Does hostapd not support setting acl rules for each bss?

[Ming Kuang]

Hello, everyone,

I have two bss on the same radio and I'm trying to configure allow and
deny list for each bss.

I have written the following configuration for hostapd (cropped):
interface=wlan0
driver=nl80211
...
accept_mac_file=/data/hostapd.accept
deny_mac_file=/data/hostapd.deny
macaddr_acl=0
...
bss=wlan0_0
accept_mac_file=/data/hostapd_0.accept
deny_mac_file=/data/hostapd_0.deny
...

However the acl rules on the second bss wlan0_0 does not take effect now.

I checked with the iwpriv command and found that the acl rules were
indeed not configured into the driver, so I started looking at the logic
in hostapd.

We use hostapd_set_acl to configure acl rules to the driver, however the
function seems to always use the rules recorded in bss[0]

int hostapd_set_acl(struct hostapd_data *hapd)
{
	struct hostapd_config *conf = hapd->iconf;
...
	if (conf->bss[0]->macaddr_acl == DENY_UNLESS_ACCEPTED) {
		accept_acl = 1;
		err = hostapd_set_acl_list(hapd, conf->bss[0]->accept_mac,
					   conf->bss[0]->num_accept_mac,
					   accept_acl);
...
	} else if (conf->bss[0]->macaddr_acl == ACCEPT_UNLESS_DENIED) {
		accept_acl = 0;
		err = hostapd_set_acl_list(hapd, conf->bss[0]->deny_mac,
					   conf->bss[0]->num_deny_mac,
					   accept_acl);
...
	}
	return err;
}

By adding logs to the DENY_ACL SHOW process, I confirmed that my
configurations were correctly parsed into each bss's hapd struct.

So why does hostapd only use the bss[0]'s acl configuration?
What happens if I modify the hostapd_set_acl function to use its
incoming parameter hapd's configuration hapd->conf instead of
hapd->iconf->bss[0]?

I'm not particularly familiar with hostapd, so if anyone can
enlighten me it would be greatly appreciated!