--- /dev/null
+/******************************************************************************
+
+ Copyright(c) 2003 - 2005 Intel Corporation. All rights reserved.
+
+ This program is free software; you can redistribute it and/or modify it
+ under the terms of version 2 of the GNU General Public License as
+ published by the Free Software Foundation.
+
+ This program is distributed in the hope that it will be useful, but WITHOUT
+ ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ more details.
+
+ You should have received a copy of the GNU General Public License along with
+ this program; if not, write to the Free Software Foundation, Inc., 59
+ Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+ The full GNU General Public License is included in this distribution in the
+ file called LICENSE.
+
+ Contact Information:
+ Intel Linux Wireless <ilw@linux.intel.com>
+ Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
+
+******************************************************************************/
+#include <linux/compiler.h>
+#include <linux/errno.h>
+#include <linux/if_arp.h>
+#include <linux/in6.h>
+#include <linux/in.h>
+#include <linux/ip.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/proc_fs.h>
+#include <linux/skbuff.h>
+#include <linux/slab.h>
+#include <linux/tcp.h>
+#include <linux/types.h>
+#include <linux/wireless.h>
+#include <linux/etherdevice.h>
+#include <asm/uaccess.h>
+
+#include "libipw.h"
+
+/*
+
+802.11 Data Frame
+
+ ,-------------------------------------------------------------------.
+Bytes | 2 | 2 | 6 | 6 | 6 | 2 | 0..2312 | 4 |
+ |------|------|---------|---------|---------|------|---------|------|
+Desc. | ctrl | dura | DA/RA | TA | SA | Sequ | Frame | fcs |
+ | | tion | (BSSID) | | | ence | data | |
+ `--------------------------------------------------| |------'
+Total: 28 non-data bytes `----.----'
+ |
+ .- 'Frame data' expands, if WEP enabled, to <----------'
+ |
+ V
+ ,-----------------------.
+Bytes | 4 | 0-2296 | 4 |
+ |-----|-----------|-----|
+Desc. | IV | Encrypted | ICV |
+ | | Packet | |
+ `-----| |-----'
+ `-----.-----'
+ |
+ .- 'Encrypted Packet' expands to
+ |
+ V
+ ,---------------------------------------------------.
+Bytes | 1 | 1 | 1 | 3 | 2 | 0-2304 |
+ |------|------|---------|----------|------|---------|
+Desc. | SNAP | SNAP | Control |Eth Tunnel| Type | IP |
+ | DSAP | SSAP | | | | Packet |
+ | 0xAA | 0xAA |0x03 (UI)|0x00-00-F8| | |
+ `----------------------------------------------------
+Total: 8 non-data bytes
+
+802.3 Ethernet Data Frame
+
+ ,-----------------------------------------.
+Bytes | 6 | 6 | 2 | Variable | 4 |
+ |-------|-------|------|-----------|------|
+Desc. | Dest. | Source| Type | IP Packet | fcs |
+ | MAC | MAC | | | |
+ `-----------------------------------------'
+Total: 18 non-data bytes
+
+In the event that fragmentation is required, the incoming payload is split into
+N parts of size ieee->fts. The first fragment contains the SNAP header and the
+remaining packets are just data.
+
+If encryption is enabled, each fragment payload size is reduced by enough space
+to add the prefix and postfix (IV and ICV totalling 8 bytes in the case of WEP)
+So if you have 1500 bytes of payload with ieee->fts set to 500 without
+encryption it will take 3 frames. With WEP it will take 4 frames as the
+payload of each frame is reduced to 492 bytes.
+
+* SKB visualization
+*
+* ,- skb->data
+* |
+* | ETHERNET HEADER ,-<-- PAYLOAD
+* | | 14 bytes from skb->data
+* | 2 bytes for Type --> ,T. | (sizeof ethhdr)
+* | | | |
+* |,-Dest.--. ,--Src.---. | | |
+* | 6 bytes| | 6 bytes | | | |
+* v | | | | | |
+* 0 | v 1 | v | v 2
+* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+* ^ | ^ | ^ |
+* | | | | | |
+* | | | | `T' <---- 2 bytes for Type
+* | | | |
+* | | '---SNAP--' <-------- 6 bytes for SNAP
+* | |
+* `-IV--' <-------------------- 4 bytes for IV (WEP)
+*
+* SNAP HEADER
+*
+*/
+
+static u8 P802_1H_OUI[P80211_OUI_LEN] = { 0x00, 0x00, 0xf8 };
+static u8 RFC1042_OUI[P80211_OUI_LEN] = { 0x00, 0x00, 0x00 };
+
+static int libipw_copy_snap(u8 * data, __be16 h_proto)
+{
+ struct libipw_snap_hdr *snap;
+ u8 *oui;
+
+ snap = (struct libipw_snap_hdr *)data;
+ snap->dsap = 0xaa;
+ snap->ssap = 0xaa;
+ snap->ctrl = 0x03;
+
+ if (h_proto == htons(ETH_P_AARP) || h_proto == htons(ETH_P_IPX))
+ oui = P802_1H_OUI;
+ else
+ oui = RFC1042_OUI;
+ snap->oui[0] = oui[0];
+ snap->oui[1] = oui[1];
+ snap->oui[2] = oui[2];
+
+ memcpy(data + SNAP_SIZE, &h_proto, sizeof(u16));
+
+ return SNAP_SIZE + sizeof(u16);
+}
+
+static int libipw_encrypt_fragment(struct libipw_device *ieee,
+ struct sk_buff *frag, int hdr_len)
+{
+ struct lib80211_crypt_data *crypt =
+ ieee->crypt_info.crypt[ieee->crypt_info.tx_keyidx];
+ int res;
+
+ if (crypt == NULL)
+ return -1;
+
+ /* To encrypt, frame format is:
+ * IV (4 bytes), clear payload (including SNAP), ICV (4 bytes) */
+ atomic_inc(&crypt->refcnt);
+ res = 0;
+ if (crypt->ops && crypt->ops->encrypt_mpdu)
+ res = crypt->ops->encrypt_mpdu(frag, hdr_len, crypt->priv);
+
+ atomic_dec(&crypt->refcnt);
+ if (res < 0) {
+ printk(KERN_INFO "%s: Encryption failed: len=%d.\n",
+ ieee->dev->name, frag->len);
+ ieee->ieee_stats.tx_discards++;
+ return -1;
+ }
+
+ return 0;
+}
+
+void libipw_txb_free(struct libipw_txb *txb)
+{
+ int i;
+ if (unlikely(!txb))
+ return;
+ for (i = 0; i < txb->nr_frags; i++)
+ if (txb->fragments[i])
+ dev_kfree_skb_any(txb->fragments[i]);
+ kfree(txb);
+}
+
+static struct libipw_txb *libipw_alloc_txb(int nr_frags, int txb_size,
+ int headroom, gfp_t gfp_mask)
+{
+ struct libipw_txb *txb;
+ int i;
+ txb = kmalloc(sizeof(struct libipw_txb) + (sizeof(u8 *) * nr_frags),
+ gfp_mask);
+ if (!txb)
+ return NULL;
+
+ memset(txb, 0, sizeof(struct libipw_txb));
+ txb->nr_frags = nr_frags;
+ txb->frag_size = txb_size;
+
+ for (i = 0; i < nr_frags; i++) {
+ txb->fragments[i] = __dev_alloc_skb(txb_size + headroom,
+ gfp_mask);
+ if (unlikely(!txb->fragments[i])) {
+ i--;
+ break;
+ }
+ skb_reserve(txb->fragments[i], headroom);
+ }
+ if (unlikely(i != nr_frags)) {
+ while (i >= 0)
+ dev_kfree_skb_any(txb->fragments[i--]);
+ kfree(txb);
+ return NULL;
+ }
+ return txb;
+}
+
+static int libipw_classify(struct sk_buff *skb)
+{
+ struct ethhdr *eth;
+ struct iphdr *ip;
+
+ eth = (struct ethhdr *)skb->data;
+ if (eth->h_proto != htons(ETH_P_IP))
+ return 0;
+
+ ip = ip_hdr(skb);
+ switch (ip->tos & 0xfc) {
+ case 0x20:
+ return 2;
+ case 0x40:
+ return 1;
+ case 0x60:
+ return 3;
+ case 0x80:
+ return 4;
+ case 0xa0:
+ return 5;
+ case 0xc0:
+ return 6;
+ case 0xe0:
+ return 7;
+ default:
+ return 0;
+ }
+}
+
+/* Incoming skb is converted to a txb which consists of
+ * a block of 802.11 fragment packets (stored as skbs) */
+netdev_tx_t libipw_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+ struct libipw_device *ieee = netdev_priv(dev);
+ struct libipw_txb *txb = NULL;
+ struct libipw_hdr_3addrqos *frag_hdr;
+ int i, bytes_per_frag, nr_frags, bytes_last_frag, frag_size,
+ rts_required;
+ unsigned long flags;
+ int encrypt, host_encrypt, host_encrypt_msdu;
+ __be16 ether_type;
+ int bytes, fc, hdr_len;
+ struct sk_buff *skb_frag;
+ struct libipw_hdr_3addrqos header = {/* Ensure zero initialized */
+ .duration_id = 0,
+ .seq_ctl = 0,
+ .qos_ctl = 0
+ };
+ u8 dest[ETH_ALEN], src[ETH_ALEN];
+ struct lib80211_crypt_data *crypt;
+ int priority = skb->priority;
+ int snapped = 0;
+
+ if (ieee->is_queue_full && (*ieee->is_queue_full) (dev, priority))
+ return NETDEV_TX_BUSY;
+
+ spin_lock_irqsave(&ieee->lock, flags);
+
+ /* If there is no driver handler to take the TXB, dont' bother
+ * creating it... */
+ if (!ieee->hard_start_xmit) {
+ printk(KERN_WARNING "%s: No xmit handler.\n", ieee->dev->name);
+ goto success;
+ }
+
+ if (unlikely(skb->len < SNAP_SIZE + sizeof(u16))) {
+ printk(KERN_WARNING "%s: skb too small (%d).\n",
+ ieee->dev->name, skb->len);
+ goto success;
+ }
+
+ ether_type = ((struct ethhdr *)skb->data)->h_proto;
+
+ crypt = ieee->crypt_info.crypt[ieee->crypt_info.tx_keyidx];
+
+ encrypt = !(ether_type == htons(ETH_P_PAE) && ieee->ieee802_1x) &&
+ ieee->sec.encrypt;
+
+ host_encrypt = ieee->host_encrypt && encrypt && crypt;
+ host_encrypt_msdu = ieee->host_encrypt_msdu && encrypt && crypt;
+
+ if (!encrypt && ieee->ieee802_1x &&
+ ieee->drop_unencrypted && ether_type != htons(ETH_P_PAE)) {
+ dev->stats.tx_dropped++;
+ goto success;
+ }
+
+ /* Save source and destination addresses */
+ skb_copy_from_linear_data(skb, dest, ETH_ALEN);
+ skb_copy_from_linear_data_offset(skb, ETH_ALEN, src, ETH_ALEN);
+
+ if (host_encrypt)
+ fc = IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA |
+ IEEE80211_FCTL_PROTECTED;
+ else
+ fc = IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA;
+
+ if (ieee->iw_mode == IW_MODE_INFRA) {
+ fc |= IEEE80211_FCTL_TODS;
+ /* To DS: Addr1 = BSSID, Addr2 = SA, Addr3 = DA */
+ memcpy(header.addr1, ieee->bssid, ETH_ALEN);
+ memcpy(header.addr2, src, ETH_ALEN);
+ memcpy(header.addr3, dest, ETH_ALEN);
+ } else if (ieee->iw_mode == IW_MODE_ADHOC) {
+ /* not From/To DS: Addr1 = DA, Addr2 = SA, Addr3 = BSSID */
+ memcpy(header.addr1, dest, ETH_ALEN);
+ memcpy(header.addr2, src, ETH_ALEN);
+ memcpy(header.addr3, ieee->bssid, ETH_ALEN);
+ }
+ hdr_len = LIBIPW_3ADDR_LEN;
+
+ if (ieee->is_qos_active && ieee->is_qos_active(dev, skb)) {
+ fc |= IEEE80211_STYPE_QOS_DATA;
+ hdr_len += 2;
+
+ skb->priority = libipw_classify(skb);
+ header.qos_ctl |= cpu_to_le16(skb->priority & LIBIPW_QCTL_TID);
+ }
+ header.frame_ctl = cpu_to_le16(fc);
+
+ /* Advance the SKB to the start of the payload */
+ skb_pull(skb, sizeof(struct ethhdr));
+
+ /* Determine total amount of storage required for TXB packets */
+ bytes = skb->len + SNAP_SIZE + sizeof(u16);
+
+ /* Encrypt msdu first on the whole data packet. */
+ if ((host_encrypt || host_encrypt_msdu) &&
+ crypt && crypt->ops && crypt->ops->encrypt_msdu) {
+ int res = 0;
+ int len = bytes + hdr_len + crypt->ops->extra_msdu_prefix_len +
+ crypt->ops->extra_msdu_postfix_len;
+ struct sk_buff *skb_new = dev_alloc_skb(len);
+
+ if (unlikely(!skb_new))
+ goto failed;
+
+ skb_reserve(skb_new, crypt->ops->extra_msdu_prefix_len);
+ memcpy(skb_put(skb_new, hdr_len), &header, hdr_len);
+ snapped = 1;
+ libipw_copy_snap(skb_put(skb_new, SNAP_SIZE + sizeof(u16)),
+ ether_type);
+ skb_copy_from_linear_data(skb, skb_put(skb_new, skb->len), skb->len);
+ res = crypt->ops->encrypt_msdu(skb_new, hdr_len, crypt->priv);
+ if (res < 0) {
+ LIBIPW_ERROR("msdu encryption failed\n");
+ dev_kfree_skb_any(skb_new);
+ goto failed;
+ }
+ dev_kfree_skb_any(skb);
+ skb = skb_new;
+ bytes += crypt->ops->extra_msdu_prefix_len +
+ crypt->ops->extra_msdu_postfix_len;
+ skb_pull(skb, hdr_len);
+ }
+
+ if (host_encrypt || ieee->host_open_frag) {
+ /* Determine fragmentation size based on destination (multicast
+ * and broadcast are not fragmented) */
+ if (is_multicast_ether_addr(dest) ||
+ is_broadcast_ether_addr(dest))
+ frag_size = MAX_FRAG_THRESHOLD;
+ else
+ frag_size = ieee->fts;
+
+ /* Determine amount of payload per fragment. Regardless of if
+ * this stack is providing the full 802.11 header, one will
+ * eventually be affixed to this fragment -- so we must account
+ * for it when determining the amount of payload space. */
+ bytes_per_frag = frag_size - hdr_len;
+ if (ieee->config &
+ (CFG_LIBIPW_COMPUTE_FCS | CFG_LIBIPW_RESERVE_FCS))
+ bytes_per_frag -= LIBIPW_FCS_LEN;
+
+ /* Each fragment may need to have room for encryption
+ * pre/postfix */
+ if (host_encrypt)
+ bytes_per_frag -= crypt->ops->extra_mpdu_prefix_len +
+ crypt->ops->extra_mpdu_postfix_len;
+
+ /* Number of fragments is the total
+ * bytes_per_frag / payload_per_fragment */
+ nr_frags = bytes / bytes_per_frag;
+ bytes_last_frag = bytes % bytes_per_frag;
+ if (bytes_last_frag)
+ nr_frags++;
+ else
+ bytes_last_frag = bytes_per_frag;
+ } else {
+ nr_frags = 1;
+ bytes_per_frag = bytes_last_frag = bytes;
+ frag_size = bytes + hdr_len;
+ }
+
+ rts_required = (frag_size > ieee->rts
+ && ieee->config & CFG_LIBIPW_RTS);
+ if (rts_required)
+ nr_frags++;
+
+ /* When we allocate the TXB we allocate enough space for the reserve
+ * and full fragment bytes (bytes_per_frag doesn't include prefix,
+ * postfix, header, FCS, etc.) */
+ txb = libipw_alloc_txb(nr_frags, frag_size,
+ ieee->tx_headroom, GFP_ATOMIC);
+ if (unlikely(!txb)) {
+ printk(KERN_WARNING "%s: Could not allocate TXB\n",
+ ieee->dev->name);
+ goto failed;
+ }
+ txb->encrypted = encrypt;
+ if (host_encrypt)
+ txb->payload_size = frag_size * (nr_frags - 1) +
+ bytes_last_frag;
+ else
+ txb->payload_size = bytes;
+
+ if (rts_required) {
+ skb_frag = txb->fragments[0];
+ frag_hdr =
+ (struct libipw_hdr_3addrqos *)skb_put(skb_frag, hdr_len);
+
+ /*
+ * Set header frame_ctl to the RTS.
+ */
+ header.frame_ctl =
+ cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_RTS);
+ memcpy(frag_hdr, &header, hdr_len);
+
+ /*
+ * Restore header frame_ctl to the original data setting.
+ */
+ header.frame_ctl = cpu_to_le16(fc);
+
+ if (ieee->config &
+ (CFG_LIBIPW_COMPUTE_FCS | CFG_LIBIPW_RESERVE_FCS))
+ skb_put(skb_frag, 4);
+
+ txb->rts_included = 1;
+ i = 1;
+ } else
+ i = 0;
+
+ for (; i < nr_frags; i++) {
+ skb_frag = txb->fragments[i];
+
+ if (host_encrypt)
+ skb_reserve(skb_frag,
+ crypt->ops->extra_mpdu_prefix_len);
+
+ frag_hdr =
+ (struct libipw_hdr_3addrqos *)skb_put(skb_frag, hdr_len);
+ memcpy(frag_hdr, &header, hdr_len);
+
+ /* If this is not the last fragment, then add the MOREFRAGS
+ * bit to the frame control */
+ if (i != nr_frags - 1) {
+ frag_hdr->frame_ctl =
+ cpu_to_le16(fc | IEEE80211_FCTL_MOREFRAGS);
+ bytes = bytes_per_frag;
+ } else {
+ /* The last fragment takes the remaining length */
+ bytes = bytes_last_frag;
+ }
+
+ if (i == 0 && !snapped) {
+ libipw_copy_snap(skb_put
+ (skb_frag, SNAP_SIZE + sizeof(u16)),
+ ether_type);
+ bytes -= SNAP_SIZE + sizeof(u16);
+ }
+
+ skb_copy_from_linear_data(skb, skb_put(skb_frag, bytes), bytes);
+
+ /* Advance the SKB... */
+ skb_pull(skb, bytes);
+
+ /* Encryption routine will move the header forward in order
+ * to insert the IV between the header and the payload */
+ if (host_encrypt)
+ libipw_encrypt_fragment(ieee, skb_frag, hdr_len);
+
+ if (ieee->config &
+ (CFG_LIBIPW_COMPUTE_FCS | CFG_LIBIPW_RESERVE_FCS))
+ skb_put(skb_frag, 4);
+ }
+
+ success:
+ spin_unlock_irqrestore(&ieee->lock, flags);
+
+ dev_kfree_skb_any(skb);
+
+ if (txb) {
+ netdev_tx_t ret = (*ieee->hard_start_xmit)(txb, dev, priority);
+ if (ret == NETDEV_TX_OK) {
+ dev->stats.tx_packets++;
+ dev->stats.tx_bytes += txb->payload_size;
+ return NETDEV_TX_OK;
+ }
+
+ libipw_txb_free(txb);
+ }
+
+ return NETDEV_TX_OK;
+
+ failed:
+ spin_unlock_irqrestore(&ieee->lock, flags);
+ netif_stop_queue(dev);
+ dev->stats.tx_errors++;
+ return NETDEV_TX_BUSY;
+}
+EXPORT_SYMBOL(libipw_xmit);
+
+EXPORT_SYMBOL(libipw_txb_free);
Code Review / kvmfornfv.git / blobdiff