src/network/networkd-radv.c

   1 /***
   2   This file is part of systemd.
   3
   4   Copyright (C) 2017 Intel Corporation. All rights reserved.
   5
   6   systemd is free software; you can redistribute it and/or modify it
   7   under the terms of the GNU Lesser General Public License as published by
   8   the Free Software Foundation; either version 2.1 of the License, or
   9   (at your option) any later version.
  10
  11   systemd is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   Lesser General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public License
  17   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  18 ***/
  19
  20 #include <netinet/icmp6.h>
  21 #include <arpa/inet.h>
  22
  23 #include "networkd-address.h"
  24 #include "networkd-manager.h"
  25 #include "networkd-radv.h"
  26 #include "sd-radv.h"
  27
  28 static int radv_get_ip6dns(Network *network, struct in6_addr **dns,
  29                            size_t *n_dns) {
  30         _cleanup_free_ struct in6_addr *addresses = NULL;
  31         size_t i, n_addresses = 0, n_allocated = 0;
  32
  33         assert(network);
  34         assert(dns);
  35         assert(n_dns);
  36
  37         for (i = 0; i < network->n_dns; i++) {
  38                 union in_addr_union *addr;
  39
  40                 if (network->dns[i].family != AF_INET6)
  41                         continue;
  42
  43                 addr = &network->dns[i].address;
  44
  45                 if (in_addr_is_null(AF_INET6, addr) ||
  46                     in_addr_is_link_local(AF_INET6, addr) ||
  47                     in_addr_is_localhost(AF_INET6, addr))
  48                         continue;
  49
  50                 if (!GREEDY_REALLOC(addresses, n_allocated, n_addresses + 1))
  51                         return -ENOMEM;
  52
  53                 addresses[n_addresses++] = addr->in6;
  54         }
  55
  56         if (addresses) {
  57                 *dns = addresses;
  58                 addresses = NULL;
  59
  60                 *n_dns = n_addresses;
  61         }
  62
  63         return n_addresses;
  64 }
  65
  66 static int radv_set_dns(Link *link, Link *uplink) {
  67         _cleanup_free_ struct in6_addr *dns = NULL;
  68         size_t n_dns;
  69         usec_t lifetime_usec;
  70         int r;
  71
  72         if (!link->network->router_emit_dns)
  73                 return 0;
  74
  75         if (link->network->router_dns) {
  76                 dns = newdup(struct in6_addr, link->network->router_dns,
  77                              link->network->n_router_dns);
  78                 if (dns == NULL)
  79                         return -ENOMEM;
  80
  81                 n_dns = link->network->n_router_dns;
  82                 lifetime_usec = link->network->router_dns_lifetime_usec;
  83
  84                 goto set_dns;
  85         }
  86
  87         lifetime_usec = SD_RADV_DEFAULT_DNS_LIFETIME_USEC;
  88
  89         r = radv_get_ip6dns(link->network, &dns, &n_dns);
  90         if (r > 0)
  91                 goto set_dns;
  92
  93         if (uplink) {
  94                 r = radv_get_ip6dns(uplink->network, &dns, &n_dns);
  95                 if (r > 0)
  96                         goto set_dns;
  97         }
  98
  99         return 0;
 100
 101  set_dns:
 102         return sd_radv_set_rdnss(link->radv,
 103                                  DIV_ROUND_UP(lifetime_usec, USEC_PER_SEC),
 104                                  dns, n_dns);
 105 }
 106
 107 static int radv_set_domains(Link *link, Link *uplink) {
 108         char **search_domains;
 109         usec_t lifetime_usec;
 110
 111         if (!link->network->router_emit_domains)
 112                 return 0;
 113
 114         search_domains = link->network->router_search_domains;
 115         lifetime_usec = link->network->router_dns_lifetime_usec;
 116
 117         if (search_domains)
 118                 goto set_domains;
 119
 120         lifetime_usec = SD_RADV_DEFAULT_DNS_LIFETIME_USEC;
 121
 122         search_domains = link->network->search_domains;
 123         if (search_domains)
 124                 goto set_domains;
 125
 126         if (uplink) {
 127                 search_domains = uplink->network->search_domains;
 128                 if (search_domains)
 129                         goto set_domains;
 130         }
 131
 132         return 0;
 133
 134  set_domains:
 135         return sd_radv_set_dnssl(link->radv,
 136                                  DIV_ROUND_UP(lifetime_usec, USEC_PER_SEC),
 137                                  search_domains);
 138
 139 }
 140
 141 int radv_emit_dns(Link *link) {
 142         Link *uplink;
 143         int r;
 144
 145         uplink = manager_find_uplink(link->manager, link);
 146
 147         r = radv_set_dns(link, uplink);
 148         if (r < 0)
 149                 log_link_warning_errno(link, r, "Could not set RA DNS: %m");
 150
 151         r = radv_set_domains(link, uplink);
 152         if (r < 0)
 153                 log_link_warning_errno(link, r, "Could not set RA Domains: %m");
 154
 155         return 0;
 156 }
 157
 158 int radv_configure(Link *link) {
 159         int r;
 160         Prefix *p;
 161
 162         assert(link);
 163         assert(link->network);
 164
 165         r = sd_radv_new(&link->radv);
 166         if (r < 0)
 167                 return r;
 168
 169         r = sd_radv_attach_event(link->radv, NULL, 0);
 170         if (r < 0)
 171                 return r;
 172
 173         r = sd_radv_set_mac(link->radv, &link->mac);
 174         if (r < 0)
 175                 return r;
 176
 177         r = sd_radv_set_ifindex(link->radv, link->ifindex);
 178         if (r < 0)
 179                 return r;
 180
 181         r = sd_radv_set_managed_information(link->radv, link->network->router_managed);
 182         if (r < 0)
 183                 return r;
 184
 185         r = sd_radv_set_other_information(link->radv, link->network->router_other_information);
 186         if (r < 0)
 187                 return r;
 188
 189         /* a value of 0xffffffff represents infinity, 0x0 means this host is
 190            not a router */
 191         r = sd_radv_set_router_lifetime(link->radv,
 192                                         DIV_ROUND_UP(link->network->router_lifetime_usec, USEC_PER_SEC));
 193         if (r < 0)
 194                 return r;
 195
 196         if (link->network->router_lifetime_usec > 0) {
 197                 r = sd_radv_set_preference(link->radv,
 198                                            link->network->router_preference);
 199                 if (r < 0)
 200                         return r;
 201         }
 202
 203         LIST_FOREACH(prefixes, p, link->network->static_prefixes) {
 204                 r = sd_radv_add_prefix(link->radv, p->radv_prefix);
 205                 if (r != -EEXIST && r < 0)
 206                         return r;
 207         }
 208
 209         return radv_emit_dns(link);
 210 }