diff options
Diffstat (limited to 'src/libsystemd-dhcp/dhcp-client.c')
| -rw-r--r-- | src/libsystemd-dhcp/dhcp-client.c | 1185 |
1 files changed, 0 insertions, 1185 deletions
diff --git a/src/libsystemd-dhcp/dhcp-client.c b/src/libsystemd-dhcp/dhcp-client.c deleted file mode 100644 index edfcb54a4c..0000000000 --- a/src/libsystemd-dhcp/dhcp-client.c +++ /dev/null @@ -1,1185 +0,0 @@ -/*** - This file is part of systemd. - - Copyright (C) 2013 Intel Corporation. All rights reserved. - - 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 <stdlib.h> -#include <errno.h> -#include <string.h> -#include <stdio.h> -#include <net/ethernet.h> -#include <sys/param.h> - -#include "util.h" -#include "list.h" - -#include "dhcp-protocol.h" -#include "dhcp-internal.h" -#include "sd-dhcp-client.h" - -#define DHCP_CLIENT_MIN_OPTIONS_SIZE 312 - -struct DHCPLease { - uint32_t t1; - uint32_t t2; - uint32_t lifetime; - be32_t address; - be32_t server_address; - be32_t subnet_mask; - be32_t router; - struct in_addr **dns; -}; - -typedef struct DHCPLease DHCPLease; - -struct sd_dhcp_client { - DHCPState state; - sd_event *event; - sd_event_source *timeout_resend; - int index; - int fd; - union sockaddr_union link; - sd_event_source *receive_message; - uint8_t *req_opts; - size_t req_opts_allocated; - size_t req_opts_size; - be32_t last_addr; - struct ether_addr mac_addr; - uint32_t xid; - usec_t start_time; - unsigned int attempt; - usec_t request_sent; - sd_event_source *timeout_t1; - sd_event_source *timeout_t2; - sd_event_source *timeout_expire; - sd_dhcp_client_cb_t cb; - void *userdata; - DHCPLease *lease; -}; - -static const uint8_t default_req_opts[] = { - DHCP_OPTION_SUBNET_MASK, - DHCP_OPTION_ROUTER, - DHCP_OPTION_HOST_NAME, - DHCP_OPTION_DOMAIN_NAME, - DHCP_OPTION_DOMAIN_NAME_SERVER, - DHCP_OPTION_NTP_SERVER, -}; - -static int client_receive_message(sd_event_source *s, int fd, - uint32_t revents, void *userdata); - -int sd_dhcp_client_set_callback(sd_dhcp_client *client, sd_dhcp_client_cb_t cb, - void *userdata) -{ - assert_return(client, -EINVAL); - - client->cb = cb; - client->userdata = userdata; - - return 0; -} - -int sd_dhcp_client_set_request_option(sd_dhcp_client *client, uint8_t option) -{ - size_t i; - - assert_return(client, -EINVAL); - assert_return (client->state == DHCP_STATE_INIT, -EBUSY); - - switch(option) { - case DHCP_OPTION_PAD: - case DHCP_OPTION_OVERLOAD: - case DHCP_OPTION_MESSAGE_TYPE: - case DHCP_OPTION_PARAMETER_REQUEST_LIST: - case DHCP_OPTION_END: - return -EINVAL; - - default: - break; - } - - for (i = 0; i < client->req_opts_size; i++) - if (client->req_opts[i] == option) - return -EEXIST; - - if (!GREEDY_REALLOC(client->req_opts, client->req_opts_allocated, - client->req_opts_size + 1)) - return -ENOMEM; - - client->req_opts[client->req_opts_size++] = option; - - return 0; -} - -int sd_dhcp_client_set_request_address(sd_dhcp_client *client, - const struct in_addr *last_addr) -{ - assert_return(client, -EINVAL); - assert_return(client->state == DHCP_STATE_INIT, -EBUSY); - - if (last_addr) - client->last_addr = last_addr->s_addr; - else - client->last_addr = INADDR_ANY; - - return 0; -} - -int sd_dhcp_client_set_index(sd_dhcp_client *client, int interface_index) -{ - assert_return(client, -EINVAL); - assert_return(client->state == DHCP_STATE_INIT, -EBUSY); - assert_return(interface_index >= -1, -EINVAL); - - client->index = interface_index; - - return 0; -} - -int sd_dhcp_client_set_mac(sd_dhcp_client *client, - const struct ether_addr *addr) -{ - assert_return(client, -EINVAL); - assert_return(client->state == DHCP_STATE_INIT, -EBUSY); - - memcpy(&client->mac_addr, addr, ETH_ALEN); - - return 0; -} - -int sd_dhcp_client_get_address(sd_dhcp_client *client, struct in_addr *addr) -{ - assert_return(client, -EINVAL); - assert_return(addr, -EINVAL); - - switch (client->state) { - case DHCP_STATE_INIT: - case DHCP_STATE_SELECTING: - case DHCP_STATE_INIT_REBOOT: - case DHCP_STATE_REBOOTING: - case DHCP_STATE_REQUESTING: - return -EADDRNOTAVAIL; - - case DHCP_STATE_BOUND: - case DHCP_STATE_RENEWING: - case DHCP_STATE_REBINDING: - addr->s_addr = client->lease->address; - - break; - } - - return 0; -} - -int sd_dhcp_client_get_netmask(sd_dhcp_client *client, struct in_addr *addr) -{ - assert_return(client, -EINVAL); - assert_return(addr, -EINVAL); - - switch (client->state) { - case DHCP_STATE_INIT: - case DHCP_STATE_SELECTING: - case DHCP_STATE_INIT_REBOOT: - case DHCP_STATE_REBOOTING: - case DHCP_STATE_REQUESTING: - return -EADDRNOTAVAIL; - - case DHCP_STATE_BOUND: - case DHCP_STATE_RENEWING: - case DHCP_STATE_REBINDING: - addr->s_addr = client->lease->subnet_mask; - - break; - } - - return 0; -} - -int sd_dhcp_client_get_dns(sd_dhcp_client *client, struct in_addr ***addr) -{ - assert_return(client, -EINVAL); - assert_return(addr, -EINVAL); - - switch (client->state) { - case DHCP_STATE_INIT: - case DHCP_STATE_SELECTING: - case DHCP_STATE_INIT_REBOOT: - case DHCP_STATE_REBOOTING: - case DHCP_STATE_REQUESTING: - return -EADDRNOTAVAIL; - - case DHCP_STATE_BOUND: - case DHCP_STATE_RENEWING: - case DHCP_STATE_REBINDING: - if (client->lease->dns) - *addr = client->lease->dns; - else - return -ENOENT; - - break; - } - - return 0; -} - -int sd_dhcp_client_prefixlen(const struct in_addr *addr) -{ - int len = 0; - uint32_t mask; - - assert_return(addr, -EADDRNOTAVAIL); - - mask = be32toh(addr->s_addr); - while (mask) { - len++; - mask = mask << 1; - } - - return len; -} - -int sd_dhcp_client_get_router(sd_dhcp_client *client, struct in_addr *addr) -{ - assert_return(client, -EINVAL); - assert_return(addr, -EINVAL); - - switch (client->state) { - case DHCP_STATE_INIT: - case DHCP_STATE_SELECTING: - case DHCP_STATE_INIT_REBOOT: - case DHCP_STATE_REBOOTING: - case DHCP_STATE_REQUESTING: - return -EADDRNOTAVAIL; - - case DHCP_STATE_BOUND: - case DHCP_STATE_RENEWING: - case DHCP_STATE_REBINDING: - addr->s_addr = client->lease->router; - - break; - } - - return 0; -} - -static int client_notify(sd_dhcp_client *client, int event) -{ - if (client->cb) - client->cb(client, event, client->userdata); - - return 0; -} - -static void in_addrs_free(struct in_addr **addrs) { - unsigned i; - - if (!addrs) - return; - - for (i = 0; addrs[i]; i++) - free(addrs[i]); - - free(addrs); -} - -static int client_stop(sd_dhcp_client *client, int error) -{ - assert_return(client, -EINVAL); - - client->receive_message = - sd_event_source_unref(client->receive_message); - - if (client->fd >= 0) - close(client->fd); - client->fd = -1; - - client->timeout_resend = sd_event_source_unref(client->timeout_resend); - - 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); - - client->attempt = 1; - - client_notify(client, error); - - switch (client->state) { - - case DHCP_STATE_INIT: - case DHCP_STATE_SELECTING: - case DHCP_STATE_REQUESTING: - case DHCP_STATE_BOUND: - - client->start_time = 0; - client->state = DHCP_STATE_INIT; - break; - - case DHCP_STATE_INIT_REBOOT: - case DHCP_STATE_REBOOTING: - case DHCP_STATE_RENEWING: - case DHCP_STATE_REBINDING: - - break; - } - - if (client->lease) { - in_addrs_free(client->lease->dns); - free(client->lease); - client->lease = NULL; - } - - return 0; -} - -static int client_packet_init(sd_dhcp_client *client, uint8_t type, - DHCPMessage *message, uint16_t secs, - uint8_t **opt, size_t *optlen) -{ - int err; - be16_t max_size; - - *opt = (uint8_t *)(message + 1); - - if (*optlen < 4) - return -ENOBUFS; - *optlen -= 4; - - message->op = BOOTREQUEST; - message->htype = 1; - message->hlen = ETHER_ADDR_LEN; - message->xid = htobe32(client->xid); - - /* Although 'secs' field is a SHOULD in RFC 2131, certain DHCP servers - refuse to issue an DHCP lease if 'secs' is set to zero */ - message->secs = htobe16(secs); - - if (client->state == DHCP_STATE_RENEWING || - client->state == DHCP_STATE_REBINDING) - message->ciaddr = client->lease->address; - - memcpy(&message->chaddr, &client->mac_addr, ETH_ALEN); - (*opt)[0] = 0x63; - (*opt)[1] = 0x82; - (*opt)[2] = 0x53; - (*opt)[3] = 0x63; - - *opt += 4; - - err = dhcp_option_append(opt, optlen, DHCP_OPTION_MESSAGE_TYPE, 1, - &type); - if (err < 0) - return err; - - /* Some DHCP servers will refuse to issue an DHCP lease if the Cliient - Identifier option is not set */ - err = dhcp_option_append(opt, optlen, DHCP_OPTION_CLIENT_IDENTIFIER, - ETH_ALEN, &client->mac_addr); - if (err < 0) - return err; - - if (type == DHCP_DISCOVER || type == DHCP_REQUEST) { - err = dhcp_option_append(opt, optlen, - DHCP_OPTION_PARAMETER_REQUEST_LIST, - client->req_opts_size, - client->req_opts); - if (err < 0) - return err; - - /* Some DHCP servers will send bigger DHCP packets than the - defined default size unless the Maximum Messge Size option - is explicitely set */ - max_size = htobe16(DHCP_IP_UDP_SIZE + DHCP_MESSAGE_SIZE + - DHCP_CLIENT_MIN_OPTIONS_SIZE); - err = dhcp_option_append(opt, optlen, - DHCP_OPTION_MAXIMUM_MESSAGE_SIZE, - 2, &max_size); - if (err < 0) - return err; - } - - return 0; -} - -static uint16_t client_checksum(void *buf, int len) -{ - uint32_t sum; - uint16_t *check; - int i; - uint8_t *odd; - - sum = 0; - check = buf; - - for (i = 0; i < len / 2 ; i++) - sum += check[i]; - - if (len & 0x01) { - odd = buf; - sum += odd[len - 1]; - } - - while (sum >> 16) - sum = (sum & 0xffff) + (sum >> 16); - - return ~sum; -} - -static void client_append_ip_headers(DHCPPacket *packet, uint16_t len) -{ - packet->ip.version = IPVERSION; - packet->ip.ihl = DHCP_IP_SIZE / 4; - packet->ip.tot_len = htobe16(len); - - packet->ip.protocol = IPPROTO_UDP; - packet->ip.saddr = INADDR_ANY; - packet->ip.daddr = INADDR_BROADCAST; - - packet->udp.source = htobe16(DHCP_PORT_CLIENT); - packet->udp.dest = htobe16(DHCP_PORT_SERVER); - packet->udp.len = htobe16(len - DHCP_IP_SIZE); - - packet->ip.check = packet->udp.len; - packet->udp.check = client_checksum(&packet->ip.ttl, len - 8); - - packet->ip.ttl = IPDEFTTL; - packet->ip.check = 0; - packet->ip.check = client_checksum(&packet->ip, DHCP_IP_SIZE); -} - -static int client_send_discover(sd_dhcp_client *client, uint16_t secs) -{ - int err = 0; - _cleanup_free_ DHCPPacket *discover; - size_t optlen, len; - uint8_t *opt; - - optlen = DHCP_CLIENT_MIN_OPTIONS_SIZE; - len = sizeof(DHCPPacket) + optlen; - - discover = malloc0(len); - - if (!discover) - return -ENOMEM; - - err = client_packet_init(client, DHCP_DISCOVER, &discover->dhcp, - secs, &opt, &optlen); - if (err < 0) - return err; - - if (client->last_addr != INADDR_ANY) { - err = dhcp_option_append(&opt, &optlen, - DHCP_OPTION_REQUESTED_IP_ADDRESS, - 4, &client->last_addr); - if (err < 0) - return err; - } - - err = dhcp_option_append(&opt, &optlen, DHCP_OPTION_END, 0, NULL); - if (err < 0) - return err; - - client_append_ip_headers(discover, len); - - err = dhcp_network_send_raw_socket(client->fd, &client->link, - discover, len); - - return err; -} - -static int client_send_request(sd_dhcp_client *client, uint16_t secs) -{ - _cleanup_free_ DHCPPacket *request; - size_t optlen, len; - int err; - uint8_t *opt; - - optlen = DHCP_CLIENT_MIN_OPTIONS_SIZE; - len = DHCP_MESSAGE_SIZE + optlen; - - request = malloc0(len); - if (!request) - return -ENOMEM; - - err = client_packet_init(client, DHCP_REQUEST, &request->dhcp, secs, - &opt, &optlen); - if (err < 0) - return err; - - if (client->state == DHCP_STATE_REQUESTING) { - err = dhcp_option_append(&opt, &optlen, - DHCP_OPTION_REQUESTED_IP_ADDRESS, - 4, &client->lease->address); - if (err < 0) - return err; - - err = dhcp_option_append(&opt, &optlen, - DHCP_OPTION_SERVER_IDENTIFIER, - 4, &client->lease->server_address); - if (err < 0) - return err; - } - - err = dhcp_option_append(&opt, &optlen, DHCP_OPTION_END, 0, NULL); - if (err < 0) - return err; - - if (client->state == DHCP_STATE_RENEWING) { - err = dhcp_network_send_udp_socket(client->fd, - client->lease->server_address, - &request->dhcp, - len - DHCP_IP_UDP_SIZE); - } else { - client_append_ip_headers(request, len); - - err = dhcp_network_send_raw_socket(client->fd, &client->link, - request, len); - } - - return err; -} - -static int client_timeout_resend(sd_event_source *s, uint64_t usec, - void *userdata) -{ - sd_dhcp_client *client = userdata; - usec_t next_timeout = 0; - uint32_t time_left; - uint16_t secs; - int err = 0; - - switch (client->state) { - case DHCP_STATE_RENEWING: - - time_left = (client->lease->t2 - client->lease->t1)/2; - if (time_left < 60) - time_left = 60; - - next_timeout = usec + time_left * USEC_PER_SEC; - - break; - - case DHCP_STATE_REBINDING: - - time_left = (client->lease->lifetime - client->lease->t2)/2; - if (time_left < 60) - time_left = 60; - - next_timeout = usec + time_left * USEC_PER_SEC; - break; - - case DHCP_STATE_INIT: - case DHCP_STATE_INIT_REBOOT: - case DHCP_STATE_REBOOTING: - case DHCP_STATE_SELECTING: - case DHCP_STATE_REQUESTING: - case DHCP_STATE_BOUND: - - if (client->attempt < 64) - client->attempt *= 2; - - next_timeout = usec + (client->attempt - 1) * USEC_PER_SEC; - - break; - } - - next_timeout += (random_u32() & 0x1fffff); - - err = sd_event_add_monotonic(client->event, next_timeout, - 10 * USEC_PER_MSEC, - client_timeout_resend, client, - &client->timeout_resend); - if (err < 0) - goto error; - - secs = (usec - client->start_time) / USEC_PER_SEC; - - switch (client->state) { - case DHCP_STATE_INIT: - err = client_send_discover(client, secs); - if (err >= 0) { - client->state = DHCP_STATE_SELECTING; - client->attempt = 1; - } else { - if (client->attempt >= 64) - goto error; - } - - break; - - case DHCP_STATE_SELECTING: - err = client_send_discover(client, secs); - if (err < 0 && client->attempt >= 64) - goto error; - - break; - - case DHCP_STATE_REQUESTING: - case DHCP_STATE_RENEWING: - case DHCP_STATE_REBINDING: - err = client_send_request(client, secs); - if (err < 0 && client->attempt >= 64) - goto error; - - client->request_sent = usec; - - break; - - case DHCP_STATE_INIT_REBOOT: - case DHCP_STATE_REBOOTING: - case DHCP_STATE_BOUND: - - break; - } - - return 0; - -error: - client_stop(client, err); - - /* 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, usec_t usec) -{ - int r; - - r = sd_event_add_io(client->event, client->fd, EPOLLIN, - client_receive_message, client, - &client->receive_message); - if (r < 0) - goto error; - - r = sd_event_add_monotonic(client->event, usec, 0, - client_timeout_resend, client, - &client->timeout_resend); - -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; - - 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; - - if (client->fd >= 0) { - client->receive_message = - sd_event_source_unref(client->receive_message); - close(client->fd); - client->fd = -1; - } - - 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; - - return client_initialize_events(client, usec); -} - -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); - if (r < 0) { - client_stop(client, r); - return 0; - } - - client->fd = r; - - return client_initialize_events(client, usec); -} - -static int client_parse_offer(uint8_t code, uint8_t len, const uint8_t *option, - void *user_data) -{ - DHCPLease *lease = user_data; - be32_t val; - - switch(code) { - - case DHCP_OPTION_IP_ADDRESS_LEASE_TIME: - if (len == 4) { - memcpy(&val, option, 4); - lease->lifetime = be32toh(val); - } - - break; - - case DHCP_OPTION_SERVER_IDENTIFIER: - if (len >= 4) - memcpy(&lease->server_address, option, 4); - - break; - - case DHCP_OPTION_SUBNET_MASK: - if (len >= 4) - memcpy(&lease->subnet_mask, option, 4); - - break; - - case DHCP_OPTION_ROUTER: - if (len >= 4) - memcpy(&lease->router, option, 4); - - break; - - case DHCP_OPTION_DOMAIN_NAME_SERVER: - if (len >= 4) { - unsigned i; - - in_addrs_free(lease->dns); - - lease->dns = new0(struct in_addr*, len / 4 + 1); - if (!lease->dns) - return -ENOMEM; - - for (i = 0; i < len / 4; i++) { - lease->dns[i] = new0(struct in_addr, 1); - memcpy(&lease->dns[i]->s_addr, option + 4 * i, 4); - } - - lease->dns[i + 1] = NULL; - } - - break; - - case DHCP_OPTION_RENEWAL_T1_TIME: - if (len == 4) { - memcpy(&val, option, 4); - lease->t1 = be32toh(val); - } - - break; - - case DHCP_OPTION_REBINDING_T2_TIME: - if (len == 4) { - memcpy(&val, option, 4); - lease->t2 = be32toh(val); - } - - break; - } - - return 0; -} - -static int client_verify_headers(sd_dhcp_client *client, DHCPPacket *message, - size_t len) -{ - size_t hdrlen; - - if (len < (DHCP_IP_UDP_SIZE + DHCP_MESSAGE_SIZE)) - return -EINVAL; - - hdrlen = message->ip.ihl * 4; - if (hdrlen < 20 || hdrlen > len || client_checksum(&message->ip, - hdrlen)) - return -EINVAL; - - message->ip.check = message->udp.len; - message->ip.ttl = 0; - - if (hdrlen + be16toh(message->udp.len) > len || - client_checksum(&message->ip.ttl, be16toh(message->udp.len) + 12)) - return -EINVAL; - - if (be16toh(message->udp.source) != DHCP_PORT_SERVER || - be16toh(message->udp.dest) != DHCP_PORT_CLIENT) - return -EINVAL; - - if (message->dhcp.op != BOOTREPLY) - return -EINVAL; - - if (be32toh(message->dhcp.xid) != client->xid) - return -EINVAL; - - if (memcmp(&message->dhcp.chaddr[0], &client->mac_addr.ether_addr_octet, - ETHER_ADDR_LEN)) - return -EINVAL; - - return 0; -} - -static int client_receive_offer(sd_dhcp_client *client, DHCPPacket *offer, - size_t len) -{ - int err; - DHCPLease *lease; - - err = client_verify_headers(client, offer, len); - if (err < 0) - return err; - - lease = new0(DHCPLease, 1); - if (!lease) - return -ENOMEM; - - len = len - DHCP_IP_UDP_SIZE; - if (dhcp_option_parse(&offer->dhcp, len, client_parse_offer, - lease) != DHCP_OFFER) - goto error; - - lease->address = offer->dhcp.yiaddr; - - if (lease->address == INADDR_ANY || - lease->server_address == INADDR_ANY || - lease->subnet_mask == INADDR_ANY || - lease->lifetime == 0) - goto error; - - client->lease = lease; - - return 0; - -error: - free(lease); - - return -ENOMSG; -} - -static int client_receive_ack(sd_dhcp_client *client, const uint8_t *buf, - size_t len) -{ - int r; - DHCPPacket *ack; - DHCPMessage *dhcp; - DHCPLease *lease; - - if (client->state == DHCP_STATE_RENEWING) { - dhcp = (DHCPMessage *)buf; - } else { - ack = (DHCPPacket *)buf; - - r = client_verify_headers(client, ack, len); - if (r < 0) - return r; - - dhcp = &ack->dhcp; - len -= DHCP_IP_UDP_SIZE; - } - - lease = new0(DHCPLease, 1); - if (!lease) - return -ENOMEM; - - r = dhcp_option_parse(dhcp, len, client_parse_offer, lease); - - if (r == DHCP_NAK) { - r = DHCP_EVENT_NO_LEASE; - goto error; - } - - if (r != DHCP_ACK) { - r = -ENOMSG; - goto error; - } - - lease->address = dhcp->yiaddr; - - if (lease->address == INADDR_ANY || - lease->server_address == INADDR_ANY || - lease->subnet_mask == INADDR_ANY || lease->lifetime == 0) { - r = -ENOMSG; - goto error; - } - - 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; - } - - free(client->lease); - } - - client->lease = lease; - - return r; - -error: - free(lease); - - 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) -{ - int err; - uint64_t next_timeout; - - 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; - - err = sd_event_add_monotonic(client->event, next_timeout, - 10 * USEC_PER_MSEC, - client_timeout_t1, client, - &client->timeout_t1); - if (err < 0) - return err; - - 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; - - err = sd_event_add_monotonic(client->event, next_timeout, - 10 * USEC_PER_MSEC, - client_timeout_t2, client, - &client->timeout_t2); - if (err < 0) - return err; - - next_timeout = client_compute_timeout(client->request_sent, - client->lease->lifetime); - if (next_timeout < usec) - return -EINVAL; - - err = sd_event_add_monotonic(client->event, next_timeout, - 10 * USEC_PER_MSEC, - client_timeout_expire, client, - &client->timeout_expire); - if (err < 0) - return err; - - return 0; -} - -static int client_receive_message(sd_event_source *s, int fd, - uint32_t revents, void *userdata) -{ - sd_dhcp_client *client = userdata; - uint8_t buf[sizeof(DHCPPacket) + DHCP_CLIENT_MIN_OPTIONS_SIZE]; - int buflen = sizeof(buf); - int len, r = 0, notify_event = 0; - DHCPPacket *message; - usec_t time_now; - - len = read(fd, &buf, buflen); - if (len < 0) - return 0; - - r = sd_event_get_now_monotonic(client->event, &time_now); - if (r < 0) - goto error; - - switch (client->state) { - case DHCP_STATE_SELECTING: - - message = (DHCPPacket *)&buf; - - if (client_receive_offer(client, message, len) >= 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, time_now, 0, - client_timeout_resend, - client, - &client->timeout_resend); - if (r < 0) - goto error; - } - - break; - - case DHCP_STATE_REQUESTING: - case DHCP_STATE_RENEWING: - case DHCP_STATE_REBINDING: - - r = client_receive_ack(client, buf, 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); - close(client->fd); - client->fd = -1; - } - - 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; -} - -int sd_dhcp_client_start(sd_dhcp_client *client) -{ - int r; - - assert_return(client, -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); - - return client_initialize_events(client, client->start_time); -} - -int sd_dhcp_client_stop(sd_dhcp_client *client) -{ - return client_stop(client, DHCP_EVENT_STOP); -} - -sd_dhcp_client *sd_dhcp_client_free(sd_dhcp_client *client) -{ - assert_return(client, NULL); - - sd_dhcp_client_stop(client); - - sd_event_unref(client->event); - free(client->req_opts); - free(client); - - return NULL; -} - -sd_dhcp_client *sd_dhcp_client_new(sd_event *event) -{ - sd_dhcp_client *client; - - assert_return(event, NULL); - - client = new0(sd_dhcp_client, 1); - if (!client) - return NULL; - - client->event = sd_event_ref(event); - 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) { - free(client); - return NULL; - } - - return client; -} |