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/* LibTomCrypt, modular cryptographic library -- Tom St Denis
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* LibTomCrypt is a library that provides various cryptographic
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* algorithms in a highly modular and flexible manner.
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* The library is free for all purposes without any express
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* Tom St Denis, tomstdenis@gmail.com, http://libtomcrypt.org
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@file der_length_short_integer.c
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ASN.1 DER, get length of encoding, Tom St Denis
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Gets length of DER encoding of num
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@param num The integer to get the size of
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@param outlen [out] The length of the DER encoding for the given integer
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@return CRYPT_OK if successful
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int der_length_short_integer(unsigned long num, unsigned long *outlen)
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unsigned long z, y, len;
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LTC_ARGCHK(outlen != NULL);
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/* force to 32 bits */
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/* get the number of bytes */
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/* we need a 0x02 to indicate it's INTEGER */
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/* see if msb is set */
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len += (num&(1UL<<((z<<3) - 1))) ? 1 : 0;
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/* $Source: /cvs/libtom/libtomcrypt/src/pk/asn1/der/short_integer/der_length_short_integer.c,v $ */
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/* $Revision: 1.3 $ */
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/* $Date: 2005/05/23 01:35:38 $ */