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ieee80211_rx.c
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/*
* Original code based Host AP (software wireless LAN access point) driver
* for Intersil Prism2/2.5/3 - hostap.o module, common routines
*
* Copyright (c) 2001-2002, SSH Communications Security Corp and Jouni Malinen
* <j@w1.fi>
* Copyright (c) 2002-2003, Jouni Malinen <j@w1.fi>
* Copyright (c) 2004-2005, Intel Corporation
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation. See README and COPYING for
* more details.
*/
#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 <linux/ctype.h>
#include <net/ieee80211.h>
static void ieee80211_monitor_rx(struct ieee80211_device *ieee,
struct sk_buff *skb,
struct ieee80211_rx_stats *rx_stats)
{
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
u16 fc = le16_to_cpu(hdr->frame_ctl);
skb->dev = ieee->dev;
skb_reset_mac_header(skb);
skb_pull(skb, ieee80211_get_hdrlen(fc));
skb->pkt_type = PACKET_OTHERHOST;
skb->protocol = htons(ETH_P_80211_RAW);
memset(skb->cb, 0, sizeof(skb->cb));
netif_rx(skb);
}
/* Called only as a tasklet (software IRQ) */
static struct ieee80211_frag_entry *ieee80211_frag_cache_find(struct
ieee80211_device
*ieee,
unsigned int seq,
unsigned int frag,
u8 * src,
u8 * dst)
{
struct ieee80211_frag_entry *entry;
int i;
for (i = 0; i < IEEE80211_FRAG_CACHE_LEN; i++) {
entry = &ieee->frag_cache[i];
if (entry->skb != NULL &&
time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
IEEE80211_DEBUG_FRAG("expiring fragment cache entry "
"seq=%u last_frag=%u\n",
entry->seq, entry->last_frag);
dev_kfree_skb_any(entry->skb);
entry->skb = NULL;
}
if (entry->skb != NULL && entry->seq == seq &&
(entry->last_frag + 1 == frag || frag == -1) &&
!compare_ether_addr(entry->src_addr, src) &&
!compare_ether_addr(entry->dst_addr, dst))
return entry;
}
return NULL;
}
/* Called only as a tasklet (software IRQ) */
static struct sk_buff *ieee80211_frag_cache_get(struct ieee80211_device *ieee,
struct ieee80211_hdr_4addr *hdr)
{
struct sk_buff *skb = NULL;
u16 sc;
unsigned int frag, seq;
struct ieee80211_frag_entry *entry;
sc = le16_to_cpu(hdr->seq_ctl);
frag = WLAN_GET_SEQ_FRAG(sc);
seq = WLAN_GET_SEQ_SEQ(sc);
if (frag == 0) {
/* Reserve enough space to fit maximum frame length */
skb = dev_alloc_skb(ieee->dev->mtu +
sizeof(struct ieee80211_hdr_4addr) +
8 /* LLC */ +
2 /* alignment */ +
8 /* WEP */ + ETH_ALEN /* WDS */ );
if (skb == NULL)
return NULL;
entry = &ieee->frag_cache[ieee->frag_next_idx];
ieee->frag_next_idx++;
if (ieee->frag_next_idx >= IEEE80211_FRAG_CACHE_LEN)
ieee->frag_next_idx = 0;
if (entry->skb != NULL)
dev_kfree_skb_any(entry->skb);
entry->first_frag_time = jiffies;
entry->seq = seq;
entry->last_frag = frag;
entry->skb = skb;
memcpy(entry->src_addr, hdr->addr2, ETH_ALEN);
memcpy(entry->dst_addr, hdr->addr1, ETH_ALEN);
} else {
/* received a fragment of a frame for which the head fragment
* should have already been received */
entry = ieee80211_frag_cache_find(ieee, seq, frag, hdr->addr2,
hdr->addr1);
if (entry != NULL) {
entry->last_frag = frag;
skb = entry->skb;
}
}
return skb;
}
/* Called only as a tasklet (software IRQ) */
static int ieee80211_frag_cache_invalidate(struct ieee80211_device *ieee,
struct ieee80211_hdr_4addr *hdr)
{
u16 sc;
unsigned int seq;
struct ieee80211_frag_entry *entry;
sc = le16_to_cpu(hdr->seq_ctl);
seq = WLAN_GET_SEQ_SEQ(sc);
entry = ieee80211_frag_cache_find(ieee, seq, -1, hdr->addr2,
hdr->addr1);
if (entry == NULL) {
IEEE80211_DEBUG_FRAG("could not invalidate fragment cache "
"entry (seq=%u)\n", seq);
return -1;
}
entry->skb = NULL;
return 0;
}
#ifdef NOT_YET
/* ieee80211_rx_frame_mgtmt
*
* Responsible for handling management control frames
*
* Called by ieee80211_rx */
static int
ieee80211_rx_frame_mgmt(struct ieee80211_device *ieee, struct sk_buff *skb,
struct ieee80211_rx_stats *rx_stats, u16 type,
u16 stype)
{
if (ieee->iw_mode == IW_MODE_MASTER) {
printk(KERN_DEBUG "%s: Master mode not yet suppported.\n",
ieee->dev->name);
return 0;
/*
hostap_update_sta_ps(ieee, (struct hostap_ieee80211_hdr_4addr *)
skb->data);*/
}
if (ieee->hostapd && type == WLAN_FC_TYPE_MGMT) {
if (stype == WLAN_FC_STYPE_BEACON &&
ieee->iw_mode == IW_MODE_MASTER) {
struct sk_buff *skb2;
/* Process beacon frames also in kernel driver to
* update STA(AP) table statistics */
skb2 = skb_clone(skb, GFP_ATOMIC);
if (skb2)
hostap_rx(skb2->dev, skb2, rx_stats);
}
/* send management frames to the user space daemon for
* processing */
ieee->apdevstats.rx_packets++;
ieee->apdevstats.rx_bytes += skb->len;
prism2_rx_80211(ieee->apdev, skb, rx_stats, PRISM2_RX_MGMT);
return 0;
}
if (ieee->iw_mode == IW_MODE_MASTER) {
if (type != WLAN_FC_TYPE_MGMT && type != WLAN_FC_TYPE_CTRL) {
printk(KERN_DEBUG "%s: unknown management frame "
"(type=0x%02x, stype=0x%02x) dropped\n",
skb->dev->name, type, stype);
return -1;
}
hostap_rx(skb->dev, skb, rx_stats);
return 0;
}
printk(KERN_DEBUG "%s: hostap_rx_frame_mgmt: management frame "
"received in non-Host AP mode\n", skb->dev->name);
return -1;
}
#endif
/* See IEEE 802.1H for LLC/SNAP encapsulation/decapsulation */
/* Ethernet-II snap header (RFC1042 for most EtherTypes) */
static unsigned char rfc1042_header[] = { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 };
/* Bridge-Tunnel header (for EtherTypes ETH_P_AARP and ETH_P_IPX) */
static unsigned char bridge_tunnel_header[] =
{ 0xaa, 0xaa, 0x03, 0x00, 0x00, 0xf8 };
/* No encapsulation header if EtherType < 0x600 (=length) */
/* Called by ieee80211_rx_frame_decrypt */
static int ieee80211_is_eapol_frame(struct ieee80211_device *ieee,
struct sk_buff *skb)
{
struct net_device *dev = ieee->dev;
u16 fc, ethertype;
struct ieee80211_hdr_3addr *hdr;
u8 *pos;
if (skb->len < 24)
return 0;
hdr = (struct ieee80211_hdr_3addr *)skb->data;
fc = le16_to_cpu(hdr->frame_ctl);
/* check that the frame is unicast frame to us */
if ((fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) ==
IEEE80211_FCTL_TODS &&
!compare_ether_addr(hdr->addr1, dev->dev_addr) &&
!compare_ether_addr(hdr->addr3, dev->dev_addr)) {
/* ToDS frame with own addr BSSID and DA */
} else if ((fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) ==
IEEE80211_FCTL_FROMDS &&
!compare_ether_addr(hdr->addr1, dev->dev_addr)) {
/* FromDS frame with own addr as DA */
} else
return 0;
if (skb->len < 24 + 8)
return 0;
/* check for port access entity Ethernet type */
pos = skb->data + 24;
ethertype = (pos[6] << 8) | pos[7];
if (ethertype == ETH_P_PAE)
return 1;
return 0;
}
/* Called only as a tasklet (software IRQ), by ieee80211_rx */
static int
ieee80211_rx_frame_decrypt(struct ieee80211_device *ieee, struct sk_buff *skb,
struct ieee80211_crypt_data *crypt)
{
struct ieee80211_hdr_3addr *hdr;
int res, hdrlen;
if (crypt == NULL || crypt->ops->decrypt_mpdu == NULL)
return 0;
hdr = (struct ieee80211_hdr_3addr *)skb->data;
hdrlen = ieee80211_get_hdrlen(le16_to_cpu(hdr->frame_ctl));
atomic_inc(&crypt->refcnt);
res = crypt->ops->decrypt_mpdu(skb, hdrlen, crypt->priv);
atomic_dec(&crypt->refcnt);
if (res < 0) {
IEEE80211_DEBUG_DROP("decryption failed (SA=%pM) res=%d\n",
hdr->addr2, res);
if (res == -2)
IEEE80211_DEBUG_DROP("Decryption failed ICV "
"mismatch (key %d)\n",
skb->data[hdrlen + 3] >> 6);
ieee->ieee_stats.rx_discards_undecryptable++;
return -1;
}
return res;
}
/* Called only as a tasklet (software IRQ), by ieee80211_rx */
static int
ieee80211_rx_frame_decrypt_msdu(struct ieee80211_device *ieee,
struct sk_buff *skb, int keyidx,
struct ieee80211_crypt_data *crypt)
{
struct ieee80211_hdr_3addr *hdr;
int res, hdrlen;
if (crypt == NULL || crypt->ops->decrypt_msdu == NULL)
return 0;
hdr = (struct ieee80211_hdr_3addr *)skb->data;
hdrlen = ieee80211_get_hdrlen(le16_to_cpu(hdr->frame_ctl));
atomic_inc(&crypt->refcnt);
res = crypt->ops->decrypt_msdu(skb, keyidx, hdrlen, crypt->priv);
atomic_dec(&crypt->refcnt);
if (res < 0) {
printk(KERN_DEBUG "%s: MSDU decryption/MIC verification failed"
" (SA=%pM keyidx=%d)\n", ieee->dev->name, hdr->addr2,
keyidx);
return -1;
}
return 0;
}
/* All received frames are sent to this function. @skb contains the frame in
* IEEE 802.11 format, i.e., in the format it was sent over air.
* This function is called only as a tasklet (software IRQ). */
int ieee80211_rx(struct ieee80211_device *ieee, struct sk_buff *skb,
struct ieee80211_rx_stats *rx_stats)
{
struct net_device *dev = ieee->dev;
struct ieee80211_hdr_4addr *hdr;
size_t hdrlen;
u16 fc, type, stype, sc;
struct net_device_stats *stats;
unsigned int frag;
u8 *payload;
u16 ethertype;
#ifdef NOT_YET
struct net_device *wds = NULL;
struct sk_buff *skb2 = NULL;
struct net_device *wds = NULL;
int frame_authorized = 0;
int from_assoc_ap = 0;
void *sta = NULL;
#endif
u8 dst[ETH_ALEN];
u8 src[ETH_ALEN];
struct ieee80211_crypt_data *crypt = NULL;
int keyidx = 0;
int can_be_decrypted = 0;
hdr = (struct ieee80211_hdr_4addr *)skb->data;
stats = &ieee->stats;
if (skb->len < 10) {
printk(KERN_INFO "%s: SKB length < 10\n", dev->name);
goto rx_dropped;
}
fc = le16_to_cpu(hdr->frame_ctl);
type = WLAN_FC_GET_TYPE(fc);
stype = WLAN_FC_GET_STYPE(fc);
sc = le16_to_cpu(hdr->seq_ctl);
frag = WLAN_GET_SEQ_FRAG(sc);
hdrlen = ieee80211_get_hdrlen(fc);
if (skb->len < hdrlen) {
printk(KERN_INFO "%s: invalid SKB length %d\n",
dev->name, skb->len);
goto rx_dropped;
}
/* Put this code here so that we avoid duplicating it in all
* Rx paths. - Jean II */
#ifdef CONFIG_WIRELESS_EXT
#ifdef IW_WIRELESS_SPY /* defined in iw_handler.h */
/* If spy monitoring on */
if (ieee->spy_data.spy_number > 0) {
struct iw_quality wstats;
wstats.updated = 0;
if (rx_stats->mask & IEEE80211_STATMASK_RSSI) {
wstats.level = rx_stats->signal;
wstats.updated |= IW_QUAL_LEVEL_UPDATED;
} else
wstats.updated |= IW_QUAL_LEVEL_INVALID;
if (rx_stats->mask & IEEE80211_STATMASK_NOISE) {
wstats.noise = rx_stats->noise;
wstats.updated |= IW_QUAL_NOISE_UPDATED;
} else
wstats.updated |= IW_QUAL_NOISE_INVALID;
if (rx_stats->mask & IEEE80211_STATMASK_SIGNAL) {
wstats.qual = rx_stats->signal;
wstats.updated |= IW_QUAL_QUAL_UPDATED;
} else
wstats.updated |= IW_QUAL_QUAL_INVALID;
/* Update spy records */
wireless_spy_update(ieee->dev, hdr->addr2, &wstats);
}
#endif /* IW_WIRELESS_SPY */
#endif /* CONFIG_WIRELESS_EXT */
#ifdef NOT_YET
hostap_update_rx_stats(local->ap, hdr, rx_stats);
#endif
if (ieee->iw_mode == IW_MODE_MONITOR) {
stats->rx_packets++;
stats->rx_bytes += skb->len;
ieee80211_monitor_rx(ieee, skb, rx_stats);
return 1;
}
can_be_decrypted = (is_multicast_ether_addr(hdr->addr1) ||
is_broadcast_ether_addr(hdr->addr2)) ?
ieee->host_mc_decrypt : ieee->host_decrypt;
if (can_be_decrypted) {
if (skb->len >= hdrlen + 3) {
/* Top two-bits of byte 3 are the key index */
keyidx = skb->data[hdrlen + 3] >> 6;
}
/* ieee->crypt[] is WEP_KEY (4) in length. Given that keyidx
* is only allowed 2-bits of storage, no value of keyidx can
* be provided via above code that would result in keyidx
* being out of range */
crypt = ieee->crypt[keyidx];
#ifdef NOT_YET
sta = NULL;
/* Use station specific key to override default keys if the
* receiver address is a unicast address ("individual RA"). If
* bcrx_sta_key parameter is set, station specific key is used
* even with broad/multicast targets (this is against IEEE
* 802.11, but makes it easier to use different keys with
* stations that do not support WEP key mapping). */
if (!(hdr->addr1[0] & 0x01) || local->bcrx_sta_key)
(void)hostap_handle_sta_crypto(local, hdr, &crypt,
&sta);
#endif
/* allow NULL decrypt to indicate an station specific override
* for default encryption */
if (crypt && (crypt->ops == NULL ||
crypt->ops->decrypt_mpdu == NULL))
crypt = NULL;
if (!crypt && (fc & IEEE80211_FCTL_PROTECTED)) {
/* This seems to be triggered by some (multicast?)
* frames from other than current BSS, so just drop the
* frames silently instead of filling system log with
* these reports. */
IEEE80211_DEBUG_DROP("Decryption failed (not set)"
" (SA=%pM)\n", hdr->addr2);
ieee->ieee_stats.rx_discards_undecryptable++;
goto rx_dropped;
}
}
#ifdef NOT_YET
if (type != WLAN_FC_TYPE_DATA) {
if (type == WLAN_FC_TYPE_MGMT && stype == WLAN_FC_STYPE_AUTH &&
fc & IEEE80211_FCTL_PROTECTED && ieee->host_decrypt &&
(keyidx = hostap_rx_frame_decrypt(ieee, skb, crypt)) < 0) {
printk(KERN_DEBUG "%s: failed to decrypt mgmt::auth "
"from %pM\n", dev->name, hdr->addr2);
/* TODO: could inform hostapd about this so that it
* could send auth failure report */
goto rx_dropped;
}
if (ieee80211_rx_frame_mgmt(ieee, skb, rx_stats, type, stype))
goto rx_dropped;
else
goto rx_exit;
}
#endif
/* drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.29) */
if (sc == ieee->prev_seq_ctl)
goto rx_dropped;
else
ieee->prev_seq_ctl = sc;
/* Data frame - extract src/dst addresses */
if (skb->len < IEEE80211_3ADDR_LEN)
goto rx_dropped;
switch (fc & (IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS)) {
case IEEE80211_FCTL_FROMDS:
memcpy(dst, hdr->addr1, ETH_ALEN);
memcpy(src, hdr->addr3, ETH_ALEN);
break;
case IEEE80211_FCTL_TODS:
memcpy(dst, hdr->addr3, ETH_ALEN);
memcpy(src, hdr->addr2, ETH_ALEN);
break;
case IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS:
if (skb->len < IEEE80211_4ADDR_LEN)
goto rx_dropped;
memcpy(dst, hdr->addr3, ETH_ALEN);
memcpy(src, hdr->addr4, ETH_ALEN);
break;
case 0:
memcpy(dst, hdr->addr1, ETH_ALEN);
memcpy(src, hdr->addr2, ETH_ALEN);
break;
}
#ifdef NOT_YET
if (hostap_rx_frame_wds(ieee, hdr, fc, &wds))
goto rx_dropped;
if (wds) {
skb->dev = dev = wds;
stats = hostap_get_stats(dev);
}
if (ieee->iw_mode == IW_MODE_MASTER && !wds &&
(fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) ==
IEEE80211_FCTL_FROMDS && ieee->stadev
&& !compare_ether_addr(hdr->addr2, ieee->assoc_ap_addr)) {
/* Frame from BSSID of the AP for which we are a client */
skb->dev = dev = ieee->stadev;
stats = hostap_get_stats(dev);
from_assoc_ap = 1;
}
#endif
dev->last_rx = jiffies;
#ifdef NOT_YET
if ((ieee->iw_mode == IW_MODE_MASTER ||
ieee->iw_mode == IW_MODE_REPEAT) && !from_assoc_ap) {
switch (hostap_handle_sta_rx(ieee, dev, skb, rx_stats,
wds != NULL)) {
case AP_RX_CONTINUE_NOT_AUTHORIZED:
frame_authorized = 0;
break;
case AP_RX_CONTINUE:
frame_authorized = 1;
break;
case AP_RX_DROP:
goto rx_dropped;
case AP_RX_EXIT:
goto rx_exit;
}
}
#endif
/* Nullfunc frames may have PS-bit set, so they must be passed to
* hostap_handle_sta_rx() before being dropped here. */
stype &= ~IEEE80211_STYPE_QOS_DATA;
if (stype != IEEE80211_STYPE_DATA &&
stype != IEEE80211_STYPE_DATA_CFACK &&
stype != IEEE80211_STYPE_DATA_CFPOLL &&
stype != IEEE80211_STYPE_DATA_CFACKPOLL) {
if (stype != IEEE80211_STYPE_NULLFUNC)
IEEE80211_DEBUG_DROP("RX: dropped data frame "
"with no data (type=0x%02x, "
"subtype=0x%02x, len=%d)\n",
type, stype, skb->len);
goto rx_dropped;
}
/* skb: hdr + (possibly fragmented, possibly encrypted) payload */
if ((fc & IEEE80211_FCTL_PROTECTED) && can_be_decrypted &&
(keyidx = ieee80211_rx_frame_decrypt(ieee, skb, crypt)) < 0)
goto rx_dropped;
hdr = (struct ieee80211_hdr_4addr *)skb->data;
/* skb: hdr + (possibly fragmented) plaintext payload */
// PR: FIXME: hostap has additional conditions in the "if" below:
// ieee->host_decrypt && (fc & IEEE80211_FCTL_PROTECTED) &&
if ((frag != 0) || (fc & IEEE80211_FCTL_MOREFRAGS)) {
int flen;
struct sk_buff *frag_skb = ieee80211_frag_cache_get(ieee, hdr);
IEEE80211_DEBUG_FRAG("Rx Fragment received (%u)\n", frag);
if (!frag_skb) {
IEEE80211_DEBUG(IEEE80211_DL_RX | IEEE80211_DL_FRAG,
"Rx cannot get skb from fragment "
"cache (morefrag=%d seq=%u frag=%u)\n",
(fc & IEEE80211_FCTL_MOREFRAGS) != 0,
WLAN_GET_SEQ_SEQ(sc), frag);
goto rx_dropped;
}
flen = skb->len;
if (frag != 0)
flen -= hdrlen;
if (frag_skb->tail + flen > frag_skb->end) {
printk(KERN_WARNING "%s: host decrypted and "
"reassembled frame did not fit skb\n",
dev->name);
ieee80211_frag_cache_invalidate(ieee, hdr);
goto rx_dropped;
}
if (frag == 0) {
/* copy first fragment (including full headers) into
* beginning of the fragment cache skb */
skb_copy_from_linear_data(skb, skb_put(frag_skb, flen), flen);
} else {
/* append frame payload to the end of the fragment
* cache skb */
skb_copy_from_linear_data_offset(skb, hdrlen,
skb_put(frag_skb, flen), flen);
}
dev_kfree_skb_any(skb);
skb = NULL;
if (fc & IEEE80211_FCTL_MOREFRAGS) {
/* more fragments expected - leave the skb in fragment
* cache for now; it will be delivered to upper layers
* after all fragments have been received */
goto rx_exit;
}
/* this was the last fragment and the frame will be
* delivered, so remove skb from fragment cache */
skb = frag_skb;
hdr = (struct ieee80211_hdr_4addr *)skb->data;
ieee80211_frag_cache_invalidate(ieee, hdr);
}
/* skb: hdr + (possible reassembled) full MSDU payload; possibly still
* encrypted/authenticated */
if ((fc & IEEE80211_FCTL_PROTECTED) && can_be_decrypted &&
ieee80211_rx_frame_decrypt_msdu(ieee, skb, keyidx, crypt))
goto rx_dropped;
hdr = (struct ieee80211_hdr_4addr *)skb->data;
if (crypt && !(fc & IEEE80211_FCTL_PROTECTED) && !ieee->open_wep) {
if ( /*ieee->ieee802_1x && */
ieee80211_is_eapol_frame(ieee, skb)) {
/* pass unencrypted EAPOL frames even if encryption is
* configured */
} else {
IEEE80211_DEBUG_DROP("encryption configured, but RX "
"frame not encrypted (SA=%pM)\n",
hdr->addr2);
goto rx_dropped;
}
}
if (crypt && !(fc & IEEE80211_FCTL_PROTECTED) && !ieee->open_wep &&
!ieee80211_is_eapol_frame(ieee, skb)) {
IEEE80211_DEBUG_DROP("dropped unencrypted RX data "
"frame from %pM (drop_unencrypted=1)\n",
hdr->addr2);
goto rx_dropped;
}
/* If the frame was decrypted in hardware, we may need to strip off
* any security data (IV, ICV, etc) that was left behind */
if (!can_be_decrypted && (fc & IEEE80211_FCTL_PROTECTED) &&
ieee->host_strip_iv_icv) {
int trimlen = 0;
/* Top two-bits of byte 3 are the key index */
if (skb->len >= hdrlen + 3)
keyidx = skb->data[hdrlen + 3] >> 6;
/* To strip off any security data which appears before the
* payload, we simply increase hdrlen (as the header gets
* chopped off immediately below). For the security data which
* appears after the payload, we use skb_trim. */
switch (ieee->sec.encode_alg[keyidx]) {
case SEC_ALG_WEP:
/* 4 byte IV */
hdrlen += 4;
/* 4 byte ICV */
trimlen = 4;
break;
case SEC_ALG_TKIP:
/* 4 byte IV, 4 byte ExtIV */
hdrlen += 8;
/* 8 byte MIC, 4 byte ICV */
trimlen = 12;
break;
case SEC_ALG_CCMP:
/* 8 byte CCMP header */
hdrlen += 8;
/* 8 byte MIC */
trimlen = 8;
break;
}
if (skb->len < trimlen)
goto rx_dropped;
__skb_trim(skb, skb->len - trimlen);
if (skb->len < hdrlen)
goto rx_dropped;
}
/* skb: hdr + (possible reassembled) full plaintext payload */
payload = skb->data + hdrlen;
ethertype = (payload[6] << 8) | payload[7];
#ifdef NOT_YET
/* If IEEE 802.1X is used, check whether the port is authorized to send
* the received frame. */
if (ieee->ieee802_1x && ieee->iw_mode == IW_MODE_MASTER) {
if (ethertype == ETH_P_PAE) {
printk(KERN_DEBUG "%s: RX: IEEE 802.1X frame\n",
dev->name);
if (ieee->hostapd && ieee->apdev) {
/* Send IEEE 802.1X frames to the user
* space daemon for processing */
prism2_rx_80211(ieee->apdev, skb, rx_stats,
PRISM2_RX_MGMT);
ieee->apdevstats.rx_packets++;
ieee->apdevstats.rx_bytes += skb->len;
goto rx_exit;
}
} else if (!frame_authorized) {
printk(KERN_DEBUG "%s: dropped frame from "
"unauthorized port (IEEE 802.1X): "
"ethertype=0x%04x\n", dev->name, ethertype);
goto rx_dropped;
}
}
#endif
/* convert hdr + possible LLC headers into Ethernet header */
if (skb->len - hdrlen >= 8 &&
((memcmp(payload, rfc1042_header, SNAP_SIZE) == 0 &&
ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
memcmp(payload, bridge_tunnel_header, SNAP_SIZE) == 0)) {
/* remove RFC1042 or Bridge-Tunnel encapsulation and
* replace EtherType */
skb_pull(skb, hdrlen + SNAP_SIZE);
memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
} else {
__be16 len;
/* Leave Ethernet header part of hdr and full payload */
skb_pull(skb, hdrlen);
len = htons(skb->len);
memcpy(skb_push(skb, 2), &len, 2);
memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
}
#ifdef NOT_YET
if (wds && ((fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) ==
IEEE80211_FCTL_TODS) && skb->len >= ETH_HLEN + ETH_ALEN) {
/* Non-standard frame: get addr4 from its bogus location after
* the payload */
skb_copy_to_linear_data_offset(skb, ETH_ALEN,
skb->data + skb->len - ETH_ALEN,
ETH_ALEN);
skb_trim(skb, skb->len - ETH_ALEN);
}
#endif
stats->rx_packets++;
stats->rx_bytes += skb->len;
#ifdef NOT_YET
if (ieee->iw_mode == IW_MODE_MASTER && !wds && ieee->ap->bridge_packets) {
if (dst[0] & 0x01) {
/* copy multicast frame both to the higher layers and
* to the wireless media */
ieee->ap->bridged_multicast++;
skb2 = skb_clone(skb, GFP_ATOMIC);
if (skb2 == NULL)
printk(KERN_DEBUG "%s: skb_clone failed for "
"multicast frame\n", dev->name);
} else if (hostap_is_sta_assoc(ieee->ap, dst)) {
/* send frame directly to the associated STA using
* wireless media and not passing to higher layers */
ieee->ap->bridged_unicast++;
skb2 = skb;
skb = NULL;
}
}
if (skb2 != NULL) {
/* send to wireless media */
skb2->dev = dev;
skb2->protocol = htons(ETH_P_802_3);
skb_reset_mac_header(skb2);
skb_reset_network_header(skb2);
/* skb2->network_header += ETH_HLEN; */
dev_queue_xmit(skb2);
}
#endif
if (skb) {
skb->protocol = eth_type_trans(skb, dev);
memset(skb->cb, 0, sizeof(skb->cb));
skb->ip_summed = CHECKSUM_NONE; /* 802.11 crc not sufficient */
if (netif_rx(skb) == NET_RX_DROP) {
/* netif_rx always succeeds, but it might drop
* the packet. If it drops the packet, we log that
* in our stats. */
IEEE80211_DEBUG_DROP
("RX: netif_rx dropped the packet\n");
stats->rx_dropped++;
}
}
rx_exit:
#ifdef NOT_YET
if (sta)
hostap_handle_sta_release(sta);
#endif
return 1;
rx_dropped:
stats->rx_dropped++;
/* Returning 0 indicates to caller that we have not handled the SKB--
* so it is still allocated and can be used again by underlying
* hardware as a DMA target */
return 0;
}
/* Filter out unrelated packets, call ieee80211_rx[_mgt]
* This function takes over the skb, it should not be used again after calling
* this function. */
void ieee80211_rx_any(struct ieee80211_device *ieee,
struct sk_buff *skb, struct ieee80211_rx_stats *stats)
{
struct ieee80211_hdr_4addr *hdr;
int is_packet_for_us;
u16 fc;
if (ieee->iw_mode == IW_MODE_MONITOR) {
if (!ieee80211_rx(ieee, skb, stats))
dev_kfree_skb_irq(skb);
return;
}
if (skb->len < sizeof(struct ieee80211_hdr))
goto drop_free;
hdr = (struct ieee80211_hdr_4addr *)skb->data;
fc = le16_to_cpu(hdr->frame_ctl);
if ((fc & IEEE80211_FCTL_VERS) != 0)
goto drop_free;
switch (fc & IEEE80211_FCTL_FTYPE) {
case IEEE80211_FTYPE_MGMT:
if (skb->len < sizeof(struct ieee80211_hdr_3addr))
goto drop_free;
ieee80211_rx_mgt(ieee, hdr, stats);
dev_kfree_skb_irq(skb);
return;
case IEEE80211_FTYPE_DATA:
break;
case IEEE80211_FTYPE_CTL:
return;
default:
return;
}
is_packet_for_us = 0;
switch (ieee->iw_mode) {
case IW_MODE_ADHOC:
/* our BSS and not from/to DS */
if (memcmp(hdr->addr3, ieee->bssid, ETH_ALEN) == 0)
if ((fc & (IEEE80211_FCTL_TODS+IEEE80211_FCTL_FROMDS)) == 0) {
/* promisc: get all */
if (ieee->dev->flags & IFF_PROMISC)
is_packet_for_us = 1;
/* to us */
else if (memcmp(hdr->addr1, ieee->dev->dev_addr, ETH_ALEN) == 0)
is_packet_for_us = 1;
/* mcast */
else if (is_multicast_ether_addr(hdr->addr1))
is_packet_for_us = 1;
}
break;
case IW_MODE_INFRA:
/* our BSS (== from our AP) and from DS */
if (memcmp(hdr->addr2, ieee->bssid, ETH_ALEN) == 0)
if ((fc & (IEEE80211_FCTL_TODS+IEEE80211_FCTL_FROMDS)) == IEEE80211_FCTL_FROMDS) {
/* promisc: get all */
if (ieee->dev->flags & IFF_PROMISC)
is_packet_for_us = 1;
/* to us */
else if (memcmp(hdr->addr1, ieee->dev->dev_addr, ETH_ALEN) == 0)
is_packet_for_us = 1;
/* mcast */
else if (is_multicast_ether_addr(hdr->addr1)) {
/* not our own packet bcasted from AP */
if (memcmp(hdr->addr3, ieee->dev->dev_addr, ETH_ALEN))
is_packet_for_us = 1;
}
}
break;
default:
/* ? */
break;
}
if (is_packet_for_us)
if (!ieee80211_rx(ieee, skb, stats))
dev_kfree_skb_irq(skb);
return;
drop_free:
dev_kfree_skb_irq(skb);
ieee->stats.rx_dropped++;
return;
}
#define MGMT_FRAME_FIXED_PART_LENGTH 0x24
static u8 qos_oui[QOS_OUI_LEN] = { 0x00, 0x50, 0xF2 };
/*
* Make ther structure we read from the beacon packet has
* the right values
*/
static int ieee80211_verify_qos_info(struct ieee80211_qos_information_element
*info_element, int sub_type)
{
if (info_element->qui_subtype != sub_type)
return -1;
if (memcmp(info_element->qui, qos_oui, QOS_OUI_LEN))
return -1;
if (info_element->qui_type != QOS_OUI_TYPE)
return -1;
if (info_element->version != QOS_VERSION_1)
return -1;
return 0;
}
/*
* Parse a QoS parameter element
*/
static int ieee80211_read_qos_param_element(struct ieee80211_qos_parameter_info
*element_param, struct ieee80211_info_element
*info_element)
{
int ret = 0;
u16 size = sizeof(struct ieee80211_qos_parameter_info) - 2;
if ((info_element == NULL) || (element_param == NULL))
return -1;
if (info_element->id == QOS_ELEMENT_ID && info_element->len == size) {
memcpy(element_param->info_element.qui, info_element->data,
info_element->len);
element_param->info_element.elementID = info_element->id;
element_param->info_element.length = info_element->len;
} else
ret = -1;
if (ret == 0)
ret = ieee80211_verify_qos_info(&element_param->info_element,
QOS_OUI_PARAM_SUB_TYPE);
return ret;
}
/*
* Parse a QoS information element
*/
static int ieee80211_read_qos_info_element(struct
ieee80211_qos_information_element
*element_info, struct ieee80211_info_element
*info_element)
{
int ret = 0;
u16 size = sizeof(struct ieee80211_qos_information_element) - 2;
if (element_info == NULL)
return -1;
if (info_element == NULL)
return -1;
if ((info_element->id == QOS_ELEMENT_ID) && (info_element->len == size)) {
memcpy(element_info->qui, info_element->data,
info_element->len);
element_info->elementID = info_element->id;
element_info->length = info_element->len;
} else
ret = -1;
if (ret == 0)