From: Michael Wu Date: Thu, 31 Jan 2008 18:48:27 +0000 (+0100) Subject: mac80211: Add cooked monitor mode support X-Git-Tag: v2.6.26-rc1~1138^2~530^2~86 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3d30d949cf3f9763393f3457721bca3ac2426e42;p=linux-2.6 mac80211: Add cooked monitor mode support This adds "cooked" monitor mode to mac80211. A monitor interface in "cooked" mode will see all frames that mac80211 has not used internally. Signed-off-by: Michael Wu Signed-off-by: Johannes Berg Signed-off-by: John W. Linville --- diff --git a/net/mac80211/ieee80211.c b/net/mac80211/ieee80211.c index 78fd91895c..91f06c3f4a 100644 --- a/net/mac80211/ieee80211.c +++ b/net/mac80211/ieee80211.c @@ -239,6 +239,11 @@ static int ieee80211_open(struct net_device *dev) /* no need to tell driver */ break; case IEEE80211_IF_TYPE_MNTR: + if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) { + local->cooked_mntrs++; + break; + } + /* must be before the call to ieee80211_configure_filter */ local->monitors++; if (local->monitors == 1) @@ -370,6 +375,11 @@ static int ieee80211_stop(struct net_device *dev) /* no need to tell driver */ break; case IEEE80211_IF_TYPE_MNTR: + if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) { + local->cooked_mntrs--; + break; + } + local->monitors--; if (local->monitors == 0) local->hw.conf.flags &= ~IEEE80211_CONF_RADIOTAP; @@ -1177,7 +1187,7 @@ void ieee80211_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb, u16 frag, type; struct ieee80211_tx_status_rtap_hdr *rthdr; struct ieee80211_sub_if_data *sdata; - int monitors; + struct net_device *prev_dev = NULL; if (!status) { printk(KERN_ERR @@ -1290,7 +1300,11 @@ void ieee80211_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb, /* this was a transmitted frame, but now we want to reuse it */ skb_orphan(skb); - if (!local->monitors) { + /* + * This is a bit racy but we can avoid a lot of work + * with this test... + */ + if (!local->monitors && !local->cooked_mntrs) { dev_kfree_skb(skb); return; } @@ -1324,42 +1338,37 @@ void ieee80211_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb, rthdr->data_retries = status->retry_count; + /* XXX: is this sufficient for BPF? */ + skb_set_mac_header(skb, 0); + skb->ip_summed = CHECKSUM_UNNECESSARY; + skb->pkt_type = PACKET_OTHERHOST; + skb->protocol = htons(ETH_P_802_2); + memset(skb->cb, 0, sizeof(skb->cb)); + rcu_read_lock(); - monitors = local->monitors; list_for_each_entry_rcu(sdata, &local->interfaces, list) { - /* - * Using the monitors counter is possibly racy, but - * if the value is wrong we simply either clone the skb - * once too much or forget sending it to one monitor iface - * The latter case isn't nice but fixing the race is much - * more complicated. - */ - if (!monitors || !skb) - goto out; - if (sdata->vif.type == IEEE80211_IF_TYPE_MNTR) { if (!netif_running(sdata->dev)) continue; - monitors--; - if (monitors) + + if (prev_dev) { skb2 = skb_clone(skb, GFP_ATOMIC); - else - skb2 = NULL; - skb->dev = sdata->dev; - /* XXX: is this sufficient for BPF? */ - skb_set_mac_header(skb, 0); - skb->ip_summed = CHECKSUM_UNNECESSARY; - skb->pkt_type = PACKET_OTHERHOST; - skb->protocol = htons(ETH_P_802_2); - memset(skb->cb, 0, sizeof(skb->cb)); - netif_rx(skb); - skb = skb2; + if (skb2) { + skb2->dev = prev_dev; + netif_rx(skb2); + } + } + + prev_dev = sdata->dev; } } - out: + if (prev_dev) { + skb->dev = prev_dev; + netif_rx(skb); + skb = NULL; + } rcu_read_unlock(); - if (skb) - dev_kfree_skb(skb); + dev_kfree_skb(skb); } EXPORT_SYMBOL(ieee80211_tx_status); diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index 1129a4299d..1b4a449703 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -131,6 +131,7 @@ typedef unsigned __bitwise__ ieee80211_rx_result; #define IEEE80211_TXRXD_RXRA_MATCH BIT(5) #define IEEE80211_TXRXD_TX_INJECTED BIT(6) #define IEEE80211_TXRXD_RX_AMSDU BIT(7) +#define IEEE80211_TXRXD_RX_CMNTR_REPORTED BIT(8) struct ieee80211_txrx_data { struct sk_buff *skb; struct net_device *dev; @@ -419,7 +420,7 @@ struct ieee80211_local { struct net_device *mdev; /* wmaster# - "master" 802.11 device */ int open_count; - int monitors; + int monitors, cooked_mntrs; /* number of interfaces with corresponding FIF_ flags */ int fif_fcsfail, fif_plcpfail, fif_control, fif_other_bss; unsigned int filter_flags; /* FIF_* */ diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c index 3a3112f178..b1fc112152 100644 --- a/net/mac80211/rx.c +++ b/net/mac80211/rx.c @@ -223,6 +223,9 @@ ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb, if (sdata->vif.type != IEEE80211_IF_TYPE_MNTR) continue; + if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) + continue; + if (prev_dev) { skb2 = skb_clone(skb, GFP_ATOMIC); if (skb2) { @@ -1520,6 +1523,86 @@ static void ieee80211_rx_michael_mic_report(struct net_device *dev, rx->skb = NULL; } +static void ieee80211_rx_cooked_monitor(struct ieee80211_txrx_data *rx) +{ + struct ieee80211_sub_if_data *sdata; + struct ieee80211_local *local = rx->local; + struct ieee80211_rtap_hdr { + struct ieee80211_radiotap_header hdr; + u8 flags; + u8 rate; + __le16 chan_freq; + __le16 chan_flags; + } __attribute__ ((packed)) *rthdr; + struct sk_buff *skb = rx->skb, *skb2; + struct net_device *prev_dev = NULL; + struct ieee80211_rx_status *status = rx->u.rx.status; + + if (rx->flags & IEEE80211_TXRXD_RX_CMNTR_REPORTED) + goto out_free_skb; + + if (skb_headroom(skb) < sizeof(*rthdr) && + pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC)) + goto out_free_skb; + + rthdr = (void *)skb_push(skb, sizeof(*rthdr)); + memset(rthdr, 0, sizeof(*rthdr)); + rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr)); + rthdr->hdr.it_present = + cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) | + (1 << IEEE80211_RADIOTAP_RATE) | + (1 << IEEE80211_RADIOTAP_CHANNEL)); + + rthdr->rate = rx->u.rx.rate->bitrate / 5; + rthdr->chan_freq = cpu_to_le16(status->freq); + + if (status->band == IEEE80211_BAND_5GHZ) + rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM | + IEEE80211_CHAN_5GHZ); + else + rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN | + IEEE80211_CHAN_2GHZ); + + skb_set_mac_header(skb, 0); + skb->ip_summed = CHECKSUM_UNNECESSARY; + skb->pkt_type = PACKET_OTHERHOST; + skb->protocol = htons(ETH_P_802_2); + + list_for_each_entry_rcu(sdata, &local->interfaces, list) { + if (!netif_running(sdata->dev)) + continue; + + if (sdata->vif.type != IEEE80211_IF_TYPE_MNTR || + !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)) + continue; + + if (prev_dev) { + skb2 = skb_clone(skb, GFP_ATOMIC); + if (skb2) { + skb2->dev = prev_dev; + netif_rx(skb2); + } + } + + prev_dev = sdata->dev; + sdata->dev->stats.rx_packets++; + sdata->dev->stats.rx_bytes += skb->len; + } + + if (prev_dev) { + skb->dev = prev_dev; + netif_rx(skb); + skb = NULL; + } else + goto out_free_skb; + + rx->flags |= IEEE80211_TXRXD_RX_CMNTR_REPORTED; + return; + + out_free_skb: + dev_kfree_skb(skb); +} + typedef ieee80211_rx_result (*ieee80211_rx_handler)(struct ieee80211_txrx_data *); static ieee80211_rx_handler ieee80211_rx_handlers[] = { @@ -1574,9 +1657,11 @@ static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata, } switch (res) { + case RX_CONTINUE: case RX_DROP_MONITOR: + ieee80211_rx_cooked_monitor(rx); + break; case RX_DROP_UNUSABLE: - case RX_CONTINUE: dev_kfree_skb(rx->skb); break; }