1 // SPDX-License-Identifier: GPL-2.0
7 #include "distributed-arp-table.h"
43 #include "hard-interface.h"
49 #include "soft-interface.h"
50 #include "translation-table.h"
93 #define BATADV_DHCP_YIADDR_LEN sizeof(((struct batadv_dhcp_packet *)0)->yiaddr)
94 #define BATADV_DHCP_CHADDR_LEN sizeof(((struct batadv_dhcp_packet *)0)->chaddr)
99  * batadv_dat_start_timer() - initialise the DAT periodic worker
104 	INIT_DELAYED_WORK(&bat_priv->dat.work, batadv_dat_purge);  in batadv_dat_start_timer()
105 	queue_delayed_work(batadv_event_workqueue, &bat_priv->dat.work,  in batadv_dat_start_timer()
110  * batadv_dat_entry_release() - release dat_entry from lists and queue for free
124  * batadv_dat_entry_put() - decrement the dat_entry refcounter and possibly
133 	kref_put(&dat_entry->refcount, batadv_dat_entry_release);  in batadv_dat_entry_put()
137  * batadv_dat_to_purge() - check whether a dat_entry has to be purged or not
144 	return batadv_has_timed_out(dat_entry->last_update,  in batadv_dat_to_purge()
149  * __batadv_dat_purge() - delete entries from the DAT local storage
168 	if (!bat_priv->dat.hash)  in __batadv_dat_purge()
171 	for (i = 0; i < bat_priv->dat.hash->size; i++) {  in __batadv_dat_purge()
172 		head = &bat_priv->dat.hash->table[i];  in __batadv_dat_purge()
173 		list_lock = &bat_priv->dat.hash->list_locks[i];  in __batadv_dat_purge()
184 			hlist_del_rcu(&dat_entry->hash_entry);  in __batadv_dat_purge()
192  * batadv_dat_purge() - periodic task that deletes old entries from the local
211  * batadv_compare_dat() - comparing function used in the local DAT hash table
226  * batadv_arp_hw_src() - extract the hw_src field from an ARP packet
236 	addr = (u8 *)(skb->data + hdr_size);  in batadv_arp_hw_src()
243  * batadv_arp_ip_src() - extract the ip_src field from an ARP packet
255  * batadv_arp_hw_dst() - extract the hw_dst field from an ARP packet
267  * batadv_arp_ip_dst() - extract the ip_dst field from an ARP packet
281  * batadv_hash_dat() - compute the hash value for an IP address
295 	key = (__force const unsigned char *)&dat->ip;  in batadv_hash_dat()
296 	for (i = 0; i < sizeof(dat->ip); i++) {  in batadv_hash_dat()
302 	vid = htons(dat->vid);  in batadv_hash_dat()
304 	for (i = 0; i < sizeof(dat->vid); i++) {  in batadv_hash_dat()
318  * batadv_dat_entry_hash_find() - look for a given dat_entry in the local hash
332 	struct batadv_hashtable *hash = bat_priv->dat.hash;  in batadv_dat_entry_hash_find()
341 	index = batadv_hash_dat(&to_find, hash->size);  in batadv_dat_entry_hash_find()
342 	head = &hash->table[index];  in batadv_dat_entry_hash_find()
346 		if (dat_entry->ip != ip)  in batadv_dat_entry_hash_find()
349 		if (!kref_get_unless_zero(&dat_entry->refcount))  in batadv_dat_entry_hash_find()
361  * batadv_dat_entry_add() - add a new dat entry or update it if already exists
376 		if (!batadv_compare_eth(dat_entry->mac_addr, mac_addr))  in batadv_dat_entry_add()
377 			ether_addr_copy(dat_entry->mac_addr, mac_addr);  in batadv_dat_entry_add()
378 		dat_entry->last_update = jiffies;  in batadv_dat_entry_add()
381 			   &dat_entry->ip, dat_entry->mac_addr,  in batadv_dat_entry_add()
390 	dat_entry->ip = ip;  in batadv_dat_entry_add()
391 	dat_entry->vid = vid;  in batadv_dat_entry_add()
392 	ether_addr_copy(dat_entry->mac_addr, mac_addr);  in batadv_dat_entry_add()
393 	dat_entry->last_update = jiffies;  in batadv_dat_entry_add()
394 	kref_init(&dat_entry->refcount);  in batadv_dat_entry_add()
396 	kref_get(&dat_entry->refcount);  in batadv_dat_entry_add()
397 	hash_added = batadv_hash_add(bat_priv->dat.hash, batadv_compare_dat,  in batadv_dat_entry_add()
399 				     &dat_entry->hash_entry);  in batadv_dat_entry_add()
408 		   &dat_entry->ip, dat_entry->mac_addr, batadv_print_vid(vid));  in batadv_dat_entry_add()
417  * batadv_dbg_arp() - print a debug message containing all the ARP packet
438 		   "ARP MSG = [src: %pM-%pI4 dst: %pM-%pI4]\n",  in batadv_dbg_arp()
445 	unicast_4addr_packet = (struct batadv_unicast_4addr_packet *)skb->data;  in batadv_dbg_arp()
447 	switch (unicast_4addr_packet->u.packet_type) {  in batadv_dbg_arp()
455 			   unicast_4addr_packet->src);  in batadv_dbg_arp()
456 		switch (unicast_4addr_packet->subtype) {  in batadv_dbg_arp()
472 				   unicast_4addr_packet->u.packet_type);  in batadv_dbg_arp()
477 		orig_addr = bcast_pkt->orig;  in batadv_dbg_arp()
485 			   unicast_4addr_packet->u.packet_type);  in batadv_dbg_arp()
499  * batadv_is_orig_node_eligible() - check whether a node can be a DHT candidate
522 	if (!test_bit(BATADV_ORIG_CAPA_HAS_DAT, &candidate->capabilities))  in batadv_is_orig_node_eligible()
544 	    batadv_compare_eth(candidate->orig, max_orig_node->orig))  in batadv_is_orig_node_eligible()
553  * batadv_choose_next_candidate() - select the next DHT candidate
557  * @ip_key: key to look up in the DHT
568 	struct batadv_hashtable *hash = bat_priv->orig_hash;  in batadv_choose_next_candidate()
580 	for (i = 0; i < hash->size; i++) {  in batadv_choose_next_candidate()
581 		head = &hash->table[i];  in batadv_choose_next_candidate()
586 			tmp_max = BATADV_DAT_ADDR_MAX - orig_node->dat_addr +  in batadv_choose_next_candidate()
595 			if (!kref_get_unless_zero(&orig_node->refcount))  in batadv_choose_next_candidate()
609 			   select, max_orig_node->orig, max_orig_node->dat_addr,  in batadv_choose_next_candidate()
616  * batadv_dat_select_candidates() - select the nodes which the DHT message has
619  * @ip_dst: ipv4 to look up in the DHT
637 	if (!bat_priv->orig_hash)  in batadv_dat_select_candidates()
662  * batadv_dat_forward_data() - copy and send payload to the selected candidates
738  * batadv_dat_tvlv_container_update() - update the dat tvlv container after dat
746 	dat_mode = atomic_read(&bat_priv->distributed_arp_table);  in batadv_dat_tvlv_container_update()
760  * batadv_dat_status_update() - update the dat tvlv container after dat
772  * batadv_dat_tvlv_ogm_handler_v1() - process incoming dat tvlv container
785 		clear_bit(BATADV_ORIG_CAPA_HAS_DAT, &orig->capabilities);  in batadv_dat_tvlv_ogm_handler_v1()
787 		set_bit(BATADV_ORIG_CAPA_HAS_DAT, &orig->capabilities);  in batadv_dat_tvlv_ogm_handler_v1()
791  * batadv_dat_hash_free() - free the local DAT hash table
796 	if (!bat_priv->dat.hash)  in batadv_dat_hash_free()
801 	batadv_hash_destroy(bat_priv->dat.hash);  in batadv_dat_hash_free()
803 	bat_priv->dat.hash = NULL;  in batadv_dat_hash_free()
807  * batadv_dat_init() - initialise the DAT internals
814 	if (bat_priv->dat.hash)  in batadv_dat_init()
817 	bat_priv->dat.hash = batadv_hash_new(1024);  in batadv_dat_init()
819 	if (!bat_priv->dat.hash)  in batadv_dat_init()
820 		return -ENOMEM;  in batadv_dat_init()
832  * batadv_dat_free() - free the DAT internals
840 	cancel_delayed_work_sync(&bat_priv->dat.work);  in batadv_dat_free()
846  * batadv_dat_cache_dump_entry() - dump one entry of the DAT cache table to a
863 	hdr = genlmsg_put(msg, portid, cb->nlh->nlmsg_seq,  in batadv_dat_cache_dump_entry()
867 		return -ENOBUFS;  in batadv_dat_cache_dump_entry()
871 	msecs = jiffies_to_msecs(jiffies - dat_entry->last_update);  in batadv_dat_cache_dump_entry()
874 			    dat_entry->ip) ||  in batadv_dat_cache_dump_entry()
876 		    dat_entry->mac_addr) ||  in batadv_dat_cache_dump_entry()
877 	    nla_put_u16(msg, BATADV_ATTR_DAT_CACHE_VID, dat_entry->vid) ||  in batadv_dat_cache_dump_entry()
880 		return -EMSGSIZE;  in batadv_dat_cache_dump_entry()
888  * batadv_dat_cache_dump_bucket() - dump one bucket of the DAT cache table to
908 	spin_lock_bh(&hash->list_locks[bucket]);  in batadv_dat_cache_dump_bucket()
909 	cb->seq = atomic_read(&hash->generation) << 1 | 1;  in batadv_dat_cache_dump_bucket()
911 	hlist_for_each_entry(dat_entry, &hash->table[bucket], hash_entry) {  in batadv_dat_cache_dump_bucket()
916 			spin_unlock_bh(&hash->list_locks[bucket]);  in batadv_dat_cache_dump_bucket()
919 			return -EMSGSIZE;  in batadv_dat_cache_dump_bucket()
925 	spin_unlock_bh(&hash->list_locks[bucket]);  in batadv_dat_cache_dump_bucket()
931  * batadv_dat_cache_dump() - dump DAT cache table to a netlink socket
940 	int portid = NETLINK_CB(cb->skb).portid;  in batadv_dat_cache_dump()
941 	struct net *net = sock_net(cb->skb->sk);  in batadv_dat_cache_dump()
945 	int bucket = cb->args[0];  in batadv_dat_cache_dump()
946 	int idx = cb->args[1];  in batadv_dat_cache_dump()
950 	ifindex = batadv_netlink_get_ifindex(cb->nlh,  in batadv_dat_cache_dump()
953 		return -EINVAL;  in batadv_dat_cache_dump()
957 		ret = -ENODEV;  in batadv_dat_cache_dump()
962 	hash = bat_priv->dat.hash;  in batadv_dat_cache_dump()
965 	if (!primary_if || primary_if->if_status != BATADV_IF_ACTIVE) {  in batadv_dat_cache_dump()
966 		ret = -ENOENT;  in batadv_dat_cache_dump()
970 	while (bucket < hash->size) {  in batadv_dat_cache_dump()
979 	cb->args[0] = bucket;  in batadv_dat_cache_dump()
980 	cb->args[1] = idx;  in batadv_dat_cache_dump()
982 	ret = msg->len;  in batadv_dat_cache_dump()
993  * batadv_arp_get_type() - parse an ARP packet and gets the type
1009 	/* pull the ethernet header */  in batadv_arp_get_type()
1013 	ethhdr = (struct ethhdr *)(skb->data + hdr_size);  in batadv_arp_get_type()
1015 	if (ethhdr->h_proto != htons(ETH_P_ARP))  in batadv_arp_get_type()
1018 	/* pull the ARP payload */  in batadv_arp_get_type()
1020 				    arp_hdr_len(skb->dev))))  in batadv_arp_get_type()
1023 	arphdr = (struct arphdr *)(skb->data + hdr_size + ETH_HLEN);  in batadv_arp_get_type()
1026 	if (arphdr->ar_hrd != htons(ARPHRD_ETHER))  in batadv_arp_get_type()
1029 	if (arphdr->ar_pro != htons(ETH_P_IP))  in batadv_arp_get_type()
1032 	if (arphdr->ar_hln != ETH_ALEN)  in batadv_arp_get_type()
1035 	if (arphdr->ar_pln != 4)  in batadv_arp_get_type()
1054 	if (arphdr->ar_op != htons(ARPOP_REQUEST)) {  in batadv_arp_get_type()
1061 	type = ntohs(arphdr->ar_op);  in batadv_arp_get_type()
1067  * batadv_dat_get_vid() - extract the VLAN identifier from skb if any
1069  * @hdr_size: the size of the batman-adv header encapsulating the packet
1093  * batadv_dat_arp_create_reply() - create an ARP Reply
1113 	skb = arp_create(ARPOP_REPLY, ETH_P_ARP, ip_dst, bat_priv->soft_iface,  in batadv_dat_arp_create_reply()
1128  * batadv_dat_snoop_outgoing_arp_request() - snoop the ARP request and try to
1146 	struct net_device *soft_iface = bat_priv->soft_iface;  in batadv_dat_snoop_outgoing_arp_request()
1150 	if (!atomic_read(&bat_priv->distributed_arp_table))  in batadv_dat_snoop_outgoing_arp_request()
1176 		 * Moreover, if the soft-interface is enslaved into a bridge, an  in batadv_dat_snoop_outgoing_arp_request()
1180 		if (batadv_is_my_client(bat_priv, dat_entry->mac_addr, vid)) {  in batadv_dat_snoop_outgoing_arp_request()
1191 					    dat_entry->mac_addr, vid)) {  in batadv_dat_snoop_outgoing_arp_request()
1194 				   dat_entry->mac_addr);  in batadv_dat_snoop_outgoing_arp_request()
1200 						      dat_entry->mac_addr,  in batadv_dat_snoop_outgoing_arp_request()
1205 		skb_new->protocol = eth_type_trans(skb_new, soft_iface);  in batadv_dat_snoop_outgoing_arp_request()
1209 				   skb->len + ETH_HLEN + hdr_size);  in batadv_dat_snoop_outgoing_arp_request()
1225  * batadv_dat_snoop_incoming_arp_request() - snoop the ARP request and try to
1245 	if (!atomic_read(&bat_priv->distributed_arp_table))  in batadv_dat_snoop_incoming_arp_request()
1267 					      dat_entry->mac_addr, hw_src, vid);  in batadv_dat_snoop_incoming_arp_request()
1294  * batadv_dat_snoop_outgoing_arp_reply() - snoop the ARP reply and fill the DHT
1307 	if (!atomic_read(&bat_priv->distributed_arp_table))  in batadv_dat_snoop_outgoing_arp_reply()
1336  * batadv_dat_snoop_incoming_arp_reply() - snoop the ARP reply and fill the
1355 	if (!atomic_read(&bat_priv->distributed_arp_table))  in batadv_dat_snoop_incoming_arp_reply()
1378 	if (dat_entry && batadv_compare_eth(hw_src, dat_entry->mac_addr)) {  in batadv_dat_snoop_incoming_arp_reply()
1379 … bat_priv, "Doubled ARP reply removed: ARP MSG = [src: %pM-%pI4 dst: %pM-%pI4]; dat_entry: %pM-%pI…  in batadv_dat_snoop_incoming_arp_reply()
1381 			   dat_entry->mac_addr,	&dat_entry->ip);  in batadv_dat_snoop_incoming_arp_reply()
1421 	/* if dropped == false -> deliver to the interface */  in batadv_dat_snoop_incoming_arp_reply()
1426  * batadv_dat_check_dhcp_ipudp() - check skb for IP+UDP headers valid for DHCP
1444 	if (!iphdr || iphdr->version != 4 || iphdr->ihl * 4 < sizeof(_iphdr))  in batadv_dat_check_dhcp_ipudp()
1447 	if (iphdr->protocol != IPPROTO_UDP)  in batadv_dat_check_dhcp_ipudp()
1450 	offset += iphdr->ihl * 4;  in batadv_dat_check_dhcp_ipudp()
1454 	if (!udphdr || udphdr->source != htons(67))  in batadv_dat_check_dhcp_ipudp()
1457 	*ip_src = get_unaligned(&iphdr->saddr);  in batadv_dat_check_dhcp_ipudp()
1463  * batadv_dat_check_dhcp() - examine packet for valid DHCP message
1474  * (e.g. BOOTREPLY vs. BOOTREQUEST). Otherwise returns -EINVAL.
1489 		return -EINVAL;  in batadv_dat_check_dhcp()
1492 		return -EINVAL;  in batadv_dat_check_dhcp()
1495 	if (skb->len < offset + sizeof(struct batadv_dhcp_packet))  in batadv_dat_check_dhcp()
1496 		return -EINVAL;  in batadv_dat_check_dhcp()
1499 	if (!dhcp_h || dhcp_h->htype != BATADV_HTYPE_ETHERNET ||  in batadv_dat_check_dhcp()
1500 	    dhcp_h->hlen != ETH_ALEN)  in batadv_dat_check_dhcp()
1501 		return -EINVAL;  in batadv_dat_check_dhcp()
1507 		return -EINVAL;  in batadv_dat_check_dhcp()
1509 	return dhcp_h->op;  in batadv_dat_check_dhcp()
1513  * batadv_dat_get_dhcp_message_type() - get message type of a DHCP packet
1522  * Return: The found DHCP message type value, if found. -EINVAL otherwise.
1536 		if (tl->type == BATADV_DHCP_OPT_MSG_TYPE)  in batadv_dat_get_dhcp_message_type()
1539 		if (tl->type == BATADV_DHCP_OPT_END)  in batadv_dat_get_dhcp_message_type()
1542 		if (tl->type == BATADV_DHCP_OPT_PAD)  in batadv_dat_get_dhcp_message_type()
1545 			offset += tl->len + sizeof(_tl);  in batadv_dat_get_dhcp_message_type()
1549 	if (!tl || tl->type != BATADV_DHCP_OPT_MSG_TYPE ||  in batadv_dat_get_dhcp_message_type()
1550 	    tl->len != sizeof(_type))  in batadv_dat_get_dhcp_message_type()
1551 		return -EINVAL;  in batadv_dat_get_dhcp_message_type()
1557 		return -EINVAL;  in batadv_dat_get_dhcp_message_type()
1563  * batadv_dat_dhcp_get_yiaddr() - get yiaddr from a DHCP packet
1590  * batadv_dat_get_dhcp_chaddr() - get chaddr from a DHCP packet
1617  * batadv_dat_put_dhcp() - puts addresses from a DHCP packet into the DHT and
1664  * batadv_dat_check_dhcp_ack() - examine packet for valid DHCP message
1703  * batadv_dat_snoop_outgoing_dhcp_ack() - snoop DHCPACK and fill DAT with it
1725 	if (!atomic_read(&bat_priv->distributed_arp_table))  in batadv_dat_snoop_outgoing_dhcp_ack()
1731 	batadv_dat_put_dhcp(bat_priv, chaddr, yiaddr, eth_hdr(skb)->h_source,  in batadv_dat_snoop_outgoing_dhcp_ack()
1736  * batadv_dat_snoop_incoming_dhcp_ack() - snoop DHCPACK and fill DAT cache
1739  * @hdr_size: header size, up to the tail of the batman-adv header
1755 	if (!atomic_read(&bat_priv->distributed_arp_table))  in batadv_dat_snoop_incoming_dhcp_ack()
1761 	ethhdr = (struct ethhdr *)(skb->data + hdr_size);  in batadv_dat_snoop_incoming_dhcp_ack()
1763 	proto = ethhdr->h_proto;  in batadv_dat_snoop_incoming_dhcp_ack()
1768 	hw_src = ethhdr->h_source;  in batadv_dat_snoop_incoming_dhcp_ack()
1783  * batadv_dat_drop_broadcast_packet() - check if an ARP request has to be
1800 	if (!atomic_read(&bat_priv->distributed_arp_table))  in batadv_dat_drop_broadcast_packet()
1809 	vid = batadv_dat_get_vid(forw_packet->skb, &hdr_size);  in batadv_dat_drop_broadcast_packet()
1811 	type = batadv_arp_get_type(bat_priv, forw_packet->skb, hdr_size);  in batadv_dat_drop_broadcast_packet()
1815 	ip_dst = batadv_arp_ip_dst(forw_packet->skb, hdr_size);  in batadv_dat_drop_broadcast_packet()