--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libtomcrypt/src/pk/asn1/der/utf8/der_encode_utf8_string.c	Sat Feb 03 08:20:34 2007 +0000
@@ -0,0 +1,105 @@
+/* LibTomCrypt, modular cryptographic library -- Tom St Denis
+ *
+ * LibTomCrypt is a library that provides various cryptographic
+ * algorithms in a highly modular and flexible manner.
+ *
+ * The library is free for all purposes without any express
+ * guarantee it works.
+ *
+ * Tom St Denis, [email protected], http://libtomcrypt.com
+ */
+#include "tomcrypt.h"
+
+/**
+  @file der_encode_utf8_string.c
+  ASN.1 DER, encode a UTF8 STRING, Tom St Denis
+*/
+
+
+#ifdef LTC_DER
+
+/**
+  Store an UTF8 STRING
+  @param in       The array of UTF8 to store (one per wchar_t)
+  @param inlen    The number of UTF8 to store
+  @param out      [out] The destination for the DER encoded UTF8 STRING
+  @param outlen   [in/out] The max size and resulting size of the DER UTF8 STRING
+  @return CRYPT_OK if successful
+*/
+int der_encode_utf8_string(const wchar_t *in,  unsigned long inlen,
+                           unsigned char *out, unsigned long *outlen)
+{
+   unsigned long x, y, len;
+
+   LTC_ARGCHK(in     != NULL);
+   LTC_ARGCHK(out    != NULL);
+   LTC_ARGCHK(outlen != NULL);
+
+   /* get the size */
+   for (x = len = 0; x < inlen; x++) {
+       if (in[x] < 0 || in[x] > 0x1FFFF) { 
+          return CRYPT_INVALID_ARG;
+       }
+       len += der_utf8_charsize(in[x]);
+   }
+
+   if (len < 128) {
+      y = 2 + len;
+   } else if (len < 256) {
+      y = 3 + len;
+   } else if (len < 65536UL) {
+      y = 4 + len;
+   } else if (len < 16777216UL) {
+      y = 5 + len;
+   } else {
+      return CRYPT_INVALID_ARG;
+   }
+
+   /* too big? */
+   if (y > *outlen) {
+      *outlen = len;
+      return CRYPT_BUFFER_OVERFLOW;
+   }
+
+   /* encode the header+len */
+   x = 0;
+   out[x++] = 0x0C;
+   if (len < 128) {
+      out[x++] = len;
+   } else if (len < 256) {
+      out[x++] = 0x81;
+      out[x++] = len;
+   } else if (len < 65536UL) {
+      out[x++] = 0x82;
+      out[x++] = (len>>8)&255;
+      out[x++] = len&255;
+   } else if (len < 16777216UL) {
+      out[x++] = 0x83;
+      out[x++] = (len>>16)&255;
+      out[x++] = (len>>8)&255;
+      out[x++] = len&255;
+   } else {
+      return CRYPT_INVALID_ARG;
+   }
+
+   /* store UTF8 */
+   for (y = 0; y < inlen; y++) {
+       switch (der_utf8_charsize(in[y])) {
+          case 1: out[x++] = in[y]; break;
+          case 2: out[x++] = 0xC0 | ((in[y] >> 6) & 0x1F);  out[x++] = 0x80 | (in[y] & 0x3F); break;
+          case 3: out[x++] = 0xE0 | ((in[y] >> 12) & 0x0F); out[x++] = 0x80 | ((in[y] >> 6) & 0x3F); out[x++] = 0x80 | (in[y] & 0x3F); break;
+          case 4: out[x++] = 0xF0 | ((in[y] >> 18) & 0x07); out[x++] = 0x80 | ((in[y] >> 12) & 0x3F); out[x++] = 0x80 | ((in[y] >> 6) & 0x3F); out[x++] = 0x80 | (in[y] & 0x3F); break;
+       }
+   }
+
+   /* retun length */
+   *outlen = x;
+
+   return CRYPT_OK;
+}
+
+#endif
+
+/* $Source: /cvs/libtom/libtomcrypt/src/pk/asn1/der/utf8/der_encode_utf8_string.c,v $ */
+/* $Revision: 1.7 $ */
+/* $Date: 2006/12/16 17:41:21 $ */