internal bool CheckDemandInternal(CodeAccessPermission demand, out Exception exception)
{
BCLDebug.Assert(m_head != null, "m_head != null");
for (PListNode pnext = m_head; pnext != null; pnext = pnext.next)
{
if (pnext.perm == null)
{
// If this is a grant set or a permit only, then we should fail since null indicates the empty permission.
if (pnext.type == MatchChecked || pnext.type == MatchPermitOnly)
{
BCLDebug.Assert(!demand.IsSubsetOf(null), "By the time we get here, demands that are subsets of null should have been terminated");
exception = new SecurityException(String.Format(Environment.GetResourceString("Security_Generic"), demand.GetType().AssemblyQualifiedName));
return(false);
}
// If this is a deny, then we should fail since null indicates the unrestricted permission.
if (pnext.type == MatchDeny)
{
exception = new SecurityException(String.Format(Environment.GetResourceString("Security_Generic"), demand.GetType().AssemblyQualifiedName));
return(false);
}
// If this is an assert, then we should return success and terminate the stack walk since
// null indicates the unrestricted permission.
if (pnext.type == MatchAssert)
{
exception = null;
return(false);
}
// If this is anything else, then we should act confused.
// This case is unexpected.
BCLDebug.Assert(false, "This case should never happen");
exception = new InvalidOperationException(Environment.GetResourceString("InvalidOperation_InvalidState"));
return(false);
}
CodeAccessPermission cap = pnext.perm;
switch (pnext.type)
{
case MatchChecked:
case MatchPermitOnly:
if (!demand.IsSubsetOf(cap))
{
exception = new SecurityException(String.Format(Environment.GetResourceString("Security_Generic"), demand.GetType().AssemblyQualifiedName));
return(false);
}
break;
case MatchAssert:
if (demand.IsSubsetOf(cap))
{
exception = null;
return(false);
}
break;
case MatchDeny:
if (demand.Intersect(cap) != null)
{
exception = new SecurityException(String.Format(Environment.GetResourceString("Security_Generic"), demand.GetType().AssemblyQualifiedName));
return(false);
}
break;
default:
// Illegal entry
exception = new InvalidOperationException(Environment.GetResourceString("InvalidOperation_InvalidState"));
return(false);
}
}
exception = null;
return(true);
}