static struct sk_buff *vlan_reorder_header(struct sk_buff *skb)
{
	if (skb_cow(skb, skb_headroom(skb)) < 0)
		return NULL;
	memmove(skb->data - ETH_HLEN, skb->data - VLAN_ETH_HLEN, 2 * ETH_ALEN);
	skb->mac_header += VLAN_HLEN;
	skb_reset_mac_len(skb);
	return skb;
}

static int mt7601u_skb_rooms(struct mt7601u_dev *dev, struct sk_buff *skb)
{
	int hdr_len = ieee80211_get_hdrlen_from_skb(skb);
	u32 need_head;

	need_head = sizeof(struct mt76_txwi) + 4;
	if (hdr_len % 4)
		need_head += 2;

	return skb_cow(skb, need_head);
}

static inline int ip_rcv_options(struct sk_buff *skb)
{
	struct ip_options *opt;
	struct iphdr *iph;
	struct net_device *dev = skb->dev;

	/* It looks as overkill, because not all
	   IP options require packet mangling.
	   But it is the easiest for now, especially taking
	   into account that combination of IP options
	   and running sniffer is extremely rare condition.
					      --ANK (980813)
	*/
	if (skb_cow(skb, skb_headroom(skb))) {
		IP_INC_STATS_BH(dev_net(dev), IPSTATS_MIB_INDISCARDS);
		goto drop;
	}

	iph = ip_hdr(skb);
	opt = &(IPCB(skb)->opt);
	opt->optlen = iph->ihl*4 - sizeof(struct iphdr);

	if (ip_options_compile(dev_net(dev), opt, skb)) {
		IP_INC_STATS_BH(dev_net(dev), IPSTATS_MIB_INHDRERRORS);
		goto drop;
	}

	if (unlikely(opt->srr)) {
		struct in_device *in_dev = in_dev_get(dev);
		if (in_dev) {
			if (!IN_DEV_SOURCE_ROUTE(in_dev)) {
				if (IN_DEV_LOG_MARTIANS(in_dev) &&
				    net_ratelimit())
					printk(KERN_INFO "source route option "
					       NIPQUAD_FMT " -> " NIPQUAD_FMT "\n",
					       NIPQUAD(iph->saddr),
					       NIPQUAD(iph->daddr));
				in_dev_put(in_dev);
				goto drop;
			}

			in_dev_put(in_dev);
		}

		if (ip_options_rcv_srr(skb))
			goto drop;
	}

	return 0;
drop:
	return -1;
}

/*
 * When forwarding bridge frames, we save a copy of the original
 * header before processing.
 */
int nf_bridge_copy_header(struct sk_buff *skb)
{
	int err;
	int header_size = ETH_HLEN + nf_bridge_encap_header_len(skb);

	err = skb_cow(skb, header_size);
	if (err)
		return err;

	skb_copy_to_linear_data_offset(skb, -header_size,
				       skb->nf_bridge->data, header_size);
	__skb_push(skb, nf_bridge_encap_header_len(skb));
	return 0;
}

static inline struct sk_buff *mapi_ip_rcv_finish(struct sk_buff *skb,struct predef_func *pf)
{
	struct iphdr *iph = skb->nh.iph;
	struct cook_ip_struct *cis = (struct cook_ip_struct *)pf->data;

	if(iph->ihl > 5)
	{
		/*
		 * It looks as overkill, because not all
		 * IP options require packet mangling.
		 * But it is the easiest for now, especially taking
		 * into account that combination of IP options
		 * and running sniffer is extremely rare condition.
		 * --ANK (980813)
		 */

		if(skb_cow(skb,skb_headroom(skb)))
		{
			goto drop;
		}

		iph = skb->nh.iph;

		skb->ip_summed = 0;

		if(ip_options_compile(NULL,skb))
		{
			goto inhdr_error;
		}
	}

	return mapi_ip_local_deliver(skb,pf);

inhdr_error:
	spin_lock(&pf->data_lock);
	cis->ip_options_errors++;
	spin_unlock(&pf->data_lock);
	
	MAPI_DEBUG(if(net_ratelimit()) 
		   printk("COOK_IP : IP options error : %u.%u.%u.%u <- %u.%u.%u.%u\n",
			   NIPQUAD(skb->nh.iph->daddr),
			   NIPQUAD(skb->nh.iph->saddr)));

drop:
	
	kfree_skb(skb);

	return NULL;
}

static inline struct sk_buff *vlan_check_reorder_header(struct sk_buff *skb)
{
	if (vlan_dev_info(skb->dev)->flags & VLAN_FLAG_REORDER_HDR) {
		if (skb_cow(skb, skb_headroom(skb)) < 0)
			skb = NULL;
		if (skb) {
			/* Lifted from Gleb's VLAN code... */
			memmove(skb->data - ETH_HLEN,
				skb->data - VLAN_ETH_HLEN, 12);
			skb->mac_header += VLAN_HLEN;
		}
	}

	return skb;
}

static int x25_data_indication(struct net_device *dev, struct sk_buff *skb)
{
	unsigned char *ptr;

	skb_push(skb, 1);

	if (skb_cow(skb, 1))
		return NET_RX_DROP;

	ptr  = skb->data;
	*ptr = X25_IFACE_DATA;

	skb->protocol = x25_type_trans(skb, dev);
	return netif_rx(skb);
}

/*
 * When forwarding bridge frames, we save a copy of the original
 * header before processing.
 */
int nf_bridge_copy_header(struct sk_buff *skb)
{
	int err;
        int header_size = ETH_HLEN;

	if (skb->protocol == htons(ETH_P_8021Q))
		header_size += VLAN_HLEN;

	err = skb_cow(skb, header_size);
	if (err)
		return err;

	memcpy(skb->data - header_size, skb->nf_bridge->data, header_size);

	if (skb->protocol == htons(ETH_P_8021Q))
		__skb_push(skb, VLAN_HLEN);
	return 0;
}

int mt76_insert_hdr_pad(struct sk_buff *skb)
{
    int len = ieee80211_get_hdrlen_from_skb(skb);
    int ret;

    if (len % 4 == 0)
        return 0;

    ret = skb_cow(skb, 2);
    if (ret)
        return ret;

    skb_push(skb, 2);
    memmove(skb->data, skb->data + 2, len);

    skb->data[len] = 0;
    skb->data[len + 1] = 0;
    return 0;
}

static int comxlapb_data_indication(void *token, struct sk_buff *skb)
{
	struct comx_channel *ch = token; 

	if (ch->dev->type == ARPHRD_X25) {
		skb_push(skb, 1);

		if (skb_cow(skb, 1))
			return NET_RX_DROP;

		skb->data[0] = 0;	// indicate data for X25
		skb->protocol = htons(ETH_P_X25);
	} else {
		skb->protocol = htons(ETH_P_IP);
	}

	skb->dev = ch->dev;
	skb->mac.raw = skb->data;
	return comx_rx(ch->dev, skb);
}

//.........这里部分代码省略.........
	}

	/* XXX: idev->cnf.proxy_ndp? */
	if (net->ipv6.devconf_all->proxy_ndp &&
	    pneigh_lookup(&nd_tbl, net, &hdr->daddr, skb->dev, 0)) {
		int proxied = ip6_forward_proxy_check(skb);
		if (proxied > 0)
			return ip6_input(skb);
		else if (proxied < 0) {
			IP6_INC_STATS(net, ip6_dst_idev(dst),
				      IPSTATS_MIB_INDISCARDS);
			goto drop;
		}
	}

	if (!xfrm6_route_forward(skb)) {
		IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_INDISCARDS);
		goto drop;
	}
	dst = skb_dst(skb);

	/* IPv6 specs say nothing about it, but it is clear that we cannot
	   send redirects to source routed frames.
	   We don't send redirects to frames decapsulated from IPsec.
	 */
	n = dst_get_neighbour(dst);
	if (skb->dev == dst->dev && n && opt->srcrt == 0 && !skb_sec_path(skb)) {
		struct in6_addr *target = NULL;
		struct rt6_info *rt;

		/*
		 *	incoming and outgoing devices are the same
		 *	send a redirect.
		 */

		rt = (struct rt6_info *) dst;
		if ((rt->rt6i_flags & RTF_GATEWAY))
			target = (struct in6_addr*)&n->primary_key;
		else
			target = &hdr->daddr;

		if (!rt->rt6i_peer)
			rt6_bind_peer(rt, 1);

		/* Limit redirects both by destination (here)
		   and by source (inside ndisc_send_redirect)
		 */
		if (inet_peer_xrlim_allow(rt->rt6i_peer, 1*HZ))
			ndisc_send_redirect(skb, n, target);
	} else {
		int addrtype = ipv6_addr_type(&hdr->saddr);

		/* This check is security critical. */
		if (addrtype == IPV6_ADDR_ANY ||
		    addrtype & (IPV6_ADDR_MULTICAST | IPV6_ADDR_LOOPBACK))
			goto error;
		if (addrtype & IPV6_ADDR_LINKLOCAL) {
			icmpv6_send(skb, ICMPV6_DEST_UNREACH,
				    ICMPV6_NOT_NEIGHBOUR, 0);
			goto error;
		}
	}

	mtu = dst_mtu(dst);
	if (mtu < IPV6_MIN_MTU)
		mtu = IPV6_MIN_MTU;

	if (skb->len > mtu && !skb_is_gso(skb)) {
		/* Again, force OUTPUT device used as source address */
		skb->dev = dst->dev;
		icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
		IP6_INC_STATS_BH(net,
				 ip6_dst_idev(dst), IPSTATS_MIB_INTOOBIGERRORS);
		IP6_INC_STATS_BH(net,
				 ip6_dst_idev(dst), IPSTATS_MIB_FRAGFAILS);
		kfree_skb(skb);
		return -EMSGSIZE;
	}

	if (skb_cow(skb, dst->dev->hard_header_len)) {
		IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTDISCARDS);
		goto drop;
	}

	hdr = ipv6_hdr(skb);

	/* Mangling hops number delayed to point after skb COW */

	hdr->hop_limit--;

	IP6_INC_STATS_BH(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTFORWDATAGRAMS);
	return NF_HOOK(NFPROTO_IPV6, NF_INET_FORWARD, skb, skb->dev, dst->dev,
		       ip6_forward_finish);

error:
	IP6_INC_STATS_BH(net, ip6_dst_idev(dst), IPSTATS_MIB_INADDRERRORS);
drop:
	kfree_skb(skb);
	return -EINVAL;
}

static int udp_uncompress(struct sk_buff *skb, size_t needed)
{
	u8 tmp = 0, val = 0;
	struct udphdr uh;
	bool fail;
	int err;

	fail = lowpan_fetch_skb(skb, &tmp, sizeof(tmp));

	pr_debug("UDP header uncompression\n");
	switch (tmp & LOWPAN_NHC_UDP_CS_P_11) {
	case LOWPAN_NHC_UDP_CS_P_00:
		fail |= lowpan_fetch_skb(skb, &uh.source, sizeof(uh.source));
		fail |= lowpan_fetch_skb(skb, &uh.dest, sizeof(uh.dest));
		break;
	case LOWPAN_NHC_UDP_CS_P_01:
		fail |= lowpan_fetch_skb(skb, &uh.source, sizeof(uh.source));
		fail |= lowpan_fetch_skb(skb, &val, sizeof(val));
		uh.dest = htons(val + LOWPAN_NHC_UDP_8BIT_PORT);
		break;
	case LOWPAN_NHC_UDP_CS_P_10:
		fail |= lowpan_fetch_skb(skb, &val, sizeof(val));
		uh.source = htons(val + LOWPAN_NHC_UDP_8BIT_PORT);
		fail |= lowpan_fetch_skb(skb, &uh.dest, sizeof(uh.dest));
		break;
	case LOWPAN_NHC_UDP_CS_P_11:
		fail |= lowpan_fetch_skb(skb, &val, sizeof(val));
		uh.source = htons(LOWPAN_NHC_UDP_4BIT_PORT + (val >> 4));
		uh.dest = htons(LOWPAN_NHC_UDP_4BIT_PORT + (val & 0x0f));
		break;
	default:
		BUG();
	}

	pr_debug("uncompressed UDP ports: src = %d, dst = %d\n",
		 ntohs(uh.source), ntohs(uh.dest));

	/* checksum */
	if (tmp & LOWPAN_NHC_UDP_CS_C) {
		pr_debug_ratelimited("checksum elided currently not supported\n");
		fail = true;
	} else {
		fail |= lowpan_fetch_skb(skb, &uh.check, sizeof(uh.check));
	}

	if (fail)
		return -EINVAL;

	/* UDP length needs to be infered from the lower layers
	 * here, we obtain the hint from the remaining size of the
	 * frame
	 */
	switch (lowpan_priv(skb->dev)->lltype) {
	case LOWPAN_LLTYPE_IEEE802154:
		if (lowpan_802154_cb(skb)->d_size)
			uh.len = htons(lowpan_802154_cb(skb)->d_size -
				       sizeof(struct ipv6hdr));
		else
			uh.len = htons(skb->len + sizeof(struct udphdr));
		break;
	default:
		uh.len = htons(skb->len + sizeof(struct udphdr));
		break;
	}
	pr_debug("uncompressed UDP length: src = %d", ntohs(uh.len));

	/* replace the compressed UDP head by the uncompressed UDP
	 * header
	 */
	err = skb_cow(skb, needed);
	if (unlikely(err))
		return err;

	skb_push(skb, sizeof(struct udphdr));
	skb_copy_to_linear_data(skb, &uh, sizeof(struct udphdr));

	return 0;
}

static int mpls_forward(struct sk_buff *skb, struct net_device *dev,
			struct packet_type *pt, struct net_device *orig_dev)
{
	struct net *net = dev_net(dev);
	struct mpls_shim_hdr *hdr;
	struct mpls_route *rt;
	struct mpls_entry_decoded dec;
	struct net_device *out_dev;
	struct mpls_dev *mdev;
	unsigned int hh_len;
	unsigned int new_header_size;
	unsigned int mtu;
	int err;

	/* Careful this entire function runs inside of an rcu critical section */

	mdev = mpls_dev_get(dev);
	if (!mdev || !mdev->input_enabled)
		goto drop;

	if (skb->pkt_type != PACKET_HOST)
		goto drop;

	if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
		goto drop;

	if (!pskb_may_pull(skb, sizeof(*hdr)))
		goto drop;

	/* Read and decode the label */
	hdr = mpls_hdr(skb);
	dec = mpls_entry_decode(hdr);

	/* Pop the label */
	skb_pull(skb, sizeof(*hdr));
	skb_reset_network_header(skb);

	skb_orphan(skb);

	rt = mpls_route_input_rcu(net, dec.label);
	if (!rt)
		goto drop;

	/* Find the output device */
	out_dev = rcu_dereference(rt->rt_dev);
	if (!mpls_output_possible(out_dev))
		goto drop;

	if (skb_warn_if_lro(skb))
		goto drop;

	skb_forward_csum(skb);

	/* Verify ttl is valid */
	if (dec.ttl <= 1)
		goto drop;
	dec.ttl -= 1;

	/* Verify the destination can hold the packet */
	new_header_size = mpls_rt_header_size(rt);
	mtu = mpls_dev_mtu(out_dev);
	if (mpls_pkt_too_big(skb, mtu - new_header_size))
		goto drop;

	hh_len = LL_RESERVED_SPACE(out_dev);
	if (!out_dev->header_ops)
		hh_len = 0;

	/* Ensure there is enough space for the headers in the skb */
	if (skb_cow(skb, hh_len + new_header_size))
		goto drop;

	skb->dev = out_dev;
	skb->protocol = htons(ETH_P_MPLS_UC);

	if (unlikely(!new_header_size && dec.bos)) {
		/* Penultimate hop popping */
		if (!mpls_egress(rt, skb, dec))
			goto drop;
	} else {
		bool bos;
		int i;
		skb_push(skb, new_header_size);
		skb_reset_network_header(skb);
		/* Push the new labels */
		hdr = mpls_hdr(skb);
		bos = dec.bos;
		for (i = rt->rt_labels - 1; i >= 0; i--) {
			hdr[i] = mpls_entry_encode(rt->rt_label[i], dec.ttl, 0, bos);
			bos = false;
		}
	}

	err = neigh_xmit(rt->rt_via_table, out_dev, rt->rt_via, skb);
	if (err)
		net_dbg_ratelimited("%s: packet transmission failed: %d\n",
				    __func__, err);
	return 0;

drop:
//.........这里部分代码省略.........

int ip_forward(struct sk_buff *skb)
{
	struct iphdr *iph;	/* Our header */
	struct rtable *rt;	/* Route we use */
	struct ip_options * opt	= &(IPCB(skb)->opt);

	if (skb_warn_if_lro(skb))
		goto drop;

	if (!xfrm4_policy_check(NULL, XFRM_POLICY_FWD, skb))
		goto drop;

	if (IPCB(skb)->opt.router_alert && ip_call_ra_chain(skb))
		return NET_RX_SUCCESS;

	if (skb->pkt_type != PACKET_HOST)
		goto drop;

	skb_forward_csum(skb);

	/*
	 *	According to the RFC, we must first decrease the TTL field. If
	 *	that reaches zero, we must reply an ICMP control message telling
	 *	that the packet's lifetime expired.
	 */
	if (ip_hdr(skb)->ttl <= 1)
		goto too_many_hops;

	if (!xfrm4_route_forward(skb))
		goto drop;

	rt = skb_rtable(skb);

	if (opt->is_strictroute && rt->rt_dst != rt->rt_gateway)
		goto sr_failed;

	if (unlikely(skb->len > dst_mtu(&rt->u.dst) && !skb_is_gso(skb) &&
		     (ip_hdr(skb)->frag_off & htons(IP_DF))) && !skb->local_df) {
		IP_INC_STATS(dev_net(rt->u.dst.dev), IPSTATS_MIB_FRAGFAILS);
		icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
			  htonl(dst_mtu(&rt->u.dst)));
		goto drop;
	}

	/* We are about to mangle packet. Copy it! */
	if (skb_cow(skb, LL_RESERVED_SPACE(rt->u.dst.dev)+rt->u.dst.header_len))
		goto drop;
	iph = ip_hdr(skb);

	/* Decrease ttl after skb cow done */
	ip_decrease_ttl(iph);

	/*
	 *	We now generate an ICMP HOST REDIRECT giving the route
	 *	we calculated.
	 */
	if (rt->rt_flags&RTCF_DOREDIRECT && !opt->srr && !skb_sec_path(skb))
		ip_rt_send_redirect(skb);

	skb->priority = rt_tos2priority(iph->tos);

	return NF_HOOK(PF_INET, NF_INET_FORWARD, skb, skb->dev, rt->u.dst.dev,
		       ip_forward_finish);

sr_failed:
	/*
	 *	Strict routing permits no gatewaying
	 */
	 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_SR_FAILED, 0);
	 goto drop;

too_many_hops:
	/* Tell the sender its packet died... */
	IP_INC_STATS_BH(dev_net(skb_dst(skb)->dev), IPSTATS_MIB_INHDRERRORS);
	icmp_send(skb, ICMP_TIME_EXCEEDED, ICMP_EXC_TTL, 0);
drop:
	kfree_skb(skb);
	return NET_RX_DROP;
}

INT SetupNextSend(PMINI_ADAPTER Adapter,  struct sk_buff *Packet, USHORT Vcid)
{
	int		status=0;
	BOOLEAN bHeaderSupressionEnabled = FALSE;
	B_UINT16            uiClassifierRuleID;
	u16	QueueIndex = skb_get_queue_mapping(Packet);
	LEADER Leader={0};

	if(Packet->len > MAX_DEVICE_DESC_SIZE)
	{
		status = STATUS_FAILURE;
		goto errExit;
	}

	
	uiClassifierRuleID = *((UINT32*) (Packet->cb)+SKB_CB_CLASSIFICATION_OFFSET);

	bHeaderSupressionEnabled = Adapter->PackInfo[QueueIndex].bHeaderSuppressionEnabled
		& Adapter->bPHSEnabled;

	if(Adapter->device_removed)
		{
		status = STATUS_FAILURE;
		goto errExit;
		}

	status = PHSTransmit(Adapter, &Packet, Vcid, uiClassifierRuleID, bHeaderSupressionEnabled,
							(UINT *)&Packet->len, Adapter->PackInfo[QueueIndex].bEthCSSupport);

	if(status != STATUS_SUCCESS)
	{
		BCM_DEBUG_PRINT(Adapter,DBG_TYPE_TX, NEXT_SEND, DBG_LVL_ALL, "PHS Transmit failed..\n");
		goto errExit;
	}

	Leader.Vcid	= Vcid;

	if(TCP_ACK == *((UINT32*) (Packet->cb) + SKB_CB_TCPACK_OFFSET ))
		Leader.Status = LEADER_STATUS_TCP_ACK;
	else
		Leader.Status = LEADER_STATUS;

	if(Adapter->PackInfo[QueueIndex].bEthCSSupport)
	{
		Leader.PLength = Packet->len;
		if(skb_headroom(Packet) < LEADER_SIZE)
        {
			if((status = skb_cow(Packet,LEADER_SIZE)))
			{
				BCM_DEBUG_PRINT(Adapter,DBG_TYPE_TX, NEXT_SEND, DBG_LVL_ALL,"bcm_transmit : Failed To Increase headRoom\n");
				goto errExit;
			}
		}
		skb_push(Packet, LEADER_SIZE);
		memcpy(Packet->data, &Leader, LEADER_SIZE);
	}
	else
	{
		Leader.PLength = Packet->len - ETH_HLEN;
		memcpy((LEADER*)skb_pull(Packet, (ETH_HLEN - LEADER_SIZE)), &Leader, LEADER_SIZE);
	}

	status = Adapter->interface_transmit(Adapter->pvInterfaceAdapter,
			Packet->data, (Leader.PLength + LEADER_SIZE));
	if(status)
	{
		++Adapter->dev->stats.tx_errors;
		if (netif_msg_tx_err(Adapter))
			pr_info(PFX "%s: transmit error %d\n", Adapter->dev->name,
				status);
	}
	else
	{
		struct net_device_stats *netstats = &Adapter->dev->stats;
		Adapter->PackInfo[QueueIndex].uiTotalTxBytes += Leader.PLength;

		netstats->tx_bytes += Leader.PLength;
		++netstats->tx_packets;

		Adapter->PackInfo[QueueIndex].uiCurrentTokenCount -= Leader.PLength << 3;
		Adapter->PackInfo[QueueIndex].uiSentBytes += (Packet->len);
		Adapter->PackInfo[QueueIndex].uiSentPackets++;
		Adapter->PackInfo[QueueIndex].NumOfPacketsSent++;

		atomic_dec(&Adapter->PackInfo[QueueIndex].uiPerSFTxResourceCount);
		Adapter->PackInfo[QueueIndex].uiThisPeriodSentBytes += Leader.PLength;
	}

	atomic_dec(&Adapter->CurrNumFreeTxDesc);

errExit:

	dev_kfree_skb(Packet);
	return status;
}

int PHSReceive(struct bcm_mini_adapter *Adapter,
					USHORT usVcid,
					struct sk_buff *packet,
					UINT *punPacketLen,
					UCHAR *pucEthernetHdr,
					UINT	bHeaderSuppressionEnabled)
{
	u32   nStandardPktHdrLen            		= 0;
	u32   nTotalsuppressedPktHdrBytes  = 0;
	int     ulPhsStatus 		= 0;
	PUCHAR pucInBuff = NULL ;
	UINT TotalBytesAdded = 0;
	if(!bHeaderSuppressionEnabled)
	{
		BCM_DEBUG_PRINT(Adapter,DBG_TYPE_OTHERS, PHS_RECEIVE,DBG_LVL_ALL,"\nPhs Disabled for incoming packet");
		return ulPhsStatus;
	}

	pucInBuff = packet->data;

	//Restore  PHS suppressed header
	nStandardPktHdrLen = packet->len;
	ulPhsStatus = PhsDeCompress(&Adapter->stBCMPhsContext,
		usVcid,
		pucInBuff,
		Adapter->ucaPHSPktRestoreBuf,
		&nTotalsuppressedPktHdrBytes,
		&nStandardPktHdrLen);

	BCM_DEBUG_PRINT(Adapter,DBG_TYPE_OTHERS, PHS_RECEIVE,DBG_LVL_ALL,"\nSuppressed PktHdrLen : 0x%x Restored PktHdrLen : 0x%x",
					nTotalsuppressedPktHdrBytes,nStandardPktHdrLen);

	if(ulPhsStatus != STATUS_PHS_COMPRESSED)
	{
		skb_pull(packet, 1);
		return STATUS_SUCCESS;
	}
	else
	{
		TotalBytesAdded = nStandardPktHdrLen - nTotalsuppressedPktHdrBytes - PHSI_LEN;
		if(TotalBytesAdded)
		{
			if(skb_headroom(packet) >= (SKB_RESERVE_ETHERNET_HEADER + TotalBytesAdded))
				skb_push(packet, TotalBytesAdded);
			else
			{
				if(skb_cow(packet, skb_headroom(packet) + TotalBytesAdded))
				{
					BCM_DEBUG_PRINT(Adapter,DBG_TYPE_PRINTK, 0, 0, "cow failed in receive\n");
					return STATUS_FAILURE;
				}

				skb_push(packet, TotalBytesAdded);
			}
		}

		memcpy(packet->data, Adapter->ucaPHSPktRestoreBuf, nStandardPktHdrLen);
	}

	return STATUS_SUCCESS;
}

//.........这里部分代码省略.........
	pucPHSPktHdrInBuf = Packet->data + BytesToRemove;
	//considering data after ethernet header
	if((*PacketLen - BytesToRemove) < MAX_PHS_LENGTHS)
	{

		unPHSPktHdrBytesCopied = (*PacketLen - BytesToRemove);
	}
	else
	{
		unPHSPktHdrBytesCopied = MAX_PHS_LENGTHS;
	}

	if( (unPHSPktHdrBytesCopied > 0 ) &&
		(unPHSPktHdrBytesCopied <= MAX_PHS_LENGTHS))
	{


		// Step 2 Suppress Header using PHS and fill into intermediate ucaPHSPktHdrOutBuf.
	// Suppress only if IP Header and PHS Enabled For the Service Flow
		if(((usPacketType == ETHERNET_FRAMETYPE_IPV4) ||
			(usPacketType == ETHERNET_FRAMETYPE_IPV6)) &&
			(bHeaderSuppressionEnabled))
		{
				BCM_DEBUG_PRINT(Adapter,DBG_TYPE_OTHERS, PHS_SEND, DBG_LVL_ALL,"\nTrying to PHS Compress Using Classifier rule 0x%X",uiClassifierRuleID);


				unPHSNewPktHeaderLen = unPHSPktHdrBytesCopied;
				ulPhsStatus = PhsCompress(&Adapter->stBCMPhsContext,
					Vcid,
					uiClassifierRuleID,
					pucPHSPktHdrInBuf,
					pucPHSPktHdrOutBuf,
					&unPhsOldHdrSize,
					&unPHSNewPktHeaderLen);
				BCM_DEBUG_PRINT(Adapter,DBG_TYPE_OTHERS, PHS_SEND, DBG_LVL_ALL,"\nPHS Old header Size : %d New Header Size  %d\n",unPhsOldHdrSize,unPHSNewPktHeaderLen);

				if(unPHSNewPktHeaderLen == unPhsOldHdrSize)
				{
					if(  ulPhsStatus == STATUS_PHS_COMPRESSED)
							bPHSI = *pucPHSPktHdrOutBuf;
					ulPhsStatus = STATUS_PHS_NOCOMPRESSION;
				}

				if(  ulPhsStatus == STATUS_PHS_COMPRESSED)
				{
					BCM_DEBUG_PRINT(Adapter,DBG_TYPE_OTHERS, PHS_SEND, DBG_LVL_ALL,"PHS Sending packet Compressed");

					if(skb_cloned(Packet))
					{
						newPacket = skb_copy(Packet, GFP_ATOMIC);

						if(newPacket == NULL)
							return STATUS_FAILURE;

						dev_kfree_skb(Packet);
						*pPacket = Packet = newPacket;
						pucPHSPktHdrInBuf = Packet->data  + BytesToRemove;
					}

					numBytesCompressed = unPhsOldHdrSize - (unPHSNewPktHeaderLen+PHSI_LEN);

					memcpy(pucPHSPktHdrInBuf + numBytesCompressed, pucPHSPktHdrOutBuf, unPHSNewPktHeaderLen + PHSI_LEN);
					memcpy(Packet->data + numBytesCompressed, Packet->data, BytesToRemove);
					skb_pull(Packet, numBytesCompressed);

					return STATUS_SUCCESS;
				}

				else
				{
					//if one byte headroom is not available, increase it through skb_cow
					if(!(skb_headroom(Packet) > 0))
					{
						if(skb_cow(Packet, 1))
						{
							BCM_DEBUG_PRINT(Adapter,DBG_TYPE_PRINTK, 0, 0, "SKB Cow Failed\n");
							return STATUS_FAILURE;
						}
					}
					skb_push(Packet, 1);

					// CAUTION: The MAC Header is getting corrupted here for IP CS - can be saved by copying 14 Bytes.  not needed .... hence corrupting it.
					*(Packet->data + BytesToRemove) = bPHSI;
					return STATUS_SUCCESS;
			}
		}
		else
		{
			if(!bHeaderSuppressionEnabled)
			{
				BCM_DEBUG_PRINT(Adapter,DBG_TYPE_OTHERS, PHS_SEND, DBG_LVL_ALL,"\nHeader Suppression Disabled For SF: No PHS\n");
			}

			return STATUS_SUCCESS;
		}
	}

	//BCM_DEBUG_PRINT(Adapter,DBG_TYPE_OTHERS, PHS_SEND, DBG_LVL_ALL,"PHSTransmit : Dumping data packet After PHS");
	return STATUS_SUCCESS;
}

int ip_forward(struct sk_buff *skb)
{
	struct net_device *dev2;	/* Output device */
	struct iphdr *iph;	/* Our header */
	struct rtable *rt;	/* Route we use */
	struct ip_options * opt	= &(IPCB(skb)->opt);
	unsigned short mtu;

	if (IPCB(skb)->opt.router_alert && ip_call_ra_chain(skb))
		return NET_RX_SUCCESS;

	if (skb->pkt_type != PACKET_HOST)
		goto drop;

	skb->ip_summed = CHECKSUM_NONE;
	
	/*
	 *	According to the RFC, we must first decrease the TTL field. If
	 *	that reaches zero, we must reply an ICMP control message telling
	 *	that the packet's lifetime expired.
	 */

	iph = skb->nh.iph;
	rt = (struct rtable*)skb->dst;

	if (iph->ttl <= 1)
                goto too_many_hops;

	if (opt->is_strictroute && rt->rt_dst != rt->rt_gateway)
                goto sr_failed;

	/*
	 *	Having picked a route we can now send the frame out
	 *	after asking the firewall permission to do so.
	 */

	skb->priority = rt_tos2priority(iph->tos);
	dev2 = rt->u.dst.dev;
	mtu = rt->u.dst.pmtu;

	/*
	 *	We now generate an ICMP HOST REDIRECT giving the route
	 *	we calculated.
	 */
	if (rt->rt_flags&RTCF_DOREDIRECT && !opt->srr)
		ip_rt_send_redirect(skb);

	/* We are about to mangle packet. Copy it! */
	if (skb_cow(skb, dev2->hard_header_len))
		goto drop;
	iph = skb->nh.iph;

	/* Decrease ttl after skb cow done */
	ip_decrease_ttl(iph);

	/*
	 * We now may allocate a new buffer, and copy the datagram into it.
	 * If the indicated interface is up and running, kick it.
	 */

	if (skb->len > mtu && (ntohs(iph->frag_off) & IP_DF))
		goto frag_needed;

#ifdef CONFIG_IP_ROUTE_NAT
	if (rt->rt_flags & RTCF_NAT) {
		if (ip_do_nat(skb)) {
			kfree_skb(skb);
			return NET_RX_BAD;
		}
	}
#endif

	return NF_HOOK(PF_INET, NF_IP_FORWARD, skb, skb->dev, dev2,
		       ip_forward_finish);

frag_needed:
	IP_INC_STATS_BH(IpFragFails);
	icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu));
        goto drop;

sr_failed:
        /*
	 *	Strict routing permits no gatewaying
	 */
         icmp_send(skb, ICMP_DEST_UNREACH, ICMP_SR_FAILED, 0);
         goto drop;

too_many_hops:
        /* Tell the sender its packet died... */
        icmp_send(skb, ICMP_TIME_EXCEEDED, ICMP_EXC_TTL, 0);
drop:
	kfree_skb(skb);
	return NET_RX_DROP;
}

static int mpls_xmit(struct sk_buff *skb)
{
	struct mpls_iptunnel_encap *tun_encap_info;
	struct mpls_shim_hdr *hdr;
	struct net_device *out_dev;
	unsigned int hh_len;
	unsigned int new_header_size;
	unsigned int mtu;
	struct dst_entry *dst = skb_dst(skb);
	struct rtable *rt = NULL;
	struct rt6_info *rt6 = NULL;
	int err = 0;
	bool bos;
	int i;
	unsigned int ttl;

	/* Obtain the ttl */
	if (dst->ops->family == AF_INET) {
		ttl = ip_hdr(skb)->ttl;
		rt = (struct rtable *)dst;
	} else if (dst->ops->family == AF_INET6) {
		ttl = ipv6_hdr(skb)->hop_limit;
		rt6 = (struct rt6_info *)dst;
	} else {
		goto drop;
	}

	skb_orphan(skb);

	/* Find the output device */
	out_dev = dst->dev;
	if (!mpls_output_possible(out_dev) ||
	    !dst->lwtstate || skb_warn_if_lro(skb))
		goto drop;

	skb_forward_csum(skb);

	tun_encap_info = mpls_lwtunnel_encap(dst->lwtstate);

	/* Verify the destination can hold the packet */
	new_header_size = mpls_encap_size(tun_encap_info);
	mtu = mpls_dev_mtu(out_dev);
	if (mpls_pkt_too_big(skb, mtu - new_header_size))
		goto drop;

	hh_len = LL_RESERVED_SPACE(out_dev);
	if (!out_dev->header_ops)
		hh_len = 0;

	/* Ensure there is enough space for the headers in the skb */
	if (skb_cow(skb, hh_len + new_header_size))
		goto drop;

	skb_set_inner_protocol(skb, skb->protocol);
	skb_reset_inner_network_header(skb);

	skb_push(skb, new_header_size);

	skb_reset_network_header(skb);

	skb->dev = out_dev;
	skb->protocol = htons(ETH_P_MPLS_UC);

	/* Push the new labels */
	hdr = mpls_hdr(skb);
	bos = true;
	for (i = tun_encap_info->labels - 1; i >= 0; i--) {
		hdr[i] = mpls_entry_encode(tun_encap_info->label[i],
					   ttl, 0, bos);
		bos = false;
	}

	if (rt)
		err = neigh_xmit(NEIGH_ARP_TABLE, out_dev, &rt->rt_gateway,
				 skb);
	else if (rt6)
		err = neigh_xmit(NEIGH_ND_TABLE, out_dev, &rt6->rt6i_gateway,
				 skb);
	if (err)
		net_dbg_ratelimited("%s: packet transmission failed: %d\n",
				    __func__, err);

	return LWTUNNEL_XMIT_DONE;

drop:
	kfree_skb(skb);
	return -EINVAL;
}

int
ip_vs_icmp_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
		struct ip_vs_protocol *pp, int offset, unsigned int hooknum,
		struct ip_vs_iphdr *ipvsh)
{
	struct rt6_info	*rt;	/* Route to the other host */
	int rc;
	int local;
	int rt_mode;

	EnterFunction(10);

	/* The ICMP packet for VS/TUN, VS/DR and LOCALNODE will be
	   forwarded directly here, because there is no need to
	   translate address/port back */
	if (IP_VS_FWD_METHOD(cp) != IP_VS_CONN_F_MASQ) {
		if (cp->packet_xmit)
			rc = cp->packet_xmit(skb, cp, pp, ipvsh);
		else
			rc = NF_ACCEPT;
		/* do not touch skb anymore */
		atomic_inc_unchecked(&cp->in_pkts);
		goto out;
	}

	/*
	 * mangle and send the packet here (only for VS/NAT)
	 */

	/* LOCALNODE from FORWARD hook is not supported */
	rt_mode = (hooknum != NF_INET_FORWARD) ?
		  IP_VS_RT_MODE_LOCAL | IP_VS_RT_MODE_NON_LOCAL |
		  IP_VS_RT_MODE_RDR : IP_VS_RT_MODE_NON_LOCAL;
	rcu_read_lock();
	local = __ip_vs_get_out_rt_v6(skb, cp->dest, &cp->daddr.in6, NULL,
				      ipvsh, 0, rt_mode);
	if (local < 0)
		goto tx_error;
	rt = (struct rt6_info *) skb_dst(skb);
	/*
	 * Avoid duplicate tuple in reply direction for NAT traffic
	 * to local address when connection is sync-ed
	 */
#if IS_ENABLED(CONFIG_NF_CONNTRACK)
	if (cp->flags & IP_VS_CONN_F_SYNC && local) {
		enum ip_conntrack_info ctinfo;
		struct nf_conn *ct = nf_ct_get(skb, &ctinfo);

		if (ct && !nf_ct_is_untracked(ct)) {
			IP_VS_DBG(10, "%s(): "
				  "stopping DNAT to local address %pI6\n",
				  __func__, &cp->daddr.in6);
			goto tx_error;
		}
	}
#endif

	/* From world but DNAT to loopback address? */
	if (local && skb->dev && !(skb->dev->flags & IFF_LOOPBACK) &&
	    ipv6_addr_type(&rt->rt6i_dst.addr) & IPV6_ADDR_LOOPBACK) {
		IP_VS_DBG(1, "%s(): "
			  "stopping DNAT to loopback %pI6\n",
			  __func__, &cp->daddr.in6);
		goto tx_error;
	}

	/* copy-on-write the packet before mangling it */
	if (!skb_make_writable(skb, offset))
		goto tx_error;

	if (skb_cow(skb, rt->dst.dev->hard_header_len))
		goto tx_error;

	ip_vs_nat_icmp_v6(skb, pp, cp, 0);

	/* Another hack: avoid icmp_send in ip_fragment */
	skb->local_df = 1;

	rc = ip_vs_nat_send_or_cont(NFPROTO_IPV6, skb, cp, local);
	rcu_read_unlock();
	goto out;

tx_error:
	kfree_skb(skb);
	rcu_read_unlock();
	rc = NF_STOLEN;
out:
	LeaveFunction(10);
	return rc;
}