diff --git a/library/aes.c b/library/aes.c
index a2d1b6d..9c7d3d0 100644
--- a/library/aes.c
+++ b/library/aes.c
@@ -1626,6 +1626,74 @@
     { 16, 32, 36 };
 #endif /* MBEDTLS_CIPHER_MODE_CTR */
 
+#if defined(MBEDTLS_CIPHER_MODE_XTS)
+/*
+ * AES-XTS test vectors from:
+ *
+ * IEEE P1619/D16 Annex B
+ * https://web.archive.org/web/20150629024421/http://grouper.ieee.org/groups/1619/email/pdf00086.pdf
+ * (Archived from original at http://grouper.ieee.org/groups/1619/email/pdf00086.pdf)
+ */
+static const unsigned char aes_test_xts_key[][32] =
+{
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
+    { 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11,
+      0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11,
+      0x22, 0x22, 0x22, 0x22, 0x22, 0x22, 0x22, 0x22,
+      0x22, 0x22, 0x22, 0x22, 0x22, 0x22, 0x22, 0x22 },
+    { 0xff, 0xfe, 0xfd, 0xfc, 0xfb, 0xfa, 0xf9, 0xf8,
+      0xf7, 0xf6, 0xf5, 0xf4, 0xf3, 0xf2, 0xf1, 0xf0,
+      0x22, 0x22, 0x22, 0x22, 0x22, 0x22, 0x22, 0x22,
+      0x22, 0x22, 0x22, 0x22, 0x22, 0x22, 0x22, 0x22 },
+};
+
+static const unsigned char aes_test_xts_pt32[][32] =
+{
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
+    { 0x44, 0x44, 0x44, 0x44, 0x44, 0x44, 0x44, 0x44,
+      0x44, 0x44, 0x44, 0x44, 0x44, 0x44, 0x44, 0x44,
+      0x44, 0x44, 0x44, 0x44, 0x44, 0x44, 0x44, 0x44,
+      0x44, 0x44, 0x44, 0x44, 0x44, 0x44, 0x44, 0x44 },
+    { 0x44, 0x44, 0x44, 0x44, 0x44, 0x44, 0x44, 0x44,
+      0x44, 0x44, 0x44, 0x44, 0x44, 0x44, 0x44, 0x44,
+      0x44, 0x44, 0x44, 0x44, 0x44, 0x44, 0x44, 0x44,
+      0x44, 0x44, 0x44, 0x44, 0x44, 0x44, 0x44, 0x44 },
+};
+
+static const unsigned char aes_test_xts_ct32[][32] =
+{
+    { 0x91, 0x7c, 0xf6, 0x9e, 0xbd, 0x68, 0xb2, 0xec,
+      0x9b, 0x9f, 0xe9, 0xa3, 0xea, 0xdd, 0xa6, 0x92,
+      0xcd, 0x43, 0xd2, 0xf5, 0x95, 0x98, 0xed, 0x85,
+      0x8c, 0x02, 0xc2, 0x65, 0x2f, 0xbf, 0x92, 0x2e },
+    { 0xc4, 0x54, 0x18, 0x5e, 0x6a, 0x16, 0x93, 0x6e,
+      0x39, 0x33, 0x40, 0x38, 0xac, 0xef, 0x83, 0x8b,
+      0xfb, 0x18, 0x6f, 0xff, 0x74, 0x80, 0xad, 0xc4,
+      0x28, 0x93, 0x82, 0xec, 0xd6, 0xd3, 0x94, 0xf0 },
+    { 0xaf, 0x85, 0x33, 0x6b, 0x59, 0x7a, 0xfc, 0x1a,
+      0x90, 0x0b, 0x2e, 0xb2, 0x1e, 0xc9, 0x49, 0xd2,
+      0x92, 0xdf, 0x4c, 0x04, 0x7e, 0x0b, 0x21, 0x53,
+      0x21, 0x86, 0xa5, 0x97, 0x1a, 0x22, 0x7a, 0x89 },
+};
+
+static const unsigned char aes_test_xts_data_unit[][16] =
+{
+   { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+     0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
+   { 0x33, 0x33, 0x33, 0x33, 0x33, 0x00, 0x00, 0x00,
+     0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
+   { 0x33, 0x33, 0x33, 0x33, 0x33, 0x00, 0x00, 0x00,
+     0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
+};
+
+#endif /* MBEDTLS_CIPHER_MODE_XTS */
+
 /*
  * Checkup routine
  */
@@ -1969,6 +2037,73 @@
         mbedtls_printf( "\n" );
 #endif /* MBEDTLS_CIPHER_MODE_CTR */
 
+#if defined(MBEDTLS_CIPHER_MODE_XTS)
+    {
+    static const int num_tests =
+        sizeof(aes_test_xts_key) / sizeof(*aes_test_xts_key);
+    mbedtls_aes_xts_context ctx_xts;
+
+    /*
+     * XTS mode
+     */
+    mbedtls_aes_xts_init( &ctx_xts );
+
+    for( i = 0; i < num_tests << 1; i++ )
+    {
+        const unsigned char *data_unit;
+        u = i >> 1;
+        mode = i & 1;
+
+        if( verbose != 0 )
+            mbedtls_printf( "  AES-XTS-128 (%s): ",
+                            ( mode == MBEDTLS_AES_DECRYPT ) ? "dec" : "enc" );
+
+        memset( key, 0, sizeof( key ) );
+        memcpy( key, aes_test_xts_key[u], 32 );
+        data_unit = aes_test_xts_data_unit[u];
+
+        len = sizeof( *aes_test_xts_ct32 );
+
+        if( mode == MBEDTLS_AES_DECRYPT )
+        {
+            ret = mbedtls_aes_xts_setkey_dec( &ctx_xts, key, 256 );
+            if( ret != 0)
+                goto exit;
+            memcpy( buf, aes_test_xts_ct32[u], len );
+            aes_tests = aes_test_xts_pt32[u];
+        }
+        else
+        {
+            ret = mbedtls_aes_xts_setkey_enc( &ctx_xts, key, 256 );
+            if( ret != 0)
+                goto exit;
+            memcpy( buf, aes_test_xts_pt32[u], len );
+            aes_tests = aes_test_xts_ct32[u];
+        }
+
+
+        ret = mbedtls_aes_crypt_xts( &ctx_xts, mode, len, data_unit,
+                                     buf, buf );
+        if( ret != 0 )
+            goto exit;
+
+        if( memcmp( buf, aes_tests, len ) != 0 )
+        {
+            ret = 1;
+            goto exit;
+        }
+
+        if( verbose != 0 )
+            mbedtls_printf( "passed\n" );
+    }
+
+    if( verbose != 0 )
+        mbedtls_printf( "\n" );
+
+    mbedtls_aes_xts_free( &ctx_xts );
+    }
+#endif /* MBEDTLS_CIPHER_MODE_XTS */
+
     ret = 0;
 
 exit: