diff options
Diffstat (limited to 'core/lib/libtomcrypt/src/pk/ecc/ecc_make_key.c')
| -rw-r--r-- | core/lib/libtomcrypt/src/pk/ecc/ecc_make_key.c | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/core/lib/libtomcrypt/src/pk/ecc/ecc_make_key.c b/core/lib/libtomcrypt/src/pk/ecc/ecc_make_key.c new file mode 100644 index 0000000..4e9f547 --- /dev/null +++ b/core/lib/libtomcrypt/src/pk/ecc/ecc_make_key.c @@ -0,0 +1,156 @@ +/* + * 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 + */ + +/* 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_make_key.c + ECC Crypto, Tom St Denis +*/ + +#ifdef LTC_MECC + +/** + Make a new ECC key + @param prng An active PRNG state + @param wprng The index of the PRNG you wish to use + @param keysize The keysize for the new key (in octets from 20 to 65 bytes) + @param key [out] Destination of the newly created key + @return CRYPT_OK if successful, upon error all allocated memory will be freed +*/ +int ecc_make_key(prng_state *prng, int wprng, int keysize, ecc_key *key) +{ + int x, err; + + /* find key size */ + for (x = 0; (keysize > ltc_ecc_sets[x].size) && (ltc_ecc_sets[x].size != 0); x++); + keysize = ltc_ecc_sets[x].size; + + if (keysize > ECC_MAXSIZE || ltc_ecc_sets[x].size == 0) { + return CRYPT_INVALID_KEYSIZE; + } + err = ecc_make_key_ex(prng, wprng, key, <c_ecc_sets[x]); + key->idx = x; + return err; +} + +int ecc_make_key_ex(prng_state *prng, int wprng, ecc_key *key, const ltc_ecc_set_type *dp) +{ + int err; + ecc_point *base; + void *prime, *order; + unsigned char *buf; + int keysize; + + LTC_ARGCHK(key != NULL); + LTC_ARGCHK(ltc_mp.name != NULL); + LTC_ARGCHK(dp != NULL); + + /* good prng? */ + if ((err = prng_is_valid(wprng)) != CRYPT_OK) { + return err; + } + + key->idx = -1; + key->dp = dp; + keysize = dp->size; + + /* allocate ram */ + base = NULL; + buf = XMALLOC(ECC_MAXSIZE); + if (buf == NULL) { + return CRYPT_MEM; + } + + /* make up random string */ + if (prng_descriptor[wprng]->read(buf, (unsigned long)keysize, prng) != (unsigned long)keysize) { + err = CRYPT_ERROR_READPRNG; + goto ERR_BUF; + } + + /* setup the key variables */ + if ((err = mp_init_multi(&key->pubkey.x, &key->pubkey.y, &key->pubkey.z, &key->k, &prime, &order, NULL)) != CRYPT_OK) { + goto ERR_BUF; + } + base = ltc_ecc_new_point(); + if (base == NULL) { + err = CRYPT_MEM; + goto errkey; + } + + /* read in the specs for this key */ + if ((err = mp_read_radix(prime, (char *)key->dp->prime, 16)) != CRYPT_OK) { goto errkey; } + if ((err = mp_read_radix(order, (char *)key->dp->order, 16)) != CRYPT_OK) { goto errkey; } + if ((err = mp_read_radix(base->x, (char *)key->dp->Gx, 16)) != CRYPT_OK) { goto errkey; } + if ((err = mp_read_radix(base->y, (char *)key->dp->Gy, 16)) != CRYPT_OK) { goto errkey; } + if ((err = mp_set(base->z, 1)) != CRYPT_OK) { goto errkey; } + if ((err = mp_read_unsigned_bin(key->k, (unsigned char *)buf, keysize)) != CRYPT_OK) { goto errkey; } + + /* the key should be smaller than the order of base point */ + if (mp_cmp(key->k, order) != LTC_MP_LT) { + if((err = mp_mod(key->k, order, key->k)) != CRYPT_OK) { goto errkey; } + } + /* make the public key */ + if ((err = ltc_mp.ecc_ptmul(key->k, base, &key->pubkey, prime, 1)) != CRYPT_OK) { goto errkey; } + key->type = PK_PRIVATE; + + /* free up ram */ + err = CRYPT_OK; + goto cleanup; +errkey: + mp_clear_multi(key->pubkey.x, key->pubkey.y, key->pubkey.z, key->k, NULL); +cleanup: + ltc_ecc_del_point(base); + mp_clear_multi(prime, order, NULL); +ERR_BUF: +#ifdef LTC_CLEAN_STACK + zeromem(buf, ECC_MAXSIZE); +#endif + XFREE(buf); + return err; +} + +#endif +/* $Source: /cvs/libtom/libtomcrypt/src/pk/ecc/ecc_make_key.c,v $ */ +/* $Revision: 1.13 $ */ +/* $Date: 2007/05/12 14:32:35 $ */ |