diff options
Diffstat (limited to 'net')
| -rw-r--r-- | net/mpls/Kconfig | 8 | ||||
| -rw-r--r-- | net/mpls/Makefile | 1 | ||||
| -rw-r--r-- | net/mpls/mpls_iptunnel.c | 233 |
3 files changed, 241 insertions, 1 deletions
diff --git a/net/mpls/Kconfig b/net/mpls/Kconfig index 17bde79..5c467ef 100644 --- a/net/mpls/Kconfig +++ b/net/mpls/Kconfig @@ -24,7 +24,13 @@ config NET_MPLS_GSO config MPLS_ROUTING tristate "MPLS: routing support" - help + ---help--- Add support for forwarding of mpls packets. +config MPLS_IPTUNNEL + tristate "MPLS: IP over MPLS tunnel support" + depends on LWTUNNEL && MPLS_ROUTING + ---help--- + mpls ip tunnel support. + endif # MPLS diff --git a/net/mpls/Makefile b/net/mpls/Makefile index 65bbe68..9ca9236 100644 --- a/net/mpls/Makefile +++ b/net/mpls/Makefile @@ -3,5 +3,6 @@ # obj-$(CONFIG_NET_MPLS_GSO) += mpls_gso.o obj-$(CONFIG_MPLS_ROUTING) += mpls_router.o +obj-$(CONFIG_MPLS_IPTUNNEL) += mpls_iptunnel.o mpls_router-y := af_mpls.o diff --git a/net/mpls/mpls_iptunnel.c b/net/mpls/mpls_iptunnel.c new file mode 100644 index 0000000..eea096f --- /dev/null +++ b/net/mpls/mpls_iptunnel.c @@ -0,0 +1,233 @@ +/* + * mpls tunnels An implementation mpls tunnels using the light weight tunnel + * infrastructure + * + * Authors: Roopa Prabhu, <roopa@cumulusnetworks.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/types.h> +#include <linux/skbuff.h> +#include <linux/net.h> +#include <linux/module.h> +#include <linux/mpls.h> +#include <linux/vmalloc.h> +#include <net/ip.h> +#include <net/dst.h> +#include <net/lwtunnel.h> +#include <net/netevent.h> +#include <net/netns/generic.h> +#include <net/ip6_fib.h> +#include <net/route.h> +#include <net/mpls_iptunnel.h> +#include <linux/mpls_iptunnel.h> +#include "internal.h" + +static const struct nla_policy mpls_iptunnel_policy[MPLS_IPTUNNEL_MAX + 1] = { + [MPLS_IPTUNNEL_DST] = { .type = NLA_U32 }, +}; + +static unsigned int mpls_encap_size(struct mpls_iptunnel_encap *en) +{ + /* The size of the layer 2.5 labels to be added for this route */ + return en->labels * sizeof(struct mpls_shim_hdr); +} + +int mpls_output(struct sock *sk, struct sk_buff *skb) +{ + struct mpls_iptunnel_encap *tun_encap_info; + struct mpls_shim_hdr *hdr; + struct net_device *out_dev; + unsigned int hh_len; + unsigned int new_header_size; + unsigned int mtu; + struct dst_entry *dst = skb_dst(skb); + struct rtable *rt = NULL; + struct rt6_info *rt6 = NULL; + struct lwtunnel_state *lwtstate = NULL; + int err = 0; + bool bos; + int i; + unsigned int ttl; + + /* Obtain the ttl */ + if (skb->protocol == htons(ETH_P_IP)) { + ttl = ip_hdr(skb)->ttl; + rt = (struct rtable *)dst; + lwtstate = rt->rt_lwtstate; + } else if (skb->protocol == htons(ETH_P_IPV6)) { + ttl = ipv6_hdr(skb)->hop_limit; + rt6 = (struct rt6_info *)dst; + lwtstate = rt6->rt6i_lwtstate; + } else { + goto drop; + } + + skb_orphan(skb); + + /* Find the output device */ + out_dev = rcu_dereference(dst->dev); + if (!mpls_output_possible(out_dev) || + !lwtstate || skb_warn_if_lro(skb)) + goto drop; + + skb_forward_csum(skb); + + tun_encap_info = mpls_lwtunnel_encap(lwtstate); + + /* Verify the destination can hold the packet */ + new_header_size = mpls_encap_size(tun_encap_info); + mtu = mpls_dev_mtu(out_dev); + if (mpls_pkt_too_big(skb, mtu - new_header_size)) + goto drop; + + hh_len = LL_RESERVED_SPACE(out_dev); + if (!out_dev->header_ops) + hh_len = 0; + + /* Ensure there is enough space for the headers in the skb */ + if (skb_cow(skb, hh_len + new_header_size)) + goto drop; + + skb_push(skb, new_header_size); + skb_reset_network_header(skb); + + skb->dev = out_dev; + skb->protocol = htons(ETH_P_MPLS_UC); + + /* Push the new labels */ + hdr = mpls_hdr(skb); + bos = true; + for (i = tun_encap_info->labels - 1; i >= 0; i--) { + hdr[i] = mpls_entry_encode(tun_encap_info->label[i], + ttl, 0, bos); + bos = false; + } + + if (rt) + err = neigh_xmit(NEIGH_ARP_TABLE, out_dev, &rt->rt_gateway, + skb); + else if (rt6) + err = neigh_xmit(NEIGH_ND_TABLE, out_dev, &rt6->rt6i_gateway, + skb); + if (err) + net_dbg_ratelimited("%s: packet transmission failed: %d\n", + __func__, err); + + return 0; + +drop: + kfree_skb(skb); + return -EINVAL; +} + +static int mpls_build_state(struct net_device *dev, struct nlattr *nla, + struct lwtunnel_state **ts) +{ + struct mpls_iptunnel_encap *tun_encap_info; + struct nlattr *tb[MPLS_IPTUNNEL_MAX + 1]; + struct lwtunnel_state *newts; + int tun_encap_info_len; + int ret; + + ret = nla_parse_nested(tb, MPLS_IPTUNNEL_MAX, nla, + mpls_iptunnel_policy); + if (ret < 0) + return ret; + + if (!tb[MPLS_IPTUNNEL_DST]) + return -EINVAL; + + tun_encap_info_len = sizeof(*tun_encap_info); + + newts = lwtunnel_state_alloc(tun_encap_info_len); + if (!newts) + return -ENOMEM; + + newts->len = tun_encap_info_len; + tun_encap_info = mpls_lwtunnel_encap(newts); + ret = nla_get_labels(tb[MPLS_IPTUNNEL_DST], MAX_NEW_LABELS, + &tun_encap_info->labels, tun_encap_info->label); + if (ret) + goto errout; + newts->type = LWTUNNEL_ENCAP_MPLS; + newts->flags |= LWTUNNEL_STATE_OUTPUT_REDIRECT; + + *ts = newts; + + return 0; + +errout: + kfree(newts); + *ts = NULL; + + return ret; +} + +static int mpls_fill_encap_info(struct sk_buff *skb, + struct lwtunnel_state *lwtstate) +{ + struct mpls_iptunnel_encap *tun_encap_info; + + tun_encap_info = mpls_lwtunnel_encap(lwtstate); + + if (nla_put_labels(skb, MPLS_IPTUNNEL_DST, tun_encap_info->labels, + tun_encap_info->label)) + goto nla_put_failure; + + return 0; + +nla_put_failure: + return -EMSGSIZE; +} + +static int mpls_encap_nlsize(struct lwtunnel_state *lwtstate) +{ + struct mpls_iptunnel_encap *tun_encap_info; + + tun_encap_info = mpls_lwtunnel_encap(lwtstate); + + return nla_total_size(tun_encap_info->labels * 4); +} + +static int mpls_encap_cmp(struct lwtunnel_state *a, struct lwtunnel_state *b) +{ + struct mpls_iptunnel_encap *a_hdr = mpls_lwtunnel_encap(a); + struct mpls_iptunnel_encap *b_hdr = mpls_lwtunnel_encap(b); + int l; + + if (a_hdr->labels != b_hdr->labels) + return 1; + + for (l = 0; l < MAX_NEW_LABELS; l++) + if (a_hdr->label[l] != b_hdr->label[l]) + return 1; + return 0; +} + +static const struct lwtunnel_encap_ops mpls_iptun_ops = { + .build_state = mpls_build_state, + .output = mpls_output, + .fill_encap = mpls_fill_encap_info, + .get_encap_size = mpls_encap_nlsize, + .cmp_encap = mpls_encap_cmp, +}; + +static int __init mpls_iptunnel_init(void) +{ + return lwtunnel_encap_add_ops(&mpls_iptun_ops, LWTUNNEL_ENCAP_MPLS); +} +module_init(mpls_iptunnel_init); + +static void __exit mpls_iptunnel_exit(void) +{ + lwtunnel_encap_del_ops(&mpls_iptun_ops, LWTUNNEL_ENCAP_MPLS); +} +module_exit(mpls_iptunnel_exit); + +MODULE_DESCRIPTION("MultiProtocol Label Switching IP Tunnels"); +MODULE_LICENSE("GPL v2"); |
