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linux/drivers/net/wireless/hostap/hostap_80211_rx.c

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#include <linux/etherdevice.h>
#include <linux/slab.h>
#include <net/lib80211.h>
#include <linux/if_arp.h>
#include "hostap_80211.h"
#include "hostap.h"
#include "hostap_ap.h"
/* 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) */
void hostap_dump_rx_80211(const char *name, struct sk_buff *skb,
struct hostap_80211_rx_status *rx_stats)
{
struct ieee80211_hdr *hdr;
u16 fc;
hdr = (struct ieee80211_hdr *) skb->data;
printk(KERN_DEBUG "%s: RX signal=%d noise=%d rate=%d len=%d "
"jiffies=%ld\n",
name, rx_stats->signal, rx_stats->noise, rx_stats->rate,
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, (fc & IEEE80211_FCTL_FTYPE) >> 2,
(fc & IEEE80211_FCTL_STYPE) >> 4,
fc & IEEE80211_FCTL_TODS ? " [ToDS]" : "",
fc & IEEE80211_FCTL_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=%pM", hdr->addr1);
printk(" A2=%pM", hdr->addr2);
printk(" A3=%pM", hdr->addr3);
if (skb->len >= 30)
printk(" A4=%pM", hdr->addr4);
printk("\n");
}
/* Send RX frame to netif with 802.11 (and possible prism) header.
* Called from hardware or software IRQ context. */
int prism2_rx_80211(struct net_device *dev, struct sk_buff *skb,
struct hostap_80211_rx_status *rx_stats, int type)
{
struct hostap_interface *iface;
local_info_t *local;
int hdrlen, phdrlen, head_need, tail_need;
u16 fc;
int prism_header, ret;
struct ieee80211_hdr *fhdr;
iface = netdev_priv(dev);
local = iface->local;
if (dev->type == ARPHRD_IEEE80211_PRISM) {
if (local->monitor_type == PRISM2_MONITOR_PRISM) {
prism_header = 1;
phdrlen = sizeof(struct linux_wlan_ng_prism_hdr);
} else { /* local->monitor_type == PRISM2_MONITOR_CAPHDR */
prism_header = 2;
phdrlen = sizeof(struct linux_wlan_ng_cap_hdr);
}
} else if (dev->type == ARPHRD_IEEE80211_RADIOTAP) {
prism_header = 3;
phdrlen = sizeof(struct hostap_radiotap_rx);
} else {
prism_header = 0;
phdrlen = 0;
}
fhdr = (struct ieee80211_hdr *) skb->data;
fc = le16_to_cpu(fhdr->frame_control);
if (type == PRISM2_RX_MGMT && (fc & IEEE80211_FCTL_VERS)) {
printk(KERN_DEBUG "%s: dropped management frame with header "
"version %d\n", dev->name, fc & IEEE80211_FCTL_VERS);
dev_kfree_skb_any(skb);
return 0;
}
hdrlen = hostap_80211_get_hdrlen(fhdr->frame_control);
/* check if there is enough room for extra data; if not, expand skb
* buffer to be large enough for the changes */
head_need = phdrlen;
tail_need = 0;
#ifdef PRISM2_ADD_BOGUS_CRC
tail_need += 4;
#endif /* PRISM2_ADD_BOGUS_CRC */
head_need -= skb_headroom(skb);
tail_need -= skb_tailroom(skb);
if (head_need > 0 || tail_need > 0) {
if (pskb_expand_head(skb, head_need > 0 ? head_need : 0,
tail_need > 0 ? tail_need : 0,
GFP_ATOMIC)) {
printk(KERN_DEBUG "%s: prism2_rx_80211 failed to "
"reallocate skb buffer\n", dev->name);
dev_kfree_skb_any(skb);
return 0;
}
}
/* We now have an skb with enough head and tail room, so just insert
* the extra data */
#ifdef PRISM2_ADD_BOGUS_CRC
memset(skb_put(skb, 4), 0xff, 4); /* Prism2 strips CRC */
#endif /* PRISM2_ADD_BOGUS_CRC */
if (prism_header == 1) {
struct linux_wlan_ng_prism_hdr *hdr;
hdr = (struct linux_wlan_ng_prism_hdr *)
skb_push(skb, phdrlen);
memset(hdr, 0, phdrlen);
hdr->msgcode = LWNG_CAP_DID_BASE;
hdr->msglen = sizeof(*hdr);
memcpy(hdr->devname, dev->name, sizeof(hdr->devname));
#define LWNG_SETVAL(f,i,s,l,d) \
hdr->f.did = LWNG_CAP_DID_BASE | (i << 12); \
hdr->f.status = s; hdr->f.len = l; hdr->f.data = d
LWNG_SETVAL(hosttime, 1, 0, 4, jiffies);
LWNG_SETVAL(mactime, 2, 0, 4, rx_stats->mac_time);
LWNG_SETVAL(channel, 3, 1 /* no value */, 4, 0);
LWNG_SETVAL(rssi, 4, 1 /* no value */, 4, 0);
LWNG_SETVAL(sq, 5, 1 /* no value */, 4, 0);
LWNG_SETVAL(signal, 6, 0, 4, rx_stats->signal);
LWNG_SETVAL(noise, 7, 0, 4, rx_stats->noise);
LWNG_SETVAL(rate, 8, 0, 4, rx_stats->rate / 5);
LWNG_SETVAL(istx, 9, 0, 4, 0);
LWNG_SETVAL(frmlen, 10, 0, 4, skb->len - phdrlen);
#undef LWNG_SETVAL
} else if (prism_header == 2) {
struct linux_wlan_ng_cap_hdr *hdr;
hdr = (struct linux_wlan_ng_cap_hdr *)
skb_push(skb, phdrlen);
memset(hdr, 0, phdrlen);
hdr->version = htonl(LWNG_CAPHDR_VERSION);
hdr->length = htonl(phdrlen);
hdr->mactime = __cpu_to_be64(rx_stats->mac_time);
hdr->hosttime = __cpu_to_be64(jiffies);
hdr->phytype = htonl(4); /* dss_dot11_b */
hdr->channel = htonl(local->channel);
hdr->datarate = htonl(rx_stats->rate);
hdr->antenna = htonl(0); /* unknown */
hdr->priority = htonl(0); /* unknown */
hdr->ssi_type = htonl(3); /* raw */
hdr->ssi_signal = htonl(rx_stats->signal);
hdr->ssi_noise = htonl(rx_stats->noise);
hdr->preamble = htonl(0); /* unknown */
hdr->encoding = htonl(1); /* cck */
} else if (prism_header == 3) {
struct hostap_radiotap_rx *hdr;
hdr = (struct hostap_radiotap_rx *)skb_push(skb, phdrlen);
memset(hdr, 0, phdrlen);
hdr->hdr.it_len = cpu_to_le16(phdrlen);
hdr->hdr.it_present =
cpu_to_le32((1 << IEEE80211_RADIOTAP_TSFT) |
(1 << IEEE80211_RADIOTAP_CHANNEL) |
(1 << IEEE80211_RADIOTAP_RATE) |
(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL) |
(1 << IEEE80211_RADIOTAP_DBM_ANTNOISE));
hdr->tsft = cpu_to_le64(rx_stats->mac_time);
hdr->chan_freq = cpu_to_le16(freq_list[local->channel - 1]);
hdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_CCK |
IEEE80211_CHAN_2GHZ);
hdr->rate = rx_stats->rate / 5;
hdr->dbm_antsignal = rx_stats->signal;
hdr->dbm_antnoise = rx_stats->noise;
}
ret = skb->len - phdrlen;
skb->dev = dev;
skb_reset_mac_header(skb);
skb_pull(skb, hdrlen);
if (prism_header)
skb_pull(skb, phdrlen);
skb->pkt_type = PACKET_OTHERHOST;
skb->protocol = cpu_to_be16(ETH_P_802_2);
memset(skb->cb, 0, sizeof(skb->cb));
netif_rx(skb);
return ret;
}
/* Called only as a tasklet (software IRQ) */
static void monitor_rx(struct net_device *dev, struct sk_buff *skb,
struct hostap_80211_rx_status *rx_stats)
{
int len;
len = prism2_rx_80211(dev, skb, rx_stats, PRISM2_RX_MONITOR);
dev->stats.rx_packets++;
dev->stats.rx_bytes += len;
}
/* Called only as a tasklet (software IRQ) */
static struct prism2_frag_entry *
prism2_frag_cache_find(local_info_t *local, unsigned int seq,
unsigned int frag, u8 *src, u8 *dst)
{
struct prism2_frag_entry *entry;
int i;
for (i = 0; i < PRISM2_FRAG_CACHE_LEN; i++) {
entry = &local->frag_cache[i];
if (entry->skb != NULL &&
time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
printk(KERN_DEBUG "%s: expiring fragment cache entry "
"seq=%u last_frag=%u\n",
local->dev->name, entry->seq, entry->last_frag);
dev_kfree_skb(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 *
prism2_frag_cache_get(local_info_t *local, struct ieee80211_hdr *hdr)
{
struct sk_buff *skb = NULL;
u16 sc;
unsigned int frag, seq;
struct prism2_frag_entry *entry;
sc = le16_to_cpu(hdr->seq_ctrl);
frag = sc & IEEE80211_SCTL_FRAG;
seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
if (frag == 0) {
/* Reserve enough space to fit maximum frame length */
skb = dev_alloc_skb(local->dev->mtu +
sizeof(struct ieee80211_hdr) +
8 /* LLC */ +
2 /* alignment */ +
8 /* WEP */ + ETH_ALEN /* WDS */);
if (skb == NULL)
return NULL;
entry = &local->frag_cache[local->frag_next_idx];
local->frag_next_idx++;
if (local->frag_next_idx >= PRISM2_FRAG_CACHE_LEN)
local->frag_next_idx = 0;
if (entry->skb != NULL)
dev_kfree_skb(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 = prism2_frag_cache_find(local, 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 prism2_frag_cache_invalidate(local_info_t *local,
struct ieee80211_hdr *hdr)
{
u16 sc;
unsigned int seq;
struct prism2_frag_entry *entry;
sc = le16_to_cpu(hdr->seq_ctrl);
seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
entry = prism2_frag_cache_find(local, seq, -1, hdr->addr2, hdr->addr1);
if (entry == NULL) {
printk(KERN_DEBUG "%s: could not invalidate fragment cache "
"entry (seq=%u)\n",
local->dev->name, seq);
return -1;
}
entry->skb = NULL;
return 0;
}
static struct hostap_bss_info *__hostap_get_bss(local_info_t *local, u8 *bssid,
u8 *ssid, size_t ssid_len)
{
struct list_head *ptr;
struct hostap_bss_info *bss;
list_for_each(ptr, &local->bss_list) {
bss = list_entry(ptr, struct hostap_bss_info, list);
if (memcmp(bss->bssid, bssid, ETH_ALEN) == 0 &&
(ssid == NULL ||
(ssid_len == bss->ssid_len &&
memcmp(ssid, bss->ssid, ssid_len) == 0))) {
list_move(&bss->list, &local->bss_list);
return bss;
}
}
return NULL;
}
static struct hostap_bss_info *__hostap_add_bss(local_info_t *local, u8 *bssid,
u8 *ssid, size_t ssid_len)
{
struct hostap_bss_info *bss;
if (local->num_bss_info >= HOSTAP_MAX_BSS_COUNT) {
bss = list_entry(local->bss_list.prev,
struct hostap_bss_info, list);
list_del(&bss->list);
local->num_bss_info--;
} else {
bss = kmalloc(sizeof(*bss), GFP_ATOMIC);
if (bss == NULL)
return NULL;
}
memset(bss, 0, sizeof(*bss));
memcpy(bss->bssid, bssid, ETH_ALEN);
memcpy(bss->ssid, ssid, ssid_len);
bss->ssid_len = ssid_len;
local->num_bss_info++;
list_add(&bss->list, &local->bss_list);
return bss;
}
static void __hostap_expire_bss(local_info_t *local)
{
struct hostap_bss_info *bss;
while (local->num_bss_info > 0) {
bss = list_entry(local->bss_list.prev,
struct hostap_bss_info, list);
if (!time_after(jiffies, bss->last_update + 60 * HZ))
break;
list_del(&bss->list);
local->num_bss_info--;
kfree(bss);
}
}
/* Both IEEE 802.11 Beacon and Probe Response frames have similar structure, so
* the same routine can be used to parse both of them. */
static void hostap_rx_sta_beacon(local_info_t *local, struct sk_buff *skb,
int stype)
{
struct hostap_ieee80211_mgmt *mgmt;
int left, chan = 0;
u8 *pos;
u8 *ssid = NULL, *wpa = NULL, *rsn = NULL;
size_t ssid_len = 0, wpa_len = 0, rsn_len = 0;
struct hostap_bss_info *bss;
if (skb->len < IEEE80211_MGMT_HDR_LEN + sizeof(mgmt->u.beacon))
return;
mgmt = (struct hostap_ieee80211_mgmt *) skb->data;
pos = mgmt->u.beacon.variable;
left = skb->len - (pos - skb->data);
while (left >= 2) {
if (2 + pos[1] > left)
return; /* parse failed */
switch (*pos) {
case WLAN_EID_SSID:
ssid = pos + 2;
ssid_len = pos[1];
break;
case WLAN_EID_GENERIC:
if (pos[1] >= 4 &&
pos[2] == 0x00 && pos[3] == 0x50 &&
pos[4] == 0xf2 && pos[5] == 1) {
wpa = pos;
wpa_len = pos[1] + 2;
}
break;
case WLAN_EID_RSN:
rsn = pos;
rsn_len = pos[1] + 2;
break;
case WLAN_EID_DS_PARAMS:
if (pos[1] >= 1)
chan = pos[2];
break;
}
left -= 2 + pos[1];
pos += 2 + pos[1];
}
if (wpa_len > MAX_WPA_IE_LEN)
wpa_len = MAX_WPA_IE_LEN;
if (rsn_len > MAX_WPA_IE_LEN)
rsn_len = MAX_WPA_IE_LEN;
if (ssid_len > sizeof(bss->ssid))
ssid_len = sizeof(bss->ssid);
spin_lock(&local->lock);
bss = __hostap_get_bss(local, mgmt->bssid, ssid, ssid_len);
if (bss == NULL)
bss = __hostap_add_bss(local, mgmt->bssid, ssid, ssid_len);
if (bss) {
bss->last_update = jiffies;
bss->count++;
bss->capab_info = le16_to_cpu(mgmt->u.beacon.capab_info);
if (wpa) {
memcpy(bss->wpa_ie, wpa, wpa_len);
bss->wpa_ie_len = wpa_len;
} else
bss->wpa_ie_len = 0;
if (rsn) {
memcpy(bss->rsn_ie, rsn, rsn_len);
bss->rsn_ie_len = rsn_len;
} else
bss->rsn_ie_len = 0;
bss->chan = chan;
}
__hostap_expire_bss(local);
spin_unlock(&local->lock);
}
static int
hostap_rx_frame_mgmt(local_info_t *local, struct sk_buff *skb,
struct hostap_80211_rx_status *rx_stats, u16 type,
u16 stype)
{
if (local->iw_mode == IW_MODE_MASTER)
hostap_update_sta_ps(local, (struct ieee80211_hdr *) skb->data);
if (local->hostapd && type == IEEE80211_FTYPE_MGMT) {
if (stype == IEEE80211_STYPE_BEACON &&
local->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 */
local->apdevstats.rx_packets++;
local->apdevstats.rx_bytes += skb->len;
if (local->apdev == NULL)
return -1;
prism2_rx_80211(local->apdev, skb, rx_stats, PRISM2_RX_MGMT);
return 0;
}
if (local->iw_mode == IW_MODE_MASTER) {
if (type != IEEE80211_FTYPE_MGMT &&
type != IEEE80211_FTYPE_CTL) {
printk(KERN_DEBUG "%s: unknown management frame "
"(type=0x%02x, stype=0x%02x) dropped\n",
skb->dev->name, type >> 2, stype >> 4);
return -1;
}
hostap_rx(skb->dev, skb, rx_stats);
return 0;
} else if (type == IEEE80211_FTYPE_MGMT &&
(stype == IEEE80211_STYPE_BEACON ||
stype == IEEE80211_STYPE_PROBE_RESP)) {
hostap_rx_sta_beacon(local, skb, stype);
return -1;
} else if (type == IEEE80211_FTYPE_MGMT &&
(stype == IEEE80211_STYPE_ASSOC_RESP ||
stype == IEEE80211_STYPE_REASSOC_RESP)) {
/* Ignore (Re)AssocResp silently since these are not currently
* needed but are still received when WPA/RSN mode is enabled.
*/
return -1;
} else {
printk(KERN_DEBUG "%s: hostap_rx_frame_mgmt: dropped unhandled"
" management frame in non-Host AP mode (type=%d:%d)\n",
skb->dev->name, type >> 2, stype >> 4);
return -1;
}
}
/* Called only as a tasklet (software IRQ) */
static struct net_device *prism2_rx_get_wds(local_info_t *local,
u8 *addr)
{
struct hostap_interface *iface = NULL;
struct list_head *ptr;
read_lock_bh(&local->iface_lock);
list_for_each(ptr, &local->hostap_interfaces) {
iface = list_entry(ptr, struct hostap_interface, list);
if (iface->type == HOSTAP_INTERFACE_WDS &&
memcmp(iface->u.wds.remote_addr, addr, ETH_ALEN) == 0)
break;
iface = NULL;
}
read_unlock_bh(&local->iface_lock);
return iface ? iface->dev : NULL;
}
static int
hostap_rx_frame_wds(local_info_t *local, struct ieee80211_hdr *hdr, u16 fc,
struct net_device **wds)
{
/* FIX: is this really supposed to accept WDS frames only in Master
* mode? What about Repeater or Managed with WDS frames? */
if ((fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) !=
(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS) &&
(local->iw_mode != IW_MODE_MASTER || !(fc & IEEE80211_FCTL_TODS)))
return 0; /* not a WDS frame */
/* Possible WDS frame: either IEEE 802.11 compliant (if FromDS)
* or own non-standard frame with 4th address after payload */
if (memcmp(hdr->addr1, local->dev->dev_addr, ETH_ALEN) != 0 &&
(hdr->addr1[0] != 0xff || hdr->addr1[1] != 0xff ||
hdr->addr1[2] != 0xff || hdr->addr1[3] != 0xff ||
hdr->addr1[4] != 0xff || hdr->addr1[5] != 0xff)) {
/* RA (or BSSID) is not ours - drop */
PDEBUG(DEBUG_EXTRA2, "%s: received WDS frame with "
"not own or broadcast %s=%pM\n",
local->dev->name,
fc & IEEE80211_FCTL_FROMDS ? "RA" : "BSSID",
hdr->addr1);
return -1;
}
/* check if the frame came from a registered WDS connection */
*wds = prism2_rx_get_wds(local, hdr->addr2);
if (*wds == NULL && fc & IEEE80211_FCTL_FROMDS &&
(local->iw_mode != IW_MODE_INFRA ||
!(local->wds_type & HOSTAP_WDS_AP_CLIENT) ||
memcmp(hdr->addr2, local->bssid, ETH_ALEN) != 0)) {
/* require that WDS link has been registered with TA or the
* frame is from current AP when using 'AP client mode' */
PDEBUG(DEBUG_EXTRA, "%s: received WDS[4 addr] frame "
"from unknown TA=%pM\n",
local->dev->name, hdr->addr2);
if (local->ap && local->ap->autom_ap_wds)
hostap_wds_link_oper(local, hdr->addr2, WDS_ADD);
return -1;
}
if (*wds && !(fc & IEEE80211_FCTL_FROMDS) && local->ap &&
hostap_is_sta_assoc(local->ap, hdr->addr2)) {
/* STA is actually associated with us even though it has a
* registered WDS link. Assume it is in 'AP client' mode.
* Since this is a 3-addr frame, assume it is not (bogus) WDS
* frame and process it like any normal ToDS frame from
* associated STA. */
*wds = NULL;
}
return 0;
}
static int hostap_is_eapol_frame(local_info_t *local, struct sk_buff *skb)
{
struct net_device *dev = local->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_control);
/* 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) */
static int
hostap_rx_frame_decrypt(local_info_t *local, struct sk_buff *skb,
struct lib80211_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 = hostap_80211_get_hdrlen(hdr->frame_control);
if (local->tkip_countermeasures &&
strcmp(crypt->ops->name, "TKIP") == 0) {
if (net_ratelimit()) {
printk(KERN_DEBUG "%s: TKIP countermeasures: dropped "
"received packet from %pM\n",
local->dev->name, hdr->addr2);
}
return -1;
}
atomic_inc(&crypt->refcnt);
res = crypt->ops->decrypt_mpdu(skb, hdrlen, crypt->priv);
atomic_dec(&crypt->refcnt);
if (res < 0) {
printk(KERN_DEBUG "%s: decryption failed (SA=%pM) res=%d\n",
local->dev->name, hdr->addr2, res);
local->comm_tallies.rx_discards_wep_undecryptable++;
return -1;
}
return res;
}
/* Called only as a tasklet (software IRQ) */
static int
hostap_rx_frame_decrypt_msdu(local_info_t *local, struct sk_buff *skb,
int keyidx, struct lib80211_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 = hostap_80211_get_hdrlen(hdr->frame_control);
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",
local->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). */
void hostap_80211_rx(struct net_device *dev, struct sk_buff *skb,
struct hostap_80211_rx_status *rx_stats)
{
struct hostap_interface *iface;
local_info_t *local;
struct ieee80211_hdr *hdr;
size_t hdrlen;
u16 fc, type, stype, sc;
struct net_device *wds = NULL;
unsigned int frag;
u8 *payload;
struct sk_buff *skb2 = NULL;
u16 ethertype;
int frame_authorized = 0;
int from_assoc_ap = 0;
u8 dst[ETH_ALEN];
u8 src[ETH_ALEN];
struct lib80211_crypt_data *crypt = NULL;
void *sta = NULL;
int keyidx = 0;
iface = netdev_priv(dev);
local = iface->local;
iface->stats.rx_packets++;
iface->stats.rx_bytes += skb->len;
/* dev is the master radio device; change this to be the default
* virtual interface (this may be changed to WDS device below) */
dev = local->ddev;
iface = netdev_priv(dev);
hdr = (struct ieee80211_hdr *) skb->data;
if (skb->len < 10)
goto rx_dropped;
fc = le16_to_cpu(hdr->frame_control);
type = fc & IEEE80211_FCTL_FTYPE;
stype = fc & IEEE80211_FCTL_STYPE;
sc = le16_to_cpu(hdr->seq_ctrl);
frag = sc & IEEE80211_SCTL_FRAG;
hdrlen = hostap_80211_get_hdrlen(hdr->frame_control);
/* 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 = IW_QUAL_LEVEL_UPDATED | IW_QUAL_NOISE_UPDATED
| IW_QUAL_QUAL_INVALID | IW_QUAL_DBM;
/* Update spy records */
wireless_spy_update(dev, hdr->addr2, &wstats);
}
#endif /* IW_WIRELESS_SPY */
hostap_update_rx_stats(local->ap, hdr, rx_stats);
if (local->iw_mode == IW_MODE_MONITOR) {
monitor_rx(dev, skb, rx_stats);
return;
}
if (local->host_decrypt) {
int idx = 0;
if (skb->len >= hdrlen + 3)
idx = skb->data[hdrlen + 3] >> 6;
crypt = local->crypt_info.crypt[idx];
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);
/* 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)) {
#if 0
/* 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. */
printk(KERN_DEBUG "%s: WEP decryption failed (not set)"
" (SA=%pM)\n",
local->dev->name, hdr->addr2);
#endif
local->comm_tallies.rx_discards_wep_undecryptable++;
goto rx_dropped;
}
}
if (type != IEEE80211_FTYPE_DATA) {
if (type == IEEE80211_FTYPE_MGMT &&
stype == IEEE80211_STYPE_AUTH &&
fc & IEEE80211_FCTL_PROTECTED && local->host_decrypt &&
(keyidx = hostap_rx_frame_decrypt(local, 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 (hostap_rx_frame_mgmt(local, skb, rx_stats, type, stype))
goto rx_dropped;
else
goto rx_exit;
}
/* Data frame - extract src/dst addresses */
if (skb->len < IEEE80211_DATA_HDR3_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_DATA_HDR4_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;
}
if (hostap_rx_frame_wds(local, hdr, fc, &wds))
goto rx_dropped;
if (wds)
skb->dev = dev = wds;
if (local->iw_mode == IW_MODE_MASTER && !wds &&
(fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) ==
IEEE80211_FCTL_FROMDS &&
local->stadev &&
memcmp(hdr->addr2, local->assoc_ap_addr, ETH_ALEN) == 0) {
/* Frame from BSSID of the AP for which we are a client */
skb->dev = dev = local->stadev;
from_assoc_ap = 1;
}
if ((local->iw_mode == IW_MODE_MASTER ||
local->iw_mode == IW_MODE_REPEAT) &&
!from_assoc_ap) {
switch (hostap_handle_sta_rx(local, 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;
}
}
/* 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)
printk(KERN_DEBUG "%s: RX: dropped data frame "
"with no data (type=0x%02x, subtype=0x%02x)\n",
dev->name, type >> 2, stype >> 4);
goto rx_dropped;
}
/* skb: hdr + (possibly fragmented, possibly encrypted) payload */
if (local->host_decrypt && (fc & IEEE80211_FCTL_PROTECTED) &&
(keyidx = hostap_rx_frame_decrypt(local, skb, crypt)) < 0)
goto rx_dropped;
hdr = (struct ieee80211_hdr *) skb->data;
/* skb: hdr + (possibly fragmented) plaintext payload */
if (local->host_decrypt && (fc & IEEE80211_FCTL_PROTECTED) &&
(frag != 0 || (fc & IEEE80211_FCTL_MOREFRAGS))) {
int flen;
struct sk_buff *frag_skb =
prism2_frag_cache_get(local, hdr);
if (!frag_skb) {
printk(KERN_DEBUG "%s: Rx cannot get skb from "
"fragment cache (morefrag=%d seq=%u frag=%u)\n",
dev->name, (fc & IEEE80211_FCTL_MOREFRAGS) != 0,
(sc & IEEE80211_SCTL_SEQ) >> 4, 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);
prism2_frag_cache_invalidate(local, 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(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;
prism2_frag_cache_invalidate(local, hdr);
}
/* skb: hdr + (possible reassembled) full MSDU payload; possibly still
* encrypted/authenticated */
if (local->host_decrypt && (fc & IEEE80211_FCTL_PROTECTED) &&
hostap_rx_frame_decrypt_msdu(local, skb, keyidx, crypt))
goto rx_dropped;
hdr = (struct ieee80211_hdr *) skb->data;
if (crypt && !(fc & IEEE80211_FCTL_PROTECTED) && !local->open_wep) {
if (local->ieee_802_1x &&
hostap_is_eapol_frame(local, skb)) {
/* pass unencrypted EAPOL frames even if encryption is
* configured */
PDEBUG(DEBUG_EXTRA2, "%s: RX: IEEE 802.1X - passing "
"unencrypted EAPOL frame\n", local->dev->name);
} else {
printk(KERN_DEBUG "%s: encryption configured, but RX "
"frame not encrypted (SA=%pM)\n",
local->dev->name, hdr->addr2);
goto rx_dropped;
}
}
if (local->drop_unencrypted && !(fc & IEEE80211_FCTL_PROTECTED) &&
!hostap_is_eapol_frame(local, skb)) {
if (net_ratelimit()) {
printk(KERN_DEBUG "%s: dropped unencrypted RX data "
"frame from %pM (drop_unencrypted=1)\n",
dev->name, hdr->addr2);
}
goto rx_dropped;
}
/* skb: hdr + (possible reassembled) full plaintext payload */
payload = skb->data + hdrlen;
ethertype = (payload[6] << 8) | payload[7];
/* If IEEE 802.1X is used, check whether the port is authorized to send
* the received frame. */
if (local->ieee_802_1x && local->iw_mode == IW_MODE_MASTER) {
if (ethertype == ETH_P_PAE) {
PDEBUG(DEBUG_EXTRA2, "%s: RX: IEEE 802.1X frame\n",
dev->name);
if (local->hostapd && local->apdev) {
/* Send IEEE 802.1X frames to the user
* space daemon for processing */
prism2_rx_80211(local->apdev, skb, rx_stats,
PRISM2_RX_MGMT);
local->apdevstats.rx_packets++;
local->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;
}
}
/* convert hdr + possible LLC headers into Ethernet header */
if (skb->len - hdrlen >= 8 &&
((memcmp(payload, rfc1042_header, 6) == 0 &&
ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
memcmp(payload, bridge_tunnel_header, 6) == 0)) {
/* remove RFC1042 or Bridge-Tunnel encapsulation and
* replace EtherType */
skb_pull(skb, hdrlen + 6);
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);
}
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_from_linear_data_offset(skb, skb->len - ETH_ALEN,
skb->data + ETH_ALEN,
ETH_ALEN);
skb_trim(skb, skb->len - ETH_ALEN);
}
dev->stats.rx_packets++;
dev->stats.rx_bytes += skb->len;
if (local->iw_mode == IW_MODE_MASTER && !wds &&
local->ap->bridge_packets) {
if (dst[0] & 0x01) {
/* copy multicast frame both to the higher layers and
* to the wireless media */
local->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_authorized(local->ap, dst)) {
/* send frame directly to the associated STA using
* wireless media and not passing to higher layers */
local->ap->bridged_unicast++;
skb2 = skb;
skb = NULL;
}
}
if (skb2 != NULL) {
/* send to wireless media */
skb2->dev = dev;
skb2->protocol = cpu_to_be16(ETH_P_802_3);
skb_reset_mac_header(skb2);
skb_reset_network_header(skb2);
/* skb2->network_header += ETH_HLEN; */
dev_queue_xmit(skb2);
}
if (skb) {
skb->protocol = eth_type_trans(skb, dev);
memset(skb->cb, 0, sizeof(skb->cb));
netif_rx(skb);
}
rx_exit:
if (sta)
hostap_handle_sta_release(sta);
return;
rx_dropped:
dev_kfree_skb(skb);
dev->stats.rx_dropped++;
goto rx_exit;
}
EXPORT_SYMBOL(hostap_80211_rx);
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