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
12 @file der_length_bit_string.c
13 ASN.1 DER, get length of BIT STRING, Tom St Denis
18 Gets length of DER encoding of BIT STRING
19 @param nbits The number of bits in the string to encode
20 @param outlen [out] The length of the DER encoding for the given string
21 @return CRYPT_OK if successful
23 int der_length_bit_string(unsigned long nbits, unsigned long *outlen)
26 LTC_ARGCHK(outlen != NULL);
28 /* get the number of the bytes */
29 nbytes = (nbits >> 3) + ((nbits & 7) ? 1 : 0) + 1;
32 /* 03 LL PP DD DD DD ... */
34 } else if (nbytes < 256) {
35 /* 03 81 LL PP DD DD DD ... */
37 } else if (nbytes < 65536) {
38 /* 03 82 LL LL PP DD DD DD ... */
41 return CRYPT_INVALID_ARG;
50 /* ref: $Format:%D$ */
51 /* git commit: $Format:%H$ */
52 /* commit time: $Format:%ai$ */