/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ /*** This file is part of systemd. Copyright 2013-2014 Tom Gundersen systemd is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. systemd is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with systemd; If not, see . ***/ #include #include #include "networkd-link.h" #include "network-internal.h" #include "dhcp-lease-internal.h" static int dhcp4_route_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) { _cleanup_link_unref_ Link *link = userdata; int r; assert(link); assert(link->dhcp4_messages); link->dhcp4_messages --; r = sd_rtnl_message_get_errno(m); if (r < 0 && r != -EEXIST) { log_error_link(link, "could not set DHCPv4 route: %s", strerror(-r)); link_enter_failed(link); } if (!link->dhcp4_messages) { link->dhcp4_configured = true; link_client_handler(link); } return 1; } static int link_set_dhcp_routes(Link *link) { struct in_addr gateway; struct sd_dhcp_route *static_routes; int r, n, i; assert(link); assert(link->dhcp_lease); r = sd_dhcp_lease_get_router(link->dhcp_lease, &gateway); if (r < 0 && r != -ENOENT) { log_warning_link(link, "DHCP error: could not get gateway: %s", strerror(-r)); return r; } if (r >= 0) { struct in_addr address; _cleanup_route_free_ Route *route = NULL; _cleanup_route_free_ Route *route_gw = NULL; r = sd_dhcp_lease_get_address(link->dhcp_lease, &address); if (r < 0) { log_warning_link(link, "DHCP error: could not get address: %s", strerror(-r)); return r; } r = route_new_dynamic(&route, RTPROT_DHCP); if (r < 0) { log_error_link(link, "Could not allocate route: %s", strerror(-r)); return r; } r = route_new_dynamic(&route_gw, RTPROT_DHCP); if (r < 0) { log_error_link(link, "Could not allocate route: %s", strerror(-r)); return r; } /* The dhcp netmask may mask out the gateway. Add an explicit * route for the gw host so that we can route no matter the * netmask or existing kernel route tables. */ route_gw->family = AF_INET; route_gw->dst_addr.in = gateway; route_gw->dst_prefixlen = 32; route_gw->prefsrc_addr.in = address; route_gw->scope = RT_SCOPE_LINK; route_gw->metrics = link->network->dhcp_route_metric; r = route_configure(route_gw, link, &dhcp4_route_handler); if (r < 0) { log_warning_link(link, "could not set host route: %s", strerror(-r)); return r; } link->dhcp4_messages ++; route->family = AF_INET; route->in_addr.in = gateway; route->prefsrc_addr.in = address; route->metrics = link->network->dhcp_route_metric; r = route_configure(route, link, &dhcp4_route_handler); if (r < 0) { log_warning_link(link, "could not set routes: %s", strerror(-r)); link_enter_failed(link); return r; } link->dhcp4_messages ++; } n = sd_dhcp_lease_get_routes(link->dhcp_lease, &static_routes); if (n == -ENOENT) return 0; if (n < 0) { log_warning_link(link, "DHCP error: could not get routes: %s", strerror(-n)); return n; } for (i = 0; i < n; i++) { _cleanup_route_free_ Route *route = NULL; r = route_new_dynamic(&route, RTPROT_DHCP); if (r < 0) { log_error_link(link, "Could not allocate route: %s", strerror(-r)); return r; } route->family = AF_INET; route->in_addr.in = static_routes[i].gw_addr; route->dst_addr.in = static_routes[i].dst_addr; route->dst_prefixlen = static_routes[i].dst_prefixlen; route->metrics = link->network->dhcp_route_metric; r = route_configure(route, link, &dhcp4_route_handler); if (r < 0) { log_warning_link(link, "could not set host route: %s", strerror(-r)); return r; } link->dhcp4_messages ++; } return 0; } static int dhcp_lease_lost(Link *link) { _cleanup_address_free_ Address *address = NULL; struct in_addr addr; struct in_addr netmask; struct in_addr gateway; unsigned prefixlen = 0; int r; assert(link); assert(link->dhcp_lease); log_warning_link(link, "DHCP lease lost"); if (link->network->dhcp_routes) { struct sd_dhcp_route *routes; int n, i; n = sd_dhcp_lease_get_routes(link->dhcp_lease, &routes); if (n >= 0) { for (i = 0; i < n; i++) { _cleanup_route_free_ Route *route = NULL; r = route_new_dynamic(&route, RTPROT_UNSPEC); if (r >= 0) { route->family = AF_INET; route->in_addr.in = routes[i].gw_addr; route->dst_addr.in = routes[i].dst_addr; route->dst_prefixlen = routes[i].dst_prefixlen; route_drop(route, link, &link_route_drop_handler); } } } } r = address_new_dynamic(&address); if (r >= 0) { r = sd_dhcp_lease_get_router(link->dhcp_lease, &gateway); if (r >= 0) { _cleanup_route_free_ Route *route_gw = NULL; _cleanup_route_free_ Route *route = NULL; r = route_new_dynamic(&route_gw, RTPROT_UNSPEC); if (r >= 0) { route_gw->family = AF_INET; route_gw->dst_addr.in = gateway; route_gw->dst_prefixlen = 32; route_gw->scope = RT_SCOPE_LINK; route_drop(route_gw, link, &link_route_drop_handler); } r = route_new_dynamic(&route, RTPROT_UNSPEC); if (r >= 0) { route->family = AF_INET; route->in_addr.in = gateway; route_drop(route, link, &link_route_drop_handler); } } r = sd_dhcp_lease_get_address(link->dhcp_lease, &addr); if (r >= 0) { r = sd_dhcp_lease_get_netmask(link->dhcp_lease, &netmask); if (r >= 0) prefixlen = in_addr_netmask_to_prefixlen(&netmask); address->family = AF_INET; address->in_addr.in = addr; address->prefixlen = prefixlen; address_drop(address, link, &link_address_drop_handler); } } if (link->network->dhcp_mtu) { uint16_t mtu; r = sd_dhcp_lease_get_mtu(link->dhcp_lease, &mtu); if (r >= 0 && link->original_mtu != mtu) { r = link_set_mtu(link, link->original_mtu); if (r < 0) { log_warning_link(link, "DHCP error: could not reset MTU"); link_enter_failed(link); return r; } } } if (link->network->dhcp_hostname) { const char *hostname = NULL; r = sd_dhcp_lease_get_hostname(link->dhcp_lease, &hostname); if (r >= 0 && hostname) { r = link_set_hostname(link, ""); if (r < 0) log_error_link(link, "Failed to reset transient hostname"); } } link->dhcp_lease = sd_dhcp_lease_unref(link->dhcp_lease); link->dhcp4_configured = false; return 0; } static int dhcp4_address_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) { _cleanup_link_unref_ Link *link = userdata; int r; assert(link); r = sd_rtnl_message_get_errno(m); if (r < 0 && r != -EEXIST) { log_error_link(link, "could not set DHCPv4 address: %s", strerror(-r)); link_enter_failed(link); } else if (r >= 0) { /* calling handler directly so take a ref */ link_ref(link); link_get_address_handler(rtnl, m, link); } link_set_dhcp_routes(link); return 1; } static int dhcp4_update_address(Link *link, struct in_addr *address, struct in_addr *netmask, uint32_t lifetime) { _cleanup_address_free_ Address *addr = NULL; unsigned prefixlen; int r; assert(address); assert(netmask); assert(lifetime); prefixlen = in_addr_netmask_to_prefixlen(netmask); r = address_new_dynamic(&addr); if (r < 0) return r; addr->family = AF_INET; addr->in_addr.in.s_addr = address->s_addr; addr->cinfo.ifa_prefered = lifetime; addr->cinfo.ifa_valid = lifetime; addr->prefixlen = prefixlen; addr->broadcast.s_addr = address->s_addr | ~netmask->s_addr; /* use update rather than configure so that we will update the * lifetime of an existing address if it has already been configured */ r = address_update(addr, link, &dhcp4_address_handler); if (r < 0) return r; return 0; } static int dhcp_lease_renew(sd_dhcp_client *client, Link *link) { sd_dhcp_lease *lease; struct in_addr address; struct in_addr netmask; uint32_t lifetime = CACHE_INFO_INFINITY_LIFE_TIME; int r; assert(link); assert(client); assert(link->network); r = sd_dhcp_client_get_lease(client, &lease); if (r < 0) { log_warning_link(link, "DHCP error: no lease %s", strerror(-r)); return r; } sd_dhcp_lease_unref(link->dhcp_lease); link->dhcp4_configured = false; link->dhcp_lease = lease; r = sd_dhcp_lease_get_address(lease, &address); if (r < 0) { log_warning_link(link, "DHCP error: no address: %s", strerror(-r)); return r; } r = sd_dhcp_lease_get_netmask(lease, &netmask); if (r < 0) { log_warning_link(link, "DHCP error: no netmask: %s", strerror(-r)); return r; } if (!link->network->dhcp_critical) { r = sd_dhcp_lease_get_lifetime(link->dhcp_lease, &lifetime); if (r < 0) { log_warning_link(link, "DHCP error: no lifetime: %s", strerror(-r)); return r; } } r = dhcp4_update_address(link, &address, &netmask, lifetime); if (r < 0) { log_warning_link(link, "could not update IP address: %s", strerror(-r)); link_enter_failed(link); return r; } return 0; } static int dhcp_lease_acquired(sd_dhcp_client *client, Link *link) { sd_dhcp_lease *lease; struct in_addr address; struct in_addr netmask; struct in_addr gateway; unsigned prefixlen; uint32_t lifetime = CACHE_INFO_INFINITY_LIFE_TIME; int r; assert(client); assert(link); r = sd_dhcp_client_get_lease(client, &lease); if (r < 0) { log_warning_link(link, "DHCP error: no lease: %s", strerror(-r)); return r; } r = sd_dhcp_lease_get_address(lease, &address); if (r < 0) { log_warning_link(link, "DHCP error: no address: %s", strerror(-r)); return r; } r = sd_dhcp_lease_get_netmask(lease, &netmask); if (r < 0) { log_warning_link(link, "DHCP error: no netmask: %s", strerror(-r)); return r; } prefixlen = in_addr_netmask_to_prefixlen(&netmask); r = sd_dhcp_lease_get_router(lease, &gateway); if (r < 0 && r != -ENOENT) { log_warning_link(link, "DHCP error: could not get gateway: %s", strerror(-r)); return r; } if (r >= 0) log_struct_link(LOG_INFO, link, "MESSAGE=%-*s: DHCPv4 address %u.%u.%u.%u/%u via %u.%u.%u.%u", IFNAMSIZ, link->ifname, ADDRESS_FMT_VAL(address), prefixlen, ADDRESS_FMT_VAL(gateway), "ADDRESS=%u.%u.%u.%u", ADDRESS_FMT_VAL(address), "PREFIXLEN=%u", prefixlen, "GATEWAY=%u.%u.%u.%u", ADDRESS_FMT_VAL(gateway), NULL); else log_struct_link(LOG_INFO, link, "MESSAGE=%-*s: DHCPv4 address %u.%u.%u.%u/%u", IFNAMSIZ, link->ifname, ADDRESS_FMT_VAL(address), prefixlen, "ADDRESS=%u.%u.%u.%u", ADDRESS_FMT_VAL(address), "PREFIXLEN=%u", prefixlen, NULL); link->dhcp_lease = lease; if (link->network->dhcp_mtu) { uint16_t mtu; r = sd_dhcp_lease_get_mtu(lease, &mtu); if (r >= 0) { r = link_set_mtu(link, mtu); if (r < 0) log_error_link(link, "Failed to set MTU " "to %" PRIu16, mtu); } } if (link->network->dhcp_hostname) { const char *hostname; r = sd_dhcp_lease_get_hostname(lease, &hostname); if (r >= 0) { r = link_set_hostname(link, hostname); if (r < 0) log_error_link(link, "Failed to set transient hostname to '%s'", hostname); } } if (!link->network->dhcp_critical) { r = sd_dhcp_lease_get_lifetime(link->dhcp_lease, &lifetime); if (r < 0) { log_warning_link(link, "DHCP error: no lifetime: %s", strerror(-r)); return r; } } r = dhcp4_update_address(link, &address, &netmask, lifetime); if (r < 0) { log_warning_link(link, "could not update IP address: %s", strerror(-r)); link_enter_failed(link); return r; } return 0; } static void dhcp4_handler(sd_dhcp_client *client, int event, void *userdata) { Link *link = userdata; int r = 0; assert(link); assert(link->network); assert(link->manager); if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER)) return; switch (event) { case DHCP_EVENT_EXPIRED: case DHCP_EVENT_STOP: case DHCP_EVENT_IP_CHANGE: if (link->network->dhcp_critical) { log_error_link(link, "DHCPv4 connection considered system critical, ignoring request to reconfigure it."); return; } if (link->dhcp_lease) { r = dhcp_lease_lost(link); if (r < 0) { link_enter_failed(link); return; } } if (event == DHCP_EVENT_IP_CHANGE) { r = dhcp_lease_acquired(client, link); if (r < 0) { link_enter_failed(link); return; } } break; case DHCP_EVENT_RENEW: r = dhcp_lease_renew(client, link); if (r < 0) { link_enter_failed(link); return; } break; case DHCP_EVENT_IP_ACQUIRE: r = dhcp_lease_acquired(client, link); if (r < 0) { link_enter_failed(link); return; } break; default: if (event < 0) log_warning_link(link, "DHCP error: client failed: %s", strerror(-event)); else log_warning_link(link, "DHCP unknown event: %d", event); break; } return; } int dhcp4_configure(Link *link) { int r; assert(link); assert(link->network); assert(IN_SET(link->network->dhcp, DHCP_SUPPORT_BOTH, DHCP_SUPPORT_V4)); r = sd_dhcp_client_new(&link->dhcp_client); if (r < 0) return r; r = sd_dhcp_client_attach_event(link->dhcp_client, NULL, 0); if (r < 0) return r; r = sd_dhcp_client_set_mac(link->dhcp_client, &link->mac); if (r < 0) return r; r = sd_dhcp_client_set_index(link->dhcp_client, link->ifindex); if (r < 0) return r; r = sd_dhcp_client_set_callback(link->dhcp_client, dhcp4_handler, link); if (r < 0) return r; r = sd_dhcp_client_set_request_broadcast(link->dhcp_client, link->network->dhcp_broadcast); if (r < 0) return r; if (link->mtu) { r = sd_dhcp_client_set_mtu(link->dhcp_client, link->mtu); if (r < 0) return r; } if (link->network->dhcp_mtu) { r = sd_dhcp_client_set_request_option(link->dhcp_client, DHCP_OPTION_INTERFACE_MTU); if (r < 0) return r; } if (link->network->dhcp_routes) { r = sd_dhcp_client_set_request_option(link->dhcp_client, DHCP_OPTION_STATIC_ROUTE); if (r < 0) return r; r = sd_dhcp_client_set_request_option(link->dhcp_client, DHCP_OPTION_CLASSLESS_STATIC_ROUTE); if (r < 0) return r; } if (link->network->dhcp_sendhost) { _cleanup_free_ char *hostname = NULL; hostname = gethostname_malloc(); if (!hostname) return -ENOMEM; if (!is_localhost(hostname)) { r = sd_dhcp_client_set_hostname(link->dhcp_client, hostname); if (r < 0) return r; } } if (link->network->dhcp_vendor_class_identifier) { r = sd_dhcp_client_set_vendor_class_identifier(link->dhcp_client, link->network->dhcp_vendor_class_identifier); if (r < 0) return r; } return 0; }