Exemplo n.º 1
0
// ProposeVote calls the 'accept'-vote on the current propose-configuration
func (i *Identity) ProposeVote(accept bool) onet.ClientError {
	log.Lvl3("Voting proposal")
	if i.Proposed == nil {
		return onet.NewClientErrorCode(ErrorConfigMissing, "No proposed config")
	}
	log.Lvlf3("Voting %t on %s", accept, i.Proposed.Device)
	if !accept {
		return nil
	}
	hash, err := i.Proposed.Hash()
	if err != nil {
		return onet.NewClientErrorCode(ErrorOnet, err.Error())
	}
	sig, err := crypto.SignSchnorr(network.Suite, i.Private, hash)
	if err != nil {
		return onet.NewClientErrorCode(ErrorOnet, err.Error())
	}
	pvr := &ProposeVoteReply{}
	cerr := i.Client.SendProtobuf(i.Cothority.RandomServerIdentity(), &ProposeVote{
		ID:        i.ID,
		Signer:    i.DeviceName,
		Signature: &sig,
	}, pvr)
	if cerr != nil {
		return cerr
	}
	if pvr.Data != nil {
		log.Lvl2("Threshold reached and signed")
		i.Config = i.Proposed
		i.Proposed = nil
	} else {
		log.Lvl2("Threshold not reached")
	}
	return nil
}
Exemplo n.º 2
0
// CreateIdentity will register a new SkipChain and add it to our list of
// managed identities.
func (s *Service) CreateIdentity(ai *CreateIdentity) (network.Body, onet.ClientError) {
	log.Lvlf3("%s Creating new identity with config %+v", s, ai.Config)
	ids := &Storage{
		Latest: ai.Config,
	}
	log.Lvl3("Creating Root-skipchain")
	var cerr onet.ClientError
	ids.Root, cerr = s.skipchain.CreateRoster(ai.Roster, 2, 10,
		skipchain.VerifyNone, nil)
	if cerr != nil {
		return nil, cerr
	}
	log.Lvl3("Creating Data-skipchain")
	ids.Root, ids.Data, cerr = s.skipchain.CreateData(ids.Root, 2, 10,
		skipchain.VerifyNone, ai.Config)
	if cerr != nil {
		return nil, cerr
	}

	roster := ids.Root.Roster
	replies, err := s.propagateIdentity(roster, &PropagateIdentity{ids}, propagateTimeout)
	if err != nil {
		return nil, onet.NewClientErrorCode(ErrorOnet, err.Error())
	}
	if replies != len(roster.List) {
		log.Warn("Did only get", replies, "out of", len(roster.List))
	}
	log.Lvlf2("New chain is\n%x", []byte(ids.Data.Hash))
	s.save()

	return &CreateIdentityReply{
		Root: ids.Root,
		Data: ids.Data,
	}, nil
}
Exemplo n.º 3
0
// StartChallenge starts the challenge phase. Typically called by the Root ;)
func (c *CoSi) startChallenge() error {
	challenge, err := c.cosi.CreateChallenge(c.Message)
	if err != nil {
		return err
	}
	out := &Challenge{
		Chall: challenge,
	}
	log.Lvlf3("%s Starting Chal=%+v (message = %x)", c.Name(), challenge, c.Message)
	return c.handleChallenge(out)

}
Exemplo n.º 4
0
// PropagateSkipBlock will save a new SkipBlock
func (s *Service) PropagateSkipBlock(msg network.Body) {
	sb, ok := msg.(*SkipBlock)
	if !ok {
		log.Error("Couldn't convert to SkipBlock")
		return
	}
	if err := sb.VerifySignatures(); err != nil {
		log.Error(err)
		return
	}
	s.storeSkipBlock(sb)
	log.Lvlf3("Stored skip block %+v in %x", *sb, s.Context.ServerIdentity().ID[0:8])
}
Exemplo n.º 5
0
// handleAnnouncement will pass the message to the round and send back the
// output. If in == nil, we are root and we start the round.
func (c *CoSi) handleAnnouncement(in *Announcement) error {
	log.Lvlf3("Message: %x", c.Message)
	// If we have a hook on announcement call the hook
	if c.announcementHook != nil {
		return c.announcementHook()
	}

	// If we are leaf, we should go to commitment
	if c.IsLeaf() {
		return c.handleCommitment(nil)
	}
	// send to children
	return c.SendToChildren(in)
}
Exemplo n.º 6
0
// handleChallenge dispatch the challenge to the round and then dispatch the
// results down the tree.
func (c *CoSi) handleChallenge(in *Challenge) error {
	log.Lvlf3("%s chal=%+v", c.Name(), in.Chall)
	c.cosi.Challenge(in.Chall)

	if c.challengeHook != nil {
		c.challengeHook(in.Chall)
	}

	// if we are leaf, then go to response
	if c.IsLeaf() {
		return c.handleResponse(nil)
	}

	// otherwise send it to children
	return c.SendToChildren(in)
}
Exemplo n.º 7
0
// notify other services about new/updated skipblock
func (s *Service) startPropagation(blocks []*SkipBlock) onet.ClientError {
	log.Lvlf3("Starting to propagate for service %x", s.Context.ServerIdentity().ID[0:8])
	for _, block := range blocks {
		roster := block.Roster
		if roster == nil {
			// Suppose it's a dataSkipBlock
			sb, ok := s.getSkipBlockByID(block.ParentBlockID)
			if !ok {
				return onet.NewClientErrorCode(ErrorBlockNoParent, "Didn't find Roster nor parent")
			}
			roster = sb.Roster
		}
		replies, e := s.Propagate(roster, block, propagateTimeout)
		if e != nil {
			return onet.NewClientErrorCode(ErrorOnet, e.Error())
		}
		if replies != len(roster.List) {
			log.Warn("Did only get", replies, "out of", len(roster.List))
		}
	}
	return nil
}
Exemplo n.º 8
0
// handleChallengeCommit verifies the signature and checks if not more than
// the threshold of participants refused to sign
func (bft *ProtocolBFTCoSi) handleChallengeCommit(msg challengeCommitChan) error {
	if bft.isClosing() {
		return nil
	}

	ch := msg.ChallengeCommit
	if !bft.IsRoot() {
		bft.commit.Challenge(ch.Challenge)
	}

	// verify if the signature is correct
	data := sha512.Sum512(ch.Signature.Msg)
	bftPrepareSig := &BFTSignature{
		Sig:        ch.Signature.Sig,
		Msg:        data[:],
		Exceptions: ch.Signature.Exceptions,
	}
	if err := bftPrepareSig.Verify(bft.Suite(), bft.Roster().Publics()); err != nil {
		log.Lvl3(bft.Name(), "Verification of the signature failed:", err)
		bft.signRefusal = true
	}

	// Check if we have no more than threshold failed nodes
	if len(ch.Signature.Exceptions) >= int(bft.threshold) {
		log.Lvlf3("%s: More than threshold (%d/%d) refused to sign - aborting.",
			bft.Roster(), len(ch.Signature.Exceptions), len(bft.Roster().List))
		bft.signRefusal = true
	}

	// store the exceptions for later usage
	bft.tempExceptions = ch.Signature.Exceptions

	if bft.IsLeaf() {
		return bft.handleResponseCommit(nil)
	}

	return bft.SendToChildrenInParallel(&ch)
}
Exemplo n.º 9
0
// setIdentityStorage saves an IdentityStorage
func (s *Service) setIdentityStorage(id ID, is *Storage) {
	s.identitiesMutex.Lock()
	defer s.identitiesMutex.Unlock()
	log.Lvlf3("%s %x %v", s.Context.ServerIdentity(), id[0:8], is.Latest.Device)
	s.Identities[string(id)] = is
}
Exemplo n.º 10
0
func (rh *RandHound) handleR1(r1 WR1) error {

	msg := &r1.R1

	idx := r1.RosterIndex
	grp := rh.ServerIdxToGroupNum[idx]
	pos := rh.ServerIdxToGroupIdx[idx]

	rh.mutex.Lock()
	defer rh.mutex.Unlock()

	// Verify R1 message signature
	if err := verifySchnorr(rh.Suite(), rh.key[grp][pos], msg); err != nil {
		return err
	}

	// Verify that server replied to the correct I1 message
	if err := verifyMessage(rh.Suite(), rh.i1s[grp], msg.HI1); err != nil {
		return err
	}

	// Record R1 message
	rh.r1s[idx] = msg

	// Prepare data for recovery of polynomial commits and verification of shares
	n := len(msg.EncShare)
	poly := make([][]byte, n)
	index := make([]int, n)
	encShare := make([]abstract.Point, n)
	encProof := make([]ProofCore, n)
	for i := 0; i < n; i++ {
		poly[i] = msg.CommitPoly
		index[i] = msg.EncShare[i].Pos
		encShare[i] = msg.EncShare[i].Val
		encProof[i] = msg.EncShare[i].Proof
	}

	// Init PVSS and recover polynomial commits
	H, _ := rh.Suite().Point().Pick(nil, rh.Suite().Cipher(rh.sid))
	pvss := NewPVSS(rh.Suite(), H, rh.threshold[grp])
	polyCommit, err := pvss.Commits(poly, index)
	if err != nil {
		return err
	}

	// Record polynomial commits
	rh.polyCommit[idx] = polyCommit

	// Return, if we already committed to secrets previously
	if len(rh.chosenSecret) > 0 {
		return nil
	}

	// Verify encrypted shares
	good, _, err := pvss.Verify(H, rh.key[grp], polyCommit, encShare, encProof)
	if err != nil {
		return err
	}

	// Record valid encrypted shares per secret/server
	for _, g := range good {
		if _, ok := rh.secret[idx]; !ok {
			rh.secret[idx] = make([]int, 0)
		}
		rh.secret[idx] = append(rh.secret[idx], msg.EncShare[g].Target)
	}

	// Check if there is at least a threshold number of reconstructable secrets
	// in each group. If yes proceed to the next phase. Note the double-usage
	// of the threshold which is used to determine if enough valid shares for a
	// single secret are available and if enough secrets for a given group are
	// available
	goodSecret := make(map[int][]int)
	for i, group := range rh.server {
		var secret []int
		for _, server := range group {
			j := server.RosterIndex
			if share, ok := rh.secret[j]; ok && rh.threshold[i] <= len(share) {
				secret = append(secret, j)
			}
		}
		if rh.threshold[i] <= len(secret) {
			goodSecret[i] = secret
		}
	}

	// Proceed, if there are enough good secrets
	if len(goodSecret) == rh.groups {

		// Reset secret for the next phase (see handleR2)
		rh.secret = make(map[int][]int)

		// Choose secrets that contribute to collective randomness
		for i := range rh.server {

			// Randomly remove some secrets so that a threshold of secrets remains
			rand := random.Bytes(rh.Suite().Hash().Size(), random.Stream)
			prng := rh.Suite().Cipher(rand)
			secret := goodSecret[i]
			for j := 0; j < len(secret)-rh.threshold[i]; j++ {
				k := int(random.Uint32(prng) % uint32(len(secret)))
				secret = append(secret[:k], secret[k+1:]...)
			}
			rh.chosenSecret[i] = secret
		}

		log.Lvlf3("Grouping: %v", rh.group)
		log.Lvlf3("ChosenSecret: %v", rh.chosenSecret)

		// Transformation of commitments from int to uint32 to avoid protobuff errors
		var chosenSecret = make([][]uint32, len(rh.chosenSecret))
		for i := range rh.chosenSecret {
			var l []uint32
			for j := range rh.chosenSecret[i] {
				l = append(l, uint32(rh.chosenSecret[i][j]))
			}
			chosenSecret[i] = l
		}

		// Prepare a message for each server of a group and send it
		for i, group := range rh.server {
			for j, server := range group {

				// Among the good secrets chosen previously collect all valid
				// shares, proofs, and polynomial commits intended for the
				// target server
				var encShare []Share
				var polyCommit []abstract.Point
				for _, k := range rh.chosenSecret[i] {
					r1 := rh.r1s[k]
					pc := rh.polyCommit[k]
					encShare = append(encShare, r1.EncShare[j])
					polyCommit = append(polyCommit, pc[j])
				}

				i2 := &I2{
					Sig:          crypto.SchnorrSig{},
					SID:          rh.sid,
					ChosenSecret: chosenSecret,
					EncShare:     encShare,
					PolyCommit:   polyCommit,
				}

				if err := signSchnorr(rh.Suite(), rh.Private(), i2); err != nil {
					return err
				}

				rh.i2s[server.RosterIndex] = i2

				if err := rh.SendTo(server, i2); err != nil {
					return err
				}
			}
		}
	}

	return nil
}