return client;
}
-static int client_message_init(sd_dhcp_client *client, DHCPMessage *message,
- uint8_t type, size_t optlen, size_t *optoffset) {
+static int client_message_init(sd_dhcp_client *client, DHCPPacket **ret,
+ uint8_t type, size_t *_optlen, size_t *_optoffset) {
+ _cleanup_free_ DHCPPacket *packet;
+ size_t optlen, optoffset, size;
be16_t max_size;
int r;
assert(client);
assert(client->secs);
- assert(message);
- assert(optoffset);
+ assert(ret);
+ assert(_optlen);
+ assert(_optoffset);
assert(type == DHCP_DISCOVER || type == DHCP_REQUEST);
- r = dhcp_message_init(message, BOOTREQUEST, client->xid, type,
- message->options, optlen, optoffset);
+ optlen = DHCP_MIN_OPTIONS_SIZE;
+ size = sizeof(DHCPPacket) + optlen;
+
+ packet = malloc0(size);
+ if (!packet)
+ return -ENOMEM;
+
+ r = dhcp_message_init(&packet->dhcp, BOOTREQUEST, client->xid, type,
+ optlen, &optoffset);
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(client->secs);
+ packet->dhcp.secs = htobe16(client->secs);
+
+ /* RFC2132 section 4.1
+ A client that cannot receive unicast IP datagrams until its protocol
+ software has been configured with an IP address SHOULD set the
+ BROADCAST bit in the 'flags' field to 1 in any DHCPDISCOVER or
+ DHCPREQUEST messages that client sends. The BROADCAST bit will
+ provide a hint to the DHCP server and BOOTP relay agent to broadcast
+ any messages to the client on the client's subnet. */
+ packet->dhcp.flags = htobe16(0x8000);
/* RFC2132 section 4.1.1:
The client MUST include its hardware address in the ’chaddr’ field, if
necessary for delivery of DHCP reply messages.
*/
- memcpy(&message->chaddr, &client->client_id.mac_addr, ETH_ALEN);
+ memcpy(&packet->dhcp.chaddr, &client->client_id.mac_addr, ETH_ALEN);
/* Some DHCP servers will refuse to issue an DHCP lease if the Client
Identifier option is not set */
- r = dhcp_option_append(message->options, optlen, optoffset,
+ r = dhcp_option_append(&packet->dhcp, optlen, &optoffset, 0,
DHCP_OPTION_CLIENT_IDENTIFIER,
sizeof(client->client_id), &client->client_id);
if (r < 0)
it MUST include that list in any subsequent DHCPREQUEST
messages.
*/
- r = dhcp_option_append(message->options, optlen, optoffset,
+ r = dhcp_option_append(&packet->dhcp, optlen, &optoffset, 0,
DHCP_OPTION_PARAMETER_REQUEST_LIST,
client->req_opts_size, client->req_opts);
if (r < 0)
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_MIN_OPTIONS_SIZE);
- r = dhcp_option_append(message->options, optlen, optoffset,
+ max_size = htobe16(size);
+ r = dhcp_option_append(&packet->dhcp, optlen, &optoffset, 0,
DHCP_OPTION_MAXIMUM_MESSAGE_SIZE,
2, &max_size);
if (r < 0)
return r;
+ *_optlen = optlen;
+ *_optoffset = optoffset;
+ *ret = packet;
+ packet = NULL;
+
return 0;
}
static int client_send_discover(sd_dhcp_client *client) {
_cleanup_free_ DHCPPacket *discover = NULL;
- size_t optoffset, optlen, len;
+ size_t optoffset, optlen;
usec_t time_now;
int r;
* must always be strictly positive to deal with broken servers */
client->secs = ((time_now - client->start_time) / USEC_PER_SEC) ? : 1;
- optlen = DHCP_MIN_OPTIONS_SIZE;
- len = sizeof(DHCPPacket) + optlen;
-
- discover = malloc0(len);
- if (!discover)
- return -ENOMEM;
-
- r = client_message_init(client, &discover->dhcp, DHCP_DISCOVER,
- optlen, &optoffset);
+ r = client_message_init(client, &discover, DHCP_DISCOVER,
+ &optlen, &optoffset);
if (r < 0)
return r;
option to suggest the lease time it would like.
*/
if (client->last_addr != INADDR_ANY) {
- r = dhcp_option_append(discover->dhcp.options, optlen, &optoffset,
+ r = dhcp_option_append(&discover->dhcp, optlen, &optoffset, 0,
DHCP_OPTION_REQUESTED_IP_ADDRESS,
4, &client->last_addr);
if (r < 0)
return r;
}
- r = dhcp_option_append(discover->dhcp.options, optlen, &optoffset,
+ r = dhcp_option_append(&discover->dhcp, optlen, &optoffset, 0,
DHCP_OPTION_END, 0, NULL);
/* We currently ignore:
static int client_send_request(sd_dhcp_client *client) {
_cleanup_free_ DHCPPacket *request;
- size_t optoffset, optlen, len;
+ size_t optoffset, optlen;
int r;
- optlen = DHCP_MIN_OPTIONS_SIZE;
- len = sizeof(DHCPPacket) + optlen;
-
- request = malloc0(len);
- if (!request)
- return -ENOMEM;
-
- r = client_message_init(client, &request->dhcp, DHCP_REQUEST,
- optlen, &optoffset);
+ r = client_message_init(client, &request, DHCP_REQUEST,
+ &optlen, &optoffset);
if (r < 0)
return r;
filled in with the yiaddr value from the chosen DHCPOFFER.
*/
- r = dhcp_option_append(request->dhcp.options, optlen, &optoffset,
+ r = dhcp_option_append(&request->dhcp, optlen, &optoffset, 0,
DHCP_OPTION_SERVER_IDENTIFIER,
4, &client->lease->server_address);
if (r < 0)
return r;
- r = dhcp_option_append(request->dhcp.options, optlen, &optoffset,
+ r = dhcp_option_append(&request->dhcp, optlen, &optoffset, 0,
DHCP_OPTION_REQUESTED_IP_ADDRESS,
4, &client->lease->address);
if (r < 0)
option MUST be filled in with client’s notion of its previously
assigned address. ’ciaddr’ MUST be zero.
*/
- r = dhcp_option_append(request->dhcp.options, optlen, &optoffset,
+ r = dhcp_option_append(&request->dhcp, optlen, &optoffset, 0,
DHCP_OPTION_REQUESTED_IP_ADDRESS,
4, &client->last_addr);
if (r < 0)
return -EINVAL;
}
- r = dhcp_option_append(request->dhcp.options, optlen, &optoffset,
+ r = dhcp_option_append(&request->dhcp, optlen, &optoffset, 0,
DHCP_OPTION_END, 0, NULL);
if (r < 0)
return r;
assert(client);
r = ioctl(fd, FIONREAD, &buflen);
- if (r < 0 || buflen <= 0)
- buflen = sizeof(DHCPMessage) + DHCP_MIN_OPTIONS_SIZE;
+ if (r < 0)
+ return r;
+
+ if (buflen < 0)
+ /* this can't be right */
+ return -EIO;
message = malloc0(buflen);
if (!message)
len = read(fd, message, buflen);
if (len < 0) {
log_dhcp_client(client, "could not receive message from UDP "
- "socket: %s", strerror(errno));
+ "socket: %m");
return 0;
} else if ((size_t)len < sizeof(DHCPMessage))
return 0;
assert(client);
r = ioctl(fd, FIONREAD, &buflen);
- if (r < 0 || buflen <= 0)
- buflen = sizeof(DHCPPacket) + DHCP_MIN_OPTIONS_SIZE;
+ if (r < 0)
+ return r;
+
+ if (buflen < 0)
+ /* this can't be right */
+ return -EIO;
packet = malloc0(buflen);
if (!packet)
len = recvmsg(fd, &msg, 0);
if (len < 0) {
log_dhcp_client(client, "could not receive message from raw "
- "socket: %s", strerror(errno));
+ "socket: %m");
return 0;
} else if ((size_t)len < sizeof(DHCPPacket))
return 0;