fix: only allow minimally encoded CID tag#55
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Integers should always be minimally encoded, so should be the header of a tag.
rvagg
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May 15, 2026
| name: "CBOR tag", | ||
| found: tag as u8, | ||
| }), | ||
| found: tag, |
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this is not helpful now when head != 0xd8 and you've pulled an extra byte when you didn't need to
maybe just have two if blocks here, pull head check & error, pull tag check and error
rvagg
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May 15, 2026
| DecodeError::Mismatch { | ||
| name: "CBOR tag", | ||
| found: 0xf7 | ||
| found: 0xd9 |
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this passes whether we report head or the byte after it, since both are 0xd9. Some better inputs that distinguish:
- over-wide encoding of tag 42, assertion should be
found: 0xd9(the head):0xd9, 0x00, 0x2a, 0x66, 0x66, 0x6f, 0x6f, 0x62, 0x61, 0x72 - minimally-encoded header but wrong tag number, assertion should be
found: 0x29:0xd8, 0x29
The first exercises the head-width check; the second exercises the tag-value check.
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Integers should always be minimally encoded, so should be the header of a tag.