Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * net/l3mdev/l3mdev.c - L3 master device implementation
4 * Copyright (c) 2015 Cumulus Networks
5 * Copyright (c) 2015 David Ahern <dsa@cumulusnetworks.com>
6 */
7
8#include <linux/netdevice.h>
9#include <net/fib_rules.h>
10#include <net/l3mdev.h>
11
12/**
13 * l3mdev_master_ifindex - get index of L3 master device
14 * @dev: targeted interface
15 */
16
17int l3mdev_master_ifindex_rcu(const struct net_device *dev)
18{
19 int ifindex = 0;
20
21 if (!dev)
22 return 0;
23
24 if (netif_is_l3_master(dev)) {
25 ifindex = dev->ifindex;
26 } else if (netif_is_l3_slave(dev)) {
27 struct net_device *master;
28 struct net_device *_dev = (struct net_device *)dev;
29
30 /* netdev_master_upper_dev_get_rcu calls
31 * list_first_or_null_rcu to walk the upper dev list.
32 * list_first_or_null_rcu does not handle a const arg. We aren't
33 * making changes, just want the master device from that list so
34 * typecast to remove the const
35 */
36 master = netdev_master_upper_dev_get_rcu(_dev);
37 if (master)
38 ifindex = master->ifindex;
39 }
40
41 return ifindex;
42}
43EXPORT_SYMBOL_GPL(l3mdev_master_ifindex_rcu);
44
45/**
46 * l3mdev_master_upper_ifindex_by_index - get index of upper l3 master
47 * device
48 * @net: network namespace for device index lookup
49 * @ifindex: targeted interface
50 */
51int l3mdev_master_upper_ifindex_by_index_rcu(struct net *net, int ifindex)
52{
53 struct net_device *dev;
54
55 dev = dev_get_by_index_rcu(net, ifindex);
56 while (dev && !netif_is_l3_master(dev))
57 dev = netdev_master_upper_dev_get(dev);
58
59 return dev ? dev->ifindex : 0;
60}
61EXPORT_SYMBOL_GPL(l3mdev_master_upper_ifindex_by_index_rcu);
62
63/**
64 * l3mdev_fib_table - get FIB table id associated with an L3
65 * master interface
66 * @dev: targeted interface
67 */
68
69u32 l3mdev_fib_table_rcu(const struct net_device *dev)
70{
71 u32 tb_id = 0;
72
73 if (!dev)
74 return 0;
75
76 if (netif_is_l3_master(dev)) {
77 if (dev->l3mdev_ops->l3mdev_fib_table)
78 tb_id = dev->l3mdev_ops->l3mdev_fib_table(dev);
79 } else if (netif_is_l3_slave(dev)) {
80 /* Users of netdev_master_upper_dev_get_rcu need non-const,
81 * but current inet_*type functions take a const
82 */
83 struct net_device *_dev = (struct net_device *) dev;
84 const struct net_device *master;
85
86 master = netdev_master_upper_dev_get_rcu(_dev);
87 if (master &&
88 master->l3mdev_ops->l3mdev_fib_table)
89 tb_id = master->l3mdev_ops->l3mdev_fib_table(master);
90 }
91
92 return tb_id;
93}
94EXPORT_SYMBOL_GPL(l3mdev_fib_table_rcu);
95
96u32 l3mdev_fib_table_by_index(struct net *net, int ifindex)
97{
98 struct net_device *dev;
99 u32 tb_id = 0;
100
101 if (!ifindex)
102 return 0;
103
104 rcu_read_lock();
105
106 dev = dev_get_by_index_rcu(net, ifindex);
107 if (dev)
108 tb_id = l3mdev_fib_table_rcu(dev);
109
110 rcu_read_unlock();
111
112 return tb_id;
113}
114EXPORT_SYMBOL_GPL(l3mdev_fib_table_by_index);
115
116/**
117 * l3mdev_link_scope_lookup - IPv6 route lookup based on flow for link
118 * local and multicast addresses
119 * @net: network namespace for device index lookup
120 * @fl6: IPv6 flow struct for lookup
121 */
122
123struct dst_entry *l3mdev_link_scope_lookup(struct net *net,
124 struct flowi6 *fl6)
125{
126 struct dst_entry *dst = NULL;
127 struct net_device *dev;
128
129 if (fl6->flowi6_oif) {
130 rcu_read_lock();
131
132 dev = dev_get_by_index_rcu(net, fl6->flowi6_oif);
133 if (dev && netif_is_l3_slave(dev))
134 dev = netdev_master_upper_dev_get_rcu(dev);
135
136 if (dev && netif_is_l3_master(dev) &&
137 dev->l3mdev_ops->l3mdev_link_scope_lookup)
138 dst = dev->l3mdev_ops->l3mdev_link_scope_lookup(dev, fl6);
139
140 rcu_read_unlock();
141 }
142
143 return dst;
144}
145EXPORT_SYMBOL_GPL(l3mdev_link_scope_lookup);
146
147/**
148 * l3mdev_fib_rule_match - Determine if flowi references an
149 * L3 master device
150 * @net: network namespace for device index lookup
151 * @fl: flow struct
152 */
153
154int l3mdev_fib_rule_match(struct net *net, struct flowi *fl,
155 struct fib_lookup_arg *arg)
156{
157 struct net_device *dev;
158 int rc = 0;
159
160 rcu_read_lock();
161
162 dev = dev_get_by_index_rcu(net, fl->flowi_oif);
163 if (dev && netif_is_l3_master(dev) &&
164 dev->l3mdev_ops->l3mdev_fib_table) {
165 arg->table = dev->l3mdev_ops->l3mdev_fib_table(dev);
166 rc = 1;
167 goto out;
168 }
169
170 dev = dev_get_by_index_rcu(net, fl->flowi_iif);
171 if (dev && netif_is_l3_master(dev) &&
172 dev->l3mdev_ops->l3mdev_fib_table) {
173 arg->table = dev->l3mdev_ops->l3mdev_fib_table(dev);
174 rc = 1;
175 goto out;
176 }
177
178out:
179 rcu_read_unlock();
180
181 return rc;
182}
183
184void l3mdev_update_flow(struct net *net, struct flowi *fl)
185{
186 struct net_device *dev;
187 int ifindex;
188
189 rcu_read_lock();
190
191 if (fl->flowi_oif) {
192 dev = dev_get_by_index_rcu(net, fl->flowi_oif);
193 if (dev) {
194 ifindex = l3mdev_master_ifindex_rcu(dev);
195 if (ifindex) {
196 fl->flowi_oif = ifindex;
197 fl->flowi_flags |= FLOWI_FLAG_SKIP_NH_OIF;
198 goto out;
199 }
200 }
201 }
202
203 if (fl->flowi_iif) {
204 dev = dev_get_by_index_rcu(net, fl->flowi_iif);
205 if (dev) {
206 ifindex = l3mdev_master_ifindex_rcu(dev);
207 if (ifindex) {
208 fl->flowi_iif = ifindex;
209 fl->flowi_flags |= FLOWI_FLAG_SKIP_NH_OIF;
210 }
211 }
212 }
213
214out:
215 rcu_read_unlock();
216}
217EXPORT_SYMBOL_GPL(l3mdev_update_flow);