summaryrefslogtreecommitdiffstats
path: root/fs/nfsd/nfs4acl.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/nfsd/nfs4acl.c')
-rw-r--r--fs/nfsd/nfs4acl.c954
1 files changed, 954 insertions, 0 deletions
diff --git a/fs/nfsd/nfs4acl.c b/fs/nfsd/nfs4acl.c
new file mode 100644
index 00000000000..11ebf6c4aa5
--- /dev/null
+++ b/fs/nfsd/nfs4acl.c
@@ -0,0 +1,954 @@
+/*
+ * 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);
+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 -1;
+ if ((n4acl->naces - 7) % 3)
+ return -1;
+ 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;
+}
+
+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) == -1;
+ 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 -1;
+
+ 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 < sizeof(s2t_map) / sizeof(*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 < sizeof(s2t_map) / sizeof(*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);