/* copy-acl.c - copy access control list from one file to another file
Copyright (C) 2002-2003, 2005-2008 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 3 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, see <http://www.gnu.org/licenses/>.
Written by Paul Eggert, Andreas Grünbacher, and Bruno Haible. */
#include <config.h>
#include "acl.h"
#include "acl-internal.h"
#include "gettext.h"
#define _(msgid) gettext (msgid)
/* 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
DST_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.
Return 0 if successful.
Return -2 and set errno for an error relating to the source file.
Return -1 and set errno for an error relating to the destination file. */
static int
qcopy_acl (const char *src_name, int source_desc, const char *dst_name,
int dest_desc, mode_t mode)
{
#if USE_ACL && HAVE_ACL_GET_FILE
/* POSIX 1003.1e (draft 17 -- abandoned) specific version. */
/* Linux, FreeBSD, MacOS X, IRIX, Tru64 */
# if MODE_INSIDE_ACL
/* Linux, FreeBSD, IRIX, Tru64 */
acl_t acl;
int ret;
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 qset_acl (dst_name, dest_desc, mode);
else
return -2;
}
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) && !acl_access_nontrivial (acl))
{
acl_free (acl);
return chmod_or_fchmod (dst_name, dest_desc, mode);
}
else
{
acl_free (acl);
chmod_or_fchmod (dst_name, dest_desc, mode);
errno = saved_errno;
return -1;
}
}
else
acl_free (acl);
if (mode & (S_ISUID | S_ISGID | S_ISVTX))
{
/* We did not call chmod so far, and either the mode and the ACL are
separate or special bits are to be set which don't fit into ACLs. */
if (chmod_or_fchmod (dst_name, dest_desc, mode) != 0)
return -1;
}
if (S_ISDIR (mode))
{
acl = acl_get_file (src_name, ACL_TYPE_DEFAULT);
if (acl == NULL)
return -2;
if (acl_set_file (dst_name, ACL_TYPE_DEFAULT, acl))
{
int saved_errno = errno;
acl_free (acl);
errno = saved_errno;
return -1;
}
else
acl_free (acl);
}
return 0;
# else /* !MODE_INSIDE_ACL */
/* MacOS X */
# if !HAVE_ACL_TYPE_EXTENDED
# error Must have ACL_TYPE_EXTENDED
# endif
/* On MacOS X, acl_get_file (name, ACL_TYPE_ACCESS)
and acl_get_file (name, ACL_TYPE_DEFAULT)
always return NULL / EINVAL. You have to use
acl_get_file (name, ACL_TYPE_EXTENDED)
or acl_get_fd (open (name, ...))
to retrieve an ACL.
On the other hand,
acl_set_file (name, ACL_TYPE_ACCESS, acl)
and acl_set_file (name, ACL_TYPE_DEFAULT, acl)
have the same effect as
acl_set_file (name, ACL_TYPE_EXTENDED, acl):
Each of these calls sets the file's ACL. */
acl_t acl;
int ret;
if (HAVE_ACL_GET_FD && source_desc != -1)
acl = acl_get_fd (source_desc);
else
acl = acl_get_file (src_name, ACL_TYPE_EXTENDED);
if (acl == NULL)
{
if (ACL_NOT_WELL_SUPPORTED (errno))
return qset_acl (dst_name, dest_desc, mode);
else
return -2;
}
if (HAVE_ACL_SET_FD && dest_desc != -1)
ret = acl_set_fd (dest_desc, acl);
else
ret = acl_set_file (dst_name, ACL_TYPE_EXTENDED, acl);
if (ret != 0)
{
int saved_errno = errno;
if (ACL_NOT_WELL_SUPPORTED (errno) && !acl_extended_nontrivial (acl))
{
acl_free (acl);
return chmod_or_fchmod (dst_name, dest_desc, mode);
}
else
{
acl_free (acl);
chmod_or_fchmod (dst_name, dest_desc, mode);
errno = saved_errno;
return -1;
}
}
else
acl_free (acl);
/* Since !MODE_INSIDE_ACL, we have to call chmod explicitly. */
return chmod_or_fchmod (dst_name, dest_desc, mode);
# endif
#elif USE_ACL && defined GETACL /* Solaris, Cygwin, not HP-UX */
# if defined ACL_NO_TRIVIAL
/* Solaris 10 (newer version), which has additional API declared in
<sys/acl.h> (acl_t) and implemented in libsec (acl_set, acl_trivial,
acl_fromtext, ...). */
int ret;
acl_t *aclp = NULL;
ret = (source_desc < 0
? acl_get (src_name, ACL_NO_TRIVIAL, &aclp)
: facl_get (source_desc, ACL_NO_TRIVIAL, &aclp));
if (ret != 0 && errno != ENOSYS)
return -2;
ret = qset_acl (dst_name, dest_desc, mode);
if (ret != 0)
return -1;
if (aclp)
{
ret = (dest_desc < 0
? acl_set (dst_name, aclp)
: facl_set (dest_desc, aclp));
if (ret != 0)
{
int saved_errno = errno;
acl_free (aclp);
errno = saved_errno;
return -1;
}
acl_free (aclp);
}
return 0;
# else /* Solaris, Cygwin, general case */
/* Solaris 2.5 through Solaris 10, Cygwin, and contemporaneous versions
of Unixware. The acl() call returns the access and default ACL both
at once. */
# ifdef ACE_GETACL
int ace_count;
ace_t *ace_entries;
# endif
int count;
aclent_t *entries;
int did_chmod;
int saved_errno;
int ret;
# ifdef ACE_GETACL
/* Solaris also has a different variant of ACLs, used in ZFS and NFSv4
file systems (whereas the other ones are used in UFS file systems).
There is an API
pathconf (name, _PC_ACL_ENABLED)
fpathconf (desc, _PC_ACL_ENABLED)
that allows to determine which of the two kinds of ACLs is supported
for the given file. But some file systems may implement this call
incorrectly, so better not use it.
When fetching the source ACL, we simply fetch both ACL types.
When setting the destination ACL, we try either ACL types, assuming
that the kernel will translate the ACL from one form to the other.
(See in <http://docs.sun.com/app/docs/doc/819-2241/6n4huc7ia?l=en&a=view>
the description of ENOTSUP.) */
for (;;)
{
ace_count = (source_desc != -1
? facl (source_desc, ACE_GETACLCNT, 0, NULL)
: acl (src_name, ACE_GETACLCNT, 0, NULL));
if (ace_count < 0)
{
if (errno == ENOSYS || errno == EINVAL)
{
ace_count = 0;
ace_entries = NULL;
break;
}
else
return -2;
}
if (ace_count == 0)
{
ace_entries = NULL;
break;
}
ace_entries = (ace_t *) malloc (ace_count * sizeof (ace_t));
if (ace_entries == NULL)
{
errno = ENOMEM;
return -2;
}
if ((source_desc != -1
? facl (source_desc, ACE_GETACL, ace_count, ace_entries)
: acl (src_name, ACE_GETACL, ace_count, ace_entries))
== ace_count)
break;
/* Huh? The number of ACL entries changed since the last call.
Repeat. */
}
# endif
for (;;)
{
count = (source_desc != -1
? facl (source_desc, GETACLCNT, 0, NULL)
: acl (src_name, GETACLCNT, 0, NULL));
if (count < 0)
{
if (errno == ENOSYS || errno == ENOTSUP)
{
count = 0;
entries = NULL;
break;
}
else
return -2;
}
if (count == 0)
{
entries = NULL;
break;
}
entries = (aclent_t *) malloc (count * sizeof (aclent_t));
if (entries == NULL)
{
errno = ENOMEM;
return -2;
}
if ((source_desc != -1
? facl (source_desc, GETACL, count, entries)
: acl (src_name, GETACL, count, entries))
== count)
break;
/* Huh? The number of ACL entries changed since the last call.
Repeat. */
}
/* Is there an ACL of either kind? */
# ifdef ACE_GETACL
if (ace_count == 0)
# endif
if (count == 0)
return qset_acl (dst_name, dest_desc, mode);
did_chmod = 0; /* set to 1 once the mode bits in 0777 have been set */
saved_errno = 0; /* the first non-ignorable error code */
if (!MODE_INSIDE_ACL)
{
/* On Cygwin, it is necessary to call chmod before acl, because
chmod can change the contents of the ACL (in ways that don't
change the allowed accesses, but still visible). */
if (chmod_or_fchmod (dst_name, dest_desc, mode) != 0)
saved_errno = errno;
did_chmod = 1;
}
/* If both ace_entries and entries are available, try SETACL before
ACE_SETACL, because SETACL cannot fail with ENOTSUP whereas ACE_SETACL
can. */
if (count > 0)
{
ret = (dest_desc != -1
? facl (dest_desc, SETACL, count, entries)
: acl (dst_name, SETACL, count, entries));
if (ret < 0 && saved_errno == 0)
{
saved_errno = errno;
if (errno == ENOSYS && !acl_nontrivial (count, entries))
saved_errno = 0;
}
else
did_chmod = 1;
}
free (entries);
# ifdef ACE_GETACL
if (ace_count > 0)
{
ret = (dest_desc != -1
? facl (dest_desc, ACE_SETACL, ace_count, ace_entries)
: acl (dst_name, ACE_SETACL, ace_count, ace_entries));
if (ret < 0 && saved_errno == 0)
{
saved_errno = errno;
if ((errno == ENOSYS || errno == EINVAL || errno == ENOTSUP)
&& !acl_ace_nontrivial (ace_count, ace_entries))
saved_errno = 0;
}
}
free (ace_entries);
# endif
if (MODE_INSIDE_ACL
&& did_chmod <= ((mode & (S_ISUID | S_ISGID | S_ISVTX)) ? 1 : 0))
{
/* We did not call chmod so far, and either the mode and the ACL are
separate or special bits are to be set which don't fit into ACLs. */
if (chmod_or_fchmod (dst_name, dest_desc, mode) != 0)
{
if (saved_errno == 0)
saved_errno = errno;
}
}
if (saved_errno)
{
errno = saved_errno;
return -1;
}
return 0;
# endif
#elif USE_ACL && HAVE_GETACL /* HP-UX */
int count;
struct acl_entry entries[NACLENTRIES];
int ret;
for (;;)
{
count = (source_desc != -1
? fgetacl (source_desc, 0, NULL)
: getacl (src_name, 0, NULL));
if (count < 0)
{
if (errno == ENOSYS || errno == EOPNOTSUPP)
{
count = 0;
break;
}
else
return -2;
}
if (count == 0)
break;
if (count > NACLENTRIES)
/* If NACLENTRIES cannot be trusted, use dynamic memory allocation. */
abort ();
if ((source_desc != -1
? fgetacl (source_desc, count, entries)
: getacl (src_name, count, entries))
== count)
break;
/* Huh? The number of ACL entries changed since the last call.
Repeat. */
}
if (count == 0)
return qset_acl (dst_name, dest_desc, mode);
ret = (dest_desc != -1
? fsetacl (dest_desc, count, entries)
: setacl (dst_name, count, entries));
if (ret < 0)
{
int saved_errno = errno;
if (errno == ENOSYS || errno == EOPNOTSUPP)
{
struct stat source_statbuf;
if ((source_desc != -1
? fstat (source_desc, &source_statbuf)
: stat (src_name, &source_statbuf)) == 0)
{
if (!acl_nontrivial (count, entries, &source_statbuf))
return chmod_or_fchmod (dst_name, dest_desc, mode);
}
else
saved_errno = errno;
}
chmod_or_fchmod (dst_name, dest_desc, mode);
errno = saved_errno;
return -1;
}
if (mode & (S_ISUID | S_ISGID | S_ISVTX))
{
/* We did not call chmod so far, and either the mode and the ACL are
separate or special bits are to be set which don't fit into ACLs. */
return chmod_or_fchmod (dst_name, dest_desc, mode);
}
return 0;
#elif USE_ACL && HAVE_ACLX_GET && 0 /* AIX */
/* TODO */
#elif USE_ACL && HAVE_STATACL /* older AIX */
union { struct acl a; char room[4096]; } u;
int ret;
if ((source_desc != -1
? fstatacl (source_desc, STX_NORMAL, &u.a, sizeof (u))
: statacl (src_name, STX_NORMAL, &u.a, sizeof (u)))
< 0)
return -2;
ret = (dest_desc != -1
? fchacl (dest_desc, &u.a, u.a.acl_len)
: chacl (dst_name, &u.a, u.a.acl_len));
if (ret < 0)
{
int saved_errno = errno;
chmod_or_fchmod (dst_name, dest_desc, mode);
errno = saved_errno;
return -1;
}
/* No need to call chmod_or_fchmod at this point, since the mode bits
S_ISUID, S_ISGID, S_ISVTX are also stored in the ACL. */
return 0;
#else
return qset_acl (dst_name, dest_desc, mode);
#endif
}
/* 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
DST_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.
Return 0 if successful, otherwise output a diagnostic and return -1. */
int
copy_acl (const char *src_name, int source_desc, const char *dst_name,
int dest_desc, mode_t mode)
{
int ret = qcopy_acl (src_name, source_desc, dst_name, dest_desc, mode);
switch (ret)
{
case -2:
error (0, errno, "%s", quote (src_name));
return -1;
case -1:
error (0, errno, _("preserving permissions for %s"), quote (dst_name));
return -1;
default:
return 0;
}
}