ftpd.c

早期freebsd实现

	if (data != -1)
		printf("     Data connection open\r\n");
	else if (pdata != -1) {
		printf("     in Passive mode");
		sin = &pasv_addr;
		goto printaddr;
	} else if (usedefault == 0) {
		printf("     PORT");
		sin = &data_dest;
printaddr:
		a = (u_char *) &sin->sin_addr;
		p = (u_char *) &sin->sin_port;
#define UC(b) (((int) b) & 0xff)
		printf(" (%d,%d,%d,%d,%d,%d)\r\n", UC(a[0]),
			UC(a[1]), UC(a[2]), UC(a[3]), UC(p[0]), UC(p[1]));
#undef UC
	} else
		printf("     No data connection\r\n");
	reply(211, "End of status");
}

void
fatal(s)
	char *s;
{

	reply(451, "Error in server: %s\n", s);
	reply(221, "Closing connection due to server error.");
	dologout(0);
	/* NOTREACHED */
}

void
#if __STDC__
reply(int n, const char *fmt, ...)
#else
reply(n, fmt, va_alist)
	int n;
	char *fmt;
        va_dcl
#endif
{
	va_list ap;
#if __STDC__
	va_start(ap, fmt);
#else
	va_start(ap);
#endif
	(void)printf("%d ", n);
	(void)vprintf(fmt, ap);
	(void)printf("\r\n");
	(void)fflush(stdout);
	if (debug) {
		syslog(LOG_DEBUG, "<--- %d ", n);
		vsyslog(LOG_DEBUG, fmt, ap);
	}
}

void
#if __STDC__
lreply(int n, const char *fmt, ...)
#else
lreply(n, fmt, va_alist)
	int n;
	char *fmt;
        va_dcl
#endif
{
	va_list ap;
#if __STDC__
	va_start(ap, fmt);
#else
	va_start(ap);
#endif
	(void)printf("%d- ", n);
	(void)vprintf(fmt, ap);
	(void)printf("\r\n");
	(void)fflush(stdout);
	if (debug) {
		syslog(LOG_DEBUG, "<--- %d- ", n);
		vsyslog(LOG_DEBUG, fmt, ap);
	}
}

static void
ack(s)
	char *s;
{

	reply(250, "%s command successful.", s);
}

void
nack(s)
	char *s;
{

	reply(502, "%s command not implemented.", s);
}

/* ARGSUSED */
void
yyerror(s)
	char *s;
{
	char *cp;

	if (cp = strchr(cbuf,'\n'))
		*cp = '\0';
	reply(500, "'%s': command not understood.", cbuf);
}

void
delete(name)
	char *name;
{
	struct stat st;

	LOGCMD("delete", name);
	if (stat(name, &st) < 0) {
		perror_reply(550, name);
		return;
	}
	if ((st.st_mode&S_IFMT) == S_IFDIR) {
		if (rmdir(name) < 0) {
			perror_reply(550, name);
			return;
		}
		goto done;
	}
	if (unlink(name) < 0) {
		perror_reply(550, name);
		return;
	}
done:
	ack("DELE");
}

void
cwd(path)
	char *path;
{

	if (chdir(path) < 0)
		perror_reply(550, path);
	else
		ack("CWD");
}

void
makedir(name)
	char *name;
{

	LOGCMD("mkdir", name);
	if (mkdir(name, 0777) < 0)
		perror_reply(550, name);
	else
		reply(257, "MKD command successful.");
}

void
removedir(name)
	char *name;
{

	LOGCMD("rmdir", name);
	if (rmdir(name) < 0)
		perror_reply(550, name);
	else
		ack("RMD");
}

void
pwd()
{
	char path[MAXPATHLEN + 1];

	if (getwd(path) == (char *)NULL)
		reply(550, "%s.", path);
	else
		reply(257, "\"%s\" is current directory.", path);
}

char *
renamefrom(name)
	char *name;
{
	struct stat st;

	if (stat(name, &st) < 0) {
		perror_reply(550, name);
		return ((char *)0);
	}
	reply(350, "File exists, ready for destination name");
	return (name);
}

void
renamecmd(from, to)
	char *from, *to;
{

	LOGCMD2("rename", from, to);
	if (rename(from, to) < 0)
		perror_reply(550, "rename");
	else
		ack("RNTO");
}

static void
dolog(sin)
	struct sockaddr_in *sin;
{
	struct hostent *hp = gethostbyaddr((char *)&sin->sin_addr,
		sizeof(struct in_addr), AF_INET);

	if (hp)
		(void) strncpy(remotehost, hp->h_name, sizeof(remotehost));
	else
		(void) strncpy(remotehost, inet_ntoa(sin->sin_addr),
		    sizeof(remotehost));
#ifdef SETPROCTITLE
	snprintf(proctitle, sizeof(proctitle), "%s: connected", remotehost);
	setproctitle(proctitle);
#endif /* SETPROCTITLE */

	if (logging)
		syslog(LOG_INFO, "connection from %s", remotehost);
}

/*
 * Record logout in wtmp file
 * and exit with supplied status.
 */
void
dologout(status)
	int status;
{

	if (logged_in) {
		(void) seteuid((uid_t)0);
		logwtmp(ttyline, "", "");
	}
	/* beware of flushing buffers after a SIGPIPE */
	_exit(status);
}

static void
myoob(signo)
	int signo;
{
	char *cp;

	/* only process if transfer occurring */
	if (!transflag)
		return;
	cp = tmpline;
	if (getline(cp, 7, stdin) == NULL) {
		reply(221, "You could at least say goodbye.");
		dologout(0);
	}
	upper(cp);
	if (strcmp(cp, "ABOR\r\n") == 0) {
		tmpline[0] = '\0';
		reply(426, "Transfer aborted. Data connection closed.");
		reply(226, "Abort successful");
		longjmp(urgcatch, 1);
	}
	if (strcmp(cp, "STAT\r\n") == 0) {
		if (file_size != (off_t) -1)
			reply(213, "Status: %qd of %qd bytes transferred",
			    byte_count, file_size);
		else
			reply(213, "Status: %qd bytes transferred", byte_count);
	}
}

/*
 * Note: a response of 425 is not mentioned as a possible response to
 *	the PASV command in RFC959. However, it has been blessed as
 *	a legitimate response by Jon Postel in a telephone conversation
 *	with Rick Adams on 25 Jan 89.
 */
void
passive()
{
	int len;
	char *p, *a;

	pdata = socket(AF_INET, SOCK_STREAM, 0);
	if (pdata < 0) {
		perror_reply(425, "Can't open passive connection");
		return;
	}
	pasv_addr = ctrl_addr;
	pasv_addr.sin_port = 0;
	(void) seteuid((uid_t)0);
	if (bind(pdata, (struct sockaddr *)&pasv_addr, sizeof(pasv_addr)) < 0) {
		(void) seteuid((uid_t)pw->pw_uid);
		goto pasv_error;
	}
	(void) seteuid((uid_t)pw->pw_uid);
	len = sizeof(pasv_addr);
	if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0)
		goto pasv_error;
	if (listen(pdata, 1) < 0)
		goto pasv_error;
	a = (char *) &pasv_addr.sin_addr;
	p = (char *) &pasv_addr.sin_port;

#define UC(b) (((int) b) & 0xff)

	reply(227, "Entering Passive Mode (%d,%d,%d,%d,%d,%d)", UC(a[0]),
		UC(a[1]), UC(a[2]), UC(a[3]), UC(p[0]), UC(p[1]));
	return;

pasv_error:
	(void) close(pdata);
	pdata = -1;
	perror_reply(425, "Can't open passive connection");
	return;
}

/*
 * Generate unique name for file with basename "local".
 * The file named "local" is already known to exist.
 * Generates failure reply on error.
 */
static char *
gunique(local)
	char *local;
{
	static char new[MAXPATHLEN];
	struct stat st;
	int count;
	char *cp;

	cp = strrchr(local, '/');
	if (cp)
		*cp = '\0';
	if (stat(cp ? local : ".", &st) < 0) {
		perror_reply(553, cp ? local : ".");
		return ((char *) 0);
	}
	if (cp)
		*cp = '/';
	(void) strcpy(new, local);
	cp = new + strlen(new);
	*cp++ = '.';
	for (count = 1; count < 100; count++) {
		(void)sprintf(cp, "%d", count);
		if (stat(new, &st) < 0)
			return (new);
	}
	reply(452, "Unique file name cannot be created.");
	return (NULL);
}

/*
 * Format and send reply containing system error number.
 */
void
perror_reply(code, string)
	int code;
	char *string;
{

	reply(code, "%s: %s.", string, strerror(errno));
}

static char *onefile[] = {
	"",
	0
};

void
send_file_list(whichf)
	char *whichf;
{
	struct stat st;
	DIR *dirp = NULL;
	struct dirent *dir;
	FILE *dout = NULL;
	char **dirlist, *dirname;
	int simple = 0;
	int freeglob = 0;
	glob_t gl;

	if (strpbrk(whichf, "~{[*?") != NULL) {
		int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_QUOTE|GLOB_TILDE;

		memset(&gl, 0, sizeof(gl));
		freeglob = 1;
		if (glob(whichf, flags, 0, &gl)) {
			reply(550, "not found");
			goto out;
		} else if (gl.gl_pathc == 0) {
			errno = ENOENT;
			perror_reply(550, whichf);
			goto out;
		}
		dirlist = gl.gl_pathv;
	} else {
		onefile[0] = whichf;
		dirlist = onefile;
		simple = 1;
	}

	if (setjmp(urgcatch)) {
		transflag = 0;
		goto out;
	}
	while (dirname = *dirlist++) {
		if (stat(dirname, &st) < 0) {
			/*
			 * If user typed "ls -l", etc, and the client
			 * used NLST, do what the user meant.
			 */
			if (dirname[0] == '-' && *dirlist == NULL &&
			    transflag == 0) {
				retrieve("/bin/ls %s", dirname);
				goto out;
			}
			perror_reply(550, whichf);
			if (dout != NULL) {
				(void) fclose(dout);
				transflag = 0;
				data = -1;
				pdata = -1;
			}
			goto out;
		}

		if (S_ISREG(st.st_mode)) {
			if (dout == NULL) {
				dout = dataconn("file list", (off_t)-1, "w");
				if (dout == NULL)
					goto out;
				transflag++;
			}
			fprintf(dout, "%s%s\n", dirname,
				type == TYPE_A ? "\r" : "");
			byte_count += strlen(dirname) + 1;
			continue;
		} else if (!S_ISDIR(st.st_mode))
			continue;

		if ((dirp = opendir(dirname)) == NULL)
			continue;

		while ((dir = readdir(dirp)) != NULL) {
			char nbuf[MAXPATHLEN];

			if (dir->d_name[0] == '.' && dir->d_namlen == 1)
				continue;
			if (dir->d_name[0] == '.' && dir->d_name[1] == '.' &&
			    dir->d_namlen == 2)
				continue;

			sprintf(nbuf, "%s/%s", dirname, dir->d_name);

			/*
			 * We have to do a stat to insure it's
			 * not a directory or special file.
			 */
			if (simple || (stat(nbuf, &st) == 0 &&
			    S_ISREG(st.st_mode))) {
				if (dout == NULL) {
					dout = dataconn("file list", (off_t)-1,
						"w");
					if (dout == NULL)
						goto out;
					transflag++;
				}
				if (nbuf[0] == '.' && nbuf[1] == '/')
					fprintf(dout, "%s%s\n", &nbuf[2],
						type == TYPE_A ? "\r" : "");
				else
					fprintf(dout, "%s%s\n", nbuf,
						type == TYPE_A ? "\r" : "");
				byte_count += strlen(nbuf) + 1;
			}
		}
		(void) closedir(dirp);
	}

	if (dout == NULL)
		reply(550, "No files found.");
	else if (ferror(dout) != 0)
		perror_reply(550, "Data connection");
	else
		reply(226, "Transfer complete.");

	transflag = 0;
	if (dout != NULL)
		(void) fclose(dout);
	data = -1;
	pdata = -1;
out:
	if (freeglob) {
		freeglob = 0;
		globfree(&gl);
	}
}

#ifdef SETPROCTITLE
/*
 * Clobber argv so ps will show what we're doing.  (Stolen from sendmail.)
 * Warning, since this is usually started from inetd.conf, it often doesn't
 * have much of an environment or arglist to overwrite.
 */
void
#if __STDC__
setproctitle(const char *fmt, ...)
#else
setproctitle(fmt, va_alist)
	char *fmt;
        va_dcl
#endif
{
	int i;
	va_list ap;
	char *p, *bp, ch;
	char buf[LINE_MAX];

#if __STDC__
	va_start(ap, fmt);
#else
	va_start(ap);
#endif
	(void)vsnprintf(buf, sizeof(buf), fmt, ap);

	/* make ps print our process name */
	p = Argv[0];
	*p++ = '-';

	i = strlen(buf);
	if (i > LastArgv - p - 2) {
		i = LastArgv - p - 2;
		buf[i] = '\0';
	}
	bp = buf;
	while (ch = *bp++)
		if (ch != '\n' && ch != '\r')
			*p++ = ch;
	while (p < LastArgv)
		*p++ = ' ';
}
#endif /* SETPROCTITLE */