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-rw-r--r--net/phonet/pn_dev.c419
1 files changed, 419 insertions, 0 deletions
diff --git a/net/phonet/pn_dev.c b/net/phonet/pn_dev.c
new file mode 100644
index 000000000..cde671d29
--- /dev/null
+++ b/net/phonet/pn_dev.c
@@ -0,0 +1,419 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * File: pn_dev.c
+ *
+ * Phonet network device
+ *
+ * Copyright (C) 2008 Nokia Corporation.
+ *
+ * Authors: Sakari Ailus <sakari.ailus@nokia.com>
+ * RĂ©mi Denis-Courmont
+ */
+
+#include <linux/kernel.h>
+#include <linux/net.h>
+#include <linux/slab.h>
+#include <linux/netdevice.h>
+#include <linux/phonet.h>
+#include <linux/proc_fs.h>
+#include <linux/if_arp.h>
+#include <net/sock.h>
+#include <net/netns/generic.h>
+#include <net/phonet/pn_dev.h>
+
+struct phonet_routes {
+ struct mutex lock;
+ struct net_device __rcu *table[64];
+};
+
+struct phonet_net {
+ struct phonet_device_list pndevs;
+ struct phonet_routes routes;
+};
+
+static unsigned int phonet_net_id __read_mostly;
+
+static struct phonet_net *phonet_pernet(struct net *net)
+{
+ return net_generic(net, phonet_net_id);
+}
+
+struct phonet_device_list *phonet_device_list(struct net *net)
+{
+ struct phonet_net *pnn = phonet_pernet(net);
+ return &pnn->pndevs;
+}
+
+/* Allocate new Phonet device. */
+static struct phonet_device *__phonet_device_alloc(struct net_device *dev)
+{
+ struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
+ struct phonet_device *pnd = kmalloc(sizeof(*pnd), GFP_ATOMIC);
+ if (pnd == NULL)
+ return NULL;
+ pnd->netdev = dev;
+ bitmap_zero(pnd->addrs, 64);
+
+ BUG_ON(!mutex_is_locked(&pndevs->lock));
+ list_add_rcu(&pnd->list, &pndevs->list);
+ return pnd;
+}
+
+static struct phonet_device *__phonet_get(struct net_device *dev)
+{
+ struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
+ struct phonet_device *pnd;
+
+ BUG_ON(!mutex_is_locked(&pndevs->lock));
+ list_for_each_entry(pnd, &pndevs->list, list) {
+ if (pnd->netdev == dev)
+ return pnd;
+ }
+ return NULL;
+}
+
+static struct phonet_device *__phonet_get_rcu(struct net_device *dev)
+{
+ struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
+ struct phonet_device *pnd;
+
+ list_for_each_entry_rcu(pnd, &pndevs->list, list) {
+ if (pnd->netdev == dev)
+ return pnd;
+ }
+ return NULL;
+}
+
+static void phonet_device_destroy(struct net_device *dev)
+{
+ struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
+ struct phonet_device *pnd;
+
+ ASSERT_RTNL();
+
+ mutex_lock(&pndevs->lock);
+ pnd = __phonet_get(dev);
+ if (pnd)
+ list_del_rcu(&pnd->list);
+ mutex_unlock(&pndevs->lock);
+
+ if (pnd) {
+ u8 addr;
+
+ for_each_set_bit(addr, pnd->addrs, 64)
+ phonet_address_notify(RTM_DELADDR, dev, addr);
+ kfree(pnd);
+ }
+}
+
+struct net_device *phonet_device_get(struct net *net)
+{
+ struct phonet_device_list *pndevs = phonet_device_list(net);
+ struct phonet_device *pnd;
+ struct net_device *dev = NULL;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(pnd, &pndevs->list, list) {
+ dev = pnd->netdev;
+ BUG_ON(!dev);
+
+ if ((dev->reg_state == NETREG_REGISTERED) &&
+ ((pnd->netdev->flags & IFF_UP)) == IFF_UP)
+ break;
+ dev = NULL;
+ }
+ dev_hold(dev);
+ rcu_read_unlock();
+ return dev;
+}
+
+int phonet_address_add(struct net_device *dev, u8 addr)
+{
+ struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
+ struct phonet_device *pnd;
+ int err = 0;
+
+ mutex_lock(&pndevs->lock);
+ /* Find or create Phonet-specific device data */
+ pnd = __phonet_get(dev);
+ if (pnd == NULL)
+ pnd = __phonet_device_alloc(dev);
+ if (unlikely(pnd == NULL))
+ err = -ENOMEM;
+ else if (test_and_set_bit(addr >> 2, pnd->addrs))
+ err = -EEXIST;
+ mutex_unlock(&pndevs->lock);
+ return err;
+}
+
+int phonet_address_del(struct net_device *dev, u8 addr)
+{
+ struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
+ struct phonet_device *pnd;
+ int err = 0;
+
+ mutex_lock(&pndevs->lock);
+ pnd = __phonet_get(dev);
+ if (!pnd || !test_and_clear_bit(addr >> 2, pnd->addrs)) {
+ err = -EADDRNOTAVAIL;
+ pnd = NULL;
+ } else if (bitmap_empty(pnd->addrs, 64))
+ list_del_rcu(&pnd->list);
+ else
+ pnd = NULL;
+ mutex_unlock(&pndevs->lock);
+
+ if (pnd)
+ kfree_rcu(pnd, rcu);
+
+ return err;
+}
+
+/* Gets a source address toward a destination, through a interface. */
+u8 phonet_address_get(struct net_device *dev, u8 daddr)
+{
+ struct phonet_device *pnd;
+ u8 saddr;
+
+ rcu_read_lock();
+ pnd = __phonet_get_rcu(dev);
+ if (pnd) {
+ BUG_ON(bitmap_empty(pnd->addrs, 64));
+
+ /* Use same source address as destination, if possible */
+ if (test_bit(daddr >> 2, pnd->addrs))
+ saddr = daddr;
+ else
+ saddr = find_first_bit(pnd->addrs, 64) << 2;
+ } else
+ saddr = PN_NO_ADDR;
+ rcu_read_unlock();
+
+ if (saddr == PN_NO_ADDR) {
+ /* Fallback to another device */
+ struct net_device *def_dev;
+
+ def_dev = phonet_device_get(dev_net(dev));
+ if (def_dev) {
+ if (def_dev != dev)
+ saddr = phonet_address_get(def_dev, daddr);
+ dev_put(def_dev);
+ }
+ }
+ return saddr;
+}
+
+int phonet_address_lookup(struct net *net, u8 addr)
+{
+ struct phonet_device_list *pndevs = phonet_device_list(net);
+ struct phonet_device *pnd;
+ int err = -EADDRNOTAVAIL;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(pnd, &pndevs->list, list) {
+ /* Don't allow unregistering devices! */
+ if ((pnd->netdev->reg_state != NETREG_REGISTERED) ||
+ ((pnd->netdev->flags & IFF_UP)) != IFF_UP)
+ continue;
+
+ if (test_bit(addr >> 2, pnd->addrs)) {
+ err = 0;
+ goto found;
+ }
+ }
+found:
+ rcu_read_unlock();
+ return err;
+}
+
+/* automatically configure a Phonet device, if supported */
+static int phonet_device_autoconf(struct net_device *dev)
+{
+ struct if_phonet_req req;
+ int ret;
+
+ if (!dev->netdev_ops->ndo_siocdevprivate)
+ return -EOPNOTSUPP;
+
+ ret = dev->netdev_ops->ndo_siocdevprivate(dev, (struct ifreq *)&req,
+ NULL, SIOCPNGAUTOCONF);
+ if (ret < 0)
+ return ret;
+
+ ASSERT_RTNL();
+ ret = phonet_address_add(dev, req.ifr_phonet_autoconf.device);
+ if (ret)
+ return ret;
+ phonet_address_notify(RTM_NEWADDR, dev,
+ req.ifr_phonet_autoconf.device);
+ return 0;
+}
+
+static void phonet_route_autodel(struct net_device *dev)
+{
+ struct phonet_net *pnn = phonet_pernet(dev_net(dev));
+ unsigned int i;
+ DECLARE_BITMAP(deleted, 64);
+
+ /* Remove left-over Phonet routes */
+ bitmap_zero(deleted, 64);
+ mutex_lock(&pnn->routes.lock);
+ for (i = 0; i < 64; i++)
+ if (rcu_access_pointer(pnn->routes.table[i]) == dev) {
+ RCU_INIT_POINTER(pnn->routes.table[i], NULL);
+ set_bit(i, deleted);
+ }
+ mutex_unlock(&pnn->routes.lock);
+
+ if (bitmap_empty(deleted, 64))
+ return; /* short-circuit RCU */
+ synchronize_rcu();
+ for_each_set_bit(i, deleted, 64) {
+ rtm_phonet_notify(RTM_DELROUTE, dev, i);
+ dev_put(dev);
+ }
+}
+
+/* notify Phonet of device events */
+static int phonet_device_notify(struct notifier_block *me, unsigned long what,
+ void *ptr)
+{
+ struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+
+ switch (what) {
+ case NETDEV_REGISTER:
+ if (dev->type == ARPHRD_PHONET)
+ phonet_device_autoconf(dev);
+ break;
+ case NETDEV_UNREGISTER:
+ phonet_device_destroy(dev);
+ phonet_route_autodel(dev);
+ break;
+ }
+ return 0;
+
+}
+
+static struct notifier_block phonet_device_notifier = {
+ .notifier_call = phonet_device_notify,
+ .priority = 0,
+};
+
+/* Per-namespace Phonet devices handling */
+static int __net_init phonet_init_net(struct net *net)
+{
+ struct phonet_net *pnn = phonet_pernet(net);
+
+ if (!proc_create_net("phonet", 0, net->proc_net, &pn_sock_seq_ops,
+ sizeof(struct seq_net_private)))
+ return -ENOMEM;
+
+ INIT_LIST_HEAD(&pnn->pndevs.list);
+ mutex_init(&pnn->pndevs.lock);
+ mutex_init(&pnn->routes.lock);
+ return 0;
+}
+
+static void __net_exit phonet_exit_net(struct net *net)
+{
+ struct phonet_net *pnn = phonet_pernet(net);
+
+ remove_proc_entry("phonet", net->proc_net);
+ WARN_ON_ONCE(!list_empty(&pnn->pndevs.list));
+}
+
+static struct pernet_operations phonet_net_ops = {
+ .init = phonet_init_net,
+ .exit = phonet_exit_net,
+ .id = &phonet_net_id,
+ .size = sizeof(struct phonet_net),
+};
+
+/* Initialize Phonet devices list */
+int __init phonet_device_init(void)
+{
+ int err = register_pernet_subsys(&phonet_net_ops);
+ if (err)
+ return err;
+
+ proc_create_net("pnresource", 0, init_net.proc_net, &pn_res_seq_ops,
+ sizeof(struct seq_net_private));
+ register_netdevice_notifier(&phonet_device_notifier);
+ err = phonet_netlink_register();
+ if (err)
+ phonet_device_exit();
+ return err;
+}
+
+void phonet_device_exit(void)
+{
+ rtnl_unregister_all(PF_PHONET);
+ unregister_netdevice_notifier(&phonet_device_notifier);
+ unregister_pernet_subsys(&phonet_net_ops);
+ remove_proc_entry("pnresource", init_net.proc_net);
+}
+
+int phonet_route_add(struct net_device *dev, u8 daddr)
+{
+ struct phonet_net *pnn = phonet_pernet(dev_net(dev));
+ struct phonet_routes *routes = &pnn->routes;
+ int err = -EEXIST;
+
+ daddr = daddr >> 2;
+ mutex_lock(&routes->lock);
+ if (routes->table[daddr] == NULL) {
+ rcu_assign_pointer(routes->table[daddr], dev);
+ dev_hold(dev);
+ err = 0;
+ }
+ mutex_unlock(&routes->lock);
+ return err;
+}
+
+int phonet_route_del(struct net_device *dev, u8 daddr)
+{
+ struct phonet_net *pnn = phonet_pernet(dev_net(dev));
+ struct phonet_routes *routes = &pnn->routes;
+
+ daddr = daddr >> 2;
+ mutex_lock(&routes->lock);
+ if (rcu_access_pointer(routes->table[daddr]) == dev)
+ RCU_INIT_POINTER(routes->table[daddr], NULL);
+ else
+ dev = NULL;
+ mutex_unlock(&routes->lock);
+
+ if (!dev)
+ return -ENOENT;
+ synchronize_rcu();
+ dev_put(dev);
+ return 0;
+}
+
+struct net_device *phonet_route_get_rcu(struct net *net, u8 daddr)
+{
+ struct phonet_net *pnn = phonet_pernet(net);
+ struct phonet_routes *routes = &pnn->routes;
+ struct net_device *dev;
+
+ daddr >>= 2;
+ dev = rcu_dereference(routes->table[daddr]);
+ return dev;
+}
+
+struct net_device *phonet_route_output(struct net *net, u8 daddr)
+{
+ struct phonet_net *pnn = phonet_pernet(net);
+ struct phonet_routes *routes = &pnn->routes;
+ struct net_device *dev;
+
+ daddr >>= 2;
+ rcu_read_lock();
+ dev = rcu_dereference(routes->table[daddr]);
+ dev_hold(dev);
+ rcu_read_unlock();
+
+ if (!dev)
+ dev = phonet_device_get(net); /* Default route */
+ return dev;
+}