fix: register channel before completing forwardLocal future to avoid dropping early CHANNEL_DATA#141
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vicajilau merged 1 commit intoTerminalStudio:masterfrom Mar 19, 2026
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Just a gentle ping on this PR — I really need this fix urgently, would appreciate a quick review when you get a chance. Thanks! @xtyxtyx @vicajilau |
vicajilau
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Mar 19, 2026
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Bug: When using forwardLocal() (direct-tcpip), if the remote server sends data (e.g. its SSH version string) immediately after the TCP connection is established, that data arrives as SSH_MSG_CHANNEL_DATA in the same TCP segment as SSH_MSG_CHANNEL_OPEN_CONFIRMATION. _handleChannelConfirmation completes the future via Completer.complete(), which schedules the async continuation as a microtask. Before that microtask runs, _handleChannelData processes the CHANNEL_DATA — but _channels[id] is still null at this point, so the data is silently dropped by ?.handleMessage().
Fix: Call _acceptChannel() synchronously inside _handleChannelConfirmation before completing the future, so the channel is registered in _channels immediately. _waitChannelOpen then simply returns the already-registered controller.
Impact: Fixes SSH connections through bastion hosts where the target server sends its version string immediately upon connection (which is standard behavior per RFC 4253).