Decode chunked request bodies; reject invalid framing per RFC 9112#210
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swhitty merged 2 commits intoApr 26, 2026
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HTTPDecoder.readBody now honors Transfer-Encoding: chunked (RFC 9112 §7.1) by routing the body through a new HTTPChunkedTransferDecoder, the read-side mirror of HTTPChunkedTransferEncoder. Trailer fields are consumed and discarded. readBody also throws HTTPDecoder.Error on framing violations: - both Content-Length and Transfer-Encoding present (§6.1) - non-numeric or negative Content-Length (§6.3 swhitty#5) - Transfer-Encoding whose final coding is not `chunked` (§6.1) Throwing surfaces as a connection-close (RFC-permitted for unrecoverable framing errors); HTTPServer.handleConnection has a TODO to upgrade this to an explicit 400 Bad Request response in a future change. readBody's signature changes from (from:length:) to (from:contentLength:transferEncoding:). Both decodeRequest and decodeResponse pass headers[.contentLength] and headers[.transferEncoding]. Closes TVT-287 Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Codecov Report❌ Patch coverage is
Additional details and impacted files@@ Coverage Diff @@
## main #210 +/- ##
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+ Coverage 92.67% 92.74% +0.06%
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Files 69 70 +1
Lines 3551 3638 +87
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+ Hits 3291 3374 +83
- Misses 260 264 +4 ☔ View full report in Codecov by Sentry. |
Six additional HTTPDecoderTests targeting the uncovered branches in HTTPChunkedTransferDecoder and HTTPDecoder.readBody: - chunkExt_IsIgnored (RFC 9112 §7.1: chunk-ext after `;` is parsed but ignored) - invalidChunkSize_ThrowsError (non-hex chunk-size) - missingCRLFAfterChunkData_ThrowsError (chunk-data not followed by CRLF) - truncatedChunkSize_ThrowsError / truncatedChunkData_ThrowsError (stream ends mid-line / mid-chunk -> SocketError.disconnected) - unsupportedTransferEncoding_ThrowsError (e.g. `gzip`) Lifts HTTPChunkedDecodedSequence.swift to 86.79%/88.73% region/line coverage and HTTPDecoder.swift's TVT-287 additions to 100%. Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
swhitty
approved these changes
Apr 26, 2026
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Summary
HTTPDecoder.readBodynow honorsTransfer-Encoding: chunked(RFC 9112 §7.1) by routing the body through a newHTTPChunkedTransferDecoder— the read-side mirror of the existingHTTPChunkedTransferEncoder. Trailer fields (RFC 9112 §7.1.2) are consumed and discarded.readBodyalso throwsHTTPDecoder.Erroron framing violations:Content-LengthandTransfer-Encodingpresent (§6.1, smuggling prevention)Content-Length(§6.3 Added most of the HTTP status codes and phrases #5, "unrecoverable error")Transfer-Encodingwhose final coding is notchunked(§6.1)HTTPServer.handleConnectionhas a// TODOto upgrade this to an explicit400 Bad Requestresponse in a future change.readBody's signature changes from(from:length:)to(from:contentLength:transferEncoding:). BothdecodeRequestanddecodeResponsenow pass the relevant headers.Closes TVT-287.
Test plan
HTTPDecoderTestscases covering chunked multi-chunk decode, terminator-only, trailer ignore, conflicting CL+TE, non-numeric CL, negative CL.readBody/test-helper call sites updated to the new signature.