/* acl.c - access control lists
Copyright (C) 2002, 2003, 2005, 2006, 2007 Free Software Foundation, Inc.
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, 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, Fifth Floor, Boston, MA 02110-1301, USA.
Written by Paul Eggert and Andreas Gruenbacher. */
#include <config.h>
#include "acl.h"
#include "acl-internal.h"
/* If DESC is a valid file descriptor use fchmod to change the
file's mode to MODE on systems that have fchown. On systems
that don't have fchown and if DESC is invalid, use chown on
NAME instead. */
int
chmod_or_fchmod (const char *name, int desc, mode_t mode)
{
if (HAVE_FCHMOD && desc != -1)
return fchmod (desc, mode);
else
return chmod (name, mode);
}
/* Copy access control lists from one file to another. If SOURCE_DESC is
a valid file descriptor, use file descriptor operations, else use
filename based operations on SRC_NAME. Likewise for DEST_DESC and
DEST_NAME.
If access control lists are not available, fchmod the target file to
MODE. Also sets the non-permission bits of the destination file
(S_ISUID, S_ISGID, S_ISVTX) to those from MODE if any are set.
System call return value semantics. */
int
copy_acl (const char *src_name, int source_desc, const char *dst_name,
int dest_desc, mode_t mode)
{
int ret;
#if USE_ACL && HAVE_ACL_GET_FILE && HAVE_ACL_SET_FILE && HAVE_ACL_FREE
/* POSIX 1003.1e (draft 17 -- abandoned) specific version. */
acl_t acl;
if (HAVE_ACL_GET_FD && source_desc != -1)
acl = acl_get_fd (source_desc);
else
acl = acl_get_file (src_name, ACL_TYPE_ACCESS);
if (acl == NULL)
{
if (ACL_NOT_WELL_SUPPORTED (errno))
return set_acl (dst_name, dest_desc, mode);
else
{
error (0, errno, "%s", quote (src_name));
return -1;
}
}
if (HAVE_ACL_SET_FD && dest_desc != -1)
ret = acl_set_fd (dest_desc, acl);
else
ret = acl_set_file (dst_name, ACL_TYPE_ACCESS, acl);
if (ret != 0)
{
int saved_errno = errno;
if (ACL_NOT_WELL_SUPPORTED (errno))
{
int n = acl_entries (acl);
acl_free (acl);
if (n == 3)
{
if (chmod_or_fchmod (dst_name, dest_desc, mode) != 0)
saved_errno = errno;
else
return 0;
}
else
chmod_or_fchmod (dst_name, dest_desc, mode);
}
else
{
acl_free (acl);
chmod_or_fchmod (dst_name, dest_desc, mode);
}
error (0, saved_errno, _("preserving permissions for %s"),
quote (dst_name));
return -1;
}
else
acl_free (acl);
if (mode & (S_ISUID | S_ISGID | S_ISVTX))
{
/* We did not call chmod so far, so the special bits have not yet
been set. */
if (chmod_or_fchmod (dst_name, dest_desc, mode) != 0)
{
error (0, errno, _("preserving permissions for %s"),
quote (dst_name));
return -1;
}
}
if (S_ISDIR (mode))
{
acl = acl_get_file (src_name, ACL_TYPE_DEFAULT);
if (acl == NULL)
{
error (0, errno, "%s", quote (src_name));
return -1;
}
if (acl_set_file (dst_name, ACL_TYPE_DEFAULT, acl))
{
error (0, errno, _("preserving permissions for %s"),
quote (dst_name));
acl_free (acl);
return -1;
}
else
acl_free (acl);
}
return 0;
#else
ret = chmod_or_fchmod (dst_name, dest_desc, mode);
if (ret != 0)
error (0, errno, _("preserving permissions for %s"), quote (dst_name));
return ret;
#endif
}
/* Set the access control lists of a file. If DESC is a valid file
descriptor, use file descriptor operations where available, else use
filename based operations on NAME. If access control lists are not
available, fchmod the target file to MODE. Also sets the
non-permission bits of the destination file (S_ISUID, S_ISGID, S_ISVTX)
to those from MODE if any are set. System call return value
semantics. */
int
set_acl (char const *name, int desc, mode_t mode)
{
#if USE_ACL && HAVE_ACL_SET_FILE && HAVE_ACL_FREE
/* POSIX 1003.1e draft 17 (abandoned) specific version. */
/* We must also have have_acl_from_text and acl_delete_def_file.
(acl_delete_def_file could be emulated with acl_init followed
by acl_set_file, but acl_set_file with an empty acl is
unspecified.) */
# ifndef HAVE_ACL_FROM_TEXT
# error Must have acl_from_text (see POSIX 1003.1e draft 17).
# endif
# ifndef HAVE_ACL_DELETE_DEF_FILE
# error Must have acl_delete_def_file (see POSIX 1003.1e draft 17).
# endif
acl_t acl;
int ret;
if (HAVE_ACL_FROM_MODE)
{
acl = acl_from_mode (mode);
if (!acl)
{
error (0, errno, "%s", quote (name));
return -1;
}
}
else
{
char acl_text[] = "u::---,g::---,o::---";
if (mode & S_IRUSR) acl_text[ 3] = 'r';
if (mode & S_IWUSR) acl_text[ 4] = 'w';
if (mode & S_IXUSR) acl_text[ 5] = 'x';
if (mode & S_IRGRP) acl_text[10] = 'r';
if (mode & S_IWGRP) acl_text[11] = 'w';
if (mode & S_IXGRP) acl_text[12] = 'x';
if (mode & S_IROTH) acl_text[17] = 'r';
if (mode & S_IWOTH) acl_text[18] = 'w';
if (mode & S_IXOTH) acl_text[19] = 'x';
acl = acl_from_text (acl_text);
if (!acl)
{
error (0, errno, "%s", quote (name));
return -1;
}
}
if (HAVE_ACL_SET_FD && desc != -1)
ret = acl_set_fd (desc, acl);
else
ret = acl_set_file (name, ACL_TYPE_ACCESS, acl);
if (ret != 0)
{
int saved_errno = errno;
acl_free (acl);
if (ACL_NOT_WELL_SUPPORTED (errno))
{
if (chmod_or_fchmod (name, desc, mode) != 0)
saved_errno = errno;
else
return 0;
}
error (0, saved_errno, _("setting permissions for %s"), quote (name));
return -1;
}
else
acl_free (acl);
if (S_ISDIR (mode) && acl_delete_def_file (name))
{
error (0, errno, _("setting permissions for %s"), quote (name));
return -1;
}
if (mode & (S_ISUID | S_ISGID | S_ISVTX))
{
/* We did not call chmod so far, so the special bits have not yet
been set. */
if (chmod_or_fchmod (name, desc, mode))
{
error (0, errno, _("preserving permissions for %s"), quote (name));
return -1;
}
}
return 0;
#else
int ret = chmod_or_fchmod (name, desc, mode);
if (ret)
error (0, errno, _("setting permissions for %s"), quote (name));
return ret;
#endif
}
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