xref: /openbmc/linux/net/bridge/br_vlan_options.c (revision fa388f29)
1 // SPDX-License-Identifier: GPL-2.0-only
2 // Copyright (c) 2020, Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
3 #include <linux/kernel.h>
4 #include <linux/netdevice.h>
5 #include <linux/rtnetlink.h>
6 #include <linux/slab.h>
7 #include <net/ip_tunnels.h>
8 
9 #include "br_private.h"
10 #include "br_private_tunnel.h"
11 
12 static bool __vlan_tun_put(struct sk_buff *skb, const struct net_bridge_vlan *v)
13 {
14 	__be32 tid = tunnel_id_to_key32(v->tinfo.tunnel_id);
15 	struct nlattr *nest;
16 
17 	if (!v->tinfo.tunnel_dst)
18 		return true;
19 
20 	nest = nla_nest_start(skb, BRIDGE_VLANDB_ENTRY_TUNNEL_INFO);
21 	if (!nest)
22 		return false;
23 	if (nla_put_u32(skb, BRIDGE_VLANDB_TINFO_ID, be32_to_cpu(tid))) {
24 		nla_nest_cancel(skb, nest);
25 		return false;
26 	}
27 	nla_nest_end(skb, nest);
28 
29 	return true;
30 }
31 
32 static bool __vlan_tun_can_enter_range(const struct net_bridge_vlan *v_curr,
33 				       const struct net_bridge_vlan *range_end)
34 {
35 	return (!v_curr->tinfo.tunnel_dst && !range_end->tinfo.tunnel_dst) ||
36 	       vlan_tunid_inrange(v_curr, range_end);
37 }
38 
39 /* check if the options' state of v_curr allow it to enter the range */
40 bool br_vlan_opts_eq_range(const struct net_bridge_vlan *v_curr,
41 			   const struct net_bridge_vlan *range_end)
42 {
43 	return v_curr->state == range_end->state &&
44 	       __vlan_tun_can_enter_range(v_curr, range_end);
45 }
46 
47 bool br_vlan_opts_fill(struct sk_buff *skb, const struct net_bridge_vlan *v)
48 {
49 	return !nla_put_u8(skb, BRIDGE_VLANDB_ENTRY_STATE,
50 			   br_vlan_get_state(v)) &&
51 	       __vlan_tun_put(skb, v);
52 }
53 
54 size_t br_vlan_opts_nl_size(void)
55 {
56 	return nla_total_size(sizeof(u8)) /* BRIDGE_VLANDB_ENTRY_STATE */
57 	       + nla_total_size(0) /* BRIDGE_VLANDB_ENTRY_TUNNEL_INFO */
58 	       + nla_total_size(sizeof(u32)); /* BRIDGE_VLANDB_TINFO_ID */
59 }
60 
61 static int br_vlan_modify_state(struct net_bridge_vlan_group *vg,
62 				struct net_bridge_vlan *v,
63 				u8 state,
64 				bool *changed,
65 				struct netlink_ext_ack *extack)
66 {
67 	struct net_bridge *br;
68 
69 	ASSERT_RTNL();
70 
71 	if (state > BR_STATE_BLOCKING) {
72 		NL_SET_ERR_MSG_MOD(extack, "Invalid vlan state");
73 		return -EINVAL;
74 	}
75 
76 	if (br_vlan_is_brentry(v))
77 		br = v->br;
78 	else
79 		br = v->port->br;
80 
81 	if (br->stp_enabled == BR_KERNEL_STP) {
82 		NL_SET_ERR_MSG_MOD(extack, "Can't modify vlan state when using kernel STP");
83 		return -EBUSY;
84 	}
85 
86 	if (v->state == state)
87 		return 0;
88 
89 	if (v->vid == br_get_pvid(vg))
90 		br_vlan_set_pvid_state(vg, state);
91 
92 	br_vlan_set_state(v, state);
93 	*changed = true;
94 
95 	return 0;
96 }
97 
98 static const struct nla_policy br_vlandb_tinfo_pol[BRIDGE_VLANDB_TINFO_MAX + 1] = {
99 	[BRIDGE_VLANDB_TINFO_ID]	= { .type = NLA_U32 },
100 };
101 
102 static int br_vlan_modify_tunnel(const struct net_bridge_port *p,
103 				 struct net_bridge_vlan *v,
104 				 struct nlattr **tb,
105 				 bool *changed,
106 				 struct netlink_ext_ack *extack)
107 {
108 	struct nlattr *tun_tb[BRIDGE_VLANDB_TINFO_MAX + 1], *attr;
109 	struct bridge_vlan_info *vinfo;
110 	int cmdmap, err;
111 	u32 tun_id;
112 
113 	if (!p) {
114 		NL_SET_ERR_MSG_MOD(extack, "Can't modify tunnel mapping of non-port vlans");
115 		return -EINVAL;
116 	}
117 	if (!(p->flags & BR_VLAN_TUNNEL)) {
118 		NL_SET_ERR_MSG_MOD(extack, "Port doesn't have tunnel flag set");
119 		return -EINVAL;
120 	}
121 
122 	attr = tb[BRIDGE_VLANDB_ENTRY_TUNNEL_INFO];
123 	err = nla_parse_nested(tun_tb, BRIDGE_VLANDB_TINFO_MAX, attr,
124 			       br_vlandb_tinfo_pol, extack);
125 	if (err)
126 		return err;
127 
128 	if (!tun_tb[BRIDGE_VLANDB_TINFO_ID]) {
129 		NL_SET_ERR_MSG_MOD(extack, "Missing tunnel id attribute");
130 		return -ENOENT;
131 	}
132 	/* vlan info attribute is guaranteed by br_vlan_rtm_process_one */
133 	vinfo = nla_data(tb[BRIDGE_VLANDB_ENTRY_INFO]);
134 	cmdmap = vinfo->flags & BRIDGE_VLAN_INFO_REMOVE_TUN ? RTM_DELLINK :
135 							      RTM_SETLINK;
136 	/* when working on vlan ranges this represents the starting tunnel id */
137 	tun_id = nla_get_u32(tun_tb[BRIDGE_VLANDB_TINFO_ID]);
138 	/* tunnel ids are mapped to each vlan in increasing order,
139 	 * the starting vlan is in BRIDGE_VLANDB_ENTRY_INFO and v is the
140 	 * current vlan, so we compute: tun_id + v - vinfo->vid
141 	 */
142 	tun_id += v->vid - vinfo->vid;
143 
144 	return br_vlan_tunnel_info(p, cmdmap, v->vid, tun_id, changed);
145 }
146 
147 static int br_vlan_process_one_opts(const struct net_bridge *br,
148 				    const struct net_bridge_port *p,
149 				    struct net_bridge_vlan_group *vg,
150 				    struct net_bridge_vlan *v,
151 				    struct nlattr **tb,
152 				    bool *changed,
153 				    struct netlink_ext_ack *extack)
154 {
155 	int err;
156 
157 	*changed = false;
158 	if (tb[BRIDGE_VLANDB_ENTRY_STATE]) {
159 		u8 state = nla_get_u8(tb[BRIDGE_VLANDB_ENTRY_STATE]);
160 
161 		err = br_vlan_modify_state(vg, v, state, changed, extack);
162 		if (err)
163 			return err;
164 	}
165 	if (tb[BRIDGE_VLANDB_ENTRY_TUNNEL_INFO]) {
166 		err = br_vlan_modify_tunnel(p, v, tb, changed, extack);
167 		if (err)
168 			return err;
169 	}
170 
171 	return 0;
172 }
173 
174 int br_vlan_process_options(const struct net_bridge *br,
175 			    const struct net_bridge_port *p,
176 			    struct net_bridge_vlan *range_start,
177 			    struct net_bridge_vlan *range_end,
178 			    struct nlattr **tb,
179 			    struct netlink_ext_ack *extack)
180 {
181 	struct net_bridge_vlan *v, *curr_start = NULL, *curr_end = NULL;
182 	struct net_bridge_vlan_group *vg;
183 	int vid, err = 0;
184 	u16 pvid;
185 
186 	if (p)
187 		vg = nbp_vlan_group(p);
188 	else
189 		vg = br_vlan_group(br);
190 
191 	if (!range_start || !br_vlan_should_use(range_start)) {
192 		NL_SET_ERR_MSG_MOD(extack, "Vlan range start doesn't exist, can't process options");
193 		return -ENOENT;
194 	}
195 	if (!range_end || !br_vlan_should_use(range_end)) {
196 		NL_SET_ERR_MSG_MOD(extack, "Vlan range end doesn't exist, can't process options");
197 		return -ENOENT;
198 	}
199 
200 	pvid = br_get_pvid(vg);
201 	for (vid = range_start->vid; vid <= range_end->vid; vid++) {
202 		bool changed = false;
203 
204 		v = br_vlan_find(vg, vid);
205 		if (!v || !br_vlan_should_use(v)) {
206 			NL_SET_ERR_MSG_MOD(extack, "Vlan in range doesn't exist, can't process options");
207 			err = -ENOENT;
208 			break;
209 		}
210 
211 		err = br_vlan_process_one_opts(br, p, vg, v, tb, &changed,
212 					       extack);
213 		if (err)
214 			break;
215 
216 		if (changed) {
217 			/* vlan options changed, check for range */
218 			if (!curr_start) {
219 				curr_start = v;
220 				curr_end = v;
221 				continue;
222 			}
223 
224 			if (v->vid == pvid ||
225 			    !br_vlan_can_enter_range(v, curr_end)) {
226 				br_vlan_notify(br, p, curr_start->vid,
227 					       curr_end->vid, RTM_NEWVLAN);
228 				curr_start = v;
229 			}
230 			curr_end = v;
231 		} else {
232 			/* nothing changed and nothing to notify yet */
233 			if (!curr_start)
234 				continue;
235 
236 			br_vlan_notify(br, p, curr_start->vid, curr_end->vid,
237 				       RTM_NEWVLAN);
238 			curr_start = NULL;
239 			curr_end = NULL;
240 		}
241 	}
242 	if (curr_start)
243 		br_vlan_notify(br, p, curr_start->vid, curr_end->vid,
244 			       RTM_NEWVLAN);
245 
246 	return err;
247 }
248