diff options
Diffstat (limited to 'network/hostapd/patches/rebased-v2.6-0006-TDLS-Reject-TPK-TK-reconfiguration.patch')
| -rw-r--r-- | network/hostapd/patches/rebased-v2.6-0006-TDLS-Reject-TPK-TK-reconfiguration.patch | 132 |
1 files changed, 132 insertions, 0 deletions
diff --git a/network/hostapd/patches/rebased-v2.6-0006-TDLS-Reject-TPK-TK-reconfiguration.patch b/network/hostapd/patches/rebased-v2.6-0006-TDLS-Reject-TPK-TK-reconfiguration.patch new file mode 100644 index 0000000000..e1bd5a5726 --- /dev/null +++ b/network/hostapd/patches/rebased-v2.6-0006-TDLS-Reject-TPK-TK-reconfiguration.patch @@ -0,0 +1,132 @@ +From 6c4bed4f47d1960ec04981a9d50e5076aea5223d Mon Sep 17 00:00:00 2001 +From: Jouni Malinen <j@w1.fi> +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 <j@w1.fi> +--- + 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 + |