1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * File: pn_netlink.c |
4 | * |
5 | * Phonet netlink interface |
6 | * |
7 | * Copyright (C) 2008 Nokia Corporation. |
8 | * |
9 | * Authors: Sakari Ailus <sakari.ailus@nokia.com> |
10 | * Remi Denis-Courmont |
11 | */ |
12 | |
13 | #include <linux/kernel.h> |
14 | #include <linux/netlink.h> |
15 | #include <linux/phonet.h> |
16 | #include <linux/slab.h> |
17 | #include <net/sock.h> |
18 | #include <net/phonet/pn_dev.h> |
19 | |
20 | /* Device address handling */ |
21 | |
22 | static int fill_addr(struct sk_buff *skb, struct net_device *dev, u8 addr, |
23 | u32 portid, u32 seq, int event); |
24 | |
25 | void phonet_address_notify(int event, struct net_device *dev, u8 addr) |
26 | { |
27 | struct sk_buff *skb; |
28 | int err = -ENOBUFS; |
29 | |
30 | skb = nlmsg_new(NLMSG_ALIGN(sizeof(struct ifaddrmsg)) + |
31 | nla_total_size(payload: 1), GFP_KERNEL); |
32 | if (skb == NULL) |
33 | goto errout; |
34 | err = fill_addr(skb, dev, addr, portid: 0, seq: 0, event); |
35 | if (err < 0) { |
36 | WARN_ON(err == -EMSGSIZE); |
37 | kfree_skb(skb); |
38 | goto errout; |
39 | } |
40 | rtnl_notify(skb, net: dev_net(dev), pid: 0, |
41 | RTNLGRP_PHONET_IFADDR, NULL, GFP_KERNEL); |
42 | return; |
43 | errout: |
44 | rtnl_set_sk_err(net: dev_net(dev), RTNLGRP_PHONET_IFADDR, error: err); |
45 | } |
46 | |
47 | static const struct nla_policy ifa_phonet_policy[IFA_MAX+1] = { |
48 | [IFA_LOCAL] = { .type = NLA_U8 }, |
49 | }; |
50 | |
51 | static int addr_doit(struct sk_buff *skb, struct nlmsghdr *nlh, |
52 | struct netlink_ext_ack *extack) |
53 | { |
54 | struct net *net = sock_net(sk: skb->sk); |
55 | struct nlattr *tb[IFA_MAX+1]; |
56 | struct net_device *dev; |
57 | struct ifaddrmsg *ifm; |
58 | int err; |
59 | u8 pnaddr; |
60 | |
61 | if (!netlink_capable(skb, CAP_NET_ADMIN)) |
62 | return -EPERM; |
63 | |
64 | if (!netlink_capable(skb, CAP_SYS_ADMIN)) |
65 | return -EPERM; |
66 | |
67 | ASSERT_RTNL(); |
68 | |
69 | err = nlmsg_parse_deprecated(nlh, hdrlen: sizeof(*ifm), tb, IFA_MAX, |
70 | policy: ifa_phonet_policy, extack); |
71 | if (err < 0) |
72 | return err; |
73 | |
74 | ifm = nlmsg_data(nlh); |
75 | if (tb[IFA_LOCAL] == NULL) |
76 | return -EINVAL; |
77 | pnaddr = nla_get_u8(nla: tb[IFA_LOCAL]); |
78 | if (pnaddr & 3) |
79 | /* Phonet addresses only have 6 high-order bits */ |
80 | return -EINVAL; |
81 | |
82 | dev = __dev_get_by_index(net, ifindex: ifm->ifa_index); |
83 | if (dev == NULL) |
84 | return -ENODEV; |
85 | |
86 | if (nlh->nlmsg_type == RTM_NEWADDR) |
87 | err = phonet_address_add(dev, addr: pnaddr); |
88 | else |
89 | err = phonet_address_del(dev, addr: pnaddr); |
90 | if (!err) |
91 | phonet_address_notify(event: nlh->nlmsg_type, dev, addr: pnaddr); |
92 | return err; |
93 | } |
94 | |
95 | static int fill_addr(struct sk_buff *skb, struct net_device *dev, u8 addr, |
96 | u32 portid, u32 seq, int event) |
97 | { |
98 | struct ifaddrmsg *ifm; |
99 | struct nlmsghdr *nlh; |
100 | |
101 | nlh = nlmsg_put(skb, portid, seq, type: event, payload: sizeof(*ifm), flags: 0); |
102 | if (nlh == NULL) |
103 | return -EMSGSIZE; |
104 | |
105 | ifm = nlmsg_data(nlh); |
106 | ifm->ifa_family = AF_PHONET; |
107 | ifm->ifa_prefixlen = 0; |
108 | ifm->ifa_flags = IFA_F_PERMANENT; |
109 | ifm->ifa_scope = RT_SCOPE_LINK; |
110 | ifm->ifa_index = dev->ifindex; |
111 | if (nla_put_u8(skb, attrtype: IFA_LOCAL, value: addr)) |
112 | goto nla_put_failure; |
113 | nlmsg_end(skb, nlh); |
114 | return 0; |
115 | |
116 | nla_put_failure: |
117 | nlmsg_cancel(skb, nlh); |
118 | return -EMSGSIZE; |
119 | } |
120 | |
121 | static int getaddr_dumpit(struct sk_buff *skb, struct netlink_callback *cb) |
122 | { |
123 | struct phonet_device_list *pndevs; |
124 | struct phonet_device *pnd; |
125 | int dev_idx = 0, dev_start_idx = cb->args[0]; |
126 | int addr_idx = 0, addr_start_idx = cb->args[1]; |
127 | |
128 | pndevs = phonet_device_list(net: sock_net(sk: skb->sk)); |
129 | rcu_read_lock(); |
130 | list_for_each_entry_rcu(pnd, &pndevs->list, list) { |
131 | u8 addr; |
132 | |
133 | if (dev_idx > dev_start_idx) |
134 | addr_start_idx = 0; |
135 | if (dev_idx++ < dev_start_idx) |
136 | continue; |
137 | |
138 | addr_idx = 0; |
139 | for_each_set_bit(addr, pnd->addrs, 64) { |
140 | if (addr_idx++ < addr_start_idx) |
141 | continue; |
142 | |
143 | if (fill_addr(skb, dev: pnd->netdev, addr: addr << 2, |
144 | NETLINK_CB(cb->skb).portid, |
145 | seq: cb->nlh->nlmsg_seq, RTM_NEWADDR) < 0) |
146 | goto out; |
147 | } |
148 | } |
149 | |
150 | out: |
151 | rcu_read_unlock(); |
152 | cb->args[0] = dev_idx; |
153 | cb->args[1] = addr_idx; |
154 | |
155 | return skb->len; |
156 | } |
157 | |
158 | /* Routes handling */ |
159 | |
160 | static int fill_route(struct sk_buff *skb, struct net_device *dev, u8 dst, |
161 | u32 portid, u32 seq, int event) |
162 | { |
163 | struct rtmsg *rtm; |
164 | struct nlmsghdr *nlh; |
165 | |
166 | nlh = nlmsg_put(skb, portid, seq, type: event, payload: sizeof(*rtm), flags: 0); |
167 | if (nlh == NULL) |
168 | return -EMSGSIZE; |
169 | |
170 | rtm = nlmsg_data(nlh); |
171 | rtm->rtm_family = AF_PHONET; |
172 | rtm->rtm_dst_len = 6; |
173 | rtm->rtm_src_len = 0; |
174 | rtm->rtm_tos = 0; |
175 | rtm->rtm_table = RT_TABLE_MAIN; |
176 | rtm->rtm_protocol = RTPROT_STATIC; |
177 | rtm->rtm_scope = RT_SCOPE_UNIVERSE; |
178 | rtm->rtm_type = RTN_UNICAST; |
179 | rtm->rtm_flags = 0; |
180 | if (nla_put_u8(skb, attrtype: RTA_DST, value: dst) || |
181 | nla_put_u32(skb, attrtype: RTA_OIF, value: dev->ifindex)) |
182 | goto nla_put_failure; |
183 | nlmsg_end(skb, nlh); |
184 | return 0; |
185 | |
186 | nla_put_failure: |
187 | nlmsg_cancel(skb, nlh); |
188 | return -EMSGSIZE; |
189 | } |
190 | |
191 | void rtm_phonet_notify(int event, struct net_device *dev, u8 dst) |
192 | { |
193 | struct sk_buff *skb; |
194 | int err = -ENOBUFS; |
195 | |
196 | skb = nlmsg_new(NLMSG_ALIGN(sizeof(struct ifaddrmsg)) + |
197 | nla_total_size(payload: 1) + nla_total_size(payload: 4), GFP_KERNEL); |
198 | if (skb == NULL) |
199 | goto errout; |
200 | err = fill_route(skb, dev, dst, portid: 0, seq: 0, event); |
201 | if (err < 0) { |
202 | WARN_ON(err == -EMSGSIZE); |
203 | kfree_skb(skb); |
204 | goto errout; |
205 | } |
206 | rtnl_notify(skb, net: dev_net(dev), pid: 0, |
207 | RTNLGRP_PHONET_ROUTE, NULL, GFP_KERNEL); |
208 | return; |
209 | errout: |
210 | rtnl_set_sk_err(net: dev_net(dev), RTNLGRP_PHONET_ROUTE, error: err); |
211 | } |
212 | |
213 | static const struct nla_policy rtm_phonet_policy[RTA_MAX+1] = { |
214 | [RTA_DST] = { .type = NLA_U8 }, |
215 | [RTA_OIF] = { .type = NLA_U32 }, |
216 | }; |
217 | |
218 | static int route_doit(struct sk_buff *skb, struct nlmsghdr *nlh, |
219 | struct netlink_ext_ack *extack) |
220 | { |
221 | struct net *net = sock_net(sk: skb->sk); |
222 | struct nlattr *tb[RTA_MAX+1]; |
223 | struct net_device *dev; |
224 | struct rtmsg *rtm; |
225 | int err; |
226 | u8 dst; |
227 | |
228 | if (!netlink_capable(skb, CAP_NET_ADMIN)) |
229 | return -EPERM; |
230 | |
231 | if (!netlink_capable(skb, CAP_SYS_ADMIN)) |
232 | return -EPERM; |
233 | |
234 | ASSERT_RTNL(); |
235 | |
236 | err = nlmsg_parse_deprecated(nlh, hdrlen: sizeof(*rtm), tb, RTA_MAX, |
237 | policy: rtm_phonet_policy, extack); |
238 | if (err < 0) |
239 | return err; |
240 | |
241 | rtm = nlmsg_data(nlh); |
242 | if (rtm->rtm_table != RT_TABLE_MAIN || rtm->rtm_type != RTN_UNICAST) |
243 | return -EINVAL; |
244 | if (tb[RTA_DST] == NULL || tb[RTA_OIF] == NULL) |
245 | return -EINVAL; |
246 | dst = nla_get_u8(nla: tb[RTA_DST]); |
247 | if (dst & 3) /* Phonet addresses only have 6 high-order bits */ |
248 | return -EINVAL; |
249 | |
250 | dev = __dev_get_by_index(net, ifindex: nla_get_u32(nla: tb[RTA_OIF])); |
251 | if (dev == NULL) |
252 | return -ENODEV; |
253 | |
254 | if (nlh->nlmsg_type == RTM_NEWROUTE) |
255 | err = phonet_route_add(dev, daddr: dst); |
256 | else |
257 | err = phonet_route_del(dev, daddr: dst); |
258 | if (!err) |
259 | rtm_phonet_notify(event: nlh->nlmsg_type, dev, dst); |
260 | return err; |
261 | } |
262 | |
263 | static int route_dumpit(struct sk_buff *skb, struct netlink_callback *cb) |
264 | { |
265 | struct net *net = sock_net(sk: skb->sk); |
266 | u8 addr; |
267 | |
268 | rcu_read_lock(); |
269 | for (addr = cb->args[0]; addr < 64; addr++) { |
270 | struct net_device *dev = phonet_route_get_rcu(net, daddr: addr << 2); |
271 | |
272 | if (!dev) |
273 | continue; |
274 | |
275 | if (fill_route(skb, dev, dst: addr << 2, NETLINK_CB(cb->skb).portid, |
276 | seq: cb->nlh->nlmsg_seq, RTM_NEWROUTE) < 0) |
277 | goto out; |
278 | } |
279 | |
280 | out: |
281 | rcu_read_unlock(); |
282 | cb->args[0] = addr; |
283 | |
284 | return skb->len; |
285 | } |
286 | |
287 | int __init phonet_netlink_register(void) |
288 | { |
289 | int err = rtnl_register_module(THIS_MODULE, PF_PHONET, RTM_NEWADDR, |
290 | addr_doit, NULL, flags: 0); |
291 | if (err) |
292 | return err; |
293 | |
294 | /* Further rtnl_register_module() cannot fail */ |
295 | rtnl_register_module(THIS_MODULE, PF_PHONET, RTM_DELADDR, |
296 | addr_doit, NULL, flags: 0); |
297 | rtnl_register_module(THIS_MODULE, PF_PHONET, RTM_GETADDR, |
298 | NULL, getaddr_dumpit, flags: 0); |
299 | rtnl_register_module(THIS_MODULE, PF_PHONET, RTM_NEWROUTE, |
300 | route_doit, NULL, flags: 0); |
301 | rtnl_register_module(THIS_MODULE, PF_PHONET, RTM_DELROUTE, |
302 | route_doit, NULL, flags: 0); |
303 | rtnl_register_module(THIS_MODULE, PF_PHONET, RTM_GETROUTE, |
304 | NULL, route_dumpit, flags: 0); |
305 | return 0; |
306 | } |
307 | |