Verify connect negotiation reply at the call site

mullvad · Nov 2, 2023 · e689f81 · e689f81
1 parent c371e9d
commit e689f81
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Showing 2 changed files with 10 additions and 10 deletions.
diff --git a/ios/MullvadTransport/Socks5/Socks5ConnectNegotiation.swift b/ios/MullvadTransport/Socks5/Socks5ConnectNegotiation.swift
@@ -56,21 +56,15 @@ struct Socks5ConnectNegotiation {
     }
 
     /**
-     Parse the bytes that comprise the preamble of a connect reply and evaluate the status code. Upon success read the endpoint data to produce the complete
-     reply and finish negotiation.
+     Parse the bytes that comprise the preamble of a connect reply. Upon success read the endpoint data to produce the complete reply and finish negotiation.
 
      The following fields are contained within the first 4 bytes: socks version, status code, reserved field, address type.
      */
     private func handlePartialReply(data: Data) throws {
-        // Parse partial reply that contains the status code.
+        // Parse partial reply that contains the status code and address type.
         let (statusCode, addressType) = try parsePartialReply(data: data)
 
-        // Verify the status code.
-        guard case .succeeded = statusCode else {
-            throw Socks5Error.connectionRejected(statusCode)
-        }
-
-        // Parse server bound endpoint when partial reply indicates success.
+        // Parse server bound endpoint to produce the complete reply.
         let endpointReader = Socks5EndpointReader(
             connection: connection,
             addressType: addressType,

diff --git a/ios/MullvadTransport/Socks5/Socks5Connection.swift b/ios/MullvadTransport/Socks5/Socks5Connection.swift
@@ -202,7 +202,13 @@ final class Socks5Connection {
         let negotiation = Socks5ConnectNegotiation(
             connection: remoteConnection,
             endpoint: remoteServerEndpoint,
-            onComplete: { [self] _ in stream() },
+            onComplete: { [self] reply in
+                if case .succeeded = reply.status {
+                    stream()
+                } else {
+                    handleError(Socks5Error.connectionRejected(reply.status))
+                }
+            },
             onFailure: handleError
         )
         negotiation.perform()