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 if (xo->flags & XFRM_GSO_SEGMENT)
29 skb->transport_header -= x->props.header_len;
31 pskb_pull(skb, skb_transport_offset(skb) + x->props.header_len);
34 static void __xfrm_mode_tunnel_prep(struct xfrm_state *x, struct sk_buff *skb,
38 struct xfrm_offload *xo = xfrm_offload(skb);
40 if (xo->flags & XFRM_GSO_SEGMENT)
41 skb->transport_header = skb->network_header + hsize;
43 skb_reset_mac_len(skb);
44 pskb_pull(skb, skb->mac_len + x->props.header_len);
47 /* Adjust pointers into the packet when IPsec is done at layer2 */
48 static void xfrm_outer_mode_prep(struct xfrm_state *x, struct sk_buff *skb)
50 switch (x->outer_mode.encap) {
51 case XFRM_MODE_TUNNEL:
52 if (x->outer_mode.family == AF_INET)
53 return __xfrm_mode_tunnel_prep(x, skb,
54 sizeof(struct iphdr));
55 if (x->outer_mode.family == AF_INET6)
56 return __xfrm_mode_tunnel_prep(x, skb,
57 sizeof(struct ipv6hdr));
59 case XFRM_MODE_TRANSPORT:
60 if (x->outer_mode.family == AF_INET)
61 return __xfrm_transport_prep(x, skb,
62 sizeof(struct iphdr));
63 if (x->outer_mode.family == AF_INET6)
64 return __xfrm_transport_prep(x, skb,
65 sizeof(struct ipv6hdr));
67 case XFRM_MODE_ROUTEOPTIMIZATION:
68 case XFRM_MODE_IN_TRIGGER:
74 struct sk_buff *validate_xmit_xfrm(struct sk_buff *skb, netdev_features_t features, bool *again)
80 struct softnet_data *sd;
81 netdev_features_t esp_features = features;
82 struct xfrm_offload *xo = xfrm_offload(skb);
85 if (!xo || (xo->flags & XFRM_XMIT))
88 if (!(features & NETIF_F_HW_ESP))
89 esp_features = features & ~(NETIF_F_SG | NETIF_F_CSUM_MASK);
91 sp = skb_sec_path(skb);
92 x = sp->xvec[sp->len - 1];
93 if (xo->flags & XFRM_GRO || x->xso.flags & XFRM_OFFLOAD_INBOUND)
96 local_irq_save(flags);
97 sd = this_cpu_ptr(&softnet_data);
98 err = !skb_queue_empty(&sd->xfrm_backlog);
99 local_irq_restore(flags);
106 xo->flags |= XFRM_XMIT;
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 if (xuo->flags & ~(XFRM_OFFLOAD_IPV6 | XFRM_OFFLOAD_INBOUND))
212 dev = dev_get_by_index(net, xuo->ifindex);
214 if (!(xuo->flags & XFRM_OFFLOAD_INBOUND)) {
215 saddr = &x->props.saddr;
216 daddr = &x->id.daddr;
218 saddr = &x->id.daddr;
219 daddr = &x->props.saddr;
222 dst = __xfrm_dst_lookup(net, 0, 0, saddr, daddr,
224 xfrm_smark_get(0, x));
234 if (!dev->xfrmdev_ops || !dev->xfrmdev_ops->xdo_dev_state_add) {
240 if (x->props.flags & XFRM_STATE_ESN &&
241 !dev->xfrmdev_ops->xdo_dev_state_advance_esn) {
248 xso->num_exthdrs = 1;
249 /* Don't forward bit that is not implemented */
250 xso->flags = xuo->flags & ~XFRM_OFFLOAD_IPV6;
252 err = dev->xfrmdev_ops->xdo_dev_state_add(x);
254 xso->num_exthdrs = 0;
259 if (err != -EOPNOTSUPP)
265 EXPORT_SYMBOL_GPL(xfrm_dev_state_add);
267 bool xfrm_dev_offload_ok(struct sk_buff *skb, struct xfrm_state *x)
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;
274 if (!x->type_offload || x->encap)
277 if ((!dev || (dev == xfrm_dst_path(dst)->dev)) &&
278 (!xdst->child->xfrm)) {
279 mtu = xfrm_state_mtu(x, xdst->child_mtu_cached);
283 if (skb_is_gso(skb) && skb_gso_validate_network_len(skb, mtu))
290 if (dev && dev->xfrmdev_ops && dev->xfrmdev_ops->xdo_dev_offload_ok)
291 return x->xso.dev->xfrmdev_ops->xdo_dev_offload_ok(skb, x);
295 EXPORT_SYMBOL_GPL(xfrm_dev_offload_ok);
297 void xfrm_dev_resume(struct sk_buff *skb)
299 struct net_device *dev = skb->dev;
300 int ret = NETDEV_TX_BUSY;
301 struct netdev_queue *txq;
302 struct softnet_data *sd;
306 txq = netdev_core_pick_tx(dev, skb, NULL);
308 HARD_TX_LOCK(dev, txq, smp_processor_id());
309 if (!netif_xmit_frozen_or_stopped(txq))
310 skb = dev_hard_start_xmit(skb, dev, txq, &ret);
311 HARD_TX_UNLOCK(dev, txq);
313 if (!dev_xmit_complete(ret)) {
314 local_irq_save(flags);
315 sd = this_cpu_ptr(&softnet_data);
316 skb_queue_tail(&sd->xfrm_backlog, skb);
317 raise_softirq_irqoff(NET_TX_SOFTIRQ);
318 local_irq_restore(flags);
322 EXPORT_SYMBOL_GPL(xfrm_dev_resume);
324 void xfrm_dev_backlog(struct softnet_data *sd)
326 struct sk_buff_head *xfrm_backlog = &sd->xfrm_backlog;
327 struct sk_buff_head list;
330 if (skb_queue_empty(xfrm_backlog))
333 __skb_queue_head_init(&list);
335 spin_lock(&xfrm_backlog->lock);
336 skb_queue_splice_init(xfrm_backlog, &list);
337 spin_unlock(&xfrm_backlog->lock);
339 while (!skb_queue_empty(&list)) {
340 skb = __skb_dequeue(&list);
341 xfrm_dev_resume(skb);
347 static int xfrm_api_check(struct net_device *dev)
349 #ifdef CONFIG_XFRM_OFFLOAD
350 if ((dev->features & NETIF_F_HW_ESP_TX_CSUM) &&
351 !(dev->features & NETIF_F_HW_ESP))
354 if ((dev->features & NETIF_F_HW_ESP) &&
355 (!(dev->xfrmdev_ops &&
356 dev->xfrmdev_ops->xdo_dev_state_add &&
357 dev->xfrmdev_ops->xdo_dev_state_delete)))
360 if (dev->features & (NETIF_F_HW_ESP | NETIF_F_HW_ESP_TX_CSUM))
367 static int xfrm_dev_register(struct net_device *dev)
369 return xfrm_api_check(dev);
372 static int xfrm_dev_feat_change(struct net_device *dev)
374 return xfrm_api_check(dev);
377 static int xfrm_dev_down(struct net_device *dev)
379 if (dev->features & NETIF_F_HW_ESP)
380 xfrm_dev_state_flush(dev_net(dev), dev, true);
385 static int xfrm_dev_event(struct notifier_block *this, unsigned long event, void *ptr)
387 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
390 case NETDEV_REGISTER:
391 return xfrm_dev_register(dev);
393 case NETDEV_FEAT_CHANGE:
394 return xfrm_dev_feat_change(dev);
397 case NETDEV_UNREGISTER:
398 return xfrm_dev_down(dev);
403 static struct notifier_block xfrm_dev_notifier = {
404 .notifier_call = xfrm_dev_event,
407 void __init xfrm_dev_init(void)
409 register_netdevice_notifier(&xfrm_dev_notifier);