The WPA2 four-way handshake protocol is vulnerable to replay attacks which can result in unauthenticated clients gaining access to the network. Backport a number of patches from upstream to fix this. CVE: CVE-2017-13077 CVE: CVE-2017-13078 CVE: CVE-2017-13079 CVE: CVE-2017-13080 CVE: CVE-2017-13081 CVE: CVE-2017-13082 CVE: CVE-2017-13086 CVE: CVE-2017-13087 CVE: CVE-2017-13088 Upstream-Status: Backport Signed-off-by: Ross Burton From cf4cab804c7afd5c45505528a8d16e46163243a2 Mon Sep 17 00:00:00 2001 From: Mathy Vanhoef Date: Fri, 14 Jul 2017 15:15:35 +0200 Subject: [PATCH 1/8] hostapd: Avoid key reinstallation in FT handshake Do not reinstall TK to the driver during Reassociation Response frame processing if the first attempt of setting the TK succeeded. This avoids issues related to clearing the TX/RX PN that could result in reusing same PN values for transmitted frames (e.g., due to CCM nonce reuse and also hitting replay protection on the receiver) and accepting replayed frames on RX side. This issue was introduced by the commit 0e84c25434e6a1f283c7b4e62e483729085b78d2 ('FT: Fix PTK configuration in authenticator') which allowed wpa_ft_install_ptk() to be called multiple times with the same PTK. While the second configuration attempt is needed with some drivers, it must be done only if the first attempt failed. Signed-off-by: Mathy Vanhoef --- 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 4e04169..333035f 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 3587086..707971d 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 0de8d97..97461b0 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 42242a5..e63b99a 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 72b7eb3..7fd8f05 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 { -- 2.7.4 From 927f891007c402fefd1ff384645b3f07597c3ede Mon Sep 17 00:00:00 2001 From: Mathy Vanhoef Date: Wed, 12 Jul 2017 16:03:24 +0200 Subject: [PATCH 2/8] Prevent reinstallation of an already in-use group key Track the current GTK and IGTK that is in use and when receiving a (possibly retransmitted) Group Message 1 or WNM-Sleep Mode Response, do not install the given key if it is already in use. This prevents an attacker from trying to trick the client into resetting or lowering the sequence counter associated to the group key. Signed-off-by: Mathy Vanhoef --- src/common/wpa_common.h | 11 +++++ src/rsn_supp/wpa.c | 116 ++++++++++++++++++++++++++++++------------------ src/rsn_supp/wpa_i.h | 4 ++ 3 files changed, 87 insertions(+), 44 deletions(-) diff --git a/src/common/wpa_common.h b/src/common/wpa_common.h index af1d0f0..d200285 100644 --- a/src/common/wpa_common.h +++ b/src/common/wpa_common.h @@ -217,6 +217,17 @@ struct wpa_ptk { size_t tk_len; }; +struct wpa_gtk { + u8 gtk[WPA_GTK_MAX_LEN]; + size_t gtk_len; +}; + +#ifdef CONFIG_IEEE80211W +struct wpa_igtk { + u8 igtk[WPA_IGTK_MAX_LEN]; + size_t igtk_len; +}; +#endif /* CONFIG_IEEE80211W */ /* WPA IE version 1 * 00-50-f2:1 (OUI:OUI type) diff --git a/src/rsn_supp/wpa.c b/src/rsn_supp/wpa.c index 3c47879..95bd7be 100644 --- a/src/rsn_supp/wpa.c +++ b/src/rsn_supp/wpa.c @@ -714,6 +714,15 @@ static int wpa_supplicant_install_gtk(struct wpa_sm *sm, const u8 *_gtk = gd->gtk; u8 gtk_buf[32]; + /* Detect possible key reinstallation */ + if (sm->gtk.gtk_len == (size_t) gd->gtk_len && + os_memcmp(sm->gtk.gtk, gd->gtk, sm->gtk.gtk_len) == 0) { + wpa_dbg(sm->ctx->msg_ctx, MSG_DEBUG, + "WPA: Not reinstalling already in-use GTK to the driver (keyidx=%d tx=%d len=%d)", + gd->keyidx, gd->tx, gd->gtk_len); + return 0; + } + wpa_hexdump_key(MSG_DEBUG, "WPA: Group Key", gd->gtk, gd->gtk_len); wpa_dbg(sm->ctx->msg_ctx, MSG_DEBUG, "WPA: Installing GTK to the driver (keyidx=%d tx=%d len=%d)", @@ -748,6 +757,9 @@ static int wpa_supplicant_install_gtk(struct wpa_sm *sm, } os_memset(gtk_buf, 0, sizeof(gtk_buf)); + sm->gtk.gtk_len = gd->gtk_len; + os_memcpy(sm->gtk.gtk, gd->gtk, sm->gtk.gtk_len); + return 0; } @@ -854,6 +866,48 @@ static int wpa_supplicant_pairwise_gtk(struct wpa_sm *sm, } +#ifdef CONFIG_IEEE80211W +static int wpa_supplicant_install_igtk(struct wpa_sm *sm, + const struct wpa_igtk_kde *igtk) +{ + size_t len = wpa_cipher_key_len(sm->mgmt_group_cipher); + u16 keyidx = WPA_GET_LE16(igtk->keyid); + + /* Detect possible key reinstallation */ + if (sm->igtk.igtk_len == len && + os_memcmp(sm->igtk.igtk, igtk->igtk, sm->igtk.igtk_len) == 0) { + wpa_dbg(sm->ctx->msg_ctx, MSG_DEBUG, + "WPA: Not reinstalling already in-use IGTK to the driver (keyidx=%d)", + keyidx); + return 0; + } + + wpa_dbg(sm->ctx->msg_ctx, MSG_DEBUG, + "WPA: IGTK keyid %d pn %02x%02x%02x%02x%02x%02x", + keyidx, MAC2STR(igtk->pn)); + wpa_hexdump_key(MSG_DEBUG, "WPA: IGTK", igtk->igtk, len); + if (keyidx > 4095) { + wpa_msg(sm->ctx->msg_ctx, MSG_WARNING, + "WPA: Invalid IGTK KeyID %d", keyidx); + return -1; + } + if (wpa_sm_set_key(sm, wpa_cipher_to_alg(sm->mgmt_group_cipher), + broadcast_ether_addr, + keyidx, 0, igtk->pn, sizeof(igtk->pn), + igtk->igtk, len) < 0) { + wpa_msg(sm->ctx->msg_ctx, MSG_WARNING, + "WPA: Failed to configure IGTK to the driver"); + return -1; + } + + sm->igtk.igtk_len = len; + os_memcpy(sm->igtk.igtk, igtk->igtk, sm->igtk.igtk_len); + + return 0; +} +#endif /* CONFIG_IEEE80211W */ + + static int ieee80211w_set_keys(struct wpa_sm *sm, struct wpa_eapol_ie_parse *ie) { @@ -864,30 +918,14 @@ static int ieee80211w_set_keys(struct wpa_sm *sm, if (ie->igtk) { size_t len; const struct wpa_igtk_kde *igtk; - u16 keyidx; + len = wpa_cipher_key_len(sm->mgmt_group_cipher); if (ie->igtk_len != WPA_IGTK_KDE_PREFIX_LEN + len) return -1; + igtk = (const struct wpa_igtk_kde *) ie->igtk; - keyidx = WPA_GET_LE16(igtk->keyid); - wpa_dbg(sm->ctx->msg_ctx, MSG_DEBUG, "WPA: IGTK keyid %d " - "pn %02x%02x%02x%02x%02x%02x", - keyidx, MAC2STR(igtk->pn)); - wpa_hexdump_key(MSG_DEBUG, "WPA: IGTK", - igtk->igtk, len); - if (keyidx > 4095) { - wpa_msg(sm->ctx->msg_ctx, MSG_WARNING, - "WPA: Invalid IGTK KeyID %d", keyidx); - return -1; - } - if (wpa_sm_set_key(sm, wpa_cipher_to_alg(sm->mgmt_group_cipher), - broadcast_ether_addr, - keyidx, 0, igtk->pn, sizeof(igtk->pn), - igtk->igtk, len) < 0) { - wpa_msg(sm->ctx->msg_ctx, MSG_WARNING, - "WPA: Failed to configure IGTK to the driver"); + if (wpa_supplicant_install_igtk(sm, igtk) < 0) return -1; - } } return 0; @@ -2307,7 +2345,7 @@ void wpa_sm_deinit(struct wpa_sm *sm) */ void wpa_sm_notify_assoc(struct wpa_sm *sm, const u8 *bssid) { - int clear_ptk = 1; + int clear_keys = 1; if (sm == NULL) return; @@ -2333,11 +2371,11 @@ void wpa_sm_notify_assoc(struct wpa_sm *sm, const u8 *bssid) /* Prepare for the next transition */ wpa_ft_prepare_auth_request(sm, NULL); - clear_ptk = 0; + clear_keys = 0; } #endif /* CONFIG_IEEE80211R */ - if (clear_ptk) { + if (clear_keys) { /* * IEEE 802.11, 8.4.10: Delete PTK SA on (re)association if * this is not part of a Fast BSS Transition. @@ -2347,6 +2385,10 @@ void wpa_sm_notify_assoc(struct wpa_sm *sm, const u8 *bssid) os_memset(&sm->ptk, 0, sizeof(sm->ptk)); sm->tptk_set = 0; os_memset(&sm->tptk, 0, sizeof(sm->tptk)); + os_memset(&sm->gtk, 0, sizeof(sm->gtk)); +#ifdef CONFIG_IEEE80211W + os_memset(&sm->igtk, 0, sizeof(sm->igtk)); +#endif /* CONFIG_IEEE80211W */ } #ifdef CONFIG_TDLS @@ -2877,6 +2919,10 @@ void wpa_sm_drop_sa(struct wpa_sm *sm) os_memset(sm->pmk, 0, sizeof(sm->pmk)); os_memset(&sm->ptk, 0, sizeof(sm->ptk)); os_memset(&sm->tptk, 0, sizeof(sm->tptk)); + os_memset(&sm->gtk, 0, sizeof(sm->gtk)); +#ifdef CONFIG_IEEE80211W + os_memset(&sm->igtk, 0, sizeof(sm->igtk)); +#endif /* CONFIG_IEEE80211W */ #ifdef CONFIG_IEEE80211R os_memset(sm->xxkey, 0, sizeof(sm->xxkey)); os_memset(sm->pmk_r0, 0, sizeof(sm->pmk_r0)); @@ -2949,29 +2995,11 @@ int wpa_wnmsleep_install_key(struct wpa_sm *sm, u8 subelem_id, u8 *buf) os_memset(&gd, 0, sizeof(gd)); #ifdef CONFIG_IEEE80211W } else if (subelem_id == WNM_SLEEP_SUBELEM_IGTK) { - struct wpa_igtk_kde igd; - u16 keyidx; - - os_memset(&igd, 0, sizeof(igd)); - keylen = wpa_cipher_key_len(sm->mgmt_group_cipher); - os_memcpy(igd.keyid, buf + 2, 2); - os_memcpy(igd.pn, buf + 4, 6); - - keyidx = WPA_GET_LE16(igd.keyid); - os_memcpy(igd.igtk, buf + 10, keylen); - - wpa_hexdump_key(MSG_DEBUG, "Install IGTK (WNM SLEEP)", - igd.igtk, keylen); - if (wpa_sm_set_key(sm, wpa_cipher_to_alg(sm->mgmt_group_cipher), - broadcast_ether_addr, - keyidx, 0, igd.pn, sizeof(igd.pn), - igd.igtk, keylen) < 0) { - wpa_printf(MSG_DEBUG, "Failed to install the IGTK in " - "WNM mode"); - os_memset(&igd, 0, sizeof(igd)); + const struct wpa_igtk_kde *igtk; + + igtk = (const struct wpa_igtk_kde *) (buf + 2); + if (wpa_supplicant_install_igtk(sm, igtk) < 0) return -1; - } - os_memset(&igd, 0, sizeof(igd)); #endif /* CONFIG_IEEE80211W */ } else { wpa_printf(MSG_DEBUG, "Unknown element id"); diff --git a/src/rsn_supp/wpa_i.h b/src/rsn_supp/wpa_i.h index f653ba6..afc9e37 100644 --- a/src/rsn_supp/wpa_i.h +++ b/src/rsn_supp/wpa_i.h @@ -31,6 +31,10 @@ struct wpa_sm { u8 rx_replay_counter[WPA_REPLAY_COUNTER_LEN]; int rx_replay_counter_set; u8 request_counter[WPA_REPLAY_COUNTER_LEN]; + struct wpa_gtk gtk; +#ifdef CONFIG_IEEE80211W + struct wpa_igtk igtk; +#endif /* CONFIG_IEEE80211W */ struct eapol_sm *eapol; /* EAPOL state machine from upper level code */ -- 2.7.4 From 8280294e74846ea342389a0cd17215050fa5afe8 Mon Sep 17 00:00:00 2001 From: Jouni Malinen Date: Sun, 1 Oct 2017 12:12:24 +0300 Subject: [PATCH 3/8] Extend protection of GTK/IGTK reinstallation of WNM-Sleep Mode cases This extends the protection to track last configured GTK/IGTK value separately from EAPOL-Key frames and WNM-Sleep Mode frames to cover a corner case where these two different mechanisms may get used when the GTK/IGTK has changed and tracking a single value is not sufficient to detect a possible key reconfiguration. Signed-off-by: Jouni Malinen --- src/rsn_supp/wpa.c | 53 +++++++++++++++++++++++++++++++++++++--------------- src/rsn_supp/wpa_i.h | 2 ++ 2 files changed, 40 insertions(+), 15 deletions(-) diff --git a/src/rsn_supp/wpa.c b/src/rsn_supp/wpa.c index 95bd7be..7a2c68d 100644 --- a/src/rsn_supp/wpa.c +++ b/src/rsn_supp/wpa.c @@ -709,14 +709,17 @@ struct wpa_gtk_data { static int wpa_supplicant_install_gtk(struct wpa_sm *sm, const struct wpa_gtk_data *gd, - const u8 *key_rsc) + const u8 *key_rsc, int wnm_sleep) { const u8 *_gtk = gd->gtk; u8 gtk_buf[32]; /* Detect possible key reinstallation */ - if (sm->gtk.gtk_len == (size_t) gd->gtk_len && - os_memcmp(sm->gtk.gtk, gd->gtk, sm->gtk.gtk_len) == 0) { + if ((sm->gtk.gtk_len == (size_t) gd->gtk_len && + os_memcmp(sm->gtk.gtk, gd->gtk, sm->gtk.gtk_len) == 0) || + (sm->gtk_wnm_sleep.gtk_len == (size_t) gd->gtk_len && + os_memcmp(sm->gtk_wnm_sleep.gtk, gd->gtk, + sm->gtk_wnm_sleep.gtk_len) == 0)) { wpa_dbg(sm->ctx->msg_ctx, MSG_DEBUG, "WPA: Not reinstalling already in-use GTK to the driver (keyidx=%d tx=%d len=%d)", gd->keyidx, gd->tx, gd->gtk_len); @@ -757,8 +760,14 @@ static int wpa_supplicant_install_gtk(struct wpa_sm *sm, } os_memset(gtk_buf, 0, sizeof(gtk_buf)); - sm->gtk.gtk_len = gd->gtk_len; - os_memcpy(sm->gtk.gtk, gd->gtk, sm->gtk.gtk_len); + if (wnm_sleep) { + sm->gtk_wnm_sleep.gtk_len = gd->gtk_len; + os_memcpy(sm->gtk_wnm_sleep.gtk, gd->gtk, + sm->gtk_wnm_sleep.gtk_len); + } else { + sm->gtk.gtk_len = gd->gtk_len; + os_memcpy(sm->gtk.gtk, gd->gtk, sm->gtk.gtk_len); + } return 0; } @@ -852,7 +861,7 @@ static int wpa_supplicant_pairwise_gtk(struct wpa_sm *sm, (wpa_supplicant_check_group_cipher(sm, sm->group_cipher, gtk_len, gtk_len, &gd.key_rsc_len, &gd.alg) || - wpa_supplicant_install_gtk(sm, &gd, key_rsc))) { + wpa_supplicant_install_gtk(sm, &gd, key_rsc, 0))) { wpa_dbg(sm->ctx->msg_ctx, MSG_DEBUG, "RSN: Failed to install GTK"); os_memset(&gd, 0, sizeof(gd)); @@ -868,14 +877,18 @@ static int wpa_supplicant_pairwise_gtk(struct wpa_sm *sm, #ifdef CONFIG_IEEE80211W static int wpa_supplicant_install_igtk(struct wpa_sm *sm, - const struct wpa_igtk_kde *igtk) + const struct wpa_igtk_kde *igtk, + int wnm_sleep) { size_t len = wpa_cipher_key_len(sm->mgmt_group_cipher); u16 keyidx = WPA_GET_LE16(igtk->keyid); /* Detect possible key reinstallation */ - if (sm->igtk.igtk_len == len && - os_memcmp(sm->igtk.igtk, igtk->igtk, sm->igtk.igtk_len) == 0) { + if ((sm->igtk.igtk_len == len && + os_memcmp(sm->igtk.igtk, igtk->igtk, sm->igtk.igtk_len) == 0) || + (sm->igtk_wnm_sleep.igtk_len == len && + os_memcmp(sm->igtk_wnm_sleep.igtk, igtk->igtk, + sm->igtk_wnm_sleep.igtk_len) == 0)) { wpa_dbg(sm->ctx->msg_ctx, MSG_DEBUG, "WPA: Not reinstalling already in-use IGTK to the driver (keyidx=%d)", keyidx); @@ -900,8 +913,14 @@ static int wpa_supplicant_install_igtk(struct wpa_sm *sm, return -1; } - sm->igtk.igtk_len = len; - os_memcpy(sm->igtk.igtk, igtk->igtk, sm->igtk.igtk_len); + if (wnm_sleep) { + sm->igtk_wnm_sleep.igtk_len = len; + os_memcpy(sm->igtk_wnm_sleep.igtk, igtk->igtk, + sm->igtk_wnm_sleep.igtk_len); + } else { + sm->igtk.igtk_len = len; + os_memcpy(sm->igtk.igtk, igtk->igtk, sm->igtk.igtk_len); + } return 0; } @@ -924,7 +943,7 @@ static int ieee80211w_set_keys(struct wpa_sm *sm, return -1; igtk = (const struct wpa_igtk_kde *) ie->igtk; - if (wpa_supplicant_install_igtk(sm, igtk) < 0) + if (wpa_supplicant_install_igtk(sm, igtk, 0) < 0) return -1; } @@ -1574,7 +1593,7 @@ static void wpa_supplicant_process_1_of_2(struct wpa_sm *sm, if (wpa_supplicant_rsc_relaxation(sm, key->key_rsc)) key_rsc = null_rsc; - if (wpa_supplicant_install_gtk(sm, &gd, key_rsc) || + if (wpa_supplicant_install_gtk(sm, &gd, key_rsc, 0) || wpa_supplicant_send_2_of_2(sm, key, ver, key_info) < 0) goto failed; os_memset(&gd, 0, sizeof(gd)); @@ -2386,8 +2405,10 @@ void wpa_sm_notify_assoc(struct wpa_sm *sm, const u8 *bssid) sm->tptk_set = 0; os_memset(&sm->tptk, 0, sizeof(sm->tptk)); os_memset(&sm->gtk, 0, sizeof(sm->gtk)); + os_memset(&sm->gtk_wnm_sleep, 0, sizeof(sm->gtk_wnm_sleep)); #ifdef CONFIG_IEEE80211W os_memset(&sm->igtk, 0, sizeof(sm->igtk)); + os_memset(&sm->igtk_wnm_sleep, 0, sizeof(sm->igtk_wnm_sleep)); #endif /* CONFIG_IEEE80211W */ } @@ -2920,8 +2941,10 @@ void wpa_sm_drop_sa(struct wpa_sm *sm) os_memset(&sm->ptk, 0, sizeof(sm->ptk)); os_memset(&sm->tptk, 0, sizeof(sm->tptk)); os_memset(&sm->gtk, 0, sizeof(sm->gtk)); + os_memset(&sm->gtk_wnm_sleep, 0, sizeof(sm->gtk_wnm_sleep)); #ifdef CONFIG_IEEE80211W os_memset(&sm->igtk, 0, sizeof(sm->igtk)); + os_memset(&sm->igtk_wnm_sleep, 0, sizeof(sm->igtk_wnm_sleep)); #endif /* CONFIG_IEEE80211W */ #ifdef CONFIG_IEEE80211R os_memset(sm->xxkey, 0, sizeof(sm->xxkey)); @@ -2986,7 +3009,7 @@ int wpa_wnmsleep_install_key(struct wpa_sm *sm, u8 subelem_id, u8 *buf) wpa_hexdump_key(MSG_DEBUG, "Install GTK (WNM SLEEP)", gd.gtk, gd.gtk_len); - if (wpa_supplicant_install_gtk(sm, &gd, key_rsc)) { + if (wpa_supplicant_install_gtk(sm, &gd, key_rsc, 1)) { os_memset(&gd, 0, sizeof(gd)); wpa_printf(MSG_DEBUG, "Failed to install the GTK in " "WNM mode"); @@ -2998,7 +3021,7 @@ int wpa_wnmsleep_install_key(struct wpa_sm *sm, u8 subelem_id, u8 *buf) const struct wpa_igtk_kde *igtk; igtk = (const struct wpa_igtk_kde *) (buf + 2); - if (wpa_supplicant_install_igtk(sm, igtk) < 0) + if (wpa_supplicant_install_igtk(sm, igtk, 1) < 0) return -1; #endif /* CONFIG_IEEE80211W */ } else { diff --git a/src/rsn_supp/wpa_i.h b/src/rsn_supp/wpa_i.h index afc9e37..9a54631 100644 --- a/src/rsn_supp/wpa_i.h +++ b/src/rsn_supp/wpa_i.h @@ -32,8 +32,10 @@ struct wpa_sm { int rx_replay_counter_set; u8 request_counter[WPA_REPLAY_COUNTER_LEN]; struct wpa_gtk gtk; + struct wpa_gtk gtk_wnm_sleep; #ifdef CONFIG_IEEE80211W struct wpa_igtk igtk; + struct wpa_igtk igtk_wnm_sleep; #endif /* CONFIG_IEEE80211W */ struct eapol_sm *eapol; /* EAPOL state machine from upper level code */ -- 2.7.4 From 8f82bc94e8697a9d47fa8774dfdaaede1084912c Mon Sep 17 00:00:00 2001 From: Mathy Vanhoef Date: Fri, 29 Sep 2017 04:22:51 +0200 Subject: [PATCH 4/8] Prevent installation of an all-zero TK Properly track whether a PTK has already been installed to the driver and the TK part cleared from memory. This prevents an attacker from trying to trick the client into installing an all-zero TK. This fixes the earlier fix in commit ad00d64e7d8827b3cebd665a0ceb08adabf15e1e ('Fix TK configuration to the driver in EAPOL-Key 3/4 retry case') which did not take into account possibility of an extra message 1/4 showing up between retries of message 3/4. Signed-off-by: Mathy Vanhoef --- src/common/wpa_common.h | 1 + src/rsn_supp/wpa.c | 5 ++--- src/rsn_supp/wpa_i.h | 1 - 3 files changed, 3 insertions(+), 4 deletions(-) diff --git a/src/common/wpa_common.h b/src/common/wpa_common.h index d200285..1021ccb 100644 --- a/src/common/wpa_common.h +++ b/src/common/wpa_common.h @@ -215,6 +215,7 @@ struct wpa_ptk { size_t kck_len; size_t kek_len; size_t tk_len; + int installed; /* 1 if key has already been installed to driver */ }; struct wpa_gtk { diff --git a/src/rsn_supp/wpa.c b/src/rsn_supp/wpa.c index 7a2c68d..0550a41 100644 --- a/src/rsn_supp/wpa.c +++ b/src/rsn_supp/wpa.c @@ -510,7 +510,6 @@ static void wpa_supplicant_process_1_of_4(struct wpa_sm *sm, os_memset(buf, 0, sizeof(buf)); } sm->tptk_set = 1; - sm->tk_to_set = 1; kde = sm->assoc_wpa_ie; kde_len = sm->assoc_wpa_ie_len; @@ -615,7 +614,7 @@ static int wpa_supplicant_install_ptk(struct wpa_sm *sm, enum wpa_alg alg; const u8 *key_rsc; - if (!sm->tk_to_set) { + if (sm->ptk.installed) { wpa_dbg(sm->ctx->msg_ctx, MSG_DEBUG, "WPA: Do not re-install same PTK to the driver"); return 0; @@ -659,7 +658,7 @@ static int wpa_supplicant_install_ptk(struct wpa_sm *sm, /* TK is not needed anymore in supplicant */ os_memset(sm->ptk.tk, 0, WPA_TK_MAX_LEN); - sm->tk_to_set = 0; + sm->ptk.installed = 1; if (sm->wpa_ptk_rekey) { eloop_cancel_timeout(wpa_sm_rekey_ptk, sm, NULL); diff --git a/src/rsn_supp/wpa_i.h b/src/rsn_supp/wpa_i.h index 9a54631..41f371f 100644 --- a/src/rsn_supp/wpa_i.h +++ b/src/rsn_supp/wpa_i.h @@ -24,7 +24,6 @@ struct wpa_sm { struct wpa_ptk ptk, tptk; int ptk_set, tptk_set; unsigned int msg_3_of_4_ok:1; - unsigned int tk_to_set:1; u8 snonce[WPA_NONCE_LEN]; u8 anonce[WPA_NONCE_LEN]; /* ANonce from the last 1/4 msg */ int renew_snonce; -- 2.7.4 From 12fac09b437a1dc8a0f253e265934a8aaf4d2f8b Mon Sep 17 00:00:00 2001 From: Jouni Malinen Date: Sun, 1 Oct 2017 12:32:57 +0300 Subject: [PATCH 5/8] Fix PTK rekeying to generate a new ANonce The Authenticator state machine path for PTK rekeying ended up bypassing the AUTHENTICATION2 state where a new ANonce is generated when going directly to the PTKSTART state since there is no need to try to determine the PMK again in such a case. This is far from ideal since the new PTK would depend on a new nonce only from the supplicant. Fix this by generating a new ANonce when moving to the PTKSTART state for the purpose of starting new 4-way handshake to rekey PTK. Signed-off-by: Jouni Malinen --- src/ap/wpa_auth.c | 24 +++++++++++++++++++++--- 1 file changed, 21 insertions(+), 3 deletions(-) diff --git a/src/ap/wpa_auth.c b/src/ap/wpa_auth.c index 707971d..bf10cc1 100644 --- a/src/ap/wpa_auth.c +++ b/src/ap/wpa_auth.c @@ -1901,6 +1901,21 @@ SM_STATE(WPA_PTK, AUTHENTICATION2) } +static int wpa_auth_sm_ptk_update(struct wpa_state_machine *sm) +{ + if (random_get_bytes(sm->ANonce, WPA_NONCE_LEN)) { + wpa_printf(MSG_ERROR, + "WPA: Failed to get random data for ANonce"); + sm->Disconnect = TRUE; + return -1; + } + wpa_hexdump(MSG_DEBUG, "WPA: Assign new ANonce", sm->ANonce, + WPA_NONCE_LEN); + sm->TimeoutCtr = 0; + return 0; +} + + SM_STATE(WPA_PTK, INITPMK) { u8 msk[2 * PMK_LEN]; @@ -2458,9 +2473,12 @@ SM_STEP(WPA_PTK) SM_ENTER(WPA_PTK, AUTHENTICATION); else if (sm->ReAuthenticationRequest) SM_ENTER(WPA_PTK, AUTHENTICATION2); - else if (sm->PTKRequest) - SM_ENTER(WPA_PTK, PTKSTART); - else switch (sm->wpa_ptk_state) { + else if (sm->PTKRequest) { + if (wpa_auth_sm_ptk_update(sm) < 0) + SM_ENTER(WPA_PTK, DISCONNECTED); + else + SM_ENTER(WPA_PTK, PTKSTART); + } else switch (sm->wpa_ptk_state) { case WPA_PTK_INITIALIZE: break; case WPA_PTK_DISCONNECT: -- 2.7.4 From 6c4bed4f47d1960ec04981a9d50e5076aea5223d Mon Sep 17 00:00:00 2001 From: Jouni Malinen Date: Fri, 22 Sep 2017 11:03:15 +0300 Subject: [PATCH 6/8] TDLS: Reject TPK-TK reconfiguration Do not try to reconfigure the same TPK-TK to the driver after it has been successfully configured. This is an explicit check to avoid issues related to resetting the TX/RX packet number. There was already a check for this for TPK M2 (retries of that message are ignored completely), so that behavior does not get modified. For TPK M3, the TPK-TK could have been reconfigured, but that was followed by immediate teardown of the link due to an issue in updating the STA entry. Furthermore, for TDLS with any real security (i.e., ignoring open/WEP), the TPK message exchange is protected on the AP path and simple replay attacks are not feasible. As an additional corner case, make sure the local nonce gets updated if the peer uses a very unlikely "random nonce" of all zeros. Signed-off-by: Jouni Malinen --- src/rsn_supp/tdls.c | 38 ++++++++++++++++++++++++++++++++++++-- 1 file changed, 36 insertions(+), 2 deletions(-) diff --git a/src/rsn_supp/tdls.c b/src/rsn_supp/tdls.c index e424168..9eb9738 100644 --- a/src/rsn_supp/tdls.c +++ b/src/rsn_supp/tdls.c @@ -112,6 +112,7 @@ struct wpa_tdls_peer { u8 tk[16]; /* TPK-TK; assuming only CCMP will be used */ } tpk; int tpk_set; + int tk_set; /* TPK-TK configured to the driver */ int tpk_success; int tpk_in_progress; @@ -192,6 +193,20 @@ static int wpa_tdls_set_key(struct wpa_sm *sm, struct wpa_tdls_peer *peer) u8 rsc[6]; enum wpa_alg alg; + if (peer->tk_set) { + /* + * This same TPK-TK has already been configured to the driver + * and this new configuration attempt (likely due to an + * unexpected retransmitted frame) would result in clearing + * the TX/RX sequence number which can break security, so must + * not allow that to happen. + */ + wpa_printf(MSG_INFO, "TDLS: TPK-TK for the peer " MACSTR + " has already been configured to the driver - do not reconfigure", + MAC2STR(peer->addr)); + return -1; + } + os_memset(rsc, 0, 6); switch (peer->cipher) { @@ -209,12 +224,15 @@ static int wpa_tdls_set_key(struct wpa_sm *sm, struct wpa_tdls_peer *peer) return -1; } + wpa_printf(MSG_DEBUG, "TDLS: Configure pairwise key for peer " MACSTR, + MAC2STR(peer->addr)); if (wpa_sm_set_key(sm, alg, peer->addr, -1, 1, rsc, sizeof(rsc), peer->tpk.tk, key_len) < 0) { wpa_printf(MSG_WARNING, "TDLS: Failed to set TPK to the " "driver"); return -1; } + peer->tk_set = 1; return 0; } @@ -696,7 +714,7 @@ static void wpa_tdls_peer_clear(struct wpa_sm *sm, struct wpa_tdls_peer *peer) peer->cipher = 0; peer->qos_info = 0; peer->wmm_capable = 0; - peer->tpk_set = peer->tpk_success = 0; + peer->tk_set = peer->tpk_set = peer->tpk_success = 0; peer->chan_switch_enabled = 0; os_memset(&peer->tpk, 0, sizeof(peer->tpk)); os_memset(peer->inonce, 0, WPA_NONCE_LEN); @@ -1159,6 +1177,7 @@ skip_rsnie: wpa_tdls_peer_free(sm, peer); return -1; } + peer->tk_set = 0; /* A new nonce results in a new TK */ wpa_hexdump(MSG_DEBUG, "TDLS: Initiator Nonce for TPK handshake", peer->inonce, WPA_NONCE_LEN); os_memcpy(ftie->Snonce, peer->inonce, WPA_NONCE_LEN); @@ -1751,6 +1770,19 @@ static int wpa_tdls_addset_peer(struct wpa_sm *sm, struct wpa_tdls_peer *peer, } +static int tdls_nonce_set(const u8 *nonce) +{ + int i; + + for (i = 0; i < WPA_NONCE_LEN; i++) { + if (nonce[i]) + return 1; + } + + return 0; +} + + static int wpa_tdls_process_tpk_m1(struct wpa_sm *sm, const u8 *src_addr, const u8 *buf, size_t len) { @@ -2004,7 +2036,8 @@ skip_rsn: peer->rsnie_i_len = kde.rsn_ie_len; peer->cipher = cipher; - if (os_memcmp(peer->inonce, ftie->Snonce, WPA_NONCE_LEN) != 0) { + if (os_memcmp(peer->inonce, ftie->Snonce, WPA_NONCE_LEN) != 0 || + !tdls_nonce_set(peer->inonce)) { /* * There is no point in updating the RNonce for every obtained * TPK M1 frame (e.g., retransmission due to timeout) with the @@ -2020,6 +2053,7 @@ skip_rsn: "TDLS: Failed to get random data for responder nonce"); goto error; } + peer->tk_set = 0; /* A new nonce results in a new TK */ } #if 0 -- 2.7.4 From 53c5eb58e95004f86e65ee9fbfccbc291b139057 Mon Sep 17 00:00:00 2001 From: Jouni Malinen Date: Fri, 22 Sep 2017 11:25:02 +0300 Subject: [PATCH 7/8] WNM: Ignore WNM-Sleep Mode Response without pending request Commit 03ed0a52393710be6bdae657d1b36efa146520e5 ('WNM: Ignore WNM-Sleep Mode Response if WNM-Sleep Mode has not been used') started ignoring the response when no WNM-Sleep Mode Request had been used during the association. This can be made tighter by clearing the used flag when successfully processing a response. This adds an additional layer of protection against unexpected retransmissions of the response frame. Signed-off-by: Jouni Malinen --- wpa_supplicant/wnm_sta.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/wpa_supplicant/wnm_sta.c b/wpa_supplicant/wnm_sta.c index 1b3409c..67a07ff 100644 --- a/wpa_supplicant/wnm_sta.c +++ b/wpa_supplicant/wnm_sta.c @@ -260,7 +260,7 @@ static void ieee802_11_rx_wnmsleep_resp(struct wpa_supplicant *wpa_s, if (!wpa_s->wnmsleep_used) { wpa_printf(MSG_DEBUG, - "WNM: Ignore WNM-Sleep Mode Response frame since WNM-Sleep Mode has not been used in this association"); + "WNM: Ignore WNM-Sleep Mode Response frame since WNM-Sleep Mode operation has not been requested"); return; } @@ -299,6 +299,8 @@ static void ieee802_11_rx_wnmsleep_resp(struct wpa_supplicant *wpa_s, return; } + wpa_s->wnmsleep_used = 0; + if (wnmsleep_ie->status == WNM_STATUS_SLEEP_ACCEPT || wnmsleep_ie->status == WNM_STATUS_SLEEP_EXIT_ACCEPT_GTK_UPDATE) { wpa_printf(MSG_DEBUG, "Successfully recv WNM-Sleep Response " -- 2.7.4 From b372ab0b7daea719749194dc554b26e6367603f2 Mon Sep 17 00:00:00 2001 From: Jouni Malinen Date: Fri, 22 Sep 2017 12:06:37 +0300 Subject: [PATCH 8/8] FT: Do not allow multiple Reassociation Response frames The driver is expected to not report a second association event without the station having explicitly request a new association. As such, this case should not be reachable. However, since reconfiguring the same pairwise or group keys to the driver could result in nonce reuse issues, be extra careful here and do an additional state check to avoid this even if the local driver ends up somehow accepting an unexpected Reassociation Response frame. Signed-off-by: Jouni Malinen --- src/rsn_supp/wpa.c | 3 +++ src/rsn_supp/wpa_ft.c | 8 ++++++++ src/rsn_supp/wpa_i.h | 1 + 3 files changed, 12 insertions(+) diff --git a/src/rsn_supp/wpa.c b/src/rsn_supp/wpa.c index 0550a41..2a53c6f 100644 --- a/src/rsn_supp/wpa.c +++ b/src/rsn_supp/wpa.c @@ -2440,6 +2440,9 @@ void wpa_sm_notify_disassoc(struct wpa_sm *sm) #ifdef CONFIG_TDLS wpa_tdls_disassoc(sm); #endif /* CONFIG_TDLS */ +#ifdef CONFIG_IEEE80211R + sm->ft_reassoc_completed = 0; +#endif /* CONFIG_IEEE80211R */ /* Keys are not needed in the WPA state machine anymore */ wpa_sm_drop_sa(sm); diff --git a/src/rsn_supp/wpa_ft.c b/src/rsn_supp/wpa_ft.c index 205793e..d45bb45 100644 --- a/src/rsn_supp/wpa_ft.c +++ b/src/rsn_supp/wpa_ft.c @@ -153,6 +153,7 @@ static u8 * wpa_ft_gen_req_ies(struct wpa_sm *sm, size_t *len, u16 capab; sm->ft_completed = 0; + sm->ft_reassoc_completed = 0; buf_len = 2 + sizeof(struct rsn_mdie) + 2 + sizeof(struct rsn_ftie) + 2 + sm->r0kh_id_len + ric_ies_len + 100; @@ -681,6 +682,11 @@ int wpa_ft_validate_reassoc_resp(struct wpa_sm *sm, const u8 *ies, return -1; } + if (sm->ft_reassoc_completed) { + wpa_printf(MSG_DEBUG, "FT: Reassociation has already been completed for this FT protocol instance - ignore unexpected retransmission"); + return 0; + } + if (wpa_ft_parse_ies(ies, ies_len, &parse) < 0) { wpa_printf(MSG_DEBUG, "FT: Failed to parse IEs"); return -1; @@ -781,6 +787,8 @@ int wpa_ft_validate_reassoc_resp(struct wpa_sm *sm, const u8 *ies, return -1; } + sm->ft_reassoc_completed = 1; + if (wpa_ft_process_gtk_subelem(sm, parse.gtk, parse.gtk_len) < 0) return -1; diff --git a/src/rsn_supp/wpa_i.h b/src/rsn_supp/wpa_i.h index 41f371f..56f88dc 100644 --- a/src/rsn_supp/wpa_i.h +++ b/src/rsn_supp/wpa_i.h @@ -128,6 +128,7 @@ struct wpa_sm { size_t r0kh_id_len; u8 r1kh_id[FT_R1KH_ID_LEN]; int ft_completed; + int ft_reassoc_completed; int over_the_ds_in_progress; u8 target_ap[ETH_ALEN]; /* over-the-DS target AP */ int set_ptk_after_assoc; -- 2.7.4