#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;
- uint32_t address;
- uint32_t server_address;
- uint32_t subnet_mask;
- uint32_t router;
+ be32_t address;
+ be32_t server_address;
+ be32_t subnet_mask;
+ be32_t router;
};
typedef struct DHCPLease DHCPLease;
sd_event_source *receive_message;
uint8_t *req_opts;
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;
};
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;
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);
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;
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:
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;
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)
if (err < 0)
return err;
- client_append_ip_headers(request, len);
+ 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);
+ err = dhcp_network_send_raw_socket(client->fd, &client->link,
+ request, len);
+ }
return err;
}
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;
- secs = (usec - client->start_time) / USEC_PER_SEC;
+ 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;
- if (client->attempt < 64)
- client->attempt *= 2;
+ next_timeout = usec + time_left * USEC_PER_SEC;
- next_timeout = usec + (client->attempt - 1) * USEC_PER_SEC +
- (random_u() & 0x1fffff);
+ 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_u() & 0x1fffff);
err = sd_event_add_monotonic(client->event, next_timeout,
10 * USEC_PER_MSEC,
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);
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:
- case DHCP_STATE_RENEWING:
- case DHCP_STATE_REBINDING:
break;
}
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)
{
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_receive_offer(sd_dhcp_client *client, DHCPPacket *offer,
- size_t len)
+static int client_verify_headers(sd_dhcp_client *client, DHCPPacket *message,
+ size_t len)
{
size_t hdrlen;
- DHCPLease *lease;
if (len < (DHCP_IP_UDP_SIZE + DHCP_MESSAGE_SIZE))
return -EINVAL;
- hdrlen = offer->ip.ihl * 4;
- if (hdrlen < 20 || hdrlen > len || client_checksum(&offer->ip,
+ hdrlen = message->ip.ihl * 4;
+ if (hdrlen < 20 || hdrlen > len || client_checksum(&message->ip,
hdrlen))
return -EINVAL;
- offer->ip.check = offer->udp.len;
- offer->ip.ttl = 0;
+ message->ip.check = message->udp.len;
+ message->ip.ttl = 0;
- if (hdrlen + be16toh(offer->udp.len) > len ||
- client_checksum(&offer->ip.ttl, be16toh(offer->udp.len) + 12))
+ if (hdrlen + be16toh(message->udp.len) > len ||
+ client_checksum(&message->ip.ttl, be16toh(message->udp.len) + 12))
return -EINVAL;
- if (be16toh(offer->udp.source) != DHCP_PORT_SERVER ||
- be16toh(offer->udp.dest) != DHCP_PORT_CLIENT)
+ if (be16toh(message->udp.source) != DHCP_PORT_SERVER ||
+ be16toh(message->udp.dest) != DHCP_PORT_CLIENT)
return -EINVAL;
- if (offer->dhcp.op != BOOTREPLY)
+ if (message->dhcp.op != BOOTREPLY)
return -EINVAL;
- if (be32toh(offer->dhcp.xid) != client->xid)
+ if (be32toh(message->dhcp.xid) != client->xid)
return -EINVAL;
- if (memcmp(&offer->dhcp.chaddr[0], &client->mac_addr.ether_addr_octet,
+ 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;
return -ENOMSG;
}
-static int client_receive_raw_message(sd_event_source *s, int fd,
- uint32_t revents, void *userdata)
+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_u() & 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, err = 0;
+ int len, r = 0, notify_event = 0;
DHCPPacket *message;
usec_t time_now;
if (len < 0)
return 0;
- err = sd_event_get_now_monotonic(client->event, &time_now);
- if (err < 0)
+ r = sd_event_get_now_monotonic(client->event, &time_now);
+ if (r < 0)
goto error;
- message = (DHCPPacket *)&buf;
-
switch (client->state) {
case DHCP_STATE_SELECTING:
+ message = (DHCPPacket *)&buf;
+
if (client_receive_offer(client, message, len) >= 0) {
client->timeout_resend =
client->state = DHCP_STATE_REQUESTING;
client->attempt = 1;
- err = sd_event_add_monotonic(client->event, time_now, 0,
- client_timeout_resend,
- client,
- &client->timeout_resend);
- if (err < 0)
+ 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_REQUESTING:
case DHCP_STATE_BOUND:
- case DHCP_STATE_RENEWING:
- case DHCP_STATE_REBINDING:
break;
}
error:
- if (err < 0)
- return client_stop(client, err);
+ 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 err;
+ int r;
assert_return(client, -EINVAL);
- assert_return(client->index >= 0, -EINVAL);
+ assert_return(client->index > 0, -EINVAL);
assert_return(client->state == DHCP_STATE_INIT ||
client->state == DHCP_STATE_INIT_REBOOT, -EBUSY);
client->xid = random_u();
- client->fd = dhcp_network_bind_raw_socket(client->index,
- &client->link);
+ r = dhcp_network_bind_raw_socket(client->index, &client->link);
- if (client->fd < 0) {
- err = client->fd;
- goto error;
+ if (r < 0) {
+ client_stop(client, r);
+ return r;
}
- err = sd_event_add_io(client->event, client->fd, EPOLLIN,
- client_receive_raw_message, client,
- &client->receive_message);
- if (err < 0)
- goto error;
-
+ client->fd = r;
client->start_time = now(CLOCK_MONOTONIC);
- err = sd_event_add_monotonic(client->event, client->start_time, 0,
- client_timeout_resend, client,
- &client->timeout_resend);
- if (err < 0)
- goto error;
- return 0;
-
-error:
- client_stop(client, err);
-
- return err;
+ 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)
~ianmdlvl / elogind.git / blobdiff