EAP-pwd: Verify BN_rand_range return code

This makes the EAP-pwd server and peer implementations more robust
should OpenSSL fail to derive random number for some reason. While this
is unlikely to happen in practice, the implementation better be prepared
for this should something unexpected ever happen. See
http://jbp.io/2014/01/16/openssl-rand-api/#review-of-randbytes-callers
for more details.

Signed-off-by: Florent Daigniere <nextgens@freenetproject.org>
This commit is contained in:
Florent Daigniere 2014-06-27 12:24:30 +02:00 committed by Jouni Malinen
parent 5197f0335c
commit f119d66942
2 changed files with 18 additions and 10 deletions

View file

@ -317,11 +317,15 @@ eap_pwd_perform_commit_exchange(struct eap_sm *sm, struct eap_pwd_data *data,
goto fin;
}
BN_rand_range(data->private_value, data->grp->order);
BN_rand_range(mask, data->grp->order);
BN_add(data->my_scalar, data->private_value, mask);
if (BN_rand_range(data->private_value, data->grp->order) != 1 ||
BN_rand_range(mask, data->grp->order) != 1 ||
BN_add(data->my_scalar, data->private_value, mask) != 1 ||
BN_mod(data->my_scalar, data->my_scalar, data->grp->order,
data->bnctx);
data->bnctx) != 1) {
wpa_printf(MSG_INFO,
"EAP-pwd (peer): unable to get randomness");
goto fin;
}
if (!EC_POINT_mul(data->grp->group, data->my_element, NULL,
data->grp->pwe, mask, data->bnctx)) {

View file

@ -210,11 +210,15 @@ static void eap_pwd_build_commit_req(struct eap_sm *sm,
goto fin;
}
BN_rand_range(data->private_value, data->grp->order);
BN_rand_range(mask, data->grp->order);
BN_add(data->my_scalar, data->private_value, mask);
if (BN_rand_range(data->private_value, data->grp->order) != 1 ||
BN_rand_range(mask, data->grp->order) != 1 ||
BN_add(data->my_scalar, data->private_value, mask) != 1 ||
BN_mod(data->my_scalar, data->my_scalar, data->grp->order,
data->bnctx);
data->bnctx) != 1) {
wpa_printf(MSG_INFO,
"EAP-pwd (server): unable to get randomness");
goto fin;
}
if (!EC_POINT_mul(data->grp->group, data->my_element, NULL,
data->grp->pwe, mask, data->bnctx)) {