153 lines
3.8 KiB
C
153 lines
3.8 KiB
C
// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
|
|
#include <linux/if_vlan.h>
|
|
#include <net/netlink.h>
|
|
#include <net/sch_generic.h>
|
|
#include <net/pkt_sched.h>
|
|
#include <net/dst.h>
|
|
#include <net/ip.h>
|
|
#include <net/ip6_fib.h>
|
|
|
|
struct sch_frag_data {
|
|
unsigned long dst;
|
|
struct qdisc_skb_cb cb;
|
|
__be16 inner_protocol;
|
|
u16 vlan_tci;
|
|
__be16 vlan_proto;
|
|
unsigned int l2_len;
|
|
u8 l2_data[VLAN_ETH_HLEN];
|
|
int (*xmit)(struct sk_buff *skb);
|
|
};
|
|
|
|
static DEFINE_PER_CPU(struct sch_frag_data, sch_frag_data_storage);
|
|
|
|
static int sch_frag_xmit(struct net *net, struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
struct sch_frag_data *data = this_cpu_ptr(&sch_frag_data_storage);
|
|
|
|
if (skb_cow_head(skb, data->l2_len) < 0) {
|
|
kfree_skb(skb);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
__skb_dst_copy(skb, data->dst);
|
|
*qdisc_skb_cb(skb) = data->cb;
|
|
skb->inner_protocol = data->inner_protocol;
|
|
if (data->vlan_tci & VLAN_CFI_MASK)
|
|
__vlan_hwaccel_put_tag(skb, data->vlan_proto,
|
|
data->vlan_tci & ~VLAN_CFI_MASK);
|
|
else
|
|
__vlan_hwaccel_clear_tag(skb);
|
|
|
|
/* Reconstruct the MAC header. */
|
|
skb_push(skb, data->l2_len);
|
|
memcpy(skb->data, &data->l2_data, data->l2_len);
|
|
skb_postpush_rcsum(skb, skb->data, data->l2_len);
|
|
skb_reset_mac_header(skb);
|
|
|
|
return data->xmit(skb);
|
|
}
|
|
|
|
static void sch_frag_prepare_frag(struct sk_buff *skb,
|
|
int (*xmit)(struct sk_buff *skb))
|
|
{
|
|
unsigned int hlen = skb_network_offset(skb);
|
|
struct sch_frag_data *data;
|
|
|
|
data = this_cpu_ptr(&sch_frag_data_storage);
|
|
data->dst = skb->_skb_refdst;
|
|
data->cb = *qdisc_skb_cb(skb);
|
|
data->xmit = xmit;
|
|
data->inner_protocol = skb->inner_protocol;
|
|
if (skb_vlan_tag_present(skb))
|
|
data->vlan_tci = skb_vlan_tag_get(skb) | VLAN_CFI_MASK;
|
|
else
|
|
data->vlan_tci = 0;
|
|
data->vlan_proto = skb->vlan_proto;
|
|
data->l2_len = hlen;
|
|
memcpy(&data->l2_data, skb->data, hlen);
|
|
|
|
memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
|
|
skb_pull(skb, hlen);
|
|
}
|
|
|
|
static unsigned int
|
|
sch_frag_dst_get_mtu(const struct dst_entry *dst)
|
|
{
|
|
return dst->dev->mtu;
|
|
}
|
|
|
|
static struct dst_ops sch_frag_dst_ops = {
|
|
.family = AF_UNSPEC,
|
|
.mtu = sch_frag_dst_get_mtu,
|
|
};
|
|
|
|
static int sch_fragment(struct net *net, struct sk_buff *skb,
|
|
u16 mru, int (*xmit)(struct sk_buff *skb))
|
|
{
|
|
int ret = -1;
|
|
|
|
if (skb_network_offset(skb) > VLAN_ETH_HLEN) {
|
|
net_warn_ratelimited("L2 header too long to fragment\n");
|
|
goto err;
|
|
}
|
|
|
|
if (skb_protocol(skb, true) == htons(ETH_P_IP)) {
|
|
struct rtable sch_frag_rt = { 0 };
|
|
unsigned long orig_dst;
|
|
|
|
sch_frag_prepare_frag(skb, xmit);
|
|
dst_init(&sch_frag_rt.dst, &sch_frag_dst_ops, NULL, 1,
|
|
DST_OBSOLETE_NONE, DST_NOCOUNT);
|
|
sch_frag_rt.dst.dev = skb->dev;
|
|
|
|
orig_dst = skb->_skb_refdst;
|
|
skb_dst_set_noref(skb, &sch_frag_rt.dst);
|
|
IPCB(skb)->frag_max_size = mru;
|
|
|
|
ret = ip_do_fragment(net, skb->sk, skb, sch_frag_xmit);
|
|
refdst_drop(orig_dst);
|
|
} else if (skb_protocol(skb, true) == htons(ETH_P_IPV6)) {
|
|
unsigned long orig_dst;
|
|
struct rt6_info sch_frag_rt;
|
|
|
|
sch_frag_prepare_frag(skb, xmit);
|
|
memset(&sch_frag_rt, 0, sizeof(sch_frag_rt));
|
|
dst_init(&sch_frag_rt.dst, &sch_frag_dst_ops, NULL, 1,
|
|
DST_OBSOLETE_NONE, DST_NOCOUNT);
|
|
sch_frag_rt.dst.dev = skb->dev;
|
|
|
|
orig_dst = skb->_skb_refdst;
|
|
skb_dst_set_noref(skb, &sch_frag_rt.dst);
|
|
IP6CB(skb)->frag_max_size = mru;
|
|
|
|
ret = ipv6_stub->ipv6_fragment(net, skb->sk, skb,
|
|
sch_frag_xmit);
|
|
refdst_drop(orig_dst);
|
|
} else {
|
|
net_warn_ratelimited("Fail frag %s: eth=%x, MRU=%d, MTU=%d\n",
|
|
netdev_name(skb->dev),
|
|
ntohs(skb_protocol(skb, true)), mru,
|
|
skb->dev->mtu);
|
|
goto err;
|
|
}
|
|
|
|
return ret;
|
|
err:
|
|
kfree_skb(skb);
|
|
return ret;
|
|
}
|
|
|
|
int sch_frag_xmit_hook(struct sk_buff *skb, int (*xmit)(struct sk_buff *skb))
|
|
{
|
|
u16 mru = tc_skb_cb(skb)->mru;
|
|
int err;
|
|
|
|
if (mru && skb->len > mru + skb->dev->hard_header_len)
|
|
err = sch_fragment(dev_net(skb->dev), skb, mru, xmit);
|
|
else
|
|
err = xmit(skb);
|
|
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL_GPL(sch_frag_xmit_hook);
|