gre: Restructure tunneling.

[sliver-openvswitch.git] / datapath / linux / compat / gso.c

diff --git a/datapath/linux/compat/gso.c b/datapath/linux/compat/gso.c
new file mode 100644 (file)
index 0000000..7379a57
--- /dev/null
+++ b/datapath/linux/compat/gso.c
@@ -0,0 +1,146 @@
+/*
+ * Copyright (c) 2007-2013 Nicira, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA
+ */
+
+#include <linux/module.h>
+#include <linux/if.h>
+#include <linux/if_tunnel.h>
+#include <linux/icmp.h>
+#include <linux/in.h>
+#include <linux/ip.h>
+#include <linux/kernel.h>
+#include <linux/kmod.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+#include <linux/spinlock.h>
+
+#include <net/gre.h>
+#include <net/icmp.h>
+#include <net/protocol.h>
+#include <net/route.h>
+#include <net/xfrm.h>
+
+#include "gso.h"
+
+static __be16 skb_network_protocol(struct sk_buff *skb)
+{
+       __be16 type = skb->protocol;
+       int vlan_depth = ETH_HLEN;
+
+       while (type == htons(ETH_P_8021Q) || type == htons(ETH_P_8021AD)) {
+               struct vlan_hdr *vh;
+
+               if (unlikely(!pskb_may_pull(skb, vlan_depth + VLAN_HLEN)))
+                       return 0;
+
+               vh = (struct vlan_hdr *)(skb->data + vlan_depth);
+               type = vh->h_vlan_encapsulated_proto;
+               vlan_depth += VLAN_HLEN;
+       }
+
+       return type;
+}
+
+static struct sk_buff *tnl_skb_gso_segment(struct sk_buff *skb,
+                                          netdev_features_t features,
+                                          bool tx_path)
+{
+       struct iphdr *iph = ip_hdr(skb);
+       int pkt_hlen = skb_inner_network_offset(skb); /* inner l2 + tunnel hdr. */
+       int mac_offset = skb_inner_mac_offset(skb);
+       struct sk_buff *skb1 = skb;
+       struct sk_buff *segs;
+       __be16 proto = skb->protocol;
+
+       /* setup whole inner packet to get protocol. */
+       __skb_pull(skb, mac_offset);
+       skb->protocol = skb_network_protocol(skb);
+
+       /* setup l3 packet to gso, to get around segmentation bug on older kernel.*/
+       __skb_pull(skb, (pkt_hlen - mac_offset));
+       skb_reset_mac_header(skb);
+       skb_reset_network_header(skb);
+       skb_reset_transport_header(skb);
+
+       segs = __skb_gso_segment(skb, 0, tx_path);
+       if (!segs || IS_ERR(segs))
+               goto free;
+
+       skb = segs;
+       while (skb) {
+               __skb_push(skb, pkt_hlen);
+               skb_reset_mac_header(skb);
+               skb_reset_network_header(skb);
+               skb_set_transport_header(skb, sizeof(struct iphdr));
+               skb->mac_len = 0;
+
+               memcpy(ip_hdr(skb), iph, pkt_hlen);
+               if (OVS_GSO_CB(skb)->fix_segment)
+                       OVS_GSO_CB(skb)->fix_segment(skb);
+
+               skb->protocol = proto;
+               skb = skb->next;
+       }
+free:
+       consume_skb(skb1);
+       return segs;
+}
+
+int rpl_ip_local_out(struct sk_buff *skb)
+{
+       int ret = NETDEV_TX_OK;
+       int id;
+
+       if (skb_is_gso(skb)) {
+               struct iphdr *iph;
+
+               iph = ip_hdr(skb);
+               id = ntohs(iph->id);
+               skb = tnl_skb_gso_segment(skb, 0, false);
+               if (!skb || IS_ERR(skb))
+                       return 0;
+       }  else if (skb->ip_summed == CHECKSUM_PARTIAL) {
+               int err;
+
+               err = skb_checksum_help(skb);
+               if (unlikely(err))
+                       return 0;
+               id = -1;
+       }
+
+       while (skb) {
+               struct sk_buff *next_skb = skb->next;
+               struct iphdr *iph;
+               int err;
+
+               skb->next = NULL;
+
+               iph = ip_hdr(skb);
+               if (id >= 0)
+                       iph->id = htons(id++);
+
+               memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
+
+#undef ip_local_out
+               err = ip_local_out(skb);
+               if (unlikely(net_xmit_eval(err)))
+                       ret = err;
+
+               skb = next_skb;
+       }
+       return ret;
+}