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author | Mike Frysinger | 2006-03-23 23:44:29 +0000 |
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committer | Mike Frysinger | 2006-03-23 23:44:29 +0000 |
commit | 787140df3992ccc3ebdc09f6d2dcb584f580f49f (patch) | |
tree | 666fdb071676c676f52bdc204f6df801b17e7196 /networking/udhcp/clientpacket.c | |
parent | e0fe93759339a9e043cd0489f5bfabd59b5fcb78 (diff) | |
download | busybox-787140df3992ccc3ebdc09f6d2dcb584f580f49f.zip busybox-787140df3992ccc3ebdc09f6d2dcb584f580f49f.tar.gz |
remove in place of external link
Diffstat (limited to 'networking/udhcp/clientpacket.c')
-rw-r--r-- | networking/udhcp/clientpacket.c | 245 |
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)); - -} |