| Message ID | 20231213140412.326465-6-andrei.otcheretianski@intel.com |
|---|---|
| State | Accepted |
| Headers | show |
| Series | [1/8] AP: WNM: Use correct address when configured as AP MLD | expand |
On Wed, Dec 13, 2023 at 04:04:10PM +0200, Andrei Otcheretianski wrote: > Based on Draft P802.11be_D3.0, when a station is non-AP MLD with more > then one link and "Link Removal Imminent" is set, the "Disassociation > Imminent" and "BSS Termination Included" can be ignored, as the station > will not be disassociated. That is not what the standard says.. Those two bits are not being "ignored". In particular, there is a specific meaning for BSS Termination Included value 0 which is clearly not supposed to be ignored.. > diff --git a/wpa_supplicant/wnm_sta.c b/wpa_supplicant/wnm_sta.c > + /* > + * Based on Draft P802.11be_D3.0, when a station is non-AP MLD with more > + * then one link and "link removal imminent" is set, the below flags can > + * be ignored, as the station will not be disassociated. > + */ > + if ((wpa_s->valid_links & (wpa_s->valid_links - 1)) != 0 && > + wpa_s->wnm_mode & WNM_BSS_TM_REQ_LINK_REMOVAL_IMMINENT && > + (wpa_s->wnm_mode & WNM_BSS_TM_REQ_DISASSOC_IMMINENT || > + wpa_s->wnm_mode & WNM_BSS_TM_REQ_BSS_TERMINATION_INCLUDED)) { > + wpa_printf(MSG_INFO, > + "WNM: BTM request for single MLO link. ignore"); > + return; > + } So those conditions are incorrect since the link removal case applies only if BSS Termination Included is set to 1. Furthermore, I did not find any justification from the standard to ignore the BTM request itself, i.e., this request still needs a response. I fixed these and the test in the following patch to match the functionality. In addition, patch 8/8 broke functionality since it did not make sure wpa_s->wnm_mode is cleared for new associations/disassociations and the old value was incorrectly used for cases where there had been no disassociation imminent indication. I applied all eight patches with cleanup and fixes.
diff --git a/src/common/ieee802_11_defs.h b/src/common/ieee802_11_defs.h index cd33f6a8f5..2d865e639c 100644 --- a/src/common/ieee802_11_defs.h +++ b/src/common/ieee802_11_defs.h @@ -1880,11 +1880,12 @@ enum wnm_action { }; /* IEEE 802.11v - BSS Transition Management Request - Request Mode */ -#define WNM_BSS_TM_REQ_PREF_CAND_LIST_INCLUDED BIT(0) -#define WNM_BSS_TM_REQ_ABRIDGED BIT(1) -#define WNM_BSS_TM_REQ_DISASSOC_IMMINENT BIT(2) -#define WNM_BSS_TM_REQ_BSS_TERMINATION_INCLUDED BIT(3) -#define WNM_BSS_TM_REQ_ESS_DISASSOC_IMMINENT BIT(4) +#define WNM_BSS_TM_REQ_PREF_CAND_LIST_INCLUDED BIT(0) +#define WNM_BSS_TM_REQ_ABRIDGED BIT(1) +#define WNM_BSS_TM_REQ_DISASSOC_IMMINENT BIT(2) +#define WNM_BSS_TM_REQ_BSS_TERMINATION_INCLUDED BIT(3) +#define WNM_BSS_TM_REQ_ESS_DISASSOC_IMMINENT BIT(4) +#define WNM_BSS_TM_REQ_LINK_REMOVAL_IMMINENT BIT(5) /* IEEE Std 802.11-2012 - Table 8-253 */ enum bss_trans_mgmt_status_code { diff --git a/wpa_supplicant/wnm_sta.c b/wpa_supplicant/wnm_sta.c index 493821b37f..bcbd8c04c9 100644 --- a/wpa_supplicant/wnm_sta.c +++ b/wpa_supplicant/wnm_sta.c @@ -1479,6 +1479,20 @@ static void ieee802_11_rx_bss_trans_mgmt_req(struct wpa_supplicant *wpa_s, } #endif /* CONFIG_MBO && CONFIG_TESTING_OPTIONS */ + /* + * Based on Draft P802.11be_D3.0, when a station is non-AP MLD with more + * then one link and "link removal imminent" is set, the below flags can + * be ignored, as the station will not be disassociated. + */ + if ((wpa_s->valid_links & (wpa_s->valid_links - 1)) != 0 && + wpa_s->wnm_mode & WNM_BSS_TM_REQ_LINK_REMOVAL_IMMINENT && + (wpa_s->wnm_mode & WNM_BSS_TM_REQ_DISASSOC_IMMINENT || + wpa_s->wnm_mode & WNM_BSS_TM_REQ_BSS_TERMINATION_INCLUDED)) { + wpa_printf(MSG_INFO, + "WNM: BTM request for single MLO link. ignore"); + return; + } + pos += 5; if (wpa_s->wnm_mode & WNM_BSS_TM_REQ_BSS_TERMINATION_INCLUDED) {