sd-dhcp-server: add basic NAK support

This commit is contained in:
Tom Gundersen 2014-05-25 20:39:02 +02:00
parent 2dead8129f
commit bd57b45029
2 changed files with 36 additions and 7 deletions

View File

@ -303,7 +303,7 @@ static int server_message_init(sd_dhcp_server *server, DHCPPacket **ret,
assert(server);
assert(ret);
assert(_optoffset);
assert(IN_SET(type, DHCP_OFFER, DHCP_ACK));
assert(IN_SET(type, DHCP_OFFER, DHCP_ACK, DHCP_NAK));
packet = malloc0(sizeof(DHCPPacket) + req->max_optlen);
if (!packet)
@ -377,6 +377,22 @@ static int server_send_ack(sd_dhcp_server *server, DHCPRequest *req, be32_t addr
return 0;
}
static int server_send_nak(sd_dhcp_server *server, DHCPRequest *req) {
_cleanup_free_ DHCPPacket *packet = NULL;
size_t offset;
int r;
r = server_message_init(server, &packet, DHCP_NAK, &offset, req);
if (r < 0)
return r;
r = dhcp_server_send_packet(server, req, packet, DHCP_NAK, offset);
if (r < 0)
return r;
return 0;
}
static int parse_request(uint8_t code, uint8_t len, const uint8_t *option,
void *user_data) {
DHCPRequest *req = user_data;
@ -515,6 +531,7 @@ int dhcp_server_handle_message(sd_dhcp_server *server, DHCPMessage *message,
case DHCP_REQUEST:
{
be32_t address;
bool init_reboot = false;
/* see RFC 2131, section 4.3.2 */
@ -546,8 +563,9 @@ int dhcp_server_handle_message(sd_dhcp_server *server, DHCPMessage *message,
/* this MUST be zero */
return 0;
/* TODO: check if requested IP is correct, NAK if not */
/* TODO: check more carefully if IP is correct */
address = req->requested_ip;
init_reboot = true;
} else {
log_dhcp_server(server, "REQUEST (rebinding/renewing) (0x%x)",
be32toh(req->message->xid));
@ -576,8 +594,19 @@ int dhcp_server_handle_message(sd_dhcp_server *server, DHCPMessage *message,
be32toh(req->message->xid));
return DHCP_ACK;
}
} else
return 0;
} else if (init_reboot) {
r = server_send_nak(server, req);
if (r < 0) {
/* this only fails on critical errors */
log_dhcp_server(server, "could not send nak: %s",
strerror(-r));
return r;
} else {
log_dhcp_server(server, "NAK (0x%x)",
be32toh(req->message->xid));
return DHCP_NAK;
}
}
break;
}

View File

@ -150,7 +150,7 @@ static void test_message_handler(void) {
test.option_requested_ip.code = DHCP_OPTION_REQUESTED_IP_ADDRESS;
test.option_requested_ip.length = 4;
test.option_requested_ip.address = htobe32(0x12345678);
assert_se(dhcp_server_handle_message(server, (DHCPMessage*)&test, sizeof(test)) == 0);
assert_se(dhcp_server_handle_message(server, (DHCPMessage*)&test, sizeof(test)) == DHCP_NAK);
test.option_server_id.code = DHCP_OPTION_SERVER_IDENTIFIER;
test.option_server_id.length = 4;
test.option_server_id.address = htobe32(INADDR_LOOPBACK);
@ -159,8 +159,8 @@ static void test_message_handler(void) {
test.option_server_id.address = htobe32(0x12345678);
test.option_requested_ip.address = htobe32(INADDR_LOOPBACK + 3);
assert_se(dhcp_server_handle_message(server, (DHCPMessage*)&test, sizeof(test)) == 0);
test.option_server_id.address = htobe32(INADDR_LOOPBACK + 3);
test.option_requested_ip.address = htobe32(0x12345678);
test.option_server_id.address = htobe32(INADDR_LOOPBACK);
test.option_requested_ip.address = htobe32(INADDR_LOOPBACK + 30);
assert_se(dhcp_server_handle_message(server, (DHCPMessage*)&test, sizeof(test)) == 0);
}