diff options
Diffstat (limited to 'net/xfrm/xfrm_device.c')
| -rw-r--r-- | net/xfrm/xfrm_device.c | 208 |
1 files changed, 208 insertions, 0 deletions
diff --git a/net/xfrm/xfrm_device.c b/net/xfrm/xfrm_device.c new file mode 100644 index 000000000000..8ec8a3fcf8d4 --- /dev/null +++ b/net/xfrm/xfrm_device.c @@ -0,0 +1,208 @@ +/* + * 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> + +int validate_xmit_xfrm(struct sk_buff *skb, netdev_features_t features) +{ + int err; + struct xfrm_state *x; + struct xfrm_offload *xo = xfrm_offload(skb); + + if (skb_is_gso(skb)) + return 0; + + if (xo) { + x = skb->sp->xvec[skb->sp->len - 1]; + if (xo->flags & XFRM_GRO || x->xso.flags & XFRM_OFFLOAD_INBOUND) + return 0; + + x->outer_mode->xmit(x, skb); + + err = x->type_offload->xmit(x, skb, features); + if (err) { + XFRM_INC_STATS(xs_net(x), LINUX_MIB_XFRMOUTSTATEPROTOERROR); + return err; + } + + skb_push(skb, skb->data - skb_mac_header(skb)); + } + + return 0; +} +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 0; + + /* We don't yet support UDP encapsulation, TFC padding and ESN. */ + if (x->encap || x->tfcpad || (x->props.flags & XFRM_STATE_ESN)) + return 0; + + 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); + 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) { + dev_put(dev); + return 0; + } + + xso->dev = dev; + xso->num_exthdrs = 1; + xso->flags = xuo->flags; + + err = dev->xfrmdev_ops->xdo_dev_state_add(x); + if (err) { + dev_put(dev); + 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 ((x->xso.offload_handle && (dev == dst->path->dev)) && + !dst->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_mtu(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); + +int xfrm_dev_register(struct net_device *dev) +{ + if ((dev->features & NETIF_F_HW_ESP) && !dev->xfrmdev_ops) + return NOTIFY_BAD; + if ((dev->features & NETIF_F_HW_ESP_TX_CSUM) && + !(dev->features & NETIF_F_HW_ESP)) + return NOTIFY_BAD; + + return NOTIFY_DONE; +} + +static int xfrm_dev_unregister(struct net_device *dev) +{ + return NOTIFY_DONE; +} + +static int xfrm_dev_feat_change(struct net_device *dev) +{ + if ((dev->features & NETIF_F_HW_ESP) && !dev->xfrmdev_ops) + return NOTIFY_BAD; + else if (!(dev->features & NETIF_F_HW_ESP)) + dev->xfrmdev_ops = NULL; + + if ((dev->features & NETIF_F_HW_ESP_TX_CSUM) && + !(dev->features & NETIF_F_HW_ESP)) + return NOTIFY_BAD; + + return NOTIFY_DONE; +} + +static int xfrm_dev_down(struct net_device *dev) +{ + if (dev->hw_features & NETIF_F_HW_ESP) + xfrm_dev_state_flush(dev_net(dev), dev, true); + + xfrm_garbage_collect(dev_net(dev)); + + 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_UNREGISTER: + return xfrm_dev_unregister(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 __net_init xfrm_dev_init(void) +{ + register_netdevice_notifier(&xfrm_dev_notifier); +} |