[mirror_ubuntu-artful-kernel.git] / net / ipv6 / ip6_offload.c

/*
 *	IPV6 GSO/GRO offload support
 *	Linux INET6 implementation
 *
 *	This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      as published by the Free Software Foundation; either version
 *      2 of the License, or (at your option) any later version.
 */

#include <linux/kernel.h>
#include <linux/socket.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/printk.h>

#include <net/protocol.h>
#include <net/ipv6.h>
#include <net/inet_common.h>

#include "ip6_offload.h"

static int ipv6_gso_pull_exthdrs(struct sk_buff *skb, int proto)
{
	const struct net_offload *ops = NULL;

	for (;;) {
		struct ipv6_opt_hdr *opth;
		int len;

		if (proto != NEXTHDR_HOP) {
			ops = rcu_dereference(inet6_offloads[proto]);

			if (unlikely(!ops))
				break;

			if (!(ops->flags & INET6_PROTO_GSO_EXTHDR))
				break;
		}

		if (unlikely(!pskb_may_pull(skb, 8)))
			break;

		opth = (void *)skb->data;
		len = ipv6_optlen(opth);

		if (unlikely(!pskb_may_pull(skb, len)))
			break;

		opth = (void *)skb->data;
		proto = opth->nexthdr;
		__skb_pull(skb, len);
	}

	return proto;
}

static struct sk_buff *ipv6_gso_segment(struct sk_buff *skb,
	netdev_features_t features)
{
	struct sk_buff *segs = ERR_PTR(-EINVAL);
	struct ipv6hdr *ipv6h;
	const struct net_offload *ops;
	int proto;
	struct frag_hdr *fptr;
	unsigned int unfrag_ip6hlen;
	unsigned int payload_len;
	u8 *prevhdr;
	int offset = 0;
	bool encap, udpfrag;
	int nhoff;
	bool gso_partial;

	skb_reset_network_header(skb);
	nhoff = skb_network_header(skb) - skb_mac_header(skb);
	if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h))))
		goto out;

	encap = SKB_GSO_CB(skb)->encap_level > 0;
	if (encap)
		features &= skb->dev->hw_enc_features;
	SKB_GSO_CB(skb)->encap_level += sizeof(*ipv6h);

	ipv6h = ipv6_hdr(skb);
	__skb_pull(skb, sizeof(*ipv6h));
	segs = ERR_PTR(-EPROTONOSUPPORT);

	proto = ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr);

	if (skb->encapsulation &&
	    skb_shinfo(skb)->gso_type & (SKB_GSO_IPXIP4 | SKB_GSO_IPXIP6))
		udpfrag = proto == IPPROTO_UDP && encap;
	else
		udpfrag = proto == IPPROTO_UDP && !skb->encapsulation;

	ops = rcu_dereference(inet6_offloads[proto]);
	if (likely(ops && ops->callbacks.gso_segment)) {
		skb_reset_transport_header(skb);
		segs = ops->callbacks.gso_segment(skb, features);
	}

	if (IS_ERR_OR_NULL(segs))
		goto out;

	gso_partial = !!(skb_shinfo(segs)->gso_type & SKB_GSO_PARTIAL);

	for (skb = segs; skb; skb = skb->next) {
		ipv6h = (struct ipv6hdr *)(skb_mac_header(skb) + nhoff);
		if (gso_partial)
			payload_len = skb_shinfo(skb)->gso_size +
				      SKB_GSO_CB(skb)->data_offset +
				      skb->head - (unsigned char *)(ipv6h + 1);
		else
			payload_len = skb->len - nhoff - sizeof(*ipv6h);
		ipv6h->payload_len = htons(payload_len);
		skb->network_header = (u8 *)ipv6h - skb->head;

		if (udpfrag) {
			unfrag_ip6hlen = ip6_find_1stfragopt(skb, &prevhdr);
			fptr = (struct frag_hdr *)((u8 *)ipv6h + unfrag_ip6hlen);
			fptr->frag_off = htons(offset);
			if (skb->next)
				fptr->frag_off |= htons(IP6_MF);
			offset += (ntohs(ipv6h->payload_len) -
				   sizeof(struct frag_hdr));
		}
		if (encap)
			skb_reset_inner_headers(skb);
	}

out:
	return segs;
}

/* Return the total length of all the extension hdrs, following the same
 * logic in ipv6_gso_pull_exthdrs() when parsing ext-hdrs.
 */
static int ipv6_exthdrs_len(struct ipv6hdr *iph,
			    const struct net_offload **opps)
{
	struct ipv6_opt_hdr *opth = (void *)iph;
	int len = 0, proto, optlen = sizeof(*iph);

	proto = iph->nexthdr;
	for (;;) {
		if (proto != NEXTHDR_HOP) {
			*opps = rcu_dereference(inet6_offloads[proto]);
			if (unlikely(!(*opps)))
				break;
			if (!((*opps)->flags & INET6_PROTO_GSO_EXTHDR))
				break;
		}
		opth = (void *)opth + optlen;
		optlen = ipv6_optlen(opth);
		len += optlen;
		proto = opth->nexthdr;
	}
	return len;
}

static struct sk_buff **ipv6_gro_receive(struct sk_buff **head,
					 struct sk_buff *skb)
{
	const struct net_offload *ops;
	struct sk_buff **pp = NULL;
	struct sk_buff *p;
	struct ipv6hdr *iph;
	unsigned int nlen;
	unsigned int hlen;
	unsigned int off;
	u16 flush = 1;
	int proto;

	off = skb_gro_offset(skb);
	hlen = off + sizeof(*iph);
	iph = skb_gro_header_fast(skb, off);
	if (skb_gro_header_hard(skb, hlen)) {
		iph = skb_gro_header_slow(skb, hlen, off);
		if (unlikely(!iph))
			goto out;
	}

	skb_set_network_header(skb, off);
	skb_gro_pull(skb, sizeof(*iph));
	skb_set_transport_header(skb, skb_gro_offset(skb));

	flush += ntohs(iph->payload_len) != skb_gro_len(skb);

	rcu_read_lock();
	proto = iph->nexthdr;
	ops = rcu_dereference(inet6_offloads[proto]);
	if (!ops || !ops->callbacks.gro_receive) {
		__pskb_pull(skb, skb_gro_offset(skb));
		proto = ipv6_gso_pull_exthdrs(skb, proto);
		skb_gro_pull(skb, -skb_transport_offset(skb));
		skb_reset_transport_header(skb);
		__skb_push(skb, skb_gro_offset(skb));

		ops = rcu_dereference(inet6_offloads[proto]);
		if (!ops || !ops->callbacks.gro_receive)
			goto out_unlock;

		iph = ipv6_hdr(skb);
	}

	NAPI_GRO_CB(skb)->proto = proto;

	flush--;
	nlen = skb_network_header_len(skb);

	for (p = *head; p; p = p->next) {
		const struct ipv6hdr *iph2;
		__be32 first_word; /* <Version:4><Traffic_Class:8><Flow_Label:20> */

		if (!NAPI_GRO_CB(p)->same_flow)
			continue;

		iph2 = (struct ipv6hdr *)(p->data + off);
		first_word = *(__be32 *)iph ^ *(__be32 *)iph2;

		/* All fields must match except length and Traffic Class.
		 * XXX skbs on the gro_list have all been parsed and pulled
		 * already so we don't need to compare nlen
		 * (nlen != (sizeof(*iph2) + ipv6_exthdrs_len(iph2, &ops)))
		 * memcmp() alone below is suffcient, right?
		 */
		 if ((first_word & htonl(0xF00FFFFF)) ||
		    memcmp(&iph->nexthdr, &iph2->nexthdr,
			   nlen - offsetof(struct ipv6hdr, nexthdr))) {
			NAPI_GRO_CB(p)->same_flow = 0;
			continue;
		}
		/* flush if Traffic Class fields are different */
		NAPI_GRO_CB(p)->flush |= !!(first_word & htonl(0x0FF00000));
		NAPI_GRO_CB(p)->flush |= flush;

		/* If the previous IP ID value was based on an atomic
		 * datagram we can overwrite the value and ignore it.
		 */
		if (NAPI_GRO_CB(skb)->is_atomic)
			NAPI_GRO_CB(p)->flush_id = 0;
	}

	NAPI_GRO_CB(skb)->is_atomic = true;
	NAPI_GRO_CB(skb)->flush |= flush;

	skb_gro_postpull_rcsum(skb, iph, nlen);

	pp = call_gro_receive(ops->callbacks.gro_receive, head, skb);

out_unlock:
	rcu_read_unlock();

out:
	NAPI_GRO_CB(skb)->flush |= flush;

	return pp;
}

static struct sk_buff **sit_ip6ip6_gro_receive(struct sk_buff **head,
					       struct sk_buff *skb)
{
	/* Common GRO receive for SIT and IP6IP6 */

	if (NAPI_GRO_CB(skb)->encap_mark) {
		NAPI_GRO_CB(skb)->flush = 1;
		return NULL;
	}

	NAPI_GRO_CB(skb)->encap_mark = 1;

	return ipv6_gro_receive(head, skb);
}

static struct sk_buff **ip4ip6_gro_receive(struct sk_buff **head,
					   struct sk_buff *skb)
{
	/* Common GRO receive for SIT and IP6IP6 */

	if (NAPI_GRO_CB(skb)->encap_mark) {
		NAPI_GRO_CB(skb)->flush = 1;
		return NULL;
	}

	NAPI_GRO_CB(skb)->encap_mark = 1;

	return inet_gro_receive(head, skb);
}

static int ipv6_gro_complete(struct sk_buff *skb, int nhoff)
{
	const struct net_offload *ops;
	struct ipv6hdr *iph = (struct ipv6hdr *)(skb->data + nhoff);
	int err = -ENOSYS;

	if (skb->encapsulation)
		skb_set_inner_network_header(skb, nhoff);

	iph->payload_len = htons(skb->len - nhoff - sizeof(*iph));

	rcu_read_lock();

	nhoff += sizeof(*iph) + ipv6_exthdrs_len(iph, &ops);
	if (WARN_ON(!ops || !ops->callbacks.gro_complete))
		goto out_unlock;

	err = ops->callbacks.gro_complete(skb, nhoff);

out_unlock:
	rcu_read_unlock();

	return err;
}

static int sit_gro_complete(struct sk_buff *skb, int nhoff)
{
	skb->encapsulation = 1;
	skb_shinfo(skb)->gso_type |= SKB_GSO_IPXIP4;
	return ipv6_gro_complete(skb, nhoff);
}

static int ip6ip6_gro_complete(struct sk_buff *skb, int nhoff)
{
	skb->encapsulation = 1;
	skb_shinfo(skb)->gso_type |= SKB_GSO_IPXIP6;
	return ipv6_gro_complete(skb, nhoff);
}

static int ip4ip6_gro_complete(struct sk_buff *skb, int nhoff)
{
	skb->encapsulation = 1;
	skb_shinfo(skb)->gso_type |= SKB_GSO_IPXIP6;
	return inet_gro_complete(skb, nhoff);
}

static struct packet_offload ipv6_packet_offload __read_mostly = {
	.type = cpu_to_be16(ETH_P_IPV6),
	.callbacks = {
		.gso_segment = ipv6_gso_segment,
		.gro_receive = ipv6_gro_receive,
		.gro_complete = ipv6_gro_complete,
	},
};

static const struct net_offload sit_offload = {
	.callbacks = {
		.gso_segment	= ipv6_gso_segment,
		.gro_receive    = sit_ip6ip6_gro_receive,
		.gro_complete   = sit_gro_complete,
	},
};

static const struct net_offload ip4ip6_offload = {
	.callbacks = {
		.gso_segment	= inet_gso_segment,
		.gro_receive    = ip4ip6_gro_receive,
		.gro_complete   = ip4ip6_gro_complete,
	},
};

static const struct net_offload ip6ip6_offload = {
	.callbacks = {
		.gso_segment	= ipv6_gso_segment,
		.gro_receive    = sit_ip6ip6_gro_receive,
		.gro_complete   = ip6ip6_gro_complete,
	},
};
static int __init ipv6_offload_init(void)
{

	if (tcpv6_offload_init() < 0)
		pr_crit("%s: Cannot add TCP protocol offload\n", __func__);
	if (ipv6_exthdrs_offload_init() < 0)
		pr_crit("%s: Cannot add EXTHDRS protocol offload\n", __func__);

	dev_add_offload(&ipv6_packet_offload);

	inet_add_offload(&sit_offload, IPPROTO_IPV6);
	inet6_add_offload(&ip6ip6_offload, IPPROTO_IPV6);
	inet6_add_offload(&ip4ip6_offload, IPPROTO_IPIP);

	return 0;
}

fs_initcall(ipv6_offload_init);
Commit	Line	Data
d1da932e VY	1	/*
	2	* IPV6 GSO/GRO offload support
	3	* Linux INET6 implementation
	4	*
	5	* This program is free software; you can redistribute it and/or
	6	* modify it under the terms of the GNU General Public License
	7	* as published by the Free Software Foundation; either version
	8	* 2 of the License, or (at your option) any later version.
	9	*/
	10
	11	#include <linux/kernel.h>
	12	#include <linux/socket.h>
	13	#include <linux/netdevice.h>
	14	#include <linux/skbuff.h>
c6b641a4	15	#include <linux/printk.h>
d1da932e VY	16
	17	#include <net/protocol.h>
	18	#include <net/ipv6.h>
b8921ca8	19	#include <net/inet_common.h>
d1da932e VY	20
	21	#include "ip6_offload.h"
	22
	23	static int ipv6_gso_pull_exthdrs(struct sk_buff *skb, int proto)
	24	{
	25	const struct net_offload *ops = NULL;
	26
	27	for (;;) {
	28	struct ipv6_opt_hdr *opth;
	29	int len;
	30
	31	if (proto != NEXTHDR_HOP) {
	32	ops = rcu_dereference(inet6_offloads[proto]);
	33
	34	if (unlikely(!ops))
	35	break;
	36
	37	if (!(ops->flags & INET6_PROTO_GSO_EXTHDR))
	38	break;
	39	}
	40
	41	if (unlikely(!pskb_may_pull(skb, 8)))
	42	break;
	43
	44	opth = (void *)skb->data;
	45	len = ipv6_optlen(opth);
	46
	47	if (unlikely(!pskb_may_pull(skb, len)))
	48	break;
	49
fc6fb41c	50	opth = (void *)skb->data;
d1da932e VY	51	proto = opth->nexthdr;
	52	__skb_pull(skb, len);
	53	}
	54
	55	return proto;
	56	}
	57
d1da932e VY	58	static struct sk_buff ipv6_gso_segment(struct sk_buff skb,
	59	netdev_features_t features)
	60	{
	61	struct sk_buff *segs = ERR_PTR(-EINVAL);
	62	struct ipv6hdr *ipv6h;
	63	const struct net_offload *ops;
	64	int proto;
	65	struct frag_hdr *fptr;
	66	unsigned int unfrag_ip6hlen;
802ab55a	67	unsigned int payload_len;
d1da932e VY	68	u8 *prevhdr;
d1da932e VY	69	int offset = 0;
91a48a2e	70	bool encap, udpfrag;
d3e5e006	71	int nhoff;
07b26c94	72	bool gso_partial;
d1da932e	73
d3e5e006 ED	74	skb_reset_network_header(skb);
d3e5e006 ED	75	nhoff = skb_network_header(skb) - skb_mac_header(skb);
d1da932e VY	76	if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h))))
	77	goto out;
	78
91a48a2e HFS	79	encap = SKB_GSO_CB(skb)->encap_level > 0;
91a48a2e HFS	80	if (encap)
1e16aa3d	81	features &= skb->dev->hw_enc_features;
d3e5e006 ED	82	SKB_GSO_CB(skb)->encap_level += sizeof(*ipv6h);
d3e5e006 ED	83
d1da932e VY	84	ipv6h = ipv6_hdr(skb);
	85	__skb_pull(skb, sizeof(*ipv6h));
	86	segs = ERR_PTR(-EPROTONOSUPPORT);
	87
	88	proto = ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr);
b917eb15	89
91a48a2e	90	if (skb->encapsulation &&
7e13318d	91	skb_shinfo(skb)->gso_type & (SKB_GSO_IPXIP4 \| SKB_GSO_IPXIP6))
91a48a2e HFS	92	udpfrag = proto == IPPROTO_UDP && encap;
	93	else
	94	udpfrag = proto == IPPROTO_UDP && !skb->encapsulation;
	95
d1da932e	96	ops = rcu_dereference(inet6_offloads[proto]);
f191a1d1	97	if (likely(ops && ops->callbacks.gso_segment)) {
d1da932e	98	skb_reset_transport_header(skb);
f191a1d1	99	segs = ops->callbacks.gso_segment(skb, features);
d1da932e	100	}
d1da932e	101
6b6ebb6b	102	if (IS_ERR_OR_NULL(segs))
d1da932e VY	103	goto out;
d1da932e VY	104
07b26c94 SK	105	gso_partial = !!(skb_shinfo(segs)->gso_type & SKB_GSO_PARTIAL);
07b26c94 SK	106
d1da932e	107	for (skb = segs; skb; skb = skb->next) {
d3e5e006	108	ipv6h = (struct ipv6hdr *)(skb_mac_header(skb) + nhoff);
07b26c94	109	if (gso_partial)
802ab55a AD	110	payload_len = skb_shinfo(skb)->gso_size +
	111	SKB_GSO_CB(skb)->data_offset +
	112	skb->head - (unsigned char *)(ipv6h + 1);
	113	else
	114	payload_len = skb->len - nhoff - sizeof(*ipv6h);
	115	ipv6h->payload_len = htons(payload_len);
d3e5e006 ED	116	skb->network_header = (u8 *)ipv6h - skb->head;
d3e5e006 ED	117
91a48a2e	118	if (udpfrag) {
d1da932e	119	unfrag_ip6hlen = ip6_find_1stfragopt(skb, &prevhdr);
d3e5e006	120	fptr = (struct frag_hdr )((u8 )ipv6h + unfrag_ip6hlen);
d1da932e	121	fptr->frag_off = htons(offset);
53b24b8f	122	if (skb->next)
d1da932e VY	123	fptr->frag_off \|= htons(IP6_MF);
	124	offset += (ntohs(ipv6h->payload_len) -
	125	sizeof(struct frag_hdr));
	126	}
91a48a2e HFS	127	if (encap)
91a48a2e HFS	128	skb_reset_inner_headers(skb);
d1da932e VY	129	}
	130
	131	out:
	132	return segs;
	133	}
	134
299603e8 JC	135	/* Return the total length of all the extension hdrs, following the same
	136	* logic in ipv6_gso_pull_exthdrs() when parsing ext-hdrs.
	137	*/
	138	static int ipv6_exthdrs_len(struct ipv6hdr *iph,
	139	const struct net_offload **opps)
	140	{
810c23a3 JC	141	struct ipv6_opt_hdr opth = (void )iph;
810c23a3 JC	142	int len = 0, proto, optlen = sizeof(*iph);
299603e8 JC	143
	144	proto = iph->nexthdr;
	145	for (;;) {
	146	if (proto != NEXTHDR_HOP) {
	147	*opps = rcu_dereference(inet6_offloads[proto]);
	148	if (unlikely(!(*opps)))
	149	break;
	150	if (!((*opps)->flags & INET6_PROTO_GSO_EXTHDR))
	151	break;
	152	}
810c23a3 JC	153	opth = (void *)opth + optlen;
810c23a3 JC	154	optlen = ipv6_optlen(opth);
299603e8 JC	155	len += optlen;
	156	proto = opth->nexthdr;
	157	}
	158	return len;
	159	}
	160
d1da932e VY	161	static struct sk_buff ipv6_gro_receive(struct sk_buff head,
	162	struct sk_buff *skb)
	163	{
	164	const struct net_offload *ops;
	165	struct sk_buff **pp = NULL;
	166	struct sk_buff *p;
	167	struct ipv6hdr *iph;
	168	unsigned int nlen;
	169	unsigned int hlen;
	170	unsigned int off;
bf5a755f	171	u16 flush = 1;
d1da932e	172	int proto;
d1da932e VY	173
	174	off = skb_gro_offset(skb);
	175	hlen = off + sizeof(*iph);
	176	iph = skb_gro_header_fast(skb, off);
	177	if (skb_gro_header_hard(skb, hlen)) {
	178	iph = skb_gro_header_slow(skb, hlen, off);
	179	if (unlikely(!iph))
	180	goto out;
	181	}
	182
299603e8	183	skb_set_network_header(skb, off);
d1da932e VY	184	skb_gro_pull(skb, sizeof(*iph));
	185	skb_set_transport_header(skb, skb_gro_offset(skb));
	186
	187	flush += ntohs(iph->payload_len) != skb_gro_len(skb);
	188
	189	rcu_read_lock();
	190	proto = iph->nexthdr;
	191	ops = rcu_dereference(inet6_offloads[proto]);
f191a1d1	192	if (!ops \|\| !ops->callbacks.gro_receive) {
d1da932e VY	193	__pskb_pull(skb, skb_gro_offset(skb));
	194	proto = ipv6_gso_pull_exthdrs(skb, proto);
	195	skb_gro_pull(skb, -skb_transport_offset(skb));
	196	skb_reset_transport_header(skb);
	197	__skb_push(skb, skb_gro_offset(skb));
	198
	199	ops = rcu_dereference(inet6_offloads[proto]);
f191a1d1	200	if (!ops \|\| !ops->callbacks.gro_receive)
d1da932e VY	201	goto out_unlock;
	202
	203	iph = ipv6_hdr(skb);
	204	}
	205
	206	NAPI_GRO_CB(skb)->proto = proto;
	207
	208	flush--;
	209	nlen = skb_network_header_len(skb);
	210
	211	for (p = *head; p; p = p->next) {
	212	const struct ipv6hdr *iph2;
	213	__be32 first_word; /* <Version:4><Traffic_Class:8><Flow_Label:20> */
	214
	215	if (!NAPI_GRO_CB(p)->same_flow)
	216	continue;
	217
299603e8	218	iph2 = (struct ipv6hdr *)(p->data + off);
67ba4152	219	first_word = (__be32 )iph ^ (__be32 )iph2;
d1da932e	220
299603e8 JC	221	/* All fields must match except length and Traffic Class.
	222	* XXX skbs on the gro_list have all been parsed and pulled
	223	* already so we don't need to compare nlen
	224	* (nlen != (sizeof(*iph2) + ipv6_exthdrs_len(iph2, &ops)))
	225	* memcmp() alone below is suffcient, right?
	226	*/
	227	if ((first_word & htonl(0xF00FFFFF)) \|\|
d1da932e VY	228	memcmp(&iph->nexthdr, &iph2->nexthdr,
	229	nlen - offsetof(struct ipv6hdr, nexthdr))) {
	230	NAPI_GRO_CB(p)->same_flow = 0;
	231	continue;
	232	}
	233	/* flush if Traffic Class fields are different */
	234	NAPI_GRO_CB(p)->flush \|= !!(first_word & htonl(0x0FF00000));
	235	NAPI_GRO_CB(p)->flush \|= flush;
03d56daa	236
1530545e AD	237	/* If the previous IP ID value was based on an atomic
	238	* datagram we can overwrite the value and ignore it.
	239	*/
	240	if (NAPI_GRO_CB(skb)->is_atomic)
	241	NAPI_GRO_CB(p)->flush_id = 0;
d1da932e VY	242	}
d1da932e VY	243
1530545e	244	NAPI_GRO_CB(skb)->is_atomic = true;
d1da932e VY	245	NAPI_GRO_CB(skb)->flush \|= flush;
d1da932e VY	246
4de462ab	247	skb_gro_postpull_rcsum(skb, iph, nlen);
d1da932e	248
fcd91dd4	249	pp = call_gro_receive(ops->callbacks.gro_receive, head, skb);
d1da932e	250
d1da932e VY	251	out_unlock:
	252	rcu_read_unlock();
	253
	254	out:
	255	NAPI_GRO_CB(skb)->flush \|= flush;
	256
	257	return pp;
	258	}
	259
815d22e5 TH	260	static struct sk_buff sit_ip6ip6_gro_receive(struct sk_buff head,
815d22e5 TH	261	struct sk_buff *skb)
fac8e0f5	262	{
815d22e5 TH	263	/* Common GRO receive for SIT and IP6IP6 */
815d22e5 TH	264
fac8e0f5 JG	265	if (NAPI_GRO_CB(skb)->encap_mark) {
	266	NAPI_GRO_CB(skb)->flush = 1;
	267	return NULL;
	268	}
	269
	270	NAPI_GRO_CB(skb)->encap_mark = 1;
	271
	272	return ipv6_gro_receive(head, skb);
	273	}
	274
b8921ca8 TH	275	static struct sk_buff ip4ip6_gro_receive(struct sk_buff head,
	276	struct sk_buff *skb)
	277	{
	278	/* Common GRO receive for SIT and IP6IP6 */
	279
	280	if (NAPI_GRO_CB(skb)->encap_mark) {
	281	NAPI_GRO_CB(skb)->flush = 1;
	282	return NULL;
	283	}
	284
	285	NAPI_GRO_CB(skb)->encap_mark = 1;
	286
	287	return inet_gro_receive(head, skb);
	288	}
	289
299603e8	290	static int ipv6_gro_complete(struct sk_buff *skb, int nhoff)
d1da932e VY	291	{
d1da932e VY	292	const struct net_offload *ops;
299603e8	293	struct ipv6hdr iph = (struct ipv6hdr )(skb->data + nhoff);
d1da932e VY	294	int err = -ENOSYS;
d1da932e VY	295
feec0cb3 ED	296	if (skb->encapsulation)
	297	skb_set_inner_network_header(skb, nhoff);
	298
299603e8	299	iph->payload_len = htons(skb->len - nhoff - sizeof(*iph));
d1da932e VY	300
d1da932e VY	301	rcu_read_lock();
299603e8 JC	302
299603e8 JC	303	nhoff += sizeof(*iph) + ipv6_exthdrs_len(iph, &ops);
f191a1d1	304	if (WARN_ON(!ops \|\| !ops->callbacks.gro_complete))
d1da932e VY	305	goto out_unlock;
d1da932e VY	306
299603e8	307	err = ops->callbacks.gro_complete(skb, nhoff);
d1da932e VY	308
	309	out_unlock:
	310	rcu_read_unlock();
	311
	312	return err;
	313	}
	314
feec0cb3 ED	315	static int sit_gro_complete(struct sk_buff *skb, int nhoff)
	316	{
	317	skb->encapsulation = 1;
7e13318d	318	skb_shinfo(skb)->gso_type \|= SKB_GSO_IPXIP4;
feec0cb3 ED	319	return ipv6_gro_complete(skb, nhoff);
	320	}
	321
815d22e5 TH	322	static int ip6ip6_gro_complete(struct sk_buff *skb, int nhoff)
	323	{
	324	skb->encapsulation = 1;
	325	skb_shinfo(skb)->gso_type \|= SKB_GSO_IPXIP6;
	326	return ipv6_gro_complete(skb, nhoff);
	327	}
	328
b8921ca8 TH	329	static int ip4ip6_gro_complete(struct sk_buff *skb, int nhoff)
	330	{
	331	skb->encapsulation = 1;
	332	skb_shinfo(skb)->gso_type \|= SKB_GSO_IPXIP6;
	333	return inet_gro_complete(skb, nhoff);
	334	}
	335
d1da932e VY	336	static struct packet_offload ipv6_packet_offload __read_mostly = {
d1da932e VY	337	.type = cpu_to_be16(ETH_P_IPV6),
f191a1d1	338	.callbacks = {
f191a1d1 VY	339	.gso_segment = ipv6_gso_segment,
	340	.gro_receive = ipv6_gro_receive,
	341	.gro_complete = ipv6_gro_complete,
	342	},
d1da932e VY	343	};
d1da932e VY	344
61c1db7f ED	345	static const struct net_offload sit_offload = {
61c1db7f ED	346	.callbacks = {
61c1db7f	347	.gso_segment = ipv6_gso_segment,
815d22e5	348	.gro_receive = sit_ip6ip6_gro_receive,
feec0cb3	349	.gro_complete = sit_gro_complete,
61c1db7f ED	350	},
	351	};
	352
b8921ca8 TH	353	static const struct net_offload ip4ip6_offload = {
	354	.callbacks = {
	355	.gso_segment = inet_gso_segment,
	356	.gro_receive = ip4ip6_gro_receive,
	357	.gro_complete = ip4ip6_gro_complete,
	358	},
	359	};
	360
815d22e5 TH	361	static const struct net_offload ip6ip6_offload = {
	362	.callbacks = {
	363	.gso_segment = ipv6_gso_segment,
	364	.gro_receive = sit_ip6ip6_gro_receive,
	365	.gro_complete = ip6ip6_gro_complete,
	366	},
	367	};
c6b641a4	368	static int __init ipv6_offload_init(void)
d1da932e	369	{
c6b641a4 VY	370
	371	if (tcpv6_offload_init() < 0)
	372	pr_crit("%s: Cannot add TCP protocol offload\n", __func__);
c6b641a4 VY	373	if (ipv6_exthdrs_offload_init() < 0)
	374	pr_crit("%s: Cannot add EXTHDRS protocol offload\n", __func__);
	375
d1da932e	376	dev_add_offload(&ipv6_packet_offload);
61c1db7f ED	377
61c1db7f ED	378	inet_add_offload(&sit_offload, IPPROTO_IPV6);
815d22e5	379	inet6_add_offload(&ip6ip6_offload, IPPROTO_IPV6);
b8921ca8	380	inet6_add_offload(&ip4ip6_offload, IPPROTO_IPIP);
61c1db7f	381
c6b641a4	382	return 0;
d1da932e VY	383	}
d1da932e VY	384
c6b641a4	385	fs_initcall(ipv6_offload_init);