fix: strip headers listed in Connection header per RFC 7230 Section 6.1#450
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fix: strip headers listed in Connection header per RFC 7230 Section 6.1#450
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Per RFC 7230 Section 6.1, a proxy MUST parse the Connection header and remove any headers listed within it before forwarding the request. Previously, only the Connection header itself was stripped but headers named inside it (e.g., Connection: X-Custom-Header) were forwarded. This change: - Adds getConnectionHeaders() to parse Connection header values - Updates stripHttp1ConnectionHeaders() to also strip listed headers - Updates handleHttp1Req() and handleUndici() to strip listed headers - Adds tests for the new behavior Fixes #449
mcollina
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Eomm,
climba03003,
ilteoood and
jsumners
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climba03003
jsumners
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Jan 27, 2026
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No blockers, only suggestions.
climba03003
approved these changes
Jan 28, 2026
Address review comments: - Remove redundant !connectionHeader check since typeof covers it - Flip condition order to check comma first (more common case)
jsumners
approved these changes
Jan 31, 2026
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Summary
Per RFC 7230 Section 6.1, a proxy MUST parse the Connection header and remove any headers listed within it before forwarding the request.
Previously, only the Connection header itself was stripped but headers named inside it (e.g.,
Connection: X-Custom-Header) were forwarded to upstream.Changes
getConnectionHeaders()to parse Connection header valuesstripHttp1ConnectionHeaders()to also strip listed headershandleHttp1Req()andhandleUndici()to strip listed headersExample
Request from client:
Before: Only
Connectionwas stripped;X-Custom-Headerwas forwarded to upstream.After: Both
ConnectionandX-Custom-Headerare stripped before forwarding.Test plan
Fixes #449