/**
* @brief Get random bytes
*
* Make sure to always check the return code of this function!
*
* @param[in] where The buffer to fill with random bytes
*
* @param[in] len The size of the buffer to fill.
*
* @param[in] strong Use a strong or private RNG source.
*
* @return 1 on success, 0 on error.
*/
int ssh_get_random(void *where, int len, int strong)
{
#ifdef HAVE_OPENSSL_RAND_PRIV_BYTES
if (strong) {
/* Returns -1 when not supported, 0 on error, 1 on success */
return !!RAND_priv_bytes(where, len);
}
#else
(void)strong;
#endif /* HAVE_RAND_PRIV_BYTES */
/* Returns -1 when not supported, 0 on error, 1 on success */
return !!RAND_bytes(where, len);
}
/* Setup EVP_PKEY using public, private or generation */
static int ecx_key_op(EVP_PKEY *pkey, int id, const X509_ALGOR *palg,
const unsigned char *p, int plen, ecx_key_op_t op)
{
ECX_KEY *key = NULL;
unsigned char *privkey, *pubkey;
if (op != KEY_OP_KEYGEN) {
if (palg != NULL) {
int ptype;
/* Algorithm parameters must be absent */
X509_ALGOR_get0(NULL, &ptype, NULL, palg);
if (ptype != V_ASN1_UNDEF) {
ECerr(EC_F_ECX_KEY_OP, EC_R_INVALID_ENCODING);
return 0;
}
}
if (p == NULL || plen != KEYLENID(id)) {
ECerr(EC_F_ECX_KEY_OP, EC_R_INVALID_ENCODING);
return 0;
}
}
key = OPENSSL_zalloc(sizeof(*key));
if (key == NULL) {
ECerr(EC_F_ECX_KEY_OP, ERR_R_MALLOC_FAILURE);
return 0;
}
pubkey = key->pubkey;
if (op == KEY_OP_PUBLIC) {
memcpy(pubkey, p, plen);
} else {
privkey = key->privkey = OPENSSL_secure_malloc(KEYLENID(id));
if (privkey == NULL) {
ECerr(EC_F_ECX_KEY_OP, ERR_R_MALLOC_FAILURE);
goto err;
}
if (op == KEY_OP_KEYGEN) {
if (RAND_priv_bytes(privkey, KEYLENID(id)) <= 0) {
OPENSSL_secure_free(privkey);
key->privkey = NULL;
goto err;
}
if (id == EVP_PKEY_X25519) {
privkey[0] &= 248;
privkey[X25519_KEYLEN - 1] &= 127;
privkey[X25519_KEYLEN - 1] |= 64;
} else if (id == EVP_PKEY_X448) {
privkey[0] &= 252;
privkey[X448_KEYLEN - 1] |= 128;
}
} else {
memcpy(privkey, p, KEYLENID(id));
}
switch (id) {
case EVP_PKEY_X25519:
X25519_public_from_private(pubkey, privkey);
break;
case EVP_PKEY_ED25519:
ED25519_public_from_private(pubkey, privkey);
break;
case EVP_PKEY_X448:
X448_public_from_private(pubkey, privkey);
break;
case EVP_PKEY_ED448:
ED448_public_from_private(pubkey, privkey);
break;
}
}
EVP_PKEY_assign(pkey, id, key);
return 1;
err:
OPENSSL_free(key);
return 0;
}
