mirror of
https://github.com/vanhoefm/fragattacks.git
synced 2025-02-19 10:33:05 -05:00
ba4f3224ae
The documentation in the hostapd.conf file says that the dynamic_vlan variable is used to control whether VLAN assignments are accepted from a RADIUS server. The implication seems to be that a static VLAN assignment will come from the accept_mac_file if dynamic_vlan is set to 0, and a dynamic assignment will come from the RADIUS server if dynamic_vlan is set to 1. Instead, I'm seeing that the static settings from the accept_mac_file are ignored if dynamic_vlan is set to 0, but used if dynamic_vlan is set to 1. If dynamic_vlan is set to 1 and the RADIUS server does not provide a VLAN, then the accept_mac_file assignment is overridden and the STA is assigned to the default non-VLANed interface. If my understanding of the expected behavior is correct, then I believe the problem is in ap_sta_set_vlan(). That routine checks the dynamic_vlan setting, but has no way of determining whether the incoming vlan_desc is static (i.e., from accept_mac_file) or dynamic (i.e., from a RADIUS server). I've attached a patch that gets hostapd working as I believe it's meant to, and updates the documentation to make the implicit behavior explicit. The functional changes are: - hostapd_allowed_address() will always extract the vlan_id from the accept_macs file. It will not update the vlan_id from the RADIUS cache if dynamic_vlan is DISABLED. - hostapd_acl_recv_radius() will not update the cached vlan_id if dynamic_vlan is DISABLED. - ieee802_1x_receive_auth() will not update the vlan_id if dynamic_vlan is DISABLED. More cosmetic: Most of the delta is just moving code out of ieee802_1x_receive_auth() into a new ieee802_1x_update_vlan() routine. While I initially did this because the new DISABLED check introduced excessive indentation, it has the added advantage of eliminating the vlan_description allocation and os_memset() call for all DYNAMIC_VLAN_DISABLED configs. I've done a couple rounds of review offline with Michael Braun (who has done much of the work in this part of the code) and incorporated his feedback. If dynamic_vlan=0 (disabled), vlan assignments will be managed using the local accept_mac_file ACL file, even if a RADIUS server is being used for user authentication. This allows us to manage users and devices independently. Signed-off-by: Nils Nieuwejaar <nils.nieuwejaar@gmail.com>