--- a/libtomcrypt/src/pk/asn1/der/utf8/der_length_utf8_string.c	Thu Feb 08 23:11:40 2018 +0800
+++ b/libtomcrypt/src/pk/asn1/der/utf8/der_length_utf8_string.c	Fri Feb 09 21:44:05 2018 +0800
@@ -5,8 +5,6 @@
  *
  * The library is free for all purposes without any express
  * guarantee it works.
- *
- * Tom St Denis, [email protected], http://libtom.org
  */
 #include "tomcrypt.h"
 
@@ -27,15 +25,38 @@
       return 1;
    } else if (c <= 0x7FF) {
       return 2;
+#if LTC_WCHAR_MAX == 0xFFFF
+   } else {
+      return 3;
+   }
+#else
    } else if (c <= 0xFFFF) {
       return 3;
    } else {
       return 4;
    }
+#endif
 }
 
 /**
-  Gets length of DER encoding of UTF8 STRING 
+  Test whether the given code point is valid character
+  @param c   The UTF-8 character to test
+  @return    1 - valid, 0 - invalid
+*/
+int der_utf8_valid_char(const wchar_t c)
+{
+   LTC_UNUSED_PARAM(c);
+#if !defined(LTC_WCHAR_MAX) || LTC_WCHAR_MAX > 0xFFFF
+   if (c > 0x10FFFF) return 0;
+#endif
+#if LTC_WCHAR_MAX != 0xFFFF && LTC_WCHAR_MAX != 0xFFFFFFFF
+   if (c < 0) return 0;
+#endif
+   return 1;
+}
+
+/**
+  Gets length of DER encoding of UTF8 STRING
   @param in       The characters to measure the length of
   @param noctets  The number of octets in the string to encode
   @param outlen   [out] The length of the DER encoding for the given string
@@ -50,9 +71,7 @@
 
    len = 0;
    for (x = 0; x < noctets; x++) {
-      if (in[x] < 0 || in[x] > 0x10FFFF) {
-         return CRYPT_INVALID_ARG;
-      }
+      if (!der_utf8_valid_char(in[x])) return CRYPT_INVALID_ARG;
       len += der_utf8_charsize(in[x]);
    }
 
@@ -78,6 +97,6 @@
 #endif
 
 
-/* $Source$ */
-/* $Revision$ */
-/* $Date$ */
+/* ref:         $Format:%D$ */
+/* git commit:  $Format:%H$ */
+/* commit time: $Format:%ai$ */