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-rw-r--r--networking/udhcp/clientpacket.c245
1 files changed, 0 insertions, 245 deletions
diff --git a/networking/udhcp/clientpacket.c b/networking/udhcp/clientpacket.c
deleted file mode 100644
index e377bd2..0000000
--- a/networking/udhcp/clientpacket.c
+++ /dev/null
@@ -1,245 +0,0 @@
-/* clientpacket.c
- *
- * Packet generation and dispatching functions for the DHCP client.
- *
- * 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 <string.h>
-#include <sys/socket.h>
-#include <features.h>
-#if __GLIBC__ >=2 && __GLIBC_MINOR >= 1
-#include <netpacket/packet.h>
-#include <net/ethernet.h>
-#else
-#include <asm/types.h>
-#include <linux/if_packet.h>
-#include <linux/if_ether.h>
-#endif
-#include <stdlib.h>
-#include <time.h>
-#include <unistd.h>
-#include <netinet/in.h>
-#include <arpa/inet.h>
-#include <fcntl.h>
-
-
-#include "dhcpd.h"
-#include "clientpacket.h"
-#include "options.h"
-#include "dhcpc.h"
-#include "common.h"
-
-
-/* Create a random xid */
-unsigned long random_xid(void)
-{
- static int initialized;
- if (!initialized) {
- int fd;
- unsigned long seed;
-
- fd = open("/dev/urandom", 0);
- if (fd < 0 || read(fd, &seed, sizeof(seed)) < 0) {
- LOG(LOG_WARNING, "Could not load seed from /dev/urandom: %m");
- seed = time(0);
- }
- if (fd >= 0) close(fd);
- srand(seed);
- initialized++;
- }
- return rand();
-}
-
-
-/* initialize a packet with the proper defaults */
-static void init_packet(struct dhcpMessage *packet, char type)
-{
- init_header(packet, type);
- memcpy(packet->chaddr, client_config.arp, 6);
- if (client_config.clientid)
- add_option_string(packet->options, client_config.clientid);
- if (client_config.hostname) add_option_string(packet->options, client_config.hostname);
- if (client_config.fqdn) add_option_string(packet->options, client_config.fqdn);
- add_option_string(packet->options, client_config.vendorclass);
-}
-
-
-/* Add a parameter request list for stubborn DHCP servers. Pull the data
- * from the struct in options.c. Don't do bounds checking here because it
- * goes towards the head of the packet. */
-static void add_requests(struct dhcpMessage *packet)
-{
- int end = end_option(packet->options);
- int i, len = 0;
-
- packet->options[end + OPT_CODE] = DHCP_PARAM_REQ;
- for (i = 0; dhcp_options[i].code; i++)
- if (dhcp_options[i].flags & OPTION_REQ)
- packet->options[end + OPT_DATA + len++] = dhcp_options[i].code;
- packet->options[end + OPT_LEN] = len;
- packet->options[end + OPT_DATA + len] = DHCP_END;
-
-}
-
-
-/* Broadcast a DHCP discover packet to the network, with an optionally requested IP */
-int send_discover(unsigned long xid, unsigned long requested)
-{
- struct dhcpMessage packet;
-
- init_packet(&packet, DHCPDISCOVER);
- packet.xid = xid;
- if (requested)
- add_simple_option(packet.options, DHCP_REQUESTED_IP, requested);
-
- add_requests(&packet);
- LOG(LOG_DEBUG, "Sending discover...");
- return raw_packet(&packet, INADDR_ANY, CLIENT_PORT, INADDR_BROADCAST,
- SERVER_PORT, MAC_BCAST_ADDR, client_config.ifindex);
-}
-
-
-/* Broadcasts a DHCP request message */
-int send_selecting(unsigned long xid, unsigned long server, unsigned long requested)
-{
- struct dhcpMessage packet;
- struct in_addr addr;
-
- init_packet(&packet, DHCPREQUEST);
- packet.xid = xid;
-
- add_simple_option(packet.options, DHCP_REQUESTED_IP, requested);
- add_simple_option(packet.options, DHCP_SERVER_ID, server);
-
- add_requests(&packet);
- addr.s_addr = requested;
- LOG(LOG_DEBUG, "Sending select for %s...", inet_ntoa(addr));
- return raw_packet(&packet, INADDR_ANY, CLIENT_PORT, INADDR_BROADCAST,
- SERVER_PORT, MAC_BCAST_ADDR, client_config.ifindex);
-}
-
-
-/* Unicasts or broadcasts a DHCP renew message */
-int send_renew(unsigned long xid, unsigned long server, unsigned long ciaddr)
-{
- struct dhcpMessage packet;
- int ret = 0;
-
- init_packet(&packet, DHCPREQUEST);
- packet.xid = xid;
- packet.ciaddr = ciaddr;
-
- add_requests(&packet);
- LOG(LOG_DEBUG, "Sending renew...");
- if (server)
- ret = kernel_packet(&packet, ciaddr, CLIENT_PORT, server, SERVER_PORT);
- else ret = raw_packet(&packet, INADDR_ANY, CLIENT_PORT, INADDR_BROADCAST,
- SERVER_PORT, MAC_BCAST_ADDR, client_config.ifindex);
- return ret;
-}
-
-
-/* Unicasts a DHCP release message */
-int send_release(unsigned long server, unsigned long ciaddr)
-{
- struct dhcpMessage packet;
-
- init_packet(&packet, DHCPRELEASE);
- packet.xid = random_xid();
- packet.ciaddr = ciaddr;
-
- add_simple_option(packet.options, DHCP_REQUESTED_IP, ciaddr);
- add_simple_option(packet.options, DHCP_SERVER_ID, server);
-
- LOG(LOG_DEBUG, "Sending release...");
- return kernel_packet(&packet, ciaddr, CLIENT_PORT, server, SERVER_PORT);
-}
-
-
-/* return -1 on errors that are fatal for the socket, -2 for those that aren't */
-int get_raw_packet(struct dhcpMessage *payload, int fd)
-{
- int bytes;
- struct udp_dhcp_packet packet;
- uint32_t source, dest;
- uint16_t check;
-
- memset(&packet, 0, sizeof(struct udp_dhcp_packet));
- bytes = read(fd, &packet, sizeof(struct udp_dhcp_packet));
- if (bytes < 0) {
- DEBUG(LOG_INFO, "couldn't read on raw listening socket -- ignoring");
- usleep(500000); /* possible down interface, looping condition */
- return -1;
- }
-
- if (bytes < (int) (sizeof(struct iphdr) + sizeof(struct udphdr))) {
- DEBUG(LOG_INFO, "message too short, ignoring");
- return -2;
- }
-
- if (bytes < ntohs(packet.ip.tot_len)) {
- DEBUG(LOG_INFO, "Truncated packet");
- return -2;
- }
-
- /* ignore any extra garbage bytes */
- bytes = ntohs(packet.ip.tot_len);
-
- /* Make sure its the right packet for us, and that it passes sanity checks */
- if (packet.ip.protocol != IPPROTO_UDP || packet.ip.version != IPVERSION ||
- packet.ip.ihl != sizeof(packet.ip) >> 2 || packet.udp.dest != htons(CLIENT_PORT) ||
- bytes > (int) sizeof(struct udp_dhcp_packet) ||
- ntohs(packet.udp.len) != (uint16_t) (bytes - sizeof(packet.ip))) {
- DEBUG(LOG_INFO, "unrelated/bogus packet");
- return -2;
- }
-
- /* check IP checksum */
- check = packet.ip.check;
- packet.ip.check = 0;
- if (check != checksum(&(packet.ip), sizeof(packet.ip))) {
- DEBUG(LOG_INFO, "bad IP header checksum, ignoring");
- return -1;
- }
-
- /* verify the UDP checksum by replacing the header with a psuedo header */
- source = packet.ip.saddr;
- dest = packet.ip.daddr;
- check = packet.udp.check;
- packet.udp.check = 0;
- memset(&packet.ip, 0, sizeof(packet.ip));
-
- packet.ip.protocol = IPPROTO_UDP;
- packet.ip.saddr = source;
- packet.ip.daddr = dest;
- packet.ip.tot_len = packet.udp.len; /* cheat on the psuedo-header */
- if (check && check != checksum(&packet, bytes)) {
- DEBUG(LOG_ERR, "packet with bad UDP checksum received, ignoring");
- return -2;
- }
-
- memcpy(payload, &(packet.data), bytes - (sizeof(packet.ip) + sizeof(packet.udp)));
-
- if (ntohl(payload->cookie) != DHCP_MAGIC) {
- LOG(LOG_ERR, "received bogus message (bad magic) -- ignoring");
- return -2;
- }
- DEBUG(LOG_INFO, "oooooh!!! got some!");
- return bytes - (sizeof(packet.ip) + sizeof(packet.udp));
-
-}
generated by cgit v1.1 at 2024-11-06 01:32:24 +0000