bug(26.10): `chisel cut` failing for 26.10

[lczyk]

chisel cut against ubuntu 26.10 fails for every package on every arch with:

$ chisel cut --root rootfs --release ubunutu-26.10 --ignore=unstable libc6_libs
2026/07/06 22:08:18 Consulting release repository...
2026/07/06 22:08:19 Fetching current ubuntu-26.10 release...
2026/07/06 22:08:19 Processing ubuntu-26.10 release...
2026/07/06 22:08:29 Warning: This release is in the "unstable" maintenance status. See https://documentation.ubuntu.com/chisel/en/latest/reference/chisel-releases/chisel.yaml/#maintenance to be safe
2026/07/06 22:08:29 Selecting slices...
2026/07/06 22:08:29 Fetching ubuntu 26.10 stonking suite details...
2026/07/06 22:08:29 Release date: Mon, 06 Jul 2026 19:14:03 UTC
error: main/binary-arm64/Packages is missing from stonking main component digests

chisel only reads sha256 from InRelease. Stonking archives have only sha256 (at least so far).

$ curl -sSL http://ports.ubuntu.com/ubuntu-ports/dists/stonking/InRelease | grep -E '^(MD5Sum|SHA1|SHA256|SHA512):'
SHA512:

$ curl -sSL http://archive.ubuntu.com/ubuntu/dists/resolute/InRelease | grep -E '^(MD5Sum|SHA1|SHA256|SHA512):'
MD5Sum:
SHA1:
SHA256:

fix proposal

use strongest present acceptable checksum

[utkarsh2102]

Hi,

Stonking archives have only sha256 (at least so far).

FWIW, this is by design. Launchpad enabled a new publisher configuration for stonking which reduced the list of published hashes in the archive index files to sha512 (dropping md5sum, sha1 and sha256).

[lczyk]

alas, this should remain open in spite of #306 merging. there is a followup bug we have not foreseen and therefore a case we clearly need more test coverage here for:

manifest generation still hardcodes the per-package sha256, so on a sha512-only archive chisel cut dies if one of the cut slices is base-files_chisel (aka the only slice which generates the manifest).

e.g. https://github.com/canonical/chisel-releases/actions/runs/33528767060/job/99926248711 which prints:

2026/09/01 15:58:38 Extracting files from package "ncurses-base"...
2026/09/01 15:58:38 Extracting files from package "ncurses-bin"...
2026/09/01 15:58:38 Generating manifest at /var/lib/chisel/manifest.wall...
error: internal error: invalid manifest: package "base-files" missing sha256
Failed to cut slices. See above for details.

( works for other 26.04 jobs since they don't cut the manifest. spread tests always do )

[lczyk]

note that we include the manifest in all rocks, which means that we either block on this, or ship 26.10 rocks w/out the manifests until this is fixed. fyi @canonical/rocks

[cjdcordeiro]

note that we include the manifest in all rocks, which means that we either block on this, or ship 26.10 rocks w/out the manifests until this is fixed. fyi @canonical/rocks

let's not ship any rocks without the manifest. I see the PR is already up let's see if it's a quick merge 🤞

[lczyk]

let's not ship any rocks without the manifest.

agreed

let's see if it's a quick merge 🤞

'🤞' indeed, but i think we'll need a decision on how to proceed with #322 (review) first (see the comment re complications tehre)