497 lines
12 KiB
C++
497 lines
12 KiB
C++
/* ntea.cc: code for manipulating Extended Attributes
|
|
|
|
Copyright 1997, 1998, 2000, 2001, 2006, 2008 Red Hat, Inc.
|
|
|
|
This file is part of Cygwin.
|
|
|
|
This software is a copyrighted work licensed under the terms of the
|
|
Cygwin license. Please consult the file "CYGWIN_LICENSE" for
|
|
details. */
|
|
|
|
#include "winsup.h"
|
|
#include "cygtls.h"
|
|
#include "security.h"
|
|
#include "path.h"
|
|
#include "fhandler.h"
|
|
#include "dtable.h"
|
|
#include "cygheap.h"
|
|
#include "ntdll.h"
|
|
#include <stdlib.h>
|
|
#include <attr/xattr.h>
|
|
|
|
#define MAX_EA_NAME_LEN 256
|
|
#define MAX_EA_VALUE_LEN 65536
|
|
|
|
/* At least one maximum sized entry fits. */
|
|
#define EA_BUFSIZ (sizeof (FILE_FULL_EA_INFORMATION) + MAX_EA_NAME_LEN \
|
|
+ MAX_EA_VALUE_LEN)
|
|
|
|
#define NEXT_FEA(p) ((PFILE_FULL_EA_INFORMATION) (p->NextEntryOffset \
|
|
? (char *) p + p->NextEntryOffset : NULL))
|
|
|
|
ssize_t __stdcall
|
|
read_ea (HANDLE hdl, path_conv &pc, const char *name, char *value, size_t size)
|
|
{
|
|
OBJECT_ATTRIBUTES attr;
|
|
NTSTATUS status;
|
|
IO_STATUS_BLOCK io;
|
|
ssize_t ret = -1;
|
|
HANDLE h = hdl;
|
|
ULONG glen = 0;
|
|
PFILE_GET_EA_INFORMATION gea = NULL;
|
|
PFILE_FULL_EA_INFORMATION fea;
|
|
/* We have to store the latest EaName to compare with the next one, since
|
|
ZwQueryEaFile has a bug when accessing files on a remote share. It
|
|
returns the last EA entry of the file infinitely. Even utilizing the
|
|
optional EaIndex only helps marginally. If you use that, the last
|
|
EA in the file is returned twice. */
|
|
char lastname[MAX_EA_NAME_LEN];
|
|
|
|
myfault efault;
|
|
if (efault.faulted (EFAULT))
|
|
goto out;
|
|
|
|
pc.get_object_attr (attr, sec_none_nih);
|
|
|
|
debug_printf ("read_ea (%S, %s, %p, %lu)",
|
|
attr.ObjectName, name, value, size);
|
|
|
|
fea = (PFILE_FULL_EA_INFORMATION) alloca (EA_BUFSIZ);
|
|
|
|
if (name)
|
|
{
|
|
size_t nlen;
|
|
|
|
/* Samba hides the user namespace from Windows clients. If we try to
|
|
retrieve a user namespace item, we remove the leading namespace from
|
|
the name, otherwise the search fails. */
|
|
if (!pc.fs_is_samba ())
|
|
/* nothing to do */;
|
|
else if (ascii_strncasematch (name, "user.", 5))
|
|
name += 5;
|
|
else
|
|
{
|
|
set_errno (ENOATTR);
|
|
goto out;
|
|
}
|
|
|
|
if ((nlen = strlen (name)) >= MAX_EA_NAME_LEN)
|
|
{
|
|
set_errno (EINVAL);
|
|
return -1;
|
|
}
|
|
glen = sizeof (FILE_GET_EA_INFORMATION) + nlen;
|
|
gea = (PFILE_GET_EA_INFORMATION) alloca (glen);
|
|
|
|
gea->NextEntryOffset = 0;
|
|
gea->EaNameLength = nlen;
|
|
strcpy (gea->EaName, name);
|
|
}
|
|
|
|
while (true)
|
|
{
|
|
if (h)
|
|
{
|
|
status = NtQueryEaFile (h, &io, fea, EA_BUFSIZ, TRUE, gea, glen,
|
|
NULL, TRUE);
|
|
if (status != STATUS_ACCESS_DENIED || !hdl)
|
|
break;
|
|
}
|
|
status = NtOpenFile (&h, READ_CONTROL | FILE_READ_EA, &attr, &io,
|
|
FILE_SHARE_VALID_FLAGS, FILE_OPEN_FOR_BACKUP_INTENT);
|
|
if (!NT_SUCCESS (status))
|
|
break;
|
|
hdl = NULL;
|
|
}
|
|
if (!NT_SUCCESS (status))
|
|
{
|
|
if (status == STATUS_NO_EAS_ON_FILE)
|
|
ret = 0;
|
|
else if (status == STATUS_NONEXISTENT_EA_ENTRY)
|
|
/* Actually this error code is either never generated, or it was only
|
|
generated in some old and long forgotton NT version. See below. */
|
|
set_errno (ENOATTR);
|
|
else
|
|
__seterrno_from_nt_status (status);
|
|
goto out;
|
|
}
|
|
if (name)
|
|
{
|
|
if (size > 0)
|
|
{
|
|
if (size < fea->EaValueLength)
|
|
{
|
|
set_errno (ERANGE);
|
|
goto out;
|
|
}
|
|
/* Another weird behaviour of ZwQueryEaFile. If you ask for a
|
|
specific EA which is not present in the file's EA list, you don't
|
|
get a useful error code like STATUS_NONEXISTENT_EA_ENTRY. Rather
|
|
ZwQueryEaFile returns success with the entry's EaValueLength
|
|
set to 0. */
|
|
if (!fea->EaValueLength)
|
|
{
|
|
set_errno (ENOATTR);
|
|
goto out;
|
|
}
|
|
else
|
|
memcpy (value, fea->EaName + fea->EaNameLength + 1,
|
|
fea->EaValueLength);
|
|
}
|
|
ret = fea->EaValueLength;
|
|
}
|
|
else
|
|
{
|
|
ret = 0;
|
|
do
|
|
{
|
|
if (pc.fs_is_samba ()) /* See below. */
|
|
fea->EaNameLength += 5;
|
|
if (size > 0)
|
|
{
|
|
if ((size_t) ret + fea->EaNameLength + 1 > size)
|
|
{
|
|
set_errno (ERANGE);
|
|
goto out;
|
|
}
|
|
/* Samba hides the user namespace from Windows clients. We add
|
|
it in EA listings to keep tools like attr/getfattr/setfattr
|
|
happy. */
|
|
char tmpbuf[MAX_EA_NAME_LEN * 2], *tp = tmpbuf;
|
|
if (pc.fs_is_samba ())
|
|
tp = stpcpy (tmpbuf, "user.");
|
|
stpcpy (tp, fea->EaName);
|
|
/* NTFS stores all EA names in uppercase unfortunately. To keep
|
|
compatibility with ext/xfs EA namespaces and accompanying
|
|
tools, which expect the namespaces to be lower case, we return
|
|
EA names in lowercase if the file is on a native NTFS. */
|
|
if (pc.fs_is_ntfs ())
|
|
strlwr (tp);
|
|
tp = stpcpy (value, tmpbuf) + 1;
|
|
ret += tp - value;
|
|
value = tp;
|
|
}
|
|
else
|
|
ret += fea->EaNameLength + 1;
|
|
strcpy (lastname, fea->EaName);
|
|
status = NtQueryEaFile (h, &io, fea, EA_BUFSIZ, TRUE, NULL, 0,
|
|
NULL, FALSE);
|
|
}
|
|
while (NT_SUCCESS (status) && strcmp (lastname, fea->EaName) != 0);
|
|
}
|
|
|
|
out:
|
|
if (!hdl)
|
|
CloseHandle (h);
|
|
debug_printf ("%d = read_ea (%S, %s, %p, %lu)",
|
|
ret, attr.ObjectName, name, value, size);
|
|
return ret;
|
|
}
|
|
|
|
int __stdcall
|
|
write_ea (HANDLE hdl, path_conv &pc, const char *name, const char *value,
|
|
size_t size, int flags)
|
|
{
|
|
OBJECT_ATTRIBUTES attr;
|
|
NTSTATUS status;
|
|
IO_STATUS_BLOCK io;
|
|
int ret = -1;
|
|
HANDLE h = hdl;
|
|
PFILE_FULL_EA_INFORMATION fea;
|
|
ULONG flen;
|
|
size_t nlen;
|
|
|
|
myfault efault;
|
|
if (efault.faulted (EFAULT))
|
|
goto out;
|
|
|
|
pc.get_object_attr (attr, sec_none_nih);
|
|
|
|
debug_printf ("write_ea (%S, %s, %p, %lu, %d)",
|
|
attr.ObjectName, name, value, size, flags);
|
|
|
|
/* Samba hides the user namespace from Windows clients. If we get a
|
|
user namespace item, we remove the leading namespace from the name.
|
|
This keeps tools like attr/getfattr/setfattr happy. Otherwise
|
|
setting the EA fails as if we don't have the permissions. */
|
|
/* Samba hides the user namespace from Windows clients. If we try to
|
|
retrieve a user namespace item, we remove the leading namespace from
|
|
the name, otherwise the search fails. */
|
|
if (!pc.fs_is_samba ())
|
|
/* nothing to do */;
|
|
else if (ascii_strncasematch (name, "user.", 5))
|
|
name += 5;
|
|
else
|
|
{
|
|
set_errno (ENOATTR);
|
|
goto out;
|
|
}
|
|
|
|
/* removexattr is supposed to fail with ENOATTR if the requested EA is not
|
|
available. This is equivalent to the XATTR_REPLACE flag for setxattr. */
|
|
if (!value)
|
|
flags = XATTR_REPLACE;
|
|
|
|
if (flags)
|
|
{
|
|
if (flags != XATTR_CREATE && flags != XATTR_REPLACE)
|
|
{
|
|
set_errno (EINVAL);
|
|
goto out;
|
|
}
|
|
ssize_t rret = read_ea (hdl, pc, name, NULL, 0);
|
|
if (flags == XATTR_CREATE && rret > 0)
|
|
{
|
|
set_errno (EEXIST);
|
|
goto out;
|
|
}
|
|
if (flags == XATTR_REPLACE && rret < 0)
|
|
goto out;
|
|
}
|
|
|
|
if ((nlen = strlen (name)) >= MAX_EA_NAME_LEN)
|
|
{
|
|
set_errno (EINVAL);
|
|
goto out;
|
|
}
|
|
flen = sizeof (FILE_FULL_EA_INFORMATION) + nlen + 1 + size;
|
|
fea = (PFILE_FULL_EA_INFORMATION) alloca (flen);
|
|
fea->NextEntryOffset = 0;
|
|
fea->Flags = 0;
|
|
fea->EaNameLength = nlen;
|
|
fea->EaValueLength = size;
|
|
strcpy (fea->EaName, name);
|
|
if (value)
|
|
memcpy (fea->EaName + fea->EaNameLength + 1, value, size);
|
|
|
|
while (true)
|
|
{
|
|
if (h)
|
|
{
|
|
status = NtSetEaFile (h, &io, fea, flen);
|
|
if (status != STATUS_ACCESS_DENIED || !hdl)
|
|
break;
|
|
}
|
|
status = NtOpenFile (&h, READ_CONTROL | FILE_WRITE_EA, &attr, &io,
|
|
FILE_SHARE_VALID_FLAGS, FILE_OPEN_FOR_BACKUP_INTENT);
|
|
if (!NT_SUCCESS (status))
|
|
break;
|
|
hdl = NULL;
|
|
}
|
|
if (!NT_SUCCESS (status))
|
|
{
|
|
/* STATUS_EA_TOO_LARGE has a matching Win32 error ERROR_EA_TABLE_FULL.
|
|
Too bad RtlNtStatusToDosError does not translate STATUS_EA_TOO_LARGE
|
|
to ERROR_EA_TABLE_FULL, but to ERROR_EA_LIST_INCONSISTENT. This
|
|
error code is also returned for STATUS_EA_LIST_INCONSISTENT, which
|
|
means the incoming EA list is... inconsistent. For obvious reasons
|
|
we translate ERROR_EA_LIST_INCONSISTENT to EINVAL, so we have to
|
|
handle STATUS_EA_TOO_LARGE explicitely here, to get the correct
|
|
mapping to ENOSPC. */
|
|
if (status == STATUS_EA_TOO_LARGE)
|
|
set_errno (ENOSPC);
|
|
else
|
|
__seterrno_from_nt_status (status);
|
|
}
|
|
else
|
|
ret = 0;
|
|
|
|
out:
|
|
if (!hdl)
|
|
CloseHandle (h);
|
|
debug_printf ("%d = write_ea (%S, %s, %p, %lu, %d)",
|
|
ret, attr.ObjectName, name, value, size, flags);
|
|
return ret;
|
|
}
|
|
|
|
static ssize_t __stdcall
|
|
getxattr_worker (path_conv &pc, const char *name, void *value, size_t size)
|
|
{
|
|
int res = -1;
|
|
|
|
if (pc.error)
|
|
{
|
|
debug_printf ("got %d error from build_fh_name", pc.error);
|
|
set_errno (pc.error);
|
|
}
|
|
else if (pc.exists ())
|
|
{
|
|
fhandler_base *fh;
|
|
|
|
if (!(fh = build_fh_pc (pc)))
|
|
return -1;
|
|
|
|
res = fh->fgetxattr (name, value, size);
|
|
delete fh;
|
|
}
|
|
else
|
|
set_errno (ENOENT);
|
|
return res;
|
|
}
|
|
|
|
extern "C" ssize_t
|
|
getxattr (const char *path, const char *name, void *value, size_t size)
|
|
{
|
|
if (!name)
|
|
{
|
|
set_errno (EINVAL);
|
|
return -1;
|
|
}
|
|
path_conv pc (path, PC_SYM_FOLLOW | PC_POSIX, stat_suffixes);
|
|
return getxattr_worker (pc, name, value, size);
|
|
}
|
|
|
|
extern "C" ssize_t
|
|
lgetxattr (const char *path, const char *name, void *value, size_t size)
|
|
{
|
|
if (!name)
|
|
{
|
|
set_errno (EINVAL);
|
|
return -1;
|
|
}
|
|
path_conv pc (path, PC_SYM_NOFOLLOW | PC_POSIX, stat_suffixes);
|
|
return getxattr_worker (pc, name, value, size);
|
|
}
|
|
|
|
extern "C" ssize_t
|
|
fgetxattr (int fd, const char *name, void *value, size_t size)
|
|
{
|
|
int res;
|
|
|
|
if (!name)
|
|
{
|
|
set_errno (EINVAL);
|
|
return -1;
|
|
}
|
|
cygheap_fdget cfd (fd);
|
|
if (cfd < 0)
|
|
res = -1;
|
|
else
|
|
res = cfd->fgetxattr (name, value, size);
|
|
return res;
|
|
}
|
|
|
|
extern "C" ssize_t
|
|
listxattr (const char *path, char *list, size_t size)
|
|
{
|
|
path_conv pc (path, PC_SYM_FOLLOW | PC_POSIX, stat_suffixes);
|
|
return getxattr_worker (pc, NULL, list, size);
|
|
}
|
|
|
|
extern "C" ssize_t
|
|
llistxattr (const char *path, char *list, size_t size)
|
|
{
|
|
path_conv pc (path, PC_SYM_NOFOLLOW | PC_POSIX, stat_suffixes);
|
|
return getxattr_worker (pc, NULL, list, size);
|
|
}
|
|
|
|
extern "C" ssize_t
|
|
flistxattr (int fd, char *list, size_t size)
|
|
{
|
|
int res;
|
|
|
|
cygheap_fdget cfd (fd);
|
|
if (cfd < 0)
|
|
res = -1;
|
|
else
|
|
res = cfd->fgetxattr (NULL, list, size);
|
|
return res;
|
|
}
|
|
|
|
static int __stdcall
|
|
setxattr_worker (path_conv &pc, const char *name, const void *value,
|
|
size_t size, int flags)
|
|
{
|
|
int res = -1;
|
|
|
|
if (pc.error)
|
|
{
|
|
debug_printf ("got %d error from build_fh_name", pc.error);
|
|
set_errno (pc.error);
|
|
}
|
|
else if (pc.exists ())
|
|
{
|
|
fhandler_base *fh;
|
|
|
|
if (!(fh = build_fh_pc (pc)))
|
|
return -1;
|
|
|
|
res = fh->fsetxattr (name, value, size, flags);
|
|
delete fh;
|
|
}
|
|
else
|
|
set_errno (ENOENT);
|
|
return res;
|
|
}
|
|
|
|
extern "C" int
|
|
setxattr (const char *path, const char *name, const void *value, size_t size,
|
|
int flags)
|
|
{
|
|
if (!size)
|
|
{
|
|
set_errno (EINVAL);
|
|
return -1;
|
|
}
|
|
path_conv pc (path, PC_SYM_NOFOLLOW | PC_POSIX, stat_suffixes);
|
|
return setxattr_worker (pc, name, value, size, flags);
|
|
}
|
|
|
|
extern "C" int
|
|
lsetxattr (const char *path, const char *name, const void *value, size_t size,
|
|
int flags)
|
|
{
|
|
if (!size)
|
|
{
|
|
set_errno (EINVAL);
|
|
return -1;
|
|
}
|
|
path_conv pc (path, PC_SYM_NOFOLLOW | PC_POSIX, stat_suffixes);
|
|
return setxattr_worker (pc, name, value, size, flags);
|
|
}
|
|
|
|
extern "C" int
|
|
fsetxattr (int fd, const char *name, const void *value, size_t size, int flags)
|
|
{
|
|
int res;
|
|
|
|
if (!size)
|
|
{
|
|
set_errno (EINVAL);
|
|
return -1;
|
|
}
|
|
cygheap_fdget cfd (fd);
|
|
if (cfd < 0)
|
|
res = -1;
|
|
else
|
|
res = cfd->fsetxattr (name, value, size, flags);
|
|
return res;
|
|
}
|
|
|
|
extern "C" int
|
|
removexattr (const char *path, const char *name)
|
|
{
|
|
path_conv pc (path, PC_SYM_FOLLOW | PC_POSIX, stat_suffixes);
|
|
return setxattr_worker (pc, name, NULL, 0, 0);
|
|
}
|
|
|
|
extern "C" int
|
|
lremovexattr (const char *path, const char *name)
|
|
{
|
|
path_conv pc (path, PC_SYM_NOFOLLOW | PC_POSIX, stat_suffixes);
|
|
return setxattr_worker (pc, name, NULL, 0, 0);
|
|
}
|
|
|
|
extern "C" int
|
|
fremovexattr (int fd, const char *name)
|
|
{
|
|
int res;
|
|
|
|
cygheap_fdget cfd (fd);
|
|
if (cfd < 0)
|
|
res = -1;
|
|
else
|
|
res = cfd->fsetxattr (name, NULL, 0, 0);
|
|
return res;
|
|
}
|