qca-nss-clients/gre/nss_connmgr_gre_v4.c - manifest_repos/sdk - Git at Google

 /*
  **************************************************************************
  * Copyright (c) 2017-2018, 2020 The Linux Foundation. All rights reserved.
  * Permission to use, copy, modify, and/or distribute this software for
  * any purpose with or without fee is hereby granted, provided that the
  * above copyright notice and this permission notice appear in all copies.
  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  **************************************************************************
  */

 /*
  * nss_connnmgr_gre_v4.c
  *
  *  This file implements client for GRE implementation.
  */

 #include <linux/version.h>
 #include <linux/netdevice.h>
 #include <linux/inetdevice.h>
 #include <linux/etherdevice.h>
 #include <net/ip.h>
 #include <net/route.h>
 #include <net/ip_tunnels.h>
 #include <net/ip6_tunnel.h>
 #include <net/arp.h>
 #include <net/gre.h>

 #include <nss_api_if.h>
 #include "nss_connmgr_gre_public.h"
 #include "nss_connmgr_gre.h"

 /*
  * nss_connmgr_gre_v4_get_tx_dev()
  *	Find tx interface for IP address. Holds ref to next_dev.
  */
 static struct net_device *nss_connmgr_gre_v4_get_tx_dev(uint32_t dest_ip)
 {
 	struct rtable *rt;
 	struct net_device *dev;
 	uint32_t ip_addr __attribute__ ((unused)) = ntohl(dest_ip);

 	rt = ip_route_output(&init_net, htonl(dest_ip), 0, 0, 0);
 	if (IS_ERR(rt)) {
 		nss_connmgr_gre_warning("Unable to lookup route for %pI4\n", &ip_addr);
 		return NULL;
 	}

 	dev = rt->dst.dev;
 	if (!dev) {
 		ip_rt_put(rt);
 		nss_connmgr_gre_warning("Unable to find route dev for %pI4\n", &ip_addr);
 		return NULL;
 	}

 	dev_hold(dev);
 	ip_rt_put(rt);
 	return dev;
 }

 /*
  * nss_connmgr_gre_v4_get_mac_address()
  *	Find source and destination MAC for source and destination IP address.
  */
 static int nss_connmgr_gre_v4_get_mac_address(uint32_t src_ip, uint32_t dest_ip,
 					     uint8_t *src_mac, uint8_t *dest_mac)
 {
 	struct neighbour *neigh;
 	struct rtable *rt;
 	__be32 raddr = htonl(dest_ip);
 	__be32 laddr = htonl(src_ip);

 	/*
 	 * find local MAC address
 	 */
 	struct net_device *local_dev = ip_dev_find(&init_net, laddr);
 	if (!local_dev) {
 		nss_connmgr_gre_warning("Unable to find local dev for %pI4", &laddr);
 		return GRE_ERR_NO_LOCAL_NETDEV;
 	}
 	ether_addr_copy(src_mac, local_dev->dev_addr);
 	dev_put(local_dev);
 	nss_connmgr_gre_info("Src MAC address for %pI4 is %pM\n", &laddr, src_mac);

 	rt = ip_route_output(&init_net, raddr, 0, 0, 0);
 	if (IS_ERR(rt)) {
 		nss_connmgr_gre_warning("route look up failed for %pI4\n", &raddr);
 		return GRE_ERR_RADDR_ROUTE_LOOKUP;
 	}

 	neigh = dst_neigh_lookup(&rt->dst, (const void *)&raddr);
 	if (!neigh) {
 		neigh = neigh_lookup(&arp_tbl, (const void *)&raddr,  rt->dst.dev);
 	}

 	if (neigh) {
 		if (!(neigh->nud_state & NUD_VALID) || !is_valid_ether_addr(neigh->ha)) {
 			nss_connmgr_gre_info("neigh lookup failed for %pI4, state=%x, neigh->ha=%pM\n", &raddr, neigh->nud_state, neigh->ha);
 			neigh_release(neigh);
 			neigh = NULL;
 		}
 	}

 	/*
 	 * Send arp request
 	 */
 	if (!neigh) {
 		neigh = neigh_create(&arp_tbl, &raddr, rt->dst.dev);
 		if (IS_ERR_OR_NULL(neigh)) {
 			nss_connmgr_gre_warning("Unable to create ARP request neigh for %pI4\n", &raddr);
 			ip_rt_put(rt);
 			return GRE_ERR_NEIGH_CREATE;
 		}
 		nss_connmgr_gre_info("Send ARP request neigh for %pI4\n", &raddr);
 		neigh_event_send(neigh, NULL);

 		msleep(2000);
 	}

 	if (!(neigh->nud_state & NUD_VALID) || !is_valid_ether_addr(neigh->ha)) {
 		ip_rt_put(rt);
 		nss_connmgr_gre_warning("invalid neigh state (%x) or invalid MAC(%pM) for %pI4\n", neigh->nud_state, neigh->ha,  &raddr);
 		neigh_release(neigh);
 		return GRE_ERR_NEIGH_CREATE;
 	}

 	if (neigh->dev->type == ARPHRD_LOOPBACK) {
 		ip_rt_put(rt);
 		neigh_release(neigh);
 		nss_connmgr_gre_warning("Err in destination MAC address, neighbour dev is loop back for %pI4\n", &raddr);
 		return GRE_ERR_NEIGH_DEV_LOOPBACK;

 	}

 	if (neigh->dev->flags & IFF_NOARP) {
 		ip_rt_put(rt);
 		neigh_release(neigh);
 		nss_connmgr_gre_warning("Err in destination MAC address, neighbour dev is of type NO_ARP for %pI4\n", &raddr);
 		return GRE_ERR_NEIGH_DEV_NOARP;
 	}

 	ether_addr_copy(dest_mac, neigh->ha);
 	ip_rt_put(rt);
 	neigh_release(neigh);
 	nss_connmgr_gre_info("Destination MAC address for %pI4 is %pM\n", &raddr, dest_mac);
 	return GRE_SUCCESS;
 }

 /*
  * nss_connmgr_gre_v4_set_config()
  *	Set User configuration to netdevice
  */
 int nss_connmgr_gre_v4_set_config(struct net_device *dev, struct nss_connmgr_gre_cfg *cfg)
 {
 	nss_connmgr_gre_priv_t *priv = netdev_priv(dev);
 	struct ip_tunnel *t = (struct ip_tunnel *)priv;
 	struct iphdr *iphdr;

 	/*
 	 * MAC address validate
 	 */
 	if (cfg->use_mac_hdr) {
 		if (!is_valid_ether_addr((const u8 *)cfg->src_mac) ||
 		    !is_valid_ether_addr((const u8 *)cfg->dest_mac)) {
 			nss_connmgr_gre_warning("User should provide valid MAC address if flag add_mac hdr is set\n");
 			return GRE_ERR_INVALID_MAC;
 		}
 	}

 	/*
 	 * IP address validate
 	 */
 	if ((cfg->src_ip == 0) || (cfg->dest_ip == 0)) {
 		nss_connmgr_gre_warning("Source ip/Destination IP is invalid");
 		return GRE_ERR_INVALID_IP;
 	}

 	memset(t, 0, sizeof(struct ip_tunnel));

 	priv->pad_len =  (cfg->add_padding) ? GRE_HDR_PAD_LEN : 0;
 	priv->gre_hlen = nss_connmgr_gre_get_hlen(cfg);

 	iphdr = (struct iphdr *)&(t->parms.iph);
 	iphdr->protocol = IPPROTO_GRE;

 	memcpy(&iphdr->saddr, (uint8_t *)cfg->src_ip, 4);
 	memcpy(&iphdr->daddr, (uint8_t *)cfg->dest_ip, 4);

 	iphdr->saddr = htonl(iphdr->saddr);
 	iphdr->daddr = htonl(iphdr->daddr);

 	iphdr->tos = cfg->tos << 2;
 	if (cfg->tos_inherit) {
 		iphdr->tos |= 0x1;
 	}

 	iphdr->ttl = cfg->ttl;
 	if (cfg->ttl_inherit) {
 		iphdr->ttl = 0;
 	}

 	if (cfg->set_df) {
 		iphdr->frag_off = htons(IP_DF);
 	}

 	if (cfg->ikey_valid) {
 		t->parms.i_key = cfg->ikey;
 	}

 	if (cfg->okey_valid) {
 		t->parms.o_key = cfg->okey;
 	}

 	nss_connmgr_gre_set_gre_flags(cfg, &t->parms.o_flags, &t->parms.i_flags);

 	strlcpy(t->parms.name, dev->name, IFNAMSIZ);
 	t->dev = dev;
 	return GRE_SUCCESS;
 }

 /*
  * nss_connmgr_gre_tap_v4_outer_exception()
  * 	Handle IPv4 exception for GRETAP outer device
  */
 void nss_connmgr_gre_tap_v4_outer_exception(struct net_device *dev, struct sk_buff *skb)
 {
 	struct ethhdr *eth_hdr = (struct ethhdr *)skb->data;

 	/*
 	 * GRE encapsulated packet exceptioned, remove the encapsulation
 	 * and transmit on GRE interface.
 	 */
 	if (unlikely(!pskb_may_pull(skb, (sizeof(struct ethhdr) + sizeof(struct iphdr)
 				+ sizeof(struct gre_base_hdr))))) {
 		nss_connmgr_gre_warning("%px: pskb_may_pull failed for skb:%px\n", dev, skb);
 		dev_kfree_skb_any(skb);
 		return;
 	}

 	/*
 	 * TODO: Support parsing GRE options
 	 */
 	skb_pull(skb, (sizeof(struct ethhdr) + sizeof(struct iphdr)
 				+ sizeof(struct gre_base_hdr)));

 	if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr)))) {
 		nss_connmgr_gre_warning("%px: pskb_may_pull failed for skb:%px\n", dev, skb);
 		dev_kfree_skb_any(skb);
 		return;
 	}
 	skb->dev = dev;
 	if (likely(ntohs(eth_hdr->h_proto) >= ETH_P_802_3_MIN)) {
 		skb->protocol = eth_hdr->h_proto;
 	} else {
 		skb->protocol = htons(ETH_P_802_2);
 	}
 	skb_reset_mac_header(skb);
 	skb_reset_network_header(skb);
 	skb_reset_transport_header(skb);
 	skb_reset_mac_len(skb);
 	dev_queue_xmit(skb);
 }

 /*
  * nss_connmgr_gre_tun_v4_outer_exception()
  * 	Handle IPv4 exception for GRETUN outer device
  */
 void nss_connmgr_gre_tun_v4_outer_exception(struct net_device *dev, struct sk_buff *skb)
 {
 	struct iphdr *iph;

 	/*
 	 * GRE encapsulated packet exceptioned, remove the encapsulation
 	 * and transmit on GRE interface.
 	 */
 	if (unlikely(!pskb_may_pull(skb, sizeof(struct iphdr) + sizeof(struct gre_base_hdr)))) {
 		nss_connmgr_gre_warning("%px: pskb_may_pull failed for skb:%px\n", dev, skb);
 		dev_kfree_skb_any(skb);
 		return;
 	}

 	/*
 	 * TODO: Support parsing GRE options
 	 */
 	skb_pull(skb, sizeof(struct iphdr) + sizeof(struct gre_base_hdr));
 	iph = (struct iphdr *)skb->data;
 	skb->dev = dev;

 	switch (iph->version) {
 	case 4:
 		skb->protocol = htons(ETH_P_IP);
 		break;
 	case 6:
 		skb->protocol = htons(ETH_P_IPV6);
 		break;
 	default:
 		nss_connmgr_gre_info("%px: wrong IP version in GRE encapped packet. skb: %px\n", dev, skb);
 		dev_kfree_skb_any(skb);
 		return;
 	}

 	skb_reset_mac_header(skb);
 	skb_reset_network_header(skb);
 	skb_reset_transport_header(skb);
 	skb_reset_mac_len(skb);
 	dev_queue_xmit(skb);
 }

 /*
  * nss_connmgr_gre_v4_get_config()
  *	Fill in config message to send to NSS.
  */
 int nss_connmgr_gre_v4_get_config(struct net_device *dev, struct nss_gre_msg *req,
 				  struct net_device **next_dev, bool hold)
 {
 	uint32_t src_ip, dest_ip;
 	struct ip_tunnel *t = netdev_priv(dev);
 	struct iphdr *iphdr = (struct iphdr *)&(t->parms.iph);
 	struct net_device *out_dev;
 	struct nss_gre_config_msg *cmsg = &req->msg.cmsg;
 	int ret;

 	src_ip = ntohl(iphdr->saddr);
 	dest_ip = ntohl(iphdr->daddr);
 	memcpy(cmsg->src_ip, &src_ip, 4);
 	memcpy(cmsg->dest_ip, &dest_ip, 4);

 	cmsg->flags |= nss_connmgr_gre_get_nss_config_flags(t->parms.o_flags,
 								     t->parms.i_flags,
 								     iphdr->tos, iphdr->ttl,
 								     iphdr->frag_off);

 	cmsg->ikey = t->parms.i_key;
 	cmsg->okey = t->parms.o_key;
 	cmsg->ttl = iphdr->ttl;
 	cmsg->tos = iphdr->tos >> 2;

 	/*
 	 * fill in MAC addresses
 	 */
 	ret = nss_connmgr_gre_v4_get_mac_address(src_ip, dest_ip,
 						 (uint8_t *)cmsg->src_mac,
 						 (uint8_t *)cmsg->dest_mac);
 	if (!ret) {
 		cmsg->flags |= NSS_GRE_CONFIG_SET_MAC;
 	}

 	/*
 	 * fill in NSS interface number
 	 */
 	out_dev = nss_connmgr_gre_v4_get_tx_dev(dest_ip);
 	if (out_dev) {
 		cmsg->next_node_if_num = nss_cmn_get_interface_number_by_dev(out_dev);
 		cmsg->flags |= NSS_GRE_CONFIG_NEXT_NODE_AVAILABLE;
 		*next_dev = out_dev;
 		if (!hold) {
 			dev_put(out_dev);
 		}
 	}

 	return GRE_SUCCESS;
 }
	/*
	**************************************************************************
	* Copyright (c) 2017-2018, 2020 The Linux Foundation. All rights reserved.
	* Permission to use, copy, modify, and/or distribute this software for
	* any purpose with or without fee is hereby granted, provided that the
	* above copyright notice and this permission notice appear in all copies.
	* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
	* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
	* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
	* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
	* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
	* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
	* OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
	**************************************************************************
	*/

	/*
	* nss_connnmgr_gre_v4.c
	*
	* This file implements client for GRE implementation.
	*/

	#include <linux/version.h>
	#include <linux/netdevice.h>
	#include <linux/inetdevice.h>
	#include <linux/etherdevice.h>
	#include <net/ip.h>
	#include <net/route.h>
	#include <net/ip_tunnels.h>
	#include <net/ip6_tunnel.h>
	#include <net/arp.h>
	#include <net/gre.h>

	#include <nss_api_if.h>
	#include "nss_connmgr_gre_public.h"
	#include "nss_connmgr_gre.h"

	/*
	* nss_connmgr_gre_v4_get_tx_dev()
	* Find tx interface for IP address. Holds ref to next_dev.
	*/
	static struct net_device *nss_connmgr_gre_v4_get_tx_dev(uint32_t dest_ip)
	{
	struct rtable *rt;
	struct net_device *dev;
	uint32_t ip_addr __attribute__ ((unused)) = ntohl(dest_ip);

	rt = ip_route_output(&init_net, htonl(dest_ip), 0, 0, 0);
	if (IS_ERR(rt)) {
	nss_connmgr_gre_warning("Unable to lookup route for %pI4\n", &ip_addr);
	return NULL;
	}

	dev = rt->dst.dev;
	if (!dev) {
	ip_rt_put(rt);
	nss_connmgr_gre_warning("Unable to find route dev for %pI4\n", &ip_addr);
	return NULL;
	}

	dev_hold(dev);
	ip_rt_put(rt);
	return dev;
	}

	/*
	* nss_connmgr_gre_v4_get_mac_address()
	* Find source and destination MAC for source and destination IP address.
	*/
	static int nss_connmgr_gre_v4_get_mac_address(uint32_t src_ip, uint32_t dest_ip,
	uint8_t src_mac, uint8_t dest_mac)
	{
	struct neighbour *neigh;
	struct rtable *rt;
	__be32 raddr = htonl(dest_ip);
	__be32 laddr = htonl(src_ip);

	/*
	* find local MAC address
	*/
	struct net_device *local_dev = ip_dev_find(&init_net, laddr);
	if (!local_dev) {
	nss_connmgr_gre_warning("Unable to find local dev for %pI4", &laddr);
	return GRE_ERR_NO_LOCAL_NETDEV;
	}
	ether_addr_copy(src_mac, local_dev->dev_addr);
	dev_put(local_dev);
	nss_connmgr_gre_info("Src MAC address for %pI4 is %pM\n", &laddr, src_mac);

	rt = ip_route_output(&init_net, raddr, 0, 0, 0);
	if (IS_ERR(rt)) {
	nss_connmgr_gre_warning("route look up failed for %pI4\n", &raddr);
	return GRE_ERR_RADDR_ROUTE_LOOKUP;
	}

	neigh = dst_neigh_lookup(&rt->dst, (const void *)&raddr);
	if (!neigh) {
	neigh = neigh_lookup(&arp_tbl, (const void *)&raddr, rt->dst.dev);
	}

	if (neigh) {
	if (!(neigh->nud_state & NUD_VALID) \|\| !is_valid_ether_addr(neigh->ha)) {
	nss_connmgr_gre_info("neigh lookup failed for %pI4, state=%x, neigh->ha=%pM\n", &raddr, neigh->nud_state, neigh->ha);
	neigh_release(neigh);
	neigh = NULL;
	}
	}

	/*
	* Send arp request
	*/
	if (!neigh) {
	neigh = neigh_create(&arp_tbl, &raddr, rt->dst.dev);
	if (IS_ERR_OR_NULL(neigh)) {
	nss_connmgr_gre_warning("Unable to create ARP request neigh for %pI4\n", &raddr);
	ip_rt_put(rt);
	return GRE_ERR_NEIGH_CREATE;
	}
	nss_connmgr_gre_info("Send ARP request neigh for %pI4\n", &raddr);
	neigh_event_send(neigh, NULL);

	msleep(2000);
	}

	if (!(neigh->nud_state & NUD_VALID) \|\| !is_valid_ether_addr(neigh->ha)) {
	ip_rt_put(rt);
	nss_connmgr_gre_warning("invalid neigh state (%x) or invalid MAC(%pM) for %pI4\n", neigh->nud_state, neigh->ha, &raddr);
	neigh_release(neigh);
	return GRE_ERR_NEIGH_CREATE;
	}

	if (neigh->dev->type == ARPHRD_LOOPBACK) {
	ip_rt_put(rt);
	neigh_release(neigh);
	nss_connmgr_gre_warning("Err in destination MAC address, neighbour dev is loop back for %pI4\n", &raddr);
	return GRE_ERR_NEIGH_DEV_LOOPBACK;

	}

	if (neigh->dev->flags & IFF_NOARP) {
	ip_rt_put(rt);
	neigh_release(neigh);
	nss_connmgr_gre_warning("Err in destination MAC address, neighbour dev is of type NO_ARP for %pI4\n", &raddr);
	return GRE_ERR_NEIGH_DEV_NOARP;
	}

	ether_addr_copy(dest_mac, neigh->ha);
	ip_rt_put(rt);
	neigh_release(neigh);
	nss_connmgr_gre_info("Destination MAC address for %pI4 is %pM\n", &raddr, dest_mac);
	return GRE_SUCCESS;
	}

	/*
	* nss_connmgr_gre_v4_set_config()
	* Set User configuration to netdevice
	*/
	int nss_connmgr_gre_v4_set_config(struct net_device dev, struct nss_connmgr_gre_cfg cfg)
	{
	nss_connmgr_gre_priv_t *priv = netdev_priv(dev);
	struct ip_tunnel t = (struct ip_tunnel )priv;
	struct iphdr *iphdr;

	/*
	* MAC address validate
	*/
	if (cfg->use_mac_hdr) {
	if (!is_valid_ether_addr((const u8 *)cfg->src_mac) \|\|
	!is_valid_ether_addr((const u8 *)cfg->dest_mac)) {
	nss_connmgr_gre_warning("User should provide valid MAC address if flag add_mac hdr is set\n");
	return GRE_ERR_INVALID_MAC;
	}
	}

	/*
	* IP address validate
	*/
	if ((cfg->src_ip == 0) \|\| (cfg->dest_ip == 0)) {
	nss_connmgr_gre_warning("Source ip/Destination IP is invalid");
	return GRE_ERR_INVALID_IP;
	}

	memset(t, 0, sizeof(struct ip_tunnel));

	priv->pad_len = (cfg->add_padding) ? GRE_HDR_PAD_LEN : 0;
	priv->gre_hlen = nss_connmgr_gre_get_hlen(cfg);

	iphdr = (struct iphdr *)&(t->parms.iph);
	iphdr->protocol = IPPROTO_GRE;

	memcpy(&iphdr->saddr, (uint8_t *)cfg->src_ip, 4);
	memcpy(&iphdr->daddr, (uint8_t *)cfg->dest_ip, 4);

	iphdr->saddr = htonl(iphdr->saddr);
	iphdr->daddr = htonl(iphdr->daddr);

	iphdr->tos = cfg->tos << 2;
	if (cfg->tos_inherit) {
	iphdr->tos \|= 0x1;
	}

	iphdr->ttl = cfg->ttl;
	if (cfg->ttl_inherit) {
	iphdr->ttl = 0;
	}

	if (cfg->set_df) {
	iphdr->frag_off = htons(IP_DF);
	}

	if (cfg->ikey_valid) {
	t->parms.i_key = cfg->ikey;
	}

	if (cfg->okey_valid) {
	t->parms.o_key = cfg->okey;
	}

	nss_connmgr_gre_set_gre_flags(cfg, &t->parms.o_flags, &t->parms.i_flags);

	strlcpy(t->parms.name, dev->name, IFNAMSIZ);
	t->dev = dev;
	return GRE_SUCCESS;
	}

	/*
	* nss_connmgr_gre_tap_v4_outer_exception()
	* Handle IPv4 exception for GRETAP outer device
	*/
	void nss_connmgr_gre_tap_v4_outer_exception(struct net_device dev, struct sk_buff skb)
	{
	struct ethhdr eth_hdr = (struct ethhdr )skb->data;

	/*
	* GRE encapsulated packet exceptioned, remove the encapsulation
	* and transmit on GRE interface.
	*/
	if (unlikely(!pskb_may_pull(skb, (sizeof(struct ethhdr) + sizeof(struct iphdr)
	+ sizeof(struct gre_base_hdr))))) {
	nss_connmgr_gre_warning("%px: pskb_may_pull failed for skb:%px\n", dev, skb);
	dev_kfree_skb_any(skb);
	return;
	}

	/*
	* TODO: Support parsing GRE options
	*/
	skb_pull(skb, (sizeof(struct ethhdr) + sizeof(struct iphdr)
	+ sizeof(struct gre_base_hdr)));

	if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr)))) {
	nss_connmgr_gre_warning("%px: pskb_may_pull failed for skb:%px\n", dev, skb);
	dev_kfree_skb_any(skb);
	return;
	}
	skb->dev = dev;
	if (likely(ntohs(eth_hdr->h_proto) >= ETH_P_802_3_MIN)) {
	skb->protocol = eth_hdr->h_proto;
	} else {
	skb->protocol = htons(ETH_P_802_2);
	}
	skb_reset_mac_header(skb);
	skb_reset_network_header(skb);
	skb_reset_transport_header(skb);
	skb_reset_mac_len(skb);
	dev_queue_xmit(skb);
	}

	/*
	* nss_connmgr_gre_tun_v4_outer_exception()
	* Handle IPv4 exception for GRETUN outer device
	*/
	void nss_connmgr_gre_tun_v4_outer_exception(struct net_device dev, struct sk_buff skb)
	{
	struct iphdr *iph;

	/*
	* GRE encapsulated packet exceptioned, remove the encapsulation
	* and transmit on GRE interface.
	*/
	if (unlikely(!pskb_may_pull(skb, sizeof(struct iphdr) + sizeof(struct gre_base_hdr)))) {
	nss_connmgr_gre_warning("%px: pskb_may_pull failed for skb:%px\n", dev, skb);
	dev_kfree_skb_any(skb);
	return;
	}

	/*
	* TODO: Support parsing GRE options
	*/
	skb_pull(skb, sizeof(struct iphdr) + sizeof(struct gre_base_hdr));
	iph = (struct iphdr *)skb->data;
	skb->dev = dev;

	switch (iph->version) {
	case 4:
	skb->protocol = htons(ETH_P_IP);
	break;
	case 6:
	skb->protocol = htons(ETH_P_IPV6);
	break;
	default:
	nss_connmgr_gre_info("%px: wrong IP version in GRE encapped packet. skb: %px\n", dev, skb);
	dev_kfree_skb_any(skb);
	return;
	}

	skb_reset_mac_header(skb);
	skb_reset_network_header(skb);
	skb_reset_transport_header(skb);
	skb_reset_mac_len(skb);
	dev_queue_xmit(skb);
	}

	/*
	* nss_connmgr_gre_v4_get_config()
	* Fill in config message to send to NSS.
	*/
	int nss_connmgr_gre_v4_get_config(struct net_device dev, struct nss_gre_msg req,
	struct net_device **next_dev, bool hold)
	{
	uint32_t src_ip, dest_ip;
	struct ip_tunnel *t = netdev_priv(dev);
	struct iphdr iphdr = (struct iphdr )&(t->parms.iph);
	struct net_device *out_dev;
	struct nss_gre_config_msg *cmsg = &req->msg.cmsg;
	int ret;

	src_ip = ntohl(iphdr->saddr);
	dest_ip = ntohl(iphdr->daddr);
	memcpy(cmsg->src_ip, &src_ip, 4);
	memcpy(cmsg->dest_ip, &dest_ip, 4);

	cmsg->flags \|= nss_connmgr_gre_get_nss_config_flags(t->parms.o_flags,
	t->parms.i_flags,
	iphdr->tos, iphdr->ttl,
	iphdr->frag_off);

	cmsg->ikey = t->parms.i_key;
	cmsg->okey = t->parms.o_key;
	cmsg->ttl = iphdr->ttl;
	cmsg->tos = iphdr->tos >> 2;

	/*
	* fill in MAC addresses
	*/
	ret = nss_connmgr_gre_v4_get_mac_address(src_ip, dest_ip,
	(uint8_t *)cmsg->src_mac,
	(uint8_t *)cmsg->dest_mac);
	if (!ret) {
	cmsg->flags \|= NSS_GRE_CONFIG_SET_MAC;
	}

	/*
	* fill in NSS interface number
	*/
	out_dev = nss_connmgr_gre_v4_get_tx_dev(dest_ip);
	if (out_dev) {
	cmsg->next_node_if_num = nss_cmn_get_interface_number_by_dev(out_dev);
	cmsg->flags \|= NSS_GRE_CONFIG_NEXT_NODE_AVAILABLE;
	*next_dev = out_dev;
	if (!hold) {
	dev_put(out_dev);
	}
	}

	return GRE_SUCCESS;
	}