From 9c06f0f6aed26c1628acaa74df0232dd7b345e9a Mon Sep 17 00:00:00 2001 From: Venkateswara Naralasetty Date: Wed, 5 Dec 2018 11:23:51 +0100 Subject: [PATCH] hostapd: Add Multi-AP protocol support The purpose of Multi-AP specification is to enable inter-operability across Wi-Fi access points (APs) from different vendors. This patch introduces one new configuration parameter 'multi_ap' to enable Multi-AP functionality and to configure the BSS as a backhaul and/or fronthaul BSS. Advertise vendor specific Multi-AP capabilities in (Re)Association Response frame, if Multi-AP functionality is enabled through the configuration parameter. A backhaul AP must support receiving both 3addr and 4addr frames from a backhaul STA, so create a VLAN for it just like is done for WDS, i.e., by calling hostapd_set_wds_sta(). Since Multi-AP requires WPA2 (never WEP), we can safely call hostapd_set_wds_encryption() as well and we can reuse the entire WDS condition. To parse the Multi-AP Extension subelement, we use get_ie(): even though that function is meant for parsing IEs, it works for subelements. Signed-off-by: Venkateswara Naralasetty Signed-off-by: Jouni Malinen Signed-off-by: Arnout Vandecappelle (Essensium/Mind) --- hostapd/config_file.c | 10 +++++ hostapd/hostapd.conf | 7 ++++ src/ap/ap_config.h | 4 ++ src/ap/ieee802_11.c | 77 +++++++++++++++++++++++++++++++++- src/ap/sta_info.c | 2 +- src/ap/sta_info.h | 1 + src/common/ieee802_11_common.c | 24 +++++++++++ src/common/ieee802_11_common.h | 4 ++ src/common/ieee802_11_defs.h | 7 ++++ 9 files changed, 134 insertions(+), 2 deletions(-) --- a/hostapd/config_file.c +++ b/hostapd/config_file.c @@ -4115,6 +4115,16 @@ static int hostapd_config_fill(struct ho } else if (os_strcmp(buf, "coloc_intf_reporting") == 0) { bss->coloc_intf_reporting = atoi(pos); #endif /* CONFIG_OWE */ + } else if (os_strcmp(buf, "multi_ap") == 0) { + int val = atoi(pos); + + if (val < 0 || val > 3) { + wpa_printf(MSG_ERROR, "Line %d: Invalid multi_ap '%s'", + line, buf); + return -1; + } + + bss->multi_ap = val; } else { wpa_printf(MSG_ERROR, "Line %d: unknown configuration item '%s'", --- a/hostapd/hostapd.conf +++ b/hostapd/hostapd.conf @@ -438,6 +438,13 @@ wmm_ac_vo_txop_limit=47 wmm_ac_vo_acm=0 # Note: for IEEE 802.11b mode: cWmin=3 cWmax=4 burst=102 +# Enable Multi-AP functionality +# 0 = disabled (default) +# 1 = AP support backhaul BSS +# 2 = AP support fronthaul BSS +# 3 = AP supports both backhaul BSS and fronthaul BSS +#multi_ap=0 + # Static WEP key configuration # # The key number to use when transmitting. --- a/src/ap/ap_config.h +++ b/src/ap/ap_config.h @@ -688,6 +688,10 @@ struct hostapd_bss_config { #endif /* CONFIG_OWE */ int coloc_intf_reporting; + +#define BACKHAUL_BSS 1 +#define FRONTHAUL_BSS 2 + int multi_ap; /* bitmap of BACKHAUL_BSS, FRONTHAUL_BSS */ }; /** --- a/src/ap/ieee802_11.c +++ b/src/ap/ieee802_11.c @@ -62,6 +62,22 @@ prepare_auth_resp_fils(struct hostapd_da int *is_pub); #endif /* CONFIG_FILS */ + +u8 * hostapd_eid_multi_ap(struct hostapd_data *hapd, u8 *eid) +{ + u8 multi_ap_val = 0; + + if (!hapd->conf->multi_ap) + return eid; + if (hapd->conf->multi_ap & BACKHAUL_BSS) + multi_ap_val |= MULTI_AP_BACKHAUL_BSS; + if (hapd->conf->multi_ap & FRONTHAUL_BSS) + multi_ap_val |= MULTI_AP_FRONTHAUL_BSS; + + return eid + add_multi_ap_ie(eid, 9, multi_ap_val); +} + + u8 * hostapd_eid_supp_rates(struct hostapd_data *hapd, u8 *eid) { u8 *pos = eid; @@ -2210,6 +2226,57 @@ static u16 check_wmm(struct hostapd_data return WLAN_STATUS_SUCCESS; } +static u16 check_multi_ap(struct hostapd_data *hapd, struct sta_info *sta, + const u8 *multi_ap_ie, size_t multi_ap_len) +{ + u8 multi_ap_value = 0; + + sta->flags &= ~WLAN_STA_MULTI_AP; + + if (!hapd->conf->multi_ap) + return WLAN_STATUS_SUCCESS; + + if (multi_ap_ie) { + const u8 *multi_ap_subelem; + + multi_ap_subelem = get_ie(multi_ap_ie + 4, + multi_ap_len - 4, + MULTI_AP_SUB_ELEM_TYPE); + if (multi_ap_subelem && multi_ap_subelem[1] == 1) { + multi_ap_value = multi_ap_subelem[2]; + } else { + hostapd_logger(hapd, sta->addr, + HOSTAPD_MODULE_IEEE80211, + HOSTAPD_LEVEL_INFO, + "Multi-AP IE has missing or invalid Multi-AP subelement"); + return WLAN_STATUS_INVALID_IE; + } + } + + if (multi_ap_value == MULTI_AP_BACKHAUL_STA) + sta->flags |= WLAN_STA_MULTI_AP; + + if ((hapd->conf->multi_ap & BACKHAUL_BSS) && + multi_ap_value == MULTI_AP_BACKHAUL_STA) + return WLAN_STATUS_SUCCESS; + + if (hapd->conf->multi_ap & FRONTHAUL_BSS) { + if (multi_ap_value == MULTI_AP_BACKHAUL_STA) { + hostapd_logger(hapd, sta->addr, + HOSTAPD_MODULE_IEEE80211, + HOSTAPD_LEVEL_INFO, + "Backhaul STA tries to associate with fronthaul-only BSS"); + return WLAN_STATUS_ASSOC_DENIED_UNSPEC; + } + return WLAN_STATUS_SUCCESS; + } + + hostapd_logger(hapd, sta->addr, HOSTAPD_MODULE_IEEE80211, + HOSTAPD_LEVEL_INFO, + "Non-Multi-AP STA tries to associate with backhaul-only BSS"); + return WLAN_STATUS_ASSOC_DENIED_UNSPEC; +} + static u16 copy_supp_rates(struct hostapd_data *hapd, struct sta_info *sta, struct ieee802_11_elems *elems) @@ -2466,6 +2533,11 @@ static u16 check_assoc_ies(struct hostap resp = copy_supp_rates(hapd, sta, &elems); if (resp != WLAN_STATUS_SUCCESS) return resp; + + resp = check_multi_ap(hapd, sta, elems.multi_ap, elems.multi_ap_len); + if (resp != WLAN_STATUS_SUCCESS) + return resp; + #ifdef CONFIG_IEEE80211N resp = copy_sta_ht_capab(hapd, sta, elems.ht_capabilities); if (resp != WLAN_STATUS_SUCCESS) @@ -2996,6 +3068,9 @@ static u16 send_assoc_resp(struct hostap } #endif /* CONFIG_WPS */ + if (sta && (sta->flags & WLAN_STA_MULTI_AP)) + p = hostapd_eid_multi_ap(hapd, p); + #ifdef CONFIG_P2P if (sta && sta->p2p_ie && hapd->p2p_group) { struct wpabuf *p2p_resp_ie; @@ -4236,7 +4311,7 @@ static void handle_assoc_cb(struct hosta sta->flags |= WLAN_STA_WDS; } - if (sta->flags & WLAN_STA_WDS) { + if (sta->flags & (WLAN_STA_WDS | WLAN_STA_MULTI_AP)) { int ret; char ifname_wds[IFNAMSIZ + 1]; --- a/src/ap/sta_info.c +++ b/src/ap/sta_info.c @@ -166,7 +166,7 @@ void ap_free_sta(struct hostapd_data *ha /* just in case */ ap_sta_set_authorized(hapd, sta, 0); - if (sta->flags & WLAN_STA_WDS) + if (sta->flags & (WLAN_STA_WDS | WLAN_STA_MULTI_AP)) hostapd_set_wds_sta(hapd, NULL, sta->addr, sta->aid, 0); if (sta->ipaddr) --- a/src/ap/sta_info.h +++ b/src/ap/sta_info.h @@ -36,6 +36,7 @@ #define WLAN_STA_VHT_OPMODE_ENABLED BIT(20) #define WLAN_STA_VENDOR_VHT BIT(21) #define WLAN_STA_PENDING_FILS_ERP BIT(22) +#define WLAN_STA_MULTI_AP BIT(23) #define WLAN_STA_PENDING_DISASSOC_CB BIT(29) #define WLAN_STA_PENDING_DEAUTH_CB BIT(30) #define WLAN_STA_NONERP BIT(31) --- a/src/common/ieee802_11_common.c +++ b/src/common/ieee802_11_common.c @@ -126,6 +126,10 @@ static int ieee802_11_parse_vendor_speci elems->roaming_cons_sel = pos; elems->roaming_cons_sel_len = elen; break; + case MULTI_AP_OUI_TYPE: + elems->multi_ap = pos; + elems->multi_ap_len = elen; + break; default: wpa_printf(MSG_MSGDUMP, "Unknown WFA " "information element ignored " @@ -1519,6 +1523,26 @@ size_t mbo_add_ie(u8 *buf, size_t len, c } +size_t add_multi_ap_ie(u8 *buf, size_t len, u8 value) +{ + u8 *pos = buf; + + if (len < 9) + return 0; + + *pos++ = WLAN_EID_VENDOR_SPECIFIC; + *pos++ = 7; /* len */ + WPA_PUT_BE24(pos, OUI_WFA); + pos += 3; + *pos++ = MULTI_AP_OUI_TYPE; + *pos++ = MULTI_AP_SUB_ELEM_TYPE; + *pos++ = 1; /* len */ + *pos++ = value; + + return pos - buf; +} + + static const struct country_op_class us_op_class[] = { { 1, 115 }, { 2, 118 }, --- a/src/common/ieee802_11_common.h +++ b/src/common/ieee802_11_common.h @@ -84,6 +84,7 @@ struct ieee802_11_elems { const u8 *power_capab; const u8 *roaming_cons_sel; const u8 *password_id; + const u8 *multi_ap; u8 ssid_len; u8 supp_rates_len; @@ -130,6 +131,7 @@ struct ieee802_11_elems { u8 power_capab_len; u8 roaming_cons_sel_len; u8 password_id_len; + u8 multi_ap_len; struct mb_ies_info mb_ies; }; @@ -189,6 +191,8 @@ const u8 * get_ie_ext(const u8 *ies, siz size_t mbo_add_ie(u8 *buf, size_t len, const u8 *attr, size_t attr_len); +size_t add_multi_ap_ie(u8 *buf, size_t len, u8 value); + struct country_op_class { u8 country_op_class; u8 global_op_class; --- a/src/common/ieee802_11_defs.h +++ b/src/common/ieee802_11_defs.h @@ -1210,6 +1210,13 @@ struct ieee80211_ampe_ie { #define MBO_OUI_TYPE 22 #define OWE_IE_VENDOR_TYPE 0x506f9a1c #define OWE_OUI_TYPE 28 +#define MULTI_AP_OUI_TYPE 0x1B + +#define MULTI_AP_SUB_ELEM_TYPE 0x06 +#define MULTI_AP_TEAR_DOWN BIT(4) +#define MULTI_AP_FRONTHAUL_BSS BIT(5) +#define MULTI_AP_BACKHAUL_BSS BIT(6) +#define MULTI_AP_BACKHAUL_STA BIT(7) #define WMM_OUI_TYPE 2 #define WMM_OUI_SUBTYPE_INFORMATION_ELEMENT 0