--- /dev/null
+/*
+ * vrf.c: device driver to encapsulate a VRF space
+ *
+ * Copyright (c) 2015 Cumulus Networks. All rights reserved.
+ * Copyright (c) 2015 Shrijeet Mukherjee <shm@cumulusnetworks.com>
+ * Copyright (c) 2015 David Ahern <dsa@cumulusnetworks.com>
+ *
+ * Based on dummy, team and ipvlan drivers
+ *
+ * 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/module.h>
+#include <linux/kernel.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/ip.h>
+#include <linux/init.h>
+#include <linux/moduleparam.h>
+#include <linux/netfilter.h>
+#include <linux/rtnetlink.h>
+#include <net/rtnetlink.h>
+#include <linux/u64_stats_sync.h>
+#include <linux/hashtable.h>
+
+#include <linux/inetdevice.h>
+#include <net/ip.h>
+#include <net/ip_fib.h>
+#include <net/ip6_route.h>
+#include <net/rtnetlink.h>
+#include <net/route.h>
+#include <net/addrconf.h>
+#include <net/vrf.h>
+
+#define DRV_NAME "vrf"
+#define DRV_VERSION "1.0"
+
+#define vrf_is_slave(dev) ((dev)->flags & IFF_SLAVE)
+
+#define vrf_master_get_rcu(dev) \
+ ((struct net_device *)rcu_dereference(dev->rx_handler_data))
+
+struct pcpu_dstats {
+ u64 tx_pkts;
+ u64 tx_bytes;
+ u64 tx_drps;
+ u64 rx_pkts;
+ u64 rx_bytes;
+ struct u64_stats_sync syncp;
+};
+
+static struct dst_entry *vrf_ip_check(struct dst_entry *dst, u32 cookie)
+{
+ return dst;
+}
+
+static int vrf_ip_local_out(struct sk_buff *skb)
+{
+ return ip_local_out(skb);
+}
+
+static unsigned int vrf_v4_mtu(const struct dst_entry *dst)
+{
+ /* TO-DO: return max ethernet size? */
+ return dst->dev->mtu;
+}
+
+static void vrf_dst_destroy(struct dst_entry *dst)
+{
+ /* our dst lives forever - or until the device is closed */
+}
+
+static unsigned int vrf_default_advmss(const struct dst_entry *dst)
+{
+ return 65535 - 40;
+}
+
+static struct dst_ops vrf_dst_ops = {
+ .family = AF_INET,
+ .local_out = vrf_ip_local_out,
+ .check = vrf_ip_check,
+ .mtu = vrf_v4_mtu,
+ .destroy = vrf_dst_destroy,
+ .default_advmss = vrf_default_advmss,
+};
+
+static bool is_ip_rx_frame(struct sk_buff *skb)
+{
+ switch (skb->protocol) {
+ case htons(ETH_P_IP):
+ case htons(ETH_P_IPV6):
+ return true;
+ }
+ return false;
+}
+
+/* note: already called with rcu_read_lock */
+static rx_handler_result_t vrf_handle_frame(struct sk_buff **pskb)
+{
+ struct sk_buff *skb = *pskb;
+
+ if (is_ip_rx_frame(skb)) {
+ struct net_device *dev = vrf_master_get_rcu(skb->dev);
+ struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
+
+ u64_stats_update_begin(&dstats->syncp);
+ dstats->rx_pkts++;
+ dstats->rx_bytes += skb->len;
+ u64_stats_update_end(&dstats->syncp);
+
+ skb->dev = dev;
+
+ return RX_HANDLER_ANOTHER;
+ }
+ return RX_HANDLER_PASS;
+}
+
+static struct rtnl_link_stats64 *vrf_get_stats64(struct net_device *dev,
+ struct rtnl_link_stats64 *stats)
+{
+ int i;
+
+ for_each_possible_cpu(i) {
+ const struct pcpu_dstats *dstats;
+ u64 tbytes, tpkts, tdrops, rbytes, rpkts;
+ unsigned int start;
+
+ dstats = per_cpu_ptr(dev->dstats, i);
+ do {
+ start = u64_stats_fetch_begin_irq(&dstats->syncp);
+ tbytes = dstats->tx_bytes;
+ tpkts = dstats->tx_pkts;
+ tdrops = dstats->tx_drps;
+ rbytes = dstats->rx_bytes;
+ rpkts = dstats->rx_pkts;
+ } while (u64_stats_fetch_retry_irq(&dstats->syncp, start));
+ stats->tx_bytes += tbytes;
+ stats->tx_packets += tpkts;
+ stats->tx_dropped += tdrops;
+ stats->rx_bytes += rbytes;
+ stats->rx_packets += rpkts;
+ }
+ return stats;
+}
+
+static netdev_tx_t vrf_process_v6_outbound(struct sk_buff *skb,
+ struct net_device *dev)
+{
+ return 0;
+}
+
+static int vrf_send_v4_prep(struct sk_buff *skb, struct flowi4 *fl4,
+ struct net_device *vrf_dev)
+{
+ struct rtable *rt;
+ int err = 1;
+
+ rt = ip_route_output_flow(dev_net(vrf_dev), fl4, NULL);
+ if (IS_ERR(rt))
+ goto out;
+
+ /* TO-DO: what about broadcast ? */
+ if (rt->rt_type != RTN_UNICAST && rt->rt_type != RTN_LOCAL) {
+ ip_rt_put(rt);
+ goto out;
+ }
+
+ skb_dst_drop(skb);
+ skb_dst_set(skb, &rt->dst);
+ err = 0;
+out:
+ return err;
+}
+
+static netdev_tx_t vrf_process_v4_outbound(struct sk_buff *skb,
+ struct net_device *vrf_dev)
+{
+ struct iphdr *ip4h = ip_hdr(skb);
+ int ret = NET_XMIT_DROP;
+ struct flowi4 fl4 = {
+ /* needed to match OIF rule */
+ .flowi4_oif = vrf_dev->ifindex,
+ .flowi4_iif = LOOPBACK_IFINDEX,
+ .flowi4_tos = RT_TOS(ip4h->tos),
+ .flowi4_flags = FLOWI_FLAG_ANYSRC | FLOWI_FLAG_VRFSRC,
+ .daddr = ip4h->daddr,
+ };
+
+ if (vrf_send_v4_prep(skb, &fl4, vrf_dev))
+ goto err;
+
+ if (!ip4h->saddr) {
+ ip4h->saddr = inet_select_addr(skb_dst(skb)->dev, 0,
+ RT_SCOPE_LINK);
+ }
+
+ ret = ip_local_out(skb);
+ if (unlikely(net_xmit_eval(ret)))
+ vrf_dev->stats.tx_errors++;
+ else
+ ret = NET_XMIT_SUCCESS;
+
+out:
+ return ret;
+err:
+ vrf_dev->stats.tx_errors++;
+ kfree_skb(skb);
+ goto out;
+}
+
+static netdev_tx_t is_ip_tx_frame(struct sk_buff *skb, struct net_device *dev)
+{
+ switch (skb->protocol) {
+ case htons(ETH_P_IP):
+ return vrf_process_v4_outbound(skb, dev);
+ case htons(ETH_P_IPV6):
+ return vrf_process_v6_outbound(skb, dev);
+ default:
+ return NET_XMIT_DROP;
+ }
+}
+
+static netdev_tx_t vrf_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+ netdev_tx_t ret = is_ip_tx_frame(skb, dev);
+
+ if (likely(ret == NET_XMIT_SUCCESS || ret == NET_XMIT_CN)) {
+ struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
+
+ u64_stats_update_begin(&dstats->syncp);
+ dstats->tx_pkts++;
+ dstats->tx_bytes += skb->len;
+ u64_stats_update_end(&dstats->syncp);
+ } else {
+ this_cpu_inc(dev->dstats->tx_drps);
+ }
+
+ return ret;
+}
+
+static netdev_tx_t vrf_finish(struct sock *sk, struct sk_buff *skb)
+{
+ return dev_queue_xmit(skb);
+}
+
+static int vrf_output(struct sock *sk, struct sk_buff *skb)
+{
+ struct net_device *dev = skb_dst(skb)->dev;
+
+ IP_UPD_PO_STATS(dev_net(dev), IPSTATS_MIB_OUT, skb->len);
+
+ skb->dev = dev;
+ skb->protocol = htons(ETH_P_IP);
+
+ return NF_HOOK_COND(NFPROTO_IPV4, NF_INET_POST_ROUTING, sk, skb,
+ NULL, dev,
+ vrf_finish,
+ !(IPCB(skb)->flags & IPSKB_REROUTED));
+}
+
+static void vrf_rtable_destroy(struct net_vrf *vrf)
+{
+ struct dst_entry *dst = (struct dst_entry *)vrf->rth;
+
+ if (dst)
+ dst_destroy(dst);
+ vrf->rth = NULL;
+}
+
+static struct rtable *vrf_rtable_create(struct net_device *dev)
+{
+ struct rtable *rth;
+
+ rth = dst_alloc(&vrf_dst_ops, dev, 2,
+ DST_OBSOLETE_NONE,
+ (DST_HOST | DST_NOPOLICY | DST_NOXFRM));
+ if (rth) {
+ rth->dst.output = vrf_output;
+ rth->rt_genid = rt_genid_ipv4(dev_net(dev));
+ rth->rt_flags = 0;
+ rth->rt_type = RTN_UNICAST;
+ rth->rt_is_input = 0;
+ rth->rt_iif = 0;
+ rth->rt_pmtu = 0;
+ rth->rt_gateway = 0;
+ rth->rt_uses_gateway = 0;
+ INIT_LIST_HEAD(&rth->rt_uncached);
+ rth->rt_uncached_list = NULL;
+ rth->rt_lwtstate = NULL;
+ }
+
+ return rth;
+}
+
+/**************************** device handling ********************/
+
+/* cycle interface to flush neighbor cache and move routes across tables */
+static void cycle_netdev(struct net_device *dev)
+{
+ unsigned int flags = dev->flags;
+ int ret;
+
+ if (!netif_running(dev))
+ return;
+
+ ret = dev_change_flags(dev, flags & ~IFF_UP);
+ if (ret >= 0)
+ ret = dev_change_flags(dev, flags);
+
+ if (ret < 0) {
+ netdev_err(dev,
+ "Failed to cycle device %s; route tables might be wrong!\n",
+ dev->name);
+ }
+}
+
+static struct slave *__vrf_find_slave_dev(struct slave_queue *queue,
+ struct net_device *dev)
+{
+ struct list_head *head = &queue->all_slaves;
+ struct slave *slave;
+
+ list_for_each_entry(slave, head, list) {
+ if (slave->dev == dev)
+ return slave;
+ }
+
+ return NULL;
+}
+
+/* inverse of __vrf_insert_slave */
+static void __vrf_remove_slave(struct slave_queue *queue, struct slave *slave)
+{
+ dev_put(slave->dev);
+ list_del(&slave->list);
+ queue->num_slaves--;
+}
+
+static void __vrf_insert_slave(struct slave_queue *queue, struct slave *slave)
+{
+ dev_hold(slave->dev);
+ list_add(&slave->list, &queue->all_slaves);
+ queue->num_slaves++;
+}
+
+static int do_vrf_add_slave(struct net_device *dev, struct net_device *port_dev)
+{
+ struct net_vrf_dev *vrf_ptr = kmalloc(sizeof(*vrf_ptr), GFP_KERNEL);
+ struct slave *slave = kzalloc(sizeof(*slave), GFP_KERNEL);
+ struct slave *duplicate_slave;
+ struct net_vrf *vrf = netdev_priv(dev);
+ struct slave_queue *queue = &vrf->queue;
+ int ret = -ENOMEM;
+
+ if (!slave || !vrf_ptr)
+ goto out_fail;
+
+ slave->dev = port_dev;
+
+ vrf_ptr->ifindex = dev->ifindex;
+ vrf_ptr->tb_id = vrf->tb_id;
+
+ duplicate_slave = __vrf_find_slave_dev(queue, port_dev);
+ if (duplicate_slave) {
+ ret = -EBUSY;
+ goto out_fail;
+ }
+
+ __vrf_insert_slave(queue, slave);
+
+ /* register the packet handler for slave ports */
+ ret = netdev_rx_handler_register(port_dev, vrf_handle_frame, dev);
+ if (ret) {
+ netdev_err(port_dev,
+ "Device %s failed to register rx_handler\n",
+ port_dev->name);
+ goto out_remove;
+ }
+
+ ret = netdev_master_upper_dev_link(port_dev, dev);
+ if (ret < 0)
+ goto out_unregister;
+
+ port_dev->flags |= IFF_SLAVE;
+
+ rcu_assign_pointer(port_dev->vrf_ptr, vrf_ptr);
+ cycle_netdev(port_dev);
+
+ return 0;
+
+out_unregister:
+ netdev_rx_handler_unregister(port_dev);
+out_remove:
+ __vrf_remove_slave(queue, slave);
+out_fail:
+ kfree(vrf_ptr);
+ kfree(slave);
+ return ret;
+}
+
+static int vrf_add_slave(struct net_device *dev, struct net_device *port_dev)
+{
+ if (!netif_is_vrf(dev) || netif_is_vrf(port_dev) ||
+ vrf_is_slave(port_dev))
+ return -EINVAL;
+
+ return do_vrf_add_slave(dev, port_dev);
+}
+
+/* inverse of do_vrf_add_slave */
+static int do_vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
+{
+ struct net_vrf_dev *vrf_ptr = rtnl_dereference(port_dev->vrf_ptr);
+ struct net_vrf *vrf = netdev_priv(dev);
+ struct slave_queue *queue = &vrf->queue;
+ struct slave *slave;
+
+ RCU_INIT_POINTER(port_dev->vrf_ptr, NULL);
+
+ netdev_upper_dev_unlink(port_dev, dev);
+ port_dev->flags &= ~IFF_SLAVE;
+
+ netdev_rx_handler_unregister(port_dev);
+
+ /* after netdev_rx_handler_unregister for synchronize_rcu */
+ kfree(vrf_ptr);
+
+ cycle_netdev(port_dev);
+
+ slave = __vrf_find_slave_dev(queue, port_dev);
+ if (slave)
+ __vrf_remove_slave(queue, slave);
+
+ kfree(slave);
+
+ return 0;
+}
+
+static int vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
+{
+ if (!netif_is_vrf(dev))
+ return -EINVAL;
+
+ return do_vrf_del_slave(dev, port_dev);
+}
+
+static void vrf_dev_uninit(struct net_device *dev)
+{
+ struct net_vrf *vrf = netdev_priv(dev);
+ struct slave_queue *queue = &vrf->queue;
+ struct list_head *head = &queue->all_slaves;
+ struct slave *slave, *next;
+
+ vrf_rtable_destroy(vrf);
+
+ list_for_each_entry_safe(slave, next, head, list)
+ vrf_del_slave(dev, slave->dev);
+
+ if (dev->dstats)
+ free_percpu(dev->dstats);
+ dev->dstats = NULL;
+}
+
+static int vrf_dev_init(struct net_device *dev)
+{
+ struct net_vrf *vrf = netdev_priv(dev);
+
+ INIT_LIST_HEAD(&vrf->queue.all_slaves);
+
+ dev->dstats = netdev_alloc_pcpu_stats(struct pcpu_dstats);
+ if (!dev->dstats)
+ goto out_nomem;
+
+ /* create the default dst which points back to us */
+ vrf->rth = vrf_rtable_create(dev);
+ if (!vrf->rth)
+ goto out_stats;
+
+ dev->flags = IFF_MASTER | IFF_NOARP;
+
+ return 0;
+
+out_stats:
+ free_percpu(dev->dstats);
+ dev->dstats = NULL;
+out_nomem:
+ return -ENOMEM;
+}
+
+static const struct net_device_ops vrf_netdev_ops = {
+ .ndo_init = vrf_dev_init,
+ .ndo_uninit = vrf_dev_uninit,
+ .ndo_start_xmit = vrf_xmit,
+ .ndo_get_stats64 = vrf_get_stats64,
+ .ndo_add_slave = vrf_add_slave,
+ .ndo_del_slave = vrf_del_slave,
+};
+
+static void vrf_get_drvinfo(struct net_device *dev,
+ struct ethtool_drvinfo *info)
+{
+ strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
+ strlcpy(info->version, DRV_VERSION, sizeof(info->version));
+}
+
+static const struct ethtool_ops vrf_ethtool_ops = {
+ .get_drvinfo = vrf_get_drvinfo,
+};
+
+static void vrf_setup(struct net_device *dev)
+{
+ ether_setup(dev);
+
+ /* Initialize the device structure. */
+ dev->netdev_ops = &vrf_netdev_ops;
+ dev->ethtool_ops = &vrf_ethtool_ops;
+ dev->destructor = free_netdev;
+
+ /* Fill in device structure with ethernet-generic values. */
+ eth_hw_addr_random(dev);
+
+ /* don't acquire vrf device's netif_tx_lock when transmitting */
+ dev->features |= NETIF_F_LLTX;
+
+ /* don't allow vrf devices to change network namespaces. */
+ dev->features |= NETIF_F_NETNS_LOCAL;
+}
+
+static int vrf_validate(struct nlattr *tb[], struct nlattr *data[])
+{
+ 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;
+ }
+ return 0;
+}
+
+static void vrf_dellink(struct net_device *dev, struct list_head *head)
+{
+ struct net_vrf_dev *vrf_ptr = rtnl_dereference(dev->vrf_ptr);
+
+ RCU_INIT_POINTER(dev->vrf_ptr, NULL);
+ kfree_rcu(vrf_ptr, rcu);
+ unregister_netdevice_queue(dev, head);
+}
+
+static int vrf_newlink(struct net *src_net, struct net_device *dev,
+ struct nlattr *tb[], struct nlattr *data[])
+{
+ struct net_vrf *vrf = netdev_priv(dev);
+ struct net_vrf_dev *vrf_ptr;
+ int err;
+
+ if (!data || !data[IFLA_VRF_TABLE])
+ return -EINVAL;
+
+ vrf->tb_id = nla_get_u32(data[IFLA_VRF_TABLE]);
+
+ dev->priv_flags |= IFF_VRF_MASTER;
+
+ err = -ENOMEM;
+ vrf_ptr = kmalloc(sizeof(*dev->vrf_ptr), GFP_KERNEL);
+ if (!vrf_ptr)
+ goto out_fail;
+
+ vrf_ptr->ifindex = dev->ifindex;
+ vrf_ptr->tb_id = vrf->tb_id;
+
+ err = register_netdevice(dev);
+ if (err < 0)
+ goto out_fail;
+
+ rcu_assign_pointer(dev->vrf_ptr, vrf_ptr);
+
+ return 0;
+
+out_fail:
+ kfree(vrf_ptr);
+ free_netdev(dev);
+ return err;
+}
+
+static size_t vrf_nl_getsize(const struct net_device *dev)
+{
+ return nla_total_size(sizeof(u32)); /* IFLA_VRF_TABLE */
+}
+
+static int vrf_fillinfo(struct sk_buff *skb,
+ const struct net_device *dev)
+{
+ struct net_vrf *vrf = netdev_priv(dev);
+
+ return nla_put_u32(skb, IFLA_VRF_TABLE, vrf->tb_id);
+}
+
+static const struct nla_policy vrf_nl_policy[IFLA_VRF_MAX + 1] = {
+ [IFLA_VRF_TABLE] = { .type = NLA_U32 },
+};
+
+static struct rtnl_link_ops vrf_link_ops __read_mostly = {
+ .kind = DRV_NAME,
+ .priv_size = sizeof(struct net_vrf),
+
+ .get_size = vrf_nl_getsize,
+ .policy = vrf_nl_policy,
+ .validate = vrf_validate,
+ .fill_info = vrf_fillinfo,
+
+ .newlink = vrf_newlink,
+ .dellink = vrf_dellink,
+ .setup = vrf_setup,
+ .maxtype = IFLA_VRF_MAX,
+};
+
+static int vrf_device_event(struct notifier_block *unused,
+ unsigned long event, void *ptr)
+{
+ struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+
+ /* only care about unregister events to drop slave references */
+ if (event == NETDEV_UNREGISTER) {
+ struct net_vrf_dev *vrf_ptr = rtnl_dereference(dev->vrf_ptr);
+ struct net_device *vrf_dev;
+
+ if (!vrf_ptr || netif_is_vrf(dev))
+ goto out;
+
+ vrf_dev = __dev_get_by_index(dev_net(dev), vrf_ptr->ifindex);
+ if (vrf_dev)
+ vrf_del_slave(vrf_dev, dev);
+ }
+out:
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block vrf_notifier_block __read_mostly = {
+ .notifier_call = vrf_device_event,
+};
+
+static int __init vrf_init_module(void)
+{
+ int rc;
+
+ vrf_dst_ops.kmem_cachep =
+ kmem_cache_create("vrf_ip_dst_cache",
+ sizeof(struct rtable), 0,
+ SLAB_HWCACHE_ALIGN | SLAB_PANIC,
+ NULL);
+
+ if (!vrf_dst_ops.kmem_cachep)
+ return -ENOMEM;
+
+ register_netdevice_notifier(&vrf_notifier_block);
+
+ rc = rtnl_link_register(&vrf_link_ops);
+ if (rc < 0)
+ goto error;
+
+ return 0;
+
+error:
+ unregister_netdevice_notifier(&vrf_notifier_block);
+ kmem_cache_destroy(vrf_dst_ops.kmem_cachep);
+ return rc;
+}
+
+static void __exit vrf_cleanup_module(void)
+{
+ rtnl_link_unregister(&vrf_link_ops);
+ unregister_netdevice_notifier(&vrf_notifier_block);
+ kmem_cache_destroy(vrf_dst_ops.kmem_cachep);
+}
+
+module_init(vrf_init_module);
+module_exit(vrf_cleanup_module);
+MODULE_AUTHOR("Shrijeet Mukherjee, David Ahern");
+MODULE_DESCRIPTION("Device driver to instantiate VRF domains");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_RTNL_LINK(DRV_NAME);
+MODULE_VERSION(DRV_VERSION);
projects / platform / kernel / linux-exynos.git / commitdiff