Skip to content

Commit

Permalink
wireless: add ieee80211_amsdu_to_8023s
Browse files Browse the repository at this point in the history 
Move the A-MSDU handling code from mac80211 to cfg80211 so that more
drivers can use it. The new created function ieee80211_amsdu_to_8023s
converts an A-MSDU frame to a list of 802.3 frames.

Cc: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
  • Loading branch information
Zhu Yi authored and John W. Linville committed Dec 22, 2009
1 parent ca99861 commit eaf85ca
Show file tree
Hide file tree
Showing 3 changed files with 137 additions and 90 deletions.
22 changes: 20 additions & 2 deletions include/net/cfg80211.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1578,7 +1578,7 @@ unsigned int ieee80211_hdrlen(__le16 fc);
* @addr: the device MAC address
* @iftype: the virtual interface type
*/
int ieee80211_data_to_8023(struct sk_buff *skb, u8 *addr,
int ieee80211_data_to_8023(struct sk_buff *skb, const u8 *addr,
enum nl80211_iftype iftype);

/**
Expand All @@ -1589,9 +1589,27 @@ int ieee80211_data_to_8023(struct sk_buff *skb, u8 *addr,
* @bssid: the network bssid (used only for iftype STATION and ADHOC)
* @qos: build 802.11 QoS data frame
*/
int ieee80211_data_from_8023(struct sk_buff *skb, u8 *addr,
int ieee80211_data_from_8023(struct sk_buff *skb, const u8 *addr,
enum nl80211_iftype iftype, u8 *bssid, bool qos);

/**
* ieee80211_amsdu_to_8023s - decode an IEEE 802.11n A-MSDU frame
*
* Decode an IEEE 802.11n A-MSDU frame and convert it to a list of
* 802.3 frames. The @list will be empty if the decode fails. The
* @skb is consumed after the function returns.
*
* @skb: The input IEEE 802.11n A-MSDU frame.
* @list: The output list of 802.3 frames. It must be allocated and
* initialized by by the caller.
* @addr: The device MAC address.
* @iftype: The device interface type.
* @extra_headroom: The hardware extra headroom for SKBs in the @list.
*/
void ieee80211_amsdu_to_8023s(struct sk_buff *skb, struct sk_buff_head *list,
const u8 *addr, enum nl80211_iftype iftype,
const unsigned int extra_headroom);

/**
* cfg80211_classify8021d - determine the 802.1p/1d tag for a data frame
* @skb: the data frame
Expand Down
106 changes: 20 additions & 86 deletions net/mac80211/rx.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1541,16 +1541,10 @@ static ieee80211_rx_result debug_noinline
ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
{
struct net_device *dev = rx->sdata->dev;
struct ieee80211_local *local = rx->local;
u16 ethertype;
u8 *payload;
struct sk_buff *skb = rx->skb, *frame = NULL;
struct sk_buff *skb = rx->skb;
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
__le16 fc = hdr->frame_control;
const struct ethhdr *eth;
int remaining, err;
u8 dst[ETH_ALEN];
u8 src[ETH_ALEN];
struct sk_buff_head frame_list;

if (unlikely(!ieee80211_is_data(fc)))
return RX_CONTINUE;
Expand All @@ -1561,94 +1555,34 @@ ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
if (!(rx->flags & IEEE80211_RX_AMSDU))
return RX_CONTINUE;

err = __ieee80211_data_to_8023(rx);
if (unlikely(err))
if (ieee80211_has_a4(hdr->frame_control) &&
rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
!rx->sdata->u.vlan.sta)
return RX_DROP_UNUSABLE;

skb->dev = dev;

dev->stats.rx_packets++;
dev->stats.rx_bytes += skb->len;

/* skip the wrapping header */
eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
if (!eth)
if (is_multicast_ether_addr(hdr->addr1) &&
((rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
rx->sdata->u.vlan.sta) ||
(rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
rx->sdata->u.mgd.use_4addr)))
return RX_DROP_UNUSABLE;

while (skb != frame) {
u8 padding;
__be16 len = eth->h_proto;
unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);

remaining = skb->len;
memcpy(dst, eth->h_dest, ETH_ALEN);
memcpy(src, eth->h_source, ETH_ALEN);
skb->dev = dev;
__skb_queue_head_init(&frame_list);

padding = ((4 - subframe_len) & 0x3);
/* the last MSDU has no padding */
if (subframe_len > remaining)
return RX_DROP_UNUSABLE;
ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr,
rx->sdata->vif.type,
rx->local->hw.extra_tx_headroom);

skb_pull(skb, sizeof(struct ethhdr));
/* if last subframe reuse skb */
if (remaining <= subframe_len + padding)
frame = skb;
else {
/*
* Allocate and reserve two bytes more for payload
* alignment since sizeof(struct ethhdr) is 14.
*/
frame = dev_alloc_skb(
ALIGN(local->hw.extra_tx_headroom, 4) +
subframe_len + 2);

if (frame == NULL)
return RX_DROP_UNUSABLE;

skb_reserve(frame,
ALIGN(local->hw.extra_tx_headroom, 4) +
sizeof(struct ethhdr) + 2);
memcpy(skb_put(frame, ntohs(len)), skb->data,
ntohs(len));

eth = (struct ethhdr *) skb_pull(skb, ntohs(len) +
padding);
if (!eth) {
dev_kfree_skb(frame);
return RX_DROP_UNUSABLE;
}
}

skb_reset_network_header(frame);
frame->dev = dev;
frame->priority = skb->priority;
rx->skb = frame;

payload = frame->data;
ethertype = (payload[6] << 8) | payload[7];

if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
compare_ether_addr(payload,
bridge_tunnel_header) == 0)) {
/* remove RFC1042 or Bridge-Tunnel
* encapsulation and replace EtherType */
skb_pull(frame, 6);
memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
} else {
memcpy(skb_push(frame, sizeof(__be16)),
&len, sizeof(__be16));
memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
}
while (!skb_queue_empty(&frame_list)) {
rx->skb = __skb_dequeue(&frame_list);

if (!ieee80211_frame_allowed(rx, fc)) {
if (skb == frame) /* last frame */
return RX_DROP_UNUSABLE;
dev_kfree_skb(frame);
dev_kfree_skb(rx->skb);
continue;
}
dev->stats.rx_packets++;
dev->stats.rx_bytes += rx->skb->len;

ieee80211_deliver_skb(rx);
}
Expand Down
99 changes: 97 additions & 2 deletions net/wireless/util.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -285,7 +285,7 @@ static int ieee80211_get_mesh_hdrlen(struct ieee80211s_hdr *meshhdr)
}
}

int ieee80211_data_to_8023(struct sk_buff *skb, u8 *addr,
int ieee80211_data_to_8023(struct sk_buff *skb, const u8 *addr,
enum nl80211_iftype iftype)
{
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
Expand Down Expand Up @@ -383,7 +383,7 @@ int ieee80211_data_to_8023(struct sk_buff *skb, u8 *addr,
}
EXPORT_SYMBOL(ieee80211_data_to_8023);

int ieee80211_data_from_8023(struct sk_buff *skb, u8 *addr,
int ieee80211_data_from_8023(struct sk_buff *skb, const u8 *addr,
enum nl80211_iftype iftype, u8 *bssid, bool qos)
{
struct ieee80211_hdr hdr;
Expand Down Expand Up @@ -497,6 +497,101 @@ int ieee80211_data_from_8023(struct sk_buff *skb, u8 *addr,
}
EXPORT_SYMBOL(ieee80211_data_from_8023);


void ieee80211_amsdu_to_8023s(struct sk_buff *skb, struct sk_buff_head *list,
const u8 *addr, enum nl80211_iftype iftype,
const unsigned int extra_headroom)
{
struct sk_buff *frame = NULL;
u16 ethertype;
u8 *payload;
const struct ethhdr *eth;
int remaining, err;
u8 dst[ETH_ALEN], src[ETH_ALEN];

err = ieee80211_data_to_8023(skb, addr, iftype);
if (err)
goto out;

/* skip the wrapping header */
eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
if (!eth)
goto out;

while (skb != frame) {
u8 padding;
__be16 len = eth->h_proto;
unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);

remaining = skb->len;
memcpy(dst, eth->h_dest, ETH_ALEN);
memcpy(src, eth->h_source, ETH_ALEN);

padding = (4 - subframe_len) & 0x3;
/* the last MSDU has no padding */
if (subframe_len > remaining)
goto purge;

skb_pull(skb, sizeof(struct ethhdr));
/* reuse skb for the last subframe */
if (remaining <= subframe_len + padding)
frame = skb;
else {
unsigned int hlen = ALIGN(extra_headroom, 4);
/*
* Allocate and reserve two bytes more for payload
* alignment since sizeof(struct ethhdr) is 14.
*/
frame = dev_alloc_skb(hlen + subframe_len + 2);
if (!frame)
goto purge;

skb_reserve(frame, hlen + sizeof(struct ethhdr) + 2);
memcpy(skb_put(frame, ntohs(len)), skb->data,
ntohs(len));

eth = (struct ethhdr *)skb_pull(skb, ntohs(len) +
padding);
if (!eth) {
dev_kfree_skb(frame);
goto purge;
}
}

skb_reset_network_header(frame);
frame->dev = skb->dev;
frame->priority = skb->priority;

payload = frame->data;
ethertype = (payload[6] << 8) | payload[7];

if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
compare_ether_addr(payload,
bridge_tunnel_header) == 0)) {
/* remove RFC1042 or Bridge-Tunnel
* encapsulation and replace EtherType */
skb_pull(frame, 6);
memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
} else {
memcpy(skb_push(frame, sizeof(__be16)), &len,
sizeof(__be16));
memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
}
__skb_queue_tail(list, frame);
}

return;

purge:
__skb_queue_purge(list);
out:
dev_kfree_skb(skb);
}
EXPORT_SYMBOL(ieee80211_amsdu_to_8023s);

/* Given a data frame determine the 802.1p/1d tag to use. */
unsigned int cfg80211_classify8021d(struct sk_buff *skb)
{
Expand Down

0 comments on commit eaf85ca

Please sign in to comment.