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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>
17#include <net/dst.h>
18#include <net/xfrm.h>
19#include <linux/notifier.h>
20
21#ifdef CONFIG_XFRM_OFFLOAD
22static void __xfrm_transport_prep(struct xfrm_state *x, struct sk_buff *skb,
23 unsigned int hsize)
24{
25 struct xfrm_offload *xo = xfrm_offload(skb);
26
27 skb_reset_mac_len(skb);
28 if (xo->flags & XFRM_GSO_SEGMENT)
29 skb->transport_header -= x->props.header_len;
30
31 pskb_pull(skb, skb_transport_offset(skb) + x->props.header_len);
32}
33
34static void __xfrm_mode_tunnel_prep(struct xfrm_state *x, struct sk_buff *skb,
35 unsigned int hsize)
36
37{
38 struct xfrm_offload *xo = xfrm_offload(skb);
39
40 if (xo->flags & XFRM_GSO_SEGMENT)
41 skb->transport_header = skb->network_header + hsize;
42
43 skb_reset_mac_len(skb);
44 pskb_pull(skb, skb->mac_len + x->props.header_len);
45}
46
47static void __xfrm_mode_beet_prep(struct xfrm_state *x, struct sk_buff *skb,
48 unsigned int hsize)
49{
50 struct xfrm_offload *xo = xfrm_offload(skb);
51 int phlen = 0;
52
53 if (xo->flags & XFRM_GSO_SEGMENT)
54 skb->transport_header = skb->network_header + hsize;
55
56 skb_reset_mac_len(skb);
57 if (x->sel.family != AF_INET6) {
58 phlen = IPV4_BEET_PHMAXLEN;
59 if (x->outer_mode.family == AF_INET6)
60 phlen += sizeof(struct ipv6hdr) - sizeof(struct iphdr);
61 }
62
63 pskb_pull(skb, skb->mac_len + hsize + (x->props.header_len - phlen));
64}
65
66
67static void xfrm_outer_mode_prep(struct xfrm_state *x, struct sk_buff *skb)
68{
69 switch (x->outer_mode.encap) {
70 case XFRM_MODE_TUNNEL:
71 if (x->outer_mode.family == AF_INET)
72 return __xfrm_mode_tunnel_prep(x, skb,
73 sizeof(struct iphdr));
74 if (x->outer_mode.family == AF_INET6)
75 return __xfrm_mode_tunnel_prep(x, skb,
76 sizeof(struct ipv6hdr));
77 break;
78 case XFRM_MODE_TRANSPORT:
79 if (x->outer_mode.family == AF_INET)
80 return __xfrm_transport_prep(x, skb,
81 sizeof(struct iphdr));
82 if (x->outer_mode.family == AF_INET6)
83 return __xfrm_transport_prep(x, skb,
84 sizeof(struct ipv6hdr));
85 break;
86 case XFRM_MODE_BEET:
87 if (x->outer_mode.family == AF_INET)
88 return __xfrm_mode_beet_prep(x, skb,
89 sizeof(struct iphdr));
90 if (x->outer_mode.family == AF_INET6)
91 return __xfrm_mode_beet_prep(x, skb,
92 sizeof(struct ipv6hdr));
93 break;
94 case XFRM_MODE_ROUTEOPTIMIZATION:
95 case XFRM_MODE_IN_TRIGGER:
96 break;
97 }
98}
99
100struct sk_buff *validate_xmit_xfrm(struct sk_buff *skb, netdev_features_t features, bool *again)
101{
102 int err;
103 unsigned long flags;
104 struct xfrm_state *x;
105 struct softnet_data *sd;
106 struct sk_buff *skb2, *nskb, *pskb = NULL;
107 netdev_features_t esp_features = features;
108 struct xfrm_offload *xo = xfrm_offload(skb);
109 struct net_device *dev = skb->dev;
110 struct sec_path *sp;
111
112 if (!xo || (xo->flags & XFRM_XMIT))
113 return skb;
114
115 if (!(features & NETIF_F_HW_ESP))
116 esp_features = features & ~(NETIF_F_SG | NETIF_F_CSUM_MASK);
117
118 sp = skb_sec_path(skb);
119 x = sp->xvec[sp->len - 1];
120 if (xo->flags & XFRM_GRO || x->xso.flags & XFRM_OFFLOAD_INBOUND)
121 return skb;
122
123
124 if ((x->xso.dev != dev) && (x->xso.real_dev == dev))
125 return skb;
126
127 local_irq_save(flags);
128 sd = this_cpu_ptr(&softnet_data);
129 err = !skb_queue_empty(&sd->xfrm_backlog);
130 local_irq_restore(flags);
131
132 if (err) {
133 *again = true;
134 return skb;
135 }
136
137 if (skb_is_gso(skb) && unlikely(x->xso.dev != dev)) {
138 struct sk_buff *segs;
139
140
141 esp_features = esp_features & ~(NETIF_F_HW_ESP | NETIF_F_GSO_ESP);
142
143 segs = skb_gso_segment(skb, esp_features);
144 if (IS_ERR(segs)) {
145 kfree_skb(skb);
146 atomic_long_inc(&dev->tx_dropped);
147 return NULL;
148 } else {
149 consume_skb(skb);
150 skb = segs;
151 }
152 }
153
154 if (!skb->next) {
155 esp_features |= skb->dev->gso_partial_features;
156 xfrm_outer_mode_prep(x, skb);
157
158 xo->flags |= XFRM_DEV_RESUME;
159
160 err = x->type_offload->xmit(x, skb, esp_features);
161 if (err) {
162 if (err == -EINPROGRESS)
163 return NULL;
164
165 XFRM_INC_STATS(xs_net(x), LINUX_MIB_XFRMOUTSTATEPROTOERROR);
166 kfree_skb(skb);
167 return NULL;
168 }
169
170 skb_push(skb, skb->data - skb_mac_header(skb));
171
172 return skb;
173 }
174
175 skb_list_walk_safe(skb, skb2, nskb) {
176 esp_features |= skb->dev->gso_partial_features;
177 skb_mark_not_on_list(skb2);
178
179 xo = xfrm_offload(skb2);
180 xo->flags |= XFRM_DEV_RESUME;
181
182 xfrm_outer_mode_prep(x, skb2);
183
184 err = x->type_offload->xmit(x, skb2, esp_features);
185 if (!err) {
186 skb2->next = nskb;
187 } else if (err != -EINPROGRESS) {
188 XFRM_INC_STATS(xs_net(x), LINUX_MIB_XFRMOUTSTATEPROTOERROR);
189 skb2->next = nskb;
190 kfree_skb_list(skb2);
191 return NULL;
192 } else {
193 if (skb == skb2)
194 skb = nskb;
195 else
196 pskb->next = nskb;
197
198 continue;
199 }
200
201 skb_push(skb2, skb2->data - skb_mac_header(skb2));
202 pskb = skb2;
203 }
204
205 return skb;
206}
207EXPORT_SYMBOL_GPL(validate_xmit_xfrm);
208
209int xfrm_dev_state_add(struct net *net, struct xfrm_state *x,
210 struct xfrm_user_offload *xuo)
211{
212 int err;
213 struct dst_entry *dst;
214 struct net_device *dev;
215 struct xfrm_state_offload *xso = &x->xso;
216 xfrm_address_t *saddr;
217 xfrm_address_t *daddr;
218
219 if (!x->type_offload)
220 return -EINVAL;
221
222
223 if (x->encap || x->tfcpad)
224 return -EINVAL;
225
226 dev = dev_get_by_index(net, xuo->ifindex);
227 if (!dev) {
228 if (!(xuo->flags & XFRM_OFFLOAD_INBOUND)) {
229 saddr = &x->props.saddr;
230 daddr = &x->id.daddr;
231 } else {
232 saddr = &x->id.daddr;
233 daddr = &x->props.saddr;
234 }
235
236 dst = __xfrm_dst_lookup(net, 0, 0, saddr, daddr,
237 x->props.family,
238 xfrm_smark_get(0, x));
239 if (IS_ERR(dst))
240 return 0;
241
242 dev = dst->dev;
243
244 dev_hold(dev);
245 dst_release(dst);
246 }
247
248 if (!dev->xfrmdev_ops || !dev->xfrmdev_ops->xdo_dev_state_add) {
249 xso->dev = NULL;
250 dev_put(dev);
251 return 0;
252 }
253
254 if (x->props.flags & XFRM_STATE_ESN &&
255 !dev->xfrmdev_ops->xdo_dev_state_advance_esn) {
256 xso->dev = NULL;
257 dev_put(dev);
258 return -EINVAL;
259 }
260
261 xso->dev = dev;
262 xso->real_dev = dev;
263 xso->num_exthdrs = 1;
264 xso->flags = xuo->flags;
265
266 err = dev->xfrmdev_ops->xdo_dev_state_add(x);
267 if (err) {
268 xso->num_exthdrs = 0;
269 xso->flags = 0;
270 xso->dev = NULL;
271 xso->real_dev = NULL;
272 dev_put(dev);
273
274 if (err != -EOPNOTSUPP)
275 return err;
276 }
277
278 return 0;
279}
280EXPORT_SYMBOL_GPL(xfrm_dev_state_add);
281
282bool xfrm_dev_offload_ok(struct sk_buff *skb, struct xfrm_state *x)
283{
284 int mtu;
285 struct dst_entry *dst = skb_dst(skb);
286 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
287 struct net_device *dev = x->xso.dev;
288
289 if (!x->type_offload || x->encap)
290 return false;
291
292 if ((!dev || (dev == xfrm_dst_path(dst)->dev)) &&
293 (!xdst->child->xfrm)) {
294 mtu = xfrm_state_mtu(x, xdst->child_mtu_cached);
295 if (skb->len <= mtu)
296 goto ok;
297
298 if (skb_is_gso(skb) && skb_gso_validate_network_len(skb, mtu))
299 goto ok;
300 }
301
302 return false;
303
304ok:
305 if (dev && dev->xfrmdev_ops && dev->xfrmdev_ops->xdo_dev_offload_ok)
306 return x->xso.dev->xfrmdev_ops->xdo_dev_offload_ok(skb, x);
307
308 return true;
309}
310EXPORT_SYMBOL_GPL(xfrm_dev_offload_ok);
311
312void xfrm_dev_resume(struct sk_buff *skb)
313{
314 struct net_device *dev = skb->dev;
315 int ret = NETDEV_TX_BUSY;
316 struct netdev_queue *txq;
317 struct softnet_data *sd;
318 unsigned long flags;
319
320 rcu_read_lock();
321 txq = netdev_core_pick_tx(dev, skb, NULL);
322
323 HARD_TX_LOCK(dev, txq, smp_processor_id());
324 if (!netif_xmit_frozen_or_stopped(txq))
325 skb = dev_hard_start_xmit(skb, dev, txq, &ret);
326 HARD_TX_UNLOCK(dev, txq);
327
328 if (!dev_xmit_complete(ret)) {
329 local_irq_save(flags);
330 sd = this_cpu_ptr(&softnet_data);
331 skb_queue_tail(&sd->xfrm_backlog, skb);
332 raise_softirq_irqoff(NET_TX_SOFTIRQ);
333 local_irq_restore(flags);
334 }
335 rcu_read_unlock();
336}
337EXPORT_SYMBOL_GPL(xfrm_dev_resume);
338
339void xfrm_dev_backlog(struct softnet_data *sd)
340{
341 struct sk_buff_head *xfrm_backlog = &sd->xfrm_backlog;
342 struct sk_buff_head list;
343 struct sk_buff *skb;
344
345 if (skb_queue_empty(xfrm_backlog))
346 return;
347
348 __skb_queue_head_init(&list);
349
350 spin_lock(&xfrm_backlog->lock);
351 skb_queue_splice_init(xfrm_backlog, &list);
352 spin_unlock(&xfrm_backlog->lock);
353
354 while (!skb_queue_empty(&list)) {
355 skb = __skb_dequeue(&list);
356 xfrm_dev_resume(skb);
357 }
358
359}
360#endif
361
362static int xfrm_api_check(struct net_device *dev)
363{
364#ifdef CONFIG_XFRM_OFFLOAD
365 if ((dev->features & NETIF_F_HW_ESP_TX_CSUM) &&
366 !(dev->features & NETIF_F_HW_ESP))
367 return NOTIFY_BAD;
368
369 if ((dev->features & NETIF_F_HW_ESP) &&
370 (!(dev->xfrmdev_ops &&
371 dev->xfrmdev_ops->xdo_dev_state_add &&
372 dev->xfrmdev_ops->xdo_dev_state_delete)))
373 return NOTIFY_BAD;
374#else
375 if (dev->features & (NETIF_F_HW_ESP | NETIF_F_HW_ESP_TX_CSUM))
376 return NOTIFY_BAD;
377#endif
378
379 return NOTIFY_DONE;
380}
381
382static int xfrm_dev_register(struct net_device *dev)
383{
384 return xfrm_api_check(dev);
385}
386
387static int xfrm_dev_feat_change(struct net_device *dev)
388{
389 return xfrm_api_check(dev);
390}
391
392static int xfrm_dev_down(struct net_device *dev)
393{
394 if (dev->features & NETIF_F_HW_ESP)
395 xfrm_dev_state_flush(dev_net(dev), dev, true);
396
397 return NOTIFY_DONE;
398}
399
400static int xfrm_dev_event(struct notifier_block *this, unsigned long event, void *ptr)
401{
402 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
403
404 switch (event) {
405 case NETDEV_REGISTER:
406 return xfrm_dev_register(dev);
407
408 case NETDEV_FEAT_CHANGE:
409 return xfrm_dev_feat_change(dev);
410
411 case NETDEV_DOWN:
412 case NETDEV_UNREGISTER:
413 return xfrm_dev_down(dev);
414 }
415 return NOTIFY_DONE;
416}
417
418static struct notifier_block xfrm_dev_notifier = {
419 .notifier_call = xfrm_dev_event,
420};
421
422void __init xfrm_dev_init(void)
423{
424 register_netdevice_notifier(&xfrm_dev_notifier);
425}
426
