[linux-block.git] / net / xfrm / xfrm_device.c

/*
 * xfrm_device.c - IPsec device offloading code.
 *
 * Copyright (c) 2015 secunet Security Networks AG
 *
 * Author:
 * Steffen Klassert <steffen.klassert@secunet.com>
 *
 * 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/errno.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <net/dst.h>
#include <net/xfrm.h>
#include <linux/notifier.h>

#ifdef CONFIG_XFRM_OFFLOAD
static void __xfrm_transport_prep(struct xfrm_state *x, struct sk_buff *skb,
				  unsigned int hsize)
{
	struct xfrm_offload *xo = xfrm_offload(skb);

	skb_reset_mac_len(skb);
	pskb_pull(skb, skb->mac_len + hsize + x->props.header_len);

	if (xo->flags & XFRM_GSO_SEGMENT) {
		skb_reset_transport_header(skb);
		skb->transport_header -= x->props.header_len;
	}
}

static void __xfrm_mode_tunnel_prep(struct xfrm_state *x, struct sk_buff *skb,
				    unsigned int hsize)

{
	struct xfrm_offload *xo = xfrm_offload(skb);

	if (xo->flags & XFRM_GSO_SEGMENT)
		skb->transport_header = skb->network_header + hsize;

	skb_reset_mac_len(skb);
	pskb_pull(skb, skb->mac_len + x->props.header_len);
}

/* Adjust pointers into the packet when IPsec is done at layer2 */
static void xfrm_outer_mode_prep(struct xfrm_state *x, struct sk_buff *skb)
{
	switch (x->outer_mode.encap) {
	case XFRM_MODE_TUNNEL:
		if (x->outer_mode.family == AF_INET)
			return __xfrm_mode_tunnel_prep(x, skb,
						       sizeof(struct iphdr));
		if (x->outer_mode.family == AF_INET6)
			return __xfrm_mode_tunnel_prep(x, skb,
						       sizeof(struct ipv6hdr));
		break;
	case XFRM_MODE_TRANSPORT:
		if (x->outer_mode.family == AF_INET)
			return __xfrm_transport_prep(x, skb,
						     sizeof(struct iphdr));
		if (x->outer_mode.family == AF_INET6)
			return __xfrm_transport_prep(x, skb,
						     sizeof(struct ipv6hdr));
		break;
	case XFRM_MODE_ROUTEOPTIMIZATION:
	case XFRM_MODE_IN_TRIGGER:
	case XFRM_MODE_BEET:
		break;
	}
}

struct sk_buff *validate_xmit_xfrm(struct sk_buff *skb, netdev_features_t features, bool *again)
{
	int err;
	unsigned long flags;
	struct xfrm_state *x;
	struct sk_buff *skb2;
	struct softnet_data *sd;
	netdev_features_t esp_features = features;
	struct xfrm_offload *xo = xfrm_offload(skb);
	struct sec_path *sp;

	if (!xo)
		return skb;

	if (!(features & NETIF_F_HW_ESP))
		esp_features = features & ~(NETIF_F_SG | NETIF_F_CSUM_MASK);

	sp = skb_sec_path(skb);
	x = sp->xvec[sp->len - 1];
	if (xo->flags & XFRM_GRO || x->xso.flags & XFRM_OFFLOAD_INBOUND)
		return skb;

	local_irq_save(flags);
	sd = this_cpu_ptr(&softnet_data);
	err = !skb_queue_empty(&sd->xfrm_backlog);
	local_irq_restore(flags);

	if (err) {
		*again = true;
		return skb;
	}

	if (skb_is_gso(skb)) {
		struct net_device *dev = skb->dev;

		if (unlikely(x->xso.dev != dev)) {
			struct sk_buff *segs;

			/* Packet got rerouted, fixup features and segment it. */
			esp_features = esp_features & ~(NETIF_F_HW_ESP
							| NETIF_F_GSO_ESP);

			segs = skb_gso_segment(skb, esp_features);
			if (IS_ERR(segs)) {
				kfree_skb(skb);
				atomic_long_inc(&dev->tx_dropped);
				return NULL;
			} else {
				consume_skb(skb);
				skb = segs;
			}
		}
	}

	if (!skb->next) {
		esp_features |= skb->dev->gso_partial_features;
		xfrm_outer_mode_prep(x, skb);

		xo->flags |= XFRM_DEV_RESUME;

		err = x->type_offload->xmit(x, skb, esp_features);
		if (err) {
			if (err == -EINPROGRESS)
				return NULL;

			XFRM_INC_STATS(xs_net(x), LINUX_MIB_XFRMOUTSTATEPROTOERROR);
			kfree_skb(skb);
			return NULL;
		}

		skb_push(skb, skb->data - skb_mac_header(skb));

		return skb;
	}

	skb2 = skb;

	do {
		struct sk_buff *nskb = skb2->next;

		esp_features |= skb->dev->gso_partial_features;
		skb_mark_not_on_list(skb2);

		xo = xfrm_offload(skb2);
		xo->flags |= XFRM_DEV_RESUME;

		xfrm_outer_mode_prep(x, skb2);

		err = x->type_offload->xmit(x, skb2, esp_features);
		if (!err) {
			skb2->next = nskb;
		} else if (err != -EINPROGRESS) {
			XFRM_INC_STATS(xs_net(x), LINUX_MIB_XFRMOUTSTATEPROTOERROR);
			skb2->next = nskb;
			kfree_skb_list(skb2);
			return NULL;
		} else {
			if (skb == skb2)
				skb = nskb;

			if (!skb)
				return NULL;

			goto skip_push;
		}

		skb_push(skb2, skb2->data - skb_mac_header(skb2));

skip_push:
		skb2 = nskb;
	} while (skb2);

	return skb;
}
EXPORT_SYMBOL_GPL(validate_xmit_xfrm);

int xfrm_dev_state_add(struct net *net, struct xfrm_state *x,
		       struct xfrm_user_offload *xuo)
{
	int err;
	struct dst_entry *dst;
	struct net_device *dev;
	struct xfrm_state_offload *xso = &x->xso;
	xfrm_address_t *saddr;
	xfrm_address_t *daddr;

	if (!x->type_offload)
		return -EINVAL;

	/* We don't yet support UDP encapsulation and TFC padding. */
	if (x->encap || x->tfcpad)
		return -EINVAL;

	dev = dev_get_by_index(net, xuo->ifindex);
	if (!dev) {
		if (!(xuo->flags & XFRM_OFFLOAD_INBOUND)) {
			saddr = &x->props.saddr;
			daddr = &x->id.daddr;
		} else {
			saddr = &x->id.daddr;
			daddr = &x->props.saddr;
		}

		dst = __xfrm_dst_lookup(net, 0, 0, saddr, daddr,
					x->props.family,
					xfrm_smark_get(0, x));
		if (IS_ERR(dst))
			return 0;

		dev = dst->dev;

		dev_hold(dev);
		dst_release(dst);
	}

	if (!dev->xfrmdev_ops || !dev->xfrmdev_ops->xdo_dev_state_add) {
		xso->dev = NULL;
		dev_put(dev);
		return 0;
	}

	if (x->props.flags & XFRM_STATE_ESN &&
	    !dev->xfrmdev_ops->xdo_dev_state_advance_esn) {
		xso->dev = NULL;
		dev_put(dev);
		return -EINVAL;
	}

	xso->dev = dev;
	xso->num_exthdrs = 1;
	xso->flags = xuo->flags;

	err = dev->xfrmdev_ops->xdo_dev_state_add(x);
	if (err) {
		xso->num_exthdrs = 0;
		xso->flags = 0;
		xso->dev = NULL;
		dev_put(dev);

		if (err != -EOPNOTSUPP)
			return err;
	}

	return 0;
}
EXPORT_SYMBOL_GPL(xfrm_dev_state_add);

bool xfrm_dev_offload_ok(struct sk_buff *skb, struct xfrm_state *x)
{
	int mtu;
	struct dst_entry *dst = skb_dst(skb);
	struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
	struct net_device *dev = x->xso.dev;

	if (!x->type_offload || x->encap)
		return false;

	if ((!dev || (dev == xfrm_dst_path(dst)->dev)) &&
	    (!xdst->child->xfrm && x->type->get_mtu)) {
		mtu = x->type->get_mtu(x, xdst->child_mtu_cached);

		if (skb->len <= mtu)
			goto ok;

		if (skb_is_gso(skb) && skb_gso_validate_network_len(skb, mtu))
			goto ok;
	}

	return false;

ok:
	if (dev && dev->xfrmdev_ops && dev->xfrmdev_ops->xdo_dev_offload_ok)
		return x->xso.dev->xfrmdev_ops->xdo_dev_offload_ok(skb, x);

	return true;
}
EXPORT_SYMBOL_GPL(xfrm_dev_offload_ok);

void xfrm_dev_resume(struct sk_buff *skb)
{
	struct net_device *dev = skb->dev;
	int ret = NETDEV_TX_BUSY;
	struct netdev_queue *txq;
	struct softnet_data *sd;
	unsigned long flags;

	rcu_read_lock();
	txq = netdev_core_pick_tx(dev, skb, NULL);

	HARD_TX_LOCK(dev, txq, smp_processor_id());
	if (!netif_xmit_frozen_or_stopped(txq))
		skb = dev_hard_start_xmit(skb, dev, txq, &ret);
	HARD_TX_UNLOCK(dev, txq);

	if (!dev_xmit_complete(ret)) {
		local_irq_save(flags);
		sd = this_cpu_ptr(&softnet_data);
		skb_queue_tail(&sd->xfrm_backlog, skb);
		raise_softirq_irqoff(NET_TX_SOFTIRQ);
		local_irq_restore(flags);
	}
	rcu_read_unlock();
}
EXPORT_SYMBOL_GPL(xfrm_dev_resume);

void xfrm_dev_backlog(struct softnet_data *sd)
{
	struct sk_buff_head *xfrm_backlog = &sd->xfrm_backlog;
	struct sk_buff_head list;
	struct sk_buff *skb;

	if (skb_queue_empty(xfrm_backlog))
		return;

	__skb_queue_head_init(&list);

	spin_lock(&xfrm_backlog->lock);
	skb_queue_splice_init(xfrm_backlog, &list);
	spin_unlock(&xfrm_backlog->lock);

	while (!skb_queue_empty(&list)) {
		skb = __skb_dequeue(&list);
		xfrm_dev_resume(skb);
	}

}
#endif

static int xfrm_api_check(struct net_device *dev)
{
#ifdef CONFIG_XFRM_OFFLOAD
	if ((dev->features & NETIF_F_HW_ESP_TX_CSUM) &&
	    !(dev->features & NETIF_F_HW_ESP))
		return NOTIFY_BAD;

	if ((dev->features & NETIF_F_HW_ESP) &&
	    (!(dev->xfrmdev_ops &&
	       dev->xfrmdev_ops->xdo_dev_state_add &&
	       dev->xfrmdev_ops->xdo_dev_state_delete)))
		return NOTIFY_BAD;
#else
	if (dev->features & (NETIF_F_HW_ESP | NETIF_F_HW_ESP_TX_CSUM))
		return NOTIFY_BAD;
#endif

	return NOTIFY_DONE;
}

static int xfrm_dev_register(struct net_device *dev)
{
	return xfrm_api_check(dev);
}

static int xfrm_dev_feat_change(struct net_device *dev)
{
	return xfrm_api_check(dev);
}

static int xfrm_dev_down(struct net_device *dev)
{
	if (dev->features & NETIF_F_HW_ESP)
		xfrm_dev_state_flush(dev_net(dev), dev, true);

	return NOTIFY_DONE;
}

static int xfrm_dev_event(struct notifier_block *this, unsigned long event, void *ptr)
{
	struct net_device *dev = netdev_notifier_info_to_dev(ptr);

	switch (event) {
	case NETDEV_REGISTER:
		return xfrm_dev_register(dev);

	case NETDEV_FEAT_CHANGE:
		return xfrm_dev_feat_change(dev);

	case NETDEV_DOWN:
		return xfrm_dev_down(dev);
	}
	return NOTIFY_DONE;
}

static struct notifier_block xfrm_dev_notifier = {
	.notifier_call	= xfrm_dev_event,
};

void __init xfrm_dev_init(void)
{
	register_netdevice_notifier(&xfrm_dev_notifier);
}
Commit	Line	Data
21f42cc9 SK	1	/*
	2	* xfrm_device.c - IPsec device offloading code.
	3	*
	4	* Copyright (c) 2015 secunet Security Networks AG
	5	*
	6	* Author:
	7	* Steffen Klassert <steffen.klassert@secunet.com>
	8	*
	9	* This program is free software; you can redistribute it and/or
	10	* modify it under the terms of the GNU General Public License
	11	* as published by the Free Software Foundation; either version
	12	* 2 of the License, or (at your option) any later version.
	13	*/
	14
	15	#include <linux/errno.h>
	16	#include <linux/module.h>
	17	#include <linux/netdevice.h>
	18	#include <linux/skbuff.h>
	19	#include <linux/slab.h>
	20	#include <linux/spinlock.h>
	21	#include <net/dst.h>
	22	#include <net/xfrm.h>
	23	#include <linux/notifier.h>
	24
b81f884a	25	#ifdef CONFIG_XFRM_OFFLOAD
303c5fab FW	26	static void __xfrm_transport_prep(struct xfrm_state x, struct sk_buff skb,
	27	unsigned int hsize)
	28	{
	29	struct xfrm_offload *xo = xfrm_offload(skb);
	30
	31	skb_reset_mac_len(skb);
	32	pskb_pull(skb, skb->mac_len + hsize + x->props.header_len);
	33
	34	if (xo->flags & XFRM_GSO_SEGMENT) {
	35	skb_reset_transport_header(skb);
	36	skb->transport_header -= x->props.header_len;
	37	}
	38	}
	39
	40	static void __xfrm_mode_tunnel_prep(struct xfrm_state x, struct sk_buff skb,
	41	unsigned int hsize)
	42
	43	{
	44	struct xfrm_offload *xo = xfrm_offload(skb);
	45
	46	if (xo->flags & XFRM_GSO_SEGMENT)
	47	skb->transport_header = skb->network_header + hsize;
	48
	49	skb_reset_mac_len(skb);
	50	pskb_pull(skb, skb->mac_len + x->props.header_len);
	51	}
	52
	53	/* Adjust pointers into the packet when IPsec is done at layer2 */
	54	static void xfrm_outer_mode_prep(struct xfrm_state x, struct sk_buff skb)
	55	{
c9500d7b	56	switch (x->outer_mode.encap) {
303c5fab	57	case XFRM_MODE_TUNNEL:
c9500d7b	58	if (x->outer_mode.family == AF_INET)
303c5fab FW	59	return __xfrm_mode_tunnel_prep(x, skb,
303c5fab FW	60	sizeof(struct iphdr));
c9500d7b	61	if (x->outer_mode.family == AF_INET6)
303c5fab FW	62	return __xfrm_mode_tunnel_prep(x, skb,
	63	sizeof(struct ipv6hdr));
	64	break;
	65	case XFRM_MODE_TRANSPORT:
c9500d7b	66	if (x->outer_mode.family == AF_INET)
303c5fab FW	67	return __xfrm_transport_prep(x, skb,
303c5fab FW	68	sizeof(struct iphdr));
c9500d7b	69	if (x->outer_mode.family == AF_INET6)
303c5fab FW	70	return __xfrm_transport_prep(x, skb,
	71	sizeof(struct ipv6hdr));
	72	break;
	73	case XFRM_MODE_ROUTEOPTIMIZATION:
	74	case XFRM_MODE_IN_TRIGGER:
	75	case XFRM_MODE_BEET:
	76	break;
	77	}
	78	}
	79
f53c7239	80	struct sk_buff validate_xmit_xfrm(struct sk_buff skb, netdev_features_t features, bool *again)
f6e27114 SK	81	{
f6e27114 SK	82	int err;
f53c7239	83	unsigned long flags;
f6e27114	84	struct xfrm_state *x;
3dca3f38	85	struct sk_buff *skb2;
f53c7239	86	struct softnet_data *sd;
3dca3f38	87	netdev_features_t esp_features = features;
f6e27114	88	struct xfrm_offload *xo = xfrm_offload(skb);
2294be0f	89	struct sec_path *sp;
f6e27114	90
3dca3f38 SK	91	if (!xo)
3dca3f38 SK	92	return skb;
f6e27114	93
3dca3f38 SK	94	if (!(features & NETIF_F_HW_ESP))
3dca3f38 SK	95	esp_features = features & ~(NETIF_F_SG \| NETIF_F_CSUM_MASK);
f6e27114	96
2294be0f FW	97	sp = skb_sec_path(skb);
2294be0f FW	98	x = sp->xvec[sp->len - 1];
3dca3f38 SK	99	if (xo->flags & XFRM_GRO \|\| x->xso.flags & XFRM_OFFLOAD_INBOUND)
	100	return skb;
	101
f53c7239 SK	102	local_irq_save(flags);
	103	sd = this_cpu_ptr(&softnet_data);
	104	err = !skb_queue_empty(&sd->xfrm_backlog);
	105	local_irq_restore(flags);
	106
	107	if (err) {
	108	*again = true;
	109	return skb;
	110	}
	111
3dca3f38 SK	112	if (skb_is_gso(skb)) {
	113	struct net_device *dev = skb->dev;
	114
fcb662de	115	if (unlikely(x->xso.dev != dev)) {
3dca3f38 SK	116	struct sk_buff *segs;
	117
	118	/* Packet got rerouted, fixup features and segment it. */
	119	esp_features = esp_features & ~(NETIF_F_HW_ESP
	120	\| NETIF_F_GSO_ESP);
	121
	122	segs = skb_gso_segment(skb, esp_features);
	123	if (IS_ERR(segs)) {
3dca3f38	124	kfree_skb(skb);
f53c7239	125	atomic_long_inc(&dev->tx_dropped);
3dca3f38 SK	126	return NULL;
	127	} else {
	128	consume_skb(skb);
	129	skb = segs;
	130	}
3dca3f38 SK	131	}
	132	}
	133
	134	if (!skb->next) {
65fd2c2a	135	esp_features \|= skb->dev->gso_partial_features;
303c5fab	136	xfrm_outer_mode_prep(x, skb);
f6e27114	137
f53c7239 SK	138	xo->flags \|= XFRM_DEV_RESUME;
f53c7239 SK	139
3dca3f38	140	err = x->type_offload->xmit(x, skb, esp_features);
f6e27114	141	if (err) {
f53c7239 SK	142	if (err == -EINPROGRESS)
	143	return NULL;
	144
f6e27114	145	XFRM_INC_STATS(xs_net(x), LINUX_MIB_XFRMOUTSTATEPROTOERROR);
3dca3f38 SK	146	kfree_skb(skb);
3dca3f38 SK	147	return NULL;
f6e27114 SK	148	}
	149
	150	skb_push(skb, skb->data - skb_mac_header(skb));
3dca3f38 SK	151
3dca3f38 SK	152	return skb;
f6e27114 SK	153	}
f6e27114 SK	154
3dca3f38	155	skb2 = skb;
3dca3f38 SK	156
	157	do {
	158	struct sk_buff *nskb = skb2->next;
65fd2c2a BP	159
65fd2c2a BP	160	esp_features \|= skb->dev->gso_partial_features;
a8305bff	161	skb_mark_not_on_list(skb2);
3dca3f38 SK	162
3dca3f38 SK	163	xo = xfrm_offload(skb2);
f53c7239	164	xo->flags \|= XFRM_DEV_RESUME;
3dca3f38	165
303c5fab	166	xfrm_outer_mode_prep(x, skb2);
3dca3f38 SK	167
3dca3f38 SK	168	err = x->type_offload->xmit(x, skb2, esp_features);
f53c7239 SK	169	if (!err) {
	170	skb2->next = nskb;
	171	} else if (err != -EINPROGRESS) {
3dca3f38 SK	172	XFRM_INC_STATS(xs_net(x), LINUX_MIB_XFRMOUTSTATEPROTOERROR);
	173	skb2->next = nskb;
	174	kfree_skb_list(skb2);
	175	return NULL;
f53c7239 SK	176	} else {
	177	if (skb == skb2)
	178	skb = nskb;
	179
	180	if (!skb)
	181	return NULL;
3dca3f38	182
f53c7239 SK	183	goto skip_push;
f53c7239 SK	184	}
3dca3f38 SK	185
	186	skb_push(skb2, skb2->data - skb_mac_header(skb2));
	187
f53c7239	188	skip_push:
3dca3f38 SK	189	skb2 = nskb;
	190	} while (skb2);
	191
	192	return skb;
f6e27114 SK	193	}
	194	EXPORT_SYMBOL_GPL(validate_xmit_xfrm);
	195
d77e38e6 SK	196	int xfrm_dev_state_add(struct net net, struct xfrm_state x,
	197	struct xfrm_user_offload *xuo)
	198	{
	199	int err;
	200	struct dst_entry *dst;
	201	struct net_device *dev;
	202	struct xfrm_state_offload *xso = &x->xso;
	203	xfrm_address_t *saddr;
	204	xfrm_address_t *daddr;
	205
	206	if (!x->type_offload)
ffdb5211	207	return -EINVAL;
d77e38e6	208
50bd870a YE	209	/* We don't yet support UDP encapsulation and TFC padding. */
50bd870a YE	210	if (x->encap \|\| x->tfcpad)
43024b9c	211	return -EINVAL;
d77e38e6 SK	212
	213	dev = dev_get_by_index(net, xuo->ifindex);
	214	if (!dev) {
	215	if (!(xuo->flags & XFRM_OFFLOAD_INBOUND)) {
	216	saddr = &x->props.saddr;
	217	daddr = &x->id.daddr;
	218	} else {
	219	saddr = &x->id.daddr;
	220	daddr = &x->props.saddr;
	221	}
	222
077fbac4	223	dst = __xfrm_dst_lookup(net, 0, 0, saddr, daddr,
9b42c1f1 SK	224	x->props.family,
9b42c1f1 SK	225	xfrm_smark_get(0, x));
d77e38e6 SK	226	if (IS_ERR(dst))
	227	return 0;
	228
	229	dev = dst->dev;
	230
	231	dev_hold(dev);
	232	dst_release(dst);
	233	}
	234
	235	if (!dev->xfrmdev_ops \|\| !dev->xfrmdev_ops->xdo_dev_state_add) {
67a63387	236	xso->dev = NULL;
d77e38e6 SK	237	dev_put(dev);
	238	return 0;
	239	}
	240
50bd870a YE	241	if (x->props.flags & XFRM_STATE_ESN &&
	242	!dev->xfrmdev_ops->xdo_dev_state_advance_esn) {
	243	xso->dev = NULL;
	244	dev_put(dev);
	245	return -EINVAL;
	246	}
	247
d77e38e6 SK	248	xso->dev = dev;
	249	xso->num_exthdrs = 1;
	250	xso->flags = xuo->flags;
	251
	252	err = dev->xfrmdev_ops->xdo_dev_state_add(x);
	253	if (err) {
4a132095 SN	254	xso->num_exthdrs = 0;
4a132095 SN	255	xso->flags = 0;
aa5dd6fa	256	xso->dev = NULL;
d77e38e6	257	dev_put(dev);
4a132095 SN	258
	259	if (err != -EOPNOTSUPP)
	260	return err;
d77e38e6 SK	261	}
	262
	263	return 0;
	264	}
	265	EXPORT_SYMBOL_GPL(xfrm_dev_state_add);
	266
	267	bool xfrm_dev_offload_ok(struct sk_buff skb, struct xfrm_state x)
	268	{
	269	int mtu;
	270	struct dst_entry *dst = skb_dst(skb);
	271	struct xfrm_dst xdst = (struct xfrm_dst )dst;
	272	struct net_device *dev = x->xso.dev;
	273
	274	if (!x->type_offload \|\| x->encap)
	275	return false;
	276
fcb662de SN	277	if ((!dev \|\| (dev == xfrm_dst_path(dst)->dev)) &&
fcb662de SN	278	(!xdst->child->xfrm && x->type->get_mtu)) {
d77e38e6 SK	279	mtu = x->type->get_mtu(x, xdst->child_mtu_cached);
	280
	281	if (skb->len <= mtu)
	282	goto ok;
	283
779b7931	284	if (skb_is_gso(skb) && skb_gso_validate_network_len(skb, mtu))
d77e38e6 SK	285	goto ok;
	286	}
	287
	288	return false;
	289
	290	ok:
	291	if (dev && dev->xfrmdev_ops && dev->xfrmdev_ops->xdo_dev_offload_ok)
	292	return x->xso.dev->xfrmdev_ops->xdo_dev_offload_ok(skb, x);
	293
	294	return true;
	295	}
	296	EXPORT_SYMBOL_GPL(xfrm_dev_offload_ok);
f53c7239 SK	297
	298	void xfrm_dev_resume(struct sk_buff *skb)
	299	{
	300	struct net_device *dev = skb->dev;
	301	int ret = NETDEV_TX_BUSY;
	302	struct netdev_queue *txq;
	303	struct softnet_data *sd;
	304	unsigned long flags;
	305
	306	rcu_read_lock();
4bd97d51	307	txq = netdev_core_pick_tx(dev, skb, NULL);
f53c7239 SK	308
	309	HARD_TX_LOCK(dev, txq, smp_processor_id());
	310	if (!netif_xmit_frozen_or_stopped(txq))
	311	skb = dev_hard_start_xmit(skb, dev, txq, &ret);
	312	HARD_TX_UNLOCK(dev, txq);
	313
	314	if (!dev_xmit_complete(ret)) {
	315	local_irq_save(flags);
	316	sd = this_cpu_ptr(&softnet_data);
	317	skb_queue_tail(&sd->xfrm_backlog, skb);
	318	raise_softirq_irqoff(NET_TX_SOFTIRQ);
	319	local_irq_restore(flags);
	320	}
	321	rcu_read_unlock();
	322	}
	323	EXPORT_SYMBOL_GPL(xfrm_dev_resume);
	324
	325	void xfrm_dev_backlog(struct softnet_data *sd)
	326	{
	327	struct sk_buff_head *xfrm_backlog = &sd->xfrm_backlog;
	328	struct sk_buff_head list;
	329	struct sk_buff *skb;
	330
	331	if (skb_queue_empty(xfrm_backlog))
	332	return;
	333
	334	__skb_queue_head_init(&list);
	335
	336	spin_lock(&xfrm_backlog->lock);
	337	skb_queue_splice_init(xfrm_backlog, &list);
	338	spin_unlock(&xfrm_backlog->lock);
	339
	340	while (!skb_queue_empty(&list)) {
	341	skb = __skb_dequeue(&list);
	342	xfrm_dev_resume(skb);
	343	}
	344
	345	}
b81f884a	346	#endif
d77e38e6	347
92a23206	348	static int xfrm_api_check(struct net_device *dev)
d77e38e6	349	{
92a23206	350	#ifdef CONFIG_XFRM_OFFLOAD
d77e38e6 SK	351	if ((dev->features & NETIF_F_HW_ESP_TX_CSUM) &&
	352	!(dev->features & NETIF_F_HW_ESP))
	353	return NOTIFY_BAD;
	354
92a23206 SN	355	if ((dev->features & NETIF_F_HW_ESP) &&
	356	(!(dev->xfrmdev_ops &&
	357	dev->xfrmdev_ops->xdo_dev_state_add &&
	358	dev->xfrmdev_ops->xdo_dev_state_delete)))
	359	return NOTIFY_BAD;
	360	#else
	361	if (dev->features & (NETIF_F_HW_ESP \| NETIF_F_HW_ESP_TX_CSUM))
	362	return NOTIFY_BAD;
	363	#endif
	364
d77e38e6 SK	365	return NOTIFY_DONE;
	366	}
	367
92a23206 SN	368	static int xfrm_dev_register(struct net_device *dev)
	369	{
	370	return xfrm_api_check(dev);
	371	}
	372
d77e38e6 SK	373	static int xfrm_dev_feat_change(struct net_device *dev)
d77e38e6 SK	374	{
92a23206	375	return xfrm_api_check(dev);
d77e38e6 SK	376	}
	377
	378	static int xfrm_dev_down(struct net_device *dev)
	379	{
2c1497bb	380	if (dev->features & NETIF_F_HW_ESP)
d77e38e6 SK	381	xfrm_dev_state_flush(dev_net(dev), dev, true);
d77e38e6 SK	382
d77e38e6 SK	383	return NOTIFY_DONE;
	384	}
	385
21f42cc9 SK	386	static int xfrm_dev_event(struct notifier_block this, unsigned long event, void ptr)
	387	{
	388	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
	389
	390	switch (event) {
d77e38e6 SK	391	case NETDEV_REGISTER:
	392	return xfrm_dev_register(dev);
	393
d77e38e6 SK	394	case NETDEV_FEAT_CHANGE:
	395	return xfrm_dev_feat_change(dev);
	396
21f42cc9	397	case NETDEV_DOWN:
d77e38e6	398	return xfrm_dev_down(dev);
21f42cc9 SK	399	}
	400	return NOTIFY_DONE;
	401	}
	402
	403	static struct notifier_block xfrm_dev_notifier = {
	404	.notifier_call = xfrm_dev_event,
	405	};
	406
e9a441b6	407	void __init xfrm_dev_init(void)
21f42cc9 SK	408	{
	409	register_netdevice_notifier(&xfrm_dev_notifier);
	410	}