src/network/networkd-ipv4ll.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2
   3 #include <netinet/in.h>
   4 #include <linux/if.h>
   5
   6 #include "network-internal.h"
   7 #include "networkd-address.h"
   8 #include "networkd-ipv4ll.h"
   9 #include "networkd-link.h"
  10 #include "networkd-manager.h"
  11 #include "parse-util.h"
  12
  13 static int ipv4ll_address_lost(Link *link) {
  14         _cleanup_(address_freep) Address *address = NULL;
  15         struct in_addr addr;
  16         int r;
  17
  18         assert(link);
  19
  20         link->ipv4ll_address = false;
  21
  22         r = sd_ipv4ll_get_address(link->ipv4ll, &addr);
  23         if (r < 0)
  24                 return 0;
  25
  26         log_link_debug(link, "IPv4 link-local release %u.%u.%u.%u", ADDRESS_FMT_VAL(addr));
  27
  28         r = address_new(&address);
  29         if (r < 0)
  30                 return log_link_error_errno(link, r, "Could not allocate address: %m");
  31
  32         address->family = AF_INET;
  33         address->in_addr.in = addr;
  34         address->prefixlen = 16;
  35         address->scope = RT_SCOPE_LINK;
  36
  37         r = address_remove(address, link, NULL);
  38         if (r < 0)
  39                 return r;
  40
  41         link_check_ready(link);
  42
  43         return 0;
  44 }
  45
  46 static int ipv4ll_address_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
  47         int r;
  48
  49         assert(link);
  50         assert(!link->ipv4ll_address);
  51
  52         r = sd_netlink_message_get_errno(m);
  53         if (r < 0 && r != -EEXIST) {
  54                 log_link_message_warning_errno(link, m, r, "could not set ipv4ll address");
  55                 link_enter_failed(link);
  56                 return 1;
  57         } else if (r >= 0)
  58                 (void) manager_rtnl_process_address(rtnl, m, link->manager);
  59
  60         link->ipv4ll_address = true;
  61         link_check_ready(link);
  62
  63         return 1;
  64 }
  65
  66 static int ipv4ll_address_claimed(sd_ipv4ll *ll, Link *link) {
  67         _cleanup_(address_freep) Address *ll_addr = NULL;
  68         struct in_addr address;
  69         int r;
  70
  71         assert(ll);
  72         assert(link);
  73
  74         link->ipv4ll_address = false;
  75
  76         r = sd_ipv4ll_get_address(ll, &address);
  77         if (r == -ENOENT)
  78                 return 0;
  79         else if (r < 0)
  80                 return r;
  81
  82         log_link_debug(link, "IPv4 link-local claim %u.%u.%u.%u",
  83                        ADDRESS_FMT_VAL(address));
  84
  85         r = address_new(&ll_addr);
  86         if (r < 0)
  87                 return r;
  88
  89         ll_addr->family = AF_INET;
  90         ll_addr->in_addr.in = address;
  91         ll_addr->prefixlen = 16;
  92         ll_addr->broadcast.s_addr = ll_addr->in_addr.in.s_addr | htobe32(0xfffffffflu >> ll_addr->prefixlen);
  93         ll_addr->scope = RT_SCOPE_LINK;
  94
  95         r = address_configure(ll_addr, link, ipv4ll_address_handler, false, NULL);
  96         if (r < 0)
  97                 return r;
  98
  99         return 0;
 100 }
 101
 102 static void ipv4ll_handler(sd_ipv4ll *ll, int event, void *userdata) {
 103         Link *link = userdata;
 104         int r;
 105
 106         assert(link);
 107         assert(link->network);
 108
 109         if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER))
 110                 return;
 111
 112         switch(event) {
 113                 case SD_IPV4LL_EVENT_STOP:
 114                         r = ipv4ll_address_lost(link);
 115                         if (r < 0) {
 116                                 link_enter_failed(link);
 117                                 return;
 118                         }
 119                         break;
 120                 case SD_IPV4LL_EVENT_CONFLICT:
 121                         r = ipv4ll_address_lost(link);
 122                         if (r < 0) {
 123                                 link_enter_failed(link);
 124                                 return;
 125                         }
 126
 127                         r = sd_ipv4ll_restart(ll);
 128                         if (r < 0)
 129                                 log_link_warning_errno(link, r, "Could not acquire IPv4 link-local address: %m");
 130                         break;
 131                 case SD_IPV4LL_EVENT_BIND:
 132                         r = ipv4ll_address_claimed(ll, link);
 133                         if (r < 0) {
 134                                 log_link_error(link, "Failed to configure ipv4ll address: %m");
 135                                 link_enter_failed(link);
 136                                 return;
 137                         }
 138                         break;
 139                 default:
 140                         log_link_warning(link, "IPv4 link-local unknown event: %d", event);
 141                         break;
 142         }
 143 }
 144
 145 int ipv4ll_configure(Link *link) {
 146         uint64_t seed;
 147         int r;
 148
 149         assert(link);
 150         assert(link->network);
 151         assert(link->network->link_local & (ADDRESS_FAMILY_IPV4 | ADDRESS_FAMILY_FALLBACK_IPV4));
 152
 153         if (!link->ipv4ll) {
 154                 r = sd_ipv4ll_new(&link->ipv4ll);
 155                 if (r < 0)
 156                         return r;
 157
 158                 r = sd_ipv4ll_attach_event(link->ipv4ll, NULL, 0);
 159                 if (r < 0)
 160                         return r;
 161         }
 162
 163         if (link->sd_device &&
 164             net_get_unique_predictable_data(link->sd_device, true, &seed) >= 0) {
 165                 r = sd_ipv4ll_set_address_seed(link->ipv4ll, seed);
 166                 if (r < 0)
 167                         return r;
 168         }
 169
 170         r = sd_ipv4ll_set_mac(link->ipv4ll, &link->mac);
 171         if (r < 0)
 172                 return r;
 173
 174         r = sd_ipv4ll_set_ifindex(link->ipv4ll, link->ifindex);
 175         if (r < 0)
 176                 return r;
 177
 178         r = sd_ipv4ll_set_callback(link->ipv4ll, ipv4ll_handler, link);
 179         if (r < 0)
 180                 return r;
 181
 182         return 0;
 183 }
 184
 185 int config_parse_ipv4ll(
 186                 const char* unit,
 187                 const char *filename,
 188                 unsigned line,
 189                 const char *section,
 190                 unsigned section_line,
 191                 const char *lvalue,
 192                 int ltype,
 193                 const char *rvalue,
 194                 void *data,
 195                 void *userdata) {
 196
 197         AddressFamily *link_local = data;
 198         int r;
 199
 200         assert(filename);
 201         assert(lvalue);
 202         assert(rvalue);
 203         assert(data);
 204
 205         /* Note that this is mostly like
 206          * config_parse_address_family(), except that it
 207          * applies only to IPv4 */
 208
 209         r = parse_boolean(rvalue);
 210         if (r < 0) {
 211                 log_syntax(unit, LOG_WARNING, filename, line, r,
 212                            "Failed to parse %s=%s, ignoring assignment. "
 213                            "Note that the setting %s= is deprecated, please use LinkLocalAddressing= instead.",
 214                            lvalue, rvalue, lvalue);
 215                 return 0;
 216         }
 217
 218         SET_FLAG(*link_local, ADDRESS_FAMILY_IPV4, r);
 219
 220         log_syntax(unit, LOG_WARNING, filename, line, 0,
 221                    "%s=%s is deprecated, please use LinkLocalAddressing=%s instead.",
 222                    lvalue, rvalue, address_family_to_string(*link_local));
 223
 224         return 0;
 225 }