root@OpenWrt:~# cat /var/run/hostapd-ath0.conf
driver=madwifi
interface=ath0
bridge=br-lan
ssid=sanitized
debug=1
wpa=2
wpa_pairwise=CCMP
wpa_passphrase=sanitized-63-hex-digits
root@OpenWrt:~# 

root@OpenWrt:~# hostapd /var/run/hostapd-ath0.conf
Configuration file: /var/run/hostapd-ath0.conf
Configure bridge br-lan for EAPOL traffic.
madwifi_set_privacy: enabled=0
BSS count 1, BSSID mask ff:ff:ff:ff:ff:ff (0 bits)
madwifi_del_key: addr=00:00:00:00:00:00 key_idx=0
madwifi_del_key: addr=00:00:00:00:00:00 key_idx=1
madwifi_del_key: addr=00:00:00:00:00:00 key_idx=2
madwifi_del_key: addr=00:00:00:00:00:00 key_idx=3
Using interface ath0 with hwaddr 00:0b:6b:sa:ns:lf and ssid 'sanitized'
madwifi_configure_wpa: group key cipher=3
madwifi_configure_wpa: pairwise key ciphers=0x8
madwifi_configure_wpa: key management algorithms=0x2
madwifi_configure_wpa: rsn capabilities=0x0
madwifi_configure_wpa: enable WPA=0x2
madwifi_set_privacy: enabled=0
madwifi_set_key: alg=CCMP addr=00:00:00:00:00:00 key_idx=1
madwifi_set_privacy: enabled=1