From 190650c71454d2076d5103d0245f4c40b1fed5ff Mon Sep 17 00:00:00 2001 From: Cy Schubert Date: Thu, 19 Jul 2018 14:35:27 +0000 Subject: [PATCH] Import upline hostapd-avoid-key-reinstallation security patch. Obtained from: https://w1.fi/security/2017-1/\ rebased-v2.6-0001-hostapd-Avoid-key-\ reinstallation-in-FT-handshake.patch --- src/ap/ieee802_11.c | 16 +++++++++++++--- src/ap/wpa_auth.c | 11 +++++++++++ src/ap/wpa_auth.h | 3 ++- src/ap/wpa_auth_ft.c | 10 ++++++++++ src/ap/wpa_auth_i.h | 1 + 5 files changed, 37 insertions(+), 4 deletions(-) diff --git a/src/ap/ieee802_11.c b/src/ap/ieee802_11.c index 4e04169c73e6..333035fe7703 100644 --- a/src/ap/ieee802_11.c +++ b/src/ap/ieee802_11.c @@ -1841,6 +1841,7 @@ static int add_associated_sta(struct hostapd_data *hapd, { struct ieee80211_ht_capabilities ht_cap; struct ieee80211_vht_capabilities vht_cap; + int set = 1; /* * Remove the STA entry to ensure the STA PS state gets cleared and @@ -1848,9 +1849,18 @@ static int add_associated_sta(struct hostapd_data *hapd, * FT-over-the-DS, where a station re-associates back to the same AP but * skips the authentication flow, or if working with a driver that * does not support full AP client state. + * + * Skip this if the STA has already completed FT reassociation and the + * TK has been configured since the TX/RX PN must not be reset to 0 for + * the same key. */ - if (!sta->added_unassoc) + if (!sta->added_unassoc && + (!(sta->flags & WLAN_STA_AUTHORIZED) || + !wpa_auth_sta_ft_tk_already_set(sta->wpa_sm))) { hostapd_drv_sta_remove(hapd, sta->addr); + wpa_auth_sm_event(sta->wpa_sm, WPA_DRV_STA_REMOVED); + set = 0; + } #ifdef CONFIG_IEEE80211N if (sta->flags & WLAN_STA_HT) @@ -1873,11 +1883,11 @@ static int add_associated_sta(struct hostapd_data *hapd, sta->flags & WLAN_STA_VHT ? &vht_cap : NULL, sta->flags | WLAN_STA_ASSOC, sta->qosinfo, sta->vht_opmode, sta->p2p_ie ? 1 : 0, - sta->added_unassoc)) { + set)) { hostapd_logger(hapd, sta->addr, HOSTAPD_MODULE_IEEE80211, HOSTAPD_LEVEL_NOTICE, "Could not %s STA to kernel driver", - sta->added_unassoc ? "set" : "add"); + set ? "set" : "add"); if (sta->added_unassoc) { hostapd_drv_sta_remove(hapd, sta->addr); diff --git a/src/ap/wpa_auth.c b/src/ap/wpa_auth.c index 358708648977..707971d06f21 100644 --- a/src/ap/wpa_auth.c +++ b/src/ap/wpa_auth.c @@ -1745,6 +1745,9 @@ int wpa_auth_sm_event(struct wpa_state_machine *sm, enum wpa_event event) #else /* CONFIG_IEEE80211R */ break; #endif /* CONFIG_IEEE80211R */ + case WPA_DRV_STA_REMOVED: + sm->tk_already_set = FALSE; + return 0; } #ifdef CONFIG_IEEE80211R @@ -3250,6 +3253,14 @@ int wpa_auth_sta_wpa_version(struct wpa_state_machine *sm) } +int wpa_auth_sta_ft_tk_already_set(struct wpa_state_machine *sm) +{ + if (!sm || !wpa_key_mgmt_ft(sm->wpa_key_mgmt)) + return 0; + return sm->tk_already_set; +} + + int wpa_auth_sta_clear_pmksa(struct wpa_state_machine *sm, struct rsn_pmksa_cache_entry *entry) { diff --git a/src/ap/wpa_auth.h b/src/ap/wpa_auth.h index 0de8d976e3f9..97461b029d24 100644 --- a/src/ap/wpa_auth.h +++ b/src/ap/wpa_auth.h @@ -267,7 +267,7 @@ void wpa_receive(struct wpa_authenticator *wpa_auth, u8 *data, size_t data_len); enum wpa_event { WPA_AUTH, WPA_ASSOC, WPA_DISASSOC, WPA_DEAUTH, WPA_REAUTH, - WPA_REAUTH_EAPOL, WPA_ASSOC_FT + WPA_REAUTH_EAPOL, WPA_ASSOC_FT, WPA_DRV_STA_REMOVED }; void wpa_remove_ptk(struct wpa_state_machine *sm); int wpa_auth_sm_event(struct wpa_state_machine *sm, enum wpa_event event); @@ -280,6 +280,7 @@ int wpa_auth_pairwise_set(struct wpa_state_machine *sm); int wpa_auth_get_pairwise(struct wpa_state_machine *sm); int wpa_auth_sta_key_mgmt(struct wpa_state_machine *sm); int wpa_auth_sta_wpa_version(struct wpa_state_machine *sm); +int wpa_auth_sta_ft_tk_already_set(struct wpa_state_machine *sm); int wpa_auth_sta_clear_pmksa(struct wpa_state_machine *sm, struct rsn_pmksa_cache_entry *entry); struct rsn_pmksa_cache_entry * diff --git a/src/ap/wpa_auth_ft.c b/src/ap/wpa_auth_ft.c index 42242a54a2cb..e63b99ad2034 100644 --- a/src/ap/wpa_auth_ft.c +++ b/src/ap/wpa_auth_ft.c @@ -780,6 +780,14 @@ void wpa_ft_install_ptk(struct wpa_state_machine *sm) return; } + if (sm->tk_already_set) { + /* Must avoid TK reconfiguration to prevent clearing of TX/RX + * PN in the driver */ + wpa_printf(MSG_DEBUG, + "FT: Do not re-install same PTK to the driver"); + return; + } + /* FIX: add STA entry to kernel/driver here? The set_key will fail * most likely without this.. At the moment, STA entry is added only * after association has been completed. This function will be called @@ -792,6 +800,7 @@ void wpa_ft_install_ptk(struct wpa_state_machine *sm) /* FIX: MLME-SetProtection.Request(TA, Tx_Rx) */ sm->pairwise_set = TRUE; + sm->tk_already_set = TRUE; } @@ -898,6 +907,7 @@ static int wpa_ft_process_auth_req(struct wpa_state_machine *sm, sm->pairwise = pairwise; sm->PTK_valid = TRUE; + sm->tk_already_set = FALSE; wpa_ft_install_ptk(sm); buflen = 2 + sizeof(struct rsn_mdie) + 2 + sizeof(struct rsn_ftie) + diff --git a/src/ap/wpa_auth_i.h b/src/ap/wpa_auth_i.h index 72b7eb37a3a7..7fd8f05fa8ff 100644 --- a/src/ap/wpa_auth_i.h +++ b/src/ap/wpa_auth_i.h @@ -65,6 +65,7 @@ struct wpa_state_machine { struct wpa_ptk PTK; Boolean PTK_valid; Boolean pairwise_set; + Boolean tk_already_set; int keycount; Boolean Pair; struct wpa_key_replay_counter {