diff --git a/library/aes.c b/library/aes.c
index ca94e0a..9ad12a6 100644
--- a/library/aes.c
+++ b/library/aes.c
@@ -489,8 +489,6 @@
 
 void mbedtls_aes_init( mbedtls_aes_context *ctx )
 {
-    AES_VALIDATE( ctx != NULL );
-
     memset( ctx, 0, sizeof( mbedtls_aes_context ) );
 }
 
@@ -505,8 +503,6 @@
 #if defined(MBEDTLS_CIPHER_MODE_XTS)
 void mbedtls_aes_xts_init( mbedtls_aes_xts_context *ctx )
 {
-    AES_VALIDATE( ctx != NULL );
-
     mbedtls_aes_init( &ctx->crypt );
     mbedtls_aes_init( &ctx->tweak );
 }
@@ -531,9 +527,6 @@
     unsigned int i;
     uint32_t *RK;
 
-    AES_VALIDATE_RET( ctx != NULL );
-    AES_VALIDATE_RET( key != NULL );
-
     switch( keybits )
     {
         case 128: ctx->nr = 10; break;
@@ -649,9 +642,6 @@
     uint32_t *RK;
     uint32_t *SK;
 
-    AES_VALIDATE_RET( ctx != NULL );
-    AES_VALIDATE_RET( key != NULL );
-
     mbedtls_aes_init( &cty );
 
     ctx->rk_offset = 0;
@@ -743,9 +733,6 @@
     const unsigned char *key1, *key2;
     unsigned int key1bits, key2bits;
 
-    AES_VALIDATE_RET( ctx != NULL );
-    AES_VALIDATE_RET( key != NULL );
-
     ret = mbedtls_aes_xts_decode_keys( key, keybits, &key1, &key1bits,
                                        &key2, &key2bits );
     if( ret != 0 )
@@ -768,9 +755,6 @@
     const unsigned char *key1, *key2;
     unsigned int key1bits, key2bits;
 
-    AES_VALIDATE_RET( ctx != NULL );
-    AES_VALIDATE_RET( key != NULL );
-
     ret = mbedtls_aes_xts_decode_keys( key, keybits, &key1, &key1bits,
                                        &key2, &key2bits );
     if( ret != 0 )
@@ -970,9 +954,6 @@
                            const unsigned char input[16],
                            unsigned char output[16] )
 {
-    AES_VALIDATE_RET( ctx != NULL );
-    AES_VALIDATE_RET( input != NULL );
-    AES_VALIDATE_RET( output != NULL );
     AES_VALIDATE_RET( mode == MBEDTLS_AES_ENCRYPT ||
                       mode == MBEDTLS_AES_DECRYPT );
 
@@ -1014,12 +995,8 @@
     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
     unsigned char temp[16];
 
-    AES_VALIDATE_RET( ctx != NULL );
     AES_VALIDATE_RET( mode == MBEDTLS_AES_ENCRYPT ||
                       mode == MBEDTLS_AES_DECRYPT );
-    AES_VALIDATE_RET( iv != NULL );
-    AES_VALIDATE_RET( input != NULL );
-    AES_VALIDATE_RET( output != NULL );
 
     if( length % 16 )
         return( MBEDTLS_ERR_AES_INVALID_INPUT_LENGTH );
@@ -1123,12 +1100,8 @@
     unsigned char prev_tweak[16];
     unsigned char tmp[16];
 
-    AES_VALIDATE_RET( ctx != NULL );
     AES_VALIDATE_RET( mode == MBEDTLS_AES_ENCRYPT ||
                       mode == MBEDTLS_AES_DECRYPT );
-    AES_VALIDATE_RET( data_unit != NULL );
-    AES_VALIDATE_RET( input != NULL );
-    AES_VALIDATE_RET( output != NULL );
 
     /* Data units must be at least 16 bytes long. */
     if( length < 16 )
@@ -1232,13 +1205,8 @@
     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
     size_t n;
 
-    AES_VALIDATE_RET( ctx != NULL );
     AES_VALIDATE_RET( mode == MBEDTLS_AES_ENCRYPT ||
                       mode == MBEDTLS_AES_DECRYPT );
-    AES_VALIDATE_RET( iv_off != NULL );
-    AES_VALIDATE_RET( iv != NULL );
-    AES_VALIDATE_RET( input != NULL );
-    AES_VALIDATE_RET( output != NULL );
 
     n = *iv_off;
 
@@ -1301,12 +1269,8 @@
     unsigned char c;
     unsigned char ov[17];
 
-    AES_VALIDATE_RET( ctx != NULL );
     AES_VALIDATE_RET( mode == MBEDTLS_AES_ENCRYPT ||
                       mode == MBEDTLS_AES_DECRYPT );
-    AES_VALIDATE_RET( iv != NULL );
-    AES_VALIDATE_RET( input != NULL );
-    AES_VALIDATE_RET( output != NULL );
     while( length-- )
     {
         memcpy( ov, iv, 16 );
@@ -1345,12 +1309,6 @@
     int ret = 0;
     size_t n;
 
-    AES_VALIDATE_RET( ctx != NULL );
-    AES_VALIDATE_RET( iv_off != NULL );
-    AES_VALIDATE_RET( iv != NULL );
-    AES_VALIDATE_RET( input != NULL );
-    AES_VALIDATE_RET( output != NULL );
-
     n = *iv_off;
 
     if( n > 15 )
@@ -1392,13 +1350,6 @@
     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
     size_t n;
 
-    AES_VALIDATE_RET( ctx != NULL );
-    AES_VALIDATE_RET( nc_off != NULL );
-    AES_VALIDATE_RET( nonce_counter != NULL );
-    AES_VALIDATE_RET( stream_block != NULL );
-    AES_VALIDATE_RET( input != NULL );
-    AES_VALIDATE_RET( output != NULL );
-
     n = *nc_off;
 
     if ( n > 0x0F )