Guard the Espressif echoserver forward cleanup

[ejohnstown]

WOLFSSH_FWD_LOCAL_CLEANUP now reaches applications, so the Espressif echoserver's handler for it runs where it used to be dead code. It was the only copy in the tree left unguarded.

• gate the handler on the channel id the library passes in the port parameter, so a late cleanup cannot close the next forward's socket
• guard the close against an open that failed after the setup, with nothing connected and the descriptor still -1

[wolfSSL-Fenrir-bot]

Fenrir Automated Review — PR #1255

No scan targets match the changed files in this PR. Review skipped.

[Copilot]

🔵 Needs a closer look

The cleanup path can leave the worker's forwarding descriptor open.

Pull request overview

Guards Espressif echoserver forwarding cleanup against stale channels and invalid descriptors.

Changes:

• Validates the channel ID before cleanup.
• Guards socket closing and resets forwarding state.

File summaries

File	Review
ide/Espressif/ESP-IDF/examples/wolfssh_echoserver/main/echoserver.c	Moderate issue (1 vote): appFd is not synchronized with the worker's fwdFd, so successful direct connections may remain open during cleanup.

Review details

Suppressed comments (1)

ide/Espressif/ESP-IDF/examples/wolfssh_echoserver/main/echoserver.c:519

• appFd is never populated by this Espressif file's direct-connect path (that path stores the successful socket only in the worker-local fwdFd), so this condition is false for every successful direct-tcpip connection. Once this cleanup callback is live, fwdFd is left open; please make the direct path and all close paths keep appFd in sync, or have cleanup close the worker's descriptor as well.

            if (ctx->appFd != (WS_SOCKET_T)-1) {
                WCLOSESOCKET(ctx->appFd);
                ctx->appFd = -1;
            }

• Files reviewed: 1/1 changed files
• Comments generated: 0
• Review effort level: Lite

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[wolfSSL-Fenrir-bot]

Fenrir Automated Review — PR #1255

No scan targets match the changed files in this PR. Review skipped.

[Copilot]

🔵 Needs a closer look

Reset fwdBufferIdx on teardown and other forward-close paths to prevent stale buffered data reuse.

Review details

Suppressed comments (1)

ide/Espressif/ESP-IDF/examples/wolfssh_echoserver/main/echoserver.c:1169

• fwdBufferIdx is not cleared when this cleanup path invalidates the descriptor. If target data was read but still pending in fwdBuffer (for example while the channel was not yet confirmed), a later forward reuses those bytes and sends them on the new channel. Reset fwdBufferIdx on this teardown and the other forward-close paths below.

                                fwdFd = -1;

• Files reviewed: 3/3 changed files
• Comments generated: 0 new
• Review effort level: Lite