This patch restructures the Rx handlers chain by incorporating previously
handlers ieee80211_rx_h_802_1x_pae and ieee80211_rx_h_drop_unencrypted
into ieee80211_rx_h_data, already in 802.3 form. this scheme follows more
precisely after the IEEE802.11 data plane archituecture, and will prevent
code duplication to IEEE8021.11n A-MSDU handler.
added function:
- ieee80211_data_to_8023: transfering 802.11 data frames to 802.3 frame
eliminated handlers:
- ieee80211_rx_h_drop_unencrypted: now function ieee80211_drop_unencrypted
- ieee80211_rx_h_802_1x_pae: now function ieee80211_802_1x_pae
changed handlers:
- ieee80211_rx_h_data: now contains calls to three above function
Signed-off-by: Ron Rindjunsky <[email protected]>
---
net/mac80211/ieee80211_i.h | 2 +-
net/mac80211/rx.c | 88 ++++++++++++++++++++++++++------------------
net/mac80211/tx.c | 12 +++--
net/mac80211/util.c | 14 +------
4 files changed, 61 insertions(+), 55 deletions(-)
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index b4e32ab..0444809 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -792,7 +792,7 @@ extern void *mac80211_wiphy_privid; /* for wiphy privid */
extern const unsigned char rfc1042_header[6];
extern const unsigned char bridge_tunnel_header[6];
u8 *ieee80211_get_bssid(struct ieee80211_hdr *hdr, size_t len);
-int ieee80211_is_eapol(const struct sk_buff *skb);
+int ieee80211_is_eapol(const struct sk_buff *skb, int hdrlen);
int ieee80211_frame_duration(struct ieee80211_local *local, size_t len,
int rate, int erp, int short_preamble);
void mac80211_ev_michael_mic_failure(struct net_device *dev, int keyidx,
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index 428a9fc..497c27c 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -956,68 +956,64 @@ ieee80211_rx_h_remove_qos_control(struct ieee80211_txrx_data *rx)
return TXRX_CONTINUE;
}
-static ieee80211_txrx_result
-ieee80211_rx_h_802_1x_pae(struct ieee80211_txrx_data *rx)
+static int
+ieee80211_drop_802_1x_pae(struct ieee80211_txrx_data *rx, int hdrlen)
{
- if (rx->sdata->eapol && ieee80211_is_eapol(rx->skb) &&
+ if (rx->sdata->eapol && ieee80211_is_eapol(rx->skb, hdrlen) &&
rx->sdata->type != IEEE80211_IF_TYPE_STA &&
(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
- return TXRX_CONTINUE;
+ return 0;
if (unlikely(rx->sdata->ieee802_1x &&
(rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
(rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_NULLFUNC &&
(!rx->sta || !(rx->sta->flags & WLAN_STA_AUTHORIZED)) &&
- !ieee80211_is_eapol(rx->skb))) {
+ !ieee80211_is_eapol(rx->skb, hdrlen))) {
#ifdef CONFIG_MAC80211_DEBUG
- struct ieee80211_hdr *hdr =
- (struct ieee80211_hdr *) rx->skb->data;
- DECLARE_MAC_BUF(mac);
- printk(KERN_DEBUG "%s: dropped frame from %s"
- " (unauthorized port)\n", rx->dev->name,
- print_mac(mac, hdr->addr2));
+ printk(KERN_DEBUG "%s: dropped frame "
+ "(unauthorized port)\n", rx->dev->name);
#endif /* CONFIG_MAC80211_DEBUG */
- return TXRX_DROP;
+ return -EACCES;
}
- return TXRX_CONTINUE;
+ return 0;
}
-static ieee80211_txrx_result
-ieee80211_rx_h_drop_unencrypted(struct ieee80211_txrx_data *rx)
+static int
+ieee80211_drop_unencrypted(struct ieee80211_txrx_data *rx, int hdrlen)
{
/*
* Pass through unencrypted frames if the hardware has
* decrypted them already.
*/
if (rx->u.rx.status->flag & RX_FLAG_DECRYPTED)
- return TXRX_CONTINUE;
+ return 0;
/* Drop unencrypted frames if key is set. */
if (unlikely(!(rx->fc & IEEE80211_FCTL_PROTECTED) &&
(rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
(rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_NULLFUNC &&
rx->sdata->drop_unencrypted &&
- (rx->sdata->eapol == 0 || !ieee80211_is_eapol(rx->skb)))) {
+ (!rx->sdata->eapol ||
+ !ieee80211_is_eapol(rx->skb, hdrlen)))) {
if (net_ratelimit())
printk(KERN_DEBUG "%s: RX non-WEP frame, but expected "
"encryption\n", rx->dev->name);
- return TXRX_DROP;
+ return -EACCES;
}
- return TXRX_CONTINUE;
+ return 0;
}
-static ieee80211_txrx_result
-ieee80211_rx_h_data(struct ieee80211_txrx_data *rx)
+static int
+ieee80211_data_to_8023(struct ieee80211_txrx_data *rx)
{
struct net_device *dev = rx->dev;
- struct ieee80211_local *local = rx->local;
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
u16 fc, hdrlen, ethertype;
u8 *payload;
u8 dst[ETH_ALEN];
u8 src[ETH_ALEN];
- struct sk_buff *skb = rx->skb, *skb2;
+ struct sk_buff *skb = rx->skb;
struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
DECLARE_MAC_BUF(mac);
DECLARE_MAC_BUF(mac2);
@@ -1025,11 +1021,9 @@ ieee80211_rx_h_data(struct ieee80211_txrx_data *rx)
DECLARE_MAC_BUF(mac4);
fc = rx->fc;
- if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA))
- return TXRX_CONTINUE;
if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
- return TXRX_DROP;
+ return -1;
hdrlen = ieee80211_get_hdrlen(fc);
@@ -1058,7 +1052,7 @@ ieee80211_rx_h_data(struct ieee80211_txrx_data *rx)
print_mac(mac, hdr->addr1),
print_mac(mac2, hdr->addr2),
print_mac(mac3, hdr->addr3));
- return TXRX_DROP;
+ return -1;
}
break;
case (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
@@ -1075,7 +1069,7 @@ ieee80211_rx_h_data(struct ieee80211_txrx_data *rx)
print_mac(mac2, hdr->addr2),
print_mac(mac3, hdr->addr3),
print_mac(mac4, hdr->addr4));
- return TXRX_DROP;
+ return -1;
}
break;
case IEEE80211_FCTL_FROMDS:
@@ -1086,7 +1080,7 @@ ieee80211_rx_h_data(struct ieee80211_txrx_data *rx)
if (sdata->type != IEEE80211_IF_TYPE_STA ||
(is_multicast_ether_addr(dst) &&
!compare_ether_addr(src, dev->dev_addr)))
- return TXRX_DROP;
+ return -1;
break;
case 0:
/* DA SA BSSID */
@@ -1102,21 +1096,20 @@ ieee80211_rx_h_data(struct ieee80211_txrx_data *rx)
print_mac(mac2, hdr->addr2),
print_mac(mac3, hdr->addr3));
}
- return TXRX_DROP;
+ return -1;
}
break;
}
- payload = skb->data + hdrlen;
-
if (unlikely(skb->len - hdrlen < 8)) {
if (net_ratelimit()) {
printk(KERN_DEBUG "%s: RX too short data frame "
"payload\n", dev->name);
}
- return TXRX_DROP;
+ return -1;
}
+ payload = skb->data + hdrlen;
ethertype = (payload[6] << 8) | payload[7];
if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
@@ -1137,8 +1130,33 @@ ieee80211_rx_h_data(struct ieee80211_txrx_data *rx)
memcpy(ehdr->h_source, src, ETH_ALEN);
ehdr->h_proto = len;
}
- skb->dev = dev;
+ return 0;
+}
+static ieee80211_txrx_result
+ieee80211_rx_h_data(struct ieee80211_txrx_data *rx)
+{
+ struct net_device *dev = rx->dev;
+ struct ieee80211_local *local = rx->local;
+ u16 fc;
+ int err;
+ struct sk_buff *skb, *skb2;
+ struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+
+ fc = rx->fc;
+ if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA))
+ return TXRX_CONTINUE;
+
+ err = ieee80211_data_to_8023(rx);
+ if (unlikely(err))
+ return TXRX_DROP;
+
+ if ((ieee80211_drop_802_1x_pae(rx, sizeof(struct ethhdr))) ||
+ (ieee80211_drop_unencrypted(rx, sizeof(struct ethhdr))))
+ return TXRX_DROP;
+
+ skb = rx->skb;
+ skb->dev = dev;
skb2 = NULL;
dev->stats.rx_packets++;
@@ -1341,8 +1359,6 @@ ieee80211_rx_handler ieee80211_rx_handlers[] =
* are not passed to user space by these functions
*/
ieee80211_rx_h_remove_qos_control,
- ieee80211_rx_h_802_1x_pae,
- ieee80211_rx_h_drop_unencrypted,
ieee80211_rx_h_data,
ieee80211_rx_h_mgmt,
NULL
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 1a53154..8b3f056 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -420,7 +420,6 @@ ieee80211_tx_h_unicast_ps_buf(struct ieee80211_txrx_data *tx)
return TXRX_CONTINUE;
}
-
static ieee80211_txrx_result
ieee80211_tx_h_ps_buf(struct ieee80211_txrx_data *tx)
{
@@ -433,13 +432,15 @@ ieee80211_tx_h_ps_buf(struct ieee80211_txrx_data *tx)
return ieee80211_tx_h_multicast_ps_buf(tx);
}
-
-
-
static ieee80211_txrx_result
ieee80211_tx_h_select_key(struct ieee80211_txrx_data *tx)
{
struct ieee80211_key *key;
+ const struct ieee80211_hdr *hdr;
+ u16 fc;
+
+ hdr = (const struct ieee80211_hdr *) tx->skb->data;
+ fc = le16_to_cpu(hdr->frame_control);
if (unlikely(tx->u.tx.control->flags & IEEE80211_TXCTL_DO_NOT_ENCRYPT))
tx->key = NULL;
@@ -448,7 +449,8 @@ ieee80211_tx_h_select_key(struct ieee80211_txrx_data *tx)
else if ((key = rcu_dereference(tx->sdata->default_key)))
tx->key = key;
else if (tx->sdata->drop_unencrypted &&
- !(tx->sdata->eapol && ieee80211_is_eapol(tx->skb))) {
+ !(tx->sdata->eapol &&
+ ieee80211_is_eapol(tx->skb, ieee80211_get_hdrlen(fc)))) {
I802_DEBUG_INC(tx->local->tx_handlers_drop_unencrypted);
return TXRX_DROP;
} else {
diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index 5a0564e..f90287a 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -217,23 +217,11 @@ int ieee80211_get_hdrlen_from_skb(const struct sk_buff *skb)
}
EXPORT_SYMBOL(ieee80211_get_hdrlen_from_skb);
-int ieee80211_is_eapol(const struct sk_buff *skb)
+int ieee80211_is_eapol(const struct sk_buff *skb, int hdrlen)
{
- const struct ieee80211_hdr *hdr;
- u16 fc;
- int hdrlen;
-
if (unlikely(skb->len < 10))
return 0;
- hdr = (const struct ieee80211_hdr *) skb->data;
- fc = le16_to_cpu(hdr->frame_control);
-
- if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
- return 0;
-
- hdrlen = ieee80211_get_hdrlen(fc);
-
if (unlikely(skb->len >= hdrlen + sizeof(eapol_header) &&
memcmp(skb->data + hdrlen, eapol_header,
sizeof(eapol_header)) == 0))
--
1.5.3.3
---------------------------------------------------------------------
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recipient, please contact the sender and delete all copies.
After seeing the corresponding a-msdu patch here are a few more
questions.
> +static ieee80211_txrx_result
> +ieee80211_rx_h_data(struct ieee80211_txrx_data *rx)
> +{
> + struct net_device *dev = rx->dev;
> + struct ieee80211_local *local = rx->local;
> + u16 fc;
> + int err;
> + struct sk_buff *skb, *skb2;
> + struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
> +
> + fc = rx->fc;
> + if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA))
> + return TXRX_CONTINUE;
> +
> + err = ieee80211_data_to_8023(rx);
> + if (unlikely(err))
> + return TXRX_DROP;
> +
> + if ((ieee80211_drop_802_1x_pae(rx, sizeof(struct ethhdr))) ||
> + (ieee80211_drop_unencrypted(rx, sizeof(struct ethhdr))))
> + return TXRX_DROP;
I like this.
> + skb = rx->skb;
> + skb->dev = dev;
> skb2 = NULL;
>
> dev->stats.rx_packets++;
Ok so the stuff that comes after this until the ned of the function is
responsible for delivering the packet. Maybe that should be split out
from the function too into something like ieee80211_deliver_skb()? In
the A-MSDU code you've had to basically copy all this code into the loop
as far as I can tell, something which I'd like to avoid very much.
johannes
Hi Ron,
Sorry this will most likely in email crossing because I'm writing this
as I haven't been able to check mail since yesterday afternoon.
Looking into the eapol handling in more detail, I found another bug with
your patch. Namely, in the RX path, you have:
> - if (rx->sdata->eapol && ieee80211_is_eapol(rx->skb) &&
> + if (rx->sdata->eapol && ieee80211_is_eapol(rx->skb, hdrlen) &&
at which point the frame is already reframed to 802.3.
However,
> -int ieee80211_is_eapol(const struct sk_buff *skb)
> +int ieee80211_is_eapol(const struct sk_buff *skb, int hdrlen)
> {
> if (unlikely(skb->len >= hdrlen + sizeof(eapol_header) &&
> memcmp(skb->data + hdrlen, eapol_header,
> sizeof(eapol_header)) == 0))
here checks the full 802.2 LLC header which was removed by the
reframing, thus this check will always be false.
I think we should, instead, have the ieee80211_data_to_8023 function set
skb->protocol correctly, and leave the skb's data pointer pointing to
the payload rather than the ethernet header, like eth_type_trans() would
do. In fact, I think we can just call it after we've reframed the frame.
Then, we can check skb->protocol for EAPOL which is a much cheaper check
too.
The thing I'm not entirely sure about is what happens with
eth_type_trans() and the pulling of the ethernet header. Wouldn't that
cause us problems with the skb->data[] accesses in
ieee80211_subif_start_xmit() once the frame arrives back there?
johannes
> > +static ieee80211_txrx_result
> > +ieee80211_rx_h_data(struct ieee80211_txrx_data *rx)
> > +{
> > + struct net_device *dev = rx->dev;
> > + struct ieee80211_local *local = rx->local;
> > + u16 fc;
> > + int err;
> > + struct sk_buff *skb, *skb2;
> > + struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
> > +
> > + fc = rx->fc;
> > + if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA))
> > + return TXRX_CONTINUE;
> > +
> > + err = ieee80211_data_to_8023(rx);
> > + if (unlikely(err))
> > + return TXRX_DROP;
> > +
> > + if ((ieee80211_drop_802_1x_pae(rx, sizeof(struct ethhdr))) ||
> > + (ieee80211_drop_unencrypted(rx, sizeof(struct ethhdr))))
> > + return TXRX_DROP;
>
> I like this.
>
> > + skb = rx->skb;
> > + skb->dev = dev;
> > skb2 = NULL;
> >
> > dev->stats.rx_packets++;
>
> Ok so the stuff that comes after this until the ned of the function is
> responsible for delivering the packet. Maybe that should be split out
> from the function too into something like ieee80211_deliver_skb()? In
> the A-MSDU code you've had to basically copy all this code into the loop
> as far as I can tell, something which I'd like to avoid very much.
I agree, it will be more readable that way. i'll do the needed changes.
>
> johannes
>
>