Module rfc4475 

The RFC 4475 SIP torture-test corpus.

RFC 4475 collects messages designed to break naive parsers: legal ones that look illegal, illegal ones that look legal, and a long tail of whitespace, escaping and scalar-range edge cases. It is the standard correctness bar for a SIP implementation, so sipx runs it continuously rather than at the end.

The messages are recovered from the bit-exact archive in that RFC’s Appendix A by scripts/import-rfc4475-corpus.sh, not retyped: several cases hinge on octets that do not survive transcription (escaped NULs, UTF-8 display names, trailing whitespace). Run the script with --check to verify the committed corpus still matches the RFC.

What the classification is for

The RFC groups its messages by the layer that should object to them, and that grouping is the useful part. A negative Content-Length is a framing failure — the byte stream cannot be cut into messages at all. An overlarge CSeq is nothing of the sort: the message frames and forwards perfectly well, and the fault appears only when something reads CSeq. An implementation that conflates the two either drops messages it could have forwarded, or accepts messages it cannot frame.

So each case carries an Expect naming which layer must object, and the parser tests assert against that rather than against a bare pass/fail.

Structs

Case

One message from the corpus.

Enums

Expect

Which layer must object to a message, and how.

Fault

The structural fault a Expect::ParseErr case must produce.

Statics

CASES

Every message in the corpus, in RFC section order.

Functions

case

Look up a case by its RFC name.

classified

Every case the parser tests assert on.

expecting

Cases matching a given expectation.