1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *	Bridge per vlan tunnel port dst_metadata netlink control interface
4  *
5  *	Authors:
6  *	Roopa Prabhu		<roopa@cumulusnetworks.com>
7  */
8 
9 #include <linux/kernel.h>
10 #include <linux/slab.h>
11 #include <linux/etherdevice.h>
12 #include <net/rtnetlink.h>
13 #include <net/net_namespace.h>
14 #include <net/sock.h>
15 #include <uapi/linux/if_bridge.h>
16 #include <net/dst_metadata.h>
17 
18 #include "br_private.h"
19 #include "br_private_tunnel.h"
20 
21 static size_t __get_vlan_tinfo_size(void)
22 {
23 	return nla_total_size(0) + /* nest IFLA_BRIDGE_VLAN_TUNNEL_INFO */
24 		  nla_total_size(sizeof(u32)) + /* IFLA_BRIDGE_VLAN_TUNNEL_ID */
25 		  nla_total_size(sizeof(u16)) + /* IFLA_BRIDGE_VLAN_TUNNEL_VID */
26 		  nla_total_size(sizeof(u16)); /* IFLA_BRIDGE_VLAN_TUNNEL_FLAGS */
27 }
28 
29 bool vlan_tunid_inrange(const struct net_bridge_vlan *v_curr,
30 			const struct net_bridge_vlan *v_last)
31 {
32 	__be32 tunid_curr = tunnel_id_to_key32(v_curr->tinfo.tunnel_id);
33 	__be32 tunid_last = tunnel_id_to_key32(v_last->tinfo.tunnel_id);
34 
35 	return (be32_to_cpu(tunid_curr) - be32_to_cpu(tunid_last)) == 1;
36 }
37 
38 static int __get_num_vlan_tunnel_infos(struct net_bridge_vlan_group *vg)
39 {
40 	struct net_bridge_vlan *v, *vtbegin = NULL, *vtend = NULL;
41 	int num_tinfos = 0;
42 
43 	/* Count number of vlan infos */
44 	list_for_each_entry_rcu(v, &vg->vlan_list, vlist) {
45 		/* only a context, bridge vlan not activated */
46 		if (!br_vlan_should_use(v) || !v->tinfo.tunnel_id)
47 			continue;
48 
49 		if (!vtbegin) {
50 			goto initvars;
51 		} else if ((v->vid - vtend->vid) == 1 &&
52 			   vlan_tunid_inrange(v, vtend)) {
53 			vtend = v;
54 			continue;
55 		} else {
56 			if ((vtend->vid - vtbegin->vid) > 0)
57 				num_tinfos += 2;
58 			else
59 				num_tinfos += 1;
60 		}
61 initvars:
62 		vtbegin = v;
63 		vtend = v;
64 	}
65 
66 	if (vtbegin && vtend) {
67 		if ((vtend->vid - vtbegin->vid) > 0)
68 			num_tinfos += 2;
69 		else
70 			num_tinfos += 1;
71 	}
72 
73 	return num_tinfos;
74 }
75 
76 int br_get_vlan_tunnel_info_size(struct net_bridge_vlan_group *vg)
77 {
78 	int num_tinfos;
79 
80 	if (!vg)
81 		return 0;
82 
83 	rcu_read_lock();
84 	num_tinfos = __get_num_vlan_tunnel_infos(vg);
85 	rcu_read_unlock();
86 
87 	return num_tinfos * __get_vlan_tinfo_size();
88 }
89 
90 static int br_fill_vlan_tinfo(struct sk_buff *skb, u16 vid,
91 			      __be64 tunnel_id, u16 flags)
92 {
93 	__be32 tid = tunnel_id_to_key32(tunnel_id);
94 	struct nlattr *tmap;
95 
96 	tmap = nla_nest_start_noflag(skb, IFLA_BRIDGE_VLAN_TUNNEL_INFO);
97 	if (!tmap)
98 		return -EMSGSIZE;
99 	if (nla_put_u32(skb, IFLA_BRIDGE_VLAN_TUNNEL_ID,
100 			be32_to_cpu(tid)))
101 		goto nla_put_failure;
102 	if (nla_put_u16(skb, IFLA_BRIDGE_VLAN_TUNNEL_VID,
103 			vid))
104 		goto nla_put_failure;
105 	if (nla_put_u16(skb, IFLA_BRIDGE_VLAN_TUNNEL_FLAGS,
106 			flags))
107 		goto nla_put_failure;
108 	nla_nest_end(skb, tmap);
109 
110 	return 0;
111 
112 nla_put_failure:
113 	nla_nest_cancel(skb, tmap);
114 
115 	return -EMSGSIZE;
116 }
117 
118 static int br_fill_vlan_tinfo_range(struct sk_buff *skb,
119 				    struct net_bridge_vlan *vtbegin,
120 				    struct net_bridge_vlan *vtend)
121 {
122 	int err;
123 
124 	if (vtend && (vtend->vid - vtbegin->vid) > 0) {
125 		/* add range to skb */
126 		err = br_fill_vlan_tinfo(skb, vtbegin->vid,
127 					 vtbegin->tinfo.tunnel_id,
128 					 BRIDGE_VLAN_INFO_RANGE_BEGIN);
129 		if (err)
130 			return err;
131 
132 		err = br_fill_vlan_tinfo(skb, vtend->vid,
133 					 vtend->tinfo.tunnel_id,
134 					 BRIDGE_VLAN_INFO_RANGE_END);
135 		if (err)
136 			return err;
137 	} else {
138 		err = br_fill_vlan_tinfo(skb, vtbegin->vid,
139 					 vtbegin->tinfo.tunnel_id,
140 					 0);
141 		if (err)
142 			return err;
143 	}
144 
145 	return 0;
146 }
147 
148 int br_fill_vlan_tunnel_info(struct sk_buff *skb,
149 			     struct net_bridge_vlan_group *vg)
150 {
151 	struct net_bridge_vlan *vtbegin = NULL;
152 	struct net_bridge_vlan *vtend = NULL;
153 	struct net_bridge_vlan *v;
154 	int err;
155 
156 	/* Count number of vlan infos */
157 	list_for_each_entry_rcu(v, &vg->vlan_list, vlist) {
158 		/* only a context, bridge vlan not activated */
159 		if (!br_vlan_should_use(v))
160 			continue;
161 
162 		if (!v->tinfo.tunnel_dst)
163 			continue;
164 
165 		if (!vtbegin) {
166 			goto initvars;
167 		} else if ((v->vid - vtend->vid) == 1 &&
168 			    vlan_tunid_inrange(v, vtend)) {
169 			vtend = v;
170 			continue;
171 		} else {
172 			err = br_fill_vlan_tinfo_range(skb, vtbegin, vtend);
173 			if (err)
174 				return err;
175 		}
176 initvars:
177 		vtbegin = v;
178 		vtend = v;
179 	}
180 
181 	if (vtbegin) {
182 		err = br_fill_vlan_tinfo_range(skb, vtbegin, vtend);
183 		if (err)
184 			return err;
185 	}
186 
187 	return 0;
188 }
189 
190 static const struct nla_policy vlan_tunnel_policy[IFLA_BRIDGE_VLAN_TUNNEL_MAX + 1] = {
191 	[IFLA_BRIDGE_VLAN_TUNNEL_ID] = { .type = NLA_U32 },
192 	[IFLA_BRIDGE_VLAN_TUNNEL_VID] = { .type = NLA_U16 },
193 	[IFLA_BRIDGE_VLAN_TUNNEL_FLAGS] = { .type = NLA_U16 },
194 };
195 
196 int br_vlan_tunnel_info(const struct net_bridge_port *p, int cmd,
197 			u16 vid, u32 tun_id, bool *changed)
198 {
199 	int err = 0;
200 
201 	if (!p)
202 		return -EINVAL;
203 
204 	switch (cmd) {
205 	case RTM_SETLINK:
206 		err = nbp_vlan_tunnel_info_add(p, vid, tun_id);
207 		if (!err)
208 			*changed = true;
209 		break;
210 	case RTM_DELLINK:
211 		if (!nbp_vlan_tunnel_info_delete(p, vid))
212 			*changed = true;
213 		break;
214 	}
215 
216 	return err;
217 }
218 
219 int br_parse_vlan_tunnel_info(struct nlattr *attr,
220 			      struct vtunnel_info *tinfo)
221 {
222 	struct nlattr *tb[IFLA_BRIDGE_VLAN_TUNNEL_MAX + 1];
223 	u32 tun_id;
224 	u16 vid, flags = 0;
225 	int err;
226 
227 	memset(tinfo, 0, sizeof(*tinfo));
228 
229 	err = nla_parse_nested_deprecated(tb, IFLA_BRIDGE_VLAN_TUNNEL_MAX,
230 					  attr, vlan_tunnel_policy, NULL);
231 	if (err < 0)
232 		return err;
233 
234 	if (!tb[IFLA_BRIDGE_VLAN_TUNNEL_ID] ||
235 	    !tb[IFLA_BRIDGE_VLAN_TUNNEL_VID])
236 		return -EINVAL;
237 
238 	tun_id = nla_get_u32(tb[IFLA_BRIDGE_VLAN_TUNNEL_ID]);
239 	vid = nla_get_u16(tb[IFLA_BRIDGE_VLAN_TUNNEL_VID]);
240 	if (vid >= VLAN_VID_MASK)
241 		return -ERANGE;
242 
243 	if (tb[IFLA_BRIDGE_VLAN_TUNNEL_FLAGS])
244 		flags = nla_get_u16(tb[IFLA_BRIDGE_VLAN_TUNNEL_FLAGS]);
245 
246 	tinfo->tunid = tun_id;
247 	tinfo->vid = vid;
248 	tinfo->flags = flags;
249 
250 	return 0;
251 }
252 
253 /* send a notification if v_curr can't enter the range and start a new one */
254 static void __vlan_tunnel_handle_range(const struct net_bridge_port *p,
255 				       struct net_bridge_vlan **v_start,
256 				       struct net_bridge_vlan **v_end,
257 				       int v_curr, bool curr_change)
258 {
259 	struct net_bridge_vlan_group *vg;
260 	struct net_bridge_vlan *v;
261 
262 	vg = nbp_vlan_group(p);
263 	if (!vg)
264 		return;
265 
266 	v = br_vlan_find(vg, v_curr);
267 
268 	if (!*v_start)
269 		goto out_init;
270 
271 	if (v && curr_change && br_vlan_can_enter_range(v, *v_end)) {
272 		*v_end = v;
273 		return;
274 	}
275 
276 	br_vlan_notify(p->br, p, (*v_start)->vid, (*v_end)->vid, RTM_NEWVLAN);
277 out_init:
278 	/* we start a range only if there are any changes to notify about */
279 	*v_start = curr_change ? v : NULL;
280 	*v_end = *v_start;
281 }
282 
283 int br_process_vlan_tunnel_info(const struct net_bridge *br,
284 				const struct net_bridge_port *p, int cmd,
285 				struct vtunnel_info *tinfo_curr,
286 				struct vtunnel_info *tinfo_last,
287 				bool *changed)
288 {
289 	int err;
290 
291 	if (tinfo_curr->flags & BRIDGE_VLAN_INFO_RANGE_BEGIN) {
292 		if (tinfo_last->flags & BRIDGE_VLAN_INFO_RANGE_BEGIN)
293 			return -EINVAL;
294 		memcpy(tinfo_last, tinfo_curr, sizeof(struct vtunnel_info));
295 	} else if (tinfo_curr->flags & BRIDGE_VLAN_INFO_RANGE_END) {
296 		struct net_bridge_vlan *v_start = NULL, *v_end = NULL;
297 		int t, v;
298 
299 		if (!(tinfo_last->flags & BRIDGE_VLAN_INFO_RANGE_BEGIN))
300 			return -EINVAL;
301 		if ((tinfo_curr->vid - tinfo_last->vid) !=
302 		    (tinfo_curr->tunid - tinfo_last->tunid))
303 			return -EINVAL;
304 		t = tinfo_last->tunid;
305 		for (v = tinfo_last->vid; v <= tinfo_curr->vid; v++) {
306 			bool curr_change = false;
307 
308 			err = br_vlan_tunnel_info(p, cmd, v, t, &curr_change);
309 			if (err)
310 				break;
311 			t++;
312 
313 			if (curr_change)
314 				*changed = curr_change;
315 			 __vlan_tunnel_handle_range(p, &v_start, &v_end, v,
316 						    curr_change);
317 		}
318 		if (v_start && v_end)
319 			br_vlan_notify(br, p, v_start->vid, v_end->vid,
320 				       RTM_NEWVLAN);
321 		if (err)
322 			return err;
323 
324 		memset(tinfo_last, 0, sizeof(struct vtunnel_info));
325 		memset(tinfo_curr, 0, sizeof(struct vtunnel_info));
326 	} else {
327 		if (tinfo_last->flags)
328 			return -EINVAL;
329 		err = br_vlan_tunnel_info(p, cmd, tinfo_curr->vid,
330 					  tinfo_curr->tunid, changed);
331 		if (err)
332 			return err;
333 		br_vlan_notify(br, p, tinfo_curr->vid, 0, RTM_NEWVLAN);
334 		memset(tinfo_last, 0, sizeof(struct vtunnel_info));
335 		memset(tinfo_curr, 0, sizeof(struct vtunnel_info));
336 	}
337 
338 	return 0;
339 }
340