/// <summary>
/// If a default ACL is defined on a parent directory, then copies that default
/// ACL to a newly created child file or directory.
/// </summary>
/// <param name="child">INode newly created child</param>
public static void CopyINodeDefaultAcl(INode child)
{
INodeDirectory parent = child.GetParent();
AclFeature parentAclFeature = parent.GetAclFeature();
if (parentAclFeature == null || !(child.IsFile() || child.IsDirectory()))
{
return;
}
// Split parent's entries into access vs. default.
IList <AclEntry> featureEntries = GetEntriesFromAclFeature(parent.GetAclFeature());
ScopedAclEntries scopedEntries = new ScopedAclEntries(featureEntries);
IList <AclEntry> parentDefaultEntries = scopedEntries.GetDefaultEntries();
// The parent may have an access ACL but no default ACL. If so, exit.
if (parentDefaultEntries.IsEmpty())
{
return;
}
// Pre-allocate list size for access entries to copy from parent.
IList <AclEntry> accessEntries = Lists.NewArrayListWithCapacity(parentDefaultEntries
.Count);
FsPermission childPerm = child.GetFsPermission();
// Copy each default ACL entry from parent to new child's access ACL.
bool parentDefaultIsMinimal = AclUtil.IsMinimalAcl(parentDefaultEntries);
foreach (AclEntry entry in parentDefaultEntries)
{
AclEntryType type = entry.GetType();
string name = entry.GetName();
AclEntry.Builder builder = new AclEntry.Builder().SetScope(AclEntryScope.Access).
SetType(type).SetName(name);
// The child's initial permission bits are treated as the mode parameter,
// which can filter copied permission values for owner, mask and other.
FsAction permission;
if (type == AclEntryType.User && name == null)
{
permission = entry.GetPermission().And(childPerm.GetUserAction());
}
else
{
if (type == AclEntryType.Group && parentDefaultIsMinimal)
{
// This only happens if the default ACL is a minimal ACL: exactly 3
// entries corresponding to owner, group and other. In this case,
// filter the group permissions.
permission = entry.GetPermission().And(childPerm.GetGroupAction());
}
else
{
if (type == AclEntryType.Mask)
{
// Group bits from mode parameter filter permission of mask entry.
permission = entry.GetPermission().And(childPerm.GetGroupAction());
}
else
{
if (type == AclEntryType.Other)
{
permission = entry.GetPermission().And(childPerm.GetOtherAction());
}
else
{
permission = entry.GetPermission();
}
}
}
}
builder.SetPermission(permission);
accessEntries.AddItem(builder.Build());
}
// A new directory also receives a copy of the parent's default ACL.
IList <AclEntry> defaultEntries = child.IsDirectory() ? parentDefaultEntries : Sharpen.Collections
.EmptyList <AclEntry>();
FsPermission newPerm;
if (!AclUtil.IsMinimalAcl(accessEntries) || !defaultEntries.IsEmpty())
{
// Save the new ACL to the child.
child.AddAclFeature(CreateAclFeature(accessEntries, defaultEntries));
newPerm = CreateFsPermissionForExtendedAcl(accessEntries, childPerm);
}
else
{
// The child is receiving a minimal ACL.
newPerm = CreateFsPermissionForMinimalAcl(accessEntries, childPerm);
}
child.SetPermission(newPerm);
}