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Diffstat (limited to 'usr/src/cmd/cmd-inet/usr.sbin/in.ftpd/realpath.c')
-rw-r--r--usr/src/cmd/cmd-inet/usr.sbin/in.ftpd/realpath.c361
1 files changed, 361 insertions, 0 deletions
diff --git a/usr/src/cmd/cmd-inet/usr.sbin/in.ftpd/realpath.c b/usr/src/cmd/cmd-inet/usr.sbin/in.ftpd/realpath.c
new file mode 100644
index 0000000000..b961f2e474
--- /dev/null
+++ b/usr/src/cmd/cmd-inet/usr.sbin/in.ftpd/realpath.c
@@ -0,0 +1,361 @@
+/*
+ * Copyright 2004 Sun Microsystems, Inc. All rights reserved.
+ * Use is subject to license terms.
+ */
+
+#pragma ident "%Z%%M% %I% %E% SMI"
+
+/****************************************************************************
+ Copyright (c) 1999,2000 WU-FTPD Development Group.
+ All rights reserved.
+
+ Portions Copyright (c) 1980, 1985, 1988, 1989, 1990, 1991, 1993, 1994
+ The Regents of the University of California.
+ Portions Copyright (c) 1993, 1994 Washington University in Saint Louis.
+ Portions Copyright (c) 1996, 1998 Berkeley Software Design, Inc.
+ Portions Copyright (c) 1989 Massachusetts Institute of Technology.
+ Portions Copyright (c) 1998 Sendmail, Inc.
+ Portions Copyright (c) 1983, 1995, 1996, 1997 Eric P. Allman.
+ Portions Copyright (c) 1997 by Stan Barber.
+ Portions Copyright (c) 1997 by Kent Landfield.
+ Portions Copyright (c) 1991, 1992, 1993, 1994, 1995, 1996, 1997
+ Free Software Foundation, Inc.
+
+ Use and distribution of this software and its source code are governed
+ by the terms and conditions of the WU-FTPD Software License ("LICENSE").
+
+ If you did not receive a copy of the license, it may be obtained online
+ at http://www.wu-ftpd.org/license.html.
+
+ $Id: realpath.c,v 1.11 2000/07/01 18:17:39 wuftpd Exp $
+
+****************************************************************************/
+/* Originally taken from FreeBSD 3.0's libc; adapted to handle chroot
+ * directories in BeroFTPD by Bernhard Rosenkraenzer
+ * <bero@beroftpd.unix.eu.org>
+ *
+ * Added super-user permissions so we can determine the real pathname even
+ * if the user cannot access the file. <lundberg+wuftpd@vr.net>
+ */
+#include "config.h"
+
+#include <sys/param.h>
+#include <sys/stat.h>
+
+#include <errno.h>
+#if defined(HAVE_FCNTL_H)
+#include <fcntl.h>
+#endif
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include "proto.h"
+
+#ifndef MAXSYMLINKS /* Workaround for Linux libc 4.x/5.x */
+#define MAXSYMLINKS 5
+#endif
+
+#ifndef HAVE_LSTAT
+#define lstat stat
+#endif
+
+char *wu_realpath(const char *path, char resolved_path[MAXPATHLEN], char *chroot_path)
+{
+ char *ptr;
+ char q[MAXPATHLEN];
+
+ fb_realpath(path, q);
+
+ if (chroot_path == NULL)
+ strcpy(resolved_path, q);
+ else {
+ strcpy(resolved_path, chroot_path);
+ if (q[0] != '/') {
+ if (strlen(resolved_path) + strlen(q) < MAXPATHLEN)
+ strcat(resolved_path, q);
+ else /* Avoid buffer overruns... */
+ return NULL;
+ }
+ else if (q[1] != '\0') {
+ for (ptr = q; *ptr != '\0'; ptr++);
+ if (ptr == resolved_path || *--ptr != '/') {
+ if (strlen(resolved_path) + strlen(q) < MAXPATHLEN)
+ strcat(resolved_path, q);
+ else /* Avoid buffer overruns... */
+ return NULL;
+ }
+ else {
+ if (strlen(resolved_path) + strlen(q) - 1 < MAXPATHLEN)
+ strcat(resolved_path, &q[1]);
+ else /* Avoid buffer overruns... */
+ return NULL;
+ }
+ }
+ }
+ return resolved_path;
+}
+
+/*
+ * char *fb_realpath(const char *path, char resolved_path[MAXPATHLEN]);
+ *
+ * Find the real name of path, by removing all ".", ".." and symlink
+ * components. Returns (resolved) on success, or (NULL) on failure,
+ * in which case the path which caused trouble is left in (resolved).
+ */
+char *fb_realpath(const char *path, char *resolved)
+{
+ struct stat sb;
+ int fd, n, rootd, serrno;
+ char *p, *q, wbuf[MAXPATHLEN];
+ int symlinks = 0;
+ int resultcode;
+#ifdef HAS_NO_FCHDIR
+/* AIX Has no fchdir() so we hope the getcwd() call doesn't overrun the buffer! */
+ char cwd[MAXPATHLEN + 1];
+ char *pcwd;
+#endif
+
+ /* Save the starting point. */
+ errno = 0;
+#ifdef HAS_NO_FCHDIR
+#ifdef HAVE_GETCWD
+ pcwd = getcwd(cwd, sizeof(cwd));
+#else
+ pcwd = getwd(cwd);
+#endif
+#else
+ fd = open(".", O_RDONLY);
+#endif
+ if (EACCES == errno) {
+ uid_t userid = geteuid();
+ access_priv_on(0);
+#ifdef HAS_NO_FCHDIR
+#ifdef HAVE_GETCWD
+ pcwd = getcwd(cwd, sizeof(cwd));
+#else
+ pcwd = getwd(cwd);
+#endif
+#else
+ fd = open(".", O_RDONLY);
+#endif
+ access_priv_off(userid);
+ }
+#ifdef HAS_NO_FCHDIR
+ if (pcwd == NULL)
+#else
+ if (fd < 0)
+#endif
+ {
+ (void) strcpy(resolved, ".");
+ return (NULL);
+ }
+
+ /*
+ * Find the dirname and basename from the path to be resolved.
+ * Change directory to the dirname component.
+ * lstat the basename part.
+ * if it is a symlink, read in the value and loop.
+ * if it is a directory, then change to that directory.
+ * get the current directory name and append the basename.
+ */
+ (void) strncpy(resolved, path, MAXPATHLEN - 1);
+ resolved[MAXPATHLEN - 1] = '\0';
+ loop:
+ q = strrchr(resolved, '/');
+ if (q != NULL) {
+ p = q + 1;
+ if (q == resolved)
+ q = "/";
+ else {
+ do {
+ --q;
+ } while (q > resolved && *q == '/');
+ q[1] = '\0';
+ q = resolved;
+ }
+ errno = 0;
+ resultcode = chdir(q);
+ if (EACCES == errno) {
+ uid_t userid = geteuid();
+ access_priv_on(0);
+ errno = 0;
+ resultcode = chdir(q);
+ access_priv_off(userid);
+ }
+ if (resultcode < 0)
+ goto err1;
+ }
+ else
+ p = resolved;
+
+ /* Deal with the last component. */
+ if (*p != '\0') {
+ errno = 0;
+ resultcode = lstat(p, &sb);
+ if (EACCES == errno) {
+ uid_t userid = geteuid();
+ access_priv_on(0);
+ errno = 0;
+ resultcode = lstat(p, &sb);
+ access_priv_off(userid);
+ }
+ if (resultcode == 0) {
+#ifdef HAVE_LSTAT
+ if (S_ISLNK(sb.st_mode)) {
+ if (++symlinks > MAXSYMLINKS) {
+ errno = ELOOP;
+ goto err1;
+ }
+ errno = 0;
+ {
+ size_t len = strlen(p);
+ char *tmp = calloc(len + 1, sizeof(char));
+ if (tmp == 0) {
+ serrno = errno;
+ goto err1;
+ }
+ strcpy(tmp, p);
+ p = tmp;
+ }
+ n = readlink(p, resolved, MAXPATHLEN);
+ if (EACCES == errno) {
+ uid_t userid = geteuid();
+ access_priv_on(0);
+ errno = 0;
+ n = readlink(p, resolved, MAXPATHLEN);
+ access_priv_off(userid);
+ }
+ if (n < 0) {
+ free(p);
+ goto err1;
+ }
+ free(p);
+ /* n should be less than MAXPATHLEN, but check to be safe */
+ if (n >= MAXPATHLEN)
+ n = MAXPATHLEN - 1;
+ resolved[n] = '\0';
+ goto loop;
+ }
+#endif /* HAVE_LSTAT */
+ if (S_ISDIR(sb.st_mode)) {
+ errno = 0;
+ resultcode = chdir(p);
+ if (EACCES == errno) {
+ uid_t userid = geteuid();
+ access_priv_on(0);
+ errno = 0;
+ resultcode = chdir(p);
+ access_priv_off(userid);
+ }
+ if (resultcode < 0)
+ goto err1;
+ p = "";
+ }
+ }
+ }
+
+ /*
+ * Save the last component name and get the full pathname of
+ * the current directory.
+ */
+ (void) strcpy(wbuf, p);
+ errno = 0;
+#ifdef HAVE_GETCWD
+ resultcode = getcwd(resolved, MAXPATHLEN) == NULL ? 0 : 1;
+#else
+ resultcode = getwd(resolved) == NULL ? 0 : 1;
+ if (resolved[MAXPATHLEN - 1] != '\0') {
+ resultcode = 0;
+ errno = ERANGE;
+ }
+#endif
+ if (EACCES == errno) {
+ uid_t userid = geteuid();
+ access_priv_on(0);
+ errno = 0;
+#ifdef HAVE_GETCWD
+ resultcode = getcwd(resolved, MAXPATHLEN) == NULL ? 0 : 1;
+#else
+ resultcode = getwd(resolved) == NULL ? 0 : 1;
+ if (resolved[MAXPATHLEN - 1] != '\0') {
+ resultcode = 0;
+ errno = ERANGE;
+ }
+#endif
+ access_priv_off(userid);
+ }
+ if (resultcode == 0)
+ goto err1;
+
+ /*
+ * Join the two strings together, ensuring that the right thing
+ * happens if the last component is empty, or the dirname is root.
+ */
+ if (resolved[0] == '/' && resolved[1] == '\0')
+ rootd = 1;
+ else
+ rootd = 0;
+
+ if (*wbuf) {
+ if (strlen(resolved) + strlen(wbuf) + !rootd + 1 > MAXPATHLEN) {
+ errno = ENAMETOOLONG;
+ goto err1;
+ }
+ if (rootd == 0)
+ (void) strcat(resolved, "/");
+ (void) strcat(resolved, wbuf);
+ }
+
+ /* Go back to where we came from. */
+ errno = 0;
+#ifdef HAS_NO_FCHDIR
+ resultcode = chdir(cwd);
+#else
+ resultcode = fchdir(fd);
+#endif
+ if (EACCES == errno) {
+ uid_t userid = geteuid();
+ access_priv_on(0);
+ errno = 0;
+#ifdef HAS_NO_FCHDIR
+ resultcode = chdir(cwd);
+#else
+ resultcode = fchdir(fd);
+#endif
+ access_priv_off(userid);
+ }
+ if (resultcode < 0) {
+ serrno = errno;
+ goto err2;
+ }
+
+#ifndef HAS_NO_FCHDIR
+ /* It's okay if the close fails, what's an fd more or less? */
+ (void) close(fd);
+#endif
+ return (resolved);
+
+ err1:serrno = errno;
+#ifdef HAS_NO_FCHDIR
+ (void) chdir(cwd);
+#else
+ (void) fchdir(fd);
+#endif
+ if (EACCES == errno) {
+ uid_t userid = geteuid();
+ access_priv_on(0);
+#ifdef HAS_NO_FCHDIR
+ (void) chdir(cwd);
+#else
+ (void) fchdir(fd);
+#endif
+ access_priv_off(userid);
+ }
+#ifdef HAS_NO_FCHDIR
+ err2:errno = serrno;
+#else
+ err2:(void) close(fd);
+ errno = serrno;
+#endif
+ return (NULL);
+}
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