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/*
* ProFTPD - mod_sftp miscellaneous
* Copyright (c) 2010 TJ Saunders
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA.
*
* As a special exemption, TJ Saunders and other respective copyright holders
* give permission to link this program with OpenSSL, and distribute the
* resulting executable, without including the source code for OpenSSL in the
* source distribution.
*
* $Id: misc.c,v 1.2 2011/05/23 21:03:12 castaglia Exp $
*/
#include "mod_sftp.h"
#include "misc.h"
int sftp_misc_handle_chown(pr_fh_t *fh) {
struct stat st;
int res, xerrno;
/* session.fsgid defaults to -1, so chown(2) won't chgrp unless specifically
* requested via GroupOwner.
*/
if (session.fsuid != (uid_t) -1) {
PRIVS_ROOT
res = pr_fsio_fchown(fh, session.fsuid, session.fsgid);
xerrno = errno;
PRIVS_RELINQUISH
if (res < 0) {
(void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION,
"chown(%s) as root failed: %s", fh->fh_path, strerror(xerrno));
} else {
if (session.fsgid != (gid_t) -1) {
(void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION,
"root chown(%s) to UID %lu, GID %lu successful", fh->fh_path,
(unsigned long) session.fsuid, (unsigned long) session.fsgid);
} else {
(void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION,
"root chown(%s) to UID %lu successful", fh->fh_path,
(unsigned long) session.fsuid);
}
pr_fs_clear_cache();
pr_fsio_fstat(fh, &st);
/* The chmod happens after the chown because chown will remove the
* S{U,G}ID bits on some files (namely, directories); the subsequent
* chmod is used to restore those dropped bits. This makes it necessary
* to use root privs when doing the chmod as well (at least in the case
* of chown'ing the file via root privs) in order to ensure that the mode
* can be set (a file might be being "given away", and if root privs
* aren't used, the chmod() will fail because the old owner/session user
* doesn't have the necessary privileges to do so).
*/
PRIVS_ROOT
res = pr_fsio_fchmod(fh, st.st_mode);
xerrno = errno;
PRIVS_RELINQUISH
if (res < 0) {
(void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION,
"root chmod(%s) to %04o failed: %s", fh->fh_path,
(unsigned int) st.st_mode, strerror(xerrno));
} else {
(void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION,
"root chmod(%s) to %04o successful", fh->fh_path,
(unsigned int) st.st_mode);
}
}
} else if (session.fsgid != (gid_t) -1) {
register unsigned int i;
int use_root_privs = TRUE;
/* Check if session.fsgid is in session.gids. If not, use root privs. */
for (i = 0; i < session.gids->nelts; i++) {
gid_t *group_ids = session.gids->elts;
if (group_ids[i] == session.fsgid) {
use_root_privs = FALSE;
break;
}
}
if (use_root_privs) {
PRIVS_ROOT
}
res = pr_fsio_fchown(fh, (uid_t) -1, session.fsgid);
xerrno = errno;
if (use_root_privs) {
PRIVS_RELINQUISH
}
if (res < 0) {
(void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION,
"%schown(%s) failed: %s", use_root_privs ? "root " : "", fh->fh_path,
strerror(xerrno));
} else {
(void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION,
"%schown(%s) to GID %lu successful",
use_root_privs ? "root " : "", fh->fh_path,
(unsigned long) session.fsgid);
pr_fs_clear_cache();
pr_fsio_fstat(fh, &st);
if (use_root_privs) {
PRIVS_ROOT
}
res = pr_fsio_fchmod(fh, st.st_mode);
xerrno = errno;
if (use_root_privs) {
PRIVS_RELINQUISH
}
if (res < 0) {
(void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION,
"%schmod(%s) to %04o failed: %s", use_root_privs ? "root " : "",
fh->fh_path, (unsigned int) st.st_mode, strerror(xerrno));
}
}
}
return 0;
}
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