76    - traceroute does not work. I planned to relay ICMP from tunnel,
94    (branches, that exceed pmtu are pruned) and tunnel mtu
275 	struct ip_tunnel *tunnel;  in erspan_rcv()  local
288 		tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, flags,  in erspan_rcv()
299 		tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, flags,  in erspan_rcv()
303 	if (tunnel) {  in erspan_rcv()
318 		if (tunnel->collect_md) {  in erspan_rcv()
354 		ip_tunnel_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);  in erspan_rcv()
369 	struct ip_tunnel *tunnel;  in __ipgre_rcv()  local
372 	tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, tpi->flags,  in __ipgre_rcv()
375 	if (tunnel) {  in __ipgre_rcv()
385 		if (tunnel->dev->header_ops == &ipgre_header_ops)  in __ipgre_rcv()
390 		tnl_params = &tunnel->parms.iph;  in __ipgre_rcv()
391 		if (tunnel->collect_md || tnl_params->daddr == 0) {  in __ipgre_rcv()
405 		ip_tunnel_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);  in __ipgre_rcv()
477 	struct ip_tunnel *tunnel = netdev_priv(dev);  in __gre_xmit()  local
480 	ip_tunnel_flags_copy(flags, tunnel->parms.o_flags);  in __gre_xmit()
483 	gre_build_header(skb, tunnel->tun_hlen,  in __gre_xmit()
484 			 flags, proto, tunnel->parms.o_key,  in __gre_xmit()
486 			 htonl(atomic_fetch_inc(&tunnel->o_seqno)) : 0);  in __gre_xmit()
499 	struct ip_tunnel *tunnel = netdev_priv(dev);  in gre_fb_xmit()  local
516 	/* Push Tunnel header. */  in gre_fb_xmit()
518 					      tunnel->parms.o_flags)))  in gre_fb_xmit()
529 			 htonl(atomic_fetch_inc(&tunnel->o_seqno)) : 0);  in gre_fb_xmit()
542 	struct ip_tunnel *tunnel = netdev_priv(dev);  in erspan_fb_xmit()  local
614 			 htonl(atomic_fetch_inc(&tunnel->o_seqno)));  in erspan_fb_xmit()
652 	struct ip_tunnel *tunnel = netdev_priv(dev);  in ipgre_xmit()  local
658 	if (tunnel->collect_md) {  in ipgre_xmit()
664 		int pull_len = tunnel->hlen + sizeof(struct iphdr);  in ipgre_xmit()
685 		tnl_params = &tunnel->parms.iph;  in ipgre_xmit()
689 					      tunnel->parms.o_flags)))  in ipgre_xmit()
704 	struct ip_tunnel *tunnel = netdev_priv(dev);  in erspan_xmit()  local
711 	if (tunnel->collect_md) {  in erspan_xmit()
729 	if (tunnel->erspan_ver == 0) {  in erspan_xmit()
731 		__clear_bit(IP_TUNNEL_SEQ_BIT, tunnel->parms.o_flags);  in erspan_xmit()
732 	} else if (tunnel->erspan_ver == 1) {  in erspan_xmit()
733 		erspan_build_header(skb, ntohl(tunnel->parms.o_key),  in erspan_xmit()
734 				    tunnel->index,  in erspan_xmit()
737 	} else if (tunnel->erspan_ver == 2) {  in erspan_xmit()
738 		erspan_build_header_v2(skb, ntohl(tunnel->parms.o_key),  in erspan_xmit()
739 				       tunnel->dir, tunnel->hwid,  in erspan_xmit()
746 	__clear_bit(IP_TUNNEL_KEY_BIT, tunnel->parms.o_flags);  in erspan_xmit()
747 	__gre_xmit(skb, dev, &tunnel->parms.iph, proto);  in erspan_xmit()
759 	struct ip_tunnel *tunnel = netdev_priv(dev);  in gre_tap_xmit()  local
764 	if (tunnel->collect_md) {  in gre_tap_xmit()
770 					      tunnel->parms.o_flags)))  in gre_tap_xmit()
776 	__gre_xmit(skb, dev, &tunnel->parms.iph, htons(ETH_P_TEB));  in gre_tap_xmit()
787 	struct ip_tunnel *tunnel = netdev_priv(dev);  in ipgre_link_update()  local
790 	len = tunnel->tun_hlen;  in ipgre_link_update()
791 	tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags);  in ipgre_link_update()
792 	len = tunnel->tun_hlen - len;  in ipgre_link_update()
793 	tunnel->hlen = tunnel->hlen + len;  in ipgre_link_update()
803 	if (test_bit(IP_TUNNEL_SEQ_BIT, tunnel->parms.o_flags) ||  in ipgre_link_update()
804 	    (test_bit(IP_TUNNEL_CSUM_BIT, tunnel->parms.o_flags) &&  in ipgre_link_update()
805 	     tunnel->encap.type != TUNNEL_ENCAP_NONE)) {  in ipgre_link_update()
877    ip tunnel add Universe mode gre remote 224.66.66.66 local <Your_real_addr> ttl 255
998 	struct ip_tunnel *tunnel;  in __gre_tunnel_init()  local
1000 	tunnel = netdev_priv(dev);  in __gre_tunnel_init()
1001 	tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags);  in __gre_tunnel_init()
1002 	tunnel->parms.iph.protocol = IPPROTO_GRE;  in __gre_tunnel_init()
1004 	tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen;  in __gre_tunnel_init()
1005 	dev->needed_headroom = tunnel->hlen + sizeof(tunnel->parms.iph);  in __gre_tunnel_init()
1013 	if (test_bit(IP_TUNNEL_SEQ_BIT, tunnel->parms.o_flags))  in __gre_tunnel_init()
1015 	if (test_bit(IP_TUNNEL_CSUM_BIT, tunnel->parms.o_flags) &&  in __gre_tunnel_init()
1016 	    tunnel->encap.type != TUNNEL_ENCAP_NONE)  in __gre_tunnel_init()
1027 	struct ip_tunnel *tunnel = netdev_priv(dev);  in ipgre_tunnel_init()  local
1028 	struct iphdr *iph = &tunnel->parms.iph;  in ipgre_tunnel_init()
1039 	if (iph->daddr && !tunnel->collect_md) {  in ipgre_tunnel_init()
1046 			dev->hard_header_len = tunnel->hlen + sizeof(*iph);  in ipgre_tunnel_init()
1050 	} else if (!tunnel->collect_md) {  in ipgre_tunnel_init()
1052 		dev->hard_header_len = tunnel->hlen + sizeof(*iph);  in ipgre_tunnel_init()
1342 	struct ip_tunnel *tunnel = netdev_priv(dev);  in erspan_tunnel_init()  local
1344 	if (tunnel->erspan_ver == 0)  in erspan_tunnel_init()
1345 		tunnel->tun_hlen = 4; /* 4-byte GRE hdr. */  in erspan_tunnel_init()
1347 		tunnel->tun_hlen = 8; /* 8-byte GRE hdr. */  in erspan_tunnel_init()
1349 	tunnel->parms.iph.protocol = IPPROTO_GRE;  in erspan_tunnel_init()
1350 	tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen +  in erspan_tunnel_init()
1351 		       erspan_hdr_len(tunnel->erspan_ver);  in erspan_tunnel_init()