/*
* 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;
}
/*
* Convert from extended attribute to in-memory representation.
*/
struct posix_acl *
posix_acl_from_xattr(const void *value, size_t size)
{
posix_acl_xattr_header *header = (posix_acl_xattr_header *)value;
posix_acl_xattr_entry *entry = (posix_acl_xattr_entry *)(header+1), *end;
int count;
struct posix_acl *acl;
struct posix_acl_entry *acl_e;
if (!value)
return NULL;
if (size < sizeof(posix_acl_xattr_header))
return ERR_PTR(-EINVAL);
if (header->a_version != cpu_to_le32(POSIX_ACL_XATTR_VERSION))
return ERR_PTR(-EOPNOTSUPP);
count = posix_acl_xattr_count(size);
if (count < 0)
return ERR_PTR(-EINVAL);
if (count == 0)
return NULL;
acl = posix_acl_alloc(count, GFP_NOFS);
if (!acl)
return ERR_PTR(-ENOMEM);
acl_e = acl->a_entries;
for (end = entry + count; entry != end; acl_e++, entry++) {
acl_e->e_tag = le16_to_cpu(entry->e_tag);
acl_e->e_perm = le16_to_cpu(entry->e_perm);
switch(acl_e->e_tag) {
case ACL_USER_OBJ:
case ACL_GROUP_OBJ:
case ACL_MASK:
case ACL_OTHER:
acl_e->e_id = ACL_UNDEFINED_ID;
break;
case ACL_USER:
case ACL_GROUP:
acl_e->e_id = le32_to_cpu(entry->e_id);
break;
default:
goto fail;
}
}
return acl;
fail:
posix_acl_release(acl);
return ERR_PTR(-EINVAL);
}
/*
* Fix up the uids and gids in posix acl extended attributes in place.
*/
static void posix_acl_fix_xattr_userns(
struct user_namespace *to, struct user_namespace *from,
void *value, size_t size)
{
posix_acl_xattr_header *header = (posix_acl_xattr_header *)value;
posix_acl_xattr_entry *entry = (posix_acl_xattr_entry *)(header+1), *end;
int count;
kuid_t uid;
kgid_t gid;
if (!value)
return;
if (size < sizeof(posix_acl_xattr_header))
return;
if (header->a_version != cpu_to_le32(POSIX_ACL_XATTR_VERSION))
return;
count = posix_acl_xattr_count(size);
if (count < 0)
return;
if (count == 0)
return;
for (end = entry + count; entry != end; entry++) {
switch(le16_to_cpu(entry->e_tag)) {
case ACL_USER:
uid = make_kuid(from, le32_to_cpu(entry->e_id));
entry->e_id = cpu_to_le32(from_kuid(to, uid));
break;
case ACL_GROUP:
gid = make_kgid(from, le32_to_cpu(entry->e_id));
entry->e_id = cpu_to_le32(from_kuid(to, uid));
break;
default:
break;
}
}
}
