gre6: Cleanup GREv6 receive path, call common GRE functions

- Create gre_rcv function. This calls gre_parse_header and ip6gre_rcv.
  - Call ip6_tnl_rcv. Doing this and using gre_parse_header eliminates
    most of the code in ip6gre_rcv.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Tom Herbert 2016-04-29 17:12:17 -07:00 committed by David S. Miller
parent 95f5c64c3c
commit 308edfdf15

View File

@ -54,6 +54,7 @@
#include <net/ip6_fib.h>
#include <net/ip6_route.h>
#include <net/ip6_tunnel.h>
#include <net/gre.h>
static bool log_ecn_error = true;
@ -443,137 +444,40 @@ static void ip6gre_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
t->err_time = jiffies;
}
static int ip6gre_rcv(struct sk_buff *skb)
static int ip6gre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi)
{
const struct ipv6hdr *ipv6h;
u8 *h;
__be16 flags;
__sum16 csum = 0;
__be32 key = 0;
u32 seqno = 0;
struct ip6_tnl *tunnel;
int offset = 4;
__be16 gre_proto;
int err;
if (!pskb_may_pull(skb, sizeof(struct in6_addr)))
goto drop;
ipv6h = ipv6_hdr(skb);
h = skb->data;
flags = *(__be16 *)h;
if (flags&(GRE_CSUM|GRE_KEY|GRE_ROUTING|GRE_SEQ|GRE_VERSION)) {
/* - Version must be 0.
- We do not support routing headers.
*/
if (flags&(GRE_VERSION|GRE_ROUTING))
goto drop;
if (flags&GRE_CSUM) {
csum = skb_checksum_simple_validate(skb);
offset += 4;
}
if (flags&GRE_KEY) {
key = *(__be32 *)(h + offset);
offset += 4;
}
if (flags&GRE_SEQ) {
seqno = ntohl(*(__be32 *)(h + offset));
offset += 4;
}
}
gre_proto = *(__be16 *)(h + 2);
tunnel = ip6gre_tunnel_lookup(skb->dev,
&ipv6h->saddr, &ipv6h->daddr, key,
gre_proto);
&ipv6h->saddr, &ipv6h->daddr, tpi->key,
tpi->proto);
if (tunnel) {
struct pcpu_sw_netstats *tstats;
ip6_tnl_rcv(tunnel, skb, tpi, NULL, false);
if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
goto drop;
if (!ip6_tnl_rcv_ctl(tunnel, &ipv6h->daddr, &ipv6h->saddr)) {
tunnel->dev->stats.rx_dropped++;
goto drop;
}
skb->protocol = gre_proto;
/* WCCP version 1 and 2 protocol decoding.
* - Change protocol to IPv6
* - When dealing with WCCPv2, Skip extra 4 bytes in GRE header
*/
if (flags == 0 && gre_proto == htons(ETH_P_WCCP)) {
skb->protocol = htons(ETH_P_IPV6);
if ((*(h + offset) & 0xF0) != 0x40)
offset += 4;
}
skb->mac_header = skb->network_header;
__pskb_pull(skb, offset);
skb_postpull_rcsum(skb, skb_transport_header(skb), offset);
if (((flags&GRE_CSUM) && csum) ||
(!(flags&GRE_CSUM) && tunnel->parms.i_flags&GRE_CSUM)) {
tunnel->dev->stats.rx_crc_errors++;
tunnel->dev->stats.rx_errors++;
goto drop;
}
if (tunnel->parms.i_flags&GRE_SEQ) {
if (!(flags&GRE_SEQ) ||
(tunnel->i_seqno &&
(s32)(seqno - tunnel->i_seqno) < 0)) {
tunnel->dev->stats.rx_fifo_errors++;
tunnel->dev->stats.rx_errors++;
goto drop;
}
tunnel->i_seqno = seqno + 1;
}
/* Warning: All skb pointers will be invalidated! */
if (tunnel->dev->type == ARPHRD_ETHER) {
if (!pskb_may_pull(skb, ETH_HLEN)) {
tunnel->dev->stats.rx_length_errors++;
tunnel->dev->stats.rx_errors++;
goto drop;
}
ipv6h = ipv6_hdr(skb);
skb->protocol = eth_type_trans(skb, tunnel->dev);
skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
}
__skb_tunnel_rx(skb, tunnel->dev, tunnel->net);
skb_reset_network_header(skb);
err = IP6_ECN_decapsulate(ipv6h, skb);
if (unlikely(err)) {
if (log_ecn_error)
net_info_ratelimited("non-ECT from %pI6 with dsfield=%#x\n",
&ipv6h->saddr,
ipv6_get_dsfield(ipv6h));
if (err > 1) {
++tunnel->dev->stats.rx_frame_errors;
++tunnel->dev->stats.rx_errors;
goto drop;
}
}
tstats = this_cpu_ptr(tunnel->dev->tstats);
u64_stats_update_begin(&tstats->syncp);
tstats->rx_packets++;
tstats->rx_bytes += skb->len;
u64_stats_update_end(&tstats->syncp);
netif_rx(skb);
return 0;
return PACKET_RCVD;
}
icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
return PACKET_REJECT;
}
static int gre_rcv(struct sk_buff *skb)
{
struct tnl_ptk_info tpi;
bool csum_err = false;
int hdr_len;
if (gre_parse_header(skb, &tpi, &csum_err, &hdr_len) < 0)
goto drop;
if (iptunnel_pull_header(skb, hdr_len, tpi.proto, false))
goto drop;
if (ip6gre_rcv(skb, &tpi) == PACKET_RCVD)
return 0;
icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
drop:
kfree_skb(skb);
return 0;
@ -1075,6 +979,8 @@ static int ip6gre_tunnel_ioctl(struct net_device *dev,
struct net *net = t->net;
struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
memset(&p1, 0, sizeof(p1));
switch (cmd) {
case SIOCGETTUNNEL:
if (dev == ign->fb_tunnel_dev) {
@ -1318,7 +1224,7 @@ static void ip6gre_fb_tunnel_init(struct net_device *dev)
static struct inet6_protocol ip6gre_protocol __read_mostly = {
.handler = ip6gre_rcv,
.handler = gre_rcv,
.err_handler = ip6gre_err,
.flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
};