diff options
author | Christoph Hellwig <hch@lst.de> | 2009-06-10 17:07:47 +0200 |
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committer | Christoph Hellwig <hch@brick.lst.de> | 2009-06-10 17:07:47 +0200 |
commit | ef14f0c1578dce4b688726eb2603e50b62d6665a (patch) | |
tree | 5a221081850fab8f96455745e90f4a0e2127bce0 /fs/xfs/xfs_acl.c | |
parent | 8b5403a6d772d340541cfb30a668fde119c40ac1 (diff) |
xfs: use generic Posix ACL code
This patch rips out the XFS ACL handling code and uses the generic
fs/posix_acl.c code instead. The ondisk format is of course left
unchanged.
This also introduces the same ACL caching all other Linux filesystems do
by adding pointers to the acl and default acl in struct xfs_inode.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
Diffstat (limited to 'fs/xfs/xfs_acl.c')
-rw-r--r-- | fs/xfs/xfs_acl.c | 874 |
1 files changed, 0 insertions, 874 deletions
diff --git a/fs/xfs/xfs_acl.c b/fs/xfs/xfs_acl.c deleted file mode 100644 index a8cdd73999a..00000000000 --- a/fs/xfs/xfs_acl.c +++ /dev/null @@ -1,874 +0,0 @@ -/* - * 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; -} |