#include "dhcp-internal.h"
#include "sd-dhcp-client.h"
-#define DHCP_CLIENT_MIN_OPTIONS_SIZE 312
-
struct sd_dhcp_client {
DHCPState state;
sd_event *event;
DHCP_OPTION_NTP_SERVER,
};
-static int client_receive_message(sd_event_source *s, int fd,
- uint32_t revents, void *userdata);
+static int client_receive_message_raw(sd_event_source *s, int fd,
+ uint32_t revents, void *userdata);
+static int client_receive_message_udp(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) {
if (client->lease)
client->lease = sd_dhcp_lease_unref(client->lease);
+ log_dhcp_client(client, "STOPPED");
+
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;
+static int client_message_init(sd_dhcp_client *client, DHCPMessage *message,
+ uint8_t type, uint16_t secs, uint8_t **opt,
+ size_t *optlen) {
+ int r;
- message->op = BOOTREQUEST;
- message->htype = 1;
- message->hlen = ETHER_ADDR_LEN;
- message->xid = htobe32(client->xid);
+ r = dhcp_message_init(message, BOOTREQUEST, client->xid, type,
+ secs, opt, optlen);
+ if (r < 0)
+ return r;
- /* 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);
+ memcpy(&message->chaddr, &client->mac_addr, ETH_ALEN);
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
+ /* Some DHCP servers will refuse to issue an DHCP lease if the Client
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;
+ r = dhcp_option_append(opt, optlen, DHCP_OPTION_CLIENT_IDENTIFIER,
+ ETH_ALEN, &client->mac_addr);
+ if (r < 0)
+ return r;
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;
+ be16_t max_size;
+
+ r = dhcp_option_append(opt, optlen,
+ DHCP_OPTION_PARAMETER_REQUEST_LIST,
+ client->req_opts_size,
+ client->req_opts);
+ if (r < 0)
+ return r;
/* 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;
+ DHCP_MIN_OPTIONS_SIZE);
+ r = dhcp_option_append(opt, optlen,
+ DHCP_OPTION_MAXIMUM_MESSAGE_SIZE,
+ 2, &max_size);
+ if (r < 0)
+ return r;
}
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;
+ optlen = DHCP_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);
+ err = client_message_init(client, &discover->dhcp, DHCP_DISCOVER,
+ secs, &opt, &optlen);
if (err < 0)
return err;
if (err < 0)
return err;
- client_append_ip_headers(discover, len);
+ dhcp_packet_append_ip_headers(discover, BOOTREQUEST, len);
err = dhcp_network_send_raw_socket(client->fd, &client->link,
discover, len);
+ log_dhcp_client(client, "DISCOVER");
+
return err;
}
int err;
uint8_t *opt;
- optlen = DHCP_CLIENT_MIN_OPTIONS_SIZE;
+ optlen = DHCP_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);
+ err = client_message_init(client, &request->dhcp, DHCP_REQUEST, secs,
+ &opt, &optlen);
if (err < 0)
return err;
if (client->state == DHCP_STATE_RENEWING) {
err = dhcp_network_send_udp_socket(client->fd,
client->lease->server_address,
+ DHCP_PORT_SERVER,
&request->dhcp,
len - DHCP_IP_UDP_SIZE);
} else {
- client_append_ip_headers(request, len);
+ dhcp_packet_append_ip_headers(request, BOOTREQUEST, len);
err = dhcp_network_send_raw_socket(client->fd, &client->link,
request, len);
}
+ log_dhcp_client(client, "REQUEST");
+
return err;
}
static uint16_t client_update_secs(sd_dhcp_client *client, usec_t time_now)
{
- client->secs = (time_now - client->start_time) / USEC_PER_SEC;
+ client->secs = ((time_now - client->start_time) / USEC_PER_SEC) ? : 1;
return client->secs;
}
switch (client->state) {
case DHCP_STATE_RENEWING:
- time_left = (client->lease->t2 - client->lease->t1)/2;
+ time_left = (client->lease->t2 - client->lease->t1) / 2;
if (time_left < 60)
time_left = 60;
case DHCP_STATE_REBINDING:
- time_left = (client->lease->lifetime - client->lease->t2)/2;
+ time_left = (client->lease->lifetime - client->lease->t2) / 2;
if (time_left < 60)
time_left = 60;
next_timeout += (random_u32() & 0x1fffff);
- r = sd_event_add_monotonic(client->event, next_timeout,
+ client->timeout_resend = sd_event_source_unref(client->timeout_resend);
+
+ r = sd_event_add_monotonic(client->event,
+ &client->timeout_resend,
+ next_timeout,
10 * USEC_PER_MSEC,
- client_timeout_resend, client,
- &client->timeout_resend);
+ client_timeout_resend, client);
if (r < 0)
goto error;
- r = sd_event_source_set_priority(client->timeout_resend, client->event_priority);
+ r = sd_event_source_set_priority(client->timeout_resend,
+ client->event_priority);
if (r < 0)
goto error;
return 0;
}
-static int client_initialize_events(sd_dhcp_client *client, usec_t usec) {
+static int client_initialize_events(sd_dhcp_client *client,
+ sd_event_io_handler_t io_callback,
+ usec_t usec) {
int r;
assert(client);
assert(client->event);
- r = sd_event_add_io(client->event, client->fd, EPOLLIN,
- client_receive_message, client,
- &client->receive_message);
+ r = sd_event_add_io(client->event, &client->receive_message,
+ client->fd, EPOLLIN, io_callback,
+ client);
if (r < 0)
goto error;
- r = sd_event_source_set_priority(client->receive_message, client->event_priority);
+ r = sd_event_source_set_priority(client->receive_message,
+ client->event_priority);
if (r < 0)
goto error;
- r = sd_event_add_monotonic(client->event, usec, 0,
- client_timeout_resend, client,
- &client->timeout_resend);
+ client->timeout_resend = sd_event_source_unref(client->timeout_resend);
+
+ r = sd_event_add_monotonic(client->event,
+ &client->timeout_resend,
+ usec, 0,
+ client_timeout_resend, client);
if (r < 0)
goto error;
- r = sd_event_source_set_priority(client->timeout_resend, client->event_priority);
+ r = sd_event_source_set_priority(client->timeout_resend,
+ client->event_priority);
error:
if (r < 0)
void *userdata) {
sd_dhcp_client *client = userdata;
+ log_dhcp_client(client, "EXPIRED");
+
client_stop(client, DHCP_EVENT_EXPIRED);
return 0;
client->fd = r;
- return client_initialize_events(client, usec);
+ log_dhcp_client(client, "TIMEOUT T2");
+
+ return client_initialize_events(client, client_receive_message_raw,
+ usec);
}
-static int client_timeout_t1(sd_event_source *s, uint64_t usec, void *userdata) {
+static int client_timeout_t1(sd_event_source *s, uint64_t usec,
+ void *userdata) {
sd_dhcp_client *client = userdata;
int r;
client->attempt = 1;
r = dhcp_network_bind_udp_socket(client->index,
- client->lease->address);
+ client->lease->address,
+ DHCP_PORT_CLIENT);
if (r < 0) {
client_stop(client, r);
return 0;
client->fd = r;
- return client_initialize_events(client, usec);
-}
-
-static int client_verify_headers(sd_dhcp_client *client, DHCPPacket *message,
- size_t len) {
- size_t hdrlen;
+ log_dhcp_client(client, "TIMEOUT T1");
- 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;
-
- if (hdrlen + be16toh(message->udp.len) > len)
- return -EINVAL;
-
- if (message->udp.check) {
- message->ip.check = message->udp.len;
- message->ip.ttl = 0;
-
- if (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;
+ return client_initialize_events(client, client_receive_message_udp, usec);
}
-static int client_receive_offer(sd_dhcp_client *client, DHCPPacket *offer,
- size_t len) {
+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 = client_verify_headers(client, offer, len);
- if (r < 0)
- return r;
-
r = dhcp_lease_new(&lease);
if (r < 0)
return r;
- len = len - DHCP_IP_UDP_SIZE;
- r = dhcp_option_parse(&offer->dhcp, len, dhcp_lease_parse_options,
- lease);
+ r = dhcp_option_parse(offer, len, dhcp_lease_parse_options, lease);
if (r != DHCP_OFFER)
return -ENOMSG;
- lease->address = offer->dhcp.yiaddr;
+ lease->address = offer->yiaddr;
if (lease->address == INADDR_ANY ||
lease->server_address == INADDR_ANY ||
client->lease = lease;
lease = NULL;
+ log_dhcp_client(client, "OFFER");
+
return 0;
}
-static int client_receive_ack(sd_dhcp_client *client, const uint8_t *buf,
- size_t len) {
- DHCPPacket *ack;
- DHCPMessage *dhcp;
+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;
- 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;
- }
-
r = dhcp_lease_new(&lease);
if (r < 0)
return r;
- r = dhcp_option_parse(dhcp, len, dhcp_lease_parse_options, lease);
- if (r == DHCP_NAK)
+ 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->address = dhcp->yiaddr;
+ lease->address = ack->yiaddr;
if (lease->address == INADDR_ANY ||
lease->server_address == INADDR_ANY ||
client->lease = lease;
lease = NULL;
+ log_dhcp_client(client, "ACK");
+
return r;
}
if (next_timeout < usec)
return -EINVAL;
- r = sd_event_add_monotonic(client->event, next_timeout,
+ r = sd_event_add_monotonic(client->event,
+ &client->timeout_t1,
+ next_timeout,
10 * USEC_PER_MSEC,
- client_timeout_t1, client,
- &client->timeout_t1);
+ client_timeout_t1, client);
if (r < 0)
return r;
- r = sd_event_source_set_priority(client->timeout_t1, client->event_priority);
+ r = sd_event_source_set_priority(client->timeout_t1,
+ client->event_priority);
if (r < 0)
return r;
if (next_timeout < usec)
return -EINVAL;
- r = sd_event_add_monotonic(client->event, next_timeout,
+ r = sd_event_add_monotonic(client->event,
+ &client->timeout_t2,
+ next_timeout,
10 * USEC_PER_MSEC,
- client_timeout_t2, client,
- &client->timeout_t2);
+ client_timeout_t2, client);
if (r < 0)
return r;
- r = sd_event_source_set_priority(client->timeout_t2, client->event_priority);
+ r = sd_event_source_set_priority(client->timeout_t2,
+ client->event_priority);
if (r < 0)
return r;
if (next_timeout < usec)
return -EINVAL;
- r = sd_event_add_monotonic(client->event, next_timeout,
+ r = sd_event_add_monotonic(client->event,
+ &client->timeout_expire, next_timeout,
10 * USEC_PER_MSEC,
- client_timeout_expire, client,
- &client->timeout_expire);
+ client_timeout_expire, client);
if (r < 0)
return r;
- r = sd_event_source_set_priority(client->timeout_expire, client->event_priority);
+ r = sd_event_source_set_priority(client->timeout_expire,
+ client->event_priority);
if (r < 0)
return r;
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;
+static int client_handle_message(sd_dhcp_client *client, DHCPMessage *message,
+ int len, usec_t time_now) {
+ int r = 0, notify_event = 0;
- assert(s);
assert(client);
assert(client->event);
+ assert(message);
- len = read(fd, &buf, buflen);
- if (len < 0)
+ if (be32toh(message->xid) != client->xid)
return 0;
- r = sd_event_get_now_monotonic(client->event, &time_now);
- if (r < 0)
- goto error;
+ if (memcmp(&message->chaddr[0], &client->mac_addr.ether_addr_octet,
+ ETHER_ADDR_LEN))
+ return 0;
switch (client->state) {
case DHCP_STATE_SELECTING:
- message = (DHCPPacket *)&buf;
-
- if (client_receive_offer(client, message, len) >= 0) {
+ 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, time_now, 0,
+ r = sd_event_add_monotonic(client->event,
+ &client->timeout_resend,
+ time_now, 0,
client_timeout_resend,
- client,
- &client->timeout_resend);
+ client);
if (r < 0)
goto error;
- r = sd_event_source_set_priority(client->timeout_resend, client->event_priority);
+ r = sd_event_source_set_priority(client->timeout_resend,
+ client->event_priority);
if (r < 0)
goto error;
}
case DHCP_STATE_RENEWING:
case DHCP_STATE_REBINDING:
- r = client_receive_ack(client, buf, len);
+ r = client_handle_ack(client, message, len);
if (r == DHCP_EVENT_NO_LEASE)
goto error;
return 0;
}
+static int client_receive_message_udp(sd_event_source *s, int fd,
+ uint32_t revents, void *userdata) {
+ sd_dhcp_client *client = userdata;
+ uint8_t buf[sizeof(DHCPMessage) + DHCP_MIN_OPTIONS_SIZE];
+ int buflen = sizeof(buf);
+ int len, r = 0;
+ usec_t time_now;
+
+ assert(s);
+ assert(client);
+ assert(client->event);
+
+ len = read(fd, &buf, 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, (DHCPMessage *) buf, 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;
+ uint8_t buf[sizeof(DHCPPacket) + DHCP_MIN_OPTIONS_SIZE];
+ int buflen = sizeof(buf);
+ int len, r = 0;
+ DHCPPacket *packet;
+ usec_t time_now;
+
+ assert(s);
+ assert(client);
+ assert(client->event);
+
+ len = read(fd, &buf, buflen);
+ if (len < 0)
+ return 0;
+
+ packet = (DHCPPacket *) buf;
+
+ r = dhcp_packet_verify_headers(packet, BOOTREPLY, len);
+ if (r < 0) {
+ log_dhcp_client(client, "ignoring DHCP packet with invalid headers");
+ 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;
client->start_time = now(CLOCK_MONOTONIC);
client->secs = 0;
- return client_initialize_events(client, client->start_time);
+ log_dhcp_client(client, "STARTED");
+
+ return client_initialize_events(client, client_receive_message_raw,
+ client->start_time);
}
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 sd_dhcp_client_attach_event(sd_dhcp_client *client, sd_event *event,
+ int priority) {
int r;
assert_return(client, -EINVAL);
~ianmdlvl / elogind.git / blobdiff