1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * xfrm_device.c - IPsec device offloading code.
5 * Copyright (c) 2015 secunet Security Networks AG
8 * Steffen Klassert <steffen.klassert@secunet.com>
11 #include <linux/errno.h>
12 #include <linux/module.h>
13 #include <linux/netdevice.h>
14 #include <linux/skbuff.h>
15 #include <linux/slab.h>
16 #include <linux/spinlock.h>
19 #include <linux/notifier.h>
21 #ifdef CONFIG_XFRM_OFFLOAD
22 static void __xfrm_transport_prep(struct xfrm_state *x, struct sk_buff *skb,
25 struct xfrm_offload *xo = xfrm_offload(skb);
27 skb_reset_mac_len(skb);
28 pskb_pull(skb, skb->mac_len + hsize + x->props.header_len);
30 if (xo->flags & XFRM_GSO_SEGMENT) {
31 skb_reset_transport_header(skb);
32 skb->transport_header -= x->props.header_len;
36 static void __xfrm_mode_tunnel_prep(struct xfrm_state *x, struct sk_buff *skb,
40 struct xfrm_offload *xo = xfrm_offload(skb);
42 if (xo->flags & XFRM_GSO_SEGMENT)
43 skb->transport_header = skb->network_header + hsize;
45 skb_reset_mac_len(skb);
46 pskb_pull(skb, skb->mac_len + x->props.header_len);
49 /* Adjust pointers into the packet when IPsec is done at layer2 */
50 static void xfrm_outer_mode_prep(struct xfrm_state *x, struct sk_buff *skb)
52 switch (x->outer_mode.encap) {
53 case XFRM_MODE_TUNNEL:
54 if (x->outer_mode.family == AF_INET)
55 return __xfrm_mode_tunnel_prep(x, skb,
56 sizeof(struct iphdr));
57 if (x->outer_mode.family == AF_INET6)
58 return __xfrm_mode_tunnel_prep(x, skb,
59 sizeof(struct ipv6hdr));
61 case XFRM_MODE_TRANSPORT:
62 if (x->outer_mode.family == AF_INET)
63 return __xfrm_transport_prep(x, skb,
64 sizeof(struct iphdr));
65 if (x->outer_mode.family == AF_INET6)
66 return __xfrm_transport_prep(x, skb,
67 sizeof(struct ipv6hdr));
69 case XFRM_MODE_ROUTEOPTIMIZATION:
70 case XFRM_MODE_IN_TRIGGER:
76 struct sk_buff *validate_xmit_xfrm(struct sk_buff *skb, netdev_features_t features, bool *again)
82 struct softnet_data *sd;
83 netdev_features_t esp_features = features;
84 struct xfrm_offload *xo = xfrm_offload(skb);
90 if (!(features & NETIF_F_HW_ESP))
91 esp_features = features & ~(NETIF_F_SG | NETIF_F_CSUM_MASK);
93 sp = skb_sec_path(skb);
94 x = sp->xvec[sp->len - 1];
95 if (xo->flags & XFRM_GRO || x->xso.flags & XFRM_OFFLOAD_INBOUND)
98 local_irq_save(flags);
99 sd = this_cpu_ptr(&softnet_data);
100 err = !skb_queue_empty(&sd->xfrm_backlog);
101 local_irq_restore(flags);
108 if (skb_is_gso(skb)) {
109 struct net_device *dev = skb->dev;
111 if (unlikely(x->xso.dev != dev)) {
112 struct sk_buff *segs;
114 /* Packet got rerouted, fixup features and segment it. */
115 esp_features = esp_features & ~(NETIF_F_HW_ESP
118 segs = skb_gso_segment(skb, esp_features);
121 atomic_long_inc(&dev->tx_dropped);
131 esp_features |= skb->dev->gso_partial_features;
132 xfrm_outer_mode_prep(x, skb);
134 xo->flags |= XFRM_DEV_RESUME;
136 err = x->type_offload->xmit(x, skb, esp_features);
138 if (err == -EINPROGRESS)
141 XFRM_INC_STATS(xs_net(x), LINUX_MIB_XFRMOUTSTATEPROTOERROR);
146 skb_push(skb, skb->data - skb_mac_header(skb));
154 struct sk_buff *nskb = skb2->next;
156 esp_features |= skb->dev->gso_partial_features;
157 skb_mark_not_on_list(skb2);
159 xo = xfrm_offload(skb2);
160 xo->flags |= XFRM_DEV_RESUME;
162 xfrm_outer_mode_prep(x, skb2);
164 err = x->type_offload->xmit(x, skb2, esp_features);
167 } else if (err != -EINPROGRESS) {
168 XFRM_INC_STATS(xs_net(x), LINUX_MIB_XFRMOUTSTATEPROTOERROR);
170 kfree_skb_list(skb2);
182 skb_push(skb2, skb2->data - skb_mac_header(skb2));
190 EXPORT_SYMBOL_GPL(validate_xmit_xfrm);
192 int xfrm_dev_state_add(struct net *net, struct xfrm_state *x,
193 struct xfrm_user_offload *xuo)
196 struct dst_entry *dst;
197 struct net_device *dev;
198 struct xfrm_state_offload *xso = &x->xso;
199 xfrm_address_t *saddr;
200 xfrm_address_t *daddr;
202 if (!x->type_offload)
205 /* We don't yet support UDP encapsulation and TFC padding. */
206 if (x->encap || x->tfcpad)
209 dev = dev_get_by_index(net, xuo->ifindex);
211 if (!(xuo->flags & XFRM_OFFLOAD_INBOUND)) {
212 saddr = &x->props.saddr;
213 daddr = &x->id.daddr;
215 saddr = &x->id.daddr;
216 daddr = &x->props.saddr;
219 dst = __xfrm_dst_lookup(net, 0, 0, saddr, daddr,
221 xfrm_smark_get(0, x));
231 if (!dev->xfrmdev_ops || !dev->xfrmdev_ops->xdo_dev_state_add) {
237 if (x->props.flags & XFRM_STATE_ESN &&
238 !dev->xfrmdev_ops->xdo_dev_state_advance_esn) {
245 xso->num_exthdrs = 1;
246 xso->flags = xuo->flags;
248 err = dev->xfrmdev_ops->xdo_dev_state_add(x);
250 xso->num_exthdrs = 0;
255 if (err != -EOPNOTSUPP)
261 EXPORT_SYMBOL_GPL(xfrm_dev_state_add);
263 bool xfrm_dev_offload_ok(struct sk_buff *skb, struct xfrm_state *x)
266 struct dst_entry *dst = skb_dst(skb);
267 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
268 struct net_device *dev = x->xso.dev;
270 if (!x->type_offload || x->encap)
273 if ((!dev || (dev == xfrm_dst_path(dst)->dev)) &&
274 (!xdst->child->xfrm && x->type->get_mtu)) {
275 mtu = x->type->get_mtu(x, xdst->child_mtu_cached);
280 if (skb_is_gso(skb) && skb_gso_validate_network_len(skb, mtu))
287 if (dev && dev->xfrmdev_ops && dev->xfrmdev_ops->xdo_dev_offload_ok)
288 return x->xso.dev->xfrmdev_ops->xdo_dev_offload_ok(skb, x);
292 EXPORT_SYMBOL_GPL(xfrm_dev_offload_ok);
294 void xfrm_dev_resume(struct sk_buff *skb)
296 struct net_device *dev = skb->dev;
297 int ret = NETDEV_TX_BUSY;
298 struct netdev_queue *txq;
299 struct softnet_data *sd;
303 txq = netdev_core_pick_tx(dev, skb, NULL);
305 HARD_TX_LOCK(dev, txq, smp_processor_id());
306 if (!netif_xmit_frozen_or_stopped(txq))
307 skb = dev_hard_start_xmit(skb, dev, txq, &ret);
308 HARD_TX_UNLOCK(dev, txq);
310 if (!dev_xmit_complete(ret)) {
311 local_irq_save(flags);
312 sd = this_cpu_ptr(&softnet_data);
313 skb_queue_tail(&sd->xfrm_backlog, skb);
314 raise_softirq_irqoff(NET_TX_SOFTIRQ);
315 local_irq_restore(flags);
319 EXPORT_SYMBOL_GPL(xfrm_dev_resume);
321 void xfrm_dev_backlog(struct softnet_data *sd)
323 struct sk_buff_head *xfrm_backlog = &sd->xfrm_backlog;
324 struct sk_buff_head list;
327 if (skb_queue_empty(xfrm_backlog))
330 __skb_queue_head_init(&list);
332 spin_lock(&xfrm_backlog->lock);
333 skb_queue_splice_init(xfrm_backlog, &list);
334 spin_unlock(&xfrm_backlog->lock);
336 while (!skb_queue_empty(&list)) {
337 skb = __skb_dequeue(&list);
338 xfrm_dev_resume(skb);
344 static int xfrm_api_check(struct net_device *dev)
346 #ifdef CONFIG_XFRM_OFFLOAD
347 if ((dev->features & NETIF_F_HW_ESP_TX_CSUM) &&
348 !(dev->features & NETIF_F_HW_ESP))
351 if ((dev->features & NETIF_F_HW_ESP) &&
352 (!(dev->xfrmdev_ops &&
353 dev->xfrmdev_ops->xdo_dev_state_add &&
354 dev->xfrmdev_ops->xdo_dev_state_delete)))
357 if (dev->features & (NETIF_F_HW_ESP | NETIF_F_HW_ESP_TX_CSUM))
364 static int xfrm_dev_register(struct net_device *dev)
366 return xfrm_api_check(dev);
369 static int xfrm_dev_feat_change(struct net_device *dev)
371 return xfrm_api_check(dev);
374 static int xfrm_dev_down(struct net_device *dev)
376 if (dev->features & NETIF_F_HW_ESP)
377 xfrm_dev_state_flush(dev_net(dev), dev, true);
382 static int xfrm_dev_event(struct notifier_block *this, unsigned long event, void *ptr)
384 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
387 case NETDEV_REGISTER:
388 return xfrm_dev_register(dev);
390 case NETDEV_FEAT_CHANGE:
391 return xfrm_dev_feat_change(dev);
394 return xfrm_dev_down(dev);
399 static struct notifier_block xfrm_dev_notifier = {
400 .notifier_call = xfrm_dev_event,
403 void __init xfrm_dev_init(void)
405 register_netdevice_notifier(&xfrm_dev_notifier);