linux/net/ieee80211/ieee80211_rx.c

1194 lines
34 KiB
C

/*
* 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
* <jkmaline@cc.hut.fi>
* Copyright (c) 2002-2003, Jouni Malinen <jkmaline@cc.hut.fi>
* Copyright (c) 2004, 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/config.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/version.h>
#include <linux/wireless.h>
#include <linux/etherdevice.h>
#include <asm/uaccess.h>
#include <linux/ctype.h>
#include <net/ieee80211.h>
static inline 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->mac.raw = skb->data;
skb_pull(skb, ieee80211_get_hdrlen(fc));
skb->pkt_type = PACKET_OTHERHOST;
skb->protocol = __constant_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) &&
memcmp(entry->src_addr, src, ETH_ALEN) == 0 &&
memcmp(entry->dst_addr, dst, ETH_ALEN) == 0)
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 *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) +
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 *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 inline 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 *)
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 *hdr;
u8 *pos;
if (skb->len < 24)
return 0;
hdr = (struct ieee80211_hdr *)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 &&
memcmp(hdr->addr1, dev->dev_addr, ETH_ALEN) == 0 &&
memcmp(hdr->addr3, dev->dev_addr, ETH_ALEN) == 0) {
/* ToDS frame with own addr BSSID and DA */
} else if ((fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) ==
IEEE80211_FCTL_FROMDS &&
memcmp(hdr->addr1, dev->dev_addr, ETH_ALEN) == 0) {
/* 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 inline int
ieee80211_rx_frame_decrypt(struct ieee80211_device *ieee, struct sk_buff *skb,
struct ieee80211_crypt_data *crypt)
{
struct ieee80211_hdr *hdr;
int res, hdrlen;
if (crypt == NULL || crypt->ops->decrypt_mpdu == NULL)
return 0;
hdr = (struct ieee80211_hdr *)skb->data;
hdrlen = ieee80211_get_hdrlen(le16_to_cpu(hdr->frame_ctl));
#ifdef CONFIG_IEEE80211_CRYPT_TKIP
if (ieee->tkip_countermeasures && strcmp(crypt->ops->name, "TKIP") == 0) {
if (net_ratelimit()) {
printk(KERN_DEBUG "%s: TKIP countermeasures: dropped "
"received packet from " MAC_FMT "\n",
ieee->dev->name, MAC_ARG(hdr->addr2));
}
return -1;
}
#endif
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=" MAC_FMT
") res=%d\n", MAC_ARG(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 inline int
ieee80211_rx_frame_decrypt_msdu(struct ieee80211_device *ieee,
struct sk_buff *skb, int keyidx,
struct ieee80211_crypt_data *crypt)
{
struct ieee80211_hdr *hdr;
int res, hdrlen;
if (crypt == NULL || crypt->ops->decrypt_msdu == NULL)
return 0;
hdr = (struct ieee80211_hdr *)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=" MAC_FMT " keyidx=%d)\n",
ieee->dev->name, MAC_ARG(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 *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;
hdr = (struct ieee80211_hdr *)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);
#ifdef NOT_YET
#if WIRELESS_EXT > 15
/* Put this code here so that we avoid duplicating it in all
* Rx paths. - Jean II */
#ifdef IW_WIRELESS_SPY /* defined in iw_handler.h */
/* If spy monitoring on */
if (iface->spy_data.spy_number > 0) {
struct iw_quality wstats;
wstats.level = rx_stats->signal;
wstats.noise = rx_stats->noise;
wstats.updated = 6; /* No qual value */
/* Update spy records */
wireless_spy_update(dev, hdr->addr2, &wstats);
}
#endif /* IW_WIRELESS_SPY */
#endif /* WIRELESS_EXT > 15 */
hostap_update_rx_stats(local->ap, hdr, rx_stats);
#endif
#if WIRELESS_EXT > 15
if (ieee->iw_mode == IW_MODE_MONITOR) {
ieee80211_monitor_rx(ieee, skb, rx_stats);
stats->rx_packets++;
stats->rx_bytes += skb->len;
return 1;
}
#endif
if (ieee->host_decrypt) {
int idx = 0;
if (skb->len >= hdrlen + 3)
idx = skb->data[hdrlen + 3] >> 6;
crypt = ieee->crypt[idx];
#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=" MAC_FMT ")\n",
MAC_ARG(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 " MAC_FMT "\n", dev->name,
MAC_ARG(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
/* 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
&& memcmp(hdr->addr2, ieee->assoc_ap_addr, ETH_ALEN) == 0) {
/* 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. */
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 (ieee->host_decrypt && (fc & IEEE80211_FCTL_PROTECTED) &&
(keyidx = ieee80211_rx_frame_decrypt(ieee, skb, crypt)) < 0)
goto rx_dropped;
hdr = (struct ieee80211_hdr *)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 */
memcpy(skb_put(frag_skb, flen), skb->data, flen);
} else {
/* append frame payload to the end of the fragment
* cache skb */
memcpy(skb_put(frag_skb, flen), skb->data + hdrlen,
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 *)skb->data;
ieee80211_frag_cache_invalidate(ieee, hdr);
}
/* skb: hdr + (possible reassembled) full MSDU payload; possibly still
* encrypted/authenticated */
if (ieee->host_decrypt && (fc & IEEE80211_FCTL_PROTECTED) &&
ieee80211_rx_frame_decrypt_msdu(ieee, skb, keyidx, crypt))
goto rx_dropped;
hdr = (struct ieee80211_hdr *)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=" MAC_FMT
")\n", MAC_ARG(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 " MAC_FMT
" (drop_unencrypted=1)\n",
MAC_ARG(hdr->addr2));
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 {
u16 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 */
memcpy(skb->data + 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->protocol = __constant_htons(ETH_P_802_3);
skb2->mac.raw = skb2->nh.raw = skb2->data;
/* skb2->nh.raw = skb2->data + ETH_HLEN; */
skb2->dev = dev;
dev_queue_xmit(skb2);
}
#endif
if (skb) {
skb->protocol = eth_type_trans(skb, dev);
memset(skb->cb, 0, sizeof(skb->cb));
skb->dev = dev;
skb->ip_summed = CHECKSUM_NONE; /* 802.11 crc not sufficient */
netif_rx(skb);
}
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;
}
#define MGMT_FRAME_FIXED_PART_LENGTH 0x24
static inline int ieee80211_is_ofdm_rate(u8 rate)
{
switch (rate & ~IEEE80211_BASIC_RATE_MASK) {
case IEEE80211_OFDM_RATE_6MB:
case IEEE80211_OFDM_RATE_9MB:
case IEEE80211_OFDM_RATE_12MB:
case IEEE80211_OFDM_RATE_18MB:
case IEEE80211_OFDM_RATE_24MB:
case IEEE80211_OFDM_RATE_36MB:
case IEEE80211_OFDM_RATE_48MB:
case IEEE80211_OFDM_RATE_54MB:
return 1;
}
return 0;
}
static inline int ieee80211_network_init(struct ieee80211_device *ieee,
struct ieee80211_probe_response
*beacon,
struct ieee80211_network *network,
struct ieee80211_rx_stats *stats)
{
#ifdef CONFIG_IEEE80211_DEBUG
char rates_str[64];
char *p;
#endif
struct ieee80211_info_element *info_element;
u16 left;
u8 i;
/* Pull out fixed field data */
memcpy(network->bssid, beacon->header.addr3, ETH_ALEN);
network->capability = beacon->capability;
network->last_scanned = jiffies;
network->time_stamp[0] = beacon->time_stamp[0];
network->time_stamp[1] = beacon->time_stamp[1];
network->beacon_interval = beacon->beacon_interval;
/* Where to pull this? beacon->listen_interval; */
network->listen_interval = 0x0A;
network->rates_len = network->rates_ex_len = 0;
network->last_associate = 0;
network->ssid_len = 0;
network->flags = 0;
network->atim_window = 0;
if (stats->freq == IEEE80211_52GHZ_BAND) {
/* for A band (No DS info) */
network->channel = stats->received_channel;
} else
network->flags |= NETWORK_HAS_CCK;
network->wpa_ie_len = 0;
network->rsn_ie_len = 0;
info_element = &beacon->info_element;
left = stats->len - ((void *)info_element - (void *)beacon);
while (left >= sizeof(struct ieee80211_info_element_hdr)) {
if (sizeof(struct ieee80211_info_element_hdr) +
info_element->len > left) {
IEEE80211_DEBUG_SCAN
("SCAN: parse failed: info_element->len + 2 > left : info_element->len+2=%Zd left=%d.\n",
info_element->len +
sizeof(struct ieee80211_info_element), left);
return 1;
}
switch (info_element->id) {
case MFIE_TYPE_SSID:
if (ieee80211_is_empty_essid(info_element->data,
info_element->len)) {
network->flags |= NETWORK_EMPTY_ESSID;
break;
}
network->ssid_len = min(info_element->len,
(u8) IW_ESSID_MAX_SIZE);
memcpy(network->ssid, info_element->data,
network->ssid_len);
if (network->ssid_len < IW_ESSID_MAX_SIZE)
memset(network->ssid + network->ssid_len, 0,
IW_ESSID_MAX_SIZE - network->ssid_len);
IEEE80211_DEBUG_SCAN("MFIE_TYPE_SSID: '%s' len=%d.\n",
network->ssid, network->ssid_len);
break;
case MFIE_TYPE_RATES:
#ifdef CONFIG_IEEE80211_DEBUG
p = rates_str;
#endif
network->rates_len =
min(info_element->len, MAX_RATES_LENGTH);
for (i = 0; i < network->rates_len; i++) {
network->rates[i] = info_element->data[i];
#ifdef CONFIG_IEEE80211_DEBUG
p += snprintf(p,
sizeof(rates_str) - (p -
rates_str),
"%02X ", network->rates[i]);
#endif
if (ieee80211_is_ofdm_rate
(info_element->data[i])) {
network->flags |= NETWORK_HAS_OFDM;
if (info_element->data[i] &
IEEE80211_BASIC_RATE_MASK)
network->flags &=
~NETWORK_HAS_CCK;
}
}
IEEE80211_DEBUG_SCAN("MFIE_TYPE_RATES: '%s' (%d)\n",
rates_str, network->rates_len);
break;
case MFIE_TYPE_RATES_EX:
#ifdef CONFIG_IEEE80211_DEBUG
p = rates_str;
#endif
network->rates_ex_len =
min(info_element->len, MAX_RATES_EX_LENGTH);
for (i = 0; i < network->rates_ex_len; i++) {
network->rates_ex[i] = info_element->data[i];
#ifdef CONFIG_IEEE80211_DEBUG
p += snprintf(p,
sizeof(rates_str) - (p -
rates_str),
"%02X ", network->rates[i]);
#endif
if (ieee80211_is_ofdm_rate
(info_element->data[i])) {
network->flags |= NETWORK_HAS_OFDM;
if (info_element->data[i] &
IEEE80211_BASIC_RATE_MASK)
network->flags &=
~NETWORK_HAS_CCK;
}
}
IEEE80211_DEBUG_SCAN("MFIE_TYPE_RATES_EX: '%s' (%d)\n",
rates_str, network->rates_ex_len);
break;
case MFIE_TYPE_DS_SET:
IEEE80211_DEBUG_SCAN("MFIE_TYPE_DS_SET: %d\n",
info_element->data[0]);
if (stats->freq == IEEE80211_24GHZ_BAND)
network->channel = info_element->data[0];
break;
case MFIE_TYPE_FH_SET:
IEEE80211_DEBUG_SCAN("MFIE_TYPE_FH_SET: ignored\n");
break;
case MFIE_TYPE_CF_SET:
IEEE80211_DEBUG_SCAN("MFIE_TYPE_CF_SET: ignored\n");
break;
case MFIE_TYPE_TIM:
IEEE80211_DEBUG_SCAN("MFIE_TYPE_TIM: ignored\n");
break;
case MFIE_TYPE_IBSS_SET:
IEEE80211_DEBUG_SCAN("MFIE_TYPE_IBSS_SET: ignored\n");
break;
case MFIE_TYPE_CHALLENGE:
IEEE80211_DEBUG_SCAN("MFIE_TYPE_CHALLENGE: ignored\n");
break;
case MFIE_TYPE_GENERIC:
IEEE80211_DEBUG_SCAN("MFIE_TYPE_GENERIC: %d bytes\n",
info_element->len);
if (info_element->len >= 4 &&
info_element->data[0] == 0x00 &&
info_element->data[1] == 0x50 &&
info_element->data[2] == 0xf2 &&
info_element->data[3] == 0x01) {
network->wpa_ie_len = min(info_element->len + 2,
MAX_WPA_IE_LEN);
memcpy(network->wpa_ie, info_element,
network->wpa_ie_len);
}
break;
case MFIE_TYPE_RSN:
IEEE80211_DEBUG_SCAN("MFIE_TYPE_RSN: %d bytes\n",
info_element->len);
network->rsn_ie_len = min(info_element->len + 2,
MAX_WPA_IE_LEN);
memcpy(network->rsn_ie, info_element,
network->rsn_ie_len);
break;
default:
IEEE80211_DEBUG_SCAN("unsupported IE %d\n",
info_element->id);
break;
}
left -= sizeof(struct ieee80211_info_element_hdr) +
info_element->len;
info_element = (struct ieee80211_info_element *)
&info_element->data[info_element->len];
}
network->mode = 0;
if (stats->freq == IEEE80211_52GHZ_BAND)
network->mode = IEEE_A;
else {
if (network->flags & NETWORK_HAS_OFDM)
network->mode |= IEEE_G;
if (network->flags & NETWORK_HAS_CCK)
network->mode |= IEEE_B;
}
if (network->mode == 0) {
IEEE80211_DEBUG_SCAN("Filtered out '%s (" MAC_FMT ")' "
"network.\n",
escape_essid(network->ssid,
network->ssid_len),
MAC_ARG(network->bssid));
return 1;
}
if (ieee80211_is_empty_essid(network->ssid, network->ssid_len))
network->flags |= NETWORK_EMPTY_ESSID;
memcpy(&network->stats, stats, sizeof(network->stats));
return 0;
}
static inline int is_same_network(struct ieee80211_network *src,
struct ieee80211_network *dst)
{
/* A network is only a duplicate if the channel, BSSID, and ESSID
* all match. We treat all <hidden> with the same BSSID and channel
* as one network */
return ((src->ssid_len == dst->ssid_len) &&
(src->channel == dst->channel) &&
!memcmp(src->bssid, dst->bssid, ETH_ALEN) &&
!memcmp(src->ssid, dst->ssid, src->ssid_len));
}
static inline void update_network(struct ieee80211_network *dst,
struct ieee80211_network *src)
{
memcpy(&dst->stats, &src->stats, sizeof(struct ieee80211_rx_stats));
dst->capability = src->capability;
memcpy(dst->rates, src->rates, src->rates_len);
dst->rates_len = src->rates_len;
memcpy(dst->rates_ex, src->rates_ex, src->rates_ex_len);
dst->rates_ex_len = src->rates_ex_len;
dst->mode = src->mode;
dst->flags = src->flags;
dst->time_stamp[0] = src->time_stamp[0];
dst->time_stamp[1] = src->time_stamp[1];
dst->beacon_interval = src->beacon_interval;
dst->listen_interval = src->listen_interval;
dst->atim_window = src->atim_window;
memcpy(dst->wpa_ie, src->wpa_ie, src->wpa_ie_len);
dst->wpa_ie_len = src->wpa_ie_len;
memcpy(dst->rsn_ie, src->rsn_ie, src->rsn_ie_len);
dst->rsn_ie_len = src->rsn_ie_len;
dst->last_scanned = jiffies;
/* dst->last_associate is not overwritten */
}
static inline void ieee80211_process_probe_response(struct ieee80211_device
*ieee,
struct
ieee80211_probe_response
*beacon,
struct ieee80211_rx_stats
*stats)
{
struct ieee80211_network network;
struct ieee80211_network *target;
struct ieee80211_network *oldest = NULL;
#ifdef CONFIG_IEEE80211_DEBUG
struct ieee80211_info_element *info_element = &beacon->info_element;
#endif
unsigned long flags;
IEEE80211_DEBUG_SCAN("'%s' (" MAC_FMT
"): %c%c%c%c %c%c%c%c-%c%c%c%c %c%c%c%c\n",
escape_essid(info_element->data,
info_element->len),
MAC_ARG(beacon->header.addr3),
(beacon->capability & (1 << 0xf)) ? '1' : '0',
(beacon->capability & (1 << 0xe)) ? '1' : '0',
(beacon->capability & (1 << 0xd)) ? '1' : '0',
(beacon->capability & (1 << 0xc)) ? '1' : '0',
(beacon->capability & (1 << 0xb)) ? '1' : '0',
(beacon->capability & (1 << 0xa)) ? '1' : '0',
(beacon->capability & (1 << 0x9)) ? '1' : '0',
(beacon->capability & (1 << 0x8)) ? '1' : '0',
(beacon->capability & (1 << 0x7)) ? '1' : '0',
(beacon->capability & (1 << 0x6)) ? '1' : '0',
(beacon->capability & (1 << 0x5)) ? '1' : '0',
(beacon->capability & (1 << 0x4)) ? '1' : '0',
(beacon->capability & (1 << 0x3)) ? '1' : '0',
(beacon->capability & (1 << 0x2)) ? '1' : '0',
(beacon->capability & (1 << 0x1)) ? '1' : '0',
(beacon->capability & (1 << 0x0)) ? '1' : '0');
if (ieee80211_network_init(ieee, beacon, &network, stats)) {
IEEE80211_DEBUG_SCAN("Dropped '%s' (" MAC_FMT ") via %s.\n",
escape_essid(info_element->data,
info_element->len),
MAC_ARG(beacon->header.addr3),
WLAN_FC_GET_STYPE(beacon->header.
frame_ctl) ==
IEEE80211_STYPE_PROBE_RESP ?
"PROBE RESPONSE" : "BEACON");
return;
}
/* The network parsed correctly -- so now we scan our known networks
* to see if we can find it in our list.
*
* NOTE: This search is definitely not optimized. Once its doing
* the "right thing" we'll optimize it for efficiency if
* necessary */
/* Search for this entry in the list and update it if it is
* already there. */
spin_lock_irqsave(&ieee->lock, flags);
list_for_each_entry(target, &ieee->network_list, list) {
if (is_same_network(target, &network))
break;
if ((oldest == NULL) ||
(target->last_scanned < oldest->last_scanned))
oldest = target;
}
/* If we didn't find a match, then get a new network slot to initialize
* with this beacon's information */
if (&target->list == &ieee->network_list) {
if (list_empty(&ieee->network_free_list)) {
/* If there are no more slots, expire the oldest */
list_del(&oldest->list);
target = oldest;
IEEE80211_DEBUG_SCAN("Expired '%s' (" MAC_FMT ") from "
"network list.\n",
escape_essid(target->ssid,
target->ssid_len),
MAC_ARG(target->bssid));
} else {
/* Otherwise just pull from the free list */
target = list_entry(ieee->network_free_list.next,
struct ieee80211_network, list);
list_del(ieee->network_free_list.next);
}
#ifdef CONFIG_IEEE80211_DEBUG
IEEE80211_DEBUG_SCAN("Adding '%s' (" MAC_FMT ") via %s.\n",
escape_essid(network.ssid,
network.ssid_len),
MAC_ARG(network.bssid),
WLAN_FC_GET_STYPE(beacon->header.
frame_ctl) ==
IEEE80211_STYPE_PROBE_RESP ?
"PROBE RESPONSE" : "BEACON");
#endif
memcpy(target, &network, sizeof(*target));
list_add_tail(&target->list, &ieee->network_list);
} else {
IEEE80211_DEBUG_SCAN("Updating '%s' (" MAC_FMT ") via %s.\n",
escape_essid(target->ssid,
target->ssid_len),
MAC_ARG(target->bssid),
WLAN_FC_GET_STYPE(beacon->header.
frame_ctl) ==
IEEE80211_STYPE_PROBE_RESP ?
"PROBE RESPONSE" : "BEACON");
update_network(target, &network);
}
spin_unlock_irqrestore(&ieee->lock, flags);
}
void ieee80211_rx_mgt(struct ieee80211_device *ieee,
struct ieee80211_hdr *header,
struct ieee80211_rx_stats *stats)
{
switch (WLAN_FC_GET_STYPE(header->frame_ctl)) {
case IEEE80211_STYPE_ASSOC_RESP:
IEEE80211_DEBUG_MGMT("received ASSOCIATION RESPONSE (%d)\n",
WLAN_FC_GET_STYPE(header->frame_ctl));
break;
case IEEE80211_STYPE_REASSOC_RESP:
IEEE80211_DEBUG_MGMT("received REASSOCIATION RESPONSE (%d)\n",
WLAN_FC_GET_STYPE(header->frame_ctl));
break;
case IEEE80211_STYPE_PROBE_RESP:
IEEE80211_DEBUG_MGMT("received PROBE RESPONSE (%d)\n",
WLAN_FC_GET_STYPE(header->frame_ctl));
IEEE80211_DEBUG_SCAN("Probe response\n");
ieee80211_process_probe_response(ieee,
(struct
ieee80211_probe_response *)
header, stats);
break;
case IEEE80211_STYPE_BEACON:
IEEE80211_DEBUG_MGMT("received BEACON (%d)\n",
WLAN_FC_GET_STYPE(header->frame_ctl));
IEEE80211_DEBUG_SCAN("Beacon\n");
ieee80211_process_probe_response(ieee,
(struct
ieee80211_probe_response *)
header, stats);
break;
default:
IEEE80211_DEBUG_MGMT("received UNKNOWN (%d)\n",
WLAN_FC_GET_STYPE(header->frame_ctl));
IEEE80211_WARNING("%s: Unknown management packet: %d\n",
ieee->dev->name,
WLAN_FC_GET_STYPE(header->frame_ctl));
break;
}
}
EXPORT_SYMBOL(ieee80211_rx_mgt);
EXPORT_SYMBOL(ieee80211_rx);