- From: RFC Errata System <rfc-editor@rfc-editor.org>
- Date: Sat, 25 Apr 2026 14:33:58 -0700 (PDT)
- To: robipolli@gmail.com, lucas@lucaspardue.com, httpbis-ads@ietf.org, mnot@mnot.net, tpauly@apple.com
- Cc: ietf@mariuskleidl.net, ietf-http-wg@w3.org, rfc-editor@rfc-editor.org
The following errata report has been submitted for RFC9530,
"Digest Fields".
--------------------------------------
You may review the report below and at:
https://www.rfc-editor.org/errata/eid8890
--------------------------------------
Type: Technical
Reported by: Marius Kleidl <ietf@mariuskleidl.net>
Section: B.4.
Original Text
-------------
8B 08 80 7B 22 68 65 6C 6C 6F
22 3A 20 22 77 6F 72 6C 64 22
7D 0A 03
Corrected Text
--------------
0B 09 80 7B 22 68 65 6C 6C 6F
22 3A 20 22 77 6F 72 6C 64 22
7D 0A 03
Notes
-----
The Brotli representation provided in the examples in B.4 (Figure 18) and B.6 (Figure 21) aren't valid. Trying to decompress them via Node.js' zlib package and the brotli CLI fails:
```
$ node -e "require('zlib').brotliDecompressSync(Buffer.from('8b08807b2268656c6c6f223a2022776f726c64227d0a03','hex'))"
node:zlib:432
throw self[kError];
^
Error: unexpected end of file
[...]
code: 'Z_BUF_ERROR'
}
```
```
$ echo 8b08807b2268656c6c6f223a2022776f726c64227d0a03 | xxd -r -p | brotli -d -c
corrupt input [con]
```
In addition, the SHA-256 over the bytes in the original text is MklYnI/SsUF/5X7enJ2TU+DFjodRObdKLFaPPLe/Kcw=, not d435Qo+nKZ+gLcUHn7GQtQ72hiBVAgqoLsZnZPiTGPk= as used by the RFC in the Repr-Digest header field. The SHA-512 digest in Figure 21 is similarly incorrect.
The correct text only differs in the first two bytes. With this change, the response content is a valid Brotli compression of `{"hello": "world"}\n`. The SHA-256 and SHA-512 digests in the Repr-Digest header fields then also match the representation's digests.
Instructions:
-------------
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--------------------------------------
RFC9530 (draft-ietf-httpbis-digest-headers-13)
--------------------------------------
Title : Digest Fields
Publication Date : February 2024
Author(s) : R. Polli, L. Pardue
Category : PROPOSED STANDARD
Source : HTTP
Stream : IETF
Verifying Party : IESG
Received on Saturday, 25 April 2026 21:34:05 UTC