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-rw-r--r--fs/nfsd/nfs4acl.c877
1 files changed, 877 insertions, 0 deletions
diff --git a/fs/nfsd/nfs4acl.c b/fs/nfsd/nfs4acl.c
new file mode 100644
index 0000000000..96e786b5e5
--- /dev/null
+++ b/fs/nfsd/nfs4acl.c
@@ -0,0 +1,877 @@
+/*
+ * 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/fs.h>
+#include <linux/slab.h>
+#include <linux/posix_acl.h>
+
+#include "nfsfh.h"
+#include "nfsd.h"
+#include "acl.h"
+#include "vfs.h"
+
+#define NFS4_ACL_TYPE_DEFAULT 0x01
+#define NFS4_ACL_DIR 0x02
+#define NFS4_ACL_OWNER 0x04
+
+/* 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)
+
+/* flags used to simulate posix default ACLs */
+#define NFS4_INHERITANCE_FLAGS (NFS4_ACE_FILE_INHERIT_ACE \
+ | NFS4_ACE_DIRECTORY_INHERIT_ACE)
+
+#define NFS4_SUPPORTED_FLAGS (NFS4_INHERITANCE_FLAGS \
+ | NFS4_ACE_INHERIT_ONLY_ACE \
+ | NFS4_ACE_IDENTIFIER_GROUP)
+
+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_from_posix(unsigned short perm, u32 flags)
+{
+ u32 mask = 0;
+
+ 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;
+}
+
+/* XXX: modify functions to return NFS errors; they're only ever
+ * used by nfs code, after all.... */
+
+/* We only map from NFSv4 to POSIX ACLs when setting ACLs, when we err on the
+ * side of being more restrictive, so the mode bit mapping below is
+ * pessimistic. An optimistic version would be needed to handle DENY's,
+ * but we expect to coalesce all ALLOWs and DENYs before mapping to mode
+ * bits. */
+
+static void
+low_mode_from_nfs4(u32 perm, unsigned short *mode, unsigned int flags)
+{
+ u32 write_mode = NFS4_WRITE_MODE;
+
+ if (flags & NFS4_ACL_DIR)
+ write_mode |= NFS4_ACE_DELETE_CHILD;
+ *mode = 0;
+ if ((perm & NFS4_READ_MODE) == NFS4_READ_MODE)
+ *mode |= ACL_READ;
+ if ((perm & write_mode) == write_mode)
+ *mode |= ACL_WRITE;
+ if ((perm & NFS4_EXECUTE_MODE) == NFS4_EXECUTE_MODE)
+ *mode |= ACL_EXECUTE;
+}
+
+static short ace2type(struct nfs4_ace *);
+static void _posix_to_nfsv4_one(struct posix_acl *, struct nfs4_acl *,
+ unsigned int);
+
+int
+nfsd4_get_nfs4_acl(struct svc_rqst *rqstp, struct dentry *dentry,
+ struct nfs4_acl **acl)
+{
+ struct inode *inode = d_inode(dentry);
+ int error = 0;
+ struct posix_acl *pacl = NULL, *dpacl = NULL;
+ unsigned int flags = 0;
+ int size = 0;
+
+ pacl = get_inode_acl(inode, ACL_TYPE_ACCESS);
+ if (!pacl)
+ pacl = posix_acl_from_mode(inode->i_mode, GFP_KERNEL);
+
+ if (IS_ERR(pacl))
+ return PTR_ERR(pacl);
+
+ /* allocate for worst case: one (deny, allow) pair each: */
+ size += 2 * pacl->a_count;
+
+ if (S_ISDIR(inode->i_mode)) {
+ flags = NFS4_ACL_DIR;
+ dpacl = get_inode_acl(inode, ACL_TYPE_DEFAULT);
+ if (IS_ERR(dpacl)) {
+ error = PTR_ERR(dpacl);
+ goto rel_pacl;
+ }
+
+ if (dpacl)
+ size += 2 * dpacl->a_count;
+ }
+
+ *acl = kmalloc(nfs4_acl_bytes(size), GFP_KERNEL);
+ if (*acl == NULL) {
+ error = -ENOMEM;
+ goto out;
+ }
+ (*acl)->naces = 0;
+
+ _posix_to_nfsv4_one(pacl, *acl, flags & ~NFS4_ACL_TYPE_DEFAULT);
+
+ if (dpacl)
+ _posix_to_nfsv4_one(dpacl, *acl, flags | NFS4_ACL_TYPE_DEFAULT);
+
+out:
+ posix_acl_release(dpacl);
+rel_pacl:
+ posix_acl_release(pacl);
+ return error;
+}
+
+struct posix_acl_summary {
+ unsigned short owner;
+ unsigned short users;
+ unsigned short group;
+ unsigned short groups;
+ unsigned short other;
+ unsigned short mask;
+};
+
+static void
+summarize_posix_acl(struct posix_acl *acl, struct posix_acl_summary *pas)
+{
+ struct posix_acl_entry *pa, *pe;
+
+ /*
+ * Only pas.users and pas.groups need initialization; previous
+ * posix_acl_valid() calls ensure that the other fields will be
+ * initialized in the following loop. But, just to placate gcc:
+ */
+ memset(pas, 0, sizeof(*pas));
+ pas->mask = 07;
+
+ pe = acl->a_entries + acl->a_count;
+
+ FOREACH_ACL_ENTRY(pa, acl, pe) {
+ switch (pa->e_tag) {
+ case ACL_USER_OBJ:
+ pas->owner = pa->e_perm;
+ break;
+ case ACL_GROUP_OBJ:
+ pas->group = pa->e_perm;
+ break;
+ case ACL_USER:
+ pas->users |= pa->e_perm;
+ break;
+ case ACL_GROUP:
+ pas->groups |= pa->e_perm;
+ break;
+ case ACL_OTHER:
+ pas->other = pa->e_perm;
+ break;
+ case ACL_MASK:
+ pas->mask = pa->e_perm;
+ break;
+ }
+ }
+ /* We'll only care about effective permissions: */
+ pas->users &= pas->mask;
+ pas->group &= pas->mask;
+ pas->groups &= pas->mask;
+}
+
+/* We assume the acl has been verified with posix_acl_valid. */
+static void
+_posix_to_nfsv4_one(struct posix_acl *pacl, struct nfs4_acl *acl,
+ unsigned int flags)
+{
+ struct posix_acl_entry *pa, *group_owner_entry;
+ struct nfs4_ace *ace;
+ struct posix_acl_summary pas;
+ unsigned short deny;
+ int eflag = ((flags & NFS4_ACL_TYPE_DEFAULT) ?
+ NFS4_INHERITANCE_FLAGS | NFS4_ACE_INHERIT_ONLY_ACE : 0);
+
+ BUG_ON(pacl->a_count < 3);
+ summarize_posix_acl(pacl, &pas);
+
+ pa = pacl->a_entries;
+ ace = acl->aces + acl->naces;
+
+ /* We could deny everything not granted by the owner: */
+ deny = ~pas.owner;
+ /*
+ * but it is equivalent (and simpler) to deny only what is not
+ * granted by later entries:
+ */
+ deny &= pas.users | pas.group | pas.groups | pas.other;
+ if (deny) {
+ ace->type = NFS4_ACE_ACCESS_DENIED_ACE_TYPE;
+ ace->flag = eflag;
+ ace->access_mask = deny_mask_from_posix(deny, flags);
+ ace->whotype = NFS4_ACL_WHO_OWNER;
+ ace++;
+ acl->naces++;
+ }
+
+ ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE;
+ ace->flag = eflag;
+ ace->access_mask = mask_from_posix(pa->e_perm, flags | NFS4_ACL_OWNER);
+ ace->whotype = NFS4_ACL_WHO_OWNER;
+ ace++;
+ acl->naces++;
+ pa++;
+
+ while (pa->e_tag == ACL_USER) {
+ deny = ~(pa->e_perm & pas.mask);
+ deny &= pas.groups | pas.group | pas.other;
+ if (deny) {
+ ace->type = NFS4_ACE_ACCESS_DENIED_ACE_TYPE;
+ ace->flag = eflag;
+ ace->access_mask = deny_mask_from_posix(deny, flags);
+ ace->whotype = NFS4_ACL_WHO_NAMED;
+ ace->who_uid = pa->e_uid;
+ ace++;
+ acl->naces++;
+ }
+ ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE;
+ ace->flag = eflag;
+ ace->access_mask = mask_from_posix(pa->e_perm & pas.mask,
+ flags);
+ ace->whotype = NFS4_ACL_WHO_NAMED;
+ ace->who_uid = pa->e_uid;
+ ace++;
+ acl->naces++;
+ 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 */
+
+ group_owner_entry = pa;
+
+ ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE;
+ ace->flag = eflag;
+ ace->access_mask = mask_from_posix(pas.group, flags);
+ ace->whotype = NFS4_ACL_WHO_GROUP;
+ ace++;
+ acl->naces++;
+ pa++;
+
+ while (pa->e_tag == ACL_GROUP) {
+ ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE;
+ ace->flag = eflag | NFS4_ACE_IDENTIFIER_GROUP;
+ ace->access_mask = mask_from_posix(pa->e_perm & pas.mask,
+ flags);
+ ace->whotype = NFS4_ACL_WHO_NAMED;
+ ace->who_gid = pa->e_gid;
+ ace++;
+ acl->naces++;
+ pa++;
+ }
+
+ /* deny ACEs */
+
+ pa = group_owner_entry;
+
+ deny = ~pas.group & pas.other;
+ if (deny) {
+ ace->type = NFS4_ACE_ACCESS_DENIED_ACE_TYPE;
+ ace->flag = eflag;
+ ace->access_mask = deny_mask_from_posix(deny, flags);
+ ace->whotype = NFS4_ACL_WHO_GROUP;
+ ace++;
+ acl->naces++;
+ }
+ pa++;
+
+ while (pa->e_tag == ACL_GROUP) {
+ deny = ~(pa->e_perm & pas.mask);
+ deny &= pas.other;
+ if (deny) {
+ ace->type = NFS4_ACE_ACCESS_DENIED_ACE_TYPE;
+ ace->flag = eflag | NFS4_ACE_IDENTIFIER_GROUP;
+ ace->access_mask = deny_mask_from_posix(deny, flags);
+ ace->whotype = NFS4_ACL_WHO_NAMED;
+ ace->who_gid = pa->e_gid;
+ ace++;
+ acl->naces++;
+ }
+ pa++;
+ }
+
+ if (pa->e_tag == ACL_MASK)
+ pa++;
+ ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE;
+ ace->flag = eflag;
+ ace->access_mask = mask_from_posix(pa->e_perm, flags);
+ ace->whotype = NFS4_ACL_WHO_EVERYONE;
+ acl->naces++;
+}
+
+static bool
+pace_gt(struct posix_acl_entry *pace1, struct posix_acl_entry *pace2)
+{
+ if (pace1->e_tag != pace2->e_tag)
+ return pace1->e_tag > pace2->e_tag;
+ if (pace1->e_tag == ACL_USER)
+ return uid_gt(pace1->e_uid, pace2->e_uid);
+ if (pace1->e_tag == ACL_GROUP)
+ return gid_gt(pace1->e_gid, pace2->e_gid);
+ return false;
+}
+
+static void
+sort_pacl_range(struct posix_acl *pacl, int start, int end) {
+ int sorted = 0, i;
+
+ /* 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 (pace_gt(&pacl->a_entries[i],
+ &pacl->a_entries[i+1])) {
+ sorted = 0;
+ swap(pacl->a_entries[i],
+ pacl->a_entries[i + 1]);
+ }
+ }
+ }
+}
+
+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;
+
+ /* no users or groups */
+ if (!pacl || pacl->a_count <= 4)
+ return;
+
+ 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;
+}
+
+/*
+ * While processing the NFSv4 ACE, this maintains bitmasks representing
+ * which permission bits have been allowed and which denied to a given
+ * entity: */
+struct posix_ace_state {
+ u32 allow;
+ u32 deny;
+};
+
+struct posix_user_ace_state {
+ union {
+ kuid_t uid;
+ kgid_t gid;
+ };
+ struct posix_ace_state perms;
+};
+
+struct posix_ace_state_array {
+ int n;
+ struct posix_user_ace_state aces[];
+};
+
+/*
+ * While processing the NFSv4 ACE, this maintains the partial permissions
+ * calculated so far: */
+
+struct posix_acl_state {
+ unsigned char valid;
+ struct posix_ace_state owner;
+ struct posix_ace_state group;
+ struct posix_ace_state other;
+ struct posix_ace_state everyone;
+ struct posix_ace_state mask; /* Deny unused in this case */
+ struct posix_ace_state_array *users;
+ struct posix_ace_state_array *groups;
+};
+
+static int
+init_state(struct posix_acl_state *state, int cnt)
+{
+ int alloc;
+
+ memset(state, 0, sizeof(struct posix_acl_state));
+ /*
+ * In the worst case, each individual acl could be for a distinct
+ * named user or group, but we don't know which, so we allocate
+ * enough space for either:
+ */
+ alloc = sizeof(struct posix_ace_state_array)
+ + cnt*sizeof(struct posix_user_ace_state);
+ state->users = kzalloc(alloc, GFP_KERNEL);
+ if (!state->users)
+ return -ENOMEM;
+ state->groups = kzalloc(alloc, GFP_KERNEL);
+ if (!state->groups) {
+ kfree(state->users);
+ return -ENOMEM;
+ }
+ return 0;
+}
+
+static void
+free_state(struct posix_acl_state *state) {
+ kfree(state->users);
+ kfree(state->groups);
+}
+
+static inline void add_to_mask(struct posix_acl_state *state, struct posix_ace_state *astate)
+{
+ state->mask.allow |= astate->allow;
+}
+
+static struct posix_acl *
+posix_state_to_acl(struct posix_acl_state *state, unsigned int flags)
+{
+ struct posix_acl_entry *pace;
+ struct posix_acl *pacl;
+ int nace;
+ int i;
+
+ /*
+ * ACLs with no ACEs are treated differently in the inheritable
+ * and effective cases: when there are no inheritable ACEs,
+ * calls ->set_acl with a NULL ACL structure.
+ */
+ if (!state->valid && (flags & NFS4_ACL_TYPE_DEFAULT))
+ return NULL;
+
+ /*
+ * When there are no effective ACEs, the following will end
+ * up setting a 3-element effective posix ACL with all
+ * permissions zero.
+ */
+ if (!state->users->n && !state->groups->n)
+ nace = 3;
+ else /* Note we also include a MASK ACE in this case: */
+ nace = 4 + state->users->n + state->groups->n;
+ pacl = posix_acl_alloc(nace, GFP_KERNEL);
+ if (!pacl)
+ return ERR_PTR(-ENOMEM);
+
+ pace = pacl->a_entries;
+ pace->e_tag = ACL_USER_OBJ;
+ low_mode_from_nfs4(state->owner.allow, &pace->e_perm, flags);
+
+ for (i=0; i < state->users->n; i++) {
+ pace++;
+ pace->e_tag = ACL_USER;
+ low_mode_from_nfs4(state->users->aces[i].perms.allow,
+ &pace->e_perm, flags);
+ pace->e_uid = state->users->aces[i].uid;
+ add_to_mask(state, &state->users->aces[i].perms);
+ }
+
+ pace++;
+ pace->e_tag = ACL_GROUP_OBJ;
+ low_mode_from_nfs4(state->group.allow, &pace->e_perm, flags);
+ add_to_mask(state, &state->group);
+
+ for (i=0; i < state->groups->n; i++) {
+ pace++;
+ pace->e_tag = ACL_GROUP;
+ low_mode_from_nfs4(state->groups->aces[i].perms.allow,
+ &pace->e_perm, flags);
+ pace->e_gid = state->groups->aces[i].gid;
+ add_to_mask(state, &state->groups->aces[i].perms);
+ }
+
+ if (state->users->n || state->groups->n) {
+ pace++;
+ pace->e_tag = ACL_MASK;
+ low_mode_from_nfs4(state->mask.allow, &pace->e_perm, flags);
+ }
+
+ pace++;
+ pace->e_tag = ACL_OTHER;
+ low_mode_from_nfs4(state->other.allow, &pace->e_perm, flags);
+
+ return pacl;
+}
+
+static inline void allow_bits(struct posix_ace_state *astate, u32 mask)
+{
+ /* Allow all bits in the mask not already denied: */
+ astate->allow |= mask & ~astate->deny;
+}
+
+static inline void deny_bits(struct posix_ace_state *astate, u32 mask)
+{
+ /* Deny all bits in the mask not already allowed: */
+ astate->deny |= mask & ~astate->allow;
+}
+
+static int find_uid(struct posix_acl_state *state, kuid_t uid)
+{
+ struct posix_ace_state_array *a = state->users;
+ int i;
+
+ for (i = 0; i < a->n; i++)
+ if (uid_eq(a->aces[i].uid, uid))
+ return i;
+ /* Not found: */
+ a->n++;
+ a->aces[i].uid = uid;
+ a->aces[i].perms.allow = state->everyone.allow;
+ a->aces[i].perms.deny = state->everyone.deny;
+
+ return i;
+}
+
+static int find_gid(struct posix_acl_state *state, kgid_t gid)
+{
+ struct posix_ace_state_array *a = state->groups;
+ int i;
+
+ for (i = 0; i < a->n; i++)
+ if (gid_eq(a->aces[i].gid, gid))
+ return i;
+ /* Not found: */
+ a->n++;
+ a->aces[i].gid = gid;
+ a->aces[i].perms.allow = state->everyone.allow;
+ a->aces[i].perms.deny = state->everyone.deny;
+
+ return i;
+}
+
+static void deny_bits_array(struct posix_ace_state_array *a, u32 mask)
+{
+ int i;
+
+ for (i=0; i < a->n; i++)
+ deny_bits(&a->aces[i].perms, mask);
+}
+
+static void allow_bits_array(struct posix_ace_state_array *a, u32 mask)
+{
+ int i;
+
+ for (i=0; i < a->n; i++)
+ allow_bits(&a->aces[i].perms, mask);
+}
+
+static void process_one_v4_ace(struct posix_acl_state *state,
+ struct nfs4_ace *ace)
+{
+ u32 mask = ace->access_mask;
+ short type = ace2type(ace);
+ int i;
+
+ state->valid |= type;
+
+ switch (type) {
+ case ACL_USER_OBJ:
+ if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) {
+ allow_bits(&state->owner, mask);
+ } else {
+ deny_bits(&state->owner, mask);
+ }
+ break;
+ case ACL_USER:
+ i = find_uid(state, ace->who_uid);
+ if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) {
+ allow_bits(&state->users->aces[i].perms, mask);
+ } else {
+ deny_bits(&state->users->aces[i].perms, mask);
+ mask = state->users->aces[i].perms.deny;
+ deny_bits(&state->owner, mask);
+ }
+ break;
+ case ACL_GROUP_OBJ:
+ if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) {
+ allow_bits(&state->group, mask);
+ } else {
+ deny_bits(&state->group, mask);
+ mask = state->group.deny;
+ deny_bits(&state->owner, mask);
+ deny_bits(&state->everyone, mask);
+ deny_bits_array(state->users, mask);
+ deny_bits_array(state->groups, mask);
+ }
+ break;
+ case ACL_GROUP:
+ i = find_gid(state, ace->who_gid);
+ if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) {
+ allow_bits(&state->groups->aces[i].perms, mask);
+ } else {
+ deny_bits(&state->groups->aces[i].perms, mask);
+ mask = state->groups->aces[i].perms.deny;
+ deny_bits(&state->owner, mask);
+ deny_bits(&state->group, mask);
+ deny_bits(&state->everyone, mask);
+ deny_bits_array(state->users, mask);
+ deny_bits_array(state->groups, mask);
+ }
+ break;
+ case ACL_OTHER:
+ if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) {
+ allow_bits(&state->owner, mask);
+ allow_bits(&state->group, mask);
+ allow_bits(&state->other, mask);
+ allow_bits(&state->everyone, mask);
+ allow_bits_array(state->users, mask);
+ allow_bits_array(state->groups, mask);
+ } else {
+ deny_bits(&state->owner, mask);
+ deny_bits(&state->group, mask);
+ deny_bits(&state->other, mask);
+ deny_bits(&state->everyone, mask);
+ deny_bits_array(state->users, mask);
+ deny_bits_array(state->groups, mask);
+ }
+ }
+}
+
+static int nfs4_acl_nfsv4_to_posix(struct nfs4_acl *acl,
+ struct posix_acl **pacl, struct posix_acl **dpacl,
+ unsigned int flags)
+{
+ struct posix_acl_state effective_acl_state, default_acl_state;
+ struct nfs4_ace *ace;
+ int ret;
+
+ ret = init_state(&effective_acl_state, acl->naces);
+ if (ret)
+ return ret;
+ ret = init_state(&default_acl_state, acl->naces);
+ if (ret)
+ goto out_estate;
+ ret = -EINVAL;
+ for (ace = acl->aces; ace < acl->aces + acl->naces; ace++) {
+ if (ace->type != NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE &&
+ ace->type != NFS4_ACE_ACCESS_DENIED_ACE_TYPE)
+ goto out_dstate;
+ if (ace->flag & ~NFS4_SUPPORTED_FLAGS)
+ goto out_dstate;
+ if ((ace->flag & NFS4_INHERITANCE_FLAGS) == 0) {
+ process_one_v4_ace(&effective_acl_state, ace);
+ continue;
+ }
+ if (!(flags & NFS4_ACL_DIR))
+ goto out_dstate;
+ /*
+ * Note that when only one of FILE_INHERIT or DIRECTORY_INHERIT
+ * is set, we're effectively turning on the other. That's OK,
+ * according to rfc 3530.
+ */
+ process_one_v4_ace(&default_acl_state, ace);
+
+ if (!(ace->flag & NFS4_ACE_INHERIT_ONLY_ACE))
+ process_one_v4_ace(&effective_acl_state, ace);
+ }
+
+ /*
+ * At this point, the default ACL may have zeroed-out entries for owner,
+ * group and other. That usually results in a non-sensical resulting ACL
+ * that denies all access except to any ACE that was explicitly added.
+ *
+ * The setfacl command solves a similar problem with this logic:
+ *
+ * "If a Default ACL entry is created, and the Default ACL contains
+ * no owner, owning group, or others entry, a copy of the ACL
+ * owner, owning group, or others entry is added to the Default ACL."
+ *
+ * Copy any missing ACEs from the effective set, if any ACEs were
+ * explicitly set.
+ */
+ if (default_acl_state.valid) {
+ if (!(default_acl_state.valid & ACL_USER_OBJ))
+ default_acl_state.owner = effective_acl_state.owner;
+ if (!(default_acl_state.valid & ACL_GROUP_OBJ))
+ default_acl_state.group = effective_acl_state.group;
+ if (!(default_acl_state.valid & ACL_OTHER))
+ default_acl_state.other = effective_acl_state.other;
+ }
+
+ *pacl = posix_state_to_acl(&effective_acl_state, flags);
+ if (IS_ERR(*pacl)) {
+ ret = PTR_ERR(*pacl);
+ *pacl = NULL;
+ goto out_dstate;
+ }
+ *dpacl = posix_state_to_acl(&default_acl_state,
+ flags | NFS4_ACL_TYPE_DEFAULT);
+ if (IS_ERR(*dpacl)) {
+ ret = PTR_ERR(*dpacl);
+ *dpacl = NULL;
+ posix_acl_release(*pacl);
+ *pacl = NULL;
+ goto out_dstate;
+ }
+ sort_pacl(*pacl);
+ sort_pacl(*dpacl);
+ ret = 0;
+out_dstate:
+ free_state(&default_acl_state);
+out_estate:
+ free_state(&effective_acl_state);
+ return ret;
+}
+
+__be32 nfsd4_acl_to_attr(enum nfs_ftype4 type, struct nfs4_acl *acl,
+ struct nfsd_attrs *attr)
+{
+ int host_error;
+ unsigned int flags = 0;
+
+ if (!acl)
+ return nfs_ok;
+
+ if (type == NF4DIR)
+ flags = NFS4_ACL_DIR;
+
+ host_error = nfs4_acl_nfsv4_to_posix(acl, &attr->na_pacl,
+ &attr->na_dpacl, flags);
+ if (host_error == -EINVAL)
+ return nfserr_attrnotsupp;
+ else
+ return nfserrno(host_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;
+}
+
+/*
+ * return the size of the struct nfs4_acl required to represent an acl
+ * with @entries entries.
+ */
+int nfs4_acl_bytes(int entries)
+{
+ return sizeof(struct nfs4_acl) + entries * sizeof(struct nfs4_ace);
+}
+
+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;
+}
+
+__be32 nfs4_acl_write_who(struct xdr_stream *xdr, int who)
+{
+ __be32 *p;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(s2t_map); i++) {
+ if (s2t_map[i].type != who)
+ continue;
+ p = xdr_reserve_space(xdr, s2t_map[i].stringlen + 4);
+ if (!p)
+ return nfserr_resource;
+ p = xdr_encode_opaque(p, s2t_map[i].string,
+ s2t_map[i].stringlen);
+ return 0;
+ }
+ WARN_ON_ONCE(1);
+ return nfserr_serverfault;
+}