linux/fs/nfsd/nfs4acl.c
NeilBrown b905b7b0a0 [PATCH] knfsd: nfsd4: better nfs4acl errors
We're returning -1 in a few places in the NFSv4<->POSIX acl translation code
where we could return a reasonable error.

Also allows some minor simplification elsewhere.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-04-11 06:18:51 -07:00

954 lines
22 KiB
C

/*
* fs/nfs4acl/acl.c
*
* Common NFSv4 ACL handling code.
*
* Copyright (c) 2002, 2003 The Regents of the University of Michigan.
* All rights reserved.
*
* Marius Aamodt Eriksen <marius@umich.edu>
* Jeff Sedlak <jsedlak@umich.edu>
* J. Bruce Fields <bfields@umich.edu>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
* BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/list.h>
#include <linux/types.h>
#include <linux/fs.h>
#include <linux/module.h>
#include <linux/nfs_fs.h>
#include <linux/posix_acl.h>
#include <linux/nfs4.h>
#include <linux/nfs4_acl.h>
/* mode bit translations: */
#define NFS4_READ_MODE (NFS4_ACE_READ_DATA)
#define NFS4_WRITE_MODE (NFS4_ACE_WRITE_DATA | NFS4_ACE_APPEND_DATA)
#define NFS4_EXECUTE_MODE NFS4_ACE_EXECUTE
#define NFS4_ANYONE_MODE (NFS4_ACE_READ_ATTRIBUTES | NFS4_ACE_READ_ACL | NFS4_ACE_SYNCHRONIZE)
#define NFS4_OWNER_MODE (NFS4_ACE_WRITE_ATTRIBUTES | NFS4_ACE_WRITE_ACL)
/* We don't support these bits; insist they be neither allowed nor denied */
#define NFS4_MASK_UNSUPP (NFS4_ACE_DELETE | NFS4_ACE_WRITE_OWNER \
| NFS4_ACE_READ_NAMED_ATTRS | NFS4_ACE_WRITE_NAMED_ATTRS)
/* flags used to simulate posix default ACLs */
#define NFS4_INHERITANCE_FLAGS (NFS4_ACE_FILE_INHERIT_ACE \
| NFS4_ACE_DIRECTORY_INHERIT_ACE | NFS4_ACE_INHERIT_ONLY_ACE)
#define MASK_EQUAL(mask1, mask2) \
( ((mask1) & NFS4_ACE_MASK_ALL) == ((mask2) & NFS4_ACE_MASK_ALL) )
static u32
mask_from_posix(unsigned short perm, unsigned int flags)
{
int mask = NFS4_ANYONE_MODE;
if (flags & NFS4_ACL_OWNER)
mask |= NFS4_OWNER_MODE;
if (perm & ACL_READ)
mask |= NFS4_READ_MODE;
if (perm & ACL_WRITE)
mask |= NFS4_WRITE_MODE;
if ((perm & ACL_WRITE) && (flags & NFS4_ACL_DIR))
mask |= NFS4_ACE_DELETE_CHILD;
if (perm & ACL_EXECUTE)
mask |= NFS4_EXECUTE_MODE;
return mask;
}
static u32
deny_mask(u32 allow_mask, unsigned int flags)
{
u32 ret = ~allow_mask & ~NFS4_MASK_UNSUPP;
if (!(flags & NFS4_ACL_DIR))
ret &= ~NFS4_ACE_DELETE_CHILD;
return ret;
}
/* XXX: modify functions to return NFS errors; they're only ever
* used by nfs code, after all.... */
static int
mode_from_nfs4(u32 perm, unsigned short *mode, unsigned int flags)
{
u32 ignore = 0;
if (!(flags & NFS4_ACL_DIR))
ignore |= NFS4_ACE_DELETE_CHILD; /* ignore it */
perm |= ignore;
*mode = 0;
if ((perm & NFS4_READ_MODE) == NFS4_READ_MODE)
*mode |= ACL_READ;
if ((perm & NFS4_WRITE_MODE) == NFS4_WRITE_MODE)
*mode |= ACL_WRITE;
if ((perm & NFS4_EXECUTE_MODE) == NFS4_EXECUTE_MODE)
*mode |= ACL_EXECUTE;
if (!MASK_EQUAL(perm, ignore|mask_from_posix(*mode, flags)))
return -EINVAL;
return 0;
}
struct ace_container {
struct nfs4_ace *ace;
struct list_head ace_l;
};
static short ace2type(struct nfs4_ace *);
static int _posix_to_nfsv4_one(struct posix_acl *, struct nfs4_acl *, unsigned int);
static struct posix_acl *_nfsv4_to_posix_one(struct nfs4_acl *, unsigned int);
int nfs4_acl_add_ace(struct nfs4_acl *, u32, u32, u32, int, uid_t);
static int nfs4_acl_split(struct nfs4_acl *, struct nfs4_acl *);
struct nfs4_acl *
nfs4_acl_posix_to_nfsv4(struct posix_acl *pacl, struct posix_acl *dpacl,
unsigned int flags)
{
struct nfs4_acl *acl;
int error = -EINVAL;
if ((pacl != NULL &&
(posix_acl_valid(pacl) < 0 || pacl->a_count == 0)) ||
(dpacl != NULL &&
(posix_acl_valid(dpacl) < 0 || dpacl->a_count == 0)))
goto out_err;
acl = nfs4_acl_new();
if (acl == NULL) {
error = -ENOMEM;
goto out_err;
}
if (pacl != NULL) {
error = _posix_to_nfsv4_one(pacl, acl,
flags & ~NFS4_ACL_TYPE_DEFAULT);
if (error < 0)
goto out_acl;
}
if (dpacl != NULL) {
error = _posix_to_nfsv4_one(dpacl, acl,
flags | NFS4_ACL_TYPE_DEFAULT);
if (error < 0)
goto out_acl;
}
return acl;
out_acl:
nfs4_acl_free(acl);
out_err:
acl = ERR_PTR(error);
return acl;
}
static int
nfs4_acl_add_pair(struct nfs4_acl *acl, int eflag, u32 mask, int whotype,
uid_t owner, unsigned int flags)
{
int error;
error = nfs4_acl_add_ace(acl, NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE,
eflag, mask, whotype, owner);
if (error < 0)
return error;
error = nfs4_acl_add_ace(acl, NFS4_ACE_ACCESS_DENIED_ACE_TYPE,
eflag, deny_mask(mask, flags), whotype, owner);
return error;
}
/* We assume the acl has been verified with posix_acl_valid. */
static int
_posix_to_nfsv4_one(struct posix_acl *pacl, struct nfs4_acl *acl,
unsigned int flags)
{
struct posix_acl_entry *pa, *pe, *group_owner_entry;
int error = -EINVAL;
u32 mask, mask_mask;
int eflag = ((flags & NFS4_ACL_TYPE_DEFAULT) ?
NFS4_INHERITANCE_FLAGS : 0);
BUG_ON(pacl->a_count < 3);
pe = pacl->a_entries + pacl->a_count;
pa = pe - 2; /* if mask entry exists, it's second from the last. */
if (pa->e_tag == ACL_MASK)
mask_mask = deny_mask(mask_from_posix(pa->e_perm, flags), flags);
else
mask_mask = 0;
pa = pacl->a_entries;
BUG_ON(pa->e_tag != ACL_USER_OBJ);
mask = mask_from_posix(pa->e_perm, flags | NFS4_ACL_OWNER);
error = nfs4_acl_add_pair(acl, eflag, mask, NFS4_ACL_WHO_OWNER, 0, flags);
if (error < 0)
goto out;
pa++;
while (pa->e_tag == ACL_USER) {
mask = mask_from_posix(pa->e_perm, flags);
error = nfs4_acl_add_ace(acl, NFS4_ACE_ACCESS_DENIED_ACE_TYPE,
eflag, mask_mask, NFS4_ACL_WHO_NAMED, pa->e_id);
if (error < 0)
goto out;
error = nfs4_acl_add_pair(acl, eflag, mask,
NFS4_ACL_WHO_NAMED, pa->e_id, flags);
if (error < 0)
goto out;
pa++;
}
/* In the case of groups, we apply allow ACEs first, then deny ACEs,
* since a user can be in more than one group. */
/* allow ACEs */
if (pacl->a_count > 3) {
BUG_ON(pa->e_tag != ACL_GROUP_OBJ);
error = nfs4_acl_add_ace(acl, NFS4_ACE_ACCESS_DENIED_ACE_TYPE,
NFS4_ACE_IDENTIFIER_GROUP | eflag, mask_mask,
NFS4_ACL_WHO_GROUP, 0);
if (error < 0)
goto out;
}
group_owner_entry = pa;
mask = mask_from_posix(pa->e_perm, flags);
error = nfs4_acl_add_ace(acl, NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE,
NFS4_ACE_IDENTIFIER_GROUP | eflag, mask,
NFS4_ACL_WHO_GROUP, 0);
if (error < 0)
goto out;
pa++;
while (pa->e_tag == ACL_GROUP) {
mask = mask_from_posix(pa->e_perm, flags);
error = nfs4_acl_add_ace(acl, NFS4_ACE_ACCESS_DENIED_ACE_TYPE,
NFS4_ACE_IDENTIFIER_GROUP | eflag, mask_mask,
NFS4_ACL_WHO_NAMED, pa->e_id);
if (error < 0)
goto out;
error = nfs4_acl_add_ace(acl, NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE,
NFS4_ACE_IDENTIFIER_GROUP | eflag, mask,
NFS4_ACL_WHO_NAMED, pa->e_id);
if (error < 0)
goto out;
pa++;
}
/* deny ACEs */
pa = group_owner_entry;
mask = mask_from_posix(pa->e_perm, flags);
error = nfs4_acl_add_ace(acl, NFS4_ACE_ACCESS_DENIED_ACE_TYPE,
NFS4_ACE_IDENTIFIER_GROUP | eflag,
deny_mask(mask, flags), NFS4_ACL_WHO_GROUP, 0);
if (error < 0)
goto out;
pa++;
while (pa->e_tag == ACL_GROUP) {
mask = mask_from_posix(pa->e_perm, flags);
error = nfs4_acl_add_ace(acl, NFS4_ACE_ACCESS_DENIED_ACE_TYPE,
NFS4_ACE_IDENTIFIER_GROUP | eflag,
deny_mask(mask, flags), NFS4_ACL_WHO_NAMED, pa->e_id);
if (error < 0)
goto out;
pa++;
}
if (pa->e_tag == ACL_MASK)
pa++;
BUG_ON(pa->e_tag != ACL_OTHER);
mask = mask_from_posix(pa->e_perm, flags);
error = nfs4_acl_add_pair(acl, eflag, mask, NFS4_ACL_WHO_EVERYONE, 0, flags);
out:
return error;
}
static void
sort_pacl_range(struct posix_acl *pacl, int start, int end) {
int sorted = 0, i;
struct posix_acl_entry tmp;
/* We just do a bubble sort; easy to do in place, and we're not
* expecting acl's to be long enough to justify anything more. */
while (!sorted) {
sorted = 1;
for (i = start; i < end; i++) {
if (pacl->a_entries[i].e_id
> pacl->a_entries[i+1].e_id) {
sorted = 0;
tmp = pacl->a_entries[i];
pacl->a_entries[i] = pacl->a_entries[i+1];
pacl->a_entries[i+1] = tmp;
}
}
}
}
static void
sort_pacl(struct posix_acl *pacl)
{
/* posix_acl_valid requires that users and groups be in order
* by uid/gid. */
int i, j;
if (pacl->a_count <= 4)
return; /* no users or groups */
i = 1;
while (pacl->a_entries[i].e_tag == ACL_USER)
i++;
sort_pacl_range(pacl, 1, i-1);
BUG_ON(pacl->a_entries[i].e_tag != ACL_GROUP_OBJ);
j = i++;
while (pacl->a_entries[j].e_tag == ACL_GROUP)
j++;
sort_pacl_range(pacl, i, j-1);
return;
}
static int
write_pace(struct nfs4_ace *ace, struct posix_acl *pacl,
struct posix_acl_entry **pace, short tag, unsigned int flags)
{
struct posix_acl_entry *this = *pace;
if (*pace == pacl->a_entries + pacl->a_count)
return -EINVAL; /* fell off the end */
(*pace)++;
this->e_tag = tag;
if (tag == ACL_USER_OBJ)
flags |= NFS4_ACL_OWNER;
if (mode_from_nfs4(ace->access_mask, &this->e_perm, flags))
return -EINVAL;
this->e_id = (tag == ACL_USER || tag == ACL_GROUP ?
ace->who : ACL_UNDEFINED_ID);
return 0;
}
static struct nfs4_ace *
get_next_v4_ace(struct list_head **p, struct list_head *head)
{
struct nfs4_ace *ace;
*p = (*p)->next;
if (*p == head)
return NULL;
ace = list_entry(*p, struct nfs4_ace, l_ace);
return ace;
}
int
nfs4_acl_nfsv4_to_posix(struct nfs4_acl *acl, struct posix_acl **pacl,
struct posix_acl **dpacl, unsigned int flags)
{
struct nfs4_acl *dacl;
int error = -ENOMEM;
*pacl = NULL;
*dpacl = NULL;
dacl = nfs4_acl_new();
if (dacl == NULL)
goto out;
error = nfs4_acl_split(acl, dacl);
if (error < 0)
goto out_acl;
if (pacl != NULL) {
if (acl->naces == 0) {
error = -ENODATA;
goto try_dpacl;
}
*pacl = _nfsv4_to_posix_one(acl, flags);
if (IS_ERR(*pacl)) {
error = PTR_ERR(*pacl);
*pacl = NULL;
goto out_acl;
}
}
try_dpacl:
if (dpacl != NULL) {
if (dacl->naces == 0) {
if (pacl == NULL || *pacl == NULL)
error = -ENODATA;
goto out_acl;
}
error = 0;
*dpacl = _nfsv4_to_posix_one(dacl, flags);
if (IS_ERR(*dpacl)) {
error = PTR_ERR(*dpacl);
*dpacl = NULL;
goto out_acl;
}
}
out_acl:
if (error && pacl) {
posix_acl_release(*pacl);
*pacl = NULL;
}
nfs4_acl_free(dacl);
out:
return error;
}
static int
same_who(struct nfs4_ace *a, struct nfs4_ace *b)
{
return a->whotype == b->whotype &&
(a->whotype != NFS4_ACL_WHO_NAMED || a->who == b->who);
}
static int
complementary_ace_pair(struct nfs4_ace *allow, struct nfs4_ace *deny,
unsigned int flags)
{
int ignore = 0;
if (!(flags & NFS4_ACL_DIR))
ignore |= NFS4_ACE_DELETE_CHILD;
return MASK_EQUAL(ignore|deny_mask(allow->access_mask, flags),
ignore|deny->access_mask) &&
allow->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE &&
deny->type == NFS4_ACE_ACCESS_DENIED_ACE_TYPE &&
allow->flag == deny->flag &&
same_who(allow, deny);
}
static inline int
user_obj_from_v4(struct nfs4_acl *n4acl, struct list_head **p,
struct posix_acl *pacl, struct posix_acl_entry **pace,
unsigned int flags)
{
int error = -EINVAL;
struct nfs4_ace *ace, *ace2;
ace = get_next_v4_ace(p, &n4acl->ace_head);
if (ace == NULL)
goto out;
if (ace2type(ace) != ACL_USER_OBJ)
goto out;
error = write_pace(ace, pacl, pace, ACL_USER_OBJ, flags);
if (error < 0)
goto out;
error = -EINVAL;
ace2 = get_next_v4_ace(p, &n4acl->ace_head);
if (ace2 == NULL)
goto out;
if (!complementary_ace_pair(ace, ace2, flags))
goto out;
error = 0;
out:
return error;
}
static inline int
users_from_v4(struct nfs4_acl *n4acl, struct list_head **p,
struct nfs4_ace **mask_ace,
struct posix_acl *pacl, struct posix_acl_entry **pace,
unsigned int flags)
{
int error = -EINVAL;
struct nfs4_ace *ace, *ace2;
ace = get_next_v4_ace(p, &n4acl->ace_head);
if (ace == NULL)
goto out;
while (ace2type(ace) == ACL_USER) {
if (ace->type != NFS4_ACE_ACCESS_DENIED_ACE_TYPE)
goto out;
if (*mask_ace &&
!MASK_EQUAL(ace->access_mask, (*mask_ace)->access_mask))
goto out;
*mask_ace = ace;
ace = get_next_v4_ace(p, &n4acl->ace_head);
if (ace == NULL)
goto out;
if (ace->type != NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE)
goto out;
error = write_pace(ace, pacl, pace, ACL_USER, flags);
if (error < 0)
goto out;
error = -EINVAL;
ace2 = get_next_v4_ace(p, &n4acl->ace_head);
if (ace2 == NULL)
goto out;
if (!complementary_ace_pair(ace, ace2, flags))
goto out;
if ((*mask_ace)->flag != ace2->flag ||
!same_who(*mask_ace, ace2))
goto out;
ace = get_next_v4_ace(p, &n4acl->ace_head);
if (ace == NULL)
goto out;
}
error = 0;
out:
return error;
}
static inline int
group_obj_and_groups_from_v4(struct nfs4_acl *n4acl, struct list_head **p,
struct nfs4_ace **mask_ace,
struct posix_acl *pacl, struct posix_acl_entry **pace,
unsigned int flags)
{
int error = -EINVAL;
struct nfs4_ace *ace, *ace2;
struct ace_container *ac;
struct list_head group_l;
INIT_LIST_HEAD(&group_l);
ace = list_entry(*p, struct nfs4_ace, l_ace);
/* group owner (mask and allow aces) */
if (pacl->a_count != 3) {
/* then the group owner should be preceded by mask */
if (ace->type != NFS4_ACE_ACCESS_DENIED_ACE_TYPE)
goto out;
if (*mask_ace &&
!MASK_EQUAL(ace->access_mask, (*mask_ace)->access_mask))
goto out;
*mask_ace = ace;
ace = get_next_v4_ace(p, &n4acl->ace_head);
if (ace == NULL)
goto out;
if ((*mask_ace)->flag != ace->flag || !same_who(*mask_ace, ace))
goto out;
}
if (ace2type(ace) != ACL_GROUP_OBJ)
goto out;
ac = kmalloc(sizeof(*ac), GFP_KERNEL);
error = -ENOMEM;
if (ac == NULL)
goto out;
ac->ace = ace;
list_add_tail(&ac->ace_l, &group_l);
error = -EINVAL;
if (ace->type != NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE)
goto out;
error = write_pace(ace, pacl, pace, ACL_GROUP_OBJ, flags);
if (error < 0)
goto out;
error = -EINVAL;
ace = get_next_v4_ace(p, &n4acl->ace_head);
if (ace == NULL)
goto out;
/* groups (mask and allow aces) */
while (ace2type(ace) == ACL_GROUP) {
if (*mask_ace == NULL)
goto out;
if (ace->type != NFS4_ACE_ACCESS_DENIED_ACE_TYPE ||
!MASK_EQUAL(ace->access_mask, (*mask_ace)->access_mask))
goto out;
*mask_ace = ace;
ace = get_next_v4_ace(p, &n4acl->ace_head);
if (ace == NULL)
goto out;
ac = kmalloc(sizeof(*ac), GFP_KERNEL);
error = -ENOMEM;
if (ac == NULL)
goto out;
error = -EINVAL;
if (ace->type != NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE ||
!same_who(ace, *mask_ace))
goto out;
ac->ace = ace;
list_add_tail(&ac->ace_l, &group_l);
error = write_pace(ace, pacl, pace, ACL_GROUP, flags);
if (error < 0)
goto out;
error = -EINVAL;
ace = get_next_v4_ace(p, &n4acl->ace_head);
if (ace == NULL)
goto out;
}
/* group owner (deny ace) */
if (ace2type(ace) != ACL_GROUP_OBJ)
goto out;
ac = list_entry(group_l.next, struct ace_container, ace_l);
ace2 = ac->ace;
if (!complementary_ace_pair(ace2, ace, flags))
goto out;
list_del(group_l.next);
kfree(ac);
/* groups (deny aces) */
while (!list_empty(&group_l)) {
ace = get_next_v4_ace(p, &n4acl->ace_head);
if (ace == NULL)
goto out;
if (ace2type(ace) != ACL_GROUP)
goto out;
ac = list_entry(group_l.next, struct ace_container, ace_l);
ace2 = ac->ace;
if (!complementary_ace_pair(ace2, ace, flags))
goto out;
list_del(group_l.next);
kfree(ac);
}
ace = get_next_v4_ace(p, &n4acl->ace_head);
if (ace == NULL)
goto out;
if (ace2type(ace) != ACL_OTHER)
goto out;
error = 0;
out:
while (!list_empty(&group_l)) {
ac = list_entry(group_l.next, struct ace_container, ace_l);
list_del(group_l.next);
kfree(ac);
}
return error;
}
static inline int
mask_from_v4(struct nfs4_acl *n4acl, struct list_head **p,
struct nfs4_ace **mask_ace,
struct posix_acl *pacl, struct posix_acl_entry **pace,
unsigned int flags)
{
int error = -EINVAL;
struct nfs4_ace *ace;
ace = list_entry(*p, struct nfs4_ace, l_ace);
if (pacl->a_count != 3) {
if (*mask_ace == NULL)
goto out;
(*mask_ace)->access_mask = deny_mask((*mask_ace)->access_mask, flags);
write_pace(*mask_ace, pacl, pace, ACL_MASK, flags);
}
error = 0;
out:
return error;
}
static inline int
other_from_v4(struct nfs4_acl *n4acl, struct list_head **p,
struct posix_acl *pacl, struct posix_acl_entry **pace,
unsigned int flags)
{
int error = -EINVAL;
struct nfs4_ace *ace, *ace2;
ace = list_entry(*p, struct nfs4_ace, l_ace);
if (ace->type != NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE)
goto out;
error = write_pace(ace, pacl, pace, ACL_OTHER, flags);
if (error < 0)
goto out;
error = -EINVAL;
ace2 = get_next_v4_ace(p, &n4acl->ace_head);
if (ace2 == NULL)
goto out;
if (!complementary_ace_pair(ace, ace2, flags))
goto out;
error = 0;
out:
return error;
}
static int
calculate_posix_ace_count(struct nfs4_acl *n4acl)
{
if (n4acl->naces == 6) /* owner, owner group, and other only */
return 3;
else { /* Otherwise there must be a mask entry. */
/* Also, the remaining entries are for named users and
* groups, and come in threes (mask, allow, deny): */
if (n4acl->naces < 7)
return -EINVAL;
if ((n4acl->naces - 7) % 3)
return -EINVAL;
return 4 + (n4acl->naces - 7)/3;
}
}
static struct posix_acl *
_nfsv4_to_posix_one(struct nfs4_acl *n4acl, unsigned int flags)
{
struct posix_acl *pacl;
int error = -EINVAL, nace = 0;
struct list_head *p;
struct nfs4_ace *mask_ace = NULL;
struct posix_acl_entry *pace;
nace = calculate_posix_ace_count(n4acl);
if (nace < 0)
goto out_err;
pacl = posix_acl_alloc(nace, GFP_KERNEL);
error = -ENOMEM;
if (pacl == NULL)
goto out_err;
pace = &pacl->a_entries[0];
p = &n4acl->ace_head;
error = user_obj_from_v4(n4acl, &p, pacl, &pace, flags);
if (error)
goto out_acl;
error = users_from_v4(n4acl, &p, &mask_ace, pacl, &pace, flags);
if (error)
goto out_acl;
error = group_obj_and_groups_from_v4(n4acl, &p, &mask_ace, pacl, &pace,
flags);
if (error)
goto out_acl;
error = mask_from_v4(n4acl, &p, &mask_ace, pacl, &pace, flags);
if (error)
goto out_acl;
error = other_from_v4(n4acl, &p, pacl, &pace, flags);
if (error)
goto out_acl;
error = -EINVAL;
if (p->next != &n4acl->ace_head)
goto out_acl;
if (pace != pacl->a_entries + pacl->a_count)
goto out_acl;
sort_pacl(pacl);
return pacl;
out_acl:
posix_acl_release(pacl);
out_err:
pacl = ERR_PTR(error);
return pacl;
}
static int
nfs4_acl_split(struct nfs4_acl *acl, struct nfs4_acl *dacl)
{
struct list_head *h, *n;
struct nfs4_ace *ace;
int error = 0;
list_for_each_safe(h, n, &acl->ace_head) {
ace = list_entry(h, struct nfs4_ace, l_ace);
if ((ace->flag & NFS4_INHERITANCE_FLAGS)
!= NFS4_INHERITANCE_FLAGS)
continue;
error = nfs4_acl_add_ace(dacl, ace->type, ace->flag,
ace->access_mask, ace->whotype, ace->who);
if (error < 0)
goto out;
list_del(h);
kfree(ace);
acl->naces--;
}
out:
return error;
}
static short
ace2type(struct nfs4_ace *ace)
{
switch (ace->whotype) {
case NFS4_ACL_WHO_NAMED:
return (ace->flag & NFS4_ACE_IDENTIFIER_GROUP ?
ACL_GROUP : ACL_USER);
case NFS4_ACL_WHO_OWNER:
return ACL_USER_OBJ;
case NFS4_ACL_WHO_GROUP:
return ACL_GROUP_OBJ;
case NFS4_ACL_WHO_EVERYONE:
return ACL_OTHER;
}
BUG();
return -1;
}
EXPORT_SYMBOL(nfs4_acl_posix_to_nfsv4);
EXPORT_SYMBOL(nfs4_acl_nfsv4_to_posix);
struct nfs4_acl *
nfs4_acl_new(void)
{
struct nfs4_acl *acl;
if ((acl = kmalloc(sizeof(*acl), GFP_KERNEL)) == NULL)
return NULL;
acl->naces = 0;
INIT_LIST_HEAD(&acl->ace_head);
return acl;
}
void
nfs4_acl_free(struct nfs4_acl *acl)
{
struct list_head *h;
struct nfs4_ace *ace;
if (!acl)
return;
while (!list_empty(&acl->ace_head)) {
h = acl->ace_head.next;
list_del(h);
ace = list_entry(h, struct nfs4_ace, l_ace);
kfree(ace);
}
kfree(acl);
return;
}
int
nfs4_acl_add_ace(struct nfs4_acl *acl, u32 type, u32 flag, u32 access_mask,
int whotype, uid_t who)
{
struct nfs4_ace *ace;
if ((ace = kmalloc(sizeof(*ace), GFP_KERNEL)) == NULL)
return -ENOMEM;
ace->type = type;
ace->flag = flag;
ace->access_mask = access_mask;
ace->whotype = whotype;
ace->who = who;
list_add_tail(&ace->l_ace, &acl->ace_head);
acl->naces++;
return 0;
}
static struct {
char *string;
int stringlen;
int type;
} s2t_map[] = {
{
.string = "OWNER@",
.stringlen = sizeof("OWNER@") - 1,
.type = NFS4_ACL_WHO_OWNER,
},
{
.string = "GROUP@",
.stringlen = sizeof("GROUP@") - 1,
.type = NFS4_ACL_WHO_GROUP,
},
{
.string = "EVERYONE@",
.stringlen = sizeof("EVERYONE@") - 1,
.type = NFS4_ACL_WHO_EVERYONE,
},
};
int
nfs4_acl_get_whotype(char *p, u32 len)
{
int i;
for (i = 0; i < ARRAY_SIZE(s2t_map); i++) {
if (s2t_map[i].stringlen == len &&
0 == memcmp(s2t_map[i].string, p, len))
return s2t_map[i].type;
}
return NFS4_ACL_WHO_NAMED;
}
int
nfs4_acl_write_who(int who, char *p)
{
int i;
for (i = 0; i < ARRAY_SIZE(s2t_map); i++) {
if (s2t_map[i].type == who) {
memcpy(p, s2t_map[i].string, s2t_map[i].stringlen);
return s2t_map[i].stringlen;
}
}
BUG();
return -1;
}
static inline int
match_who(struct nfs4_ace *ace, uid_t owner, gid_t group, uid_t who)
{
switch (ace->whotype) {
case NFS4_ACL_WHO_NAMED:
return who == ace->who;
case NFS4_ACL_WHO_OWNER:
return who == owner;
case NFS4_ACL_WHO_GROUP:
return who == group;
case NFS4_ACL_WHO_EVERYONE:
return 1;
default:
return 0;
}
}
EXPORT_SYMBOL(nfs4_acl_new);
EXPORT_SYMBOL(nfs4_acl_free);
EXPORT_SYMBOL(nfs4_acl_add_ace);
EXPORT_SYMBOL(nfs4_acl_get_whotype);
EXPORT_SYMBOL(nfs4_acl_write_who);