mac80211: split managed/ibss code a little more

It appears that you can completely mess up mac80211 in IBSS
mode by sending it a disassoc or deauth: it'll stop queues
and do a lot more but not ever do anything again. Fix this
by not handling all those frames in IBSS mode,

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 146 insertions, 108 deletions

diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 332397415890..fbb766afe599 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -808,9 +808,6 @@ static void ieee80211_set_associated(struct ieee80211_sub_if_data *sdata,
         bss_info_changed |= BSS_CHANGED_ASSOC;
         ifsta->flags |= IEEE80211_STA_ASSOCIATED;
 
-        if (sdata->vif.type != NL80211_IFTYPE_STATION)
-                return;
-
         bss = ieee80211_rx_bss_get(local, ifsta->bssid,
                                    conf->channel->center_freq,
                                    ifsta->ssid, ifsta->ssid_len);
@@ -1169,6 +1166,30 @@ static void ieee80211_auth_challenge(struct ieee80211_sub_if_data *sdata,
                             elems.challenge_len + 2, 1);
 }
 
+static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
+                                        struct ieee80211_if_sta *ifsta,
+                                        struct ieee80211_mgmt *mgmt,
+                                        size_t len)
+{
+        u16 auth_alg, auth_transaction, status_code;
+
+        if (len < 24 + 6)
+                return;
+
+        auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
+        auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
+        status_code = le16_to_cpu(mgmt->u.auth.status_code);
+
+        /*
+         * IEEE 802.11 standard does not require authentication in IBSS
+         * networks and most implementations do not seem to use it.
+         * However, try to reply to authentication attempts if someone
+         * has actually implemented this.
+         */
+        if (auth_alg == WLAN_AUTH_OPEN && auth_transaction == 1)
+                ieee80211_send_auth(sdata, ifsta, 2, NULL, 0, 0);
+}
+
 static void ieee80211_rx_mgmt_auth(struct ieee80211_sub_if_data *sdata,
                                    struct ieee80211_if_sta *ifsta,
                                    struct ieee80211_mgmt *mgmt,
@@ -1176,38 +1197,22 @@ static void ieee80211_rx_mgmt_auth(struct ieee80211_sub_if_data *sdata,
 {
         u16 auth_alg, auth_transaction, status_code;
 
-        if (ifsta->state != IEEE80211_STA_MLME_AUTHENTICATE &&
-            sdata->vif.type != NL80211_IFTYPE_ADHOC)
+        if (ifsta->state != IEEE80211_STA_MLME_AUTHENTICATE)
                 return;
 
         if (len < 24 + 6)
                 return;
 
-        if (sdata->vif.type != NL80211_IFTYPE_ADHOC &&
-            memcmp(ifsta->bssid, mgmt->sa, ETH_ALEN) != 0)
+        if (memcmp(ifsta->bssid, mgmt->sa, ETH_ALEN) != 0)
                 return;
 
-        if (sdata->vif.type != NL80211_IFTYPE_ADHOC &&
-            memcmp(ifsta->bssid, mgmt->bssid, ETH_ALEN) != 0)
+        if (memcmp(ifsta->bssid, mgmt->bssid, ETH_ALEN) != 0)
                 return;
 
         auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
         auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
         status_code = le16_to_cpu(mgmt->u.auth.status_code);
 
-        if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
-                /*
-                 * IEEE 802.11 standard does not require authentication in IBSS
-                 * networks and most implementations do not seem to use it.
-                 * However, try to reply to authentication attempts if someone
-                 * has actually implemented this.
-                 */
-                if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
-                        return;
-                ieee80211_send_auth(sdata, ifsta, 2, NULL, 0, 0);
-                return;
-        }
-
         if (auth_alg != ifsta->auth_alg ||
             auth_transaction != ifsta->auth_transaction)
                 return;
@@ -1762,74 +1767,85 @@ static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
         /* was just updated in ieee80211_bss_info_update */
         beacon_timestamp = bss->cbss.tsf;
 
-        /*
-         * In STA mode, the remaining parameters should not be overridden
-         * by beacons because they're not necessarily accurate there.
-         */
-        if (sdata->vif.type != NL80211_IFTYPE_ADHOC &&
-            bss->last_probe_resp && beacon) {
-                ieee80211_rx_bss_put(local, bss);
-                return;
-        }
+        if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
+                goto put_bss;
 
         /* check if we need to merge IBSS */
-        if (sdata->vif.type == NL80211_IFTYPE_ADHOC && beacon &&
-            (!(sdata->u.sta.flags & IEEE80211_STA_BSSID_SET)) &&
-            bss->cbss.capability & WLAN_CAPABILITY_IBSS &&
-            bss->cbss.channel == local->oper_channel &&
-            elems->ssid_len == sdata->u.sta.ssid_len &&
+
+        /* merge only on beacons (???) */
+        if (!beacon)
+                goto put_bss;
+
+        /* we use a fixed BSSID */
+        if (sdata->u.sta.flags & IEEE80211_STA_BSSID_SET)
+                goto put_bss;
+
+        /* not an IBSS */
+        if (!(bss->cbss.capability & WLAN_CAPABILITY_IBSS))
+                goto put_bss;
+
+        /* different channel */
+        if (bss->cbss.channel != local->oper_channel)
+                goto put_bss;
+
+        /* different SSID */
+        if (elems->ssid_len != sdata->u.sta.ssid_len ||
             memcmp(elems->ssid, sdata->u.sta.ssid,
-                                sdata->u.sta.ssid_len) == 0) {
-                if (rx_status->flag & RX_FLAG_TSFT) {
-                        /* in order for correct IBSS merging we need mactime
-                         *
-                         * since mactime is defined as the time the first data
-                         * symbol of the frame hits the PHY, and the timestamp
-                         * of the beacon is defined as "the time that the data
-                         * symbol containing the first bit of the timestamp is
-                         * transmitted to the PHY plus the transmitting STA’s
-                         * delays through its local PHY from the MAC-PHY
-                         * interface to its interface with the WM"
-                         * (802.11 11.1.2) - equals the time this bit arrives at
-                         * the receiver - we have to take into account the
-                         * offset between the two.
-                         * e.g: at 1 MBit that means mactime is 192 usec earlier
-                         * (=24 bytes * 8 usecs/byte) than the beacon timestamp.
-                         */
-                        int rate;
-                        if (rx_status->flag & RX_FLAG_HT) {
-                                rate = 65; /* TODO: HT rates */
-                        } else {
-                                rate = local->hw.wiphy->bands[band]->
-                                        bitrates[rx_status->rate_idx].bitrate;
-                        }
-                        rx_timestamp = rx_status->mactime + (24 * 8 * 10 / rate);
-                } else if (local && local->ops && local->ops->get_tsf)
-                        /* second best option: get current TSF */
-                        rx_timestamp = local->ops->get_tsf(local_to_hw(local));
+                                sdata->u.sta.ssid_len))
+                goto put_bss;
+
+        if (rx_status->flag & RX_FLAG_TSFT) {
+                /*
+                 * For correct IBSS merging we need mactime; since mactime is
+                 * defined as the time the first data symbol of the frame hits
+                 * the PHY, and the timestamp of the beacon is defined as "the
+                 * time that the data symbol containing the first bit of the
+                 * timestamp is transmitted to the PHY plus the transmitting
+                 * STA's delays through its local PHY from the MAC-PHY
+                 * interface to its interface with the WM" (802.11 11.1.2)
+                 * - equals the time this bit arrives at the receiver - we have
+                 * to take into account the offset between the two.
+                 *
+                 * E.g. at 1 MBit that means mactime is 192 usec earlier
+                 * (=24 bytes * 8 usecs/byte) than the beacon timestamp.
+                 */
+                int rate;
+
+                if (rx_status->flag & RX_FLAG_HT)
+                        rate = 65; /* TODO: HT rates */
                 else
-                        /* can't merge without knowing the TSF */
-                        rx_timestamp = -1LLU;
+                        rate = local->hw.wiphy->bands[band]->
+                                bitrates[rx_status->rate_idx].bitrate;
+
+                rx_timestamp = rx_status->mactime + (24 * 8 * 10 / rate);
+        } else if (local && local->ops && local->ops->get_tsf)
+                /* second best option: get current TSF */
+                rx_timestamp = local->ops->get_tsf(local_to_hw(local));
+        else
+                /* can't merge without knowing the TSF */
+                rx_timestamp = -1LLU;
+
 #ifdef CONFIG_MAC80211_IBSS_DEBUG
-                printk(KERN_DEBUG "RX beacon SA=%pM BSSID="
-                       "%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
-                       mgmt->sa, mgmt->bssid,
-                       (unsigned long long)rx_timestamp,
-                       (unsigned long long)beacon_timestamp,
-                       (unsigned long long)(rx_timestamp - beacon_timestamp),
-                       jiffies);
-#endif /* CONFIG_MAC80211_IBSS_DEBUG */
-                if (beacon_timestamp > rx_timestamp) {
+        printk(KERN_DEBUG "RX beacon SA=%pM BSSID="
+               "%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
+               mgmt->sa, mgmt->bssid,
+               (unsigned long long)rx_timestamp,
+               (unsigned long long)beacon_timestamp,
+               (unsigned long long)(rx_timestamp - beacon_timestamp),
+               jiffies);
+#endif
+
+        if (beacon_timestamp > rx_timestamp) {
 #ifdef CONFIG_MAC80211_IBSS_DEBUG
-                        printk(KERN_DEBUG "%s: beacon TSF higher than "
-                               "local TSF - IBSS merge with BSSID %pM\n",
-                               sdata->dev->name, mgmt->bssid);
+                printk(KERN_DEBUG "%s: beacon TSF higher than "
+                       "local TSF - IBSS merge with BSSID %pM\n",
+                       sdata->dev->name, mgmt->bssid);
 #endif
-                        ieee80211_sta_join_ibss(sdata, &sdata->u.sta, bss);
-                        ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, supp_rates);
-                }
+                ieee80211_sta_join_ibss(sdata, &sdata->u.sta, bss);
+                ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, supp_rates);
         }
 
+ put_bss:
         ieee80211_rx_bss_put(local, bss);
 }
 
@@ -1993,8 +2009,7 @@ static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
         struct ieee80211_mgmt *resp;
         u8 *pos, *end;
 
-        if (sdata->vif.type != NL80211_IFTYPE_ADHOC ||
-            ifsta->state != IEEE80211_STA_MLME_IBSS_JOINED ||
+        if (ifsta->state != IEEE80211_STA_MLME_IBSS_JOINED ||
             len < 24 + 2 || !ifsta->probe_resp)
                 return;
 
@@ -2098,31 +2113,54 @@ static void ieee80211_sta_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
         mgmt = (struct ieee80211_mgmt *) skb->data;
         fc = le16_to_cpu(mgmt->frame_control);
 
-        switch (fc & IEEE80211_FCTL_STYPE) {
-        case IEEE80211_STYPE_PROBE_REQ:
-                ieee80211_rx_mgmt_probe_req(sdata, ifsta, mgmt, skb->len);
-                break;
-        case IEEE80211_STYPE_PROBE_RESP:
-                ieee80211_rx_mgmt_probe_resp(sdata, mgmt, skb->len, rx_status);
-                break;
-        case IEEE80211_STYPE_BEACON:
-                ieee80211_rx_mgmt_beacon(sdata, mgmt, skb->len, rx_status);
-                break;
-        case IEEE80211_STYPE_AUTH:
-                ieee80211_rx_mgmt_auth(sdata, ifsta, mgmt, skb->len);
-                break;
-        case IEEE80211_STYPE_ASSOC_RESP:
-                ieee80211_rx_mgmt_assoc_resp(sdata, ifsta, mgmt, skb->len, 0);
-                break;
-        case IEEE80211_STYPE_REASSOC_RESP:
-                ieee80211_rx_mgmt_assoc_resp(sdata, ifsta, mgmt, skb->len, 1);
-                break;
-        case IEEE80211_STYPE_DEAUTH:
-                ieee80211_rx_mgmt_deauth(sdata, ifsta, mgmt, skb->len);
-                break;
-        case IEEE80211_STYPE_DISASSOC:
-                ieee80211_rx_mgmt_disassoc(sdata, ifsta, mgmt, skb->len);
-                break;
+        if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
+                switch (fc & IEEE80211_FCTL_STYPE) {
+                case IEEE80211_STYPE_PROBE_REQ:
+                        ieee80211_rx_mgmt_probe_req(sdata, ifsta, mgmt,
+                                                    skb->len);
+                        break;
+                case IEEE80211_STYPE_PROBE_RESP:
+                        ieee80211_rx_mgmt_probe_resp(sdata, mgmt, skb->len,
+                                                     rx_status);
+                        break;
+                case IEEE80211_STYPE_BEACON:
+                        ieee80211_rx_mgmt_beacon(sdata, mgmt, skb->len,
+                                                 rx_status);
+                        break;
+                case IEEE80211_STYPE_AUTH:
+                        ieee80211_rx_mgmt_auth_ibss(sdata, ifsta, mgmt,
+                                                    skb->len);
+                        break;
+                }
+        } else { /* NL80211_IFTYPE_STATION */
+                switch (fc & IEEE80211_FCTL_STYPE) {
+                case IEEE80211_STYPE_PROBE_RESP:
+                        ieee80211_rx_mgmt_probe_resp(sdata, mgmt, skb->len,
+                                                     rx_status);
+                        break;
+                case IEEE80211_STYPE_BEACON:
+                        ieee80211_rx_mgmt_beacon(sdata, mgmt, skb->len,
+                                                 rx_status);
+                        break;
+                case IEEE80211_STYPE_AUTH:
+                        ieee80211_rx_mgmt_auth(sdata, ifsta, mgmt, skb->len);
+                        break;
+                case IEEE80211_STYPE_ASSOC_RESP:
+                        ieee80211_rx_mgmt_assoc_resp(sdata, ifsta, mgmt,
+                                                     skb->len, 0);
+                        break;
+                case IEEE80211_STYPE_REASSOC_RESP:
+                        ieee80211_rx_mgmt_assoc_resp(sdata, ifsta, mgmt,
+                                                     skb->len, 1);
+                        break;
+                case IEEE80211_STYPE_DEAUTH:
+                        ieee80211_rx_mgmt_deauth(sdata, ifsta, mgmt, skb->len);
+                        break;
+                case IEEE80211_STYPE_DISASSOC:
+                        ieee80211_rx_mgmt_disassoc(sdata, ifsta, mgmt,
+                                                   skb->len);
+                        break;
+                }
         }
 
         kfree_skb(skb);