From e1a8000228e16212c93b23cfbed4d622e2ec7a6b Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Thu, 9 Oct 2008 12:00:17 -0700 Subject: gre: Add Transparent Ethernet Bridging This patch adds support for Ethernet over GRE encapsulation. This is exposed to user-space with a new link type of "gretap" instead of "gre". It will create an ARPHRD_ETHER device in lieu of the usual ARPHRD_IPGRE. Note that to preserver backwards compatibility all Transparent Ethernet Bridging packets are passed to an ARPHRD_IPGRE tunnel if its key matches and there is no ARPHRD_ETHER device whose key matches more closely. Signed-off-by: Herbert Xu Signed-off-by: David S. Miller --- net/ipv4/ip_gre.c | 206 +++++++++++++++++++++++++++++++++++++++++++++--------- 1 file changed, 174 insertions(+), 32 deletions(-) (limited to 'net') diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c index 25d2c77a7f38..44ed9487fa15 100644 --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -27,6 +27,7 @@ #include #include #include +#include #include #include @@ -166,38 +167,64 @@ static DEFINE_RWLOCK(ipgre_lock); /* Given src, dst and key, find appropriate for input tunnel. */ static struct ip_tunnel * ipgre_tunnel_lookup(struct net *net, - __be32 remote, __be32 local, __be32 key) + __be32 remote, __be32 local, + __be32 key, __be16 gre_proto) { unsigned h0 = HASH(remote); unsigned h1 = HASH(key); struct ip_tunnel *t; + struct ip_tunnel *t2 = NULL; struct ipgre_net *ign = net_generic(net, ipgre_net_id); + int dev_type = (gre_proto == htons(ETH_P_TEB)) ? + ARPHRD_ETHER : ARPHRD_IPGRE; for (t = ign->tunnels_r_l[h0^h1]; t; t = t->next) { if (local == t->parms.iph.saddr && remote == t->parms.iph.daddr) { - if (t->parms.i_key == key && (t->dev->flags&IFF_UP)) - return t; + if (t->parms.i_key == key && t->dev->flags & IFF_UP) { + if (t->dev->type == dev_type) + return t; + if (t->dev->type == ARPHRD_IPGRE && !t2) + t2 = t; + } } } + for (t = ign->tunnels_r[h0^h1]; t; t = t->next) { if (remote == t->parms.iph.daddr) { - if (t->parms.i_key == key && (t->dev->flags&IFF_UP)) - return t; + if (t->parms.i_key == key && t->dev->flags & IFF_UP) { + if (t->dev->type == dev_type) + return t; + if (t->dev->type == ARPHRD_IPGRE && !t2) + t2 = t; + } } } + for (t = ign->tunnels_l[h1]; t; t = t->next) { if (local == t->parms.iph.saddr || (local == t->parms.iph.daddr && ipv4_is_multicast(local))) { - if (t->parms.i_key == key && (t->dev->flags&IFF_UP)) - return t; + if (t->parms.i_key == key && t->dev->flags & IFF_UP) { + if (t->dev->type == dev_type) + return t; + if (t->dev->type == ARPHRD_IPGRE && !t2) + t2 = t; + } } } + for (t = ign->tunnels_wc[h1]; t; t = t->next) { - if (t->parms.i_key == key && (t->dev->flags&IFF_UP)) - return t; + if (t->parms.i_key == key && t->dev->flags & IFF_UP) { + if (t->dev->type == dev_type) + return t; + if (t->dev->type == ARPHRD_IPGRE && !t2) + t2 = t; + } } + if (t2) + return t2; + if (ign->fb_tunnel_dev->flags&IFF_UP) return netdev_priv(ign->fb_tunnel_dev); return NULL; @@ -252,25 +279,37 @@ static void ipgre_tunnel_unlink(struct ipgre_net *ign, struct ip_tunnel *t) } } -static struct ip_tunnel * ipgre_tunnel_locate(struct net *net, - struct ip_tunnel_parm *parms, int create) +static struct ip_tunnel *ipgre_tunnel_find(struct net *net, + struct ip_tunnel_parm *parms, + int type) { __be32 remote = parms->iph.daddr; __be32 local = parms->iph.saddr; __be32 key = parms->i_key; - struct ip_tunnel *t, **tp, *nt; + struct ip_tunnel *t, **tp; + struct ipgre_net *ign = net_generic(net, ipgre_net_id); + + for (tp = __ipgre_bucket(ign, parms); (t = *tp) != NULL; tp = &t->next) + if (local == t->parms.iph.saddr && + remote == t->parms.iph.daddr && + key == t->parms.i_key && + type == t->dev->type) + break; + + return t; +} + +static struct ip_tunnel * ipgre_tunnel_locate(struct net *net, + struct ip_tunnel_parm *parms, int create) +{ + struct ip_tunnel *t, *nt; struct net_device *dev; char name[IFNAMSIZ]; struct ipgre_net *ign = net_generic(net, ipgre_net_id); - for (tp = __ipgre_bucket(ign, parms); (t = *tp) != NULL; tp = &t->next) { - if (local == t->parms.iph.saddr && remote == t->parms.iph.daddr) { - if (key == t->parms.i_key) - return t; - } - } - if (!create) - return NULL; + t = ipgre_tunnel_find(net, parms, ARPHRD_IPGRE); + if (t || !create) + return t; if (parms->name[0]) strlcpy(name, parms->name, IFNAMSIZ); @@ -385,8 +424,9 @@ static void ipgre_err(struct sk_buff *skb, u32 info) read_lock(&ipgre_lock); t = ipgre_tunnel_lookup(dev_net(skb->dev), iph->daddr, iph->saddr, - (flags&GRE_KEY) ? - *(((__be32*)p) + (grehlen>>2) - 1) : 0); + flags & GRE_KEY ? + *(((__be32 *)p) + (grehlen / 4) - 1) : 0, + p[1]); if (t == NULL || t->parms.iph.daddr == 0 || ipv4_is_multicast(t->parms.iph.daddr)) goto out; @@ -436,6 +476,7 @@ static int ipgre_rcv(struct sk_buff *skb) u32 seqno = 0; struct ip_tunnel *tunnel; int offset = 4; + __be16 gre_proto; if (!pskb_may_pull(skb, 16)) goto drop_nolock; @@ -475,20 +516,22 @@ static int ipgre_rcv(struct sk_buff *skb) } } + gre_proto = *(__be16 *)(h + 2); + read_lock(&ipgre_lock); if ((tunnel = ipgre_tunnel_lookup(dev_net(skb->dev), - iph->saddr, iph->daddr, key)) != NULL) { + iph->saddr, iph->daddr, key, + gre_proto))) { struct net_device_stats *stats = &tunnel->dev->stats; secpath_reset(skb); - skb->protocol = *(__be16*)(h + 2); + skb->protocol = gre_proto; /* WCCP version 1 and 2 protocol decoding. * - Change protocol to IP * - When dealing with WCCPv2, Skip extra 4 bytes in GRE header */ - if (flags == 0 && - skb->protocol == htons(ETH_P_WCCP)) { + if (flags == 0 && gre_proto == htons(ETH_P_WCCP)) { skb->protocol = htons(ETH_P_IP); if ((*(h + offset) & 0xF0) != 0x40) offset += 4; @@ -496,7 +539,6 @@ static int ipgre_rcv(struct sk_buff *skb) skb->mac_header = skb->network_header; __pskb_pull(skb, offset); - skb_reset_network_header(skb); skb_postpull_rcsum(skb, skb_transport_header(skb), offset); skb->pkt_type = PACKET_HOST; #ifdef CONFIG_NET_IPGRE_BROADCAST @@ -524,13 +566,30 @@ static int ipgre_rcv(struct sk_buff *skb) } 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)) { + stats->rx_length_errors++; + stats->rx_errors++; + goto drop; + } + + iph = ip_hdr(skb); + skb->protocol = eth_type_trans(skb, tunnel->dev); + skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN); + } + stats->rx_packets++; stats->rx_bytes += skb->len; skb->dev = tunnel->dev; dst_release(skb->dst); skb->dst = NULL; nf_reset(skb); + + skb_reset_network_header(skb); ipgre_ecn_decapsulate(iph, skb); + netif_rx(skb); read_unlock(&ipgre_lock); return(0); @@ -565,7 +624,10 @@ static int ipgre_tunnel_xmit(struct sk_buff *skb, struct net_device *dev) goto tx_error; } - if (dev->header_ops) { + if (dev->type == ARPHRD_ETHER) + IPCB(skb)->flags = 0; + + if (dev->header_ops && dev->type == ARPHRD_IPGRE) { gre_hlen = 0; tiph = (struct iphdr*)skb->data; } else { @@ -741,8 +803,9 @@ static int ipgre_tunnel_xmit(struct sk_buff *skb, struct net_device *dev) iph->ttl = dst_metric(&rt->u.dst, RTAX_HOPLIMIT); } - ((__be16*)(iph+1))[0] = tunnel->parms.o_flags; - ((__be16*)(iph+1))[1] = skb->protocol; + ((__be16 *)(iph + 1))[0] = tunnel->parms.o_flags; + ((__be16 *)(iph + 1))[1] = (dev->type == ARPHRD_ETHER) ? + htons(ETH_P_TEB) : skb->protocol; if (tunnel->parms.o_flags&(GRE_KEY|GRE_CSUM|GRE_SEQ)) { __be32 *ptr = (__be32*)(((u8*)iph) + tunnel->hlen - 4); @@ -804,7 +867,9 @@ static int ipgre_tunnel_bind_dev(struct net_device *dev) tdev = rt->u.dst.dev; ip_rt_put(rt); } - dev->flags |= IFF_POINTOPOINT; + + if (dev->type != ARPHRD_ETHER) + dev->flags |= IFF_POINTOPOINT; } if (!tdev && tunnel->parms.link) @@ -1250,6 +1315,30 @@ static int ipgre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[]) return 0; } +static int ipgre_tap_validate(struct nlattr *tb[], struct nlattr *data[]) +{ + __be32 daddr; + + if (tb[IFLA_ADDRESS]) { + if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) + return -EINVAL; + if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) + return -EADDRNOTAVAIL; + } + + if (!data) + goto out; + + if (data[IFLA_GRE_REMOTE]) { + memcpy(&daddr, nla_data(data[IFLA_GRE_REMOTE]), 4); + if (!daddr) + return -EINVAL; + } + +out: + return ipgre_tunnel_validate(tb, data); +} + static void ipgre_netlink_parms(struct nlattr *data[], struct ip_tunnel_parm *parms) { @@ -1291,6 +1380,35 @@ static void ipgre_netlink_parms(struct nlattr *data[], parms->iph.frag_off = htons(IP_DF); } +static int ipgre_tap_init(struct net_device *dev) +{ + struct ip_tunnel *tunnel; + + tunnel = netdev_priv(dev); + + tunnel->dev = dev; + strcpy(tunnel->parms.name, dev->name); + + ipgre_tunnel_bind_dev(dev); + + return 0; +} + +static void ipgre_tap_setup(struct net_device *dev) +{ + + ether_setup(dev); + + dev->init = ipgre_tap_init; + dev->uninit = ipgre_tunnel_uninit; + dev->destructor = free_netdev; + dev->hard_start_xmit = ipgre_tunnel_xmit; + dev->change_mtu = ipgre_tunnel_change_mtu; + + dev->iflink = 0; + dev->features |= NETIF_F_NETNS_LOCAL; +} + static int ipgre_newlink(struct net_device *dev, struct nlattr *tb[], struct nlattr *data[]) { @@ -1303,9 +1421,12 @@ static int ipgre_newlink(struct net_device *dev, struct nlattr *tb[], nt = netdev_priv(dev); ipgre_netlink_parms(data, &nt->parms); - if (ipgre_tunnel_locate(net, &nt->parms, 0)) + if (ipgre_tunnel_find(net, &nt->parms, dev->type)) return -EEXIST; + if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS]) + random_ether_addr(dev->dev_addr); + mtu = ipgre_tunnel_bind_dev(dev); if (!tb[IFLA_MTU]) dev->mtu = mtu; @@ -1455,6 +1576,19 @@ static struct rtnl_link_ops ipgre_link_ops __read_mostly = { .fill_info = ipgre_fill_info, }; +static struct rtnl_link_ops ipgre_tap_ops __read_mostly = { + .kind = "gretap", + .maxtype = IFLA_GRE_MAX, + .policy = ipgre_policy, + .priv_size = sizeof(struct ip_tunnel), + .setup = ipgre_tap_setup, + .validate = ipgre_tap_validate, + .newlink = ipgre_newlink, + .changelink = ipgre_changelink, + .get_size = ipgre_get_size, + .fill_info = ipgre_fill_info, +}; + /* * And now the modules code and kernel interface. */ @@ -1478,9 +1612,15 @@ static int __init ipgre_init(void) if (err < 0) goto rtnl_link_failed; + err = rtnl_link_register(&ipgre_tap_ops); + if (err < 0) + goto tap_ops_failed; + out: return err; +tap_ops_failed: + rtnl_link_unregister(&ipgre_link_ops); rtnl_link_failed: unregister_pernet_gen_device(ipgre_net_id, &ipgre_net_ops); gen_device_failed: @@ -1490,6 +1630,7 @@ gen_device_failed: static void __exit ipgre_fini(void) { + rtnl_link_unregister(&ipgre_tap_ops); rtnl_link_unregister(&ipgre_link_ops); unregister_pernet_gen_device(ipgre_net_id, &ipgre_net_ops); if (inet_del_protocol(&ipgre_protocol, IPPROTO_GRE) < 0) @@ -1500,3 +1641,4 @@ module_init(ipgre_init); module_exit(ipgre_fini); MODULE_LICENSE("GPL"); MODULE_ALIAS("rtnl-link-gre"); +MODULE_ALIAS("rtnl-link-gretap"); -- cgit v1.2.3-58-ga151