X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=networking%2Fudhcp%2Fdhcpd.c;h=3466312d1f511eeec24213b6f1fcc74387c8c679;hb=deabacdf91c6d1c3cfcdb4cd06780807193de81d;hp=56ddaa94273fa100b34d854bc83461796dfabfb9;hpb=9f4395c54e9e5507f2a59643f62bb42ef2601aab;p=oweals%2Fbusybox.git diff --git a/networking/udhcp/dhcpd.c b/networking/udhcp/dhcpd.c index 56ddaa942..3466312d1 100644 --- a/networking/udhcp/dhcpd.c +++ b/networking/udhcp/dhcpd.c @@ -1,3 +1,4 @@ +/* vi: set sw=4 ts=4: */ /* dhcpd.c * * udhcp Server @@ -6,291 +7,255 @@ * * Rewrite by Russ Dill 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. + * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. */ -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include - -#include "debug.h" +#include +#include "common.h" #include "dhcpd.h" -#include "arpping.h" -#include "socket.h" #include "options.h" -#include "files.h" -#include "leases.h" -#include "packet.h" -#include "serverpacket.h" -#include "pidfile.h" /* globals */ struct dhcpOfferedAddr *leases; -struct server_config_t server_config; -static int signal_pipe[2]; +/* struct server_config_t server_config is in bb_common_bufsiz1 */ -/* Exit and cleanup */ -static void exit_server(int retval) -{ - pidfile_delete(server_config.pidfile); - CLOSE_LOG(); - exit(retval); -} - -/* Signal handler */ -static void signal_handler(int sig) +int udhcpd_main(int argc, char **argv); +int udhcpd_main(int argc, char **argv) { - if (send(signal_pipe[1], &sig, sizeof(sig), MSG_DONTWAIT) < 0) { - LOG(LOG_ERR, "Could not send signal: %s", - strerror(errno)); - } -} - - -#ifdef COMBINED_BINARY -int udhcpd_main(int argc, char *argv[]) -#else -int main(int argc, char *argv[]) -#endif -{ fd_set rfds; struct timeval tv; - int server_socket = -1; - int bytes, retval; + int server_socket = -1, bytes, retval, max_sock; struct dhcpMessage packet; - unsigned char *state; - unsigned char *server_id, *requested; - u_int32_t server_id_align, requested_align; - unsigned long timeout_end; + uint8_t *state, *server_id, *requested; + uint32_t server_id_align, requested_align, static_lease_ip; + unsigned timeout_end; + unsigned num_ips; + unsigned opt; struct option_set *option; - struct dhcpOfferedAddr *lease; - int pid_fd; - int max_sock; - int sig; - unsigned long num_ips; - - OPEN_LOG("udhcpd"); - LOG(LOG_INFO, "udhcp server (v%s) started", VERSION); - - memset(&server_config, 0, sizeof(struct server_config_t)); - - if (argc < 2) - read_config(DHCPD_CONF_FILE); - else read_config(argv[1]); - - pid_fd = pidfile_acquire(server_config.pidfile); - pidfile_write_release(pid_fd); - - if ((option = find_option(server_config.options, DHCP_LEASE_TIME))) { + struct dhcpOfferedAddr *lease, static_lease; + + opt = getopt32(argv, "fS"); + argv += optind; + + if (!(opt & 1)) { /* no -f */ + bb_daemonize_or_rexec(0, argv); + logmode &= ~LOGMODE_STDIO; + } + + if (opt & 2) { /* -S */ + openlog(applet_name, LOG_PID, LOG_LOCAL0); + logmode |= LOGMODE_SYSLOG; + } + + /* Would rather not do read_config before daemonization - + * otherwise NOMMU machines will parse config twice */ + read_config(argv[0] ? argv[0] : DHCPD_CONF_FILE); + + /* Make sure fd 0,1,2 are open */ + bb_sanitize_stdio(); + /* Equivalent of doing a fflush after every \n */ + setlinebuf(stdout); + + /* Create pidfile */ + write_pidfile(server_config.pidfile); + /* if (!..) bb_perror_msg("cannot create pidfile %s", pidfile); */ + + bb_info_msg("%s (v%s) started", applet_name, BB_VER); + + option = find_option(server_config.options, DHCP_LEASE_TIME); + server_config.lease = LEASE_TIME; + if (option) { memcpy(&server_config.lease, option->data + 2, 4); server_config.lease = ntohl(server_config.lease); } - else server_config.lease = LEASE_TIME; - + /* Sanity check */ - num_ips = ntohl(server_config.end) - ntohl(server_config.start); + num_ips = server_config.end_ip - server_config.start_ip + 1; if (server_config.max_leases > num_ips) { - LOG(LOG_ERR, "max_leases value (%lu) not sane, setting to %lu instead", - server_config.max_leases, num_ips); + bb_error_msg("max_leases=%u is too big, setting to %u", + (unsigned)server_config.max_leases, num_ips); server_config.max_leases = num_ips; } - leases = xmalloc(sizeof(struct dhcpOfferedAddr) * server_config.max_leases); - memset(leases, 0, sizeof(struct dhcpOfferedAddr) * server_config.max_leases); + leases = xzalloc(server_config.max_leases * sizeof(*leases)); read_leases(server_config.lease_file); if (read_interface(server_config.interface, &server_config.ifindex, - &server_config.server, server_config.arp) < 0) - exit_server(1); - -#ifndef DEBUGGING - pid_fd = pidfile_acquire(server_config.pidfile); /* hold lock during fork. */ - if (daemon(0, 0) == -1) { - perror("fork"); - exit_server(1); + &server_config.server, server_config.arp)) { + retval = 1; + goto ret; } - pidfile_write_release(pid_fd); -#endif - - socketpair(AF_UNIX, SOCK_STREAM, 0, signal_pipe); - signal(SIGUSR1, signal_handler); - signal(SIGTERM, signal_handler); + /* Setup the signal pipe */ + udhcp_sp_setup(); - timeout_end = time(0) + server_config.auto_time; - while(1) { /* loop until universe collapses */ + timeout_end = monotonic_sec() + server_config.auto_time; + while (1) { /* loop until universe collapses */ - if (server_socket < 0) - if ((server_socket = listen_socket(INADDR_ANY, SERVER_PORT, server_config.interface)) < 0) { - LOG(LOG_ERR, "FATAL: couldn't create server socket, %s", strerror(errno)); - exit_server(0); - } + if (server_socket < 0) { + server_socket = listen_socket(/*INADDR_ANY,*/ SERVER_PORT, + server_config.interface); + } - FD_ZERO(&rfds); - FD_SET(server_socket, &rfds); - FD_SET(signal_pipe[0], &rfds); + max_sock = udhcp_sp_fd_set(&rfds, server_socket); if (server_config.auto_time) { - tv.tv_sec = timeout_end - time(0); + tv.tv_sec = timeout_end - monotonic_sec(); tv.tv_usec = 0; } + retval = 0; if (!server_config.auto_time || tv.tv_sec > 0) { - max_sock = server_socket > signal_pipe[0] ? server_socket : signal_pipe[0]; - retval = select(max_sock + 1, &rfds, NULL, NULL, + retval = select(max_sock + 1, &rfds, NULL, NULL, server_config.auto_time ? &tv : NULL); - } else retval = 0; /* If we already timed out, fall through */ - + } if (retval == 0) { write_leases(); - timeout_end = time(0) + server_config.auto_time; + timeout_end = monotonic_sec() + server_config.auto_time; continue; - } else if (retval < 0 && errno != EINTR) { - DEBUG(LOG_INFO, "error on select"); + } + if (retval < 0 && errno != EINTR) { + DEBUG("error on select"); continue; } - - if (FD_ISSET(signal_pipe[0], &rfds)) { - if (read(signal_pipe[0], &sig, sizeof(sig)) < 0) - continue; /* probably just EINTR */ - switch (sig) { - case SIGUSR1: - LOG(LOG_INFO, "Received a SIGUSR1"); - write_leases(); - /* why not just reset the timeout, eh */ - timeout_end = time(0) + server_config.auto_time; - continue; - case SIGTERM: - LOG(LOG_INFO, "Received a SIGTERM"); - exit_server(0); - } + + switch (udhcp_sp_read(&rfds)) { + case SIGUSR1: + bb_info_msg("Received a SIGUSR1"); + write_leases(); + /* why not just reset the timeout, eh */ + timeout_end = monotonic_sec() + server_config.auto_time; + continue; + case SIGTERM: + bb_info_msg("Received a SIGTERM"); + goto ret0; + case 0: break; /* no signal */ + default: continue; /* signal or error (probably EINTR) */ } - if ((bytes = get_packet(&packet, server_socket)) < 0) { /* this waits for a packet - idle */ + bytes = udhcp_get_packet(&packet, server_socket); /* this waits for a packet - idle */ + if (bytes < 0) { if (bytes == -1 && errno != EINTR) { - DEBUG(LOG_INFO, "error on read, %s, reopening socket", strerror(errno)); + DEBUG("error on read, %s, reopening socket", strerror(errno)); close(server_socket); server_socket = -1; } continue; } - if ((state = get_option(&packet, DHCP_MESSAGE_TYPE)) == NULL) { - DEBUG(LOG_ERR, "couldn't get option from packet, ignoring"); + state = get_option(&packet, DHCP_MESSAGE_TYPE); + if (state == NULL) { + bb_error_msg("cannot get option from packet, ignoring"); continue; } - - /* ADDME: look for a static lease */ - lease = find_lease_by_chaddr(packet.chaddr); + + /* Look for a static lease */ + static_lease_ip = getIpByMac(server_config.static_leases, &packet.chaddr); + + if (static_lease_ip) { + bb_info_msg("Found static lease: %x", static_lease_ip); + + memcpy(&static_lease.chaddr, &packet.chaddr, 16); + static_lease.yiaddr = static_lease_ip; + static_lease.expires = 0; + + lease = &static_lease; + } else { + lease = find_lease_by_chaddr(packet.chaddr); + } + switch (state[0]) { case DHCPDISCOVER: - DEBUG(LOG_INFO,"received DISCOVER"); - + DEBUG("Received DISCOVER"); + if (sendOffer(&packet) < 0) { - LOG(LOG_ERR, "send OFFER failed"); + bb_error_msg("send OFFER failed"); } - break; - case DHCPREQUEST: - DEBUG(LOG_INFO, "received REQUEST"); + break; + case DHCPREQUEST: + DEBUG("received REQUEST"); requested = get_option(&packet, DHCP_REQUESTED_IP); server_id = get_option(&packet, DHCP_SERVER_ID); if (requested) memcpy(&requested_align, requested, 4); if (server_id) memcpy(&server_id_align, server_id, 4); - - if (lease) { /*ADDME: or static lease */ + + if (lease) { if (server_id) { /* SELECTING State */ - DEBUG(LOG_INFO, "server_id = %08x", ntohl(server_id_align)); - if (server_id_align == server_config.server && requested && - requested_align == lease->yiaddr) { + DEBUG("server_id = %08x", ntohl(server_id_align)); + if (server_id_align == server_config.server && requested + && requested_align == lease->yiaddr + ) { sendACK(&packet, lease->yiaddr); } + } else if (requested) { + /* INIT-REBOOT State */ + if (lease->yiaddr == requested_align) + sendACK(&packet, lease->yiaddr); + else + sendNAK(&packet); + } else if (lease->yiaddr == packet.ciaddr) { + /* RENEWING or REBINDING State */ + sendACK(&packet, lease->yiaddr); } else { - if (requested) { - /* INIT-REBOOT State */ - if (lease->yiaddr == requested_align) - sendACK(&packet, lease->yiaddr); - else sendNAK(&packet); - } else { - /* RENEWING or REBINDING State */ - if (lease->yiaddr == packet.ciaddr) - sendACK(&packet, lease->yiaddr); - else { - /* don't know what to do!!!! */ - sendNAK(&packet); - } - } + /* don't know what to do!!!! */ + sendNAK(&packet); } - + /* what to do if we have no record of the client */ } else if (server_id) { /* SELECTING State */ } else if (requested) { /* INIT-REBOOT State */ - if ((lease = find_lease_by_yiaddr(requested_align))) { + lease = find_lease_by_yiaddr(requested_align); + if (lease) { if (lease_expired(lease)) { /* probably best if we drop this lease */ memset(lease->chaddr, 0, 16); /* make some contention for this address */ - } else sendNAK(&packet); - } else if (requested_align < server_config.start || - requested_align > server_config.end) { - sendNAK(&packet); - } /* else remain silent */ + } else + sendNAK(&packet); + } else { + uint32_t r = ntohl(requested_align); + if (r < server_config.start_ip + || r > server_config.end_ip + ) { + sendNAK(&packet); + } + /* else remain silent */ + } } else { - /* RENEWING or REBINDING State */ + /* RENEWING or REBINDING State */ } break; case DHCPDECLINE: - DEBUG(LOG_INFO,"received DECLINE"); + DEBUG("Received DECLINE"); if (lease) { memset(lease->chaddr, 0, 16); lease->expires = time(0) + server_config.decline_time; - } + } break; case DHCPRELEASE: - DEBUG(LOG_INFO,"received RELEASE"); - if (lease) lease->expires = time(0); + DEBUG("Received RELEASE"); + if (lease) + lease->expires = time(0); break; case DHCPINFORM: - DEBUG(LOG_INFO,"received INFORM"); + DEBUG("Received INFORM"); send_inform(&packet); - break; + break; default: - LOG(LOG_WARNING, "unsupported DHCP message (%02x) -- ignoring", state[0]); + bb_info_msg("Unsupported DHCP message (%02x) - ignoring", state[0]); } } - - return 0; + ret0: + retval = 0; + ret: + /*if (server_config.pidfile) - server_config.pidfile is never NULL */ + remove_pidfile(server_config.pidfile); + return retval; } -