ftpcmd.y

wu-ftpd类unix下的ftp服务器,可用于嵌入式系统

		if (strncasecmp(passtxt, s, 5) == 0)
		    syslog(LOG_DEBUG, "command: %s", passtxt);
		else
		    syslog(LOG_DEBUG, "command: %s", s);
	    }
	    tmpline[0] = '\0';
	    return (s);
	}
	if (c == 0)
	    tmpline[0] = '\0';
    }
  retry:
    while ((c = getc(iop)) != EOF) {
#ifdef TRANSFER_COUNT
	byte_count_total++;
	byte_count_in++;
#endif
	c &= 0377;
	if (c == IAC) {
	    if ((c = getc(iop)) != EOF) {
#ifdef TRANSFER_COUNT
		byte_count_total++;
		byte_count_in++;
#endif
		c &= 0377;
		switch (c) {
		case WILL:
		case WONT:
		    c = getc(iop);
#ifdef TRANSFER_COUNT
		    byte_count_total++;
		    byte_count_in++;
#endif
		    printf("%c%c%c", IAC, DONT, 0377 & c);
		    (void) fflush(stdout);
		    continue;
		case DO:
		case DONT:
		    c = getc(iop);
#ifdef TRANSFER_COUNT
		    byte_count_total++;
		    byte_count_in++;
#endif
		    printf("%c%c%c", IAC, WONT, 0377 & c);
		    (void) fflush(stdout);
		    continue;
		case IAC:
		    break;
		default:
		    continue;	/* ignore command */
		}
	    }
	}
	*cs++ = c;
	if (--n <= 0 || c == '\n')
	    break;
    }

    if (c == EOF && cs == s) {
	if (ferror(iop) && (errno == EINTR))
	    goto retry;
	return (NULL);
    }

    *cs++ = '\0';
    if (debug) {
	if (strncasecmp(passtxt, s, 5) == 0)
	    syslog(LOG_DEBUG, "command: %s", passtxt);
	else
	    syslog(LOG_DEBUG, "command: %s", s);
    }
    return (s);
}

static void toolong(int a) /* signal that caused this function to be called */
{
    time_t now;

    reply(421,
	  "Timeout (%d seconds): closing control connection.", timeout_idle);
    (void) time(&now);
    if (logging) {
	syslog(LOG_INFO,
	       "User %s timed out after %d seconds at %.24s",
	       (pw ? pw->pw_name : "unknown"), timeout_idle, ctime(&now));
    }
    dologout(1);
}

int yylex(void)
{
    static int cpos, state;
    register char *cp, *cp2;
    register struct tab *p;
    int n;
    time_t now;
    char c = '\0';
    extern time_t limit_time;
    extern time_t login_time;

    for (;;) {
	switch (state) {

	case CMD:
	    yyerrorcalled = 0;

	    setproctitle("%s: IDLE", proctitle);

	    if (is_shutdown(!logged_in, 0) != 0) {
		reply(221, "Server shutting down.  Goodbye.");
		dologout(0);
	    }

	    time(&now);
	    if ((limit_time > 0) && (((now - login_time) / 60) > limit_time)) {
		reply(221, "Time limit reached.  Goodbye.");
		dologout(0);
	    }

#ifdef IGNORE_NOOP
	    if (!alarm_running) {
		(void) signal(SIGALRM, toolong);
		(void) alarm((unsigned) timeout_idle);
		alarm_running = 1;
	    }
#else
	    (void) signal(SIGALRM, toolong);
	    (void) alarm((unsigned) timeout_idle);
#endif
	    if (wu_getline(cbuf, sizeof(cbuf) - 1, stdin) == NULL) {
		(void) alarm(0);
		reply(221, "You could at least say goodbye.");
		dologout(0);
	    }
#ifndef IGNORE_NOOP
	    (void) alarm(0);
#endif
	    if ((cp = strchr(cbuf, '\r'))) {
		*cp++ = '\n';
		*cp = '\0';
	    }
	    if ((cp = strpbrk(cbuf, " \n")))
		cpos = cp - cbuf;
	    if (cpos == 0)
		cpos = 4;
	    c = cbuf[cpos];
	    cbuf[cpos] = '\0';
	    upper(cbuf);
#ifdef IGNORE_NOOP
	    if (strncasecmp(cbuf, "NOOP", 4) != 0) {
		(void) alarm(0);
		alarm_running = 0;
	    }
#endif
	    p = lookup(cmdtab, cbuf);
	    cbuf[cpos] = c;
	    if (strncasecmp(cbuf, "PASS", 4) != 0 &&
		strncasecmp(cbuf, "SITE GPASS", 10) != 0) {
		if ((cp = strchr(cbuf, '\n')))
		    *cp = '\0';
		setproctitle("%s: %s", proctitle, cbuf);
		if (cp)
		    *cp = '\n';
	    }
	    if (p != 0) {
		if (p->implemented == 0) {
		    nack(p->name);
		    longjmp(errcatch, 0);
		    /* NOTREACHED */
		}
		state = p->state;
		yylval.String = p->name;
		return (p->token);
	    }
	    break;

	case SITECMD:
	    if (cbuf[cpos] == ' ') {
		cpos++;
		return (SP);
	    }
	    cp = &cbuf[cpos];
	    if ((cp2 = strpbrk(cp, " \n")))
		cpos = cp2 - cbuf;
	    c = cbuf[cpos];
	    cbuf[cpos] = '\0';
	    upper(cp);
	    p = lookup(sitetab, cp);
	    cbuf[cpos] = c;
	    if (p != 0) {
#ifndef PARANOID		/* what GOOD is SITE *, anyways?!  _H */
		if (p->implemented == 0) {
#else
		if (1) {
		    syslog(LOG_WARNING, "refused SITE %s %s from %s of %s",
			   p->name, &cbuf[cpos],
			   anonymous ? guestpw : authuser, remoteident);
#endif /* PARANOID */
		    state = CMD;
		    nack(p->name);
		    longjmp(errcatch, 0);
		    /* NOTREACHED */
		}
		state = p->state;
		yylval.String = p->name;
		return (p->token);
	    }
	    state = CMD;
	    break;

	case OSTR:
	    if (cbuf[cpos] == '\n') {
		state = CMD;
		return (CRLF);
	    }
	    /* FALLTHROUGH */

	case STR1:
	case ZSTR1:
	  dostr1:
	    if (cbuf[cpos] == ' ') {
		cpos++;
		if (state == OSTR)
		    state = STR2;
		else
		    ++state;
		return (SP);
	    }
	    break;

	case ZSTR2:
	    if (cbuf[cpos] == '\n') {
		state = CMD;
		return (CRLF);
	    }
	    /* FALLTHROUGH */

	case STR2:
	    cp = &cbuf[cpos];
	    n = strlen(cp);
	    cpos += n - 1;
	    /*
	     * Make sure the string is nonempty and \n terminated.
	     */
	    if (n > 1 && cbuf[cpos] == '\n') {
		cbuf[cpos] = '\0';
		yylval.String = copy(cp);
		cbuf[cpos] = '\n';
		state = ARGS;
		return (STRING);
	    }
	    break;

	case NSTR:
	    if (cbuf[cpos] == ' ') {
		cpos++;
		return (SP);
	    }
	    if (isdigit(cbuf[cpos])) {
		cp = &cbuf[cpos];
		while (isdigit(cbuf[++cpos]));
		c = cbuf[cpos];
		cbuf[cpos] = '\0';
		yylval.Number = atoi(cp);
		cbuf[cpos] = c;
		state = STR1;
		return (NUMBER);
	    }
	    state = STR1;
	    goto dostr1;

	case STR3:
	    if (cbuf[cpos] == ' ') {
		cpos++;
		return (SP);
	    }

	    cp = &cbuf[cpos];
	    cp2 = strpbrk(cp, " \n");
	    if (cp2 != NULL) {
		c = *cp2;
		*cp2 = '\0';
	    }
	    n = strlen(cp);
	    cpos += n;
	    /*
	     * Make sure the string is nonempty and SP terminated.
	     */
	    if ((cp2 - cp) > 1) {
		yylval.String = copy(cp);
		cbuf[cpos] = c;
		state = OSTR;
		return (STRING);
	    }
	    break;

	case ARGS:
	    if (isdigit(cbuf[cpos])) {
		cp = &cbuf[cpos];
		while (isdigit(cbuf[++cpos]));
		c = cbuf[cpos];
		cbuf[cpos] = '\0';
		yylval.Number = atoi(cp);
		cbuf[cpos] = c;
		return (NUMBER);
	    }
	    switch (cbuf[cpos++]) {

	    case '\n':
		state = CMD;
		return (CRLF);

	    case ' ':
		return (SP);

	    case ',':
		return (COMMA);

	    case 'A':
	    case 'a':
		return (A);

	    case 'B':
	    case 'b':
		return (B);

	    case 'C':
	    case 'c':
		return (C);

	    case 'E':
	    case 'e':
		return (E);

	    case 'F':
	    case 'f':
		return (F);

	    case 'I':
	    case 'i':
		return (I);

	    case 'L':
	    case 'l':
		return (L);

	    case 'N':
	    case 'n':
		return (N);

	    case 'P':
	    case 'p':
		return (P);

	    case 'R':
	    case 'r':
		return (R);

	    case 'S':
	    case 's':
		return (S);

	    case 'T':
	    case 't':
		return (T);

	    }
	    break;

	default:
	    fatal("Unknown state in scanner.");
	}
	if (yyerrorcalled == 0) {
	    if ((cp = strchr(cbuf, '\n')) != NULL)
		*cp = '\0';
	    if (logged_in)
		reply(500, "'%s': command not understood.", cbuf);
	    else
		reply(530, "Please login with USER and PASS.");
	}
	state = CMD;
	longjmp(errcatch, 0);
    }
}

void upper(char *s)
{
    while (*s != '\0') {
	if (islower(*s))
	    *s = toupper(*s);
	s++;
    }
}

char *copy(char *s)
{
    char *p;

    p = (char *) malloc((unsigned) strlen(s) + 1);
    if (p == NULL)
	fatal("Ran out of memory.");
    (void) strcpy(p, s);
    return (p);
}

void help(struct tab *ctab, char *s)
{
    struct aclmember *entry = NULL;
    struct tab *c;
    size_t width, NCMDS;
    char *type;

    if (ctab == sitetab)
	type = "SITE ";
    else
	type = "";
    width = 0, NCMDS = 0;
    for (c = ctab; c->name != NULL; c++) {
	size_t len = strlen(c->name);

	if (len > width)
	    width = len;
	NCMDS++;
    }
    width = (width + 8) & ~7;
    if (s == 0) {
	register size_t i, j, w;
	size_t columns, lines;

	lreply(214, "The following %scommands are recognized %s.",
	       type, "(* =>'s unimplemented)");
	columns = 76 / width;
	if (columns == 0)
	    columns = 1;
	lines = (NCMDS + columns - 1) / columns;
	for (i = 0; i < lines; i++) {
	    char line[BUFSIZ], *ptr = line;
	    strcpy(ptr, "   ");
	    ptr += 3;
	    for (j = 0; j < columns; j++) {
		c = ctab + j * lines + i;
		(void) sprintf(ptr, "%s%c", c->name,
			       c->implemented ? ' ' : '*');
		w = strlen(c->name) + 1;
		ptr += w;
		if (c + lines >= &ctab[NCMDS])
		    break;
		while (w < width) {
		    *(ptr++) = ' ';
		    w++;
		}
	    }
	    *ptr = '\0';
	    lreply(0, "%s", line);
	}
	(void) fflush(stdout);
#ifdef VIRTUAL
	if (virtual_mode && !virtual_ftpaccess && virtual_email[0] != '\0')
	    reply(214, "Direct comments to %s.", virtual_email);
	else
#endif
	if ((getaclentry("email", &entry)) && ARG0)
	    reply(214, "Direct comments to %s.", ARG0);
	else
	    reply(214, "Direct comments to ftp-bugs@%s.", hostname);
	return;
    }
    upper(s);
    c = lookup(ctab, s);
    if (c == (struct tab *) NULL) {
	reply(502, "Unknown command %s.", s);
	return;
    }
    if (c->implemented)
	reply(214, "Syntax: %s%s %s", type, c->name, c->help);
    else
	reply(214, "%s%-*s\t%s; unimplemented.", type, width,
	      c->name, c->help);
}

void sizecmd(char *filename)
{
    switch (type) {
    case TYPE_L:
    case TYPE_I:{
	    struct stat stbuf;
	    if (stat(filename, &stbuf) < 0 ||
		(stbuf.st_mode & S_IFMT) != S_IFREG)
		reply(550, "%s: not a plain file.", filename);
	    else
#if OFFSET_SIZE == 8
		reply(213, "%qu", stbuf.st_size);
#else
#ifdef _AIX42
		reply(213, "%llu", stbuf.st_size);
#else
		reply(213, "%lu", stbuf.st_size);
#endif
#endif
	    break;
	}
    case TYPE_A:{
	    FILE *fin;
	    register int c;
	    register long count;
	    struct stat stbuf;
	    fin = fopen(filename, "r");
	    if (fin == NULL) {
		perror_reply(550, filename);
		return;
	    }
	    if (fstat(fileno(fin), &stbuf) < 0 ||
		(stbuf.st_mode & S_IFMT) != S_IFREG) {
		reply(550, "%s: not a plain file.", filename);
		(void) fclose(fin);
		return;
	    }

	    count = 0;
	    while ((c = getc(fin)) != EOF) {
		if (c == '\n')	/* will get expanded to \r\n */
		    count++;
		count++;
	    }
	    (void) fclose(fin);

	    reply(213, "%ld", count);
	    break;
	}
    default:
	reply(504, "SIZE not implemented for Type %c.", "?AEIL"[type]);
    }
}

void site_exec(char *cmd)
{
#ifdef PARANOID
    syslog(LOG_CRIT, "REFUSED SITE_EXEC (slipped through!!): %s", cmd);
#else
    char buf[MAXPATHLEN];
    char *sp = (char *) strchr(cmd, ' '), *slash, *t;
    FILE *cmdf;


    /* sanitize the command-string */

    if (sp == 0) {
	while ((slash = strchr(cmd, '/')) != 0)
	    cmd = slash + 1;
    }
    else {
	while (sp && (slash = (char *) strchr(cmd, '/'))
	       && (slash < sp))
	    cmd = slash + 1;
    }

    for (t = cmd; *t && !isspace(*t); t++) {
	if (isupper(*t)) {
	    *t = tolower(*t);
	}
    }

    /* build the command */
    if (strlen(_PATH_EXECPATH) + strlen(cmd) + 2 > sizeof(buf))
	return;
    sprintf(buf, "%s/%s", _PATH_EXECPATH, cmd);

    cmdf = ftpd_popen(buf, "r", 0);
    if (!cmdf) {
	perror_reply(550, cmd);
	if (log_commands)
	    syslog(LOG_INFO, "SITE EXEC (FAIL: %m): %s", cmd);
    }
    else {
	int lines = 0;
	int maxlines = 0;
	struct aclmember *entry = NULL;
	char class[1024];
	int maxfound = 0;
	int defmaxlines = 20;
	int which;

	(void) acl_getclass(class);
	while ((getaclentry("site-exec-max-lines", &entry)) && ARG0) {
	    if (ARG1)
		for (which = 1; (which < MAXARGS) && ARG[which]; which++) {
		    if (!strcasecmp(ARG[which], class)) {
			maxlines = atoi(ARG0);
			maxfound = 1;
		    }
		    if (!strcmp(ARG[which], "*"))
			defmaxlines = atoi(ARG0);
		}
	    else
		defmaxlines = atoi(ARG0);
	}
	if (!maxfound)
	    maxlines = defmaxlines;
	lreply(200, "%s", cmd);
	while (fgets(buf, sizeof buf, cmdf)) {
	    size_t len = strlen(buf);

	    if (len > 0 && buf[len - 1] == '\n')
		buf[--len] = '\0';
	    lreply(200, "%s", buf);
	    if (maxlines <= 0)
		++lines;
	    else if (++lines >= maxlines) {
		lreply(200, "*** Truncated ***");
		break;
	    }
	}
	reply(200, " (end of '%s')", cmd);
	if (log_commands)
	    syslog(LOG_INFO, "SITE EXEC (lines: %d): %s", lines, cmd);
	ftpd_pclose(cmdf);
    }
#endif /* PARANOID */
}

void alias(char *s)
{
    struct aclmember *entry = NULL;

    if (s != (char *) NULL) {
	while (getaclentry("alias", &entry) && ARG0 && ARG1 != NULL)
	    if (!strcmp(ARG0, s)) {
		reply(214, "%s is an alias for %s.", ARG0, ARG1);
		return;
	    }
	reply(502, "Unknown alias %s.", s);
	return;
    }

    lreply(214, "The following aliases are available.");

    while (getaclentry("alias", &entry) && ARG0 && ARG1 != NULL)
	lreply(0, "   %-8s %s", ARG0, ARG1);
    (void) fflush(stdout);

    reply(214, "");
}

void cdpath(void)
{
    struct aclmember *entry = NULL;

    lreply(214, "The cdpath is:");
    while (getaclentry("cdpath", &entry) && ARG0 != NULL)
	lreply(0, "  %s", ARG0);
    (void) fflush(stdout);
    reply(214, "");
}

void print_groups(void)
{
    gid_t groups[NGROUPS_MAX];
    int ngroups = 0;

    if ((ngroups = getgroups(NGROUPS_MAX, groups)) < 0) {
	return;
    }

    lreply(214, "Group membership is:");
    ngroups--;

    for (; ngroups >= 0; ngroups--)
	lreply(214, "  %d", groups[ngroups]);

    (void) fflush(stdout);
    reply(214, "");
}