diff --git a/library/chacha20.c b/library/chacha20.c
index 658f046..f6d6e25 100644
--- a/library/chacha20.c
+++ b/library/chacha20.c
@@ -48,12 +48,6 @@
 #define inline __inline
 #endif
 
-/* Parameter validation macros */
-#define CHACHA20_VALIDATE_RET( cond )                                       \
-    MBEDTLS_INTERNAL_VALIDATE_RET( cond, MBEDTLS_ERR_CHACHA20_BAD_INPUT_DATA )
-#define CHACHA20_VALIDATE( cond )                                           \
-    MBEDTLS_INTERNAL_VALIDATE( cond )
-
 #define ROTL32( value, amount ) \
     ( (uint32_t) ( (value) << (amount) ) | ( (value) >> ( 32 - (amount) ) ) )
 
@@ -172,8 +166,6 @@
 
 void mbedtls_chacha20_init( mbedtls_chacha20_context *ctx )
 {
-    CHACHA20_VALIDATE( ctx != NULL );
-
     mbedtls_platform_zeroize( ctx->state, sizeof( ctx->state ) );
     mbedtls_platform_zeroize( ctx->keystream8, sizeof( ctx->keystream8 ) );
 
@@ -192,9 +184,6 @@
 int mbedtls_chacha20_setkey( mbedtls_chacha20_context *ctx,
                             const unsigned char key[32] )
 {
-    CHACHA20_VALIDATE_RET( ctx != NULL );
-    CHACHA20_VALIDATE_RET( key != NULL );
-
     /* ChaCha20 constants - the string "expand 32-byte k" */
     ctx->state[0] = 0x61707865;
     ctx->state[1] = 0x3320646e;
@@ -218,9 +207,6 @@
                              const unsigned char nonce[12],
                              uint32_t counter )
 {
-    CHACHA20_VALIDATE_RET( ctx != NULL );
-    CHACHA20_VALIDATE_RET( nonce != NULL );
-
     /* Counter */
     ctx->state[12] = counter;
 
@@ -245,10 +231,6 @@
     size_t offset = 0U;
     size_t i;
 
-    CHACHA20_VALIDATE_RET( ctx != NULL );
-    CHACHA20_VALIDATE_RET( size == 0 || input  != NULL );
-    CHACHA20_VALIDATE_RET( size == 0 || output != NULL );
-
     /* Use leftover keystream bytes, if available */
     while( size > 0U && ctx->keystream_bytes_used < CHACHA20_BLOCK_SIZE_BYTES )
     {
@@ -312,11 +294,6 @@
     mbedtls_chacha20_context ctx;
     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
 
-    CHACHA20_VALIDATE_RET( key != NULL );
-    CHACHA20_VALIDATE_RET( nonce != NULL );
-    CHACHA20_VALIDATE_RET( data_len == 0 || input  != NULL );
-    CHACHA20_VALIDATE_RET( data_len == 0 || output != NULL );
-
     mbedtls_chacha20_init( &ctx );
 
     ret = mbedtls_chacha20_setkey( &ctx, key );