1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
|
/* SPDX-License-Identifier: LGPL-2.1-or-later */
#include <netinet/in.h>
#include <linux/if.h>
#include "missing_network.h"
#include "networkd-link.h"
#include "networkd-network.h"
#include "networkd-sysctl.h"
#include "socket-util.h"
#include "string-table.h"
#include "sysctl-util.h"
static int link_update_ipv6_sysctl(Link *link) {
assert(link);
if (link->flags & IFF_LOOPBACK)
return 0;
if (!link_ipv6_enabled(link))
return 0;
return sysctl_write_ip_property_boolean(AF_INET6, link->ifname, "disable_ipv6", false);
}
static int link_set_proxy_arp(Link *link) {
assert(link);
if (link->flags & IFF_LOOPBACK)
return 0;
if (!link->network)
return 0;
if (link->network->proxy_arp < 0)
return 0;
return sysctl_write_ip_property_boolean(AF_INET, link->ifname, "proxy_arp", link->network->proxy_arp > 0);
}
static bool link_ip_forward_enabled(Link *link, int family) {
assert(link);
assert(IN_SET(family, AF_INET, AF_INET6));
if (family == AF_INET6 && !socket_ipv6_is_supported())
return false;
if (link->flags & IFF_LOOPBACK)
return false;
if (!link->network)
return false;
return link->network->ip_forward & (family == AF_INET ? ADDRESS_FAMILY_IPV4 : ADDRESS_FAMILY_IPV6);
}
static int link_set_ipv4_forward(Link *link) {
assert(link);
if (!link_ip_forward_enabled(link, AF_INET))
return 0;
/* We propagate the forwarding flag from one interface to the
* global setting one way. This means: as long as at least one
* interface was configured at any time that had IP forwarding
* enabled the setting will stay on for good. We do this
* primarily to keep IPv4 and IPv6 packet forwarding behaviour
* somewhat in sync (see below). */
return sysctl_write_ip_property(AF_INET, NULL, "ip_forward", "1");
}
static int link_set_ipv6_forward(Link *link) {
assert(link);
if (!link_ip_forward_enabled(link, AF_INET6))
return 0;
/* On Linux, the IPv6 stack does not know a per-interface
* packet forwarding setting: either packet forwarding is on
* for all, or off for all. We hence don't bother with a
* per-interface setting, but simply propagate the interface
* flag, if it is set, to the global flag, one-way. Note that
* while IPv4 would allow a per-interface flag, we expose the
* same behaviour there and also propagate the setting from
* one to all, to keep things simple (see above). */
return sysctl_write_ip_property(AF_INET6, "all", "forwarding", "1");
}
static int link_set_ipv6_privacy_extensions(Link *link) {
assert(link);
if (!socket_ipv6_is_supported())
return 0;
if (link->flags & IFF_LOOPBACK)
return 0;
if (!link->network)
return 0;
// this is the special "kernel" value
if (link->network->ipv6_privacy_extensions == _IPV6_PRIVACY_EXTENSIONS_INVALID)
return 0;
return sysctl_write_ip_property_int(AF_INET6, link->ifname, "use_tempaddr", (int) link->network->ipv6_privacy_extensions);
}
static int link_set_ipv6_accept_ra(Link *link) {
assert(link);
/* Make this a NOP if IPv6 is not available */
if (!socket_ipv6_is_supported())
return 0;
if (link->flags & IFF_LOOPBACK)
return 0;
if (!link->network)
return 0;
return sysctl_write_ip_property(AF_INET6, link->ifname, "accept_ra", "0");
}
static int link_set_ipv6_dad_transmits(Link *link) {
assert(link);
/* Make this a NOP if IPv6 is not available */
if (!socket_ipv6_is_supported())
return 0;
if (link->flags & IFF_LOOPBACK)
return 0;
if (!link->network)
return 0;
if (link->network->ipv6_dad_transmits < 0)
return 0;
return sysctl_write_ip_property_int(AF_INET6, link->ifname, "dad_transmits", link->network->ipv6_dad_transmits);
}
static int link_set_ipv6_hop_limit(Link *link) {
assert(link);
/* Make this a NOP if IPv6 is not available */
if (!socket_ipv6_is_supported())
return 0;
if (link->flags & IFF_LOOPBACK)
return 0;
if (!link->network)
return 0;
if (link->network->ipv6_hop_limit < 0)
return 0;
return sysctl_write_ip_property_int(AF_INET6, link->ifname, "hop_limit", link->network->ipv6_hop_limit);
}
static int link_set_ipv4_accept_local(Link *link) {
assert(link);
if (link->flags & IFF_LOOPBACK)
return 0;
if (link->network->ipv4_accept_local < 0)
return 0;
return sysctl_write_ip_property_boolean(AF_INET, link->ifname, "accept_local", link->network->ipv4_accept_local > 0);
}
int link_set_sysctl(Link *link) {
int r;
assert(link);
/* If IPv6 configured that is static IPv6 address and IPv6LL autoconfiguration is enabled
* for this interface, then enable IPv6 */
r = link_update_ipv6_sysctl(link);
if (r < 0)
log_link_warning_errno(link, r, "Cannot enable IPv6, ignoring: %m");
r = link_set_proxy_arp(link);
if (r < 0)
log_link_warning_errno(link, r, "Cannot configure proxy ARP for interface, ignoring: %m");
r = link_set_ipv4_forward(link);
if (r < 0)
log_link_warning_errno(link, r, "Cannot turn on IPv4 packet forwarding, ignoring: %m");
r = link_set_ipv6_forward(link);
if (r < 0)
log_link_warning_errno(link, r, "Cannot configure IPv6 packet forwarding, ignoring: %m");;
r = link_set_ipv6_privacy_extensions(link);
if (r < 0)
log_link_warning_errno(link, r, "Cannot configure IPv6 privacy extensions for interface, ignoring: %m");
r = link_set_ipv6_accept_ra(link);
if (r < 0)
log_link_warning_errno(link, r, "Cannot disable kernel IPv6 accept_ra for interface, ignoring: %m");
r = link_set_ipv6_dad_transmits(link);
if (r < 0)
log_link_warning_errno(link, r, "Cannot set IPv6 dad transmits for interface, ignoring: %m");
r = link_set_ipv6_hop_limit(link);
if (r < 0)
log_link_warning_errno(link, r, "Cannot set IPv6 hop limit for interface, ignoring: %m");
r = link_set_ipv4_accept_local(link);
if (r < 0)
log_link_warning_errno(link, r, "Cannot set IPv4 accept_local flag for interface, ignoring: %m");
return 0;
}
int link_set_ipv6_mtu(Link *link) {
int r;
assert(link);
/* Make this a NOP if IPv6 is not available */
if (!socket_ipv6_is_supported())
return 0;
if (link->flags & IFF_LOOPBACK)
return 0;
if (link->network->ipv6_mtu == 0)
return 0;
r = sysctl_write_ip_property_uint32(AF_INET6, link->ifname, "mtu", link->network->ipv6_mtu);
if (r < 0)
return r;
link->ipv6_mtu_set = true;
return 0;
}
static const char* const ipv6_privacy_extensions_table[_IPV6_PRIVACY_EXTENSIONS_MAX] = {
[IPV6_PRIVACY_EXTENSIONS_NO] = "no",
[IPV6_PRIVACY_EXTENSIONS_PREFER_PUBLIC] = "prefer-public",
[IPV6_PRIVACY_EXTENSIONS_YES] = "yes",
};
DEFINE_STRING_TABLE_LOOKUP_WITH_BOOLEAN(ipv6_privacy_extensions, IPv6PrivacyExtensions,
IPV6_PRIVACY_EXTENSIONS_YES);
int config_parse_ipv6_privacy_extensions(
const char* unit,
const char *filename,
unsigned line,
const char *section,
unsigned section_line,
const char *lvalue,
int ltype,
const char *rvalue,
void *data,
void *userdata) {
IPv6PrivacyExtensions s, *ipv6_privacy_extensions = data;
assert(filename);
assert(lvalue);
assert(rvalue);
assert(ipv6_privacy_extensions);
s = ipv6_privacy_extensions_from_string(rvalue);
if (s < 0) {
if (streq(rvalue, "kernel"))
s = _IPV6_PRIVACY_EXTENSIONS_INVALID;
else {
log_syntax(unit, LOG_WARNING, filename, line, 0,
"Failed to parse IPv6 privacy extensions option, ignoring: %s", rvalue);
return 0;
}
}
*ipv6_privacy_extensions = s;
return 0;
}
|
