Return-path: Received: from smtp.rutgers.edu ([128.6.72.243]:9477 "EHLO annwn14.rutgers.edu" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1161377AbXDWS6S (ORCPT ); Mon, 23 Apr 2007 14:58:18 -0400 From: Michael Wu Subject: [PATCH 01/13] mac80211: Add radiotap support Date: Mon, 23 Apr 2007 14:48:12 -0400 To: Jiri Benc Cc: linux-wireless@vger.kernel.org, John Linville Message-Id: <20070423184811.7029.24949.stgit@magic.sourmilk.net> Content-Type: text/plain; charset=utf-8; format=fixed Sender: linux-wireless-owner@vger.kernel.org List-ID: From: Michael Wu This patch makes mac80211 monitor interfaces use radiotap headers. It also provides a bit to let a driver specify a frame has a radiotap header and another bit to let the driver know if adding a radiotap header would be helpful. Thanks to Andy Green for testing earlier versions of this patch. Signed-off-by: Michael Wu --- include/net/mac80211.h | 8 +++- net/mac80211/ieee80211.c | 75 ++++++++++++++++++++++++++++++++++------ net/mac80211/ieee80211_iface.c | 2 + 3 files changed, 70 insertions(+), 15 deletions(-) diff --git a/include/net/mac80211.h b/include/net/mac80211.h index 1fb4bd9..6392c44 100644 --- a/include/net/mac80211.h +++ b/include/net/mac80211.h @@ -216,9 +216,6 @@ struct ieee80211_tx_control { int ifindex; /* internal */ }; -#define RX_FLAG_MMIC_ERROR 0x1 -#define RX_FLAG_DECRYPTED 0x2 - /* Receive status. The low-level driver should provide this information * (the subset supported by hardware) to the 802.11 code with each received * frame. */ @@ -232,6 +229,9 @@ struct ieee80211_rx_status { int noise; int antenna; int rate; +#define RX_FLAG_MMIC_ERROR (1<<0) +#define RX_FLAG_DECRYPTED (1<<1) +#define RX_FLAG_RADIOTAP (1<<2) int flag; }; @@ -278,6 +278,8 @@ struct ieee80211_conf { #define IEEE80211_CONF_SHORT_SLOT_TIME (1<<0) /* use IEEE 802.11g Short Slot * Time */ #define IEEE80211_CONF_SSID_HIDDEN (1<<1) /* do not broadcast the ssid */ +#define IEEE80211_CONF_RADIOTAP (1<<2) /* use radiotap if supported + check this bit at RX time */ u32 flags; /* configuration flags defined above */ u8 power_level; /* transmit power limit for current diff --git a/net/mac80211/ieee80211.c b/net/mac80211/ieee80211.c index ab51a74..51ad624 100644 --- a/net/mac80211/ieee80211.c +++ b/net/mac80211/ieee80211.c @@ -8,6 +8,7 @@ */ #include +#include #include #include #include @@ -291,6 +292,14 @@ int ieee80211_get_hdrlen_from_skb(const struct sk_buff *skb) } EXPORT_SYMBOL(ieee80211_get_hdrlen_from_skb); +static int ieee80211_get_radiotap_len(struct sk_buff *skb) +{ + struct ieee80211_radiotap_header *hdr = + (struct ieee80211_radiotap_header *) skb->data; + + return le16_to_cpu(hdr->it_len); +} + #ifdef CONFIG_MAC80211_LOWTX_FRAME_DUMP static void ieee80211_dump_frame(const char *ifname, const char *title, const struct sk_buff *skb) @@ -2355,6 +2364,7 @@ static int ieee80211_open(struct net_device *dev) /* run the interface in a "soft monitor" mode */ local->monitors++; local->open_count++; + local->hw.conf.flags |= IEEE80211_CONF_RADIOTAP; return 0; } ieee80211_start_soft_monitor(local); @@ -2403,9 +2413,10 @@ static int ieee80211_open(struct net_device *dev) } local->open_count++; - if (sdata->type == IEEE80211_IF_TYPE_MNTR) + if (sdata->type == IEEE80211_IF_TYPE_MNTR) { local->monitors++; - else + local->hw.conf.flags |= IEEE80211_CONF_RADIOTAP; + } else ieee80211_if_config(dev); if (sdata->type == IEEE80211_IF_TYPE_STA && @@ -2430,13 +2441,18 @@ static int ieee80211_stop(struct net_device *dev) /* remove "soft monitor" interface */ local->open_count--; local->monitors--; + if (!local->monitors) + local->hw.conf.flags &= ~IEEE80211_CONF_RADIOTAP; return 0; } netif_stop_queue(dev); - if (sdata->type == IEEE80211_IF_TYPE_MNTR) + if (sdata->type == IEEE80211_IF_TYPE_MNTR) { local->monitors--; + if (!local->monitors) + local->hw.conf.flags &= ~IEEE80211_CONF_RADIOTAP; + } local->open_count--; if (local->open_count == 0) { @@ -2782,26 +2798,53 @@ ieee80211_rx_monitor(struct net_device *dev, struct sk_buff *skb, struct ieee80211_rx_status *status) { struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr); - struct ieee80211_frame_info *fi; struct ieee80211_sub_if_data *sdata; - const size_t hlen = sizeof(struct ieee80211_frame_info) - - sizeof(fi->msg_type); + struct ieee80211_rate *rate; + struct ieee80211_rtap_hdr { + struct ieee80211_radiotap_header hdr; + u8 flags; + u8 rate; + __le16 chan_freq; + __le16 chan_flags; + u8 antsignal; + } __attribute__ ((packed)) *rthdr; skb->dev = dev; sdata = IEEE80211_DEV_TO_SUB_IF(dev); - if (skb_headroom(skb) < hlen) { + if (status->flag & RX_FLAG_RADIOTAP) + goto out; + + if (skb_headroom(skb) < sizeof(*rthdr)) { I802_DEBUG_INC(local->rx_expand_skb_head); - if (pskb_expand_head(skb, hlen, 0, GFP_ATOMIC)) { + if (pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC)) { dev_kfree_skb(skb); return; } } - fi = (struct ieee80211_frame_info *) skb_push(skb, hlen); + rthdr = (struct ieee80211_rtap_hdr *) 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) | + (1 << IEEE80211_RADIOTAP_DB_ANTSIGNAL)); + rthdr->flags = local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS ? + IEEE80211_RADIOTAP_F_FCS : 0; + rate = ieee80211_get_rate(local, status->phymode, status->rate); + if (rate) + rthdr->rate = rate->rate / 5; + rthdr->chan_freq = cpu_to_le16(status->freq); + rthdr->chan_flags = + status->phymode == MODE_IEEE80211A ? + cpu_to_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ) : + cpu_to_le16(IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ); + rthdr->antsignal = status->ssi; - ieee80211_fill_frame_info(local, fi, status); + out: sdata->stats.rx_packets++; sdata->stats.rx_bytes += skb->len; @@ -3397,6 +3440,9 @@ ieee80211_rx_h_sta_process(struct ieee80211_txrx_data *rx) return TXRX_QUEUED; } + if (rx->u.rx.status->flag & RX_FLAG_RADIOTAP) + skb_pull(rx->skb, ieee80211_get_radiotap_len(rx->skb)); + return TXRX_CONTINUE; } @@ -3772,6 +3818,12 @@ void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb, struct ieee80211_txrx_data rx; u16 type; int multicast; + int radiotap_len = 0; + + if (status->flag & RX_FLAG_RADIOTAP) { + radiotap_len = ieee80211_get_radiotap_len(skb); + skb_pull(skb, radiotap_len); + } hdr = (struct ieee80211_hdr *) skb->data; memset(&rx, 0, sizeof(rx)); @@ -3808,6 +3860,7 @@ void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb, goto end; skb = rx.skb; + skb_push(skb, radiotap_len); if (sta && !sta->assoc_ap && !(sta->flags & WLAN_STA_WDS) && !local->iff_promiscs && !multicast) { rx.u.rx.ra_match = 1; @@ -3816,7 +3869,7 @@ void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb, } else { struct ieee80211_sub_if_data *prev = NULL; struct sk_buff *skb_new; - u8 *bssid = ieee80211_get_bssid(hdr, skb->len); + u8 *bssid = ieee80211_get_bssid(hdr, skb->len - radiotap_len); list_for_each_entry(sdata, &local->sub_if_list, list) { rx.u.rx.ra_match = 1; diff --git a/net/mac80211/ieee80211_iface.c b/net/mac80211/ieee80211_iface.c index b1b20ba..495177b 100644 --- a/net/mac80211/ieee80211_iface.c +++ b/net/mac80211/ieee80211_iface.c @@ -192,7 +192,7 @@ void ieee80211_if_set_type(struct net_device *dev, int type) break; } case IEEE80211_IF_TYPE_MNTR: - dev->type = ARPHRD_IEEE80211_PRISM; + dev->type = ARPHRD_IEEE80211_RADIOTAP; break; default: printk(KERN_WARNING "%s: %s: Unknown interface type 0x%x",