git a/wolfssl/wolfcrypt/port/nxp/ksdk_port.h b/wolfssl/wolfcrypt/port/nxp/ksdk_port.h
index 9c52bedaf..f73579c2a 100644
--- a/wolfssl/wolfcrypt/port/nxp/ksdk_port.h
+++ b/wolfssl/wolfcrypt/port/nxp/ksdk_port.h
@@ -65,7 +65,7 @@ int ksdk_port_init(void);
 	int wc_ecc_point_add(ecc_point *mG, ecc_point *mQ, ecc_point *mR, mp_int *m);
 
 	#ifdef HAVE_CURVE25519
-		int nxp_ltc_curve25519(ECPoint *q, byte *n, const ECPoint *p, fsl_ltc_ecc_coordinate_system_t type);
+		int nxp_ltc_curve25519(ECPoint *q, const byte *n, const ECPoint *p, fsl_ltc_ecc_coordinate_system_t type);
 		const ECPoint *nxp_ltc_curve25519_GetBasePoint(void);
 		status_t LTC_PKHA_Curve25519ToWeierstrass(const ltc_pkha_ecc_point_t *ltcPointIn, ltc_pkha_ecc_point_t *ltcPointOut);
 		status_t LTC_PKHA_WeierstrassToCurve25519(const ltc_pkha_ecc_point_t *ltcPointIn, ltc_pkha_ecc_point_t *ltcPointOut);