[linux-2.6-block.git] / net / ipv6 / ip6_offload.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *	IPV6 GSO/GRO offload support
 *	Linux INET6 implementation
 */

#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"

/* All GRO functions are always builtin, except UDP over ipv6, which lays in
 * ipv6 module, as it depends on UDPv6 lookup function, so we need special care
 * when ipv6 is built as a module
 */
#if IS_BUILTIN(CONFIG_IPV6)
#define INDIRECT_CALL_L4(f, f2, f1, ...) INDIRECT_CALL_2(f, f2, f1, __VA_ARGS__)
#else
#define INDIRECT_CALL_L4(f, f2, f1, ...) INDIRECT_CALL_1(f, f2, __VA_ARGS__)
#endif

#define indirect_call_gro_receive_l4(f2, f1, cb, head, skb)	\
({								\
	unlikely(gro_recursion_inc_test(skb)) ?			\
		NAPI_GRO_CB(skb)->flush |= 1, NULL :		\
		INDIRECT_CALL_L4(cb, f2, f1, head, skb);	\
})

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 &&
			  (skb_shinfo(skb)->gso_type & SKB_GSO_UDP);
	else
		udpfrag = proto == IPPROTO_UDP && !skb->encapsulation &&
			  (skb_shinfo(skb)->gso_type & SKB_GSO_UDP);

	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;
		skb_reset_mac_len(skb);

		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;
}

INDIRECT_CALLABLE_DECLARE(struct sk_buff *tcp6_gro_receive(struct list_head *,
							   struct sk_buff *));
INDIRECT_CALLABLE_DECLARE(struct sk_buff *udp6_gro_receive(struct list_head *,
							   struct sk_buff *));
INDIRECT_CALLABLE_SCOPE struct sk_buff *ipv6_gro_receive(struct list_head *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);

	list_for_each_entry(p, head, list) {
		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 sufficient, right?
		 */
		 if ((first_word & htonl(0xF00FFFFF)) ||
		    !ipv6_addr_equal(&iph->saddr, &iph2->saddr) ||
		    !ipv6_addr_equal(&iph->daddr, &iph2->daddr) ||
		    *(u16 *)&iph->nexthdr != *(u16 *)&iph2->nexthdr) {
not_same_flow:
			NAPI_GRO_CB(p)->same_flow = 0;
			continue;
		}
		if (unlikely(nlen > sizeof(struct ipv6hdr))) {
			if (memcmp(iph + 1, iph2 + 1,
				   nlen - sizeof(struct ipv6hdr)))
				goto not_same_flow;
		}
		/* 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 = indirect_call_gro_receive_l4(tcp6_gro_receive, udp6_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 list_head *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 list_head *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);
}

INDIRECT_CALLABLE_DECLARE(int tcp6_gro_complete(struct sk_buff *, int));
INDIRECT_CALLABLE_DECLARE(int udp6_gro_complete(struct sk_buff *, int));
INDIRECT_CALLABLE_SCOPE 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 = INDIRECT_CALL_L4(ops->callbacks.gro_complete, tcp6_gro_complete,
			       udp6_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 struct sk_buff *sit_gso_segment(struct sk_buff *skb,
				       netdev_features_t features)
{
	if (!(skb_shinfo(skb)->gso_type & SKB_GSO_IPXIP4))
		return ERR_PTR(-EINVAL);

	return ipv6_gso_segment(skb, features);
}

static struct sk_buff *ip4ip6_gso_segment(struct sk_buff *skb,
					  netdev_features_t features)
{
	if (!(skb_shinfo(skb)->gso_type & SKB_GSO_IPXIP6))
		return ERR_PTR(-EINVAL);

	return inet_gso_segment(skb, features);
}

static struct sk_buff *ip6ip6_gso_segment(struct sk_buff *skb,
					  netdev_features_t features)
{
	if (!(skb_shinfo(skb)->gso_type & SKB_GSO_IPXIP6))
		return ERR_PTR(-EINVAL);

	return ipv6_gso_segment(skb, features);
}

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

static const struct net_offload ip4ip6_offload = {
	.callbacks = {
		.gso_segment	= ip4ip6_gso_segment,
		.gro_receive    = ip4ip6_gro_receive,
		.gro_complete   = ip4ip6_gro_complete,
	},
};

static const struct net_offload ip6ip6_offload = {
	.callbacks = {
		.gso_segment	= ip6ip6_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
2874c5fd	1	// SPDX-License-Identifier: GPL-2.0-or-later
d1da932e VY	2	/*
	3	* IPV6 GSO/GRO offload support
	4	* Linux INET6 implementation
d1da932e VY	5	*/
	6
	7	#include <linux/kernel.h>
	8	#include <linux/socket.h>
	9	#include <linux/netdevice.h>
	10	#include <linux/skbuff.h>
c6b641a4	11	#include <linux/printk.h>
d1da932e VY	12
	13	#include <net/protocol.h>
	14	#include <net/ipv6.h>
b8921ca8	15	#include <net/inet_common.h>
d1da932e VY	16
	17	#include "ip6_offload.h"
	18
028e0a47 PA	19	/* All GRO functions are always builtin, except UDP over ipv6, which lays in
	20	* ipv6 module, as it depends on UDPv6 lookup function, so we need special care
	21	* when ipv6 is built as a module
	22	*/
	23	#if IS_BUILTIN(CONFIG_IPV6)
	24	#define INDIRECT_CALL_L4(f, f2, f1, ...) INDIRECT_CALL_2(f, f2, f1, __VA_ARGS__)
	25	#else
	26	#define INDIRECT_CALL_L4(f, f2, f1, ...) INDIRECT_CALL_1(f, f2, __VA_ARGS__)
	27	#endif
	28
	29	#define indirect_call_gro_receive_l4(f2, f1, cb, head, skb) \
	30	({ \
	31	unlikely(gro_recursion_inc_test(skb)) ? \
	32	NAPI_GRO_CB(skb)->flush \|= 1, NULL : \
	33	INDIRECT_CALL_L4(cb, f2, f1, head, skb); \
	34	})
	35
d1da932e VY	36	static int ipv6_gso_pull_exthdrs(struct sk_buff *skb, int proto)
	37	{
	38	const struct net_offload *ops = NULL;
	39
	40	for (;;) {
	41	struct ipv6_opt_hdr *opth;
	42	int len;
	43
	44	if (proto != NEXTHDR_HOP) {
	45	ops = rcu_dereference(inet6_offloads[proto]);
	46
	47	if (unlikely(!ops))
	48	break;
	49
	50	if (!(ops->flags & INET6_PROTO_GSO_EXTHDR))
	51	break;
	52	}
	53
	54	if (unlikely(!pskb_may_pull(skb, 8)))
	55	break;
	56
	57	opth = (void *)skb->data;
	58	len = ipv6_optlen(opth);
	59
	60	if (unlikely(!pskb_may_pull(skb, len)))
	61	break;
	62
fc6fb41c	63	opth = (void *)skb->data;
d1da932e VY	64	proto = opth->nexthdr;
	65	__skb_pull(skb, len);
	66	}
	67
	68	return proto;
	69	}
	70
d1da932e VY	71	static struct sk_buff ipv6_gso_segment(struct sk_buff skb,
	72	netdev_features_t features)
	73	{
	74	struct sk_buff *segs = ERR_PTR(-EINVAL);
	75	struct ipv6hdr *ipv6h;
	76	const struct net_offload *ops;
	77	int proto;
	78	struct frag_hdr *fptr;
802ab55a	79	unsigned int payload_len;
d1da932e VY	80	u8 *prevhdr;
d1da932e VY	81	int offset = 0;
91a48a2e	82	bool encap, udpfrag;
d3e5e006	83	int nhoff;
07b26c94	84	bool gso_partial;
d1da932e	85
d3e5e006 ED	86	skb_reset_network_header(skb);
d3e5e006 ED	87	nhoff = skb_network_header(skb) - skb_mac_header(skb);
d1da932e VY	88	if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h))))
	89	goto out;
	90
91a48a2e HFS	91	encap = SKB_GSO_CB(skb)->encap_level > 0;
91a48a2e HFS	92	if (encap)
1e16aa3d	93	features &= skb->dev->hw_enc_features;
d3e5e006 ED	94	SKB_GSO_CB(skb)->encap_level += sizeof(*ipv6h);
d3e5e006 ED	95
d1da932e VY	96	ipv6h = ipv6_hdr(skb);
	97	__skb_pull(skb, sizeof(*ipv6h));
	98	segs = ERR_PTR(-EPROTONOSUPPORT);
	99
	100	proto = ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr);
b917eb15	101
91a48a2e	102	if (skb->encapsulation &&
7e13318d	103	skb_shinfo(skb)->gso_type & (SKB_GSO_IPXIP4 \| SKB_GSO_IPXIP6))
ee80d1eb WB	104	udpfrag = proto == IPPROTO_UDP && encap &&
ee80d1eb WB	105	(skb_shinfo(skb)->gso_type & SKB_GSO_UDP);
91a48a2e	106	else
ee80d1eb WB	107	udpfrag = proto == IPPROTO_UDP && !skb->encapsulation &&
ee80d1eb WB	108	(skb_shinfo(skb)->gso_type & SKB_GSO_UDP);
91a48a2e	109
d1da932e	110	ops = rcu_dereference(inet6_offloads[proto]);
f191a1d1	111	if (likely(ops && ops->callbacks.gso_segment)) {
d1da932e	112	skb_reset_transport_header(skb);
f191a1d1	113	segs = ops->callbacks.gso_segment(skb, features);
d1da932e	114	}
d1da932e	115
6b6ebb6b	116	if (IS_ERR_OR_NULL(segs))
d1da932e VY	117	goto out;
d1da932e VY	118
07b26c94 SK	119	gso_partial = !!(skb_shinfo(segs)->gso_type & SKB_GSO_PARTIAL);
07b26c94 SK	120
d1da932e	121	for (skb = segs; skb; skb = skb->next) {
d3e5e006	122	ipv6h = (struct ipv6hdr *)(skb_mac_header(skb) + nhoff);
3d0241d5	123	if (gso_partial && skb_is_gso(skb))
802ab55a AD	124	payload_len = skb_shinfo(skb)->gso_size +
	125	SKB_GSO_CB(skb)->data_offset +
	126	skb->head - (unsigned char *)(ipv6h + 1);
	127	else
	128	payload_len = skb->len - nhoff - sizeof(*ipv6h);
	129	ipv6h->payload_len = htons(payload_len);
d3e5e006	130	skb->network_header = (u8 *)ipv6h - skb->head;
c56cae23	131	skb_reset_mac_len(skb);
d3e5e006	132
91a48a2e	133	if (udpfrag) {
7dd7eb95	134	int err = ip6_find_1stfragopt(skb, &prevhdr);
e3e86b51 DM	135	if (err < 0) {
e3e86b51 DM	136	kfree_skb_list(segs);
7dd7eb95	137	return ERR_PTR(err);
e3e86b51	138	}
7dd7eb95	139	fptr = (struct frag_hdr )((u8 )ipv6h + err);
d1da932e	140	fptr->frag_off = htons(offset);
53b24b8f	141	if (skb->next)
d1da932e VY	142	fptr->frag_off \|= htons(IP6_MF);
	143	offset += (ntohs(ipv6h->payload_len) -
	144	sizeof(struct frag_hdr));
	145	}
91a48a2e HFS	146	if (encap)
91a48a2e HFS	147	skb_reset_inner_headers(skb);
d1da932e VY	148	}
	149
	150	out:
	151	return segs;
	152	}
	153
299603e8 JC	154	/* Return the total length of all the extension hdrs, following the same
	155	* logic in ipv6_gso_pull_exthdrs() when parsing ext-hdrs.
	156	*/
	157	static int ipv6_exthdrs_len(struct ipv6hdr *iph,
	158	const struct net_offload **opps)
	159	{
810c23a3 JC	160	struct ipv6_opt_hdr opth = (void )iph;
810c23a3 JC	161	int len = 0, proto, optlen = sizeof(*iph);
299603e8 JC	162
	163	proto = iph->nexthdr;
	164	for (;;) {
	165	if (proto != NEXTHDR_HOP) {
	166	*opps = rcu_dereference(inet6_offloads[proto]);
	167	if (unlikely(!(*opps)))
	168	break;
	169	if (!((*opps)->flags & INET6_PROTO_GSO_EXTHDR))
	170	break;
	171	}
810c23a3 JC	172	opth = (void *)opth + optlen;
810c23a3 JC	173	optlen = ipv6_optlen(opth);
299603e8 JC	174	len += optlen;
	175	proto = opth->nexthdr;
	176	}
	177	return len;
	178	}
	179
028e0a47 PA	180	INDIRECT_CALLABLE_DECLARE(struct sk_buff tcp6_gro_receive(struct list_head ,
	181	struct sk_buff *));
	182	INDIRECT_CALLABLE_DECLARE(struct sk_buff udp6_gro_receive(struct list_head ,
	183	struct sk_buff *));
aaa5d90b PA	184	INDIRECT_CALLABLE_SCOPE struct sk_buff ipv6_gro_receive(struct list_head head,
aaa5d90b PA	185	struct sk_buff *skb)
d1da932e VY	186	{
d1da932e VY	187	const struct net_offload *ops;
d4546c25	188	struct sk_buff *pp = NULL;
d1da932e VY	189	struct sk_buff *p;
	190	struct ipv6hdr *iph;
	191	unsigned int nlen;
	192	unsigned int hlen;
	193	unsigned int off;
bf5a755f	194	u16 flush = 1;
d1da932e	195	int proto;
d1da932e VY	196
	197	off = skb_gro_offset(skb);
	198	hlen = off + sizeof(*iph);
	199	iph = skb_gro_header_fast(skb, off);
	200	if (skb_gro_header_hard(skb, hlen)) {
	201	iph = skb_gro_header_slow(skb, hlen, off);
	202	if (unlikely(!iph))
	203	goto out;
	204	}
	205
299603e8	206	skb_set_network_header(skb, off);
d1da932e VY	207	skb_gro_pull(skb, sizeof(*iph));
	208	skb_set_transport_header(skb, skb_gro_offset(skb));
	209
	210	flush += ntohs(iph->payload_len) != skb_gro_len(skb);
	211
	212	rcu_read_lock();
	213	proto = iph->nexthdr;
	214	ops = rcu_dereference(inet6_offloads[proto]);
f191a1d1	215	if (!ops \|\| !ops->callbacks.gro_receive) {
d1da932e	216	__pskb_pull(skb, skb_gro_offset(skb));
57ea52a8	217	skb_gro_frag0_invalidate(skb);
d1da932e VY	218	proto = ipv6_gso_pull_exthdrs(skb, proto);
	219	skb_gro_pull(skb, -skb_transport_offset(skb));
	220	skb_reset_transport_header(skb);
	221	__skb_push(skb, skb_gro_offset(skb));
	222
	223	ops = rcu_dereference(inet6_offloads[proto]);
f191a1d1	224	if (!ops \|\| !ops->callbacks.gro_receive)
d1da932e VY	225	goto out_unlock;
	226
	227	iph = ipv6_hdr(skb);
	228	}
	229
	230	NAPI_GRO_CB(skb)->proto = proto;
	231
	232	flush--;
	233	nlen = skb_network_header_len(skb);
	234
d4546c25	235	list_for_each_entry(p, head, list) {
d1da932e VY	236	const struct ipv6hdr *iph2;
	237	__be32 first_word; /* <Version:4><Traffic_Class:8><Flow_Label:20> */
	238
	239	if (!NAPI_GRO_CB(p)->same_flow)
	240	continue;
	241
299603e8	242	iph2 = (struct ipv6hdr *)(p->data + off);
67ba4152	243	first_word = (__be32 )iph ^ (__be32 )iph2;
d1da932e	244
299603e8 JC	245	/* All fields must match except length and Traffic Class.
	246	* XXX skbs on the gro_list have all been parsed and pulled
	247	* already so we don't need to compare nlen
	248	* (nlen != (sizeof(*iph2) + ipv6_exthdrs_len(iph2, &ops)))
0b215b97	249	* memcmp() alone below is sufficient, right?
299603e8 JC	250	*/
299603e8 JC	251	if ((first_word & htonl(0xF00FFFFF)) \|\|
0b215b97 ED	252	!ipv6_addr_equal(&iph->saddr, &iph2->saddr) \|\|
	253	!ipv6_addr_equal(&iph->daddr, &iph2->daddr) \|\|
	254	(u16 )&iph->nexthdr != (u16 )&iph2->nexthdr) {
	255	not_same_flow:
d1da932e VY	256	NAPI_GRO_CB(p)->same_flow = 0;
	257	continue;
	258	}
0b215b97 ED	259	if (unlikely(nlen > sizeof(struct ipv6hdr))) {
	260	if (memcmp(iph + 1, iph2 + 1,
	261	nlen - sizeof(struct ipv6hdr)))
	262	goto not_same_flow;
	263	}
d1da932e VY	264	/* flush if Traffic Class fields are different */
	265	NAPI_GRO_CB(p)->flush \|= !!(first_word & htonl(0x0FF00000));
	266	NAPI_GRO_CB(p)->flush \|= flush;
03d56daa	267
1530545e AD	268	/* If the previous IP ID value was based on an atomic
	269	* datagram we can overwrite the value and ignore it.
	270	*/
	271	if (NAPI_GRO_CB(skb)->is_atomic)
	272	NAPI_GRO_CB(p)->flush_id = 0;
d1da932e VY	273	}
d1da932e VY	274
1530545e	275	NAPI_GRO_CB(skb)->is_atomic = true;
d1da932e VY	276	NAPI_GRO_CB(skb)->flush \|= flush;
d1da932e VY	277
4de462ab	278	skb_gro_postpull_rcsum(skb, iph, nlen);
d1da932e	279
028e0a47 PA	280	pp = indirect_call_gro_receive_l4(tcp6_gro_receive, udp6_gro_receive,
028e0a47 PA	281	ops->callbacks.gro_receive, head, skb);
d1da932e	282
d1da932e VY	283	out_unlock:
	284	rcu_read_unlock();
	285
	286	out:
5f114163	287	skb_gro_flush_final(skb, pp, flush);
d1da932e VY	288
	289	return pp;
	290	}
	291
d4546c25 DM	292	static struct sk_buff sit_ip6ip6_gro_receive(struct list_head head,
d4546c25 DM	293	struct sk_buff *skb)
fac8e0f5	294	{
815d22e5 TH	295	/* Common GRO receive for SIT and IP6IP6 */
815d22e5 TH	296
fac8e0f5 JG	297	if (NAPI_GRO_CB(skb)->encap_mark) {
	298	NAPI_GRO_CB(skb)->flush = 1;
	299	return NULL;
	300	}
	301
	302	NAPI_GRO_CB(skb)->encap_mark = 1;
	303
	304	return ipv6_gro_receive(head, skb);
	305	}
	306
d4546c25 DM	307	static struct sk_buff ip4ip6_gro_receive(struct list_head head,
d4546c25 DM	308	struct sk_buff *skb)
b8921ca8 TH	309	{
	310	/* Common GRO receive for SIT and IP6IP6 */
	311
	312	if (NAPI_GRO_CB(skb)->encap_mark) {
	313	NAPI_GRO_CB(skb)->flush = 1;
	314	return NULL;
	315	}
	316
	317	NAPI_GRO_CB(skb)->encap_mark = 1;
	318
	319	return inet_gro_receive(head, skb);
	320	}
	321
028e0a47 PA	322	INDIRECT_CALLABLE_DECLARE(int tcp6_gro_complete(struct sk_buff *, int));
028e0a47 PA	323	INDIRECT_CALLABLE_DECLARE(int udp6_gro_complete(struct sk_buff *, int));
aaa5d90b	324	INDIRECT_CALLABLE_SCOPE int ipv6_gro_complete(struct sk_buff *skb, int nhoff)
d1da932e VY	325	{
d1da932e VY	326	const struct net_offload *ops;
299603e8	327	struct ipv6hdr iph = (struct ipv6hdr )(skb->data + nhoff);
d1da932e VY	328	int err = -ENOSYS;
d1da932e VY	329
294acf1c PA	330	if (skb->encapsulation) {
294acf1c PA	331	skb_set_inner_protocol(skb, cpu_to_be16(ETH_P_IPV6));
feec0cb3	332	skb_set_inner_network_header(skb, nhoff);
294acf1c	333	}
feec0cb3	334
299603e8	335	iph->payload_len = htons(skb->len - nhoff - sizeof(*iph));
d1da932e VY	336
d1da932e VY	337	rcu_read_lock();
299603e8 JC	338
299603e8 JC	339	nhoff += sizeof(*iph) + ipv6_exthdrs_len(iph, &ops);
f191a1d1	340	if (WARN_ON(!ops \|\| !ops->callbacks.gro_complete))
d1da932e VY	341	goto out_unlock;
d1da932e VY	342
028e0a47 PA	343	err = INDIRECT_CALL_L4(ops->callbacks.gro_complete, tcp6_gro_complete,
028e0a47 PA	344	udp6_gro_complete, skb, nhoff);
d1da932e VY	345
	346	out_unlock:
	347	rcu_read_unlock();
	348
	349	return err;
	350	}
	351
feec0cb3 ED	352	static int sit_gro_complete(struct sk_buff *skb, int nhoff)
	353	{
	354	skb->encapsulation = 1;
7e13318d	355	skb_shinfo(skb)->gso_type \|= SKB_GSO_IPXIP4;
feec0cb3 ED	356	return ipv6_gro_complete(skb, nhoff);
	357	}
	358
815d22e5 TH	359	static int ip6ip6_gro_complete(struct sk_buff *skb, int nhoff)
	360	{
	361	skb->encapsulation = 1;
	362	skb_shinfo(skb)->gso_type \|= SKB_GSO_IPXIP6;
	363	return ipv6_gro_complete(skb, nhoff);
	364	}
	365
b8921ca8 TH	366	static int ip4ip6_gro_complete(struct sk_buff *skb, int nhoff)
	367	{
	368	skb->encapsulation = 1;
	369	skb_shinfo(skb)->gso_type \|= SKB_GSO_IPXIP6;
	370	return inet_gro_complete(skb, nhoff);
	371	}
	372
d1da932e VY	373	static struct packet_offload ipv6_packet_offload __read_mostly = {
d1da932e VY	374	.type = cpu_to_be16(ETH_P_IPV6),
f191a1d1	375	.callbacks = {
f191a1d1 VY	376	.gso_segment = ipv6_gso_segment,
	377	.gro_receive = ipv6_gro_receive,
	378	.gro_complete = ipv6_gro_complete,
	379	},
d1da932e VY	380	};
d1da932e VY	381
418e897e WB	382	static struct sk_buff sit_gso_segment(struct sk_buff skb,
	383	netdev_features_t features)
	384	{
	385	if (!(skb_shinfo(skb)->gso_type & SKB_GSO_IPXIP4))
	386	return ERR_PTR(-EINVAL);
	387
	388	return ipv6_gso_segment(skb, features);
	389	}
	390
	391	static struct sk_buff ip4ip6_gso_segment(struct sk_buff skb,
	392	netdev_features_t features)
	393	{
	394	if (!(skb_shinfo(skb)->gso_type & SKB_GSO_IPXIP6))
	395	return ERR_PTR(-EINVAL);
	396
	397	return inet_gso_segment(skb, features);
	398	}
	399
	400	static struct sk_buff ip6ip6_gso_segment(struct sk_buff skb,
	401	netdev_features_t features)
	402	{
	403	if (!(skb_shinfo(skb)->gso_type & SKB_GSO_IPXIP6))
	404	return ERR_PTR(-EINVAL);
	405
	406	return ipv6_gso_segment(skb, features);
	407	}
	408
61c1db7f ED	409	static const struct net_offload sit_offload = {
61c1db7f ED	410	.callbacks = {
418e897e	411	.gso_segment = sit_gso_segment,
815d22e5	412	.gro_receive = sit_ip6ip6_gro_receive,
feec0cb3	413	.gro_complete = sit_gro_complete,
61c1db7f ED	414	},
	415	};
	416
b8921ca8 TH	417	static const struct net_offload ip4ip6_offload = {
b8921ca8 TH	418	.callbacks = {
418e897e	419	.gso_segment = ip4ip6_gso_segment,
b8921ca8 TH	420	.gro_receive = ip4ip6_gro_receive,
	421	.gro_complete = ip4ip6_gro_complete,
	422	},
	423	};
	424
815d22e5 TH	425	static const struct net_offload ip6ip6_offload = {
815d22e5 TH	426	.callbacks = {
418e897e	427	.gso_segment = ip6ip6_gso_segment,
815d22e5 TH	428	.gro_receive = sit_ip6ip6_gro_receive,
	429	.gro_complete = ip6ip6_gro_complete,
	430	},
	431	};
c6b641a4	432	static int __init ipv6_offload_init(void)
d1da932e	433	{
c6b641a4 VY	434
	435	if (tcpv6_offload_init() < 0)
	436	pr_crit("%s: Cannot add TCP protocol offload\n", __func__);
c6b641a4 VY	437	if (ipv6_exthdrs_offload_init() < 0)
	438	pr_crit("%s: Cannot add EXTHDRS protocol offload\n", __func__);
	439
d1da932e	440	dev_add_offload(&ipv6_packet_offload);
61c1db7f ED	441
61c1db7f ED	442	inet_add_offload(&sit_offload, IPPROTO_IPV6);
815d22e5	443	inet6_add_offload(&ip6ip6_offload, IPPROTO_IPV6);
b8921ca8	444	inet6_add_offload(&ip4ip6_offload, IPPROTO_IPIP);
61c1db7f	445
c6b641a4	446	return 0;
d1da932e VY	447	}
d1da932e VY	448
c6b641a4	449	fs_initcall(ipv6_offload_init);