source: fedd/abac-src/ttg/trust/LinkTTNode.java @ 012dba5

package com.nailabs.abac.trust;

import com.nailabs.abac.process.*;
import edu.stanford.peer.rbtm.credential.*;
import java.util.*;

/**
 * This is a specialized standard trust target which knows how to process 
 * linked trust targets. 
 */
public class LinkTTNode extends StandardTTNode {
    private LinkingGoal monitorId = null;

    /** default constructor for standard trust target node */
    public LinkTTNode(TrustTarget target) {
        super(target);
        processor = new ProcessingState(false, false);
        subName = "LinkedTarget";
    }

    public Role getFirstRole() {
        LinkedRole role = (LinkedRole)getTargetExpression();
        return role.getFirstRole();
    }

    public RoleName getSecondRoleName() {
        LinkedRole role = (LinkedRole)getTargetExpression();
        return role.getSecondRoleName();
    }

    protected void _process(NegotiationContext context) {
        TTG graph = context.getGraph();

        if(monitorId == null) {
            try {
                Entity v = getVerifier();
                EntityExpression s = getSubject();
                monitorId = new LinkingGoal(v, getSecondRoleName(), s);
            } catch (Exception ex) {
                // add a warning message here--something has gone very wrong
                return;
            }
        }
        // 1. Add the (unique( linking-monitor edge, T <--< <V: ?X.r2 <<-?- S>
        if(!children.containsKey(monitorId)) {
            graph.addLinkingMonitorEdge((TrustTarget)getGoal(), monitorId);
        }

        // 
        // This happens when the LinkingGoalNode is processed. It doesn't
        // actually happen here.
        //
        // 2. After (1) is done, V can add a linking implication edge 
        //    T <--< <V: A.r1 <<-?- B> for each linking-solution edge
        //    <V: ?X.r2 <<-?- S> <--< <V: B.r2 <<-?- S> such that each
        //    grandchild (<V: B.r2 <<-?- S>) is satisfied.
        //

    }
    
    /** 
     * Process a node whose trust target verifier entity is not self 
     * @see RMINegotiator
     */
    public void opponentProcess(NegotiationContext context) {
        TTG graph = context.getGraph();
        Entity v = getVerifier();
        EntityExpression s = getSubject();

        //Initialize the unique id for the linking monitor child linking goal
        if(monitorId == null) {
            try {
                monitorId = new LinkingGoal(v, getSecondRoleName(), s);
            } catch (Exception ex) {
                // add a warning message here--something has gone very wrong
                return;
            }
        }
        // 1. Add the (unique( linking-monitor edge, T <--< <V: ?X.r2 <<-?- S>
        if(!children.containsKey(monitorId)) {
            graph.addLinkingMonitorEdge((TrustTarget)getGoal(), monitorId);
        }

        // 
        // This happens when the LinkingGoalNode is processed. It doesn't
        // actually happen here.
        //
        // 2. After (1) is done, V can add a linking implication edge 
        //    T <--< <V: A.r1 <<-?- B> for each linking-solution edge
        //    <V: ?X.r2 <<-?- S> <--< <V: B.r2 <<-?- S> such that each
        //    grandchild (<V: B.r2 <<-?- S>) is satisfied.
        //

        LinkingGoalNode childNode = 
            (LinkingGoalNode)graph.getNodeByHash(monitorId);
        _process(context);
        // 3. Mark this node verifier processed only after both 1 & 2 
        // are done and <V: ?X.r2 <<-?- S> has a complete completion state.
        if(childNode.getProcessingState().isOpponentProcessed()
           && childNode.isComplete()) {
            graph.setOpponentProcessed(getGoal());
        }
    }


    /** 
     * Process a node whose trust target verifier entity is self 
     * @see RMINegotiator
     */
    public void verifierProcess(NegotiationContext context) {
        FrontierManager fm = context.getFrontier();
        TTG graph = context.getGraph();
        RoleName r1 = getFirstRole().getName();

        //
        // If r1 is issuer-traces-def
        //
        if(fm.isIssuerTracesDef(r1)) {
            if(monitorId == null) {
                try {
                    Entity v = getVerifier();
                    EntityExpression s = getSubject();
                    monitorId = new LinkingGoal(v, getSecondRoleName(), s);
                } catch (Exception ex) {
                    // add a warning message here
                    // something has gone very wrong!!
                    return;
                }
            }
            // 1. Add the (unique) linking-monitor edge, 
            //    T <--< <V: ?X.r2 <<-?- S>
            if(!children.containsKey(monitorId)) {
                graph.addLinkingMonitorEdge((TrustTarget)getGoal(), monitorId);
            }
            
            // 
            // This happens when the LinkingGoalNode is processed. It doesn't
            // actually happen here.
            //
            // 2. After (1) is done, V can add a linking implication edge 
            //    T <--< <V: A.r1 <<-?- B> for each linking-solution edge
            //    <V: ?X.r2 <<-?- S> <--< <V: B.r2 <<-?- S> such that each
            //    grandchild (<V: B.r2 <<-?- S>) is satisfied.
            //

            // 3. Mark this node verifier processed only after both 1 & 2 
            // are done and <V: ?X.r2 <<-?- S> has a complete completion state.
            LinkingGoalNode childNode = 
                (LinkingGoalNode)graph.getNodeByHash(monitorId);
            if(childNode.getProcessingState().isVerifierProcessed()
               && childNode.isComplete()) {
                   graph.setVerifierProcessed(getGoal());
            }
        }
        //
        // If r1 is issuer-traces-all
        //
        if(fm.isIssuerTracesAll(r1)) {
            // 1. For each entity B such that A.r1 <<-?- B, and for each e
            //    such that e is an element of oppoFrontier(B.r2), V can add a
            //    standard implication edge T,--< <V: e <<-?- S>
            Iterator i = 
                fm.getOppoLocal(getFirstRole()).resultSet().iterator();
            while(i.hasNext()) {
                EntityExpression expr=(EntityExpression)i.next();
                //debug("linked", "issuer-traces-all matched " + cred);
                try {
                    if(expr instanceof Entity) { 
                        Entity b = (Entity)expr;
                        Role bDotR2 = new Role(b, getSecondRoleName());
                        Iterator oppoSet = 
                            fm.getOppoFrontier(bDotR2).resultSet().iterator();
                        while(oppoSet.hasNext()) {
                            EntityExpression e = (EntityExpression)oppoSet.next();
                            TrustTarget child = new 
                                TrustTarget(getVerifier(), e, getSubject());
                            //get evidence here
                            graph.addImplicationEdge(getGoal(), child, null);
                        }   
                    }
                } catch (Exception ex) {
                    ex.printStackTrace();
                }

            }
            // 2. V can mark T as verifier-processed only after step 1 is done
            graph.setVerifierProcessed(getGoal());
        }
    }

    /** 
     * A comparator function to see if the specified role matches the second 
     * role name.
     */
    protected boolean isLinkingSolution(Role r) {
        RoleName r2 = getSecondRoleName();
        
        return (r2.equals(r.getName()));
    }

    /**
     * When the linking child monitor becomes complete, this node needs to
     * change it's processing state.
     * @param state The new satisfaction state to be propagated. 
     */
    public void receive(LinkingGoal source, CompletionState state) {
        TTG graph = getContext().getGraph();
        FrontierManager fm = getContext().getFrontier();
        Entity me = fm.getSelf();
        RoleName r1 = getFirstRole().getName();
        boolean subjectTraceable = fm.isSubjectTraceable(r1);
        
        if(state.isComplete() && source.equals(monitorId)) {
            if(me.equals(getVerifier())) {
                if(!subjectTraceable) {
                    //if r1 is not subject traceable
                    graph.setVerifierProcessed(getGoal());
                }
            } else {
                if(subjectTraceable) {
                    //if r1 is subject traceable 
                    graph.setOpponentProcessed(getGoal());
                }
            }
        }
    }
}