1
0
mirror of https://git.savannah.gnu.org/git/emacs.git synced 2024-12-03 08:30:09 +00:00
emacs/lib/qset-acl.c
Paul Eggert 035f5aaa91 Merge from gnulib, incorporating:
2015-01-01 version-etc: new year
2015-01-01 11:06:53 -08:00

677 lines
21 KiB
C

/* qset-acl.c - set access control list equivalent to a mode
Copyright (C) 2002-2003, 2005-2015 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 and Andreas Gruenbacher, and Bruno Haible. */
#include <config.h>
#define ACL_INTERNAL_INLINE _GL_EXTERN_INLINE
#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 fchmod. On systems
that don't have fchmod and if DESC is invalid, use chmod on
NAME instead.
Return 0 if successful. Return -1 and set errno upon failure. */
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);
}
/* 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.
Return 0 if successful. Return -1 and set errno upon failure. */
int
qset_acl (char const *name, int desc, mode_t mode)
{
#if USE_ACL
# if HAVE_ACL_GET_FILE
/* POSIX 1003.1e draft 17 (abandoned) specific version. */
/* Linux, FreeBSD, Mac OS X, IRIX, Tru64 */
# if !HAVE_ACL_TYPE_EXTENDED
/* Linux, FreeBSD, IRIX, Tru64 */
/* We must also 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) /* Linux */
{
acl = acl_from_mode (mode);
if (!acl)
return -1;
}
else /* FreeBSD, IRIX, Tru64 */
{
/* If we were to create the ACL using the functions acl_init(),
acl_create_entry(), acl_set_tag_type(), acl_set_qualifier(),
acl_get_permset(), acl_clear_perm[s](), acl_add_perm(), we
would need to create a qualifier. I don't know how to do this.
So create it using acl_from_text(). */
# if HAVE_ACL_FREE_TEXT /* Tru64 */
char acl_text[] = "u::---,g::---,o::---,";
# else /* FreeBSD, IRIX */
char acl_text[] = "u::---,g::---,o::---";
# endif
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)
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_errno_valid (errno))
return chmod_or_fchmod (name, desc, mode);
errno = saved_errno;
return -1;
}
else
acl_free (acl);
if (S_ISDIR (mode) && acl_delete_def_file (name))
return -1;
if (!MODE_INSIDE_ACL || (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 (name, desc, mode);
}
return 0;
# else /* HAVE_ACL_TYPE_EXTENDED */
/* Mac OS X */
/* On Mac OS 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;
/* Remove the ACL if the file has ACLs. */
if (HAVE_ACL_GET_FD && desc != -1)
acl = acl_get_fd (desc);
else
acl = acl_get_file (name, ACL_TYPE_EXTENDED);
if (acl)
{
acl_free (acl);
acl = acl_init (0);
if (acl)
{
if (HAVE_ACL_SET_FD && desc != -1)
ret = acl_set_fd (desc, acl);
else
ret = acl_set_file (name, ACL_TYPE_EXTENDED, acl);
if (ret != 0)
{
int saved_errno = errno;
acl_free (acl);
if (! acl_errno_valid (saved_errno))
return chmod_or_fchmod (name, desc, mode);
errno = saved_errno;
return -1;
}
acl_free (acl);
}
}
/* Since !MODE_INSIDE_ACL, we have to call chmod explicitly. */
return chmod_or_fchmod (name, desc, mode);
# endif
# elif HAVE_FACL && defined GETACL /* Solaris, Cygwin, not HP-UX */
int done_setacl = 0;
# 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). */
/* The flags in the ace_t structure changed in a binary incompatible way
when ACL_NO_TRIVIAL etc. were introduced in <sys/acl.h> version 1.15.
How to distinguish the two conventions at runtime?
We fetch the existing ACL. In the old convention, usually three ACEs have
a_flags = ACE_OWNER / ACE_GROUP / ACE_OTHER, in the range 0x0100..0x0400.
In the new convention, these values are not used. */
int convention;
{
/* Initially, try to read the entries into a stack-allocated buffer.
Use malloc if it does not fit. */
enum
{
alloc_init = 4000 / sizeof (ace_t), /* >= 3 */
alloc_max = MIN (INT_MAX, SIZE_MAX / sizeof (ace_t))
};
ace_t buf[alloc_init];
size_t alloc = alloc_init;
ace_t *entries = buf;
ace_t *malloced = NULL;
int count;
for (;;)
{
count = (desc != -1
? facl (desc, ACE_GETACL, alloc, entries)
: acl (name, ACE_GETACL, alloc, entries));
if (count < 0 && errno == ENOSPC)
{
/* Increase the size of the buffer. */
free (malloced);
if (alloc > alloc_max / 2)
{
errno = ENOMEM;
return -1;
}
alloc = 2 * alloc; /* <= alloc_max */
entries = malloced = (ace_t *) malloc (alloc * sizeof (ace_t));
if (entries == NULL)
{
errno = ENOMEM;
return -1;
}
continue;
}
break;
}
if (count <= 0)
convention = -1;
else
{
int i;
convention = 0;
for (i = 0; i < count; i++)
if (entries[i].a_flags & (OLD_ACE_OWNER | OLD_ACE_GROUP | OLD_ACE_OTHER))
{
convention = 1;
break;
}
}
free (malloced);
}
if (convention >= 0)
{
ace_t entries[6];
int count;
int ret;
if (convention)
{
/* Running on Solaris 10. */
entries[0].a_type = OLD_ALLOW;
entries[0].a_flags = OLD_ACE_OWNER;
entries[0].a_who = 0; /* irrelevant */
entries[0].a_access_mask = (mode >> 6) & 7;
entries[1].a_type = OLD_ALLOW;
entries[1].a_flags = OLD_ACE_GROUP;
entries[1].a_who = 0; /* irrelevant */
entries[1].a_access_mask = (mode >> 3) & 7;
entries[2].a_type = OLD_ALLOW;
entries[2].a_flags = OLD_ACE_OTHER;
entries[2].a_who = 0;
entries[2].a_access_mask = mode & 7;
count = 3;
}
else
{
/* Running on Solaris 10 (newer version) or Solaris 11.
The details here were found through "/bin/ls -lvd somefiles". */
entries[0].a_type = NEW_ACE_ACCESS_DENIED_ACE_TYPE;
entries[0].a_flags = NEW_ACE_OWNER;
entries[0].a_who = 0; /* irrelevant */
entries[0].a_access_mask = 0;
entries[1].a_type = NEW_ACE_ACCESS_ALLOWED_ACE_TYPE;
entries[1].a_flags = NEW_ACE_OWNER;
entries[1].a_who = 0; /* irrelevant */
entries[1].a_access_mask = NEW_ACE_WRITE_NAMED_ATTRS
| NEW_ACE_WRITE_ATTRIBUTES
| NEW_ACE_WRITE_ACL
| NEW_ACE_WRITE_OWNER;
if (mode & 0400)
entries[1].a_access_mask |= NEW_ACE_READ_DATA;
else
entries[0].a_access_mask |= NEW_ACE_READ_DATA;
if (mode & 0200)
entries[1].a_access_mask |= NEW_ACE_WRITE_DATA | NEW_ACE_APPEND_DATA;
else
entries[0].a_access_mask |= NEW_ACE_WRITE_DATA | NEW_ACE_APPEND_DATA;
if (mode & 0100)
entries[1].a_access_mask |= NEW_ACE_EXECUTE;
else
entries[0].a_access_mask |= NEW_ACE_EXECUTE;
entries[2].a_type = NEW_ACE_ACCESS_DENIED_ACE_TYPE;
entries[2].a_flags = NEW_ACE_GROUP | NEW_ACE_IDENTIFIER_GROUP;
entries[2].a_who = 0; /* irrelevant */
entries[2].a_access_mask = 0;
entries[3].a_type = NEW_ACE_ACCESS_ALLOWED_ACE_TYPE;
entries[3].a_flags = NEW_ACE_GROUP | NEW_ACE_IDENTIFIER_GROUP;
entries[3].a_who = 0; /* irrelevant */
entries[3].a_access_mask = 0;
if (mode & 0040)
entries[3].a_access_mask |= NEW_ACE_READ_DATA;
else
entries[2].a_access_mask |= NEW_ACE_READ_DATA;
if (mode & 0020)
entries[3].a_access_mask |= NEW_ACE_WRITE_DATA | NEW_ACE_APPEND_DATA;
else
entries[2].a_access_mask |= NEW_ACE_WRITE_DATA | NEW_ACE_APPEND_DATA;
if (mode & 0010)
entries[3].a_access_mask |= NEW_ACE_EXECUTE;
else
entries[2].a_access_mask |= NEW_ACE_EXECUTE;
entries[4].a_type = NEW_ACE_ACCESS_DENIED_ACE_TYPE;
entries[4].a_flags = NEW_ACE_EVERYONE;
entries[4].a_who = 0;
entries[4].a_access_mask = NEW_ACE_WRITE_NAMED_ATTRS
| NEW_ACE_WRITE_ATTRIBUTES
| NEW_ACE_WRITE_ACL
| NEW_ACE_WRITE_OWNER;
entries[5].a_type = NEW_ACE_ACCESS_ALLOWED_ACE_TYPE;
entries[5].a_flags = NEW_ACE_EVERYONE;
entries[5].a_who = 0;
entries[5].a_access_mask = NEW_ACE_READ_NAMED_ATTRS
| NEW_ACE_READ_ATTRIBUTES
| NEW_ACE_READ_ACL
| NEW_ACE_SYNCHRONIZE;
if (mode & 0004)
entries[5].a_access_mask |= NEW_ACE_READ_DATA;
else
entries[4].a_access_mask |= NEW_ACE_READ_DATA;
if (mode & 0002)
entries[5].a_access_mask |= NEW_ACE_WRITE_DATA | NEW_ACE_APPEND_DATA;
else
entries[4].a_access_mask |= NEW_ACE_WRITE_DATA | NEW_ACE_APPEND_DATA;
if (mode & 0001)
entries[5].a_access_mask |= NEW_ACE_EXECUTE;
else
entries[4].a_access_mask |= NEW_ACE_EXECUTE;
count = 6;
}
if (desc != -1)
ret = facl (desc, ACE_SETACL, count, entries);
else
ret = acl (name, ACE_SETACL, count, entries);
if (ret < 0 && errno != EINVAL && errno != ENOTSUP)
{
if (errno == ENOSYS)
return chmod_or_fchmod (name, desc, mode);
return -1;
}
if (ret == 0)
done_setacl = 1;
}
# endif
if (!done_setacl)
{
aclent_t entries[3];
int ret;
entries[0].a_type = USER_OBJ;
entries[0].a_id = 0; /* irrelevant */
entries[0].a_perm = (mode >> 6) & 7;
entries[1].a_type = GROUP_OBJ;
entries[1].a_id = 0; /* irrelevant */
entries[1].a_perm = (mode >> 3) & 7;
entries[2].a_type = OTHER_OBJ;
entries[2].a_id = 0;
entries[2].a_perm = mode & 7;
if (desc != -1)
ret = facl (desc, SETACL,
sizeof (entries) / sizeof (aclent_t), entries);
else
ret = acl (name, SETACL,
sizeof (entries) / sizeof (aclent_t), entries);
if (ret < 0)
{
if (errno == ENOSYS || errno == EOPNOTSUPP)
return chmod_or_fchmod (name, desc, mode);
return -1;
}
}
if (!MODE_INSIDE_ACL || (mode & (S_ISUID | S_ISGID | S_ISVTX)))
{
/* We did not call chmod so far, so the special bits have not yet
been set. */
return chmod_or_fchmod (name, desc, mode);
}
return 0;
# elif HAVE_GETACL /* HP-UX */
struct stat statbuf;
int ret;
if (desc != -1)
ret = fstat (desc, &statbuf);
else
ret = stat (name, &statbuf);
if (ret < 0)
return -1;
{
struct acl_entry entries[3];
entries[0].uid = statbuf.st_uid;
entries[0].gid = ACL_NSGROUP;
entries[0].mode = (mode >> 6) & 7;
entries[1].uid = ACL_NSUSER;
entries[1].gid = statbuf.st_gid;
entries[1].mode = (mode >> 3) & 7;
entries[2].uid = ACL_NSUSER;
entries[2].gid = ACL_NSGROUP;
entries[2].mode = mode & 7;
if (desc != -1)
ret = fsetacl (desc, sizeof (entries) / sizeof (struct acl_entry), entries);
else
ret = setacl (name, sizeof (entries) / sizeof (struct acl_entry), entries);
}
if (ret < 0)
{
if (!(errno == ENOSYS || errno == EOPNOTSUPP || errno == ENOTSUP))
return -1;
# if HAVE_ACLV_H /* HP-UX >= 11.11 */
{
struct acl entries[4];
entries[0].a_type = USER_OBJ;
entries[0].a_id = 0; /* irrelevant */
entries[0].a_perm = (mode >> 6) & 7;
entries[1].a_type = GROUP_OBJ;
entries[1].a_id = 0; /* irrelevant */
entries[1].a_perm = (mode >> 3) & 7;
entries[2].a_type = CLASS_OBJ;
entries[2].a_id = 0;
entries[2].a_perm = (mode >> 3) & 7;
entries[3].a_type = OTHER_OBJ;
entries[3].a_id = 0;
entries[3].a_perm = mode & 7;
ret = aclsort (sizeof (entries) / sizeof (struct acl), 1, entries);
if (ret > 0)
abort ();
if (ret < 0)
{
if (0)
return chmod_or_fchmod (name, desc, mode);
return -1;
}
ret = acl ((char *) name, ACL_SET,
sizeof (entries) / sizeof (struct acl), entries);
if (ret < 0)
{
if (errno == ENOSYS || errno == EOPNOTSUPP || errno == EINVAL)
return chmod_or_fchmod (name, desc, mode);
return -1;
}
}
# else
return chmod_or_fchmod (name, desc, mode);
# endif
}
if (mode & (S_ISUID | S_ISGID | S_ISVTX))
{
/* We did not call chmod so far, so the special bits have not yet
been set. */
return chmod_or_fchmod (name, desc, mode);
}
return 0;
# elif HAVE_ACLX_GET && defined ACL_AIX_WIP /* AIX */
acl_type_list_t types;
size_t types_size = sizeof (types);
acl_type_t type;
if (aclx_gettypes (name, &types, &types_size) < 0
|| types.num_entries == 0)
return chmod_or_fchmod (name, desc, mode);
/* XXX Do we need to clear all types of ACLs for the given file, or is it
sufficient to clear the first one? */
type = types.entries[0];
if (type.u64 == ACL_AIXC)
{
union { struct acl a; char room[128]; } u;
int ret;
u.a.acl_len = (char *) &u.a.acl_ext[0] - (char *) &u.a; /* no entries */
u.a.acl_mode = mode & ~(S_IXACL | 0777);
u.a.u_access = (mode >> 6) & 7;
u.a.g_access = (mode >> 3) & 7;
u.a.o_access = mode & 7;
if (desc != -1)
ret = aclx_fput (desc, SET_ACL | SET_MODE_S_BITS,
type, &u.a, u.a.acl_len, mode);
else
ret = aclx_put (name, SET_ACL | SET_MODE_S_BITS,
type, &u.a, u.a.acl_len, mode);
if (!(ret < 0 && errno == ENOSYS))
return ret;
}
else if (type.u64 == ACL_NFS4)
{
union { nfs4_acl_int_t a; char room[128]; } u;
nfs4_ace_int_t *ace;
int ret;
u.a.aclVersion = NFS4_ACL_INT_STRUCT_VERSION;
u.a.aclEntryN = 0;
ace = &u.a.aclEntry[0];
{
ace->flags = ACE4_ID_SPECIAL;
ace->aceWho.special_whoid = ACE4_WHO_OWNER;
ace->aceType = ACE4_ACCESS_ALLOWED_ACE_TYPE;
ace->aceFlags = 0;
ace->aceMask =
(mode & 0400 ? ACE4_READ_DATA | ACE4_LIST_DIRECTORY : 0)
| (mode & 0200
? ACE4_WRITE_DATA | ACE4_ADD_FILE | ACE4_APPEND_DATA
| ACE4_ADD_SUBDIRECTORY
: 0)
| (mode & 0100 ? ACE4_EXECUTE : 0);
ace->aceWhoString[0] = '\0';
ace->entryLen = (char *) &ace->aceWhoString[4] - (char *) ace;
ace = (nfs4_ace_int_t *) (char *) &ace->aceWhoString[4];
u.a.aclEntryN++;
}
{
ace->flags = ACE4_ID_SPECIAL;
ace->aceWho.special_whoid = ACE4_WHO_GROUP;
ace->aceType = ACE4_ACCESS_ALLOWED_ACE_TYPE;
ace->aceFlags = 0;
ace->aceMask =
(mode & 0040 ? ACE4_READ_DATA | ACE4_LIST_DIRECTORY : 0)
| (mode & 0020
? ACE4_WRITE_DATA | ACE4_ADD_FILE | ACE4_APPEND_DATA
| ACE4_ADD_SUBDIRECTORY
: 0)
| (mode & 0010 ? ACE4_EXECUTE : 0);
ace->aceWhoString[0] = '\0';
ace->entryLen = (char *) &ace->aceWhoString[4] - (char *) ace;
ace = (nfs4_ace_int_t *) (char *) &ace->aceWhoString[4];
u.a.aclEntryN++;
}
{
ace->flags = ACE4_ID_SPECIAL;
ace->aceWho.special_whoid = ACE4_WHO_EVERYONE;
ace->aceType = ACE4_ACCESS_ALLOWED_ACE_TYPE;
ace->aceFlags = 0;
ace->aceMask =
(mode & 0004 ? ACE4_READ_DATA | ACE4_LIST_DIRECTORY : 0)
| (mode & 0002
? ACE4_WRITE_DATA | ACE4_ADD_FILE | ACE4_APPEND_DATA
| ACE4_ADD_SUBDIRECTORY
: 0)
| (mode & 0001 ? ACE4_EXECUTE : 0);
ace->aceWhoString[0] = '\0';
ace->entryLen = (char *) &ace->aceWhoString[4] - (char *) ace;
ace = (nfs4_ace_int_t *) (char *) &ace->aceWhoString[4];
u.a.aclEntryN++;
}
u.a.aclLength = (char *) ace - (char *) &u.a;
if (desc != -1)
ret = aclx_fput (desc, SET_ACL | SET_MODE_S_BITS,
type, &u.a, u.a.aclLength, mode);
else
ret = aclx_put (name, SET_ACL | SET_MODE_S_BITS,
type, &u.a, u.a.aclLength, mode);
if (!(ret < 0 && errno == ENOSYS))
return ret;
}
return chmod_or_fchmod (name, desc, mode);
# elif HAVE_STATACL /* older AIX */
union { struct acl a; char room[128]; } u;
int ret;
u.a.acl_len = (char *) &u.a.acl_ext[0] - (char *) &u.a; /* no entries */
u.a.acl_mode = mode & ~(S_IXACL | 0777);
u.a.u_access = (mode >> 6) & 7;
u.a.g_access = (mode >> 3) & 7;
u.a.o_access = mode & 7;
if (desc != -1)
ret = fchacl (desc, &u.a, u.a.acl_len);
else
ret = chacl (name, &u.a, u.a.acl_len);
if (ret < 0 && errno == ENOSYS)
return chmod_or_fchmod (name, desc, mode);
return ret;
# elif HAVE_ACLSORT /* NonStop Kernel */
struct acl entries[4];
int ret;
entries[0].a_type = USER_OBJ;
entries[0].a_id = 0; /* irrelevant */
entries[0].a_perm = (mode >> 6) & 7;
entries[1].a_type = GROUP_OBJ;
entries[1].a_id = 0; /* irrelevant */
entries[1].a_perm = (mode >> 3) & 7;
entries[2].a_type = CLASS_OBJ;
entries[2].a_id = 0;
entries[2].a_perm = (mode >> 3) & 7;
entries[3].a_type = OTHER_OBJ;
entries[3].a_id = 0;
entries[3].a_perm = mode & 7;
ret = aclsort (sizeof (entries) / sizeof (struct acl), 1, entries);
if (ret > 0)
abort ();
if (ret < 0)
{
if (0)
return chmod_or_fchmod (name, desc, mode);
return -1;
}
ret = acl ((char *) name, ACL_SET,
sizeof (entries) / sizeof (struct acl), entries);
if (ret < 0)
{
if (0)
return chmod_or_fchmod (name, desc, mode);
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. */
return chmod_or_fchmod (name, desc, mode);
}
return 0;
# else /* Unknown flavor of ACLs */
return chmod_or_fchmod (name, desc, mode);
# endif
#else /* !USE_ACL */
return chmod_or_fchmod (name, desc, mode);
#endif
}