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 static void __xfrm_mode_beet_prep(struct xfrm_state *x, struct sk_buff *skb,
50 struct xfrm_offload *xo = xfrm_offload(skb);
53 if (xo->flags & XFRM_GSO_SEGMENT)
54 skb->transport_header = skb->network_header + hsize;
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);
63 pskb_pull(skb, skb->mac_len + hsize + (x->props.header_len - phlen));
66 /* Adjust pointers into the packet when IPsec is done at layer2 */
67 static void xfrm_outer_mode_prep(struct xfrm_state *x, struct sk_buff *skb)
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));
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));
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));
94 case XFRM_MODE_ROUTEOPTIMIZATION:
95 case XFRM_MODE_IN_TRIGGER:
100 struct sk_buff *validate_xmit_xfrm(struct sk_buff *skb, netdev_features_t features, bool *again)
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;
112 if (!xo || (xo->flags & XFRM_XMIT))
115 if (!(features & NETIF_F_HW_ESP))
116 esp_features = features & ~(NETIF_F_SG | NETIF_F_CSUM_MASK);
118 sp = skb_sec_path(skb);
119 x = sp->xvec[sp->len - 1];
120 if (xo->flags & XFRM_GRO || x->xso.dir == XFRM_DEV_OFFLOAD_IN)
123 /* This skb was already validated on the upper/virtual dev */
124 if ((x->xso.dev != dev) && (x->xso.real_dev == dev))
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);
137 if (skb_is_gso(skb) && unlikely(x->xso.dev != dev)) {
138 struct sk_buff *segs;
140 /* Packet got rerouted, fixup features and segment it. */
141 esp_features = esp_features & ~(NETIF_F_HW_ESP | NETIF_F_GSO_ESP);
143 segs = skb_gso_segment(skb, esp_features);
146 dev_core_stats_tx_dropped_inc(dev);
155 esp_features |= skb->dev->gso_partial_features;
156 xfrm_outer_mode_prep(x, skb);
158 xo->flags |= XFRM_DEV_RESUME;
160 err = x->type_offload->xmit(x, skb, esp_features);
162 if (err == -EINPROGRESS)
165 XFRM_INC_STATS(xs_net(x), LINUX_MIB_XFRMOUTSTATEPROTOERROR);
170 skb_push(skb, skb->data - skb_mac_header(skb));
175 skb_list_walk_safe(skb, skb2, nskb) {
176 esp_features |= skb->dev->gso_partial_features;
177 skb_mark_not_on_list(skb2);
179 xo = xfrm_offload(skb2);
180 xo->flags |= XFRM_DEV_RESUME;
182 xfrm_outer_mode_prep(x, skb2);
184 err = x->type_offload->xmit(x, skb2, esp_features);
187 } else if (err != -EINPROGRESS) {
188 XFRM_INC_STATS(xs_net(x), LINUX_MIB_XFRMOUTSTATEPROTOERROR);
190 kfree_skb_list(skb2);
201 skb_push(skb2, skb2->data - skb_mac_header(skb2));
207 EXPORT_SYMBOL_GPL(validate_xmit_xfrm);
209 int xfrm_dev_state_add(struct net *net, struct xfrm_state *x,
210 struct xfrm_user_offload *xuo,
211 struct netlink_ext_ack *extack)
214 struct dst_entry *dst;
215 struct net_device *dev;
216 struct xfrm_dev_offload *xso = &x->xso;
217 xfrm_address_t *saddr;
218 xfrm_address_t *daddr;
220 if (!x->type_offload) {
221 NL_SET_ERR_MSG(extack, "Type doesn't support offload");
225 /* We don't yet support UDP encapsulation and TFC padding. */
226 if (x->encap || x->tfcpad) {
227 NL_SET_ERR_MSG(extack, "Encapsulation and TFC padding can't be offloaded");
231 if (xuo->flags & ~(XFRM_OFFLOAD_IPV6 | XFRM_OFFLOAD_INBOUND)) {
232 NL_SET_ERR_MSG(extack, "Unrecognized flags in offload request");
236 dev = dev_get_by_index(net, xuo->ifindex);
238 if (!(xuo->flags & XFRM_OFFLOAD_INBOUND)) {
239 saddr = &x->props.saddr;
240 daddr = &x->id.daddr;
242 saddr = &x->id.daddr;
243 daddr = &x->props.saddr;
246 dst = __xfrm_dst_lookup(net, 0, 0, saddr, daddr,
248 xfrm_smark_get(0, x));
258 if (!dev->xfrmdev_ops || !dev->xfrmdev_ops->xdo_dev_state_add) {
264 if (x->props.flags & XFRM_STATE_ESN &&
265 !dev->xfrmdev_ops->xdo_dev_state_advance_esn) {
266 NL_SET_ERR_MSG(extack, "Device doesn't support offload with ESN");
273 netdev_tracker_alloc(dev, &xso->dev_tracker, GFP_ATOMIC);
276 if (xuo->flags & XFRM_OFFLOAD_INBOUND)
277 xso->dir = XFRM_DEV_OFFLOAD_IN;
279 xso->dir = XFRM_DEV_OFFLOAD_OUT;
281 err = dev->xfrmdev_ops->xdo_dev_state_add(x);
285 xso->real_dev = NULL;
286 netdev_put(dev, &xso->dev_tracker);
288 if (err != -EOPNOTSUPP) {
289 NL_SET_ERR_MSG(extack, "Device failed to offload this state");
296 EXPORT_SYMBOL_GPL(xfrm_dev_state_add);
298 bool xfrm_dev_offload_ok(struct sk_buff *skb, struct xfrm_state *x)
301 struct dst_entry *dst = skb_dst(skb);
302 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
303 struct net_device *dev = x->xso.dev;
305 if (!x->type_offload || x->encap)
308 if ((!dev || (dev == xfrm_dst_path(dst)->dev)) &&
309 (!xdst->child->xfrm)) {
310 mtu = xfrm_state_mtu(x, xdst->child_mtu_cached);
314 if (skb_is_gso(skb) && skb_gso_validate_network_len(skb, mtu))
321 if (dev && dev->xfrmdev_ops && dev->xfrmdev_ops->xdo_dev_offload_ok)
322 return x->xso.dev->xfrmdev_ops->xdo_dev_offload_ok(skb, x);
326 EXPORT_SYMBOL_GPL(xfrm_dev_offload_ok);
328 void xfrm_dev_resume(struct sk_buff *skb)
330 struct net_device *dev = skb->dev;
331 int ret = NETDEV_TX_BUSY;
332 struct netdev_queue *txq;
333 struct softnet_data *sd;
337 txq = netdev_core_pick_tx(dev, skb, NULL);
339 HARD_TX_LOCK(dev, txq, smp_processor_id());
340 if (!netif_xmit_frozen_or_stopped(txq))
341 skb = dev_hard_start_xmit(skb, dev, txq, &ret);
342 HARD_TX_UNLOCK(dev, txq);
344 if (!dev_xmit_complete(ret)) {
345 local_irq_save(flags);
346 sd = this_cpu_ptr(&softnet_data);
347 skb_queue_tail(&sd->xfrm_backlog, skb);
348 raise_softirq_irqoff(NET_TX_SOFTIRQ);
349 local_irq_restore(flags);
353 EXPORT_SYMBOL_GPL(xfrm_dev_resume);
355 void xfrm_dev_backlog(struct softnet_data *sd)
357 struct sk_buff_head *xfrm_backlog = &sd->xfrm_backlog;
358 struct sk_buff_head list;
361 if (skb_queue_empty(xfrm_backlog))
364 __skb_queue_head_init(&list);
366 spin_lock(&xfrm_backlog->lock);
367 skb_queue_splice_init(xfrm_backlog, &list);
368 spin_unlock(&xfrm_backlog->lock);
370 while (!skb_queue_empty(&list)) {
371 skb = __skb_dequeue(&list);
372 xfrm_dev_resume(skb);
378 static int xfrm_api_check(struct net_device *dev)
380 #ifdef CONFIG_XFRM_OFFLOAD
381 if ((dev->features & NETIF_F_HW_ESP_TX_CSUM) &&
382 !(dev->features & NETIF_F_HW_ESP))
385 if ((dev->features & NETIF_F_HW_ESP) &&
386 (!(dev->xfrmdev_ops &&
387 dev->xfrmdev_ops->xdo_dev_state_add &&
388 dev->xfrmdev_ops->xdo_dev_state_delete)))
391 if (dev->features & (NETIF_F_HW_ESP | NETIF_F_HW_ESP_TX_CSUM))
398 static int xfrm_dev_down(struct net_device *dev)
400 if (dev->features & NETIF_F_HW_ESP)
401 xfrm_dev_state_flush(dev_net(dev), dev, true);
406 static int xfrm_dev_event(struct notifier_block *this, unsigned long event, void *ptr)
408 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
411 case NETDEV_REGISTER:
412 return xfrm_api_check(dev);
414 case NETDEV_FEAT_CHANGE:
415 return xfrm_api_check(dev);
418 case NETDEV_UNREGISTER:
419 return xfrm_dev_down(dev);
424 static struct notifier_block xfrm_dev_notifier = {
425 .notifier_call = xfrm_dev_event,
428 void __init xfrm_dev_init(void)
430 register_netdevice_notifier(&xfrm_dev_notifier);