diff --git a/library/aes.c b/library/aes.c
index 3de571e..0543cd7 100644
--- a/library/aes.c
+++ b/library/aes.c
@@ -56,6 +56,12 @@
 
 #if !defined(MBEDTLS_AES_ALT)
 
+/* Parameter validation macros based on platform_util.h */
+#define AES_VALIDATE_RET( cond )    \
+    MBEDTLS_INTERNAL_VALIDATE_RET( cond, MBEDTLS_ERR_AES_BAD_INPUT_DATA )
+#define AES_VALIDATE( cond )        \
+    MBEDTLS_INTERNAL_VALIDATE( cond )
+
 /*
  * 32-bit integer manipulation macros (little endian)
  */
@@ -511,6 +517,8 @@
 
 void mbedtls_aes_init( mbedtls_aes_context *ctx )
 {
+    AES_VALIDATE( ctx != NULL );
+
     memset( ctx, 0, sizeof( mbedtls_aes_context ) );
 }
 
@@ -525,12 +533,17 @@
 #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 );
 }
 
 void mbedtls_aes_xts_free( mbedtls_aes_xts_context *ctx )
 {
+    if( ctx == NULL )
+        return;
+
     mbedtls_aes_free( &ctx->crypt );
     mbedtls_aes_free( &ctx->tweak );
 }
@@ -546,14 +559,8 @@
     unsigned int i;
     uint32_t *RK;
 
-#if !defined(MBEDTLS_AES_ROM_TABLES)
-    if( aes_init_done == 0 )
-    {
-        aes_gen_tables();
-        aes_init_done = 1;
-
-    }
-#endif
+    AES_VALIDATE_RET( ctx != NULL );
+    AES_VALIDATE_RET( key != NULL );
 
     switch( keybits )
     {
@@ -563,6 +570,14 @@
         default : return( MBEDTLS_ERR_AES_INVALID_KEY_LENGTH );
     }
 
+#if !defined(MBEDTLS_AES_ROM_TABLES)
+    if( aes_init_done == 0 )
+    {
+        aes_gen_tables();
+        aes_init_done = 1;
+    }
+#endif
+
 #if defined(MBEDTLS_PADLOCK_C) && defined(MBEDTLS_PADLOCK_ALIGN16)
     if( aes_padlock_ace == -1 )
         aes_padlock_ace = mbedtls_padlock_has_support( MBEDTLS_PADLOCK_ACE );
@@ -662,6 +677,9 @@
     uint32_t *RK;
     uint32_t *SK;
 
+    AES_VALIDATE_RET( ctx != NULL );
+    AES_VALIDATE_RET( key != NULL );
+
     mbedtls_aes_init( &cty );
 
 #if defined(MBEDTLS_PADLOCK_C) && defined(MBEDTLS_PADLOCK_ALIGN16)
@@ -752,6 +770,9 @@
     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 )
@@ -774,6 +795,9 @@
     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 )
@@ -977,10 +1001,16 @@
  * AES-ECB block encryption/decryption
  */
 int mbedtls_aes_crypt_ecb( mbedtls_aes_context *ctx,
-                    int mode,
-                    const unsigned char input[16],
-                    unsigned char output[16] )
+                           int mode,
+                           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 );
+
 #if defined(MBEDTLS_AESNI_C) && defined(MBEDTLS_HAVE_X86_64)
     if( mbedtls_aesni_has_support( MBEDTLS_AESNI_AES ) )
         return( mbedtls_aesni_crypt_ecb( ctx, mode, input, output ) );
@@ -1018,6 +1048,13 @@
     int i;
     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 );
 
@@ -1143,6 +1180,13 @@
     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 )
         return MBEDTLS_ERR_AES_INVALID_INPUT_LENGTH;
@@ -1242,7 +1286,20 @@
                        unsigned char *output )
 {
     int c;
-    size_t n = *iv_off;
+    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;
+
+    if( n > 15 )
+        return( MBEDTLS_ERR_AES_BAD_INPUT_DATA );
 
     if( mode == MBEDTLS_AES_DECRYPT )
     {
@@ -1280,15 +1337,21 @@
  * AES-CFB8 buffer encryption/decryption
  */
 int mbedtls_aes_crypt_cfb8( mbedtls_aes_context *ctx,
-                       int mode,
-                       size_t length,
-                       unsigned char iv[16],
-                       const unsigned char *input,
-                       unsigned char *output )
+                            int mode,
+                            size_t length,
+                            unsigned char iv[16],
+                            const unsigned char *input,
+                            unsigned char *output )
 {
     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 );
@@ -1321,7 +1384,18 @@
                            unsigned char *output )
 {
     int ret = 0;
-    size_t n = *iv_off;
+    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 )
+        return( MBEDTLS_ERR_AES_BAD_INPUT_DATA );
 
     while( length-- )
     {
@@ -1356,7 +1430,16 @@
                        unsigned char *output )
 {
     int c, i;
-    size_t n = *nc_off;
+    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 )
         return( MBEDTLS_ERR_AES_BAD_INPUT_DATA );