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authorLinus Torvalds <torvalds@linux-foundation.org>2015-04-15 09:00:47 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2015-04-15 09:00:47 -0700
commit6c373ca89399c5a3f7ef210ad8f63dc3437da345 (patch)
tree74d1ec65087df1da1021b43ac51acc1ee8601809 /net/mpls
parentMerge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm (diff)
parentMerge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/jkirsher/next-queue (diff)
downloadlinux-dev-6c373ca89399c5a3f7ef210ad8f63dc3437da345.tar.xz
linux-dev-6c373ca89399c5a3f7ef210ad8f63dc3437da345.zip
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller: 1) Add BQL support to via-rhine, from Tino Reichardt. 2) Integrate SWITCHDEV layer support into the DSA layer, so DSA drivers can support hw switch offloading. From Floria Fainelli. 3) Allow 'ip address' commands to initiate multicast group join/leave, from Madhu Challa. 4) Many ipv4 FIB lookup optimizations from Alexander Duyck. 5) Support EBPF in cls_bpf classifier and act_bpf action, from Daniel Borkmann. 6) Remove the ugly compat support in ARP for ugly layers like ax25, rose, etc. And use this to clean up the neigh layer, then use it to implement MPLS support. All from Eric Biederman. 7) Support L3 forwarding offloading in switches, from Scott Feldman. 8) Collapse the LOCAL and MAIN ipv4 FIB tables when possible, to speed up route lookups even further. From Alexander Duyck. 9) Many improvements and bug fixes to the rhashtable implementation, from Herbert Xu and Thomas Graf. In particular, in the case where an rhashtable user bulk adds a large number of items into an empty table, we expand the table much more sanely. 10) Don't make the tcp_metrics hash table per-namespace, from Eric Biederman. 11) Extend EBPF to access SKB fields, from Alexei Starovoitov. 12) Split out new connection request sockets so that they can be established in the main hash table. Much less false sharing since hash lookups go direct to the request sockets instead of having to go first to the listener then to the request socks hashed underneath. From Eric Dumazet. 13) Add async I/O support for crytpo AF_ALG sockets, from Tadeusz Struk. 14) Support stable privacy address generation for RFC7217 in IPV6. From Hannes Frederic Sowa. 15) Hash network namespace into IP frag IDs, also from Hannes Frederic Sowa. 16) Convert PTP get/set methods to use 64-bit time, from Richard Cochran. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1816 commits) fm10k: Bump driver version to 0.15.2 fm10k: corrected VF multicast update fm10k: mbx_update_max_size does not drop all oversized messages fm10k: reset head instead of calling update_max_size fm10k: renamed mbx_tx_dropped to mbx_tx_oversized fm10k: update xcast mode before synchronizing multicast addresses fm10k: start service timer on probe fm10k: fix function header comment fm10k: comment next_vf_mbx flow fm10k: don't handle mailbox events in iov_event path and always process mailbox fm10k: use separate workqueue for fm10k driver fm10k: Set PF queues to unlimited bandwidth during virtualization fm10k: expose tx_timeout_count as an ethtool stat fm10k: only increment tx_timeout_count in Tx hang path fm10k: remove extraneous "Reset interface" message fm10k: separate PF only stats so that VF does not display them fm10k: use hw->mac.max_queues for stats fm10k: only show actual queues, not the maximum in hardware fm10k: allow creation of VLAN on default vid fm10k: fix unused warnings ...
Diffstat (limited to 'net/mpls')
-rw-r--r--net/mpls/Kconfig21
-rw-r--r--net/mpls/Makefile3
-rw-r--r--net/mpls/af_mpls.c1023
-rw-r--r--net/mpls/internal.h59
4 files changed, 1106 insertions, 0 deletions
diff --git a/net/mpls/Kconfig b/net/mpls/Kconfig
index 37421db88965..17bde799c854 100644
--- a/net/mpls/Kconfig
+++ b/net/mpls/Kconfig
@@ -1,9 +1,30 @@
#
# MPLS configuration
#
+
+menuconfig MPLS
+ bool "MultiProtocol Label Switching"
+ default n
+ ---help---
+ MultiProtocol Label Switching routes packets through logical
+ circuits. Originally conceived as a way of routing packets at
+ hardware speeds (before hardware was capable of routing ipv4 packets),
+ MPLS remains a simple way of making tunnels.
+
+ If you have not heard of MPLS you probably want to say N here.
+
+if MPLS
+
config NET_MPLS_GSO
tristate "MPLS: GSO support"
help
This is helper module to allow segmentation of non-MPLS GSO packets
that have had MPLS stack entries pushed onto them and thus
become MPLS GSO packets.
+
+config MPLS_ROUTING
+ tristate "MPLS: routing support"
+ help
+ Add support for forwarding of mpls packets.
+
+endif # MPLS
diff --git a/net/mpls/Makefile b/net/mpls/Makefile
index 6dec088c2d0f..65bbe68c72e6 100644
--- a/net/mpls/Makefile
+++ b/net/mpls/Makefile
@@ -2,3 +2,6 @@
# Makefile for MPLS.
#
obj-$(CONFIG_NET_MPLS_GSO) += mpls_gso.o
+obj-$(CONFIG_MPLS_ROUTING) += mpls_router.o
+
+mpls_router-y := af_mpls.o
diff --git a/net/mpls/af_mpls.c b/net/mpls/af_mpls.c
new file mode 100644
index 000000000000..db8a2ea6d4de
--- /dev/null
+++ b/net/mpls/af_mpls.c
@@ -0,0 +1,1023 @@
+#include <linux/types.h>
+#include <linux/skbuff.h>
+#include <linux/socket.h>
+#include <linux/sysctl.h>
+#include <linux/net.h>
+#include <linux/module.h>
+#include <linux/if_arp.h>
+#include <linux/ipv6.h>
+#include <linux/mpls.h>
+#include <linux/vmalloc.h>
+#include <net/ip.h>
+#include <net/dst.h>
+#include <net/sock.h>
+#include <net/arp.h>
+#include <net/ip_fib.h>
+#include <net/netevent.h>
+#include <net/netns/generic.h>
+#include "internal.h"
+
+#define LABEL_NOT_SPECIFIED (1<<20)
+#define MAX_NEW_LABELS 2
+
+/* This maximum ha length copied from the definition of struct neighbour */
+#define MAX_VIA_ALEN (ALIGN(MAX_ADDR_LEN, sizeof(unsigned long)))
+
+struct mpls_route { /* next hop label forwarding entry */
+ struct net_device __rcu *rt_dev;
+ struct rcu_head rt_rcu;
+ u32 rt_label[MAX_NEW_LABELS];
+ u8 rt_protocol; /* routing protocol that set this entry */
+ u8 rt_labels;
+ u8 rt_via_alen;
+ u8 rt_via_table;
+ u8 rt_via[0];
+};
+
+static int zero = 0;
+static int label_limit = (1 << 20) - 1;
+
+static void rtmsg_lfib(int event, u32 label, struct mpls_route *rt,
+ struct nlmsghdr *nlh, struct net *net, u32 portid,
+ unsigned int nlm_flags);
+
+static struct mpls_route *mpls_route_input_rcu(struct net *net, unsigned index)
+{
+ struct mpls_route *rt = NULL;
+
+ if (index < net->mpls.platform_labels) {
+ struct mpls_route __rcu **platform_label =
+ rcu_dereference(net->mpls.platform_label);
+ rt = rcu_dereference(platform_label[index]);
+ }
+ return rt;
+}
+
+static bool mpls_output_possible(const struct net_device *dev)
+{
+ return dev && (dev->flags & IFF_UP) && netif_carrier_ok(dev);
+}
+
+static unsigned int mpls_rt_header_size(const struct mpls_route *rt)
+{
+ /* The size of the layer 2.5 labels to be added for this route */
+ return rt->rt_labels * sizeof(struct mpls_shim_hdr);
+}
+
+static unsigned int mpls_dev_mtu(const struct net_device *dev)
+{
+ /* The amount of data the layer 2 frame can hold */
+ return dev->mtu;
+}
+
+static bool mpls_pkt_too_big(const struct sk_buff *skb, unsigned int mtu)
+{
+ if (skb->len <= mtu)
+ return false;
+
+ if (skb_is_gso(skb) && skb_gso_network_seglen(skb) <= mtu)
+ return false;
+
+ return true;
+}
+
+static bool mpls_egress(struct mpls_route *rt, struct sk_buff *skb,
+ struct mpls_entry_decoded dec)
+{
+ /* RFC4385 and RFC5586 encode other packets in mpls such that
+ * they don't conflict with the ip version number, making
+ * decoding by examining the ip version correct in everything
+ * except for the strangest cases.
+ *
+ * The strange cases if we choose to support them will require
+ * manual configuration.
+ */
+ struct iphdr *hdr4;
+ bool success = true;
+
+ /* The IPv4 code below accesses through the IPv4 header
+ * checksum, which is 12 bytes into the packet.
+ * The IPv6 code below accesses through the IPv6 hop limit
+ * which is 8 bytes into the packet.
+ *
+ * For all supported cases there should always be at least 12
+ * bytes of packet data present. The IPv4 header is 20 bytes
+ * without options and the IPv6 header is always 40 bytes
+ * long.
+ */
+ if (!pskb_may_pull(skb, 12))
+ return false;
+
+ /* Use ip_hdr to find the ip protocol version */
+ hdr4 = ip_hdr(skb);
+ if (hdr4->version == 4) {
+ skb->protocol = htons(ETH_P_IP);
+ csum_replace2(&hdr4->check,
+ htons(hdr4->ttl << 8),
+ htons(dec.ttl << 8));
+ hdr4->ttl = dec.ttl;
+ }
+ else if (hdr4->version == 6) {
+ struct ipv6hdr *hdr6 = ipv6_hdr(skb);
+ skb->protocol = htons(ETH_P_IPV6);
+ hdr6->hop_limit = dec.ttl;
+ }
+ else
+ /* version 0 and version 1 are used by pseudo wires */
+ success = false;
+ return success;
+}
+
+static int mpls_forward(struct sk_buff *skb, struct net_device *dev,
+ struct packet_type *pt, struct net_device *orig_dev)
+{
+ struct net *net = dev_net(dev);
+ struct mpls_shim_hdr *hdr;
+ struct mpls_route *rt;
+ struct mpls_entry_decoded dec;
+ struct net_device *out_dev;
+ unsigned int hh_len;
+ unsigned int new_header_size;
+ unsigned int mtu;
+ int err;
+
+ /* Careful this entire function runs inside of an rcu critical section */
+
+ if (skb->pkt_type != PACKET_HOST)
+ goto drop;
+
+ if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
+ goto drop;
+
+ if (!pskb_may_pull(skb, sizeof(*hdr)))
+ goto drop;
+
+ /* Read and decode the label */
+ hdr = mpls_hdr(skb);
+ dec = mpls_entry_decode(hdr);
+
+ /* Pop the label */
+ skb_pull(skb, sizeof(*hdr));
+ skb_reset_network_header(skb);
+
+ skb_orphan(skb);
+
+ rt = mpls_route_input_rcu(net, dec.label);
+ if (!rt)
+ goto drop;
+
+ /* Find the output device */
+ out_dev = rcu_dereference(rt->rt_dev);
+ if (!mpls_output_possible(out_dev))
+ goto drop;
+
+ if (skb_warn_if_lro(skb))
+ goto drop;
+
+ skb_forward_csum(skb);
+
+ /* Verify ttl is valid */
+ if (dec.ttl <= 1)
+ goto drop;
+ dec.ttl -= 1;
+
+ /* Verify the destination can hold the packet */
+ new_header_size = mpls_rt_header_size(rt);
+ 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->dev = out_dev;
+ skb->protocol = htons(ETH_P_MPLS_UC);
+
+ if (unlikely(!new_header_size && dec.bos)) {
+ /* Penultimate hop popping */
+ if (!mpls_egress(rt, skb, dec))
+ goto drop;
+ } else {
+ bool bos;
+ int i;
+ skb_push(skb, new_header_size);
+ skb_reset_network_header(skb);
+ /* Push the new labels */
+ hdr = mpls_hdr(skb);
+ bos = dec.bos;
+ for (i = rt->rt_labels - 1; i >= 0; i--) {
+ hdr[i] = mpls_entry_encode(rt->rt_label[i], dec.ttl, 0, bos);
+ bos = false;
+ }
+ }
+
+ err = neigh_xmit(rt->rt_via_table, out_dev, rt->rt_via, skb);
+ if (err)
+ net_dbg_ratelimited("%s: packet transmission failed: %d\n",
+ __func__, err);
+ return 0;
+
+drop:
+ kfree_skb(skb);
+ return NET_RX_DROP;
+}
+
+static struct packet_type mpls_packet_type __read_mostly = {
+ .type = cpu_to_be16(ETH_P_MPLS_UC),
+ .func = mpls_forward,
+};
+
+static const struct nla_policy rtm_mpls_policy[RTA_MAX+1] = {
+ [RTA_DST] = { .type = NLA_U32 },
+ [RTA_OIF] = { .type = NLA_U32 },
+};
+
+struct mpls_route_config {
+ u32 rc_protocol;
+ u32 rc_ifindex;
+ u16 rc_via_table;
+ u16 rc_via_alen;
+ u8 rc_via[MAX_VIA_ALEN];
+ u32 rc_label;
+ u32 rc_output_labels;
+ u32 rc_output_label[MAX_NEW_LABELS];
+ u32 rc_nlflags;
+ struct nl_info rc_nlinfo;
+};
+
+static struct mpls_route *mpls_rt_alloc(size_t alen)
+{
+ struct mpls_route *rt;
+
+ rt = kzalloc(sizeof(*rt) + alen, GFP_KERNEL);
+ if (rt)
+ rt->rt_via_alen = alen;
+ return rt;
+}
+
+static void mpls_rt_free(struct mpls_route *rt)
+{
+ if (rt)
+ kfree_rcu(rt, rt_rcu);
+}
+
+static void mpls_notify_route(struct net *net, unsigned index,
+ struct mpls_route *old, struct mpls_route *new,
+ const struct nl_info *info)
+{
+ struct nlmsghdr *nlh = info ? info->nlh : NULL;
+ unsigned portid = info ? info->portid : 0;
+ int event = new ? RTM_NEWROUTE : RTM_DELROUTE;
+ struct mpls_route *rt = new ? new : old;
+ unsigned nlm_flags = (old && new) ? NLM_F_REPLACE : 0;
+ /* Ignore reserved labels for now */
+ if (rt && (index >= 16))
+ rtmsg_lfib(event, index, rt, nlh, net, portid, nlm_flags);
+}
+
+static void mpls_route_update(struct net *net, unsigned index,
+ struct net_device *dev, struct mpls_route *new,
+ const struct nl_info *info)
+{
+ struct mpls_route __rcu **platform_label;
+ struct mpls_route *rt, *old = NULL;
+
+ ASSERT_RTNL();
+
+ platform_label = rtnl_dereference(net->mpls.platform_label);
+ rt = rtnl_dereference(platform_label[index]);
+ if (!dev || (rt && (rtnl_dereference(rt->rt_dev) == dev))) {
+ rcu_assign_pointer(platform_label[index], new);
+ old = rt;
+ }
+
+ mpls_notify_route(net, index, old, new, info);
+
+ /* If we removed a route free it now */
+ mpls_rt_free(old);
+}
+
+static unsigned find_free_label(struct net *net)
+{
+ struct mpls_route __rcu **platform_label;
+ size_t platform_labels;
+ unsigned index;
+
+ platform_label = rtnl_dereference(net->mpls.platform_label);
+ platform_labels = net->mpls.platform_labels;
+ for (index = 16; index < platform_labels; index++) {
+ if (!rtnl_dereference(platform_label[index]))
+ return index;
+ }
+ return LABEL_NOT_SPECIFIED;
+}
+
+static int mpls_route_add(struct mpls_route_config *cfg)
+{
+ struct mpls_route __rcu **platform_label;
+ struct net *net = cfg->rc_nlinfo.nl_net;
+ struct net_device *dev = NULL;
+ struct mpls_route *rt, *old;
+ unsigned index;
+ int i;
+ int err = -EINVAL;
+
+ index = cfg->rc_label;
+
+ /* If a label was not specified during insert pick one */
+ if ((index == LABEL_NOT_SPECIFIED) &&
+ (cfg->rc_nlflags & NLM_F_CREATE)) {
+ index = find_free_label(net);
+ }
+
+ /* The first 16 labels are reserved, and may not be set */
+ if (index < 16)
+ goto errout;
+
+ /* The full 20 bit range may not be supported. */
+ if (index >= net->mpls.platform_labels)
+ goto errout;
+
+ /* Ensure only a supported number of labels are present */
+ if (cfg->rc_output_labels > MAX_NEW_LABELS)
+ goto errout;
+
+ err = -ENODEV;
+ dev = dev_get_by_index(net, cfg->rc_ifindex);
+ if (!dev)
+ goto errout;
+
+ /* For now just support ethernet devices */
+ err = -EINVAL;
+ if ((dev->type != ARPHRD_ETHER) && (dev->type != ARPHRD_LOOPBACK))
+ goto errout;
+
+ err = -EINVAL;
+ if ((cfg->rc_via_table == NEIGH_LINK_TABLE) &&
+ (dev->addr_len != cfg->rc_via_alen))
+ goto errout;
+
+ /* Append makes no sense with mpls */
+ err = -EOPNOTSUPP;
+ if (cfg->rc_nlflags & NLM_F_APPEND)
+ goto errout;
+
+ err = -EEXIST;
+ platform_label = rtnl_dereference(net->mpls.platform_label);
+ old = rtnl_dereference(platform_label[index]);
+ if ((cfg->rc_nlflags & NLM_F_EXCL) && old)
+ goto errout;
+
+ err = -EEXIST;
+ if (!(cfg->rc_nlflags & NLM_F_REPLACE) && old)
+ goto errout;
+
+ err = -ENOENT;
+ if (!(cfg->rc_nlflags & NLM_F_CREATE) && !old)
+ goto errout;
+
+ err = -ENOMEM;
+ rt = mpls_rt_alloc(cfg->rc_via_alen);
+ if (!rt)
+ goto errout;
+
+ rt->rt_labels = cfg->rc_output_labels;
+ for (i = 0; i < rt->rt_labels; i++)
+ rt->rt_label[i] = cfg->rc_output_label[i];
+ rt->rt_protocol = cfg->rc_protocol;
+ RCU_INIT_POINTER(rt->rt_dev, dev);
+ rt->rt_via_table = cfg->rc_via_table;
+ memcpy(rt->rt_via, cfg->rc_via, cfg->rc_via_alen);
+
+ mpls_route_update(net, index, NULL, rt, &cfg->rc_nlinfo);
+
+ dev_put(dev);
+ return 0;
+
+errout:
+ if (dev)
+ dev_put(dev);
+ return err;
+}
+
+static int mpls_route_del(struct mpls_route_config *cfg)
+{
+ struct net *net = cfg->rc_nlinfo.nl_net;
+ unsigned index;
+ int err = -EINVAL;
+
+ index = cfg->rc_label;
+
+ /* The first 16 labels are reserved, and may not be removed */
+ if (index < 16)
+ goto errout;
+
+ /* The full 20 bit range may not be supported */
+ if (index >= net->mpls.platform_labels)
+ goto errout;
+
+ mpls_route_update(net, index, NULL, NULL, &cfg->rc_nlinfo);
+
+ err = 0;
+errout:
+ return err;
+}
+
+static void mpls_ifdown(struct net_device *dev)
+{
+ struct mpls_route __rcu **platform_label;
+ struct net *net = dev_net(dev);
+ unsigned index;
+
+ platform_label = rtnl_dereference(net->mpls.platform_label);
+ for (index = 0; index < net->mpls.platform_labels; index++) {
+ struct mpls_route *rt = rtnl_dereference(platform_label[index]);
+ if (!rt)
+ continue;
+ if (rtnl_dereference(rt->rt_dev) != dev)
+ continue;
+ rt->rt_dev = NULL;
+ }
+}
+
+static int mpls_dev_notify(struct notifier_block *this, unsigned long event,
+ void *ptr)
+{
+ struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+
+ switch(event) {
+ case NETDEV_UNREGISTER:
+ mpls_ifdown(dev);
+ break;
+ }
+ return NOTIFY_OK;
+}
+
+static struct notifier_block mpls_dev_notifier = {
+ .notifier_call = mpls_dev_notify,
+};
+
+static int nla_put_via(struct sk_buff *skb,
+ u8 table, const void *addr, int alen)
+{
+ static const int table_to_family[NEIGH_NR_TABLES + 1] = {
+ AF_INET, AF_INET6, AF_DECnet, AF_PACKET,
+ };
+ struct nlattr *nla;
+ struct rtvia *via;
+ int family = AF_UNSPEC;
+
+ nla = nla_reserve(skb, RTA_VIA, alen + 2);
+ if (!nla)
+ return -EMSGSIZE;
+
+ if (table <= NEIGH_NR_TABLES)
+ family = table_to_family[table];
+
+ via = nla_data(nla);
+ via->rtvia_family = family;
+ memcpy(via->rtvia_addr, addr, alen);
+ return 0;
+}
+
+int nla_put_labels(struct sk_buff *skb, int attrtype,
+ u8 labels, const u32 label[])
+{
+ struct nlattr *nla;
+ struct mpls_shim_hdr *nla_label;
+ bool bos;
+ int i;
+ nla = nla_reserve(skb, attrtype, labels*4);
+ if (!nla)
+ return -EMSGSIZE;
+
+ nla_label = nla_data(nla);
+ bos = true;
+ for (i = labels - 1; i >= 0; i--) {
+ nla_label[i] = mpls_entry_encode(label[i], 0, 0, bos);
+ bos = false;
+ }
+
+ return 0;
+}
+
+int nla_get_labels(const struct nlattr *nla,
+ u32 max_labels, u32 *labels, u32 label[])
+{
+ unsigned len = nla_len(nla);
+ unsigned nla_labels;
+ struct mpls_shim_hdr *nla_label;
+ bool bos;
+ int i;
+
+ /* len needs to be an even multiple of 4 (the label size) */
+ if (len & 3)
+ return -EINVAL;
+
+ /* Limit the number of new labels allowed */
+ nla_labels = len/4;
+ if (nla_labels > max_labels)
+ return -EINVAL;
+
+ nla_label = nla_data(nla);
+ bos = true;
+ for (i = nla_labels - 1; i >= 0; i--, bos = false) {
+ struct mpls_entry_decoded dec;
+ dec = mpls_entry_decode(nla_label + i);
+
+ /* Ensure the bottom of stack flag is properly set
+ * and ttl and tc are both clear.
+ */
+ if ((dec.bos != bos) || dec.ttl || dec.tc)
+ return -EINVAL;
+
+ label[i] = dec.label;
+ }
+ *labels = nla_labels;
+ return 0;
+}
+
+static int rtm_to_route_config(struct sk_buff *skb, struct nlmsghdr *nlh,
+ struct mpls_route_config *cfg)
+{
+ struct rtmsg *rtm;
+ struct nlattr *tb[RTA_MAX+1];
+ int index;
+ int err;
+
+ err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_mpls_policy);
+ if (err < 0)
+ goto errout;
+
+ err = -EINVAL;
+ rtm = nlmsg_data(nlh);
+ memset(cfg, 0, sizeof(*cfg));
+
+ if (rtm->rtm_family != AF_MPLS)
+ goto errout;
+ if (rtm->rtm_dst_len != 20)
+ goto errout;
+ if (rtm->rtm_src_len != 0)
+ goto errout;
+ if (rtm->rtm_tos != 0)
+ goto errout;
+ if (rtm->rtm_table != RT_TABLE_MAIN)
+ goto errout;
+ /* Any value is acceptable for rtm_protocol */
+
+ /* As mpls uses destination specific addresses
+ * (or source specific address in the case of multicast)
+ * all addresses have universal scope.
+ */
+ if (rtm->rtm_scope != RT_SCOPE_UNIVERSE)
+ goto errout;
+ if (rtm->rtm_type != RTN_UNICAST)
+ goto errout;
+ if (rtm->rtm_flags != 0)
+ goto errout;
+
+ cfg->rc_label = LABEL_NOT_SPECIFIED;
+ cfg->rc_protocol = rtm->rtm_protocol;
+ cfg->rc_nlflags = nlh->nlmsg_flags;
+ cfg->rc_nlinfo.portid = NETLINK_CB(skb).portid;
+ cfg->rc_nlinfo.nlh = nlh;
+ cfg->rc_nlinfo.nl_net = sock_net(skb->sk);
+
+ for (index = 0; index <= RTA_MAX; index++) {
+ struct nlattr *nla = tb[index];
+ if (!nla)
+ continue;
+
+ switch(index) {
+ case RTA_OIF:
+ cfg->rc_ifindex = nla_get_u32(nla);
+ break;
+ case RTA_NEWDST:
+ if (nla_get_labels(nla, MAX_NEW_LABELS,
+ &cfg->rc_output_labels,
+ cfg->rc_output_label))
+ goto errout;
+ break;
+ case RTA_DST:
+ {
+ u32 label_count;
+ if (nla_get_labels(nla, 1, &label_count,
+ &cfg->rc_label))
+ goto errout;
+
+ /* The first 16 labels are reserved, and may not be set */
+ if (cfg->rc_label < 16)
+ goto errout;
+
+ break;
+ }
+ case RTA_VIA:
+ {
+ struct rtvia *via = nla_data(nla);
+ if (nla_len(nla) < offsetof(struct rtvia, rtvia_addr))
+ goto errout;
+ cfg->rc_via_alen = nla_len(nla) -
+ offsetof(struct rtvia, rtvia_addr);
+ if (cfg->rc_via_alen > MAX_VIA_ALEN)
+ goto errout;
+
+ /* Validate the address family */
+ switch(via->rtvia_family) {
+ case AF_PACKET:
+ cfg->rc_via_table = NEIGH_LINK_TABLE;
+ break;
+ case AF_INET:
+ cfg->rc_via_table = NEIGH_ARP_TABLE;
+ if (cfg->rc_via_alen != 4)
+ goto errout;
+ break;
+ case AF_INET6:
+ cfg->rc_via_table = NEIGH_ND_TABLE;
+ if (cfg->rc_via_alen != 16)
+ goto errout;
+ break;
+ default:
+ /* Unsupported address family */
+ goto errout;
+ }
+
+ memcpy(cfg->rc_via, via->rtvia_addr, cfg->rc_via_alen);
+ break;
+ }
+ default:
+ /* Unsupported attribute */
+ goto errout;
+ }
+ }
+
+ err = 0;
+errout:
+ return err;
+}
+
+static int mpls_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh)
+{
+ struct mpls_route_config cfg;
+ int err;
+
+ err = rtm_to_route_config(skb, nlh, &cfg);
+ if (err < 0)
+ return err;
+
+ return mpls_route_del(&cfg);
+}
+
+
+static int mpls_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh)
+{
+ struct mpls_route_config cfg;
+ int err;
+
+ err = rtm_to_route_config(skb, nlh, &cfg);
+ if (err < 0)
+ return err;
+
+ return mpls_route_add(&cfg);
+}
+
+static int mpls_dump_route(struct sk_buff *skb, u32 portid, u32 seq, int event,
+ u32 label, struct mpls_route *rt, int flags)
+{
+ struct net_device *dev;
+ struct nlmsghdr *nlh;
+ struct rtmsg *rtm;
+
+ nlh = nlmsg_put(skb, portid, seq, event, sizeof(*rtm), flags);
+ if (nlh == NULL)
+ return -EMSGSIZE;
+
+ rtm = nlmsg_data(nlh);
+ rtm->rtm_family = AF_MPLS;
+ rtm->rtm_dst_len = 20;
+ rtm->rtm_src_len = 0;
+ rtm->rtm_tos = 0;
+ rtm->rtm_table = RT_TABLE_MAIN;
+ rtm->rtm_protocol = rt->rt_protocol;
+ rtm->rtm_scope = RT_SCOPE_UNIVERSE;
+ rtm->rtm_type = RTN_UNICAST;
+ rtm->rtm_flags = 0;
+
+ if (rt->rt_labels &&
+ nla_put_labels(skb, RTA_NEWDST, rt->rt_labels, rt->rt_label))
+ goto nla_put_failure;
+ if (nla_put_via(skb, rt->rt_via_table, rt->rt_via, rt->rt_via_alen))
+ goto nla_put_failure;
+ dev = rtnl_dereference(rt->rt_dev);
+ if (dev && nla_put_u32(skb, RTA_OIF, dev->ifindex))
+ goto nla_put_failure;
+ if (nla_put_labels(skb, RTA_DST, 1, &label))
+ goto nla_put_failure;
+
+ nlmsg_end(skb, nlh);
+ return 0;
+
+nla_put_failure:
+ nlmsg_cancel(skb, nlh);
+ return -EMSGSIZE;
+}
+
+static int mpls_dump_routes(struct sk_buff *skb, struct netlink_callback *cb)
+{
+ struct net *net = sock_net(skb->sk);
+ struct mpls_route __rcu **platform_label;
+ size_t platform_labels;
+ unsigned int index;
+
+ ASSERT_RTNL();
+
+ index = cb->args[0];
+ if (index < 16)
+ index = 16;
+
+ platform_label = rtnl_dereference(net->mpls.platform_label);
+ platform_labels = net->mpls.platform_labels;
+ for (; index < platform_labels; index++) {
+ struct mpls_route *rt;
+ rt = rtnl_dereference(platform_label[index]);
+ if (!rt)
+ continue;
+
+ if (mpls_dump_route(skb, NETLINK_CB(cb->skb).portid,
+ cb->nlh->nlmsg_seq, RTM_NEWROUTE,
+ index, rt, NLM_F_MULTI) < 0)
+ break;
+ }
+ cb->args[0] = index;
+
+ return skb->len;
+}
+
+static inline size_t lfib_nlmsg_size(struct mpls_route *rt)
+{
+ size_t payload =
+ NLMSG_ALIGN(sizeof(struct rtmsg))
+ + nla_total_size(2 + rt->rt_via_alen) /* RTA_VIA */
+ + nla_total_size(4); /* RTA_DST */
+ if (rt->rt_labels) /* RTA_NEWDST */
+ payload += nla_total_size(rt->rt_labels * 4);
+ if (rt->rt_dev) /* RTA_OIF */
+ payload += nla_total_size(4);
+ return payload;
+}
+
+static void rtmsg_lfib(int event, u32 label, struct mpls_route *rt,
+ struct nlmsghdr *nlh, struct net *net, u32 portid,
+ unsigned int nlm_flags)
+{
+ struct sk_buff *skb;
+ u32 seq = nlh ? nlh->nlmsg_seq : 0;
+ int err = -ENOBUFS;
+
+ skb = nlmsg_new(lfib_nlmsg_size(rt), GFP_KERNEL);
+ if (skb == NULL)
+ goto errout;
+
+ err = mpls_dump_route(skb, portid, seq, event, label, rt, nlm_flags);
+ if (err < 0) {
+ /* -EMSGSIZE implies BUG in lfib_nlmsg_size */
+ WARN_ON(err == -EMSGSIZE);
+ kfree_skb(skb);
+ goto errout;
+ }
+ rtnl_notify(skb, net, portid, RTNLGRP_MPLS_ROUTE, nlh, GFP_KERNEL);
+
+ return;
+errout:
+ if (err < 0)
+ rtnl_set_sk_err(net, RTNLGRP_MPLS_ROUTE, err);
+}
+
+static int resize_platform_label_table(struct net *net, size_t limit)
+{
+ size_t size = sizeof(struct mpls_route *) * limit;
+ size_t old_limit;
+ size_t cp_size;
+ struct mpls_route __rcu **labels = NULL, **old;
+ struct mpls_route *rt0 = NULL, *rt2 = NULL;
+ unsigned index;
+
+ if (size) {
+ labels = kzalloc(size, GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY);
+ if (!labels)
+ labels = vzalloc(size);
+
+ if (!labels)
+ goto nolabels;
+ }
+
+ /* In case the predefined labels need to be populated */
+ if (limit > LABEL_IPV4_EXPLICIT_NULL) {
+ struct net_device *lo = net->loopback_dev;
+ rt0 = mpls_rt_alloc(lo->addr_len);
+ if (!rt0)
+ goto nort0;
+ RCU_INIT_POINTER(rt0->rt_dev, lo);
+ rt0->rt_protocol = RTPROT_KERNEL;
+ rt0->rt_via_table = NEIGH_LINK_TABLE;
+ memcpy(rt0->rt_via, lo->dev_addr, lo->addr_len);
+ }
+ if (limit > LABEL_IPV6_EXPLICIT_NULL) {
+ struct net_device *lo = net->loopback_dev;
+ rt2 = mpls_rt_alloc(lo->addr_len);
+ if (!rt2)
+ goto nort2;
+ RCU_INIT_POINTER(rt2->rt_dev, lo);
+ rt2->rt_protocol = RTPROT_KERNEL;
+ rt2->rt_via_table = NEIGH_LINK_TABLE;
+ memcpy(rt2->rt_via, lo->dev_addr, lo->addr_len);
+ }
+
+ rtnl_lock();
+ /* Remember the original table */
+ old = rtnl_dereference(net->mpls.platform_label);
+ old_limit = net->mpls.platform_labels;
+
+ /* Free any labels beyond the new table */
+ for (index = limit; index < old_limit; index++)
+ mpls_route_update(net, index, NULL, NULL, NULL);
+
+ /* Copy over the old labels */
+ cp_size = size;
+ if (old_limit < limit)
+ cp_size = old_limit * sizeof(struct mpls_route *);
+
+ memcpy(labels, old, cp_size);
+
+ /* If needed set the predefined labels */
+ if ((old_limit <= LABEL_IPV6_EXPLICIT_NULL) &&
+ (limit > LABEL_IPV6_EXPLICIT_NULL)) {
+ RCU_INIT_POINTER(labels[LABEL_IPV6_EXPLICIT_NULL], rt2);
+ rt2 = NULL;
+ }
+
+ if ((old_limit <= LABEL_IPV4_EXPLICIT_NULL) &&
+ (limit > LABEL_IPV4_EXPLICIT_NULL)) {
+ RCU_INIT_POINTER(labels[LABEL_IPV4_EXPLICIT_NULL], rt0);
+ rt0 = NULL;
+ }
+
+ /* Update the global pointers */
+ net->mpls.platform_labels = limit;
+ rcu_assign_pointer(net->mpls.platform_label, labels);
+
+ rtnl_unlock();
+
+ mpls_rt_free(rt2);
+ mpls_rt_free(rt0);
+
+ if (old) {
+ synchronize_rcu();
+ kvfree(old);
+ }
+ return 0;
+
+nort2:
+ mpls_rt_free(rt0);
+nort0:
+ kvfree(labels);
+nolabels:
+ return -ENOMEM;
+}
+
+static int mpls_platform_labels(struct ctl_table *table, int write,
+ void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+ struct net *net = table->data;
+ int platform_labels = net->mpls.platform_labels;
+ int ret;
+ struct ctl_table tmp = {
+ .procname = table->procname,
+ .data = &platform_labels,
+ .maxlen = sizeof(int),
+ .mode = table->mode,
+ .extra1 = &zero,
+ .extra2 = &label_limit,
+ };
+
+ ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
+
+ if (write && ret == 0)
+ ret = resize_platform_label_table(net, platform_labels);
+
+ return ret;
+}
+
+static struct ctl_table mpls_table[] = {
+ {
+ .procname = "platform_labels",
+ .data = NULL,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = mpls_platform_labels,
+ },
+ { }
+};
+
+static int mpls_net_init(struct net *net)
+{
+ struct ctl_table *table;
+
+ net->mpls.platform_labels = 0;
+ net->mpls.platform_label = NULL;
+
+ table = kmemdup(mpls_table, sizeof(mpls_table), GFP_KERNEL);
+ if (table == NULL)
+ return -ENOMEM;
+
+ table[0].data = net;
+ net->mpls.ctl = register_net_sysctl(net, "net/mpls", table);
+ if (net->mpls.ctl == NULL)
+ return -ENOMEM;
+
+ return 0;
+}
+
+static void mpls_net_exit(struct net *net)
+{
+ struct mpls_route __rcu **platform_label;
+ size_t platform_labels;
+ struct ctl_table *table;
+ unsigned int index;
+
+ table = net->mpls.ctl->ctl_table_arg;
+ unregister_net_sysctl_table(net->mpls.ctl);
+ kfree(table);
+
+ /* An rcu grace period has passed since there was a device in
+ * the network namespace (and thus the last in flight packet)
+ * left this network namespace. This is because
+ * unregister_netdevice_many and netdev_run_todo has completed
+ * for each network device that was in this network namespace.
+ *
+ * As such no additional rcu synchronization is necessary when
+ * freeing the platform_label table.
+ */
+ rtnl_lock();
+ platform_label = rtnl_dereference(net->mpls.platform_label);
+ platform_labels = net->mpls.platform_labels;
+ for (index = 0; index < platform_labels; index++) {
+ struct mpls_route *rt = rtnl_dereference(platform_label[index]);
+ RCU_INIT_POINTER(platform_label[index], NULL);
+ mpls_rt_free(rt);
+ }
+ rtnl_unlock();
+
+ kvfree(platform_label);
+}
+
+static struct pernet_operations mpls_net_ops = {
+ .init = mpls_net_init,
+ .exit = mpls_net_exit,
+};
+
+static int __init mpls_init(void)
+{
+ int err;
+
+ BUILD_BUG_ON(sizeof(struct mpls_shim_hdr) != 4);
+
+ err = register_pernet_subsys(&mpls_net_ops);
+ if (err)
+ goto out;
+
+ err = register_netdevice_notifier(&mpls_dev_notifier);
+ if (err)
+ goto out_unregister_pernet;
+
+ dev_add_pack(&mpls_packet_type);
+
+ rtnl_register(PF_MPLS, RTM_NEWROUTE, mpls_rtm_newroute, NULL, NULL);
+ rtnl_register(PF_MPLS, RTM_DELROUTE, mpls_rtm_delroute, NULL, NULL);
+ rtnl_register(PF_MPLS, RTM_GETROUTE, NULL, mpls_dump_routes, NULL);
+ err = 0;
+out:
+ return err;
+
+out_unregister_pernet:
+ unregister_pernet_subsys(&mpls_net_ops);
+ goto out;
+}
+module_init(mpls_init);
+
+static void __exit mpls_exit(void)
+{
+ rtnl_unregister_all(PF_MPLS);
+ dev_remove_pack(&mpls_packet_type);
+ unregister_netdevice_notifier(&mpls_dev_notifier);
+ unregister_pernet_subsys(&mpls_net_ops);
+}
+module_exit(mpls_exit);
+
+MODULE_DESCRIPTION("MultiProtocol Label Switching");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS_NETPROTO(PF_MPLS);
diff --git a/net/mpls/internal.h b/net/mpls/internal.h
new file mode 100644
index 000000000000..fb6de92052c4
--- /dev/null
+++ b/net/mpls/internal.h
@@ -0,0 +1,59 @@
+#ifndef MPLS_INTERNAL_H
+#define MPLS_INTERNAL_H
+
+#define LABEL_IPV4_EXPLICIT_NULL 0 /* RFC3032 */
+#define LABEL_ROUTER_ALERT_LABEL 1 /* RFC3032 */
+#define LABEL_IPV6_EXPLICIT_NULL 2 /* RFC3032 */
+#define LABEL_IMPLICIT_NULL 3 /* RFC3032 */
+#define LABEL_ENTROPY_INDICATOR 7 /* RFC6790 */
+#define LABEL_GAL 13 /* RFC5586 */
+#define LABEL_OAM_ALERT 14 /* RFC3429 */
+#define LABEL_EXTENSION 15 /* RFC7274 */
+
+
+struct mpls_shim_hdr {
+ __be32 label_stack_entry;
+};
+
+struct mpls_entry_decoded {
+ u32 label;
+ u8 ttl;
+ u8 tc;
+ u8 bos;
+};
+
+struct sk_buff;
+
+static inline struct mpls_shim_hdr *mpls_hdr(const struct sk_buff *skb)
+{
+ return (struct mpls_shim_hdr *)skb_network_header(skb);
+}
+
+static inline struct mpls_shim_hdr mpls_entry_encode(u32 label, unsigned ttl, unsigned tc, bool bos)
+{
+ struct mpls_shim_hdr result;
+ result.label_stack_entry =
+ cpu_to_be32((label << MPLS_LS_LABEL_SHIFT) |
+ (tc << MPLS_LS_TC_SHIFT) |
+ (bos ? (1 << MPLS_LS_S_SHIFT) : 0) |
+ (ttl << MPLS_LS_TTL_SHIFT));
+ return result;
+}
+
+static inline struct mpls_entry_decoded mpls_entry_decode(struct mpls_shim_hdr *hdr)
+{
+ struct mpls_entry_decoded result;
+ unsigned entry = be32_to_cpu(hdr->label_stack_entry);
+
+ result.label = (entry & MPLS_LS_LABEL_MASK) >> MPLS_LS_LABEL_SHIFT;
+ result.ttl = (entry & MPLS_LS_TTL_MASK) >> MPLS_LS_TTL_SHIFT;
+ result.tc = (entry & MPLS_LS_TC_MASK) >> MPLS_LS_TC_SHIFT;
+ result.bos = (entry & MPLS_LS_S_MASK) >> MPLS_LS_S_SHIFT;
+
+ return result;
+}
+
+int nla_put_labels(struct sk_buff *skb, int attrtype, u8 labels, const u32 label[]);
+int nla_get_labels(const struct nlattr *nla, u32 max_labels, u32 *labels, u32 label[]);
+
+#endif /* MPLS_INTERNAL_H */