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/*
* Copyright (c) 2001-2007, Tom St Denis
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/* 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://libtom.org
*/
#include "tomcrypt.h"
/**
@file der_length_octet_string.c
ASN.1 DER, get length of OCTET STRING, Tom St Denis
*/
#ifdef LTC_DER
/**
Gets length of DER encoding of OCTET STRING
@param noctets The number of octets in the string to encode
@param outlen [out] The length of the DER encoding for the given string
@return CRYPT_OK if successful
*/
int der_length_octet_string(unsigned long noctets, unsigned long *outlen)
{
LTC_ARGCHK(outlen != NULL);
if (noctets < 128) {
/* 04 LL DD DD DD ... */
*outlen = 2 + noctets;
} else if (noctets < 256) {
/* 04 81 LL DD DD DD ... */
*outlen = 3 + noctets;
} else if (noctets < 65536UL) {
/* 04 82 LL LL DD DD DD ... */
*outlen = 4 + noctets;
} else if (noctets < 16777216UL) {
/* 04 83 LL LL LL DD DD DD ... */
*outlen = 5 + noctets;
} else {
return CRYPT_INVALID_ARG;
}
return CRYPT_OK;
}
#endif
/* $Source: /cvs/libtom/libtomcrypt/src/pk/asn1/der/octet/der_length_octet_string.c,v $ */
/* $Revision: 1.3 $ */
/* $Date: 2006/12/28 01:27:24 $ */
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