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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /net/mpls/mpls_iptunnel.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'net/mpls/mpls_iptunnel.c')
-rw-r--r--net/mpls/mpls_iptunnel.c305
1 files changed, 305 insertions, 0 deletions
diff --git a/net/mpls/mpls_iptunnel.c b/net/mpls/mpls_iptunnel.c
new file mode 100644
index 000000000..ef59e25dc
--- /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, <roopa@cumulusnetworks.com>
+ */
+#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] = { .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");