1 /* Copyright (C) 2007-2017 B.A.T.M.A.N. contributors: 2 * 3 * Marek Lindner, Simon Wunderlich 4 * 5 * This program is free software; you can redistribute it and/or 6 * modify it under the terms of version 2 of the GNU General Public 7 * License as published by the Free Software Foundation. 8 * 9 * This program is distributed in the hope that it will be useful, but 10 * WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 12 * General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; if not, see <http://www.gnu.org/licenses/>. 16 */ 17 18 #include "main.h" 19 20 #include <linux/errno.h> 21 #include <linux/list.h> 22 #include <linux/moduleparam.h> 23 #include <linux/netlink.h> 24 #include <linux/printk.h> 25 #include <linux/seq_file.h> 26 #include <linux/skbuff.h> 27 #include <linux/stddef.h> 28 #include <linux/string.h> 29 #include <net/genetlink.h> 30 #include <net/netlink.h> 31 #include <uapi/linux/batman_adv.h> 32 33 #include "bat_algo.h" 34 #include "netlink.h" 35 36 char batadv_routing_algo[20] = "BATMAN_IV"; 37 static struct hlist_head batadv_algo_list; 38 39 /** 40 * batadv_algo_init - Initialize batman-adv algorithm management data structures 41 */ 42 void batadv_algo_init(void) 43 { 44 INIT_HLIST_HEAD(&batadv_algo_list); 45 } 46 47 static struct batadv_algo_ops *batadv_algo_get(char *name) 48 { 49 struct batadv_algo_ops *bat_algo_ops = NULL, *bat_algo_ops_tmp; 50 51 hlist_for_each_entry(bat_algo_ops_tmp, &batadv_algo_list, list) { 52 if (strcmp(bat_algo_ops_tmp->name, name) != 0) 53 continue; 54 55 bat_algo_ops = bat_algo_ops_tmp; 56 break; 57 } 58 59 return bat_algo_ops; 60 } 61 62 int batadv_algo_register(struct batadv_algo_ops *bat_algo_ops) 63 { 64 struct batadv_algo_ops *bat_algo_ops_tmp; 65 66 bat_algo_ops_tmp = batadv_algo_get(bat_algo_ops->name); 67 if (bat_algo_ops_tmp) { 68 pr_info("Trying to register already registered routing algorithm: %s\n", 69 bat_algo_ops->name); 70 return -EEXIST; 71 } 72 73 /* all algorithms must implement all ops (for now) */ 74 if (!bat_algo_ops->iface.enable || 75 !bat_algo_ops->iface.disable || 76 !bat_algo_ops->iface.update_mac || 77 !bat_algo_ops->iface.primary_set || 78 !bat_algo_ops->neigh.cmp || 79 !bat_algo_ops->neigh.is_similar_or_better) { 80 pr_info("Routing algo '%s' does not implement required ops\n", 81 bat_algo_ops->name); 82 return -EINVAL; 83 } 84 85 INIT_HLIST_NODE(&bat_algo_ops->list); 86 hlist_add_head(&bat_algo_ops->list, &batadv_algo_list); 87 88 return 0; 89 } 90 91 int batadv_algo_select(struct batadv_priv *bat_priv, char *name) 92 { 93 struct batadv_algo_ops *bat_algo_ops; 94 95 bat_algo_ops = batadv_algo_get(name); 96 if (!bat_algo_ops) 97 return -EINVAL; 98 99 bat_priv->algo_ops = bat_algo_ops; 100 101 return 0; 102 } 103 104 #ifdef CONFIG_BATMAN_ADV_DEBUGFS 105 int batadv_algo_seq_print_text(struct seq_file *seq, void *offset) 106 { 107 struct batadv_algo_ops *bat_algo_ops; 108 109 seq_puts(seq, "Available routing algorithms:\n"); 110 111 hlist_for_each_entry(bat_algo_ops, &batadv_algo_list, list) { 112 seq_printf(seq, " * %s\n", bat_algo_ops->name); 113 } 114 115 return 0; 116 } 117 #endif 118 119 static int batadv_param_set_ra(const char *val, const struct kernel_param *kp) 120 { 121 struct batadv_algo_ops *bat_algo_ops; 122 char *algo_name = (char *)val; 123 size_t name_len = strlen(algo_name); 124 125 if (name_len > 0 && algo_name[name_len - 1] == '\n') 126 algo_name[name_len - 1] = '\0'; 127 128 bat_algo_ops = batadv_algo_get(algo_name); 129 if (!bat_algo_ops) { 130 pr_err("Routing algorithm '%s' is not supported\n", algo_name); 131 return -EINVAL; 132 } 133 134 return param_set_copystring(algo_name, kp); 135 } 136 137 static const struct kernel_param_ops batadv_param_ops_ra = { 138 .set = batadv_param_set_ra, 139 .get = param_get_string, 140 }; 141 142 static struct kparam_string batadv_param_string_ra = { 143 .maxlen = sizeof(batadv_routing_algo), 144 .string = batadv_routing_algo, 145 }; 146 147 module_param_cb(routing_algo, &batadv_param_ops_ra, &batadv_param_string_ra, 148 0644); 149 150 /** 151 * batadv_algo_dump_entry - fill in information about one supported routing 152 * algorithm 153 * @msg: netlink message to be sent back 154 * @portid: Port to reply to 155 * @seq: Sequence number of message 156 * @bat_algo_ops: Algorithm to be dumped 157 * 158 * Return: Error number, or 0 on success 159 */ 160 static int batadv_algo_dump_entry(struct sk_buff *msg, u32 portid, u32 seq, 161 struct batadv_algo_ops *bat_algo_ops) 162 { 163 void *hdr; 164 165 hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family, 166 NLM_F_MULTI, BATADV_CMD_GET_ROUTING_ALGOS); 167 if (!hdr) 168 return -EMSGSIZE; 169 170 if (nla_put_string(msg, BATADV_ATTR_ALGO_NAME, bat_algo_ops->name)) 171 goto nla_put_failure; 172 173 genlmsg_end(msg, hdr); 174 return 0; 175 176 nla_put_failure: 177 genlmsg_cancel(msg, hdr); 178 return -EMSGSIZE; 179 } 180 181 /** 182 * batadv_algo_dump - fill in information about supported routing 183 * algorithms 184 * @msg: netlink message to be sent back 185 * @cb: Parameters to the netlink request 186 * 187 * Return: Length of reply message. 188 */ 189 int batadv_algo_dump(struct sk_buff *msg, struct netlink_callback *cb) 190 { 191 int portid = NETLINK_CB(cb->skb).portid; 192 struct batadv_algo_ops *bat_algo_ops; 193 int skip = cb->args[0]; 194 int i = 0; 195 196 hlist_for_each_entry(bat_algo_ops, &batadv_algo_list, list) { 197 if (i++ < skip) 198 continue; 199 200 if (batadv_algo_dump_entry(msg, portid, cb->nlh->nlmsg_seq, 201 bat_algo_ops)) { 202 i--; 203 break; 204 } 205 } 206 207 cb->args[0] = i; 208 209 return msg->len; 210 } 211