From ace9429bb58fd418f0c81d4c2835699bddf6bde6 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Thu, 11 Apr 2024 10:27:49 +0200 Subject: Adding upstream version 6.6.15. Signed-off-by: Daniel Baumann --- net/mpls/mpls_iptunnel.c | 305 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 305 insertions(+) create mode 100644 net/mpls/mpls_iptunnel.c (limited to 'net/mpls/mpls_iptunnel.c') diff --git a/net/mpls/mpls_iptunnel.c b/net/mpls/mpls_iptunnel.c new file mode 100644 index 0000000000..ef59e25dc4 --- /dev/null +++ b/net/mpls/mpls_iptunnel.c @@ -0,0 +1,305 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * mpls tunnels An implementation mpls tunnels using the light weight tunnel + * infrastructure + * + * Authors: Roopa Prabhu, + */ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "internal.h" + +static const struct nla_policy mpls_iptunnel_policy[MPLS_IPTUNNEL_MAX + 1] = { + [MPLS_IPTUNNEL_DST] = { .len = sizeof(u32) }, + [MPLS_IPTUNNEL_TTL] = { .type = NLA_U8 }, +}; + +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); +} + +static int mpls_xmit(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 mpls_dev *out_mdev; + struct net *net; + int err = 0; + bool bos; + int i; + unsigned int ttl; + + /* Find the output device */ + out_dev = dst->dev; + net = dev_net(out_dev); + + skb_orphan(skb); + + if (!mpls_output_possible(out_dev) || + !dst->lwtstate || skb_warn_if_lro(skb)) + goto drop; + + skb_forward_csum(skb); + + tun_encap_info = mpls_lwtunnel_encap(dst->lwtstate); + + /* Obtain the ttl using the following set of rules. + * + * LWT ttl propagation setting: + * - disabled => use default TTL value from LWT + * - enabled => use TTL value from IPv4/IPv6 header + * - default => + * Global ttl propagation setting: + * - disabled => use default TTL value from global setting + * - enabled => use TTL value from IPv4/IPv6 header + */ + if (dst->ops->family == AF_INET) { + if (tun_encap_info->ttl_propagate == MPLS_TTL_PROP_DISABLED) + ttl = tun_encap_info->default_ttl; + else if (tun_encap_info->ttl_propagate == MPLS_TTL_PROP_DEFAULT && + !net->mpls.ip_ttl_propagate) + ttl = net->mpls.default_ttl; + else + ttl = ip_hdr(skb)->ttl; + rt = (struct rtable *)dst; + } else if (dst->ops->family == AF_INET6) { + if (tun_encap_info->ttl_propagate == MPLS_TTL_PROP_DISABLED) + ttl = tun_encap_info->default_ttl; + else if (tun_encap_info->ttl_propagate == MPLS_TTL_PROP_DEFAULT && + !net->mpls.ip_ttl_propagate) + ttl = net->mpls.default_ttl; + else + ttl = ipv6_hdr(skb)->hop_limit; + rt6 = (struct rt6_info *)dst; + } else { + goto drop; + } + + /* 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_set_inner_protocol(skb, skb->protocol); + skb_reset_inner_network_header(skb); + + 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; + } + + mpls_stats_inc_outucastpkts(out_dev, skb); + + if (rt) { + if (rt->rt_gw_family == AF_INET6) + err = neigh_xmit(NEIGH_ND_TABLE, out_dev, &rt->rt_gw6, + skb); + else + err = neigh_xmit(NEIGH_ARP_TABLE, out_dev, &rt->rt_gw4, + skb); + } else if (rt6) { + if (ipv6_addr_v4mapped(&rt6->rt6i_gateway)) { + /* 6PE (RFC 4798) */ + err = neigh_xmit(NEIGH_ARP_TABLE, out_dev, &rt6->rt6i_gateway.s6_addr32[3], + skb); + } else + 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 LWTUNNEL_XMIT_DONE; + +drop: + out_mdev = out_dev ? mpls_dev_get(out_dev) : NULL; + if (out_mdev) + MPLS_INC_STATS(out_mdev, tx_errors); + kfree_skb(skb); + return -EINVAL; +} + +static int mpls_build_state(struct net *net, struct nlattr *nla, + unsigned int family, const void *cfg, + struct lwtunnel_state **ts, + struct netlink_ext_ack *extack) +{ + struct mpls_iptunnel_encap *tun_encap_info; + struct nlattr *tb[MPLS_IPTUNNEL_MAX + 1]; + struct lwtunnel_state *newts; + u8 n_labels; + int ret; + + ret = nla_parse_nested_deprecated(tb, MPLS_IPTUNNEL_MAX, nla, + mpls_iptunnel_policy, extack); + if (ret < 0) + return ret; + + if (!tb[MPLS_IPTUNNEL_DST]) { + NL_SET_ERR_MSG(extack, "MPLS_IPTUNNEL_DST attribute is missing"); + return -EINVAL; + } + + /* determine number of labels */ + if (nla_get_labels(tb[MPLS_IPTUNNEL_DST], MAX_NEW_LABELS, + &n_labels, NULL, extack)) + return -EINVAL; + + newts = lwtunnel_state_alloc(struct_size(tun_encap_info, label, + n_labels)); + if (!newts) + return -ENOMEM; + + tun_encap_info = mpls_lwtunnel_encap(newts); + ret = nla_get_labels(tb[MPLS_IPTUNNEL_DST], n_labels, + &tun_encap_info->labels, tun_encap_info->label, + extack); + if (ret) + goto errout; + + tun_encap_info->ttl_propagate = MPLS_TTL_PROP_DEFAULT; + + if (tb[MPLS_IPTUNNEL_TTL]) { + tun_encap_info->default_ttl = nla_get_u8(tb[MPLS_IPTUNNEL_TTL]); + /* TTL 0 implies propagate from IP header */ + tun_encap_info->ttl_propagate = tun_encap_info->default_ttl ? + MPLS_TTL_PROP_DISABLED : + MPLS_TTL_PROP_ENABLED; + } + + newts->type = LWTUNNEL_ENCAP_MPLS; + newts->flags |= LWTUNNEL_STATE_XMIT_REDIRECT; + newts->headroom = mpls_encap_size(tun_encap_info); + + *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; + + if (tun_encap_info->ttl_propagate != MPLS_TTL_PROP_DEFAULT && + nla_put_u8(skb, MPLS_IPTUNNEL_TTL, tun_encap_info->default_ttl)) + 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; + int nlsize; + + tun_encap_info = mpls_lwtunnel_encap(lwtstate); + + nlsize = nla_total_size(tun_encap_info->labels * 4); + + if (tun_encap_info->ttl_propagate != MPLS_TTL_PROP_DEFAULT) + nlsize += nla_total_size(1); + + return nlsize; +} + +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 || + a_hdr->ttl_propagate != b_hdr->ttl_propagate || + a_hdr->default_ttl != b_hdr->default_ttl) + return 1; + + for (l = 0; l < a_hdr->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, + .xmit = mpls_xmit, + .fill_encap = mpls_fill_encap_info, + .get_encap_size = mpls_encap_nlsize, + .cmp_encap = mpls_encap_cmp, + .owner = THIS_MODULE, +}; + +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_ALIAS_RTNL_LWT(MPLS); +MODULE_SOFTDEP("post: mpls_gso"); +MODULE_DESCRIPTION("MultiProtocol Label Switching IP Tunnels"); +MODULE_LICENSE("GPL v2"); -- cgit v1.2.3