sd-dhcp6-client.c revision c806ffb9592fa9a2b13a1f9f9be4c77cd5b211aa
/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
/***
This file is part of systemd.
Copyright (C) 2014 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 <errno.h>
#include <string.h>
#include <sys/ioctl.h>
#include "udev.h"
#include "udev-util.h"
#include "virt.h"
#include "siphash24.h"
#include "util.h"
#include "refcnt.h"
#include "network-internal.h"
#include "sd-dhcp6-client.h"
#include "dhcp6-protocol.h"
#include "dhcp6-internal.h"
#include "dhcp6-lease-internal.h"
#define SYSTEMD_PEN 43793
#define HASH_KEY SD_ID128_MAKE(80,11,8c,c2,fe,4a,03,ee,3e,d6,0c,6f,36,39,14,09)
struct sd_dhcp6_client {
RefCount n_ref;
enum DHCP6State state;
sd_event *event;
int event_priority;
int index;
struct ether_addr mac_addr;
DHCP6IA ia_na;
be32_t transaction_id;
struct sd_dhcp6_lease *lease;
int fd;
sd_event_source *receive_message;
usec_t retransmit_time;
uint8_t retransmit_count;
sd_event_source *timeout_resend;
sd_event_source *timeout_resend_expire;
sd_dhcp6_client_cb_t cb;
void *userdata;
struct duid_en {
uint16_t type; /* DHCP6_DUID_EN */
uint32_t pen;
uint8_t id[8];
} _packed_ duid;
};
const char * dhcp6_message_type_table[_DHCP6_MESSAGE_MAX] = {
[DHCP6_SOLICIT] = "SOLICIT",
[DHCP6_ADVERTISE] = "ADVERTISE",
[DHCP6_REQUEST] = "REQUEST",
[DHCP6_CONFIRM] = "CONFIRM",
[DHCP6_RENEW] = "RENEW",
[DHCP6_REBIND] = "REBIND",
[DHCP6_REPLY] = "REPLY",
[DHCP6_RELEASE] = "RELEASE",
[DHCP6_DECLINE] = "DECLINE",
[DHCP6_RECONFIGURE] = "RECONFIGURE",
[DHCP6_INFORMATION_REQUEST] = "INFORMATION-REQUEST",
[DHCP6_RELAY_FORW] = "RELAY-FORW",
[DHCP6_RELAY_REPL] = "RELAY-REPL",
};
DEFINE_STRING_TABLE_LOOKUP(dhcp6_message_type, int);
const char * dhcp6_message_status_table[_DHCP6_STATUS_MAX] = {
[DHCP6_STATUS_SUCCESS] = "Success",
[DHCP6_STATUS_UNSPEC_FAIL] = "Unspecified failure",
[DHCP6_STATUS_NO_ADDRS_AVAIL] = "No addresses available",
[DHCP6_STATUS_NO_BINDING] = "Binding unavailable",
[DHCP6_STATUS_NOT_ON_LINK] = "Not on link",
[DHCP6_STATUS_USE_MULTICAST] = "Use multicast",
};
DEFINE_STRING_TABLE_LOOKUP(dhcp6_message_status, int);
static int client_start(sd_dhcp6_client *client, enum DHCP6State state);
int sd_dhcp6_client_set_callback(sd_dhcp6_client *client,
sd_dhcp6_client_cb_t cb, void *userdata)
{
assert_return(client, -EINVAL);
client->cb = cb;
client->userdata = userdata;
return 0;
}
int sd_dhcp6_client_set_index(sd_dhcp6_client *client, int interface_index)
{
assert_return(client, -EINVAL);
assert_return(interface_index >= -1, -EINVAL);
client->index = interface_index;
return 0;
}
int sd_dhcp6_client_set_mac(sd_dhcp6_client *client,
const struct ether_addr *mac_addr)
{
assert_return(client, -EINVAL);
if (mac_addr)
memcpy(&client->mac_addr, mac_addr, sizeof(client->mac_addr));
else
memset(&client->mac_addr, 0x00, sizeof(client->mac_addr));
return 0;
}
int sd_dhcp6_client_get_lease(sd_dhcp6_client *client, sd_dhcp6_lease **ret) {
assert_return(client, -EINVAL);
assert_return(ret, -EINVAL);
if (!client->lease)
return -ENOMSG;
*ret = sd_dhcp6_lease_ref(client->lease);
return 0;
}
static sd_dhcp6_client *client_notify(sd_dhcp6_client *client, int event) {
if (client->cb) {
client = sd_dhcp6_client_ref(client);
client->cb(client, event, client->userdata);
client = sd_dhcp6_client_unref(client);
}
return client;
}
static int client_reset(sd_dhcp6_client *client) {
assert_return(client, -EINVAL);
client->receive_message =
sd_event_source_unref(client->receive_message);
client->fd = safe_close(client->fd);
client->transaction_id = 0;
client->ia_na.timeout_t1 =
sd_event_source_unref(client->ia_na.timeout_t1);
client->ia_na.timeout_t2 =
sd_event_source_unref(client->ia_na.timeout_t2);
client->retransmit_time = 0;
client->retransmit_count = 0;
client->timeout_resend = sd_event_source_unref(client->timeout_resend);
client->timeout_resend_expire =
sd_event_source_unref(client->timeout_resend_expire);
client->state = DHCP6_STATE_STOPPED;
return 0;
}
static sd_dhcp6_client *client_stop(sd_dhcp6_client *client, int error) {
assert_return(client, NULL);
client = client_notify(client, error);
if (client)
client_reset(client);
return client;
}
static int client_send_message(sd_dhcp6_client *client) {
_cleanup_free_ DHCP6Message *message = NULL;
struct in6_addr all_servers =
IN6ADDR_ALL_DHCP6_RELAY_AGENTS_AND_SERVERS_INIT;
size_t len, optlen = 512;
uint8_t *opt;
int r;
len = sizeof(DHCP6Message) + optlen;
message = malloc0(len);
if (!message)
return -ENOMEM;
opt = (uint8_t *)(message + 1);
message->transaction_id = client->transaction_id;
switch(client->state) {
case DHCP6_STATE_SOLICITATION:
message->type = DHCP6_SOLICIT;
r = dhcp6_option_append_ia(&opt, &optlen, &client->ia_na);
if (r < 0)
return r;
break;
case DHCP6_STATE_REQUEST:
message->type = DHCP6_REQUEST;
r = dhcp6_option_append(&opt, &optlen, DHCP6_OPTION_SERVERID,
client->lease->serverid_len,
client->lease->serverid);
if (r < 0)
return r;
r = dhcp6_option_append_ia(&opt, &optlen, &client->lease->ia);
if (r < 0)
return r;
break;
case DHCP6_STATE_STOPPED:
case DHCP6_STATE_RS:
case DHCP6_STATE_BOUND:
return -EINVAL;
}
r = dhcp6_option_append(&opt, &optlen, DHCP6_OPTION_CLIENTID,
sizeof(client->duid), &client->duid);
if (r < 0)
return r;
r = dhcp6_network_send_udp_socket(client->fd, &all_servers, message,
len - optlen);
if (r < 0)
return r;
log_dhcp6_client(client, "Sent %s",
dhcp6_message_type_to_string(message->type));
return 0;
}
static int client_timeout_t2(sd_event_source *s, uint64_t usec,
void *userdata) {
sd_dhcp6_client *client = userdata;
assert_return(s, -EINVAL);
assert_return(client, -EINVAL);
assert_return(client->lease, -EINVAL);
client->lease->ia.timeout_t2 =
sd_event_source_unref(client->lease->ia.timeout_t2);
log_dhcp6_client(client, "Timeout T2");
return 0;
}
static int client_timeout_t1(sd_event_source *s, uint64_t usec,
void *userdata) {
sd_dhcp6_client *client = userdata;
assert_return(s, -EINVAL);
assert_return(client, -EINVAL);
assert_return(client->lease, -EINVAL);
client->lease->ia.timeout_t1 =
sd_event_source_unref(client->lease->ia.timeout_t1);
log_dhcp6_client(client, "Timeout T1");
return 0;
}
static int client_timeout_resend_expire(sd_event_source *s, uint64_t usec,
void *userdata) {
sd_dhcp6_client *client = userdata;
assert(s);
assert(client);
assert(client->event);
client_stop(client, DHCP6_EVENT_RESEND_EXPIRE);
return 0;
}
static usec_t client_timeout_compute_random(usec_t val) {
return val - val / 10 +
(random_u32() % (2 * USEC_PER_SEC)) * val / 10 / USEC_PER_SEC;
}
static int client_timeout_resend(sd_event_source *s, uint64_t usec,
void *userdata) {
int r = 0;
sd_dhcp6_client *client = userdata;
usec_t time_now, init_retransmit_time, max_retransmit_time;
usec_t max_retransmit_duration;
uint8_t max_retransmit_count;
char time_string[FORMAT_TIMESPAN_MAX];
assert(s);
assert(client);
assert(client->event);
client->timeout_resend = sd_event_source_unref(client->timeout_resend);
switch (client->state) {
case DHCP6_STATE_SOLICITATION:
if (client->retransmit_count && client->lease) {
client_start(client, DHCP6_STATE_REQUEST);
return 0;
}
init_retransmit_time = DHCP6_SOL_TIMEOUT;
max_retransmit_time = DHCP6_SOL_MAX_RT;
max_retransmit_count = 0;
max_retransmit_duration = 0;
break;
case DHCP6_STATE_REQUEST:
init_retransmit_time = DHCP6_REQ_TIMEOUT;
max_retransmit_time = DHCP6_REQ_MAX_RT;
max_retransmit_count = DHCP6_REQ_MAX_RC;
max_retransmit_duration = 0;
break;
case DHCP6_STATE_STOPPED:
case DHCP6_STATE_RS:
case DHCP6_STATE_BOUND:
return 0;
}
if (max_retransmit_count &&
client->retransmit_count >= max_retransmit_count) {
client_stop(client, DHCP6_EVENT_RETRANS_MAX);
return 0;
}
r = client_send_message(client);
if (r >= 0)
client->retransmit_count++;
r = sd_event_now(client->event, CLOCK_MONOTONIC, &time_now);
if (r < 0)
goto error;
if (!client->retransmit_time) {
client->retransmit_time =
client_timeout_compute_random(init_retransmit_time);
if (client->state == DHCP6_STATE_SOLICITATION)
client->retransmit_time += init_retransmit_time / 10;
} else {
if (max_retransmit_time &&
client->retransmit_time > max_retransmit_time / 2)
client->retransmit_time = client_timeout_compute_random(max_retransmit_time);
else
client->retransmit_time += client_timeout_compute_random(client->retransmit_time);
}
log_dhcp6_client(client, "Next retransmission in %s",
format_timespan(time_string, FORMAT_TIMESPAN_MAX,
client->retransmit_time, 0));
r = sd_event_add_time(client->event, &client->timeout_resend,
CLOCK_MONOTONIC,
time_now + client->retransmit_time,
10 * USEC_PER_MSEC, 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;
if (max_retransmit_duration && !client->timeout_resend_expire) {
log_dhcp6_client(client, "Max retransmission duration %"PRIu64" secs",
max_retransmit_duration / USEC_PER_SEC);
r = sd_event_add_time(client->event,
&client->timeout_resend_expire,
CLOCK_MONOTONIC,
time_now + max_retransmit_duration,
USEC_PER_SEC,
client_timeout_resend_expire, client);
if (r < 0)
goto error;
r = sd_event_source_set_priority(client->timeout_resend_expire,
client->event_priority);
if (r < 0)
goto error;
}
error:
if (r < 0)
client_stop(client, r);
return 0;
}
static int client_ensure_iaid(sd_dhcp6_client *client) {
const char *name = NULL;
uint64_t id;
assert(client);
if (client->ia_na.id)
return 0;
if (detect_container(NULL) <= 0) {
/* not in a container, udev will be around */
_cleanup_udev_unref_ struct udev *udev;
_cleanup_udev_device_unref_ struct udev_device *device;
char ifindex_str[2 + DECIMAL_STR_MAX(int)];
udev = udev_new();
if (!udev)
return -ENOMEM;
sprintf(ifindex_str, "n%d", client->index);
device = udev_device_new_from_device_id(udev, ifindex_str);
if (!device)
return -errno;
if (udev_device_get_is_initialized(device) <= 0)
/* not yet ready */
return -EBUSY;
name = net_get_name(device);
}
if (name)
siphash24((uint8_t*)&id, name, strlen(name), HASH_KEY.bytes);
else
/* fall back to mac address if no predictable name available */
siphash24((uint8_t*)&id, &client->mac_addr, ETH_ALEN,
HASH_KEY.bytes);
/* fold into 32 bits */
client->ia_na.id = (id & 0xffffffff) ^ (id >> 32);
return 0;
}
static int client_parse_message(sd_dhcp6_client *client,
DHCP6Message *message, size_t len,
sd_dhcp6_lease *lease) {
int r;
uint8_t *optval, *option = (uint8_t *)(message + 1), *id = NULL;
uint16_t optcode, status;
size_t optlen, id_len;
bool clientid = false;
be32_t iaid_lease;
while ((r = dhcp6_option_parse(&option, &len, &optcode, &optlen,
&optval)) >= 0) {
switch (optcode) {
case DHCP6_OPTION_CLIENTID:
if (clientid) {
log_dhcp6_client(client, "%s contains multiple clientids",
dhcp6_message_type_to_string(message->type));
return -EINVAL;
}
if (optlen != sizeof(client->duid) ||
memcmp(&client->duid, optval, optlen) != 0) {
log_dhcp6_client(client, "%s DUID does not match",
dhcp6_message_type_to_string(message->type));
return -EINVAL;
}
clientid = true;
break;
case DHCP6_OPTION_SERVERID:
r = dhcp6_lease_get_serverid(lease, &id, &id_len);
if (r >= 0 && id) {
log_dhcp6_client(client, "%s contains multiple serverids",
dhcp6_message_type_to_string(message->type));
return -EINVAL;
}
r = dhcp6_lease_set_serverid(lease, optval, optlen);
if (r < 0)
return r;
break;
case DHCP6_OPTION_PREFERENCE:
if (optlen != 1)
return -EINVAL;
r = dhcp6_lease_set_preference(lease, *optval);
if (r < 0)
return r;
break;
case DHCP6_OPTION_STATUS_CODE:
if (optlen < 2)
return -EINVAL;
status = optval[0] << 8 | optval[1];
if (status) {
log_dhcp6_client(client, "%s Status %s",
dhcp6_message_type_to_string(message->type),
dhcp6_message_status_to_string(status));
return -EINVAL;
}
break;
case DHCP6_OPTION_IA_NA:
r = dhcp6_option_parse_ia(&optval, &optlen, optcode,
&lease->ia);
if (r < 0 && r != -ENOMSG)
return r;
r = dhcp6_lease_get_iaid(lease, &iaid_lease);
if (r < 0)
return r;
if (client->ia_na.id != iaid_lease) {
log_dhcp6_client(client, "%s has wrong IAID",
dhcp6_message_type_to_string(message->type));
return -EINVAL;
}
break;
}
}
if ((r < 0 && r != -ENOMSG) || !clientid) {
log_dhcp6_client(client, "%s has incomplete options",
dhcp6_message_type_to_string(message->type));
return -EINVAL;
}
r = dhcp6_lease_get_serverid(lease, &id, &id_len);
if (r < 0)
log_dhcp6_client(client, "%s has no server id",
dhcp6_message_type_to_string(message->type));
return r;
}
static int client_receive_reply(sd_dhcp6_client *client, DHCP6Message *reply,
size_t len)
{
int r;
_cleanup_dhcp6_lease_free_ sd_dhcp6_lease *lease = NULL;
if (reply->type != DHCP6_REPLY)
return -EINVAL;
r = dhcp6_lease_new(&lease);
if (r < 0)
return -ENOMEM;
r = client_parse_message(client, reply, len, lease);
if (r < 0)
return r;
dhcp6_lease_clear_timers(&client->lease->ia);
client->lease = sd_dhcp6_lease_unref(client->lease);
client->lease = lease;
lease = NULL;
return DHCP6_STATE_BOUND;
}
static int client_receive_advertise(sd_dhcp6_client *client,
DHCP6Message *advertise, size_t len) {
int r;
_cleanup_dhcp6_lease_free_ sd_dhcp6_lease *lease = NULL;
uint8_t pref_advertise = 0, pref_lease = 0;
if (advertise->type != DHCP6_ADVERTISE)
return -EINVAL;
r = dhcp6_lease_new(&lease);
if (r < 0)
return r;
r = client_parse_message(client, advertise, len, lease);
if (r < 0)
return r;
r = dhcp6_lease_get_preference(lease, &pref_advertise);
if (r < 0)
return r;
r = dhcp6_lease_get_preference(client->lease, &pref_lease);
if (!client->lease || r < 0 || pref_advertise > pref_lease) {
sd_dhcp6_lease_unref(client->lease);
client->lease = lease;
lease = NULL;
r = 0;
}
if (pref_advertise == 255 || client->retransmit_count > 1)
r = DHCP6_STATE_REQUEST;
return r;
}
static int client_receive_message(sd_event_source *s, int fd, uint32_t revents,
void *userdata) {
sd_dhcp6_client *client = userdata;
_cleanup_free_ DHCP6Message *message;
int r, buflen, len;
assert(s);
assert(client);
assert(client->event);
r = ioctl(fd, FIONREAD, &buflen);
if (r < 0 || buflen <= 0)
buflen = DHCP6_MIN_OPTIONS_SIZE;
message = malloc0(buflen);
if (!message)
return -ENOMEM;
len = read(fd, message, buflen);
if ((size_t)len < sizeof(DHCP6Message)) {
log_dhcp6_client(client, "could not receive message from UDP socket: %s", strerror(errno));
return 0;
}
switch(message->type) {
case DHCP6_SOLICIT:
case DHCP6_REQUEST:
case DHCP6_CONFIRM:
case DHCP6_RENEW:
case DHCP6_REBIND:
case DHCP6_RELEASE:
case DHCP6_DECLINE:
case DHCP6_INFORMATION_REQUEST:
case DHCP6_RELAY_FORW:
case DHCP6_RELAY_REPL:
return 0;
case DHCP6_ADVERTISE:
case DHCP6_REPLY:
case DHCP6_RECONFIGURE:
break;
default:
log_dhcp6_client(client, "unknown message type %d",
message->type);
return 0;
}
if (client->transaction_id != (message->transaction_id &
htobe32(0x00ffffff)))
return 0;
switch (client->state) {
case DHCP6_STATE_SOLICITATION:
r = client_receive_advertise(client, message, len);
if (r == DHCP6_STATE_REQUEST)
client_start(client, r);
break;
case DHCP6_STATE_REQUEST:
r = client_receive_reply(client, message, len);
if (r < 0)
return 0;
if (r == DHCP6_STATE_BOUND) {
r = client_start(client, DHCP6_STATE_BOUND);
if (r < 0) {
client_stop(client, r);
return 0;
}
client = client_notify(client, DHCP6_EVENT_IP_ACQUIRE);
if (!client)
return 0;
}
break;
case DHCP6_STATE_BOUND:
break;
case DHCP6_STATE_STOPPED:
case DHCP6_STATE_RS:
return 0;
}
if (r >= 0) {
log_dhcp6_client(client, "Recv %s",
dhcp6_message_type_to_string(message->type));
}
return 0;
}
static int client_start(sd_dhcp6_client *client, enum DHCP6State state)
{
int r;
usec_t timeout, time_now;
char time_string[FORMAT_TIMESPAN_MAX];
assert_return(client, -EINVAL);
assert_return(client->event, -EINVAL);
assert_return(client->index > 0, -EINVAL);
assert_return(client->state != state, -EINVAL);
client->timeout_resend_expire =
sd_event_source_unref(client->timeout_resend_expire);
client->timeout_resend = sd_event_source_unref(client->timeout_resend);
client->retransmit_time = 0;
client->retransmit_count = 0;
switch (state) {
case DHCP6_STATE_STOPPED:
case DHCP6_STATE_RS:
case DHCP6_STATE_SOLICITATION:
r = client_ensure_iaid(client);
if (r < 0)
return r;
r = dhcp6_network_bind_udp_socket(client->index, NULL);
if (r < 0)
return r;
client->fd = r;
r = sd_event_add_io(client->event, &client->receive_message,
client->fd, EPOLLIN, client_receive_message,
client);
if (r < 0)
return r;
r = sd_event_source_set_priority(client->receive_message,
client->event_priority);
if (r < 0)
return r;
client->state = DHCP6_STATE_SOLICITATION;
break;
case DHCP6_STATE_REQUEST:
client->state = state;
break;
case DHCP6_STATE_BOUND:
r = sd_event_now(client->event, CLOCK_MONOTONIC, &time_now);
if (r < 0)
return r;
if (client->lease->ia.lifetime_t1 == 0xffffffff ||
client->lease->ia.lifetime_t2 == 0xffffffff) {
log_dhcp6_client(client, "infinite T1 0x%08x or T2 0x%08x",
be32toh(client->lease->ia.lifetime_t1),
be32toh(client->lease->ia.lifetime_t2));
return 0;
}
timeout = client_timeout_compute_random(be32toh(client->lease->ia.lifetime_t1) * USEC_PER_SEC);
log_dhcp6_client(client, "T1 expires in %s",
format_timespan(time_string,
FORMAT_TIMESPAN_MAX,
timeout, 0));
r = sd_event_add_time(client->event,
&client->lease->ia.timeout_t1,
CLOCK_MONOTONIC, time_now + timeout,
10 * USEC_PER_SEC, client_timeout_t1,
client);
if (r < 0)
return r;
r = sd_event_source_set_priority(client->lease->ia.timeout_t1,
client->event_priority);
if (r < 0)
return r;
timeout = client_timeout_compute_random(be32toh(client->lease->ia.lifetime_t2) * USEC_PER_SEC);
log_dhcp6_client(client, "T2 expires in %s",
format_timespan(time_string,
FORMAT_TIMESPAN_MAX,
timeout, 0));
r = sd_event_add_time(client->event,
&client->lease->ia.timeout_t2,
CLOCK_MONOTONIC, time_now + timeout,
10 * USEC_PER_SEC, client_timeout_t2,
client);
if (r < 0)
return r;
r = sd_event_source_set_priority(client->lease->ia.timeout_t2,
client->event_priority);
if (r < 0)
return r;
return 0;
}
client->transaction_id = random_u32() & htobe32(0x00ffffff);
r = sd_event_add_time(client->event, &client->timeout_resend,
CLOCK_MONOTONIC, 0, 0, client_timeout_resend,
client);
if (r < 0)
return r;
r = sd_event_source_set_priority(client->timeout_resend,
client->event_priority);
if (r < 0)
return r;
return 0;
}
int sd_dhcp6_client_stop(sd_dhcp6_client *client)
{
client_stop(client, DHCP6_EVENT_STOP);
return 0;
}
int sd_dhcp6_client_start(sd_dhcp6_client *client)
{
int r = 0;
assert_return(client, -EINVAL);
assert_return(client->event, -EINVAL);
assert_return(client->index > 0, -EINVAL);
r = client_reset(client);
if (r < 0)
return r;
return client_start(client, DHCP6_STATE_SOLICITATION);
}
int sd_dhcp6_client_attach_event(sd_dhcp6_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_dhcp6_client_detach_event(sd_dhcp6_client *client) {
assert_return(client, -EINVAL);
client->event = sd_event_unref(client->event);
return 0;
}
sd_event *sd_dhcp6_client_get_event(sd_dhcp6_client *client) {
if (!client)
return NULL;
return client->event;
}
sd_dhcp6_client *sd_dhcp6_client_ref(sd_dhcp6_client *client) {
if (client)
assert_se(REFCNT_INC(client->n_ref) >= 2);
return client;
}
sd_dhcp6_client *sd_dhcp6_client_unref(sd_dhcp6_client *client) {
if (client && REFCNT_DEC(client->n_ref) <= 0) {
client_reset(client);
sd_dhcp6_client_detach_event(client);
free(client);
return NULL;
}
return client;
}
DEFINE_TRIVIAL_CLEANUP_FUNC(sd_dhcp6_client*, sd_dhcp6_client_unref);
#define _cleanup_dhcp6_client_free_ _cleanup_(sd_dhcp6_client_unrefp)
int sd_dhcp6_client_new(sd_dhcp6_client **ret)
{
_cleanup_dhcp6_client_free_ sd_dhcp6_client *client = NULL;
sd_id128_t machine_id;
int r;
assert_return(ret, -EINVAL);
client = new0(sd_dhcp6_client, 1);
if (!client)
return -ENOMEM;
client->n_ref = REFCNT_INIT;
client->ia_na.type = DHCP6_OPTION_IA_NA;
client->index = -1;
client->fd = -1;
/* initialize DUID */
client->duid.type = htobe16(DHCP6_DUID_EN);
client->duid.pen = htobe32(SYSTEMD_PEN);
r = sd_id128_get_machine(&machine_id);
if (r < 0)
return r;
/* a bit of snake-oil perhaps, but no need to expose the machine-id
directly */
siphash24(client->duid.id, &machine_id, sizeof(machine_id),
HASH_KEY.bytes);
*ret = client;
client = NULL;
return 0;
}