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#include "includes.h"
#include "options.h"
#include "ecc.h"
#ifdef DROPBEAR_ECC
#ifdef DROPBEAR_ECC_256
const struct ecc_curve_secp256r1 {
.ltc_set = <c_ecc_sets[0],
.hash_desc = sha256_desc,
.name = "secp256r1"
};
#endif
#ifdef DROPBEAR_ECC_384
const struct ecc_curve_secp384r1 {
.ltc_set = <c_ecc_sets[1],
.hash_desc = sha384_desc,
.name = "secp384r1"
};
#endif
#ifdef DROPBEAR_ECC_256
const struct ecc_curve_secp256r1 {
.ltc_set = <c_ecc_sets[0],
.hash_desc = sha256_desc,
.name = "secp256r1"
};
#endif
void buf_put_ecc_key_string(buffer *buf, ecc_key *key) {
// XXX point compression
int len = key->dp->size*2 + 1;
buf_putint(len);
int err = ecc_ansi_x963_export(key, buf_getwriteptr(buf, len), &len);
if (err != CRYPT_OK) {
dropbear_exit("ECC error");
}
buf_incrwritepos(buf, len);
}
int buf_get_ecc_key_string(buffer *buf, ecc_key *key) {
}
// a modified version of libtomcrypt's "ecc_shared_secret" to output
// a mp_int instead.
mp_int * dropbear_ecc_shared_secret(ecc_key *public_key, ecc_key *private_key)
{
ecc_point *result = NULL
mp_int *prime = NULL, *shared_secret = NULL;
int ret = DROPBEAR_FAILURE;
/* type valid? */
if (private_key->type != PK_PRIVATE) {
goto done;
}
if (private_key->dp != public_key->dp) {
goto done;
}
#if 0
// XXX - possibly not neccessary tests?
if (ltc_ecc_is_valid_idx(private_key->idx) == 0 || ltc_ecc_is_valid_idx(public_key->idx) == 0) {
goto done;
}
if (XSTRCMP(private_key->dp->name, public_key->dp->name) != 0) {
goto done;
}
#endif
/* make new point */
result = ltc_ecc_new_point();
if (result == NULL) {
goto done;
}
prime = m_malloc(sizeof(*prime));
m_mp_init(prime);
if (mp_read_radix(prime, (char *)private_key->dp->prime, 16) != CRYPT_OK) {
goto done;
}
if (ltc_mp.ecc_ptmul(private_key->k, &public_key->pubkey, result, prime, 1) != CRYPT_OK) {
goto done;
}
err = DROPBEAR_SUCCESS;
done:
if (err == DROPBEAR_SUCCESS) {
shared_secret = prime;
prime = NULL;
}
if (prime) {
mp_clear(prime);
m_free(prime);
}
ltc_ecc_del_point(result);
if (err == DROPBEAR_FAILURE) {
dropbear_exit("ECC error");
}
return shared_secret;
return err;
}
}
#endif
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