1 /* LibTomCrypt, modular cryptographic library -- Tom St Denis
3 * LibTomCrypt is a library that provides various cryptographic
4 * algorithms in a highly modular and flexible manner.
6 * The library is free for all purposes without any express
9 * Tom St Denis, tomstdenis@gmail.com, http://libtomcrypt.com
14 @file der_length_bit_string.c
15 ASN.1 DER, get length of BIT STRING, Tom St Denis
20 Gets length of DER encoding of BIT STRING
21 @param nbits The number of bits in the string to encode
22 @param outlen [out] The length of the DER encoding for the given string
23 @return CRYPT_OK if successful
25 int der_length_bit_string(unsigned long nbits, unsigned long *outlen)
28 LTC_ARGCHK(outlen != NULL);
30 /* get the number of the bytes */
31 nbytes = (nbits >> 3) + ((nbits & 7) ? 1 : 0) + 1;
34 /* 03 LL PP DD DD DD ... */
36 } else if (nbytes < 256) {
37 /* 03 81 LL PP DD DD DD ... */
39 } else if (nbytes < 65536) {
40 /* 03 82 LL LL PP DD DD DD ... */
43 return CRYPT_INVALID_ARG;
52 /* $Source: /cvs/libtom/libtomcrypt/src/pk/asn1/der/bit/der_length_bit_string.c,v $ */
53 /* $Revision: 1.2 $ */
54 /* $Date: 2006/03/31 14:15:35 $ */