EndGame v3

sourcecode/gobalance/pkg/onionbalance/torNode.go

@@ -0,0 +1,113 @@
+package onionbalance
+
+import (
+	"encoding/base64"
+	"encoding/binary"
+	"errors"
+	"github.com/sirupsen/logrus"
+	"golang.org/x/crypto/sha3"
+	"strings"
+	"sync"
+)
+
+type TorNode struct {
+	microdescriptor    MicroDescriptor
+	microdescriptorMtx sync.RWMutex
+	routerstatus       *RouterStatus
+	routerstatusMtx    sync.RWMutex
+}
+
+func NewNode(microdescriptor MicroDescriptor, routerstatus *RouterStatus) *TorNode {
+	logrus.Debugf("Initializing node with fpr %s", routerstatus.Fingerprint)
+
+	n := &TorNode{}
+	n.setMicrodescriptor(microdescriptor)
+	n.setRouterstatus(routerstatus)
+	return n
+}
+
+func (n *TorNode) getRouterstatus() *RouterStatus {
+	n.routerstatusMtx.RLock()
+	defer n.routerstatusMtx.RUnlock()
+	return n.routerstatus
+}
+
+func (n *TorNode) setRouterstatus(newVal *RouterStatus) {
+	n.routerstatusMtx.Lock()
+	defer n.routerstatusMtx.Unlock()
+	n.routerstatus = newVal
+}
+
+func (n *TorNode) getMicrodescriptor() MicroDescriptor {
+	n.microdescriptorMtx.RLock()
+	defer n.microdescriptorMtx.RUnlock()
+	return n.microdescriptor
+}
+
+func (n *TorNode) setMicrodescriptor(newVal MicroDescriptor) {
+	n.microdescriptorMtx.Lock()
+	defer n.microdescriptorMtx.Unlock()
+	n.microdescriptor = newVal
+}
+
+func (n *TorNode) GetHexFingerprint() Fingerprint {
+	return n.getRouterstatus().Fingerprint
+}
+
+var ErrNoHSDir = errors.New("NoHSDir")
+var ErrNoEd25519Identity = errors.New("NoEd25519Identity")
+
+// GetHsdirIndex get the HSDir index for this node:
+//
+//    hsdir_index(node) = H("node-idx" | node_identity |
+//                          shared_random_value |
+//                          INT_8(period_num) |
+//                          INT_8(period_length) )
+//
+// Raises NoHSDir or NoEd25519Identity in case of errors.
+func (n *TorNode) GetHsdirIndex(srv []byte, period_num int64, consensus *Consensus) ([]byte, error) {
+	// See if this node can be an HSDir (it needs to be supported both in
+	// protover and in flags)
+	//arr, found := n.routerstatus.Protocols["HSDir"]
+	//if !found {
+	//	panic("NoHSDir")
+	//}
+	//found = false
+	//for _, el := range arr {
+	//	if 2 == el {
+	//		found = true
+	//		break
+	//	}
+	//}
+	//if !found {
+	//	panic("NoHSDir")
+	//}
+	if !n.getRouterstatus().Flags.HSDir {
+		return nil, ErrNoHSDir
+	}
+
+	// See if ed25519 identity is supported for this node
+	if _, found := n.getMicrodescriptor().Identifiers["ed25519"]; !found {
+		return nil, ErrNoEd25519Identity
+	}
+
+	// In stem the ed25519 identity is a base64 string and we need to add
+	// the missing padding so that the python base64 module can successfully
+	// decode it.
+	// TODO: Abstract this into its own function...
+	ed25519NodeIdentityB64 := n.getMicrodescriptor().Identifiers["ed25519"]
+	missingPadding := len(ed25519NodeIdentityB64) % 4
+	ed25519NodeIdentityB64 += strings.Repeat("=", missingPadding)
+	ed25519NodeIdentity, _ := base64.StdEncoding.DecodeString(ed25519NodeIdentityB64)
+
+	periodNumInt8 := make([]byte, 8)
+	binary.BigEndian.PutUint64(periodNumInt8[len(periodNumInt8)-8:], uint64(period_num))
+	periodLength := consensus.Consensus().GetTimePeriodLength()
+	periodLengthInt8 := make([]byte, 8)
+	binary.BigEndian.PutUint64(periodLengthInt8[len(periodLengthInt8)-8:], uint64(periodLength))
+
+	hashBody := "node-idx" + string(ed25519NodeIdentity) + string(srv) + string(periodNumInt8) + string(periodLengthInt8)
+	hsdirIndex := sha3.Sum256([]byte(hashBody))
+
+	return hsdirIndex[:], nil
+}