ftpd.c

wu-ftpd类unix下的ftp服务器,可用于嵌入式系统

int fclose(FILE *);
#endif

static SIGNAL_TYPE alarm_signal(int sig)
{
}

static FILE *draconian_FILE = NULL;

static SIGNAL_TYPE draconian_alarm_signal(int sig)
{
    if (draconian_FILE != NULL) {
	fclose(draconian_FILE);
	draconian_FILE = NULL;
    }
}

static void socket_flush_wait(FILE *file)
{
#ifndef SUPPORT_BROKEN_CLIENTS
    char c;
    int fd = fileno(file);
    if (draconian_FILE != NULL)
	shutdown(fd, 1);
    if (draconian_FILE != NULL)
	read(fd, &c, 1);
/*
 * GAL - the read() here should be checked to ensure it returned 0 (indicating
 * EOF) or -1 (an error occurred).  Anything else (real data) is a protocol
 * error.
 */
#endif
}

int main(int argc, char **argv, char **envp)
{
#if defined(UNIXWARE) || defined(AIX)
    size_t addrlen;
#else
    int addrlen;
#endif
    int on = 1;
#ifdef IPTOS_LOWDELAY
    int tos;
#endif
    int c;
#ifndef INTERNAL_LS
    int which;
#endif
    extern int optopt;
    extern char *optarg;
    struct hostent *shp;
    struct aclmember *entry;
#ifdef VIRTUAL
#if defined(UNIXWARE) || defined(AIX)
    size_t virtual_len;
#else
    int virtual_len;
#endif
    struct sockaddr_in *virtual_ptr;
    struct sockaddr_in virtual_addr;
#endif
#ifndef DAEMON
    struct servent *serv;
#endif

#ifdef AUX
    setcompat(COMPAT_POSIX | COMPAT_BSDSETUGID);
#endif

    closelog();
#ifdef FACILITY
    openlog("ftpd", LOG_PID | LOG_NDELAY, FACILITY);
#else
    openlog("ftpd", LOG_PID);
#endif

#ifdef SecureWare
    setluid(1);			/* make sure there is a valid luid */
    set_auth_parameters(argc, argv);
    setreuid(0, 0);
#endif
#if defined(M_UNIX) && !defined(_M_UNIX)
    res_init();			/* bug in old (1.1.1) resolver     */
    _res.retrans = 20;		/* because of fake syslog in 3.2.2 */
    setlogmask(LOG_UPTO(LOG_INFO));
#endif

#ifndef DAEMON
    addrlen = sizeof(his_addr);
    if (getpeername(0, (struct sockaddr *) &his_addr, &addrlen) < 0) {
	syslog(LOG_ERR, "getpeername (%s): %m", argv[0]);
#ifndef DEBUG
	exit(1);
#endif
    }
    addrlen = sizeof(ctrl_addr);
    if (getsockname(0, (struct sockaddr *) &ctrl_addr, &addrlen) < 0) {
	syslog(LOG_ERR, "getsockname (%s): %m", argv[0]);
#ifndef DEBUG
	exit(1);
#endif
    }
#ifdef IPTOS_LOWDELAY
    tos = IPTOS_LOWDELAY;
    if (setsockopt(0, IPPROTO_IP, IP_TOS, (char *) &tos, sizeof(int)) < 0)
	    syslog(LOG_WARNING, "setsockopt (IP_TOS): %m");
#endif

    serv = getservbyname("ftp-data", "tcp");
    if (serv != NULL)
	data_source.sin_port = serv->s_port;
    else
	data_source.sin_port = htons(ntohs(ctrl_addr.sin_port) - 1);
#endif /* DAEMON */

#ifndef DAEMON
    while ((c = getopt(argc, argv, ":aAvdlLiIoP:qQr:t:T:u:wVWX")) != -1) {
#else /* DAEMON */
    while ((c = getopt(argc, argv, ":aAvdlLiIop:P:qQr:sSt:T:u:VwWX")) != -1) {
#endif /* DAEMON */
	switch (c) {

	case 'a':
	    use_accessfile = 1;
	    break;

	case 'A':
	    use_accessfile = 0;
	    break;

	case 'v':
	    debug = 1;
	    break;

	case 'd':
	    debug = 1;
	    break;

	case 'l':
	    logging = 1;
	    break;

	case 'L':
	    log_commands = 1;
	    break;

	case 'i':
	    log_incoming_xfers = 1;
	    break;

	case 'I':
	    disable_rfc931 = 1;
	    break;

	case 'o':
	    log_outbound_xfers = 1;
	    break;

	case 'q':
	    Bypass_PID_Files = 0;
	    break;

	case 'Q':
	    Bypass_PID_Files = 1;
	    break;

	case 'r':
	    if ((optarg != NULL) && (optarg[0] != '\0')) {
		RootDirectory = malloc(strlen(optarg) + 1);
		if (RootDirectory != NULL)
		    strcpy(RootDirectory, optarg);
	    }
	    break;

	case 'P':
	    data_source.sin_port = htons(atoi(optarg));
	    break;

#ifdef DAEMON
	case 'p':
	    daemon_port = atoi(optarg);
	    break;

	case 's':
	    be_daemon = 1;
	    break;

	case 'S':
	    be_daemon = 2;
	    break;
#endif /* DAEMON */

	case 't':
	    timeout_idle = atoi(optarg);
	    if (timeout_maxidle < timeout_idle)
		timeout_maxidle = timeout_idle;
	    break;

	case 'T':
	    timeout_maxidle = atoi(optarg);
	    if (timeout_idle > timeout_maxidle)
		timeout_idle = timeout_maxidle;
	    break;

	case 'u':
	    {
		unsigned int val = 0;

		while (*optarg && *optarg >= '0' && *optarg <= '9')
		    val = val * 8 + *optarg++ - '0';
		if (*optarg || val > 0777)
		    syslog(LOG_ERR, "bad value for -u");
		else
		    defumask = val;
		break;
	    }

	case 'V':
	    print_copyright();
	    exit(0);
	    /* NOTREACHED */
	case 'w':
	    wtmp_logging = 1;
	    break;

	case 'W':
	    wtmp_logging = 0;
	    break;

	case 'x':
	    syslogmsg = 2;
	    break;

	case 'X':
	    syslogmsg = 1;
	    break;

	case ':':
	    syslog(LOG_ERR, "option -%c requires an argument", optopt);
	    break;

	default:
	    syslog(LOG_ERR, "unknown option -%c ignored", optopt);
	    break;
	}
    }
    initsetproctitle(argc, argv, envp);
    (void) freopen(_PATH_DEVNULL, "w", stderr);

    /* Checking for random signals ... */
#ifdef NEED_SIGFIX
    sigemptyset(&block_sigmask);
#endif
#ifndef SIG_DEBUG
#ifdef SIGHUP
    (void) signal(SIGHUP, randomsig);
#ifdef NEED_SIGFIX
    sigaddset(&block_sigmask, SIGHUP);
#endif
#endif
#ifdef SIGINT
    (void) signal(SIGINT, randomsig);
#ifdef NEED_SIGFIX
    sigaddset(&block_sigmask, SIGINT);
#endif
#endif
#ifdef SIGQUIT
    (void) signal(SIGQUIT, randomsig);
#ifdef NEED_SIGFIX
    sigaddset(&block_sigmask, SIGQUIT);
#endif
#endif
#ifdef SIGILL
    (void) signal(SIGILL, randomsig);
#ifdef NEED_SIGFIX
    sigaddset(&block_sigmask, SIGILL);
#endif
#endif
#ifdef SIGTRAP
    (void) signal(SIGTRAP, randomsig);
#ifdef NEED_SIGFIX
    sigaddset(&block_sigmask, SIGTRAP);
#endif
#endif
#ifdef SIGIOT
    (void) signal(SIGIOT, randomsig);
#ifdef NEED_SIGFIX
    sigaddset(&block_sigmask, SIGIOT);
#endif
#endif
#ifdef SIGEMT
    (void) signal(SIGEMT, randomsig);
#ifdef NEED_SIGFIX
    sigaddset(&block_sigmask, SIGEMT);
#endif
#endif
#ifdef SIGFPE
    (void) signal(SIGFPE, randomsig);
#ifdef NEED_SIGFIX
    sigaddset(&block_sigmask, SIGFPE);
#endif
#endif
#ifdef SIGKILL
    (void) signal(SIGKILL, randomsig);
#ifdef NEED_SIGFIX
    sigaddset(&block_sigmask, SIGKILL);
#endif
#endif
#ifdef SIGBUS
    (void) signal(SIGBUS, randomsig);
#ifdef NEED_SIGFIX
    sigaddset(&block_sigmask, SIGBUS);
#endif
#endif
#ifdef SIGSEGV
    (void) signal(SIGSEGV, randomsig);
#ifdef NEED_SIGFIX
    sigaddset(&block_sigmask, SIGSEGV);
#endif
#endif
#ifdef SIGSYS
    (void) signal(SIGSYS, randomsig);
#ifdef NEED_SIGFIX
    sigaddset(&block_sigmask, SIGSYS);
#endif
#endif
#ifdef SIGALRM
    (void) signal(SIGALRM, randomsig);
#ifdef NEED_SIGFIX
    sigaddset(&block_sigmask, SIGALRM);
#endif
#endif
#ifdef SIGSTOP
    (void) signal(SIGSTOP, randomsig);
#ifdef NEED_SIGFIX
    sigaddset(&block_sigmask, SIGSTOP);
#endif
#endif
#ifdef SIGTSTP
    (void) signal(SIGTSTP, randomsig);
#ifdef NEED_SIGFIX
    sigaddset(&block_sigmask, SIGTSTP);
#endif
#endif
#ifdef SIGTTIN
    (void) signal(SIGTTIN, randomsig);
#ifdef NEED_SIGFIX
    sigaddset(&block_sigmask, SIGTTIN);
#endif
#endif
#ifdef SIGTTOU
    (void) signal(SIGTTOU, randomsig);
#ifdef NEED_SIGFIX
    sigaddset(&block_sigmask, SIGTTOU);
#endif
#endif
#ifdef SIGIO
    (void) signal(SIGIO, randomsig);
#ifdef NEED_SIGFIX
    sigaddset(&block_sigmask, SIGIO);
#endif
#endif
#ifdef SIGXCPU
    (void) signal(SIGXCPU, randomsig);
#ifdef NEED_SIGFIX
    sigaddset(&block_sigmask, SIGXCPU);
#endif
#endif
#ifdef SIGXFSZ
    (void) signal(SIGXFSZ, randomsig);
#ifdef NEED_SIGFIX
    sigaddset(&block_sigmask, SIGXFSZ);
#endif
#endif
#ifdef SIGWINCH
    (void) signal(SIGWINCH, randomsig);
#ifdef NEED_SIGFIX
    sigaddset(&block_sigmask, SIGWINCH);
#endif
#endif
#ifdef SIGVTALRM
    (void) signal(SIGVTALRM, randomsig);
#ifdef NEED_SIGFIX
    sigaddset(&block_sigmask, SIGVTALRM);
#endif
#endif
#ifdef SIGPROF
    (void) signal(SIGPROF, randomsig);
#ifdef NEED_SIGFIX
    sigaddset(&block_sigmask, SIGPROF);
#endif
#endif
#ifdef SIGUSR1
    (void) signal(SIGUSR1, randomsig);
#ifdef NEED_SIGFIX
    sigaddset(&block_sigmask, SIGUSR1);
#endif
#endif
#ifdef SIGUSR2
    (void) signal(SIGUSR2, randomsig);
#ifdef NEED_SIGFIX
    sigaddset(&block_sigmask, SIGUSR2);
#endif
#endif

#ifdef SIGPIPE
    (void) signal(SIGPIPE, lostconn);
#ifdef NEED_SIGFIX
    sigaddset(&block_sigmask, SIGPIPE);
#endif
#endif
#ifdef SIGCHLD
    (void) signal(SIGCHLD, SIG_IGN);
#ifdef NEED_SIGFIX
    sigaddset(&block_sigmask, SIGCHLD);
#endif
#endif

#ifdef SIGURG
    if (signal(SIGURG, myoob) == SIG_ERR)
	syslog(LOG_ERR, "signal: %m");
#ifdef NEED_SIGFIX
    sigaddset(&block_sigmask, SIGURG);
#endif
#endif
#endif /* SIG_DEBUG */

#ifdef VIRTUAL
    virtual_root[0] = '\0';
    virtual_banner[0] = '\0';
#endif

    setup_paths();

#ifdef OTHER_PASSWD
    strcpy(_path_passwd, "/etc/passwd");
#ifdef SHADOW_PASSWORD
    strcpy(_path_shadow, "/etc/shadow");
#endif
#endif

    access_init();

#ifdef DAEMON
    if (be_daemon != 0)
	do_daemon(argc, argv, envp);
    addrlen = sizeof(his_addr);
    if (getpeername(0, (struct sockaddr *) &his_addr, &addrlen) < 0) {
	syslog(LOG_ERR, "getpeername (%s): %m", argv[0]);
#ifndef DEBUG
	exit(1);
#endif
    }
    addrlen = sizeof(ctrl_addr);
    if (getsockname(0, (struct sockaddr *) &ctrl_addr, &addrlen) < 0) {
	syslog(LOG_ERR, "getsockname (%s): %m", argv[0]);
#ifndef DEBUG
	exit(1);
#endif
    }
#ifdef IPTOS_LOWDELAY
    tos = IPTOS_LOWDELAY;
    if (setsockopt(0, IPPROTO_IP, IP_TOS, (char *) &tos, sizeof(int)) < 0)
	    syslog(LOG_WARNING, "setsockopt (IP_TOS): %m");
#endif
    if (keepalive)
	if (setsockopt(0, SOL_SOCKET, SO_KEEPALIVE, (char *) &on, sizeof(on)) < 0)
	    syslog(LOG_ERR, "setsockopt SO_KEEPALIVE %m");

    data_source.sin_port = htons(ntohs(ctrl_addr.sin_port) - 1);
#endif /* DAEMON */

    /* Try to handle urgent data inline */
#ifdef SO_OOBINLINE
    if (setsockopt(0, SOL_SOCKET, SO_OOBINLINE, (char *) &on, sizeof(int)) < 0)
	    syslog(LOG_ERR, "setsockopt (SO_OOBINLINE): %m");
#endif

#ifdef  F_SETOWN
    if (fcntl(fileno(stdin), F_SETOWN, getpid()) == -1)
	syslog(LOG_ERR, "fcntl F_SETOWN: %m");
#elif defined(SIOCSPGRP)
    {
	int pid;
	pid = getpid();
	if (ioctl(fileno(stdin), SIOCSPGRP, &pid) == -1)
	    syslog(LOG_ERR, "ioctl SIOCSPGRP: %m");
    }
#endif

    if (RootDirectory != NULL) {
	if ((chroot(RootDirectory) < 0)
	    || (chdir("/") < 0)) {
	    syslog(LOG_ERR, "Cannot chroot to initial directory, aborting.");
	    exit(1);
	}
    }

#ifdef HAVE_LIBRESOLV
    /* initialize the resolver, and set global DNS variables */
    initialize_dns(&his_addr);
#endif

    dolog(&his_addr);
    /* Set up default state */
    data = -1;
    type = TYPE_A;
    form = FORM_N;
    stru = STRU_F;
    mode = MODE_S;
    tmpline[0] = '\0';
    yyerrorcalled = 0;

    entry = (struct aclmember *) NULL;
    if ((getaclentry("hostname", &entry)) && ARG0) {
	(void) strncpy(hostname, ARG0, sizeof(hostname));
	hostname[sizeof(hostname) - 1] = '\0';
    }
    else {
#ifdef HAVE_SYSINFO
	sysinfo(SI_HOSTNAME, hostname, sizeof(hostname));
#else
	(void) gethostname(hostname, sizeof(hostname));
#endif
/* set the FQDN here */
	shp = gethostbyname(hostname);
	if (shp != NULL) {
	    (void) strncpy(hostname, shp->h_name, sizeof(hostname));
	    hostname[sizeof(hostname) - 1] = '\0';
	}
    }