1 // SPDX-License-Identifier: GPL-2.0 2 /* Copyright (C) B.A.T.M.A.N. contributors: 3 * 4 * Marek Lindner, Simon Wunderlich 5 */ 6 7 #include "main.h" 8 9 #include <linux/errno.h> 10 #include <linux/list.h> 11 #include <linux/moduleparam.h> 12 #include <linux/netlink.h> 13 #include <linux/printk.h> 14 #include <linux/skbuff.h> 15 #include <linux/stddef.h> 16 #include <linux/string.h> 17 #include <net/genetlink.h> 18 #include <net/netlink.h> 19 #include <uapi/linux/batman_adv.h> 20 21 #include "bat_algo.h" 22 #include "netlink.h" 23 24 char batadv_routing_algo[20] = "BATMAN_IV"; 25 static struct hlist_head batadv_algo_list; 26 27 /** 28 * batadv_algo_init() - Initialize batman-adv algorithm management data 29 * structures 30 */ 31 void batadv_algo_init(void) 32 { 33 INIT_HLIST_HEAD(&batadv_algo_list); 34 } 35 36 /** 37 * batadv_algo_get() - Search for algorithm with specific name 38 * @name: algorithm name to find 39 * 40 * Return: Pointer to batadv_algo_ops on success, NULL otherwise 41 */ 42 struct batadv_algo_ops *batadv_algo_get(const char *name) 43 { 44 struct batadv_algo_ops *bat_algo_ops = NULL, *bat_algo_ops_tmp; 45 46 hlist_for_each_entry(bat_algo_ops_tmp, &batadv_algo_list, list) { 47 if (strcmp(bat_algo_ops_tmp->name, name) != 0) 48 continue; 49 50 bat_algo_ops = bat_algo_ops_tmp; 51 break; 52 } 53 54 return bat_algo_ops; 55 } 56 57 /** 58 * batadv_algo_register() - Register callbacks for a mesh algorithm 59 * @bat_algo_ops: mesh algorithm callbacks to add 60 * 61 * Return: 0 on success or negative error number in case of failure 62 */ 63 int batadv_algo_register(struct batadv_algo_ops *bat_algo_ops) 64 { 65 struct batadv_algo_ops *bat_algo_ops_tmp; 66 67 bat_algo_ops_tmp = batadv_algo_get(bat_algo_ops->name); 68 if (bat_algo_ops_tmp) { 69 pr_info("Trying to register already registered routing algorithm: %s\n", 70 bat_algo_ops->name); 71 return -EEXIST; 72 } 73 74 /* all algorithms must implement all ops (for now) */ 75 if (!bat_algo_ops->iface.enable || 76 !bat_algo_ops->iface.disable || 77 !bat_algo_ops->iface.update_mac || 78 !bat_algo_ops->iface.primary_set || 79 !bat_algo_ops->neigh.cmp || 80 !bat_algo_ops->neigh.is_similar_or_better) { 81 pr_info("Routing algo '%s' does not implement required ops\n", 82 bat_algo_ops->name); 83 return -EINVAL; 84 } 85 86 INIT_HLIST_NODE(&bat_algo_ops->list); 87 hlist_add_head(&bat_algo_ops->list, &batadv_algo_list); 88 89 return 0; 90 } 91 92 /** 93 * batadv_algo_select() - Select algorithm of soft interface 94 * @bat_priv: the bat priv with all the soft interface information 95 * @name: name of the algorithm to select 96 * 97 * The algorithm callbacks for the soft interface will be set when the algorithm 98 * with the correct name was found. Any previous selected algorithm will not be 99 * deinitialized and the new selected algorithm will also not be initialized. 100 * It is therefore not allowed to call batadv_algo_select outside the creation 101 * function of the soft interface. 102 * 103 * Return: 0 on success or negative error number in case of failure 104 */ 105 int batadv_algo_select(struct batadv_priv *bat_priv, const char *name) 106 { 107 struct batadv_algo_ops *bat_algo_ops; 108 109 bat_algo_ops = batadv_algo_get(name); 110 if (!bat_algo_ops) 111 return -EINVAL; 112 113 bat_priv->algo_ops = bat_algo_ops; 114 115 return 0; 116 } 117 118 static int batadv_param_set_ra(const char *val, const struct kernel_param *kp) 119 { 120 struct batadv_algo_ops *bat_algo_ops; 121 char *algo_name = (char *)val; 122 size_t name_len = strlen(algo_name); 123 124 if (name_len > 0 && algo_name[name_len - 1] == '\n') 125 algo_name[name_len - 1] = '\0'; 126 127 bat_algo_ops = batadv_algo_get(algo_name); 128 if (!bat_algo_ops) { 129 pr_err("Routing algorithm '%s' is not supported\n", algo_name); 130 return -EINVAL; 131 } 132 133 return param_set_copystring(algo_name, kp); 134 } 135 136 static const struct kernel_param_ops batadv_param_ops_ra = { 137 .set = batadv_param_set_ra, 138 .get = param_get_string, 139 }; 140 141 static struct kparam_string batadv_param_string_ra = { 142 .maxlen = sizeof(batadv_routing_algo), 143 .string = batadv_routing_algo, 144 }; 145 146 module_param_cb(routing_algo, &batadv_param_ops_ra, &batadv_param_string_ra, 147 0644); 148 149 /** 150 * batadv_algo_dump_entry() - fill in information about one supported routing 151 * algorithm 152 * @msg: netlink message to be sent back 153 * @portid: Port to reply to 154 * @seq: Sequence number of message 155 * @bat_algo_ops: Algorithm to be dumped 156 * 157 * Return: Error number, or 0 on success 158 */ 159 static int batadv_algo_dump_entry(struct sk_buff *msg, u32 portid, u32 seq, 160 struct batadv_algo_ops *bat_algo_ops) 161 { 162 void *hdr; 163 164 hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family, 165 NLM_F_MULTI, BATADV_CMD_GET_ROUTING_ALGOS); 166 if (!hdr) 167 return -EMSGSIZE; 168 169 if (nla_put_string(msg, BATADV_ATTR_ALGO_NAME, bat_algo_ops->name)) 170 goto nla_put_failure; 171 172 genlmsg_end(msg, hdr); 173 return 0; 174 175 nla_put_failure: 176 genlmsg_cancel(msg, hdr); 177 return -EMSGSIZE; 178 } 179 180 /** 181 * batadv_algo_dump() - fill in information about supported routing 182 * algorithms 183 * @msg: netlink message to be sent back 184 * @cb: Parameters to the netlink request 185 * 186 * Return: Length of reply message. 187 */ 188 int batadv_algo_dump(struct sk_buff *msg, struct netlink_callback *cb) 189 { 190 int portid = NETLINK_CB(cb->skb).portid; 191 struct batadv_algo_ops *bat_algo_ops; 192 int skip = cb->args[0]; 193 int i = 0; 194 195 hlist_for_each_entry(bat_algo_ops, &batadv_algo_list, list) { 196 if (i++ < skip) 197 continue; 198 199 if (batadv_algo_dump_entry(msg, portid, cb->nlh->nlmsg_seq, 200 bat_algo_ops)) { 201 i--; 202 break; 203 } 204 } 205 206 cb->args[0] = i; 207 208 return msg->len; 209 } 210