+++ /dev/null
-/*
- * Copyright (c) 2001-2002,2005 Silicon Graphics, Inc.
- * All Rights Reserved.
- *
- * 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.
- *
- * This program is distributed in the hope that it would 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 the Free Software Foundation,
- * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
- */
-#include "xfs.h"
-#include "xfs_fs.h"
-#include "xfs_types.h"
-#include "xfs_bit.h"
-#include "xfs_inum.h"
-#include "xfs_ag.h"
-#include "xfs_dir2.h"
-#include "xfs_bmap_btree.h"
-#include "xfs_alloc_btree.h"
-#include "xfs_ialloc_btree.h"
-#include "xfs_dir2_sf.h"
-#include "xfs_attr_sf.h"
-#include "xfs_dinode.h"
-#include "xfs_inode.h"
-#include "xfs_btree.h"
-#include "xfs_acl.h"
-#include "xfs_attr.h"
-#include "xfs_vnodeops.h"
-
-#include <linux/capability.h>
-#include <linux/posix_acl_xattr.h>
-
-STATIC int xfs_acl_setmode(struct inode *, xfs_acl_t *, int *);
-STATIC void xfs_acl_filter_mode(mode_t, xfs_acl_t *);
-STATIC void xfs_acl_get_endian(xfs_acl_t *);
-STATIC int xfs_acl_access(uid_t, gid_t, xfs_acl_t *, mode_t, cred_t *);
-STATIC int xfs_acl_invalid(xfs_acl_t *);
-STATIC void xfs_acl_sync_mode(mode_t, xfs_acl_t *);
-STATIC void xfs_acl_get_attr(struct inode *, xfs_acl_t *, int, int, int *);
-STATIC void xfs_acl_set_attr(struct inode *, xfs_acl_t *, int, int *);
-STATIC int xfs_acl_allow_set(struct inode *, int);
-
-kmem_zone_t *xfs_acl_zone;
-
-
-/*
- * Test for existence of access ACL attribute as efficiently as possible.
- */
-int
-xfs_acl_vhasacl_access(
- struct inode *vp)
-{
- int error;
-
- xfs_acl_get_attr(vp, NULL, _ACL_TYPE_ACCESS, ATTR_KERNOVAL, &error);
- return (error == 0);
-}
-
-/*
- * Test for existence of default ACL attribute as efficiently as possible.
- */
-int
-xfs_acl_vhasacl_default(
- struct inode *vp)
-{
- int error;
-
- if (!S_ISDIR(vp->i_mode))
- return 0;
- xfs_acl_get_attr(vp, NULL, _ACL_TYPE_DEFAULT, ATTR_KERNOVAL, &error);
- return (error == 0);
-}
-
-/*
- * Convert from extended attribute representation to in-memory for XFS.
- */
-STATIC int
-posix_acl_xattr_to_xfs(
- posix_acl_xattr_header *src,
- size_t size,
- xfs_acl_t *dest)
-{
- posix_acl_xattr_entry *src_entry;
- xfs_acl_entry_t *dest_entry;
- int n;
-
- if (!src || !dest)
- return EINVAL;
-
- if (size < sizeof(posix_acl_xattr_header))
- return EINVAL;
-
- if (src->a_version != cpu_to_le32(POSIX_ACL_XATTR_VERSION))
- return EOPNOTSUPP;
-
- memset(dest, 0, sizeof(xfs_acl_t));
- dest->acl_cnt = posix_acl_xattr_count(size);
- if (dest->acl_cnt < 0 || dest->acl_cnt > XFS_ACL_MAX_ENTRIES)
- return EINVAL;
-
- /*
- * acl_set_file(3) may request that we set default ACLs with
- * zero length -- defend (gracefully) against that here.
- */
- if (!dest->acl_cnt)
- return 0;
-
- src_entry = (posix_acl_xattr_entry *)((char *)src + sizeof(*src));
- dest_entry = &dest->acl_entry[0];
-
- for (n = 0; n < dest->acl_cnt; n++, src_entry++, dest_entry++) {
- dest_entry->ae_perm = le16_to_cpu(src_entry->e_perm);
- if (_ACL_PERM_INVALID(dest_entry->ae_perm))
- return EINVAL;
- dest_entry->ae_tag = le16_to_cpu(src_entry->e_tag);
- switch(dest_entry->ae_tag) {
- case ACL_USER:
- case ACL_GROUP:
- dest_entry->ae_id = le32_to_cpu(src_entry->e_id);
- break;
- case ACL_USER_OBJ:
- case ACL_GROUP_OBJ:
- case ACL_MASK:
- case ACL_OTHER:
- dest_entry->ae_id = ACL_UNDEFINED_ID;
- break;
- default:
- return EINVAL;
- }
- }
- if (xfs_acl_invalid(dest))
- return EINVAL;
-
- return 0;
-}
-
-/*
- * Comparison function called from xfs_sort().
- * Primary key is ae_tag, secondary key is ae_id.
- */
-STATIC int
-xfs_acl_entry_compare(
- const void *va,
- const void *vb)
-{
- xfs_acl_entry_t *a = (xfs_acl_entry_t *)va,
- *b = (xfs_acl_entry_t *)vb;
-
- if (a->ae_tag == b->ae_tag)
- return (a->ae_id - b->ae_id);
- return (a->ae_tag - b->ae_tag);
-}
-
-/*
- * Convert from in-memory XFS to extended attribute representation.
- */
-STATIC int
-posix_acl_xfs_to_xattr(
- xfs_acl_t *src,
- posix_acl_xattr_header *dest,
- size_t size)
-{
- int n;
- size_t new_size = posix_acl_xattr_size(src->acl_cnt);
- posix_acl_xattr_entry *dest_entry;
- xfs_acl_entry_t *src_entry;
-
- if (size < new_size)
- return -ERANGE;
-
- /* Need to sort src XFS ACL by <ae_tag,ae_id> */
- xfs_sort(src->acl_entry, src->acl_cnt, sizeof(src->acl_entry[0]),
- xfs_acl_entry_compare);
-
- dest->a_version = cpu_to_le32(POSIX_ACL_XATTR_VERSION);
- dest_entry = &dest->a_entries[0];
- src_entry = &src->acl_entry[0];
- for (n = 0; n < src->acl_cnt; n++, dest_entry++, src_entry++) {
- dest_entry->e_perm = cpu_to_le16(src_entry->ae_perm);
- if (_ACL_PERM_INVALID(src_entry->ae_perm))
- return -EINVAL;
- dest_entry->e_tag = cpu_to_le16(src_entry->ae_tag);
- switch (src_entry->ae_tag) {
- case ACL_USER:
- case ACL_GROUP:
- dest_entry->e_id = cpu_to_le32(src_entry->ae_id);
- break;
- case ACL_USER_OBJ:
- case ACL_GROUP_OBJ:
- case ACL_MASK:
- case ACL_OTHER:
- dest_entry->e_id = cpu_to_le32(ACL_UNDEFINED_ID);
- break;
- default:
- return -EINVAL;
- }
- }
- return new_size;
-}
-
-int
-xfs_acl_vget(
- struct inode *vp,
- void *acl,
- size_t size,
- int kind)
-{
- int error;
- xfs_acl_t *xfs_acl = NULL;
- posix_acl_xattr_header *ext_acl = acl;
- int flags = 0;
-
- if(size) {
- if (!(_ACL_ALLOC(xfs_acl))) {
- error = ENOMEM;
- goto out;
- }
- memset(xfs_acl, 0, sizeof(xfs_acl_t));
- } else
- flags = ATTR_KERNOVAL;
-
- xfs_acl_get_attr(vp, xfs_acl, kind, flags, &error);
- if (error)
- goto out;
-
- if (!size) {
- error = -posix_acl_xattr_size(XFS_ACL_MAX_ENTRIES);
- } else {
- if (xfs_acl_invalid(xfs_acl)) {
- error = EINVAL;
- goto out;
- }
- if (kind == _ACL_TYPE_ACCESS)
- xfs_acl_sync_mode(XFS_I(vp)->i_d.di_mode, xfs_acl);
- error = -posix_acl_xfs_to_xattr(xfs_acl, ext_acl, size);
- }
-out:
- if(xfs_acl)
- _ACL_FREE(xfs_acl);
- return -error;
-}
-
-int
-xfs_acl_vremove(
- struct inode *vp,
- int kind)
-{
- int error;
-
- error = xfs_acl_allow_set(vp, kind);
- if (!error) {
- error = xfs_attr_remove(XFS_I(vp),
- kind == _ACL_TYPE_DEFAULT?
- SGI_ACL_DEFAULT: SGI_ACL_FILE,
- ATTR_ROOT);
- if (error == ENOATTR)
- error = 0; /* 'scool */
- }
- return -error;
-}
-
-int
-xfs_acl_vset(
- struct inode *vp,
- void *acl,
- size_t size,
- int kind)
-{
- posix_acl_xattr_header *ext_acl = acl;
- xfs_acl_t *xfs_acl;
- int error;
- int basicperms = 0; /* more than std unix perms? */
-
- if (!acl)
- return -EINVAL;
-
- if (!(_ACL_ALLOC(xfs_acl)))
- return -ENOMEM;
-
- error = posix_acl_xattr_to_xfs(ext_acl, size, xfs_acl);
- if (error) {
- _ACL_FREE(xfs_acl);
- return -error;
- }
- if (!xfs_acl->acl_cnt) {
- _ACL_FREE(xfs_acl);
- return 0;
- }
-
- error = xfs_acl_allow_set(vp, kind);
-
- /* Incoming ACL exists, set file mode based on its value */
- if (!error && kind == _ACL_TYPE_ACCESS)
- error = xfs_acl_setmode(vp, xfs_acl, &basicperms);
-
- if (error)
- goto out;
-
- /*
- * If we have more than std unix permissions, set up the actual attr.
- * Otherwise, delete any existing attr. This prevents us from
- * having actual attrs for permissions that can be stored in the
- * standard permission bits.
- */
- if (!basicperms) {
- xfs_acl_set_attr(vp, xfs_acl, kind, &error);
- } else {
- error = -xfs_acl_vremove(vp, _ACL_TYPE_ACCESS);
- }
-
-out:
- _ACL_FREE(xfs_acl);
- return -error;
-}
-
-int
-xfs_acl_iaccess(
- xfs_inode_t *ip,
- mode_t mode,
- cred_t *cr)
-{
- xfs_acl_t *acl;
- int rval;
- struct xfs_name acl_name = {SGI_ACL_FILE, SGI_ACL_FILE_SIZE};
-
- if (!(_ACL_ALLOC(acl)))
- return -1;
-
- /* If the file has no ACL return -1. */
- rval = sizeof(xfs_acl_t);
- if (xfs_attr_fetch(ip, &acl_name, (char *)acl, &rval, ATTR_ROOT)) {
- _ACL_FREE(acl);
- return -1;
- }
- xfs_acl_get_endian(acl);
-
- /* If the file has an empty ACL return -1. */
- if (acl->acl_cnt == XFS_ACL_NOT_PRESENT) {
- _ACL_FREE(acl);
- return -1;
- }
-
- /* Synchronize ACL with mode bits */
- xfs_acl_sync_mode(ip->i_d.di_mode, acl);
-
- rval = xfs_acl_access(ip->i_d.di_uid, ip->i_d.di_gid, acl, mode, cr);
- _ACL_FREE(acl);
- return rval;
-}
-
-STATIC int
-xfs_acl_allow_set(
- struct inode *vp,
- int kind)
-{
- if (vp->i_flags & (S_IMMUTABLE|S_APPEND))
- return EPERM;
- if (kind == _ACL_TYPE_DEFAULT && !S_ISDIR(vp->i_mode))
- return ENOTDIR;
- if (vp->i_sb->s_flags & MS_RDONLY)
- return EROFS;
- if (XFS_I(vp)->i_d.di_uid != current_fsuid() && !capable(CAP_FOWNER))
- return EPERM;
- return 0;
-}
-
-/*
- * Note: cr is only used here for the capability check if the ACL test fails.
- * It is not used to find out the credentials uid or groups etc, as was
- * done in IRIX. It is assumed that the uid and groups for the current
- * thread are taken from "current" instead of the cr parameter.
- */
-STATIC int
-xfs_acl_access(
- uid_t fuid,
- gid_t fgid,
- xfs_acl_t *fap,
- mode_t md,
- cred_t *cr)
-{
- xfs_acl_entry_t matched;
- int i, allows;
- int maskallows = -1; /* true, but not 1, either */
- int seen_userobj = 0;
-
- matched.ae_tag = 0; /* Invalid type */
- matched.ae_perm = 0;
-
- for (i = 0; i < fap->acl_cnt; i++) {
- /*
- * Break out if we've got a user_obj entry or
- * a user entry and the mask (and have processed USER_OBJ)
- */
- if (matched.ae_tag == ACL_USER_OBJ)
- break;
- if (matched.ae_tag == ACL_USER) {
- if (maskallows != -1 && seen_userobj)
- break;
- if (fap->acl_entry[i].ae_tag != ACL_MASK &&
- fap->acl_entry[i].ae_tag != ACL_USER_OBJ)
- continue;
- }
- /* True if this entry allows the requested access */
- allows = ((fap->acl_entry[i].ae_perm & md) == md);
-
- switch (fap->acl_entry[i].ae_tag) {
- case ACL_USER_OBJ:
- seen_userobj = 1;
- if (fuid != current_fsuid())
- continue;
- matched.ae_tag = ACL_USER_OBJ;
- matched.ae_perm = allows;
- break;
- case ACL_USER:
- if (fap->acl_entry[i].ae_id != current_fsuid())
- continue;
- matched.ae_tag = ACL_USER;
- matched.ae_perm = allows;
- break;
- case ACL_GROUP_OBJ:
- if ((matched.ae_tag == ACL_GROUP_OBJ ||
- matched.ae_tag == ACL_GROUP) && !allows)
- continue;
- if (!in_group_p(fgid))
- continue;
- matched.ae_tag = ACL_GROUP_OBJ;
- matched.ae_perm = allows;
- break;
- case ACL_GROUP:
- if ((matched.ae_tag == ACL_GROUP_OBJ ||
- matched.ae_tag == ACL_GROUP) && !allows)
- continue;
- if (!in_group_p(fap->acl_entry[i].ae_id))
- continue;
- matched.ae_tag = ACL_GROUP;
- matched.ae_perm = allows;
- break;
- case ACL_MASK:
- maskallows = allows;
- break;
- case ACL_OTHER:
- if (matched.ae_tag != 0)
- continue;
- matched.ae_tag = ACL_OTHER;
- matched.ae_perm = allows;
- break;
- }
- }
- /*
- * First possibility is that no matched entry allows access.
- * The capability to override DAC may exist, so check for it.
- */
- switch (matched.ae_tag) {
- case ACL_OTHER:
- case ACL_USER_OBJ:
- if (matched.ae_perm)
- return 0;
- break;
- case ACL_USER:
- case ACL_GROUP_OBJ:
- case ACL_GROUP:
- if (maskallows && matched.ae_perm)
- return 0;
- break;
- case 0:
- break;
- }
-
- /* EACCES tells generic_permission to check for capability overrides */
- return EACCES;
-}
-
-/*
- * ACL validity checker.
- * This acl validation routine checks each ACL entry read in makes sense.
- */
-STATIC int
-xfs_acl_invalid(
- xfs_acl_t *aclp)
-{
- xfs_acl_entry_t *entry, *e;
- int user = 0, group = 0, other = 0, mask = 0;
- int mask_required = 0;
- int i, j;
-
- if (!aclp)
- goto acl_invalid;
-
- if (aclp->acl_cnt > XFS_ACL_MAX_ENTRIES)
- goto acl_invalid;
-
- for (i = 0; i < aclp->acl_cnt; i++) {
- entry = &aclp->acl_entry[i];
- switch (entry->ae_tag) {
- case ACL_USER_OBJ:
- if (user++)
- goto acl_invalid;
- break;
- case ACL_GROUP_OBJ:
- if (group++)
- goto acl_invalid;
- break;
- case ACL_OTHER:
- if (other++)
- goto acl_invalid;
- break;
- case ACL_USER:
- case ACL_GROUP:
- for (j = i + 1; j < aclp->acl_cnt; j++) {
- e = &aclp->acl_entry[j];
- if (e->ae_id == entry->ae_id &&
- e->ae_tag == entry->ae_tag)
- goto acl_invalid;
- }
- mask_required++;
- break;
- case ACL_MASK:
- if (mask++)
- goto acl_invalid;
- break;
- default:
- goto acl_invalid;
- }
- }
- if (!user || !group || !other || (mask_required && !mask))
- goto acl_invalid;
- else
- return 0;
-acl_invalid:
- return EINVAL;
-}
-
-/*
- * Do ACL endian conversion.
- */
-STATIC void
-xfs_acl_get_endian(
- xfs_acl_t *aclp)
-{
- xfs_acl_entry_t *ace, *end;
-
- INT_SET(aclp->acl_cnt, ARCH_CONVERT, aclp->acl_cnt);
- end = &aclp->acl_entry[0]+aclp->acl_cnt;
- for (ace = &aclp->acl_entry[0]; ace < end; ace++) {
- INT_SET(ace->ae_tag, ARCH_CONVERT, ace->ae_tag);
- INT_SET(ace->ae_id, ARCH_CONVERT, ace->ae_id);
- INT_SET(ace->ae_perm, ARCH_CONVERT, ace->ae_perm);
- }
-}
-
-/*
- * Get the ACL from the EA and do endian conversion.
- */
-STATIC void
-xfs_acl_get_attr(
- struct inode *vp,
- xfs_acl_t *aclp,
- int kind,
- int flags,
- int *error)
-{
- int len = sizeof(xfs_acl_t);
-
- ASSERT((flags & ATTR_KERNOVAL) ? (aclp == NULL) : 1);
- flags |= ATTR_ROOT;
- *error = xfs_attr_get(XFS_I(vp),
- kind == _ACL_TYPE_ACCESS ?
- SGI_ACL_FILE : SGI_ACL_DEFAULT,
- (char *)aclp, &len, flags);
- if (*error || (flags & ATTR_KERNOVAL))
- return;
- xfs_acl_get_endian(aclp);
-}
-
-/*
- * Set the EA with the ACL and do endian conversion.
- */
-STATIC void
-xfs_acl_set_attr(
- struct inode *vp,
- xfs_acl_t *aclp,
- int kind,
- int *error)
-{
- xfs_acl_entry_t *ace, *newace, *end;
- xfs_acl_t *newacl;
- int len;
-
- if (!(_ACL_ALLOC(newacl))) {
- *error = ENOMEM;
- return;
- }
-
- len = sizeof(xfs_acl_t) -
- (sizeof(xfs_acl_entry_t) * (XFS_ACL_MAX_ENTRIES - aclp->acl_cnt));
- end = &aclp->acl_entry[0]+aclp->acl_cnt;
- for (ace = &aclp->acl_entry[0], newace = &newacl->acl_entry[0];
- ace < end;
- ace++, newace++) {
- INT_SET(newace->ae_tag, ARCH_CONVERT, ace->ae_tag);
- INT_SET(newace->ae_id, ARCH_CONVERT, ace->ae_id);
- INT_SET(newace->ae_perm, ARCH_CONVERT, ace->ae_perm);
- }
- INT_SET(newacl->acl_cnt, ARCH_CONVERT, aclp->acl_cnt);
- *error = xfs_attr_set(XFS_I(vp),
- kind == _ACL_TYPE_ACCESS ?
- SGI_ACL_FILE: SGI_ACL_DEFAULT,
- (char *)newacl, len, ATTR_ROOT);
- _ACL_FREE(newacl);
-}
-
-int
-xfs_acl_vtoacl(
- struct inode *vp,
- xfs_acl_t *access_acl,
- xfs_acl_t *default_acl)
-{
- int error = 0;
-
- if (access_acl) {
- /*
- * Get the Access ACL and the mode. If either cannot
- * be obtained for some reason, invalidate the access ACL.
- */
- xfs_acl_get_attr(vp, access_acl, _ACL_TYPE_ACCESS, 0, &error);
- if (error)
- access_acl->acl_cnt = XFS_ACL_NOT_PRESENT;
- else /* We have a good ACL and the file mode, synchronize. */
- xfs_acl_sync_mode(XFS_I(vp)->i_d.di_mode, access_acl);
- }
-
- if (default_acl) {
- xfs_acl_get_attr(vp, default_acl, _ACL_TYPE_DEFAULT, 0, &error);
- if (error)
- default_acl->acl_cnt = XFS_ACL_NOT_PRESENT;
- }
- return error;
-}
-
-/*
- * This function retrieves the parent directory's acl, processes it
- * and lets the child inherit the acl(s) that it should.
- */
-int
-xfs_acl_inherit(
- struct inode *vp,
- mode_t mode,
- xfs_acl_t *pdaclp)
-{
- xfs_acl_t *cacl;
- int error = 0;
- int basicperms = 0;
-
- /*
- * If the parent does not have a default ACL, or it's an
- * invalid ACL, we're done.
- */
- if (!vp)
- return 0;
- if (!pdaclp || xfs_acl_invalid(pdaclp))
- return 0;
-
- /*
- * Copy the default ACL of the containing directory to
- * the access ACL of the new file and use the mode that
- * was passed in to set up the correct initial values for
- * the u::,g::[m::], and o:: entries. This is what makes
- * umask() "work" with ACL's.
- */
-
- if (!(_ACL_ALLOC(cacl)))
- return ENOMEM;
-
- memcpy(cacl, pdaclp, sizeof(xfs_acl_t));
- xfs_acl_filter_mode(mode, cacl);
- error = xfs_acl_setmode(vp, cacl, &basicperms);
- if (error)
- goto out_error;
-
- /*
- * Set the Default and Access ACL on the file. The mode is already
- * set on the file, so we don't need to worry about that.
- *
- * If the new file is a directory, its default ACL is a copy of
- * the containing directory's default ACL.
- */
- if (S_ISDIR(vp->i_mode))
- xfs_acl_set_attr(vp, pdaclp, _ACL_TYPE_DEFAULT, &error);
- if (!error && !basicperms)
- xfs_acl_set_attr(vp, cacl, _ACL_TYPE_ACCESS, &error);
-out_error:
- _ACL_FREE(cacl);
- return error;
-}
-
-/*
- * Set up the correct mode on the file based on the supplied ACL. This
- * makes sure that the mode on the file reflects the state of the
- * u::,g::[m::], and o:: entries in the ACL. Since the mode is where
- * the ACL is going to get the permissions for these entries, we must
- * synchronize the mode whenever we set the ACL on a file.
- */
-STATIC int
-xfs_acl_setmode(
- struct inode *vp,
- xfs_acl_t *acl,
- int *basicperms)
-{
- struct iattr iattr;
- xfs_acl_entry_t *ap;
- xfs_acl_entry_t *gap = NULL;
- int i, nomask = 1;
-
- *basicperms = 1;
-
- if (acl->acl_cnt == XFS_ACL_NOT_PRESENT)
- return 0;
-
- /*
- * Copy the u::, g::, o::, and m:: bits from the ACL into the
- * mode. The m:: bits take precedence over the g:: bits.
- */
- iattr.ia_valid = ATTR_MODE;
- iattr.ia_mode = XFS_I(vp)->i_d.di_mode;
- iattr.ia_mode &= ~(S_IRWXU|S_IRWXG|S_IRWXO);
- ap = acl->acl_entry;
- for (i = 0; i < acl->acl_cnt; ++i) {
- switch (ap->ae_tag) {
- case ACL_USER_OBJ:
- iattr.ia_mode |= ap->ae_perm << 6;
- break;
- case ACL_GROUP_OBJ:
- gap = ap;
- break;
- case ACL_MASK: /* more than just standard modes */
- nomask = 0;
- iattr.ia_mode |= ap->ae_perm << 3;
- *basicperms = 0;
- break;
- case ACL_OTHER:
- iattr.ia_mode |= ap->ae_perm;
- break;
- default: /* more than just standard modes */
- *basicperms = 0;
- break;
- }
- ap++;
- }
-
- /* Set the group bits from ACL_GROUP_OBJ if there's no ACL_MASK */
- if (gap && nomask)
- iattr.ia_mode |= gap->ae_perm << 3;
-
- return xfs_setattr(XFS_I(vp), &iattr, 0);
-}
-
-/*
- * The permissions for the special ACL entries (u::, g::[m::], o::) are
- * actually stored in the file mode (if there is both a group and a mask,
- * the group is stored in the ACL entry and the mask is stored on the file).
- * This allows the mode to remain automatically in sync with the ACL without
- * the need for a call-back to the ACL system at every point where the mode
- * could change. This function takes the permissions from the specified mode
- * and places it in the supplied ACL.
- *
- * This implementation draws its validity from the fact that, when the ACL
- * was assigned, the mode was copied from the ACL.
- * If the mode did not change, therefore, the mode remains exactly what was
- * taken from the special ACL entries at assignment.
- * If a subsequent chmod() was done, the POSIX spec says that the change in
- * mode must cause an update to the ACL seen at user level and used for
- * access checks. Before and after a mode change, therefore, the file mode
- * most accurately reflects what the special ACL entries should permit/deny.
- *
- * CAVEAT: If someone sets the SGI_ACL_FILE attribute directly,
- * the existing mode bits will override whatever is in the
- * ACL. Similarly, if there is a pre-existing ACL that was
- * never in sync with its mode (owing to a bug in 6.5 and
- * before), it will now magically (or mystically) be
- * synchronized. This could cause slight astonishment, but
- * it is better than inconsistent permissions.
- *
- * The supplied ACL is a template that may contain any combination
- * of special entries. These are treated as place holders when we fill
- * out the ACL. This routine does not add or remove special entries, it
- * simply unites each special entry with its associated set of permissions.
- */
-STATIC void
-xfs_acl_sync_mode(
- mode_t mode,
- xfs_acl_t *acl)
-{
- int i, nomask = 1;
- xfs_acl_entry_t *ap;
- xfs_acl_entry_t *gap = NULL;
-
- /*
- * Set ACL entries. POSIX1003.1eD16 requires that the MASK
- * be set instead of the GROUP entry, if there is a MASK.
- */
- for (ap = acl->acl_entry, i = 0; i < acl->acl_cnt; ap++, i++) {
- switch (ap->ae_tag) {
- case ACL_USER_OBJ:
- ap->ae_perm = (mode >> 6) & 0x7;
- break;
- case ACL_GROUP_OBJ:
- gap = ap;
- break;
- case ACL_MASK:
- nomask = 0;
- ap->ae_perm = (mode >> 3) & 0x7;
- break;
- case ACL_OTHER:
- ap->ae_perm = mode & 0x7;
- break;
- default:
- break;
- }
- }
- /* Set the ACL_GROUP_OBJ if there's no ACL_MASK */
- if (gap && nomask)
- gap->ae_perm = (mode >> 3) & 0x7;
-}
-
-/*
- * When inheriting an Access ACL from a directory Default ACL,
- * the ACL bits are set to the intersection of the ACL default
- * permission bits and the file permission bits in mode. If there
- * are no permission bits on the file then we must not give them
- * the ACL. This is what what makes umask() work with ACLs.
- */
-STATIC void
-xfs_acl_filter_mode(
- mode_t mode,
- xfs_acl_t *acl)
-{
- int i, nomask = 1;
- xfs_acl_entry_t *ap;
- xfs_acl_entry_t *gap = NULL;
-
- /*
- * Set ACL entries. POSIX1003.1eD16 requires that the MASK
- * be merged with GROUP entry, if there is a MASK.
- */
- for (ap = acl->acl_entry, i = 0; i < acl->acl_cnt; ap++, i++) {
- switch (ap->ae_tag) {
- case ACL_USER_OBJ:
- ap->ae_perm &= (mode >> 6) & 0x7;
- break;
- case ACL_GROUP_OBJ:
- gap = ap;
- break;
- case ACL_MASK:
- nomask = 0;
- ap->ae_perm &= (mode >> 3) & 0x7;
- break;
- case ACL_OTHER:
- ap->ae_perm &= mode & 0x7;
- break;
- default:
- break;
- }
- }
- /* Set the ACL_GROUP_OBJ if there's no ACL_MASK */
- if (gap && nomask)
- gap->ae_perm &= (mode >> 3) & 0x7;
-}
git.openpandora.org / pandora-kernel.git / blobdiff