/* * net/tipc/eth_media.c: Ethernet bearer support for TIPC * * Copyright (c) 2001-2007, Ericsson AB * Copyright (c) 2005-2007, Wind River Systems * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the names of the copyright holders nor the names of its * contributors may be used to endorse or promote products derived from * this software without specific prior written permission. * * Alternatively, this software may be distributed under the terms of the * GNU General Public License ("GPL") version 2 as published by the Free * Software Foundation. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ #include <net/tipc/tipc.h> #include <net/tipc/tipc_bearer.h> #include <net/tipc/tipc_msg.h> #include <linux/netdevice.h> #include <net/net_namespace.h> #define MAX_ETH_BEARERS 2 #define ETH_LINK_PRIORITY TIPC_DEF_LINK_PRI #define ETH_LINK_TOLERANCE TIPC_DEF_LINK_TOL #define ETH_LINK_WINDOW TIPC_DEF_LINK_WIN /** * struct eth_bearer - Ethernet bearer data structure * @bearer: ptr to associated "generic" bearer structure * @dev: ptr to associated Ethernet network device * @tipc_packet_type: used in binding TIPC to Ethernet driver */ struct eth_bearer { struct tipc_bearer *bearer; struct net_device *dev; struct packet_type tipc_packet_type; }; static struct eth_bearer eth_bearers[MAX_ETH_BEARERS]; static int eth_started = 0; static struct notifier_block notifier; /** * send_msg - send a TIPC message out over an Ethernet interface */ static int send_msg(struct sk_buff *buf, struct tipc_bearer *tb_ptr, struct tipc_media_addr *dest) { struct sk_buff *clone; struct net_device *dev; clone = skb_clone(buf, GFP_ATOMIC); if (clone) { skb_reset_network_header(clone); dev = ((struct eth_bearer *)(tb_ptr->usr_handle))->dev; clone->dev = dev; dev_hard_header(clone, dev, ETH_P_TIPC, &dest->dev_addr.eth_addr, dev->dev_addr, clone->len); dev_queue_xmit(clone); } return 0; } /** * recv_msg - handle incoming TIPC message from an Ethernet interface * * Accept only packets explicitly sent to this node, or broadcast packets; * ignores packets sent using Ethernet multicast, and traffic sent to other * nodes (which can happen if interface is running in promiscuous mode). * Routine truncates any Ethernet padding/CRC appended to the message, * and ensures message size matches actual length */ static int recv_msg(struct sk_buff *buf, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev) { struct eth_bearer *eb_ptr = (struct eth_bearer *)pt->af_packet_priv; u32 size; if (!net_eq(dev_net(dev), &init_net)) { kfree_skb(buf); return 0; } if (likely(eb_ptr->bearer)) { if (likely(buf->pkt_type <= PACKET_BROADCAST)) { size = msg_size((struct tipc_msg *)buf->data); skb_trim(buf, size); if (likely(buf->len == size)) { buf->next = NULL; tipc_recv_msg(buf, eb_ptr->bearer); return 0; } } } kfree_skb(buf); return 0; } /** * enable_bearer - attach TIPC bearer to an Ethernet interface */ static int enable_bearer(struct tipc_bearer *tb_ptr) { struct net_device *dev = NULL; struct net_device *pdev = NULL; struct eth_bearer *eb_ptr = ð_bearers[0]; struct eth_bearer *stop = ð_bearers[MAX_ETH_BEARERS]; char *driver_name = strchr((const char *)tb_ptr->name, ':') + 1; /* Find device with specified name */ for_each_netdev(&init_net, pdev){ if (!strncmp(pdev->name, driver_name, IFNAMSIZ)) { dev = pdev; break; } } if (!dev) return -ENODEV; /* Find Ethernet bearer for device (or create one) */ for (;(eb_ptr != stop) && eb_ptr->dev && (eb_ptr->dev != dev); eb_ptr++); if (eb_ptr == stop) return -EDQUOT; if (!eb_ptr->dev) { eb_ptr->dev = dev; eb_ptr->tipc_packet_type.type = htons(ETH_P_TIPC); eb_ptr->tipc_packet_type.dev = dev; eb_ptr->tipc_packet_type.func = recv_msg; eb_ptr->tipc_packet_type.af_packet_priv = eb_ptr; INIT_LIST_HEAD(&(eb_ptr->tipc_packet_type.list)); dev_hold(dev); dev_add_pack(&eb_ptr->tipc_packet_type); } /* Associate TIPC bearer with Ethernet bearer */ eb_ptr->bearer = tb_ptr; tb_ptr->usr_handle = (void *)eb_ptr; tb_ptr->mtu = dev->mtu; tb_ptr->blocked = 0; tb_ptr->addr.type = htonl(TIPC_MEDIA_TYPE_ETH); memcpy(&tb_ptr->addr.dev_addr, dev->dev_addr, ETH_ALEN); return 0; } /** * disable_bearer - detach TIPC bearer from an Ethernet interface * * We really should do dev_remove_pack() here, but this function can not be * called at tasklet level. => Use eth_bearer->bearer as a flag to throw away * incoming buffers, & postpone dev_remove_pack() to eth_media_stop() on exit. */ static void disable_bearer(struct tipc_bearer *tb_ptr) { ((struct eth_bearer *)tb_ptr->usr_handle)->bearer = NULL; } /** * recv_notification - handle device updates from OS * * Change the state of the Ethernet bearer (if any) associated with the * specified device. */ static int recv_notification(struct notifier_block *nb, unsigned long evt, void *dv) { struct net_device *dev = (struct net_device *)dv; struct eth_bearer *eb_ptr = ð_bearers[0]; struct eth_bearer *stop = ð_bearers[MAX_ETH_BEARERS]; if (!net_eq(dev_net(dev), &init_net)) return NOTIFY_DONE; while ((eb_ptr->dev != dev)) { if (++eb_ptr == stop) return NOTIFY_DONE; /* couldn't find device */ } if (!eb_ptr->bearer) return NOTIFY_DONE; /* bearer had been disabled */ eb_ptr->bearer->mtu = dev->mtu; switch (evt) { case NETDEV_CHANGE: if (netif_carrier_ok(dev)) tipc_continue(eb_ptr->bearer); else tipc_block_bearer(eb_ptr->bearer->name); break; case NETDEV_UP: tipc_continue(eb_ptr->bearer); break; case NETDEV_DOWN: tipc_block_bearer(eb_ptr->bearer->name); break; case NETDEV_CHANGEMTU: case NETDEV_CHANGEADDR: tipc_block_bearer(eb_ptr->bearer->name); tipc_continue(eb_ptr->bearer); break; case NETDEV_UNREGISTER: case NETDEV_CHANGENAME: tipc_disable_bearer(eb_ptr->bearer->name); break; } return NOTIFY_OK; } /** * eth_addr2str - convert Ethernet address to string */ static char *eth_addr2str(struct tipc_media_addr *a, char *str_buf, int str_size) { unchar *addr = (unchar *)&a->dev_addr; if (str_size < 18) *str_buf = '\0'; else sprintf(str_buf, "%pM", addr); return str_buf; } /** * tipc_eth_media_start - activate Ethernet bearer support * * Register Ethernet media type with TIPC bearer code. Also register * with OS for notifications about device state changes. */ int tipc_eth_media_start(void) { struct tipc_media_addr bcast_addr; int res; if (eth_started) return -EINVAL; bcast_addr.type = htonl(TIPC_MEDIA_TYPE_ETH); memset(&bcast_addr.dev_addr, 0xff, ETH_ALEN); memset(eth_bearers, 0, sizeof(eth_bearers)); res = tipc_register_media(TIPC_MEDIA_TYPE_ETH, "eth", enable_bearer, disable_bearer, send_msg, eth_addr2str, &bcast_addr, ETH_LINK_PRIORITY, ETH_LINK_TOLERANCE, ETH_LINK_WINDOW); if (res) return res; notifier.notifier_call = &recv_notification; notifier.priority = 0; res = register_netdevice_notifier(¬ifier); if (!res) eth_started = 1; return res; } /** * tipc_eth_media_stop - deactivate Ethernet bearer support */ void tipc_eth_media_stop(void) { int i; if (!eth_started) return; unregister_netdevice_notifier(¬ifier); for (i = 0; i < MAX_ETH_BEARERS ; i++) { if (eth_bearers[i].bearer) { eth_bearers[i].bearer->blocked = 1; eth_bearers[i].bearer = NULL; } if (eth_bearers[i].dev) { dev_remove_pack(ð_bearers[i].tipc_packet_type); dev_put(eth_bearers[i].dev); } } memset(ð_bearers, 0, sizeof(eth_bearers)); eth_started = 0; }