#include <string.h>
#include <stdio.h>
#include <net/ethernet.h>
+#include <sys/param.h>
#include "util.h"
#include "list.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;
+};
+
+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;
- uint32_t last_addr;
+ 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_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;
if (client->req_opts[i] == option)
return -EEXIST;
- if (!GREEDY_REALLOC(client->req_opts, client->req_opts_size,
+ if (!GREEDY_REALLOC(client->req_opts, client->req_opts_allocated,
client->req_opts_size + 1))
return -ENOMEM;
- client->req_opts[client->req_opts_size - 1] = option;
+ client->req_opts[client->req_opts_size++] = option;
return 0;
}
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_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 int client_stop(sd_dhcp_client *client, int error)
{
assert_return(client, -EINVAL);
- assert_return(client->state != DHCP_STATE_INIT &&
- client->state != DHCP_STATE_INIT_REBOOT, -EALREADY);
+
+ 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_REQUESTING:
- case DHCP_STATE_BOUND:
case DHCP_STATE_RENEWING:
case DHCP_STATE_REBINDING:
break;
}
+ if (client->lease) {
+ free(client->lease);
+ client->lease = NULL;
+ }
+
return 0;
}
uint8_t **opt, size_t *optlen)
{
int err;
+ be16_t max_size;
*opt = (uint8_t *)(message + 1);
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;
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;
if (len & 0x01) {
odd = buf;
- sum += odd[len];
+ sum += odd[len - 1];
}
- return ~((sum & 0xffff) + (sum >> 16));
+ 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)
if (err < 0)
return err;
- discover->ip.version = IPVERSION;
- discover->ip.ihl = sizeof(discover->ip) >> 2;
- discover->ip.tot_len = htobe16(len);
+ client_append_ip_headers(discover, len);
- discover->ip.protocol = IPPROTO_UDP;
- discover->ip.saddr = INADDR_ANY;
- discover->ip.daddr = INADDR_BROADCAST;
+ err = dhcp_network_send_raw_socket(client->fd, &client->link,
+ discover, len);
- discover->udp.source = htobe16(DHCP_PORT_CLIENT);
- discover->udp.dest = htobe16(DHCP_PORT_SERVER);
- discover->udp.len = htobe16(len - sizeof(discover->ip));
+ return err;
+}
- discover->ip.check = discover->udp.len;
- discover->udp.check = client_checksum(&discover->ip.ttl,
- len - 8);
+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;
- discover->ip.ttl = IPDEFTTL;
- discover->ip.check = 0;
- discover->ip.check = client_checksum(&discover->ip,
- sizeof(discover->ip));
+ optlen = DHCP_CLIENT_MIN_OPTIONS_SIZE;
+ len = DHCP_MESSAGE_SIZE + optlen;
- err = dhcp_network_send_raw_packet(client->index, discover, len);
+ request = malloc0(len);
+ if (!request)
+ return -ENOMEM;
- return 0;
+ 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;
+ usec_t next_timeout = 0;
+ uint32_t time_left;
uint16_t secs;
int err = 0;
switch (client->state) {
- case DHCP_STATE_INIT:
- case DHCP_STATE_SELECTING:
+ case DHCP_STATE_RENEWING:
- if (!client->start_time)
- client->start_time = usec;
+ time_left = (client->lease->t2 - client->lease->t1)/2;
+ if (time_left < 60)
+ time_left = 60;
- secs = (usec - client->start_time) / USEC_PER_SEC;
+ next_timeout = usec + time_left * USEC_PER_SEC;
- next_timeout = usec + 2 * USEC_PER_SEC + (random() & 0x1fffff);
+ break;
- 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;
+ case DHCP_STATE_REBINDING:
- if (client_send_discover(client, secs) >= 0)
- client->state = DHCP_STATE_SELECTING;
+ 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;
}
-int sd_dhcp_client_start(sd_dhcp_client *client)
+static int client_initialize_events(sd_dhcp_client *client, usec_t usec)
{
- int err;
+ 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);
+ r = sd_event_add_io(client->event, client->fd, EPOLLIN,
+ client_receive_message, client,
+ &client->receive_message);
+ if (r < 0)
+ goto error;
- client->xid = random_u();
+ r = sd_event_add_monotonic(client->event, usec, 0,
+ client_timeout_resend, client,
+ &client->timeout_resend);
- err = sd_event_add_monotonic(client->event, now(CLOCK_MONOTONIC), 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_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:
- client_stop(client, err);
+ free(lease);
- return err;
+ 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, 0);
+ 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)
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);