Esempio n. 1
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// handleAbPublish handles Authenticated Broadcast publish requests.
// It takes the request as input.
func (b Broker) handleAbPublish(pub *pb.Publication) {
	// fmt.Printf("Handle AB Publish Publication %v, Publisher %v, Broker %v.\n", pub.PublicationID, pub.PublisherID, pub.BrokerID)

	if b.forwardSent[pub.PublisherID] == nil {
		b.forwardSent[pub.PublisherID] = make(map[int64]bool)
	}

	// If this publication has not been forwarded yet
	if b.forwardSent[pub.PublisherID][pub.PublicationID] == false {

		// Update broker ID
		pub.BrokerID = b.localID

		// Forward the publication to all subscribers
		b.subscribersMutex.RLock()
		for _, subscriber := range b.subscribers {
			// Only if they are interested in the topic
			if subscriber.toCh != nil && subscriber.topics[pub.TopicID] == true {
				subscriber.toCh <- *pub
				if len(subscriber.toCh) > b.toSubscriberChLen/2 {
					b.setBusy()
				}
			}
		}
		b.subscribersMutex.RUnlock()

		// Mark this publication as sent
		b.forwardSent[pub.PublisherID][pub.PublicationID] = true

		// For performance testing, get the time of the last step for this broker
		b.incrementPublicationCount(pub)
	} else {
		// fmt.Printf("Already forwarded publication %v by publisher %v\n", pub.PublicationID, pub.PublisherID)
	}
}
Esempio n. 2
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// handleBrbPublish handles Bracha's Reliable Broadcast publish requests.
// It takes the request as input.
func (b Broker) handleBrbPublish(pub *pb.Publication) {
	// fmt.Printf("Handle BRB Publish Publication %v, Publisher %v, Broker %v.\n", pub.PublicationID, pub.PublisherID, pub.BrokerID)

	if b.echoesSent[pub.PublisherID] == nil {
		b.echoesSent[pub.PublisherID] = make(map[int64]bool)
	}

	// If this publication has not been echoed yet
	if b.echoesSent[pub.PublisherID][pub.PublicationID] == false {

		// Update broker ID
		pub.BrokerID = b.localID

		// "Send" the echo request to itself
		b.fromBrokerEchoCh <- *pub

		// Send the echo request to all other brokers
		b.remoteBrokersMutex.RLock()
		for _, remoteBroker := range b.remoteBrokers {
			if remoteBroker.toEchoCh != nil {
				remoteBroker.toEchoCh <- *pub
				if len(remoteBroker.toEchoCh) > b.toBrbChLen/2 {
					b.setBusy()
				}
			}
		}
		b.remoteBrokersMutex.RUnlock()

		// Mark this publication as echoed
		b.echoesSent[pub.PublisherID][pub.PublicationID] = true
		// fmt.Printf("Sent echoes for  publication %v by publisher %v\n", pub.PublicationID, pub.PublisherID)
	} else {
		// fmt.Printf("Already sent echoes for publication %v by publisher %v\n", pub.PublicationID, pub.PublisherID)
	}
}
Esempio n. 3
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// addMACsRecursive adds MACs to the chain of MACs. Some older MACs may need to be kept depending
// on the number of generations in the chain.
// It takes as input the new publication,
// the old publication,
// the current node ID string in the tree (should start with the local node's children),
// and the number of generations to add.
func (b *Broker) addMACsRecursive(pub *pb.Publication, oldPub *pb.Publication, currentStr string, generations uint64) {
	// Add any old chain MACs that add going to the child node
	for _, oldChainMAC := range oldPub.ChainMACs {
		if oldChainMAC.To == currentStr {
			pub.ChainMACs = append(pub.ChainMACs, oldChainMAC)
		}
	}

	if generations > 1 {
		// Add MACs for all the broker children
		for _, childStr := range b.chainNodes[currentStr].children {
			addMAC := true

			// Check if the subscriber is subscribed to this topic
			if strings.HasPrefix(childStr, "S") {
				childID, _ := strconv.ParseUint(childStr[1:], 10, 64)
				b.subscribersMutex.RLock()
				if b.subscribers[childID].topics[pub.TopicID] == false {
					// Don't add the MAC is the subscriber isn't interested in this topic
					addMAC = false
				}
				b.subscribersMutex.RUnlock()
			}

			if addMAC {
				chainMAC := pb.ChainMAC{
					From: b.localStr,
					To:   childStr,
					MAC:  common.CreatePublicationMAC(pub, b.chainNodes[childStr].key),
				}

				pub.ChainMACs = append(pub.ChainMACs, &chainMAC)

				// Recursively add child macs for next generation
				b.addMACsRecursive(pub, oldPub, childStr, generations-1)
			}
		}
	}
}
Esempio n. 4
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// alterPublication will maliciously alter a publications information.
// It returns true if the publication was altered.
// It takes as input the publication.
func (b *Broker) alterPublication(pub *pb.Publication) pb.Publication {
	tempPub := pb.Publication{
		PubType:       pub.PubType,
		PublisherID:   pub.PublisherID,
		PublicationID: pub.PublicationID,
		TopicID:       pub.TopicID,
		BrokerID:      pub.BrokerID,
	}

	for i := range pub.Contents {
		tempPub.Contents = append(tempPub.Contents, pub.Contents[i])
	}
	for i := range pub.ChainMACs {
		tempPub.ChainMACs = append(tempPub.ChainMACs, pub.ChainMACs[i])
	}

	r := b.random.Intn(101)

	if r <= b.maliciousPercent {
		var alterType int

		if len(tempPub.ChainMACs) > 0 {
			alterType = r % 6
		} else {
			alterType = r % 5
		}
		switch alterType {
		case 0:
			tempPub.PublicationID = tempPub.PublicationID + 1
		case 1:
			tempPub.PublisherID = tempPub.PublisherID + 1
		case 2:
			tempPub.BrokerID = tempPub.BrokerID + 1
		case 3:
			tempPub.TopicID = tempPub.TopicID + 1
		case 4:
			if len(tempPub.Contents) > 0 {
				tempPub.Contents[0] = badMessage
			}
		case 5:
			tempPub.ChainMACs = nil
		}
	}

	return tempPub
}
Esempio n. 5
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// addMACsRecursive adds MACs to the chain of MACs.
// It takes as input the publication,
// the current node ID string in the tree (should start with the local node's children),
// and the number of generations to add.
func (p *Publisher) addMACs(pub *pb.Publication, currentStr string, generations uint64) {
	if generations > 1 {
		// Add MACs for all the children
		for _, childStr := range p.chainNodes[currentStr].children {
			chainMAC := pb.ChainMAC{
				From: p.localStr,
				To:   childStr,
				MAC:  common.CreatePublicationMAC(pub, p.chainNodes[childStr].key),
			}

			pub.ChainMACs = append(pub.ChainMACs, &chainMAC)

			// Recursively add child macs for next generation
			p.addMACs(pub, childStr, generations-1)
		}
	}
}
Esempio n. 6
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// handleEcho handles echo requests from Bracha's Reliable Broadcast.
// It takes the request as input.
func (b Broker) handleEcho(pub *pb.Publication) {
	// fmt.Printf("Handle echo Publication %v, Publisher %v, Broker %v.\n", pub.PublicationID, pub.PublisherID, pub.BrokerID)

	// Make the map so not trying to access nil reference
	if b.echoesReceived[pub.PublisherID] == nil {
		b.echoesReceived[pub.PublisherID] = make(map[int64]map[uint64]string)
	}
	// Make the map so not trying to access nil reference
	if b.echoesReceived[pub.PublisherID][pub.PublicationID] == nil {
		b.echoesReceived[pub.PublisherID][pub.PublicationID] = make(map[uint64]string)
	}
	// Echo has not been received yet for this publisher ID, publication ID, broker ID
	if b.echoesReceived[pub.PublisherID][pub.PublicationID][pub.BrokerID] == "" {
		// So record it
		b.echoesReceived[pub.PublisherID][pub.PublicationID][pub.BrokerID] = common.GetInfo(pub)

		// Check if there is a quorum yet for this publisher ID and publication ID
		foundQuorum := b.checkEchoQuorum(pub.PublisherID, pub.PublicationID)

		if b.readiesSent[pub.PublisherID] == nil {
			b.readiesSent[pub.PublisherID] = make(map[int64]bool)
		}

		// If this publication has not been readied yet
		if foundQuorum && b.readiesSent[pub.PublisherID][pub.PublicationID] == false {

			// Update broker ID
			pub.BrokerID = b.localID

			// "Send" the ready request to itself
			b.fromBrokerReadyCh <- *pub

			// Send the ready to all other brokers
			b.remoteBrokersMutex.RLock()
			for _, remoteBroker := range b.remoteBrokers {
				if remoteBroker.toReadyCh != nil {
					remoteBroker.toReadyCh <- *pub
					if len(remoteBroker.toReadyCh) > b.toBrbChLen/2 {
						b.setBusy()
					}
				}
			}
			b.remoteBrokersMutex.RUnlock()

			// Send the publication to all subscribers
			b.subscribersMutex.RLock()
			for _, subscriber := range b.subscribers {
				// Only if they are interested in the topic
				if subscriber.toCh != nil && subscriber.topics[pub.TopicID] == true {
					subscriber.toCh <- *pub
					if len(subscriber.toCh) > b.toSubscriberChLen/2 {
						b.setBusy()
					}
				}
			}
			b.subscribersMutex.RUnlock()

			// Mark this publication as readied
			b.readiesSent[pub.PublisherID][pub.PublicationID] = true
			// fmt.Printf("handleEcho: Sent readies for publication %v by publisher %v.\n", pub.PublicationID, pub.PublisherID)

			// For performance testing, get the time of the last step for this broker
			b.incrementPublicationCount(pub)
		}
	}
}