linux/net/xfrm/xfrm_device.c
David S. Miller 2240c12d7d Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next
Steffen Klassert says:

====================
pull request (net-next): ipsec-next 2018-10-01

1) Make xfrmi_get_link_net() static to silence a sparse warning.
   From Wei Yongjun.

2) Remove a unused esph pointer definition in esp_input().
   From Haishuang Yan.

3) Allow the NIC driver to quietly refuse xfrm offload
   in case it does not support it, the SA is created
   without offload in this case.
   From Shannon Nelson.

Please pull or let me know if there are problems.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-01 22:31:17 -07:00

352 lines
7.4 KiB
C

/*
* xfrm_device.c - IPsec device offloading code.
*
* Copyright (c) 2015 secunet Security Networks AG
*
* Author:
* Steffen Klassert <steffen.klassert@secunet.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <net/dst.h>
#include <net/xfrm.h>
#include <linux/notifier.h>
#ifdef CONFIG_XFRM_OFFLOAD
struct sk_buff *validate_xmit_xfrm(struct sk_buff *skb, netdev_features_t features, bool *again)
{
int err;
unsigned long flags;
struct xfrm_state *x;
struct sk_buff *skb2;
struct softnet_data *sd;
netdev_features_t esp_features = features;
struct xfrm_offload *xo = xfrm_offload(skb);
if (!xo)
return skb;
if (!(features & NETIF_F_HW_ESP))
esp_features = features & ~(NETIF_F_SG | NETIF_F_CSUM_MASK);
x = skb->sp->xvec[skb->sp->len - 1];
if (xo->flags & XFRM_GRO || x->xso.flags & XFRM_OFFLOAD_INBOUND)
return skb;
local_irq_save(flags);
sd = this_cpu_ptr(&softnet_data);
err = !skb_queue_empty(&sd->xfrm_backlog);
local_irq_restore(flags);
if (err) {
*again = true;
return skb;
}
if (skb_is_gso(skb)) {
struct net_device *dev = skb->dev;
if (unlikely(x->xso.dev != dev)) {
struct sk_buff *segs;
/* Packet got rerouted, fixup features and segment it. */
esp_features = esp_features & ~(NETIF_F_HW_ESP
| NETIF_F_GSO_ESP);
segs = skb_gso_segment(skb, esp_features);
if (IS_ERR(segs)) {
kfree_skb(skb);
atomic_long_inc(&dev->tx_dropped);
return NULL;
} else {
consume_skb(skb);
skb = segs;
}
}
}
if (!skb->next) {
x->outer_mode->xmit(x, skb);
xo->flags |= XFRM_DEV_RESUME;
err = x->type_offload->xmit(x, skb, esp_features);
if (err) {
if (err == -EINPROGRESS)
return NULL;
XFRM_INC_STATS(xs_net(x), LINUX_MIB_XFRMOUTSTATEPROTOERROR);
kfree_skb(skb);
return NULL;
}
skb_push(skb, skb->data - skb_mac_header(skb));
return skb;
}
skb2 = skb;
do {
struct sk_buff *nskb = skb2->next;
skb_mark_not_on_list(skb2);
xo = xfrm_offload(skb2);
xo->flags |= XFRM_DEV_RESUME;
x->outer_mode->xmit(x, skb2);
err = x->type_offload->xmit(x, skb2, esp_features);
if (!err) {
skb2->next = nskb;
} else if (err != -EINPROGRESS) {
XFRM_INC_STATS(xs_net(x), LINUX_MIB_XFRMOUTSTATEPROTOERROR);
skb2->next = nskb;
kfree_skb_list(skb2);
return NULL;
} else {
if (skb == skb2)
skb = nskb;
if (!skb)
return NULL;
goto skip_push;
}
skb_push(skb2, skb2->data - skb_mac_header(skb2));
skip_push:
skb2 = nskb;
} while (skb2);
return skb;
}
EXPORT_SYMBOL_GPL(validate_xmit_xfrm);
int xfrm_dev_state_add(struct net *net, struct xfrm_state *x,
struct xfrm_user_offload *xuo)
{
int err;
struct dst_entry *dst;
struct net_device *dev;
struct xfrm_state_offload *xso = &x->xso;
xfrm_address_t *saddr;
xfrm_address_t *daddr;
if (!x->type_offload)
return -EINVAL;
/* We don't yet support UDP encapsulation and TFC padding. */
if (x->encap || x->tfcpad)
return -EINVAL;
dev = dev_get_by_index(net, xuo->ifindex);
if (!dev) {
if (!(xuo->flags & XFRM_OFFLOAD_INBOUND)) {
saddr = &x->props.saddr;
daddr = &x->id.daddr;
} else {
saddr = &x->id.daddr;
daddr = &x->props.saddr;
}
dst = __xfrm_dst_lookup(net, 0, 0, saddr, daddr,
x->props.family,
xfrm_smark_get(0, x));
if (IS_ERR(dst))
return 0;
dev = dst->dev;
dev_hold(dev);
dst_release(dst);
}
if (!dev->xfrmdev_ops || !dev->xfrmdev_ops->xdo_dev_state_add) {
xso->dev = NULL;
dev_put(dev);
return 0;
}
if (x->props.flags & XFRM_STATE_ESN &&
!dev->xfrmdev_ops->xdo_dev_state_advance_esn) {
xso->dev = NULL;
dev_put(dev);
return -EINVAL;
}
xso->dev = dev;
xso->num_exthdrs = 1;
xso->flags = xuo->flags;
err = dev->xfrmdev_ops->xdo_dev_state_add(x);
if (err) {
xso->num_exthdrs = 0;
xso->flags = 0;
xso->dev = NULL;
dev_put(dev);
if (err != -EOPNOTSUPP)
return err;
}
return 0;
}
EXPORT_SYMBOL_GPL(xfrm_dev_state_add);
bool xfrm_dev_offload_ok(struct sk_buff *skb, struct xfrm_state *x)
{
int mtu;
struct dst_entry *dst = skb_dst(skb);
struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
struct net_device *dev = x->xso.dev;
if (!x->type_offload || x->encap)
return false;
if ((!dev || (dev == xfrm_dst_path(dst)->dev)) &&
(!xdst->child->xfrm && x->type->get_mtu)) {
mtu = x->type->get_mtu(x, xdst->child_mtu_cached);
if (skb->len <= mtu)
goto ok;
if (skb_is_gso(skb) && skb_gso_validate_network_len(skb, mtu))
goto ok;
}
return false;
ok:
if (dev && dev->xfrmdev_ops && dev->xfrmdev_ops->xdo_dev_offload_ok)
return x->xso.dev->xfrmdev_ops->xdo_dev_offload_ok(skb, x);
return true;
}
EXPORT_SYMBOL_GPL(xfrm_dev_offload_ok);
void xfrm_dev_resume(struct sk_buff *skb)
{
struct net_device *dev = skb->dev;
int ret = NETDEV_TX_BUSY;
struct netdev_queue *txq;
struct softnet_data *sd;
unsigned long flags;
rcu_read_lock();
txq = netdev_pick_tx(dev, skb, NULL);
HARD_TX_LOCK(dev, txq, smp_processor_id());
if (!netif_xmit_frozen_or_stopped(txq))
skb = dev_hard_start_xmit(skb, dev, txq, &ret);
HARD_TX_UNLOCK(dev, txq);
if (!dev_xmit_complete(ret)) {
local_irq_save(flags);
sd = this_cpu_ptr(&softnet_data);
skb_queue_tail(&sd->xfrm_backlog, skb);
raise_softirq_irqoff(NET_TX_SOFTIRQ);
local_irq_restore(flags);
}
rcu_read_unlock();
}
EXPORT_SYMBOL_GPL(xfrm_dev_resume);
void xfrm_dev_backlog(struct softnet_data *sd)
{
struct sk_buff_head *xfrm_backlog = &sd->xfrm_backlog;
struct sk_buff_head list;
struct sk_buff *skb;
if (skb_queue_empty(xfrm_backlog))
return;
__skb_queue_head_init(&list);
spin_lock(&xfrm_backlog->lock);
skb_queue_splice_init(xfrm_backlog, &list);
spin_unlock(&xfrm_backlog->lock);
while (!skb_queue_empty(&list)) {
skb = __skb_dequeue(&list);
xfrm_dev_resume(skb);
}
}
#endif
static int xfrm_api_check(struct net_device *dev)
{
#ifdef CONFIG_XFRM_OFFLOAD
if ((dev->features & NETIF_F_HW_ESP_TX_CSUM) &&
!(dev->features & NETIF_F_HW_ESP))
return NOTIFY_BAD;
if ((dev->features & NETIF_F_HW_ESP) &&
(!(dev->xfrmdev_ops &&
dev->xfrmdev_ops->xdo_dev_state_add &&
dev->xfrmdev_ops->xdo_dev_state_delete)))
return NOTIFY_BAD;
#else
if (dev->features & (NETIF_F_HW_ESP | NETIF_F_HW_ESP_TX_CSUM))
return NOTIFY_BAD;
#endif
return NOTIFY_DONE;
}
static int xfrm_dev_register(struct net_device *dev)
{
return xfrm_api_check(dev);
}
static int xfrm_dev_feat_change(struct net_device *dev)
{
return xfrm_api_check(dev);
}
static int xfrm_dev_down(struct net_device *dev)
{
if (dev->features & NETIF_F_HW_ESP)
xfrm_dev_state_flush(dev_net(dev), dev, true);
return NOTIFY_DONE;
}
static int xfrm_dev_event(struct notifier_block *this, unsigned long event, void *ptr)
{
struct net_device *dev = netdev_notifier_info_to_dev(ptr);
switch (event) {
case NETDEV_REGISTER:
return xfrm_dev_register(dev);
case NETDEV_FEAT_CHANGE:
return xfrm_dev_feat_change(dev);
case NETDEV_DOWN:
return xfrm_dev_down(dev);
}
return NOTIFY_DONE;
}
static struct notifier_block xfrm_dev_notifier = {
.notifier_call = xfrm_dev_event,
};
void __init xfrm_dev_init(void)
{
register_netdevice_notifier(&xfrm_dev_notifier);
}