Fix malformed key generation message

Make nullTerminated argument explicit, easier to debug.

Fixes #67

CHANGELOG.md

@@ -15,6 +15,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Make `hostname` optional and pick `resolvedAddresses` if nil.
 
+### Fixed
+
+- Negotiation times out with SoftEther. [#67](https://github.com/keeshux/tunnelkit/issues/67)
+
 ## 1.6.1 (2019-04-07)
 
 ### Fixed

TunnelKit/Sources/Core/SessionProxy+Authenticator.swift

@@ -94,7 +94,7 @@ extension SessionProxy {
             raw.append(random1)
             raw.append(random2)
             
-            // opts
+            // opts (empty string)
             raw.appendSized(Z(UInt8(0)))
             
             // credentials
@@ -107,7 +107,7 @@ extension SessionProxy {
             }
 
             // peer info
-            raw.appendSized(Z(CoreConfiguration.peerInfo))
+            raw.appendSized(Z(CoreConfiguration.peerInfo, nullTerminated: true))
 
             if CoreConfiguration.logsSensitiveData {
                 log.debug("TLS.auth: Put plaintext (\(raw.count) bytes): \(raw.toHex())")

TunnelKit/Sources/Core/SessionProxy+EncryptionBridge.swift

@@ -71,7 +71,7 @@ extension SessionProxy {
             _ serverSessionId: Data?,
             _ size: Int) throws -> ZeroingData {
             
-            let seed = Z(label)
+            let seed = Z(label, nullTerminated: false)
             seed.append(clientSeed)
             seed.append(serverSeed)
             if let csi = clientSessionId {

TunnelKit/Sources/Core/ZeroingData.swift

@@ -66,6 +66,6 @@ func Z(_ data: Data) -> ZeroingData {
 //    return ZeroingData(data: data, offset: offset, count: count)
 //}
 
-func Z(_ string: String, nullTerminated: Bool = false) -> ZeroingData {
+func Z(_ string: String, nullTerminated: Bool) -> ZeroingData {
     return ZeroingData(string: string, nullTerminated: nullTerminated)
 }