/* * Copyright (C) 2008-2010 B.A.T.M.A.N. contributors: * * 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, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA * 02110-1301, USA * */ #include "main.h" #include "send.h" #include "translation-table.h" #include "vis.h" #include "soft-interface.h" #include "hard-interface.h" #include "hash.h" /* Returns the smallest signed integer in two's complement with the sizeof x */ #define smallest_signed_int(x) (1u << (7u + 8u * (sizeof(x) - 1u))) /* Checks if a sequence number x is a predecessor/successor of y. they handle overflows/underflows and can correctly check for a predecessor/successor unless the variable sequence number has grown by more then 2**(bitwidth(x)-1)-1. This means that for a uint8_t with the maximum value 255, it would think: * when adding nothing - it is neither a predecessor nor a successor * before adding more than 127 to the starting value - it is a predecessor, * when adding 128 - it is neither a predecessor nor a successor, * after adding more than 127 to the starting value - it is a successor */ #define seq_before(x, y) ({typeof(x) _dummy = (x - y); \ _dummy > smallest_signed_int(_dummy); }) #define seq_after(x, y) seq_before(y, x) struct hashtable_t *vis_hash; DEFINE_SPINLOCK(vis_hash_lock); static DEFINE_SPINLOCK(recv_list_lock); static struct vis_info *my_vis_info; static struct list_head send_list; /* always locked with vis_hash_lock */ static void start_vis_timer(void); /* free the info */ static void free_info(struct kref *ref) { struct vis_info *info = container_of(ref, struct vis_info, refcount); struct recvlist_node *entry, *tmp; unsigned long flags; list_del_init(&info->send_list); spin_lock_irqsave(&recv_list_lock, flags); list_for_each_entry_safe(entry, tmp, &info->recv_list, list) { list_del(&entry->list); kfree(entry); } spin_unlock_irqrestore(&recv_list_lock, flags); kfree(info); } /* Compare two vis packets, used by the hashing algorithm */ static int vis_info_cmp(void *data1, void *data2) { struct vis_info *d1, *d2; d1 = data1; d2 = data2; return compare_orig(d1->packet.vis_orig, d2->packet.vis_orig); } /* hash function to choose an entry in a hash table of given size */ /* hash algorithm from http://en.wikipedia.org/wiki/Hash_table */ static int vis_info_choose(void *data, int size) { struct vis_info *vis_info = data; unsigned char *key; uint32_t hash = 0; size_t i; key = vis_info->packet.vis_orig; for (i = 0; i < ETH_ALEN; i++) { hash += key[i]; hash += (hash << 10); hash ^= (hash >> 6); } hash += (hash << 3); hash ^= (hash >> 11); hash += (hash << 15); return hash % size; } /* insert interface to the list of interfaces of one originator, if it * does not already exist in the list */ static void vis_data_insert_interface(const uint8_t *interface, struct hlist_head *if_list, bool primary) { struct if_list_entry *entry; struct hlist_node *pos; hlist_for_each_entry(entry, pos, if_list, list) { if (compare_orig(entry->addr, (void *)interface)) return; } /* its a new address, add it to the list */ entry = kmalloc(sizeof(*entry), GFP_KERNEL); if (!entry) return; memcpy(entry->addr, interface, ETH_ALEN); entry->primary = primary; hlist_add_head(&entry->list, if_list); } static ssize_t vis_data_read_prim_sec(char *buff, struct hlist_head *if_list) { struct if_list_entry *entry; struct hlist_node *pos; char tmp_addr_str[ETH_STR_LEN]; size_t len = 0; hlist_for_each_entry(entry, pos, if_list, list) { if (entry->primary) len += sprintf(buff + len, "PRIMARY, "); else { addr_to_string(tmp_addr_str, entry->addr); len += sprintf(buff + len, "SEC %s, ", tmp_addr_str); } } return len; } /* read an entry */ static ssize_t vis_data_read_entry(char *buff, struct vis_info_entry *entry, uint8_t *src, bool primary) { char to[40]; addr_to_string(to, entry->dest); if (primary && entry->quality == 0) return sprintf(buff, "HNA %s, ", to); else if (compare_orig(entry->src, src)) return sprintf(buff, "TQ %s %d, ", to, entry->quality); return 0; } ssize_t vis_fill_buffer_text(struct net_device *net_dev, char *buff, size_t count, loff_t off) { HASHIT(hashit); struct vis_info *info; struct vis_info_entry *entries; struct bat_priv *bat_priv = netdev_priv(net_dev); HLIST_HEAD(vis_if_list); struct if_list_entry *entry; struct hlist_node *pos, *n; size_t hdr_len, tmp_len; int i, bytes_written = 0; char tmp_addr_str[ETH_STR_LEN]; unsigned long flags; int vis_server = atomic_read(&bat_priv->vis_mode); if ((!bat_priv->primary_if) || (vis_server == VIS_TYPE_CLIENT_UPDATE)) return 0; hdr_len = 0; spin_lock_irqsave(&vis_hash_lock, flags); while (hash_iterate(vis_hash, &hashit)) { info = hashit.bucket->data; entries = (struct vis_info_entry *) ((char *)info + sizeof(struct vis_info)); /* estimated line length */ if (count < bytes_written + 200) break; for (i = 0; i < info->packet.entries; i++) { if (entries[i].quality == 0) continue; vis_data_insert_interface(entries[i].src, &vis_if_list, compare_orig(entries[i].src, info->packet.vis_orig)); } hlist_for_each_entry(entry, pos, &vis_if_list, list) { addr_to_string(tmp_addr_str, entry->addr); tmp_len = sprintf(buff + bytes_written, "%s,", tmp_addr_str); for (i = 0; i < info->packet.entries; i++) tmp_len += vis_data_read_entry( buff + bytes_written + tmp_len, &entries[i], entry->addr, entry->primary); /* add primary/secondary records */ if (compare_orig(entry->addr, info->packet.vis_orig)) tmp_len += vis_data_read_prim_sec( buff + bytes_written + tmp_len, &vis_if_list); tmp_len += sprintf(buff + bytes_written + tmp_len, "\n"); hdr_len += tmp_len; if (off >= hdr_len) continue; bytes_written += tmp_len; } hlist_for_each_entry_safe(entry, pos, n, &vis_if_list, list) { hlist_del(&entry->list); kfree(entry); } } spin_unlock_irqrestore(&vis_hash_lock, flags); return bytes_written; } /* add the info packet to the send list, if it was not * already linked in. */ static void send_list_add(struct vis_info *info) { if (list_empty(&info->send_list)) { kref_get(&info->refcount); list_add_tail(&info->send_list, &send_list); } } /* delete the info packet from the send list, if it was * linked in. */ static void send_list_del(struct vis_info *info) { if (!list_empty(&info->send_list)) { list_del_init(&info->send_list); kref_put(&info->refcount, free_info); } } /* tries to add one entry to the receive list. */ static void recv_list_add(struct list_head *recv_list, char *mac) { struct recvlist_node *entry; unsigned long flags; entry = kmalloc(sizeof(struct recvlist_node), GFP_ATOMIC); if (!entry) return; memcpy(entry->mac, mac, ETH_ALEN); spin_lock_irqsave(&recv_list_lock, flags); list_add_tail(&entry->list, recv_list); spin_unlock_irqrestore(&recv_list_lock, flags); } /* returns 1 if this mac is in the recv_list */ static int recv_list_is_in(struct list_head *recv_list, char *mac) { struct recvlist_node *entry; unsigned long flags; spin_lock_irqsave(&recv_list_lock, flags); list_for_each_entry(entry, recv_list, list) { if (memcmp(entry->mac, mac, ETH_ALEN) == 0) { spin_unlock_irqrestore(&recv_list_lock, flags); return 1; } } spin_unlock_irqrestore(&recv_list_lock, flags); return 0; } /* try to add the packet to the vis_hash. return NULL if invalid (e.g. too old, * broken.. ). vis hash must be locked outside. is_new is set when the packet * is newer than old entries in the hash. */ static struct vis_info *add_packet(struct vis_packet *vis_packet, int vis_info_len, int *is_new, int make_broadcast) { struct vis_info *info, *old_info; struct vis_info search_elem; *is_new = 0; /* sanity check */ if (vis_hash == NULL) return NULL; /* see if the packet is already in vis_hash */ memcpy(search_elem.packet.vis_orig, vis_packet->vis_orig, ETH_ALEN); old_info = hash_find(vis_hash, &search_elem); if (old_info != NULL) { if (!seq_after(vis_packet->seqno, old_info->packet.seqno)) { if (old_info->packet.seqno == vis_packet->seqno) { recv_list_add(&old_info->recv_list, vis_packet->sender_orig); return old_info; } else { /* newer packet is already in hash. */ return NULL; } } /* remove old entry */ hash_remove(vis_hash, old_info); send_list_del(old_info); kref_put(&old_info->refcount, free_info); } info = kmalloc(sizeof(struct vis_info) + vis_info_len, GFP_ATOMIC); if (info == NULL) return NULL; kref_init(&info->refcount); INIT_LIST_HEAD(&info->send_list); INIT_LIST_HEAD(&info->recv_list); info->first_seen = jiffies; memcpy(&info->packet, vis_packet, sizeof(struct vis_packet) + vis_info_len); /* initialize and add new packet. */ *is_new = 1; /* Make it a broadcast packet, if required */ if (make_broadcast) memcpy(info->packet.target_orig, broadcastAddr, ETH_ALEN); /* repair if entries is longer than packet. */ if (info->packet.entries * sizeof(struct vis_info_entry) > vis_info_len) info->packet.entries = vis_info_len / sizeof(struct vis_info_entry); recv_list_add(&info->recv_list, info->packet.sender_orig); /* try to add it */ if (hash_add(vis_hash, info) < 0) { /* did not work (for some reason) */ kref_put(&old_info->refcount, free_info); info = NULL; } return info; } /* handle the server sync packet, forward if needed. */ void receive_server_sync_packet(struct bat_priv *bat_priv, struct vis_packet *vis_packet, int vis_info_len) { struct vis_info *info; int is_new, make_broadcast; unsigned long flags; int vis_server = atomic_read(&bat_priv->vis_mode); make_broadcast = (vis_server == VIS_TYPE_SERVER_SYNC); spin_lock_irqsave(&vis_hash_lock, flags); info = add_packet(vis_packet, vis_info_len, &is_new, make_broadcast); if (info == NULL) goto end; /* only if we are server ourselves and packet is newer than the one in * hash.*/ if (vis_server == VIS_TYPE_SERVER_SYNC && is_new) send_list_add(info); end: spin_unlock_irqrestore(&vis_hash_lock, flags); } /* handle an incoming client update packet and schedule forward if needed. */ void receive_client_update_packet(struct bat_priv *bat_priv, struct vis_packet *vis_packet, int vis_info_len) { struct vis_info *info; int is_new; unsigned long flags; int vis_server = atomic_read(&bat_priv->vis_mode); int are_target = 0; /* clients shall not broadcast. */ if (is_bcast(vis_packet->target_orig)) return; /* Are we the target for this VIS packet? */ if (vis_server == VIS_TYPE_SERVER_SYNC && is_my_mac(vis_packet->target_orig)) are_target = 1; spin_lock_irqsave(&vis_hash_lock, flags); info = add_packet(vis_packet, vis_info_len, &is_new, are_target); if (info == NULL) goto end; /* note that outdated packets will be dropped at this point. */ /* send only if we're the target server or ... */ if (are_target && is_new) { info->packet.vis_type = VIS_TYPE_SERVER_SYNC; /* upgrade! */ send_list_add(info); /* ... we're not the recipient (and thus need to forward). */ } else if (!is_my_mac(info->packet.target_orig)) { send_list_add(info); } end: spin_unlock_irqrestore(&vis_hash_lock, flags); } /* Walk the originators and find the VIS server with the best tq. Set the packet * address to its address and return the best_tq. * * Must be called with the originator hash locked */ static int find_best_vis_server(struct vis_info *info) { HASHIT(hashit); struct orig_node *orig_node; int best_tq = -1; while (hash_iterate(orig_hash, &hashit)) { orig_node = hashit.bucket->data; if ((orig_node != NULL) && (orig_node->router != NULL) && (orig_node->flags & VIS_SERVER) && (orig_node->router->tq_avg > best_tq)) { best_tq = orig_node->router->tq_avg; memcpy(info->packet.target_orig, orig_node->orig, ETH_ALEN); } } return best_tq; } /* Return true if the vis packet is full. */ static bool vis_packet_full(struct vis_info *info) { if (info->packet.entries + 1 > (1000 - sizeof(struct vis_info)) / sizeof(struct vis_info_entry)) return true; return false; } /* generates a packet of own vis data, * returns 0 on success, -1 if no packet could be generated */ static int generate_vis_packet(struct bat_priv *bat_priv) { HASHIT(hashit_local); HASHIT(hashit_global); struct orig_node *orig_node; struct vis_info *info = (struct vis_info *)my_vis_info; struct vis_info_entry *entry, *entry_array; struct hna_local_entry *hna_local_entry; int best_tq = -1; unsigned long flags; info->first_seen = jiffies; info->packet.vis_type = atomic_read(&bat_priv->vis_mode); spin_lock_irqsave(&orig_hash_lock, flags); memcpy(info->packet.target_orig, broadcastAddr, ETH_ALEN); info->packet.ttl = TTL; info->packet.seqno++; info->packet.entries = 0; if (info->packet.vis_type == VIS_TYPE_CLIENT_UPDATE) { best_tq = find_best_vis_server(info); if (best_tq < 0) { spin_unlock_irqrestore(&orig_hash_lock, flags); return -1; } } entry_array = (struct vis_info_entry *) ((char *)info + sizeof(struct vis_info)); while (hash_iterate(orig_hash, &hashit_global)) { orig_node = hashit_global.bucket->data; if (orig_node->router != NULL && compare_orig(orig_node->router->addr, orig_node->orig) && (orig_node->router->if_incoming->if_status == IF_ACTIVE) && orig_node->router->tq_avg > 0) { /* fill one entry into buffer. */ entry = &entry_array[info->packet.entries]; memcpy(entry->src, orig_node->router->if_incoming->net_dev->dev_addr, ETH_ALEN); memcpy(entry->dest, orig_node->orig, ETH_ALEN); entry->quality = orig_node->router->tq_avg; info->packet.entries++; if (vis_packet_full(info)) { spin_unlock_irqrestore(&orig_hash_lock, flags); return 0; } } } spin_unlock_irqrestore(&orig_hash_lock, flags); spin_lock_irqsave(&hna_local_hash_lock, flags); while (hash_iterate(hna_local_hash, &hashit_local)) { hna_local_entry = hashit_local.bucket->data; entry = &entry_array[info->packet.entries]; memset(entry->src, 0, ETH_ALEN); memcpy(entry->dest, hna_local_entry->addr, ETH_ALEN); entry->quality = 0; /* 0 means HNA */ info->packet.entries++; if (vis_packet_full(info)) { spin_unlock_irqrestore(&hna_local_hash_lock, flags); return 0; } } spin_unlock_irqrestore(&hna_local_hash_lock, flags); return 0; } /* free old vis packets. Must be called with this vis_hash_lock * held */ static void purge_vis_packets(void) { HASHIT(hashit); struct vis_info *info; while (hash_iterate(vis_hash, &hashit)) { info = hashit.bucket->data; if (info == my_vis_info) /* never purge own data. */ continue; if (time_after(jiffies, info->first_seen + (VIS_TIMEOUT*HZ)/1000)) { hash_remove_bucket(vis_hash, &hashit); send_list_del(info); kref_put(&info->refcount, free_info); } } } static void broadcast_vis_packet(struct vis_info *info, int packet_length) { HASHIT(hashit); struct orig_node *orig_node; unsigned long flags; struct batman_if *batman_if; uint8_t dstaddr[ETH_ALEN]; spin_lock_irqsave(&orig_hash_lock, flags); /* send to all routers in range. */ while (hash_iterate(orig_hash, &hashit)) { orig_node = hashit.bucket->data; /* if it's a vis server and reachable, send it. */ if ((!orig_node) || (!orig_node->router)) continue; if (!(orig_node->flags & VIS_SERVER)) continue; /* don't send it if we already received the packet from * this node. */ if (recv_list_is_in(&info->recv_list, orig_node->orig)) continue; memcpy(info->packet.target_orig, orig_node->orig, ETH_ALEN); batman_if = orig_node->router->if_incoming; memcpy(dstaddr, orig_node->router->addr, ETH_ALEN); spin_unlock_irqrestore(&orig_hash_lock, flags); send_raw_packet((unsigned char *)&info->packet, packet_length, batman_if, dstaddr); spin_lock_irqsave(&orig_hash_lock, flags); } spin_unlock_irqrestore(&orig_hash_lock, flags); memcpy(info->packet.target_orig, broadcastAddr, ETH_ALEN); } static void unicast_vis_packet(struct vis_info *info, int packet_length) { struct orig_node *orig_node; unsigned long flags; struct batman_if *batman_if; uint8_t dstaddr[ETH_ALEN]; spin_lock_irqsave(&orig_hash_lock, flags); orig_node = ((struct orig_node *) hash_find(orig_hash, info->packet.target_orig)); if ((!orig_node) || (!orig_node->router)) goto out; /* don't lock while sending the packets ... we therefore * copy the required data before sending */ batman_if = orig_node->router->if_incoming; memcpy(dstaddr, orig_node->router->addr, ETH_ALEN); spin_unlock_irqrestore(&orig_hash_lock, flags); send_raw_packet((unsigned char *)&info->packet, packet_length, batman_if, dstaddr); return; out: spin_unlock_irqrestore(&orig_hash_lock, flags); } /* only send one vis packet. called from send_vis_packets() */ static void send_vis_packet(struct vis_info *info) { int packet_length; if (info->packet.ttl < 2) { printk(KERN_WARNING "batman-adv: Error - can't send vis packet: ttl exceeded\n"); return; } memcpy(info->packet.sender_orig, mainIfAddr, ETH_ALEN); info->packet.ttl--; packet_length = sizeof(struct vis_packet) + info->packet.entries * sizeof(struct vis_info_entry); if (is_bcast(info->packet.target_orig)) broadcast_vis_packet(info, packet_length); else unicast_vis_packet(info, packet_length); info->packet.ttl++; /* restore TTL */ } /* called from timer; send (and maybe generate) vis packet. */ static void send_vis_packets(struct work_struct *work) { struct vis_info *info, *temp; unsigned long flags; /* FIXME: each batman_if will be attached to a softif */ struct bat_priv *bat_priv = netdev_priv(soft_device); spin_lock_irqsave(&vis_hash_lock, flags); purge_vis_packets(); if (generate_vis_packet(bat_priv) == 0) { /* schedule if generation was successful */ send_list_add(my_vis_info); } list_for_each_entry_safe(info, temp, &send_list, send_list) { kref_get(&info->refcount); spin_unlock_irqrestore(&vis_hash_lock, flags); send_vis_packet(info); spin_lock_irqsave(&vis_hash_lock, flags); send_list_del(info); kref_put(&info->refcount, free_info); } spin_unlock_irqrestore(&vis_hash_lock, flags); start_vis_timer(); } static DECLARE_DELAYED_WORK(vis_timer_wq, send_vis_packets); /* init the vis server. this may only be called when if_list is already * initialized (e.g. bat0 is initialized, interfaces have been added) */ int vis_init(void) { unsigned long flags; if (vis_hash) return 1; spin_lock_irqsave(&vis_hash_lock, flags); vis_hash = hash_new(256, vis_info_cmp, vis_info_choose); if (!vis_hash) { printk(KERN_ERR "batman-adv:Can't initialize vis_hash\n"); goto err; } my_vis_info = kmalloc(1000, GFP_ATOMIC); if (!my_vis_info) { printk(KERN_ERR "batman-adv:Can't initialize vis packet\n"); goto err; } /* prefill the vis info */ my_vis_info->first_seen = jiffies - atomic_read(&vis_interval); INIT_LIST_HEAD(&my_vis_info->recv_list); INIT_LIST_HEAD(&my_vis_info->send_list); kref_init(&my_vis_info->refcount); my_vis_info->packet.version = COMPAT_VERSION; my_vis_info->packet.packet_type = BAT_VIS; my_vis_info->packet.ttl = TTL; my_vis_info->packet.seqno = 0; my_vis_info->packet.entries = 0; INIT_LIST_HEAD(&send_list); memcpy(my_vis_info->packet.vis_orig, mainIfAddr, ETH_ALEN); memcpy(my_vis_info->packet.sender_orig, mainIfAddr, ETH_ALEN); if (hash_add(vis_hash, my_vis_info) < 0) { printk(KERN_ERR "batman-adv:Can't add own vis packet into hash\n"); /* not in hash, need to remove it manually. */ kref_put(&my_vis_info->refcount, free_info); goto err; } spin_unlock_irqrestore(&vis_hash_lock, flags); start_vis_timer(); return 1; err: spin_unlock_irqrestore(&vis_hash_lock, flags); vis_quit(); return 0; } /* Decrease the reference count on a hash item info */ static void free_info_ref(void *data) { struct vis_info *info = data; send_list_del(info); kref_put(&info->refcount, free_info); } /* shutdown vis-server */ void vis_quit(void) { unsigned long flags; if (!vis_hash) return; cancel_delayed_work_sync(&vis_timer_wq); spin_lock_irqsave(&vis_hash_lock, flags); /* properly remove, kill timers ... */ hash_delete(vis_hash, free_info_ref); vis_hash = NULL; my_vis_info = NULL; spin_unlock_irqrestore(&vis_hash_lock, flags); } /* schedule packets for (re)transmission */ static void start_vis_timer(void) { queue_delayed_work(bat_event_workqueue, &vis_timer_wq, (atomic_read(&vis_interval) * HZ) / 1000); }