From 3c9b886068d99e5d3cbabcac32a4decf37244c54 Mon Sep 17 00:00:00 2001 From: Tom Gundersen Date: Fri, 8 Aug 2014 12:12:17 +0200 Subject: networkd: link - split out dhcp4 handling --- src/network/networkd-dhcp4.c | 652 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 652 insertions(+) create mode 100644 src/network/networkd-dhcp4.c (limited to 'src/network/networkd-dhcp4.c') diff --git a/src/network/networkd-dhcp4.c b/src/network/networkd-dhcp4.c new file mode 100644 index 0000000000..499e813f20 --- /dev/null +++ b/src/network/networkd-dhcp4.c @@ -0,0 +1,652 @@ +/*-*- 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) { + _cleanup_route_free_ Route *route = NULL; + _cleanup_route_free_ Route *route_gw = NULL; + + 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->scope = RT_SCOPE_LINK; + route_gw->metrics = 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->metrics = 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 = 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; + 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); + } + } + + sd_dhcp_lease_get_address(link->dhcp_lease, &addr); + sd_dhcp_lease_get_netmask(link->dhcp_lease, &netmask); + 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(link->network->ipv4ll); + + 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; +} -- cgit v1.2.3-54-g00ecf