Strip reverse proxy headers in SigV4 processor to fix SignatureDoesNo…#42
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Strip reverse proxy headers in SigV4 processor to fix SignatureDoesNo…#42
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…tMatch When tokenizer runs behind a reverse proxy (e.g., fly-proxy), standard proxy headers like X-Forwarded-For, Via, etc. get injected into requests. These headers were being signed by the SigV4 processor, but could then be modified by outbound proxies, causing AWS signature verification to fail. Also adds a FIXME noting that region/service parsing from the credential scope appears to be swapped (left unchanged to avoid breaking existing clients).
timflyio
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Mar 4, 2026
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timflyio
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wish we could just tell v4 signer api to ignore some headers.. other than that itch, lgtm.
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When tokenizer runs behind a reverse proxy (e.g., fly-proxy), standard proxy headers like X-Forwarded-For, Via, etc. get injected into requests. These headers were being signed by the SigV4 processor, but could then be modified by outbound proxies, causing AWS signature verification to fail.
Also adds a FIXME noting that region/service parsing from the credential scope appears to be swapped (left unchanged to avoid breaking existing clients).