diff options
Diffstat (limited to 'src/grp-network/libnetworkd-core/networkd-dhcp4.c')
-rw-r--r-- | src/grp-network/libnetworkd-core/networkd-dhcp4.c | 659 |
1 files changed, 659 insertions, 0 deletions
diff --git a/src/grp-network/libnetworkd-core/networkd-dhcp4.c b/src/grp-network/libnetworkd-core/networkd-dhcp4.c new file mode 100644 index 0000000000..fe565ad075 --- /dev/null +++ b/src/grp-network/libnetworkd-core/networkd-dhcp4.c @@ -0,0 +1,659 @@ +/*** + This file is part of systemd. + + Copyright 2013-2014 Tom Gundersen <teg@jklm.no> + + 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 <http://www.gnu.org/licenses/>. +***/ + +#include <netinet/ether.h> + +#include <linux/if.h> + +#include "basic/alloc-util.h" +#include "basic/hostname-util.h" +#include "systemd-network/dhcp-lease-internal.h" +#include "systemd-network/network-internal.h" + +#include "networkd.h" + +static int dhcp4_route_handler(sd_netlink *rtnl, sd_netlink_message *m, + void *userdata) { + _cleanup_link_unref_ Link *link = userdata; + int r; + + assert(link); + assert(link->dhcp4_messages > 0); + + link->dhcp4_messages--; + + r = sd_netlink_message_get_errno(m); + if (r < 0 && r != -EEXIST) { + log_link_error_errno(link, r, "Could not set DHCPv4 route: %m"); + link_enter_failed(link); + } + + if (link->dhcp4_messages == 0) { + link->dhcp4_configured = true; + link_check_ready(link); + } + + return 1; +} + +static int link_set_dhcp_routes(Link *link) { + struct in_addr gateway; + _cleanup_free_ sd_dhcp_route **static_routes = NULL; + int r, n, i; + + assert(link); + assert(link->dhcp_lease); + assert(link->network); + + if (!link->network->dhcp_use_routes) + return 0; + + r = sd_dhcp_lease_get_router(link->dhcp_lease, &gateway); + if (r < 0 && r != -ENODATA) + return log_link_warning_errno(link, r, "DHCP error: could not get gateway: %m"); + + 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) + return log_link_warning_errno(link, r, "DHCP error: could not get address: %m"); + + r = route_new(&route); + if (r < 0) + return log_link_error_errno(link, r, "Could not allocate route: %m"); + + route->protocol = RTPROT_DHCP; + + r = route_new(&route_gw); + if (r < 0) + return log_link_error_errno(link, r, "Could not allocate route: %m"); + + /* 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.in = gateway; + route_gw->dst_prefixlen = 32; + route_gw->prefsrc.in = address; + route_gw->scope = RT_SCOPE_LINK; + route_gw->protocol = RTPROT_DHCP; + route_gw->priority = link->network->dhcp_route_metric; + + r = route_configure(route_gw, link, dhcp4_route_handler); + if (r < 0) + return log_link_warning_errno(link, r, "Could not set host route: %m"); + + link->dhcp4_messages++; + + route->family = AF_INET; + route->gw.in = gateway; + route->prefsrc.in = address; + route->priority = link->network->dhcp_route_metric; + + r = route_configure(route, link, dhcp4_route_handler); + if (r < 0) { + log_link_warning_errno(link, r, "Could not set routes: %m"); + link_enter_failed(link); + return r; + } + + link->dhcp4_messages++; + } + + n = sd_dhcp_lease_get_routes(link->dhcp_lease, &static_routes); + if (n == -ENODATA) + return 0; + if (n < 0) + return log_link_warning_errno(link, n, "DHCP error: could not get routes: %m"); + + for (i = 0; i < n; i++) { + _cleanup_route_free_ Route *route = NULL; + + r = route_new(&route); + if (r < 0) + return log_link_error_errno(link, r, "Could not allocate route: %m"); + + route->family = AF_INET; + route->protocol = RTPROT_DHCP; + assert_se(sd_dhcp_route_get_gateway(static_routes[i], &route->gw.in) >= 0); + assert_se(sd_dhcp_route_get_destination(static_routes[i], &route->dst.in) >= 0); + assert_se(sd_dhcp_route_get_destination_prefix_length(static_routes[i], &route->dst_prefixlen) >= 0); + route->priority = link->network->dhcp_route_metric; + + r = route_configure(route, link, dhcp4_route_handler); + if (r < 0) + return log_link_warning_errno(link, r, "Could not set host route: %m"); + + 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_link_warning(link, "DHCP lease lost"); + + if (link->network->dhcp_use_routes) { + _cleanup_free_ sd_dhcp_route **routes = NULL; + 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(&route); + if (r >= 0) { + route->family = AF_INET; + assert_se(sd_dhcp_route_get_gateway(routes[i], &route->gw.in) >= 0); + assert_se(sd_dhcp_route_get_destination(routes[i], &route->dst.in) >= 0); + assert_se(sd_dhcp_route_get_destination_prefix_length(routes[i], &route->dst_prefixlen) >= 0); + + route_remove(route, link, + link_route_remove_handler); + } + } + } + } + + r = address_new(&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(&route_gw); + if (r >= 0) { + route_gw->family = AF_INET; + route_gw->dst.in = gateway; + route_gw->dst_prefixlen = 32; + route_gw->scope = RT_SCOPE_LINK; + + route_remove(route_gw, link, + link_route_remove_handler); + } + + r = route_new(&route); + if (r >= 0) { + route->family = AF_INET; + route->gw.in = gateway; + + route_remove(route, link, + link_route_remove_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_remove(address, link, link_address_remove_handler); + } + } + + if (link->network->dhcp_use_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_link_warning(link, + "DHCP error: could not reset MTU"); + link_enter_failed(link); + return r; + } + } + } + + if (link->network->dhcp_use_hostname) { + const char *hostname = NULL; + + if (link->network->dhcp_hostname) + hostname = link->network->dhcp_hostname; + else + (void) sd_dhcp_lease_get_hostname(link->dhcp_lease, &hostname); + + if (hostname) { + /* If a hostname was set due to the lease, then unset it now. */ + r = link_set_hostname(link, NULL); + if (r < 0) + log_link_warning_errno(link, r, "Failed to reset transient hostname: %m"); + } + } + + link->dhcp_lease = sd_dhcp_lease_unref(link->dhcp_lease); + link_dirty(link); + link->dhcp4_configured = false; + + return 0; +} + +static int dhcp4_address_handler(sd_netlink *rtnl, sd_netlink_message *m, + void *userdata) { + _cleanup_link_unref_ Link *link = userdata; + int r; + + assert(link); + + r = sd_netlink_message_get_errno(m); + if (r < 0 && r != -EEXIST) { + log_link_error_errno(link, r, "Could not set DHCPv4 address: %m"); + link_enter_failed(link); + } else if (r >= 0) + manager_rtnl_process_address(rtnl, m, link->manager); + + 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(&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; + + /* allow reusing an existing address and simply update its lifetime + * in case it already exists */ + r = address_configure(addr, link, dhcp4_address_handler, true); + 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) + return log_link_warning_errno(link, r, "DHCP error: no lease: %m"); + + sd_dhcp_lease_unref(link->dhcp_lease); + link->dhcp4_configured = false; + link->dhcp_lease = sd_dhcp_lease_ref(lease); + link_dirty(link); + + r = sd_dhcp_lease_get_address(lease, &address); + if (r < 0) + return log_link_warning_errno(link, r, "DHCP error: no address: %m"); + + r = sd_dhcp_lease_get_netmask(lease, &netmask); + if (r < 0) + return log_link_warning_errno(link, r, "DHCP error: no netmask: %m"); + + if (!link->network->dhcp_critical) { + r = sd_dhcp_lease_get_lifetime(link->dhcp_lease, &lifetime); + if (r < 0) + return log_link_warning_errno(link, r, "DHCP error: no lifetime: %m"); + } + + r = dhcp4_update_address(link, &address, &netmask, lifetime); + if (r < 0) { + log_link_warning_errno(link, r, "Could not update IP address: %m"); + 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) + return log_link_error_errno(link, r, "DHCP error: No lease: %m"); + + r = sd_dhcp_lease_get_address(lease, &address); + if (r < 0) + return log_link_error_errno(link, r, "DHCP error: No address: %m"); + + r = sd_dhcp_lease_get_netmask(lease, &netmask); + if (r < 0) + return log_link_error_errno(link, r, "DHCP error: No netmask: %m"); + + prefixlen = in_addr_netmask_to_prefixlen(&netmask); + + r = sd_dhcp_lease_get_router(lease, &gateway); + if (r < 0 && r != -ENODATA) + return log_link_error_errno(link, r, "DHCP error: Could not get gateway: %m"); + + if (r >= 0) + log_struct(LOG_INFO, + LOG_LINK_INTERFACE(link), + LOG_LINK_MESSAGE(link, "DHCPv4 address %u.%u.%u.%u/%u via %u.%u.%u.%u", + 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(LOG_INFO, + LOG_LINK_INTERFACE(link), + LOG_LINK_MESSAGE(link, "DHCPv4 address %u.%u.%u.%u/%u", + ADDRESS_FMT_VAL(address), + prefixlen), + "ADDRESS=%u.%u.%u.%u", ADDRESS_FMT_VAL(address), + "PREFIXLEN=%u", prefixlen, + NULL); + + link->dhcp_lease = sd_dhcp_lease_ref(lease); + link_dirty(link); + + if (link->network->dhcp_use_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_link_error_errno(link, r, "Failed to set MTU to %" PRIu16 ": %m", mtu); + } + } + + if (link->network->dhcp_use_hostname) { + const char *hostname = NULL; + + if (link->network->dhcp_hostname) + hostname = link->network->dhcp_hostname; + else + (void) sd_dhcp_lease_get_hostname(lease, &hostname); + + if (hostname) { + r = link_set_hostname(link, hostname); + if (r < 0) + log_link_error_errno(link, r, "Failed to set transient hostname to '%s': %m", hostname); + } + } + + if (link->network->dhcp_use_timezone) { + const char *tz = NULL; + + (void) sd_dhcp_lease_get_timezone(link->dhcp_lease, &tz); + + if (tz) { + r = link_set_timezone(link, tz); + if (r < 0) + log_link_error_errno(link, r, "Failed to set timezone to '%s': %m", tz); + } + } + + if (!link->network->dhcp_critical) { + r = sd_dhcp_lease_get_lifetime(link->dhcp_lease, &lifetime); + if (r < 0) { + log_link_warning_errno(link, r, "DHCP error: no lifetime: %m"); + return r; + } + } + + r = dhcp4_update_address(link, &address, &netmask, lifetime); + if (r < 0) { + log_link_warning_errno(link, r, "Could not update IP address: %m"); + 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 SD_DHCP_CLIENT_EVENT_EXPIRED: + case SD_DHCP_CLIENT_EVENT_STOP: + case SD_DHCP_CLIENT_EVENT_IP_CHANGE: + if (link->network->dhcp_critical) { + log_link_error(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 == SD_DHCP_CLIENT_EVENT_IP_CHANGE) { + r = dhcp_lease_acquired(client, link); + if (r < 0) { + link_enter_failed(link); + return; + } + } + + break; + case SD_DHCP_CLIENT_EVENT_RENEW: + r = dhcp_lease_renew(client, link); + if (r < 0) { + link_enter_failed(link); + return; + } + break; + case SD_DHCP_CLIENT_EVENT_IP_ACQUIRE: + r = dhcp_lease_acquired(client, link); + if (r < 0) { + link_enter_failed(link); + return; + } + break; + default: + if (event < 0) + log_link_warning_errno(link, event, "DHCP error: Client failed: %m"); + else + log_link_warning(link, "DHCP unknown event: %i", event); + break; + } + + return; +} + +int dhcp4_configure(Link *link) { + int r; + + assert(link); + assert(link->network); + assert(link->network->dhcp & ADDRESS_FAMILY_IPV4); + + if (!link->dhcp_client) { + 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, + (const uint8_t *) &link->mac, + sizeof (link->mac), ARPHRD_ETHER); + 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_use_mtu) { + r = sd_dhcp_client_set_request_option(link->dhcp_client, + SD_DHCP_OPTION_INTERFACE_MTU); + if (r < 0) + return r; + } + + if (link->network->dhcp_use_routes) { + r = sd_dhcp_client_set_request_option(link->dhcp_client, + SD_DHCP_OPTION_STATIC_ROUTE); + if (r < 0) + return r; + r = sd_dhcp_client_set_request_option(link->dhcp_client, + SD_DHCP_OPTION_CLASSLESS_STATIC_ROUTE); + if (r < 0) + return r; + } + + /* Always acquire the timezone and NTP */ + r = sd_dhcp_client_set_request_option(link->dhcp_client, SD_DHCP_OPTION_NTP_SERVER); + if (r < 0) + return r; + + r = sd_dhcp_client_set_request_option(link->dhcp_client, SD_DHCP_OPTION_NEW_TZDB_TIMEZONE); + if (r < 0) + return r; + + if (link->network->dhcp_send_hostname) { + _cleanup_free_ char *hostname = NULL; + const char *hn = NULL; + + if (!link->network->dhcp_hostname) { + hostname = gethostname_malloc(); + if (!hostname) + return -ENOMEM; + + hn = hostname; + } else + hn = link->network->dhcp_hostname; + + if (!is_localhost(hn)) { + r = sd_dhcp_client_set_hostname(link->dhcp_client, hn); + 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; + } + + switch (link->network->dhcp_client_identifier) { + case DHCP_CLIENT_ID_DUID: { + /* If configured, apply user specified DUID and/or IAID */ + const DUID *duid = link_duid(link); + + r = sd_dhcp_client_set_iaid_duid(link->dhcp_client, + link->network->iaid, + duid->type, + duid->raw_data_len > 0 ? duid->raw_data : NULL, + duid->raw_data_len); + if (r < 0) + return r; + break; + } + case DHCP_CLIENT_ID_MAC: + r = sd_dhcp_client_set_client_id(link->dhcp_client, + ARPHRD_ETHER, + (const uint8_t *) &link->mac, + sizeof(link->mac)); + if (r < 0) + return r; + break; + default: + assert_not_reached("Unknown client identifier type."); + } + + return 0; +} |