// SPDX-License-Identifier: GPL-2.0 /* Copyright (C) 2007-2018 B.A.T.M.A.N. contributors: * * Marek Lindner, Simon Wunderlich * * This program is free software; you can redistribute it and/or * modify it under the terms of version 2 of the GNU General Public * License as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, see <http://www.gnu.org/licenses/>. */ #include "main.h" #include <linux/atomic.h> #include <linux/build_bug.h> #include <linux/byteorder/generic.h> #include <linux/crc32c.h> #include <linux/errno.h> #include <linux/genetlink.h> #include <linux/gfp.h> #include <linux/if_ether.h> #include <linux/if_vlan.h> #include <linux/init.h> #include <linux/ip.h> #include <linux/ipv6.h> #include <linux/kernel.h> #include <linux/kref.h> #include <linux/list.h> #include <linux/module.h> #include <linux/netdevice.h> #include <linux/printk.h> #include <linux/rculist.h> #include <linux/rcupdate.h> #include <linux/seq_file.h> #include <linux/skbuff.h> #include <linux/spinlock.h> #include <linux/stddef.h> #include <linux/string.h> #include <linux/workqueue.h> #include <net/dsfield.h> #include <net/rtnetlink.h> #include <uapi/linux/batadv_packet.h> #include <uapi/linux/batman_adv.h> #include "bat_algo.h" #include "bat_iv_ogm.h" #include "bat_v.h" #include "bridge_loop_avoidance.h" #include "debugfs.h" #include "distributed-arp-table.h" #include "gateway_client.h" #include "gateway_common.h" #include "hard-interface.h" #include "icmp_socket.h" #include "log.h" #include "multicast.h" #include "netlink.h" #include "network-coding.h" #include "originator.h" #include "routing.h" #include "send.h" #include "soft-interface.h" #include "tp_meter.h" #include "translation-table.h" /* List manipulations on hardif_list have to be rtnl_lock()'ed, * list traversals just rcu-locked */ struct list_head batadv_hardif_list; static int (*batadv_rx_handler[256])(struct sk_buff *skb, struct batadv_hard_iface *recv_if); unsigned char batadv_broadcast_addr[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff}; struct workqueue_struct *batadv_event_workqueue; static void batadv_recv_handler_init(void); static int __init batadv_init(void) { int ret; ret = batadv_tt_cache_init(); if (ret < 0) return ret; INIT_LIST_HEAD(&batadv_hardif_list); batadv_algo_init(); batadv_recv_handler_init(); batadv_v_init(); batadv_iv_init(); batadv_nc_init(); batadv_tp_meter_init(); batadv_event_workqueue = create_singlethread_workqueue("bat_events"); if (!batadv_event_workqueue) goto err_create_wq; batadv_socket_init(); batadv_debugfs_init(); register_netdevice_notifier(&batadv_hard_if_notifier); rtnl_link_register(&batadv_link_ops); batadv_netlink_register(); pr_info("B.A.T.M.A.N. advanced %s (compatibility version %i) loaded\n", BATADV_SOURCE_VERSION, BATADV_COMPAT_VERSION); return 0; err_create_wq: batadv_tt_cache_destroy(); return -ENOMEM; } static void __exit batadv_exit(void) { batadv_debugfs_destroy(); batadv_netlink_unregister(); rtnl_link_unregister(&batadv_link_ops); unregister_netdevice_notifier(&batadv_hard_if_notifier); batadv_hardif_remove_interfaces(); flush_workqueue(batadv_event_workqueue); destroy_workqueue(batadv_event_workqueue); batadv_event_workqueue = NULL; rcu_barrier(); batadv_tt_cache_destroy(); } /** * batadv_mesh_init() - Initialize soft interface * @soft_iface: netdev struct of the soft interface * * Return: 0 on success or negative error number in case of failure */ int batadv_mesh_init(struct net_device *soft_iface) { struct batadv_priv *bat_priv = netdev_priv(soft_iface); int ret; spin_lock_init(&bat_priv->forw_bat_list_lock); spin_lock_init(&bat_priv->forw_bcast_list_lock); spin_lock_init(&bat_priv->tt.changes_list_lock); spin_lock_init(&bat_priv->tt.req_list_lock); spin_lock_init(&bat_priv->tt.roam_list_lock); spin_lock_init(&bat_priv->tt.last_changeset_lock); spin_lock_init(&bat_priv->tt.commit_lock); spin_lock_init(&bat_priv->gw.list_lock); #ifdef CONFIG_BATMAN_ADV_MCAST spin_lock_init(&bat_priv->mcast.want_lists_lock); #endif spin_lock_init(&bat_priv->tvlv.container_list_lock); spin_lock_init(&bat_priv->tvlv.handler_list_lock); spin_lock_init(&bat_priv->softif_vlan_list_lock); spin_lock_init(&bat_priv->tp_list_lock); INIT_HLIST_HEAD(&bat_priv->forw_bat_list); INIT_HLIST_HEAD(&bat_priv->forw_bcast_list); INIT_HLIST_HEAD(&bat_priv->gw.gateway_list); #ifdef CONFIG_BATMAN_ADV_MCAST INIT_HLIST_HEAD(&bat_priv->mcast.want_all_unsnoopables_list); INIT_HLIST_HEAD(&bat_priv->mcast.want_all_ipv4_list); INIT_HLIST_HEAD(&bat_priv->mcast.want_all_ipv6_list); #endif INIT_LIST_HEAD(&bat_priv->tt.changes_list); INIT_HLIST_HEAD(&bat_priv->tt.req_list); INIT_LIST_HEAD(&bat_priv->tt.roam_list); #ifdef CONFIG_BATMAN_ADV_MCAST INIT_HLIST_HEAD(&bat_priv->mcast.mla_list); #endif INIT_HLIST_HEAD(&bat_priv->tvlv.container_list); INIT_HLIST_HEAD(&bat_priv->tvlv.handler_list); INIT_HLIST_HEAD(&bat_priv->softif_vlan_list); INIT_HLIST_HEAD(&bat_priv->tp_list); ret = batadv_v_mesh_init(bat_priv); if (ret < 0) goto err; ret = batadv_originator_init(bat_priv); if (ret < 0) goto err; ret = batadv_tt_init(bat_priv); if (ret < 0) goto err; ret = batadv_bla_init(bat_priv); if (ret < 0) goto err; ret = batadv_dat_init(bat_priv); if (ret < 0) goto err; ret = batadv_nc_mesh_init(bat_priv); if (ret < 0) goto err; batadv_gw_init(bat_priv); batadv_mcast_init(bat_priv); atomic_set(&bat_priv->gw.reselect, 0); atomic_set(&bat_priv->mesh_state, BATADV_MESH_ACTIVE); return 0; err: batadv_mesh_free(soft_iface); return ret; } /** * batadv_mesh_free() - Deinitialize soft interface * @soft_iface: netdev struct of the soft interface */ void batadv_mesh_free(struct net_device *soft_iface) { struct batadv_priv *bat_priv = netdev_priv(soft_iface); atomic_set(&bat_priv->mesh_state, BATADV_MESH_DEACTIVATING); batadv_purge_outstanding_packets(bat_priv, NULL); batadv_gw_node_free(bat_priv); batadv_v_mesh_free(bat_priv); batadv_nc_mesh_free(bat_priv); batadv_dat_free(bat_priv); batadv_bla_free(bat_priv); batadv_mcast_free(bat_priv); /* Free the TT and the originator tables only after having terminated * all the other depending components which may use these structures for * their purposes. */ batadv_tt_free(bat_priv); /* Since the originator table clean up routine is accessing the TT * tables as well, it has to be invoked after the TT tables have been * freed and marked as empty. This ensures that no cleanup RCU callbacks * accessing the TT data are scheduled for later execution. */ batadv_originator_free(bat_priv); batadv_gw_free(bat_priv); free_percpu(bat_priv->bat_counters); bat_priv->bat_counters = NULL; atomic_set(&bat_priv->mesh_state, BATADV_MESH_INACTIVE); } /** * batadv_is_my_mac() - check if the given mac address belongs to any of the * real interfaces in the current mesh * @bat_priv: the bat priv with all the soft interface information * @addr: the address to check * * Return: 'true' if the mac address was found, false otherwise. */ bool batadv_is_my_mac(struct batadv_priv *bat_priv, const u8 *addr) { const struct batadv_hard_iface *hard_iface; bool is_my_mac = false; rcu_read_lock(); list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) { if (hard_iface->if_status != BATADV_IF_ACTIVE) continue; if (hard_iface->soft_iface != bat_priv->soft_iface) continue; if (batadv_compare_eth(hard_iface->net_dev->dev_addr, addr)) { is_my_mac = true; break; } } rcu_read_unlock(); return is_my_mac; } #ifdef CONFIG_BATMAN_ADV_DEBUGFS /** * batadv_seq_print_text_primary_if_get() - called from debugfs table printing * function that requires the primary interface * @seq: debugfs table seq_file struct * * Return: primary interface if found or NULL otherwise. */ struct batadv_hard_iface * batadv_seq_print_text_primary_if_get(struct seq_file *seq) { struct net_device *net_dev = (struct net_device *)seq->private; struct batadv_priv *bat_priv = netdev_priv(net_dev); struct batadv_hard_iface *primary_if; primary_if = batadv_primary_if_get_selected(bat_priv); if (!primary_if) { seq_printf(seq, "BATMAN mesh %s disabled - please specify interfaces to enable it\n", net_dev->name); goto out; } if (primary_if->if_status == BATADV_IF_ACTIVE) goto out; seq_printf(seq, "BATMAN mesh %s disabled - primary interface not active\n", net_dev->name); batadv_hardif_put(primary_if); primary_if = NULL; out: return primary_if; } #endif /** * batadv_max_header_len() - calculate maximum encapsulation overhead for a * payload packet * * Return: the maximum encapsulation overhead in bytes. */ int batadv_max_header_len(void) { int header_len = 0; header_len = max_t(int, header_len, sizeof(struct batadv_unicast_packet)); header_len = max_t(int, header_len, sizeof(struct batadv_unicast_4addr_packet)); header_len = max_t(int, header_len, sizeof(struct batadv_bcast_packet)); #ifdef CONFIG_BATMAN_ADV_NC header_len = max_t(int, header_len, sizeof(struct batadv_coded_packet)); #endif return header_len + ETH_HLEN; } /** * batadv_skb_set_priority() - sets skb priority according to packet content * @skb: the packet to be sent * @offset: offset to the packet content * * This function sets a value between 256 and 263 (802.1d priority), which * can be interpreted by the cfg80211 or other drivers. */ void batadv_skb_set_priority(struct sk_buff *skb, int offset) { struct iphdr ip_hdr_tmp, *ip_hdr; struct ipv6hdr ip6_hdr_tmp, *ip6_hdr; struct ethhdr ethhdr_tmp, *ethhdr; struct vlan_ethhdr *vhdr, vhdr_tmp; u32 prio; /* already set, do nothing */ if (skb->priority >= 256 && skb->priority <= 263) return; ethhdr = skb_header_pointer(skb, offset, sizeof(*ethhdr), ðhdr_tmp); if (!ethhdr) return; switch (ethhdr->h_proto) { case htons(ETH_P_8021Q): vhdr = skb_header_pointer(skb, offset + sizeof(*vhdr), sizeof(*vhdr), &vhdr_tmp); if (!vhdr) return; prio = ntohs(vhdr->h_vlan_TCI) & VLAN_PRIO_MASK; prio = prio >> VLAN_PRIO_SHIFT; break; case htons(ETH_P_IP): ip_hdr = skb_header_pointer(skb, offset + sizeof(*ethhdr), sizeof(*ip_hdr), &ip_hdr_tmp); if (!ip_hdr) return; prio = (ipv4_get_dsfield(ip_hdr) & 0xfc) >> 5; break; case htons(ETH_P_IPV6): ip6_hdr = skb_header_pointer(skb, offset + sizeof(*ethhdr), sizeof(*ip6_hdr), &ip6_hdr_tmp); if (!ip6_hdr) return; prio = (ipv6_get_dsfield(ip6_hdr) & 0xfc) >> 5; break; default: return; } skb->priority = prio + 256; } static int batadv_recv_unhandled_packet(struct sk_buff *skb, struct batadv_hard_iface *recv_if) { kfree_skb(skb); return NET_RX_DROP; } /* incoming packets with the batman ethertype received on any active hard * interface */ /** * batadv_batman_skb_recv() - Handle incoming message from an hard interface * @skb: the received packet * @dev: the net device that the packet was received on * @ptype: packet type of incoming packet (ETH_P_BATMAN) * @orig_dev: the original receive net device (e.g. bonded device) * * Return: NET_RX_SUCCESS on success or NET_RX_DROP in case of failure */ int batadv_batman_skb_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *ptype, struct net_device *orig_dev) { struct batadv_priv *bat_priv; struct batadv_ogm_packet *batadv_ogm_packet; struct batadv_hard_iface *hard_iface; u8 idx; hard_iface = container_of(ptype, struct batadv_hard_iface, batman_adv_ptype); /* Prevent processing a packet received on an interface which is getting * shut down otherwise the packet may trigger de-reference errors * further down in the receive path. */ if (!kref_get_unless_zero(&hard_iface->refcount)) goto err_out; skb = skb_share_check(skb, GFP_ATOMIC); /* skb was released by skb_share_check() */ if (!skb) goto err_put; /* packet should hold at least type and version */ if (unlikely(!pskb_may_pull(skb, 2))) goto err_free; /* expect a valid ethernet header here. */ if (unlikely(skb->mac_len != ETH_HLEN || !skb_mac_header(skb))) goto err_free; if (!hard_iface->soft_iface) goto err_free; bat_priv = netdev_priv(hard_iface->soft_iface); if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE) goto err_free; /* discard frames on not active interfaces */ if (hard_iface->if_status != BATADV_IF_ACTIVE) goto err_free; batadv_ogm_packet = (struct batadv_ogm_packet *)skb->data; if (batadv_ogm_packet->version != BATADV_COMPAT_VERSION) { batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "Drop packet: incompatible batman version (%i)\n", batadv_ogm_packet->version); goto err_free; } /* reset control block to avoid left overs from previous users */ memset(skb->cb, 0, sizeof(struct batadv_skb_cb)); idx = batadv_ogm_packet->packet_type; (*batadv_rx_handler[idx])(skb, hard_iface); batadv_hardif_put(hard_iface); /* return NET_RX_SUCCESS in any case as we * most probably dropped the packet for * routing-logical reasons. */ return NET_RX_SUCCESS; err_free: kfree_skb(skb); err_put: batadv_hardif_put(hard_iface); err_out: return NET_RX_DROP; } static void batadv_recv_handler_init(void) { int i; for (i = 0; i < ARRAY_SIZE(batadv_rx_handler); i++) batadv_rx_handler[i] = batadv_recv_unhandled_packet; for (i = BATADV_UNICAST_MIN; i <= BATADV_UNICAST_MAX; i++) batadv_rx_handler[i] = batadv_recv_unhandled_unicast_packet; /* compile time checks for sizes */ BUILD_BUG_ON(sizeof(struct batadv_bla_claim_dst) != 6); BUILD_BUG_ON(sizeof(struct batadv_ogm_packet) != 24); BUILD_BUG_ON(sizeof(struct batadv_icmp_header) != 20); BUILD_BUG_ON(sizeof(struct batadv_icmp_packet) != 20); BUILD_BUG_ON(sizeof(struct batadv_icmp_packet_rr) != 116); BUILD_BUG_ON(sizeof(struct batadv_unicast_packet) != 10); BUILD_BUG_ON(sizeof(struct batadv_unicast_4addr_packet) != 18); BUILD_BUG_ON(sizeof(struct batadv_frag_packet) != 20); BUILD_BUG_ON(sizeof(struct batadv_bcast_packet) != 14); BUILD_BUG_ON(sizeof(struct batadv_coded_packet) != 46); BUILD_BUG_ON(sizeof(struct batadv_unicast_tvlv_packet) != 20); BUILD_BUG_ON(sizeof(struct batadv_tvlv_hdr) != 4); BUILD_BUG_ON(sizeof(struct batadv_tvlv_gateway_data) != 8); BUILD_BUG_ON(sizeof(struct batadv_tvlv_tt_vlan_data) != 8); BUILD_BUG_ON(sizeof(struct batadv_tvlv_tt_change) != 12); BUILD_BUG_ON(sizeof(struct batadv_tvlv_roam_adv) != 8); i = FIELD_SIZEOF(struct sk_buff, cb); BUILD_BUG_ON(sizeof(struct batadv_skb_cb) > i); /* broadcast packet */ batadv_rx_handler[BATADV_BCAST] = batadv_recv_bcast_packet; /* unicast packets ... */ /* unicast with 4 addresses packet */ batadv_rx_handler[BATADV_UNICAST_4ADDR] = batadv_recv_unicast_packet; /* unicast packet */ batadv_rx_handler[BATADV_UNICAST] = batadv_recv_unicast_packet; /* unicast tvlv packet */ batadv_rx_handler[BATADV_UNICAST_TVLV] = batadv_recv_unicast_tvlv; /* batman icmp packet */ batadv_rx_handler[BATADV_ICMP] = batadv_recv_icmp_packet; /* Fragmented packets */ batadv_rx_handler[BATADV_UNICAST_FRAG] = batadv_recv_frag_packet; } /** * batadv_recv_handler_register() - Register handler for batman-adv packet type * @packet_type: batadv_packettype which should be handled * @recv_handler: receive handler for the packet type * * Return: 0 on success or negative error number in case of failure */ int batadv_recv_handler_register(u8 packet_type, int (*recv_handler)(struct sk_buff *, struct batadv_hard_iface *)) { int (*curr)(struct sk_buff *skb, struct batadv_hard_iface *recv_if); curr = batadv_rx_handler[packet_type]; if (curr != batadv_recv_unhandled_packet && curr != batadv_recv_unhandled_unicast_packet) return -EBUSY; batadv_rx_handler[packet_type] = recv_handler; return 0; } /** * batadv_recv_handler_unregister() - Unregister handler for packet type * @packet_type: batadv_packettype which should no longer be handled */ void batadv_recv_handler_unregister(u8 packet_type) { batadv_rx_handler[packet_type] = batadv_recv_unhandled_packet; } /** * batadv_skb_crc32() - calculate CRC32 of the whole packet and skip bytes in * the header * @skb: skb pointing to fragmented socket buffers * @payload_ptr: Pointer to position inside the head buffer of the skb * marking the start of the data to be CRC'ed * * payload_ptr must always point to an address in the skb head buffer and not to * a fragment. * * Return: big endian crc32c of the checksummed data */ __be32 batadv_skb_crc32(struct sk_buff *skb, u8 *payload_ptr) { u32 crc = 0; unsigned int from; unsigned int to = skb->len; struct skb_seq_state st; const u8 *data; unsigned int len; unsigned int consumed = 0; from = (unsigned int)(payload_ptr - skb->data); skb_prepare_seq_read(skb, from, to, &st); while ((len = skb_seq_read(consumed, &data, &st)) != 0) { crc = crc32c(crc, data, len); consumed += len; } return htonl(crc); } /** * batadv_get_vid() - extract the VLAN identifier from skb if any * @skb: the buffer containing the packet * @header_len: length of the batman header preceding the ethernet header * * Return: VID with the BATADV_VLAN_HAS_TAG flag when the packet embedded in the * skb is vlan tagged. Otherwise BATADV_NO_FLAGS. */ unsigned short batadv_get_vid(struct sk_buff *skb, size_t header_len) { struct ethhdr *ethhdr = (struct ethhdr *)(skb->data + header_len); struct vlan_ethhdr *vhdr; unsigned short vid; if (ethhdr->h_proto != htons(ETH_P_8021Q)) return BATADV_NO_FLAGS; if (!pskb_may_pull(skb, header_len + VLAN_ETH_HLEN)) return BATADV_NO_FLAGS; vhdr = (struct vlan_ethhdr *)(skb->data + header_len); vid = ntohs(vhdr->h_vlan_TCI) & VLAN_VID_MASK; vid |= BATADV_VLAN_HAS_TAG; return vid; } /** * batadv_vlan_ap_isola_get() - return AP isolation status for the given vlan * @bat_priv: the bat priv with all the soft interface information * @vid: the VLAN identifier for which the AP isolation attributed as to be * looked up * * Return: true if AP isolation is on for the VLAN idenfied by vid, false * otherwise */ bool batadv_vlan_ap_isola_get(struct batadv_priv *bat_priv, unsigned short vid) { bool ap_isolation_enabled = false; struct batadv_softif_vlan *vlan; /* if the AP isolation is requested on a VLAN, then check for its * setting in the proper VLAN private data structure */ vlan = batadv_softif_vlan_get(bat_priv, vid); if (vlan) { ap_isolation_enabled = atomic_read(&vlan->ap_isolation); batadv_softif_vlan_put(vlan); } return ap_isolation_enabled; } module_init(batadv_init); module_exit(batadv_exit); MODULE_LICENSE("GPL"); MODULE_AUTHOR(BATADV_DRIVER_AUTHOR); MODULE_DESCRIPTION(BATADV_DRIVER_DESC); MODULE_SUPPORTED_DEVICE(BATADV_DRIVER_DEVICE); MODULE_VERSION(BATADV_SOURCE_VERSION); MODULE_ALIAS_RTNL_LINK("batadv"); MODULE_ALIAS_GENL_FAMILY(BATADV_NL_NAME);