diff options
-rw-r--r-- | net/mac80211/ieee80211_i.h | 41 | ||||
-rw-r--r-- | net/mac80211/mlme.c | 14 | ||||
-rw-r--r-- | net/mac80211/scan.c | 71 | ||||
-rw-r--r-- | net/mac80211/util.c | 37 |
4 files changed, 141 insertions, 22 deletions
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index 24cb108..796b13b 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -105,6 +105,44 @@ struct ieee80211_bss { */ bool has_erp_value; u8 erp_value; + + /* Keep track of the corruption of the last beacon/probe response. */ + u8 corrupt_data; + + /* Keep track of what bits of information we have valid info for. */ + u8 valid_data; +}; + +/** + * enum ieee80211_corrupt_data_flags - BSS data corruption flags + * @IEEE80211_BSS_CORRUPT_BEACON: last beacon frame received was corrupted + * @IEEE80211_BSS_CORRUPT_PROBE_RESP: last probe response received was corrupted + * + * These are bss flags that are attached to a bss in the + * @corrupt_data field of &struct ieee80211_bss. + */ +enum ieee80211_bss_corrupt_data_flags { + IEEE80211_BSS_CORRUPT_BEACON = BIT(0), + IEEE80211_BSS_CORRUPT_PROBE_RESP = BIT(1) +}; + +/** + * enum ieee80211_valid_data_flags - BSS valid data flags + * @IEEE80211_BSS_VALID_DTIM: DTIM data was gathered from non-corrupt IE + * @IEEE80211_BSS_VALID_WMM: WMM/UAPSD data was gathered from non-corrupt IE + * @IEEE80211_BSS_VALID_RATES: Supported rates were gathered from non-corrupt IE + * @IEEE80211_BSS_VALID_ERP: ERP flag was gathered from non-corrupt IE + * + * These are bss flags that are attached to a bss in the + * @valid_data field of &struct ieee80211_bss. They show which parts + * of the data structure were recieved as a result of an un-corrupted + * beacon/probe response. + */ +enum ieee80211_bss_valid_data_flags { + IEEE80211_BSS_VALID_DTIM = BIT(0), + IEEE80211_BSS_VALID_WMM = BIT(1), + IEEE80211_BSS_VALID_RATES = BIT(2), + IEEE80211_BSS_VALID_ERP = BIT(3) }; static inline u8 *bss_mesh_cfg(struct ieee80211_bss *bss) @@ -1120,6 +1158,9 @@ struct ieee802_11_elems { u8 quiet_elem_len; u8 num_of_quiet_elem; /* can be more the one */ u8 timeout_int_len; + + /* whether a parse error occurred while retrieving these elements */ + bool parse_error; }; static inline struct ieee80211_local *hw_to_local( diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c index 92c5eb1..c08924a 100644 --- a/net/mac80211/mlme.c +++ b/net/mac80211/mlme.c @@ -3446,6 +3446,20 @@ int ieee80211_mgd_assoc(struct ieee80211_sub_if_data *sdata, } run_again(ifmgd, assoc_data->timeout); + if (bss->corrupt_data) { + char *corrupt_type = "data"; + if (bss->corrupt_data & IEEE80211_BSS_CORRUPT_BEACON) { + if (bss->corrupt_data & + IEEE80211_BSS_CORRUPT_PROBE_RESP) + corrupt_type = "beacon and probe response"; + else + corrupt_type = "beacon"; + } else if (bss->corrupt_data & IEEE80211_BSS_CORRUPT_PROBE_RESP) + corrupt_type = "probe response"; + printk(KERN_DEBUG "%s: associating with AP with corrupt %s\n", + sdata->name, corrupt_type); + } + err = 0; goto out; err_clear: diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c index a9d7235..33cd169 100644 --- a/net/mac80211/scan.c +++ b/net/mac80211/scan.c @@ -104,16 +104,35 @@ ieee80211_bss_info_update(struct ieee80211_local *local, cbss->free_priv = ieee80211_rx_bss_free; bss = (void *)cbss->priv; + if (elems->parse_error) { + if (beacon) + bss->corrupt_data |= IEEE80211_BSS_CORRUPT_BEACON; + else + bss->corrupt_data |= IEEE80211_BSS_CORRUPT_PROBE_RESP; + } else { + if (beacon) + bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_BEACON; + else + bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_PROBE_RESP; + } + /* save the ERP value so that it is available at association time */ - if (elems->erp_info && elems->erp_info_len >= 1) { + if (elems->erp_info && elems->erp_info_len >= 1 && + (!elems->parse_error || + !(bss->valid_data & IEEE80211_BSS_VALID_ERP))) { bss->erp_value = elems->erp_info[0]; bss->has_erp_value = true; + if (!elems->parse_error) + bss->valid_data |= IEEE80211_BSS_VALID_ERP; } - if (elems->tim) { + if (elems->tim && (!elems->parse_error || + !(bss->valid_data & IEEE80211_BSS_VALID_DTIM))) { struct ieee80211_tim_ie *tim_ie = (struct ieee80211_tim_ie *)elems->tim; bss->dtim_period = tim_ie->dtim_period; + if (!elems->parse_error) + bss->valid_data |= IEEE80211_BSS_VALID_DTIM; } /* If the beacon had no TIM IE, or it was invalid, use 1 */ @@ -121,26 +140,38 @@ ieee80211_bss_info_update(struct ieee80211_local *local, bss->dtim_period = 1; /* replace old supported rates if we get new values */ - srlen = 0; - if (elems->supp_rates) { - clen = IEEE80211_MAX_SUPP_RATES; - if (clen > elems->supp_rates_len) - clen = elems->supp_rates_len; - memcpy(bss->supp_rates, elems->supp_rates, clen); - srlen += clen; - } - if (elems->ext_supp_rates) { - clen = IEEE80211_MAX_SUPP_RATES - srlen; - if (clen > elems->ext_supp_rates_len) - clen = elems->ext_supp_rates_len; - memcpy(bss->supp_rates + srlen, elems->ext_supp_rates, clen); - srlen += clen; + if (!elems->parse_error || + !(bss->valid_data & IEEE80211_BSS_VALID_RATES)) { + srlen = 0; + if (elems->supp_rates) { + clen = IEEE80211_MAX_SUPP_RATES; + if (clen > elems->supp_rates_len) + clen = elems->supp_rates_len; + memcpy(bss->supp_rates, elems->supp_rates, clen); + srlen += clen; + } + if (elems->ext_supp_rates) { + clen = IEEE80211_MAX_SUPP_RATES - srlen; + if (clen > elems->ext_supp_rates_len) + clen = elems->ext_supp_rates_len; + memcpy(bss->supp_rates + srlen, elems->ext_supp_rates, + clen); + srlen += clen; + } + if (srlen) { + bss->supp_rates_len = srlen; + if (!elems->parse_error) + bss->valid_data |= IEEE80211_BSS_VALID_RATES; + } } - if (srlen) - bss->supp_rates_len = srlen; - bss->wmm_used = elems->wmm_param || elems->wmm_info; - bss->uapsd_supported = is_uapsd_supported(elems); + if (!elems->parse_error || + !(bss->valid_data & IEEE80211_BSS_VALID_WMM)) { + bss->wmm_used = elems->wmm_param || elems->wmm_info; + bss->uapsd_supported = is_uapsd_supported(elems); + if (!elems->parse_error) + bss->valid_data |= IEEE80211_BSS_VALID_WMM; + } if (!beacon) bss->last_probe_resp = jiffies; diff --git a/net/mac80211/util.c b/net/mac80211/util.c index 0a5ad95..32f7a3b 100644 --- a/net/mac80211/util.c +++ b/net/mac80211/util.c @@ -572,24 +572,40 @@ u32 ieee802_11_parse_elems_crc(u8 *start, size_t len, size_t left = len; u8 *pos = start; bool calc_crc = filter != 0; + DECLARE_BITMAP(seen_elems, 256); + bitmap_zero(seen_elems, 256); memset(elems, 0, sizeof(*elems)); elems->ie_start = start; elems->total_len = len; while (left >= 2) { u8 id, elen; + bool elem_parse_failed; id = *pos++; elen = *pos++; left -= 2; - if (elen > left) + if (elen > left) { + elems->parse_error = true; break; + } + + if (id != WLAN_EID_VENDOR_SPECIFIC && + id != WLAN_EID_QUIET && + test_bit(id, seen_elems)) { + elems->parse_error = true; + left -= elen; + pos += elen; + continue; + } if (calc_crc && id < 64 && (filter & (1ULL << id))) crc = crc32_be(crc, pos - 2, elen + 2); + elem_parse_failed = false; + switch (id) { case WLAN_EID_SSID: elems->ssid = pos; @@ -615,7 +631,8 @@ u32 ieee802_11_parse_elems_crc(u8 *start, size_t len, if (elen >= sizeof(struct ieee80211_tim_ie)) { elems->tim = (void *)pos; elems->tim_len = elen; - } + } else + elem_parse_failed = true; break; case WLAN_EID_IBSS_PARAMS: elems->ibss_params = pos; @@ -664,10 +681,14 @@ u32 ieee802_11_parse_elems_crc(u8 *start, size_t len, case WLAN_EID_HT_CAPABILITY: if (elen >= sizeof(struct ieee80211_ht_cap)) elems->ht_cap_elem = (void *)pos; + else + elem_parse_failed = true; break; case WLAN_EID_HT_INFORMATION: if (elen >= sizeof(struct ieee80211_ht_info)) elems->ht_info_elem = (void *)pos; + else + elem_parse_failed = true; break; case WLAN_EID_MESH_ID: elems->mesh_id = pos; @@ -676,6 +697,8 @@ u32 ieee802_11_parse_elems_crc(u8 *start, size_t len, case WLAN_EID_MESH_CONFIG: if (elen >= sizeof(struct ieee80211_meshconf_ie)) elems->mesh_config = (void *)pos; + else + elem_parse_failed = true; break; case WLAN_EID_PEER_MGMT: elems->peering = pos; @@ -696,6 +719,8 @@ u32 ieee802_11_parse_elems_crc(u8 *start, size_t len, case WLAN_EID_RANN: if (elen >= sizeof(struct ieee80211_rann_ie)) elems->rann = (void *)pos; + else + elem_parse_failed = true; break; case WLAN_EID_CHANNEL_SWITCH: elems->ch_switch_elem = pos; @@ -724,10 +749,18 @@ u32 ieee802_11_parse_elems_crc(u8 *start, size_t len, break; } + if (elem_parse_failed) + elems->parse_error = true; + else + set_bit(id, seen_elems); + left -= elen; pos += elen; } + if (left != 0) + elems->parse_error = true; + return crc; } |