fix packet encoding/decoding which seems to break after 2 billions packets sent #1743
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frochet
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use of stable ceil apply cargo fmt
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vanc
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Apr 25, 2024
quiche/src/packet.rs
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| // computes ceil of num_unacked.log2() | ||
| let min_bits = u64::BITS - num_unacked.leading_zeros(); | ||
| // get the num len in bytes | ||
| Ok((min_bits as f32 / 8.).ceil() as usize) |
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Ok((num_bits + 7) / 8 as usize) should be faster.
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Looks right! Good catch. The Result is not useful anymore either, and I removed it.
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Hello,
Long story short, I've been using the encoding/decoding logic of packet number for another purpose than encoding pn, and observed that it would start decoding incorrect values when reaching 2^31.
I dived into RFC9000, on the Appendix for the algorithmic details of encoding/decoding, and observed that the encoding algorithm in quiche does not match the encoding algorithm suggested by the RFC. I suppose there is a reason for this, but it eludes me.
So, this pull request does an implementation close to what is suggested (hopefully more efficient), and fixes my problem, and the bug with packet numbers too. I've also added test cases for packet encoding/decoding using example values from the RFC.
This passes all unit tests, and a simple integration test in which I downloaded a 5 GiB file through the H3 module using quiche-[client/server]. However, I am unsure about: