SysAdmin
d354040bd6
Run #4278 with iter30's chroot scrub still produced different ISOs. The diagnostic was clean and pointed at a tight set of remaining divergences: * Inside the squashfs, three files differed: /var/cache/apt/pkgcache.bin /var/cache/apt/srcpkgcache.bin /var/cache/ldconfig/aux-cache — all post-install binary caches with internal pointers/timestamps that vary across runs. Standard reproducible-Debian practice is to drop them; `apt` regenerates pkgcache on first `apt-get update` (and implicitly when anything else needs it), and ldconfig regenerates aux-cache on its next run. * In the outer ISO TOC: /boot.catalog mtime May 7 21:27 vs May 7 21:44 /live/filesystem.squashfs May 7 21:27 vs May 7 21:44 — xorriso's `-update` and the boot-catalog rewrite were stamping files with wall-clock time, not SOURCE_DATE_EPOCH. Two additions to post_process_for_reproducibility: 1. Three more entries in the chroot rm list (apt's two pkgcaches and ldconfig aux-cache). 2. xorriso post-update fixups: -alter_date_r m "=${SOURCE_DATE_EPOCH}" / -volume_date c "=${SOURCE_DATE_EPOCH}" -volume_date m "=${SOURCE_DATE_EPOCH}" set every file's mtime in the ISO and both volume-descriptor dates to the pinned epoch. (`=N` is xorriso's syntax for a literal decimal epoch.) If diffoscope flagged everything in run #4278 honestly (its full output was 3 file diffs in the squashfs + the squashfs metadata size delta, then nothing — TOC was reduced to just the two mtime lines), this should clear M1.1. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
SilverMetal OS — Linux
Status: Phase 1 (planning) → moving to milestone 1.1 (reproducible Kicksecure fork build)
🔒 SilverMetal OS product line — we ship the operating system.
The reference SilverMetal flavour. Tier A — full kernel-level hardening, verified boot we control, Debian/Kicksecure-based.
Scope (v1)
See ../docs/roadmap.md Phase 1.
Hardening must-haves
- Kicksecure base (Debian-derived, hardened upstream)
- linux-hardened kernel + KSPP sysctl/build flags
- Secure Boot with our shim/MOK
- TPM2 PCR-bound LUKS2 unlock (Argon2id), full-disk encryption mandatory
- AppArmor strict profiles for browsers, mail, viewers, networked daemons
- GrapheneOS hardened_malloc as system allocator
- bubblewrap + Flatpak primary; firejail for legacy
.deb - nftables default-deny inbound, encrypted DNS, SilverVPN always-on default
- Zero upstream telemetry — verified by integration test
- SilverBrowser default (ungoogled-chromium-rebranded v1)
- SilverVPN integrated from existing
SilverLABS/SilverVPN(Linux client + tunnel service) - SilverSync v1 (Nextcloud-backed, client-side encryption)
- A/B updates with rollback, signed by our keys
- Optional amnesic session mode
Out of scope (v1)
- Atomic / immutable root (v1.1 —
ostreeexperiment) - dm-verity on
/(v1.1) - ARM64 / Apple Silicon (v2)
- Tor-by-default variant (sibling product later)
Directory layout
linux/
├── build/ # live-build pipeline, reproducible-build config
├── kernel/ # config fragments, linux-hardened pinning
├── overlay/ # /etc + /usr/share/silvermetal + skel hardening overlay
├── packages/
│ ├── include.list # what's installed
│ └── exclude.list # what's purged (snap, telemetry, etc.)
├── apparmor/ # custom strict profiles
├── nftables/ # default ruleset
├── installer/ # Calamares branding + hardened defaults
├── update-server/ # signing + repo hosting (infra-as-code)
└── tests/
├── lynis-baseline/
├── kspp-check/
└── telemetry-leak/
Verification gates (must pass before public alpha)
- Two clean builds from same commit → identical SHA256
kconfig-hardened-checkpasses- Lynis hardening score ≥ 90
- 30-min idle telemetry capture: zero packets to MS/Google/Apple/Mozilla/Canonical/Debian/analytics
- TPM tamper test: LUKS correctly falls back to passphrase
- AppArmor: every networked binary confined or documented
- Independent privacy-engineering review
Upstream we depend on
- Kicksecure — fork base
- linux-hardened — kernel patchset
- GrapheneOS hardened_malloc — allocator
- KSPP — kernel config authority
- secureblue — reference for v1.1 immutable design
SilverLABS/SilverVPN— VPN client + tunnel service (existing, integrated)