p2p: make encryption handshake code easier to follow
This mostly changes how information is passed around. Instead of using many function parameters and return values, put the entire state in a struct and pass that. This also adds back derivation of ecdhe-shared-secret. I deleted it by accident in a previous refactoring.
This commit is contained in:
Felix Lange
parent
2c505efd1e
commit
7d39fd6678
455
p2p/handshake.go
455
p2p/handshake.go
@ -2,6 +2,7 @@ package p2p
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import (
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"crypto/ecdsa"
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"crypto/elliptic"
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"crypto/rand"
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"errors"
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"fmt"
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@ -27,25 +28,25 @@ const (
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authRespLen = pubLen + shaLen + 1
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eciesBytes = 65 + 16 + 32
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iHSLen = authMsgLen + eciesBytes // size of the final ECIES payload sent as initiator's handshake
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rHSLen = authRespLen + eciesBytes // size of the final ECIES payload sent as receiver's handshake
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encAuthMsgLen = authMsgLen + eciesBytes // size of the final ECIES payload sent as initiator's handshake
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encAuthRespLen = authRespLen + eciesBytes // size of the final ECIES payload sent as receiver's handshake
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)
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// conn represents a remote connection after encryption handshake
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// and protocol handshake have completed.
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//
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// The MsgReadWriter is usually layered as follows:
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//
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// lockedRW (thread-safety for ReadMsg, WriteMsg)
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// rlpxFrameRW (message encoding, encryption, authentication)
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// bufio.ReadWriter (buffering)
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// net.Conn (network I/O)
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//
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type conn struct {
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MsgReadWriter
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*protoHandshake
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}
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// encHandshake contains the state of the encryption handshake.
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type encHandshake struct {
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remoteID discover.NodeID
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initiator bool
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initNonce, respNonce []byte
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dhSharedSecret []byte
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randomPrivKey *ecdsa.PrivateKey
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remoteRandomPub *ecdsa.PublicKey
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}
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// secrets represents the connection secrets
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// which are negotiated during the encryption handshake.
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type secrets struct {
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@ -64,34 +65,6 @@ type protoHandshake struct {
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ID discover.NodeID
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}
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// secrets is called after the handshake is completed.
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// It extracts the connection secrets from the handshake values.
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func (h *encHandshake) secrets(auth, authResp []byte) secrets {
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sharedSecret := crypto.Sha3(h.dhSharedSecret, crypto.Sha3(h.respNonce, h.initNonce))
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aesSecret := crypto.Sha3(h.dhSharedSecret, sharedSecret)
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s := secrets{
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RemoteID: h.remoteID,
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AES: aesSecret,
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MAC: crypto.Sha3(h.dhSharedSecret, aesSecret),
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Token: crypto.Sha3(sharedSecret),
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}
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// setup sha3 instances for the MACs
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mac1 := sha3.NewKeccak256()
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mac1.Write(xor(s.MAC, h.respNonce))
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mac1.Write(auth)
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mac2 := sha3.NewKeccak256()
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mac2.Write(xor(s.MAC, h.initNonce))
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mac2.Write(authResp)
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if h.initiator {
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s.EgressMAC, s.IngressMAC = mac1, mac2
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} else {
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s.EgressMAC, s.IngressMAC = mac2, mac1
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}
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return s
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}
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// setupConn starts a protocol session on the given connection.
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// It runs the encryption handshake and the protocol handshake.
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// If dial is non-nil, the connection the local node is the initiator.
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@ -104,7 +77,7 @@ func setupConn(fd net.Conn, prv *ecdsa.PrivateKey, our *protoHandshake, dial *di
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}
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func setupInboundConn(fd net.Conn, prv *ecdsa.PrivateKey, our *protoHandshake) (*conn, error) {
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secrets, err := inboundEncHandshake(fd, prv, nil)
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secrets, err := receiverEncHandshake(fd, prv, nil)
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if err != nil {
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return nil, fmt.Errorf("encryption handshake failed: %v", err)
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}
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@ -124,7 +97,7 @@ func setupInboundConn(fd net.Conn, prv *ecdsa.PrivateKey, our *protoHandshake) (
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}
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func setupOutboundConn(fd net.Conn, prv *ecdsa.PrivateKey, our *protoHandshake, dial *discover.Node) (*conn, error) {
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secrets, err := outboundEncHandshake(fd, prv, dial.ID[:], nil)
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secrets, err := initiatorEncHandshake(fd, prv, dial.ID, nil)
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if err != nil {
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return nil, fmt.Errorf("encryption handshake failed: %v", err)
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}
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@ -145,14 +118,66 @@ func setupOutboundConn(fd net.Conn, prv *ecdsa.PrivateKey, our *protoHandshake,
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return &conn{&lockedRW{wrapped: rw}, rhs}, nil
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}
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// outboundEncHandshake negotiates a session token on conn.
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// encHandshake contains the state of the encryption handshake.
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type encHandshake struct {
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initiator bool
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remoteID discover.NodeID
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remotePub *ecies.PublicKey // remote-pubk
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initNonce, respNonce []byte // nonce
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randomPrivKey *ecies.PrivateKey // ecdhe-random
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remoteRandomPub *ecies.PublicKey // ecdhe-random-pubk
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}
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// secrets is called after the handshake is completed.
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// It extracts the connection secrets from the handshake values.
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func (h *encHandshake) secrets(auth, authResp []byte) (secrets, error) {
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ecdheSecret, err := h.randomPrivKey.GenerateShared(h.remoteRandomPub, sskLen, sskLen)
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if err != nil {
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return secrets{}, err
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}
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// derive base secrets from ephemeral key agreement
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sharedSecret := crypto.Sha3(ecdheSecret, crypto.Sha3(h.respNonce, h.initNonce))
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aesSecret := crypto.Sha3(ecdheSecret, sharedSecret)
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s := secrets{
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RemoteID: h.remoteID,
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AES: aesSecret,
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MAC: crypto.Sha3(ecdheSecret, aesSecret),
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Token: crypto.Sha3(sharedSecret),
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}
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// setup sha3 instances for the MACs
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mac1 := sha3.NewKeccak256()
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mac1.Write(xor(s.MAC, h.respNonce))
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mac1.Write(auth)
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mac2 := sha3.NewKeccak256()
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mac2.Write(xor(s.MAC, h.initNonce))
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mac2.Write(authResp)
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if h.initiator {
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s.EgressMAC, s.IngressMAC = mac1, mac2
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} else {
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s.EgressMAC, s.IngressMAC = mac2, mac1
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}
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return s, nil
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}
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func (h *encHandshake) ecdhShared(prv *ecdsa.PrivateKey) ([]byte, error) {
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return ecies.ImportECDSA(prv).GenerateShared(h.remotePub, sskLen, sskLen)
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}
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// initiatorEncHandshake negotiates a session token on conn.
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// it should be called on the dialing side of the connection.
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//
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// privateKey is the local client's private key
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// remotePublicKey is the remote peer's node ID
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// sessionToken is the token from a previous session with this node.
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func outboundEncHandshake(conn io.ReadWriter, prvKey *ecdsa.PrivateKey, remotePublicKey []byte, sessionToken []byte) (s secrets, err error) {
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auth, initNonce, randomPrivKey, err := authMsg(prvKey, remotePublicKey, sessionToken)
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// prv is the local client's private key.
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// token is the token from a previous session with this node.
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func initiatorEncHandshake(conn io.ReadWriter, prv *ecdsa.PrivateKey, remoteID discover.NodeID, token []byte) (s secrets, err error) {
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h, err := newInitiatorHandshake(remoteID)
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if err != nil {
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return s, err
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}
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auth, err := h.authMsg(prv, token)
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if err != nil {
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return s, err
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}
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@ -160,250 +185,189 @@ func outboundEncHandshake(conn io.ReadWriter, prvKey *ecdsa.PrivateKey, remotePu
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return s, err
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}
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response := make([]byte, rHSLen)
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response := make([]byte, encAuthRespLen)
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if _, err = io.ReadFull(conn, response); err != nil {
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return s, err
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}
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recNonce, remoteRandomPubKey, _, err := completeHandshake(response, prvKey)
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if err != nil {
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if err := h.decodeAuthResp(response, prv); err != nil {
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return s, err
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}
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h := &encHandshake{
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initiator: true,
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initNonce: initNonce,
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respNonce: recNonce,
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randomPrivKey: randomPrivKey,
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remoteRandomPub: remoteRandomPubKey,
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}
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copy(h.remoteID[:], remotePublicKey)
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return h.secrets(auth, response), nil
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return h.secrets(auth, response)
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}
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// authMsg creates the initiator handshake.
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// TODO: change all the names
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func authMsg(prvKey *ecdsa.PrivateKey, remotePubKeyS, sessionToken []byte) (
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auth, initNonce []byte,
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randomPrvKey *ecdsa.PrivateKey,
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err error,
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) {
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remotePubKey, err := importPublicKey(remotePubKeyS)
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if err != nil {
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return
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func newInitiatorHandshake(remoteID discover.NodeID) (*encHandshake, error) {
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// generate random initiator nonce
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n := make([]byte, shaLen)
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if _, err := rand.Read(n); err != nil {
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return nil, err
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}
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// generate random keypair to use for signing
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randpriv, err := ecies.GenerateKey(rand.Reader, crypto.S256(), nil)
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if err != nil {
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return nil, err
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}
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rpub, err := remoteID.Pubkey()
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if err != nil {
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return nil, fmt.Errorf("bad remoteID: %v", err)
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}
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h := &encHandshake{
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initiator: true,
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remoteID: remoteID,
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remotePub: ecies.ImportECDSAPublic(rpub),
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initNonce: n,
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randomPrivKey: randpriv,
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}
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return h, nil
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}
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// authMsg creates an encrypted initiator handshake message.
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func (h *encHandshake) authMsg(prv *ecdsa.PrivateKey, token []byte) ([]byte, error) {
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var tokenFlag byte
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if sessionToken == nil {
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if token == nil {
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// no session token found means we need to generate shared secret.
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// ecies shared secret is used as initial session token for new peers
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// generate shared key from prv and remote pubkey
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if sessionToken, err = ecies.ImportECDSA(prvKey).GenerateShared(ecies.ImportECDSAPublic(remotePubKey), sskLen, sskLen); err != nil {
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return
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var err error
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if token, err = h.ecdhShared(prv); err != nil {
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return nil, err
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}
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} else {
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// for known peers, we use stored token from the previous session
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tokenFlag = 0x01
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}
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//E(remote-pubk, S(ecdhe-random, sha3(ecdh-shared-secret^nonce)) || H(ecdhe-random-pubk) || pubk || nonce || 0x0)
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// E(remote-pubk, S(ecdhe-random, sha3(token^nonce)) || H(ecdhe-random-pubk) || pubk || nonce || 0x1)
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// allocate msgLen long message,
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var msg []byte = make([]byte, authMsgLen)
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initNonce = msg[authMsgLen-shaLen-1 : authMsgLen-1]
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if _, err = rand.Read(initNonce); err != nil {
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return
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}
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// create known message
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// sign known message:
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// ecdh-shared-secret^nonce for new peers
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// token^nonce for old peers
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var sharedSecret = xor(sessionToken, initNonce)
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// generate random keypair to use for signing
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if randomPrvKey, err = crypto.GenerateKey(); err != nil {
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return
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}
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// sign shared secret (message known to both parties): shared-secret
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var signature []byte
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// signature = sign(ecdhe-random, shared-secret)
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// uses secp256k1.Sign
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if signature, err = crypto.Sign(sharedSecret, randomPrvKey); err != nil {
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return
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signed := xor(token, h.initNonce)
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signature, err := crypto.Sign(signed, h.randomPrivKey.ExportECDSA())
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if err != nil {
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return nil, err
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}
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// message
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// signed-shared-secret || H(ecdhe-random-pubk) || pubk || nonce || 0x0
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copy(msg, signature) // copy signed-shared-secret
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// H(ecdhe-random-pubk)
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var randomPubKey64 []byte
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if randomPubKey64, err = exportPublicKey(&randomPrvKey.PublicKey); err != nil {
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return
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}
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var pubKey64 []byte
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if pubKey64, err = exportPublicKey(&prvKey.PublicKey); err != nil {
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return
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}
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copy(msg[sigLen:sigLen+shaLen], crypto.Sha3(randomPubKey64))
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// pubkey copied to the correct segment.
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copy(msg[sigLen+shaLen:sigLen+shaLen+pubLen], pubKey64)
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// nonce is already in the slice
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// stick tokenFlag byte to the end
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msg[authMsgLen-1] = tokenFlag
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// encode auth message
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// signature || sha3(ecdhe-random-pubk) || pubk || nonce || token-flag
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msg := make([]byte, authMsgLen)
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n := copy(msg, signature)
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n += copy(msg[n:], crypto.Sha3(exportPubkey(&h.randomPrivKey.PublicKey)))
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n += copy(msg[n:], crypto.FromECDSAPub(&prv.PublicKey)[1:])
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n += copy(msg[n:], h.initNonce)
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msg[n] = tokenFlag
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// encrypt using remote-pubk
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// auth = eciesEncrypt(remote-pubk, msg)
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if auth, err = crypto.Encrypt(remotePubKey, msg); err != nil {
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return
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}
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return
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// encrypt auth message using remote-pubk
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return ecies.Encrypt(rand.Reader, h.remotePub, msg, nil, nil)
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}
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// completeHandshake is called when the initiator receives an
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// authentication response (aka receiver handshake). It completes the
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// handshake by reading off parameters the remote peer provides needed
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// to set up the secure session.
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func completeHandshake(auth []byte, prvKey *ecdsa.PrivateKey) (
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respNonce []byte,
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remoteRandomPubKey *ecdsa.PublicKey,
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tokenFlag bool,
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err error,
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) {
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var msg []byte
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// they prove that msg is meant for me,
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// I prove I possess private key if i can read it
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if msg, err = crypto.Decrypt(prvKey, auth); err != nil {
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return
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// decodeAuthResp decode an encrypted authentication response message.
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func (h *encHandshake) decodeAuthResp(auth []byte, prv *ecdsa.PrivateKey) error {
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msg, err := crypto.Decrypt(prv, auth)
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if err != nil {
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return fmt.Errorf("could not decrypt auth response (%v)", err)
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}
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respNonce = msg[pubLen : pubLen+shaLen]
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var remoteRandomPubKeyS = msg[:pubLen]
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if remoteRandomPubKey, err = importPublicKey(remoteRandomPubKeyS); err != nil {
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return
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h.respNonce = msg[pubLen : pubLen+shaLen]
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h.remoteRandomPub, err = importPublicKey(msg[:pubLen])
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if err != nil {
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return err
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}
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if msg[authRespLen-1] == 0x01 {
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tokenFlag = true
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}
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return
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// ignore token flag for now
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return nil
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}
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// inboundEncHandshake negotiates a session token on conn.
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// receiverEncHandshake negotiates a session token on conn.
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// it should be called on the listening side of the connection.
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//
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// privateKey is the local client's private key
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// sessionToken is the token from a previous session with this node.
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func inboundEncHandshake(conn io.ReadWriter, prvKey *ecdsa.PrivateKey, sessionToken []byte) (s secrets, err error) {
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// we are listening connection. we are responders in the
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// handshake. Extract info from the authentication. The initiator
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// starts by sending us a handshake that we need to respond to. so
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// we read auth message first, then respond.
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auth := make([]byte, iHSLen)
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// prv is the local client's private key.
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// token is the token from a previous session with this node.
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func receiverEncHandshake(conn io.ReadWriter, prv *ecdsa.PrivateKey, token []byte) (s secrets, err error) {
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// read remote auth sent by initiator.
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auth := make([]byte, encAuthMsgLen)
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if _, err := io.ReadFull(conn, auth); err != nil {
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return s, err
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}
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response, recNonce, initNonce, remotePubKey, randomPrivKey, remoteRandomPubKey, err := authResp(auth, sessionToken, prvKey)
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h, err := decodeAuthMsg(prv, token, auth)
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if err != nil {
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return s, err
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}
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if _, err = conn.Write(response); err != nil {
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// send auth response
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resp, err := h.authResp(prv, token)
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if err != nil {
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return s, err
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}
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if _, err = conn.Write(resp); err != nil {
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return s, err
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}
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h := &encHandshake{
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initiator: false,
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initNonce: initNonce,
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respNonce: recNonce,
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randomPrivKey: randomPrivKey,
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remoteRandomPub: remoteRandomPubKey,
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}
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copy(h.remoteID[:], remotePubKey)
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return h.secrets(auth, response), err
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return h.secrets(auth, resp)
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}
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// authResp is called by peer if it accepted (but not
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// initiated) the connection from the remote. It is passed the initiator
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// handshake received and the session token belonging to the
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// remote initiator.
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//
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// The first return value is the authentication response (aka receiver
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// handshake) that is to be sent to the remote initiator.
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func authResp(auth, sessionToken []byte, prvKey *ecdsa.PrivateKey) (
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authResp, respNonce, initNonce, remotePubKeyS []byte,
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randomPrivKey *ecdsa.PrivateKey,
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remoteRandomPubKey *ecdsa.PublicKey,
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err error,
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) {
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// they prove that msg is meant for me,
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// I prove I possess private key if i can read it
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msg, err := crypto.Decrypt(prvKey, auth)
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if err != nil {
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return
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}
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remotePubKeyS = msg[sigLen+shaLen : sigLen+shaLen+pubLen]
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remotePubKey, _ := importPublicKey(remotePubKeyS)
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var tokenFlag byte
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if sessionToken == nil {
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// no session token found means we need to generate shared secret.
|
||||
// ecies shared secret is used as initial session token for new peers
|
||||
// generate shared key from prv and remote pubkey
|
||||
if sessionToken, err = ecies.ImportECDSA(prvKey).GenerateShared(ecies.ImportECDSAPublic(remotePubKey), sskLen, sskLen); err != nil {
|
||||
return
|
||||
}
|
||||
// tokenFlag = 0x00 // redundant
|
||||
} else {
|
||||
// for known peers, we use stored token from the previous session
|
||||
tokenFlag = 0x01
|
||||
}
|
||||
|
||||
// the initiator nonce is read off the end of the message
|
||||
initNonce = msg[authMsgLen-shaLen-1 : authMsgLen-1]
|
||||
// I prove that i own prv key (to derive shared secret, and read
|
||||
// nonce off encrypted msg) and that I own shared secret they
|
||||
// prove they own the private key belonging to ecdhe-random-pubk
|
||||
// we can now reconstruct the signed message and recover the peers
|
||||
// pubkey
|
||||
var signedMsg = xor(sessionToken, initNonce)
|
||||
var remoteRandomPubKeyS []byte
|
||||
if remoteRandomPubKeyS, err = secp256k1.RecoverPubkey(signedMsg, msg[:sigLen]); err != nil {
|
||||
return
|
||||
}
|
||||
// convert to ECDSA standard
|
||||
if remoteRandomPubKey, err = importPublicKey(remoteRandomPubKeyS); err != nil {
|
||||
return
|
||||
}
|
||||
|
||||
// now we find ourselves a long task too, fill it random
|
||||
var resp = make([]byte, authRespLen)
|
||||
// generate shaLen long nonce
|
||||
respNonce = resp[pubLen : pubLen+shaLen]
|
||||
if _, err = rand.Read(respNonce); err != nil {
|
||||
return
|
||||
}
|
||||
func decodeAuthMsg(prv *ecdsa.PrivateKey, token []byte, auth []byte) (*encHandshake, error) {
|
||||
var err error
|
||||
h := new(encHandshake)
|
||||
// generate random keypair for session
|
||||
if randomPrivKey, err = crypto.GenerateKey(); err != nil {
|
||||
return
|
||||
h.randomPrivKey, err = ecies.GenerateKey(rand.Reader, crypto.S256(), nil)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
// generate random nonce
|
||||
h.respNonce = make([]byte, shaLen)
|
||||
if _, err = rand.Read(h.respNonce); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
msg, err := crypto.Decrypt(prv, auth)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("could not decrypt auth message (%v)", err)
|
||||
}
|
||||
|
||||
// decode message parameters
|
||||
// signature || sha3(ecdhe-random-pubk) || pubk || nonce || token-flag
|
||||
h.initNonce = msg[authMsgLen-shaLen-1 : authMsgLen-1]
|
||||
copy(h.remoteID[:], msg[sigLen+shaLen:sigLen+shaLen+pubLen])
|
||||
rpub, err := h.remoteID.Pubkey()
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("bad remoteID: %#v", err)
|
||||
}
|
||||
h.remotePub = ecies.ImportECDSAPublic(rpub)
|
||||
|
||||
// recover remote random pubkey from signed message.
|
||||
if token == nil {
|
||||
// TODO: it is an error if the initiator has a token and we don't. check that.
|
||||
|
||||
// no session token means we need to generate shared secret.
|
||||
// ecies shared secret is used as initial session token for new peers.
|
||||
// generate shared key from prv and remote pubkey.
|
||||
if token, err = h.ecdhShared(prv); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
}
|
||||
signedMsg := xor(token, h.initNonce)
|
||||
remoteRandomPub, err := secp256k1.RecoverPubkey(signedMsg, msg[:sigLen])
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
h.remoteRandomPub, _ = importPublicKey(remoteRandomPub)
|
||||
return h, nil
|
||||
}
|
||||
|
||||
// authResp generates the encrypted authentication response message.
|
||||
func (h *encHandshake) authResp(prv *ecdsa.PrivateKey, token []byte) ([]byte, error) {
|
||||
// responder auth message
|
||||
// E(remote-pubk, ecdhe-random-pubk || nonce || 0x0)
|
||||
var randomPubKeyS []byte
|
||||
if randomPubKeyS, err = exportPublicKey(&randomPrivKey.PublicKey); err != nil {
|
||||
return
|
||||
resp := make([]byte, authRespLen)
|
||||
n := copy(resp, exportPubkey(&h.randomPrivKey.PublicKey))
|
||||
n += copy(resp[n:], h.respNonce)
|
||||
if token == nil {
|
||||
resp[n] = 0
|
||||
} else {
|
||||
resp[n] = 1
|
||||
}
|
||||
copy(resp[:pubLen], randomPubKeyS)
|
||||
// nonce is already in the slice
|
||||
resp[authRespLen-1] = tokenFlag
|
||||
|
||||
// encrypt using remote-pubk
|
||||
// auth = eciesEncrypt(remote-pubk, msg)
|
||||
// why not encrypt with ecdhe-random-remote
|
||||
if authResp, err = crypto.Encrypt(remotePubKey, resp); err != nil {
|
||||
return
|
||||
}
|
||||
return
|
||||
return ecies.Encrypt(rand.Reader, h.remotePub, resp, nil, nil)
|
||||
}
|
||||
|
||||
// importPublicKey unmarshals 512 bit public keys.
|
||||
func importPublicKey(pubKey []byte) (pubKeyEC *ecdsa.PublicKey, err error) {
|
||||
func importPublicKey(pubKey []byte) (*ecies.PublicKey, error) {
|
||||
var pubKey65 []byte
|
||||
switch len(pubKey) {
|
||||
case 64:
|
||||
@ -414,14 +378,15 @@ func importPublicKey(pubKey []byte) (pubKeyEC *ecdsa.PublicKey, err error) {
|
||||
default:
|
||||
return nil, fmt.Errorf("invalid public key length %v (expect 64/65)", len(pubKey))
|
||||
}
|
||||
return crypto.ToECDSAPub(pubKey65), nil
|
||||
// TODO: fewer pointless conversions
|
||||
return ecies.ImportECDSAPublic(crypto.ToECDSAPub(pubKey65)), nil
|
||||
}
|
||||
|
||||
func exportPublicKey(pubKeyEC *ecdsa.PublicKey) (pubKey []byte, err error) {
|
||||
if pubKeyEC == nil {
|
||||
return nil, fmt.Errorf("no ECDSA public key given")
|
||||
func exportPubkey(pub *ecies.PublicKey) []byte {
|
||||
if pub == nil {
|
||||
panic("nil pubkey")
|
||||
}
|
||||
return crypto.FromECDSAPub(pubKeyEC)[1:], nil
|
||||
return elliptic.Marshal(pub.Curve, pub.X, pub.Y)[1:]
|
||||
}
|
||||
|
||||
func xor(one, other []byte) (xor []byte) {
|
||||
|
||||
@ -2,51 +2,18 @@ package p2p
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"crypto/rand"
|
||||
"fmt"
|
||||
"net"
|
||||
"reflect"
|
||||
"testing"
|
||||
"time"
|
||||
|
||||
"github.com/ethereum/go-ethereum/crypto"
|
||||
"github.com/ethereum/go-ethereum/crypto/ecies"
|
||||
"github.com/ethereum/go-ethereum/p2p/discover"
|
||||
)
|
||||
|
||||
func TestPublicKeyEncoding(t *testing.T) {
|
||||
prv0, _ := crypto.GenerateKey() // = ecdsa.GenerateKey(crypto.S256(), rand.Reader)
|
||||
pub0 := &prv0.PublicKey
|
||||
pub0s := crypto.FromECDSAPub(pub0)
|
||||
pub1, err := importPublicKey(pub0s)
|
||||
if err != nil {
|
||||
t.Errorf("%v", err)
|
||||
}
|
||||
eciesPub1 := ecies.ImportECDSAPublic(pub1)
|
||||
if eciesPub1 == nil {
|
||||
t.Errorf("invalid ecdsa public key")
|
||||
}
|
||||
pub1s, err := exportPublicKey(pub1)
|
||||
if err != nil {
|
||||
t.Errorf("%v", err)
|
||||
}
|
||||
if len(pub1s) != 64 {
|
||||
t.Errorf("wrong length expect 64, got", len(pub1s))
|
||||
}
|
||||
pub2, err := importPublicKey(pub1s)
|
||||
if err != nil {
|
||||
t.Errorf("%v", err)
|
||||
}
|
||||
pub2s, err := exportPublicKey(pub2)
|
||||
if err != nil {
|
||||
t.Errorf("%v", err)
|
||||
}
|
||||
if !bytes.Equal(pub1s, pub2s) {
|
||||
t.Errorf("exports dont match")
|
||||
}
|
||||
pub2sEC := crypto.FromECDSAPub(pub2)
|
||||
if !bytes.Equal(pub0s, pub2sEC) {
|
||||
t.Errorf("exports dont match")
|
||||
}
|
||||
}
|
||||
|
||||
func TestSharedSecret(t *testing.T) {
|
||||
prv0, _ := crypto.GenerateKey() // = ecdsa.GenerateKey(crypto.S256(), rand.Reader)
|
||||
pub0 := &prv0.PublicKey
|
||||
@ -68,46 +35,84 @@ func TestSharedSecret(t *testing.T) {
|
||||
}
|
||||
|
||||
func TestEncHandshake(t *testing.T) {
|
||||
defer testlog(t).detach()
|
||||
for i := 0; i < 20; i++ {
|
||||
start := time.Now()
|
||||
if err := testEncHandshake(nil); err != nil {
|
||||
t.Fatalf("i=%d %v", i, err)
|
||||
}
|
||||
t.Logf("(without token) %d %v\n", i+1, time.Since(start))
|
||||
}
|
||||
|
||||
prv0, _ := crypto.GenerateKey()
|
||||
prv1, _ := crypto.GenerateKey()
|
||||
rw0, rw1 := net.Pipe()
|
||||
secrets := make(chan secrets)
|
||||
for i := 0; i < 20; i++ {
|
||||
tok := make([]byte, shaLen)
|
||||
rand.Reader.Read(tok)
|
||||
start := time.Now()
|
||||
if err := testEncHandshake(tok); err != nil {
|
||||
t.Fatalf("i=%d %v", i, err)
|
||||
}
|
||||
t.Logf("(with token) %d %v\n", i+1, time.Since(start))
|
||||
}
|
||||
}
|
||||
|
||||
func testEncHandshake(token []byte) error {
|
||||
type result struct {
|
||||
side string
|
||||
s secrets
|
||||
err error
|
||||
}
|
||||
var (
|
||||
prv0, _ = crypto.GenerateKey()
|
||||
prv1, _ = crypto.GenerateKey()
|
||||
rw0, rw1 = net.Pipe()
|
||||
output = make(chan result)
|
||||
)
|
||||
|
||||
go func() {
|
||||
pub1s, _ := exportPublicKey(&prv1.PublicKey)
|
||||
s, err := outboundEncHandshake(rw0, prv0, pub1s, nil)
|
||||
if err != nil {
|
||||
t.Errorf("outbound side error: %v", err)
|
||||
r := result{side: "initiator"}
|
||||
defer func() { output <- r }()
|
||||
|
||||
pub1s := discover.PubkeyID(&prv1.PublicKey)
|
||||
r.s, r.err = initiatorEncHandshake(rw0, prv0, pub1s, token)
|
||||
if r.err != nil {
|
||||
return
|
||||
}
|
||||
id1 := discover.PubkeyID(&prv1.PublicKey)
|
||||
if s.RemoteID != id1 {
|
||||
t.Errorf("outbound side remote ID mismatch")
|
||||
if r.s.RemoteID != id1 {
|
||||
r.err = fmt.Errorf("remote ID mismatch: got %v, want: %v", r.s.RemoteID, id1)
|
||||
}
|
||||
secrets <- s
|
||||
}()
|
||||
go func() {
|
||||
s, err := inboundEncHandshake(rw1, prv1, nil)
|
||||
if err != nil {
|
||||
t.Errorf("inbound side error: %v", err)
|
||||
r := result{side: "receiver"}
|
||||
defer func() { output <- r }()
|
||||
|
||||
r.s, r.err = receiverEncHandshake(rw1, prv1, token)
|
||||
if r.err != nil {
|
||||
return
|
||||
}
|
||||
id0 := discover.PubkeyID(&prv0.PublicKey)
|
||||
if s.RemoteID != id0 {
|
||||
t.Errorf("inbound side remote ID mismatch")
|
||||
if r.s.RemoteID != id0 {
|
||||
r.err = fmt.Errorf("remote ID mismatch: got %v, want: %v", r.s.RemoteID, id0)
|
||||
}
|
||||
secrets <- s
|
||||
}()
|
||||
|
||||
// get computed secrets from both sides
|
||||
t1, t2 := <-secrets, <-secrets
|
||||
// don't compare remote node IDs
|
||||
t1.RemoteID, t2.RemoteID = discover.NodeID{}, discover.NodeID{}
|
||||
// flip MACs on one of them so they compare equal
|
||||
t1.EgressMAC, t1.IngressMAC = t1.IngressMAC, t1.EgressMAC
|
||||
if !reflect.DeepEqual(t1, t2) {
|
||||
t.Errorf("secrets mismatch:\n t1: %#v\n t2: %#v", t1, t2)
|
||||
// wait for results from both sides
|
||||
r1, r2 := <-output, <-output
|
||||
|
||||
if r1.err != nil {
|
||||
return fmt.Errorf("%s side error: %v", r1.side, r1.err)
|
||||
}
|
||||
if r2.err != nil {
|
||||
return fmt.Errorf("%s side error: %v", r2.side, r2.err)
|
||||
}
|
||||
|
||||
// don't compare remote node IDs
|
||||
r1.s.RemoteID, r2.s.RemoteID = discover.NodeID{}, discover.NodeID{}
|
||||
// flip MACs on one of them so they compare equal
|
||||
r1.s.EgressMAC, r1.s.IngressMAC = r1.s.IngressMAC, r1.s.EgressMAC
|
||||
if !reflect.DeepEqual(r1.s, r2.s) {
|
||||
return fmt.Errorf("secrets mismatch:\n t1: %#v\n t2: %#v", r1.s, r2.s)
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
func TestSetupConn(t *testing.T) {
|
||||
|
||||
Loading…
Reference in New Issue
Block a user