Add HostAP wireless driver.

Includes minor cleanups from Adrian Bunk <bunk@stusta.de>.
diff --git a/drivers/net/wireless/hostap/hostap_80211_tx.c b/drivers/net/wireless/hostap/hostap_80211_tx.c
new file mode 100644
index 0000000..8a94a80
--- /dev/null
+++ b/drivers/net/wireless/hostap/hostap_80211_tx.c
@@ -0,0 +1,522 @@
+void hostap_dump_tx_80211(const char *name, struct sk_buff *skb)
+{
+	struct hostap_ieee80211_hdr *hdr;
+	u16 fc;
+
+	hdr = (struct hostap_ieee80211_hdr *) skb->data;
+
+	printk(KERN_DEBUG "%s: TX len=%d jiffies=%ld\n",
+	       name, skb->len, jiffies);
+
+	if (skb->len < 2)
+		return;
+
+	fc = le16_to_cpu(hdr->frame_control);
+	printk(KERN_DEBUG "   FC=0x%04x (type=%d:%d)%s%s",
+	       fc, WLAN_FC_GET_TYPE(fc), WLAN_FC_GET_STYPE(fc),
+	       fc & WLAN_FC_TODS ? " [ToDS]" : "",
+	       fc & WLAN_FC_FROMDS ? " [FromDS]" : "");
+
+	if (skb->len < IEEE80211_DATA_HDR3_LEN) {
+		printk("\n");
+		return;
+	}
+
+	printk(" dur=0x%04x seq=0x%04x\n", le16_to_cpu(hdr->duration_id),
+	       le16_to_cpu(hdr->seq_ctrl));
+
+	printk(KERN_DEBUG "   A1=" MACSTR " A2=" MACSTR " A3=" MACSTR,
+	       MAC2STR(hdr->addr1), MAC2STR(hdr->addr2), MAC2STR(hdr->addr3));
+	if (skb->len >= 30)
+		printk(" A4=" MACSTR, MAC2STR(hdr->addr4));
+	printk("\n");
+}
+
+
+/* hard_start_xmit function for data interfaces (wlan#, wlan#wds#, wlan#sta)
+ * Convert Ethernet header into a suitable IEEE 802.11 header depending on
+ * device configuration. */
+int hostap_data_start_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct hostap_interface *iface;
+	local_info_t *local;
+	int need_headroom, need_tailroom = 0;
+	struct hostap_ieee80211_hdr hdr;
+	u16 fc, ethertype = 0;
+	enum {
+		WDS_NO = 0, WDS_OWN_FRAME, WDS_COMPLIANT_FRAME
+	} use_wds = WDS_NO;
+	u8 *encaps_data;
+	int hdr_len, encaps_len, skip_header_bytes;
+	int to_assoc_ap = 0;
+	struct hostap_skb_tx_data *meta;
+
+	iface = netdev_priv(dev);
+	local = iface->local;
+
+	if (skb->len < ETH_HLEN) {
+		printk(KERN_DEBUG "%s: hostap_data_start_xmit: short skb "
+		       "(len=%d)\n", dev->name, skb->len);
+		kfree_skb(skb);
+		return 0;
+	}
+
+	if (local->ddev != dev) {
+		use_wds = (local->iw_mode == IW_MODE_MASTER &&
+			   !(local->wds_type & HOSTAP_WDS_STANDARD_FRAME)) ?
+			WDS_OWN_FRAME : WDS_COMPLIANT_FRAME;
+		if (dev == local->stadev) {
+			to_assoc_ap = 1;
+			use_wds = WDS_NO;
+		} else if (dev == local->apdev) {
+			printk(KERN_DEBUG "%s: prism2_tx: trying to use "
+			       "AP device with Ethernet net dev\n", dev->name);
+			kfree_skb(skb);
+			return 0;
+		}
+	} else {
+		if (local->iw_mode == IW_MODE_REPEAT) {
+			printk(KERN_DEBUG "%s: prism2_tx: trying to use "
+			       "non-WDS link in Repeater mode\n", dev->name);
+			kfree_skb(skb);
+			return 0;
+		} else if (local->iw_mode == IW_MODE_INFRA &&
+			   (local->wds_type & HOSTAP_WDS_AP_CLIENT) &&
+			   memcmp(skb->data + ETH_ALEN, dev->dev_addr,
+				  ETH_ALEN) != 0) {
+			/* AP client mode: send frames with foreign src addr
+			 * using 4-addr WDS frames */
+			use_wds = WDS_COMPLIANT_FRAME;
+		}
+	}
+
+	/* Incoming skb->data: dst_addr[6], src_addr[6], proto[2], payload
+	 * ==>
+	 * Prism2 TX frame with 802.11 header:
+	 * txdesc (address order depending on used mode; includes dst_addr and
+	 * src_addr), possible encapsulation (RFC1042/Bridge-Tunnel;
+	 * proto[2], payload {, possible addr4[6]} */
+
+	ethertype = (skb->data[12] << 8) | skb->data[13];
+
+	memset(&hdr, 0, sizeof(hdr));
+
+	/* Length of data after IEEE 802.11 header */
+	encaps_data = NULL;
+	encaps_len = 0;
+	skip_header_bytes = ETH_HLEN;
+	if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
+		encaps_data = bridge_tunnel_header;
+		encaps_len = sizeof(bridge_tunnel_header);
+		skip_header_bytes -= 2;
+	} else if (ethertype >= 0x600) {
+		encaps_data = rfc1042_header;
+		encaps_len = sizeof(rfc1042_header);
+		skip_header_bytes -= 2;
+	}
+
+	fc = (WLAN_FC_TYPE_DATA << 2) | (WLAN_FC_STYPE_DATA << 4);
+	hdr_len = IEEE80211_DATA_HDR3_LEN;
+
+	if (use_wds != WDS_NO) {
+		/* Note! Prism2 station firmware has problems with sending real
+		 * 802.11 frames with four addresses; until these problems can
+		 * be fixed or worked around, 4-addr frames needed for WDS are
+		 * using incompatible format: FromDS flag is not set and the
+		 * fourth address is added after the frame payload; it is
+		 * assumed, that the receiving station knows how to handle this
+		 * frame format */
+
+		if (use_wds == WDS_COMPLIANT_FRAME) {
+			fc |= WLAN_FC_FROMDS | WLAN_FC_TODS;
+			/* From&To DS: Addr1 = RA, Addr2 = TA, Addr3 = DA,
+			 * Addr4 = SA */
+			memcpy(&hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
+			hdr_len += ETH_ALEN;
+		} else {
+			/* bogus 4-addr format to workaround Prism2 station
+			 * f/w bug */
+			fc |= WLAN_FC_TODS;
+			/* From DS: Addr1 = DA (used as RA),
+			 * Addr2 = BSSID (used as TA), Addr3 = SA (used as DA),
+			 */
+
+			/* SA from skb->data + ETH_ALEN will be added after
+			 * frame payload; use hdr.addr4 as a temporary buffer
+			 */
+			memcpy(&hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
+			need_tailroom += ETH_ALEN;
+		}
+
+		/* send broadcast and multicast frames to broadcast RA, if
+		 * configured; otherwise, use unicast RA of the WDS link */
+		if ((local->wds_type & HOSTAP_WDS_BROADCAST_RA) &&
+		    skb->data[0] & 0x01)
+			memset(&hdr.addr1, 0xff, ETH_ALEN);
+		else if (iface->type == HOSTAP_INTERFACE_WDS)
+			memcpy(&hdr.addr1, iface->u.wds.remote_addr,
+			       ETH_ALEN);
+		else
+			memcpy(&hdr.addr1, local->bssid, ETH_ALEN);
+		memcpy(&hdr.addr2, dev->dev_addr, ETH_ALEN);
+		memcpy(&hdr.addr3, skb->data, ETH_ALEN);
+	} else if (local->iw_mode == IW_MODE_MASTER && !to_assoc_ap) {
+		fc |= WLAN_FC_FROMDS;
+		/* From DS: Addr1 = DA, Addr2 = BSSID, Addr3 = SA */
+		memcpy(&hdr.addr1, skb->data, ETH_ALEN);
+		memcpy(&hdr.addr2, dev->dev_addr, ETH_ALEN);
+		memcpy(&hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN);
+	} else if (local->iw_mode == IW_MODE_INFRA || to_assoc_ap) {
+		fc |= WLAN_FC_TODS;
+		/* To DS: Addr1 = BSSID, Addr2 = SA, Addr3 = DA */
+		memcpy(&hdr.addr1, to_assoc_ap ?
+		       local->assoc_ap_addr : local->bssid, ETH_ALEN);
+		memcpy(&hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
+		memcpy(&hdr.addr3, skb->data, ETH_ALEN);
+	} else if (local->iw_mode == IW_MODE_ADHOC) {
+		/* not From/To DS: Addr1 = DA, Addr2 = SA, Addr3 = BSSID */
+		memcpy(&hdr.addr1, skb->data, ETH_ALEN);
+		memcpy(&hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
+		memcpy(&hdr.addr3, local->bssid, ETH_ALEN);
+	}
+
+	hdr.frame_control = cpu_to_le16(fc);
+
+	skb_pull(skb, skip_header_bytes);
+	need_headroom = local->func->need_tx_headroom + hdr_len + encaps_len;
+	if (skb_tailroom(skb) < need_tailroom) {
+		skb = skb_unshare(skb, GFP_ATOMIC);
+		if (skb == NULL) {
+			iface->stats.tx_dropped++;
+			return 0;
+		}
+		if (pskb_expand_head(skb, need_headroom, need_tailroom,
+				     GFP_ATOMIC)) {
+			kfree_skb(skb);
+			iface->stats.tx_dropped++;
+			return 0;
+		}
+	} else if (skb_headroom(skb) < need_headroom) {
+		struct sk_buff *tmp = skb;
+		skb = skb_realloc_headroom(skb, need_headroom);
+		kfree_skb(tmp);
+		if (skb == NULL) {
+			iface->stats.tx_dropped++;
+			return 0;
+		}
+	} else {
+		skb = skb_unshare(skb, GFP_ATOMIC);
+		if (skb == NULL) {
+			iface->stats.tx_dropped++;
+			return 0;
+		}
+	}
+
+	if (encaps_data)
+		memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
+	memcpy(skb_push(skb, hdr_len), &hdr, hdr_len);
+	if (use_wds == WDS_OWN_FRAME) {
+		memcpy(skb_put(skb, ETH_ALEN), &hdr.addr4, ETH_ALEN);
+	}
+
+	iface->stats.tx_packets++;
+	iface->stats.tx_bytes += skb->len;
+
+	skb->mac.raw = skb->data;
+	meta = (struct hostap_skb_tx_data *) skb->cb;
+	memset(meta, 0, sizeof(*meta));
+	meta->magic = HOSTAP_SKB_TX_DATA_MAGIC;
+	meta->wds = use_wds;
+	meta->ethertype = ethertype;
+	meta->iface = iface;
+
+	/* Send IEEE 802.11 encapsulated frame using the master radio device */
+	skb->dev = local->dev;
+	dev_queue_xmit(skb);
+	return 0;
+}
+
+
+/* hard_start_xmit function for hostapd wlan#ap interfaces */
+int hostap_mgmt_start_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct hostap_interface *iface;
+	local_info_t *local;
+	struct hostap_skb_tx_data *meta;
+	struct hostap_ieee80211_hdr *hdr;
+	u16 fc;
+
+	iface = netdev_priv(dev);
+	local = iface->local;
+
+	if (skb->len < 10) {
+		printk(KERN_DEBUG "%s: hostap_mgmt_start_xmit: short skb "
+		       "(len=%d)\n", dev->name, skb->len);
+		kfree_skb(skb);
+		return 0;
+	}
+
+	iface->stats.tx_packets++;
+	iface->stats.tx_bytes += skb->len;
+
+	meta = (struct hostap_skb_tx_data *) skb->cb;
+	memset(meta, 0, sizeof(*meta));
+	meta->magic = HOSTAP_SKB_TX_DATA_MAGIC;
+	meta->iface = iface;
+
+	if (skb->len >= IEEE80211_DATA_HDR3_LEN + sizeof(rfc1042_header) + 2) {
+		hdr = (struct hostap_ieee80211_hdr *) skb->data;
+		fc = le16_to_cpu(hdr->frame_control);
+		if (WLAN_FC_GET_TYPE(fc) == WLAN_FC_TYPE_DATA &&
+		    WLAN_FC_GET_STYPE(fc) == WLAN_FC_STYPE_DATA) {
+			u8 *pos = &skb->data[IEEE80211_DATA_HDR3_LEN +
+					     sizeof(rfc1042_header)];
+			meta->ethertype = (pos[0] << 8) | pos[1];
+		}
+	}
+
+	/* Send IEEE 802.11 encapsulated frame using the master radio device */
+	skb->dev = local->dev;
+	dev_queue_xmit(skb);
+	return 0;
+}
+
+
+/* Called only from software IRQ */
+struct sk_buff * hostap_tx_encrypt(struct sk_buff *skb,
+				   struct prism2_crypt_data *crypt)
+{
+	struct hostap_interface *iface;
+	local_info_t *local;
+	struct hostap_ieee80211_hdr *hdr;
+	u16 fc;
+	int hdr_len, res;
+
+	iface = netdev_priv(skb->dev);
+	local = iface->local;
+
+	if (skb->len < IEEE80211_DATA_HDR3_LEN) {
+		kfree_skb(skb);
+		return NULL;
+	}
+
+	if (local->tkip_countermeasures &&
+	    crypt && crypt->ops && strcmp(crypt->ops->name, "TKIP") == 0) {
+		hdr = (struct hostap_ieee80211_hdr *) skb->data;
+		if (net_ratelimit()) {
+			printk(KERN_DEBUG "%s: TKIP countermeasures: dropped "
+			       "TX packet to " MACSTR "\n",
+			       local->dev->name, MAC2STR(hdr->addr1));
+		}
+		kfree_skb(skb);
+		return NULL;
+	}
+
+	skb = skb_unshare(skb, GFP_ATOMIC);
+	if (skb == NULL)
+		return NULL;
+
+	if ((skb_headroom(skb) < crypt->ops->extra_prefix_len ||
+	     skb_tailroom(skb) < crypt->ops->extra_postfix_len) &&
+	    pskb_expand_head(skb, crypt->ops->extra_prefix_len,
+			     crypt->ops->extra_postfix_len, GFP_ATOMIC)) {
+		kfree_skb(skb);
+		return NULL;
+	}
+
+	hdr = (struct hostap_ieee80211_hdr *) skb->data;
+ 	fc = le16_to_cpu(hdr->frame_control);
+	hdr_len = hostap_80211_get_hdrlen(fc);
+
+	/* Host-based IEEE 802.11 fragmentation for TX is not yet supported, so
+	 * call both MSDU and MPDU encryption functions from here. */
+	atomic_inc(&crypt->refcnt);
+	res = 0;
+	if (crypt->ops->encrypt_msdu)
+		res = crypt->ops->encrypt_msdu(skb, hdr_len, crypt->priv);
+	if (res == 0 && crypt->ops->encrypt_mpdu)
+		res = crypt->ops->encrypt_mpdu(skb, hdr_len, crypt->priv);
+	atomic_dec(&crypt->refcnt);
+	if (res < 0) {
+		kfree_skb(skb);
+		return NULL;
+	}
+
+	return skb;
+}
+
+
+/* hard_start_xmit function for master radio interface wifi#.
+ * AP processing (TX rate control, power save buffering, etc.).
+ * Use hardware TX function to send the frame. */
+int hostap_master_start_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct hostap_interface *iface;
+	local_info_t *local;
+	int ret = 1;
+	u16 fc;
+	struct hostap_tx_data tx;
+	ap_tx_ret tx_ret;
+	struct hostap_skb_tx_data *meta;
+	int no_encrypt = 0;
+	struct hostap_ieee80211_hdr *hdr;
+
+	iface = netdev_priv(dev);
+	local = iface->local;
+
+	tx.skb = skb;
+	tx.sta_ptr = NULL;
+
+	meta = (struct hostap_skb_tx_data *) skb->cb;
+	if (meta->magic != HOSTAP_SKB_TX_DATA_MAGIC) {
+		printk(KERN_DEBUG "%s: invalid skb->cb magic (0x%08x, "
+		       "expected 0x%08x)\n",
+		       dev->name, meta->magic, HOSTAP_SKB_TX_DATA_MAGIC);
+		ret = 0;
+		iface->stats.tx_dropped++;
+		goto fail;
+	}
+
+	if (local->host_encrypt) {
+		/* Set crypt to default algorithm and key; will be replaced in
+		 * AP code if STA has own alg/key */
+		tx.crypt = local->crypt[local->tx_keyidx];
+		tx.host_encrypt = 1;
+	} else {
+		tx.crypt = NULL;
+		tx.host_encrypt = 0;
+	}
+
+	if (skb->len < 24) {
+		printk(KERN_DEBUG "%s: hostap_master_start_xmit: short skb "
+		       "(len=%d)\n", dev->name, skb->len);
+		ret = 0;
+		iface->stats.tx_dropped++;
+		goto fail;
+	}
+
+	/* FIX (?):
+	 * Wi-Fi 802.11b test plan suggests that AP should ignore power save
+	 * bit in authentication and (re)association frames and assume tha
+	 * STA remains awake for the response. */
+	tx_ret = hostap_handle_sta_tx(local, &tx);
+	skb = tx.skb;
+	meta = (struct hostap_skb_tx_data *) skb->cb;
+	hdr = (struct hostap_ieee80211_hdr *) skb->data;
+ 	fc = le16_to_cpu(hdr->frame_control);
+	switch (tx_ret) {
+	case AP_TX_CONTINUE:
+		break;
+	case AP_TX_CONTINUE_NOT_AUTHORIZED:
+		if (local->ieee_802_1x &&
+		    WLAN_FC_GET_TYPE(fc) == WLAN_FC_TYPE_DATA &&
+		    meta->ethertype != ETH_P_PAE && !meta->wds) {
+			printk(KERN_DEBUG "%s: dropped frame to unauthorized "
+			       "port (IEEE 802.1X): ethertype=0x%04x\n",
+			       dev->name, meta->ethertype);
+			hostap_dump_tx_80211(dev->name, skb);
+
+			ret = 0; /* drop packet */
+			iface->stats.tx_dropped++;
+			goto fail;
+		}
+		break;
+	case AP_TX_DROP:
+		ret = 0; /* drop packet */
+		iface->stats.tx_dropped++;
+		goto fail;
+	case AP_TX_RETRY:
+		goto fail;
+	case AP_TX_BUFFERED:
+		/* do not free skb here, it will be freed when the
+		 * buffered frame is sent/timed out */
+		ret = 0;
+		goto tx_exit;
+	}
+
+	/* Request TX callback if protocol version is 2 in 802.11 header;
+	 * this version 2 is a special case used between hostapd and kernel
+	 * driver */
+	if (((fc & WLAN_FC_PVER) == BIT(1)) &&
+	    local->ap && local->ap->tx_callback_idx && meta->tx_cb_idx == 0) {
+		meta->tx_cb_idx = local->ap->tx_callback_idx;
+
+		/* remove special version from the frame header */
+		fc &= ~WLAN_FC_PVER;
+		hdr->frame_control = cpu_to_le16(fc);
+	}
+
+	if (WLAN_FC_GET_TYPE(fc) != WLAN_FC_TYPE_DATA) {
+		no_encrypt = 1;
+		tx.crypt = NULL;
+	}
+
+	if (local->ieee_802_1x && meta->ethertype == ETH_P_PAE && tx.crypt &&
+	    !(fc & WLAN_FC_ISWEP)) {
+		no_encrypt = 1;
+		PDEBUG(DEBUG_EXTRA2, "%s: TX: IEEE 802.1X - passing "
+		       "unencrypted EAPOL frame\n", dev->name);
+		tx.crypt = NULL; /* no encryption for IEEE 802.1X frames */
+	}
+
+	if (tx.crypt && (!tx.crypt->ops || !tx.crypt->ops->encrypt_mpdu))
+		tx.crypt = NULL;
+	else if ((tx.crypt || local->crypt[local->tx_keyidx]) && !no_encrypt) {
+		/* Add ISWEP flag both for firmware and host based encryption
+		 */
+		fc |= WLAN_FC_ISWEP;
+		hdr->frame_control = cpu_to_le16(fc);
+	} else if (local->drop_unencrypted &&
+		   WLAN_FC_GET_TYPE(fc) == WLAN_FC_TYPE_DATA &&
+		   meta->ethertype != ETH_P_PAE) {
+		if (net_ratelimit()) {
+			printk(KERN_DEBUG "%s: dropped unencrypted TX data "
+			       "frame (drop_unencrypted=1)\n", dev->name);
+		}
+		iface->stats.tx_dropped++;
+		ret = 0;
+		goto fail;
+	}
+
+	if (tx.crypt) {
+		skb = hostap_tx_encrypt(skb, tx.crypt);
+		if (skb == NULL) {
+			printk(KERN_DEBUG "%s: TX - encryption failed\n",
+			       dev->name);
+			ret = 0;
+			goto fail;
+		}
+		meta = (struct hostap_skb_tx_data *) skb->cb;
+		if (meta->magic != HOSTAP_SKB_TX_DATA_MAGIC) {
+			printk(KERN_DEBUG "%s: invalid skb->cb magic (0x%08x, "
+			       "expected 0x%08x) after hostap_tx_encrypt\n",
+			       dev->name, meta->magic,
+			       HOSTAP_SKB_TX_DATA_MAGIC);
+			ret = 0;
+			iface->stats.tx_dropped++;
+			goto fail;
+		}
+	}
+
+	if (local->func->tx == NULL || local->func->tx(skb, dev)) {
+		ret = 0;
+		iface->stats.tx_dropped++;
+	} else {
+		ret = 0;
+		iface->stats.tx_packets++;
+		iface->stats.tx_bytes += skb->len;
+	}
+
+ fail:
+	if (!ret && skb)
+		dev_kfree_skb(skb);
+ tx_exit:
+	if (tx.sta_ptr)
+		hostap_handle_sta_release(tx.sta_ptr);
+	return ret;
+}
+
+
+EXPORT_SYMBOL(hostap_dump_tx_80211);
+EXPORT_SYMBOL(hostap_tx_encrypt);
+EXPORT_SYMBOL(hostap_master_start_xmit);