mirror of
https://git.kernel.org/pub/scm/network/wireless/iwd.git
synced 2024-12-22 21:22:37 +01:00
netconfig: Rework IPv4 address handling
Introduce a new v4_address member which will hold the currently configured IPV4 address (static or obtained via DHCP). Use the new l_rtnl_address class for this. As a side-effect, lease expiration will now properly remove the configured address.
This commit is contained in:
Denis Kenzior
parent
eb151efc81
commit
6f5ec005e9
375
src/netconfig.c
375
src/netconfig.c
@ -55,6 +55,7 @@ struct netconfig {
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struct l_queue *ifaddr_list;
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uint8_t rtm_protocol;
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uint8_t rtm_v6_protocol;
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struct l_rtnl_address *v4_address;
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char **dns4_overrides;
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char **dns6_overrides;
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@ -281,88 +282,54 @@ static int netconfig_set_domains(struct netconfig *netconfig)
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return 0;
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}
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static struct netconfig_ifaddr *netconfig_ipv4_get_ifaddr(
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struct netconfig *netconfig,
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uint8_t proto)
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static struct l_rtnl_address *netconfig_get_static4_address(
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struct netconfig *netconfig)
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{
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const struct l_dhcp_lease *lease;
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struct netconfig_ifaddr *ifaddr;
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struct in_addr in_addr;
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char *netmask;
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struct l_rtnl_address *ifaddr = NULL;
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char *ip;
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char *netmask;
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struct in_addr in_addr;
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char *broadcast;
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uint32_t prefix_len;
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switch (proto) {
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case RTPROT_STATIC:
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ip = l_settings_get_string(netconfig->active_settings, "IPv4",
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ip = l_settings_get_string(netconfig->active_settings, "IPv4",
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"Address");
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if (!ip) {
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ip = l_settings_get_string(netconfig->active_settings,
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"IPv4", "ip");
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if (!ip)
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return NULL;
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}
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if (!ip)
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return NULL;
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ifaddr = l_new(struct netconfig_ifaddr, 1);
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ifaddr->ip = ip;
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netmask = l_settings_get_string(netconfig->active_settings,
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"IPv4", "Netmask");
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netmask = l_settings_get_string(netconfig->active_settings,
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"IPv4", "Netmask");
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if (!netmask)
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netmask = l_settings_get_string(
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netconfig->active_settings,
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"IPv4", "netmask");
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if (netmask && inet_pton(AF_INET, netmask, &in_addr) > 0)
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prefix_len = __builtin_popcountl(in_addr.s_addr);
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else
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prefix_len = 24;
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if (netmask && inet_pton(AF_INET, netmask, &in_addr) > 0)
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ifaddr->prefix_len = __builtin_popcountl(
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in_addr.s_addr);
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else
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ifaddr->prefix_len = 24;
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l_free(netmask);
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l_free(netmask);
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ifaddr = l_rtnl_address_new(ip, prefix_len);
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l_free(ip);
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ifaddr->broadcast =
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l_settings_get_string(netconfig->active_settings,
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"IPv4", "Broadcast");
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if (!ifaddr->broadcast)
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ifaddr->broadcast =
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l_settings_get_string(
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netconfig->active_settings,
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"IPv4", "broadcast");
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ifaddr->family = AF_INET;
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return ifaddr;
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case RTPROT_DHCP:
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lease = l_dhcp_client_get_lease(netconfig->dhcp_client);
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if (!lease)
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return NULL;
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ip = l_dhcp_lease_get_address(lease);
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if (!ip)
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return NULL;
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ifaddr = l_new(struct netconfig_ifaddr, 1);
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ifaddr->ip = ip;
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netmask = l_dhcp_lease_get_netmask(lease);
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if (netmask && inet_pton(AF_INET, netmask, &in_addr) > 0)
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ifaddr->prefix_len = __builtin_popcountl(
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in_addr.s_addr);
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else
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ifaddr->prefix_len = 24;
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l_free(netmask);
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ifaddr->broadcast = l_dhcp_lease_get_broadcast(lease);
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ifaddr->family = AF_INET;
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return ifaddr;
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if (!ifaddr) {
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l_error("Unable to parse IPv4.Address, ignoring...");
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return NULL;
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}
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return NULL;
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broadcast = l_settings_get_string(netconfig->active_settings,
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"IPv4", "Broadcast");
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if (broadcast) {
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bool r = l_rtnl_address_set_broadcast(ifaddr, broadcast);
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l_free(broadcast);
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if (!r) {
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l_error("Unable to parse IPv4.Broadcast, ignoring...");
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l_rtnl_address_free(ifaddr);
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return NULL;
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}
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}
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l_rtnl_address_set_noprefixroute(ifaddr, true);
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return ifaddr;
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}
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static char *netconfig_ipv4_get_gateway(struct netconfig *netconfig)
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@ -455,6 +422,41 @@ static struct l_rtnl_route *netconfig_get_static6_gateway(
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return ret;
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}
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static struct l_rtnl_address *netconfig_get_dhcp4_address(
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struct netconfig *netconfig)
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{
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const struct l_dhcp_lease *lease =
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l_dhcp_client_get_lease(netconfig->dhcp_client);
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L_AUTO_FREE_VAR(char *, ip) = NULL;
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L_AUTO_FREE_VAR(char *, netmask) = NULL;
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L_AUTO_FREE_VAR(char *, broadcast) = NULL;
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struct in_addr in_addr;
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uint32_t prefix_len;
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struct l_rtnl_address *ret;
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if (L_WARN_ON(!lease))
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return NULL;
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ip = l_dhcp_lease_get_address(lease);
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netmask = l_dhcp_lease_get_netmask(lease);
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broadcast = l_dhcp_lease_get_broadcast(lease);
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if (netmask && inet_pton(AF_INET, netmask, &in_addr) > 0)
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prefix_len = __builtin_popcountl(in_addr.s_addr);
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else
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prefix_len = 24;
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ret = l_rtnl_address_new(ip, prefix_len);
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if (!ret)
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return ret;
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if (broadcast)
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l_rtnl_address_set_broadcast(ret, broadcast);
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l_rtnl_address_set_noprefixroute(ret, true);
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return ret;
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}
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static bool netconfig_ifaddr_match(const void *a, const void *b)
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{
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const struct netconfig_ifaddr *entry = a;
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@ -472,32 +474,6 @@ static bool netconfig_ifaddr_match(const void *a, const void *b)
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return true;
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}
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static struct netconfig_ifaddr *netconfig_ifaddr_find(
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const struct netconfig *netconfig,
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uint8_t family, uint8_t prefix_len,
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const char *ip)
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{
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const struct l_queue_entry *entry;
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for (entry = l_queue_get_entries(netconfig->ifaddr_list); entry;
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entry = entry->next) {
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struct netconfig_ifaddr *ifaddr = entry->data;
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if (ifaddr->family != family)
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continue;
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if (ifaddr->prefix_len != prefix_len)
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continue;
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if (strcmp(ifaddr->ip, ip))
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continue;
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return ifaddr;
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}
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return NULL;
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}
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static void netconfig_ifaddr_added(struct netconfig *netconfig,
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const struct ifaddrmsg *ifa,
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uint32_t len)
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@ -705,26 +681,28 @@ static void netconfig_route_add_cmd_cb(int error, uint16_t type,
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netconfig->notify = NULL;
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}
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static bool netconfig_ipv4_routes_install(struct netconfig *netconfig,
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struct netconfig_ifaddr *ifaddr)
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static bool netconfig_ipv4_routes_install(struct netconfig *netconfig)
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{
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L_AUTO_FREE_VAR(char *, gateway) = NULL;
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struct in_addr in_addr;
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char *network;
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char ip[INET6_ADDRSTRLEN];
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unsigned int prefix_len =
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l_rtnl_address_get_prefix_length(netconfig->v4_address);
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if (inet_pton(AF_INET, ifaddr->ip, &in_addr) < 1)
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if (!l_rtnl_address_get_address(netconfig->v4_address, ip) ||
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inet_pton(AF_INET, ip, &in_addr) < 1)
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return false;
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in_addr.s_addr = in_addr.s_addr &
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htonl(0xFFFFFFFFLU << (32 - ifaddr->prefix_len));
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htonl(0xFFFFFFFFLU << (32 - prefix_len));
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network = inet_ntoa(in_addr);
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if (!network)
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return false;
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if (!l_rtnl_route4_add_connected(rtnl, netconfig->ifindex,
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ifaddr->prefix_len, network,
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ifaddr->ip,
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prefix_len, network, ip,
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netconfig->rtm_protocol,
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netconfig_route_add_cmd_cb,
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netconfig, NULL)) {
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@ -742,8 +720,7 @@ static bool netconfig_ipv4_routes_install(struct netconfig *netconfig,
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return false;
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}
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if (!l_rtnl_route4_add_gateway(rtnl, netconfig->ifindex, gateway,
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ifaddr->ip,
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if (!l_rtnl_route4_add_gateway(rtnl, netconfig->ifindex, gateway, ip,
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ROUTE_PRIORITY_OFFSET,
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netconfig->rtm_protocol,
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netconfig_route_add_cmd_cb,
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@ -762,7 +739,6 @@ static void netconfig_ipv4_ifaddr_add_cmd_cb(int error, uint16_t type,
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void *user_data)
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{
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struct netconfig *netconfig = user_data;
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struct netconfig_ifaddr *ifaddr;
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if (error && error != -EEXIST) {
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l_error("netconfig: Failed to add IP address. "
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@ -770,25 +746,13 @@ static void netconfig_ipv4_ifaddr_add_cmd_cb(int error, uint16_t type,
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return;
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}
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ifaddr = netconfig_ipv4_get_ifaddr(netconfig, netconfig->rtm_protocol);
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if (!ifaddr) {
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l_error("netconfig: Failed to obtain IP address from %s.",
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netconfig->rtm_protocol == RTPROT_STATIC ?
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"setting file" : "DHCPv4 lease");
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return;
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}
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if (!netconfig_ipv4_routes_install(netconfig, ifaddr)) {
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if (!netconfig_ipv4_routes_install(netconfig)) {
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l_error("netconfig: Failed to install IPv4 routes.");
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goto done;
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return;
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}
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netconfig_set_dns(netconfig);
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netconfig_set_domains(netconfig);
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done:
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netconfig_ifaddr_destroy(ifaddr);
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}
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static void netconfig_ipv6_ifaddr_add_cmd_cb(int error, uint16_t type,
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@ -816,42 +780,6 @@ static void netconfig_ipv6_ifaddr_add_cmd_cb(int error, uint16_t type,
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netconfig_set_dns(netconfig);
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}
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static void netconfig_install_address(struct netconfig *netconfig,
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struct netconfig_ifaddr *ifaddr)
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{
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if (netconfig_ifaddr_find(netconfig, ifaddr->family, ifaddr->prefix_len,
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ifaddr->ip))
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return;
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switch (ifaddr->family) {
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case AF_INET:
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if (l_rtnl_ifaddr4_add(rtnl, netconfig->ifindex,
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ifaddr->prefix_len, ifaddr->ip,
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ifaddr->broadcast,
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netconfig_ipv4_ifaddr_add_cmd_cb,
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netconfig, NULL))
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return;
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l_error("netconfig: Failed to set IP %s/%u.", ifaddr->ip,
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ifaddr->prefix_len);
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break;
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case AF_INET6:
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if (l_rtnl_ifaddr6_add(rtnl, netconfig->ifindex,
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ifaddr->prefix_len, ifaddr->ip,
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netconfig_ipv6_ifaddr_add_cmd_cb,
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netconfig, NULL))
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return;
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l_error("netconfig: Failed to set IPv6 address %s/%u.",
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ifaddr->ip, ifaddr->prefix_len);
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break;
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default:
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l_error("netconfig: Unsupported address family: %u",
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ifaddr->family);
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break;
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}
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}
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static void netconfig_ifaddr_del_cmd_cb(int error, uint16_t type,
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const void *data, uint32_t len,
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void *user_data)
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@ -872,48 +800,11 @@ static void netconfig_ifaddr_del_cmd_cb(int error, uint16_t type,
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"Error %d: %s", error, strerror(-error));
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}
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static void netconfig_uninstall_address(struct netconfig *netconfig,
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struct netconfig_ifaddr *ifaddr)
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{
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if (!netconfig_ifaddr_find(netconfig, ifaddr->family,
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ifaddr->prefix_len, ifaddr->ip))
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return;
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switch (ifaddr->family) {
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case AF_INET:
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if (l_rtnl_ifaddr4_delete(rtnl, netconfig->ifindex,
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ifaddr->prefix_len, ifaddr->ip,
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ifaddr->broadcast,
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netconfig_ifaddr_del_cmd_cb, netconfig,
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NULL))
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return;
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l_error("netconfig: Failed to delete IP %s/%u.",
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ifaddr->ip, ifaddr->prefix_len);
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break;
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case AF_INET6:
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if (l_rtnl_ifaddr6_delete(rtnl, netconfig->ifindex,
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ifaddr->prefix_len, ifaddr->ip,
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netconfig_ifaddr_del_cmd_cb, netconfig,
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NULL))
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return;
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l_error("netconfig: Failed to delete IPv6 address %s/%u.",
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ifaddr->ip, ifaddr->prefix_len);
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break;
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default:
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l_error("netconfig: Unsupported address family: %u",
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ifaddr->family);
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break;
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}
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}
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static void netconfig_ipv4_dhcp_event_handler(struct l_dhcp_client *client,
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enum l_dhcp_client_event event,
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void *userdata)
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{
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struct netconfig *netconfig = userdata;
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struct netconfig_ifaddr *ifaddr;
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l_debug("DHCPv4 event %d", event);
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@ -921,29 +812,25 @@ static void netconfig_ipv4_dhcp_event_handler(struct l_dhcp_client *client,
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case L_DHCP_CLIENT_EVENT_LEASE_RENEWED:
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case L_DHCP_CLIENT_EVENT_LEASE_OBTAINED:
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case L_DHCP_CLIENT_EVENT_IP_CHANGED:
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ifaddr = netconfig_ipv4_get_ifaddr(netconfig, RTPROT_DHCP);
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if (!ifaddr) {
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netconfig->v4_address = netconfig_get_dhcp4_address(netconfig);
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if (!netconfig->v4_address) {
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l_error("netconfig: Failed to obtain IP addresses from "
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"DHCPv4 lease.");
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return;
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}
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netconfig_install_address(netconfig, ifaddr);
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netconfig_ifaddr_destroy(ifaddr);
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L_WARN_ON(!l_rtnl_ifaddr_add(rtnl, netconfig->ifindex,
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netconfig->v4_address,
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netconfig_ipv4_ifaddr_add_cmd_cb,
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netconfig, NULL));
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break;
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case L_DHCP_CLIENT_EVENT_LEASE_EXPIRED:
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ifaddr = netconfig_ipv4_get_ifaddr(netconfig, RTPROT_DHCP);
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if (!ifaddr) {
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l_error("netconfig: Failed to obtain IP addresses from "
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"DHCPv4 lease.");
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return;
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}
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netconfig_uninstall_address(netconfig, ifaddr);
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netconfig_ifaddr_destroy(ifaddr);
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L_WARN_ON(!l_rtnl_ifaddr_delete(rtnl, netconfig->ifindex,
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netconfig->v4_address,
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netconfig_ifaddr_del_cmd_cb,
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netconfig, NULL));
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l_rtnl_address_free(netconfig->v4_address);
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netconfig->v4_address = NULL;
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/* Fall through. */
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case L_DHCP_CLIENT_EVENT_NO_LEASE:
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@ -989,14 +876,13 @@ static void netconfig_dhcp6_event_handler(struct l_dhcp6_client *client,
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static void netconfig_ipv4_select_and_install(struct netconfig *netconfig)
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{
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struct netconfig_ifaddr *ifaddr;
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ifaddr = netconfig_ipv4_get_ifaddr(netconfig, RTPROT_STATIC);
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if (ifaddr) {
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netconfig->v4_address = netconfig_get_static4_address(netconfig);
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if (netconfig->v4_address) {
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netconfig->rtm_protocol = RTPROT_STATIC;
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netconfig_install_address(netconfig, ifaddr);
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netconfig_ifaddr_destroy(ifaddr);
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L_WARN_ON(!l_rtnl_ifaddr_add(rtnl, netconfig->ifindex,
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netconfig->v4_address,
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netconfig_ipv4_ifaddr_add_cmd_cb,
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netconfig, NULL));
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return;
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}
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@ -1009,19 +895,6 @@ static void netconfig_ipv4_select_and_install(struct netconfig *netconfig)
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netconfig->ifindex);
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}
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static void netconfig_ipv4_select_and_uninstall(struct netconfig *netconfig)
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{
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struct netconfig_ifaddr *ifaddr;
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ifaddr = netconfig_ipv4_get_ifaddr(netconfig, netconfig->rtm_protocol);
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if (ifaddr) {
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netconfig_uninstall_address(netconfig, ifaddr);
|
||||
netconfig_ifaddr_destroy(ifaddr);
|
||||
}
|
||||
|
||||
l_dhcp_client_stop(netconfig->dhcp_client);
|
||||
}
|
||||
|
||||
static void netconfig_ipv6_select_and_install(struct netconfig *netconfig)
|
||||
{
|
||||
struct netdev *netdev = netdev_find(netconfig->ifindex);
|
||||
@ -1149,20 +1022,37 @@ bool netconfig_reset(struct netconfig *netconfig)
|
||||
{
|
||||
struct netdev *netdev = netdev_find(netconfig->ifindex);
|
||||
|
||||
netconfig_ipv4_select_and_uninstall(netconfig);
|
||||
netconfig->rtm_protocol = 0;
|
||||
if (netconfig->rtm_protocol || netconfig->rtm_v6_protocol)
|
||||
resolve_revert(netconfig->resolve);
|
||||
|
||||
l_dhcp6_client_stop(netconfig->dhcp6_client);
|
||||
netconfig->rtm_v6_protocol = 0;
|
||||
if (netconfig->rtm_protocol) {
|
||||
if (netconfig->v4_address) {
|
||||
L_WARN_ON(!l_rtnl_ifaddr_delete(rtnl,
|
||||
netconfig->ifindex,
|
||||
netconfig->v4_address,
|
||||
netconfig_ifaddr_del_cmd_cb,
|
||||
netconfig, NULL));
|
||||
l_rtnl_address_free(netconfig->v4_address);
|
||||
netconfig->v4_address = NULL;
|
||||
}
|
||||
|
||||
resolve_revert(netconfig->resolve);
|
||||
l_strfreev(netconfig->dns4_overrides);
|
||||
netconfig->dns4_overrides = NULL;
|
||||
|
||||
l_strfreev(netconfig->dns4_overrides);
|
||||
netconfig->dns4_overrides = NULL;
|
||||
l_strfreev(netconfig->dns6_overrides);
|
||||
netconfig->dns6_overrides = NULL;
|
||||
l_dhcp_client_stop(netconfig->dhcp_client);
|
||||
netconfig->rtm_protocol = 0;
|
||||
}
|
||||
|
||||
sysfs_write_ipv6_setting(netdev_get_name(netdev), "disable_ipv6", "1");
|
||||
if (netconfig->rtm_v6_protocol) {
|
||||
l_strfreev(netconfig->dns6_overrides);
|
||||
netconfig->dns6_overrides = NULL;
|
||||
|
||||
l_dhcp6_client_stop(netconfig->dhcp6_client);
|
||||
netconfig->rtm_v6_protocol = 0;
|
||||
|
||||
sysfs_write_ipv6_setting(netdev_get_name(netdev),
|
||||
"disable_ipv6", "1");
|
||||
}
|
||||
|
||||
return true;
|
||||
}
|
||||
@ -1243,12 +1133,7 @@ void netconfig_destroy(struct netconfig *netconfig)
|
||||
|
||||
l_queue_remove(netconfig_list, netconfig);
|
||||
|
||||
if (netconfig->rtm_protocol)
|
||||
netconfig_ipv4_select_and_uninstall(netconfig);
|
||||
|
||||
if (netconfig->rtm_protocol || netconfig->rtm_v6_protocol)
|
||||
resolve_revert(netconfig->resolve);
|
||||
|
||||
netconfig_reset(netconfig);
|
||||
resolve_free(netconfig->resolve);
|
||||
netconfig_free(netconfig);
|
||||
}
|
||||
|
||||
Loading…
Reference in New Issue
Block a user