1065 lines
32 KiB
C
1065 lines
32 KiB
C
/***
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This file is part of systemd.
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Copyright (C) 2013 Intel Corporation. All rights reserved.
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systemd is free software; you can redistribute it and/or modify it
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under the terms of the GNU Lesser General Public License as published by
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the Free Software Foundation; either version 2.1 of the License, or
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(at your option) any later version.
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systemd is distributed in the hope that it will be useful, but
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WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public License
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along with systemd; If not, see <http://www.gnu.org/licenses/>.
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***/
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#include <stdlib.h>
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#include <errno.h>
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#include <string.h>
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#include <stdio.h>
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#include <net/ethernet.h>
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#include <sys/param.h>
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#include <sys/ioctl.h>
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#include "util.h"
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#include "list.h"
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#include "dhcp-protocol.h"
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#include "dhcp-internal.h"
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#include "dhcp-lease-internal.h"
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#include "sd-dhcp-client.h"
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struct sd_dhcp_client {
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DHCPState state;
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sd_event *event;
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int event_priority;
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sd_event_source *timeout_resend;
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int index;
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int fd;
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union sockaddr_union link;
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sd_event_source *receive_message;
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uint8_t *req_opts;
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size_t req_opts_allocated;
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size_t req_opts_size;
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be32_t last_addr;
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struct ether_addr mac_addr;
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uint32_t xid;
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usec_t start_time;
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uint16_t secs;
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unsigned int attempt;
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usec_t request_sent;
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sd_event_source *timeout_t1;
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sd_event_source *timeout_t2;
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sd_event_source *timeout_expire;
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sd_dhcp_client_cb_t cb;
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void *userdata;
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sd_dhcp_lease *lease;
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};
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static const uint8_t default_req_opts[] = {
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DHCP_OPTION_SUBNET_MASK,
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DHCP_OPTION_ROUTER,
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DHCP_OPTION_HOST_NAME,
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DHCP_OPTION_DOMAIN_NAME,
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DHCP_OPTION_DOMAIN_NAME_SERVER,
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DHCP_OPTION_NTP_SERVER,
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};
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static int client_receive_message_raw(sd_event_source *s, int fd,
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uint32_t revents, void *userdata);
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static int client_receive_message_udp(sd_event_source *s, int fd,
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uint32_t revents, void *userdata);
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int sd_dhcp_client_set_callback(sd_dhcp_client *client, sd_dhcp_client_cb_t cb,
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void *userdata) {
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assert_return(client, -EINVAL);
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client->cb = cb;
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client->userdata = userdata;
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return 0;
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}
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int sd_dhcp_client_set_request_option(sd_dhcp_client *client, uint8_t option) {
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size_t i;
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assert_return(client, -EINVAL);
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assert_return (client->state == DHCP_STATE_INIT, -EBUSY);
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switch(option) {
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case DHCP_OPTION_PAD:
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case DHCP_OPTION_OVERLOAD:
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case DHCP_OPTION_MESSAGE_TYPE:
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case DHCP_OPTION_PARAMETER_REQUEST_LIST:
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case DHCP_OPTION_END:
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return -EINVAL;
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default:
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break;
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}
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for (i = 0; i < client->req_opts_size; i++)
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if (client->req_opts[i] == option)
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return -EEXIST;
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if (!GREEDY_REALLOC(client->req_opts, client->req_opts_allocated,
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client->req_opts_size + 1))
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return -ENOMEM;
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client->req_opts[client->req_opts_size++] = option;
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return 0;
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}
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int sd_dhcp_client_set_request_address(sd_dhcp_client *client,
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const struct in_addr *last_addr) {
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assert_return(client, -EINVAL);
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assert_return(client->state == DHCP_STATE_INIT, -EBUSY);
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if (last_addr)
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client->last_addr = last_addr->s_addr;
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else
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client->last_addr = INADDR_ANY;
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return 0;
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}
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int sd_dhcp_client_set_index(sd_dhcp_client *client, int interface_index) {
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assert_return(client, -EINVAL);
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assert_return(client->state == DHCP_STATE_INIT, -EBUSY);
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assert_return(interface_index >= -1, -EINVAL);
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client->index = interface_index;
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return 0;
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}
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int sd_dhcp_client_set_mac(sd_dhcp_client *client,
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const struct ether_addr *addr) {
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assert_return(client, -EINVAL);
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assert_return(client->state == DHCP_STATE_INIT, -EBUSY);
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log_dhcp_client(client, "set MAC address to "
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"%02hhx:%02hhx:%02hhx:%02hhx:%02hhx:%02hhx",
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addr->ether_addr_octet[0],
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addr->ether_addr_octet[1],
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addr->ether_addr_octet[2],
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addr->ether_addr_octet[3],
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addr->ether_addr_octet[4],
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addr->ether_addr_octet[5]);
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memcpy(&client->mac_addr, addr, ETH_ALEN);
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return 0;
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}
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int sd_dhcp_client_get_lease(sd_dhcp_client *client, sd_dhcp_lease **ret) {
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assert_return(client, -EINVAL);
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assert_return(ret, -EINVAL);
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if (client->state != DHCP_STATE_BOUND &&
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client->state != DHCP_STATE_RENEWING &&
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client->state != DHCP_STATE_REBINDING)
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return -EADDRNOTAVAIL;
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*ret = sd_dhcp_lease_ref(client->lease);
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return 0;
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}
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static int client_notify(sd_dhcp_client *client, int event) {
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if (client->cb)
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client->cb(client, event, client->userdata);
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return 0;
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}
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static int client_stop(sd_dhcp_client *client, int error) {
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assert_return(client, -EINVAL);
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client->receive_message =
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sd_event_source_unref(client->receive_message);
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client->fd = safe_close(client->fd);
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client->timeout_resend = sd_event_source_unref(client->timeout_resend);
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client->timeout_t1 = sd_event_source_unref(client->timeout_t1);
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client->timeout_t2 = sd_event_source_unref(client->timeout_t2);
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client->timeout_expire = sd_event_source_unref(client->timeout_expire);
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client->attempt = 1;
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client_notify(client, error);
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client->start_time = 0;
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client->secs = 0;
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client->state = DHCP_STATE_INIT;
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if (client->lease)
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client->lease = sd_dhcp_lease_unref(client->lease);
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log_dhcp_client(client, "STOPPED");
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return 0;
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}
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static int client_message_init(sd_dhcp_client *client, DHCPMessage *message,
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uint8_t type, uint16_t secs, uint8_t **opt,
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size_t *optlen) {
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int r;
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assert(secs);
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r = dhcp_message_init(message, BOOTREQUEST, client->xid, type, opt,
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optlen);
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if (r < 0)
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return r;
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/* Although 'secs' field is a SHOULD in RFC 2131, certain DHCP servers
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refuse to issue an DHCP lease if 'secs' is set to zero */
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message->secs = htobe16(secs);
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memcpy(&message->chaddr, &client->mac_addr, ETH_ALEN);
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if (client->state == DHCP_STATE_RENEWING ||
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client->state == DHCP_STATE_REBINDING)
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message->ciaddr = client->lease->address;
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/* Some DHCP servers will refuse to issue an DHCP lease if the Client
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Identifier option is not set */
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r = dhcp_option_append(opt, optlen, DHCP_OPTION_CLIENT_IDENTIFIER,
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ETH_ALEN, &client->mac_addr);
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if (r < 0)
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return r;
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if (type == DHCP_DISCOVER || type == DHCP_REQUEST) {
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be16_t max_size;
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r = dhcp_option_append(opt, optlen,
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DHCP_OPTION_PARAMETER_REQUEST_LIST,
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client->req_opts_size,
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client->req_opts);
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if (r < 0)
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return r;
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/* Some DHCP servers will send bigger DHCP packets than the
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defined default size unless the Maximum Messge Size option
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is explicitely set */
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max_size = htobe16(DHCP_IP_UDP_SIZE + DHCP_MESSAGE_SIZE +
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DHCP_MIN_OPTIONS_SIZE);
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r = dhcp_option_append(opt, optlen,
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DHCP_OPTION_MAXIMUM_MESSAGE_SIZE,
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2, &max_size);
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if (r < 0)
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return r;
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}
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return 0;
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}
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static int dhcp_client_send_raw(sd_dhcp_client *client, DHCPPacket *packet,
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size_t len) {
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dhcp_packet_append_ip_headers(packet, INADDR_ANY, DHCP_PORT_CLIENT,
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INADDR_BROADCAST, DHCP_PORT_SERVER, len);
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return dhcp_network_send_raw_socket(client->fd, &client->link,
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packet, len);
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}
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static int client_send_discover(sd_dhcp_client *client, uint16_t secs) {
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int err = 0;
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_cleanup_free_ DHCPPacket *discover;
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size_t optlen, len;
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uint8_t *opt;
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optlen = DHCP_MIN_OPTIONS_SIZE;
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len = sizeof(DHCPPacket) + optlen;
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discover = malloc0(len);
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if (!discover)
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return -ENOMEM;
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err = client_message_init(client, &discover->dhcp, DHCP_DISCOVER,
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secs, &opt, &optlen);
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if (err < 0)
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return err;
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if (client->last_addr != INADDR_ANY) {
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err = dhcp_option_append(&opt, &optlen,
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DHCP_OPTION_REQUESTED_IP_ADDRESS,
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4, &client->last_addr);
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if (err < 0)
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return err;
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}
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err = dhcp_option_append(&opt, &optlen, DHCP_OPTION_END, 0, NULL);
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if (err < 0)
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return err;
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err = dhcp_client_send_raw(client, discover, len);
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if (err < 0)
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return err;
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log_dhcp_client(client, "DISCOVER");
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return 0;
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}
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static int client_send_request(sd_dhcp_client *client, uint16_t secs) {
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_cleanup_free_ DHCPPacket *request;
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size_t optlen, len;
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int err;
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uint8_t *opt;
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optlen = DHCP_MIN_OPTIONS_SIZE;
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len = sizeof(DHCPPacket) + optlen;
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request = malloc0(len);
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if (!request)
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return -ENOMEM;
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err = client_message_init(client, &request->dhcp, DHCP_REQUEST, secs,
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&opt, &optlen);
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if (err < 0)
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return err;
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if (client->state == DHCP_STATE_REQUESTING) {
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err = dhcp_option_append(&opt, &optlen,
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DHCP_OPTION_REQUESTED_IP_ADDRESS,
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4, &client->lease->address);
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if (err < 0)
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return err;
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err = dhcp_option_append(&opt, &optlen,
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DHCP_OPTION_SERVER_IDENTIFIER,
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4, &client->lease->server_address);
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if (err < 0)
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return err;
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}
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err = dhcp_option_append(&opt, &optlen, DHCP_OPTION_END, 0, NULL);
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if (err < 0)
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return err;
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if (client->state == DHCP_STATE_RENEWING) {
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err = dhcp_network_send_udp_socket(client->fd,
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client->lease->server_address,
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DHCP_PORT_SERVER,
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&request->dhcp,
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len - DHCP_IP_UDP_SIZE);
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} else {
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err = dhcp_client_send_raw(client, request, len);
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}
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if (err < 0)
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return err;
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log_dhcp_client(client, "REQUEST");
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return 0;
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}
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static uint16_t client_update_secs(sd_dhcp_client *client, usec_t time_now)
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{
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client->secs = ((time_now - client->start_time) / USEC_PER_SEC) ? : 1;
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return client->secs;
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}
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static int client_timeout_resend(sd_event_source *s, uint64_t usec,
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void *userdata) {
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sd_dhcp_client *client = userdata;
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usec_t next_timeout = 0;
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uint64_t time_now;
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uint32_t time_left;
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int r;
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assert(s);
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assert(client);
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assert(client->event);
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r = sd_event_get_now_monotonic(client->event, &time_now);
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if (r < 0)
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goto error;
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switch (client->state) {
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case DHCP_STATE_RENEWING:
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time_left = (client->lease->t2 - client->lease->t1) / 2;
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if (time_left < 60)
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time_left = 60;
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next_timeout = time_now + time_left * USEC_PER_SEC;
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break;
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case DHCP_STATE_REBINDING:
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time_left = (client->lease->lifetime - client->lease->t2) / 2;
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if (time_left < 60)
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time_left = 60;
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next_timeout = time_now + time_left * USEC_PER_SEC;
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break;
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case DHCP_STATE_INIT:
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case DHCP_STATE_INIT_REBOOT:
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case DHCP_STATE_REBOOTING:
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case DHCP_STATE_SELECTING:
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case DHCP_STATE_REQUESTING:
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case DHCP_STATE_BOUND:
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if (client->attempt < 64)
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client->attempt *= 2;
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next_timeout = time_now + (client->attempt - 1) * USEC_PER_SEC;
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break;
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}
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next_timeout += (random_u32() & 0x1fffff);
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client->timeout_resend = sd_event_source_unref(client->timeout_resend);
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|
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r = sd_event_add_monotonic(client->event,
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&client->timeout_resend,
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next_timeout,
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10 * USEC_PER_MSEC,
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client_timeout_resend, client);
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if (r < 0)
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goto error;
|
|
|
|
r = sd_event_source_set_priority(client->timeout_resend,
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client->event_priority);
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if (r < 0)
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goto error;
|
|
|
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switch (client->state) {
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case DHCP_STATE_INIT:
|
|
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client_update_secs(client, time_now);
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|
|
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r = client_send_discover(client, client->secs);
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if (r >= 0) {
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client->state = DHCP_STATE_SELECTING;
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client->attempt = 1;
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} else {
|
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if (client->attempt >= 64)
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goto error;
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}
|
|
|
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break;
|
|
|
|
case DHCP_STATE_SELECTING:
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client_update_secs(client, time_now);
|
|
|
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r = client_send_discover(client, client->secs);
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if (r < 0 && client->attempt >= 64)
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goto error;
|
|
|
|
break;
|
|
|
|
case DHCP_STATE_REQUESTING:
|
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case DHCP_STATE_RENEWING:
|
|
case DHCP_STATE_REBINDING:
|
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r = client_send_request(client, client->secs);
|
|
if (r < 0 && client->attempt >= 64)
|
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goto error;
|
|
|
|
client->request_sent = time_now;
|
|
|
|
break;
|
|
|
|
case DHCP_STATE_INIT_REBOOT:
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case DHCP_STATE_REBOOTING:
|
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case DHCP_STATE_BOUND:
|
|
|
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break;
|
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}
|
|
|
|
return 0;
|
|
|
|
error:
|
|
client_stop(client, r);
|
|
|
|
/* Errors were dealt with when stopping the client, don't spill
|
|
errors into the event loop handler */
|
|
return 0;
|
|
}
|
|
|
|
static int client_initialize_events(sd_dhcp_client *client,
|
|
sd_event_io_handler_t io_callback) {
|
|
int r;
|
|
|
|
assert(client);
|
|
assert(client->event);
|
|
|
|
r = sd_event_add_io(client->event, &client->receive_message,
|
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client->fd, EPOLLIN, io_callback,
|
|
client);
|
|
if (r < 0)
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goto error;
|
|
|
|
r = sd_event_source_set_priority(client->receive_message,
|
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client->event_priority);
|
|
if (r < 0)
|
|
goto error;
|
|
|
|
client->timeout_resend = sd_event_source_unref(client->timeout_resend);
|
|
|
|
r = sd_event_add_monotonic(client->event,
|
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&client->timeout_resend, 0, 0,
|
|
client_timeout_resend, client);
|
|
if (r < 0)
|
|
goto error;
|
|
|
|
r = sd_event_source_set_priority(client->timeout_resend,
|
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client->event_priority);
|
|
|
|
error:
|
|
if (r < 0)
|
|
client_stop(client, r);
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
static int client_timeout_expire(sd_event_source *s, uint64_t usec,
|
|
void *userdata) {
|
|
sd_dhcp_client *client = userdata;
|
|
|
|
log_dhcp_client(client, "EXPIRED");
|
|
|
|
client_stop(client, DHCP_EVENT_EXPIRED);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int client_timeout_t2(sd_event_source *s, uint64_t usec, void *userdata) {
|
|
sd_dhcp_client *client = userdata;
|
|
int r;
|
|
|
|
client->receive_message = sd_event_source_unref(client->receive_message);
|
|
client->fd = safe_close(client->fd);
|
|
|
|
client->state = DHCP_STATE_REBINDING;
|
|
client->attempt = 1;
|
|
|
|
r = dhcp_network_bind_raw_socket(client->index, &client->link);
|
|
if (r < 0) {
|
|
client_stop(client, r);
|
|
return 0;
|
|
}
|
|
|
|
client->fd = r;
|
|
|
|
log_dhcp_client(client, "TIMEOUT T2");
|
|
|
|
return client_initialize_events(client, client_receive_message_raw);
|
|
}
|
|
|
|
static int client_timeout_t1(sd_event_source *s, uint64_t usec,
|
|
void *userdata) {
|
|
sd_dhcp_client *client = userdata;
|
|
int r;
|
|
|
|
client->state = DHCP_STATE_RENEWING;
|
|
client->attempt = 1;
|
|
|
|
r = dhcp_network_bind_udp_socket(client->index,
|
|
client->lease->address,
|
|
DHCP_PORT_CLIENT);
|
|
if (r < 0) {
|
|
client_stop(client, r);
|
|
return 0;
|
|
}
|
|
|
|
client->fd = r;
|
|
|
|
log_dhcp_client(client, "TIMEOUT T1");
|
|
|
|
return client_initialize_events(client, client_receive_message_udp);
|
|
}
|
|
|
|
static int client_handle_offer(sd_dhcp_client *client, DHCPMessage *offer,
|
|
size_t len) {
|
|
_cleanup_dhcp_lease_unref_ sd_dhcp_lease *lease = NULL;
|
|
int r;
|
|
|
|
r = dhcp_lease_new(&lease);
|
|
if (r < 0)
|
|
return r;
|
|
|
|
r = dhcp_option_parse(offer, len, dhcp_lease_parse_options, lease);
|
|
if (r != DHCP_OFFER)
|
|
return -ENOMSG;
|
|
|
|
lease->next_server = offer->siaddr;
|
|
|
|
lease->address = offer->yiaddr;
|
|
|
|
if (lease->address == INADDR_ANY ||
|
|
lease->server_address == INADDR_ANY ||
|
|
lease->subnet_mask == INADDR_ANY ||
|
|
lease->lifetime == 0)
|
|
return -ENOMSG;
|
|
|
|
client->lease = lease;
|
|
lease = NULL;
|
|
|
|
log_dhcp_client(client, "OFFER");
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int client_handle_ack(sd_dhcp_client *client, DHCPMessage *ack,
|
|
size_t len) {
|
|
_cleanup_dhcp_lease_unref_ sd_dhcp_lease *lease = NULL;
|
|
int r;
|
|
|
|
r = dhcp_lease_new(&lease);
|
|
if (r < 0)
|
|
return r;
|
|
|
|
r = dhcp_option_parse(ack, len, dhcp_lease_parse_options, lease);
|
|
if (r == DHCP_NAK) {
|
|
log_dhcp_client(client, "NAK");
|
|
return DHCP_EVENT_NO_LEASE;
|
|
}
|
|
|
|
if (r != DHCP_ACK)
|
|
return -ENOMSG;
|
|
|
|
lease->next_server = ack->siaddr;
|
|
|
|
lease->address = ack->yiaddr;
|
|
|
|
if (lease->address == INADDR_ANY ||
|
|
lease->server_address == INADDR_ANY ||
|
|
lease->subnet_mask == INADDR_ANY || lease->lifetime == 0)
|
|
return -ENOMSG;
|
|
|
|
r = DHCP_EVENT_IP_ACQUIRE;
|
|
if (client->lease) {
|
|
if (client->lease->address != lease->address ||
|
|
client->lease->subnet_mask != lease->subnet_mask ||
|
|
client->lease->router != lease->router) {
|
|
r = DHCP_EVENT_IP_CHANGE;
|
|
}
|
|
|
|
client->lease = sd_dhcp_lease_unref(client->lease);
|
|
}
|
|
|
|
client->lease = lease;
|
|
lease = NULL;
|
|
|
|
log_dhcp_client(client, "ACK");
|
|
|
|
return r;
|
|
}
|
|
|
|
static uint64_t client_compute_timeout(uint64_t request_sent,
|
|
uint32_t lifetime) {
|
|
return request_sent + (lifetime - 3) * USEC_PER_SEC +
|
|
+ (random_u32() & 0x1fffff);
|
|
}
|
|
|
|
static int client_set_lease_timeouts(sd_dhcp_client *client, uint64_t usec) {
|
|
uint64_t next_timeout;
|
|
int r;
|
|
|
|
assert(client);
|
|
assert(client->event);
|
|
|
|
if (client->lease->lifetime < 10)
|
|
return -EINVAL;
|
|
|
|
client->timeout_t1 = sd_event_source_unref(client->timeout_t1);
|
|
client->timeout_t2 = sd_event_source_unref(client->timeout_t2);
|
|
client->timeout_expire = sd_event_source_unref(client->timeout_expire);
|
|
|
|
if (!client->lease->t1)
|
|
client->lease->t1 = client->lease->lifetime / 2;
|
|
|
|
next_timeout = client_compute_timeout(client->request_sent,
|
|
client->lease->t1);
|
|
if (next_timeout < usec)
|
|
return -EINVAL;
|
|
|
|
r = sd_event_add_monotonic(client->event,
|
|
&client->timeout_t1,
|
|
next_timeout,
|
|
10 * USEC_PER_MSEC,
|
|
client_timeout_t1, client);
|
|
if (r < 0)
|
|
return r;
|
|
|
|
r = sd_event_source_set_priority(client->timeout_t1,
|
|
client->event_priority);
|
|
if (r < 0)
|
|
return r;
|
|
|
|
if (!client->lease->t2)
|
|
client->lease->t2 = client->lease->lifetime * 7 / 8;
|
|
|
|
if (client->lease->t2 < client->lease->t1)
|
|
return -EINVAL;
|
|
|
|
if (client->lease->lifetime < client->lease->t2)
|
|
return -EINVAL;
|
|
|
|
next_timeout = client_compute_timeout(client->request_sent,
|
|
client->lease->t2);
|
|
if (next_timeout < usec)
|
|
return -EINVAL;
|
|
|
|
r = sd_event_add_monotonic(client->event,
|
|
&client->timeout_t2,
|
|
next_timeout,
|
|
10 * USEC_PER_MSEC,
|
|
client_timeout_t2, client);
|
|
if (r < 0)
|
|
return r;
|
|
|
|
r = sd_event_source_set_priority(client->timeout_t2,
|
|
client->event_priority);
|
|
if (r < 0)
|
|
return r;
|
|
|
|
next_timeout = client_compute_timeout(client->request_sent,
|
|
client->lease->lifetime);
|
|
if (next_timeout < usec)
|
|
return -EINVAL;
|
|
|
|
r = sd_event_add_monotonic(client->event,
|
|
&client->timeout_expire, next_timeout,
|
|
10 * USEC_PER_MSEC,
|
|
client_timeout_expire, client);
|
|
if (r < 0)
|
|
return r;
|
|
|
|
r = sd_event_source_set_priority(client->timeout_expire,
|
|
client->event_priority);
|
|
if (r < 0)
|
|
return r;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int client_handle_message(sd_dhcp_client *client, DHCPMessage *message,
|
|
int len, usec_t time_now) {
|
|
int r = 0, notify_event = 0;
|
|
|
|
assert(client);
|
|
assert(client->event);
|
|
assert(message);
|
|
|
|
if (len < DHCP_MESSAGE_SIZE) {
|
|
log_dhcp_client(client, "message too small (%d bytes): "
|
|
"ignoring", len);
|
|
return 0;
|
|
}
|
|
|
|
if (message->op != BOOTREPLY) {
|
|
log_dhcp_client(client, "not a BOOTREPLY message: ignoring");
|
|
return 0;
|
|
}
|
|
|
|
if (be32toh(message->xid) != client->xid) {
|
|
log_dhcp_client(client, "received xid (%u) does not match "
|
|
"expected (%u): ignoring",
|
|
be32toh(message->xid), client->xid);
|
|
return 0;
|
|
}
|
|
|
|
if (memcmp(&message->chaddr[0], &client->mac_addr.ether_addr_octet,
|
|
ETHER_ADDR_LEN)) {
|
|
log_dhcp_client(client, "received chaddr does not match "
|
|
"expected: ignoring");
|
|
return 0;
|
|
}
|
|
|
|
switch (client->state) {
|
|
case DHCP_STATE_SELECTING:
|
|
|
|
r = client_handle_offer(client, message, len);
|
|
if (r >= 0) {
|
|
|
|
client->timeout_resend =
|
|
sd_event_source_unref(client->timeout_resend);
|
|
|
|
client->state = DHCP_STATE_REQUESTING;
|
|
client->attempt = 1;
|
|
|
|
r = sd_event_add_monotonic(client->event,
|
|
&client->timeout_resend, 0,
|
|
0, client_timeout_resend,
|
|
client);
|
|
if (r < 0)
|
|
goto error;
|
|
|
|
r = sd_event_source_set_priority(client->timeout_resend,
|
|
client->event_priority);
|
|
if (r < 0)
|
|
goto error;
|
|
}
|
|
|
|
break;
|
|
|
|
case DHCP_STATE_REQUESTING:
|
|
case DHCP_STATE_RENEWING:
|
|
case DHCP_STATE_REBINDING:
|
|
|
|
r = client_handle_ack(client, message, len);
|
|
|
|
if (r == DHCP_EVENT_NO_LEASE)
|
|
goto error;
|
|
|
|
if (r >= 0) {
|
|
client->timeout_resend =
|
|
sd_event_source_unref(client->timeout_resend);
|
|
|
|
if (client->state == DHCP_STATE_REQUESTING)
|
|
notify_event = DHCP_EVENT_IP_ACQUIRE;
|
|
else if (r != DHCP_EVENT_IP_ACQUIRE)
|
|
notify_event = r;
|
|
|
|
client->state = DHCP_STATE_BOUND;
|
|
client->attempt = 1;
|
|
|
|
client->last_addr = client->lease->address;
|
|
|
|
r = client_set_lease_timeouts(client, time_now);
|
|
if (r < 0)
|
|
goto error;
|
|
|
|
if (notify_event)
|
|
client_notify(client, notify_event);
|
|
|
|
client->receive_message =
|
|
sd_event_source_unref(client->receive_message);
|
|
client->fd = safe_close(client->fd);
|
|
}
|
|
|
|
r = 0;
|
|
|
|
break;
|
|
|
|
case DHCP_STATE_INIT:
|
|
case DHCP_STATE_INIT_REBOOT:
|
|
case DHCP_STATE_REBOOTING:
|
|
case DHCP_STATE_BOUND:
|
|
|
|
break;
|
|
}
|
|
|
|
error:
|
|
if (r < 0 || r == DHCP_EVENT_NO_LEASE)
|
|
return client_stop(client, r);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int client_receive_message_udp(sd_event_source *s, int fd,
|
|
uint32_t revents, void *userdata) {
|
|
sd_dhcp_client *client = userdata;
|
|
_cleanup_free_ DHCPMessage *message = NULL;
|
|
int buflen = 0, len, r;
|
|
usec_t time_now;
|
|
|
|
assert(s);
|
|
assert(client);
|
|
assert(client->event);
|
|
|
|
r = ioctl(fd, FIONREAD, &buflen);
|
|
if (r < 0 || buflen <= 0)
|
|
buflen = sizeof(DHCPMessage) + DHCP_MIN_OPTIONS_SIZE;
|
|
|
|
message = malloc0(buflen);
|
|
if (!message)
|
|
return -ENOMEM;
|
|
|
|
len = read(fd, message, buflen);
|
|
if (len < 0)
|
|
return 0;
|
|
|
|
r = sd_event_get_now_monotonic(client->event, &time_now);
|
|
if (r < 0)
|
|
return client_stop(client, r);
|
|
|
|
return client_handle_message(client, message, len,
|
|
time_now);
|
|
}
|
|
|
|
static int client_receive_message_raw(sd_event_source *s, int fd,
|
|
uint32_t revents, void *userdata) {
|
|
sd_dhcp_client *client = userdata;
|
|
_cleanup_free_ DHCPPacket *packet = NULL;
|
|
usec_t time_now;
|
|
uint8_t cmsgbuf[CMSG_LEN(sizeof(struct tpacket_auxdata))];
|
|
struct iovec iov = {};
|
|
struct msghdr msg = {
|
|
.msg_iov = &iov,
|
|
.msg_iovlen = 1,
|
|
.msg_control = cmsgbuf,
|
|
.msg_controllen = sizeof(cmsgbuf),
|
|
};
|
|
struct cmsghdr *cmsg;
|
|
bool checksum = true;
|
|
int buflen = 0, len, r;
|
|
|
|
assert(s);
|
|
assert(client);
|
|
assert(client->event);
|
|
|
|
r = ioctl(fd, FIONREAD, &buflen);
|
|
if (r < 0 || buflen <= 0)
|
|
buflen = sizeof(DHCPPacket) + DHCP_MIN_OPTIONS_SIZE;
|
|
|
|
packet = malloc0(buflen);
|
|
if (!packet)
|
|
return -ENOMEM;
|
|
|
|
iov.iov_base = packet;
|
|
iov.iov_len = buflen;
|
|
|
|
len = recvmsg(fd, &msg, 0);
|
|
if (len < 0) {
|
|
log_dhcp_client(client, "could not receive message from raw "
|
|
"socket: %s", strerror(errno));
|
|
return 0;
|
|
}
|
|
|
|
for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
|
|
if (cmsg->cmsg_level == SOL_PACKET && cmsg->cmsg_type == PACKET_AUXDATA) {
|
|
struct tpacket_auxdata *aux = (void *)CMSG_DATA(cmsg);
|
|
|
|
checksum = !(aux->tp_status & TP_STATUS_CSUMNOTREADY);
|
|
break;
|
|
}
|
|
}
|
|
|
|
r = dhcp_packet_verify_headers(packet, len, checksum);
|
|
if (r < 0)
|
|
return 0;
|
|
|
|
len -= DHCP_IP_UDP_SIZE;
|
|
|
|
r = sd_event_get_now_monotonic(client->event, &time_now);
|
|
if (r < 0)
|
|
return client_stop(client, r);
|
|
|
|
return client_handle_message(client, &packet->dhcp, len, time_now);
|
|
}
|
|
|
|
int sd_dhcp_client_start(sd_dhcp_client *client) {
|
|
int r;
|
|
|
|
assert_return(client, -EINVAL);
|
|
assert_return(client->event, -EINVAL);
|
|
assert_return(client->index > 0, -EINVAL);
|
|
assert_return(client->state == DHCP_STATE_INIT ||
|
|
client->state == DHCP_STATE_INIT_REBOOT, -EBUSY);
|
|
|
|
client->xid = random_u32();
|
|
|
|
r = dhcp_network_bind_raw_socket(client->index, &client->link);
|
|
|
|
if (r < 0) {
|
|
client_stop(client, r);
|
|
return r;
|
|
}
|
|
|
|
client->fd = r;
|
|
client->start_time = now(CLOCK_MONOTONIC);
|
|
client->secs = 0;
|
|
|
|
log_dhcp_client(client, "STARTED");
|
|
|
|
return client_initialize_events(client, client_receive_message_raw);
|
|
}
|
|
|
|
int sd_dhcp_client_stop(sd_dhcp_client *client) {
|
|
return client_stop(client, DHCP_EVENT_STOP);
|
|
}
|
|
|
|
int sd_dhcp_client_attach_event(sd_dhcp_client *client, sd_event *event,
|
|
int priority) {
|
|
int r;
|
|
|
|
assert_return(client, -EINVAL);
|
|
assert_return(!client->event, -EBUSY);
|
|
|
|
if (event)
|
|
client->event = sd_event_ref(event);
|
|
else {
|
|
r = sd_event_default(&client->event);
|
|
if (r < 0)
|
|
return 0;
|
|
}
|
|
|
|
client->event_priority = priority;
|
|
|
|
return 0;
|
|
}
|
|
|
|
int sd_dhcp_client_detach_event(sd_dhcp_client *client) {
|
|
assert_return(client, -EINVAL);
|
|
|
|
client->event = sd_event_unref(client->event);
|
|
|
|
return 0;
|
|
}
|
|
|
|
sd_event *sd_dhcp_client_get_event(sd_dhcp_client *client) {
|
|
if (!client)
|
|
return NULL;
|
|
|
|
return client->event;
|
|
}
|
|
|
|
void sd_dhcp_client_free(sd_dhcp_client *client) {
|
|
if (!client)
|
|
return;
|
|
|
|
sd_dhcp_client_stop(client);
|
|
sd_dhcp_client_detach_event(client);
|
|
|
|
free(client->req_opts);
|
|
free(client);
|
|
}
|
|
|
|
DEFINE_TRIVIAL_CLEANUP_FUNC(sd_dhcp_client*, sd_dhcp_client_free);
|
|
#define _cleanup_dhcp_client_free_ _cleanup_(sd_dhcp_client_freep)
|
|
|
|
int sd_dhcp_client_new(sd_dhcp_client **ret) {
|
|
_cleanup_dhcp_client_free_ sd_dhcp_client *client = NULL;
|
|
|
|
assert_return(ret, -EINVAL);
|
|
|
|
client = new0(sd_dhcp_client, 1);
|
|
if (!client)
|
|
return -ENOMEM;
|
|
|
|
client->state = DHCP_STATE_INIT;
|
|
client->index = -1;
|
|
client->fd = -1;
|
|
client->attempt = 1;
|
|
|
|
client->req_opts_size = ELEMENTSOF(default_req_opts);
|
|
|
|
client->req_opts = memdup(default_req_opts, client->req_opts_size);
|
|
if (!client->req_opts)
|
|
return -ENOMEM;
|
|
|
|
*ret = client;
|
|
client = NULL;
|
|
|
|
return 0;
|
|
}
|