/* 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, tomstdenis@gmail.com, http://libtomcrypt.com */#include "tomcrypt.h"/**  @file der_decode_utf8_string.c  ASN.1 DER, encode a UTF8 STRING, Tom St Denis*/#ifdef LTC_DER/**  Store a UTF8 STRING  @param in      The DER encoded UTF8 STRING  @param inlen   The size of the DER UTF8 STRING  @param out     [out] The array of utf8s stored (one per char)  @param outlen  [in/out] The number of utf8s stored  @return CRYPT_OK if successful*/int der_decode_utf8_string(const unsigned char *in,  unsigned long inlen,                                       wchar_t *out, unsigned long *outlen){   wchar_t       tmp;   unsigned long x, y, z, len;   LTC_ARGCHK(in     != NULL);   LTC_ARGCHK(out    != NULL);   LTC_ARGCHK(outlen != NULL);   /* must have header at least */   if (inlen < 2) {      return CRYPT_INVALID_PACKET;   }   /* check for 0x0C */   if ((in[0] & 0x1F) != 0x0C) {      return CRYPT_INVALID_PACKET;   }   x = 1;   /* decode the length */   if (in[x] & 0x80) {      /* valid # of bytes in length are 1,2,3 */      y = in[x] & 0x7F;      if ((y == 0) || (y > 3) || ((x + y) > inlen)) {         return CRYPT_INVALID_PACKET;      }      /* read the length in */      len = 0;      ++x;      while (y--) {         len = (len << 8) | in[x++];      }   } else {      len = in[x++] & 0x7F;   }   if (len + x > inlen) {      return CRYPT_INVALID_PACKET;   }   /* proceed to decode */   for (y = 0; x < inlen; ) {      /* get first byte */      tmp = in[x++];       /* count number of bytes */      for (z = 0; (tmp & 0x80) && (z <= 4); z++, tmp = (tmp << 1) & 0xFF);            if (z > 4 || (x + (z - 1) > inlen)) {         return CRYPT_INVALID_PACKET;      }      /* decode, grab upper bits */      tmp >>= z;      /* grab remaining bytes */      if (z > 1) { --z; }      while (z-- != 0) {         if ((in[x] & 0xC0) != 0x80) {            return CRYPT_INVALID_PACKET;         }         tmp = (tmp << 6) | ((wchar_t)in[x++] & 0x3F);      }      if (y > *outlen) {         *outlen = y;         return CRYPT_BUFFER_OVERFLOW;      }      out[y++] = tmp;   }   *outlen = y;   return CRYPT_OK;} #endif/* $Source: /cvs/libtom/libtomcrypt/src/pk/asn1/der/utf8/der_decode_utf8_string.c,v $ *//* $Revision: 1.7 $ *//* $Date: 2006/11/26 02:27:37 $ */