[linux.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 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 && skb_is_gso(skb))
			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) {
			int err = ip6_find_1stfragopt(skb, &prevhdr);
			if (err < 0) {
				kfree_skb_list(segs);
				return ERR_PTR(err);
			}
			fptr = (struct frag_hdr *)((u8 *)ipv6h + err);
			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));
		skb_gro_frag0_invalidate(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:
	skb_gro_flush_final(skb, pp, 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_protocol(skb, cpu_to_be16(ETH_P_IPV6));
		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;
802ab55a	66	unsigned int payload_len;
d1da932e VY	67	u8 *prevhdr;
d1da932e VY	68	int offset = 0;
91a48a2e	69	bool encap, udpfrag;
d3e5e006	70	int nhoff;
07b26c94	71	bool gso_partial;
d1da932e	72
d3e5e006 ED	73	skb_reset_network_header(skb);
d3e5e006 ED	74	nhoff = skb_network_header(skb) - skb_mac_header(skb);
d1da932e VY	75	if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h))))
	76	goto out;
	77
91a48a2e HFS	78	encap = SKB_GSO_CB(skb)->encap_level > 0;
91a48a2e HFS	79	if (encap)
1e16aa3d	80	features &= skb->dev->hw_enc_features;
d3e5e006 ED	81	SKB_GSO_CB(skb)->encap_level += sizeof(*ipv6h);
d3e5e006 ED	82
d1da932e VY	83	ipv6h = ipv6_hdr(skb);
	84	__skb_pull(skb, sizeof(*ipv6h));
	85	segs = ERR_PTR(-EPROTONOSUPPORT);
	86
	87	proto = ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr);
b917eb15	88
91a48a2e	89	if (skb->encapsulation &&
7e13318d	90	skb_shinfo(skb)->gso_type & (SKB_GSO_IPXIP4 \| SKB_GSO_IPXIP6))
91a48a2e HFS	91	udpfrag = proto == IPPROTO_UDP && encap;
	92	else
	93	udpfrag = proto == IPPROTO_UDP && !skb->encapsulation;
	94
d1da932e	95	ops = rcu_dereference(inet6_offloads[proto]);
f191a1d1	96	if (likely(ops && ops->callbacks.gso_segment)) {
d1da932e	97	skb_reset_transport_header(skb);
f191a1d1	98	segs = ops->callbacks.gso_segment(skb, features);
d1da932e	99	}
d1da932e	100
6b6ebb6b	101	if (IS_ERR_OR_NULL(segs))
d1da932e VY	102	goto out;
d1da932e VY	103
07b26c94 SK	104	gso_partial = !!(skb_shinfo(segs)->gso_type & SKB_GSO_PARTIAL);
07b26c94 SK	105
d1da932e	106	for (skb = segs; skb; skb = skb->next) {
d3e5e006	107	ipv6h = (struct ipv6hdr *)(skb_mac_header(skb) + nhoff);
3d0241d5	108	if (gso_partial && skb_is_gso(skb))
802ab55a AD	109	payload_len = skb_shinfo(skb)->gso_size +
	110	SKB_GSO_CB(skb)->data_offset +
	111	skb->head - (unsigned char *)(ipv6h + 1);
	112	else
	113	payload_len = skb->len - nhoff - sizeof(*ipv6h);
	114	ipv6h->payload_len = htons(payload_len);
d3e5e006 ED	115	skb->network_header = (u8 *)ipv6h - skb->head;
d3e5e006 ED	116
91a48a2e	117	if (udpfrag) {
7dd7eb95	118	int err = ip6_find_1stfragopt(skb, &prevhdr);
e3e86b51 DM	119	if (err < 0) {
e3e86b51 DM	120	kfree_skb_list(segs);
7dd7eb95	121	return ERR_PTR(err);
e3e86b51	122	}
7dd7eb95	123	fptr = (struct frag_hdr )((u8 )ipv6h + err);
d1da932e	124	fptr->frag_off = htons(offset);
53b24b8f	125	if (skb->next)
d1da932e VY	126	fptr->frag_off \|= htons(IP6_MF);
	127	offset += (ntohs(ipv6h->payload_len) -
	128	sizeof(struct frag_hdr));
	129	}
91a48a2e HFS	130	if (encap)
91a48a2e HFS	131	skb_reset_inner_headers(skb);
d1da932e VY	132	}
	133
	134	out:
	135	return segs;
	136	}
	137
299603e8 JC	138	/* Return the total length of all the extension hdrs, following the same
	139	* logic in ipv6_gso_pull_exthdrs() when parsing ext-hdrs.
	140	*/
	141	static int ipv6_exthdrs_len(struct ipv6hdr *iph,
	142	const struct net_offload **opps)
	143	{
810c23a3 JC	144	struct ipv6_opt_hdr opth = (void )iph;
810c23a3 JC	145	int len = 0, proto, optlen = sizeof(*iph);
299603e8 JC	146
	147	proto = iph->nexthdr;
	148	for (;;) {
	149	if (proto != NEXTHDR_HOP) {
	150	*opps = rcu_dereference(inet6_offloads[proto]);
	151	if (unlikely(!(*opps)))
	152	break;
	153	if (!((*opps)->flags & INET6_PROTO_GSO_EXTHDR))
	154	break;
	155	}
810c23a3 JC	156	opth = (void *)opth + optlen;
810c23a3 JC	157	optlen = ipv6_optlen(opth);
299603e8 JC	158	len += optlen;
	159	proto = opth->nexthdr;
	160	}
	161	return len;
	162	}
	163
d1da932e VY	164	static struct sk_buff ipv6_gro_receive(struct sk_buff head,
	165	struct sk_buff *skb)
	166	{
	167	const struct net_offload *ops;
	168	struct sk_buff **pp = NULL;
	169	struct sk_buff *p;
	170	struct ipv6hdr *iph;
	171	unsigned int nlen;
	172	unsigned int hlen;
	173	unsigned int off;
bf5a755f	174	u16 flush = 1;
d1da932e	175	int proto;
d1da932e VY	176
	177	off = skb_gro_offset(skb);
	178	hlen = off + sizeof(*iph);
	179	iph = skb_gro_header_fast(skb, off);
	180	if (skb_gro_header_hard(skb, hlen)) {
	181	iph = skb_gro_header_slow(skb, hlen, off);
	182	if (unlikely(!iph))
	183	goto out;
	184	}
	185
299603e8	186	skb_set_network_header(skb, off);
d1da932e VY	187	skb_gro_pull(skb, sizeof(*iph));
	188	skb_set_transport_header(skb, skb_gro_offset(skb));
	189
	190	flush += ntohs(iph->payload_len) != skb_gro_len(skb);
	191
	192	rcu_read_lock();
	193	proto = iph->nexthdr;
	194	ops = rcu_dereference(inet6_offloads[proto]);
f191a1d1	195	if (!ops \|\| !ops->callbacks.gro_receive) {
d1da932e	196	__pskb_pull(skb, skb_gro_offset(skb));
57ea52a8	197	skb_gro_frag0_invalidate(skb);
d1da932e VY	198	proto = ipv6_gso_pull_exthdrs(skb, proto);
	199	skb_gro_pull(skb, -skb_transport_offset(skb));
	200	skb_reset_transport_header(skb);
	201	__skb_push(skb, skb_gro_offset(skb));
	202
	203	ops = rcu_dereference(inet6_offloads[proto]);
f191a1d1	204	if (!ops \|\| !ops->callbacks.gro_receive)
d1da932e VY	205	goto out_unlock;
	206
	207	iph = ipv6_hdr(skb);
	208	}
	209
	210	NAPI_GRO_CB(skb)->proto = proto;
	211
	212	flush--;
	213	nlen = skb_network_header_len(skb);
	214
	215	for (p = *head; p; p = p->next) {
	216	const struct ipv6hdr *iph2;
	217	__be32 first_word; /* <Version:4><Traffic_Class:8><Flow_Label:20> */
	218
	219	if (!NAPI_GRO_CB(p)->same_flow)
	220	continue;
	221
299603e8	222	iph2 = (struct ipv6hdr *)(p->data + off);
67ba4152	223	first_word = (__be32 )iph ^ (__be32 )iph2;
d1da932e	224
299603e8 JC	225	/* All fields must match except length and Traffic Class.
	226	* XXX skbs on the gro_list have all been parsed and pulled
	227	* already so we don't need to compare nlen
	228	* (nlen != (sizeof(*iph2) + ipv6_exthdrs_len(iph2, &ops)))
	229	* memcmp() alone below is suffcient, right?
	230	*/
	231	if ((first_word & htonl(0xF00FFFFF)) \|\|
d1da932e VY	232	memcmp(&iph->nexthdr, &iph2->nexthdr,
	233	nlen - offsetof(struct ipv6hdr, nexthdr))) {
	234	NAPI_GRO_CB(p)->same_flow = 0;
	235	continue;
	236	}
	237	/* flush if Traffic Class fields are different */
	238	NAPI_GRO_CB(p)->flush \|= !!(first_word & htonl(0x0FF00000));
	239	NAPI_GRO_CB(p)->flush \|= flush;
03d56daa	240
1530545e AD	241	/* If the previous IP ID value was based on an atomic
	242	* datagram we can overwrite the value and ignore it.
	243	*/
	244	if (NAPI_GRO_CB(skb)->is_atomic)
	245	NAPI_GRO_CB(p)->flush_id = 0;
d1da932e VY	246	}
d1da932e VY	247
1530545e	248	NAPI_GRO_CB(skb)->is_atomic = true;
d1da932e VY	249	NAPI_GRO_CB(skb)->flush \|= flush;
d1da932e VY	250
4de462ab	251	skb_gro_postpull_rcsum(skb, iph, nlen);
d1da932e	252
fcd91dd4	253	pp = call_gro_receive(ops->callbacks.gro_receive, head, skb);
d1da932e	254
d1da932e VY	255	out_unlock:
	256	rcu_read_unlock();
	257
	258	out:
5f114163	259	skb_gro_flush_final(skb, pp, flush);
d1da932e VY	260
	261	return pp;
	262	}
	263
815d22e5 TH	264	static struct sk_buff sit_ip6ip6_gro_receive(struct sk_buff head,
815d22e5 TH	265	struct sk_buff *skb)
fac8e0f5	266	{
815d22e5 TH	267	/* Common GRO receive for SIT and IP6IP6 */
815d22e5 TH	268
fac8e0f5 JG	269	if (NAPI_GRO_CB(skb)->encap_mark) {
	270	NAPI_GRO_CB(skb)->flush = 1;
	271	return NULL;
	272	}
	273
	274	NAPI_GRO_CB(skb)->encap_mark = 1;
	275
	276	return ipv6_gro_receive(head, skb);
	277	}
	278
b8921ca8 TH	279	static struct sk_buff ip4ip6_gro_receive(struct sk_buff head,
	280	struct sk_buff *skb)
	281	{
	282	/* Common GRO receive for SIT and IP6IP6 */
	283
	284	if (NAPI_GRO_CB(skb)->encap_mark) {
	285	NAPI_GRO_CB(skb)->flush = 1;
	286	return NULL;
	287	}
	288
	289	NAPI_GRO_CB(skb)->encap_mark = 1;
	290
	291	return inet_gro_receive(head, skb);
	292	}
	293
299603e8	294	static int ipv6_gro_complete(struct sk_buff *skb, int nhoff)
d1da932e VY	295	{
d1da932e VY	296	const struct net_offload *ops;
299603e8	297	struct ipv6hdr iph = (struct ipv6hdr )(skb->data + nhoff);
d1da932e VY	298	int err = -ENOSYS;
d1da932e VY	299
294acf1c PA	300	if (skb->encapsulation) {
294acf1c PA	301	skb_set_inner_protocol(skb, cpu_to_be16(ETH_P_IPV6));
feec0cb3	302	skb_set_inner_network_header(skb, nhoff);
294acf1c	303	}
feec0cb3	304
299603e8	305	iph->payload_len = htons(skb->len - nhoff - sizeof(*iph));
d1da932e VY	306
d1da932e VY	307	rcu_read_lock();
299603e8 JC	308
299603e8 JC	309	nhoff += sizeof(*iph) + ipv6_exthdrs_len(iph, &ops);
f191a1d1	310	if (WARN_ON(!ops \|\| !ops->callbacks.gro_complete))
d1da932e VY	311	goto out_unlock;
d1da932e VY	312
299603e8	313	err = ops->callbacks.gro_complete(skb, nhoff);
d1da932e VY	314
	315	out_unlock:
	316	rcu_read_unlock();
	317
	318	return err;
	319	}
	320
feec0cb3 ED	321	static int sit_gro_complete(struct sk_buff *skb, int nhoff)
	322	{
	323	skb->encapsulation = 1;
7e13318d	324	skb_shinfo(skb)->gso_type \|= SKB_GSO_IPXIP4;
feec0cb3 ED	325	return ipv6_gro_complete(skb, nhoff);
	326	}
	327
815d22e5 TH	328	static int ip6ip6_gro_complete(struct sk_buff *skb, int nhoff)
	329	{
	330	skb->encapsulation = 1;
	331	skb_shinfo(skb)->gso_type \|= SKB_GSO_IPXIP6;
	332	return ipv6_gro_complete(skb, nhoff);
	333	}
	334
b8921ca8 TH	335	static int ip4ip6_gro_complete(struct sk_buff *skb, int nhoff)
	336	{
	337	skb->encapsulation = 1;
	338	skb_shinfo(skb)->gso_type \|= SKB_GSO_IPXIP6;
	339	return inet_gro_complete(skb, nhoff);
	340	}
	341
d1da932e VY	342	static struct packet_offload ipv6_packet_offload __read_mostly = {
d1da932e VY	343	.type = cpu_to_be16(ETH_P_IPV6),
f191a1d1	344	.callbacks = {
f191a1d1 VY	345	.gso_segment = ipv6_gso_segment,
	346	.gro_receive = ipv6_gro_receive,
	347	.gro_complete = ipv6_gro_complete,
	348	},
d1da932e VY	349	};
d1da932e VY	350
61c1db7f ED	351	static const struct net_offload sit_offload = {
61c1db7f ED	352	.callbacks = {
61c1db7f	353	.gso_segment = ipv6_gso_segment,
815d22e5	354	.gro_receive = sit_ip6ip6_gro_receive,
feec0cb3	355	.gro_complete = sit_gro_complete,
61c1db7f ED	356	},
	357	};
	358
b8921ca8 TH	359	static const struct net_offload ip4ip6_offload = {
	360	.callbacks = {
	361	.gso_segment = inet_gso_segment,
	362	.gro_receive = ip4ip6_gro_receive,
	363	.gro_complete = ip4ip6_gro_complete,
	364	},
	365	};
	366
815d22e5 TH	367	static const struct net_offload ip6ip6_offload = {
	368	.callbacks = {
	369	.gso_segment = ipv6_gso_segment,
	370	.gro_receive = sit_ip6ip6_gro_receive,
	371	.gro_complete = ip6ip6_gro_complete,
	372	},
	373	};
c6b641a4	374	static int __init ipv6_offload_init(void)
d1da932e	375	{
c6b641a4 VY	376
	377	if (tcpv6_offload_init() < 0)
	378	pr_crit("%s: Cannot add TCP protocol offload\n", __func__);
c6b641a4 VY	379	if (ipv6_exthdrs_offload_init() < 0)
	380	pr_crit("%s: Cannot add EXTHDRS protocol offload\n", __func__);
	381
d1da932e	382	dev_add_offload(&ipv6_packet_offload);
61c1db7f ED	383
61c1db7f ED	384	inet_add_offload(&sit_offload, IPPROTO_IPV6);
815d22e5	385	inet6_add_offload(&ip6ip6_offload, IPPROTO_IPV6);
b8921ca8	386	inet6_add_offload(&ip4ip6_offload, IPPROTO_IPIP);
61c1db7f	387
c6b641a4	388	return 0;
d1da932e VY	389	}
d1da932e VY	390
c6b641a4	391	fs_initcall(ipv6_offload_init);