diff options
Diffstat (limited to 'core/lib/libtomcrypt/src/pk/asn1/der/bit/der_encode_bit_string.c')
| -rw-r--r-- | core/lib/libtomcrypt/src/pk/asn1/der/bit/der_encode_bit_string.c | 116 |
1 files changed, 116 insertions, 0 deletions
diff --git a/core/lib/libtomcrypt/src/pk/asn1/der/bit/der_encode_bit_string.c b/core/lib/libtomcrypt/src/pk/asn1/der/bit/der_encode_bit_string.c new file mode 100644 index 0000000..1776fc0 --- /dev/null +++ b/core/lib/libtomcrypt/src/pk/asn1/der/bit/der_encode_bit_string.c @@ -0,0 +1,116 @@ +/* + * 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_encode_bit_string.c + ASN.1 DER, encode a BIT STRING, Tom St Denis +*/ + + +#ifdef LTC_DER + +/** + Store a BIT STRING + @param in The array of bits to store (one per char) + @param inlen The number of bits tostore + @param out [out] The destination for the DER encoded BIT STRING + @param outlen [in/out] The max size and resulting size of the DER BIT STRING + @return CRYPT_OK if successful +*/ +int der_encode_bit_string(const unsigned char *in, unsigned long inlen, + unsigned char *out, unsigned long *outlen) +{ + unsigned long len, x, y; + unsigned char buf; + int err; + + LTC_ARGCHK(in != NULL); + LTC_ARGCHK(out != NULL); + LTC_ARGCHK(outlen != NULL); + + /* avoid overflows */ + if ((err = der_length_bit_string(inlen, &len)) != CRYPT_OK) { + return err; + } + + if (len > *outlen) { + *outlen = len; + return CRYPT_BUFFER_OVERFLOW; + } + + /* store header (include bit padding count in length) */ + x = 0; + y = (inlen >> 3) + ((inlen&7) ? 1 : 0) + 1; + + out[x++] = 0x03; + if (y < 128) { + out[x++] = (unsigned char)y; + } else if (y < 256) { + out[x++] = 0x81; + out[x++] = (unsigned char)y; + } else if (y < 65536) { + out[x++] = 0x82; + out[x++] = (unsigned char)((y>>8)&255); + out[x++] = (unsigned char)(y&255); + } + + /* store number of zero padding bits */ + out[x++] = (unsigned char)((8 - inlen) & 7); + + /* store the bits in big endian format */ + for (y = buf = 0; y < inlen; y++) { + buf |= (in[y] ? 1 : 0) << (7 - (y & 7)); + if ((y & 7) == 7) { + out[x++] = buf; + buf = 0; + } + } + /* store last byte */ + if (inlen & 7) { + out[x++] = buf; + } + *outlen = x; + return CRYPT_OK; +} + +#endif + +/* $Source: /cvs/libtom/libtomcrypt/src/pk/asn1/der/bit/der_encode_bit_string.c,v $ */ +/* $Revision: 1.5 $ */ +/* $Date: 2006/12/28 01:27:24 $ */ |