/* VTun - Virtual Tunnel over TCP/IP network. Copyright (C) 1998-2008 Maxim Krasnyansky VTun has been derived from VPPP package by Maxim Krasnyansky. 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. */ /* * $Id: main.c,v 1.9.2.5 2012/07/08 05:32:57 mtbishop Exp $ */ #include "config.h" #include #include #include #include #include #include #include #include #ifdef HAVE_NETINET_IN_H #include #endif #include "vtun.h" #include "lib.h" #include "compat.h" /* Global options for the server and client */ struct vtun_opts vtun; struct vtun_host default_host; void write_pid(char *, char *); void reread_config(int sig); void usage(void); extern int optind,opterr,optopt; extern char *optarg; /* for the NATHack bit. Is our UDP session connected? */ int is_rmt_fd_connected=1; int main(int argc, char *argv[], char *env[]) { int svr, daemon, sock, dofork, fd, opt; struct vtun_host *host = NULL; struct sigaction sa; char *hst; /* Configure default settings */ svr = 0; daemon = 1; sock = 0; dofork = 1; vtun.cfg_file = VTUN_CONFIG_FILE; vtun.persist = -1; vtun.timeout = -1; vtun.sslauth = -1; vtun.transport_af = AF_INET; /* Dup strings because parser will try to free them */ vtun.ppp = strdup("/usr/sbin/pppd"); vtun.ifcfg = strdup("/sbin/ifconfig"); vtun.route = strdup("/sbin/route"); vtun.fwall = strdup("/sbin/ipchains"); vtun.iproute = strdup("/sbin/ip"); vtun.svr_name = NULL; vtun.svr_addr = NULL; vtun.bind_addr.port = -1; vtun.svr_type = -1; vtun.syslog = LOG_DAEMON; /* Initialize default host options */ memset(&default_host, 0, sizeof(default_host)); default_host.flags = VTUN_TTY | VTUN_TCP; default_host.multi = VTUN_MULTI_ALLOW; default_host.timeout = VTUN_CONNECT_TIMEOUT; default_host.ka_interval = 30; default_host.ka_maxfail = 4; default_host.loc_fd = default_host.rmt_fd = -1; #ifdef HAVE_SSL default_host.sslauth = 1; #else /* HAVE_SSL */ default_host.sslauth = 0; #endif /* HAVE_SSL */ /* Start logging to syslog and stderr */ openlog("vtund", LOG_PID | LOG_NDELAY | LOG_PERROR, LOG_DAEMON); while( (opt=getopt(argc,argv,"misf:P:L:t:npq46")) != EOF ){ switch(opt){ case 'm': if (mlockall(MCL_CURRENT | MCL_FUTURE) < 0) { perror("Unable to mlockall()"); exit(-1); } break; case 'i': vtun.svr_type = VTUN_INETD; case 's': svr = 1; break; case 'L': vtun.svr_addr = strdup(optarg); break; case 'P': vtun.bind_addr.port = atoi(optarg); break; case 'f': vtun.cfg_file = strdup(optarg); break; case 'n': daemon = 0; break; case 'p': vtun.persist = 1; break; case 't': vtun.timeout = atoi(optarg); break; case 'q': vtun.quiet = 1; break; case '4': vtun.transport_af = AF_INET; break; case '6': vtun.transport_af = AF_INET6; break; default: usage(); exit(1); } } reread_config(0); if (vtun.syslog != LOG_DAEMON) { /* Restart logging to syslog using specified facility */ closelog(); openlog("vtund", LOG_PID|LOG_NDELAY|LOG_PERROR, vtun.syslog); } clear_nat_hack_flags(svr); if(!svr){ if( argc - optind < 2 ){ usage(); exit(1); } hst = argv[optind++]; if( !(host = find_host(hst)) ){ vtun_syslog(LOG_ERR,"Host %s not found in %s", hst, vtun.cfg_file); exit(1); } vtun.svr_name = strdup(argv[optind]); } /* * Now fill uninitialized fields of the options structure * with default values. */ if(vtun.bind_addr.port == -1) vtun.bind_addr.port = VTUN_PORT; if(vtun.persist == -1) vtun.persist = 0; if(vtun.timeout == -1) vtun.timeout = VTUN_TIMEOUT; /* * Want to save behaviour from older version: stronger authentication * if compiled with --enable-ssl, weaker otherwise */ if(vtun.sslauth == -1) #ifdef HAVE_SSL vtun.sslauth = 1; #else /* HAVE_SSL */ vtun.sslauth = 0; #endif /* HAVE_SSL */ switch( vtun.svr_type ){ case -1: vtun.svr_type = VTUN_STAND_ALONE; break; case VTUN_INETD: sock = dup(0); dofork = 0; break; } if( daemon ){ if( dofork && fork() ) exit(0); /* Direct stdin,stdout,stderr to '/dev/null' */ fd = open("/dev/null", O_RDWR); close(0); dup(fd); close(1); dup(fd); close(2); dup(fd); close(fd); setsid(); chdir("/"); } if(svr){ memset(&sa,0,sizeof(sa)); sa.sa_handler=reread_config; sigaction(SIGHUP,&sa,NULL); init_title(argc,argv,env,"vtund[s]: "); if( vtun.svr_type == VTUN_STAND_ALONE ) write_pid("server", NULL); server(sock); } else { init_title(argc,argv,env,"vtund[c]: "); write_pid(host->host, vtun.svr_name); client(host); } closelog(); return 0; } /* * Very simple PID file creation function. Used by server. * Overrides existing file. Optionally adds session name and host name to the * pidfile name (this naming is very confusing, as the session is referred as * host most of the time) */ void write_pid(char *session, char *host) { char fn[1024]; FILE *f; if(session != NULL && host != NULL) { snprintf(fn, sizeof(fn), "%s/vtund.%s-%s.pid", VTUN_PID_DIR, session, host); } else if(session != NULL) { snprintf(fn, sizeof(fn), "%s/vtund.%s.pid", VTUN_PID_DIR, session); } else { snprintf(fn, sizeof(fn), "%s/vtund.pid", VTUN_PID_DIR); } /* Make sure the PID file is not there before opening it for writing. */ unlink(fn); if( !(f = fopen(fn, "w")) ) { syslog(LOG_ERR, "Can't write PID file %s: %s", fn, strerror(errno)); return; } fprintf(f,"%d",(int)getpid()); fclose(f); } void reread_config(int sig) { if( !read_config(vtun.cfg_file) ){ vtun_syslog(LOG_ERR,"No hosts defined"); exit(1); } } void usage(void) { printf("VTun ver %s\n", VTUN_VER); printf("Usage: \n"); printf(" Server:\n"); printf("\tvtund <-s> [-f file] [-P port] [-L local address]\n"); printf(" Client:\n"); /* I don't think these work. I'm disabling the suggestion - bish 20050601*/ printf("\tvtund [-f file] " /* [-P port] [-L local address] */ "[-p] [-m] [-t timeout] \n"); }