From eaf85ca7fecb218fc41ff57c1642ca73b097aabb Mon Sep 17 00:00:00 2001 From: Zhu Yi Date: Tue, 1 Dec 2009 10:18:37 +0800 Subject: wireless: add ieee80211_amsdu_to_8023s 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 Signed-off-by: Zhu Yi Signed-off-by: John W. Linville --- net/wireless/util.c | 99 +++++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 97 insertions(+), 2 deletions(-) (limited to 'net/wireless') diff --git a/net/wireless/util.c b/net/wireless/util.c index a3c841a..23557c1 100644 --- a/net/wireless/util.c +++ b/net/wireless/util.c @@ -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; @@ -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; @@ -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) { -- cgit v1.1