2 * xfrm_device.c - IPsec device offloading code.
4 * Copyright (c) 2015 secunet Security Networks AG
7 * Steffen Klassert <steffen.klassert@secunet.com>
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.
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>
23 #include <linux/notifier.h>
25 #ifdef CONFIG_XFRM_OFFLOAD
26 struct sk_buff *validate_xmit_xfrm(struct sk_buff *skb, netdev_features_t features, bool *again)
32 struct softnet_data *sd;
33 netdev_features_t esp_features = features;
34 struct xfrm_offload *xo = xfrm_offload(skb);
36 if (!xo || (xo->flags & XFRM_XMIT))
39 if (!(features & NETIF_F_HW_ESP))
40 esp_features = features & ~(NETIF_F_SG | NETIF_F_CSUM_MASK);
42 x = skb->sp->xvec[skb->sp->len - 1];
43 if (xo->flags & XFRM_GRO || x->xso.flags & XFRM_OFFLOAD_INBOUND)
46 local_irq_save(flags);
47 sd = this_cpu_ptr(&softnet_data);
48 err = !skb_queue_empty(&sd->xfrm_backlog);
49 local_irq_restore(flags);
56 xo->flags |= XFRM_XMIT;
58 if (skb_is_gso(skb)) {
59 struct net_device *dev = skb->dev;
61 if (unlikely(x->xso.dev != dev)) {
64 /* Packet got rerouted, fixup features and segment it. */
65 esp_features = esp_features & ~(NETIF_F_HW_ESP
68 segs = skb_gso_segment(skb, esp_features);
71 atomic_long_inc(&dev->tx_dropped);
81 x->outer_mode->xmit(x, skb);
83 xo->flags |= XFRM_DEV_RESUME;
85 err = x->type_offload->xmit(x, skb, esp_features);
87 if (err == -EINPROGRESS)
90 XFRM_INC_STATS(xs_net(x), LINUX_MIB_XFRMOUTSTATEPROTOERROR);
95 skb_push(skb, skb->data - skb_mac_header(skb));
103 struct sk_buff *nskb = skb2->next;
106 xo = xfrm_offload(skb2);
107 xo->flags |= XFRM_DEV_RESUME;
109 x->outer_mode->xmit(x, skb2);
111 err = x->type_offload->xmit(x, skb2, esp_features);
114 } else if (err != -EINPROGRESS) {
115 XFRM_INC_STATS(xs_net(x), LINUX_MIB_XFRMOUTSTATEPROTOERROR);
117 kfree_skb_list(skb2);
129 skb_push(skb2, skb2->data - skb_mac_header(skb2));
137 EXPORT_SYMBOL_GPL(validate_xmit_xfrm);
139 int xfrm_dev_state_add(struct net *net, struct xfrm_state *x,
140 struct xfrm_user_offload *xuo)
143 struct dst_entry *dst;
144 struct net_device *dev;
145 struct xfrm_state_offload *xso = &x->xso;
146 xfrm_address_t *saddr;
147 xfrm_address_t *daddr;
149 if (!x->type_offload)
152 /* We don't yet support UDP encapsulation and TFC padding. */
153 if (x->encap || x->tfcpad)
156 dev = dev_get_by_index(net, xuo->ifindex);
158 if (!(xuo->flags & XFRM_OFFLOAD_INBOUND)) {
159 saddr = &x->props.saddr;
160 daddr = &x->id.daddr;
162 saddr = &x->id.daddr;
163 daddr = &x->props.saddr;
166 dst = __xfrm_dst_lookup(net, 0, 0, saddr, daddr,
168 xfrm_smark_get(0, x));
178 if (!dev->xfrmdev_ops || !dev->xfrmdev_ops->xdo_dev_state_add) {
184 if (x->props.flags & XFRM_STATE_ESN &&
185 !dev->xfrmdev_ops->xdo_dev_state_advance_esn) {
192 xso->num_exthdrs = 1;
193 xso->flags = xuo->flags;
195 err = dev->xfrmdev_ops->xdo_dev_state_add(x);
204 EXPORT_SYMBOL_GPL(xfrm_dev_state_add);
206 bool xfrm_dev_offload_ok(struct sk_buff *skb, struct xfrm_state *x)
209 struct dst_entry *dst = skb_dst(skb);
210 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
211 struct net_device *dev = x->xso.dev;
213 if (!x->type_offload || x->encap)
216 if ((!dev || (dev == xfrm_dst_path(dst)->dev)) &&
217 (!xdst->child->xfrm && x->type->get_mtu)) {
218 mtu = x->type->get_mtu(x, xdst->child_mtu_cached);
223 if (skb_is_gso(skb) && skb_gso_validate_network_len(skb, mtu))
230 if (dev && dev->xfrmdev_ops && dev->xfrmdev_ops->xdo_dev_offload_ok)
231 return x->xso.dev->xfrmdev_ops->xdo_dev_offload_ok(skb, x);
235 EXPORT_SYMBOL_GPL(xfrm_dev_offload_ok);
237 void xfrm_dev_resume(struct sk_buff *skb)
239 struct net_device *dev = skb->dev;
240 int ret = NETDEV_TX_BUSY;
241 struct netdev_queue *txq;
242 struct softnet_data *sd;
246 txq = netdev_pick_tx(dev, skb, NULL);
248 HARD_TX_LOCK(dev, txq, smp_processor_id());
249 if (!netif_xmit_frozen_or_stopped(txq))
250 skb = dev_hard_start_xmit(skb, dev, txq, &ret);
251 HARD_TX_UNLOCK(dev, txq);
253 if (!dev_xmit_complete(ret)) {
254 local_irq_save(flags);
255 sd = this_cpu_ptr(&softnet_data);
256 skb_queue_tail(&sd->xfrm_backlog, skb);
257 raise_softirq_irqoff(NET_TX_SOFTIRQ);
258 local_irq_restore(flags);
262 EXPORT_SYMBOL_GPL(xfrm_dev_resume);
264 void xfrm_dev_backlog(struct softnet_data *sd)
266 struct sk_buff_head *xfrm_backlog = &sd->xfrm_backlog;
267 struct sk_buff_head list;
270 if (skb_queue_empty(xfrm_backlog))
273 __skb_queue_head_init(&list);
275 spin_lock(&xfrm_backlog->lock);
276 skb_queue_splice_init(xfrm_backlog, &list);
277 spin_unlock(&xfrm_backlog->lock);
279 while (!skb_queue_empty(&list)) {
280 skb = __skb_dequeue(&list);
281 xfrm_dev_resume(skb);
287 static int xfrm_api_check(struct net_device *dev)
289 #ifdef CONFIG_XFRM_OFFLOAD
290 if ((dev->features & NETIF_F_HW_ESP_TX_CSUM) &&
291 !(dev->features & NETIF_F_HW_ESP))
294 if ((dev->features & NETIF_F_HW_ESP) &&
295 (!(dev->xfrmdev_ops &&
296 dev->xfrmdev_ops->xdo_dev_state_add &&
297 dev->xfrmdev_ops->xdo_dev_state_delete)))
300 if (dev->features & (NETIF_F_HW_ESP | NETIF_F_HW_ESP_TX_CSUM))
307 static int xfrm_dev_register(struct net_device *dev)
309 return xfrm_api_check(dev);
312 static int xfrm_dev_feat_change(struct net_device *dev)
314 return xfrm_api_check(dev);
317 static int xfrm_dev_down(struct net_device *dev)
319 if (dev->features & NETIF_F_HW_ESP)
320 xfrm_dev_state_flush(dev_net(dev), dev, true);
325 static int xfrm_dev_event(struct notifier_block *this, unsigned long event, void *ptr)
327 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
330 case NETDEV_REGISTER:
331 return xfrm_dev_register(dev);
333 case NETDEV_FEAT_CHANGE:
334 return xfrm_dev_feat_change(dev);
337 case NETDEV_UNREGISTER:
338 return xfrm_dev_down(dev);
343 static struct notifier_block xfrm_dev_notifier = {
344 .notifier_call = xfrm_dev_event,
347 void __init xfrm_dev_init(void)
349 register_netdevice_notifier(&xfrm_dev_notifier);