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(name: 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(h: &bat_algo_ops->list); |
87 | hlist_add_head(n: &bat_algo_ops->list, h: &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(name: 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(val: 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(skb: msg, portid, seq, family: &batadv_netlink_family, |
165 | NLM_F_MULTI, cmd: BATADV_CMD_GET_ROUTING_ALGOS); |
166 | if (!hdr) |
167 | return -EMSGSIZE; |
168 | |
169 | if (nla_put_string(skb: msg, attrtype: BATADV_ATTR_ALGO_NAME, str: bat_algo_ops->name)) |
170 | goto nla_put_failure; |
171 | |
172 | genlmsg_end(skb: msg, hdr); |
173 | return 0; |
174 | |
175 | nla_put_failure: |
176 | genlmsg_cancel(skb: 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, seq: 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 | |