| /* 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://libtomcrypt.com |
| */ |
| |
| /* Implements ECC over Z/pZ for curve y^2 = x^3 - 3x + b |
| * |
| * All curves taken from NIST recommendation paper of July 1999 |
| * Available at http://csrc.nist.gov/cryptval/dss.htm |
| */ |
| #include "tomcrypt.h" |
| |
| /** |
| @file ecc_export.c |
| ECC Crypto, Tom St Denis |
| */ |
| |
| #ifdef MECC |
| |
| /** |
| Export an ECC key as a binary packet |
| @param out [out] Destination for the key |
| @param outlen [in/out] Max size and resulting size of the exported key |
| @param type The type of key you want to export (PK_PRIVATE or PK_PUBLIC) |
| @param key The key to export |
| @return CRYPT_OK if successful |
| */ |
| int ecc_export(unsigned char *out, unsigned long *outlen, int type, ecc_key *key) |
| { |
| int err; |
| unsigned char flags[1]; |
| unsigned long key_size; |
| |
| LTC_ARGCHK(out != NULL); |
| LTC_ARGCHK(outlen != NULL); |
| LTC_ARGCHK(key != NULL); |
| |
| /* type valid? */ |
| if (key->type != PK_PRIVATE && type == PK_PRIVATE) { |
| return CRYPT_PK_TYPE_MISMATCH; |
| } |
| |
| if (ltc_ecc_is_valid_idx(key->idx) == 0) { |
| return CRYPT_INVALID_ARG; |
| } |
| |
| /* we store the NIST byte size */ |
| key_size = key->dp->size; |
| |
| if (type == PK_PRIVATE) { |
| flags[0] = 1; |
| err = der_encode_sequence_multi(out, outlen, |
| LTC_ASN1_BIT_STRING, 1UL, flags, |
| LTC_ASN1_SHORT_INTEGER, 1UL, &key_size, |
| LTC_ASN1_INTEGER, 1UL, key->pubkey.x, |
| LTC_ASN1_INTEGER, 1UL, key->pubkey.y, |
| LTC_ASN1_INTEGER, 1UL, key->k, |
| LTC_ASN1_EOL, 0UL, NULL); |
| } else { |
| flags[0] = 0; |
| err = der_encode_sequence_multi(out, outlen, |
| LTC_ASN1_BIT_STRING, 1UL, flags, |
| LTC_ASN1_SHORT_INTEGER, 1UL, &key_size, |
| LTC_ASN1_INTEGER, 1UL, key->pubkey.x, |
| LTC_ASN1_INTEGER, 1UL, key->pubkey.y, |
| LTC_ASN1_EOL, 0UL, NULL); |
| } |
| |
| return err; |
| } |
| |
| #endif |
| /* $Source: /cvs/libtom/libtomcrypt/src/pk/ecc/ecc_export.c,v $ */ |
| /* $Revision: 1.4 $ */ |
| /* $Date: 2006/11/21 00:10:18 $ */ |
| |