diff options
author | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2009-06-15 10:36:54 +1000 |
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committer | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2009-06-15 10:36:54 +1000 |
commit | 7dafd239ab522d38979ebe44d79aa68ad7b1a383 (patch) | |
tree | 04754a0c6495e57c1fe5f417fbfc99272d353c0e /fs/xfs/xfs_acl.c | |
parent | bc47ab0241c7c86da4f5e5f82fbca7d45387c18d (diff) | |
parent | 45e3e1935e2857c54783291107d33323b3ef33c8 (diff) |
Merge commit 'origin/master' into next
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; -} |