diff options
Diffstat (limited to 'networking/udhcp/serverpacket.c')
-rw-r--r-- | networking/udhcp/serverpacket.c | 275 |
1 files changed, 0 insertions, 275 deletions
diff --git a/networking/udhcp/serverpacket.c b/networking/udhcp/serverpacket.c deleted file mode 100644 index fe880b4..0000000 --- a/networking/udhcp/serverpacket.c +++ /dev/null @@ -1,275 +0,0 @@ -/* serverpacket.c - * - * Construct and send DHCP server packets - * - * Russ Dill <Russ.Dill@asu.edu> July 2001 - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. - */ - -#include <sys/socket.h> -#include <netinet/in.h> -#include <arpa/inet.h> -#include <string.h> -#include <time.h> - -#include "common.h" -#include "serverpacket.h" -#include "dhcpd.h" -#include "options.h" -#include "static_leases.h" - -/* send a packet to giaddr using the kernel ip stack */ -static int send_packet_to_relay(struct dhcpMessage *payload) -{ - DEBUG(LOG_INFO, "Forwarding packet to relay"); - - return kernel_packet(payload, server_config.server, SERVER_PORT, - payload->giaddr, SERVER_PORT); -} - - -/* send a packet to a specific arp address and ip address by creating our own ip packet */ -static int send_packet_to_client(struct dhcpMessage *payload, int force_broadcast) -{ - uint8_t *chaddr; - uint32_t ciaddr; - - if (force_broadcast) { - DEBUG(LOG_INFO, "broadcasting packet to client (NAK)"); - ciaddr = INADDR_BROADCAST; - chaddr = MAC_BCAST_ADDR; - } else if (payload->ciaddr) { - DEBUG(LOG_INFO, "unicasting packet to client ciaddr"); - ciaddr = payload->ciaddr; - chaddr = payload->chaddr; - } else if (ntohs(payload->flags) & BROADCAST_FLAG) { - DEBUG(LOG_INFO, "broadcasting packet to client (requested)"); - ciaddr = INADDR_BROADCAST; - chaddr = MAC_BCAST_ADDR; - } else { - DEBUG(LOG_INFO, "unicasting packet to client yiaddr"); - ciaddr = payload->yiaddr; - chaddr = payload->chaddr; - } - return raw_packet(payload, server_config.server, SERVER_PORT, - ciaddr, CLIENT_PORT, chaddr, server_config.ifindex); -} - - -/* send a dhcp packet, if force broadcast is set, the packet will be broadcast to the client */ -static int send_packet(struct dhcpMessage *payload, int force_broadcast) -{ - int ret; - - if (payload->giaddr) - ret = send_packet_to_relay(payload); - else ret = send_packet_to_client(payload, force_broadcast); - return ret; -} - - -static void init_packet(struct dhcpMessage *packet, struct dhcpMessage *oldpacket, char type) -{ - init_header(packet, type); - packet->xid = oldpacket->xid; - memcpy(packet->chaddr, oldpacket->chaddr, 16); - packet->flags = oldpacket->flags; - packet->giaddr = oldpacket->giaddr; - packet->ciaddr = oldpacket->ciaddr; - add_simple_option(packet->options, DHCP_SERVER_ID, server_config.server); -} - - -/* add in the bootp options */ -static void add_bootp_options(struct dhcpMessage *packet) -{ - packet->siaddr = server_config.siaddr; - if (server_config.sname) - strncpy((char*)packet->sname, server_config.sname, sizeof(packet->sname) - 1); - if (server_config.boot_file) - strncpy((char*)packet->file, server_config.boot_file, sizeof(packet->file) - 1); -} - - -/* send a DHCP OFFER to a DHCP DISCOVER */ -int sendOffer(struct dhcpMessage *oldpacket) -{ - struct dhcpMessage packet; - struct dhcpOfferedAddr *lease = NULL; - uint32_t req_align, lease_time_align = server_config.lease; - uint8_t *req, *lease_time; - struct option_set *curr; - struct in_addr addr; - - uint32_t static_lease_ip; - - init_packet(&packet, oldpacket, DHCPOFFER); - - static_lease_ip = getIpByMac(server_config.static_leases, oldpacket->chaddr); - - /* ADDME: if static, short circuit */ - if(!static_lease_ip) - { - /* the client is in our lease/offered table */ - if ((lease = find_lease_by_chaddr(oldpacket->chaddr))) { - if (!lease_expired(lease)) - lease_time_align = lease->expires - time(0); - packet.yiaddr = lease->yiaddr; - - /* Or the client has a requested ip */ - } else if ((req = get_option(oldpacket, DHCP_REQUESTED_IP)) && - - /* Don't look here (ugly hackish thing to do) */ - memcpy(&req_align, req, 4) && - - /* and the ip is in the lease range */ - ntohl(req_align) >= ntohl(server_config.start) && - ntohl(req_align) <= ntohl(server_config.end) && - - !static_lease_ip && /* Check that its not a static lease */ - /* and is not already taken/offered */ - ((!(lease = find_lease_by_yiaddr(req_align)) || - - /* or its taken, but expired */ /* ADDME: or maybe in here */ - lease_expired(lease)))) { - packet.yiaddr = req_align; /* FIXME: oh my, is there a host using this IP? */ - - /* otherwise, find a free IP */ - } else { - /* Is it a static lease? (No, because find_address skips static lease) */ - packet.yiaddr = find_address(0); - - /* try for an expired lease */ - if (!packet.yiaddr) packet.yiaddr = find_address(1); - } - - if(!packet.yiaddr) { - LOG(LOG_WARNING, "no IP addresses to give -- OFFER abandoned"); - return -1; - } - - if (!add_lease(packet.chaddr, packet.yiaddr, server_config.offer_time)) { - LOG(LOG_WARNING, "lease pool is full -- OFFER abandoned"); - return -1; - } - - if ((lease_time = get_option(oldpacket, DHCP_LEASE_TIME))) { - memcpy(&lease_time_align, lease_time, 4); - lease_time_align = ntohl(lease_time_align); - if (lease_time_align > server_config.lease) - lease_time_align = server_config.lease; - } - - /* Make sure we aren't just using the lease time from the previous offer */ - if (lease_time_align < server_config.min_lease) - lease_time_align = server_config.lease; - } - /* ADDME: end of short circuit */ - else - { - /* It is a static lease... use it */ - packet.yiaddr = static_lease_ip; - } - - add_simple_option(packet.options, DHCP_LEASE_TIME, htonl(lease_time_align)); - - curr = server_config.options; - while (curr) { - if (curr->data[OPT_CODE] != DHCP_LEASE_TIME) - add_option_string(packet.options, curr->data); - curr = curr->next; - } - - add_bootp_options(&packet); - - addr.s_addr = packet.yiaddr; - LOG(LOG_INFO, "sending OFFER of %s", inet_ntoa(addr)); - return send_packet(&packet, 0); -} - - -int sendNAK(struct dhcpMessage *oldpacket) -{ - struct dhcpMessage packet; - - init_packet(&packet, oldpacket, DHCPNAK); - - DEBUG(LOG_INFO, "sending NAK"); - return send_packet(&packet, 1); -} - - -int sendACK(struct dhcpMessage *oldpacket, uint32_t yiaddr) -{ - struct dhcpMessage packet; - struct option_set *curr; - uint8_t *lease_time; - uint32_t lease_time_align = server_config.lease; - struct in_addr addr; - - init_packet(&packet, oldpacket, DHCPACK); - packet.yiaddr = yiaddr; - - if ((lease_time = get_option(oldpacket, DHCP_LEASE_TIME))) { - memcpy(&lease_time_align, lease_time, 4); - lease_time_align = ntohl(lease_time_align); - if (lease_time_align > server_config.lease) - lease_time_align = server_config.lease; - else if (lease_time_align < server_config.min_lease) - lease_time_align = server_config.lease; - } - - add_simple_option(packet.options, DHCP_LEASE_TIME, htonl(lease_time_align)); - - curr = server_config.options; - while (curr) { - if (curr->data[OPT_CODE] != DHCP_LEASE_TIME) - add_option_string(packet.options, curr->data); - curr = curr->next; - } - - add_bootp_options(&packet); - - addr.s_addr = packet.yiaddr; - LOG(LOG_INFO, "sending ACK to %s", inet_ntoa(addr)); - - if (send_packet(&packet, 0) < 0) - return -1; - - add_lease(packet.chaddr, packet.yiaddr, lease_time_align); - - return 0; -} - - -int send_inform(struct dhcpMessage *oldpacket) -{ - struct dhcpMessage packet; - struct option_set *curr; - - init_packet(&packet, oldpacket, DHCPACK); - - curr = server_config.options; - while (curr) { - if (curr->data[OPT_CODE] != DHCP_LEASE_TIME) - add_option_string(packet.options, curr->data); - curr = curr->next; - } - - add_bootp_options(&packet); - - return send_packet(&packet, 0); -} |